Muzaffar Iqbal

Diosmin downregulates the expression of T cell receptors, pro-inflammatory cytokines and NF-κB activation against LPS-induced acute lung injury in mice.

Diosmin, a natural flavonoid glycoside present abundantly in the pericarp of various citrus fruits. Because of its anti-inflammatory and antioxidant properties, it can be used in many diseases. In this study, we investigated the possible protective mechanisms of the diosmin on LPS-induced lung injury through inhibition of T cell receptors, pro-inflammatory cytokines and NF-κB activation. Animals were pretreated with diosmin (50 and 100mg/kg, p.o.) for seven days prior to lipopolysaccharides (LPS) treatment. LPS administration increased neutrophils, monocytes, lymphocytes, total leukocyte count (TLC) and platelets which were decreased by diosmin. We observed that mice exposed to LPS showed increased malondialdehyde level and MPO activity whereas marked decrease in glutathione content. These changes were significantly reversed by treatment with diosmin in a dose dependent manner. Diosmin treatment showed a substantial reduction in T cell (CD4(+) and CD8(+)) receptors and pro-inflammatory (IL-2(+) and IL-17(+)) cytokines in whole blood. In addition, RT-PCR analysis revealed increased mRNA expression of IL-6, IL-17, TNF-α, and NF-κB in the LPS group, while reduced by treatment with diosmin. Western blot analysis confirmed the increased protein expression of IL-1β, TNF-α and NF-κB p65 in the LPS group and treatment of animals with diosmin reversed these effects. The levels of cytoplasmic p-IκB-α and p-NF-κB p65 expression also were mitigated by diosmin. The histological examinations revealed protective effect of diosmin while LPS group aggravated lung injury. These results support the potential for diosmin to be investigated as a potential agent for the treatment of lung injury and inflammatory diseases.

Carbon tetrachloride-induced hepatotoxicity in rat is reversed by treatment with riboflavin

Liver is a vital organ for the detoxification of toxic substances present in the body and hepatic injury is associated with excessive exposure to toxicants. The present study was designed to evaluate the possible hepatoprotective effects of riboflavin against carbon tetrachloride (CCl4) induced hepatic injury in rats. Rats were divided into six groups. Hepatotoxicity was induced by the administration of a single intraperitoneal dose of CCl4 in experimental rats. Riboflavin was administered at 30 and 100mg/kg by oral gavage to test its protective effect on hepatic injury biochemically and histopathologically in the blood/liver and liver respectively. The administration of CCl4 resulted in marked alteration in serum hepatic enzymes (like AST, ALT and ALP), oxidant parameters (like GSH and MDA) and pro-inflammatory cytokine TNF-α release from blood leukocytes indicative of hepatic injury. Changes in serum hepatic enzymes, oxidant parameters and TNF-α production induced by CCl4 were reversed by riboflavin treatment in a dose dependent manner. Treatment with standard drug, silymarin also reversed CCl4 induced changes in biomarkers of liver function, oxidant parameters and inflammation. The biochemical observations were paralleled by histopathological findings in rat liver both in the case of CCl4 and treatment groups. In conclusion, riboflavin produced a protective effect against CCl4-induced liver damage. Our study suggests that riboflavin may be used as a hepato-protective agent against toxic effects caused by CCl4 and other chemical agents in the liver.

Rapid determination of canagliflozin in rat plasma by UHPLC-MS/MS using negative ionization mode to avoid adduct-ions formation.

Canagliflozin is the first sodium-glucose co-transporter-2 inhibitor, approved by the US Food and Drug Administration for the treatment of type 2 diabetes mellitus. In this study, a sensitive UHPLC-MS/MS assay for rapid determination of canagliflozin in rat plasma was developed and validated for the first time. Chromatographic separation of canagliflozin and zafirlukast (IS) was carried out on Acquity BEH C18 column (100×2.1 mm, i.d. 1.7 µm) using acetonitrile-water (80:20, v/v) as mobile phase at a flow rate of 0.3 mL min(-1). Canagliflozin and IS were extracted from plasma by protein precipitation method using acetonitrile. The mass spectrometric detection was performed using electrospray ionization source in negative mode to avoid canagliflozin adduct ions formation. Multiple reaction monitoring were used for quantitation of precursor to product ion at m/z 443.16 >364.96 for canagliflozin and m/z 574.11>462.07 for IS, respectively. The assay was fully validated in terms of selectivity, linearity, accuracy, precision, recovery, matrix effects and stability. The validated method was successfully applied to the characterization of oral pharmacokinetic profiles of canagliflozin in rats. The mean maximum plasma concentration of canagliflozin of 1616.79 ng mL(-1) was achieved in 1.5 h after oral administration of 20 mg kg(-1) in rats.

Antiobesity potential of ursolic acid stearoyl glucoside by inhibiting pancreatic lipase

The present study was designed to evaluate the hypolipidemic effect of ursolic acid stearoyl glucoside (UASG) in high-fat diet-induced obesity. Two in vivo experiments such as high-fat diet-induced obesity mice model and lipid emulsion tolerance test in normal rats were performed. In vitro inhibition of pancreatic lipase activity was further measured to substantiate the results. In high-fat diet-induced obesity mice model, female Swiss mice were fed a high fat diet (HFD; 40% fat) with or without 1 or 2% of UASG or 0.012% orlistat for nine weeks. In lipid emulsion tolerance test male Wister rats were orally administered, lipid emulsion with or without 500 or 1000 mg/kg of UASG and the plasma triglycerides were measured from 0.5 to 5 h. Consumption of HFD containing UASG to mice for nine weeks exhibited significant reduction in lipid parameters, body weight, parametrial adipose tissue weight, liver triglyceride (TG) and different organ weight compared to HFD fed control. Further it was noted the improvement in insulin resistance induced by the HFD alone group. Furthermore, consumption of an HFD containing 1 or 2% of UASG significantly increased the fecal content and fecal triglyceride compared with the HFD group. Pre-treatment with UASG inhibited the elevated plasma triglyceride level after the oral administration of the lipid emulsion to rats. Further, UASG significantly inhibits activity of pancreatic lipase at a concentration of 2.5 mg/ml. Data obtained from the results indicated that UASG prevent high-fat diet-induced obesity in mice possibly by inhibiting pancreatic lipase activity.

Bioavailability enhancement and pharmacokinetic profile of an anticancer drug ibrutinib by self-nanoemulsifying drug delivery system.

The current studies were undertaken to enhance dissolution and bioavailability/pharmacokinetic profile of a newly approved anticancer drug ibrutinib (IBR) via encapsulation of drug into self‐nanoemulsifying drug delivery system (SNEDDS).

A simple and sensitive high performance liquid chromatography assay with a fluorescence detector for determination of canagliflozin in human plasma

Canagliflozin is the first sodium–glucose co-transporter-2 inhibitor approved for the treatment of type 2 diabetes mellitus. In this study, a simple and sensitive HPLC assay with a florescence detector was developed for accurate quantification of canagliflozin in human plasma using telmisartan as the internal standard (IS). Plasma samples were extracted by a liquid–liquid extraction method using diethyl ether as an extracting solvent. Chromatographic separation of canagliflozin and IS was performed on a Nucleodur Isis C18 column with an isocratic mobile phase of 20 mM potassium dihydrogen orthophosphate : acetonitrile (45 : 55, v/v) at a flow rate of 1 mL min−1. Canagliflozin and IS were eluted at 2.8 and 5.8 min, respectively, and detected at 280 and 325 nm for excitation and emission, respectively. The plasma calibration curve displayed excellent linearity over the concentration range of 16.13–6000 ng mL−1. The assay was fully validated in terms of selectivity & specificity, linearity of the calibration curve, accuracy & precision, recovery and stability under various storage conditions. To the best of our knowledge, this is the first validated HPLC-florescence detector assay for the quantification of canagliflozin in human plasma.

LC assay method for oxfendazole and oxyclozanide in pharmaceutical preparation

A method has been developed for the simultaneous determination of oxfendazole and oxyclozanide in a pharmaceutical preparation. The method involves reversed phase chromatography with isocratic elution of the mobile phase and detection at 300 nm. The range of quantification for oxfendazole and oxyclozanide was found to be 2-7 microg ml(-1) and 3-10 microg ml(-1), respectively. The validity of the method was evaluated in terms of linear regression analysis, precision, specificity and accuracy.

Treatment with aliskiren ameliorates tacrolimus-induced nephrotoxicity in rats

Introduction: Tacrolimus is frequently used as immunosuppressive agent in organ transplantation but its clinical use is limited due to its marked nephrotoxicity. Materials and methods: Male Wistar albino rats weighing 150–200 g (10–12 weeks old) were used. Animals were divided into four groups. Group 1 served as control group and received normal saline, group 2 served as toxic group and received 2 mg/kg tacrolimus i.p., group 3 served as treatment group and received 2 mg/kg tacrolimus i.p. followed by 2 mg/kg aliskiren orally and group 4 served as drug per se group and received 2 mg/kg aliskiren orally. Tacrolimus-induced nephrotoxicity was assessed biochemically and histopathologically. Results: Treatment with aliskiren decreased the tacrolimus-induced changes in biochemical markers of nephrotoxicity such as blood urea nitrogen and creatinine. Aliskiren also attenuated the effects of tacrolimus on oxidative stress parameters such as malondialdehyde, reduced glutathione and catalase. Histopathological and ultrastructural studies showed that aliskiren attenuated tacrolimus-induced renal damage. Conclusion: These results suggest that aliskiren has protective effects against tacrolimus-induced nephrotoxicity; implying that renin inhibitor may counteract nephrotic syndrome associated with immunosuppressant use.

Effects of Green Tea Extracts on the Pharmacokinetics of Quetiapine in Rats

Quetiapine is an atypical antipsychotic, used clinically in the treatment of schizophrenia, acute mania in bipolar disorders, and bipolar depression in adults. In this study, the effect of green tea extracts (GTE) on the pharmacokinetics of quetiapine (substrate of CYP3A4) was investigated in rats. Male Wistar albino rats received GTE (175 mg/kg) or saline (control) by oral gavage for 7 days before a single intragastric administration of 25 mg/kg quetiapine. Plasma concentrations of quetiapine were measured up to 12 h after its administration by a validated ultraperformance liquid chromatography-tandem mass spectroscopy. Pretreatment with GTE produced significant reductions in the maximum plasma concentration and area under the curve of quetiapine by 45% and 35%, respectively, compared to quetiapine alone. However, GTE did not produce significant change in elimination half-life and oral clearance of quetiapine. This study concluded that GTE may decrease the bioavailability of quetiapine when coadministered.

Development and validation of UHPLC-MS/MS assay for rapid determination of a carvone Schiff base of isoniazid (CSB-INH) in rat plasma: application to pharmacokinetic study

In this study, a fast UHPLC-MS/MS method was developed and validated for the determination of a novel potent carvone Schiff base of isoniazid (CSB-INH) in rat plasma using carbamazepine as an internal standard (IS). After a single-step protein precipitation by acetonitrile, CSB-INH and IS were separated on an Acquity BEH(TM) C18 column (50 × 2.1 mm, 1.7 µm) under an isocratic mobile phase, consisting of acetonitrile: 10 mM ammonium acetate (95:5, v/v), at a flow rate of 0.3 mL/min. Quantification was performed on a triple quadrupole tandem mass spectrometer in multiple reactions monitoring mode by using positive electrospray ionization source. The precursor to product ion transitions were set at m/z 270.08 → 79.93 for CSB-INH and m/z 237.00 → 178.97 for IS. The proposed method was validated in compliance with US Food and Drug Administration and European Medicines Agency guidelines for bioanalytical method validation. The method was found to be linear in the range of 0.35-2500 ng/mL (r(2)  ≥ 0.997) with a lower limit of quantification of 0.35 ng/mL. The intra- and inter-day precision values were ≤12.0% whereas accuracy values ranged from 92.3 to 108.7%. In addition, other validation results were within the acceptance criteria and the method was successfully applied in a pharmacokinetic study of CSB-INH in rats.