Antinociceptive and hypoglycaemic evaluation of Conyza filaginoides (D.C.) Hieron Asteraceae.

This work was undertaken to assess the antinociceptive and hypoglycaemic properties of a quantified extract of Conyza filaginoides (CFOE), as well as the antinociceptive potential of rutin, the main active compound of the plant, in normoglycaemic and/or hyperglycaemic mice (nicotinamide-streptozotocin, NA-STZ). The antinociceptive effect of CFOE was evaluated using the writhing, hotplate and formalin tests in mice. Rutin was also examined with the formalin test. In addition, the antihyperalgesic effect of CFOE was evaluated in hyperglycaemic mice. The hypoglycaemic effect of CFOE was tested using an acute hypoglycaemic assay, and oral glucose and sucrose tests in normoglycaemic and hyperglycaemic mice. CFOE showed antinociceptive effect when tested in normoglycaemic mice in the writhing and hotplate tests (31.6-316 mg/kg). CFOE was also active in both normoglycaemic and hyperglycaemic mice in the formalin test (10-100 μg/paw) revealing its antihyperalgesic property. Rutin reduced the nociceptive behaviour in the formalin test; its mechanism of action seems to involve GABAergic and opioid pathways. CFOE possessed noted hypoglycaemic and antihyperglycaemic effects in normoglycaemic and hyperglycaemic mice (31.6-316 mg/kg). The antinociceptive, antihyperalgesic and hypoglycaemic effects of C. filaginoides found in this study support the contemporary uses of the plant in Mexican folk medicine.