Serum levels of advanced glycation end products (AGEs) are increased and their soluble receptor (sRAGE) reduced in Hashimoto's thyroiditis.

PURPOSE: Advanced glycation end products (AGEs) are increased in conditions of oxidative stress and promote inflammation by interacting with their receptor RAGE on cell membrane. By contrast, the soluble receptor sRAGE exerts protective effects by competing with RAGE for ligand binding. AGEs/sRAGEs interaction is involved in the pathogenesis of several diseases related to oxidative stress. In the present study, we evaluated the AGEs/sRAGEs oxidative balance in Hashimoto' thyroiditis (HT). METHODS: We measured the levels of sRAGE, by ELISA, and AGEs, by spectrophotometric method, in the serum of 50 HT patients (5 M, 45 F; mean age 38.5 ± 12 years) and 50 age-, sex- and BMI-matched healthy controls. All subjects were euthyroid at recruitment and none was on LT-4 therapy. RESULTS: Serum sRAGEs were significantly lower (median 424 vs 738 pg/ml; p = 0.001) and AGEs higher (205 vs 114 AU/g prot; p = 0.001) in HT patients compared to controls, and the two parameters were inversely correlated (p = 0.016). Accordingly, the AGEs/sRAGEs ratio was threefold higher in HT patients than controls (0.48 vs 0.15; p = 0.0001). In regression analysis models, serum TPO-Ab were the main predictors for AGEs and sRAGEs levels and AGEs/sRAGEs ratio (p < 0.0001), irrespective of TSH and/or FT4 values. CONCLUSION: sRAGEs were decreased and AGEs increased, suggesting a dysregulation of AGE/sRAGEs-related oxidative homeostasis in HT patients, even when in euthyroid status. Autoimmunity per se seems to play an important role in AGEs/sRAGE imbalance, irrespective of thyroid function alterations.

Increased serum interleukin-22 levels in patients with PRL-secreting and non-functioning pituitary macroadenomas.

Cytokines' involvement in tumorigenesis has been hypothesized. Interleukin-22 (IL-22) is implicated in proliferative and anti-apoptotic pathways via its receptor IL-22R. Its role in pituitary adenomas has never been investigated. Twenty-seven patients with pituitary macroadenomas (PA, 21 males, mean age 53.8 ± 14.4 years) and 30 healthy controls (19 males, mean age 50.4 ± 8.4 years) were enrolled. Out of 27 PA patients, 17 had a non-functioning tumour (NFPA) and 10 a PRL-secreting adenoma (PRL-oma). Serum IL-22 levels were measured in both patients and controls. Immunohistochemical (IHC) tumoral IL-22R expression was evaluated in 10 patients with NFPA and 4 with PRL-oma. IL-22 levels were significantly higher in PA patients than in controls [32.47 (11.29-70.12) vs. 5.58 (0.19-21.46) pg/mL, p < 0.0001] but did not correlate with tumor maximum diameter and were not associated to pituitary function impairment. PRL-oma patients had significantly higher IL-22 levels than NFPA patients [37.18 (14.82-70.12) vs. 21.29 (11.29-56) pg/mL, p = 0.039]. IHC revealed a strong IL-22R staining in 100 % of PRL-omas and 60 % of NFPAs. We provide the first evidence of increased serum IL-22 levels in patients with pituitary macroadenoma, especially in PRL-omas, regardless of tumor size and/or degree of pituitary function impairment. We also demonstrated the expression of IL22R in all PRL-omas and in 60 % of NFPAs.

Is interleukin-22 a possible indicator of chronic heart failure's progression?

Chronic heart failure (CHF) is a complex and heterogeneous clinical syndrome and because of its rising incidence and prevalence, it can be considered a global epidemic. Interleukin (IL)-22 is a pro-inflammatory cytokine, belonging to the IL-10 family. Forty-seven consecutive older patients, hospitalized with an admitting diagnosis of CHF at the Geriatric Medicine Unit (University of Messina, Italy), from 01/01/06 to 30/06/06, were enrolled in the study. Serum concentrations of IL-22 were measured by a quantitative enzyme immunoassay technique. IL-22 levels in all CHF patients were significantly higher than those in controls, in particular, only the II and III NYHA class had IL-22 values significantly higher than the controls, whereas there was no difference between the IL-22 levels of NYHA class IV and the controls. The reason may be the declining immune function in CHF older patients, in fact we can hypothesize that the fall in IL-22 levels, with the progression of NYHA class, is due to the reduced ability in CHF patients to respond to infections, as IL-22 has anti-microbial properties. We detected different outcomes correlated to different IL-22 levels, and the Kaplan-Meier curves suggest a trend.