Genetic heterogeneity of familial hypercholesterolaemia in two populations from two different countries.

BACKGROUND: Familial hypercholesterolemia (FH) is a genetically determined monogenic disorder of predominantly autosomal dominant inheritance. A number of studies on differences in the genetic profile of patients with FH have demonstrated the importance of a more substantive evaluation of genetic features. The aim of this study was to evaluate the genetic profile of patients with clinical FH among Italian and Russian patients. METHODS: We included 144 Italian and 79 Russian FH patients; clinical diagnosis was based on the same criteria. Patients were divided in: positive to genetic test (one causative variant), inconclusive (only variants of uncertain clinical significance [VUS]), and negative (with likely benign/benign variants, heterozygous variants in LDLRAP1 gene, or without causative variants). RESULTS: The genetic test was positive in 76.4 % of the Italian patients and in 49.4 % of the Russian patients. The presence of VUS alone was detected in 7.6 % and in 19.0 % (p < 0.001), respectively. Among patients with positive genetic diagnosis, pre-treatment LDL-C levels were higher in the Russian cohort (353.5 ± 111.3 vs. 302.7 ± 52.1 mg/dL, p = 0.009), as well as the percentage of treated patients (53.8 % vs. 14.5 %, p < 0.001) and the prevalence of premature coronary heart disease (12.8 % vs. 3.6 %, p = 0.039). Among patients carrying only VUS, mean pre-treatment LDL-C levels were similar between the cohorts (299.5 ± 68.1 vs. 295.3 ± 46.8 mg/dL, p = 0.863). Among pathogenic/likely pathogenic variants and VUS, only 5 % and 4 % was shared between the two cohorts, respectively. CONCLUSION: The genetic background of patients clinically diagnosed with FH in two different countries is characterized by high variability.

The zebrafish model system for dyslipidemia and atherosclerosis research: Focus on environmental/exposome factors and genetic mechanisms.

Dyslipidemias and atherosclerosis play a pivotal role in cardiovascular risk and disease. Although some pathophysiological mechanisms underlying these conditions have been unveiled, several knowledge gaps still remain. Experimental models, both in vitro and in vivo, have been instrumental to our better understanding of such complex processes. The latter have often been based on rodent species, either wild-type or, in several instances, genetically modified. In this context, the zebrafish may represent an additional very useful in vivo experimental model for dyslipidemia and atherosclerosis. Interestingly, the lipid metabolism of zebrafish shares several features with that present in humans, recapitulating some molecular features and pathophysiological aspects in a better way than that of rodents. The zebrafish model may be of help to address questions related to exposome factors as well as to genetic features, aiming to dissect selected aspects of the more complex scenario observed in humans. Indeed, exposome-related dyslipidemia/atherosclerosis research in zebrafish may target different scientific questions, related to nutrition, microbiota, temperature, light exposure at the larval stage, exposure to chemicals and epigenetic consequences of such external factors. Addressing genetic features related to dyslipidemia/atherosclerosis using the zebrafish model is already a reality and active research is now ongoing in this promising area. Novel technologies (gene and genome editing) may help to identify new candidate genes involved in dyslipidemia and dyslipidemia-related diseases. Based on these considerations, the zebrafish experimental model appears highly suitable for the study of exposome factors, genes and molecules involved in the development of atherosclerosis-related disease as well as for the validation of novel potential treatment options.

Prevalence and relationship between metabolic syndrome and risk of cardiovascular disease: Evidence from two population-based studies.

BACKGROUND AND AIM: The metabolic syndrome (MetS) has become one of the most important clinical issues in the cardiovascular field for this decade because of the marked increase in cardiovascular (CV) risk associated with a clustering of risk factors. The aim of the current study was to evaluate the relationship between MetS and its components and cardiovascular disease (CVD). METHODS: This population-based cross-sectional study was based on data from two studies carried out in Russia (ESSE-RF) and Italy (PLIC). One sample from each cohort was selected, matching individuals by sex and age. A comparison between samples of MetS components distribution and CV risk, according to SCORE chart, has been conducted. RESULTS: A total of 609 individuals (mean [SD] age 55 [8] years, about 39% males) for each cohort were selected. Almost half of PLIC cohort participants belonged to the moderate CV risk group (47% vs 27%), while in ESSE-RF cohort a relatively higher prevalence of individuals classified in the high and very high risk group was observed (19% vs 11%, 21% vs 6%, respectively). Overall, 43% of ESSE-RF participants were diagnosed with MetS, compared with the 27% of PLIC members (the difference in prevalence becomes 37% vs 21%, considering a more conservative cut-off for waist circumference). Both cohorts showed a trend towards the increase of MetS components moving from the lowest to the highest CV risk class, with a high prevalence of patients with four or five MetS determinants allocated in the high/very high CV risk group. CONCLUSIONS: Developing effective public health strategies for the prevention, detection and treatment of MetS should be an urgent priority to reduce the burden of CVD, not only in subjects at high/very high CV risk, but also in those characterized by a lower risk, as even rare CV events that come from low risk group bring a tangible burden to healthcare systems.