Agomelatine is an extremely potent agonist at both melatonin receptors (MT1 and MT2), with additional antagonism at 5HT2C. It is a novel antidepressant with many desired in vivo properties, including neuroprotection and neurogenesis in depression-sensitive brain areas. Agomelatine′s efficacy appears to be due to both melatonergic and serotonergic properties. In neurogenesis assays, both in vitro and in vivo, the compound effects were differentially affected by antagonists for MT1/MT2 and 5HT2C, demonstrating actions through all three receptors.
Oxidative modification of low-density lipoprotein (LDL) plays an important role in vascular dysfunction associated with diabetes mellitus. Gliclazide is a second-generation sulfonylurea with free-radical-scavenging activity. Incubation of human aortic smooth muscle cell (HASMC) with native human LDL (100 μg/mL) in the presence of increasing concentrations of gliclazide (1 to 10 μg/mL) resulted in a dose-dependent decrease in HASMC-mediated LDL oxidation. Exposure of HASMCs to gliclazide (1 to 10 μg/mL) and native LDL (100 μg/mL) also led to a dose-dependent decrease in oxidized LDL-induced human monocyte adhesion to HASMCs. In addition, incubation of HASMCs with gliclazide dramatically reduced the ability of oxidized LDL to stimulate the proliferation of these cells. Finally, treatment of HASMCs with gliclazide resulted in a marked decrease in oxidatively modified LDL-induced monocyte chemoattractant protein (MCP)-1 and human heat shock protein 70 (HSP 70) expression, both at the gene and protein levels. These results show that gliclazide, at concentrations in the therapeutic range (5 to 10 μg/mL), is effective in vitro in reducing vascular smooth muscle cell (VSMC) dysfunction induced by oxidatively modified LDL. Administration of gliclazide to type 2 diabetic patients could form part of the strategy for the prevention and management of diabetic cardiovascular diseases