Role of CaMKII in diabetes induced vascular injury and its interaction with anti-diabetes therapy.

Diabetes mellitus is a metabolic disorder denoted by chronic hyperglycemia that drives maladaptive structural changes and functional damage to the vasculature. Attenuation of this pathological remodeling of blood vessels remains an unmet target owing to paucity of information on the metabolic signatures of this process. Ca2+/calmodulin-dependent kinase II (CaMKII) is expressed in the vasculature and is implicated in the control of blood vessels homeostasis. Recently, CaMKII has attracted a special attention in view of its chronic upregulated activity in diabetic tissues, yet its role in the diabetic vasculature remains under investigation.This review highlights the physiological and pathological actions of CaMKII in the diabetic vasculature, with focus on the control of the dialogue between endothelial (EC) and vascular smooth muscle cells (VSMC). Activation of CaMKII enhances EC and VSMC proliferation and migration, and increases the production of extracellular matrix which leads to maladaptive remodeling of vessels. This is manifested by activation of genes/proteins implicated in the control of the cell cycle, cytoskeleton organization, proliferation, migration, and inflammation. Endothelial dysfunction is paralleled by impaired nitric oxide signaling, which is also influenced by CaMKII signaling (activation/oxidation). The efficiency of CaMKII inhibitors is currently being tested in animal models, with a focus on the genetic pathways involved in the regulation of CaMKII expression (microRNAs and single nucleotide polymorphisms). Interestingly, studies highlight an interaction between the anti-diabetic drugs and CaMKII expression/activity which requires further investigation. Together, the studies reviewed herein may guide pharmacological approaches to improve health-related outcomes in patients with diabetes.

Targeting p75 neurotrophin receptors ameliorates spinal cord injury-induced detrusor sphincter dyssynergia in mice.

AIMS: To determine the role of p75 neurotrophin receptor (p75NTR ) and the therapeutic effect of the selective small molecule p75NTR modulator, LM11A-31, in spinal cord injury (SCI) induced lower urinary tract dysfunction (LTUD) using a mouse model. METHODS: Adult female T8 -T9 transected mice were gavaged daily with LM11A-31 (100 mg/kg) for up to 6 weeks, starting 1 day before, or 7 days following injury. Mice were evaluated in vivo using urine spot analysis, cystometrograms (CMGs), and external urethral sphincter (EUS) electromyograms (EMGs); and in vitro using histology, immunohistochemistry, and Western blot. RESULTS: Our studies confirm highest expression of p75NTRs in the detrusor layer of the mouse bladder and lamina II region of the dorsal horn of the lumbar-sacral (L6 -S1 ) spinal cord which significantly decreased following SCI. LM11A-31 prevented or ameliorated the detrusor sphincter dyssynergia (DSD) and detrusor overactivity (DO) in SCI mice, significantly improving bladder compliance. Furthermore, LM11A-31 treatment blocked the SCI-related urothelial damage and bladder wall remodeling. CONCLUSION: Drugs targeting p75NTRs can moderate DSD and DO in SCI mice, may identify pathophysiological mechanisms, and have therapeutic potential in SCI patients.