Tejal R. Gandhi

Antiurolithiatic activity of saponin rich fraction from the fruits of Solanum xanthocarpum Schrad. & Wendl. (Solanaceae) against ethylene glycol induced urolithiasis in rats

ETHNOPHARMACOLOGICAL RELEVANCE A well-known traditional herb Solanum xanthocarpum is widely used in India for the management of different ailments including urolithiasis. This study was designed to rationalize the use of Solanum xanthocarpum in kidney stone and to investigate its mechanism of action. MATERIALS AND METHODS The saponin rich fraction prepared from fruits of Solanum xanthocarpum (SXS) was evaluated for antiurolithiatic activity by in vitro and in vivo studies. In ethylene glycol (EG, 0.75% in drinking water for 28 days) induced urolithiasis model, two different experimental doses (20 mg/kg and 40 mg/kg, p.o., for 28 days) of saponin rich fraction were selected by dose fixation study. After 28 days, various biochemical parameters were measured in urine, serum and kidney homogenate. Kidneys were also subjected to histopathological analysis. RESULTS In vitro calcium oxalate crystal (CaOx) nucleation as well as aggregation was inhibited in artificial urine solution by SXS. The lithogenic treatment caused polyuria, damage renal function and oxidative stress, manifested as increased malondialdehyde, depleted reduced glutathione and decreased antioxidant enzyme catalase activities of the kidneys, which were prevented by simultaneous administration with SXS. Lithogenic treatment also caused crystalluria, hyperoxaluria, hypercalciuria, hypocitrauria, and hypomagnesaemia. Deposition of CaOx in renal tissue and cellular injury were seen in histopathology. Co-administration of SXS had potential to prevent these pathological changes due to lithogenic treatment. Moreover, SXS raised level of glycosaminoglycan, a stone inhibitor macromolecule found in urine which decreased. CONCLUSION The antiurolithiatic activity in Solanum xanthocarpum is mediated possibly through the inhibition of CaOx crystal formation and its effect on the urinary concentration of stone-forming constituents and nephrolithiasis inducing factors and this study rationalizes its medicinal use in urolithiasis.

Protective effect of aqueous extract of Oroxylum indicum Linn. (root bark) against DNBS-induced colitis in rats.

Objective: Aqueous root extract of Oroxylum indicum was evaluated in rats against dinitrobenzene sulfonic acid (DNBS) induced colitis. Materials and Methods: Rats were pre-treated orally for seven days and continued for four days after the induction of colitis with OIaq (100, 200, and 400 mg/kg) or vehicle. Colitis was induced by intracolonic instillation of 25 mg of DNBS per rat dissolved in 50% alcohol and 4 days later, the colonic mucosal damage was analyzed along with food intake, body weight, colon weight, spleen weight, histological damage, myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels, reduced glutathione (GSH), and nitric oxide levels in colonic tissue homogenate. Results: Significant reduction in gross damage area, weight loss and increase in colonic and spleen weight were evident in test substance-pretreated animals’ dose dependently as compared to vehicle treated control. These effects were confirmed biochemically by a reduction in colonic myeloperoxidase activity, malondialdehyde levels, nitric oxide levels, and increase in reduced glutathione (GSH) levels. Furthermore, microscopic examination revealed diminution of inflammatory cell infiltration and submucosal edema in colon segments of rats treated with OIaq. Conclusion: The results demonstrate the protective effect of OIaq in the animal model of acute colitis possibly through an antioxidant, anti-lipoperoxidative or due to reduction in nitric oxide generation.

Omeprazole improves the anti-obesity and antidiabetic effects of exendin-4 in db/db mice (-4 db/db)*.

Background:  In addition to its glucoregulatory actions, exendin‐4, a stable glucagon‐like peptide‐1 receptor agonist, exhibits protective effects in the pancreas and anti‐obesity effects. Suitable combination treatment with other anti‐obesity or pancreas protective agents would be an effective approach to optimize these additional effects. In the present study, we investigated the effects of the addition of omeprazole, a proton pump inhibitor, to exendin‐4 in db/db mice, an experimental model of obesity and type 2 diabetes.

Formulation and development of ophthalmic in situ gel for the treatment ocular inflammation and infection using application of quality by design concept

Abstract Context: The conventional liquid ophthalmic delivery systems exhibit short pre-corneal residence time and the relative impermeability to the cornea which leads to poor ocular bioavailability. Objective: The aim of this study was to apply quality by design (QbD) for development of dexamethasone sodium phosphate (DSP) and tobramycin sulfate (TS)-loaded thermoresponsive ophthalmic in situ gel containing Poloxamer 407 and hydroxyl propyl methyl cellulose (HPMC) K4M for prolonging the pre-corneal residence time, ocular bioavability and decreases the frequency of administration of dosage form. The material attributes and the critical quality attributes (CQA) of the in situ gel were identified. Central composite design (CCD) was adopted to optimize the formulation. Materials and methods: The ophthalmic in situ forming gels were prepared by cold method. Materials attributes were the amount of Poloxamer 407 and HPMC and CQA identified were Gel strength, mucoadhesive index, gelation temperature and % of drug release of both drug. Results and discussion: Optimized batch (F*) containing 16.75% poloxamer 407 and 0.54% HPMC K4M were exhibited all results in acceptable limits. Compared with the marketed formulation, optimized in situ gel showed delayed Tmax, improved Cmax and AUC in rabbit aqueous humor, suggesting the sustained drug release and better corneal penetration and absorption. Conclusion: According to the study, it could be concluded that DSP and TS would be successfully formulated as in situ gelling mucoadhesive system for the treatment of steroid responsive eye infections with the properties of sustained drug release, prolonged ocular retention and improved corneal penetration.

Combination of omeprazole with GLP-1 agonist therapy improves insulin sensitivity and antioxidant activity in liver in type 1 diabetic mice

BACKGROUND Combination with suitable pharmacological agents can improve the antiobesity and antidiabetic actions of glucagon like peptide-1 (GLP-1) based therapies. GLP-1 agonist exendin-4 may have insulin-independent effects on amelioration of insulin resistance and hepatic steatosis by virtue of its action on hepatic GLP-1 receptors, and these effects can be improved by combination with proton pump inhibitors. However, it was not assessed whether omeprazole can improve the peripheral actions of exendin-4 in the state of insulin deficiency. METHODS We investigated the effects of combination of omeprazole with GLP-1 agonist exendin-4 in multiple low-dose streptozotocin (STZ)-induced diabetes in C57BL/KsJ mice, a model of type 1 diabetes. Male diabetic mice were treated with exendin-4 and/or omeprazole for a period of 4 weeks. RESULTS Omeprazole treatment had no significant effect on lowering the blood glucose levels of diabetic mice, when compared to control, although it improved the antihyperglycemic actions of exendin-4. Similarly, serum triglycerides and total cholesterols levels were significantly lower in the combination treated mice compared to either exendin-4 and omeprazole alone. In addition, the combination treatment significantly ameliorated lipid peroxidation and hepatic triglycerides in diabetic mice compared to either exendin-4 and omeprazole alone. The improvement in hepatic insulin sensitivity, as indicated by insulin tolerance test (ITT) and pyruvate tolerance test (IPPTT), was correlated with the expression of nuclear factor erythroid-related factor 2 (Nrf2) and insulin receptor substrate-1 (IRS-1) and the combination treatment significantly improved the insulin sensitivity in comparison to vehicle control. CONCLUSION We conclude that combination with omeprazole improves the insulin sensitizing actions of GLP-1 therapy and these effects are partially mediated through the decrease in hepatic steatosis and improvement in antioxidant status in the liver.

Optimization of aceclofenac solid dispersion using Box-Behnken design: in-vitro and in-vivo evaluation.

The study investigates the combined influence of three independent variables in preparation of aceclofenac ternary solid dispersion (SD) by kneading method. A 3-factor, 3-level Box-Behnken design was used. Independent variables selected were microcrystalline cellulose (Avicel 200 = X1), hydroxypropyl methylcellulose-5 cps (HPMC E-5 = X2), and ratio of drug to polymer mixture (X3). Fifteen batches were prepared and evaluated for angle of repose and percentage drug release at 5 minutes (Q5). The transformed values of variables were subjected to multiple regression analysis to establish a second-order polynomial equation. Contour plots were constructed to evaluate the effects of X1, X2 and X3 on Q5 and angle of repose. Model was validated for accurate prediction of Q5 and angle of repose (AR) by performing checkpoint analysis. The computer optimization process and contour plots predict the levels of independent variables as X1= +0.5, X2 = -1 and X3 = +0.35 for maximized response of Q5 with better flow property. The stability study during 6 months confirms that aceclofenac exhibits high stability in solid dispersion. In vivo studies indicate that optimized ternary solid dispersion provides rapid pharmacological responses in mice and rats compared to marketed formulation.

Hepatoprotection through regulation of voltage dependent anion channel expression by Amomum subulatum Roxb seeds extract

Background and Purpose: Voltage dependent anion channel (VDAC) plays an important role in triggering the opening of the mitochondrial permeability transition pore (PTP) that leads to mitochondrial damage and induce apoptic or necrotic cell death. In the present study, the methanolic extract of Amomum subulatum Roxb. seeds (MEAS) was used to examine its effect on VDAC. Aminotransferase activity, mitochondrial membrane potential, calcium-induced liver MPT, and VDAC expression were used to evaluate the hepato protective effect of MEAS. Results: Pretreatment of mice with MEAS (100 and 300 mg/kg) significantly blocked the CCl4-induced increase in AST and ALT activities. Pretreatment with MEAS showed significant preservation of mitochondrial membrane potential as compared to CCl4 control demonstrating the mitochondrial protection. In addition, pretreatment with MEAS at various concentrations exerted a dose-dependent effect against sensitivity to mitochondrial swelling induced by calcium. In addition, MEAS (300 mg/kg) significantly increased the transcription and translation of VDAC. Conclusion: Our data suggest that MEAS significantly prevents the damage to liver mitochondria through regulation of VDAC expression.

Development and validation of an HPTLC method for the simultaneous estimation of Clonazepam and Paroxetine hydrochloride using a DOE approach

Abstract The present study examines simultaneous multiple response optimization using Derringers desirability function for the development of an HPTLC method to detect Clonazepam and Paroxetine hydrochloride in pharmaceutical dosage form. Central composite design (CCD) was used to optimize the chromatographic conditions for HPTLC. The independent variables used for the optimization were the n-butanol content in the mobile phase, the chamber saturation time and the distance travelled. HPTLC separation was performed on aluminium plates pre-coated with silica gel 60 F254 as the stationary phase using n-butanol:glacial acetic acid:water (9:2:0.5% v/v/v) as the mobile phase. Quantification was achieved based on a densitometric analysis of Clonazepam and Paroxetine hydrochloride over the concentration range of 40–240 ng/band and 300–1800 ng/band, respectively, at 288 nm. The method yielded compact and well-resolved bands at R f of 0.77 ± 0.02 and 0.34 ± 0.02 for Clonazepam and Paroxetine hydrochloride, respectively. The linear regression analysis for the calibration plots produced r 2 = 0.9958 and r 2 = 0.9989 for Clonazepam and Paroxetine hydrochloride, respectively. The precision, accuracy, robustness, specificity, limit of detection and limit of quantitation of the method were validated according to the ICH guidelines. The factors evaluated in the robustness test were determined to have an insignificant effect on the selected responses. The results indicate that the method is suitable for the routine quality control testing of marketed tablet formulations.

Development and characterization of novel hydrogel containing antimicrobial drug for treatment of burns

Introduction: The aim of burn management and therapy is fast healing and epithelisation to prevent infection. The present study is concerned with the development and characterization of a novel nanaoparticulate system; cubosomes, loaded with silver sulfadiazine (SSD) and Aloe vera for topical treatment of infected burns. Methods: Cubosome dispersions were formulated by an emulsification technique using different concentrations of a lipid phase Glyceryl Monooleate (GMO) and Poloxamer 407. The optimum formulae were incorporated in an aloe vera gel containing carbopol 934, to form cubosomal hydrogels (cubogels). The cubogels were characterized by in vitro release of SSD, rheological properties, pH, bioadhesion, Transmission Electron Microscopy and in-vivo Wound Healing Study. Results: The results show that the different concentration of GMO had significant effect on particle size, % EE and in vitro drug release. From the in-vitro drug release pattern and similarity factor (f2), it was concluded that batch CG3 (15% GMO and 1% P407) exhibited complete and controlled drug release within 12 hour (i.e. 98.25%), better bio adhesion and superior burn healing as compared to the marketed product. Conclusion: The in vivo burns healing study in rats revealed that the prepared optimized cubogel containing SSD and aloe vera has superior burns healing rate than cubogel with only SSD and marketed preparation so, it may be successfully used in the treatment of deep second degree burn.

Effect of Oroxylum indicum on intestinal motility in rodents

Oroxylum indicum is traditional herbal medicine in India, China and Japan used for its anti-diarrhoeal/anti-dysenteric activity, also found to be active against experimentally induced (DNBS induced) inflammatory bowel disease in rats with potential reduction in diarrhoea. It promotes us to evaluate effects of Oroxylum indicum on intestinal motility, both in vitro and in vivo, in rodents. Flavonoids rich fraction of O. indicum was obtained and the effect of extract on contraction of acetylcholine, barium chloride and electrical field stimulation was studied on isolated rabbit ileum. Anti-diarrhoeal activities were investigated using castor oil and magnesium sulphate-induced diarrhoeal models in mice. Effect on intestinal motility was studied using gastrointestinal motility and antienteropooling assay methods. Antimicrobial activity of extract was evaluated using disc diffusion assay method. Extract inhibited the contractions induced by acetylcholine, barium chloride and electrical field stimulation. Verapamil potentiates inhibitory effect of extract. Extract showed significant and dose-dependent anti-diarrhoeal effect devoid of altering gastrointestinal motility in normal animals. It also inhibited the microbial growth in disc diffusion assay method. Extract normalized intestinal motility altered by inflammatory stimulus and possesses antidiarrhoeal activity. Alteration of intestinal motility may involve modification in L-type Ca2+ channels.