Search results for: peptide inhibitor
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 572

Search results for: peptide inhibitor

212 Shielding Engineered Islets with Mesenchymal Stem Cells Enhance Survival under Hypoxia by Inhibiting p38 MAPK

Authors: Bhawna Chandravanshi, Ramesh Bhonde

Abstract:

In the present study, we focused on the improvisation of islet survival in hypoxia. The Islet-like cell aggregates (ICAs) derived from Wharton's jelly mesenchymal stem cells (WJ-MSC) were cultured with and without WJ-MSC for 48h in hypoxia and normoxia and tested for their direct trophic effect on β cell survival. The WJ MSCs themselves secreted insulin upon glucose challenge and expressed the pancreatic markers at both transcription and translational level (C-peptide, Insulin, Glucagon and Glut 2). Direct contact of MSCs with ICAs facilitate the highest viability under hypoxia as evidenced by fluorescein diacetate/propidium iodide and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cytokine analysis of the co-cultured ICAs revealed amplification of anti-inflammatory cytokine-like TGFβ and TNFα accompanied by depletion of pro-inflammatory cytokines. The increment in VEGF and PDGFa was also seen showing their ability to vascularize upon transplantation. This was further accompanied by reduction in total reactive oxygen species, nitric oxide, and super oxide ions and down-regulation of Caspase3, Caspase8, p53 and up regulation of Bcl2 confirming prevention of apoptosis in ICAs. There was a significant reduction in the expression of p38 protein in the presence of MSCs making the ICAs responsive to glucose. Taken together our data demonstrate for the first time that the WJ-MSC expressed pancreatic markers and their supplementation protected engineered islets against hypoxia, oxidative stress, and inflammatory cytokines by inhibiting p38 MAPK protein.

Keywords: hypoxia, islet-like cell aggregates, inflammatory cytokines, oxidative stress

Procedia PDF Downloads 237
211 Formulation and Evaluation of Lisinopril Microspheres for Nasal Delivery

Authors: S. S. Patil, R. M. Mhetre, S. V. Patil

Abstract:

Lisinopril is an angiotensin converting enzyme inhibitor used in the treatment of hypertension and heart failure in prophylactic treatment after myocardial infarction and in diabetic nephropathy. However, it is very poorly absorbed from gastro-intestinal tract. Intranasal administration is an ideal alternative to the parenteral route for systemic drug delivery. Formulating multiparticulate system with mucoadhesive polymers provide a significant increase in the nasal residence time. The aim of the present approach was to overcome the drawbacks of the conventional dosage forms of lisinopril by formulating intranasal microspheres with Carbopol 974P NF and HPMC K4 M along with film forming polymer ethyl cellulose.The microspheres were prepared by emulsion solvent evaporation method. The prepared microspheres were characterized for encapsulation efficiency, drug loading, particle size, and surface morphology, degree of swelling, ex vivo mucoadhesion, drug release, ex vivo diffusion studies. All formulations has shown entrapment efficiency between 80 to more than 95%, mucoadhesion was more than 80 % and drug release up to 90 %. Ex vivo studies revealed tht the improved bioavailability of drug compared to oral drug administration. Both in vitro and in vivo studies conclude that combination of Carbopol and HPMC based microspheres shown better results than single carbopol based microspheres for the delivery of lisinopril.

Keywords: microspheres, lisinopril, nasal delivery, solvent evaporation method

Procedia PDF Downloads 505
210 The Effects of Highly Active Antiretroviral Therapy (HAART) on the Expression of Muc1 and P65 in a Cervical Cancer Cell Line, HCS-2

Authors: K. R. Thabethe, G. A. Adefolaju, M. J. Hosie

Abstract:

Cervical cancer is the third most commonly diagnosed cancer globally and it is one of three AIDS defining malignancies. Highly active antiretroviral therapy (HAART) is a combination of three or more antiretroviral drugs and has been shown to play a significant role in reducing the incidence of some AIDS defining malignancies, although its effect on cervical cancer is still unclear. The aim of this study was to investigate the relationship between cervical cancer and HAART. This was achieved by studying the expression of two signalling molecules expressed in cervical cancer; MUC1 and P65. Following the 24 hour treatment of a cervical cancer cell line, HCS-2, with drugs which are commonly used as part of HAART at their clinical plasma concentrations, real-time qPCR and immunofluorescence were used in order to study gene and protein expression. A one way ANOVA followed by a Tukey Kramer Post Hoc test was conducted using JMP 11 software on both sets of data. The drug classified as a protease inhibitor (PI) (i.e. LPV/r) reduced MUC1 and P65 gene and protein expression more than the other drug tested. PIs are known to play a significant role in cell death, therefore the cells were thought to be more susceptible to cell death following treatment with PIs. In conclusion, the drugs used, especially the PI showed some anticancer effects by facilitating cell death through decreased gene and protein expression of MUC1 and P65 and present promising agents for cancer treatment.

Keywords: cervical cancer, haart, MUC1, P65

Procedia PDF Downloads 311
209 Clustering of Natural and Nature Derived Compounds for Cardiovascular Disease: Pharmacophore Modeling

Authors: S. Roy, R. Rekha, K. Sriram, G. Subhadra, R. Johana

Abstract:

Cardiovascular disease remains a leading cause of death in most industrialized countries. Many chemical drugs are available in the market which targets different receptor proteins related to cardiovascular diseases. Of late the traditional herbal drugs are safer when compared to chemical drugs because of its side effects. However, many herbal remedies used in treating cardiovascular diseases have not undergone scientific assessment to prove its pharmacological activities. There are many natural compounds, nature derived and Natural product mimic compounds are available which are in the market as approved drug. In the most of the cases drug activity at the molecular level are not known. Here we have categorized those compounds with our experimental compounds in different classes based on the structural similarity and physicochemical properties, using a tool, Chemmine and has attempted to understand the mechanism of the action of a experimental compound, which are clustered with Simvastatin, Lovastatin, Mevastatin and Pravastatin. Target protein molecule for Simvastatin, Lovastatin, Mevastatin and Pravastatin is HMG-CoA reductase, so we concluded that the experimental compound may be able to bind to the same target. Molecular docking and atomic interaction studies with simvastatin and our experimental compound were compared. A pharmacophore modeling was done based on the experimental compound and HMG-CoA reductase inhibitor.

Keywords: molecular docking, physicochemical properties, pharmacophore modeling structural similarity, pravastatin

Procedia PDF Downloads 298
208 Muscle Relaxant Dantrolene Repurposed to Treat Alzheimer's Disease

Authors: Huafeng Wei

Abstract:

Failures of developing new drugs primarily based on the amyloid pathology hypothesis after decades of efforts internationally lead to changes of focus targeting alternative pathways of pathology in Alzheimer’s disease (AD). Disruption of intracellular Ca2+ homeostasis, especially the pathological and excessive Ca2+ release from the endoplasmic reticulum (ER) via ryanodine receptor (RyRs) Ca2+ channels, has been considered an upstream pathology resulting in major AD pathologies, such as amyloid and Tau pathology, mitochondria damage and inflammation, etc. Therefore, dantrolene, an inhibitor of RyRs that reduces the pathological Ca2+ release from ER and a clinically available drug for the treatment of malignant hyperthermia and muscle spasm, is expected to ameliorate AD multiple pathologies synapse and cognitive dysfunction. Our own studies indicated that dantrolene ameliorated impairment of neurogenesis and synaptogenesis in neurons developed from induced pluripotent stem cells (iPSCs) originated from skin fibroblasts of either familiar (FAD) or sporadic (SAD) AD by restoring intracellular Ca2+ homeostasis. Intranasal administration of dantrolene significantly increased its passage across the blood-brain barrier (BBB) and, therefore its brain concentrations and durations. This can render dantrolene a more effective therapeutic drug with fewer side effects for chronic AD treatment. This review summarizes the potential therapeutic and side effects of dantrolene and repurposes intranasal dantrolene as a disease-modifying drug for future AD treatment.

Keywords: Alzheimer's disease, calcium, drug development, dementia, neurodegeneration, neurogenesis

Procedia PDF Downloads 188
207 Differential Response of Cellular Antioxidants and Proteome Expression to Salt, Cadmium and Their Combination in Spinach (Spinacia oleracea)

Authors: Rita Bagheri, Javed Ahmed, Humayra Bashir, M. Irfan Qureshi

Abstract:

Agriculture lands suffer from a combination of stresses such as salinity and metal contamination including cadmium at the same time. Under such condition of multiple stresses, plant may exhibit unique responses different from the stress occurring individually. Thus, it would be interesting to investigate that how plant respond to combined stress at level of antioxidants and proteome expression, and identifying the proteins which are involved in imparting stress tolerance. With an approach of comparative proteomics and antioxidant analysis, present study investigates the response of Spinacia oleracea to salt (NaCl), cadmium (Cd), and their combination (NaCl+Cd) stress. Two-dimensional gel electrophoresis was used for resolving leaf proteome, and proteins of interest were identified using PDQuest software. A number of proteins expressed differentially, those indicated towards their roles in imparting stress tolerance, were digested by trypsin and analyzed on mass spectrometer for peptide mass fingerprinting (PMF). Data signals were then matched with protein databases using MASCOT. Results show that NaCl, Cd and both together (NaCl+Cd) induce oxidative stress which was highest in combined stress of Cd+NaCl. Correspondingly, the activities of enzymatic antioxidants viz., SOD, APX, GR and CAT, and non-enzymatic antioxidants had highest changes under combined stress compares to single stress over their respective controls. Among the identified proteins, several interesting proteins were identified that may be have role in Spinacia oleracia tolerance in individual and combinatorial stress of salt and cadmium. The functional classification of identified proteins indicates the importance and necessity of keeping higher ratio of defence and disease responsive proteins.

Keywords: Spinacia oleracea, Cd, salinity, proteomics, antioxidants, combinatorial stress

Procedia PDF Downloads 360
206 Antidiabetic and Admet Pharmacokinetic Properties of Grewia Lasiocarpa E. Mey. Ex Harv. Stem Bark Extracts: An in Vitro and in Silico Study

Authors: Akwu N. A., Naidoo Y., Salau V. F., Olofinsan K. A.

Abstract:

Grewia lasiocarpa E. Mey. ex Harv. (Malvaceae) is a Southern African medicinal plant indigenously used with other plants for birthing problems. The anti-diabetic properties of the hexane, chloroform, and methanol extracts of Grewia lasiocarpa stem bark were assessed using in vitro α-glucosidase enzyme inhibition assay. The predictive in silico drug-likeness and toxicity properties of the phytocompounds were conducted using the pKCSM, ADMElab, and SwissADME computer-aided online tools. The highest α-glucosidase percentage inhibition was observed in the hexane extract (86.76%, IC50= 0.24 mg/mL), followed by chloroform (63.08%, IC50= 4.87 mg/mL) and methanol (53.22%, IC50= 9.41 mg/mL); while acarbose, the standard anti-diabetic drug was (84.54%, IC50= 1.96 mg/mL). The α-glucosidase assay revealed that the hexane extract exhibited the strongest carbohydrate inhibiting capacity and is a better inhibitor than the standard reference drug-acarbose. The computational studies also affirm the results observed in the in vitroα-glucosidaseassay. Thus, the extracts of G. lasiocarpa may be considered a potential plant-sourced compound for treating type 2 diabetes mellitus. This is the first study on the anti-diabetic properties of Grewia lasiocarpa hexane, chloroform, and methanol extracts using in vitro and in silico models.

Keywords: grewia lasiocarpa, α-glucosidase inhibition, anti-diabetes, ADMET

Procedia PDF Downloads 80
205 Depressant Effects of 2-PMPA through Reduction of p-CREB (Ser133) and mGluR5 Level in Prefrontal Cortex of C57BL/6 Mice

Authors: Sang-Sun Yoon, Yea-Hyun Leem, Sangmee Ahn Jo

Abstract:

The N-acetylated-alpha-linked-acidic (NAAG) peptidase inhibitor 2-phosphonomethyl pentanedioic acid (2-PMPA) has demonstrated to be neuroprotective against glutamate-mediated neuron degeneration and neurological disorders such as ischemia. Several studies have demonstrated impaired psychiatric function by altered glutamate carboxypeptidase II expression, although 2-PMPA has not yet been studied. Thus, we investigated effect of 2-PMPA on depressive-like phenotype using C57BL/6 mice. Treatment of 2-PMPA (10 mg/kg for 6 days/daily, ip injection) on C57BL/6 naïve mice showed depressive-like symptoms such as decreased social preference, but did not affect the immobility measured by tail suspension test. Reduction of phosphorylated cAMP-responsive element binding (p-CREB) known as a representative marker of depressive-like behavior was observed in layer 1 and piriform cortex subregions of the prefrontal cortex of 2-PMPA-treated mice. The immunoreactivity of metabotropic glutamate receptors 5 (mGluR5) that mediate phosphorylation of CREB was also decreased in layer 1 and piriform cortex subregions of the prefrontal cortex of 2-PMPA injected mice. Thus, our results suggest that dysregulation of the GCPII or NAAG by 2-PMPA treatment is likely to be associated with pathogenesis of depression and further studies are needed to understand whether the reduced NAAG level or enhanced glutamate level in the brain is involved in this response.

Keywords: depression, GCPII, 2-PMPA, p-CREB, mGluR5

Procedia PDF Downloads 245
204 Effect of Far Infrared and Endothelial Cell Growth Supplement on Human Umbilical Vascular Endothelial Cells

Authors: Ming-Tzu Tsai, Jui-Ting Hsu, Chia-Chieh Lin, Feng-Tsai Chiang, Cheng-Chin Huang

Abstract:

Far infrared (FIR), an invisible and short electromagnetic waves ranges from 6-14 μm also defines as the “growth ray.” Although the mechanism of FIR is still unknown, most data have suggested that FIR could accelerate the skin microcirculation by elevating the blood flow and nitric-oxide (NO) synthesis. In this present work, the effect of FIR irradiation and endothelial cell growth supplement (ECGS) on human umbilical vascular endothelial cells (HUVECs) was evaluated. To understand whether the cell viability and NO production of HUVECs affected by NO, cells with/without ECGS were treated in the presence or absence of L-NAME, an eNOS inhibitor. For FIR exposure, FIR-emitted ceramic powders consisted of a variety of well-mixed metal oxides were developed. The results showed that L-NAME did had a strong effect on the inhibition of NO production, especially in the ECGS-treated group. However, the cell viability of each group was rarely affected in the presence of L-NAME. Cells with the incubation of ECGS showed much higher cell viability compared to the control. Moreover, NO production of HUVECs exposed to FIR irradiation was significantly inhibited in the presence of L-NAME. It suggested that NO could play a role modulating the downstream signals of HUVECs during FIR exposure.

Keywords: far-infrared irradiation (FIR), nitric oxide (NO), endothelial nitric oxide synthase (eNOS), endothelial cell growth supplement (ECGS)

Procedia PDF Downloads 404
203 Synthesis of a Library of Substituted Isoquinolines Based on a Triazolization Strategy, and Their Anti-HIV and C-X-C Chemokine Receptor Type 4 Antagonist Activity

Authors: Mastaneh Safarnejad Shad, Wim Dehaen, Steven De Jonghe

Abstract:

Since CXCR4 is the main coreceptor of HIV-1 and plays an important role in human immunodeficiency virus (HIV) entry, numerous efforts were directed towards the discovery of new classes of small molecules that act as CXCR4 antagonists. In addition, CXCR4 antagonists are potentially useful in the treatment of several other disorders, such as cancer cell metastasis, leukemia cell proliferation, rheumatoid arthritis, and pulmonary fibrosis. Since AMD3100 (plerixafor) is the only CXCR4 antagonist which obtained approval by the Food and Drug Administration (FDA), we were motivated to investigate a new category of molecules as CXCR4 antagonists. Most of the scaffolds which have been studied so far as CXCR4 antagonists are based on the tetrahydroquinoline (THQ) moiety in which AMD11070 (mavorixafor), GSK-812394, and TIQ15 displayed the most potent CXCR4 antagonism. Due to the high potency of these scaffolds, two different series of compounds were prepared in this work. In the first set, the THQ moiety is coupled to an amine chain and various isoquinoline derivatives (prepared by an in-house developed triazolization strategy), of which the upper part of molecules is identical to AMD11070 and TIQ15. In the second category of compounds, the THQ moiety was simplified by the synthesis of a substituted pyridine moiety. In order to investigate if CXCR4 antagonism requires the presence of an isoquinoline moiety, the corresponding pyridine analogues were also prepared. In both series of compounds, potent CXCR4 antagonism was noticed.

Keywords: CXCR4 coreceptor, CXCR4 antagonists, HIV inhibitor, tetrahydroquinoline

Procedia PDF Downloads 172
202 Assessing Digestive Enzymes Inhibitory Properties of Anthocyanins and Procyanidins from Apple, Red Grape, Cinnamon

Authors: Pinar Ercan, Sedef N. El

Abstract:

The goals of this study were to determine the total anthocyanin and procyanidin contents and their in vitro bioaccessibilities of apple, red grape and cinnamon by a static in vitro digestion method reported by the COST FA1005 Action INFOGEST, as well as in vitro inhibitory effects of these food samples on starch and lipid digestive enzymes. While the highest total anthocyanin content was found in red grape (164.76 ± 2.51 mg/100 g), the highest procyanidin content was found in cinnamon (6432.54±177.31 mg/100 g) among the selected food samples (p<0.05). The anthocyanin bioaccessibilities were found as 10.23±1 %, 8.23±0.64 %, and 8.73±0.70 % in apple, red grape, and cinnamon, respectively. The procyanidin bioaccessibilities of apple, red grape, and cinnamon were found as 17.57±0.71 %, 14.08±0.74 % and 18.75±1.49 %, respectively. The analyzed apple, red grape and cinnamon showed the inhibitory activity against α-glucosidase (IC50 544.27±21.94, 445.63±15.67, 1592±17.58 μg/mL, respectively), α-amylase (IC50 38.41±7.26, 56.12±3.60, 3.54±0.86 μg/mL, respectively), and lipase (IC50 52.65±2.05, 581.70±54.14, 49.63±2.72 μg/mL, respectively). Red grape sample showed the highest inhibitory activity against α-glucosidase, cinnamon showed the highest inhibitory activity against α-amylase and lipase according to IC50 (concentration of inhibitor required to produce a 50% inhibition of the initial rate of reaction) and Catechin equivalent inhibition capacity (CEIC50) values. This study reported that apple, grape and cinnamon samples can inhibit the activity of digestive enzymes in vitro. The consumption of these samples would be used in conjunction with a low-calorie diet for body weight management.

Keywords: anthocyanin, α-amylase, α-glucosidase, lipase, procyanidin

Procedia PDF Downloads 152
201 LGR5 and Downstream Intracellular Signaling Proteins Play Critical Roles in the Cell Proliferation of Neuroblastoma, Meningioma and Pituitary Adenoma

Authors: Jin Hwan Cheong, Mina Hwang, Myung Hoon Han, Je Il Ryu, Young ha Oh, Seong Ho Koh, Wu Duck Won, Byung Jin Ha

Abstract:

Leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) has been reported to play critical roles in the proliferation of various cancer cells. However, the roles of LGR5 in brain tumors and the specific intracellular signaling proteins directly associated with it remain unknown. Expression of LGR5 was first measured in normal brain tissue, meningioma, and pituitary adenoma of humans. To identify the downstream signaling pathways of LGR5, siRNA-mediated knockdown of LGR5 was performed in SH-SY5Y neuroblastoma cells followed by proteomics analysis with 2-dimensional polyacrylamide gel electrophoresis (2D-PAGE). In addition, the expression of LGR5-associated proteins was evaluated in LGR5-inꠓhibited neuroblastoma cells and in human normal brain, meningioma, and pituitary adenoma tissue. Proteomics analysis showed 12 protein spots were significantly different in expression level (more than two-fold change) and subsequently identified by peptide mass fingerprinting. A protein association network was constructed from the 12 identified proteins altered by LGR5 knockdown. Direct and indirect interactions were identified among the 12 proteins. HSP 90-beta was one of the proteins whose expression was altered by LGR5 knockdown. Likewise, we observed decreased expression of proteins in the hnRNP subfamily following LGR5 knockdown. In addition, we have for the first time identified significantly higher hnRNP family expression in meningioma and pituitary adenoma compared to normal brain tissue. Taken together, LGR5 and its downstream sigꠓnaling play critical roles in neuroblastoma and brain tumors such as meningioma and pituitary adenoma.

Keywords: LGR5, neuroblastoma, meningioma, pituitary adenoma, hnRNP

Procedia PDF Downloads 29
200 Effect of Oxytocin on Cytosolic Calcium Concentration of Alpha and Beta Cells in Pancreas

Authors: Rauza Sukma Rita, Katsuya Dezaki, Yuko Maejima, Toshihiko Yada

Abstract:

Oxytocin is a nine-amino acid peptide synthesized in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the hypothalamus. Oxytocin promotes contraction of the uterus during birth and milk ejection during breast feeding. Although oxytocin receptors are found predominantly in the breasts and uterus of females, many tissues and organs express oxytocin receptors, including the pituitary, heart, kidney, thymus, vascular endothelium, adipocytes, osteoblasts, adrenal gland, pancreatic islets, and many cell lines. On the other hand, in pancreatic islets, oxytocin receptors are expressed in both α-cells and β-cells with stronger expression in α- cells. However, to our knowledge there are no reports yet about the effect of oxytocin on cytosolic calcium reaction on α and β-cell. This study aims to investigate the effect of oxytocin on α-cells and β-cells and its oscillation pattern. Islet of Langerhans from wild type mice were isolated by collagenase digestion. Isolated and dissociated single cells either α-cells or β-cells on coverslips were mounted in an open chamber and superfused in HKRB. Cytosolic concentration ([Ca2+]i) in single cells were measured by fura-2 microfluorimetry. After measurement of [Ca2+]i, α-cells were identified by subsequent immunocytochemical staining using an anti-glucagon antiserum. In β-cells, the [Ca2+]i increase in response to oxytocin was observed only under 8.3 mM glucose condition, whereas in α-cells, [Ca2+]i an increase induced by oxytocin was observed in both 2.8 mM and 8.3 mM glucose. The oscillation incidence was induced more frequently in β-cells compared to α-cells. In conclusion, the present study demonstrated that oxytocin directly interacts with both α-cells and β-cells and induces increase of [Ca2+]i and its specific patterns.

Keywords: α-cells, β-cells, cytosolic calcium concentration, oscillation, oxytocin

Procedia PDF Downloads 166
199 Site-Specific Delivery of Hybrid Upconversion Nanoparticles for Photo-Activated Multimodal Therapies of Glioblastoma

Authors: Yuan-Chung Tsai, Masao Kamimura, Kohei Soga, Hsin-Cheng Chiu

Abstract:

In order to enhance the photodynamic/photothermal therapeutic efficacy on glioblastoma, the functionized upconversion nanoparticles with the capability of converting the deep tissue penetrating near-infrared light into visible wavelength for activating photochemical reaction were developed. The drug-loaded nanoparticles (NPs) were obtained from the self-assembly of oleic acid-coated upconversion nanoparticles along with maleimide-conjugated poly(ethylene glycol)-cholesterol (Mal-PEG-Chol), as the NP stabilizer, and hydrophobic photosensitizers, IR-780 (for photothermal therapy, PTT) and mTHPC (for photodynamic therapy, PDT), in aqueous phase. Both the IR-780 and mTHPC were loaded into the hydrophobic domains within NPs via hydrophobic association. The peptide targeting ligand, angiopep-2, was further conjugated with the maleimide groups at the end of PEG adducts on the NP surfaces, enabling the affinity coupling with the low-density lipoprotein receptor-related protein-1 of tumor endothelial cells and malignant astrocytes. The drug-loaded NPs with the size of ca 80 nm in diameter exhibit a good colloidal stability in physiological conditions. The in vitro data demonstrate the successful targeting delivery of drug-loaded NPs toward the ALTS1C1 cells (murine astrocytoma cells) and the pronounced cytotoxicity elicited by combinational effect of PDT and PTT. The in vivo results show the promising brain orthotopic tumor targeting of drug-loaded NPs and sound efficacy for brain tumor dual-modality treatment. This work shows great potential for improving photodynamic/photothermal therapeutic efficacy of brain cancer.

Keywords: drug delivery, orthotopic brain tumor, photodynamic/photothermal therapies, upconversion nanoparticles

Procedia PDF Downloads 169
198 Neuroprotective Effect of Crocus sativus against Cerebral Ischemia in Rats

Authors: Rehab F. Abdel-Rahman, Sally A. El Awdan, Rehab R. Hegazy, Dina F. Mansour, Hanan A. Ogaly, Marwan Abdelbaset

Abstract:

Disorders of the cerebral circulation are the leading cause of numerous neurological and psychiatric illnesses. The transient middle cerebral artery occlusion model (MCAO) is considered to be a reliable and reproducible rodent model of cerebral ischemia. The purpose of the current study was to examine the neuroprotective effects of Crocus sativus (saffron) in a rat model of left middle cerebral artery MCAO. Male Wistar rats were anesthetized and subjected to 1 h of MCAO followed by 48 h reperfusion or sham surgery. One group of the ischemia operated animals was kept as left brain ischemia/reperfusion (I/R). Another 2 operated groups received saffron extract (100 or 200 mg/kg, i.p) four times (60 min before the surgery, during the surgery, and on days 1 and 2 after the occlusion). During the experiment, behavioral tests were performed. After 72 h the animals were euthanized and their left brain hemispheres were used in the biochemical, histopathological, and immunohistochemical studies. Saffron administration revealed an improvement in I/R-induced alteration of locomotor balance and coordination ability of rats. Moreover, saffron decreased the brain content of malondialdehyde, nitric oxide, brain natriuretic peptide and vascular endothelial growth factor with significant increase of reduced glutathione. Immunohistochemical evaluation of caspase-3 and Bax protein expression revealed reduction in I/R-enhanced apoptosis in saffron treated rats. In conclusion, saffron treatment decreases ischemic brain injury in association with inhibition of apoptotic and oxidative cell death in a dose dependent manner.

Keywords: caspase-3, cerebral ischemia, Crocus sativus, rats, vascular endothelial growth factor

Procedia PDF Downloads 240
197 Binding Studies of Complexes of Anticancer Drugs with DNA and Enzymes Involved in DNA Replication Using Molecular Docking and Cell Culture Techniques

Authors: Fouzia Perveen, Rumana Qureshi

Abstract:

The presently studied twelve anticancer drugs are the cytotoxic agents which inhibit the replication of DNA and activity of enzymes involved in DNA replication namely topoisomerase-II, polymerase and helicase and have shown remarkable anticancer activity in clinical trials. In this study, we performed molecular docking studies of twelve antitumor drugs against DNA and DNA enzymes in the presence and absence of ascorbic acid (AA) and developed the quantitative structure-activity relationship (QSAR) model for anticancer activity screening. A number of electronic and steric descriptors were calculated using MOE software package. QSAR was established showing a correlation of binding strength with various physicochemical descriptors. Out of these twelve, eight cytotoxic drugs were tested on Non-Small Cell Lung Cancer cell lines (H-157 and H-1299) in the absence and presence of ascorbic acid and experimental IC50 values were calculated. From the docking studies, binding constants were calculated indicating the strength of drug-DNA and drug-enzyme complex formation and it was correlated to the IC50 values (both experimental and theoretical). These results can offer useful references for directing the molecular design of DNA enzyme inhibitor with improved anticancer activity.

Keywords: ascorbic acid, binding constant, cytotoxic agents, cell culture, DNA, DNA enzymes, molecular docking

Procedia PDF Downloads 403
196 Hybrid Sol-Gel Coatings for Corrosion Protection of AA6111-T4 Aluminium Alloy

Authors: Shadatul Hanom Rashid, Xiaorong Zhou

Abstract:

Hybrid sol-gel coatings are the blend of both advantages of inorganic and organic networks have been reported as environmentally friendly anti-corrosion surface pre-treatment for several metals, including aluminum alloys. In this current study, Si-Zr hybrid sol-gel coatings were synthesized from (3-glycidoxypropyl)trimethoxysilane (GPTMS), tetraethyl orthosilicate (TEOS) and zirconium(IV) propoxide (TPOZ) precursors and applied on AA6111 aluminum alloy by dip coating technique. The hybrid sol-gel coatings doped with different concentrations of cerium nitrate (Ce(NO3)3) as a corrosion inhibitor were also prepared and the effect of Ce(NO3)3 concentrations on the morphology and corrosion resistance of the coatings were examined. The surface chemistry and morphology of the hybrid sol-gel coatings were analyzed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The corrosion behavior of the coated aluminum alloy samples was evaluated by electrochemical impedance spectroscopy (EIS). Results revealed that good corrosion resistance of hybrid sol-gel coatings were prepared from hydrolysis and condensation reactions of GPTMS, TEOS and TPOZ precursors deposited on AA6111 aluminum alloy. When the coating doped with cerium nitrate, the properties were improved significantly. The hybrid sol-gel coatings containing lower concentration of cerium nitrate offer the best inhibition performance. A proper doping concentration of Ce(NO3)3 can effectively improve the corrosion resistance of the alloy, while an excessive concentration of Ce(NO3)3 would reduce the corrosion protection properties, which is associated with defective morphology and instability of the sol-gel coatings.

Keywords: AA6111, Ce(NO3)3, corrosion, hybrid sol-gel coatings

Procedia PDF Downloads 125
195 Supply Chain Technology Adoption in Textile and Apparel Industry

Authors: Zulkifli Mohamed Udin, Lee Khai-Loon, Mohamad Ghozali Hassan

Abstract:

In today’s dynamic business environment, the competition is no longer between firms, but between supply chains to gain competitive advantages. The global manufacturing sector, especially the textile and apparel industry are essentially known for its supply chain dependency. The delicate nature of its business leads to emphasis on the smooth movement of upstream and downstream supply chain. The nature of this industry, however, result in huge dynamic flow of physical, information, and financial. The dynamic management of these flows requires adoption of supply chain technologies. Even though technology is widely implemented and studied in many industries by researchers, adoption of supply chain technologies in Malaysian textile and apparel industry is limited. There is relatively a handful academic study conducted on recent developments in Malaysian textile and apparel industry and supply chain technology adoption indicate a major gap in supply chain performance studies. Considering the importance given to Third Industrial Master Plan by the government Malaysia, it is necessary to understand the power of supply chain technology adoptions. This study aims to investigate supply chain technology adoption by textile and apparel companies in Malaysia. The result highlighted the benefits perceived by textile and apparel companies from supply chain technologies. The indifference of small and medium enterprises to operation management acts as a major inhibitor to the adoption of supply chain technologies, since they have resource limitations. This study could be used as a precursor for further detailed studies on this issue.

Keywords: supply chain technology adoption, supply chain performance, textile, apparel industry

Procedia PDF Downloads 467
194 Structure-Based Virtual Screening and in Silico Toxicity Test of Compounds against Mycobacterium tuberculosis 7,8-Diaminopelargonic Acid Aminotransferase (MtbBioA)

Authors: Junie B. Billones, Maria Constancia O. Carrillo, Voltaire G. Organo, Stephani Joy Y. Macalino, Inno A. Emnacen, Jamie Bernadette A. Sy

Abstract:

One of the major interferences in the Philippines’ tuberculosis control program is the widespread prevalence of Mtb strains that are resistant to known drugs, such as the MDR-TB (Multi Drug Resistant Tuberculosis) and XDR-TB (Extensively Drug Resistant Tuberculosis). Therefore, there is a pressing need to search for novel Mtb drug targets in order to be able to combat these drug resistant strains. The enzyme 7,8-diaminopelargonic acid aminotransferase enzyme, or more commonly known as BioA, is one such ideal target, as it is known that humans do not possess this enzyme. BioA primarily plays a key role in Mtb’s lipid biosynthesis pathway; more specifically in the synthesis of the enzyme cofactor biotin. In this study, structure-based pharmacophore screening, docking, and ADMET evaluation of compounds obtained from the DrugBank chemical database were performed against the MtbBioA enzyme. Results of the screening, docking, ADMET, and TOPKAT calculations revealed that out of the 6,516 compounds in the library, only 7 compounds indicated more favorable binding energies as compared to the enzyme’s known inhibitor, amiclenomycin (ACM), as well as good solubility and toxicity properties. Moreover, out of these 7 compounds, Molecule 6 exhibited the best solubility and toxicity properties. In the future, these lead compounds may then be subjected to bioactivity assays in vitro or in vivo for further evaluation of its therapeutic efficacy.

Keywords: 7, 8-diaminopelargonic acid aminotransferase, BioA, pharmacophore, molecular docking, ADMET, TOPKAT

Procedia PDF Downloads 427
193 Antidepressant-Like Effects of EQC-34, a 5HT3 Receptor Antagonist in Neurobehavioral Mouse Model of Depression

Authors: D: Gupta, M. Radhakrishnan, Y. Kurhe, D. Thangaraj

Abstract:

Depression is among the leading causes of death worldwide. The current pharmacotherapy is associated with poor compliance, resistance and relapse, which necessitate the development of novel compounds with better efficacy. The present study designed and synthesized EQC-34 (N-cyclohexyl-3-ethoxyquinoxalin-2-carboxamide) as novel serotonin type-3 (5HT3) antagonist and evaluated its antidepressant-like effects using neurobehavioral mouse model. 5HT3 antagonism (as pA2 value) was determined on the longitudinal smooth muscle of guinea-pig ileum against 2-methyl-5HT (a 5HT3 agonist). The doses were calculated by dose response of basal locomotor activity. Consequently, effects of EQC-34 on neurobehavioral parameters were measured in forced swim (FST) and tail suspension test (TST). The possible mechanism was estimated by interaction study with fluoxetine (a selective serotonin reuptake inhibitor) and mCPBG (1-(m-chlorophenyl)-biguanide, a selective 5HT3 agonist), and confirmed by potentiation of head twitch response by 5hydroxy-L-tryptophan (5HTP). EQC-34 (1-4 mg/kg, i.p.) produced significant decreased behavioral despair effects in FST and TST. It potentiated fluoxetine response, while mCPBG reduced EQC-34 activity in FST. Further, EQC-34 potentiated 5HTP induced head twitch response. EQC-34 revealed potential antidepressant-like effects, which may involve 5HT3 receptor mediated facilitation of 5HT neurotransmission, thereby reversing the pathological deficiency of monoamines (5HT) observed in depression. Thus, it may be further investigated as promising agent to improve therapeutics of depression.

Keywords: depression, forced swim test, 5HT3 receptor antagonist, serotonin

Procedia PDF Downloads 411
192 Hydrofracturing for Low Temperature Waxy Reservoirs: Problems and Solutions

Authors: Megh Patel, Arjun Chauhan, Jay Thakkar

Abstract:

Hydrofracturing is the most prominent but at the same time expensive, highly skilled and time consuming well stimulation technique. Due to high cost and skilled labor involved, it is generally carried out as the consummate solution among other well stimulation techniques. Considering today’s global petroleum market, no gaffe or complications could be entertained during fracturing, as it would further hamper the current dwindling economy. The literature would be dealing with the challenges encountered during fracturing low temperature waxy reservoirs and the prominent solutions to overcome such teething troubles. During fracturing treatment for, shallow and high freezing point waxy oil reservoirs, the first line problems are to overcome uncompleted breakdown, uncompleted cleanup of fracturing fluids and cold damages to the formations by injecting cold fluid (fluid at ambient conditions). Injecting fracturing fluids at ambient conditions have the tendency to decrease the near wellbore reservoir temperature below the freezing point of oil reservoir and hence leading to wax deposition around the wellbore thereby hampering the fluid production as well as fracture propagation. To overcome such problems, solutions such as hot fracturing fluid injection, encapsulated heat generating hydraulic fracturing fluid system, and injection of wax inhibitor techniques would be discussed. The paper would also be throwing light on changes in rheological properties occurred during heating fracturing fluids and solutions to deal with it taking economic considerations into account.

Keywords: hydrofracturing, waxy reservoirs, low temperature, viscosity, crosslinkers

Procedia PDF Downloads 225
191 An Inverse Docking Approach for Identifying New Potential Anticancer Targets

Authors: Soujanya Pasumarthi

Abstract:

Inverse docking is a relatively new technique that has been used to identify potential receptor targets of small molecules. Our docking software package MDock is well suited for such an application as it is both computationally efficient, yet simultaneously shows adequate results in binding affinity predictions and enrichment tests. As a validation study, we present the first stage results of an inverse-docking study which seeks to identify potential direct targets of PRIMA-1. PRIMA-1 is well known for its ability to restore mutant p53's tumor suppressor function, leading to apoptosis in several types of cancer cells. For this reason, we believe that potential direct targets of PRIMA-1 identified in silico should be experimentally screened for their ability to inhibitcancer cell growth. The highest-ranked human protein of our PRIMA-1 docking results is oxidosqualene cyclase (OSC), which is part of the cholesterol synthetic pathway. The results of two followup experiments which treat OSC as a possible anti-cancer target are promising. We show that both PRIMA-1 and Ro 48-8071, a known potent OSC inhibitor, significantly reduce theviability of BT-474 breast cancer cells relative to normal mammary cells. In addition, like PRIMA-1, we find that Ro 48-8071 results in increased binding of mutant p53 to DNA in BT- 474cells (which highly express p53). For the first time, Ro 48-8071 is shown as a potent agent in killing human breast cancer cells. The potential of OSC as a new target for developing anticancer therapies is worth further investigation.

Keywords: inverse docking, in silico screening, protein-ligand interactions, molecular docking

Procedia PDF Downloads 415
190 Profile of Cross-Reactivity Allergens Highlighted by Multiplex Technology “Alex Microchip Technique” in the Diagnosis of Type I Hypersensitivity

Authors: Gadiri Sabiha

Abstract:

Introduction: Current allergy diagnostic tools using Multiplex technology have made it possible to increase the efficiency of the search for specific IgE. This opportunity is provided by the newly developed “Alex Biochip”, consisting of a panel of 282 allergens in native and molecular form, a CCD inhibitor, and the potential for detecting cross-reactive allergens. We evaluated the performance of this technology in detecting cross-reactivity in previously explored patients. Material/Method: The sera of 39 patients presenting sensitization and polysensitization profiles were explored. The search for specific IgE is carried out by the Alex ® IgE Biochip, and the results are analyzed by nature and by molecular family of allergens using specific software. Results/Discussion: The analysis gave a particular profile of cross-reactivity allergens: 33% for the Ole e1 family, 31% for NPC2, 26% for storage proteins, 20% for Tropomyosin, 10% for LTPs, 10% for Arginine Kinase and 10% for Uteroglobin CCDs were absent in all patients. The “Ole e1” allergen is responsible for a pollen-pollen cross allergy. The storage proteins found and LTP are not species-specific, causing cross-pollen-food allergy. The nDer p2 of the NPC2 family is responsible for cross-reactivity between mite species. Conclusion: The cross-reactivities responsible for mixed syndromes at diagnosis in our patients were dominated by pollen-pollen and pollen-food syndromes. They allow the identification of severity factors linked to the prognosis and the best-adapted immunotherapy.

Keywords: specific IgE, allergy, cross reactivity, molecular allergens

Procedia PDF Downloads 43
189 Regulating Nanocarrier and Mononuclear Phagocyte System Interactions through Esomeprazole-Based Preconditioning Strategy

Authors: Zakia Belhadj, Bing He, Hua Zhang, Xueqing Wang, Wenbing Dai, Qiang Zhang

Abstract:

Mononuclear phagocyte system (MPS) forms an abominable obstacle hampering the tumor delivery efficiency of nanoparticles. Passively targeted nanocarriers have received clinical approval over the past 20 years. However, none of the actively targeted nanocarriers have entered clinical trials. Thus it is important to endue effective targeting ability to actively targeted approaches by overcoming biological barriers to nanoparticle drug delivery. Here, it presents that an Esomeprazole-based preconditioning strategy for regulating nanocarrier-MPS interaction to substantially prolong circulation time and enhance tumor targeting of nanoparticles. In vitro, the clinically approved proton pump inhibitor Esomeprazole “ESO” was demonstrated to reduce interactions between macrophages and subsequently injected targeted vesicles by interfering with their lysosomal trafficking. Of note, in vivo studies demonstrated that ESO pretreatment greatly decreased the liver and spleen uptake of c(RGDm7)-modified vesicles, highly enhanced their tumor accumulation, thereby provided superior therapeutic efficacy of c(RGDm7)-modified vesicles co-loaded with Doxorubicin (DOX) and Gefitinib (GE). This MPS-preconditioning strategy using ESO provides deeper insights into regulating nanoparticles interaction with the phagocytic system and enhancing their cancer cells' accessibility for anticancer therapy.

Keywords: esomeprazole (ESO), mononuclear phagocyte system (MPS), preconditioning strategy, targeted lipid vesicles

Procedia PDF Downloads 151
188 A Cros Sectional Observational Study of Prescription Pattern of Gastro-Protective Drugs with Non-Steroidal Anti-Inflammatory Drugs in Nilgiris, India

Authors: B.S. Roopa

Abstract:

Objectives: To investigate the prevalence of concomitant use of GPDs in patients treated with NSAIDs and GPDs in recommended dose and frequency as prophylaxis. And also to know the association between risk factors and prescription of GPDs in patients treated with NSAIDs. Methods: Study was a prospective, observational, cross-sectional survey. Data from patients with prescription of NSAIDs at the out-patient departments of secondary care Hospital, Nilgiris, India were collected in a specially designed proforma for a period of 45 days. Analysis using χ2 tests for discrete variables. Factors that might be associated with prescription of GPD with NSIADs were assessed in multiple logistic regression models. Results: Three hundred and three patients were included in this study, and the rate of GPD prescription was 89.1%. Most of the patients received H2-receptor antagonist, and, to a lesser degree, antacid and proton pump inhibitor. Patients with history of GI ulcer/bleeding were much more likely to be co-prescribed GPD than those who had no history of GI disorders .Compared with patients who were managed in general outpatient clinic, those managed in Secondary care hospital in Nilgrisis, India were more likely to receive GPD. Conclusions: The prescription rate of GPD with NSAIDs is high. Patients were prescribed with H2RA with dose of 150mg twice daily, which are not effective in reducing the risk of NSAIDs induced gastric ulcer. Only the frequency of NSAIDs prescription was considered significant determinant for the co-prescription with GPAs in patients who are < 65 years and ≥ 65 years old.

Keywords: gastro protective agents, non steridol anti inlfammatory agents

Procedia PDF Downloads 273
187 Anti-diabetic Potential of Olive (Olea Europaea) Leaves Extract: In Vitro and in Vivo Evaluation

Authors: Sobhy El-Sohaimy, Abduvali Toshev, Hanem Mansour

Abstract:

(1) Objective: The main objective of the current study was to evaluate in an In Vitro and In Vivo, the potential activity of olive leaves extract (OLE) in the treatment and/or preventing the diabetes mellitus type II and related implications; (2) Methodology: Five groups of male rats were used in the current study: group (1)- negative control (normal); group (2)- positive control, streptozotocin (STZ) induced rats; group (3)-diabetic rats treated with metformin (200 mg/kg) plus OLE (200 mg/kg); group 4- diabetic rats treated with metformin (200 mg/kg); group 5- diabetic rats treated with OLE (200 mg/kg). A four-week regime of oral treatment was administered once daily; (3) Results: Diabetic rats treated with metformin + OLE clearly showed normal blood glucose level (121.67 ± 5.49 mg/dl), and glycated hemoglobin (HbA1c) (3.70 ± 0.10%). The combination of metformin + OLE obviously showed a superior improvement in the lipid profile (TG, TC, HDL and LDL) compared to both metformin and OLE individually. The histological examination revealed that the combination of metformin + Olive leaves extract successfully repaired of the liver, kidneys, and pancreatic tissues in diabetic rats to be near to the normal status; (4) Conclusion: Finally, it can be concluded that, the combination of metformin and OLE exhibited a superior improvement than metformin and OLE individually which emphasized the promising adjuvant role of the OLE in the treatment protocol of diabetes mellitus type II.

Keywords: olive (olea europaea) leaves extracts, hypoglycemic agents, cytotoxicity, nitic oxide scavenging activity, α-glucose oxidase inhibitor

Procedia PDF Downloads 51
186 Targeting NLRP3 Inflammasome Activation: A New Mechanism Underlying the Protective Effects of Nafamostat Against Acute Pancreatitis

Authors: Jiandong Ren, Lijun Zhao, Peng Chen

Abstract:

Nafamostat (NA), a synthetic broad-spectrum serine protease inhibitor, has been routinely employed for the treatment of acute pancreatitis (AP) and other inflammatory-associated diseases in some East Asia countries. Although the potent inhibitory activity against inflammation-related proteases such as thrombin, trypsin, kallikrein, plasmin, coagulation factors and complement factors is generally considered to be responsible for the anti-inflammatory effects of NA, precise target and molecular mechanism underlying the anti-inflammatory activity in the treatment of AP remain largely unknown yet. As an intracellular inflammatory signaling platform, the NOD-like receptor protein 3 (NLRP3) inflammasome is recently identified to be involved in the development of AP. In present study, we have revealed that NA alleviated pancreatic injury in a caerulein-induced AP model by inhibiting the NLRP3 inflammasome activation in pancreas. Mechanistically, NA interacted with HDAC6, a cytoplasmic deacetylase implicated in the NLRP3 inflammasome pathway, and efficiently abrogated the function of HDAC6. This property enabled NA to influence HDAC6 dependent NF-κB transcriptional activity and thus block NF-κB-driven transcriptional priming of NLRP3 inflammasome. Moreover, NA exerted the potential to interfere HDAC6-mediated intracellular transport of NLRP3, thereby leading to the failure of NLRP3 inflammasome activation. Our current work has provided valuable insight into the molecular mechanism underlying the immunomodulatory effect of NA in treatment of AP, highlighting its promising application in prevention of NLRP3 inflammasome-associated inflammatory pathological damage.

Keywords: acute pancreatitis, HDAC6, nafamostat, NLRP3 inflammasome

Procedia PDF Downloads 32
185 Serum Interlukin-8 and Immunomodulation in Beta Thalassemia Patients

Authors: Shahira El Shafie, Hanaa Eldash, Engy Ghabbour, Mohamed Eid

Abstract:

Several immunologic defects can be found in patients with beta-thalassemia, among which the impairment of neutrophil phagocytic function is of utmost importance. Attention has been directed to the role of proinflammatory cytokines in neutrophil chemotaxis and phagocytosis. Interleukin-8 (IL-8) is an important chemotactic and activation peptide for neutrophils; changes in IL-8 level and potential correlation with neutrophil function can be relevant to immunomodulation pathophysiology in beta-thalassemia patients. This case-control study aimed to evaluate IL-8 level and to assess granulocyte recruitment, as markers of immunomodulation, in poly-transfused thalassemia patients attending Fayoum University Hospitals. The study was conducted on 50 patients with ß thalassemia and 32 age-matched controls. 21/50 patients were transfused more than ten times, and 29/50 were transfused in a lower frequency. Patients and controls were subjected to thorough history taking and clinical examination, measurement of IL-8 level using human IL-8 ELISA kit, and Rebuck skin window technique (RSWT) to assess granulocyte recruitment. Our data showed statistically significant higher levels of IL-8 in ß thalassemia patients compared to control with a much higher difference in patients transfused more than ten times. Neutrophil recruitment was significantly lower in ß thalassemia patients compared to control at 4 hours and 24 hours test time. Although IL-8, the main chemotactic pro-inflammatory cytokine showed a higher level in thalassemia patients, neutrophils recruitment was significantly lower, especially in those receiving more than ten transfusion times. Our findings suggest a possible role of other neutrophil chemotactic factors, defective neutrophil response, or increased IL-8 as compensation of abnormal function. We recommend the use of IL-8 and Rebuck skin window technique as useful markers of immunomodulation in thalassemia and further study for these biomarkers to assess their clinical implications and impact on the management of thalassemia patients.

Keywords: beta-thalassemia, Interleukin-8, Rebuck skin window technique, immunomodulation

Procedia PDF Downloads 169
184 Comparing Double-Stranded RNA Uptake Mechanisms in Dipteran and Lepidopteran Cell Lines

Authors: Nazanin Amanat, Alison Tayler, Steve Whyard

Abstract:

While chemical insecticides effectively control many insect pests, they also harm many non-target species. Double-stranded RNA (dsRNA) pesticides, in contrast, can be designed to target unique gene sequences and thus act in a species-specific manner. DsRNA insecticides do not, however, work equally well for all insects, and for some species that are considered refractory to dsRNA, a primary factor affecting efficacy is the relative ease by which dsRNA can enter a target cell’s cytoplasm. In this study, we are examining how different structured dsRNAs (linear, hairpin, and paperclip) can enter mosquito and lepidopteran cells, as they represent dsRNA-sensitive and refractory species, respectively. To determine how the dsRNAs enter the cells, we are using chemical inhibitors and RNA interference (RNAi)-mediated knockdown of key proteins associated with different endocytosis processes. Understanding how different dsRNAs enter cells will ultimately help in the design of molecules that overcome refractoriness to RNAi or develop resistance to dsRNA-based insecticides. To date, we have conducted chemical inhibitor experiments on both cell lines and have evidence that linear dsRNAs enter the cells using clathrin-mediated endocytosis, while the paperclip dsRNAs (pcRNAs) can enter both species’ cells in a clathrin-independent manner to induce RNAi. An alternative uptake mechanism for the pcRNAs has been tentatively identified, and the outcomes of our RNAi-mediated knockdown experiments, which should provide corroborative evidence of our initial findings, will be discussed.

Keywords: dsRNA, RNAi, uptake, insecticides, dipteran, lepidopteran

Procedia PDF Downloads 43
183 Development and Validation of High-Performance Liquid Chromatography Method for the Determination and Pharmacokinetic Study of Linagliptin in Rat Plasma

Authors: Hoda Mahgoub, Abeer Hanafy

Abstract:

Linagliptin (LNG) belongs to dipeptidyl-peptidase-4 (DPP-4) inhibitor class. DPP-4 inhibitors represent a new therapeutic approach for the treatment of type 2 diabetes in adults. The aim of this work was to develop and validate an accurate and reproducible HPLC method for the determination of LNG with high sensitivity in rat plasma. The method involved separation of both LNG and pindolol (internal standard) at ambient temperature on a Zorbax Eclipse XDB C18 column and a mobile phase composed of 75% methanol: 25% formic acid 0.1% pH 4.1 at a flow rate of 1.0 mL.min-1. UV detection was performed at 254nm. The method was validated in compliance with ICH guidelines and found to be linear in the range of 5–1000ng.mL-1. The limit of quantification (LOQ) was found to be 5ng.mL-1 based on 100µL of plasma. The variations for intra- and inter-assay precision were less than 10%, and the accuracy values were ranged between 93.3% and 102.5%. The extraction recovery (R%) was more than 83%. The method involved a single extraction step of a very small plasma volume (100µL). The assay was successfully applied to an in-vivo pharmacokinetic study of LNG in rats that were administered a single oral dose of 10mg.kg-1 LNG. The maximum concentration (Cmax) was found to be 927.5 ± 23.9ng.mL-1. The area under the plasma concentration-time curve (AUC0-72) was 18285.02 ± 605.76h.ng.mL-1. In conclusion, the good accuracy and low LOQ of the bioanalytical HPLC method were suitable for monitoring the full pharmacokinetic profile of LNG in rats. The main advantages of the method were the sensitivity, small sample volume, single-step extraction procedure and the short time of analysis.

Keywords: HPLC, linagliptin, pharmacokinetic study, rat plasma

Procedia PDF Downloads 223