2-Hydroxyl hispolon reverses high glucose induced endothelial progenitor
cell dysfunction through the PI3K/AKT/eNOS and AMPK/HO1 pathways
Abstract
Background and Purpose: In diabetes, elevated blood sugar (BS) levels
contribute to the overproduction of reactive oxygen species (ROS),
leading to endothelial progenitor cell (EPC) dysfunction. 2-hydroxy
hispolon (2HH), a derivative of Hispolon (HIS), shows potential in
reversing high glucose-induced EPC dysfunction. Experimental Approach:
In vitro, we inspected the effect of 2HH on three different angiogenic
cells, including outgrowth endothelial cell (OEC), circulating
angiogenic cell (CAC) and endothelial cell (EC). In vivo, High-fat diet
and streptozotocin induced diabetic mice and hindlimb ischemic model
were utilized to evaluate the effect of 2HH on angiogenesis and CAC
mobilization. Key Results: Treatment with 2HH significantly improved the
proliferation, migration, and tube formation, NO synthesis and ROS
diminishing of OEC under high glucose conditions. Moreover, 2HH
administration potentiates the AMP-activated protein kinase (AMPK)/heme
oxygenase-1 (HO-1) and phosphoinositide 3-kinases (PI3K)/protein kinase
B (AKT)/endothelial nitric oxide synthase (eNOS) signaling pathways in
OECs exposed to high glucose levels. Additionally, 2HH reverses high
glucose-induced impairment of CAC function but fails to restore EC
dysfunction under high glucose conditions. Hindlimb ischemic assay
demonstrated that 2HH treatment enhances blood flow recovery in ischemic
hindlimbs and increases the number of circulating CACs in diabetic mice
after femoral ligation. Conclusion and Implications: Our study has
demonstrated that 2HH effectively reduces oxidative stress, thereby
preventing EPC dysfunction induced by high glucose levels, primarily
through the PI3K/AKT/eNOS and AMPK/HO-1 pathways. These findings offer a
promising therapeutic avenue for attenuating the susceptibility to
critical limb ischemia in patients with diabetes.