Alterations in Gastric Mucosal Expression of Calcitonin Gene-Related Peptides, Vanilloid Receptors, and Heme Oxygenase-1 Mediate Gastroprotective Action of Carbon Monoxide against Ethanol-Induced Gastric Mucosal Lesions

Abstract

Carbon monoxide (CO) has been reported to contribute to the maintenance of gastric mucosal integrity, gastroprotection, and ulcer healing. However, involvement of transient receptor potential vanilloid receptor type 1 (TRPV1) located on afferent sensory fibers endings and sensory neuropeptide calcitonin gene-related peptide (CGRP) in CO-mediated gastroprotection against ethanol-induced gastric damage has not been explored. Male Wistar rats with and without denervation of afferent sensory neurons induced by capsaicin (total dose 125 mg/kg within 3 days) were pretreated with vehicle, CO donor tricarbonyldichlororuthenium (II) dimer (CORM-2, 5 mg/kg i.g.), administered alone or with CGRP-α (10 μg/kg i.p.) or TRPV1 antagonist capsazepine (5 mg/kg i.g.), followed 30 min later by intragastric (i.g.) administration of 75% ethanol. The area of gastric damage and gastric blood flow (GBF) were assessed planimetrically and by laser flowmetry, respectively. Microscopic evaluation of ethanol-induced gastric lesions was performed after haematoxylin/eosin (H&E) or alcian blue/periodic acid-Schiff/alcian blue (AB/PAS) staining. Gastric mucosal mRNA fold change for heme oxygenase (HMOX)-1, HMOX-2, CGRP-α, CGRP-β, inducible nitric oxide synthase (iNOS), endothelial (e)NOS, neuronal (n)NOS, cyclooxygenase (COX)-1, COX-2, and protein expression for HMOX-1 and TRPV1 was determined by real-time PCR or Western blot, respectively. Pretreatment with CORM-2 combined or not with CGRP reduced ethanol-induced gastric lesions and elevated GBF. Capsaicin-denervation or co-treatment with capsazepine or CGRP and CORM-2 in capsaicin-denervated animals failed to affect these beneficial effects of CO donor. In rats with intact sensory nerves, CORM-2 increased gastric mRNA level for HMOX-1 and CGRP-α. In capsaicin-denervated rats, CORM-2 increased eNOS mRNA fold change and TRPV1 protein expression while capsaicin denervation itself decreased HMOX-1 protein expression and eNOS mRNA level. We conclude that CO prevents gastric mucosa from ethanol-induced lesions due to activation of TRPV1/CGRP-α system and accompanying increase in gastric microcirculation but independently on afferent sensory nerve activity despite the stimulation of TRPV1 protein and CGRP-α mRNA expression.

Evidence for Cytoprotective Effect of Carbon Monoxide Donor in the Development of Acute Esophagitis Leading to Acute Esophageal Epithelium Lesions

“…Expression for HMOX-1, HMOX-2, COX-1, COX-2, iNOS, nNOS, HIF-1α, annexin-A1, IL-1β, TNF-α, β-actin (ACTB) and succinate dehydrogenase complex (SDHA) was determined using specific primers [31][32][33]. Expression for IL-6R, IL-1R1, IL-1R2, IL-1RA, TNF-R2, NF-κB, c-Fos, c-Jun, SOCS3 was determined using specific primers described elsewhere [34].…”

“…Real-time PCR was conducted using thermal cycler Quant Studio 3 (Thermo Fisher Scientific, Waltham, MA, USA) and SYBR Green dye including kit (SG qPCR Master Mix (2x), EURx, Gdansk, Poland). Results were analyzed using ∆∆Ct method [32,35]. Results with at least two-fold up-or downregulation of mRNA expression vs. vehicle group and with p < 0.05 were considered and marked as statistically and biologically significant.…”

Protective Effects of Wheat Peptides against Ethanol-Induced Gastric Mucosal Lesions in Rats: Vasodilation and Anti-Inflammation

“…The destruction of gastric mucosal integrity is a result of an imbalance between defensive factors (mucus, bicarbonate, nitric oxide (NO), prostaglandins, and gastric mucosal blood flow) and the aggressive factors (hydrochloric acid and pepsin) [ 1 ]. Injurious agents such as Helicobacter pylori , non-steroid anti-inflammatory drugs (NSAIDs), alcohol abuse, and stress are the main factors responsible for gastric mucosal lesions creating fall in gastric mucosal blood flow and an impairment of mucosal defensive mechanisms [ 2 , 3 ].…”

Updated Role of Neuropeptide Y in Nicotine-Induced Endothelial Dysfunction and Atherosclerosis

“…Endothelial products, including nitric oxide synthases (NOS), hydrogen sulfide, prostacyclin, endothelins, and thromboxane A2 (TXA2), affect the contraction and dilation of human blood vessels ( 6 ). NOS, comprising endothelial NOS (eNOS), neuronal NOS (nNOS), and inducible NOS (iNOS) are critical enzymes in nitric oxide (NO) production ( 7 ). ECs prevent arteriosclerotic cardiovascular disease by maintaining the delicate balance between hemorrhage and thrombosis by inducing the expression of coagulation factors and anticoagulants such as tissue factor (TF), von Willebrand factor, and fibrinolytic components; enhancing endogenous antioxidant capacity, especially the secretion of eNOS; promoting angiogenesis by secreting angiogenic growth factors, such as vascular endothelial growth factor (VEGF) and fibroblast growth factor; organizing immune cell recruitment by secreting chemokines and adhesion molecules; and transporting nutrients and signals.…”