Stimulation of the peroxisome proliferator-activated receptor γ (PPARγ) and the expression of selected blood monocyte cytokine genes in diabetic macroangiopathy

Rhizoma Dioscoreae Nipponicae polysaccharides protect HUVECs from H2O2-induced injury by regulating PPARγ factor and the NADPH oxidase/ROS–NF-κB signal pathway

“…LDH levels were measured by enzyme kinetics methods. While SOD and GSH-Px are the antioxidant enzymes to prevent injuries from ROS on cell membrane (Atig et al, 2012;Yang et al, 2014). The density of culture serum SOD was determined using the xanthine oxidase method and and T-AOC is the index to measure the total antioxidant capacity of the whole cell (Tong et al, 2013) that can be determined by colorimetric method.…”

“…PPARg acts as an E3 ubiquitin ligase, physically interacting with p65 to induce its ubiquitination and degradation and this function is critical to terminate NF-kB signaling pathwayelicited inflammation and pro-oxidative events (Hou et al, 2012). Also PPARg activation has been established to have the potential to exert antiatherogenic effects in animal models of AS .…”

“…And it has been suggested that NF-kB is an oxidative stressresponsive transcription factor. NF-kB plays a critical role in the development of inflammatory response by up-regulating the expression of VCAM-1, ICAM-1 and E-selectin (Kang et al, 2003). As such, lowering of vascular wall ROS should reduce clinical complications associated with AS (Cersosimo and DeFronzo, 2006).…”

“…The bioactive constituents in Rhizoma Dioscoreae Nipponicae are mainly steroidal saponins and some researches indicated that the extractives of Rhizoma Dioscoreae Nipponicae could reduce serum glucose, neutral lipid, and total cholesterol levels of rats, also it could scavenge hydroxyl radicals (Wang et al, 2004;Jeon et al, 2006). However we found that polysaccharides from Rhizoma Dioscoreae Nipponicae also had stronger pharmacologic activities in our previous studies and polysaccharides from traditional Chinese herbs have been demonstrated that they could prevent AS by reducing inflammation and oxidative stress and decrease the level of serum lipid with less side-effects (Li et al, 2005;Park et al, 2010;Yang et al, 2013). Nevertheless, there are few studies on the molecular mechanisms of Rhizoma Dioscoreae Nipponicae polysaccharides (RDNP) in reducing inflammation and oxidative stress.…”

“…Nowadays, it has been proved that atherosclerosis (AS) is closely associated with systemic oxidative stress (Chisolm and Steinberg, 2000;Galkina and Ley, 2009) involving initial events of transendothelial migration of inflammatory cells into the vascular wall, the formation of fatty streaks, the later events including vascular cell activation and more complex lesion development. The oxidative modification hypothesis implicates reactive oxygen species (ROS) in the pathogenesis of AS.…”