Pharmacogenomics of response to statin treatment and susceptibility to statin-induced adverse drug reactions in Asians: a scoping review

Background

Statins are the most widely used lipid-lowering agents for patients with hyperlipidemia. However, interindividual variations in efficacy and risk of adverse drug reactions to statin treatment have been widely reported. Ethnicity is well known to be one of the contributing factors to this variation, particularly among Asians.

Objectives

To identify genetic variants associated with statin treatment responses among Asian populations with a focus on four commonly prescribed statins: atorvastatin, rosuvastatin, simvastatin, and pravastatin.

Methods

A literature search was conducted in Medline and Embase databases. Studies published from 2008 to 2021 were included. The title and abstract of each article were screened by two reviewers and verified by another two reviewers. Data charted include information on authors, year of study, study population, statin studied, gene studied, study findings, and data of significant statistical value.

Results

A total of 35 articles were included from the 1,939 original studies related to treatment efficacy and 5 articles out of the 284 original studies related to adverse effects. Genetic variants in transmembrane transporters, cytochrome P450 isoenzymes, and apolipoproteins are the most extensively studied among Asian populations, with a main focus on ethnic Chinese. However, Asia consists of genetically different populations, and the results of this review indicated that there is a paucity of studies on other ethnic groups within Asia.

Conclusions

Considering the ethnicity of patients could provide a potential value to personalized medicine in statin therapy.

Leptin promoter variant G2548A is associated with serum leptin and HDL-C levels in a case control observational study in association with obesity in a Pakistani cohort

Leptin is a protein hormone synthesized by adipocytes and is involved in the regulation of food intake and energy expenditure. We hypothesized that any change in the promoter sequence can affect the expression of the gene and hence leptin protein levels in the serum. The aim of the current study was to investigate the relationship of such a promoter variant of the leptin gene, G-2548A polymorphism, with obesity and its effect on various anthropometric and metabolic parameters in a Pakistani cohort consisting of 250 obese and 225 non-obese control subjects. Body weight, height, waist circumference (WC), hip circumference (HC) and blood pressure (BP) were measured by standard methods and levels of fasting blood glucose (FBG), total cholesterol, triglycerides, HDLC, LDLC, and leptin were determined. Genotyping was done by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results showed that the LEP G-2548A polymorphism showed significant association with obesity in Pakistan. In addition, the polymorphism showed association with weight, height, BMI, WC, HDLC and serum leptin levels. The findings suggest that the leptin promoter G-2548A variant may play its part in the progression to obesity by not only affecting the body's fat distribution but also by changing the serum leptin and HDLC levels.

Leptin and leptin-receptor polymorphisms in fertile and infertile men

The association of leptin (LEP) -2548G/A and/or leptin receptor (LEPR) Gln223Arg polymorphisms with male infertility and plasma FSH, LH, and testosterone (T) levels was examined. The genotypes and allele frequency distributions of LEP -2548G/A and LEPR Gln223Arg polymorphisms were investigated in 150 fertile and 150 infertile men by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Also, plasma levels of FSH, LH, and T were measured using commercial ELISA kits. Frequencies of AA, AG and GG genotypes of LEP-2548G/A polymorphism were statistically different in fertile and infertile men (p=0.012). The AG genotype showed a protective effect which could decrease risk of male infertility about 3 fold (p = 0.004). We did not observe any differences in frequencies of LEPR Gln223Arg alleles and genotypes between groups (p > 0.05). Sperm counts from infertile men with the AG and GG genotypes of the LEP polymorphism were significantly higher than AA genotype (p<0.05). Moreover, infertile men who carried the RR genotype of LEPR showed a statistically higher percentage of sperm with progressive motility than individuals with other genotypes (p = 0.004). There was no correlation between different combinations of LEP and LEPR genotypes and LH, FSH, and T levels (p > 0.05). Our study suggests that the LEP -2548G/A polymorphism may play a role in male fertility and the AG genotype may have a protective effect through increasing sperm counts. The distribution of genotypes of LEP -2548G/A polymorphism are different in fertile and infertile males and may be a useful tool in evaluation of male infertility.

ABBREVIATIONS

LEP: leptin; LEPR: leptin receptor; T: testosterone; FSH: follicle-stimulating hormone; LH: luteinizing hormone.