Effect of Calendula officinalis hydroalcoholic extract on serum levels of TNF-α, glucose and leptin in male rats with type 1 diabetes

Abstract

Purpose: High blood glucose levels in chronic diabetes mellitus cause multiple complications including increased inflammatory factors such as TNF-α and decreased leptin levels in blood and other tissues. Therefore, it is important to reduce the destructive effects of these factors. Herbal drugs are considered to reduce complications of diabetes. In this regard, the effects of hydroalcoholic extract of calendula officinalis in some tissues have been observed and it has been suggested that it may be effective in reversing the levels of leptin and TNF-α. Therefore, in this study, the effects of hydroalcoholic extract of calendula officinalis on blood glucose, TNF-α, and leptin were investigated in diabetic male rats.

Methods: Sixty male Wistar rats weighing 300-250 g were divided into 6 groups in equal and random order: healthy group, diabetic group, diabetic group with normal saline gavage, and 3 diabetic groups receiving extract of calendula officinalis with doses of 100, 150, and 250 mg / kg/day. Diabetes was induced by injection of 60 mg / kg Streptozotocin (Sigma-Germany). The duration of treatment of rats was 4 weeks. To measure the variables, after anesthetizing the animals, the blood sample was collected to determine serum levels of TNF-α and leptin, and fasting glucose levels.

Results: : The body weight of diabetic rats after 4 weeks of intervention was significantly less than that of control rats, and treatment with extract of calendula officinalis had no significant effect on the weight of rats. Meanwhile, induced diabetes significantly increased fasting blood glucose in diabetic groups than in the control group. In diabetic groups receiving the extract of calendula officinalis, fasting blood sugar decreased significantly compared to diabetic control group. TNF-α levels increased in diabetic condition, and treatment of diabetic rats with extract of calendula officinalis decreased this inflammatory factor. Serum leptin decreased by induction of diabetes compared to healthy control group, but the extract of calendula officinalis did not significantly affect the level of this hormone. Conclusion: The extract of calendula officinalis showed some anti-diabetic properties such as decreasing blood glucose and anti-inflammatory effects and reduced TNF-α, an important inflammatory marker for the pathogenesis of diabetes, with no significant effect on serum leptin levels.