Hypoglycemic effect of Malmea depressa, a plant used in the treatment of Type 2 Diabetes in Yucatan, Mexico

Diabetes mellitus type 2 (DMT2), is characterized by tissue insulin resistance combined with a relative deficiency in insulin secretion. An individual may present primarily with insulin resistance or beta cell deficiencies, and these abnormalities can range from mild to severe. DMT2 is one of the most prevalent health problems in Mexico. As a result of the application of the Disease-Consensus Index, Malmea depressa R. E. Fries, (Annonaceae) (MD) was selected as the prominent specie traditionally used in a Mayan community to treat DMT2.

The acute and chronic hypoglycemic effects were confirmed in neonatally streptozotocin induced diabetic rats (n5-STZ), thereafter was determined whether MD would reduce hepatic glucose production by targeting gluconeogenesis. The effect of the plant extracts on gluconeogenesis (in vivo), and the activity over Glucose-6-Phosphatase (in vitro) were examined. Furthermore, the phytochemical composition of the plant was analysed.

From the pharmacological active fractions, two Phenylbutane derivatives (2-Hydroxy-3,4,5-trimethoxy-1-(2',4'-hydroxy-3'-dihydroxy) butyl-benzene and 2-Hydroxy-3,4,5-trimethoxy-1-(2',3',4'-hydroxy)butyl-benzene) as well as a phenylpropane derivative, 3-(3-hydroxy-2,4,5-trimethoxyphenyl) propane-1,2 diol, were isolated. To assess the degree of inhibition of glucose-6-phosphate hydrolysis, we plotted a dose-response curve; the ethanolic extract poses an IC50 of 267.62 (µg/ml).

The results suggest that administration of MD can improve glycemic control by blocking hepatic glucose production, especially in the fasting state. These data support its traditional use as an infusion consumed continually throughout the day.