Growth Hormone and Insulin Resistance in Girls With Turner Syndrome or Idiopathic Short Stature
试验速览
- 阶段
- 不适用
- 状态
- 终止
- 入组人数
- 1
- 试验地点
- 1
- 主要终点
- to compare the effect of GH on IMCL content in the two subject groups (Turner syndrome vs. ISS)
研究概览
简要总结
Growth hormone treatment improves body fat distribution but also causes insulin resistance. Scientists have recently linked insulin resistance with special stores of fat in the muscles, which can be measured by magnetic resonance imaging (MRI). The researchers hypothesize that growth hormone will paradoxically reverse the linkage between muscle fat stores and insulin resistance. To assess this association and to investigate the cause(s), the researchers will measure muscle fat stores during growth hormone treatment. Other parameters linked to insulin resistance (glucose tolerance, blood markers, and body composition) will also be assessed. This study may lead to improved strategies for monitoring growth hormone therapy.
详细描述
Growth hormone (GH) treatment can cause insulin resistance (IR) despite its overall favorable influence on body fat composition. IR is associated with special stores of fat in the muscle (intramyocellular lipid or IMCL), which can be measured by MRI. The researchers hypothesize that changes in IR during GH treatment will be associated with a predictable, but possibly contradictory, change in muscle fat stores. Girls receiving GH for short stature, due to Turner syndrome or idiopathic short stature (ISS), will be studied both during and without GH treatment to assess the impact of GH treatment on muscle fat stores.
Hypothesis: Girls with Turner syndrome will have increased IMCL, corresponding to their insulin resistance, when compared to girls with ISS. GH treatment may paradoxically reverse this association in girls with Turner syndrome.
Objectives: The objectives are to assess changes in IMCL during GH therapy and to increase the researchers' knowledge of GH action.
Study Design: Prepubertal girls receiving GH therapy for short stature due to Turner syndrome or ISS will be recruited to participate in a crossover study. Subjects will be studied twice: first during GH treatment and at baseline, following washout without GH for 3 months. GH treatment for up to 6 months will be provided for eligible girls not currently receiving GH. Assessments include:
- IMCL (soleus and tibialis anterior) measured non-invasively by proton magnetic resonance spectroscopy (1H-MRS)
- Body composition measured by DEXA and morphometry
- Whole body insulin sensitivity assessed by oral glucose tolerance
- Levels of plasma lipids and hormones
研究设计
- 研究类型
- Observational
- 观察模型
- Case Control
- 时间视角
- Prospective
入排标准
- 年龄范围
- 7 Years 至 14 Years（Child）
- 性别
- Female
- 接受健康志愿者
- 否
入选标准
- •Girls, with Turner syndrome or ISS; height standard deviation score (SDS) ≤ -2
- •Bone age ≤ 12 years
- •Normal birthweight
- •Body mass index (BMI) = 10th-90th percentile
- •Normal childhood activity; no physical or other limitations
- •Normal, balanced diet (20-40% calories from fat)
排除标准
- •Puberty (beyond Tanner Stage 1)
- •Diabetes in subject or first degree relative
- •Sex steroid therapy
- •Chronic conditions requiring medication (treatment for hypothyroidism is permissible)
- •Significant systemic disease (pulmonary, cardiac, renal, or other)
- •Non-removable metal
研究组 & 干预措施
Turner syndrome
Girls, aged 7-14, with short stature due to Turner syndrome and eligible for growth hormone therapy
干预措施: somatropin (rDNA) (Drug)
Control / idiopathic short stature
Girls, aged 7-14, with idiopathic short stature and eligible for growth hormone therapy
干预措施: somatropin (rDNA) (Drug)
结局指标
主要结局
to compare the effect of GH on IMCL content in the two subject groups (Turner syndrome vs. ISS)
时间窗: 3 months
次要结局
- to assess the relationship of IMCL to IR-associated plasma markers in each groups(3 months)
- to assess the relationship of IMCL to the effect of GH therapy in each groups(3 months)