Long-term administration of atorvastatin had no effect on the occurrence and progression of spontaneous hypertensive intracerebral hemorrhage in mice

Abstract

Abstract Background Intracerebral hemorrhage (ICH) is a catastrophic disease with limited treatment options. Statins and low low-density lipoprotein cholesterol (LDL-C) levels have been reported to be associated with increased risk of ICH. Safety concerns of statins were raised as statins become the cornerstone of anti-atherosclerosis therapy. To date, the effect of statins on the incidence of ICH still remains a controversial topic. Purpose The aim of this study was to investigate the effect of atorvastatin on the occurrence and progression of hypertensive ICH in mice. Methods Male wild-type C57BL/6J mice, 13 months old, were randomly divided into atorvastatin (Ato, n=20) group and vehicle (Veh, n=20) group. The atorvastatin group and vehicle group were given atorvastatin (20 mg/kg) and same volume of 0.5% sodium carboxymethylcellulose by oral gavage for 8 weeks, separately. Angiotensin II (Ang II) and L-NAME were then used to induce hypertensive ICH. The time of stroke symptom onset was documented. Hemorrhage volumes were measured by spectrophotometric hemoglobin assay. Results After 8 weeks of atorvastatin or vehicle administration, serum LDL-C levels were significantly lower in the mice treated with atorvastatin than vehicle controls (0.705 vs. 1.008 mmol/L, P<0.001). The administration of atorvastatin did not show significant effects on the systolic blood pressure (SBP) levels when compared with the vehicle group (164 vs. 166 mmHg, P=0.497) after the induction of Ang II and L-NAME. Hemorrhage was observed in brain morphology, and was further verified by hematoxylin and eosin staining or MRI scans in mice that showed signs of stroke. During the 28-day experimental period, 75% (15/20) of mice in the atorvastatin group developed signs of ICH, and 70% (14/20) of mice in the vehicle group developed in the similar time window. The incidence of hypertensive ICH had no significant difference between atorvastatin and vehicle groups (Log-rank P=0.761). Hemorrhage volumes were also comparable between the two groups (1.462 vs. 1.392 uL, P=0.788). Conclusion Reducing serum LDL-C levels by long-term administration of atorvastatin had no effect on the occurrence and progression of spontaneous hypertensive ICH in middle-aged mice.