RESUMO
<p><b>BACKGROUND</b>High fluoride exposure can result in dental fluorosis. Fluoride and iodine are coexistent in the drinking water of areas in China and may affect the prevalence of dental fluorosis and osteogenesis. The aim of this study was to investigate the relationship between serum calciotropic hormone level, and dental fluorisis in children exposed to different concentrations of fluoride and iodine in drinking water.</p><p><b>METHODS</b>A pilot study was conducted in three villages located in the Kaifeng and Tongxu counties of Henan Province, China in 2006. Children aged 8 to 12 years, born and raised in the three villages were recruited. The fluoride levels in the samples of urine from these children were detected by fluoride ion selective electrode. Calcitonin and osteocalcin levels in the serum, and serum calcium were measured by radioimmunassay and flame atomic absorption spectrometry, respectively.</p><p><b>RESULTS</b>Fluoride levels in urine were significantly lower in children from control area (CA) as compared with those from the high fluoride & iodine areas (HFIA) and the high fluoride area (HFA) (P < 0.05 respectively), and no statistically significant difference was found between the children from HFIA and HFA. Additionally, calcitonin levels in the serum were significantly lower in children from CA and HFA as compared with that from HFIA (P < 0.05 respectively), and osteocalcin levels in the serum was lower in children from CA than those from HFIA (P < 0.05). No statistically significant difference in serum osteocalcin concentrations was found between children from HFA and HFIA.</p><p><b>CONCLUSION</b>This study provides an evidence that iodine exposure may modify the serum calciotropic hormone levels related to fluorine exposure.</p>
Assuntos
Criança , Feminino , Humanos , Masculino , Calcitonina , Sangue , Fluoretos , Fluorose Dentária , Epidemiologia , Iodo , Osteocalcina , Sangue , Projetos Piloto , Prevalência , Abastecimento de ÁguaRESUMO
Objectives To explore the relationship between polymorphism in estrogen receptor alpha (ERα)gene Xba I and child dental fluorosis.Methods Qiulou township of Kaifeng and Sunying township of Tongxu counties of Henan province were chosen as the investigation spots in 2006.An area of water drinking endemic fluorosis(high fluoride area)and a non-endemic area(control area)were chosen in every spot,where dental fluorosis of children aged 8 to 12 years old were examined and diagnosed by using the Dean method.The children in the high fluoride areas were divided into dental fluorosis group and control group of the endemic areas according to dental fluorosis status,and the children in the control areas as control gruop of non-endemic areas.The Xba I polymorphism in the ERα gene was genotyped using the PCR-RFLP procedure.The fluoride levels in the urine samples from the three groups were detected by fluoride ion selective electrode and over standard rate of the urine was counted.Results The prevalence rate of dental fluorosis in high fluoride areas was 51.7%(74/143)and the community fluorosis index was 1.310.No dental fluorosis case was checked out in the control and the community fluorosis index was 0.021.The over standard rate of urine fluoride in dental fluorosis group[84.6%(121/143)]was significantly higher than that of control in non-endemic area[9.6%(9/94);χ2=125.95,P<0.01].The frequency distribution of ERα Xba I genotype was XX 6.8%(5/74),xx 36.5%(27/74),xx 56.8%(42/74)in dental fluorosis group;XX 15.9%(11/69),Xx 37.7%(26/69),xx 46.4%(32/69)in the eontrol of the endemic areas;XX 14.9%(14/94),Xx 43.6%(41/94),xx 41.5%(39/94)in children from the control in non-endemic area,respectively.No significant difference was found among the three groups(χ2= 3.450, P > 0.05). Allele frequency of ERα Xba I genotypes was X 22.7%(30/132), x 77.3%(102/132) in dental fluorosis group and X 35.5%(39/110),x 64.5% (71/110) in the control in endemic area when urine fluorosis of children was exceeding standard and significant difference was found in this two groups(χ2 = 4.768, P < 0.05; OR = 0.535,95% CI:0.305 - 0.941). Conclusion Children who carried X allele frequency of ERα Xba I genotypes have a lower risk of dental fluorosis when children with high-loaded fluoride status.
RESUMO
Objectives To investigate the relationship between fluorosis polymorphisms in collagen type Ⅰ alpha 2 (COL1A2) and osteocalcin (OC) gene, and serum calciotropic hormone levels. Methods The children between 8 and 12 years of age in Kaifeng and Tongxu cities of Henan Province were chosen to be the object of observation. Accoding to situation of dental fluorosis, they were divided into three groups: dental fluorosis group, non-dental fluorosis group from high fluoride areas, and control group form the control areas. The Pvu Ⅱ and Rsa Ⅰ markers of COL1A2 gene as well as HindⅢ marker of OC gene were genotyped by PCR-RFLP procedure. Calcitonin and osteocalcin levels in serum were measured using radioimmunassays. Results The frequency distribution of COL1A2 PvuⅡ genotype was pp 49.3%(37/75), Pp 32.0%(24/75), PP 18.7%(14/75) in children with fluorosis; pp 43.5% (30/69), Pp 52.2% (36/69), PP 4.3%(3/69) in children without fluorosis from high fluoride areas; and pp 43.8% (42/96), Pp 40.6% (39/96), PP 15.6% (15/96) in the children without fluorosis from control areas respectively. Childrens with the homozygous genotype PP of COL1A2 Pvu Ⅱ had a significantly increased risk of dental fluorosis(OR=4.85, 95%CI: 1.22-19.32) compared to children with the homozygous genotype pp in anendemic fluorosis area. The frequency distribution of COLIA2 Rsa Ⅰ genotype was rr 50.7% (38/75), Rr 36.0% (27/75), RR 13.3%(10/75) in children with fluorosis; rr 46.4%(32/69), Rr 46.4%(32/69), RR 7.2%(5/69) in children without fluorosis from high fluoride areas, and rr 45.8% (44/96), Rr 45.8% (44/96), RR 8.3% (8/96) in the children without fluorosis from control areas respectively. There were no significant differences in the three groups (P>0.05). The frequency distribution of OC Hind Ⅲ genotype was hh 48.0% (36/75), Hh 34.7% (26/75), HH 17.3% (13/75) in children with fluorosis; hh 43.5% (30/69), Hh 43.5% (30/69), HH 13.0% (9/69) in children without fluorosis from high fluoride areas, and hh 47.9%(46/96), Hh 40.6%(39/96), HH 11.5%(11/96) in children without fluorosis from control areas respectively. There were no significant differences in the three groups (P>0.05). Additionally, fluoride levels in urine and OC levels inserum were found to be significantly lower in controls from non-endemic areas compared to cases(P<0.05). However, the differences in urine fluoride and serum OC levels were not observed when cases were compared to controls from high fluoride areas(P>0.05). Conehlsions This study provides the evidence of an association between polymorphisms in the COL1A2 gene with dental fluorosis in populations exposed to high fluoride. There were no correlation between OC Hind Ⅲ genotype and the dental fluorosis.