Implication of type 3 deiodinase induction in zebrafish fin regeneration

Thyroid hormones are critical determinants of cellular differentiation. We used the zebrafish model to evaluate the involvement of thyroid hormones in regeneration processes after caudal fin amputation. We examined early events following fin amputation, i.e., blastema formation and nerve repair by growth cone formation. Here, we show that the abolition of thyroid gland activity by methimazole treatment had no effect on blastema formation, but slowed growth cone formation of the lateral line. Conversely, the addition of exogenous thyroid hormones enhanced growth cone formation without affecting blastema formation. However, amputation triggered a strong induction in the blastema of type 3 deiodinase mRNA and enzymatic activity, which degrades thyroid hormone (TH). We therefore blocked deiodinase activity with iopanoic acid (IOP) and saw a reduction in blastema formation, suggesting that local degradation of TH is permissive for cell proliferation in the blastema. The effect of IOP on the blastema required endogenous or exogenous TH. Our findings support a model in which local degradation of TH by type 3 deiodinase is permissive for epimorphic regeneration.     

氯硝柳胺对斑马鱼幼鱼甲状腺内分泌系统的影响

目的　研究灭螺药氯硝柳胺对斑马鱼幼鱼甲状腺内分泌系统的干扰效应。方法　将受精2 h内的斑马鱼胚胎分别暴露于浓度为0、5、10、20、40 μg/L和80 μg/L的氯硝柳胺 120 h,观察不同暴露浓度下斑马鱼胚胎/幼鱼体重、胚胎孵化率、畸形率和存活率等指标;同时检测鱼体内四碘甲状腺原氨酸 （T4） 和三碘甲状腺原氨酸 （T3）水平,并采用荧光定量 PCR法检测与甲状腺激素调节相关的两个重要基因tshβ和ttr表达情况。结果　暴露于不同浓度氯硝柳胺后,各组斑马鱼幼鱼孵化率（F = 0.947, P = 0.924）和体重（F = 1.042, P = 0.409）差异无统计学意义,存活率（F = 9.309, P = 0.005）和畸形率（F = 14.900, P = 0.001）差异有统计学意义;与对照组相比,较高浓度的氯硝柳胺暴露(40 μg/L和80 μg/L)可显著降低斑马鱼幼鱼存活率 （P均 < 0.05）,并显著增加斑马鱼幼鱼畸形率 （P均 < 0.05）。 随着氯硝柳胺暴露浓度的增加, 斑马鱼幼鱼体内T4含量增加 （R2 = 0.927, F = 6.858, P = 0.003）、T3含量减少 （R2 = 0.925, F = 8.212, P = 0.001）,tshβ基因表达水平上调 （R2 = 0.840, F = 9.032, P = 0.002）、ttr基因表达水平下调 （R2 = 0.952, F = 9.130, P = 0.002）。结论　环境相关浓度的氯硝柳胺暴露可对斑马鱼幼鱼甲状腺内分泌系统造成干扰。     

Combined antisense knockdown of type 1 and type 2 iodothyronine deiodinases disrupts embryonic development in zebrafish (Danio rerio)

Thyroid hormones (THs) are important regulators of gene expression during vertebrate development. In teleosts, early embryos rely on the maternal TH deposit in the egg yolk, consisting predominantly of T₄. Activation of T₄ to T₃ by iodothyronine deiodinases (Ds) may therefore be an important factor in determining T₃-dependent development. In zebrafish, both Ds capable of T₃ production, D1 and D2, are first expressed very early during embryonic development. We sought to determine their relative importance for zebrafish embryonic development by inhibiting their expression via antisense oligonucleotides against D1 and D2, and by a combined knockdown of both deiodinases. The impact of these treatments on the rate of embryonic development was estimated via three morphological indices: otic vesicle length, head-trunk angle and pigmentation index. Knockdown of D1 alone seemed not to affect developmental progression. In contrast, D2 knockdown resulted in a clear developmental delay in all parameters scored, suggesting that D2 is the major contributor to TH activation in developing zebrafish embryos. Importantly, combined knockdown of D1 and D2 caused not only a more pronounced developmental delay than D2 knockdown alone but also the appearance of dysmorphologies in a substantial minority of treated embryos. This shows that although D1 may not be essential in euthyroid conditions, it may be crucial under depleted thyroid status as is the case when T₃ production by D2 is inhibited. These results indicate that zebrafish embryos are dependent on T₄ uptake and its subsequent activation to T₃, and suggest that substantial inhibition of embryonic T₄ to T₃ conversion reduces intracellular T₃ availability below the threshold level necessary for normal development.     

甲状腺激素对慢性心力衰竭患者外周血淋巴细胞β肾上腺素能受体密度的影响

目的 :探讨甲状腺激素 (TH)对慢性充血性心力衰竭 (CHF)患者外周血淋巴细胞 β肾上腺素能受体(β受体 )密度的影响。 方法 :2 8例扩张型心肌病 (DCM)及特发性心肌病 (ICM)所致的CHF患者随机分为A及B组 (各 14例 ) ,B组在A组常规抗心力衰竭治疗基础上加服左甲状腺激素钠 (优甲乐 5 0 ,L T50 ) 1个月 ,治疗前后 ,采用放射免疫法测定血清TH水平、同位素放射配基法测定外周血淋巴细胞 β受体密度 ,并与 8例正常人对照。 结果 :CHF患者淋巴细胞 β受体及血清TH密度低于对照者 ,治疗 1个月后 ,B组较A组血清TH水平明显增高 (P<0 .0 1) ,外周血淋巴细胞 β受体增加 (P <0 .0 5 ) ,外周血淋巴细胞 β受体变化与血清TH水平呈正相关。 结论 :TH增加DCM和ICM所致CHF患者血清TH水平 ,上调其外周血淋巴细胞 β受体密度     

性激素周期性变化对哮喘发作的影响

目的 :探讨女性哮喘患者月经周期中性激素水平对哮喘发作的影响。方法 :选择女性支气管哮喘患者 40例分为 2组 ,A组为月经期哮喘发作或原有症状加重者 2 0例 ,B组为月经期无哮喘发作或原有症状无变化者 2 0例 ,健康工作人员 2 0例作为对照组C组。各组观察对象均于月经期及经后 1周测定雌二醇 (E2 )、孕酮 (P)、血栓素B2 (TXB2 )、6 酮 前列腺素F1a(6 k PGF1a)。结果 :A组月经期E2 、P最低水平时 ,呼气峰流速 (PEF)波动率 >2 0 % ,经后E2 、P恢复正常时PEF波动率 <2 0 %。A组经期TXB2明显高于经后期 ,经期 6 k PGF1a低于经后期。A组经期E2 、P、TXB2 、6 k PGF1a与B组、C组同期相应指标比较均有明显差异。B组与C组经期及经后 1周PEF波动率均小于 2 0 % ,2组月经期E2 、P、6 k PGF1a相比均无明显差异 (P >0 .0 5 ) ,经期后TXB2 有差异 ,(P <0 0 5 )。结论 :哮喘患者月经前后E2 、P的波动幅度与哮喘发作的程度有明显关系。     

绝经后心肌梗死患者性激素与脂代谢关系的临床研究

目的:探讨绝经后心肌梗死（MI）患者性激素（SH）与脂代谢之间的关系。方法:利用放免法、免疫酶法、酶法分别检测绝经后妇女MI组（30例）和绝经后妇女对照组（30例）血中雌二醇（E2）、孕酮（P）、睾酮（T）、脂蛋白（a）[Lp（a）]、甘油三酯（TG）、总胆固醇（TC）、高密度脂蛋白胆固醇（HDL-C）、低密度脂蛋白胆固醇（LDL-C）水平。结果:与绝经后妇女对照组相比,绝经后MI组E2、E2/P、E2/T、HDL-C水平显著降低（100.35±41.26pmol/L:148.38±46.44pmol/L,P<0.001,90.52±65·48:149.75±116.74,P<0.05,104.52±64.24:154.22±111.34,P<0.05,0.95±0.30mmol/L:1.12±0.43mmol/L,P<0.05）,Lp（a）、LDL-C、TG、TC水平明显升高（21.31±17.93 mg/dl:13.52±13.04mg/dl,P<0.05.2.98±1.04mmol/L:2.15±1.19mmol/L,P<0.05,1.63±1.44mmol/L:1.13±0.55mmol/L,P<0.05,4.23±0.94mmol/L:3.50±1.36mmol/L,P<0.05）,E2与Lp（a）、LDL-C均呈负相关（r=-0.373,P<0.05,r=-0.635,P<0.01）,与HDL-C呈正相关（r=0.378,P<0.05）.结论:绝经后MI患者存在明显的以E2。水平不足为主的性激素紊乱和脂代谢异常,脂代谢异常和E2水平不足密切相关;E2水平不足促进脂代谢异常,可能是绝经后妇女MI发生的重要原因之一。     

Plasmodium falciparum gametocyte sex ratios in symptomatic children treated with antimalarial drugs

The sex ratios of Plasmodium falciparum gametocytes, defined as the proportion of gametocytes in peripheral blood that were male, were evaluated in 1609 children with acute, symptomatic, uncomplicated malaria, pre- and post-treatment with various antimalarial drugs, over an 8-year period (1999-2006) in an endemic area of southwest Nigeria. Gametocyte carriage on presentation was 10% (162 children). In 162 children in whom 5797 gametocytes were sexed on presentation, the weighted mean sex ratio was 0.18 (95% confidence interval 0.13-0.25). Following therapy, in 446 children in whom 38,519 gametocytes were sexed, the weighted mean sex ratio was 0.38 (95% CI 0.33-0.43) on day 3 and 0.70 (95% CI 0.63-0.75) (P < 0.000001) by day 7 after therapy commenced. Non-artemisinin monotherapy significantly increased sex ratio producing a male-biased ratio, but artemisinin combination therapy significantly reduced the sex ratio producing a female biased ratio. Pre-treatment sex ratio correlated negatively with haematocrit (r = −0.229, P = 0.003) or gametocytaemia (r = −0.435, P < 0.0001) but not with other clinical or parasitological parameters. The ratio of the sex-specific half lives male:female, the ‘gametocyte maleness index’ (GMI), was >1 with non-artemisinin monotherapy but <1 with artesunate and artemisinin-based combinations. In a multiple regression model, anaemia, low gametocytaemia, and enrolment before 2004 were independent predictors of a male-biased sex ratio pre-treatment. A pre-treatment haematocrit <25%, enrolment before 2004 and treatment with non-artemisinin monotherapy were independent predictors of a male-biased sex ratio 7 days postinitiation of therapy. These findings may have implications for malaria management efforts in sub-Saharan Africa.     

系统性红斑狼疮患者血清泌乳素与性激素水平关系的探讨

探讨系统性红斑狼疮患者血清泌乳素与性激素水平的关系。方法检测３１例ＳＬＥ患者ＰＲＬ，雌二醇及睾酮水平。结果ＳＬＥ患者平均ＰＲＬ水平较对照组明显升高，以活动期患者升高更为显著，同时活动期者Ｅ２水平较对照组升高，结论ＰＲＬ与ＳＬＥ的发病与病情活动密切相关，可能与雌激素分泌异常有关，而雄激素有维护免疫系统的正常功能。     

系统性红斑狼疮患者血清性激素水平的研究

目的探讨性激素在系统性红斑狼疮(SLE)发病及病程中的作用。方法测定33例SLE患者血清雌二醇(E2)、孕酮(P)、睾酮(T)、黄体生成素(LH)、卵泡刺激素(FSH)、泌乳素(PRL)的水平。对照组采用年龄、性别和卵巢周期与病例组1:1配对的原则。结果SLE整体组及活动组,PRL均显著升高(P<0.01),LH与T均显著降低(P<0.01)。FSH与LH,LH与PRL存在高度相关性(P<0.01或0.05)。FSH和T对SLE活动性评分的价值最大。结论SLE患者血清中LH与T降低与病情活动有关;对SLE活动评分最有价值的性激素为FSH和T。     

缺碘地区母婴分娩状态性别体重对新生儿TSH水平的影响

为探讨缺碘地区母婴不同分娩状态及各种生理因素对新生儿促甲状腺激素（ＴＳＨ）水平分布的影响，应用免疫放射分析（ＩＲＭＡ）测定了１５７９名新生儿脐带血ＴＳＨ水平。结果发现，ＴＳＨ值＞５ｍＵ／Ｌ者所占百分数，城镇新生儿的为１９．７％，农村的为２５．９％（Ｐ＜０．０５），女婴的为２８．１％，男婴的为２１．４％（Ｐ＜０．０１），难产的为３１．８％，足月顺产的为２３．３％（Ｐ＜０．０５）；ＴＳＨ值≥２０ｍＵ／Ｌ者所占百分数，早产的为５．３％，足月顺产的为０．４％（Ｐ＜０．０１），重度缺氧的为１２．５％，正常的为０．４％（Ｐ＜０．０１）。提示不同地区、新生儿性别、母亲分娩状态及新生儿缺氧程度对新生儿ＴＳＨ水平分布有一定影响。因此应用新生儿ＴＳＨ评价人群中碘缺乏病流行状况时应当考虑这些因素     

Production and purification of recombinant somatolactin beta and its effects on melanosome aggregation in zebrafish

A second form of somatolactin, somatolactin beta (SLbeta), was recently discovered in zebrafish (Danio rerio). This novel subtype of somatolactin is distantly related to somatolactin alpha (SLalpha) found in teleost species and is produced in a different region of the pituitary. To date, no physiological study of SLbeta has been reported. In order to study the physiological functions of SLbeta, recombinant SLbeta protein has been produced and purified. The cDNA of zebrafish SLbeta was cloned into a pET100 bacteria expression vector and His-tagged fusion proteins were produced in BL21 (DE3) Escherichia coli cells. The majority of recombinant somatolactins produced by E. coli were isolated in inclusion bodies although a small percentage of recombinant proteins (<1%) were also found in soluble form. Fusion proteins were solubilized from inclusion bodies using 6M guanidine hydrochloride. Pure recombinant somatolactins were obtained by affinity purification. The estimated molecular weight of 28 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis correlates with the molecular mass calculated from the deduced amino acid sequence of SLbeta. Thereafter, specific polyclonal antibodies against the recombinant SLbeta were developed. These antibodies recognized specifically a group of cells located in the anterior pars intermedia of the pituitary. The antibodies did not react with SLalpha, growth hormone or prolactin cells in the zebrafish pituitary glands. Furthermore, recombinant SLbeta induced melanosome aggregation in a concentration-dependent manner in skin of zebrafish scales. Significant melanosome aggregation was observed in zebrafish melanophores at a concentration of 1 microg/ml. These results, combined with previous reports demonstrate that the recombinant SLbeta proteins produced here are bioactive. The function of inducing melanosome aggregation is conserved among the somatolactin functions.     

Associations between glucose tolerance and sex hormone binding globulin among women with recent gestational diabetes mellitus

We examined cross-sectional associations of sex hormone binding globulin (SHBG) with glucose among women recent GDM (n = 55). SHBG was associated with fasting glucose levels before and after adjustment for covariates (p = 0.015), but not with 2-h glucose. We conclude SHBG should be explored in prospective studies in GDM women.     

大豆异黄酮调节前列腺增生大鼠的性激素平衡

目的　探讨大豆异黄酮对大鼠前列腺增生的影响及其机理。方法　应用丙酸睾酮诱导大鼠前列腺增生 ,观察正常对照组 (A组 )、模型组 (B组 )、低剂量大豆异黄酮组 (C组 )、中剂量大豆异黄酮组 (D组 )及高剂量大豆异黄酮组 (E组 )大鼠前列腺和性激素平衡的影响。结果　 1 C、D、E组大鼠前列腺湿重、PI、T及 E2 均显著低于 B组 (P<0 .0 5) ;2 D、E组大鼠前列腺湿重、PI、E2 / SHBG均显著低于 C组 (P<0 .0 5)。结论　大豆异黄酮可显著抑制大鼠前列腺增生 ,且呈剂量依赖性。大豆异黄酮可能是通过同时降低 T、E2的水平 ,调节大鼠的性激素平衡 ,从而起到抑制前列腺增生的作用。     

减重手术对肥胖患者性功能和性激素水平的影响

肥胖给患者带来一系列并发症,如糖尿病、肾功能不全、性功能减退等.肥胖已被确认是男性性功能障碍的危险因素,一些研究表明,肥胖男性的睾酮和性激素结合球蛋白水平下降,但雌二醇水平升高.关于肥胖对女性性功能影响的研究相对较少,对于女性性功能和肥胖之间关系的认识不一致.最近一些研究报道减重手术可提高肥胖患者的性功能,并改变性激素水平.然而对于减重手术后肥胖患者性功能和性激素的变化情况,尚未达成共识.     

血清性激素水平与老年男性骨代谢指标及骨密度的关系

目的：探讨老年男性血清性激素表达水平与骨代谢指标及骨密度之间的关系。方法：收集老年男性患者230例,年龄65～95岁,分别测定雌二醇（E2）、睾酮、游离睾酮（FT）、性激素结合球蛋白（SHBG）、脱氢表雄酮（DHEA）、骨钙素、骨碱性磷酸酶（BALP）、25-羟维生素D3及尿Ⅰ型胶原交联氨基末端肽（NTX）等指标,同时利用双能X线分别测定髋关节及腰椎（L1～L4）的骨密度,分析老年男性骨密度、骨代谢指标与血清性激素以及年龄与骨密度的相关性。结果：血清E2、FT与腰椎及髋关节的骨密度呈正相关,而睾酮、SHBG、DHEA与骨密度无关。血清E2、FT与骨代谢指标NTX、BALP呈负相关,血清E2与25-羟维生素D3呈正相关,而睾酮、SHBG、DHEA与骨代谢指标NTX、BALP无关。年龄与腰椎L1、L2、L4、L1～4及髋部骨密度呈负相关,与腰椎L3骨密度无关。结论：老年男性骨密度的变化受性激素中FT、E2表达水平的影响,而受E2的影响程度超过雄激素。血清FT及血清E2的水平可作为老年男性骨质疏松症的独立观察指标。     

Effects of dexamethasone treatment on iodothyronine deiodinase activities and on metamorphosis-related morphological changes in the axolotl (Ambystoma mexicanum)

In amphibians, there is a close interaction between the interrenal and the thyroidal axes. Hypothalamic corticotropin-releasing hormone or related peptides stimulate thyroidal activity by increasing thyrotropin synthesis and release, while corticosterone accelerates both spontaneous and thyroid hormone-induced metamorphosis. One of the mechanisms that is thought to contribute to this acceleration is a corticosterone-induced change in peripheral deiodinating activity. The present experiments were designed to investigate further the effects of glucocorticoid treatment on amphibian deiodinase activities and to explore the possible role of these effects in metamorphosis. Neotenic axolotls (Ambystoma mexicanum) were treated either acutely or chronically with dexamethasone (DEX) and changes in type II and type III iodothyronine deiodinase (D2 and D3) activities were studied in liver, kidney, and brain. In addition, gill length, tail height, and body weight were measured at regular intervals in the chronically treated animals in search of metamorphosis-related changes. A single injection of 50 microg DEX decreased hepatic D3 activity (6-48 h) while it increased D2 activity in brain (6-48 h) and to a lesser extent in kidney (24 h). These changes were accompanied by an increase in plasma T(3) levels (48 h). Samples taken during chronic treatment with 20 or 100 microg DEX showed that both hepatic D2 and D3 activities were decreased on day 26, while renal D3 activity was decreased but only in the 20 microg dose group. All other deiodinase activities were not different from those in control animals. At 25 days, all DEX-treated axolotls showed a clear reduction in gill length, tail height, and body weight, changes typical of metamorphosis. Prolongation of the treatment up to 48 days resulted in complete gill resorption by days 44-60. Although probably several mechanisms contribute to these DEX-induced metamorphic changes, the interaction with thyroid function via a sustained downregulation of hepatic D3 may be one of them.     

男性Ⅱ型糖尿病患者胰岛素敏感性与性激素结合球蛋白浓度相关性研究

以初次诊断未经治疗１９例男性ＩＩ型糖尿病患者为研究对象，以空腹血糖（ＦＰＧ）与空腹胰岛素（ＦＩＮＳ）浓度乘积的倒数作为胰岛素依赖型指数（ＩＳＩ）。分析ＩＳＩ与年龄，腰臂围比（ＷＨＲ），体重指数（ＢＭＩ），性激素结合球蛋白（ＳＨＢＧ）以及睾酮（Ｔ）的相关性，结果发现ＩＳＩ与ＳＨＢＧ呈极显著性正相关（ｒ＝０．５６，Ｐ＝０．０１）。在以ＩＳＩ为变量，以年龄，ＷＨＲ，ＢＭＩ，ＳＨＢＧ和Ｔ为自变量的逐步回归