Cholesterol induces fetal rat enterocyte death in culture

Abstract

The effect of cholesterol on fetal rat enterocytes and IEC-6 cells (line originated from normal rat small intestine) was examined. Both cells were cultured in the presence of 20 to 80 µM cholesterol for up to 72 h. Apoptosis was determined by flow cytometric analysis and fluorescence microscopy. The expression of HMG-CoA reductase and peroxisome proliferator-activated receptor gamma (PPARγ) was measured by RT-PCR. The addition of 20 µM cholesterol reduced enterocyte proliferation as early as 6 h of culture. Reduction of enterocyte proliferation by 28 and 41% was observed after 24 h of culture in the presence and absence of 10% fetal calf serum, respectively, with the effect lasting up to 72 h. Treatment of IEC-6 cells with cholesterol for 24 h raised the proportion of cells with fragmented DNA by 9.7% at 40 µM and by 20.8% at 80 µM. When the culture period was extended to 48 h, the effect of cholesterol was still more pronounced, with the percent of cells with fragmented DNA reaching 53.5% for 40 µM and 84.3% for 80 µM. Chromatin condensation of IEC-6 cells was observed after treatment with cholesterol even at 20 µM. Cholesterol did not affect HMG-CoA reductase expression. A dose-dependent increase in PPARγ expression in fetal rat enterocytes was observed. The expression of PPAR-γ was raised by 7-and 40-fold, in the presence and absence of fetal calf serum, respectively, with cholesterol at 80 mM. The apoptotic effect of cholesterol on enterocytes was possibly due to an increase in PPARγ expression.

Diagnostic utility of selected faecal biochemical parameters in the determination of acute diarrhoea and associated defecation stooling characteristics in dogs: An observational study

“…This is believed to occur due to the upregulation of peroxisome proliferator-activated receptor-gamma (PPARg), which reduces intestinal cell growth by triggering apoptosis. This phenomenon has been observed in a laboratory experiment involving rat enterocytes ( Gazzola et al, 2004 ; Ringseis et al, 2007 ). Analysis of the average intestine total cholesterol levels in study participants with and without diarrhoea ( Table 2b ) indicates that intestinal total cholesterol is strictly regulated to the extent that even a modest increase in its level can lead to diarrhoea.…”

“…The intestinal presence of biochemical parameters such as urea, creatinine, total bilirubin, total cholesterol, uric acid, triglycerides, and gamma-glutamyl transferase (GGT) has been reported in dogs ( Forster et al, 2018 ; Kilburn et al, 2020 ). These parameters are commonly measured in serum to evaluate the health condition of humans ( Gazzola et al, 2004 ; Weiner et al, 2015 ) and the general well-being of domestic animals ( Kozat & Sepehrizadeh, 2017 ). Enterocytes and gut bacteria have been found to collectively generate certain quantities of urea through their metabolic processes ( Patra & Aschenbach, 2018 ).…”

“…Enteric bacteria convert unabsorbed cholesterol from digested food into coprostanone and coprostanol ( Lye et al, 2010 ). Without this, cholesterol can trigger apoptosis in intestinal cells ( Gazzola et al, 2004 ). Enterocytes further release gamma-glutamyl transferase, while the gut microbiota generates uric acid through the breakdown of purines ( Shao et al, 2017 ).…”