Protective effect of Calendula officinalis Linn. flowers against 3-nitropropionic acid induced experimental Huntington's disease in rats.

Oxidative stress (OS) and nitric oxide mechanisms have been recently proposed in 3-nitropropionic acid (3-NP)-induced neurotoxicity. The compounds, having antioxidant, anti-inflammatory and estrogenic effects, have been suggested for neuroprotection in different experimental models. Calendula officinalis Linn. flower extract (COE) is known for its potent antioxidant, anti-inflammatory, estrogenic and neuroprotective activities. Hence, the present study was designed to evaluate the neuroprotective effect of COE on 3-NP-induced neurotoxicity in rats by observing behavioral changes, OS and striatal damage in rat brain. Adult female Wistar rats were pretreated with vehicle or COE (100 and 200 mg/kg) for 7 days, followed by cotreatment with 3-NP (15 mg/kg, intraperitoneally) for the next 7 days. At the end of the treatment schedule, rats were evaluated for alterations in sensory motor functions and short-term memory. Animals were sacrificed and brain homogenates were used for the estimation of lipid peroxidation (LPO), glutathione, total thiols, glutathione S-transferase, catalase and nitrite. A set of brain slices was used for the evaluation of neuronal damage in the striatal region of the brain. 3-NP caused significant alterations in animal behavior, oxidative defense system evidenced by raised levels of LPO and nitrite concentration, and depletion of antioxidant levels. It also produced a loss of neuronal cells in the striatal region. Treatment with COE significantly attenuated behavioral alterations, oxidative damage and striatal neuronal loss in 3-NP-treated animals. The present study shows that COE is protective against 3-NP-induced neurotoxicity in rats. The antioxidant, anti-inflammatory and estrogenic properties of COE may be responsible for its neuroprotective action.

Protective Effect of Calendula officinalis L. Flowers Against Monosodium Glutamate Induced Oxidative Stress and Excitotoxic Brain Damage in Rats.

Monosodium glutamate (MSG) is a popular flavour enhancer used in food industries; however, excess MSG is neurotoxic. Oxidative stress is well documented in MSG induced neurotoxicity. The compounds having antioxidant and anti-inflammatory properties reportedly possess beneficial effects against various neurotoxic insults. Calendula officinalis Linn. flower extract (COE) is known for its potent antioxidant and anti-inflammatory activities. Hence, this present study has been designed to evaluate the neuroprotective effect of COE on MSG-induced neurotoxicity in rats. Adult Wistar rats were administered systemically for 7 days with MSG and after one h of MSG injection, rats were treated with COE (100 and 200 mg/kg) orally. At the end the treatment period, animals were assessed for locomotor activity and were sacrificed; brains were isolated for estimation of LPO, GSH, CAT, TT, GST, Nitrite and histopathological studies. MSG caused a significant alteration in animal behavior, oxidative defense (raised levels of LPO, nitrite concentration, depletion of antioxidant levels) and hippocampal neuronal histology. Treatment with COE significantly attenuated behavioral alterations, oxidative stress, and hippocampal damage in MSG-treated animals. Hence, this study demonstrates that COE protects against MSG-induced neurotoxicity in rats. The antioxidant and anti-inflammatory properties of COE may be responsible for its observed neuroprotective action.

Protective effect of hydroalcoholic extract of Mimusops elengi Linn. flowers against middle cerebral artery occlusion induced brain injury in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: In the traditional Indian and Thai system of medicine, Mimusops elengi Linn., flower is used as brain tonic and to calm anxiety and panic attacks. AIM OF THE STUDY: The present study was designed to investigate the neuroprotective effect of hydroalcoholic extract of Mimusops elengi (ME) against cerebral ischemic reperfusion injury in rats. MATERIALS AND METHODS: Male rats were pretreated with ME (100 and 200mg/kg) for seven days and focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) method. After 60min of MCAO and 24h of reperfusion, a battery of behavioral tests assessed the extent of neurological deficits. Infarct volume and brain edema were measured in TTC stained brain sections and the extent of blood brain barrier (BBB) disruption was observed by Evan's blue extravasation. Oxidative and nitrative stress parameters were estimated in the brain homogenates. Further, simultaneous quantification of five polyphenolic biomarkers were done using HPLC. RESULTS: Pretreatment with ME at doses of 100 and 200mg/kg significantly improved the neurobehavioral alterations and reduced the infarct volume, edema and extent of BBB disruption induced by ischemia reperfusion injury. It also prevented the alteration in the antioxidant status and reduced the nitrite levels when compared to ischemic animals. Further, HPLC studies revealed that ME contains five bioactive polyphenolic compounds. CONCLUSIONS: These results clearly indicate the neuroprotective effect of ME against stroke like injury. The observed protective effect might be attributed to the polyphenolic compounds and their antioxidant and anti-inflammatory property.

Restoration of brain antioxidant status by hydroalcoholic extract of Mimusops elengi flowers in rats treated with monosodium glutamate.

Monosodium glutamate (MSG) is commonly used as a flavor enhancer in many countries. However, overconsumption of MSG has been reported to produce detrimental effects on several organs. It mainly affects the normal physiology and function of the brain and causes severe oxidative stress. Mimusops elengi Linn. traditionally is used in many countries as a brain tonic and to calm anxiety and panic attacks. The effect of standardized hydroalcoholic extract of M. elengi flowers (ME) was evaluated against MSG-induced oxidative stress and excitotoxicity in Wistar rats. Excitotoxicity was induced by intraperitoneal administration of MSG (2 g/kg) for 7 days, and ME (100 and 200 mg/kg) was administered for 3 days before and for 7 days with administration of MSG. Animals were evaluated for locomotor activity, and brain homogenates were estimated for the levels of antioxidants and nitrite. In animals treated with MSG, pretreatment with ME improved ambulatory behavior, reduced lipid peroxidation and nitrite levels, and restored the enzymatic and nonenzymatic antioxidant (glutathione, total thiols, glutathione-S-transferase and catalase) status to near-normal levels; these were altered in the MSG control animals. Altogether, this investigation demonstrates the neuroprotective effect of ME against excitotoxicity and oxidative stress induced by MSG, and the observed protective effect might be attributed to the potential antioxidant property of ME.

Protective effect of embelin from Embelia ribes Burm. against transient global ischemia-induced brain damage in rats.

Embelia ribes is being used in Indian traditional herbal medicine for the treatment of mental disorders and as brain tonic. The present study was designed to investigate the protective effects of embelin from E. ribes on global ischemia/reperfusion-induced brain injury in rats. Transient global ischemia was induced by occluding bilateral common carotid arteries for 30 min followed by 24-h reperfusion. Neurological functions were measured using sensorimotor tests. Ischemia/reperfusion-induced neuronal injury was assessed by cerebral infarct area, biochemical and histopathological examination. Pretreatment of embelin (25 and 50 mg/kg, p.o.) significantly increased locomotor activity and hanging latency time and decreased beam walking latency when compared with ischemic control. The treatment also reduced significantly the lipid peroxidation and increased the total thiol content and glutathione-S-transferase activity in brain homogenates. The decreased cerebral infarction area in embelin-treated groups and histopathological observations confirmed the above findings. These observations suggested that embelin is a neuroprotective agent and may prove to be useful adjunct in the treatment of stroke.