生长激素缺乏症患儿血清胰岛素样生长因子-1及其结合蛋白的变化

目的 研究血清胰岛素样生长因子1(IGF-1)、胰岛素样生长因子结合蛋白-3(IGFBP-3)浓度与生长激素缺乏症(GHD)患儿生长激素(GH)激发试验中血清GH峰值关系,为其代替GH激发试验提供依据。方法选择GHD患儿62例(男39例,女23例),为GHD组;60例健康儿童(男38例,女22例)为对照组。分别用放射免疫分析法(RIA)、免疫放射分析法(IRMA)检测两组血清IGF-1、IGFBP-3浓度,同时做GH激发试验,测定血清GH峰值,并比较其与IGF-1、IGFBP-3的关系。结果 GHD血清IGF-1、IGFBP-3均显著低于对照组(t=3.116、11.579 P均<0.01);GHD组血清IGF-1、IGFBP-3浓度与GH激发试验中GH峰值呈显著正相关(r=0.331、0.347 P均<0.01);GHD组血清IGF-1、IGFBP-3降低阳性率分别为97.58％、98.38％,与激发试验的阳性率(100％)比较无统计学意义(x~2=3.074、2.033 P均>0.05)。结论 血清IGF-1、IGFBP-3浓度的检测对诊断GHD有重要意义;检测血清IGF-1、IGFBP-3浓度可替代GH激发试验。     

先天性心脏病患儿营养不良与生长激素-胰岛素样生长因子轴的关系

目的探讨先天性心脏病（CHD）患儿营养不良与生长激素-胰岛素样生长因子（GH-IGF）轴的关系。方法依据有无发绀及心力衰竭,将50例CHD患儿分为发绀组13例、非发绀组37例;非发绀组又分为2个亚组：心力衰竭组25例、无心力衰竭组12例。20例健康儿童作为健康对照组,通过测定各组儿童血总蛋白、清蛋白及测量身高、体质量来评价其营养状况;采用免疫放射分析方法来检测血IGF-Ⅰ、胰岛素样生长因子结合蛋白-3（IGFBP-3）及生长激素结合蛋白（GHBP）,并进行比较。结果CHD患儿急、慢性营养不良的发生率分别为62%和28%,急性营养不良的发生率发绀组与非发绀组相似（P=0.105）;慢性营养不良的发生率发绀组高于非发绀组（P=0.006）;各组CHD患儿血清IGF-Ⅰ、IGFBP-3水平均下降,其中发绀组及心力衰竭组下降更为显著;发绀组及心力衰竭组患儿血GHBP水平下降。结论CHD患儿血清IGF-Ⅰ和IGFBP-3水平下降,考虑与生长激素受体（GHR）有关,GHR下调可能是GH抵抗或不敏感的分子机制之一,而GH抵抗或不敏感是CHD患儿发生急、慢性营养不良的原因之一。     

血清胰岛素样生长因子-1、胰岛素样生长因子结合蛋白-3在矮小症儿童诊断和疗效判断中的价值

目的探讨胰岛素样生长因子-1（IGF-1）及其结合蛋白-3（IGFBP-3）在矮小症儿童诊断及疗效判断中的价值。方法1．对124例青春发育前矮小症患儿用精氨酸激发试验和可乐定激发试验检测其血清生长激素（GH）水平，并根据患儿GH峰值分为生长激素缺乏组（GHD组，40例）、特发性矮小组（1SS组，84例）。选取20例健康儿童作为健康对照组。对所有儿童采用酶联免疫吸附法检测血清IGF—1和IGFBP-3。对GHD组、ISS组和健康对照组儿童血清IGF-1和IGFBP-3水平进行两两比较。2．对15例GHD和30例ISS患儿予国产重组人生长激素（rhGH）0．1IU／（kg&#183;d）治疗6个月，于治疗前及治疗6个月分别测定其身高、体质量、骨龄及血清IGF-1、IGFBP-3，并进行治疗前后的对照。结果1．GHD组和ISS组患儿血清IGF-1和IGFBP-3水平明显低于健康对照组（Pa〈0．01），GHD组与ISS组患儿血清IGF-1和IGFBP-3水平比较均有显著差异（Pa〈0．01），GHD组患儿治疗前后血清IGF-1、IGFBP-3比较有显著差异（Pa〈0．01）；诊断GHD，IGF-1的特异性为67．8％，敏感性为75％；IGFBP-3的特异性为88％，敏感性为85％。2．rhGH治疗后身高增长速度明显加快，血清IGF-1、IGFBP-3水平显著升高；治疗前血清IGF-1与治疗6个月生长速度呈显著负相关（r=-0．78P〈0．01）；治疗6个月后IGF-1的变化与治疗后生长速度呈显著正相关（r=0．82P〈0．01）。结论IGF-1、IGFBP-3可用于儿童矮小症的诊断及疗效评价。     

6个月内婴儿血清生长激素、胰岛素样生长因子-1、胰岛素样生长因子结合蛋白-3变化与体格发育的关系

目的 探讨6个月内婴儿血清生长激素(GH)、胰岛素样生长因子-1(IGF-1)、胰岛素样生长因子结合蛋白-3(IGFBP-3)水平变化与体格发育值的关系.方法 对85例低出生体质量儿(LBWI)及29例足月适于胎龄儿于生后3 d、3个月、6个月时进行放射免疫法检测血清GH、IGF-1、IGFBP-3,同时测量婴儿体质量、身长、头围、胸围.结果 生后3 d小于胎龄儿的体格发育值和血清GH、IGF-1、IGFBP-3均分别低于适于胎龄儿(P均＜0.05),早产儿均小于足月适于胎龄儿(P＜0.05).3、6个月时LBWI的体格发育值和血清GH、IGF-1、IGFBP-3浓度均低于足月适于胎龄儿(P＜0.05).生后3 d、3个月、6个月时各体格发育值与各激素浓度均呈正相关.结论 新生儿血清GH、IGF-1、IGFBP-3浓度水平与胎儿生长发育有密切关系.LBWI生后6个月血清GH、IGF-1、IGFBP-3仍存在相对低水平状态,体格发育值仍落后于正常足月儿.     

矮小儿童下丘脑-垂体及其胰岛素样生长因子轴功能检查的意义

目的检测矮小儿童下丘脑-垂体及其胰岛素样生长因子(IGF-1)生长轴(GHRH-GH-IGF-1)功能,了解矮小儿童的发病因素及确定下丘脑-垂体及其IGF轴功能缺陷病因分类。方法矮小儿童30例。用统一印制的矮小儿童表格记录其临床特征。对矮小儿童进行甲状腺功能测定;用胰岛素 左旋多巴行生长激素(GH)刺激试验;放射免疫法测定血清IGF-1和血清胰岛素样生长因子结合蛋白-3(IGFBP-3)水平;同时行患儿骨龄、垂体增强MRI扫描、染色体核型分析、性激素测定。根据矮小症诊断标准和2004年Rosenfeld RG和GHRH-GH-IGF-1轴缺陷不同,将矮小儿童进行病因定位和分类。结果矮小儿童30例中,下丘脑-垂体及其IGF轴功能缺陷12例,占40%,其中肯定生长激素缺乏(GHD)4例,怀疑生长激素不敏感综合征2例,可疑GHD 6例。Turner′s综合征2例,占6.67%;体质性青春期延迟2例,占6.67%;特发性矮小14例,占46.6%。磁共振发现垂体微腺瘤2例;垂体发育不良12例。结论1.矮小儿童所占比例最大的为特发性矮小,其次为下丘脑-垂体及其IGF轴功能缺陷。2.IGF-1水平和IGFBP-3水平与生长激素刺激试验测定生长激素水平不一致,考虑存在生长激素抵抗和受体缺陷。3.矮小儿童可能存在先天性垂体发育异常,致使垂体分泌生长激素不足。     

甲状腺功能减退症患儿血清生长激素、胰岛素样生长因子-Ⅰ、胰岛素样生长因子结合蛋白-3水平的变化

目的通过监测甲状腺功能减退症患儿生长激素(GH)、胰岛素样生长因子-Ⅰ(IGF-Ⅰ)、胰岛素样生长因子结合蛋白-3(IGFBP-3)水平变化,探讨甲状腺功能减退症患儿GH-IGF轴与甲状腺素的变化规律。方法对56例甲状腺功能减退症(14例先天性甲状腺功能减退症和32例桥本病)患儿治疗前后血GH、IGF-Ⅰ、IGFBP-3水平和50例健康儿童血GH、IGF-Ⅰ、IGFBP-3水平进行监测。结果先天性甲状腺功能减退症新生儿9例患儿IGF-Ⅰ、IGFBP-3水平显著降低,经治疗后甲状腺功能逐渐恢复正常;5例先天性甲状腺功能减退症患儿和32例桥本病患儿无显著变化。结论先天性甲状腺功能减退症患儿存在GH-IGF轴功能紊乱,是导致身材矮小的重要原因,早期予甲状腺素治疗有利于维持患儿正常生长发育。     

生长激素受体基因异常及多态性与特发性矮小的关系研究进展

随着促生长激素释放激素-生长激素-胰岛素样生长因子(GHRH-GH-IGF-1)轴和基因学研究的深入,生长激素受体基因(GHR基因)的突变及其核苷酸多态性与特发性矮小(ISS)的关系逐渐明了.GHR基因异常多发生在生长激素受体(GHR)蛋白的胞外区,可引起细胞内信号转导障碍,导致GHR蛋白功能及表达部分缺失,生长激素不能完全发挥作用或部分不敏感,从而可能发生ISS; GHR基因单核苷酸多态性(SNP),尤其是外显子Ex3多态性与ISS易感性有关.此外,GHR基因异常及SNP与ISS中IGF-1、生长激素结合蛋白血清水平及重组人生长激素治疗效果密切相关.深入研究ISS中GHR候选基因的筛查、蛋白功能表达及SNP分析,有利于提高ISS的遗传诊断水平,对明确ISS的病因及指导临床治疗具有重要意义.     

胰岛素样生长因子-1受体基因与特发性矮小相关性研究进展

生长激素-胰岛素样生长因子(GH-IGF)轴是调节儿童生长发育中最重要的神经内分泌轴.胰岛素样生长因子-1受体( IGF-1 R)是调节该轴的激素受体级联反应的效应分子,它的分子结构或功能异常,将影响靶基因IGF-1与其结合,从而引起生长障碍,可能与特发性矮小(ISS)发生有一定关系.国内外尚无IGF-1R基因与ISS的研究,为探讨其与ISS的关系,现就近年来有关IGF-1 R与人体生长障碍的研究作简要综述.     

新生儿血清瘦素、生长激素、胰岛素样生长因子-1、胰岛素样生长因子结合蛋白-3水平与宫内发育的关系

目的 探讨瘦素(leptin)、生长激素(GH)、胰岛素样生长因子-1(IGF-1)、胰岛素样生长因子结合蛋白-3(IGFBP-3)在不同宫内发育状况胎儿中的变化,及对胎儿生长发育调控的作用.方法 2004年1月-2006年6月出生早产小于胎龄儿(A组)30例,早产适于胎龄儿(B组)36例,足月小于胎龄儿(C组)32例,足月适于胎龄儿(D组)37例.生后24 h内抽取患儿静脉血,用放射免疫法(RIA)检测其血清leptin、GH、IGF-1、IGFBP-3水平,组间比较采用及多元回归相关分析.结果 各组新生儿血清leptin、GH、IGF-1、IGFBP-3水平均存在明显差异(Pa<0.05,0.01),各指标基本呈C、A、B、D组次序由低到高,但A组IGF-1与C组差异无统计学意义(P>0.05);在A、B和C组,出生体质量与leptin、IGF-1、IGFBP-3呈正相关(Pa<0.01),而D组出生体质量与IGF-1呈正相关(P<0.01),与其他激素无相关性.结论 leptin、IGF-1、IGFBP-3参与宫内发育迟缓儿和早产儿宫内生长发育的调控.IGF-1在早产适于胎龄儿的宫内生长发育中也起调控作用,而leptin、GH、IGFBP-3均不是足月适于胎龄儿生长发育的主要调节因素.     

短期生长激素治疗对营养不良矮小儿童血糖、甲状腺功能、胰岛素生长因子-Ⅰ、胰岛素生长因子结合蛋白-3的影响

目的探讨重组人生长激素(rhGH)短期治疗对营养不良矮小儿童空腹血糖(GLU)、甲状腺功能(TF)、胰岛素生长因子-Ⅰ(IGF-Ⅰ)、胰岛素生长因子结合蛋白-3(IGFBP-3)的影响。方法选取16例年龄2～12岁、符合营养不良矮小诊断的患儿。采用rhGH治疗3个月。分别在治疗前、治疗1和3个月,取患儿清晨空腹血,测定GLU、三碘甲状腺原氨酸(T3)、甲状腺素(T4)、促甲状腺素(TSH)、IGF-Ⅰ、IGFBP-3水平。采用方差分析比较3个时间点测量指标的均数。结果营养不良矮小儿童经rhGH治疗1和3个月后,GLU、T3、T4、TSH、IGFBP-3均无明显变化(Pa>0.05),IGF-Ⅰ明显高于治疗前,且有统计学意义(P<0.05)。结论rhGH短期治疗能使营养不良性矮小儿童的IGF-Ⅰ升高,且不影响GLU、TF。     

Fetal growth regulation and intrauterine growth retardation

Gestational age and neonatal anthropometric parameters are currently used to evaluate fetal growth and are predictive factors of perinatal and postnatal morbidity and mortality. We performed a retrospective analysis of neonatal anthropometric parameters (weight, vertex-heel length and head circumference) in 1,470 live preterm neonates born between 1997 and 2002 and a prospective analysis of the same parameters in 1,786 live newborns of both sexes born in 2001 and 2002, products of single 37-42 week uncomplicated pregnancies in healthy Spanish Caucasian mothers. A progressive increase in these parameters with gestational age and sexual dimorphism were observed from the 30th week of gestational age onwards, with statistically-significant differences (p<0.05) at 38-42 weeks of gestational age. An increase in weight and length values in relation to previous Spanish studies was also documented in preterm newborns. It is estimated that 10-15% of children born small for gestational age (SGA) do not experience catch-up growth by the age of 3 years and may have short stature in adulthood. Preliminary data of a cross-sectional study on spontaneous growth in boys and girls born SGA without postnatal catch-up growth show that their +2 SD values of height are similar to -2 SD values of our normal control population of children born with adequate weight and length for gestational age (AGE). However, weight +2 SD values are similar to mean values of control children born AGE. In summary, our data show sexual dimorphism in neonatal anthropometric growth parameters and that these parameters change with time and may be updated. In addition children born SGA without postnatal catch-up are shorter and have higher weight than age-, height- and sex-matched controls born AGE.     

Nutrition-induced catch-up growth at the growth plate

The effect of 40% food restriction (FR) and replenishment on the growth hormone (GH) and insulin-like growth factor-I (IGF-I) axis in the epiphyseal growth plate (EGP) was examined in a mouse model. Changes in RNA and protein levels were evaluated with real time PCR and immunohistochemistry, respectively, and serum levels of IGF-I and leptin were measured with radioimmunoassay. Dramatic changes in weight, tibial length and EGP height were observed following 10 days of 40% FR. The protein levels of IGF-I receptor (IGF-IR) and GH receptor (GHR), which were reduced during FR, increased during catch-up growth without an apparent change in the level of their RNA. The levels of type II and X collagens were unchanged. Serum IGF-I and leptin levels were reduced during FR and increased during catch-up growth. Following 40% FR, there was a significant decrease in the level of GHR and IGF-IR in the EGP which may explain the reduced effect of GH treatment in malnourished animals and children.     

Craniofacial and acral growth responses in growth hormone-deficient children treated with growth hormone

OBJECTIVES: To investigate the effects of growth hormone (GH) therapy on craniofacial growth and body proportions in growth hormone deficient children. STUDY DESIGN: By using a cross-sectional study design, we investigated GH effects on craniofacial growth with photographic facial morphometrics, head circumference, and hand and foot size in 52 children with GH deficiency (GHD) treated with GH (0.27 mg/kg/wk) for 0.19 to 15.5 years, compared with untreated children with GHD and normal first-degree relatives. To detect disproportion and to correct for stature, age and height age (HA) SD scores were analyzed. RESULTS: Untreated subjects with GHD had retarded facial height and width (P values=.001) compared with normal controls; small head circumference for age and HA (P=.001); small hands for age (P<.001) that were large for HA (P=.003); and small feet for age (P<.001) that were normal for HA. When compared with normal controls, GH-treated subjects had proportional facial heights but narrower facial widths. Head circumference, however, increased disproportionately to height (P=.001), becoming large for stature, and increasing with duration of therapy and cumulative GH dose (P<.001). Hands and feet grew proportionately to height. CONCLUSION: Growth hormone treatment with conventional doses partially corrects craniofacial deficits and does not adversely affect hand and foot growth but appears to result in excessive head circumference growth.     

Acceleration of growth rate in growth hormone-deficient children treated with human growth hormone-releasing hormone

Twenty-four growth hormone-deficient children were treated with growth hormone releasing hormone-40 (GHRH) for 6 months or longer. GHRH (1 to 4 micrograms/kg of body weight per dose) was administered subcutaneously every 3 h (n = 10); or every 3 h overnight only (n = 10); or by twice daily injections (n = 4). Twenty-one children had an increase in growth rate during GHRH treatment. The growth velocities (mean +/- SD; cm/yr) before and during treatment were, respectively: every 3 h 3.5 +/- 1.4 versus 10.0 +/- 2.2, p = 0.0001; overnight only 3.4 +/- 1.0 versus 6.2 +/- 2.1, p = 0.008; twice daily injections 3.2 +/- 1.8 versus 7.9 +/- 2.4, p = 0.06. Using these three modes of GHRH administration, different total daily amounts of GHRH were administered. Regression analysis of average daily dose versus growth velocity revealed a correlation coefficient (r) value of 0.57, p = 0.004. Sixteen children received extended treatment for periods varying from 9 to 30 months. Of these, seven children were treated continuously for 9 months with pump overnight only and 5 for 12 months with pump every 3 h. Their growth velocities were sustained at a similar rate as those observed at 6 months. Six children received both twice daily and three hourly treatments consecutively. The growth velocities were similar during both treatments. Eleven children developed circulating antibodies to GHRH during treatment, however, all 11 had accelerated growth rates during GHRH therapy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Seasonal variation in growth during growth hormone therapy

Seasonal variation in growth of normal children has been well described, although the mechanism by which it occurs has not been elucidated. The growth of 52 growth hormone-deficient children treated with synthetic human growth hormone was analyzed. A similar seasonal variation was observed, with mean (+/- SEM) peak growth occurring in the summer (8.2 +/- 0.3 cm/y) and winter (7.7 +/- 0.2 cm/y), and trough growth occurring in the autumn (6.9 +/- 0.3 cm/y). Forty-seven percent of subjects grew minimally during the autumn, and only two children showed peak growth in that season. Individual variations between maximal and minimal growth seasons amounted to 3.5 +/- 0.3 cm/y. The seasonal pattern was statistically significant for the group as a whole, for the prepubertal subgroup, and for the boys. The variation persisted when the first year of treatment was excluded to avoid bias of the initial growth spurt. The season of onset of therapy did not affect total growth during the first year. The demonstration of a seasonal pattern in growth of these children suggests that the seasonal variation may be mediated by peripheral rather than central factors. Paired clonidine-provoked growth hormone levels and an integrated concentration of 24-hour growth hormone levels and serum levels of insulinlike growth hormone I measured in a control group of normally growing children were also analyzed and showed no seasonal variation. This further suggests that peripheral rather than central factors are responsible for the seasonal variation in children's growth.     

Insulin like growth factors axis and growth disorders

The growth hormone-insulin like growth factor (GH-IGF) axis plays a crucial role in the regulation of growth. Initially considered to be a mediator of growth hormone actions, IGF axis has been established as an independent endocrine system with wide array of actions. Recent advances have led to tremendous increase in the clinical utility of the IGF axis. IGF-based investigations (IGF1 and IGF binding protein 3) are now replacing GH-based investigations for evaluation and monitoring of disorders of the GH-IGF axis. IGF therapy has been successfully utilized in growth hormone insensitivity syndrome and GHD type 1B. The possibility of IGF axis as therapeutic options is being explored in wide variety of disorders like hypoxic-ischemic encephalopathy, Alzheimer's disease and psoriasis.