NADPH oxidase: A membrane-bound enzyme and its inhibitors in diabetic complications

Area of Science:

• Biochemistry
• Pathophysiology
• Pharmacology

Background:

• Oxidative stress, an imbalance between reactive oxygen species (ROS) and antioxidant defenses, is implicated in various diseases.
• Diabetes mellitus is characterized by hyperglycemia, leading to increased ROS generation and oxidative stress.
• Diabetic vasculopathy, encompassing micro- and macrovascular complications, is a major consequence of prolonged hyperglycemia.

Purpose of the Study:

• To review the role of Nicotinamide adenine dinucleotide phosphate oxidase (NOX) in the development of diabetic complications.
• To explore the pathways associated with NOX activation in hyperglycemia.
• To discuss the potential of NOX inhibitors in managing and treating diabetic complications.

Main Methods:

• This review synthesizes existing literature on NOX enzymes and their involvement in diabetes.
• It examines the molecular mechanisms linking hyperglycemia, NOX activation, and downstream pathological pathways.
• The review also covers current and potential therapeutic strategies involving NOX inhibition.

Main Results:

• Hyperglycemia activates NOX enzymes, leading to excessive ROS production.
• NOX activation is associated with pathways like aldose reductase, advanced glycation end products, protein kinase C, and the hexosamine pathway.
• NOX overexpression promotes inflammation, endothelial dysfunction, hyperlipidemia, and collagen deposition, contributing to diabetic complications.

Conclusions:

• NOX enzymes are critical mediators of hyperglycemia-induced oxidative stress and diabetic complications.
• Targeting NOX pathways with inhibitors offers a promising therapeutic approach for diabetic nephropathy, retinopathy, neuropathy, and cardiomyopathy.
• Further research into NOX inhibitors is warranted for effective management of diabetic vascular complications.