The number of people with diabetes rose from 108 million in 1980 to 422 million in 2014. In 2019, an estimated 1.5 million deaths were directly caused by diabetes. There are a number of diabetic complications. Among them, the most prevalent microvascular complications are kidney disease, blindness, and amputations, with current therapies only slowing disease progression. Heart attacks, stroke, neuropathy, skin and foot diseases are also serious complications of diabetes.

Biomarkers and intracellular and extracellular signaling pathways have important roles in the diagnosis and prognosis of diabetes and its complications, as well as identifying individuals who exhibit a high risk for diabetes development. For example, alanine aminotransferase, uric acid and vitamin D are closely related to the occurrence of T2DM (type 2 diabetes mellitus). Albuminuria strongly predicts the progression of diabetic kidney disease (DKD). In addition, the rapidly developed genomics, transcriptomics, proteomics, metabolomics, and immunology provided new ideas and platforms for the research of diabetes mellitus in recent years.

The aim of this Special Issue is to invite authors to submit original research and review articles that provide novel findings of biomarkers as well as cellular and molecular mechanisms involved in the field of diabetes mellitus and its complications. Insights in the areas of effective targeted theranostic strategies and other investigating challenges and opportunities associated with targeting therapy are also welcome.

Potential topics include but are not limited to the following:

• Novel biomarkers and targets of diagnosis and treatment for diabetes mellitus and its complications
• The functions and roles of diabetic biomarkers
• Intracellular and extracellular signaling pathways and small molecule inhibitors in diabetes mellitus
• The molecular mechanism of vascular aging in diabetes mellitus
• Regulatory roles of non-coding RNAs and exosomes in diabetes mellitus
• The study of single-cell RNA sequencing, bulk RNA sequencing, and spatial transcriptomics for diabetes mellitus
• Regulatory roles of immune cells for diabetes mellitus
• Animal models for in vivo imaging and quantification analysis in diabetes mellitus