Antimicrobial activity of neuropeptides against a range of micro-organisms from skin, oral, respiratory and gastrointestinal tract sites

Many neuropeptides are similar in size, amino acid composition and charge to antimicrobial peptides. This study aimed to determine whether the neuropeptides substance P (SP), neurokinin A (NKA), calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP), displayed antimicrobial activity against Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. SP, NPY, VIP and CGRP displayed variable degrees of antimicrobial activity against all the pathogens tested with the exception of S. aureus. These antimicrobial activities add a further dimension to the immunomodulatory roles for neuropeptides in the inflammatory and immune responses. (c) 2008 Elsevier B.V. All rights reserved.

Oral Resveratrol Reduces Neuronal Damage in a Model of Multiple Sclerosis

Background: Neuronal loss in multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE), correlates with permanent neurological dysfunction. Current MS therapies have limited the ability to prevent neuronal damage. Methods: We examined whether oral therapy with SRT501, a pharmaceutical grade formulation of resveratrol, reduces neuronal loss during relapsing-remitting EAE. Resveratrol activates SIRT1, an NAD-dependent deacetylase that promotes mitochondrial function. Results: Oral SRT501 prevented neuronal loss during optic neuritis, an inflammatory optic nerve lesion in MS and EAE. SRT501 also suppressed neurological dysfunction during EAE remission, and spinal cords from SRT501-treated mice had significantly higher axonal density than vehicle-treated mice. Similar neuroprotection was mediated by SRT1720, another SIRT1-activating compound; and sirtinol, an SIRT1 inhibitor, attenuated SRT501 neuroprotective effects. SIRT1 activators did not prevent inflammation. Conclusions: These studies demonstrate that SRT501 attenuates neuronal damage and neurological dysfunction in EAE by a mechanism involving SIRT1 activation. SIRT1 activators are a potential oral therapy in MS. © 2010 by North American Neuro-Ophthalmology Society.