Neuroprotective Effect of Astragalus Polysacharin on Streptozotocin (STZ)-Induced Diabetic Rats

Med Sci Monit. 2019 Jan 5:25:135-141. doi: 10.12659/MSM.912213.

Abstract

BACKGROUND In the recent years, there has been increasing interest in traditional Chinese medicine as a neuroprotective nutrient in the management of chronic neurodegenerative disease, such as diabetic cognitive decline. Astragalus polysacharin (APS), a Chinese herb extract, is a biologically active treatment for neurodegenerative diseases. Therefore, in the present study, we investigated the neuroprotective effects of APS (20 mg/kg) on diabetes-induced memory impairments in Sprague-Dawley (SD) rats and explored its underlying mechanisms of action. MATERIAL AND METHODS Thirty SD rats were randomly divided into a control group (CON group, n=10), a diabetic model (DM) group (n=10), and an APS group (n=10). We administered 55 mg/kg streptozotocin (STZ, Sigma) by intraperitoneal injection to induce a diabetic model. Food and water intake, body weight, and blood fasting plasma glucose (FPG) were measured. The Morris water maze test (MWM) was used to assess learning and memory ability, and we measured levels of N-methyl-D-aspartate receptor (NMDA), calcium/calmodulin-dependent protein kinase II (CaMKII), and cAMP response element-binding protein (CREB) in the hippocampus. RESULTS APS (20 mg/kg) administration decreased the rats' fasting plasma glucose (FPG) levels and body weight. APS (20 mg/kg) administration improved the cognitive performance of diabetes-induced rats in the Morris water maze test. APS (20 mg/kg) administration reduced the number of dead cells in the CA1 region of the hippocampus. Furthermore, APS (20 mg/kg) administration obviously upregulated the phosphorylation levels CREB, NMDA, and CaMK II. CONCLUSIONS These results suggest that APS has the neuroprotective effects, and it may be a candidate for treatment of neurodegenerative diseases such as diabetic cognitive impairment.

MeSH terms

  • Animals
  • Astragalus Plant / chemistry*
  • Astragalus Plant / metabolism
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / analysis
  • Cognitive Dysfunction / metabolism
  • Cyclic AMP Response Element-Binding Protein / analysis
  • Diabetes Mellitus, Experimental / metabolism
  • Diabetes Mellitus, Experimental / physiopathology
  • Drugs, Chinese Herbal / pharmacology
  • Hippocampus / metabolism
  • Hippocampus / physiology
  • Male
  • Maze Learning / drug effects
  • Memory / drug effects*
  • Neuroprotective Agents / pharmacology*
  • Plant Extracts / pharmacology
  • Plant Roots / chemistry
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, N-Methyl-D-Aspartate / analysis
  • Streptozocin

Substances

  • Creb1 protein, rat
  • Cyclic AMP Response Element-Binding Protein
  • Drugs, Chinese Herbal
  • Neuroprotective Agents
  • Plant Extracts
  • Receptors, N-Methyl-D-Aspartate
  • Streptozocin
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2