Altered plasma levels of nerve growth factor and transforming growth factor-beta2 in type-1 diabetes mellitus.
Nerve growth factor (NGF) and transforming growth factor-beta2 (TGF-beta2) are cytokines which have known immunological effects. An elevated level of NGF has been reported in certain autoimmune diseases, whereas TGF-beta2 is an immunosuppressor which is known to play a role in regulating cell proliferation. A role of this cytokine has been proposed in the pathogenesis of type-1 diabetes mellitus (IDDM), but no clinical studies have yet measured its serum level in this disease. In this study we measured the levels of NGF and TGF-beta2 in the sera of patients with IDDM (n = 26) and values were compared to those of age-matched normal subjects (n = 27) and also to patients with type-2 diabetes mellitus (NIDDM) (n = 26) with similar HbA1c levels and an equal duration of diabetes. Serum NGF levels were significantly elevated in IDDM patients compared to those of age-matched controls (p <.001) and NIDDM controls (p <.01). TGF-beta2 levels were lower in IDDM patients when compared with the healthy control (p <.001) and the NIDDM control (p <.05). There was no correlation between the levels of NGF and TGF-beta2. The duration of diabetes and the level of HbA1c did not affect the NGF and TGF-beta2 levels in the IDDM patients. We conclude that an increase in NGF and a suppression in TGF-beta2 levels are present in patients with type-1 diabetes mellitus and that both cytokines may play independent roles in the pathogenesis of this disease.
Azar
S T
ST
Division of Endocrinology, American University of Beirut, Beirut, Lebanon.
Major
S C
SC
Safieh-Garabedian
B
B
D000293:Adolescent; D000328:Adult; D000368:Aged; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020932:Nerve Growth Factor / Q000097:blood*; D012016:Reference Values; D016212:Transforming Growth Factor beta / Q000097:blood*
D016212:Transforming Growth Factor beta; D020932:Nerve Growth Factor