Curcumin improves the effect of a reduced insulin dose on glycemic control and oxidative stress in streptozotocin‐diabetic rats

Abstract

Insulin with natural antioxidants is emerging as a combination treatment for diabetes mellitus that attempts to exert effective glycemic control without adverse effects. The present study aimed to investigate the additive effects on metabolic disturbances, oxidative damage, and antioxidant defenses in streptozotocin-diabetic rats treated with curcumin and a reduced insulin dose. The best results were obtained in the treatment of diabetic rats with 4-U/day insulin; however, the glycemia levels in these rats were lower than those in normal rats, indicating a risk of hypoglycemia. Isolated treatments using curcumin or insulin in a reduced dose (1 U/day) decreased glycemia, dyslipidemia, and biomarkers of liver and kidney damage and increased the activity of hepatic antioxidants (superoxide dismutase and glutathione peroxidase), however, only to a lesser extent than 4-U/day insulin, without improvements in catalase activity or plasma lipid peroxidation. Decreases in glycemia, dyslipidemia, and tissue damage markers were more evident in the curcumin + 1-U/day insulin treatment than those seen in isolated treatments. The activity of hepatic antioxidants, including catalase, was further increased, and biomarkers of oxidative damage were decreased. Curcumin with a reduced insulin dose appears to be a promising strategy for combating the complications associated with diabetes and oxidative stress.

Curcumin combined with metformin decreases glycemia and dyslipidemia, and increases paraoxonase activity in diabetic rats

“…It must be highlighted that none of these curcumin doses caused toxicity in normal or diabetic rats. In further studies, when 90 mg/kg curcumin was administered in combination with carotenoids, lycopene or bixin [7], or with insulin [6], the effectiveness of curcumin was also observed in STZ-diabetic rats, and these combined treatments were able to add new benefits to combat the complications of diabetes associated with oxidative stress. In the present study, STZ-diabetic rats treated with curcumin-enriched yoghurt for 30 days showed maintenance of the glycemia values throughout the experimental period, in comparison with the progressive increase in the glycemia of DYOG rats, demonstrating the beneficial effects of curcumin on glycemic control (Fig.…”

“…Focusing on diabetes, curcumin has gained attention due to its ability to ameliorate hyperglycemia and exert a range of beneficial effects on macro- and microvascular complications, including cardiovascular diseases [2], nephropathy [3], retinopathy [4], and endothelial dysfunction [5]. Furthermore, studies are showing promising findings on the efficacy of curcumin in combination with antidiabetic agents [6] or with other phytochemicals [7] in the control of glycemia and attenuating other diabetic complications.…”

Curcumin protects bone biomechanical properties and microarchitecture in type�2 diabetic rats with osteoporosis via the TGFβ/Smad2/3 pathway

“…Recently, it has been reported that certain herbal extracts may prevent bone loss and protect against diabetes-induced bone microarchitecture disruption (21,22). Cur is an extract from the roots of the genus Curcuma and previous studies have revealed that it can reduce inflammation and oxidative stress in a diabetic rat model, improve islet cell function and reduce blood glucose levels (23,24). In addition, Cur may improve diabetes-induced damage of the retina, heart, kidney and other organs, thus demonstrating promising therapeutic effects against diabetic complications (25,26).…”

Nanocurcumin: A Promising Candidate for Therapeutic Applications

“…Wojcik et al, 2018;Gutierres et al, 2019;Den Hartogh et al, 2020 A Details of molecular targets mediated by curcumin (A) and important physico-chemical properties and their role in biological functions to remember when producing an effective nanoformulation of curcumin (B).…”