Evaluation of the Effectiveness of Metformin and Black Rice Ethanol Extract Combination in Reducing Blood Glucose Levels and Protecting Kidney, Liver, and Pancreatic Cells


  • Arifah S. Wahyuni Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, Universitas Muhammadiyah Surakarta, Sukoharjo, 57162 Indonesia
  • Diski W. Wijianto Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, Universitas Muhammadiyah Surakarta, Sukoharjo, 57162 Indonesia
  • Dhani Iswanto Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, Universitas Muhammadiyah Surakarta, Sukoharjo, 57162 Indonesia




Metformin, Diabetes Mellitus, Black Rice Bran, Antioxidant, Alloxan


Metformin (MET), a first-line oral antidiabetic medicine, is known for its ability to increase insulin sensitivity. However, uncontrolled lactic acidosis, a potential side effect of MET, can cause organ injury. On the other hand, antioxidants like black rice bran (BRB), containing cyanidin-3-glucosidase (C3G), have demonstrated efficacy in preventing diabetic kidney injury and fibrosis due to oxidative stress. The objective of this study is to investigate the potential of combining the ethanol extract of black rice bran (EEBRB) with MET in the regulation of various parameters in hyperglycemic rats. In this study, 20 male rats were divided into different groups. They were treated for 21 days after being divided into the normal group, alloxan (ALX) group 150 mg/kg BW, MET 63 mg/kg BW, and a combination of MET 63 mg/kg BW and EEBRB 50 mg/kg BW. The results of the study indicate that both treatments properly controlled fasting blood glucose levels with no hypoglycemia over a duration of 21 days. Furthermore, histopathological examinations revealed significant protection against kidney, liver, and pancreatic injury in the group receiving the combination treatment. Although there was no statistically significant weight loss, the combination did not lead to excessive weight gain, a common concern with some antidiabetic medications. MET and EEBRB can regulate blood glucose levels and attenuate organ damage in animals with hyperglycemia. Further investigation is necessary to elucidate the processes underlying the safety and efficacy of the combination approach.


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How to Cite

Wahyuni, A. S., Wijianto, D. W., & Iswanto, D. (2024). Evaluation of the Effectiveness of Metformin and Black Rice Ethanol Extract Combination in Reducing Blood Glucose Levels and Protecting Kidney, Liver, and Pancreatic Cells. Tropical Journal of Natural Product Research (TJNPR), 8(6), 7410–7415. https://doi.org/10.26538/tjnpr/v8i6.11