Cooked common beans (Phaseolus vulgaris) protect against β-cell damage in streptozotocin-induced diabetic rats

Plant Foods Hum Nutr. 2013 Jun;68(2):207-12. doi: 10.1007/s11130-013-0353-1.


Diabetes is a disease characterized by a hyperglycemic stage that leads to a chronic inflammatory state. We evaluated the in vivo effect of a diet supplemented with 25 % cooked black bean cultivar Negro 8025 (N8025) flour in streptozotocin-induced diabetic rats. The effect was assessed before (preventive-treatment) and after (treatment) the onset of diabetes. There is a significant decrease of total phenolic, tannins and anthocyanins content after cooking, and the concentration of most of the single phenols analyzed are only slightly decreased. The treatment group showed a significant reduction of glucose (22.8 %), triglycerides (21.9 %), total cholesterol (29.9 %) and LDL (56.1 %) that correlates with a protection of pancreatic ß-cells. The diet with N8025 flour before the induction of diabetes did not exert a protective effect (glucose levels are similar to the diabetic control) but they have low levels of total cholesterol (47.5 %) and LDL (56.1 %). The preventive-treatment group did not inhibit the increase of TNF-α and IL-1β, whereas the treatment group did, compared to the diabetic control. Therefore, N8025 bean supplementation can be recommended to control diabetes.

MeSH terms

  • Animals
  • Anthocyanins / analysis
  • Cholesterol / metabolism
  • Cooking
  • Diabetes Mellitus, Experimental / diet therapy*
  • Diabetes Mellitus, Experimental / metabolism
  • Diabetes Mellitus, Experimental / pathology
  • Diabetes Mellitus, Experimental / prevention & control
  • Glucose / metabolism
  • Hypoglycemic Agents / pharmacology
  • Insulin-Secreting Cells / drug effects*
  • Lipid Metabolism / drug effects
  • Male
  • Pancreas / drug effects
  • Pancreas / pathology
  • Phaseolus* / chemistry
  • Phenols / analysis
  • Rats, Wistar
  • Streptozocin
  • Tannins / analysis
  • Triglycerides / metabolism
  • Tumor Necrosis Factor-alpha / metabolism


  • Anthocyanins
  • Hypoglycemic Agents
  • Phenols
  • Tannins
  • Triglycerides
  • Tumor Necrosis Factor-alpha
  • Streptozocin
  • Cholesterol
  • Glucose