Effects of Fasting at Different Stages of Lighting Regimen on the Proliferation of Jejunal Epithelial Cells During Rat Pup Weaning

Abstract

The lifespan of intestinal epithelial cells is predetermined by the process of cell proliferation that occurs constantly in the crypt. The control of this process involves some endogenous factors, such as hormones, as well as exogenous factors, like food and natural light variations. These last two exogenous factors seem to be the major modulators of the cell proliferation process. Fasting treatment was conducted to assess the role of food and its effect on the metaphase index (MI) of the intestinal epithelium at different times and periods (light and dark) of the day. The effects of short-(5 hr) and long-term (25 hr) fasting on the MI in the jejunal epithelium of young rats were investigated at 09:00 h, 15:00 hr, 21:00 hr, and 02:00 hr using the arrested metaphases method. The present study demonstrates that 5 hr and 25 hr of fasting treatment decrease the MI at 09:00 hr. It was observed from MI analysis that there is an interaction between the fed/fasted status of the animal and the different times of the day. This result suggests that during the transition from youth to adulthood, the control of MI by the light/dark cycle seems to be more pronounced as compared with control by food intake at some periods of the day, although at other times food had a greater impact on the MI. Anat Rec, 292:955-959, 2009. V V C 2009 Wiley-Liss, Inc.

Histological aspects of the small intestine under variable feed restriction: The effects of short and intense restriction on a growing rabbit model

“…In a previous study, which evaluated the morphometric changes in the small intestine of nursing piglets caused by 60% restriction, it was stated that this restriction resulted in a significantly reduced thickness of the mucosa and villus height compared with the control group ( 21 ). In other studies it was revealed that starvation induces proximal small intestine intestinal epithelial atrophy ( 22 , 23 ), which is more closely associated with increased epithelial cell apoptosis ( 24 ) than with the full process of cell proliferation in the crypts ( 25 ) and is the main cause of increased mucosal permeability ( 26 ). In the present study, which was oriented on the histological aspects of feed restriction, no pathological changes were observed.…”

Expression of the matrix metalloproteinases 2 and 9 in the rat small intestine during intrauterine and postnatal life

“…Additionally, it also acts as a barrier between the internal and external environments (De Mey & Freund, 2013). However, during all developmental stages, the organ is influenced by external factors, mainly light and food (Soares, Okada, Ayub, & Gomes, 2009). In mammals, the first food intake after birth is milk.…”

Are the Matrix Metalloproteinases 2 and 9 beeing expressed in the mucosa of the rat small intestine during its intrauterine and postnatal life development ?

“…In addition, small intestine also acts as a barrier between the body internal and external environment (De Mey and Freund, 2013). However, during all phases of development, the small intestine is under influence of the external factors, mainly light and the food (Soares et al, 2009). In mammalian, the first food intake after birth is milk.…”