Ataei Sarina, Ganjali Shiva, Banach Maciej, Karimi Ehsan, Sahebkar Amirhossein
Department of Biology, Mashhad Branch, Islamic Azad University, Mashhad, Iran.
Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Arch Med Sci. 2023 Jan 13;19(1):203-208. doi: 10.5114/aoms/152000. eCollection 2023.
MicroRNAs (miRNAs) are a class of gene expression epigenetic regulators that play roles in regulating genes involved in cholesterol homeostasis, including low-density lipoprotein receptor (LDLR) and PCSK9; therefore, miRNAs have been suggested as potential therapeutic targets for treating cardiometabolic disorders. Thus, the present study aimed to assess the effect of immunotherapy with the PCSK9 peptide vaccine on the hepatic expression levels of microRNAs associated with the LDLR pathway, including miRNA-27a, miRNA-30c, and miRNA-191, in normal vaccinated mice.
PCSK9 immunogenic peptide and 0.4% alum adjuvant were mixed at a 1 : 1 ratio and used as a vaccine formulation. Male albino mice were randomly assigned to the vaccine or control group. Mice in the vaccine group were injected four times at two-week intervals with a PCSK9 peptide vaccine, and mice in the control group were injected with phosphate-buffered saline (PBS). Animal livers were sampled 2 weeks after the last injection to assess miRNA expression levels. The hepatic expression levels of miRNA-27a, miRNA-30c, and miRNA-191 were evaluated by SYBR Green real-time PCR, quantified by a comparative (2 ) method (fold change (FC)) and normalized to U6 small nuclear RNA (U6snRNA) expression as an internal control.
The hepatic expression level of miRNA-27a was significantly lower in mice following immunotherapy with the PCSK9 peptide vaccine compared to the control group (FC: 0.731 ±0.1, = 0.027). Also, there was a borderline significantly lower hepatic expression level of miRNA-30c in the vaccinated group compared to the control (FC: 0.569 ±0.1, = 0.078). However, no significant differences were found in the hepatic expression level of miRNA-191 between the two studied groups (FC: 0.852 ±0.1, = 0.343).
According to the findings, the PCSK9 peptide vaccine could effectively reduce the hepatic expression level of miRNA-27a and may be helpful in the management of LDL-C level and atherosclerosis, which may be mediated through the LDLR pathway.
微小RNA（miRNA）是一类基因表达表观遗传调节因子，在调节参与胆固醇稳态的基因（包括低密度脂蛋白受体（LDLR）和前蛋白转化酶枯草溶菌素9（PCSK9））中发挥作用；因此，miRNA被认为是治疗心脏代谢紊乱的潜在治疗靶点。因此，本研究旨在评估PCSK9肽疫苗免疫疗法对正常接种疫苗小鼠中与LDLR途径相关的微小RNA（包括miRNA-27a、miRNA-30c和miRNA-191）肝脏表达水平的影响。
将PCSK9免疫原性肽与0.4%明矾佐剂按1:1比例混合，用作疫苗制剂。将雄性白化小鼠随机分为疫苗组或对照组。疫苗组小鼠每隔两周注射四次PCSK肽疫苗，对照组小鼠注射磷酸盐缓冲盐水（PBS）。在最后一次注射后2周采集动物肝脏样本，以评估miRNA表达水平。通过SYBR Green实时PCR评估miRNA-27a、miRNA-30c和miRNA-191的肝脏表达水平，采用比较（2−ΔΔCt）方法进行定量（倍数变化（FC）），并将其标准化为U6小核RNA（U6snRNA）表达作为内参。
与对照组相比，PCSK9肽疫苗免疫治疗后的小鼠肝脏中miRNA-27a的表达水平显著降低（FC：0.731±0.1，P = 0.027）。此外，与对照组相比，接种组肝脏中miRNA-30c的表达水平有边缘性显著降低（FC：0.569±0.1，P = 0.078）。然而，在两个研究组之间，miRNA-191的肝脏表达水平未发现显著差异（FC：0.852±0.1，P = 0.343）。
根据研究结果，PCSK9肽疫苗可有效降低miRNA-27a的肝脏表达水平，可能有助于管理低密度脂蛋白胆固醇（LDL-C）水平和动脉粥样硬化，这可能是通过LDLR途径介导的。
