Oxidized low-density lipoprotein: A double-edged sword on atherosclerosis

Traditional Chinese Medicine-based Treatment in Cardiovascular Disease: Potential Mechanisms of Action

Cardiovascular Disease (CVD) is the leading cause of morbidity and death worldwide and has become a global public health problem. Traditional Chinese medicine (TCM) has been used in China to treat CVD and achieved promising results. Therefore, TCM has aroused significant interest among pharmacologists and medical practitioners. Previous research showed that TCM can regulate the occurrence and development of atherosclerosis (AS), ischemic heart disease, heart failure, myocardial injury, and myocardial fibrosis by inhibiting vascular endothelial injury, inflammation, oxidant stress, ischemia-reperfusion injury, and myocardial remodeling. It is well-known that TCM has the characteristics of multi-component, multi-pathway, and multitarget. Here, we systematically review the bioactive components, pharmacological effects, and clinical application of TCM in preventing and treating CVD.

Influence of Moxifloxacin on Hepatic Redox Status and Plasma Biomarkers of Hepatotoxicity and Nephrotoxicity in Rat

Moxifloxacin is a broad spectrum fluoroquinolone antibacterial agent. We examined the hepatic redox status and plasma biomarkers of nephrotoxicity and hepatotoxicity in rat following administration of moxifloxacin (MXF). Twenty-four Wistar rats, 180–200 g, were randomized into four groups (I–IV). Animals in group I (control) received 1 mL of distilled water, while animals in groups II, III, and IV received 1 mL each of MXF equivalent to 4 mg/kg b.w., 8 mg/kg b.w., and 16 mg/kg b.w., respectively. After seven days, plasma urea, bilirubin, and creatinine were significantly (P < 0.05) elevated in the MXF-treated animals. Activities of alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase were significantly increased in the plasma of MXF-treated animals compared to control. Also plasma total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglycerides increased significantly in the MXF-treated groups relative to control. Moreover, MXF triggered a significant decrease in hepatic catalase, superoxide dismutase, and glutathione-S transferase activities. Likewise, MXF caused a decrease in the hepatic levels of glutathione and vitamin C. A significant increase in hepatic MDA content was also observed in the MXF-treated animals relative to control. Overall, our data suggest that the half-therapeutic, therapeutic, and twice the therapeutic dose of MXF induced nephrotoxicity, hepatotoxicity, and altered hepatic redox balance in rats.

The association between adiponectin, HDL-cholesterol and α1-antitrypsin-LDL in female subjects without metabolic syndrome

Background

Oxidized low-density lipoprotein (LDL) may act as an atheroprotective (anti-atherosclerotic) agent under some conditions. While the α1-antitrypsin (AT)-LDL complex is considered a type of oxidized LDL, its clinical relevance remains unknown. The aim of the present study was to investigate the association between AT-LDL and anti-atherosclerotic variables such as HDL-cholesterol and adiponectin in subjects with and without metabolic syndrome (MetS).

Methods

In asymptomatic females (n = 194; mean age, 54 years) who were divided into non-MetS (n = 108) and MetS groups (n = 86), the fasting levels of serum AT-LDL, adiponectin and glucose/lipid panels were measured, in addition to body mass index (BMI) and blood pressure.

Results

The MetS group showed significantly higher BMI, blood pressure, glucose and triglyceride levels as well as significantly lower levels of HDL-cholesterol and adiponectin than the non-MetS group. A multivariate-adjusted analysis revealed that in the non-MetS group, AT-LDL was significantly, independently and positively correlated with adiponectin (β = 0.297, P < 0.05), along with HDL-cholesterol (β = 0.217, P < 0.05). In the MetS group, AT-LDL was significantly, independently and positively correlated with LDL-cholesterol only (β = 0.342, P < 0.05).

Conclusions

These data suggest that AT-LDL may exert anti-atherosclerotic effects in female subjects without MetS. More studies are required to clarify the clinical roles of AT-LDL in relation to the pathophysiology of MetS.

Nicotinamide adenine dinucleotide phosphate oxidase and diabetes: vascular implications

Vascular disease associated with diabetes mellitus is a major cause of morbidity and mortality and is increasing in the United States. It is now recognized that oxidative stress plays a substantial role in the underlying vascular pathology of several diseases, including hypertension and diabetes. In diabetes, there is an increase in the steady state levels of reactive oxygen species. One of the primary generators of reactive oxygen species is nicotinamide adenine dinucleotide phosphate oxidase. Studies have indicated that inhibition of this system is associated with vascular benefits in diabetes. Therefore, there may be a role for therapies directed at nicotinamide adenine dinucleotide phosphate oxidase in this disease. This review will examine the structure, activation, potential role in vascular disease, and benefits of inhibition of nicotinamide adenine dinucleotide phosphate oxidase.

Oxidized low density lipoprotein impairs endothelial progenitor cell function by downregulation of E-selectin and integrin alpha(v)beta5

BACKGROUND

Oxidized low density lipoprotein (oxLDL) has been shown to induce apoptosis and senescence of endothelial progenitor cells (EPC). In the present study, we hypothesized that even sub-apoptotic concentrations of oxLDL impair the angiogenic potential of EPC and investigated if this effect is mediated by affecting adhesion and incorporation.

METHODS

A co-culture system of human microvascular endothelial cells and EPC was used to study the effect of sub-apoptotic concentrations of native (nLDL) and oxLDL on cell-cell interaction. The expression and the functional role of angiogenic adhesion molecules and integrins was monitored by FACS and neutralizing assay, respectively.

RESULTS

We observed an inhibition of tube formation and impairment of EPC integration into the vascular network of mature endothelial cells by oxLDL. In contrast, nLDL did not affect angiogenic properties of EPC. Incubation of EPC with sub-apoptotic oxLDL concentrations significantly decreased E-selectin and integrin alpha(v)beta(5) expression (37.6% positive events vs. 71.5% and 24.3% vs. 49.9% compared to control culture media without oxLDL). Interestingly, expression of alpha(v)beta(3), VE-cadherin and CD31 remained unchanged. Blocking of E-selectin and integrin alpha(v)beta(5) by neutralizing antibody effectively inhibited adhesion of EPC to differentiated endothelial cells (56.5% and 41.9% of control; p<0.001).

CONCLUSION

In conclusion, oxidative alteration of LDL impairs angiogenic properties of EPC at sub-apoptotic levels by downregulation of E-selectin and integrin alpha(v)beta(5), both substantial mediators of EPC-endothelial cell interaction.