Impact of Polyphenols on Inflammatory and Oxidative Stress Factors in Diabetes Mellitus: Nutritional Antioxidants and Their Application in Improving Antidiabetic Therapy

Abstract

Diabetes mellitus is a chronic metabolic disorder characterized by hyperglycaemia and oxidative stress. Oxidative stress plays a crucial role in the development and progression of diabetes and its complications. Nutritional antioxidants derived from dietary sources have gained significant attention due to their potential to improve antidiabetic therapy. This review will delve into the world of polyphenols, investigating their origins in plants, metabolism in the human body, and relevance to the antioxidant mechanism in the context of improving antidiabetic therapy by attenuating oxidative stress, improving insulin sensitivity, and preserving β-cell function. The potential mechanisms of, clinical evidence for, and future perspectives on nutritional antioxidants as adjuvant therapy in diabetes management are discussed.

Keywords: diabetes; inflammation; oxidative stress; polyphenols.

Figure 1

Sources of reactive oxygen species in the cell.

Figure 2

Types of ROS-mediated DNA damage based on Bui et al. [44].

Figure 3

Pathways leading to advanced glycation end products (AGEs). Glu-AGE—glucose-derived AGE; Fru-AGE—fructose-derived AGE.

Figure 4

Molecular mechanisms correlating oxidative stress, its outcomes, and hyperglycaemia, which lead to insulin resistance and T2DM development. Abbreviations: TLRs—Toll-like receptors; Nf-κb—nuclear factor kappa b; MAPK—mitogen-activated kinases. Legend: ↓—decrease, ↑—increase.

Figure 5

General mechanism for obtaining glutathione disulphide. GSH—glutathione; GS-SG—glutathione disulphide.

Figure 6

Structures of example polyphenols.