Q223R polymorphism of the LEPR and obesity

The problem of overweight and obesity is one of the most urgent health issues in the world. 13 % of girls and 21 % of boys aged 11 suffer from overweight in the Russian Federation. The main causes of pubertal obesity are endocrine pathology, lifestyle and genetic disorders including mutation and polymorphisms of different metabolic pathways. Leptin produced in adipose tissue participates in reproduction regulation, glucose homeostasis, bone formation, etc. These effects are provided by leptin receptors coding LEPR gene. Q223R (rs1137101) polymorphism is associated with an increased serum level of leptin and overweight. There is no exact information about association between this polymorphism and obesity of adolescent females. The objective was to reveal LEPR Q223R polymorphism association between overweight and obesity in adolescent females. 123 Caucasian adolescent females were involved in this study. All samples could be separated into two groups: the girls with normal weight (SDS BM1 ± 1.0; control group), girls with overweight and obesity (SDS BM1 > +1.0-2.0; studied group). Anthropometric measurements (weight, height, waist and hip circumference, body fat percentage) were taken, and genotyping was performed using polymerase chain reaction with electrophoresis detection. G-allele frequency was 43.1 % in control and 40 % in the clinical group. We found no significant differences of the prevalence of polymorphism Q223R between the studied groups (р = 0,862). Furthermore, there was no association between the carriage of AG and GG with weight, BM1, body fat percentage, waist and hip circumference in both groups (р > 0.05). We have not found any association between LEPR Q223R and overweight and obesity in adolescent females

Metabolism and obesity: role of leptin receptor gene

Background. Currently more than 119 obesity-related polymorphisms is known to participate in adult obesity. One of them is LEPR Q223R. Many researches shown association of this polymorphism with adult obesity. However, the role of LEPR Q223R in adolescent overweight and obesity is the matter of dispute. Aim: to determine association of polymorphism Q223R of LEPR gene with some biochemical and hormonal measurements of blood in female adolescents with normal weight and with overweight and obesity. Materials and methods. A total of 103 female adolescents (14-17 years of age) was examined. All girls were divided into 2 groups: 43 girls with normal weight (SDS BM 10.311 ± 0.585), and 65 girls with overweight and obesity (SDS BMI 2.255± 0.739) (р < 0.0001). Height, weight, BM1, SDS BM1 were measured. Laboratory tests included triglycerides, total cholesterol and its fraction, TTH, free thyroxin and leptin. All girls were genotyped on carrier of LEPR Q223R. Statistical analysis was provided by software Statistica 8.0 using nonparametric Mann - Whitney methods and Chi-square test with Yates correction. Results. Significant association of carrying RR-genotype with increase of SDS BM1 (p = 0.006), THS (p = 0.006) and decrease of free thyroxin was shown in control group. Conclusion. Our results showed the association of R-allele with increase of SDS BM1, THS and decrease T4 free in control group

Some pharmacogenetic aspects of the <i>ABCB1</i> gene in lopinavir / ritonavir concentration variability in children with HIV infection: A pilot study

Polymorphic variants of the multidrug resistance gene (ABCB1 or MDR1) are associated with changes in the absorption and transport of drugs in the body. One of the substrates of the ABCB1 transporter is an antiretroviral drug from the class of protease inhibitors, lopinavir.   The aim. To research the effect of polymorphic variants C1236T and C3435T in the ABCB1 gene on the plasma concentration of lopinavir / ritonavir in children and adolescents living with HIV infection.   Methods. The genotypes of polymorphic variants of the ABCB1 gene were identified in 136 HIV infected children and adolescents; median age – 10 [7–12] years. The plasma concentration of lopinavir / ritonavir was measured from blood taken during the next scheduled appointment as part of dispensary observation at the Irkutsk Regional AIDS Centre using high performance liquid chromatography.   Results. The average duration of lopinavir/ritonavir use as part of an antiretroviral therapy was 55 months. Median viral load in patients was 1 [1–2.03] log 10  copies/ mL; the number of CD4 +  T cells – 38.36 %. The frequency of occurrence of the 3435T and 1236T alleles of the ABCB1 gene was ~50 %. In carriers of the 3435TT genotype, the median lopinavir concentrations 2 and 12 hours after drug intake were 5050.8 [3615.8–5847.7] and 2665.5 [216–4896.3] ng/mL, respectively. In carriers of the 1236TT genotype, median lopinavir concentrations 2 and 12 hours after drug intake were 4913.5 [3355.1–5733.7] and 3290.6 [159.1–4972.5] ng/mL, respectively.   Conclusions. The study did not reveal a significant relationship between the carriage of the C3435T and C1236T genotypes of the ABCB1 gene and the concentrations of lopinavir and ritonavir 2 and 12 hours after drug intake

FREQUENCIES OF POLYMORPHISMS IN THE CYTOCHROME’S P450 GENES OF WARFARIN TRANSFORMATION IN A EUROPEAN POPULATION OF EASTERN SIBERIA

Background. Genotypes of the cytochrome p450 isoform (CYP2C9 and CYP4F2) determine warfarin dose requirements. Frequencies of risk alleles and genotypes of CYP2C9 and CYP4F2 gene vary in different races and ethnic groups.Aim. This study analyzed the frequencies of *2, *3 alleles of CYP2C9 gene and the 1347 C&gt;T allele of CYP4F2 gene in the Caucasians of Eastern Siberia, and compare with other populations.Materials and methods. Participants were 147 patients (Caucasians): 67 (45.58 %) man and 80 (54.42 %) women), taking warfarin for the prevention of thrombosis with a mean age of 64.74 ± 14.29 years. There were patients with atrial fibrillation – 77 (52.38 %) persons, coronary artery disease – 10 (6.80 %), pulmonary embolism – 5 (3.40 %), 15 (10.20 %) patients after implantation of an mechanical heart valve, etc. The subjects were genotyped for CYP2C9 (*1,*2,*3), and CYP4F2 (1347 C&gt;T) by real-time polymerase chain reaction (RT-PCR) using “Pharmacogenetics Warfarin” reagent kits (DNA technology, Russia).Results. 69.4 % of Caucasians of Eastern Siberia (Russians), have two functional alleles (*1/*1) of CYP2C9 (they’re extensive/normal metabolizers), the number of intermediate metabolizers (*1/*2, *1/*3) was 29.8 % and 0.68 % of slow metabolizers (*3/*3). Homozygous carriers of two non-functional alleles *2 and *3 (*2/*2, *2/*3) were absent. Carriers of one coumarin-resistant Т-allele of CYP4F2 were 57 (38.7 %) respondents, two coumarin-resistant alleles – 10 (6.8 %) respondents.Conclusions. Frequencies of polymorphisms in the Cytochrome’s p450 genes of warfarin transformation in a European population of Eastern Siberia have no differences with other European populations of the worl

Pharmacogenetic Warfarin Dosing Algorithm in the Russian Population

Background. To date, there are many pharmacogenetic algorithms for selecting the dose of warfarin. However, there is very little information about the predictive accuracy of the algorithms. We decided to evaluate the predictive accuracy of the Gage algorithm, using a calculator, located on the web site (http://www.warfarindosing.org) in two ethnic groups (Caucasians and Asians), living in Russia.Aim. To compare the actual warfarin dose (AWD) to the calculated warfarin dose (CWD), using the algorithm in two ethnic groups taking warfarin.Materials and methods. We included 114 patients (66 Caucasians and 48 Asians): the mean age was60.91 ± 12.34 years; 61 (53.51 %) men, and 53 (46.49 %) women. The comparative characteristics of the algorithm were tested using the mean absolute error (MAE) between AWD and CWD, and percentage of patients, whose CWD fell within 20 % of AWD (percentage within 20 %). Genotyping for CYP2C9*2, CYP2C9*3, CYP4F*2 and VKORC1 was performed by real-time polymerase chain reaction (RT-PCR) method using Pharmacogenetics Warfarin reagent kits (DNA technology, Russia).Results. The Gage algorithm produced the predictive accuracy with MAE = 1.02 ± 0.16 mg/day and percentage within 20 % for Asian patients was 39.6 %. We obtained MAE = 1.33 ± 0.16 mg/day and percentage within 20 % for Caucasian patients was 40.9 %. In two ethnic groups (Caucasians and Asians) of the Russian population, overall performance of warfarin pharmacogenetic dosing by the Gage algorithm was similar.Conclusions. Despite the performance limitation of the current warfarin pharmacogenetic dosing Gage algorithm, constant international normalized ratio monitoring is important

Lavas from the Elbrus volcano, Greater Caucasus

Comprehensive geochronological and isotope-geochemical studies showed that the Late Quaternary Elbrus Volcano (Greater Caucasus) experienced long (approximately 200 ka) discrete evolution with protracted periods of igneous quiescence (approximately 50 ka) between large-scale eruptions. Volcanic activity of Elbrus is subdivided into three phases: Middle Neopleistocene (225-170 ka), Late Neopleistocene (110-70 ka), and Late Neopleistocene - Holocene (earlier than 35 ka). Petrogeochemical and isotope (Sr-Nd-Pb) signatures of Elbrus lavas point to their mantle-crustal origin. It was shown that hybrid parental magmas of the volcano formed due to mixing and/or contamination of deep-seated mantle melts by Paleozoic upper crustal material of the Greater Caucasus. Mantle reservoir that participated in genesis of Elbrus lavas as well as most other Neogene-Quaternary magmatic rocks of Caucasus was represented by the lower mantle "Caucasus" source. Primary melts generated by this source in composition corresponded to K-Na subalkali basalts with the following isotopic characteristics: 87Sr/86Sr = 0.7041+/-0.0001, e-Nd = +4.1+/-0.2, 147Sm/144Nd = 0.105-0.114, 206Pb/204Pb = 18.72, 207Pb/204Pb = 15.62, and 208Pb/204Pb = 38.78. Temporal evolution of isotope characteristics for lavas of the Elbrus Volcano is well described by a Sr-Nd mixing hyperbole between "Caucasus" source and estimated average composition of the Paleozoic upper crust of the Greater Caucasus. It was shown that, with time, proportions of mantle material in parental magmas of Elbrus gently increased: from ~60% at the Middle-Neopleistocene phase of activity to ~80% at the Late Neopleistocene - Holocene phase, which indicates an increase of activity of a deep-seated source at decreasing input of crustal melts or contamination with time. Unraveled evolution of the volcano with discrete eruption events, lacking signs of cessation of the Late Neopleistocene - Holocene phase, increasing contribution of the deep-seated mantle source in genesis of Elbrus lavas with time as deduced from isotope-geochemical data, as well as numerous geophysical and geological evidence indicate that Elbrus is a potentially active volcano and its eruptions may be resumed. Possible scenarios were proposed for evolution of the volcano, if its eruptive activity continued