Anti-diabetic activity of green tea polyphenols and their role in reducing oxidative stress in experimental diabetes

An aqueous solution of green tea polyphenols (GTP) was found to inhibit lipid peroxidation (LP), scavenge hydroxyl and superoxide radicals in vitro. Concentration needed for 50% inhibition of superoxide, hydroxyl and LP radicals were 10, 52.5 and 136 micro g/ml, respectively. Administration of GTP (500 mg/kg b.wt.) to normal rats increased glucose tolerance significantly (P<0.005) at 60 min. GTP was also found to reduce serum glucose level in alloxan diabetic rats significantly at a dose level of 100 mg/kg b.wt. Continued daily administration (15 days) of the extract 50, 100 mg/kg b.wt. produced 29 and 44% reduction in the elevated serum glucose level produced by alloxan administration. Elevated hepatic and renal enzymes produced by alloxan were found to be reduced (P<0.001) by GTP. The serum LP levels which was increased by alloxan and was reduced by significantly (P<0.001) by the administration of 100 mg/kg b.wt. of GTP. Decreased liver glycogen, after alloxan administration showed a significant (P<0.001) increase after GTP treatment. GTP treated group showed increased antioxidant potential as seen from improvements in superoxide dismutase and glutathione levels. However catalase, LP and glutathione peroxidase levels were unchanged. These results indicate that alterations in the glucose utilizing system and oxidation status in rats increased by alloxan were partially reversed by the administration of the glutamate pyruvate transaminase.     

Tumour reducing and anticarcinogenic activity of Acanthus ilicifolius in mice.

Alcoholic extract of Acanthus ilicifolius (250,500 mg/kg b wt) was found to be effective against tumour progression and carcinogen induced skin papilloma formation in mice. The extract was found to be cytotoxic towards lung fibroblast (L-929) cells in 72 h MTT assay and the concentration required for 50% cell death was 18 microg/ml. Oral administration of the extract (500 mg/kg b wt) reduced the tumour volume and administration of the same concentration increased the life span by 75% in ascites tumour (EAC cells) harbouring animals. The extract also significantly delayed the onset of dimethylbenzanthrazene DMBA/Croton oil induced skin papilloma in mice in a dose dependent manner.     

Antitumour and anticarcinogenic activity of Phyllanthus amarus extract

Aqueous extract of Phyllanthus amarus (P. amarus) treatment exhibited potent anticarcinogenic activity against 20-methylcholanthrene (20-MC) induced sarcoma development and increased the survival of tumour harboring mice. The extract administration (p.o) was also found to prolong the life span of Dalton's Lymphoma Ascites (DLA) and Ehrlich Ascites Carcinoma (EAC) bearing mice and reduced the volume of transplanted solid tumours. The extract inhibited aniline hydroxylase, a P-450 enzyme. The concentration required for 50% inhibition (IC(50)) was found to be 540 microg/ml. The extract was found to inhibit DNA topoisomerase II of Saccharomyces cerevisiae mutant cell cultures and inhibited cell cycle regulatory enzyme cdc25 tyrosine phosphatase (IC(50-25) microg/ml). Antitumour and anticancer activity of P. amarus may be related with the inhibition of metabolic activation of carcinogen as well as the inhibition of cell cycle regulators and DNA repair.     

In vitro antioxidant and antithrombotic activity of Hemidesmus indicus (L) R.Br

The methanolic extract of Hemidesmus indicus (L) R.Br. (Asclepiadaceae) roots was found to inhibit lipid peroxidation and scavenge hydroxyl and superoxide radicals in vitro. The amount required for 50% inhibition of lipid peroxide formation was 217.5 micro g/ml. The concentrations needed to scavenge hydroxyl and superoxide radicals were 73.5 and 287.5 micro g/ml, respectively. The intravenous administration of this extract (5mg/kg body weight) in rabbits delayed the plasma recalcification time and enhanced the release of lipoprotein lipase enzyme significantly. The extract also inhibited ADP-induced platelet aggregation in vitro (50-250 micro g), which was comparable to commercial heparin.     

Gastroprotective effect of swallow root (Decalepis hamiltonii) extract: possible involvement of H(+)-K(+)-ATPase inhibition and antioxidative mechanism

The present study reports the antiulcer potentials of aqueous extract of swallow root (Decalepis hamiltonii Wight & Arn, SRAE) belonging to the family Asclepiadaceae. Swim stress-induced ulcers with an ulcer index (UI) of 6.0+/-0.01 was protected up to 43% and 72% at 100 and 200mg/kg b.w. of SRAE, respectively, similar to protection offered by ranitidine (79%) at 30mg/kg b.w. Depletion in antioxidant enzymes and increased Thiobarbituric Acid Reactive Substances (TBARS) were observed in ulcer-induced rats while SRAE fed rats showed normal levels. SRAE also normalized approximately 3.1 and 2.4 folds of increased H(+)-K(+)-ATPase and gastric mucin, respectively, in ulcerous animals, similar to the levels found in healthy controls. SRAE also possessed reducing power, free radical scavenging ability with an IC(50) of 0.17microg/mL gallic acid equivalent (GAE), comparable to that of BHA (IC(50)-0.08microg/mL). DNA protection up to 80% at 0.2microg was also observed. Toxicity studies indicated no lethal effects in rats fed up to 5g/kg b.w. Antioxidant, proton pump inhibition as well as boosting of gastric mucin effects of SRAE have been implicated to be responsible for antiulcer property of SRAE.     

Treatment of mice with a herbal preparation (mentat) protects against radiation-induced mortality

The effect of various doses (0, 5, 10, 20, 40, 80, 100, 120 and 160 mg/kg b. wt.) of 50% ethanolic extract of mentat (a herbal preparation) was studied on the survival of mice exposed to 10 Gy of gamma-radiation. Treatment of mice with different doses of mentat consecutively for fi ve days before irradiation delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls. Most of the doses of mentat provided protection against the gastrointestinal (GI) death, however, the highest protection against GI death was observed for 80 mg/kg mentat. This was also true for bone marrow deaths, where the highest number of survivors were observed at 30 days post-irradiation in this group (i.e. 80 mg/kg) when compared with the other doses of mentat. The evaluation of acute toxicity showed that mentat was non-toxic up to a dose of 1.5 g/kg b. wt., where no drug-induced mortality was observed. The LD50 dose of mentat was found to be 1.75 g/kg b. wt. Our study demonstrates that mentat can provide good radioprotection at a dose of 80 mg/kg, which is far below its toxic dose.     

Mitigation of thyroxine-induced hyperglycaemia by two plant extracts

Extracts of Trigonella foenum-graecum (TFG) seed and Allium sativum (AS) bulb were evaluated for their efficacy to ameliorate l-thyroxine (l-T4) induced hyperglycaemia in rats. Simultaneously, the serum cholesterol concentration, a supporting parameter for thyroid function, was also estimated. Thyroxine treatment in rats (300 microg/kg b. wt./day) increased the levels of both the thyroid hormones, namely thyroxine (T4) and tri-iodothyronine (T3) with a concomitant elevation in serum glucose concentration and a reduction in serum cholesterol level. Administration of TFG (220 mg/kg/day) and AS (500 mg/kg/day) extracts in hyperthyroid animals decreased the serum glucose concentration as well as the serum thyroid hormones. For comparison, propyl thiouracil (PTU), an antithyroid compound, was used as the standard at a daily dose of 10 mg/kg. The reductions in serum glucose and thyroid hormone concentrations in the plant extract treated groups were comparable to that in PTU treated animals. Our findings indicate that TFG seed and AS bulb extracts may prove to be effective in the treatment of thyroxine-induced hyperglycaemia.     

Evaluation of antioxidant activity of Cassia siamea flowers

The study was aimed at evaluating the antioxidant activity of alcoholic extract of Cassia siamea Lam. (Fabaceae) flowers. The extract was found to contain a large amount of polyphenols and also exhibited an immense reducing ability. At a concentration of 250 microg/ml, 96% of DPPH radicals and at 500 microg/ml, 42.7, 32.7 and 64.5% of O2-, H2O2 and NO respectively could be scavenged by C. siamea flower extract. The extract also inhibited OH radical induced oxidation of protein (BSA) and LPO in murine hepatic microsomes. The determination of metal chelating capacity of the extract indicated chelating of metal ions (Fe2+) to be a putative mechanism implicated in the inhibition of OH radical-induced BSA oxidation and LPO. C. siamea flower extract also exhibited a significant antioxidant activity in acute oxidative tissue injury animal model constituted by CCl4 induced hepatotoxicity. Oral administration of the extract at a dose of 50-150 mg/kg of body weight significantly protected from CCl4 induced elevation in AST and ALT in the serum, elevation in hepatic LPO, depletion of hepatic GSH and decrease in the activities of hepatic antioxidant enzymes: SOD, CAT and GPX. The extract also protected against histopathological changes produced by CCl4 such as necrosis, fatty changes, ballooning degeneration, etc. The data obtained in the present study suggests that the alcoholic extract of C. siamea flowers have potent antioxidant activity against free radicals, prevent oxidative damage to major biomolecules and afford significant protection against oxidative damage in the liver.     

Anti-diabetic activity of medicinal plants and its relationship with their antioxidant property

Methanolic extract (75%) of Terminalia chebula, Terminalia belerica, Emblica officinalis and their combination named 'Triphala' (equal proportion of above three plant extracts) are being used extensively in Indian system of medicine. They were found to inhibit lipid peroxide formation and to scavenge hydroxyl and superoxide radicals in vitro. The concentration of plant extracts that inhibited 50% of lipid peroxidation induced with Fe(2+)/ascorbate were food to be 85.5, 27, 74 and 69 micro g/ml, respectively. The concentration needed for the inhibition of hydoxyl radical scavenging were 165, 71, 155.5 and 151 micro g/ml, and that for superoxide scavenging activity were found to be 20.5, 40.5, 6.5 and 12.5 micro g/ml, respectively. Oral administration of the extracts (100 mg/kg body weight) reduced the blood sugar level in normal and in alloxan (120 mg/kg) diabetic rats significantly within 4 h. Continued, daily administration of the drug produced a sustained effect.     

Effects of oral administration of Gardeniae fructus extract and intravenous injection of crocetin on lipopolysaccharide- and prostaglandin E2-induced elevation of aqueous flare in pigmented rabbits

The purpose of this study was to evaluate the effects of extracts of Coptidis rhizoma, Phellodendri cortex and Gardeniae fructus, which are medicinal herbs in Orengedoku-to (Huanglin-Jie-Du-Tang in Chinese), and crocetin (a major component of Gardeniae fructus) on experimental elevation of aqueous flare in pigmented rabbits. To produce aqueous flare elevation, 0.5 microg/kg lipopolysaccharide (LPS) was injected into the ear vein, or prostaglandin E2 (PGE2) 25 microg/ml, was applied to the cornea by means of a glass cylinder. Animals were pretreated by oral administration of 150 g/day of food containing 0.15% (w/w) extract powder of Coptidis rhizoma, 0.10% (w/w) extract powder of Phellodendri cortex or 0.15% (w/w) extract powder of Gardeniae fructus for 4 days, or by intravenous injection of crocetin, 0.3, 3, 30 or 300 microg/kg, 30 minutes before aqueous flare elevation. Aqueous flare was measured with a laser flare-cell meter. Aqueous flare intensity was expressed as the area under the curve (AUC) in arbitrary units. The AUC of LPS- and PGE2-induced aqueous flare elevation was 4685 and 1386 arbitrary units, respectively. Pretreatment by oral administration of 0.15% (w/w) extract of Coptidis rhizoma or 0.10% (w/w) extract of Phellodendri cortex did not inhibit LPS-induced aqueous flare elevation. Pretreatment by oral administration of 0.15% extract of Gardeniae fructus suppressed LPS-induced aqueous flare elevation (AUC: 1411 arbitrary units). Pretreatment by intravenous injection of 3, 30 or 300 microg/kg of crocetin-inhibited LPS-induced aqueous flare elevation in a dose-dependent manner. Pretreatment with 3 or 30 microg/kg of crocetin did not inhibit PGE2-induced aqueous flare elevation, but 300 microg/kg of crocetin inhibited PGE2-induced aqueous flare elevation (AUC: 918 arbitrary units).     

Nardostachys jatamansi protects against liver damage induced by thioacetamide in rats

Nardostachys jatamansi is a medically important herb of Indian origin used for centuries in Ayurvedic and Unani systems of medicine for the treatment of various ailments. In the present paper, a 50% ethanolic extract of the rhizomes of N. jatamansi is shown to possess hepatoprotective activity. Pretreatment of rats with the extract (800 mg/kg body wt, orally) for three consecutive days significantly ameliorated the liver damage in rats exposed to the hepatotoxic compound thioacetamide. Elevated levels of serum transaminases (aminotransferases) and alkaline phosphatase, observed in thioacetamide alone treated group of animals, were significantly lowered in N. jatamansi pretreated rats. Pretreatment of the animals with the extract also resulted in an increase in survival in rats intoxicated with LD90 dose of the hepatotoxic drug.     

Chemopreventive activity of Withania somnifera in experimentally induced fibrosarcoma tumours in Swiss albino mice

The current experimental work deals with the chemopreventive studies of a hydroalcoholic extract of Withania somnifera roots, against 20-methylcholanthrene induced fibrosarcoma tumours in Swiss albino mice. A single subcutaneous injection of 200 microg 20-methylcholanthrene in 0.1 mL of dimethylsulphoxide into the thigh region of mice produced a high incidence (96%) of tumours. Oral treatment of animals with 400 mg/kg body weight of Withania somnifera extract (one week before injecting 20-methylcholanthrene and continued until 15 weeks thereafter) significantly reduced the tumour incidence, tumour volume and enhanced the survival of the mice, compared with 20-methylcholanthrene injected mice. The tumour incidence was also delayed in the treatment group when compared with 20-methylcholanthrene injected mice. Liver biochemical parameters revealed a significant modulation of reduced glutathione, lipid peroxides, glutathione-S-transferase, catalase and superoxide dismutase in extract treated mice compared with 20-methylcholanthrene injected mice. The mechanism of chemopreventive activity of Withania somnifera extract may be due to its antioxidant and detoxifying properties.     

Effects of Orthosiphon stamineus aqueous extract on plasma glucose concentration and lipid profile in normal and streptozotocin-induced diabetic rats

The objective of this study was to investigate the effects of Orthosiphon stamineus Benth. aqueous extract on plasma glucose concentration and lipid profile in normal and streptozotocin-induced diabetic rats. The chemical screening of the extract showed phenolic compound and flavonoid content were 13.24+/-0.33 mg/g and 1.73+/-0.14 microg/g, respectively. In oral glucose tolerance test, the extract (0.2-1.0 g/kg) significantly decreased plasma glucose concentration in a dose-dependent manner in both normal and diabetic rats. The extract at 1.0 g/kg was most effective in decreasing plasma glucose concentrations and the response was closed to the result of glibenclamide (5 mg/kg). After repeated daily oral administrations of the extract (0.5 g/kg) for 14 days, the extract significantly reduced plasma glucose concentration in diabetic rats at days 7 and 14. By the end of the study, plasma triglyceride concentration was lower in the extract-treated diabetic rats than untreated ones. Furthermore, plasma HDL-cholesterol concentration was significantly increased in diabetic rats treated with the extract. In perfused rat pancreas, the extract did not increase insulin secretion in the presence of 5.5 mM glucose, but 100 microg/ml extract potentiated glucose-induced insulin secretion. Our findings suggested that Orthosiphon stamineus aqueous extract is effective for alleviating hyperglycemia and improving lipid profile in diabetic rats.     

Anti-inflammatory and analgesic properties of the stem bark extract of Mitragyna ciliata (Rubiaceae) Aubrév. & Pellegr

Mitragyna ciliata is widely used in traditional medicine for the treatment of inflammation, hypertension, headache, rheumatism, gonorrhoea and broncho-pulmonary diseases. In the present study, the anti-inflammatory and analgesic properties of the stem bark extract of M. ciliata were investigated. The stem bark of this plant was extracted over Soxhlet with hexane followed by another extraction with methanol. The resulting methanol extract was used for the pharmacological test. Anti-inflammatory activity was evaluated on the basis of the inhibitory effect of the extract on 5-lipoxygenase, and carrageenin-induced hind paw oedema in the rat. The methanol extract, at a dose of 19.2 microg/ml, exhibited no inhibition on 5-lipoxygenase. However, this extract administered per os (50 mg/kg) produced about 70% inhibition of carrageenin-induced paw oedema 1 h after administration. This inhibition was maintained to about 50% 2 h after administration. The dose of 50 mg/kg of MeOH extract significantly decreased sensitivity to pain from 78.75 to 107.5 g These findings suggest that extracts of the bark of M. ciliata, possess potent anti-inflammatory and analgesic effects. Chemical analysis of the extract showed the presence of alkaloids and kaempferol derivative which may be responsible for the anti-inflammatory properties.     

The isoflavones mixture from Trifolium pratense L. protects HCN 1-A neurons from oxidative stress

Oxidative stress-induced neuronal cell death has been implicated in different neurological disorders and neurodegenerative diseases such as Alzheimer's disease and Parkinson's. Using the Alzheimer's disease-associated hydrogen peroxide (H(2)O(2)), we investigated the neuroprotective efficacy of a natural mixture of phytoestrogenic isoflavones (genistein, daidzein, biochanin A and formononetin) from Trifolium pratense L. (Red clover) against oxidative stress-induced cell death in human cortical cell line HCN 1-A maintained in culture. Neuronal viability was determined by MTT or trypan blue test and neuronal integrity by morphological analysis.The results obtained indicate that exposure of HCN 1-A cell cultures to hydrogen peroxide resulted in a concentration-dependent decrease in neuron viability. Concentration of H(2)O(2) ranging from 50 to 200 microg/ml were toxic to these cultures. A 24-hour pretreatment with 0.5, 1 and 2 microg/ml isoflavones extract significantly increased cell survival as evidenced by MTT or trypan blue test and significantly prevented the morphological disruption caused by H(2)O(2) as shown by microscopical inspection, indicating that neurons treated with isoflavones were protected from the cell death induced by H(2)O(2) exposure. These findings imply that the neuroprotective effect of isoflavones extract is partly associated with its antioxidant activity. Further, results of these investigations indicate that although isoflavones extract exert a neuroprotective effect, it do not promoted cortical neuron process outgrowth.     

Evaluation of antidepressant activity of methanolic and hydroalcoholic extracts of Acorus calamus L. rhizome through tail suspension test and forced swimming test of mice

ObjectiveAcorus calamus (AC) L. (Araceae) is an annual semi-aquatic and aromatic plant found in Europe, North America and Asia. Its rhizomes are often used by Native Americans, Americans, and Chinese as well as by other cultures. Ethnobotanical studies and documents have shown their use in various disease treatments, such as insomnia, mental disorders, diabetes mellitus, epilepsy, inflammation, asthma, neuropathic pain, and diarrhea. In this study, the antidepressant activity of methanolic and hydroalcoholic extracts of the AC rhizome part in mice was investigated.MethodsThree doses of methanolic extract of AC rhizome (MEACR) (25, 50 and 100 mg/kg b.wt), three doses of hydroalcoholic extract of AC rhizome (HAACR) (100, 200 and 400 mg/kg b.wt), and standards (imipramine, 15 mg/kg b.wt and fluoxetine, 20 mg/kg b.wt) was daily oral administration to the mice for consecutive 14 days. The extract effect on the immobility time was monitored by a tail suspension test (TST) and a forced swimming test (FST). Monoamine oxidase (MAO) levels were also analyzed using standard methods.ResultsThe optimum antidepressant activity was viewed at 100 mg/kg b.wt of MEACR extract and 400 mg/kg b.wt of HAACR extract with 23.82% and 20.59% immobility period reduction, respectively. Besides, the extracts weakened the FST-induced elevation of MAO activity significantly and returned to near-normal levels of neurotransmitters in the brain. 100 mg/kg b.wt or above of MEACR extract significantly prevented the MAO-A and MAO-B activities in mice brain at a dose-dependent fashion. But, just 400 mg/kg b.wt of HAACR extract prevented the activity of MAO-A and MAO-B. Fluoxetine and imipramine showed a tendency to prevent the activity of MAO-A and MAO-B.ConclusionThis study suggests that AC rhizome extract mediated antidepressant activity by modulating the central neurochemical and hypothalamic-pituitary-adrenal (HPA) axis in response to FST and TST-induced stress. Therefore, AC rhizome extract can be used as a valuable plant supplement to treat depressive disorders.     

Evaluation of the radioprotective action of geriforte in mice exposed to different doses of gamma-radiation

The effect of 5, 10, 20, 40 and 80 mg/kg b. wt. of hydroalcoholic extract of geriforte (an Ayurvedic herbal medicine) administered intraperitoneally was studied on the radiation-induced mortality in mice exposed to 10 Gy of gamma-radiation. Treatment of mice with different doses of geriforte consecutively for 5 days before irradiation delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls. A maximum protection was observed for 10 mg/kg geriforte, where a highest number of survivors were reported by 30 days post-irradiation and further experiments were carried out using this dose of geriforte. The mice were treated with 10 mg/kg b. wt. geriforte or double distilled water (DDW) and exposed to 7, 8, 9, 10 and 11 Gy of gamma radiation and observed for the induction of symptoms of radiation sickness and mortality up to 30 days post-irradiation. The geriforte treatment protected the mice against the GI death as well as bone marrow deaths and the dose reduction factor (DRF) was found to be 1.14. Toxicity study showed that geriforte was non-toxic up to a dose of 4250 mg/kg, where no drug-induced mortality was observed. The LD50 dose of geriforte was found to be 4750 mg/kg b. wt. To understand the mechanism of action of geriforte, free radical scavenging activity of the drug was evaluated. Geriforte was found to scavenge *OH, O2*- ABTS*+ and NO* in a dose-dependent manner. Our study demonstrates that geriforte is a good radioprotective agent and the optimum protective dose of 10 mg/kg was 1/475th of the LD50 dose.     

Evaluation of medicinal plants from Mali for their in vitro and in vivo trypanocidal activity

Water, methanol and dichloromethane extracts prepared from various parts of 40 medicinal plant species from Mali were investigated for their trypanocidal activity against Trypanosoma brucei brucei. Of a total of 165 extracts tested in vitro in the Low Inoculation Long Incubation Test (LILIT), 24 extracts showed a high trypanocidal activity. Using the Long-Term Viability Assay (LtVA) for corroboration of the results of the 24 extracts, it was found that 15 samples had minimum inhibitory concentration (MIC) values > 10 microg/ml, eight MIC values of 100 microg/ml and one MIC values of 50-100 microg/ml. So far, four extracts with MIC values < or = 100 microg/ml were tested for antitrypanosomal activity in mice, experimentally infected with Trypanosoma brucei brucei. Only, the aqueous extracts of the leaves of Terminalia avicennioides Guill. and Perr. (Combretaceae) and the stem bark of Ceiba pentandra (L.) Gaertn. (Bombacaceae) were able to reduce the parasitaemia in animals treated at the dose of 100 mg/kg b.w. (intraperitoneally, two times daily for 3 days) and of 150 mg/kg b.w. (per os, two times daily for 3 days), respectively. The reduction of parasitaemia was, however, statistically significant (p=0.002) only in case of treatment with Terminalia avicennioides.     

The evaluation of the radioprotective effect of chyavanaprasha (an ayurvedic rasayana drug) in mice exposed to lethal dose of gamma-radiation: a preliminary study

The effect of various doses of 50% ethanolic extract of chyavanaprasha (an Ayurvedic rejuvenating herbal preparation) was studied on the survival of mice exposed to 10 Gy of gamma-radiation. Treatment with chyavanaprasha, consecutively for fi ve days before irradiation, delayed symptoms of radiation sickness and onset of mortality when compared with the non-drug treated irradiated controls. All doses of chyavanaprasha provided a significant protection against gastrointestinal (GI) death (death of animals within 10 days after exposure to radiation), however, highest protection against GI death was observed for 15 mg/kg chyavanaprasha. Chyavanaprasha also provided a significant protection against the bone marrow death after 10 to 40 mg/kg. However, the best protection was seen for 15 mg/kg, where the highest number of survivors was observed at the end of 30 days post-irradiation. The drug was non-toxic up to a dose of 6 g/kg b. wt., the highest drug dose that could be tested. Our study demonstrates that chyavanaprasha can provide good radioprotection at a very low non-toxic dose.     

Antiovulatory faculty of the flower of Malvaviscus conzattii

The methanol extract of the flowers of Malvaviscus conzattii was orally administered in cycling unilaterally ovariectomized (ULO) rats at a dose level of 1 g/kg body wt/day for one or two cycles. The effect of the extract on the length of the cycle and ULO-induced compensatory ovulation and hypertrophy of the remaining ovary was assessed on the first oestrus following completion of treatment. Although no adverse influence was observed on either of the parameters, the cycle length was significantly prolonged and both the compensatory phenomena underwent significant inhibition after treatment of the extract for two consecutive cycles. In another experiment, the extract was found to be ineffective in preventing exogenous gonadotropin(s)-induced ovulation in immature and sub-adult rats. It is, therefore, suggested that the extract might have interfered with the synthesis and/or release of gonadotropin(s) from the pituitary while the ovarian utilization of gonadotropin(s) remained unaffected. The LD50 of the extract was found to be 20 g/kg body wt.