Effects of Caffeine on Brown Adipose Tissue Thermogenesis and Metabolic Homeostasis: A Review

Abstract

The impact of brown adipose tissue (BAT) metabolism on understanding energy balance in humans is a relatively new and exciting field of research. The pathogenesis of obesity can be largely explained by an imbalance between caloric intake and energy expenditure, but the underlying mechanisms are far more complex. Traditional non-selective sympathetic activators have been used to artificially elevate energy utilization, or suppress appetite, however undesirable side effects are apparent with the use of these pharmacological interventions. Understanding the role of BAT, in relation to human energy homeostasis has the potential to dramatically offset the energy imbalance associated with obesity. This review discusses paradoxical effects of caffeine on peripheral adenosine receptors and the possible role of adenosine in increasing metabolism is highlighted, with consideration to the potential of central rather than peripheral mechanisms for caffeine mediated BAT thermogenesis and energy expenditure. Research on the complex physiology of adipose tissue, the embryonic lineage and function of the different types of adipocytes is summarized. In addition, the effect of BAT on overall human metabolism and the extent of the associated increase in energy expenditure are discussed. The controversy surrounding the primary β-adrenoceptor involved in human BAT activation is examined, and suggestions as to the lack of translational findings from animal to human physiology and human in vitro to in vivo models are provided. This review compares and distinguishes human and rodent BAT effects, thus developing an understanding of human BAT thermogenesis to aid lifestyle interventions targeting obesity and metabolic syndrome. The focus of this review is on the effect of BAT thermogenesis on overall metabolism, and the potential therapeutic effects of caffeine in increasing metabolism via its effects on BAT.

Dose-Response of Paraxanthine on Cognitive Function: A Double Blind, Placebo Controlled, Crossover Trial

“…Less than half of the population carry the CYP1A2 gene associated with fast metabolism. Some evidence suggest that higher CA intakes increases the risk of insulin resistance [10], high blood pressure [11], and heart attacks [12] in intermediate and slow but not rapid caffeine metabolizers [8] with fast metabolizer seeing greater improvements in athletic performance [13,14] and reduced appetite [15,16].…”

Targeting Melanoma-Initiating Cells by Caffeine: In Silico and In Vitro Approaches

“…This makes it very difficult to discriminate and characterize the pharmacological effects due to the numerous bioactive compounds present in coffee [28]. Caff is one of the bioactive molecules found in most coffees and other beverages that are largely used worldwide, and it has been the subject of extensive investigations to characterize its pharmacological effects, such as neuroprotective action [29] or its role in metabolism [30]. Several studies have reported the anti-neoplastic effects of coffee consumption, for instance, by reducing the risk of hepato-carcinoma and breast cancer in post-menopausal women [26].…”

A review on the potential use of natural products in overweight and obesity

“…Although remains contentious, it is generally accepted that BAT is primarily induced through β3‐adrenoreceptor stimulation. The β3‐adrenoreceptor (β3AR) could cause intracellular cascade in cells, triggering lipolysis, increasing mitochondrial respiration, and activating UCP1 (van Schaik, Kettle, Green, Irving, & Rathner, 2021). Lim et al reported that ginsenoside Rb1 decrease lipid accumulation in vivo and in vitro by inducing the lipolysis–thermogenesis cascade via activation of β3ARs, as β3AR inhibitor treatment decreased the thermogenic effect of Rb1 (Lim et al, 2019).…”