1.
Liver fibrosis in the context of nonalcoholic steatohepatitis: the role of adipokines.
DI Maira, G, Pastore, M, Marra, F
Minerva gastroenterologica e dietologica. 2018;(1):39-50
Abstract
Liver fibrosis is a multifaceted process that occurs as a consequence of chronic liver injury. This process is characterized by inflammation, activation of matrix-producing cells, matrix deposition and remodeling, and epithelial cell regeneration. In subjects with chronic liver damage, fibrogenesis is favored by the presence of obesity and insulin resistance, which are also relevant risk factors for the development and progression of nonalcoholic steatohepatitis (NASH). It is now well-known that adipose tissue is not only involved in energy storage but also functions as an endocrine organ that secretes various bioactive substances known as adipokines. This term identifies a group of polypeptide molecules, which exert local, peripheral and/or central actions. Additionally to their well-established role in controlling adipose tissue physiology, energy homeostasis, inflammation and immune function, adipokines have been shown to be involved in different obesity-related diseases, such as hypertension, atherosclerosis and type 2 diabetes. In liver diseases, the biologic actions of these factors may contribute to the mechanisms leading to NASH. In this review, we focus on the role of adipokines in liver fibrogenesis and discuss their potential as regulators of this pathological condition and as targets for future pharmacological treatment strategies of chronic liver diseases.
2.
Adipocytokine Involvement in Innate Immune Mechanisms.
Żelechowska, P, Kozłowska, E, Pastwińska, J, Agier, J, Brzezińska-Błaszczyk, E
Journal of interferon & cytokine research : the official journal of the International Society for Interferon and Cytokine Research. 2018;(12):527-538
Abstract
The innate immune response is defined as an immensely complex and sophisticated process aimed at defending the organism against any disturbance in the body homeostasis, including invading pathogens. It requires a close cooperation of a vast amount of different cell types, recognized as inflammatory migrating cells, as well as stationary cells that form tissues. Moreover, innate immune mechanisms require an efficient functioning of various humoral components that exert a significant impact on physiological and pathological processes. Apart from commonly mentioned humoral factors, this group also includes a family of proteins known as adipocytokines that may act as pro- or anti-inflammatory agents or act both ways. Leptin, predominantly characterized as a proinflammatory adipokine, plays a crucial role in endothelium remodeling and regulation, as well as in cell survival and production of numerous cytokines. Adiponectin, similar to leptin, acts on the endothelial cells and the phagocytic properties of immune cells; however, it exerts an anti-inflammatory impact. Resistin has a documented role in the control of angiogenesis and stimulation of proinflammatory mediator generation and release. Furthermore, there are adipokines, ie, visfatin and chemerin, whose participation in the inflammatory processes is ambiguous. This review focuses on the current knowledge on the extensive role of selected adipokines in innate immune response.
3.
Curcuminoids Plus Piperine Modulate Adipokines in Type 2 Diabetes Mellitus.
Panahi, Y, Khalili, N, Sahebi, E, Namazi, S, Atkin, SL, Majeed, M, Sahebkar, A
Current clinical pharmacology. 2017;(4):253-258
Abstract
OBJECTIVE Curcumin is a naturally occurring polyphenol derived from tumeric that has been reported to have anti-inflammatory properties with effects on adipokine and ghrelin levels. Adiponectin, leptin and ghrelin modulate energy homeostasis but each has modulatory effects on inflammatory cytokines and the immune system. Therefore, this analysis was performed to investigate the effect of curcumin on adiponectin, leptin and ghrelin. METHOD A double blind randomised control trial comparing curcumin 1000mg with 10mg of piperine daily to placebo over a 12 week period. 118 patients with type 2 diabetes were recruited out of which 50 control and 50 active subjects completed the trial. Adiponectin, leptin, ghrelin and tumor necrosis factor-α (TNF-α) were measured at baseline and 12 weeks. RESULTS Between group comparison of the magnitude of changes showed serum levels of leptin (p<0.001), TNF-α (p<0.001) and leptin:adiponectin ratio (p<0.001) to be significantly reduced while serum adiponectin levels were elevated in the curcuminoids versus placebo group (p=0.032). Changes in serum ghrelin levels did not differ between the study groups (p=0.135). CONCLUSION Curcumin supplementation increased adiponectin, whilst the the leptin:adiponectin ratio (a measure of atherosclerosis) and leptin levels were decreased independent of weight change and reflected a decrease in the inflammatory TNF-α levels.