Overview and Introduction: Thematic Review Series on Intestinal Lipid Metabolism

Abstract

The last decade has seen extraordinary advances in our understanding of intestinal lipid metabolism, driven at least in part through attempts to mitigate the ongoing epidemic of obesity and metabolic disease ( 1 ). For example, weight loss strategies including gastric bypass surgery have brought to light unanticipated adaptations in metabolic homeostasis, including altered bile acid signaling and shifts in host-microbial ecology ( 2 ). As a result, our understanding of the role of the intestine in lipid metabolism now includes an expanded role in a range of homeostatic processes, including glucose metabolism, energy utilization, and growth and infl ammation to name but a few. Our Thematic Review Series will selectively cover several of these areas. In particular, we have solicited reviews that summarize a detailed elucidation of the pathways regulating the fl ux of complex lipids across the small intestinal enterocyte, including an emerging role in energy utilization and the role of circadian cues. We have also solicited reviews to provide a thorough understanding of the molecular, genetic, and regulatory pathways involved in modulating intestinal bile acid transport and signaling and new insights into the role of nuclear hormone receptors in the intestine in maintenance of systemic lipid metabolism.In the fi rst article in our series, Eric Yen and his colleagues will review the role and regulation of enterocyte triglyceride synthesis, including the abundantly expressed genes acyl CoA:monoacylglycerol acyltransferase 2 (MGAT2) and acyl CoA:diacylglycerol acyltransferase 1 (ACAT1), whose functions have been examined in numerous model systems and have been shown to play crucial roles in the regulation of fat metabolism and energy utilization. There is heightened interest also in the possibility that these pathways represent druggable targets for obesity and metabolic disorders ( 3 ).In the second article, Mahmood Hussain and Xiaoyue Pan have summarized some of the recent developments in our understanding of the relevance of circadian rhythm to intestinal lipid metabolism. They summarize the role of innate intestinal Clock genes and outline the integration of central signals (via the suprachiasmatic nucleus) with

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Thematic Review of Motivational Factors, Types of Uncertainty, and Entrepreneurship Strategies of Transitional Entrepreneurship among Ethnic Minorities, Immigrants, and Women Entrepreneurs

“…Thematic review/approach is a qualitative research tool often applied for setting the basis for understanding and analyzing trends and happenings in a particular field (Hu 1996;Hargood et al 2008). Thematic review is particularly valuable in organizational sciences and management for the identification, accumulation, evaluation, synthesizing, and reflective interpretation of previous empirical evidence related to a research problem/issue (Rousseau et al 2008;Davidson et al 2012;Davidson 2015). Horn (2010) views TR as a template analysis that analyses text, words, and interviews based on emerging themes and codes identified based on grounded theory insights.…”