Relationship Between Vitamin D Receptor Gene Polymorphisms and Risk of Ulcerative Colitis: A Meta-analysis / 胃肠病学

Background: Vitamin D receptor (VDR) is associated with the occurrence and development of ulcerative colitis (UC). The expression and function of VDR may be affected by its gene polymorphisms, and thus affecting the occurrence of UC. However, results of studies are still in controversary. Aims: To explore the relationship between VDR gene polymorphisms and UC. Methods: Studies on correlation of VDR gene (Apa, Bsm, Fok, Taq) polymorphisms with UC were retrieved from SinoMed, CNKI, Wanfang, VIP, Embase, PubMed, The Cochrane Library databases. Literatures were enrolled according to the inclusion and exclusion criteria, and the data were extracted. RevMan 5.3 was used to conducted meta-analysis. Results: A total of 11 studies involving 1 811 UC patients were included. Meta-analysis showed that VDR gene Fok polymorphism (FF + Ff vs. ff: OR=0.67, 95% CI: 0.49-0.92, P=0.01), allele (F vs. f: OR=0.81, 95% CI: 0.68-0.96, P=0.02) were significantly correlated with the susceptibility of UC. Among which, Fok polymorphism (FF+Ff vs. ff: OR=0.59, 95% CI: 0.37-0.94, P=0.03), allele (F vs. f: OR=0.76, 95% CI: 0.60-0.97, P=0.03) were significantly correlated with the susceptibility of UC in Asian, but not in Caucasian population (P>0.05). No significant association was observed between Apa, Bsm, or Taq polymorphisms and UC (P>0.05). Conclusions: Existing evidence shows that VDR gene Fok polymorphism might contribute to UC susceptibility, however, Apa, Bsm, and Taq polymorphisms might not be significantly correlated with UC.

Serum 25-hydroxyvitamin D inversely associated with blood eosinophils in patients with persistent allergic rhinitis

OBJECTIVE: The relationship between vitamin D and allergic rhinitis (AR) remains unclear. The present study investigated their association by examining serum 25-hydroxyvitamin D (25(OH)D) levels, blood eosinophils, and the expression of vitamin D receptors (VDR) on nasal mucosa in patients with AR. METHODS: A total of 32 patients with persistent AR and 25 controls were enrolled in this study. Serum 25(OH)D levels were detected by enzyme-linked immunosorbent assay, and eosinophils in the peripheral blood were examined by an automated hematology system, while VDR expression on inferior turbinate mucosa was assessed by immunohistochemistry. Furthermore, the correlation of serum 25(OH)D levels with blood eosinophils in persistent AR was analyzed. RESULTS: No significant difference in serum 25(OH)D levels was detected between the AR and control groups (p = 0.371). Interestingly, the serum 25(OH)D levels of the AR group were negatively correlated with blood eosinophil count and its proportion (p = 0.019 and p = 0.010, respectively) even when adjusting confounding factors including age, sex, body mass index, and the season of blood sampling. On the other hand, no significant difference in the expression levels of VDR on nasal mucosa was found between the AR group and the control group (p = 0.231). CONCLUSION: These results suggest that the serum 25(OH)D might be inversely associated with blood eosinophils in patients with persistent AR. However, the relationship between vitamin D and AR still requires further clarification

Effect of vitamin D on overload-induced hypertrophy of skeletal muscle and expression of vitamin D receptor in aged rats / 第二军医大学学报

Objective To establish an overload-induced hypertrophy model in aged rats by severing the distal tendon of gastrocnemius muscle, and to investigate the effect of vitamin D on overload-induced hypertrophy and the related mechanism. Methods A total of 20 male rats (24 months old) underwent tenotomy of the achilles tendon of the gastrocnemius muscle in the left hind limb; and a control sham operation was performed on the right hind limb. The rats were randomly divided into control group and experimental group. Experimental group received 1 000 IU/kg of vitamin D by intragastric administration, and the control group was given soybean oil. The animals were sacrificed one week later, the blood samples were collected, and the left, right hind musculus plantaris tissues were weighed and kept in liquid nitrogen. ELISA assay was used to examine serum 25(OH)D level and vitamin D receptor (VDR) in the skeletal muscle. Western blotting analysis was used to examine mTOR, rpS6 protein and their phosphorylation. Results The food intake and body mass were not significantly different between the two groups. Compared with the control side, vitamin D supplement significantly increased the muscle mass of the overload side in both groups (P<0. 05); and the mass of the overload side in the vitamin D supplement group was significantly higher than that in the control group (P<0. 05), while the mases were not significantly different for the sham sides in the two groups. The results of ELISA assay showed that vitamin D supplement significantly increased serum 25(OH)D levels in rats compared with the control group (P< 0. 05), and significantly promoted the expression of VDR in the overload side compared with the Sham side (P<0. 05), while there was no significant difference between the two sides in the control group. Western blotting analysis showed that p-rpS6/rpS6 and p-mTOR/mTOR ratios in the overload sides were higher than those in the Sham sides, but significant difference was only found for the vitamin D supplement group (P<0. 05). Conclusion Tenotomy of the achilles tendon of the gastrocnemius muscle can effectively promote the skeletal muscle hypertrophy in aging rats, and vitamin D supplement can further enhance overload-induced skeletal muscle hypertrophy, which might be related to VDR expression in skeletal muscle and protein synthesis protein mTOR and rpS6.

Association of vitamin D receptor gene polymorphisms with susceptibility to coal-burning borne fluorosis in Guizhou province / 中国地方病学杂志

ObjectiveTo observe the distribution of vitamin D receptor(VDR) gene polymorphisms in coal-burning borne fluorosis in Guizhou province and investigate the relationship between VDR gene polymorphisms and the susceptibility to coal-burning borne fluorosis.MethodsOne hundred and fifty villagers from non-improving cooking stove villages were selected as a non-intervention group in Bijie area,Guizhou province where coal-burning borne fluorosis was prevailing; 150 villagers were chosen from cooking stove improved villages as a intervention group; 150 villagers were selected from non-endemic area Changshun county as a control group.DNA was extracted from peripheral blood samples of these people.Genotype of VDR gene Bsm Ⅰ and Fok Ⅰ loci were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).ResultsDistribution of Bsm Ⅰ polymorphism site of VDR gene of control group [AA:19.3％ (29/150),AG:39.3％ (59/150),GG:41.3％(62/150)],was compared with that[AA:4.7％(7/150),AG:14.0％(21/150),GG:81.3％(122/150)] of the non-intervention group and that[AA:7.3％(11/150),AG:23.3％(35/150),GG:69.3％(104/150)] of intervention group,and the difference was statistically significant(X2 =56.6,P ＜ 0.05).The frequency of VDR-Fok Ⅰ loci in non-intervention group [TT:29.3％(44/150),TC:55.3％(83/150),CC:15.3％(23/150)] and intervention group [TT:32.7％(49/150),TC:55.3％(83/150),CC:12.0％(18/150)] was compared with that [TT:45.3％(68/150),TC:48.7％(73/150),CC:6.0％(9/150)] of control group,and the difference was statistically significant(X2 =11.9,P ＜ 0.05).Univariate analysis showed that individuals carrying the GG genotype had increased risk of suffering fluorosis than individuals carrying the AA and AG genotypes(OR values were 6.2,3.2,all P ＜ 0.05),while carrying the TC and CC genotype had increased risk of suffering fluorosis than individuals carrying the TT genotype (OR values were 1.3,2.8,1.3,2.1,all P ＜ 0.05).ConclusionVDR gene polymorphisms may be one of the predisposing factors of coal-burning borne fluorosis.

Mapk signal pathway is involved in 17β-estrodial-induced upregulation of vitamin D receptor in osteoblasts / 第二军医大学学报

Objective To explore the regulatory effect of 17β-estrodial on vitamin D receptor (VDR) expression in pre-osteoblasts and the involvement of MAPK signal pathway in the process. Methods MC3T3-E1 subclone 14 cells were cultured in phenol-red free medium supplemented with 10% fetal bovine serum (FBS). Serum free medium was used when the cells were experimentally treated. After the cells were treated with 17β-estrodial for pre-determined time periods, expressions of vitamin D receptor (VDR) mRNA and protein were determined by SYBR green-based quantitative PCR and Western blotting analysis, respectively, and the activation of MAPK in MC3T3-E1 cells was examined by Western blotting analysis. Then the changes of VDR mRNA and protein in MC3T3-E1 cells were detected after the cells were treated with MAPKs inhibitors and 17β-estrodiaL Results VDR mRNA and protein were upregulated in MC3T3-E1 cells after treatment with 17β-estrodial for 72 h. ERK/ MAPK signal in MC3T3-E1 cells was activated within 15 min after treatment with 17β-estrodial and the activation remained for 60 min; but it did not activate JNK and p38 MAPK pathways. 17β-estrodial-induced VDR upregulation in MC3T3-E1 cells could be partly inhibited by ERK/MAPK inhibitor U0126. Conclusion 17β-estrodial can upregulate VDR expression in osteoblasts and can rapidly activate MAPK signal pathway, which is involved in the estrogen-induced upregulation of VDR.

Fatores genéticos que modulam concentrações de chumbo no organismo / Genetic factors modulate lead concentrations in the organism

O chumbo (Pb) é um metal pesado muito tóxico, mesmo em baixas concentrações. Ainda não foi possível estabelecer uma concentração considerada "segura" para exposições. A toxicidade ao metal é atribuída principalmente a alterações enzimáticas, como a inibição da enzima delta aminolevulínico desidratase (ALAD) e à habilidade de competir com o cálcio. A absorção do chumbo se dá prinicpalmente através das vias respiratórias e gastrointestinal. Uma vez absorvido, o metal é encontrado no sangue, tecidos moles e mineralizados. Cerca de 99% do conteúdo absorvido é encontrado nos ossos, principal reservatório de chumbo. Aproximadamente 1% encontra se livre no plasma e disponível para atravessar membranas biológicas e promover os efeitos tóxicos. Apesar das medidas tomadas no sentido de diminuir as concentrações do metal na natureza, alguns indivíduos podem ser mais susceptíveis aos efeitos prejudiciais causados pela exposição ao chumbo. Fatores genéticos vem sendo estudados e associados a diferentes concentrações sanguíneas e plasmáticas do metal em indivíduos expostos...

Lead (Pb) is a highly toxic heavy metal, even at low concentrations. There is no threshold considering "safe" for lead exposure. The toxic effects are due mainly to the enzymatic changes, such as inhibition of the enzyme delta aminolevulinic dehydratase (ALAD) and the ability to compete with calcium. The primary sites for lead absorption are gastrointestinal and respiratory tract. Once absorbed, lead is found in blood, soft tissues and mineralizing systems. Approximately 99% of the total body burden of lead is found in bones, body's major storage site. Around 1% of lead in blood is in plasma, representing the labile and biologically active lead fraction, able to pass the cells membranes and cause toxic effects. Despite the measures taken to reduce the concentrations of metal in nature, some individuals may be more susceptible to adverse effects caused by exposure to lead. Genetic factors has been studied and associated to differences among blood and plasma lead concentrations in subjects exposure. Subjects with different genotypes has proved lower or higher blood concentrations and plasma Pb...