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- Charepalli, Venkata, et al.
(författare)
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Pigs, unlike mice, have two distinct colonic stem cell populations similar to humans that respond to high-calorie diet prior to insulin resistance
- 2017
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Ingår i: Cancer Prevention Research. - 1940-6207. ; 10:8, s. 442-450
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Tidskriftsartikel (refereegranskat)abstract
- Basal colonic crypt stem cells are long lived and play a role in colon homeostasis. Previous evidence has shown that high-calorie diet (HCD) enhances colonic stem cell numbers and expansion of the proliferative zone, an important biomarker for colon cancer. However, it is not clear how HCD drives dysregulation of colon stem cell/colonocyte proliferative kinetics. We used a human-relevant pig model and developed an immunofluorescence technique to detect and quantify colonic stem cells. Pigs (n = 8/group) were provided either standard diet (SD; 5% fat) or HCD (23% fat) for 13 weeks. HCD- and SD-consuming pigs had similar total calorie intake, serum iron, insulin, and glucose levels. However, HCD elevated both colonic proliferative zone (KI-67) and stem cell zone (ASCL-2 and BMI-1). Proliferative zone correlated with elevated innate colonic inflammatory markers TLR-4, NF-κB, IL6, and lipocalin-2 (r ≥ 0.62, P = 0.02). Elevated gut bacterial phyla proteobacteria and firmicutes in HCD-consuming pigs correlated with proliferative and stem cell zone. Colonic proteome data revealed the upregulation of proteins involved in cell migration and proliferation and correlated with proliferative and stem cell zone expansion. Our study suggests that pig colon, unlike mice, has two distinct stem cells (ASCL-2 and BMI-1) similar to humans, and HCD increases expansion of colonic proliferative and stem cell zone. Thus, pig model can aid in the development of preventive strategies against gut bacterial dysbiosis and inflammation-promoted diseases, such as colon cancer.
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| 2. |
- Sido, Abigail, et al.
(författare)
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A food-based approach that targets interleukin-6, a key regulator of chronic intestinal inflammation and colon carcinogenesis
- 2017
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Ingår i: Journal of Nutritional Biochemistry. - : Elsevier BV. - 0955-2863. ; 43, s. 11-17
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Tidskriftsartikel (refereegranskat)abstract
- Studies have shown a causal link between high-calorie diet (HCD) and colon cancer. However, molecular mechanisms are not fully elucidated. To understand etiology of HCD-induced colon carcinogenesis, we screened 10 pathways linked to elevated colonic cell proliferation and chronic inflammation in an HCD-consuming human-relevant pig model. We observed elevated colonic mucosal interleukin-6 (IL-6) expression in HCD-consuming pigs compared to standard diet controls (SD, P=.04), and IL-6 strongly correlated with Ki-67 proliferative index and zone, early biomarkers of colon cancer risk (r=0.604 and 0.743 and P=.017 and.002, respectively). Liquid chromatography–tandem mass spectrometry-based proteomic analysis and Ingenuity Pathway Analysis showed that HCD consumption altered IL-6 signaling pathway proteins (PI3KR4, IL-1α, Mapk10, Akt3, PIK3CG, PIK3R5, Map2k2). Furthermore, these proteins also correlated with Ki-67 proliferative index/zone. Anti-IL-6 therapeutics are available for treating colon cancer; however, they are expensive and induce negative side effects. Thus, whole foods could be a better way to combat low-grade chronic colonic inflammation and colon cancer. Whole plant foods have been shown to decrease chronic diseases due to the potential of anti-inflammatory dietary compounds acting synergistically. We observed that supplementation of HCD with anthocyanin-containing purple-fleshed potatoes (10% w/w), even after baking, suppressed HCD-induced IL-6 expression (P=.03) and the IL-6-related proteins IL-1α and Map2k1 (P≤.1). Our results highlight the importance of IL-6 signaling in diet-linked induction/prevention of colonic inflammation/cancer and demonstrate the potential of a food-based approach to target IL-6 signaling.
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