Minocycline-preconditioned neural stem cells enhance neuroprotection after ischemic stroke in rats

Transplantation of neural stem cells (NSCs) offers a novel therapeutic strategy for stroke; however, massive grafted cell death following transplantation, possibly due to a hostile host brain environment, lessens the effectiveness of this approach. Here, we have investigated whether reprogramming NSCs with minocycline, a broadly used antibiotic also known to possess cytoprotective properties, enhances survival of grafted cells and promotes neuroprotection in ischemic stroke. NSCs harvested from the subventricular zone of fetal rats were preconditioned with minocycline in vitro and transplanted into rat brains 6 h after transient middle cerebral artery occlusion. Histological and behavioral tests were examined from days 0-28 after stroke. For in vitro experiments, NSCs were subjected to oxygen-glucose deprivation and reoxygenation. Cell viability and antioxidant gene expression were analyzed. Minocycline preconditioning protected the grafted NSCs from ischemic reperfusion injury via upregulation of Nrf2 and Nrf2-regulated antioxidant genes. Additionally, preconditioning with minocycline induced the NSCs to release paracrine factors, including brain-derived neurotrophic factor, nerve growth factor, glial cell-derived neurotrophic factor, and vascular endothelial growth factor. Moreover, transplantation of the minocycline-preconditioned NSCs significantly attenuated infarct size and improved neurological performance, compared with non-preconditioned NSCs. Minocycline-induced neuroprotection was abolished by transfecting the NSCs with Nrf2-small interfering RNA before transplantation. Thus, preconditioning with minocycline, which reprograms NSCs to tolerate oxidative stress after ischemic reperfusion injury and express higher levels of paracrine factors through Nrf2 up-regulation, is a simple and safe approach to enhance the effectiveness of transplantation therapy in ischemic stroke.     

Mini-vesicostomy in the management of PUV after valve ablation

AimTo determine the usefulness of infra-umbilical mini-vesicostomy in infants with posterior urethral valves (PUV), in developing countries. This new technique facilitates clean intermittent catheterization (CIC) and overnight bladder drainage, which have been effectively used for the treatment of valve bladders in the developed world.MethodsA retrospective analysis of the records of three infants who underwent a mini-vesicostomy between 2005–2009 was done. All were put on CIC in the neonatal period. Monitoring of renal parameters, bladder function and structural changes in the bladder was done before and after 4 years of CIC.ResultsAll three showed a decrease in upper tract dilatation, improvement in cortical function and improvement of bladder compliance at the end of 4 years. Two patients are on CIC through vesicostomy and can pass a good stream of urine per urethraly, and in one the vesicostomy has been closed.ConclusionMini-vesicostomy is a useful option to allow CIC on a long-term basis in children with PUV. There were no complications with this technique in this small group of patients, and it has been well accepted by their families.     

A p.R870H mutation in the beta-cardiac myosin heavy chain 7 gene causes familial hypertrophic cardiomyopathy in several members of an Indian family

Familial hypertrophic cardiomyopathy is an autosomal dominant genetic disorder characterized mainly by left ventricular hypertrophy and myocyte disarray; it is the most common cause of sudden death in otherwise healthy individuals. More than 270 mutations in genes encoding the cardiac sarcomere have been identified. Attempts to establish a genotype-phenotype correlation for each of the mutations have not been highly successful. It has been suggested that additional genetic loci, as well as nongenetic factors such as lifestyle, gender and age, may play a role in modulating the clinical presentation of the disease. The p.R870H mutation has been identified as the cause of familial hypertrophic cardiomyopathy in an Indian family. The results indicate that the disease phenotype varied among various affected members of the family, and the variation may be attributed to factors, such as gender and gene dosage.     

Modulation of antioxidant defense system by the environmental fungicide carbendazim in Leydig cells of rats

Carbendazim (methyl-2-benzimidazole carbamate, MBC) a metabolite of benomyl is one of the most widespread environmental contaminant of major concern to human and animal reproductive health. The present investigation was undertaken to study the impact of carbendazim exposure on Leydig cell functions. Adult albino male rats of the Wistar strain were administered with carbendazim (25 mg/(kg (body weight)/day)) orally for 48 days. The control animals received vehicle (corn oil) alone. Another group of rats were treated with carbendazim and the same was withdrawn for a further period of 48 days. After the treatment period, rats were euthanized and blood was collected for the assay of serum hormones such as luteinizing hormone (LH), prolactin (PRL), testosterone and estradiol. Testes were immediately removed and Leydig cells were isolated in aseptic condition. Purified Leydig cells were used for quantification of steroidogenic enzymes such as 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β-HSD). Leydig cellular enzymatic antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), γ-glutamyl transpeptidase (γ-GT), glucose-6-phosphate dehydrogenase (G6PDH) and non-enzymatic antioxidants such as reduced glutathione (GSH), -tocopherol (vitamin E), ascorbic acid (vitamin C) and β-carotene (vitamin A) were assayed. Lipid peroxidation (LPO) and reactive oxygen species (ROS) were also quantified. Carbendazim exposure had no effect on body weight, serum LH and prolactin. However, testis weight, serum testosterone and estradiol were significantly decreased. In addition to this, Leydig cellular activities of steroidogenic enzymes such as 3β-HSD, 17β-HSD, antioxidant enzymes SOD, CAT, GPx, GR, GST, γ-GT, G-6-PDH and non-enzymatic antioxidants such as GSH, vitamins E, C and A were significantly diminished, whereas LPO and ROS were markedly elevated. All these above-mentioned parameters from the animals after withdrawal of MBC treatment were similar to those of the control group. Thus, the present study suggests that chronic low dose treatment of MBC is capable of inducing reproductive toxicity through increased oxidative stress, but is transient and reversible upon withdrawal of treatment.     

Design and statistical optimization of glipizide loaded lipospheres using response surface methodology

A 32 factorial design was employed to produce glipizide lipospheres by the emulsification phase separation technique using paraffin wax and stearic acid as retardants. The effect of critical formulation variables, namely levels of paraffin wax (X1) and proportion of stearic acid in the wax (X2) on geometric mean diameter (dg), percent encapsulation efficiency (% EE), release at the end of 12 h (rel12) and time taken for 50% of drug release (t50), were evaluated using the F-test. Mathematical models containing only the significant terms were generated for each response parameter using the multiple linear regression analysis (MLRA) and analysis of variance (ANOVA). Both formulation variables studied exerted a significant influence (p < 0.05) on the response parameters. Numerical optimization using the desirability approach was employed to develop an optimized formulation by setting constraints on the dependent and independent variables. The experimental values of dg, % EE, rel12 and t50 values for the optimized formulation were found to be 57.54 +/- 1.38 mum, 86.28 +/- 1.32%, 77.23 +/- 2.78% and 5.60 +/- 0.32 h, respectively, which were in close agreement with those predicted by the mathematical models. The drug release from lipospheres followed first-order kinetics and was characterized by the Higuchi diffusion model. The optimized liposphere formulation developed was found to produce sustained anti-diabetic activity following oral administration in rats.