An Integrated View: Neuroadipocrinology of Diabesity

Abstract

ABSTRACT Today’s achievements in systems biology and -omics sciences have facilitated a shift from studying individual molecules and tissues to characterising molecules and cells holistically. In this article, we attempt to discuss the status of a much-needed coherent view that integrates studies on neurobiology and adipobiology, as well as those on diabetes and obesity. Globally, cardiometabolic diseases (atherosclerosis, hypertension, type 2 diabetes mellitus, obesity, diabesity, and metabolic syndrome) are the most prevalent pathologies. In 2000, Astrup and Finer (Obes Rev 1: 57-59) wrote the following: “Since type 2 diabetes is obesity dependent, and obesity is the main aetiogical cause of type 2 diabetes, we propose the term ‘diabesity’ should be adopted.” Arguably, the research field of adipobiology has witnessed three major paradigm shifts since the discovery of leptin, an adipose-derived hormone, in 1994. Various neuroendocrine and neurotrophic factors are included in the growing list of endocrine and paracrine adipose-secreted signaling proteins collectively designated adipokines. These findings open a novel field of research known as neuroadipocrinology, a component of neuroendocrinology. Adipokines, including nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), mediate multiple biological processes, such as food intake, immunity, inflammation, memory, mood, and metabolism. The effects on metabolism involve the maintenance of glucose, lipid and energy homeostasis as well as cardioprotection, neuroprotection, and aging. In this article, we highlight the role of metabotrophic factors (MTF) and the adipose- and nonadipose-derived biomolecules that mediate these effects. Recent results demonstrate that circulating and tissue levels of certain MTFs, e.g., adiponectin, NGF, BDNF, glucagon-like protein-1, sirtuin-1, interleukin- 10, and aquaporin-7, are altered in cardiometabolic diseases, including diabesity. Overall, this may cultivate a novel thinking for diabesity, herein also referred to as Homo diabesus.