[Molecular analysis of the gene of steroidogenic acute regulatory protein (StAR) in adrenal incidentaloma].

The steroidogenic acute regulatory protein (StAR) plays an essential role in steroidogenesis, facilitating cholesterol entry into the inner compartment of mitochondria. Mutations (either transitions or transversions) of StAR gene have been described as a cause of lethal forms of congenital lipoid adrenal hyperplasia. Adrenal incidentalomas are frequently discovered during radiologic examinations performed in patients with diagnosis for other diagnostic problems. Enzymatic defects along the steroidogenetic cascade are observed with high frequency in these patients. Aim of the present study was to asses the involvement of alteration of the StAR gene in incidentally discovered adrenal masses (incidentalomas). The mutational analysis of 32 incidentalomas demonstrated a "missense" mutation in exon five of the gene in one of the tumors analysed. This is the first evidence of an alteration of the StAR gene in adrenal incidentalomas

Two polyclonal antisera detect different AGE epitopes in human plasma samples

Advanced glycation end products (AGEs), involved in the pathogenesis of diabetic complications, comprise a series of related chemical structures which might possess dissimilar immunogenic characteristics. In this study the levels of AGE in plasma samples from normal subjects (N/41) and diabetic patients (N/44) were measured by ELISA using two polyclonal antisera (named CF5 and CF199, respectively, and immunologically characterized) raised using two different immunogens and immunization techniques. Age levels were significantly higher in diabetic than in normal plasma samples (PB/0.0001) with both antisera. However, CF199 detected higher AGE levels than CF5 both in normal (PB/0.0001) and diabetic (PB/0.005) samples. Pre-incubation with AGE/ bovine serum albumin (BSA) caused the loss of most the reactivity of both antisera. Pre-incubation with carboxy-methyl-lysine/ BSA (an oxidation-derived AGE) induced the loss of nearly all CF5 reactivity while CF199 retained a significant amount of activity against AGE antigens. Moreover, CF5 lost over 90% of its reactivity against BSA incubated with high glucose under non-oxidative conditions, suggesting its recognition of mainly oxidation-derived AGE epitopes. The different AGE levels measured by the two antisera suggests, therefore, that one single antiserum is unable to recognize all the various AGE epitopes which might be present, at any time, in tissues and body fluids in health and disease