The Association between Vitamin D Deficiency and variants of Vitamin D Binding protein gene among Healthy Iranian Adults.

Background: The high prevalence of vitamin D deficiency may be due to both genetic and environment factors. The aim of this study was to demonstrate that vitamin D deficiency may be due to variants of vitamin D binding protein (DBP) among otherwise healthy Iranian adults. Methods: This cross-sectional study was conducted on 265 healthy adults in Tehran. Anthropometric and biochemical parameters were assessed. Dietary vitamin D intake was assessed with a Food Frequency Questionnaire (FFQ), and participant DBP genotypes were determined by polymerase chain reactions - restriction fragment length polymorphism. Results: Significant associations were found between vitamin D status and low-density lipoprotein cholesterol (P < 0.001), total cholesterol (P < 0.001), and fasting blood sugar (P < 0.001), after adjustment for confounder factors. This study demonstrated that "rs7041" gene was associated with vitamin D deficiency (OR = 0.63, ß ± SE = -0.46 ± 0.14, P < 0.0001). After considering the "GG" genotype of the "rs7041" polymorphism as a reference, the prevalence of vitamin D deficiency was found to be higher in the individuals with "TT" genotype from the "rs7041" polymorphism. Conclusion: It was found that the prevalence of vitamin D deficiency was higher in individuals with T allele carriers in the "rs7041" polymorphism.

Association between dietary glycemic index and liver enzymes level among apparently healthy adults.

OBJECTIVE: The previous studies have revealed that there is a link between dietary glycemic index and lipid profile in overweight and obesity. The aim of study was to investigate whether the glycemic index is associated with liver enzymes. METHOD: Anthropometric and biochemical parameters were measured in 265 participants. Dietary glycemic index (GI) was assessed by using a validated food-frequency questionnaire. With adjusting confounder variable, Binary logistic regression was also used to predict the relationship between liver enzymes and quartile of intake. RESULTS: There was a significant difference between low and high GI diet for BMR (P = 0.01), FFM (P = 0.03), TG (P = 0.02), HDL (P = 0.002). The association between HDL and glycemic index remained significant after adjustment of sex and age (P = 0.03). Using the regression model following adjustment revealed that for each 1% increase in the degree of the GI, there was 11% elevation in liver enzyme abnormalities. In both groups of men and women, enzyme abnormalities positively correlated with GI, while only men showed remarkable correlation in all models (crude model: ß = 0.07, OR = 1.07, CI = 0.98to 1.16). Additionally, an increase in the degree of GI caused an elevation in enzyme abnormalities by 7%. With adjusting sex, age, BMI, and Physical activity, a significance correlation was found between GI and Enzyme abnormalities (p-value = 0.03, OR = 1.115). CONCLUSION: Our study indicated that high glycemic index diet led to the elevated levels of the liver enzymes, while being significant only in men.

The association between resting metabolic rate and metabolic syndrome May Be mediated by adipokines in overweight and obese women.

AIMS: Adipokines play a major role in developing metabolic syndrome (MetS), and it has been found that there is a significant relationship between MetS and resting metabolic rate (RMR) in obese people. The present study aimed to investigate the mediatory effect of adipokines on the RMR-MetS relationship. METHODS: This cross-sectional study included 263 obese and overweight women, mean BMI 33.28 (4.93) kg/m, and mean age 39.02 (11.60) who were assessed for RMR using indirect calorimetry. Moreover, using the body composition analyzer the Body composition was measured. Also, Enzyme-linked Immunosorbent Assay (ELISA) test provided a quantitative measurement of biochemical parameters. RESULTS: The results indicated that women in low RMR group had higher fat mass (P < 0.0001), FFM (P = 0.002), weight (P = 0.006), BMI (P < 0.0001), age (P = 0.01), and hs-CRP (P = 0.001). The results did not confirm any significant mediating roles for RBP4 (P = 0.051, ß = -0.28) and Vaspin (P = 0.06, ß = 0.32) in the RMR-MetS relationship. Additionally, after a binary regression test, Omentin-1 showed a significant mediating role (P = 0.25, ß = 0.04) as an interrelated agent to RMR and MetS. CONCLUSION: As this study shows, Omentin-1 was found to play a significant mediating role as a mediatory agent in relationship between RMR and MetS.

A High-Protein/Low-Fat Diet May Interact with Vitamin D-Binding Protein Gene Variants to Moderate the Risk of Depression in Apparently Healthy Adults.

BACKGROUND: Recent studies have shown that depression is inversely correlated with high protein and low fat intake and positively correlated with vitamin D-binding protein (VDBP). Therefore, the aim of this study was to examine the interaction between protein/fat dietary patterns and VDBP genotypes with regard to the risk of depression in apparently healthy adults who have not been diagnosed with any chronic disease. METHODS: In this study, 265 individuals (126 males and 139 females) aged 18-55 years were recruited from the communities of central and west Tehran based on convenience sampling. Body composition was measured with a body composition analyzer and depression symptoms were categorized as normal, moderate depression, or severe depression using the Depression Anxiety Stress Scales 21 (DASS-21) questionnaire. Dietary patterns were determined by a semiquantitative food frequency questionnaire to assess typical food intake during the 12-month period. Blood samples were collected from and biochemical measurements performed on all participants. An analysis of two polymorphisms (rs7041 and rs4588) in the GC gene, which encodes VDBP, was performed by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: A statistically significant association was found between depression and diet (p = 0.03) after having categorized the participants into three groups: a high-protein/low-fat (HP/LF) group, a moderate-protein/moderate-fat (MP/MF) group, and a low-protein/high-fat (LP/HF) group. Moreover, the findings demonstrated that depression was related to both the rs7041 and the rs4588 polymorphism (p = 0.05 and p = 0.02, respectively). We next used multinomial logistic modeling to investigate the risk of depression. A significant interaction was observed between HP/LF diet and the rs7041 polymorphism in the moderate- and severe-depression groups (ß = -0.30, p = 0.05, and ß = -0.48, p = 0.01, respectively). CONCLUSION: This study showed that an HP/LF diet interacts with the rs7041 polymorphism, with T allele carriers having a greater prevalence of moderate and severe depression.

Negative correlation of high-density lipoprotein-cholesterol and bone mineral density in postmenopausal Iranian women with vitamin D deficiency.

OBJECTIVE: The aim of the study was to investigate the association between high-density lipoprotein (HDL) and bone status taking into account serum vitamin D levels in postmenopausal Iranian women. METHODS: During January 2015 and February 2016, a total of 488 postmenopausal Iranian women participated in this cross-sectional study, all of whom were not taking osteoporosis medication and were not suffering from any chronic disorder. Dual X-ray absorptiometry was used to assess bone mineral density (BMD) of the total hip, femoral neck, and lumbar vertebrae (L2-L4). Each person was categorized based on the World Health Organization osteoporosis criteria in at least one skeletal region. At the end of the data collection, lipid profiles and vitamin D levels were measured for all participants. Vitamin D serum levels less than 30 ng/mL were defined as vitamin D deficiency or insufficiency. RESULTS: 27.9% of all participants displayed osteoporosis. Osteoporotic participants tended to be older with higher HDL serum levels (P < 0.001). No significant difference was seen in low-density of lipoprotein, total triglyceride, and total cholesterol levels among participants (P > 0.05). In a univariate model, after adjusting for age, menopausal age, obesity, physical activity, and use of antihyperlipidemic drugs (statins), there were significant negative associations among HDL levels and BMD values and T-score in the three regions (P < 0.004). Interestingly, after classification of participants based on vitamin D levels and adjustment for confounding factors, these significant negative associations between HDL levels and BMD values as well as T-score were observed only in participants with vitamin D deficiency or insufficiency, in the three regions (P < 0.008). CONCLUSIONS: Our data show that in postmenopausal women with vitamin D deficiency, serum levels of HDL have negative correlation with bone status.

Dietary fat intake associated with bone mineral density among visfatin genotype in obese people.

Osteoporosis and adipose tissue are closely related with many contradictions. Visfatin is an adipokine that is related to osteoporosis and adiposity. This nutrigenomics study examined the interaction between visfatin genotypes and dietary fat intake, with regard to bone mineral density (BMD) among an obese population. In this cross-sectional study, 336 subjects were enrolled; the mean age was 38·25 (sd 11·69) years and the mean BMI was 31·79 (sd 4·77) kg/m2. Laboratory measurements were lipid profile, insulin and fasting blood sugar. Bone density measurements were assessed by dual-energy X-ray absorptiometry. Dietary data were collected through a 3-d 24-h dietary recall. Genotyping for visfatin gene SNP (rs2110385) was performed by the PCR-restriction fragment length polymorphism method. The frequency of GG, GT and TT genotypes were 33·92 48·51 and 17·54 %, respectively, and 86·6 % of participants were women. The results showed that subjects with TT genotypes had significantly higher lumbar BMD, T score and z score (P<0·0001). After categorisation by percentage of fat intake (30 % of total energy content as a cut-off point), no interaction was found, but when categorised by fat types, we found an interaction between visfatin genotypes and dietary PUFA intake in terms of the hip T score and z score (P=0·043, B= -0·08; P=0·04, B= -0·078, respectively). There was a significant relationship between high PUFA intake and lower energy and protein intake. When participants were categorised by median PUFA intake (22·8 g), it was concluded that subjects with GG genotype who had high PUFA-intake diets had lower hip z scores and T scores, unlike the other genotypes.

The associations between dietary patterns and bone health, according to the TGF-ß1 T869→C polymorphism, in postmenopausal Iranian women.

BACKGROUND/OBJECTIVE: Recent studies have shown that dietary variants and genetic variants play a decisive role in the risk of developing osteoporosis. Therefore, the objective of the present study was to examine associations between dietary pattern and bone health, according to the TGF-ß1 T869→C polymorphism, in postmenopausal Iranian women. MATERIALS AND METHODS: In this study, 264 postmenopausal women aged from 46 to 78 years were examined. Body composition was measured by a body composition analyzer and physical activity by the short-form physical activity questionnaire. Bone mineral density was measured by the DEXA method. Dietary patterns were determined using factor analysis on 27 foods groups, employing a valid, reliable 147-item semi-quantitative food frequency questionnaire. The dietary patterns were analyzed by the factor analysis method. Blood samples were taken for measuring blood parameters. DNA samples from participants were genotyped using the RFLP-PCR method. RESULTS: Three dietary patterns were identified, namely: mediterranean diet, traditional diet, and unhealthy diet-one of which was associated with bone health. Postmenopausal women following a Mediterranean diet had lower weight and central obesity (0.05 > P). Higher adherence to a Mediterranean pattern was positively associated with Z-score L2_L4 lumbar spine (0.05 > P). TGF-ß1 T869→C genotypes, after adjustment, were not directly correlated with bone mineral density and body composition (0.05 < P). Moreover, these findings demonstrated that in participants adhering to a Traditional dietary pattern, the C allele carrier group (TC and CC genotypes) had a lower L2_L4 Z-score (P = 0.05). CONCLUSION: It seems that the mediterranean diet can be a beneficial dietary pattern in the prevention of osteoporosis and obesity in postmenopausal women. Furthermore (probably in the C allele carrier group), lower vitamin D intake, coupled with adherence to a traditional dietary pattern, reduces the deposition of TGF-beta and increases the risk of lumbar spine osteoporosis.

Vitamin D Status and Resting Metabolic Rate May Modify through Expression of Vitamin D Receptor and Peroxisome Proliferator-Activated Receptor Gamma Coactivator-1 Alpha Gene in Overweight and Obese Adults.

BACKGROUND: Resting metabolic rate (RMR) used to prognosticate and measure the amount of energy required. Vitamin D is known as a new predictor of RMR. The aim of this study is to investigate the relationship between vitamin D effects on RMR in connection with the vitamin D receptor (VDR) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) gene expression. METHODS: We enrolled 298 overweight and obese adults in this cross-sectional study. Body mass index (BMI), fat mass, fat-free mass, insulin level, visceral fat, and vitamin D status were assessed. RMR was measured by means of indirect calorimetry. The real-time polymerase chain reaction using specific primer pairs for VDR and PGC-1α was performed. RESULTS: There were significant differences in terms of fat free mass, fat percentage, insulin levels, RMR/kg body weight, and RMR/BMI, VDR, and PGC-1α among participants were categorized based on the vitamin D status. But after using general linear model for adjusting, all significant results missed their effectiveness except RMR/kg body weight and VDR. Linear regression analysis used to show the mediatory role of VDR and PGC-1α on the RMR/kg body weight and vitamin D status relationship. Our results showed that VDR had a mediatory effect on the relationship between RMR/kg body weight and vitamin D status (ß = 0.38, 95% CI -0.48 to 1.60; ß = -1.24, 95% CI -5.36 to 1.70). However, PGC-1α did not affect the relationship between RMR/kg body weight and vitamin D status (ß = 0.50, 95% CI = -0.02 to 3.42; ß = 0.59, 95% CI 0.14-3.90). CONCLUSION: Our study showed the mediatory effect of VDR gene expression in the association of 25(OH)2D plasma levels and resting metabolic rate among obese individuals.

Metabolically healthy/unhealthy components may modify bone mineral density in obese people.

Link between obesity and bone health is controversial. It seems that maybe the difference in metabolic status leads to this difference. We studied relation between metabolically healthy/unhealthy components with bone mineral density. Results showed metabolically unhealthy obesity (MUHO) phenotypes have better bone status at hip site than metabolically healthy obesity (MHO). Also, component metabolic can effect on BMD in different sites. PURPOSE/INTRODUCTION: This cross-sectional study aimed to compare total BMD and L-L4 BMD in MHO and MUHO base on Karelis criteria. METHODS: We enrolled 272 Iranian obese women and men (BMI ≥ 30). According to Karelis criteria, the participants were grouped base to MHO and MUHO. The body composition and BMD were assessed for all cases. Serum HDL-C, LDL-C, total cholesterol, triglyceride (TG), fasting blood glucose, homeostatic model assessment-insulin resistance (HOMA-IR), and hypersensitive C-reactive protein (hs-CRP) levels were quantified by ELISA method. RESULTS: Our results demonstrate MUHO phenotype have high total BMD more than MHO (P = 0.01, CI = 0.12 to 0.21). Also, the results of logistic regression analysis showed MUHO have strongly associated with total BMD (ß = -0.42, CI = - 0.31 to - 0.04, P = 0.009), but did not affected L2-L4 BMD (ß = - 0.09, CI = - 0.14 to 0.08, P = 0.578); this represents that there was discordance in MUHO subjects. Our evidence implicated that HOMA-IR, high level serum TG, hs-CRP, and low level serum HDL had mediatory effect on relationship between obesity and high BMD at the hip region in MUHO subjects (P < 0.05). CONCLUSION: Present evidence indicates that, could be a novel link between difference in MUH phenotype and MH phenotype with bone status. Also, component metabolic can effect on BMD in different sites.

Vitamin D Receptor Gene Variation, Dietary Intake and Bone Mineral Density in Obese Women: A Cross Sectional Study.

Osteoporosis and fragility fractures have been regarded as important public health concerns. We investigated their possible association with vitamin D receptor (VDR) FOK1 polymorphisms (rs10735810) and dietary parameters such as calcium and vitamin D intake. A total of 264 Iranian obese women (BMI>30 kg/m2) were categorized based on the FOK1 genotype and divided into two groups: group one with the FF genotype (n=184) and the f allele carrier group with the Ff or ff genotype (n=80). The body composition, dietary intake and bone mineral density were assessed for all cases. The frequency of the F and f alleles for FOK1 in the study were 71.5% and 28.5%, respectively. Women with the f allele had a higher BMI (p=0.05), as well as parathyroid hormone (PTH) and tumor necrosis factor alpha (TNF-α) concentration (p=0.05, p=0.01, respectively). Participants with calcium intakes of more than 1,000 mg/d and the ff genotype had a higher L2_L4 Z-score. Moreover, women with vitamin D intakes of less than 600 IU/d and the ff genotype had a higher total T-score and total Z-score. Although women whose dietary intake of vitamin D was higher than the recommended dietary allowance (RDA>600 IU/d) and had the FF genotype had a higher total T-score and total Z-score, as well. Our findings suggest that interactions between FOK1 polymorphisms in Iranian obese women and dietary intake of calcium and vitamin D may play a decisive role in bone mineral density and osteoporosis among these women.

Vitamin D (FokI) Receptor Gene Polymorphism is associated with Vitamin D Deficiency and Chronic Musculoskeletal Pain. A meta-analysis.

Background: Musculoskeletal pain is the most common chronic pain experienced by older adults. The aim of this study is to explore the associations between vitamin D (FOKI) receptor gene polymorphism (VDR) and vitamin D deficiency (VDD) and chronic musculoskeletal pain. Methods: Cross-sectional studies published in English from January 2000 to January 2015which reported prevalence of chronic pain (CP) and chronic musculoskeletal pain (CMP) were included in this systematic review and meta-analysis. A heat map was used to visualize and observe the correlation between VDR and CMP, CP and VDD. Results: 20 studies (N = 216,365) were included in the analysis, which showed an overall pooled prevalence estimate of CMP and CP as 30.6 per 100 (95 % CI: 30.59, 30.69) and 27.9 per 100 (95 % CI: 27.68, 28.24) respectively. The heat map clustering analysis visualizes the similarity between CP and CMP. Moreover, a direct correlation was observed between the three disease conditions (namely CMP, CP, and VDD) and FokI VDR polymorphism (FF). Spearman's correlation analyses with adjusted r2 revealed that there is a statistically significant interaction effect of the FF genotype and VDD on CMP (r2 = 0.19, p = 0.03), a marginally significant interaction effect of the ff genotype and VDD on CMP (r2 = 0.11, p = 0.08). VDD was also associated with increased CMP (r2 = 0.19, p = 0.028). The pooled estimates of the prevalence of CMP in this review were found to be high. Conclusion: FokI VDR gene polymorphism (FF) plays an important role in the relationship between VDD and CMP.