In vivo and in vitro evaluation of the effects of Urtica dioica and swimming activity on diabetic factors and pancreatic beta cells

Abstract

Background: Urtica dioica (UD) has been identified as a traditional herbal medicine. This study aimed to investigate the effect of UD extract and swimming activity on diabetic parameters through in vivo and in vitro experiments.

Methods: Adult WKY male rats were randomly distributed in nine groups: intact control, diabetic control, diabetic + 625 mg/kg, 1.25 g/kg UD, diabetic + 100 mg/kg Metformin, diabetic + swimming, diabetic + swimming 625 mg/kg, 1.25 g/kg UD, and diabetic +100 mg/kg Metformin + swimming. The hearts of the animals were punctured, and blood samples were collected for biochemical analysis. The entire pancreas was exposed for histologic examination. The effect of UD on insulin secretion by RIN-5F cells in 6.25 or 12.5 mM glucose dose was examined. Glucose uptake by cultured L6 myotubes was determined.

Results: The serum glucose concentration decreased, the insulin resistance and insulin sensitivity significantly increased in treated groups. These changes were more pronounced in the group that received UD extract and swimming training. Regeneration and less beta cell damage of Langerhans islets were observed in the treated groups. UD treatment increased insulin secretion in the RIN-5F cells and glucose uptake in the L6 myotubes cells.

Conclusions: Swimming exercises accompanied by consuming UD aqueous extracts effectively improved diabetic parameters, repaired pancreatic tissues in streptozotocin-induced diabetics in vivo, and increased glucose uptake or insulin in UD-treated cells in vitro.

Keywords: Cholesterol; Diabetes; Insulin resistance; Pancreatic islet beta cells; Swimming exercise; TG; Urtica dioica.

Fig. 1

Chromatogram showing total ions of fiftheen herbicides and degradation products in standard solution

Fig. 2

Effect of UD extract on glucose stimulated insulin release in RIN5 cells. Data were expressed as mean ± SD for 6 replicates. LD; low dose of UD-treated (1.5 mg/ml), HD; high dose of UD-treated (3 mg/ml). *P value less than 0.05 considered as significant comparing low dose and high dose of UD extract with untreated

Fig. 3

Effect of UD extract on glucose uptake in L6 myotubes. Data were expressed as mean ± SD for 6 replicates. LD; low dose of UD-treated (1.5 mg/ml), HD; high dose of UD-treated (3 mg/ml). *P value less than 0.05 considered as significant comparing low dose and high dose of UD extract with untreated

Fig. 4

Comparison of the effect of UD extracts, swimming exercise and metformin treatment on the islets diameter in normal and diabetic rats; a: negative control; b: diabetic control; c: diabetic group with UD 0.625 mg/kg treated; d: diabetic group with UD 1.25 g/kg treated; e: diabetic group with metformin treated; f: diabetic group + exercise; g: diabetic group with 0.625 mg/kg treated + exercise; h: diabetic group with 1.25 g/kg treated + exercise; i: diabetic group with metformin treated + exercise (haematoxylin and eosin, original magnification × 400)