Gayathri M Rao

Resveratrol improves postnatal hippocampal neurogenesis and brain derived neurotrophic factor in prenatally stressed rats

Prenatal stress induced neuronal dysfunction is multifactorial, including suppressed neurogenesis in developing brain. Resveratrol is known to exert its neuroprotective potential by enhancing neurogenesis. But the efficacy of resveratrol against prenatal stress was not addressed in detail. Hence in the present study we evaluated the neuroprotective action of resveratrol on prenatal stress‐induced impaired neurogenesis. Pregnant rats were subjected to restraint stress during early or late gestational period. Another sets of rats received resveratrol during entire gestational period along with early or late gestational stress. The study parameters included neuronal assay of doublecortin positive neurons (DCX +ve) and brain derived neurotrophic factor (BDNF) estimations in 40th postnatal day rat brain. Both early and late gestational stress resulted in significant decrease in generation of new born neurons and BDNF expression in hippocampus. The decrease in number of DCX +ve neurons and hippocampal BDNF expression was more profound in the offspring who received late gestational stress compared to early gestational stress. Resveratrol treatment has improved the expression of DCX +ve neurons and BDNF expression. These data suggest the neuroprotective efficacy of resveratrol against prenatal stress induced impaired neurogenesis.

Role of antioxidant enzymes in brain tumours

Erythrocyte antioxidant enzymes were analysed in 100 patients with intracranial neoplasm and in 47 controls. There was a significant decrease in RBC glutathione reductase (GRx) and superoxide dismutase (SOD) activity in most types of brain tumor cases. Patients with acoustic neurinoma showed a significant reduction in selenium-dependent glutathione peroxidase (Se-GPx) activity. A decrease in catalase (CT) activity was seen in most of the brain tumor patients but remained statistically insignificant when compared to controls. A significant increase in plasma ceruloplasmin concentration was observed in patients with glioma. These enzymes were also studied in 27 post-treatment cases. GRx activity returned to normal levels in these patients. RBC SOD and plasma ceruloplasmin levels showed a tendency to return to normal. Hence, a marked decrease in the antioxidant enzymes may have a role in the genesis of considerable oxidative stress in patients with brain tumors.

Neuroprotective effect of resveratrol against prenatal stress induced cognitive impairment and possible involvement of Na+, K+-ATPase activity

Resveratrol, an active ingredient of red wine extracts, has been shown to exhibit neuroprotective effects in several experimental models. Hence in the present study, the protective effects of resveratrol on cognitive deficits induced by prenatal stress were evaluated in offspring, and the possible involvement of Na(+), K(+)-ATPase in learning deficits were explored. Pregnant rats were subjected to restraint stress during early or late gestational period. Another set of rats received resveratrol during the entire gestational period along with early or late gestational stress. The study parameters included various behavioral tests like open field test and Morris water maze test. At the end of the behavioral tests (on 40th postnatal day), the offspring were sacrificed, and their brain homogenate was subjected to Na(+), K(+)-ATPase estimation. Early and late gestational stress affected spatial learning and memory and prenatal resveratrol has reversed these cognitive deficits. The Na(+), K(+)-ATPase activity in the offspring brain homogenate was reduced in the late gestational stress group; however prenatal resveratrol treatment has not affected this activity. These data suggest the neuroprotective efficacy of resveratrol against prenatal stress induced cognitive impairment. Though late gestational stress involves Na(+), K(+)-ATPase activity in rat brain homogenate, this would not be the primary cause in prenatal stress-induced cognitive dysfunction.

Plasma antioxidant vitamins and lipid peroxidation products in pregnancy induced hypertension.

It has been suggested that antioxidant systems are impaired in pregnancy induced hypertension and hence patients are exposed to oxidative stress. In order to investigate the relationship between lipid peroxidation and certain antioxidant parameters in blood of pregnancy induced hypertension (PIH) cases, 25 normotensive and 23 PIH samples were studied. In the present study, thiobarbituric acid reactive substances showed a tendency to increase, however the increase remained statistically insignificant. Plasma ascorbic acid level remained unaltered and Vitamin E showed a tendency to increase in the study group. The findings implicate oxidative stress in the disease and cite the biochemical rationale for clinical trials of antioxidants to prevent and treat pregnancy induced hypertension.

Resveratrol for Prenatal-Stress-Induced oxidative damage in growing brain and its consequences on survival of neurons

Abstract Background: Prenatal-stress-induced neuronal damage in offspring is multifactorial, including oxidative damage in the developing brain. Resveratrol is known to exert its neuroprotective potentials by upregulating several antioxidant systems. Hence, the study was undertaken to evaluate the neuroprotective effect of resveratrol against prenatal-stress-induced hippocampal damage and oxidative damage in neonate rat brains. Methods: Pregnant rats were subjected to restraint stress during early or late gestational period. Another set of rats received resveratrol during the entire gestational period along with early or late gestational stress. The study parameters included several antioxidant studies directly from rat brain homogenate on the 40th postnatal day and hippocampal neuronal assay on the 21st postnatal day. Results: Early as well as late gestational stress resulted in a significant increase in lipid peroxidation and advanced oxidation protein products and decrease in total antioxidant activity and nitric oxide levels in rat brain homogenate. The neurons of the dentate gyrus were severely affected in early and late gestational stress, and only the neurons of the CA3 region were adversely affected in late gestational stress. Administration of resveratrol reversed the prenatal-stress-induced oxidative damage and neurons of dentate gyrus but not the CA3 hippocampal neurons. Conclusions: These results show the neuroprotective abilities of resveratrol against prenatal-stress-induced oxidative damage in neonatal rat brain.

Evaluation of knowledge of and attitudes toward epilepsy among the health science students of Manipal University

This study was carried out to assess the knowledge, attitudes, and practices with respect to epilepsy among health science students of Manipal University. The study was conducted among first-year health science students of Kasturba Medical College on the Manipal and Mangalore campuses of Manipal University. All students willing to participate (n=587) were asked to answer a standardized questionnaire on epilepsy. Our study group included educated urban people from various ethnic backgrounds of various countries who chose health science as a career, which makes the study different from others. Even though most of the students had heard about epilepsy, very few knew about the underlying cause. Most of the students were ignorant about the drugs and ways to deal with epileptic seizures. Questions related to community and religion were deliberately avoided as some subjects found such questions offensive, which may have resulted in a difference in response as compared with previously published studies. It was observed that a large number of students were not aware of the nuances of epilepsy. However, we expect the knowledge, attitudes and awareness to improve considerably with time and increased exposure. These findings support a need to promote epilepsy awareness programs as a means of increasing public knowledge of epilepsy.

Diaphragmatic breathing exercise as a therapeutic intervention for control of oxidative stress in type 2 diabetes mellitus

Present study aims to evaluate the effect of diaphragmatic breathing on anthropometry, blood pressure, glycemic control and oxidative stress in patients with type 2 diabetes on standard care in comparison with standard care alone. Study involved 123 patients who were assigned to receive either standard care or with additional diaphragmatic breathing for 3 months. In comparison with the control group, diaphragmatic breathing resulted in significant reduction in body mass index, waist-hip ratio, fasting and post prandial plasma glucose, glycated hemoglobin, malondialdehyde, superoxide dismutase and improvement in glutathione and vitamin C. There was no difference in waist circumference, blood pressure and vitamin E in intervention group at follow-up. It can be concluded that diaphragmatic breathing can be employed as an effective therapy in reducing the oxidative stress while it can be incorporated as an add-on therapy to standard care in improving the anthropometry and glycemic parameters in type 2 diabetes.

Effects of Acorus calamus Rhizome Extract on the Neuromodulatory System in Restraint Stress Male Rats.

AIM Prolonged exposure to stress mainly affects the cognitive functions of the brain by inducing neuronal damage mediated through oxidative stress. Acorus calamus (AC) has long been used in Indian folk medicine for various central nervous system (CNS) abnormalities. Hence the present study investigates the effect AC on learning and memory in rats. MATERIAL AND METHODS Adult Wistar male rats were subjected to restrained stress for 21 days (6 hr/day) and the animals were concurrently administered AC for 21 days orally. The Hebb-Williams maze and elevated plus maze served as standard behavioural models for testing memory. The rats were sacrificed on 22nd day and the brain homogenate was taken for various biochemical assessments. RESULTS Sodium potassium ATPase activity and TBARS levels showed a significant decrease in the stress group compared to control. After administration of AC, the activity of Na- K- ATPase and levels of TBARS showed a tendency to revert back to normal. However there was no effect on AOPP levels, even after the treatment, which remained high. CONCLUSION The present study shows the preventive action of AC rhizome powder on stress induced cognitive functions and modulatory effect on antioxidants and Na-K-ATPase activity.

Role of Redox Metals, Oxidative Protein Products and Antioxidant Potentials of Thiols in Diabetic Retinopathy

Role of Redox Metals, Oxidative Protein Products and Antioxidant Potentials of Thiols in Diabetic Retinopathy Oxidative stress has been proved in the pathogenesis of diabetes mellitus (DM) and diabetic retinopathy (DR) not only by the reactive oxygen species (ROS) but also due to non-enzymatic protein glycosylation, auto-oxidation of glucose, impaired glutathione metabolism, alteration in the antioxidants and advanced oxidative protein product formation. The current study was undertaken to establish the relationship between iron, copper and antioxidants like reduced glutathione (GSH), total thiols, and advanced oxidation protein products (AOPP) as well as total protein and albumin. The study group consisted of a total of 90 subjects which included non-diabetic healthy controls (n=30), diabetes mellitus patients (n=30), and diabetic retinopathy patients (n=30). All the parameters were measured using spectrophotometric methods. AOPP levels showed a very highly significant increase in DR patients and in DM patients compared to normal controls, the AOPP levels being higher in the DR compared to the DM patients (p= 0.001). The levels of thiols showed a very highly significant decrease in DR and DM as compared to normal subjects. The total proteins level showed a very highly significant decrease (P = 0.001) in DR and DM compared to normal. There was no change in the level of albumin. A significant increase in the levels of iron was observed in DR when compared to DM and control. The levels of copper in DR showed a very highly significant increase when compared to DM and controls (p = 0.001). Our study indicates a possible increase in the copper and iron-mediated generation of ROS thereby leading to increased consumption of antioxidants in the body. Uloga Redoks Metala, Proizvoda Oksidacije Proteina i Antioksidantnih Potencijala Tiola u Dijabetesnoj Retinopatiji Prisustvo oksidativnog stresa u patogenezi dijabetesa (DM) i dijabetesne retinopatije (DR) dokazano je ne samo zahvaljujući prisustvu reaktivnih vrsta kiseonika (ROS) već i zbog neenzimske glikozilacije proteina, autooksidacije glukoze, poremećenog metabolizma glutationa, promena u stvaranju antioksidanata i naprednih proizvoda oksidacije proteina. Ova studija sprovedena je kako bi se ustanovio odnos između gvožđa, bakra i antioksidanata kao što je redukovani glutation (GSH), ukupnih tiola i naprednih proizvoda oksidacije proteina (AOPP) kao i ukupnih proteina i albumina. Ispitivanu grupu činilo je ukupno 90 subjekata, odnosno zdravih kontrola (n=30), pacijenata sa dijabetesom (n=30) i pacijenata sa dijabetesnom retinopatijom (n=30). Svi parametri izmereni su pomoću spektrofotometrijskih metoda. Uočen je veoma značajan porast nivoa AOPP kod pacijenata sa DR i DM u odnosu na zdrave kontrolne subjekte, s tim što su nivoi AOPP bili viši u DR nego u DM (p=0,001). U poređenju sa zdravim ispitanicima, nivoi tiola bili su veoma značajno sniženi u DR i DM. Nivo ukupnih proteina bio je veoma značajno snižen (p=0,001) u DR i DM u poređenju sa kontrolnom grupom, dok u nivou albumina nije bilo promena. Značajan porast nivoa gvožđa uočen je u DR u poređenju sa DM i kontrolnom grupom. Nivoi bakra u DR pokazali su veoma značajan porast u poređenju sa DM i kontrolnom grupom (p=0,001). Naša studija ukazuje na potencijalni porast produkcije ROS uz posredstvo bakra i gvožđa usled koje dolazi do povišene potrošnje antioksidanata u telu.

Effect of prenatal stress on expression of glutathione system in neonatal rat brain.

AIM Prenatal stress is known to adversely affect the fetal brain development and also neuronal loss. The mechanism(s) associated with prenatal stress induced developmental neurotoxicity remains obscure. Few studies point to the glutathione (GSH) antioxidant system which is an important molecular target for this toxicant. Hence the present study investigates the effect of prenatal stress on glutathione system in neonatal rat brain. MATERIAL AND METHODS Three to four months old pregnant Wistar rats were subjected to restraint stress during early or late gestational period. The offspring were sacrificed on 40th day and their brain homogenate was subjected to antioxidant studies. The serum corticosterone and adrenal ascorbic acid levels were also estimated from offspring. RESULTS The prenatal stress has resulted in an increase in the serum corticosterone and reduced adrenal ascorbic acid levels in neonatal pups. Prenatal stress during early or late gestation life showed reduced glutathione, glutathione reductase (GSSG-Rd) and superoxide dismutase (SOD) activity in offspring brain homogenate. CONCLUSION These data suggest that stress during early or late gestation period affect glutathione system in developing neonatal rat brain, which is associated with elevated serum corticosterone and reduced adrenal ascorbic acid levels.