新生早期甲状腺功能减退大鼠心肌甲状腺激素受体mRNA表达的实验研究

目的探讨新生早期甲状腺功能减退（简称甲减）对大鼠心肌发育过程中甲状腺激素受体（TR）各亚型mRNA表达的影响。方法Wistar雌鼠从怀孕15d开始每天经胃灌注1％丙硫氧嘧啶2．5ml，复制甲减仔鼠动物模型，分别于各时间点称体质量后处死仔鼠，取心脏。放射免疫分析法（RIA）动态监测各组大鼠血清FT3、FT4水平，FQ—PCR方法检测各组心肌TR各亚型mRNA的表达差异。结果与对照组比较，甲减大鼠心肌TRα1 mRNA表达量在出生后0、21、45d分别下调90％、15％、36％（tod=8．33，t21d=2．58，t45d=3．25，P〈0．05），表达峰值于生后2周延迟出现。甲减大鼠心肌TRα2 mRNA表达量在出生后0、14、21、45d分别上调22％、72％、82％、36％（t0d=3．89，t14d=11．88，t21d=13．90，t45d=6．19，P〈0．05），表达峰值于生后2周延迟出现。甲减大鼠心肌TRβ1 mRNA表达量在出生后0、14、21、45d分别下调75％、62％、68％、60％（t0d=38．96，t14d=5．22，t21d=17．23，t45d=5．43，P〈0．05），表达变化趋势与对照组一致。结论新生早期甲减大鼠心肌上TR mRNA的异常表达可能与甲减性心脏病的发病机制密切相关。     

碘诱发NOD和Balb/c小鼠甲状腺炎的实验研究

Objective To observe the different effects of iodine excess on inducing two strain mice thyroiditis. Methods NOD and Balb/c mice, each having 14 mice, were divided into NaI and control group. The mice were given 0.05% NaI water for 8 weeks in NaI group. RIA and ELISA were used respectively to detect TT4, TgAb, TPOAb and TSH level in serum. Morphology changes of thyroid and apoptosis of thyrocytes stained by immunohistochemistry were observed under light microscope. Lymphocytic proliferation of cervical lymph node and spleen to responding to Tg were detected by MTr method. Results After intake of iodine water for 8 weeks, NOD and Balb/c mice showed relative quality of thyroid in Nal group[(104.83±14.52), (155.79±20.77)mg/kg]obviously increased compared with control group[(71.80±20.42), (105.15±21.98)mg/kg, t values:-3.293,-4.429, all P< 0.01)], enlarged follicular lumen with colloid accumulation were observed in thyroid. Serum level of TT4 in Nal group [(29.52±4.42), (19.53± 2.35)nmol/L]to control group[33.40±5.38), (23.47±6.22)nmol/L]of NOD and Balb/c mice showed a decreasing tendency(t values: 1.374,1.567, all P > 0.05). TSH of Nal group showed an increasing tendency in Balb/c mice[(4.14±1.71)μg/L, compared with control [(3.55±1.41)μg/L, t values:-0.705, P > 0.05]and obviously increased in NOD mice [(6.98±0.66)μg/L, compared with control[(555±056)μg/L, t values:-3.562, P< 0.01], but no change of TgAb and TPOAb level in Nal group(1281,1364 cpm, 2.50×103, 0.14×103U/L were observed, compared with control(1297,1220 cpm, 3.17×103,0.03×103 U/L; Zvalues:-0.081,-0.703, -0.244,-1.293, all P > 0.05). In NOD mice NaI group, apoptosis of thyrocytes was more intense than Balb/c mice, obvious infiltration of lymphoeytes, disorganization and focus fibrosis was seen in thyroid. The cell amount of NaI group increased in NOD mice lymph node and spleen cells[(1.100±0.014), (1.076±0.033)]were more than that in the control group [(0.993±0.011), (1.005±0.003), t value:-11.672,-4.314, P < 0.01). Conclusions Iodine leads to enlargement of thyroid and malfunction of thyroid in Balb/c mice. Besides, NOD mice have generate inflammatory reaction in thyroid and produced sensitized lymphocytes to Tg. Iodine excess can induce NOD mice to occur autoimmune thyroiditis.     

碘缺乏对BALB/c小鼠促甲状腺激素β剪接变体基因表达的影响

目的 制备碘缺乏小鼠模型,检测促甲状腺激素(TSH)β剪接变体(TSHβ-Ⅴ)是否受循环中甲状腺激素的调节,探讨免疫系统来源的TSHβ-Ⅴ在维持甲状腺自稳态中的作用.方法 选用离乳BALB/c小鼠20只,雌雄各半.小鼠按体质量和性别随机分为2组,每组10只.对照组:饮去离子水,普通饲料喂养;低碘组:饮去离子水,低碘饲料(含碘量20 - 40μg /kg)喂养,每日碘摄入量约为0.25μg/d.3个月后处死小鼠,化学发光免疫分析法(CIA)检测小鼠血清中甲状腺激素和TSH水平,实时定量(RT)-PCR法测定小鼠骨髓、外周血、甲状腺、垂体TSHβ-Ⅴ的表达.结果 低碘组小鼠血清总甲状腺素(TT4)、游离甲状腺素(FT4)、总三碘甲腺原氨酸(TT3)、游离三碘甲腺原氨酸(FT3)[ (0.47±0.70)nmol/L、(2.41±0.28)pmol/L、(0.76±0.08 )nmol/L、(4.01±0.40) pmol/L]显著低于对照组[(55.2±3.68)nmol/L、(32.72±1.02) pmol/L、(1.10±0.06)nmol/L、(5.40±0.38 )pmol/L,t=43.81、86.04、9.81、7.51,P均＜0.01];低碘组小鼠TSH[(35.67±17.39)mU/L]明显高于对照组[(0.24±0.10)mU/L,t =-6.11、,P＜0.001];低碘组小鼠骨髓、外周血TSHβ-Ⅴ mRNA表达水平[(9.62±0.60)、(9.25±0.83)]均低于正常对照组(7.69±0.36、7.11±0.41,t=6.77、5.64,P均＜0.001);低碘组小鼠甲状腺TSHβ-Ⅴ mRNA表达(9.32±0.91)与对照组(9.12±0.62)相比较,差异无统计学意义(t=0.45,P＞0.05);在骨髓、外周血、甲状腺未检出天然型TSHβ;垂体中TSHβ-Ⅴ mRNA和天然型TSHβ表达水平(1.99±0.61、- 7.17±1.78)均高于对照组(5.75±0.98、-1.43±0.51,t=-8.02、- 7.60,P均＜0.01].结论 低碘饮食引发小鼠甲状腺功能低下,抑制骨髓和外周血TSHβ-Ⅴ mRNA的表达,提示免疫系统来源的TSHβ-Ⅴ可能具有比天然型TSHβ更重要的免疫-甲状腺调节作用.     

人骨保护素在CHO细胞内初步稳定表达

目的构建人OPG的稳定表达载体,并在DHFR-型CHO细胞内稳定表达。方法用RT-PCR的方法获得人全长OPG的编码基因,并将其克隆入载体pcDNA3.1-DHFR/CT-GFP,鉴定无误后,转染DHFR-型CHO细胞,经MTX筛选获得阳性表达OPG的细胞株。结果成功构建人OPG的稳定表达载体,并获得阳性表达OPG的细胞株。结论全长人OPG基因可以在CHO细胞内成功稳定表达,这为OPG的功能研究及临床应用奠定物质基础。     

ODF诱导骨髓细胞向破骨细胞分化

目的:研究小鼠骨髓细胞在破骨细胞分化因子(ODF)和单核巨噬细胞集落刺激因子(M-CSF)的诱导刺激下向破骨细胞诱导分化的新方法。方法:分离小鼠骨髓细胞,ODF、M-CSF诱导培养,在倒置显微镜下观察细胞形态变化,酒石酸酸性磷酸酶(T-ACP)阳性表达。结果:小鼠骨髓细胞在ODF和M-CSF作用下,表现为长梭形和圆形细胞增多,增大。体外培养6d,有多核T-ACP阳性细胞产生。结论:小鼠骨髓细胞在ODF和M-CSF共同诱导作用下分化成破骨细胞,为体外研究破骨细胞的分化发育和功能调节提供新方法。     

PDGF对人神经干细胞分化和甲状腺激素受体表达的影响

[目的]探讨血小板衍生生长因子(Platelet-derived Growth Factor,PDGF)在人神经干细胞(Human Neural Stem Cells,hNSCs)定向分化中的作用,以及在hNSCs分化过程中PDGF对甲状腺激素受体(Thyroid Hormonereceptors,TRs)的表达调控。[方法]用免疫细胞化学方法鉴定分化后的细胞类型,分别用半定量RTPCR法、 ELISA法检测不同诱导条件下hNSCs分化前后TRα1、TRα2、TRβ1在转录与翻译水平上的表达变化。 [结果]PDGF诱导hNSCs分化后NF阳性细胞约占80％;TRα1、α2、β1mRNA表达水平分别比10％胎牛血清诱导分化组上调约40％、30％、10％(P<0．05)。TRα、β蛋白质表达趋势为hNSCs>PDGF诱导分化组>血清诱导分化组(P<0．05)。[结论]PDGF能引发hNSCs向神经元分化,同时在转录与翻译水平上调hNSCs分化后TR各亚型的表达,增强甲状腺激素对中枢神经系统发育的重要调控作用。     

甲亢大鼠心肌甲状腺激素受体mRNA的表达

【目的】探讨正常与甲亢大鼠心肌甲状腺激素受体mRNA表达差异。【方法】将16只实验大鼠随机分为正常对照组和甲亢组两组,每组8只:实时荧光定量PCR(FQ-PCR)方法检测正常对照组与甲亢组大鼠心肌甲状腺激素受体各亚型mRNA表达差异。【结果】与正常大鼠心肌相比,甲亢大鼠心肌甲状腺激素受体α1 mRNA表达上调51%(t=9.17,P<0.01),甲状腺激素受体α2 mRNA表达下调58%(t=10.02,P<0.01),甲状腺激素受体β1 mRNA表达不受影响(t=0.96,P>0.05)。【结论】高甲状腺激素水平对甲状腺激素受体α1、α2、β1mRNA表达影响不一致,甲亢大鼠心肌甲状腺激素受体αmRNA的异常表达变化可能与甲亢心脏病的发病密切相关。     

碘过量和多聚肌苷酸-聚胞苷酸及甲状腺球蛋白诱发小鼠甲状腺炎对Toll样受体3表达的影响

Objective To observe the effect of iodine excess(HI),polyinosinic-polycytidylic acid[Poly(I:C),Poly]and thyroglobulin(TG)on the thyroid of mice by the expression of Toll-like receptor 3(TLR3)to reveal the functional role of TLR3 in autoimmune thyroiditis.Methods Forty-two non-obese diabetic mice,body weight (20±3)g,were divided into six groups:control group,HI group,Poly group,TG group,HI+TG group,HI+Poly group. Fed with deionized water and injected intraperitoneally with physiological saline 0.1 ml each day for a week, the mice in control group were injected with physiological saline every other day at the same dose for 1 week before they were sacrificed; HI group drank 0.05% NaI water and were injected intraperitoneally with physiological saline same as control group; Poly group drank deionized water and were injected intraperitoneally with poly 0.1 ml (1 g/L)each day of the week, then the mice were injected with Poly every other day at the same dose for 1 week before they were sacrificed; TG group drank deionized water and were injected intraperitoneally with physiological saline same as control group, immunized with 0.1 mg TG by subcutaneously injecting and the immunization was enhanced after they were fed half dose for 4 and 8 weeks separately. In HI + Poly group, the treatment was the same as HI group and Poly group; HI + TG group: the treatment was the same as HI group and TG group. Eight weeks later, mice were sacrificed and thyroids were taken to make frozen sections, Hematoxylin-Eosin (HE) staining was employed to observe the morphological change of the thyroids. The expression of TLR3 of thyroids was observed under fluorescence microscope after Immumofluorescence using TLR3 antibody and TR3-positive cells were analyzed in the thyroid density. Results HE staining showed thyroids of Poly group had no inflammation under microscope.There were different degrees of inflammatory cell infiltration in HI group and TG group. The inflammatory cell infiltration and the damage of follicular thyroid of HI + TG group and HI + Poly group were serious, and the degrees of inflammation were higher over "++". Thyroid follicular epithelial cell with TLR3 expression could be seen in Poly group and HI group, meanwhile, there were TLR3 strong positive inflammatory cells in HI group under fluorescent microscope. Using stereological analysis of TLR3-positive cell density in the thyroid, the difference between groups was statistically significant(F=7.870, P<0.01 ). TLR3-positive cell density in the thyroid of HI + Poly group was higher[ (9.287 ± 0.522)mm2] than control group[ (0.062 ± 0.025)mm2, P < 0.01] significantly, meanwhile, the density in HI + Poly group was higher than HI group [ (2.574 ± 0.257 )mm2] and Poly group[ (1.361 ± 0.148 )mm2, all P < 0.01]. The density in HI + TG group[ (4.843±0.405)mm2] was higher than HI group and TG group[(1.601 ±0.268)mm2, all P < 0.01 )]. Conclusions Excessive iodine and thyroglobulin can induce thyroiditis, and stimulate the expression of TLR3 in the thyroid follicular epithelial, Poly aggravated thyroiditis induced by iodine excess in NOD mice; TLR3 positive inflammatory cells also appeared in inflammatory region, suggesting that TLR3 is involved in the pathogenesis of autoimmune thyroiditis     

PDGF对人神经干细胞分化和甲状腺激素受体表达的影响

目的　探讨血小板衍生生长因子 (platelet-derived growth factor,PDGF)在神经干细胞 (neural stem cell,NSC)定向分化中的作用 ,以及 PDGF在 NSC分化过程中对甲状腺激素受体 (thyroid hormone receptors,TRs)表达的调控。方法　用免疫细胞化学方法鉴定分化后的细胞类型 ,分别用 RT-PCR半定量法、ELISA法检测不同诱导条件下 NSC分化前后 TR-α1 、TR-α2 、TR-β1 在转录与蛋白表达水平上的变化。结果　 PDGF诱导分化后神经丝蛋白 (neurofilament protein,NF)细胞约占 80 % ;TR-α1 、TR-α2 、TR-β1 m RNA表达水平分别比 1 0 % (体积分数 )胎牛血清诱导分化组上调约 40 %、3 0 %、1 0 % (P<0 .0 5 )。TR-α、TR-β蛋白质表达趋势为 NSC>PDGF诱导分化组 >血清诱导分化组 (P <0 .0 5 )。结论　 PDGF能引发 NSC向神经元分化 ,同时在转录与蛋白表达水平上调 NSC分化后 TR各亚型的表达 ,增强甲状腺激素对中枢神经系统发育的调控作用。     

碘过量对NOD和Balb/c鼠甲状腺TRAIL和TRAIL-sR1表达的影响

Objective To investigate the influence of iodine excess on expression of TRAIl/TRAIL-sR1 in NOD and Balb/c mice and to study the effect of TRAIl/TRAIL-sR1 on the pathogenesis of experimental autoimmune thyroiditis(EAT). Methods Both Balb/c and NOD mice were divided randomly into control and iodine excess group by feeding with water containing no NaI or 0.05% Nal. The mice were sacrificed after 8 weeks. TRAIL and TRAIL-sR1 mRNA levels were detected by RT-PCR. The function, morphology and apoptosis of thyroids were also observed by ELISA and Tunnel stain. Results Treated by HI, enlarged follicles and flattened epithelium by accumulation of colloid were found in thyroids of both NOD and Balb/c mice. But significant lymphoid cell infiltration and local fibrosis were only found in thyroids of NOD HI group. The relative weight of thyroids of NOD mice in HI group[(104.8±14.5)mg/kg]was heavier than that of control group [(71.8±20.4)mg/kg]. The level of TT4 declined in HI group[(30.77±3.59)mmol/L]compared with control group[(36.43±2.66)mmol/L], meanwhile, the level of TSH was higher in HI group[(6.98±0.66)μg/L]than that in control group [(5.55±0.56)μg/L]. The difference being statistically significant(t=7.773,-9.526,-4.458, all P < 0.05). The relative weight of thyroids of Balb/c mice of HI group[(155.8±20.8)mg/kg]also heavier than that of control group [(105.1±22.0) mg/kg]. The level of TT4 droped in HI group [(19.75±3.32) mmoL/L]was higher than that in control group[(23.46±6.21)mmoL/L], the level of TSH in HI group[(4.14±1.71)μg/L]was higher than that in control group[(3.55±1.41)μg/L], the difference being statistically significant(t=7.554,-7.239,3.140, all P< 0.05). A great deal of apoptotie ceils observed in NOD (3.97±0.91) and Balb/c mice (1.05±0.45) by Tunnel stain were greater than control groups (0.21±0.15, 0.10±0.03), the difference being statistically significant in beth of the two species(t=-7.167,-17.772, both P < 0.05). The apoptosis index of thyroid follicular epithelium in NOD was obviously higher than Balb/c(t=-7.625, P<0.05). The level of TRAIL mRNA did not remarkably change in Balb/c between control group(0.000 59±0.000 39) and HI group(0.001 24±0.000 46, t=-1.940, P>0.05), but it increased apparently in NOD mice HI group(0.018 88±0.005 77) than that of control group(0.009 61± 0.00591, t=-2.71, P<0.05). The level of the expression of TRAIL-sR1 mRNA increased in HI groups of NOD (0.000 53±0.000 15) and Balb/c mice(0.000 42±0.000 09) than that in control groups of NOD(0.000 28± 0.000 05) and Balb/c mice (0.000 17±0.000 06) and the differences were statistically significant between the two species(t=3.050,3.990, all P<0.05). The differences of the expression of TRAIL and TRAIL-sR1 mRNA between the two species were significant(t=-3.37,-4.76, all P<0.05). Conclusions Iodine excess induces colloid goiter in beth species of mice and thyroiditis in NOD mice. The increase of TRAIL and TRAIL-sR1 influenced by iodine excess is one of the molecular bases of follicular epithelium apoptosis and inflammation in thyroids. Genetic factor is a key factor in the pathogenesis of thyroiditis.