Effects of three Mexican medicinal plants (Asteraceae) on blood glucose levels in healthy mice and rabbits.

The effects of Psacalium decompositum, Psacalium peltatum and Acourtia thurberi (Asteraceae) on blood glucose levels were investigated in fasting mice and temporally hyperglycemic rabbits. The root decoction of P. decompositum reduced the blood glucose of normal mice from 49.1 +/- 3.8 to 35.7 +/- 2.0 mg/dl after intraperitoneal administration (P < or = 0.005) and significantly lowered the hyperglycemic peak (17.1%) in rabbits with temporal hyperglycemia. P. peltatum and A. thurberi decoctions also diminished fasting glycemia in mice and hyperglycemia in rabbits, but the effects were minor. A preliminary phytochemical study using thin layer chromatography showed that water decoctions of the three roots contained alkaloids and sugars. P. decompositum and P. peltatum showed the presence of maturine. However, other furoeremophylanes, such as cacalol and cacalone were only present in P. decompositum. A. thurberi root water decoction showed the presence of the benzoquinone perezone, and its derivative pipitzol.