Enteromorpha prolifera oligomers relieve pancreatic injury in streptozotocin (STZ)-induced diabetic mice

Carbohydr Polym. 2019 Feb 15:206:403-411. doi: 10.1016/j.carbpol.2018.11.019. Epub 2018 Nov 11.

Abstract

The polysaccharides of Enteromorpha prolifera (PEP) displayed various bioactivities such as anti-viral, anti-inflammatory and immune-regulative effects. However, no studies were performed on the biological effect of Enteromorpha prolifera oligomers (EPO). In this study, we prepared EPO and evaluated their anti-diabetic effect. By enzymatic degradation, EPO were produced from PEP, and the average molecular weight was identified to be 44.1 kDa by Gel Permeation Chromatography (GPC) analysis. The major monosaccharide units of EPO were measured to be rhamnose, glucuronic acid, glucose, xylose and galactose by capillary electrophoresis assay. Based on the in vitro studies, EPO presented potent reducing power and antioxidant effect such as the scavenging of 1, 1-diphenyl-2-picrylhydrazyl (DPPH), superoxide and NO radicals. The in vivo studies show that EPO relieved the symptoms of polydipsia, polyphagia, emaciation and hyperglycemia in streptozotocin (STZ)-induced diabetic mice to a certain extent. Further, by using the quantitative real-time PCR (qPCR) assay and immunofluorescence staining, EPO was proved to promote the insulin secretion by reducing pancreatic inflammation and apoptosis in diabetic mice. In summary, our results indicate that the mitigation of EPO on pancreatic damage might be an effective way to ameliorate the diabetes mellitus.

Keywords: Antioxidation; Apoptosis; Diabetes mellitus; Enteromorpha prolifera oligomers; Inflammation.

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Blood Glucose / drug effects
  • Diabetes Mellitus, Experimental / chemically induced
  • Diabetes Mellitus, Experimental / drug therapy*
  • Free Radical Scavengers / chemistry
  • Free Radical Scavengers / therapeutic use*
  • Hydrolysis
  • Hypoglycemic Agents / chemistry
  • Hypoglycemic Agents / therapeutic use*
  • Inflammation / drug therapy
  • Insulin / metabolism
  • Male
  • Mice, Inbred C57BL
  • Oligosaccharides / chemistry
  • Oligosaccharides / therapeutic use*
  • Oxidation-Reduction
  • Pancreas / drug effects
  • Pancreas / pathology
  • Polysaccharides / chemistry
  • Streptozocin
  • Ulva / chemistry*

Substances

  • Blood Glucose
  • Free Radical Scavengers
  • Hypoglycemic Agents
  • Insulin
  • Oligosaccharides
  • Polysaccharides
  • Streptozocin