Preliminary study of hypoxia-related cardiovascular mediator-markers in patients with end-stage renal disease with and without diabetes and the effects of haemodialysis

Why Is COVID-19 More Severe in Patients With Diabetes? The Role of Angiotensin-Converting Enzyme 2, Endothelial Dysfunction and the Immunoinflammatory System

Meta-analyses have indicated that individuals with type 1 or type 2 diabetes are at increased risk of suffering a severe form of COVID-19 and have a higher mortality rate than the non-diabetic population. Patients with diabetes have chronic, low-level systemic inflammation, which results in global cellular dysfunction underlying the wide variety of symptoms associated with the disease, including an increased risk of respiratory infection. While the increased severity of COVID-19 amongst patients with diabetes is not yet fully understood, the common features associated with both diseases are dysregulated immune and inflammatory responses. An additional key player in COVID-19 is the enzyme, angiotensin-converting enzyme 2 (ACE2), which is essential for adhesion and uptake of virus into cells prior to replication. Changes to the expression of ACE2 in diabetes have been documented, but they vary across different organs and the importance of such changes on COVID-19 severity are still under investigation. This review will examine and summarise existing data on how immune and inflammatory processes interplay with the pathogenesis of COVID-19, with a particular focus on the impacts that diabetes, endothelial dysfunction and the expression dynamics of ACE2 have on the disease severity.

Serum vascular endothelial growth factor level is elevated in patients with impaired glucose tolerance and type 2 diabetes mellitus

Objective

This study was performed to investigate the serum vascular endothelial growth factor (VEGF) levels in Chinese patients with impaired glucose tolerance (IGT) and newly diagnosed type 2 diabetes mellitus (T2DM).

Methods

A total of 189 subjects (41 controls, 40 patients with IGT, and 108 patients with newly diagnosed T2DM) were recruited. Serum VEGF levels were determined by ELISA; other metabolic parameters were assessed by standard laboratory methods.

Results

There were significant differences in serum VEGF levels among the T2DM, IGT, and control groups (T2DM vs. controls: 72.00 [45.40, 98.35] pg/mL vs. 53.10 [36.30, 116.25] pg/mL; IGT vs. controls: 78.17 [55.52, 137.25] pg/mL vs. 53.10 [36.30, 116.25] pg/mL). Moreover, serum VEGF levels were positively associated with the homeostasis model assessment for insulin resistance (HOMA-IR) value. Multiple linear regression analysis indicated that the HOMA-IR value was an independent risk factor for elevated serum VEGF level.

Conclusions

Both IGT and T2DM patients exhibited increased serum VEGF levels, compared with controls; increased serum VEGF level was positively associated with the HOMA-IR value. Therefore, the increased serum VEGF level might partially result from increased insulin resistance in these patients.