Intrauterine exposure to metformin: Evaluation of endothelial and perivascular adipose tissue function in abdominal aorta of adult offspring.

The biguanide metformin (MET) has been used during pregnancy for treatment of polycystic ovary syndrome and gestational diabetes. MET crosses the placenta and maternal treatment can expose the progeny to this drug during important phases of body development. Direct vascular protective effects have been described with the treatment of metformin. Nevertheless, it is unclear whether intrauterine exposure to metformin is safe for the vascular system of offspring. Thus, the present study aimed to investigate the intrinsic effects of metformin exposure in utero in the offspring abdominal aorta reactivity, in the presence and absence of perivascular adipose tissue (PVAT) and endothelium. For this, Wistar rats were treated with metformin 293 mg/kg/day (MET) or water (CTR) by gavage during the gestational period. The abdominal aorta reactivity to phenylephrine, acetylcholine, and sodium nitroprusside was evaluated in male adult offspring. It was observed that abdominal aorta relaxation was similar between MET and CTR groups in the presence or absence of PVAT. In addition, the contraction to phenylephrine was similar between MET and CTR groups in the presence and absence of PVAT and endothelium. Therefore, metformin exposure during pregnancy had no intrinsic effect on the offspring abdominal aorta PVAT and endothelial function, demonstrating it to be safe to the vascular system of the offspring.

Evaluation of antihyperglycaemic activity of Calotropis procera leaves extract on streptozotocin-induced diabetes in Wistar rats

Calotropis procera (Aiton) W.T.Aiton,Apocynaceae, popularly known as "algodão-de-seda", is a wild African bush, rich in bioactive substances that determine the medicinal potential of this species. Diabetes mellitus is a disease that affects about 10% of the population. This study aimed to evaluate the antihyperglycaemic activity of the hydroalcoholic extract of the leaves of C. procera of occurrence in coast of Pernambuco, Brazil. The hydroalcholic extract of the leaves of C. procera (300 and 600 mg/kg/day), vehicle, insulin (6U, s.c.) or metformin (500 mg/ kg/day) were administered orally to streptozotocin-induced diabetic rats (n = 7/group) for four weeks. Changes in body weight, food and water intake, biochemical markers, fasting glucose levels and oral glucose tolerance test were evaluated. The results showed that the C. procera dried extract (300 and 600 mg/kg) reduced significantly the level of blood glucose throughout the evaluation period and improved metabolic status of the animals and ameliorate the oral tolerance glucose test. The phytochemical screening revealed and quantified the presence of phenolic compounds and flavonoids in a percentage of 29.1 and 2.9%, respectively. Thus, we conclude that the extract of the leaves of C. procera has antihyperglycemic activity.

Anti-diabetic activity of an hexane extract of Prosthechea michuacana in streptozotocin-induced diabetic rats / Actividad antidiabética de un extracto de hexane de Prosthechea michuacana en ratas diabéticas inducidas por estreptozotocina

In this study we investigated the antihyperglycaemic, antihyperlipidaemic and antiglycation effects of some extracts of Prosthechea michuacana bulbs in normoglycemic and diabetic rats induced by streptozocin (STZ). Hexane, chloroform and methanol extracts of P. michuacana were screened for hypoglycemic activity, and biochemical parameters as serum triglycerides, total cholesterol, lipid peroxidation, liver glycogen, skeletal muscle glycogen levels, superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase activity in diabetic rats. Additionally we determined Glucose 6 Phosphatase and glucokinase activities in liver, inhibition of insulin and protein glycation. Glucose levels in blood plasma were determined by using GOD-POD method. Administration of chloroform and methanol extracts showed no effect on STZ induced diabetic rats (SD). On the other hand, treatment with hexane extract at 200 and 400 mg/kg doses, resulted in a reversal of diabetes and its complications. Both doses significantly brought down blood glucose concentration (35.75 and 47.78 percent in diabetic rats, 50.64 and 57.10 percent in nondiabetic rats), increased glycogenesis and decreased glyconeogenesis bringing the glucose metabolism toward normalcy. These doses also reversed the hyperlipidemia by reducing cholesterol (41.56 percent, 46.08 percent) and triglycerides (37.5 percent, 46.27 percent) and improved hepatic antioxidant enzyme activities. Its effect was compared with that of glibenclamide and tolbutamide, as reference antidiabetic drugs. The hexane extract decreased the hyperinsulinemia by 24 percent in SD and showed a significant change on AGEs formation in vitro with IC50 values of 48.3 ug/ml comparable to inhibitory effect of aminoguanidine with IC50 values of 27.2 ug/ml. It reduced HbA1C levels by 6.4 percent in chronic STZ-diabetic rats. It is concluded that hexane extract of Prosthechea michuacana bulbs possesses anti-hyperglycemic and antihyperlipemic...

En este estudio se determinaron los efectos antidiabéticos, antihiperlipidemico y glicación (AGEs) de algunos extractos de Prosthechea michuacana (PM) en ratas normoglucémicas y con diabetes inducida por estreptozotocina (STZ). Se probó el efecto de los extractos de hexano, cloroformo, metanol de PM sobre la actividad hipoglucemiante, la carga de glucosa, los parámetros bioquímicos tales como triglicéridos, niveles de colesterol total, peroxidación lipídica, glucógeno del hígado, los niveles de glucógeno muscular, niveles de superoxide dismutase, catalasa, glutation reductasa and glutation peroxidasa en ratas normales y diabéticas. También se determinó la glucosa 6 Phosphatasa y las actividades de GK en el hígado, la inhibición de la insulina y la glicosilación de las proteínas. Los niveles de glucosa sanguínea se determinaron por el método de GOD-POD. La administración de los extractos de cloroformo y metanol no presentaron ningún efecto sobre la SD, en cambio el tratamiento con el extracto de hexano (PM) a dosis de 200 y 400 mg/kg, inhibió la diabetes y sus complicaciones. Ambas dosis redujeron significativamente los niveles de glucosa sanguínea (35.75 y 47.78 por ciento en las ratas diabéticas, 50.64 y 57.10 por ciento en las ratas diabéticas), el aumento de la glucogénesis y la disminución de la gluconeogénesis conduce el metabolismo de la glucosa hacia la normalidad. Estas dosis disminuyeron la hiperlipidemia reduciendo el colesterol (41.56 por ciento, 46.08 por ciento) y los triglicéridos (37.5 por ciento, 46.27 por ciento) así como también mejoran las actividades antioxidantes de las enzimas hepáticas. Su efecto se comparó con la glibenclamida y tolbutamida, fármacos usados como antidiabeticos. El extracto de hexano disminuyo la hiperinsulinemia en un 24 por ciento en SD. PM mostró un cambio significativo in vitro sobre la formación de los AGEs con valores de IC50 de 48.3 mg/ml comparable al efecto inhibidor de la aminoguanidina con valores de IC50 de...