Effects of Diet Choice on Stem Cell Function Necessitate Clarity in Selection and Reporting

Abstract

Augenlicht and colleagues raise concerns about the impact of diet on stem cell regulation and call for more careful reporting on dietary conditions used in mouse studies on this topic. We agree that specific conditions for animal housing and care should be reported, and we encourage this in our STAR Methods guidelines for all papers. However, moving forward we will require more detailed reporting on dietary information for mouse studies where the main scientific focus concerns stem cell functions, and especially metabolism. This will include vendor information, stock number, and feeding schedules within the STAR Methods section and Experimental Models section of the Key Resource Table. We hope this will provide further reproducibility, robustness, and clarity in the papers we publish.Investigators treat ''chow diet'' as a singular entity and many stem cell papers do not provide any, or they provide insufficient, information to discern components of different ''chows.'' However, chow diets are prepared from products such as corn and wheat husks, oats, alfalfa, and soybean and fish meals, inherently differing among manufacturers, varying among batches, and potentially containing mycotoxins, heavy metals, and pesticides. Their plant-based manufacture dictates that chow elevates mouse serum levels of biologically active phytoestrogens to exceed 1,000-50,000 times the level of endogenous estrogen (Brown and Setchell, 2001;Wang et al., 2005), but these are absent in mice fed purified diets and are at less than 5% of that in most humans. Thousands of publications establish that these compounds alter regulatory, signaling, oncogenic, and metabolic pathways that can affect stem cell function.

High-fat diet activates a PPAR-δ program to enhance intestinal stem cell function

“…''chow diet'' as a control diet in stem cell studies (Li et al, 2020). Chow diet is a widely used control diet in DIO studies (Cohen et al, 2014;Softic et al, 2019), including those studying stem cell function in homeostasis and tumorigenesis (Fu et al, 2019), given its wide availability and lower cost compared to purified control diets, a significant concern during longer term (9-14 months) DIO studies.…”