Mitotic spindle positioning protein (MISP) deficiency exacerbates dextran sulfate sodium (DSS)-induced colitis in mice

Inflammatory bowel disease (IBD) is classified into two types: Crohn's disease and ulcerative colitis. In IBD, the imbalance between the pro-inflammatory and anti-inflammatory cytokines prevents recovery from the inflammatory state, resulting in chronic inflammation in the colon. The mitotic spindle positioning protein (MISP) is localized to the apical membrane in the colon. In this study, we observed increased expression of MISP in the intestinal epithelial cells in dextran sulfate sodium (DSS)-induced colitis in mice. MISP-deficient mice receiving DSS showed significant exacerbation of colitis (e.g., weight loss, loss of the crypts). The intestinal epithelial cells of the MISP-deficient mice showed a trend towards decreased cell proliferation after DSS treatment. Reverse transcription followed by quantitative polymerase chain reaction revealed that the expression levels of Tgfb1, an anti-inflammatory cytokine, were significantly reduced in the colon of MISP-deficient mice compared with the wild-type mice regardless of DSS treatment. These findings indicate that MISP may play a role in the recovery of the colon after inflammation through its anti-inflammatory and proliferative activities, suggesting that MISP may be a new therapeutic target for IBD.

Positive correlation between renal tubular flattening and renal tubular injury/interstitial fibrosis in murine kidney disease models

The number of patients with chronic kidney disease (CKD) is growing continuously globally. In order to study pathogenesis and mechanisms, many animal models have been developed, including spontaneous, genetic, and induced models. Although each type of CKD shows disease-specific tissue changes in the early stages, tubular disorder and interstitial fibrosis histologically occur in the course of progression to end-stage renal failure. Therefore, the quantification of tubular disorder and interstitial fibrosis in CKD research using animal models is essential for measuring the degree of CKD severity and, thus, efficacy of therapeutic agents. Several strategies have been used to quantify interstitial fibrosis. Among scoring factors, renal tubular flattening can be quantitatively evaluated easily and inexpensively. However, the diagnostic value of renal tubular flattening evaluation has not been investigated previously. Therefore, in this study, we investigated the correlation between renal tubular flattening and interstitial fibrosis or renal tubular injury markers. We observed a strong correlation between the degree of tubular injury/interstitial fibrosis and renal tubular flattening in three types of mouse renal disease model. This is advantageous because rapidly advancing technologies such as artificial intelligence and image processing can be easily applied; hence, a more precise, objective, and quantitative diagnosis should be possible in the future.