MicroRNA-20a-5p Downregulation by Atorvastatin: A Potential Mechanism Involved in Lipid-Lowering Therapy.

The treatment of hypercholesterolemia is mainly based on statins. However, the response to pharmacological therapy shows high inter-individual variability, resulting in variable effects in both lipid lowering and risk reduction. Thus, a better understanding of the lipid-lowering mechanisms and response variability at the molecular level is required. Previously, we demonstrated a deregulation of the microRNA expression profile in HepG2 cells treated for 24 h with atorvastatin, using a microarray platform. In the present study, we evaluated the expression of hsa-miR-17-5p, hsa-miR-20a-5p and hsa-miR-106a-5p in hypercholesterolemic patients before and after atorvastatin treatment and in HepG2 cells treated for 24 h with atorvastatin The miRNA hsa-mir-20a-5p was repressed after atorvastatin treatment in hypercholesteremic subjects and in HepG2 cells in culture. Repression of hsa-mir-20a-5p increased LDLR gene and protein expression in HepG2 cells, while hsa-mir-20a-5p overexpression reduced LDLR gene and protein expression.

SLCO1B1 c.388A>G Polymorphism Is Associated with HDL-C Levels in Response to Atorvastatin in Chilean Individuals.

The use of statins as the preferred lipid-lowering therapy has clearly demonstrated its efficacy in the treatment of hypercholesterolemia, reducing also the risk of coronary events and cardiovascular disease mortality. In this study, we assessed single nucleotide polymorphisms (SNPs) in the SLCO1B1 gene and their effect on atorvastatin response. We included 129 Chilean hypercholesterolemic patients undergoing 10 mg/day of atorvastatin therapy during 4 weeks. Lipid profile was determined before and after drug administration. Genotyping of SLCO1B1 rs4149056 (c.521T>C) SNP was performed with allele-specific polymerase chain reaction, whilst polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for genotyping the SLCO1B1 rs2306283 (c.388A>G) variant. After statin therapy, concentrations of TC, LDL-C and TG had a decrease from baseline (p < 0.05). Also, HDL-C levels increased (p < 0.05). Minor allele frequencies for the rs2306283 and rs4149056 variants were 0.547 and 0.136, respectively. LDL-C response to atorvastatin was not associated with the SLCO1B1 rs4149056 nor the rs2306283 polymorphisms (p > 0.05). However, the latter SNP was associated with HDL-C variability after atorvastatin medication (p = 0.02). This study indicates that LDL-C reduction following atorvastatin therapy is not influenced by the SNPs evaluated. In addition, the polymorphism rs2306283 at the SLCO1B1 gene determines greater HDL-C concentrations in response to atorvastatin medication in Chilean hypercholesterolemic subjects.

Cholesterol-Related lncRNAs as Response Predictors of Atorvastatin Treatment in Chilean Hypercholesterolemic Patients: A Pilot Study.

Statins are currently the treatment of choice for hypercholesterolemia. However, wide interindividual variability has been observed in the response to treatment. Recent studies have reported the role of lncRNAs in the metabolism of lipids; nevertheless, there are few studies to date that show their role in the response to treatment with statins. Thus, the aim of this study was to assess the levels of expression of three lncRNAs (RP1-13D10.2; MANTIS; lncHR1) associated with genes involved in cholesterol homeostasis in leukocyte cells of hypercholesterolemic patients after treatment with atorvastatin and compare them with levels in subjects with normal cholesterol levels. A secondary aim was to assess the levels of expression in monocytic THP-1 cells differentiated to macrophages. The study included 20 subjects with normal cholesterol (NC) levels and 20 individuals with hypercholesterolemia (HC). The HC patients were treated with atorvastatin (20 mg/day/4 weeks). THP-1 cells were differentiated to macrophages with PMA and treated with different doses of atorvastatin for 24 h. Expression of lncRNAs was determined by RT-qPCR. The lncRNAs RP1-13D10.2 (p < 0.0001), MANTIS (p = 0.0013) and lncHR1 (p < 0.0001) presented increased expression in HC subjects compared with NC subjects. Furthermore, atorvastatin had a negative regulatory effect on the expression of lncHR1 (p < 0.0001) in HC subjects after treatment. In vitro, all the lncRNAs showed significant differences in expression after atorvastatin treatment. Our findings show that the lncRNAs tested present differential expression in HC patients and play a role in the variability reported in the response to atorvastatin treatment. Further research is needed to clarify the biological impact of these lncRNAs on cholesterol homeostasis and treatment with statins.

MicroRNA-33b is a Potential Non-Invasive Biomarker for Response to Atorvastatin Treatment in Chilean Subjects With Hypercholesterolemia: A Pilot Study.

Evidence accumulated so far indicates that circulating levels of microRNAs (miRNAs) are associated with several pathologies. Therefore, differential expression of extracellular miRNAs exhibits promising potential for screening and diagnosis purposes. We evaluated plasma miRNAs in response to the lipid-lowering drug atorvastatin in patients with hypercholesterolemia (HC) and controls. METHODS: We selected miRNAs based on previous data reported by our group and also by employing bioinformatics tools to identify 10 miRNAs related to cholesterol metabolism and statin response genes. Following miRNA identification, we determined plasma levels of miRNA-17-5p, miRNA-30c-5p, miRNA-24-3p, miRNA-33a-5p, miRNA-33b-5p, miRNA-29a-3p, miRNA-29b-3p, miRNA-454-3p, miRNA-590-3p and miRNA-27a-3p in 20 HC patients before and after 1 month of 20 mg/day atorvastatin treatment, evaluating the same miRNA set in a group of 20 healthy subjects, and employing qRT-PCR to determine differential miRNAs expression. RESULTS: HC individuals showed significant overexpression of miRNA-30c-5p and miRNA-29b-3p vs. NL (p = 0.0008 and p = 0.0001, respectively). Once cholesterol-lowering treatment was concluded, HC individuals showed a substantial increase of three extracellular miRNAs (miRNA-24-3p, miRNA-590, and miRNA-33b-5p), the latter elevated more than 37-fold (p = 0.0082). CONCLUSION: Data suggest that circulating miRNA-30c-5p and miRNA-29b-3p are associated with hypercholesterolemia. Also, atorvastatin induces a strong elevation of miRNA-33b-5p levels in HC individuals, which could indicate an important function that this miRNA may exert upon atorvastatin therapy. Additional studies are needed to clarify the role of this particular miRNA in statin treatment.

Atorvastatin Increases the Expression of Long Non-Coding RNAs ARSR and CHROME in Hypercholesterolemic Patients: A Pilot Study.

Atorvastatin is extensively used to treat hypercholesterolemia. However, the wide interindividual variability observed in response to this drug still needs further elucidation. Nowadays, the biology of long non-coding RNAs (lncRNAs) is better understood, and some of these molecules have been related to cholesterol metabolism. Therefore, they could provide additional information on variability in response to statins. The objective of this research was to evaluate the effect of atorvastatin on three lncRNAs (lncRNA ARSR: Activated in renal cell carcinoma (RCC) with sunitinib resistance, ENST00000424980; lncRNA LASER: lipid associated single nucleotide polymorphism locus, ENSG00000237937; and lncRNA CHROME: cholesterol homeostasis regulator of miRNA expression, ENSG00000223960) associated with genes involved in cholesterol metabolism as predictors of lipid-lowering therapy performance. Twenty hypercholesterolemic patients were treated for four weeks with atorvastatin (20 mg/day). The lipid profile was determined before and after drug administration using conventional assays. The expression of lncRNAs was assessed in peripheral blood samples by RT-qPCR. As expected, atorvastatin improved the lipid profile, decreasing total cholesterol, LDL-C, and the TC/HDL-C ratio (p < 0.0001) while increasing the expression of lncRNAs ARSR and CHROME (p < 0.0001) upon completion of treatment. LASER did not show significant differences among the groups (p = 0.50). Our results indicate that atorvastatin modulates the expression of cholesterol-related lncRNAs differentially, suggesting that these molecules play a role in the variability of response to this drug; however, additional studies are needed to disclose the implication of this differential regulation on statin response.

Gender-Specific Association Between ABCC2 -24C>T SNP and Reduction in Triglycerides in Chilean Patients Treated With Atorvastatin.

Statins are the first-line therapy prescribed to lower plasma cholesterol levels. Although being safe and showing several beneficial cholesterol-independent pleiotropic effects, a significant variability regarding statin's therapeutic goals has been abundantly documented, but less understood. We aimed to investigate the influence of the ABCC2 -24C>T single nucleotide polymorphism on Chilean hypercholesterolaemic individuals treated for 4 weeks with 10 mg/day atorvastatin. A total of 127 individuals medicated with atorvastatin 10 mg/day/4 weeks were included. Lipid profiles were determined before and after drug administration by conventional assays. Genotyping of the ABCC2 rs717620 SNP (-24C>T) was performed with TaqMan® Drug Metabolism Genotyping Assays. As expected, atorvastatin reduced TC, LDL-C and TG concentrations (p < 0.05). Also, HDL-C levels were increased (p < 0.05). Minor allele frequency for the rs717620 was 0.232. Overall, atorvastatin response was not associated with the ABCC2 rs717620 SNP (p > 0.05). Nonetheless, in male individuals carrying the -24T allele, we observed an attenuated reduction in both TG values and the TG/HDL-C ratio after 10 mg/day atorvastatin. This study indicates that TG levels and the TG/HDL-C ratio are affected by the rs717620 SNP in Chilean males but not female individuals after atorvastatin treatment.

CYP2C19⁎2 Polymorphism in Chilean Patients with In-Stent Restenosis Development and Controls.

Clopidogrel is an antiplatelet drug especially used in patients undergoing percutaneous coronary interventions (PCI). Polymorphisms within CYP2C19 can result in important interindividual variations regarding therapeutic efficacy. Therefore, we aimed to evaluate the impact of the CYP2C19⁎2 variant (rs4244285) on in-stent restenosis occurrence in Chilean patients who underwent PCI and received clopidogrel. A total of 77 cases with stenosis >50% in the angioplasty site (62.75 ± 9.8 years, 80.5% males) and 86 controls (65.45 ± 9.8 years, 72.1% males) were studied. The polymorphism was genotyped using TaqMan® Drug Metabolism Genotyping Assays. Overall, CYP2C19⁎2 allele frequency was 8.3%. Diabetes, chronic lesions, and bare metal stents (BMS) were observed more often in cases than in controls (p = 0.05, p = 0.04, and p = 0.02, resp.). Genotypic frequencies did not differ significantly between the groups (p = 0.15). Nonetheless, the mutated allele was observed in a greater proportion in patients without in-stent restenosis (p = 0.055). There was no significant association between the rs4244285 variant and the occurrence of in-stent restenosis after PCI (OR = 0.44; 95% CI: 0.19 to 1.04; p = 0.06). In summary, no association was identified between the CYP2C19⁎2 variant and the development of coronary in-stent restenosis.