Fresh Fruit Juice of Opuntia dillenii Haw. Attenuates Acetic Acid-Induced Ulcerative Colitis in Rats.

The present study aimed to evaluate the protective effect of fresh fruit juice of Opuntia dillenii Haw. (FJOD) on acetic acid-induced ulcerative colitis in rats. Fresh FJOD (2.5 and 5 ml/kg) and sulfasalazine (100 mg/kg) were given orally for seven consecutive days prior to colitis induction on the eighth day by intrarectal acetic acid (4% v/v) administration. Macroscopic, clinical activity scoring, biochemical, and histopathological examinations of colon were used to assess colonic damage. FJOD and sulfasalazine treatment significantly attenuated the macroscopic damage, clinical activity score, and wet weight of the colon when compared to disease control and further showed significantly reduced levels of myeloperoxidase, malondialdehyde, and serum lactate dehydrogenase and enhanced colonic levels of reduced glutathione. The protective effect of FJOD may be attributed to its antioxidant and anti-inflammatory activities in ulcerative colitis. The observed effects may be due to the presence of phenolics, flavonoids, and betalains in the fruit juice of Opuntia dillenii.

Polyphenolic enriched extract of Cassia glauca Lamk, improves streptozotocin-induced type-1 diabetes linked with partial insulin resistance in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditionally Cassia glauca (CG) has been used to treat diabetes. AIM OF THE STUDY: The study was undertaken to evaluate anti-diabetic and antioxidant activity of polyphenolic enriched extract of CG in standardized streptozotocin (STZ)-induced diabetic rats. MATERIALS AND METHODS: The effect of ethanol (CGE) and water (CGW) extracts of CG (200 and 400mg/kg) treatment were evaluated in STZ (50mg/kg, iv) induced diabetic rats. On 10th day, oral glucose tolerance test and degree of insulin resistance was calculated. On 13th day, insulin tolerance test was performed to know the peripheral utilization of glucose. On 15th day, blood glucose, lipid profiles and endogenous antioxidant levels were estimated. In addition, the effects on oral glucose/sucrose tolerance test in normal rats. Further, HPLC fingerprinting profile of CGE and simultaneous quantification of biomarkers were carried out. RESULTS: Supplementation with CGE and CGW significantly reduced STZ-induced deleterious effects and improved glucose tolerance, and insulin tolerance. In addition, supplementation also decreased oxidative stress by improving endogenous antioxidant levels. Furthermore, administration significantly improves sucrose tolerance suggesting that extract possess inhibition of α-glucosidase enzyme. Further, HPLC studies revealed that CGE contains three bioactive polyphenolic compounds viz., rutin (0.10±0.01mg/g), luteolin-7-glucoside (0.06±0.01mg/g) and isorhoifolin (0.7±0.05mg/g). CONCLUSION: Observed beneficial outcome of CG might be attributed to the presence of polyphenolic compounds and mediated by interacting with multiple targets of diabetes and oxidative stress. Taken together, this study provided the scientific evidence for the traditional use of CG.

Effect of Embelin Against Lipopolysaccharide-induced Sickness Behaviour in Mice.

Sickness behaviour is a coordinated set of adaptive behavioural changes that develop in ill individuals during the course of an infection. It is relevant to understanding depression and some aspects of the suffering that in cancer. Embelin has been reported to possess antiinflammatory, neuroprotective and anxiolytic assets and has been shown to inhibit nuclear factor κB pathway and cytokine production. The present study was undertaken to investigate the effect of embelin isolated from Embelia ribes Burm in lipopolysaccharide (LPS)-induced sickness behaviour in mice. Adult male Swiss albino mice were pre-treated with embelin (10 and 20 mg/kg, p.o.) or dexamethasone (1 mg/kg, i.p.) for 3 days and then challenged with LPS (400 µg/kg, i.p.). At different time intervals of post-LPS challenge, sickness behaviour was evaluated in the animals by battery of behavioural tests (plus maze, open field, light-dark box, forced swim, social behaviour assessment, sucrose preference and food and water intake). Levels of oxidative stress makers (reduced glutathione and lipid peroxidation) in mice brain were also analysed. LPS induced behavioural alterations, anhedonia and anorexia, in mice. Pre-treatment with embelin attenuated behavioural changes induced by LPS. In addition, embelin prevented anhedonia, anorexia and ameliorated brain oxidative stress markers. The experimental outcomes of the present study demonstrated protective effect of embelin in LPS-induced sickness behaviour in mice. Copyright © 2016 John Wiley & Sons, Ltd.

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.

Anti-diabetic and anti-cataract effects of Chromolaena odorata Linn., in streptozotocin-induced diabetic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Chromolaena odorata Linn., is used in traditional Indian medicine in the treatment of diabetes and eye problems. AIM OF THE STUDY: The present study was designed to investigate the effect of the ethanol extract Chromolaena odorata leaves (ACO) in streptozotocin (STZ; 45 mg/kg, i.v) induced diabetes and cataract in rats. MATERIALS AND METHODS: Different doses of ACO (200 and 400mg/kg) was administered once daily for eight weeks to STZ-induced diabetic rats. To know the mechanism of action of title plant, AUC(glucose), AUC(insulin), Homeostatic Model Assessment (HOMA), insulin tolerance test (ITT) and glucose uptake by rat hemi-diaphragms were carried out. Further, cataract score was taken once in a week upto eight weeks and opacity index was measured. HPLC fingerprinting profiling of ACO was also carried out. RESULTS: Administration of ACO exhibited significant reduction in glucose, HOMA, lipid profiles and significantly improved glucose and insulin tolerance, glycogen content, glucose uptake by skeletal muscle, serum insulin and HDL-c levels. In addition, ACO also decreased oxidative stress by improving endogenous antioxidants. Further, treatment of ACO showed significantly reduced onset and extent of cataract. CONCLUSION: The present data suggested that the treatment of ACO reversed the STZ-induced diabetes and cataract in rats. The observed beneficial effects may be mediated by interacting with multiple targets operating in diabetes mellitus and its complication. Taken together, this study provided the scientific evidence for the traditional use of Chromolaena odorata.

Evaluation of anxiolytic effect of Erythrina mysorensis Gamb. in mice.

AIM AND OBJECTIVES: To evaluate anxiolytic effect of stem bark ethanol and chloroform extracts of Erythrina mysorensis in mice. MATERIALS AND METHODS: The anxiolytic activity was examined by using the elevated plus maze (EPM) and open field test (OFT), and motor coordination by rotarod test (RRT). Twenty four Swiss albino male mice were divided into four groups of six mice each. Group 1 received vehicle (normal saline); group 2 received diazepam (1 mg/kg); groups 3 and 4 received ethanolic and chloroform extract of Erythrina mysorensis, 200 and 400 mg/kg p.o., respectively. RESULTS: Mice treated with diazepam (1 mg/kg, p.o.) showed significant (P < 0.001) increase ini the percentage of open arms entries and time spent whereas, in closed arm the number of entries and time spent were significantly (P < 0.05) decreased. Oral administration of chloroform and ethanol extract of E. mysorensis exhibited significant (P < 0.05) increase in the number of open arm entries and time spent with significant (P < 0.05) reduction in number of entries and time spent in the closed arm as compared to group 1. Chloroform and ethanol extracts treated mice also produced significant increase in the number of rearings (P < 0.05), assisted rearings and number of squares crossed (P < 0.01). Rotarod test showed significant (P < 0.01) reduction in motor activity at 45 min with diazepam and E. mysorensis extracts (400 mg/kg) as compared to groups 3 and 1. CONCLUSION: Erythrina mysorensis possess significant anxiolytic activity in the mice. It can be a promising anxiolytic agent.

Immunomodulatory and antioxidant effect of Leptadenia reticulata leaf extract in rodents: possible modulation of cell and humoral immune response.

CONTEXT: Leptadenia reticulata Linn. (Asclpiadaceae) commonly known as "dodi," is an Indian medicinal plant which is known to have ethno-medical uses such as stimulant, tonic, immunostimulant and is one of the ingredient in ayurvedic formulation called as "Chawanprash," which is widely used in India to increase the strength of immune system. OBJECTIVE: The aim of present study is to evaluate immunomodulatory and antioxidant activity of ethanolic extract of L. reticulata L. leaves in rodents. METHODS: Haemagglutinating antibody (HA) titre, haematological profile (Hb, WBC, RBC), lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), delayed type of hypersensitivity (DTH) response, neutrophil adhesion test and carbon clearance assay were determined by in vivo experiments. RESULTS: The evaluation of immunomodulatory potential of L. reticulata (100, 200 mg/kg, p.o.) evoked a significant dose-dependent increase in antibody titre values; DTH reaction induced by SRBC and potentiated percentage neutrophil adhesion to nylon fibers as well as phagocytosis in carbon clearance assay. Also it caused significant increase in haematological profile, GSH, SOD, CAT activity and significantly decreased LPO levels in cyclophosphamide-induced immunosuppressed rats. CONCLUSION: The results obtained in this study indicate that L. reticulata possesses potential immunomodulatory and antioxidant activity and can play a major role in reducing the risk to develop immunodeficiency disorders.

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.

Antidiabetic effect of Ficus racemosa Linn. stem bark in high-fat diet and low-dose streptozotocin-induced type 2 diabetic rats: a mechanistic study.

The present study was designed to investigate the effects of the ethanol extract of Ficus racemosa (FRE) on biochemical parameters in type 2-like diabetes, induced by a combination of standardised high-fat diet and low-dose streptozotocin (25mgkg(-1), i.p.) in rats. To elucidate the mode of action of FRE, its effects on a battery of targets involved in glucose homeostasis was evaluated. FRE (200 and 400mgkg(-1), p.o.), in a dose-dependent manner, altered the biochemical parameters and significantly improved glucose tolerance and HDL-c levels. In different bioassays, FRE showed inhibition of PTP-1B (IC50 12.1µg/mL) and DPP-IV (42.5%). FRE exhibited 82.6% binding to PPAR-γ. Furthermore FRE exhibited stimulation of glucose uptake by skeletal muscles (hemi-diaphragm). Bergenin was quantified in bioactive-FRE by high-performance liquid chromatography (0.15%w/w). This is the first report demonstrating the effectiveness of F. racemosa stem bark in type 2 diabetes and targets involved in it.

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.

Anxiolytic activity of Nymphaea alba Linn. in mice as experimental models of anxiety.

OBJECTIVE: The aim of the present work was to evaluate the anxiolytic effect of an ethanolic extract of Nymphaea alba Linn. in mice. MATERIALS AND METHODS: The elevated plus maze test (EPMT), light and dark test (L and DT) and open field test (OFT) were used to assess the anxiolytic activity of the ethanolic extract of N. alba Linn. in mice. In addition, aggressive behavior and motor coordination was also assessed by foot shock induced aggression test (FSIAT) and rota rod test (RRT). Diazepam 1 mg/kg served as a standard anxiolytic drug, administered orally. RESULTS: The ethanolic extract of N. alba (100 and 200 mg/kg, p.o.) significantly increased the percentage of time spent and number of entries in open arm in EPMT. In L and DT, the extract produced significant increase in time spent, number of crossing and decrease in the duration of immobility in light box. In OFT, the extract showed significant increase in number of rearings, assisted rearings and number of square crossed, all of which are demonstrations of exploratory behavior. In FSIAT, N. alba extract attenuated aggressive behavior related to anxiolytic activity, such as number of vocalization, leaps, rearing, biting/attacks and facing each other in paired mice. Furthermore, the extract produced skeletal muscle relaxant effect assessed by RRT. CONCLUSION: The results of the present study suggest that an ethanolic extract of N. alba may possess anxiolytic activity and provide a scientific evidence for its traditional claim.

Anticonvulsant activity of embelin isolated from Embelia ribes.

Anticonvulsant activity of embelin (2.5, 5 and 10mg/kg, i.p.) was studied. It showed a significant inhibition of the seizures induced by electroshock and pentylenetetrazole in a dose dependent manner and the activity was comparable to phenytoin and diazepam. Significant decrease in locomotion revealing its CNS depressant activity was observed. The findings suggest that embelin possess anticonvulsant activity against both grand mal and petit mal epilepsy.

Antidiabetic effect of Dodonaea viscosa aerial parts in high fat diet and low dose streptozotocin-induced type 2 diabetic rats: a mechanistic approach.

CONTEXT: High fat diet (HFD) and low-dose streptozotocin (STZ) is an ideal model for type 2 diabetes mellitus (T2DM) that would closely reflect the natural history and metabolic characteristics of human T2DM and is also suitable for pharmacological screening. OBJECTIVE: The present study was designed to investigate the effect of the water extract (DVW) and the polar fraction of ethanol extract (DVE-4) of Dodonaea viscosa (L). Jacq. (Sapindaceae) on biochemical parameters in type 2 diabetes induced by a standardized HFD and low dose streptozotocin (25 mg/kg) in rats. Further, to elucidate the mode of action we evaluated its effects on a battery of targets involved in glucose homeostasis (in vitro studies). MATERIALS AND METHODS: Different doses of DVW and DVE-4 were administered once daily for two weeks to HFD + STZ diabetic rats. Quantification of biomarker quercetin was done using HPLC. RESULTS AND DISCUSSION: Both DVW and DVE-4 dose-dependently reduced blood glucose, serum insulin, homeostatic model assessment (HOMA), lipid profiles, and significantly improved glucose tolerance and HDL-c levels. In addition, the extract and fraction also decreased oxidative stress by improving endogenous antioxidants. In different, bioassays, DVW and DVE-4 showed inhibition of PTP-1B and at a concentration of 10 µg/mL showed 60 and 54.2% binding to PPARγ, respectively. Both extract/fraction exhibited stimulation of glucose uptake by skeletal muscles. CONCLUSION: Taken together, these results suggest that DVW and DVE-4 inhibits HFD + STZ-induced insulin resistance, lipid abnormalities and oxidative stress indicating that these effects may be mediated by interacting with multiple targets operating in diabetes mellitus.

Hepatocurative potential of sesquiterpene lactones of Taraxacum officinale on carbon tetrachloride induced liver toxicity in mice.

The hepatocurative potential of ethanolic extract (ETO) and sesquiterpene lactones enriched fraction (SL) of Taraxacum officinale roots was evaluated against carbon tetrachloride (CCl 4 ) induced hepatotoxicity in mice. The diagnostic markers such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and total bilirubin contents were significantly elevated, whereas significant reduction in the level of reduced glutathione (GSH) and enhanced hepatic lipid peroxidation, liver weight and liver protein were observed in CCl 4 induced hepatotoxicity in mice. Post-treatment with ETO and SL significantly protected the hepatotoxicity as evident from the lower levels of hepatic enzyme markers, such as serum transaminase (ALT, AST), ALP and total bilirubin. Further, significant reduction in the liver weight and liver protein in drug-treated hepatotoxic mice and also reduced oxidative stress by increasing reduced glutathione content and decreasing lipid peroxidation level has been noticed. The histopathological evaluation of the liver also revealed that ETO and SL reduced the incidence of liver lesions induced by CCl 4 . The results indicate that sesquiterpene lactones have a protective effect against acute hepatotoxicity induced by the administration of CCl 4 in mice. Furthermore, observed activity of SL may be due to the synergistic action of two sesquiterpene lactones identified from enriched ethyl acetate fraction by HPLC method.

Adaptogenic and in vitro antioxidant activity of flavanoids and other fractions of Argyreia speciosa (Burm.f) Boj. in acute and chronic stress paradigms in rodents.

Argyreia speciosa (sweet) (Burm.f.) Boj. is an Ayurvedic rasayana plant used as an adaptogen. The present study reports the investigations done on the adaptogenic property of ethanol (EtAS; 100 and 200 mg/kg; po), ethyl acetate (EAAS; 100 and 200 mg/kg; po) fraction and flavanoids such as quercetin and kaempferol (25 mg/kg; po) of the root. Immobilization induced acute stress (AS; 3 days) and chronic stress (CS; 7 days) and swimming induced stress models were used to screen the anti-stress effect of the plant fractions and isolated flavanoids. The tested doses of EtAS and isolated flavanoids were able to produce significant effects in normalizing altered serum biochemical parameters and the severity of ulcer in both AS and CS models. Higher dose of EtAS, quercetin and kaempferol (25 mg/kg; po) were found to be significant in restoring the hypertrophy of adrenal gland and atrophy of spleen and thymus gland only in CS model. Greater swimming time was noted in the mice pretreated with tested doses of flavanoids and EtAS. In addition, levels of adrenal ascorbic acid and cortisol were restored compared to stress control group. EtAS exhibited significant scavenging effect of DPPH, hydroxyl radical and LPO. Thus, EtAS, quercetin and kaempferol are capable of increasing the capacity to tolerate non-specific stress in experimental animals, as evident from restoration of large number of parameters in the stress models studied. Bioactivity of EtAS may be due to the synergetic action of isolated flavanoids. Improvement in stress markers may be due its prolong effect of resistance to stress and partly due to free radical scavenging activity.

Antidiabetic effect of Dodonaea viscosa (L). Lacq. aerial parts in high fructose-fed insulin resistant rats: a mechanism based study.

To study the effect and mode of action of water extract (DVW) and polar fraction of ethanol extract (DVE-4) of D. viscosa in high-fructose diet induced insulin resistance in male Wistar rats. D. viscosa's effects were evaluated on a battery of targets involved in glucose homeostasis (in vitro studies). Rats were rendered insulin resistant by feeding 66% (w/w) fructose and 1.1% (v/w) coconut oil mixed with normal pellet diet (NPD) for six weeks. DVW and DVE4 at different doses were administered simultaneously. At the end of the study, blood glucose, oral glucose tolerance test, lipid profile and insulin were estimated and homeostatic model assessment (HOMA) levels were calculated. In addition, enzymatic and nonenzymatic liver antioxidant levels were also estimated. Quantification of biomarker quercetin was done using HPLC. Fructose diet with DVW, DVE-4 significantly reduced blood glucose, serum insulin, HOMA, lipid profiles and significantly improved glucose tolerance and HDL-c levels. In addition, these extract and fraction also decreased oxidative stress by improving endogenous antioxidants. In different bioassays, DVW and DVE-4 inhibited protein tyrosine phosphatase-1B with IC50 65.8 and 54.9 microg/ml respectively and showed partial inhibition of dipeptidyl peptidase-IV. Moreover, DVW and DVE-4, at 10 microg/ml showed 60 and 54.2% binding to peroxisome proliferator-activated receptor-gamma. Further, 2.1% (w/w) of quercetin was quantified in bioactive-DVE-4 using HPLC method. The results provide pharmacological evidence of D. viscosa in treatment of prediabetic conditions and these effects may be mediated by interacting with multiple targets operating in diabetes mellitus.

Ficus racemosa Stem Bark Extract: A Potent Antioxidant and a Probable Natural Radioprotector.

Ethanol extract (FRE) and water extract (FRW) of Ficus racemosa (family: Moraceae) were subjected to free radical scavenging both by steady state and time resolved methods such as nanosecond pulse radiolysis and stopped-flow spectrophotometric analyses. FRE exhibited significantly higher steady state antioxidant activity than FRW. FRE exhibited concentration dependent DPPH, ABTS(*-), hydroxyl radical and superoxide radical scavenging and inhibition of lipid peroxidation with IC(50) comparable with tested standard compounds. In vitro radioprotective potential of FRE was studied using micronucleus assay in irradiated Chinese hamster lung fibroblast cells (V79). Pretreatment with different doses of FRE 1h prior to 2 Gy gamma-radiation resulted in a significant (P < 0.001) decrease in the percentage of micronucleated binuclear V79 cells. Maximum radioprotection was observed at 20 mug/ml of FRE. The radioprotection was found to be significant (P < 0.01) when cells were treated with optimum dose of FRE (20 mug/ml) 1 h prior to 0.5, 1, 2, 3 and 4 Gy gamma-irradiation compared to the respective radiation controls. The cytokinesis-block proliferative index indicated that FRE does not alter radiation induced cell cycle delay. Based on all these results we conclude that the ethanol extract of F. racemosa acts as a potent antioxidant and a probable radioprotector.

Antioxidant and radioprotective effect of the active fraction of Pilea microphylla (L.) ethanolic extract.

The ethanolic extract of Pilea microphylla (L.) was defatted, successively fractionated with acetone and the residue so obtained was found to be most potent when subjected to detailed free radical scavenging and in vivo radioprotection studies. The most active fraction reacts with free radicals, such as DPPH (50 microM), ABTS(.)(-) (100 microM) and (.)OH (generated by Fenton reaction) with IC(50) value of 23.15 microg/ml, 3.0 microg/ml and 310 microg/ml, respectively. The most active fraction inhibited iron-induced lipid peroxidation in phosphatidyl choline liposomes with an IC(50) of 13.74 microg/ml. The kinetics of scavenging of DPPH and ABTS(.)(-) radicals were followed at different concentrations of the fraction by employing stopped-flow studies. The observed first order decay rate constants at 200 microg/ml and 50 microg/ml of fraction with DPPH (50 microM) and ABTS(.)(-) (50 microM) were found to be 0.4s(-1) and 2.1s(-1), respectively. The fraction when screened for in vivo radioprotection in Swiss albino mice showed 80% protection at a dose of 900 mg/kg and with a DRF of about 1.12. The fraction was also found to protect livers of irradiated mice from depletion of endogenous antioxidant enzymes like glutathione, GST, SOD, catalase and thiols. The fraction also protected the villi height, increased the number of crypt cells while offering general protection to the intestine from acute radiation effects. The fraction also protected the hematopoietic system as assessed by endogenous spleen colony assay, contributing to the overall radioprotective ability.