Neuroprotective potential of Beta vulgaris L. in Parkinson's disease.

OBJECTIVE: The objective was to investigate the neuroprotective role of Beta vulgaris in Parkinson's disease (PD). MATERIALS AND METHODS: PD was induced by administration of reserpine (5 mg/kg/day, i.p for 5 consecutive days), haloperidol (1 mg/kg, i.p.), and tacrine (2.5 mg/kg, i.p.) in experimental animals. The symptoms of PD such as tremors, akinesia, rigidity, catalepsy, and vacuous chewing movements (VCMs) were evaluated. Foot shock-induced aggression (FSIA) model was used to confirm anti-parkinsonian activity. The methanolic extract of Beta vulgaris (MEBV) was administered at doses of 100, 200, and 300 mg/kg, p.o. The combination of L-dopa and carbidopa was used as a standard drug. Behavioral studies such as locomotor activity and grip strength were determined, and oxidative stress was evaluated in FSIA model in rat brain. RESULTS: Pretreatment with MEBV (200 and 300 mg/kg) significantly reduced the intensity of muscular rigidity, duration of catalepsy, akinesia, the number of tremors, VCMs, and increase fighting behavior. The locomotor activity and grip strength were significantly increased by MEBV. In FSIA, the biochemical analysis of brain revealed the increased level of lipid peroxidation (LPO) and decreased levels of superoxide dismutase (SOD) and catalase (CAT). MEBV significantly reduced LPO level and restored the defensive antioxidant enzymes SOD and CAT in rat brain. CONCLUSIONS: The results indicated the protective role of B. vulgaris against PD. The mechanism of protection may be due to augmentation of cellular antioxidants.

Protective effect of sitagliptin and rosuvastatin combination on vascular endothelial dysfunction in type-2 diabetes.

The present investigation aimed to evaluate the protective effects of sitagliptin, glimepiride, rosuvastatin and their combinations on oxidative stress and endothelial dysfunction in the aortic tissues in fructose-fed type-2 diabetic rats. Sitagliptin (20 mg/kg, p.o.), glimepiride (2 mg/kg, p.o.), rosuvastatin (5 mg/kg, p.o.) and their combinations were administered for 6 w after induction of diabetes by fructose (66%, w/v solution, p.o. for 8 w) in wistar rats. The effects were examined on body weight, serum glucose, triglyceride, cholesterol, blood pressure, heart rate, nitric oxide and antioxidant defensive enzymes. After completion of treatment schedule, the blood pressure was determined by invasive method and vascular reactivity was tested with adrenaline, noradrenaline and phenylephrine. Endothelial dysfunction was determined by acetylcholine and sodium nitroprusside-induced vasorelaxation studies on isolated rat aortas. Long term treatments significantly decreased body weight gain, serum glucose, triglyceride and cholesterol levels; normalize the heart rate, and blood pressure in fructose fed rats. The treatments significantly improved vascular reactivity to catecholamines with reduction in elevated blood pressure in type-2 diabetic rats. The significant improvement in the relaxant response to acetylcholine and sodium nitroprusside was obtained on isolated aortas. All the treatments were effective in restoring defensive antioxidant enzymes. Sitagliptin and rosuvastatin were able to reverse endothelial dysfunction in type-2 diabetes, but better ameliorating potential was found when used in combination.

Effect of bromocriptine on cardiovascular complications associated with metabolic syndrome in fructose fed rats.

OBJECTIVE: The objective of the present study was to evaluate the effect of bromocriptine on cardiovascular complications associated with type-2 diabetes mellitus (DM). MATERIALS AND METHODS: Metabolic syndrome or type 2 DM was induced by administration of fructose (66% solution, p.o.) in rats. Bromocriptine mesylate (10 mg/kg, i.p.) was given in fructose-treated rats for a period of 6 weeks after induction of diabetes. After drug treatment, the parameters such as body weight, food and water intake, serum glucose, triglycerides, cholesterol, insulin, and blood pressure (BP) were measured weekly and at the end of study. At the end of treatment, BP was determined by invasive method and vascular reactivity was tested with adrenaline (Adr), noradrenaline (NA), and phenylephrine (PE). Acetylcholine-induced vasorelaxation was tested on isolated rat aorta and histopathology of hearts was also done. RESULTS: Fructose-fed rats showed significant weight gain, hyperglycemia, hyperlipidemia, hyperinsulinemia, and rise of BP. Administration of bromocriptine at a dose 10 mg/kg, i.p. significantly decreased weight gain, serum glucose, triglyceride, cholesterol and insulin levels in rats fed on fructose. Bromocriptine also significantly reduced elevated BP in fructose-fed hypertensive rats. Chronic treatment with bromocriptine significantly improved the relaxant response to acetylcholine on fructose-fed hyperinsulinemic rat aorta and also reduced the pressor response to Adr, NA, and PE. Bromocriptine also showed a protection from hypertrophy and degenerative changes in myocardium. CONCLUSION: Bromocriptine has beneficial effect in reduction of cardiovascular complications associated with metabolic syndrome.

Cognitive enhancing and antioxidant activity of ethyl acetate soluble fraction of the methanol extract of Hibiscus rosa sinensis in scopolamine-induced amnesia.

OBJECTIVE: The objective of the present study was to evaluate the cognitive enhancing and antioxidant activity of Hibiscus rosa sinensis. MATERIALS AND METHODS: The learning and memory was impaired by administration of scopolamine (1 mg/kg, i.p.) in mice which is associated with altered brain oxidative status. The object recognition test (ORT) and passive avoidance test (PAT) were used to assess cognitive enhancing activity. Animals were treated with an ethyl acetate soluble fraction of the methanol extract of H. sinensis (25, 50 and 100 mg/kg, p.o). RESULTS: The ethyl acetate soluble fraction of the methanol extract of H. sinensis (EASF) attenuated amnesia induced by scopolamine and aging. The discrimination index (DI) was significantly decreased in the aged and scopolamine group in ORT. Pretreatment with EASF significantly increased the DI. In PAT, scopolamine-treated mice exhibited significantly shorter step-down latencies (SDL). EASF treatment showed a significant increase in SDL in young, aged as well as in scopolamine-treated animals. The biochemical analysis of brain revealed that scopolamine treatment increased lipid peroxidation and decreased levels of superoxide dismutase (SOD) and glutathione reductase (GSH). Administration of extract significantly reduced LPO and reversed the decrease in brain SOD and GSH levels. The administration of H. sinensis improved memory in amnesic mice and prevented the oxidative stress associated with scopolamine. The mechanism of such protection of H. sinensis may be due to augmentation of cellular antioxidants. CONCLUSION: The results of the present study suggested that H. sinensis had a protective role against age and scopolamine-induced amnesia, indicating its utility in management of cognitive disorders.

Anti-stress effect of ethyl acetate soluble fraction of Morus alba in chronic restraint stress.

CONTEXT: Restraint stress is a well-known method to induce chronic stress which leads to alterations in various behavioral and biochemical parameters. OBJECTIVE: The present work was designed to study anti-stress effects of Morus alba in chronic restraint stress (RS)-induced perturbations in behavioral, biochemical and brain oxidative stress status. MATERIALS AND METHODS: The stress was produced by restraining the animals inside an adjustable cylindrical plastic tube for 3 h once daily for ten consecutive days. The ethyl acetate soluble fraction of Morus alba (EASF) 25, 50, 100 mg/kg and diazepam (1 mg/kg) per day was administered 60 min prior to the stress procedure. The behavioral and biochemical parameters such as open field, cognitive dysfunction; leucocytes count; blood glucose and corticosteroid levels were determined. On day 10, the rats were sacrificed and biochemical assessment of superoxide dismutase (SOD), lipid peroxidation (LPO), catalase (CAT), and glutathione reductase (GSH) in whole rat brain were performed. RESULTS: Chronic restraint stress produced cognitive dysfunction, altered behavioral parameters, increased leucocytes count, SOD, LPO, glucose and corticosterone levels, with concomitant decrease in CAT and GSH activities. Gastric ulceration, adrenal gland and spleen weights were also used as the stress indices. All these RS induced perturbations were attenuated by EASF of Morus alba. DISCUSSION: The results of the study suggest that in addition to its classically established pharmacological activities, the plant also has immense potential as an anti-stress agent of great therapeutic relevance. CONCLUSION: This study indicates the beneficial role of Morus alba for the treatment of oxidative stress-induced disorders.

Neuroprotective effect of Hibiscus rosa sinensis in an oxidative stress model of cerebral post-ischemic reperfusion injury in rats.

CONTEXT: The ischemic brain lesions induced in rats by temporary occlusion of the bilateral common carotid arteries and restoration of blood flow to an ischemic brain region is associated with generation of reactive oxygen species with consequent reperfusion injury. OBJECTIVE: The present study investigated the neuroprotective potential of Hibiscus rosa sinensis L. (Malvaceae) in a bilateral common carotid artery (BCCA) occlusion model of global cerebral ischemic reperfusion. MATERIALS AND METHODS: The animals underwent 30 min BCCA occlusion and 45 min reperfusion. The methanol extract of H. sinensis (100, 200, 300 mg/kg/day for 6 days, p.o.) was administered 30 min before induction of BCCA occlusion. RESULTS: The bilateral common carotid artery occlusion resulted in increase in lipid peroxidation, and reduction in superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GSH) activity. The extract attenuated the ischemic reperfusion-induced increase in lipid peroxidation and fall in SOD, CAT, and GSH levels. The cerebral hypoperfusion caused a propensity towards anxiety and was accompanied by deficits of learning and memory. The extract ameliorated anxiety and there was improvement of learning and memory. DISCUSSION: The administration of H. sinensis prevented the oxidative stress and the biochemical changes associated with cerebral ischemic reperfusion injury. The mechanism of such protection of H. sinensis may be due to cerebral adaptation, through augmentation of cellular antioxidants such as GSH, SOD and CAT. The results suggest the protective role of H. sinensis in ischemic reperfusion injury. CONCLUSION: This study indicates the beneficial role of H. sinensis in cerebrovascular insufficiency states and dementia.

Adaptogenic effect of Morus alba on chronic footshock-induced stress in rats.

OBJECTIVE: The objective of the present study was to evaluate the adaptogenic property of the ethyl acetate-soluble fraction of methanol extract of Morus alba roots against a rat model of chronic stress (CS). MATERIALS AND METHODS: Rats were exposed to stress procedure for 21 days. The stress procedure was mild, unpredictable footshock, administered for 1 h once daily for 21 days. Rats were administered with the ethyl acetate soluble fraction of methanol extract of M. alba roots (25, 50 and 100 mg/kg p.o) 1 h before footshock for 21 days and behavioral parameters were evaluated for cognitive dysfunction and depression using elevated plus maze and despair swim test, respectively. On day 21, rats were sacrificed immediately after stress and blood was collected for biochemical estimation. The adrenal gland and spleen were dissected for organ weight and the stomach was dissected for ulcer score. RESULTS: CS significantly induced cognitive deficit, mental depression and hyperglycemia and increased blood corticosterone levels, gastric ulcerations and adrenal gland weight, but decreased the splenic weight. Pre-treatments with the ethyl acetate soluble fraction of methanol extract of M. alba roots (25, 50 and 100 mg/kg, p.o.) significantly attenuated the CS-induced perturbations. Diazepam (1 mg/kg, p.o.) was used as the standard antistress drug. CONCLUSION: The results indicate that M. alba possesses significant adaptogenic activity, indicating its possible clinical utility as an antistress agent.

Anti-dopaminergic effect of the methanolic extract of Morus alba L. leaves.

OBJECTIVE: To evaluate the effect of methanolic extract of Morus alba L. leaves on dopaminergic function. MATERIALS AND METHODS: The effect of the methanolic extract of Morus alba L. leaves was evaluated on haloperidol and metoclopramide induced catalepsy, foot shock-induced aggression, amphetamine-induced stereotyped behavior and phenobarbitone induced sleeping in mice. In each of these tests, the extract was administered in doses of 50, 100 and 200 mg/kg, i.p., 30 min before performing the test in mice. Further, the inhibitory effect of the extract on dopamine was studied using isolated rat vas deferens. RESULTS: The extract produced significant dose dependent potentiation of haloperidol (1 mg/kg, i.p.) and metoclopramide (20 mg/kg, i.p.) induced catalepsy in mice. The extract significantly reduced number of fights and increased latency to fights in foot shock-induced aggression; it also decreased amphetamine (1 mg/kg, i.p.) induced stereotyped behavior in a dose dependent manner. The sleeping time induced by phenobarbitone (50 mg/kg, i.p.) too was prolonged. The extract inhibited contractions produced by dopamine on isolated rat vas deferens. CONCLUSION: The results suggest that the methanolic extract of Morus alba L. possesses antidopaminergic activity. Further neurochemical investigation can explore the mechanism of action of the plant drug with respect to antidopaminergic functions and help to establish the plant as an antipsychotic agent.