• VIJAYAKRISHNA P Pharmacovigilance Physician, Vigi Medsafe, Hyderabad, Telangana, India.
  • USHASREE TS Department of Pharmacology, ESIC Medical College, Hyderabad, Telangana, India.
  • INDIRA K Department of Pharmacology, Government Medical College, Nizamabad, Telangana, India.
  • AVULA NAVEEN Department of Pharmacology, Government Medical College, Nizamabad, Telangana, India.
  • SHIRISHA S Pharmacovigilance Physician, Vigi Medsafe, Hyderabad, Telangana, India.


Objectives: Diabetes mellitus (DM) is a spectrum of common metabolic disorders, arising from a variety of pathogenic mechanisms resulting in hyperglycemia that causes chronic micro- and macro-vascular complications. Vitamin C is structurally similar to glucose and can replace it in many chemical reactions and thus is effective in the prevention of non-enzymatic glycosylation of proteins. Hence, the present study taken up to see the effect of supplementation of Vitamin C on blood glucose and glycosylated hemoglobin (HbA1c) along with metformin in experimentally-induced diabetic rabbits.

Methods: Twenty-four adult New Zealand white rabbits (1.5–2.5 kg) were divided into four groups, each containing six rabbits. Group 1: Normal control (distilled water); Group 2: Metformin (23.33 mg/kg) is given orally; Group 3: Metformin (23.33 mg/kg) plus Vitamin C 250 mg are given orally; and Group 4: Metformin (23.33 mg/kg) plus Vitamin C 500 mg are given orally. Animals were treated for 30 days. The blood samples were collected on days 0 and 30 from the marginal ear vein of rabbits for the estimation of blood glucose and HbA1c levels.

Results: Statistically analyzed by ANOVA test followed by post hoc Tukey’s test using GraphPad Prism software. Results shown that Vitamin C 500 mg oral supplementation with metformin had very highly significantly reduced HbA1c levels by 40.12% (p = 0.0001***) and blood glucose levels by 49.12% (p = 0.0003***), whereas Vitamin C 250 mg oral supplementation with metformin also significantly reduced HbA1c levels by 25.49% (p = 0.0001***) and blood glucose levels by 42.95% (p = 0.0026**) when compared to metformin alone, which reduced HbA1c levels by 22% (p = 0.0001***) and blood glucose levels by 39.58% (p = 0.0001***).

Conclusion: Oral supplementation of Vitamin C 500 mg/250 mg to the metformin was superior in reducing HbA1c levels and blood glucose levels compared to metformin alone in rabbits. Hence, Vitamin C oral supplementation may be helpful in lowering blood glucose levels and HbA1c levels and improving glycemic control in Type 2 DM.

Keywords: Alloxan, Blood glucose, Diabetic rabbits, Glycosylated hemoglobin, Metformin, Vitamin C


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How to Cite
P, V., U. TS, I. K, A. NAVEEN, and S. S. “EFFECT OF SUPPLEMENTATION OF VITAMIN C ON BLOOD GLUCOSE AND GLYCOSYLATED HEMOGLOBIN LEVELS IN EXPERIMENTALLY-INDUCED DIABETIC RABBITS”. Asian Journal of Pharmaceutical and Clinical Research, Vol. 13, no. 6, Apr. 2020, pp. 161-5, doi:10.22159/ajpcr.2020.v13i6.37617.
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