Antidiabetic effects of Scrophularia striata ethanolic extract via suppression of Pdx1 and Ins1 expression in pancreatic tissues of diabetic rats

Abstract

One of the factors that causes severe metabolic imbalance and abnormal changes in many tissues, especially in the pancreas, is the pathological disease of diabetes mellitus. Therefore, in this study, the therapeutic effects of Scrophularia striata were investigated using an animal model in the control of diabetic injury and pancreatic complications caused by diabetes. A total of 66 rats (weight 220-250 g) were randomly divided into: Healthy Control group (rats without diabetes receiving Propylene glycol as solvent); Diabetic control group; 3 experimental healthy groups (receiving the extract with doses of 100, 200 and 400 mg/kg bw/day); 3 treatment groups; and3 pretreatment groups. Diabetes was induced in rats by intraperitoneal STZ (60 mg/kg bw). FBS, HbA1c and insulin were measured after 4 weeks. Pdx1 and Ins1 gene expression was assessed by RT-PCR. The histological evaluation was also performed with H&E staining. The data were analyzed by SPSS ver20 using ANOVA and Tukey tests. By treatment with S. striata ethanolic extract, these factors were close to the normal range. The expression of the Pdx1 and Ins1 genes increased in the treated rats with S. striata extract. Analysis of the obtained data indicates the effect of S. striata in improving the complications of diabetes in rats and can be considered for therapeutic purposes.

Figure 1

The effect of S. striata extracts on Insulin, FBS and HbA1c. Data are expressed as the mean ± SD; n = 6 for each group. 100, S. striata 100 mg/kg bw; 200, S. striata 200 mg/kg bw; 400, S. striata 400 mg/kg bw. Significant differences compared to the Sham and Control groups were shown P ≤ 0.05 *, and P ≤ 0.05**, respectively. ANOVA and Tukey’s were applied to evaluate the data.

Graph 1

The results of gene expression.

Figure 2

Histopathological findings of the effects of Scrophularia striata ethanolic extract on pancreas tissues of studied groups. 28 days after the experiment, pancreas tissues samples were evaluated Harris-Eosin hematoxylin staining (A) Sham, (B) Control, (C) Experimental healthy (healthy + Scrophularia striata 400 mg/kg), (D) Pre-treatment (treated before and after STZ injection with S. striata 400 mg/kg), (E) Treatment (diabetic + S. striata 400 mg/kg). No histopathological changes were observed in pancreas tissues with sham (A) and experimental healthy (C) islets of Langerhans (arrows) and ascites is seen in a normal pattern. In the control group (B) degeneration in the cells of the islets of Langerhans (arrows), and atrophy and fibrosis in the structure of the pancreas is shown. In the pre-treatment group (D) normal condition of the ascites is shown. All these lesions were markedly attenuated in S. striata treatment (400 mg/kg) (E) (H&E *200).