Antipyretic and antimalarial activities of Solenostemon monostachyus.

CONTEXT: Solenostemon monostachyus P. Beauv (Lamiaceae) is an important herb used traditionally in the treatment of malaria, fever, and other diseases. OBJECTIVES: Antiplasmodial and antipyretic activities of S. monostachyus aerial extract were evaluated to ascertain the folkloric claim of its antimalarial and antipyretic activities. MATERIALS AND METHODS: The extract (75-225 mg/kg) and fractions (chloroform and aqueous; 150 mg/kg) of S. monostachyus were investigated for suppressive, prophylactic, and curative antiplasmodial activities against chloroquine-sensitive Plasmodium berghei infections in Swiss albino mice and for antipyretic activity against 2,4-dinitrophenol and yeast-induced pyrexia. Artesunate (5 mg/kg) and pyrimethamine (1.2 mg/kg) were used as positive controls for antiplasmodial models. Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice. RESULTS: The extract/fractions progressively reduced parasitaemia induced by chloroquine sensitive P. berghei infection in prophylactic (28.48-71.72%), suppressive (12.52-72.47%), and curative (22.4-82.34%) models in mice. These reductions were statistically significant (p < 0.01-0.001). They also improved significantly (p < 0.01-0.001) the mean survival time (MST) from 12.26 to 25.63 d relative to control (11.36 d). The activities of extract/fractions were incomparable with that of the standard drugs used (artesunate and pyrimethamine). The extract exerted prominent inhibition of pyrexia on dinitrophenol (87.33-90.11%, 5 h) and yeast (56.22-65.33, 5 h) induced pyrexia. Inhibition was significant (p < 0.05-0.001) from 3 to 5 h post-administration of extract and in a dose-dependent fashion. CONCLUSION: The plant may possess antiplasmodial and antipyretic effects which may in part be mediated through the chemical constituents of the plant.

Anti-inflammatory and antinociceptive activities of Solenostemon monostachyus aerial part extract in mice.

OBJECTIVE: Solenostemon monostachyus is used in traditional medicine for the treatment of various ailments such as ulcer, hypertension, pains and inflammatory diseases. Evaluation of anti-inflammatory and analgesic activities of S. monostachyus aerial parts was carried out to ascertain its uses in traditional medicine. MATERIALS AND METHODS: The aerial parts of S. monostachyus was cold extracted by soaking the dried powdered material in ethanol. The aerial parts crude extract (75 -225 mg/kg) of S. monostachyus was investigated for analgesic and anti-inflammatory activities using various experimental models; acetic acid, formalin and thermal- induced pains models for analgesic study and carrageenin, egg albumin and xylene - induced edema models for anti-inflammatory investigation. RESULTS: The extract caused a significant (p<0.05 - 0.001) dose-dependent reduction of inflammation and pains induced by different phlogistic agents used. These effects were comparable to those of the standard drug, (ASA, 100 mg/kg) used in some models. CONCLUSION: The anti-inflammatory and analgesic effects of this plant may in part be mediated through the chemical constituents of the plant and the results of the analgesic action suggest central and peripheral mechanisms. The findings of this work confirm the ethno medical use of this plant to treat inflammatory conditions.