Are variants of the RBP4 gene associated with serum retinol-binding protein 4 concentrations and carotid intima-media thickness values in women with obesity?

INTRODUCTION

Several studies showed the correlation of retinol-binding protein 4 (RBP4) with increased cardiovascular risk - including higher values of carotid intima-media thickness (cIMT) - particularly in individuals with obesity.

OBJECTIVES

Our study aimed to investigate the impact of rs10882273; rs3758538; rs3758539, and rs7094671 RBP4 gene variants on RBP4 serum concentrations as well as cIMT values (a marker of subclinical atherosclerosis) among female patients with obesity.

PATIENTS AND METHODS

We recruited 74 women with obesity and 24 women without obesity as a study and control group, respectively. The genotypic and allelic frequencies of RBP4 gene variants were evaluated for associations with serum RBP4 and cIMT.

RESULTS

The median serum RBP4 concentrations were 20.30 µg/mL and 19.80 µg/mL in the patients and control group, respectively (p = 0.740). No significant differences were seen in cIMT values between the two studied groups (0.60 [0.50-1.00] vs. 0.60 ± 0.10 in the patient and control group, respectively); however, the results were close to reaching significance (p = 0.071), similar as in observed association of the minor haplotype AA for rs7084671 and rs375839 with female obesity (p = 0.0559). The correlation analysis showed no significant differences between RBP4 gene variants with serum RBP4 and cIMT.

CONCLUSIONS

According to our knowledge, this is the first study investigating the association between RBP4 gene variants and serum RBP4 and cIMT among Polish female patients with obesity. However, our results show that genetic variants rs10882273, rs3758538, rs3758539, and rs7094671 of the RBP4 gene are not associated with RBP4 serum concentrations or cIMT values among women with obesity.

Where Do We Stand in the Behavioral Pathogenesis of Inflammatory Bowel Disease? The Western Dietary Pattern and Microbiota-A Narrative Review

Despite the increasing knowledge with regard to IBD (inflammatory bowel disease), including ulcerative colitis (UC) and Crohn’s disease (CD), the etiology of these conditions is still not fully understood. Apart from immunological, environmental and nutritional factors, which have already been well documented, it is worthwhile to look at the possible impact of genetic factors, as well as the composition of the microbiota in patients suffering from IBD. New technologies in biochemistry allow to obtain information that can add to the current state of knowledge in IBD etiology.

Does the VDR gene polymorphism influence the efficacy of denosumab therapy in postmenopausal osteoporosis?

INTRODUCTION

One of the challenges of personalized medicine is a departure from traditional pharmacology toward individualized, genotype-based therapies. Postmenopausal osteoporosis is a prevalent condition requiring intensive treatment, whose effects are measurable only after a long time, and the goal is bone fracture prevention. This study aimed to determine the influence of VDR gene variation on anti-osteoporotic one-year treatment with denosumab in 63 Polish women with postmenopausal osteoporosis.

MATERIALS AND METHODS

The correlation between bone mineral density (BMD) of the lumbar vertebral column (L1-L4) and femoral neck, and genotype distributions for the ApaI, BsmI, FokI, and TaqI variants of the VDR gene was analyzed. Bone fractures during denosumab therapy were also investigated.

RESULTS

In the case of the Bsml polymorphism, female patients with BB and Bb genotypes had statistically significantly higher values of BMD and T-score/Z-score indicators, which persisted after a year of denosumab treatment. Our results indicated that the Bsml polymorphism contributes to better bone status, and, consequently, to more efficient biological therapy. The study did not reveal significant differences between changes (delta) in BMD and genotypes for the analyzed VDR gene loci. In the entire study group, one bone fracture was observed in one patient throughout the yearlong period of denosumab therapy.

CONCLUSIONS

BB and Bb genotypes of the Bsml polymorphism of the VDR gene determine higher DXA parameter values both before and after one-year denosumab therapy in postmenopausal women with osteoporosis.

Myostatin and Follistatin-New Kids on the Block in the Diagnosis of Sarcopenia in IBD and Possible Therapeutic Implications

Sarcopenia, which is a decrease in muscle strength and quality of muscle tissue, is a common disorder among patients suffering from inflammatory bowel disease. This particular group of patients often presents with malnutrition and shows low physical activity, which increases the risk of sarcopenia. Another important factor in the development of sarcopenia is an imbalanced ratio of myostatin and follistatin, which may stem from inflammation as well as genetic factors. Currently, research in this area continues, and is aimed at identifying an effective medication for the treatment of this condition. Additionally, we still have no sarcopenia markers that can be used for diagnosis. In this paper, we address the role of myostatin and follistatin as potential markers in the diagnosis of sarcopenia in patients with Crohn’s disease and ulcerative colitis, particularly in view of the genetic and biological aspects. We also present data on new perspectives in the pharmacotherapy of sarcopenia (i.e., myostatin inhibitors and gene therapy). Nevertheless, knowledge is still scarce about the roles of follistatin and myostatin in sarcopenia development among patients suffering from inflammatory bowel disease, which warrants further study.

Vitamin D, Vitamin D Receptor (VDR) Gene Polymorphisms (ApaI and FokI), and Bone Mineral Density in Patients With Inflammatory Bowel Disease

In the etiology of inflammatory bowel disease (IBD) and osteoporosis, the connecting element is the involvement of environmental and genetic factors. Vitamin D receptor (VDR) gene polymorphisms may be associated with the pathogenesis of IBD and bone mineral density (BMD). The study aimed to analyze the relationship between ApaI and FokI polymorphisms of the VDR gene, serum vitamin D concentration, and BMD in patients with IBD. The studied group consisted of 172 patients (85 with Crohn's disease [CD], 87 with ulcerative colitis [UC], and 39 healthy subjects - control group [CG]) were examined. Lumbar spine densitometry (L1-L4) and the femoral neck (FN) measurements were performed using dual-energy X-ray absorptiometry (DXA). Serum concentrations of 25-hydroxyvitamin D were determined using electrochemiluminescence binding assay (ECLIA). Polymorphisms were determined with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). . We found no statistically significant differences in vitamin D concentration between the 3 studied groups. CD patients who were FF homozygotes had significantly lower FN BMD than FF homozygous from CG (p-value < 0.05). CD patients who were Aa heterozygotes had significantly lower lumbar spine (L2-L4) BMD than Aa heterozygotes from CG (p-value < 0.05). Among patients with the same polymorphic variants, but belonging to different studied groups, statistically significant differences in bone mineral density in the lumbar spine and the closer end of the femoral neck were observed. We consider that it is the disease entity, not the polymorphism variant, may have a decisive impact on BMD.

ESR1 Gene Variants Are Predictive of Osteoporosis in Female Patients with Crohn's Disease

Decreased bone mass in patients with inflammatory bowel diseases (IBD) is a clinical problem with extremely severe consequences of osteoporotic fractures. Despite its increasing prevalence and the need for mandatory intervention and monitoring, it is often ignored in IBD patients’ care. Determining the biomarkers of susceptibility to bone mineral density disorder in IBD patients appears to be indispensable. We aim to investigate the impact of estrogen receptor gene (ESR1) gene polymorphisms on bone mineral density (BMD) in patients with ulcerative colitis (UC) and Crohn’s disease (CD), as they may contribute both, to osteoporosis and inflammatory processes. We characterised 197 patients with IBD (97 with UC, 100 with CD), and 41 controls carrying out vitamin D, calcium and phosphorus serum levels, and bone mineral density assessment at the lumbar spine and the femoral neck by dual-energy X-ray absorptiometry (DXA), ESR1 genotyping and haplotype analysis. We observed that women with CD showed the lowest bone density parameters, which corresponded to the ESR1 c.454-397T and c.454-351A allele dose. The ESR1 gene PvuII and XbaI TA (px) haplotype correlated with decreased femoral neck T-score (OR = 2.75, CI = [1.21–6.27], P-value = 0.016) and may be predictive of osteoporosis in female patients with CD.

Vitamin D receptor (VDR) TaqI polymorphism, vitamin D and bone mineral density in patients with inflammatory bowel diseases

BACKGROUND

A common feature in the etiology of inflammatory bowel disease (IBD) and osteoporosis is a complex genetic background. Moreover, it has been shown that some of the susceptibility loci overlap for both diseases. One of the genes that may be involved in the pathogenesis of IBD as well as decreased bone mass is the vitamin D receptor (VDR) gene.

OBJECTIVES

The aim of this study was to investigate the association of the TaqI polymorphism (rs731236, c.1056T >C) in the VDR gene with serum vitamin D concentration and bone mineral density (BMD) in patients with IBD.

MATERIAL AND METHODS

A total of 172 IBD patients (85 with Crohn's disease (CD) and 87 with ulcerative colitis (UC)) and 39 healthy controls were enrolled in the study. Polymorphism was determined with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Bone mineral density was measured at the lumbar spine (L2-L4) and the femoral neck (FN) using dual-energy x-ray absorptiometry (DEXA). Serum concentrations of 25-hydroxyvitamin D were determined using electrochemiluminescence binding assay (ECLIA).

RESULTS

Our studies revealed that serum vitamin D concentration in IBD patients was not lowered in comparison with healthy controls. Patients with CD presented more advanced osteopenia and osteoporosis. Individuals with UC carrying the TaqI tt genotype of VDR gene showed significantly higher FN BMD than carriers of TT and Tt genotypes (p = 0.02). Moreover, tt genotype was present with higher frequency in UC patients than in controls and CD patients (23% vs 7.7% and 16.5%, respectively).

CONCLUSIONS

The tt genotype may have a protective effect on BMD in UC patients.

Pharmacogenetics of Cannabinoids

Although the application of medical marijuana and cannabinoid drugs is controversial, it is a part of modern-day medicine. The list of diseases in which cannabinoids are promoted as a treatment is constantly expanding. Cases of significant improvement in patients with a very poor prognosis of glioma or epilepsy have already been described. However, the occurrence of side effects is still difficult to estimate, and the current knowledge of the therapeutic effects of cannabinoids is still insufficient. In our opinion, the answers to many questions and concerns regarding the medical use of cannabis can be provided by pharmacogenetics. Knowledge based on proteins and molecules involved in the transport, action, and metabolism of cannabinoids in the human organism leads us to predict candidate genes which variations are responsible for the presence of the therapeutic and side effects of medical marijuana and cannabinoid-based drugs. We can divide them into: receptor genes-CNR1, CNR2, TRPV1, and GPR55, transporters-ABCB1, ABCG2, SLC6A, biotransformation, biosynthesis, and bioactivation proteins encoded by CYP3A4, CYP2C19, CYP2C9, CYP2A6, CYP1A1, COMT, FAAH, COX2, ABHD6, ABHD12 genes, and also MAPK14. This review organizes the current knowledge in the context of cannabinoids pharmacogenetics according to individualized medicine and cannabinoid drugs therapy.

The c.29T>C polymorphism of the transforming growth factor beta-1 (TGFB1) gene, bone mineral density and the occurrence of low-energy fractures in patients with inflammatory bowel disease

Gastrointestinal tract conditions are frequently associated with low bone mineral density and increased risk of fractures due to osteoporosis, the latter concerning particularly inflammatory bowel disease (IBD) patients. One of the candidate genes involved in osteoporosis is the transforming growth factor beta-1 (TGFB1) whose polymorphisms may be responsible for the development of this disease. The aim of this study was to analyse the frequency of TGFB1 polymorphic variants and determine the association between the c.29T>C TGFB1 polymorphism, and bone mineral density and fractures in IBD patients. The study subjects included 198 IBD patients [100 suffering from Crohn's disease (CD) and 98 from ulcerative colitis (UC)] and 41 healthy volunteers as a control group. Densitometric bone measurements were obtained using dual energy X-ray absorptiometry. The TGFB1 genotyping was conducted using restriction fragments length polymorphism. We conducted an analysis of genotype distribution's concordance with Hardy-Weinberg equilibrium. We found statistically significant differences in lumbar spine (L2-L4) and femoral neck BMD and T-scores between CD, UC and control subgroups. The distribution of TGFB1 polymorphic variants among CD and UC patients was concordant with Hardy-Weinberg equilibrium. There were no statistically significant differences in densitometric parameters (lumbar spine and femoral neck BMD, T-score, and Z-score) between carriers of different TGFB1 polymorphisms among IBD (CD and UC) patients nor among controls. We have found no statistically significant differences in the prevalence of low-energy fractures between groups of different TGFB1 polymorphic variant carriers. The allele dose effect, recessive effect and dominant effect analysis did not show an association between low-energy fractures and the TGFB1 polymorphisms among CD and UC patients. We have not observed an association between the c.29T>C TGFB1 polymorphic variant and the bone mineral density within the cancellous and cortical bones (L2-L4 and femoral neck, respectively), or the occurrence of fractures among the IBD patients and their family members.

Bitter taste of Brassica vegetables: The role of genetic factors, receptors, isothiocyanates, glucosinolates, and flavor context

It is well known that consumption of Brassica vegetables has beneficial effect on human's health. The greatest interest is focused on glucosinolates and their hydrolysis products isothiocyanates, due to their potential as cancer preventing compounds. Brassica vegetables are also rich in flavor compounds belonging to many chemical groups. The main sensory sensation related to these vegetable is their characteristic sharp and bitter taste, and unique aroma. Because of these features this group of vegetables is often rejected by consumers. Interestingly, for some people unpleasant sensations are not perceived, suggesting a potential role of inter-individual variability in bitter taste perception and sensibility. Receptors responsible for bitter sensation with the emphasis on Brassica are reviewed, as well as genetic predisposition for bitterness perception by consumers. Also the role of glucosinolates and isothiocyanates as compounds responsible for bitter taste is discussed based on data from the field of food science and molecular biology. Isothiocyanates are shown in broaded context of flavor compounds also contributing to the aroma of Brassica vegetables.

Bone Metabolism and the c.-223C > T Polymorphism in the 5'UTR Region of the Osteoprotegerin Gene in Patients with Inflammatory Bowel Disease

Osteoporosis is more frequent in inflammatory bowel disease (IBD) patients. A reduction in bone mineral mass in these individuals is caused not only by inflammatory processes in the bowel, because osteoporosis occurs already in very young IBD patients and in newly diagnosed individuals who have not yet undergone any pharmacological treatment. One of individual determinants of the bone turnover parameters is osteoprotegerin (OPG) encoded by the TNFRSF11B gene. The c.-223C > T polymorphism in this gene has been extensively studied in post-menopausal osteoporosis patients. However, no such studies exist for osteoporosis related to IBD. The aim of our study was to determine whether the c.-223C > T (rs2073617) polymorphism in the 5'UTR region of the gene encoding osteoprotegerin is a functional polymorphism which may change the gene expression and resulting OPG levels, and so be associated with osteopenia and osteoporosis, and impaired bone metabolism in Crohn's disease and ulcerative colitis patients. Our study included 198 IBD patients and 41 healthy controls. Lumbar spine and femoral neck bone mineral density, T-score, Z-score as well as OPG, RANKL, vitamin D, calcium and interleukin 4 and 10 concentrations were determined for all study subjects. Genotyping of the TNFRSF11B polymorphic site was performed by restriction fragment length polymorphism technique. Statistical analyses were conducted using Statistica software. Odds ratios, 95 % confidence intervals, and P values were calculated using the HWE calculator. Our results did not allow determining an unequivocal association between the polymorphic variants of the TNFRSF11B 5'UTR region and a susceptibility to osteoporosis in IBD patients. We have shown, however, that the c.-223T allele was twice as more frequent in Crohn's disease (CD) patients than among controls (OR = 1.99, P value = 0.009). Interestingly, average osteoprotegerin levels in CD patients did not significantly differ from those in controls, whereas in ulcerative colitis patients, OPG levels were significantly lower. We have concluded that low OPG levels may be associated with osteoporosis in ulcerative colitis, but it is not correlated with the c.-223C > T polymorphism in the TNFRSF11B gene. In CD patients, in turn, we observed increased RANKL levels. Our observations confirm different pathogeneses of Crohn's disease and ulcerative colitis as well as different molecular backgrounds of osteoporosis associated with these two diseases.

Ecosensitivity and genetic polymorphism of somatic traits in the perinatal development of twins

In view of criticism regarding the usefulness of heritability coefficients, the aim of this study was to analyze separately the information on genetic and environmental variability. Such an approach, based on the normalization of trait's variability for its value, is determined by the coefficients of genetic polymorphism (Pg) and ecosensitivity (De). The studied material included 1263 twin pairs of both sexes (among them 424 pairs of monozygotic twins and 839 pairs of dizygotic twins) born between the 22nd and 41st week of gestation. Variability of six somatic traits was analyzed. The zygosity of same-sex twins was determined based on the polymorphism of DNA from lymphocytes of the umbilical cord blood, obtained at birth. The coefficients of genetic polymorphism and ecosensitivity for analyzed traits of male and female twins born at various months of gestation were calculated. Our study revealed that a contribution of the genetic component predominated over that of the environmental component in determining the phenotypic variability of somatic traits of newborns from twin pregnancies. The genetically determined phenotypic variability in male twins was greater than in the females. The genetic polymorphism and ecosensitivity of somatic traits were relatively stable during the period of fetal ontogeny analyzed in this study. Only in the case of body weight, a slight increase in the genetic contribution of polygenes to the phenotypic variance could be observed with gestational age, along with a slight decrease in the influence of environmental factors.

Heritability estimates for somatic traits determined perinatally with the twin method

The aim of this study was to establish estimates for heritability of somatic traits determined perinatally with the twin method. The studied material, including 1263 twin pairs live-born at various stages of prenatal life, i.e. between the 22nd and 41st week of gestation, was collected at the Department of Perinatology and Gynecology, Poznań University of Medical Sciences, between 2002 and 2009. The zygosity of 821 pairs of same-sex twins was determined at the Laboratory of Molecular Genetics in Poznań using analysis of single and multiple nucleotide polymorphisms. The proportion of phenotypic variance explained by genetic variability was determined using heritability indices based on intrapair variances and correlations. Analysis of these indices revealed that genetic variability predominated over environmental variability in determining the phenotypic variance of all studied traits. Heritability was the highest for body weight and shoulder width. The high values of heritability coefficients documented in our study were to a certain extent associated with an inconsistency of the assumption on the additive effect of genetic and environmental effects. While analyzing the phenotypic variance of a trait, the role of genotype-environment interactions and covariance cannot be ignored, as these are their effects which increase the genetic variance and related coefficients of heritability. Therefore, it can be concluded that the genotypic component of the phenotypic variance of the trait is enhanced by the effects of various environmental factors.

The c.470 T > C CHEK2 missense variant increases the risk of differentiated thyroid carcinoma in the Great Poland population

BACKGROUND

Differentiated thyroid carcinoma (DTC) originates from thyroid follicular epithelial cells and belongs to a group of slowly progressing tumors with a relatively good prognosis. However, recurrences and metastases are a serious problem in advanced stages. Furthermore, progression from a well differentiated thyroid carcinoma to an aggressive anaplastic one is possible. The majority of differentiated thyroid carcinomas are sporadic but a few alleles increasing the cancer risk are known. One of them is the c.470 T > C (p.I157T, rs17879961) missense substitution in the CHEK2 gene.

AIM OF THE STUDY

The aim of this study was to investigate whether this specific CHEK2 alteration, c.470 T > C, predisposes the Great Poland (Wielkopolska) population to thyroid cancer.

METHODS

602 differentiated thyroid carcinoma patients and 829 controls randomly selected from population were genotyped for the presence of the c.470C allele using pyrosequencing. Hardy-Weinberg Equilibrium (HWE) was tested for both groups by chi-square distribution and Fisher's exact test. The odds ratios (ORs), 95% confidence intervals (CIs), and p-values were calculated using the R software.

RESULTS

The results of genotyping showed the presence of the c.470C allele in 51 patients with a frequency of 4.49%, while in a controls in 42 patients with a frequency of 2.53%. We demonstrated that in the Great Poland population the c.470C CHEK2 variant increases the risk of developing differentiated thyroid cancer almost twice (OR = 1.81, p = 0.004). The risk of papillary thyroid carcinoma in female patients homozygous for the c.470C allele was shown to increase almost 13-fold (OR = 12.81, p = 0.019).

CONCLUSIONS

Identification of c.470C CHEK2 gene variant ought to be taken into account by healthcare policymakers. Future well-designed and larger population studies are of great value in confirming these findings. Moreover, a combination of genetic factors together with environmental exposures should also be considered.

Successful production of piglets derived from mature oocytes vitrified using OPS method

OBJECTIVE

Examination of effect of vitrification solution with or without foetal calf serum (FCS) on the in vitro and in vivo survival of matured pig oocytes.

MATERIALS AND METHODS

Exp. 1: oocytes were exposed to vitrification solutions: VSa (15% DMSO, 15% EG, 0.5 M sucrose dissolved in TCM-199 with FCS) or VSb (VSa without FCS). Exp. 2: oocytes were vitrified in VSa or VSb using OPS. A fraction of vitrified oocytes were transferred to 6 synchronised and inseminated recipients..

RESULTS

Survival rate after exposure and vitrification was the same for VSa and VSb. Transfer of 48 oocytes vitrified in VSb resulted with two pregnancies and 12 live piglets. Molecular analysis results: eight piglets originated from the surrogate mother's oocytes, four piglets from vitrified oocytes..

CONCLUSION

The use of DMSO and EG as cryoprotectants without serum supplementation was advantageous for the in vivo development of vitrified mature porcine oocytes.

CCND1 gene polymorphic variants in patients with differentiated thyroid carcinoma

Alterations in the CCND1 gene affect the cell cycle and are frequently observed in a variety of cancers. While the most frequent mutations that occur in thyroid tumor tissue have been characterized, the genetic factors that predispose individuals to differentiated thyroid cancer (DTC) remain to be elucidated. The present study examined whether the CCND1 c.723G>A (rs9344; p.Pro241=) and c.669C>T (rs3862792; p.Phe223=) variants have an impact on DTC susceptibility. A cohort consisting of 652 patients diagnosed with DTC were analyzed and comapred with a reference group of 799 subjects from the general population. Pyrosequencing was used as the genotyping technique. In order to determine the statistical significance of differences observed in the genotypic and allelic frequencies between the compared groups, GraphPad Prism 4 was used. At the rs9344 locus in the DTC patients, a higher frequency of allele A [P=0.032; odds ratio (OR), 1.18; 95% confidence interval (CI), 1.014–1.361] and the AA homozygous genotype (P=0.028; OR, 1.41; 95% CI, 1.059–1.989) was observed compared with the control population group. The differences were stronger for papillary carcinomas (OR 1.45; 95% CI, 1.059–1.989), but were not significant in follicular tumors. No statistically significant differences were noted in the frequency of genotypes or alleles at the rs3862792 locus in the examined groups. The present findings indicate that the c.723A variant of the CCDN1 gene may be a susceptibility low penetrance allele in the development of papillary thyroid cancer in the population studied, however it does not impact on multifocality, metastatic ability or age at diagnosis. A cumulative effect of the analyzed CCND1 gene variants was also excluded.

Microchimerism in twins

INTRODUCTION

The aim of this paper was to report the occurrence of peripheral blood chimerism in newborns from bigeminal pregnancies.

MATERIAL AND METHODS

Cord blood collected from 50 pairs of twins constituted the biological material studied. Analyses included: DNA isolation, quantitative and qualitative assessment of DNA preparations, hybridization analysis of SLS type as well as of MLS type, and analysis of microsatellite sequences with regard to polymorphisms using polymerase chain reaction.

RESULTS

The presence of additional fragments of DNA in peripheral blood lymphocytes was found in four out of fifty pairs of monozygotic twins (8%) at locus D7S21 (7p22, n = 3) and locus D12S11 (12q24.3, n = 1). In these cases, the presence of additional DNA fragments was also proved by analysis of microsatellite sequence polymorphisms at loci HUMPLA2A1 (pancreatic phospholipase A-2, 12q23), HUMCYARO (cytochrome P450, 15q21.1) and HUMvWF (von Willebrand factor, 12p13).

CONCLUSIONS

The results of our study confirm the occurrence of chimerism in twins and constitutes the starting point for further studies aimed at determining the clinical significance of chimerism in twins both for women and fetuses.