Biology subjects

Devi, K.

Publications and source records attributed to Devi, K..

2 recordsLinked to original sources

bioRxiv2021

Colon Innervating TRPA1 Positive Nociceptors Influence Mucosal Health In Mice

IntroductionTransient receptor potential ankyrin-1 positive (TRPA1+ve) nociceptors, primarily present as peptidergic neuronal afferents in the colon are sensors of disturbance in lower gastrointestinal tract including pain induced by different pathologies. Their therapeutic role in the alleviation of chronic pain (receptor antagonism and receptor desensitization) associated with inflammatory bowel diseases (IBD) is reported. However, there is limited literature available about their role in formation and sustenance of the mucosal layer, and its interaction with host physiology as well as luminal microbial community. The aim of this study focuses on the effects of nociceptive TRPA1 channel desensitization on colonic mucus production and gut health. MethodsTRPA1+ve nociceptors were desensitized by rectal administration of capsazepine. Ileum, colon was harvested and cecum content was collected. We performed morphological/histological analysis, gut permeability alteration, gene expression changes, colon metabolite profiling, and gut microbial abundance in these animals. ResultsWe found that presence of TRPA1-positive nociceptors is required for mucus layer integrity, using an intra-rectal capsazepine-induced TRPA1 desensitization model. Desensitization of TRPA1 positive nociceptors resulted in damaged mucosal lining, resultant increase in gut permeability and altered transcriptional profile of genes for goblet cell markers, mucus regulation, immune response and tight junction proteins. The damage to mucosal lining prevented its role in enterosyne (short chain fatty acids) actions. ConclusionThese results suggest that caution may need to be exercised before employing TRPA1 desensitization as a therapeutic option to alleviate pain caused due to IBD.

pharmacology and toxicology↗

bioRxiv2021

Mucin-mimetic action of capsaicin improves high fat diet-induced gut barrier dysfunction in mice colon

The gut barrier - including tight junction proteins and mucus layers, is the first line of defense against physical, chemical, or pathogenic incursions. This barrier is compromised in various health disorders. Capsaicin, a dietary agonist of Transient receptor potential vanilloid 1 (TRPV1) channel, is reported to alleviate the complications of obesity. While its mode of action is well established to enhance energy expenditure, metabolism and prevent dysbiosis, the more local effects on the host gut - particularly the gut barrier and mucus system remain elusive. We employed a diet-induced obesity model to investigate the effect of capsaicin on the gut barrier and mucus production and to understand the involvement of mucus, bacteria, and TRPV1 in these phenomena. Mucin feeding reflected most of the effects produced by capsaicin, indicating that mucus modulation by capsaicin plays a crucial role in its anti-obesity effects. Capsaicin, bacteria and the host mucus system seem to act in a cyclic cascade involving TRPV1, which can be activated by capsaicin and various bacteria. These findings provide new insight into the role of TRPV1 in maintaining a healthy gut environment. HIGHLIGHTSO_LIExogenous mucin feeding produced anti-obesity effects similar to capsaicin in mice. C_LIO_LIMucin and capsaicin improved TJP expression, intestinal permeability and gut microbial diversity. C_LIO_LICapsaicin modulated bacterial diversity in vitro, independently of the host. C_LIO_LIProbiotic bacteria and butyrate activated TRPV1 in transfected HEK cells. C_LIO_LIAnti-obesity action of capsaicin is not exclusive to TRPV1 agonism. C_LIO_LICapsaicins action as colonic mucus secretagogue - plays a crucial part in its anti-obesity benefits. C_LI

pharmacology and toxicology↗