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Familial hypercholesterolemia (FH) is caused by mutations in various genes, including the LDLR, APOB and PSCK9 genes; however, the spectrum of these mutations in Russian individuals has not been fully investigated. In the present study, mutation screening was performed on the LDLR gene and other FH-associated genes in patients with definite or possible FH, using next-generation sequencing. In total, 59 unrelated patients were recruited and sorted into two separate groups depending on their age: Adult (n=31; median age, 49; age range, 23-70) and children/adolescent (n=28; median age, 11; age range, 2-21). FH-associated variants were identified in 18 adults and 25 children, demonstrating mutation detection rates of 58 and 89% for the adult and children/adolescent groups, respectively. In the adult group, 13 patients had FH-associated mutations in the LDLR gene, including two novel variants [NM_000527.4: c.433_434dupG p.(Val145Glyfs*35) and c.1186G>C p.(Gly396Arg)], 3 patients had APOB mutations and two had ABCG5/G8 mutations. In the children/adolescent group, 21 patients had FH-causing mutations in the LDLR gene, including five novel variants [NM_000527.4: c.325T>G p.(Cys109Gly), c.401G>C p.(Cys134Ser), c.616A>C p.(Ser206Arg), c.1684_1691delTGGCCCAA p.(Pro563Hisfs*14) and c.940+1_c.940+4delGTGA], and 2 patients had APOB mutations, as well as ABCG8 and LIPA mutations, being found in different patients. The present study reported seven novel LDLR variants considered to be pathogenic or likely pathogenic. Among them, four missense variants were located in the coding regions, which corresponded to functional protein domains, and two frameshifts were identified that produced truncated proteins. These variants were observed only once in different patients, whereas a splicing variant in intron 6 (c.940+1_c.940+4delGTGA) was detected in four unrelated individuals. Previously reported variants in the LDLR, APOB, ABCG5/8 and LIPA genes were observed in 33 patients. The LDLR p.(Gly592Glu) variant was detected in 6 patients, representing 10% of the FH cases reported in the present study, thus it may be a major variant present in the Russian population. In conclusion, the present study identified seven novel variants of the LDLR gene and broadens the spectrum of mutations in FH-related genes in the Russian Federation.

Tissue specific expression of genes encoding the cholesterol transporters ABCA1 and ABCG1 as well as genes encoding the most important transcriptional regulators of adipogenesis (LXRα, LXRβ, PPARγ and RORα) has been investigated in intraabdominal adipose tissue (IAT) samples from obese patients and patients without overweight. A direct correlation between the content of ABCA1 and ABCG1 proteins and the RORα protein level (r = 0.480, p < 0.05; r = 0.435, p < 0.05, respectively) suggests involvement of the transcription factor RORα in the regulation of ABCA1 and ABCG1 protein levels in IAT. ABCA1 and ABCG1 gene expression positively correlated with such obesity indicators as body mass index (BMI) (r = 0.522, p = 0.004; r = 0.594, p = 0.001, respectively) and waist circumference (r = 0.403, p = 0.033; r = 0.474, p = 0.013, respectively). The development of obesity is also associated with decreased IAT levels of RORα and LXRβ mRNA (p = 0.016 and p = 0.002, respectively). This suggest that the nuclear factor RORα can play a significant role in the regulation of cholesterol metabolism and control IAT expression of ABCA1 and ABCG1 genes, while the level of IAT LXRβ gene expression may be an important factor associated with the development of obesity.

Atherosclerosis is one of the most common causes of death worldwide. Epidemiology studies firmly established an inverse relationship between atherogenesis and distorted lipid metabolism, in particular, higher levels of total cholesterol, an accumulation of CH-laden macrophages (foam cells), and lower plasma levels of antiatherogenic high density lipoprotein (HDL). It is believed that the reverse cholesterol transport, a process that removes excess cholesterol from peripheral tissues/cells including macrophages to circulating HDL, is one of the main mechanisms responsible for anti-atherogenic properties of HDL. The key proteins of reverse cholesterol transport-ATP-binding cassette transporters A1 (ABCA1) and G1 (ABCG1)-mediate the cholesterol efflux from macrophages and prevent their transformation into foam cells. This review focuses on the role of ABC transporters A1 and G1 in the pathogenesis of atherosclerosis.

Nuclear receptors LXRα/β and PPARγ play an important role in the regulation of lipid metabolism and reverse cholesterol transport. However, the effect of the expression of LXRα/β and PPARγ genes in macrophages on the development of atherosclerosis remains poorly studied. We determined the levels of LXRα mRNA, LXRβ mRNA, and PPARγ mRNA by a real-time polymerase chain reaction in macrophages cultivated for 5 days with macrophage colony-stimulating factor (M-CSF). The levels of LXRβ mRNA and PPARγ mRNA were lower in patients with coronary artery stenosis than in the control group, p < 0.001. The groups did not differ in the content of LXRα mRNA (p = 0.17). We suggest that the level of expression of LXRβ and PPARγ genes in macrophages may be a significant factor associated with the development of atherosclerosis.

The antiatherogenic role of high-density lipoproteins (HDL) was demonstrated by numerous experimental, clinical and epidemiological studies. The mechanism underlying the antiatherogenic potential of HDL is based on their involvement in reverse cholesterol transport (RCT) from peripheral tissues into the liver. Transmembrane transporter ABCG1 is a key RCT protein. Its function is to remove cholesterol from cells and transfer it to HDL. The role of ABCG1 transporter in the development of atherosclerosis in humans remains unexplored. The goal of our study was to investigate the expression of ABCG1 gene in patients with atherosclerosis. Real-time PCR was applied to study ABCG1 mRNA content in leukocytes, monocytes, and macrophages activated with macrophage colony-stimulating factor (M-CSF) from patients with atherosclerosis and healthy people. The amount of ABCG1 protein in monocytes and macrophages of patients and healthy donors was assayed by immunoblotting. It was found that the level of ABCG1 mRNA (p < 0.001) and ABCG1 protein (p < 0.05) was lower in macrophages of patients with atherosclerosis. The level of ABCG1 mRNA in monocytes of patients with artery occlusion was lower than in patients with features of lesser stenosis and the control group (p < 0.05). No correlation was found between ABCG1 gene expression and total and HDL cholesterol levels in the blood plasma. It can be concluded that reduced ABCG1 gene expression in monocytes and macrophages may be critical for the atherosclerosis progression.

Nuclear receptors LXRα/β and PPARγ play an important role in lipid metabolism and reverse cholesterol transport. However, the influence of LXRα/β and PPARγ mRNA levels in macrophages on atherosclerosis remains unexplored. Using real time PCR, we determined LXRα mRNA, LXRβ mRNA and PPARγ mRNA levels in macrophages cultured for 5 days with macrophage colony-stimulating factor (M-CSF). Levels of LXRβ mRNA and PPARγ mRNA in patients with arterial stenosis were reduced when compared with the control group, p 0.001. LXRa gene mRNA level in macrophages was not changed in the study groups, (p = 0.17). Thus, our study shows that the LXRβ and PPARγ genes expression levels in macrophages may be significant factors associated with the development of atherosclerosis.

ABCA1 transporter is one of the key factors defining the level of antiatherogenic HDL in plasma. It is involved in cholesterol removal from peripheral tissues by reverse cholesterol transport. However, the influence of ABCA1 mRNA and ABCA1 protein levels in macrophages on atherosclerosis remains unexplored. Using real-time PCR, we determined the ABCA1 mRNA level in macrophages cultured for 5 days with macrophage colony-stimulating factor (M-CSF). The ABCA1 mRNA level in macrophages from patients with arterial stenosis was increased compared to the control group, p = 0.04. Western-blot assayed ABCA1 protein content in macrophages from patients was significantly lower than in the control group, p = 0.01. Our results suggest that ABCA1 mRNA and ABCA1 protein levels in macrophages may be important factors in the development of atherosclerosis.

Apolipoprotein A-I is a key structure protein of antiatherogenic high density lipoproteins (HDL). The aim of the study was to investigate the relationship between (-75)G/A and 83C/T polymorphic variants of apolipoprotein A-I gene (APOA1) and the plasma lipid profile in the population of Saint-Petersburg. Allele T83 of APOA1 gene was found to be associated with the reduced risk of atherosclerosis development among Saint-Petersburg inhabitants. The study demonstrates that allele T83 of APOA1 gene is associated with higher plasma HDL cholesterol levels (p

Apoprotein A-1 is a major protein in antiaterogenic high density lipoproteins and it is one of key proteins regulating reverse cholesterol transport. In this study we have investigated association of APOA1 gene polymorphism with atherosclerosis development among Saint-Petersburg population. Allelic frequencies of polimorphic variants (-75)G/A and 83C/T of APOA1 gene were determined in the group of patients with angiographically proven aterosclerosis and in control group. Allele 83T of the APOA1 gene is associated with lower risk of atherosclerosis development among Saint-Petersburg population.

Amodiaquine (AQ) and tebuquine are 4-aminoquinoline antimalarials with Mannich base side chain and are highly effective against chloroquine (CQ)-resistant strains of Plasmodium falciparum. Clinical use of AQ has been severely restricted due to hepatoxicity and agranulocytosis side effects associated with its long term use. Lysosomal accumulation and bioactivation to generate reactive quinoneimine metabolite are implicated to be the cause of the observed AQ toxicities. To avoid the quinoneimine formation and thus the toxicity, a series of isotebuquine analogues and their Nomega-oxides with hydroxy group meta to the amino rather than in para position of the aniline moiety were prepared. The new Mannich bases are highly active against both CQ-sensitive (D6) and -resistant (W2 and TM91C235) clones of P. falciparum with IC50 in the range of 0.3-120 ng/mL. New compounds are1000-fold less toxic (IC50 = 0.7-6 microg/mL) to mouse macrophage cell line than to parasite cell lines. Mono-Mannich bases are more active than bis-Mannich bases. Mono-Mannich base 1a (IC50 = 0.3 ng/mL) is 20-fold more active than the corresponding trifluoromethyl analogue 1b. No appreciable difference in either toxicity or efficacy were observed between the new Mannich bases (m-hydroxyaniline derivatives) 1a or 2a and the corresponding p-hydroxyaniline derivatives.

We evaluated association of BP stress-reactivity on the model of cardiac defense response in 45-70-year-old men with variable number of tandem repeat polymorphism in genes encoding dopamine transporter protein (DAT1) and serotonin transporter protein (5-HTTLPR). It was found that individuals carrying long allele variant (l) of DAT1 gene (l/l: allele l homozygotes) in the genotype in comparison with short variant (s) carriers (heterozygous genotype l/s) demonstrate hyperreactive profi les of cardiovascular stress reactivity characterized by a signifi cant increase in the amplitude and duration of long-latency BP components in cardiac defensive response.

Two local macroalgal species (Undaria pinnatifida and Gracilaria vermiculophylla) were tested in laboratory experiments to determine their nutrient uptake potential and their physiological response to waste water effluents from a mariculture project on bivalve mollusks (mussels). No negative effects on the growth and photosynthesis rates of the algae were detected. High nutrient uptake rates and high nutrient removal efficiency were measured in both tested species. We propose that U. pinnatifida be introduced into IMTA systems during the cold-water season to remove nutrients from cultured animals. The culture of this species can be alternated with that of G. vermiculophylla during warm-water season in order to provide a longer biofiltration period.