Comparing common doses (double-dose vs usual-dose) of atorvastatin for preventing contrast-induced acute kidney injury and mortality after coronary angiography

Loss of renal tubular G9a benefits acute kidney injury by lowering focal lipid accumulation via CES1

Surgery-induced renal ischemia and reperfusion (I/R) injury and nephrotoxic drugs like cisplatin can cause acute kidney injury (AKI), for which there is no effective therapy. Lipid accumulation is evident following AKI in renal tubules although the mechanisms and pathological effects are unclear. Here, we report that Ehmt2-encoded histone methyltransferase G9a is upregulated in patients and mouse kidneys after AKI. Renal tubular specific knockout of G9a (Ehmt2Ksp ) or pharmacological inhibition of G9a alleviates lipid accumulation associated with AKI. Mechanistically, G9a suppresses transcription of the lipolytic enzyme Ces1; moreover, G9a and farnesoid X receptor (FXR) competitively bind to the same promoter regions of Ces1. Ces1 is consistently observed to be downregulated in the kidney of AKI patients. Pharmacological inhibition of Ces1 increases lipid accumulation, exacerbates renal I/R-injury and eliminates the beneficial effects on AKI observed in Ehmt2Ksp mice. Furthermore, lipid-lowering atorvastatin and an FXR agonist alleviate AKI by activating Ces1 and reducing renal lipid accumulation. Together, our results reveal a G9a/FXR-Ces1 axis that affects the AKI outcome via regulating renal lipid accumulation.

The preventive effects of different doses of atorvastatin on contrast-induced acute kidney injury after CT perfusion

Background

Contrast‐induced acute kidney injury (CI‐AKI) is a severe complication among patients receiving intravascular contrast media. The purpose of this study was to investigate the preventive effects of pretreatment of atorvastatin at intensive doses on CI‐AKI after computed tomography (CT) perfusion.

Methods

The levels of serum creatinine (SCR), blood urea nitrogen (BUN), Cystatin C (CysC), estimated glomerular filtration rate (eGFR), high‐sensitivity C‐reactive protein (hs‐CRP), and interleukin‐6 (IL‐6) in patients were compared between the observation group receiving 40 mg/kg atorvastatin and the control group receiving 20 mg/kg atorvastatin before and 72 h after CT examination. In addition, the incidence of CI‐AKI was recorded.

Results

Compared with the control group, the incidence of renal injury in the observation group was significantly reduced, from 8% to 2% (χ² = 6.62, p = 0.010). In addition, there was no notable difference in the levels of Scr, BUN, CysC, hs‐CRP, and IL‐6 before CT examination between two groups (p > 0.05). The levels of SCR, BUN, CysC, hs‐CRP, and IL‐6 were increased, while the levels of eGFR were decreased in the control group at 72 h after CT examination (p < 0.05). At 72 h after CT enhancement, the levels of BUN, CysC, and hs‐CRP were prominently increased in the observation group (p < 0.05), while SCR, eGFR, and IL‐6 did not change (p > 0.05). Compared with the control group, the levels of SCR, BUN, CysC, eGFR, hs‐CRP, and IL‐6 in the observation group were significantly decreased at 72 h after CT examination (p < 0.05).

Conclusion

Intensive dose of atorvastatin pretreatment can prevent CI‐AKI undergoing CT perfusion through lowering inflammation as well as renal function indexes SCR, CysC, BUN, and eGFR.

Comparison of the preventive efficacy of rosuvastatin versus atorvastatin in post-contrast acute kidney injury in patients with ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention

Statins have been shown to reduce the risk of post-contrast acute kidney injury (PC-AKI) in patients undergoing percutaneous coronary intervention (PCI). However, the preventive effect of rosuvastatin versus atorvastatin on PC-AKI in patients with ST-segment elevation myocardial infarction (STEMI) undergoing PCI remains unclear. Patients with STEMI undergoing PCI between January 2010 and May 2016 were consecutively enrolled. A total of 1300 included patients were divided into two groups according to the statin type (atorvastatin: n = 1040; rosuvastatin: n = 260). The primary endpoint was PC-AKI defined as an absolute increase of ≥ 0.5 mg/dL in the level of serum creatinine or an increase of ≥ 25 % over baseline within 48-72 h after contrast media exposure. In total, 245 (18.8 %) patients developed PC-AKI. The atorvastatin and rosuvastatin groups had similar rates of PC-AKI (19.1 % vs. 17.7 %, p = 0.595), in-hospital mortality (4.1 % vs. 3.8 %, p = 0.833), and major adverse clinical events (MACE). Multivariate logistic regression analysis revealed that rosuvastatin treatment had an effect similar to atorvastatin regarding PC-AKI (odds ratio [OR] = 0.97, 95 % confidence interval [CI], 0.66-1.43, p = 0.874). Propensity score analyses and subgroup analysis demonstrated similar results for PC-AKI. Kaplan-Meier survival curves and Cox proportional regression showed that the atorvastatin and rosuvastatin groups had no differences regarding follow-up mortality. Rosuvastatin exerted a similar preventive effect against PC-AKI and showed similar levels of in-hospital and follow-up all-cause mortality and in-hospital MACE compared with atorvastatin in patients with STEMI undergoing PCI.

Simvastatin Attenuates Cardiac Fibrosis via Regulation of Cardiomyocyte-Derived Exosome Secretion

Exosome-mediated communication within the cardiac microenvironment is associated with cardiac fibrosis. Simvastatin (SIM), a potent statin, protects against cardiac fibrosis, but its mechanism of action is unclear. We investigated the inhibitory effects and underlying mechanism of simvastatin in cardiac fibrosis, by regulating exosome-mediated communication. Male Sprague-Dawley rats were treated with angiotensin (Ang) II alone, or with SIM for 28 d. Cardiac fibrosis, expressions of fibrosis-associated proteins and mRNAs, and collagen fiber arrangement and deposition were examined. Protein expressions in exosomes isolated from Ang II-treated cardiomyocytes (CMs) were evaluated using nano-ultra-performance liquid chromatographic system, combined with tandem mass spectrometry. Transformation of fibroblasts to myofibroblasts was evaluated using scanning electron and confocal microscopy, and migration assays. Our results showed that SIM attenuated in vivo expression of collagen and collagen-associated protein, as well as collagen deposition, and cardiac fibrosis. The statin also upregulated decorin and downregulated periostin in CM-derived exosomes. Furthermore, it suppressed Ang II-induced transformation of fibroblast to myofibroblast, as well as fibroblast migration. Exosome-mediated cell-cell communication within the cardiac tissue critically regulated cardiac fibrosis. Specifically, SIM regulated the release of CM exosomes, and attenuated Ang II-induced cardiac fibrosis, highlighting its potential as a novel therapy for cardiac fibrosis.