C-reactive protein reduces protein S-nitrosylation in endothelial cells

NLRP3 inflammasome promotes diabetes-induced endothelial inflammation and atherosclerosis

BACKGROUND

NLRP3 inflammasome can be activated by high glucose and links inflammation and metabolic disease. This study aimed to investigate the role of NLRP3 inflammasome in hyperglycemia-induced endothelial inflammation and diabetic atherosclerosis.

METHODS

NLRP3 levels in peripheral blood mononuclear cell (PBMC) and plasma IL-1β level were measured in diabetes patients. The activation of NLPR3 was detected in diabetic ApoE-/- mice and human umbilical vein endothelial cells (HUVECs).

RESULTS

Compared with healthy controls, NLRP3 expression levels in PBMC and plasma IL-1β level were significantly higher in diabetes patients but considerably decreased after lifestyle interventions and medicine. Moreover, carotid atherosclerosis was significantly related to plasma IL-1β level in diabetes patients. In diabetic atherosclerosis mouse model, NLRP3 knockdown suppressed NLRP3 inflammasome activation, inhibited the expression of adhesion molecules ICAM-1 and VCAM-1 in intima, reduced atherosclerosis and stabilized atherosclerotic plaque. In vitro, the expression of NLRP3 inflammasome components and the secretion of IL-1β were augmented by high glucose in HUVECs. Moreover, either high glucose or IL-1β promoted the expression of adhesion molecules, which were suppressed by NLRP3 knockdown or IL-1β receptor antagonist.

CONCLUSION

These findings provide novel insights into pathological mechanisms of diabetic atherosclerosis and have potential therapeutic implications for cardiovascular complications in diabetes.

Insights into the molecular mechanisms of diabetes-induced endothelial dysfunction: focus on oxidative stress and endothelial progenitor cells

Diabetes mellitus is a heterogeneous, multifactorial, chronic disease characterized by hyperglycemia owing to insulin insufficiency and insulin resistance (IR). Recent epidemiological studies showed that the diabetes epidemic affects 382 million people worldwide in 2013, and this figure is expected to be 600 million people by 2035. Diabetes is associated with microvascular and macrovascular complications resulting in accelerated endothelial dysfunction (ED), atherosclerosis, and cardiovascular disease (CVD). Unfortunately, the complex pathophysiology of diabetic cardiovascular damage is not fully understood. Therefore, there is a clear need to better understand the molecular pathophysiology of ED in diabetes, and consequently, better treatment options and novel efficacious therapies could be identified. In the light of recent extensive research, we re-investigate the association between diabetes-associated metabolic disturbances (IR, subclinical inflammation, dyslipidemia, hyperglycemia, dysregulated production of adipokines, defective incretin and gut hormones production/action, and oxidative stress) and ED, focusing on oxidative stress and endothelial progenitor cells (EPCs). In addition, we re-emphasize that oxidative stress is the final common pathway that transduces signals from other conditions-either directly or indirectly-leading to ED and CVD.