Role of cytochrome epoxygenase (CYP2J2) in the pathophysiology of coronary artery disease in South Indian population.

BACKGROUND: The cytochrome P-450 2J2 (CYP2J2) is known to be one of the major enzymes of epoxygenase pathway of arachidonic acid in extrahepatic tissues, which produces series of regioisomeric cis-epoxyeicosatrienoic acids (EETs) such as 5,6-, 8,9-, 11,12-, and 14,15-EETs. In the present study, we analyzed the impact of a genetic variant in CYP2J2 on coronary artery disease (CAD) in the Telangana region of Indian population. MATERIAL AND METHODS: The case-control study consisted of 100 CAD cases and 110 healthy controls. The deoxyribonucleic acid was extracted using the salting out method. Genotyping and gene expression was performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism and real-time-PCR methods. RESULTS: In the present study, the percentage of smokers, alcoholics, hypertensive patients, and diabetics was high. Increase in fasting glucose, urea, creatinine, fasting triglycerides, total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), total cholesterol/high-density lipoprotein (TC/HDL), LDL/HDL, homocysteine, and C-reactive protein levels were significantly higher in patients with CAD than in controls (p < 0.001). CYP2J2 G-50T was associated with CAD (p = 0.04). The mRNA expression of CYP2J2 showed altered gene expression in this study among CAD patients in comparison with control (p = 0.01). CONCLUSIONS: A functionally relevant polymorphism of the CYP2J2 gene was independently associated with an increased risk of CAD.

Pharmacodynamic and cytogenetic evaluation in CYP2C19*2 and CYP2C19*3 allelomorphism in South Indian population with clopidogrel therapy.

BACKGROUND: Genetic factors play a significant role in pathogenesis of most diseases of heart. The present study was undertaken to correlate coronary artery disease with demographical, biochemical alterations, SNPs, gene expression and chromosomal abnormalities and for further enlightening the investigation in this field. METHODS: 150 patients taking clopidogrel drug were selected and single nucleotide polymorphism was done by PCR-RFLP techniques. With the same patients cytogenetic analysis was carried out on leukocyte cultures by karyotyping. Gene expression studies for 20 CAD patients and normal controls were done by RT-PCR techniques. RESULTS: In this study of patients with coronary artery disease the frequencies of the Extreme Metabolizers, Intermediate Metabolizers in CYP2C19*2 (rs4244285) were present in 90% and 10% but no Poor Metabolizers were found in this allele. The frequencies of Extreme Metabolizer, Intermediate Metabolizer and Poor Metabolizer in CYP2C19*3 (rs4986893) were present in 41%, 50% and 9% respectively. Among 20 CAD samples, 13 of 20 (65%) showed CYP2C19 gene over expression in CAD patients and all controls showed normal expression. Among the 150 CAD patients, 145 had normal karyotype, only five patients showed change in normal karyogram carried out by leukocyte culture. CONCLUSION: Genetic testing of CYP2C19 may help in prescribing a dose according to genetic makeup and represent the initial steps towards the development of diagnostic tests and therapeutic strategies that will substantially improve human health. This study highlights the progress that has been made in using pharmacogenomic and gene expression analysis, cardiovascular genomic research and the potential for applying these findings in clinical medicine.

The protective effects of zinc in lead-induced testicular and epididymal toxicity in Wistar rats.

The aim of this study was to investigate the beneficial effects of zinc (Zn) in preventing lead (Pb)-induced reproductive toxicity in Wistar rats. The rats were divided into four groups, namely, control group, Pb group, Zn group, and Pb + Zn group. Animals were exposed to Pb (819 mg of Pb/L) or Zn (71 mg of Zn/L) or both through drinking water for 65 days. Rats exposed to Pb showed decreased weights of testes and accessory sex organs. Significant decrease in the testicular daily sperm production, epididymal sperm count, motility, viability, and number of hypoosmotic tail coiled sperm was observed in Pb-exposed rats. Testicular 3ß- and 17ß-hydroxysteroid dehydrogenase activity levels and circulatory testosterone levels were also decreased significantly in Pb-exposed rats. A significant increase in the lipid peroxidation products with a significant decrease in the activities of catalase and superoxide dismutase were observed in the testes and epididymis of Pb-exposed rats. Moreover, the testicular architecture showed lumens devoid of sperm in Pb-exposed rats. Supplementation of Zn mitigated Pb-induced oxidative stress and restored the spermatogenesis and steroidogenesis in Pb-exposed rats. In conclusion, cotreatment of Zn is effective for recovering suppressed spermatogenesis, steroidogenesis, elevated oxidative status, and histological damage in the testis of rats treated with Pb.

Protective effects of resveratrol against cisplatin-induced testicular and epididymal toxicity in rats.

This study investigated the probable protective effect of resveratrol against cisplatin-induced testicular and epididymal toxicity in rats. Body weights of the animals showed no significant changes after cisplatin administration. Conversely, the weights of testis, and accessory sex organs reduced significantly. The daily sperm production and epididymal sperm quantity and quality were decreased in cisplatin treated rats. The circulatory levels of testosterone and activity levels of testicular 3ß-hydroxysteroid dehydrogenase and 17ß-hydroxysteroid dehydrogenase were significantly decreased after cisplatin treatment. The activity levels of superoxide dismutase and catalase were decreased with an increase in the levels of lipid peroxidation and H2O2 generation in the testis and epididymis of cisplatin treated rats, suggesting the cisplatin-induced oxidative stress. The biochemical findings were supplemented by histological examination of testis. Reduced tubular size, decreased spermatogenesis and deterioration in architecture were observed after cisplatin treatment. Administration of resveratrol alone has no significant effect on testicular and epididymal metabolism. On the other hand, administration of resveratrol ameliorated cisplatin-induced alterations in testicular and epididymal oxidative damage, suppressed steroiodgenesis and spermatogenesis and restored testicular architecture. In conclusion, resveratrol possesses multimechanistic protective activity that can be attributed to its steroidogenic and antioxidant actions.

Role of melatonin in mitigating chemotherapy-induced testicular dysfunction in Wistar rats.

Testicular cancer is the most common cancer affecting men of reproductive age, and its incidence is increasing steadily. A regimen of cisplatin (P), vinblastin (V) and bleomycin (B) (PVB) is the standard chemotherapy for testicular cancer. Though PVB-based chemotherapy has been widely used against germ cell tumors, it is associated with induction of oxidative toxicity and a transient or permanent loss of fertility. However, the mechanism of action of PVB on the testis is not thoroughly elucidated. Using a rat model, we investigated the persistence of the effects of PVB on steroidogenesis, spermatogenesis and testicular oxidative status and architecture. Further, we have also studied whether administration of melatonin has any protective effect on testicular physiology in the PVB-treated rats, since melatonin exerts influence on the antioxidant defense system. The body weight of the PVB-treated rats did not show significant change as compared with the control group. Significant decrease in the weight of the testis was observed with a reduction in volume in the PVB-treated rats. Administration of PVB caused a reduction in the testicular steroidogenesis and spermatogenesis. The circulatory levels of testosterone were also significantly reduced with an elevation of FSH and LH in the PVB-treated rats. Testicular architecture was severely affected with a reduction in seminiferous tubule diameter and epithelial height. The activities of superoxide dismutase and catalase were decreased while the levels of lipid peroxidation increased significantly in the testis of the PVB-treated rats indicating depletion of antioxidant defence system and elevation of oxidative stress. Co-administration of melatonin mitigated these changes in the PVB-treated rats.

Testicular and epididymal toxicity induced by benzo(a)pyrene, alcohol, and their combination in Wistar rats.

Alcoholism and cigarette smoking are pervasive problems that have been implicated in human health. In this study, independent and combinative toxicities of alcohol and benzo(a)pyrene (BaP) were tested for reproductive toxicity in rats. Male Wistar rats were exposed to BaP (100 µg per kg body weight) on alternative days and alcohol (2 g per kg body weight per day) daily, either individually or in combination for 60 days. Exposure to BaP or alcohol significantly decreased the fertility index and reduced the number of implantations associated with elevated pre- and post-implantation losses. The relative weights of testes, epididymis, seminal vesicles, and prostate gland were significantly decreased in BaP or alcohol administered rats. Exposure to BaP or alcohol significantly decreased daily sperm production, sperm density, percentages of motile, viable, HOS-tail swelled sperm, testicular 3ß- and 17ß-hydroxysteroid dehydrogenase activity levels, mRNA levels of steroidogenic acute regulatory protein, and serum testosterone levels. Further, in silico studies revealed the binding of BaP at the hydrophobic tunnel of StAR protein. Additional studies disclosed stable interactions of BaP with the amide group of ASN150 and the hydroxyl group of THR263 by forming three hydrogen bonds. Our results also showed that treatment of rats with BaP or alcohol caused a marked increase in levels of superoxide anions, hydrogen peroxide, and lipid peroxidation in testis and epididymis. Conversely, glutathione levels and activity levels of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase in testis as well as epididymis decreased significantly in the experimental rats. Under the same conditions, increased fragmented DNA levels were observed in sperm. The results of the present study indicate that exposure to BaP or alcohol adversely affected the male reproductive functions, which may be, at least in part, due to androgen deficiency and/or oxidative stress-related mechanisms. Consistently, the present results also showed higher reproductive toxicity upon exposure to combinations of BaP and alcohol than upon their individual treatments. Therefore, this combination was classified as additive and synergistic responses of BaP and alcohol.

Lead aggravates the diabetic-induced reproductive toxicity in male Wistar rats.

Diabetes, an unresolved metabolic disorder, and lead contamination are prevalent problems in contemporary society. Previously, we have reported that either diabetes or lead exposure resulted in reproductive toxicity in male Wistar rats. The aim of this study was to evaluate whether diabetic rats exposed to lead demonstrate a higher degree of reproductive toxicity when compared with lead-exposed control rats. Diabetes was induced by injecting a single dose of streptozotocin (50 mg per kg body weight). Control and diabetic rats were exposed to lead at a concentration of 819 mg L-1 (0.15% lead acetate) through drinking water for a period of 30 days and assessed for reproductive and oxidative end points. The relative weights of the testes, epididymis, seminal vesicles, and the prostate gland were significantly decreased in diabetic rats. Daily sperm production, epididymal sperm count, motile, viable and HOS-tail swelled sperms, serum testosterone levels and testicular 3ß- and 17ß-hydroxysteroid dehydrogenase activity levels were significantly decreased in diabetic rats. Significant reductions in testicular and epididymal antioxidant enzyme activity levels and glutathione levels were observed in diabetic rats with an elevation in the levels of superoxide anions, hydrogen peroxides, and lipid peroxidation. A significant reduction in the number of implantations associated with elevated pre- and post-implantation losses was observed in females mated with diabetic males. Mild histopathological malformations were observed in the testis of the diabetic rats. Similar reproductive and oxidative toxicities were observed in lead-exposed control rats. Furthermore, lead exposed diabetic rats showed additional deterioration in reproductive end points and a noteworthy elevation in oxidative toxicity, suggesting that treatment with lead exacerbates reproductive toxicity in streptozotocin-induced diabetic rats.

Melatonin reduces oxidative stress and restores mitochondrial function in the liver of rats exposed to chemotherapeutics.

This study was undertaken to investigate whether administration of melatonin protects PVB-Induced oxidative and metabolic toxicity in the liver of Wistar rats. Adult male Wistar rats were intraperitoneally injected with either melatonin or PVB (cisplatin, vinblastine, and bleomycin) alone or combination for a period of 9 weeks. A significant increase in lipid peroxidation levels and decrease in catalase and superoxide dismutase activity levels were observed in the liver mitochondria of rats treated with PVB indicating increased oxidative stress. PVB treatment significantly decreased the succinate dehydrogenase activity with a significant increase in lactate dehydrogenase, glucose-6-phosphate dehydrogenase, aspartate aminotransaminase, alanine aminotransaminase, and glutamate dehydrogenase activities indicating deranged hepatic metabolism. Melatonin administration, on the other hand was found to significantly improve PVB-Induced biochemical changes, bringing them closer to the controls. The results from the study provide evidence that treatment with PVB affects hepatic metabolism in rats by inducing oxidative stress followed by decreasing mitochondrial oxidation and also point towards the clinical potential of melatonin as an adjuvant therapy to conventional chemotherapeutic regimens.

In vitro quantitative and relative gene expression analysis of pancreatic transcription factors Pdx-1, Ngn-3, Isl-1, Pax-4, Pax-6 and Nkx-6.1 in trans-differentiated human hepatic progenitors.

AIMS/INTRODUCTION: Diabetes is a major health concern throughout the world because of its increasing prevalence in epidemic proportions. ß-Cell deterioration in the pancreas is a crucial factor for the progression of diabetes mellitus. Therefore, the restoration of ß-cell mass and its function is of vital importance for the development of effective therapeutic strategies and most accessible cell sources for the treatment of diabetes mellitus. MATERIALS AND METHODS: Human fetuses (12-20 weeks gestation age) were used to isolate human hepatic progenitor cells (hHPCs) from fetal liver using a two-step collagenase digestion method. Epithelial cell adhesion molecule-positive (EpCAM+ve)-enriched hHPCs were cultured in vitro and induced with 5-30 mmol/L concentration of glucose for 0-32 h. Pdx-1 expression and insulin secretion was analyzed using immunophenotypic and chemifluorescence assays, respectively. Relative gene expression was quantified in induced hHPCs, and compared with uninduced and pancreatic cells to identify the activated transcription factors (Pdx-1, Ngn-3, Isl-1, Pax-4, Pax-6 and Nkx-6.1) involved in ß-cell production. RESULTS: EpCAM+ve cells derived from human fetal liver showed high in vitro trans-differentiation potential towards the ß-cell phenotype with 23 mmol/L glucose induction after 24 h. The transcription factors showed eminent expression in induced cells. The expression level of transcription factors was found significantly high in 23 mmol/L-induced hHPCs as compared with the uninduced cells. CONCLUSIONS: The present study has shown an exciting new insight into ß-cell development from hHPCs trans-differentiation. Relative quantification of gene expression in trans-differentiated cells offers vast possibility for the production of a maximum number of functionally active pancreatic ß-cells for a future cure of diabetes.

Protective role of Centella asiatica on lead-induced oxidative stress and suppressed reproductive health in male rats.

Centella asiatica has been mentioned in ancient ayurvedic text of the Indian system of medicine for its properties to promote intelligence. The objective of the present study was to investigate the beneficial effects of C. asiatica on lead-induced oxidative stress and suppressed reproductive performance in male rats. Significant decrease in the weights of testes and epididymis were observed in lead treated animals. Exposure to lead acetate significantly increased malondialdehyde levels with a significant decrease in the superoxide dismutase and catalase activities in the liver, brain, kidneys and testes of rats. Epididymal sperm count, viable sperms, motile sperms and HOS-tail coiled sperms decreased significantly in lead-exposed rats. Testicular steroidogenic enzyme activities also decreased significantly in lead-exposed rats. No significant changes in the selected reproductive variables were observed in the plant extract alone treated rats. Whereas, co-administration of aqueous extracts of C. asiatica to lead exposed rats showed a significant increase in the weights of reproductive organs, reduction in lead-induced oxidative stress in the tissues and improvement in selected reproductive parameters over lead-exposed rats indicating the beneficial role of C. asiatica to counteract lead-induced oxidative stress and to restore the suppressed reproduction in male rats.

Protective effects of selenium on fluoride induced alterations in certain enzymes in brain of mice.

This study reports the protective effects of selenium on fluoride induced alterations in the activities of pro-oxidative (xanthine oxidase (XOD), lipid peroxidation (LPO) free radical scavenging, [catalase, superoxide dismutase (SOD), glutathione-s-transferase (GST), glutathione peroxidase (GPX), glutathione reductase (GR), glutathione) and metabolic (glucose-6-phosphate dehydrogenase, alanine amino transferase (ALAT), aspartate aminotransferase (AAT), creatine phosphokinase (CPK), acid phosphatase (AP), alkaline phosphatase (ALP)] enzymes along with fluoride and selenium levels in brain of mice. Animals were divided into control, NaF treated group (20 mg kg(-1) body wt.(-1) intraperitonial) and Selenium+NaF treated group (sodium selenite, 5 microg of selenium/0.2 ml distilled water kg(-1) body wt.(-1) day) and were maintained for 14 days on respective treatments. The decreased bodyweight (-11.35%) as well as organosomatic index (-15.1%) of brain in NaF group were recovered in treatment of selenium along with NaF. The increased accumulation of fluoride (32.1%) in brain observed in NaF treated group compared to control was diminished in selenium+NaF treated group. Selenium levels (3.03%) increased in selenium+NaF treated group in compared to decrement in NaF treatment. The SOD (-16.6%), Catalase (-21.5%), GST(-13.72%), GPX (-19.16%), GR (-44.97%) activities and Glutathione (-23%) content in NaF treated group were decreased significantly compared to controls, which were significantly (p < 0.01) recovered in selenium+NaF group. Increased XOD (10.85%) and LPO (8.61%) levels observed in brain of NaF treated mice were reversed with selenium treatment. Glucose-6-phosphate dehydrogenase (-46.98%), ALAT (-10.44%), AAT (-10.21%), CPK (-27.98%) were decreased and alkaline phosphatase (10.6%), acid phosphatase (24.09%) increased in brain of mice after administration of NaF. All metabolic enzymes were significantly (p < 0.01) reversed after administration of selenium to the NaF treated group. Thus, the adverse effects of NaF on oxidative and metabolic enzymes of brain were reversible with ameliorative action of selenium supplementation. As evident in this study the antioxidative nature of selenium coupled with its reversal effect on metabolic enzymes in brain of mice treated with fluoride suggests its use as antidote agent against fluorosis.

Post natal antioxidant enzyme activity of rat brain regions during developmental lead exposure.

This study reports the effects of low level developmental Pb exposure on specific brain regions like hippocampus, cerebellum and cerebral hemispheres of antioxidant enzyme activities. Wistar dams were exposed to 50 ppm, 100 ppm and 500 ppm of Pb acetate in drinking water during pregnancy and lactation (gestation day 6 through PND 21 (post natal day) and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) were determined in the hippocampus, cerebellum and cerebral hemispheres of pups during treatment period (PND 7, 14, and 21 days) and also during withdrawl period (PND 35, 45, 60 and 90 days). During treatment period, SOD activity significantly (p < 0.05) decreased in all regions of all the treated groups with maximum decrease in 500 ppm treated group of 21 days, while GSH-Px and GR activities increased with maximum increase in 21 days aged 500 ppm group. During withdrawl period, the activities of all enzymes were significantly (p < 0.05) reversed. Thus the perinatal exposure of dams to variable dosages of low level lead results in characteristic neurochemical alterations in rat brain regions due to impaired antioxidants function.