Spatial Proteomics Reveals Alcohol-Induced Damages to the Crypts and Villi of the Mouse Small Intestine

Alcohol consumption perturbs the gut immune barrier and
ultimately
results in alcoholic liver diseases, but little is known about how
immune-related cells in the gut are perturbed in this process. In
this study, we employed laser capture microdissection and a label-free
proteomics approach to investigate the consequences of alcohol exposure
to the proteomes of crypts and villi in the proximal small intestine.
Intestinal tissues from alcohol-fed and pair-fed mice were microdissected
to selectively capture cells in the crypts and villi regions, followed
by one-pot protein digestion and data-independent LC–MS/MS
analysis. We successfully identified over 3000 proteins from each
of the crypt or villi regions equivalent to ∼3000 cells. Analysis
of alcohol-treated tissues indicated an enhanced alcohol metabolism
and reduced levels of α-defensins in crypts, alongside increased
lipid metabolism and apoptosis in villi. Immunofluorescence imaging
further corroborated the proteomic findings. Our work provides a detailed
profiling of the proteomic changes in the compartments of the mouse
small intestine and aids in molecular-level understanding of alcohol-induced
tissue damage.