Silymarin improves the behavioural, biochemical and histoarchitecture alterations in focal ischemic rats: a comparative evaluation with piracetam and protocatachuic acid.

Comparative neuroprotective potential of silymarin, piracetam and protocatechuic acid ethyl ester (PCA) was evaluated in focal ischemic rats. Various pharmacological, biochemical (lipid peroxidation, reduced glutathione, catalase, nitrite content, brain water content) and behavioural (memory impairment, motor control, neurological score) including infarct size and histopathological alterations were evaluated. Silymarin (200mg/kg) and PCA treatment significantly improved behavioural, biochemical and histopathological changes, and reduced water content and infarct size. However, piracetam only improved behavioural and histopathological changes, reduced water content and infarct size. The findings indicate that silymarin exhibits neuroprotective activity better than PCA and piracetam in focal ischemia/reperfusion reflected by its better restoration of behavioural and antioxidant profile.

Anti-inflammatory and analgesic activity of protocatechuic acid in rats and mice.

Anti-inflammatory and analgesic activity of protocatechuic acid (PCA), a natural product, was evaluated in different rat models (viz., carrageenan-induced paw oedema, cotton pellet-induced granuloma and Freund's adjuvant arthritis) of inflammation and chemical and heat induced mouse models of pain. Treatment with PCA inhibited significantly different biological parameters like hind paw oedema, granuloma exudates formation and arthritis index in carrageenan oedema, cotton pellet granuloma and Freund's adjuvant arthritis, respectively. The biochemical changes viz., glutathione, superoxide dismutase, catalase, lipid peroxidation and NO in oedematous or in liver tissues and serum alanine aminotransferase and lactic dehydrogenase occurred during different types of inflammation were either significantly restored or inhibited with PCA pretreatment. Present experimental findings demonstrate promising anti-inflammatory and analgesic activity of PCA which is comparable with that of standard drugs used.

Evaluation of anti-migraine potential of Areca catechu to prevent nitroglycerin-induced delayed inflammation in rat meninges: possible involvement of NOS inhibition.

ETHNOPHARMACOLOGICAL RELEVANCE: Areca catechu nut extract is a popular folk remedy for the treatment of migraine in Kerala and Tamil Nadu states of India. AIM OF THE STUDY: In order to prove the claimed utilization of plant, the effect of hydroalcoholic extract of Areca catechu nut (ANE) was investigated in nitroglycerine induced inflammation in rat meninges. In these models infusion of nitric oxide donor glyceryl trinitrate (GTN) produces augmented plasma protein extravasation (PPE) in dura mater, provides an important substrate for the development of migraine in rats. MATERIALS AND METHODS: The effect on plasma protein extravasation was assessed in both the models of intravenous and topical GTN application following oral administration of ANE (250 mg/kg and 500 mg/kg) in both curative and preventive treatment and compared with that of control positive. The l-NAME (15 mg/kg, i.v.) was used as reference standard. Plasma protein extravasation was measured using fluorescein as marker and was measured using a Perkin-Elmer LS-30 luminescence spectrometer. RESULTS: Expression of iNOS in the spleen after intravenous injection produced PPE into the dura mater in control positive group was significantly (P<0.01) reduced to 1.553±0.02499 and 1.398±0.01887 by preventive treatment with ANE at the dose of 250 and 500 mg/kg, orally, respectively. The extravasation produced by topical GTN due to expression of iNOS in dural macrophages was also reduced to 1.555±0.03384 and 1.425±0.01204 by preventive treatment with ANE at the dose of 250 and 500 mg/kg, orally, respectively. While ANE do not showed any significant results in curative treatment in both the models of i.v. and topical GTN application. CONCLUSION: These findings collectively indicate that the extract exhibited significant inhibition of iNOS, which may be the probable mechanism for its anti-migraine activity, providing evidence, at least in part, for its folkloric use.

Potential analgesic, anti-inflammatory and antioxidant activities of hydroalcoholic extract of Areca catechu L. nut.

The hydroalcoholic extract of Areca catechu L. (ANE) nut was screened for its analgesic, anti-inflammatory and in vitro antioxidant potential. Three doses of ANE (250, 500 and 1000 mg/kg orally) were tested for analgesic and anti-inflammatory activities. Evaluation of analgesic activity of ANE was performed using hot plate and formalin test in mice. ANE showed maximum increase in hot plate reaction time (56.27%, p<0.01), while reduced the duration of licking/biting behaviors in first (39.45%, p<0.05) and second (92.71%, p<0.01) phases of the formalin test indicating significant analgesic activity. ANE reduced the paw edema considerably (86.79% inhibition after 24h, p<0.01) in dose-dependent manner compared to carrageenan-induced rat. In addition, in vitro antioxidant activity of ANE was investigated by total phenolic content (TPC) and hydrogen peroxide assay. The IC(50) observed in hydrogen peroxide assay was 83.14 µg/ml and TPC 120.56±21.09 mg QE/g. Altogether, these results suggest that the hydroalcoholic extract of Areca catechu could be considered as a potential analgesic, anti-inflammatory and antioxidant agent.