Cellular localization and regulation of receptors and enzymes of the endocannabinoid system in intestinal and systemic inflammation

AbstractSurveys suggest thatCannabis provides benefit for people with inflammatory bowel disease. However, mechanisms underlying beneficial effects are not clear. We performed in situ hybridization RNAscope® combined with immunohistochemistry to show cell-specific distribution and regulation ofcannabinoid receptor 1 and2 (CB1,CB2),G protein-coupled receptor 55 (GPR55), andmonoacylglycerol lipase (MGL) mRNA in immune cells using murine models of intestinal and systemic inflammation. In healthy animals, the presence in enteric ganglia is high forCB1 mRNA, but low forCB2 andGPR55 mRNAs.MGL mRNA is predominant throughout the intestinal wall including myenteric neurons, epithelium, circular and longitudinal muscular layers, and the lamina propria. Within the immune system, B220+ cells exhibit high gene expression forCB2 while the expression ofCB2 in F4/80+ and CD3+ cells is less prominent. In contrast,GPR55 mRNA is highly present in F4/80+ and CD3+ cells. qRT-PCR of total colonic segments shows that the expression ofGPR55 andMGL genes drops during intestinal inflammation. Also at cellular levels,GPR55 andMGL gene expression is reduced in F4/80+, but not CD3+ cells. As to systemic inflammation, reduced gene expression ofMGL is observed in ileum by qRT-PCR, while at cellular levels, altered gene expression is also seen forCB1 andGPR55 in CD3+ but not F4/80+ cells. In summary, our study reveals changes in gene expression of members of the endocannabinoid system in situ attesting par...
Source: Histochemistry and Cell Biology - Category: Biomedical Science Source Type: research