Aimaretti G, Baffoni C, Ambrosio M R, Maccario M, Corneli G, Bellone S, Gasperi M, Degli Uberti E, Ghigo E
Dipartimento di Medicina Interna, Università di Torino, Italy.
J Endocrinol Invest. 2000 Jan;23(1):5-11. doi: 10.1007/BF03343668.
Both IGF-I and DHEA-S undergo an age-related decrease and their decrease could be involved in age-related changes in body composition, structure functions and metabolism. On the other hand, it is well known that mean IGF-I levels are clearly reduced in hypopituitaric patients with GH deficiency (GHD) while data about dehydroepiandrosterone sulfate (DHEA-S) levels in hypopituitarism are scanty. We evaluated DHEA-S and IGF-I levels and their relationship in 90 patients with panhypopituitarism (HYPOPIT) with severe GHD [49 women and 41 men; age, mean+/-SE: 47.9+/-1.49 yr, range: 20-80 yr, BMI: 26.4+/-0.6 kg/m2; 21 with childhood-onset (CO) and 69 with adult-onset (AO) HYPOPIT]. DHEA-S and IGF-I levels were also evaluated in 24 HYPOPIT with GHD after 3-month recombinant human GH (rhGH) replacement. Data in HYPOPIT were compared with those in a large group of healthy controls (NS, 233 women and 103 men, aged 20-80 yr; all subjects were within +/-15% of their ideal body weight). In NS both DHEA-S levels and IGF-I were gender-independent while showed a strong, inverse correlation with age (r=-0.6; p<0.001 and r=-0.56; p<0.0001, respectively). Nevertheless, no relationship was found between DHEA-S and IGF-I levels in NS. In HYPOPIT, age-adjusted mean DHEA-S and IGF-I levels were clearly lower than those in NS (2.3+/-0.4 vs 16.0+/-0.7 microg/l, p<0.005; 71.1 +/- 4.5 vs 170+/-4.7 microg/l, p<0.005). IGF-I levels in CO-HYPOPIT were lower (p<0.01) than those in AO-HYPOPIT (49.6+/-4.8 vs 77.0+/-5.4 microg/l), while DHEA-S levels were similar in both subgroups (2.6+/-0.7 vs 2.3+/-0.4 microg/l). In HYPOPIT both DHEA-S and IGF-I were independent of age and gender while there was a trend toward a positive association between each other (r=0.45; p<0.003). Analyzing individual levels in HYPOPIT with respect to age-adjusted normal ranges, IGF-I levels were below normal in 84, 62 and 0% between 20-40, 40-60 and 60-80 yr, respectively. On the other hand, DHEA-S levels were below normal in 84, 86 and 67% between 20-40, 40-60 and 60-80, respectively. In HYPOPIT rhGH treatment strikingly increased IGF-I levels (150+/-3.2 vs 85.3+/-4.1 microg/l, p<0.005) while did not modify DHEA-S levels (1.7+/-0.2 vs 1.6+/-0.2 microg/l). In conclusion, our results demonstrate that DHEA-S and IGF-I are negatively and independently associated to age in physiological conditions but not in hypopituitaric patients in whom both are strikingly reduced. Both DHEA-S and IGF-I levels in HYPOPIT show some overlap with those in normal subjects; thus the assay of these parameters is not diagnostic for hypopituitarism. DHEA-S reduction in HYPOPIT does not depend on IGF-I as indicated also by evidence that GH replacement restores IGF-I but does not modify DHEA-S levels.
胰岛素样生长因子-I（IGF-I）和硫酸脱氢表雄酮（DHEA-S）水平均随年龄增长而下降，且它们的下降可能与身体成分、结构功能及代谢的年龄相关变化有关。另一方面，众所周知，生长激素缺乏（GHD）的垂体功能减退患者的平均IGF-I水平明显降低，而关于垂体功能减退患者硫酸脱氢表雄酮（DHEA-S）水平的数据却很少。我们评估了90例患有严重GHD的全垂体功能减退症（HYPOPIT）患者（49名女性和41名男性；年龄，均值±标准误：47.9±1.49岁，范围：20 - 80岁，体重指数：26.4±0.6 kg/m²；21例为儿童期发病（CO），69例为成年期发病（AO）的HYPOPIT）的DHEA-S和IGF-I水平及其关系。还评估了24例接受3个月重组人生长激素（rhGH）替代治疗的GHD垂体功能减退患者的DHEA-S和IGF-I水平。将垂体功能减退患者的数据与一大组健康对照者（NS，233名女性和103名男性，年龄20 - 80岁；所有受试者体重均在理想体重的±15%范围内）的数据进行比较。在NS组中，DHEA-S水平和IGF-I水平均与性别无关，但与年龄呈强烈的负相关（r = -0.6；p < 0.001和r = -0.56；p < 0.0001）。然而，在NS组中未发现DHEA-S与IGF-I水平之间存在关联。在垂体功能减退患者中，经年龄调整后的平均DHEA-S和IGF-I水平明显低于NS组（2.3±0.4 vs 16.0±0.7 μg/l，p < 0.005；71.1±4.5 vs 170±4.7 μg/l，p < 0.005）。儿童期发病的垂体功能减退症（CO-HYPOPIT）患者的IGF-I水平低于成年期发病的垂体功能减退症（AO-HYPOPIT）患者（49.6±4.8 vs 77.0±5.4 μg/l，p < 0.01），而两个亚组中的DHEA-S水平相似（2.6±0.7 vs 2.3±0.4 μg/l）。在垂体功能减退患者中，DHEA-S和IGF-I均与年龄和性别无关，但彼此之间有呈正相关的趋势（r = 0.45；p < 0.003）。根据年龄调整后的正常范围分析垂体功能减退患者的个体水平，20 - 40岁、40 - 60岁和60 - 80岁之间IGF-I水平低于正常的比例分别为84%、62%和0%。另一方面，20 - 40岁、40 - 60岁和60 - 80岁之间DHEA-S水平低于正常的比例分别为84%、86%和67%。在垂体功能减退患者中，rhGH治疗显著提高了IGF-I水平（150±3.2 vs 85.3±4.1 μg/l，p < 0.005），而未改变DHEA-S水平（1.7±0.2 vs 1.6±0.2 μg/l）。总之，我们的结果表明，在生理条件下，DHEA-S和IGF-I与年龄呈负相关且相互独立，但在垂体功能减退患者中并非如此，在这类患者中两者均显著降低。垂体功能减退患者的DHEA-S和IGF-I水平与正常受试者的水平有一定重叠；因此，这些参数的检测对垂体功能减退症并无诊断意义。垂体功能减退患者中DHEA-S的降低并不依赖于IGF-I，生长激素替代治疗可恢复IGF-I但不改变DHEA-S水平这一证据也表明了这一点。
