Bone marrow adipose tissue-derived stem cell factor mediates metabolic regulation of hematopoiesis.

Hematopoiesis is dynamically regulated by metabolic cues in homeostatic and stressed conditions; however, the cellular and molecular mechanisms mediating the metabolic sensing and regulation remain largely obscure. Bone marrow adipose tissue remodels in various metabolic conditions and has been recently proposed as a niche for hematopoietic stem cells after irradiation. Here, we investigated the role of marrow adipose tissue-derived hematopoietic cytokine stem cell factor in unperturbed hematopoiesis by selectively ablating the Kitl gene from adipocytes and bone marrow stroma cells using Adipoq-Cre and Osx1-Cre, respectively. We found that both Adipoq-Kitl knockout (KO) and Osx1-Kitl KO mice diminished hematopoietic stem and progenitor cells and myeloid progenitors in the bone marrow and developed macrocytic anemia at the steady-state. The composition and differentiation of hematopoietic progenitor cells in the bone marrow dynamically responded to metabolic challenges including high fat diet, ß3-adrenergic activation, thermoneutrality, and aging. However, such responses, particularly within the myeloid compartment, were largely impaired in Adipoq-Kitl KO mice. Our data demonstrate that marrow adipose tissue provides stem cell factor essentially for hematopoiesis both at the steady state and upon metabolic stresses.

Consumer Response to Mechanically Tenderized Beef (MTB) and MTB Labels: An Exploratory Focus Group Study.

In May 2016, labeling of certain nonintact mechanically tenderized beef (MTB) products was mandated in the United States. MTB products should be handled differently by the consumer because pathogens can be transferred from the exterior to the interior of the meat during the tenderization process. Without labeling, it is difficult to visually distinguish between some intact beef and MTB products, which is a concern because MTB products require higher internal cooking temperatures for safety. An exploratory study was conducted to understand consumer understanding of MTB products and consumer responses to the new label. Thirteen focus groups were convened in rural and urban settings across Virginia and North Carolina between December 2015 and May 2016. Sessions were audiorecorded, transcribed verbatim, and analyzed through constant-comparison thematic analysis. Although MTB products were commonly bought, prepared, and consumed, consumer awareness of MTB products and the MTB process was limited. Generally, the label confused participants, and they did not understand the message. Specifically, terminology such as "blade tenderized" and "mechanically tenderized" were preferred over the term "needle tenderized" on labels. Once explained, many individuals wanted more information and better messaging. Through a multiprong approach, other messaging methods (e.g., in stores, through technology, and with certifications) were highly valued by consumers and may result in increased message clarity. Ultimately, the intrinsic and extrinsic properties of the beef rather than the MTB product continued to be the primary guide for purchasing and preparation. This study is the first to be conducted regarding American perceptions of MTB products. An understanding of consumer awareness of MTB products and labels is needed to develop targeted risk messaging communication tools.