Altered plasma levels of nerve growth factor and transforming growth factor-β2 in type-1 diabetes mellitus

Sami T. Azar, Stella Major, Bared Safieh-Garabedian

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Nerve growth factor (NGF) and transforming growth factor-β2 (TGF-β2) are cytokines which have known immunological effects. An elevated level of NGF has been reported in certain autoimmune diseases, whereas TGF-β2 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-β2 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 HbAlc 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-β2 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-β2. The duration of diabetes and the level of HbAlc did not affect the NGF and TGF-β2 levels in the IDDM patients. We conclude that an increase in NGF and a suppression in TGF-β2 levels are present in patients with type-1 diabetes mellitus and that both cytokines may play independent roles in the pathogenesis of this disease.

Original languageEnglish
Pages (from-to)361-366
Number of pages6
JournalBrain, Behavior, and Immunity
Issue number4
Publication statusPublished - Dec 1999
Externally publishedYes



  • Autoimmunity
  • NGF
  • TGF-β2
  • Type-1 diabetes

ASJC Scopus subject areas

  • Immunology
  • Endocrine and Autonomic Systems
  • Behavioral Neuroscience

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