ABSTRACT
ABSTRACT Diabetes is a metabolic disease caused by abnormal insulin secretion or action. In the present study, the effects of betulinic acid (BA, a triterpene) are evaluated on glucose, α-amylase and plasma insulin levels, insulin resistance and the histopathology of pancreatic islets in streptozotocin-nicotinamide (STZ-NA) diabetic mice. Seventy adult male NMRI mice were randomly divided into seven groups: control, sham, diabetic, diabetic treated with BA (10, 20 and 40 mg/kg) and diabetic treated with metformin (200 mg/kg). Diabetes was induced in mice by intraperitoneal injection of streptozotocin 50 mg/kg after a dose of nicotinamide 120 mg/kg. Two weeks after treatment with BA, blood samples were collected for measuring glucose, α-amylase and insulin levels, and the pancreas was isolated for histopathology evaluation. Diabetes reduced the number and diameter of pancreatic islets, and increased α-amylase and insulin resistance. BA treatment reduced blood glucose, α-amylase and improved insulin sensitivity as well as pancreas histopathology. In addition, BA showed stronger effects on the pancreatic histology and insulin resistance compared to the metformin group
Subject(s)
Animals , Male , Mice , Streptozocin , Niacinamide , Diabetes Mellitus, Experimental/prevention & control , Triterpenes/classification , Diabetes Mellitus/chemically induced , Hypoglycemic Agents/adverse effectsABSTRACT
Maytenus ilicifolia and Maytenus aquifolia species are widely used as a cicatrisation agent, an anti-spasmodic, contraceptive, antiulcerogenic, diuretic and analgesic. Considering the importance of these species in popular medicine, this work is focused on the determination of the chemical content of tannins and the triterpenes friedelan-3-one, friedelan-3-ol and friedelin in 15 native populations of Maytenus ilicifolia distributed in the south and mind-west regions of Brazil. Correlation of the concentration of these compounds with the environmental parameters such as average annual temperature, climate, vegetation, geomorphology, latitude and altitude was determined using Pearson's coefficient. Results showed that average annual temperature and climate have significant effect on tannin content at a 95% confidence level. The highest tannin concentration was found in Ponta Porã population, and for the triterpenes investigated, a significant correlation between their concentrations with the environmental variables studied was not verified.
As espécies de Maytenus ilicifolia e Maytenus aquifolia são utilizadas como antiespasmódico, contraceptivo, antiulcerogênico, diurético, cicatrizante e analgésico. A ação antiulcerogênica dos extratos de Maytenus ilicifolia possuem relação com a presença de taninos e com os triterpenos friedelan-3-ona, friedelan-3-ol e friedelin. Este trabalho está focado na determinação do teor de taninos e dos triterpenos friedelan-3-ona, friedelan-3-ol e friedelin em 15 populações nativas de Maytenus ilicifolia distribuídas nas regiões Sul e Centro-Oeste do Brasil. A correlação entre a concentração destes compostos com variáveis ambientais, tais como temperatura média anual (TMA), clima segundo Koeppen, vegetação, geomorfologia, latitude e altitude foi determinada através do emprego da correlação de Pearson. Os resultados mostraram que as variáveis temperatura média anual e clima apresentaram influência significativa ao nível de confiança de 95% sobre a concentração de taninos. O maior teor de taninos foi encontrado na população de Ponta Porã, a qual possui uma temperatura média anual de 23 °C. Para os triterpenos estudados, friedelan-3-ona, friedelan-3-ol e friedelin, não foi evidenciada correlação significativa entre a concentração destes compostos com as variáveis ambientais estudadas.