Retraction Note: Tert-butylhydroquinone lowers blood pressure in AngII-induced hypertension in mice via proteasome-PTEN-Akt-eNOS pathway.

This article has been retracted.

Tert-butylhydroquinone lowers blood pressure in AngII-induced hypertension in mice via proteasome-PTEN-Akt-eNOS pathway.

Tert-butylhydroquinone (tBHQ), as an antioxidant, has been widely used for many years to prevent oxidization of food products. The aim of this study was to investigate whether tBHQ activates endothelial nitric oxide synthase (eNOS) to prevent endothelial dysfunction and lower blood pressure. The role of Akt in tBHQ-induced eNOS phosphorylation was examined in human umbilical vein endothelial cells (HUVEC) or in mice. tBHQ treatment of HUVEC increased both Akt-Ser473 phosphorylation, accompanied with increased eNOS-Ser1177 phosphorylation and NO release. Mechanically, pharmacologic or genetic inhibition of Akt abolished tBHQ-enhanced NO release and eNOS phosphorylation in HUVEC. Gain-function of PTEN or inhibition of 26S proteasome abolished tBHQ-enhanced Akt phosphorylation in HUVEC. Ex vivo analysis indicated that tBHQ improved Ach-induced endothelium-dependent relaxation in LPC-treated mice aortic arteries, which were abolished by inhibition of Akt or eNOS. In animal study, administration of tBHQ significantly increased eNOS-Ser1177 phosphorylation and acetylcholine-induced vasorelaxation, and lowered AngII-induced hypertension in wildtype mice, but not in mice deficient of Akt or eNOS. In conclusion, tBHQ via proteasome-dependent degradation of PTEN increases Akt phosphorylation, resulting in upregulation of eNOS-derived NO production and consequent improvement of endothelial function in vivo. In this way, tBHQ lowers blood pressure in hypertensive mice.

Reduced apoptosis after acute myocardial infarction by simvastatin.

To observe the effect of simvastatin in patients with acute myocardial infarction in rabbits against myocardial apoptosis, and to explore its possible mechanism. Male New Zealand white rabbits were randomized into three groups, including the myocardial infarction group (12 rabbits), the simvastatin treatment group (15 rabbits), and the sham group (12 rabbits). In the simvastatin treatment and myocardial infarction groups, the rabbits received myocardial infarction surgeries. While in the sham group, loose knots were tied in the left anterior descending coronary artery branches. The simvastatin treatment group was given simvastatin by oral gavage 24 h after surgery. Parameters, which included left ventricular end-diastolic diameter, left ventricular end-systolic diameter, left ventricular ejection fraction, and left ventricular mass index, were recorded in these three groups. Edge myocardial infarction and myocardial cell apoptosis were analyzed using TUNEL assay, and Bcl-2, Bax, and Caspase-3 protein levels were detected by Western blot. Acute myocardial infarction model was successfully established in rabbits by ligation of the left anterior descending coronary artery. Compared with the myocardial infarction group, left ventricular end-diastolic diameter (LVEDD) and left ventricular end systolic diameter (LVESD) were significantly reduced and left ventricular ejection fraction (LVEF) increased in the simvastatin treatment group. Compared with the sham group, LVEDD and LVESD were significantly increased and LVEF decreased in the simvastatin treatment group. All the differences were statistically significant (P < 0.05). Left ventricular mass index in the simvastatin treatment group was statistically lower than the myocardial infarction group. Compared with the sham group, left ventricular mass index in both the simvastatin treatment and myocardial infarction groups was significantly increased. The differences of the above comparisons were statistically significant (P < 0.05). Compared with the sham group, the apoptosis rate of the myocardial infarction group and the simvastatin treatment groups was significantly increased as shown by TUNEL assay, however, the apoptosis rate of the simvastatin treatment group was significantly lower than that of the myocardial infarction group. All the differences among above comparisons were statistically significant (P < 0.05). Bcl-2 levels significantly increased in the simvastatin treatment group compared with the myocardial infarction group, but Bcl-2 levels in both groups were significantly lower than the sham group. However, Bax protein levels showed inverse expression with Bcl-2. Meanwhile, Caspase-3 protein expression showed similar trend with Bcl-2. Simvastatin can improve cardiac function after myocardial infarction and reduce apoptosis of myocardial cells, possibly by decreasing Bax and Caspase-3 expression and increasing the expression level of Bcl-2.

Association between arterial stiffness and risk of coronary artery disease.

OBJECTIVE: To investigate the role of Brachial ankle Pulse Wave Relocity (baPWV) and cfPWV on the risk of Coronary artery disease and the interaction between baPWV and risk factors of Coronary artery disease (CAD). METHODS: A case-control study was conducted at Department of Emergency, SunYat-Sen memorial Hospital, China. We collected 332 cases with coronary artery disease and 328 subjects without CAD between February 2012 and October 2013. A multivariate logistic regression analysis was performed to analyze the risk factors of CAD. RESULTS: CAD subjects were more likely to be old age, and have higher BMI, waist-hip ratio, hypertension, fasting glucose, TG, carotid-femoral PWV (cfPWV) and baPWV, and CAD subjects had a lower TC, HDL-C and LDL-C. We found that older age, smoking, higher hypertension, TC, TG, HDL-C, LDL-C, carotid-femoral PWV (CfPWV) and baPWV were associated with risk of CAD. baPWV had significant interaction with age, TC, TG, HDL-C and LDL-C, carotid-femoral PWV (cfWV) was correlated with age, HDL-C and LDL-C. CONCLUSION: This study showed that baPWV and cfPWV are two independent factors for the risk of Coronary artery disease, and baPWV and cfPWV have interaction with age, TC, TG, HDL-C and LDL-C.