指定課題研究報告
SERUM TUMOR NECROSIS FACTOR-ALPHA IN PATIETS WITH ADULT GROWTH HORMONE DEFICIENCY

Naomi Hizuka, Emina Itoh, Izumi Fukuda, Yukiko Ishikawa, Kumiko Yasumoto, Yuko Murakami, Akira Sata, Kazue Takano Department of Medicine II, Tokyo Women's Medical University, Tokyo, 162-8666, Japan

AIM

　Patients with adult growth hormone deficiency (AGHD) have altered body composition, abnormal lipid profile, increased prevalence of athelosclerosis, and reduced quality of life. Recently, the beneficial effects of GH replacement therapy to these patients have been reported. We previously reported that hyperlipidemia and impaired glucose tolerance were found in 57% and 20% of AGHD, and that increased intima-media thickness of carotid arteries were found in 38% of AGHD. One of the possible mechanism of these abnormalities is an increase of insulin resistance that might be related to increased body fat with abdominal preponderance. Increased tumor necrosis factor-α ( TNF-α) secreted from fat cells might cause insulin resistance in these patients. In the present study, we measured serum TNF-α levels in patients with AGHD and investigated the relationship between the TNF-α levels and the values of homeostasis model assessment of insulin resistance (HOMA-R).

SUBJECTS AND METHODS

　Thirty-two patients with AGHD (M/F: 15/17) with a mean age of 46±18 (18~77) yrs and thirty control subjects (M/F: 15/15) with a mean age of 46±13 (25~72) yrs were studied. 　
　Serum TNF-α levels were measured by ELISA. Body mass index (BMI) and HOMA-R were also investigated in these subjects.

RESULTS

　Serum TNF-α levels in patients with AGHD ranged from 0.8 to 10.3, with a mean of 2.34±0.33 pg/ml. The values were higher than those in controls (1.72±0.18 pg/ml; P<0.05). BMI and HOMA-R values in AGHD were significantly greater than those in controls (23.2±0.7 vs 20.8±0.3, P<0.01; 2.54±0.37 vs 1.44±0.06, P<0.01). Serum TNF-α levels did not correlate with HOMA-R and BMI in AGHD.

CONCLUSIONS

　These data demonstrate that serum TNF-α levels and insulin resistance are increased in AGHD. The TNF-α levels did not correlated with the index of insulin resistance, however, the increased TNF-α values might play some role in prevalence of athelosclerosis in AGHD.