Effect of hawthorn seed extract on the gastrointestinal function of rats with diabetic gastroparesis

Abstract

Diabetic gastroparesis (DGP) is a common chronic complication of diabetes mellitus. Its pathogenesis is related to many factors. Hawthorn seeds are the seeds of Crataegus pinnatifida Bunge, which has many chemical constituents and pharmacological properties. In this study, we investigated the therapeutic effect and potential mechanism of ethyl acetate extract from hawthorn seeds (HSEAE) on DGP rats. We measured their body weight, blood sugar, gastric emptying rate, and intestinal propulsion rate, as well as the effects of HSEAE on superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) in gastric homogenate. The levels of ghrelin in rat plasma were determined by radioimmunoassay, while those of motilin (MTL) and gastrin (GAS) were determined by enzyme-linked immunosorbent assay. Western blot was used to detect the expression of c-kit, ghrelin, and neuronal nitric oxide synthase (nNOS) in the rats’ stomachs, and immunohistochemistry was used to detect changes in interstitial cells of Cajal (ICC). The results showed that different doses of HSEAE effectively promoted the gastric emptying and small intestinal propulsion (P < 0.05 or P < 0.01). In addition, HSEAE increased SOD and GSH-Px in the rats’ stomachs while decreasing MDA, and increased plasma ghrelin while decreasing MTL and GAS (P < 0.05 or P < 0.01). The expression of c-kit, ghrelin, and nNOS proteins and the number of ICCs in the rats’ stomachs also significantly increased (P < 0.05 or P < 0.01). Our experiments showed that HSEAE improved gastrointestinal motility in DGP rats, and its potential mechanism might be involved in the inhibition of oxidative stress injury induced by hyperglycemia, upregulating n-NOS, c-kit expression, and ICCs in their stomachs and regulating gastrointestinal hormones.