Clinical characteristics and in-hospital outcome in percutaneous coronary interventions with ST elevation myocardial infarction patients developing acute kidney injury

Lipoprotein (a) variability is associated with mean follow-up C-reactive protein in patients with coronary artery disease following percutaneous coronary intervention

BACKGROUND

Increased lipoprotein (a) [lp (a)] has proinflammatory effects, which increase the risk of coronary artery disease. However, the association between lp (a) variability and follow-up C-reactive protein (CRP) level in patients undergoing percutaneous coronary intervention (PCI) has not been investigated.

AIM

To explore the association between lp (a) variability and mean CRP levels within the 1^st year post-PCI.

METHODS

Results of lp (a) and CRP measurements from at least three follow-up visits of patients who had received PCI were retrospectively analyzed. Standard deviation (SD), coefficient of variation (CV), and variability independent of the mean (VIM) are presented for the variability for lp (a) and linear regression analysis was conducted to correlate lp (a) variability and mean follow-up CRP level. The relationship of lp (a) variability and inflammation status was analyzed by restricted cubic spline analysis. Finally, exploratory analysis was performed to test the consistency of results in different populations.

RESULTS

A total of 2712 patients were enrolled. Patients with higher variability of lp (a) had a higher level of mean follow-up CRP (P < 0.001). lp (a) variability was positively correlated with the mean follow-up CRP (SD: β = 0.023, P < 0.001; CV: β = 0.929, P < 0.001; VIM: β = 1.648, P < 0.001) by multivariable linear regression analysis. Exploratory analysis showed that the positive association remained consistent in most subpopulations.

CONCLUSION

Lp (a) variability correlated with mean follow-up CRP level and high variability could be considered an independent risk factor for increased post-PCI CRP level.

Klotho overexpression suppresses apoptosis by regulating the Hsp70/Akt/Bad pathway in H9c2(2-1) cells

Early reperfusion is the most effective and important treatment for acute myocardial infarction. However, reperfusion therapy often leads to a certain degree of myocardial damage. The aim of the present study was to identify the role of klotho, and the molecular mechanism underlying its effects, in myocardial damage using a model of myocardial hypoxia injury. Hypoxia/reoxygenation (H/R) was used to mimic ischemia/reperfusion (I/R) injury in vitro. The expression and distribution of klotho in H9c2(2-1) cells was observed by fluorogenic scanning, and the apoptotic rate was determined by Annexin V-FITC/propidium iodide dual staining. Cell viability was determined by MTT assay, and caspase-3, cleaved caspase-3, Bcl-2, Bax, heat shock protein (Hsp) 70 and Akt levels were assessed by western blotting. A lactate dehydrogenase test was performed to determine the degree of H9c2(2-1) cell damage. The results revealed that klotho was primarily located in the cytoplasm of H9c2(2-1) cells. Klotho overexpression markedly suppressed H/R-induced H9c2(2-1) cell apoptosis. Furthermore, cell viability increased, and injury decreased in response to klotho. Klotho also suppressed the activation of caspase-3, upregulated Bcl2 and decreased Bax levels following H/R injury, as well as alleviating H/R injury by upregulating the expression of Hsp70 and increasing the levels of phosphorylated (p-)Akt and Bad. In conclusion, these results indicate that klotho suppressed H/R-induced H9c2(2-1) cell apoptosis by regulating the levels of Hsp70, p-Akt and p-Bad, which suggest that klotho could be a novel agent for the treatment of coronary disease.