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Olga Scudiero,1,2 Ersilia Nigro,1 Marco Cantisani,3 Irene Colavita,1 Marilisa Leone,4 Flavia Anna Mercurio,4 Massimiliano Galdiero,5 Antonello Pessi,1 Aurora Daniele,1,6 Francesco Salvatore,1,2,7 Stefania Galdiero3,4 1CEINGE-Biotecnologie Avanzate Scarl, Naples, Italy; 2Dipartimento di Medicina Molecolare e Biotecnologie Mediche, 3Dipartimento di Farmacia, Università di Napoli Federico II, Naples, Italy; 4Istituto di Biostrutture e Bioimmagini, CNR, Naples, Italy; 5Dipartimento di Medicina Sperimentale, Seconda Università di Napoli, Naples, Italy; 6Dipartimento di Scienze e Tecnologie Ambientali Biologiche Farmaceutiche, Seconda Università di Napoli, Caserta, Italy; 7IRCCS Fondazione SDN, Naples, Italy Abstract: We have designed a cyclic 17-amino acid β-defensin analog featuring a single disulfide bond. This analog, designated “AMC” (ie, antimicrobial cyclic peptide), combines the internal hydrophobic domain of hBD1 and the C-terminal charged region of hBD3. The novel peptide was synthesized and characterized by nuclear magnetic resonance spectroscopy. The antimicrobial activities against gram-positive and gram-negative bacteria as well as against herpes simplex virus type 1 were analyzed. The cytotoxicity and serum stability were assessed. Nuclear magnetic resonance of AMC in aqueous solution suggests that the structure of the hBD1 region, although not identical, is preserved. Like the parent defensins, AMC is not cytotoxic for CaCo-2 cells. Interestingly, AMC retains the antibacterial activity of the parent hBD1 and hBD3 against Pseudomonas aeruginosa, Enterococcus faecalis, and Escherichia coli, and exerts dose-dependent activity against herpes simplex virus type 1. Moreover, while the antibacterial and antiviral activities of the oxidized and reduced forms of the parent defensins are similar, those of AMC are significantly different, and oxidized AMC is also considerably more stable in human serum. Taken together, our data also suggest that this novel peptide may be added to the arsenal of tools available to combat antibiotic-resistant infectious diseases, particularly because of its potential for encapsulation in a nanomedicine vector. Keywords: antimicrobial activity, cyclic mini-peptide, human beta-defensin

Background and purpose: Adiponectin is a cytokine linking energy metabolism and immune system. After being assembled, adiponectin circulates as oligomers of different molecular weight, i.e. low, medium and high (HMW) molecular weight. These have the most potent biological effects. Multiple sclerosis (MS) is an autoimmune disease of the human central nervous system. The aim of this study was to characterize the expression levels of both total adiponectin and its oligomerization state in the serum from 99 patients with MS at baseline (i.e. not influenced by therapies). We also investigated the potential relationships between adiponectin and disease progression and severity. Methods: Adiponectin was quantified and visualized by enzyme‐linked immunosorbent assay, western blotting and fast protein liquid chromatography. During the follow‐up (3.6 ± 2.20 years), the patients were evaluated using total annualized relapse rate and Expanded Disability Status Scale score. Results: Total adiponectin is statistically higher in patients with MS compared with matched controls (12.18 vs. 10.02 μg/mL, P = 0.001). Interestingly, the adiponectin oligomerization state is altered in MS, with an increase of HMW oligomers. In addition, patients with MS with higher levels of adiponectin at baseline have significantly higher risk of progression and severity (Multiple Sclerosis Severity Score, 3.84 vs. 2.44, P = 0.001). No statistical difference in adiponectin expression was found between active and inactive patients with MS and among the different forms of disease. Conclusions: This study demonstrated that adiponectin and its HMW oligomers are greatly involved in MS autoimmune disorder representing a potential biomarker to predict worse MS prognosis and severity. Further studies are required to clarify the molecular mechanisms underlying the properties of adiponectin and HMW oligomers in MS. [ABSTRACT FROM AUTHOR]