Study on the effects of different vitamin A levels on thyroid cell apoptosis and related gene expression of mice taking excessive iodine
10.3760/cma.j.issn.1000-4955.2009.03.007
- VernacularTitle:维生素A对碘过量小鼠甲状腺细胞凋亡相关基因表达的影响
- Author:
Li-xiang, LIU
;
Hong-mei, SHEN
;
Dong-ju, QIAO
;
YUJUN
;
Ying, LI
;
Shu-bin, ZHANG
- Publication Type:Journal Article
- Keywords:
Iodine;
Vitamin A;
Apoptosis;
Fas;
FasL;
Bcl-2
- From:Chinese Journal of Endemiology
2009;28(3):259-262
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effects of different vitamin A(VA) levels on thyroid cells apoptosis and its gene expression of mice taking excessive iodine. Methods Kunming mice were randomly divided into 6 groups according to body weight 3 weeks after born: normal control(NI) group, high iodine(HI) group, low vitamin (LVA) group, high iodine plus low vitamin A(HI+LVA) group, high iodine plus vitamin A1 (HI+VA1) group, high iodine plus vitamin A2(HI+VA2) group. The VA was given in food(4000,4000,0,0,8000,16 000 U/kg), and the iodine was given as potassium iodate in water (I-:50,3000,50,3000,3000,3000 μg/L). The apoptosis was tested using in situ end labehng(TUNEL) method. Reverse transcription polymerase chain reaction (RT-PCR) were used to measure the level of mRNA of apoptosis gene(Fas, FasL, Bcl-2) in tissues. Results Apoptotic index measured by TUNEL method was rising along with the mice age. Compared to NI group[(14.09±5.68)%], apoptotic index was significantly increased in HI[(20.91±9.57)%], HI+LVA[(20.29±9.90)%]and HI+VA2 [(19.51±8.25)%]groups in the three months(P < 0.05). Compared to NI group[(16.80±9.90)%], apoptotic index was significantly increased(P < 0.05) in HI[(23.22±8.58)%],LVA[(22.56±6.17)%],HI+LVA [(25.99±9.62)%],HI+VA1 [(21.65±7.74)%]groups in the six months. Compared with the NI group(Fas: 1.29±0.25,1.27±0.26; FasL: 1.60±0.13,1.65±0.13), the mRNA levels of Fas and FasL in HI group(Fas: 1.57±0.36,1.49±0.35; FasL: 1.85±0.46,1.84±0.32) were increased, but the differences were not remarkable(P > 0.05) in the three and six months. Compared with the HI group, the mRNA levels of Fas in HI+ VA1, HI+VA2(1.33±0.35, 1.30±0.26) groups were decreased to the level in NI group in the six months. The mRNA levels of Fas and FasL were not different (P > 0.05) between HI+LVA(I.60±0.27,1.88±0.46) and HI groups in the three months. The mRNA levels of Bcl-2 were not remarkably differences in the three months (1.05±0.19,0.96±0.33,0.95±0.26,1.18±0.27,1.10±0.19,0.98±0.36, all P > 0.05), and in the six months (1.35±0.28,1.60±0.25,1.48±0.18,1.71±0.26,1.66±0.29,1.56±0.35, all P > 0.05). Conclusions Excessive iodine can cause thyroid cells apoptosis in mice. Supplementation of suitable amount of VA can regulate the levels of the apoptosis-related genes expression, and partly antagonize the apoptosis caused by high iodine.
