Appropriate leucine-richα-2 glycoprotein cut-off value for Japanese patients with ulcerative colitis

BACKGROUND It has been suggested that serum leucine-richα-2 glycoprotein(LRG)could be a novel monitoring biomarker for the assessment of disease activity in inflammatory bowel disease.In particular,the relationship between LRG levels and the endoscopically assessed activity of ulcerative colitis(UC)has become a matter of interest.AIM To clarify appropriate LRG cut-off values for the prediction of endoscopic and histologic remission in Japanese patients with UC.METHODS This was a cross-sectional,single-center,observational study of Japanese patients with UC.Among 213 patients with UC,in whom LRG was measured from September 2020 to February 2022,we recruited 30 patients for whom a total colonoscopy and measurements of LRG and C-reactive protein(CRP)were performed on the same day.We retrospectively analyzed correlations between the LRG and CRP levels and endoscopic indices,including the Mayo endoscopic subscore and UC endoscopic index of severity.RESULTS Correlations between the LRG values and the Mayo endoscopic subscore or UC endoscopic index of severity were significant(r=0.754,P<0.0001;r=0.778,P<0.0001,respectively).There were also significant correlations between CRP levels and Mayo endoscopic subscore or UC endoscopic index of severity(r=0.599,P=0.0005;r=0.563,P=0.0012,respectively),although the correlation coefficients were higher for LRG.The LRG cutoff value for predicting endoscopic remission was 13.4μg/mL for a Mayo endoscopic subscore of 0[area under the curve(AUC):0.871;95%confidence interval(CI):0.744-0.998],and 13.4μg/mL for an UC endoscopic index of severity of 0 or 1(AUC:0.904;95%CI:0.792-1.000).CONCLUSION LRG may be a surrogate marker for endoscopic activity in UC,with a cut-off value of around 13.4μg/mL for endoscopically inactive disease.

Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation

Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory proteins and/or their receptors are under investigation in ongoing clinical trials. Investigation has also been demonstrating that combinatorial therapies of growth inhibitors with other therapies, such as growth factors or stem-cell therapies, produce stronger results and their potential application in the clinics opens new venues in spinal cord injury treatment.