The Break-Fast study protocol: a single arm pre-post study to measure the effect of a protein-rich breakfast on autophagic flux in fasting healthy individuals (original) (raw)

System-wide Benefits of Intermeal Fasting by Autophagy

Cell metabolism, 2017

Autophagy failure is associated with metabolic insufficiency. Although caloric restriction (CR) extends healthspan, its adherence in humans is poor. We established an isocaloric twice-a-day (ITAD) feeding model wherein ITAD-fed mice consume the same food amount as ad libitum controls but at two short windows early and late in the diurnal cycle. We hypothesized that ITAD feeding will provide two intervals of intermeal fasting per circadian period and induce autophagy. We show that ITAD feeding modifies circadian autophagy and glucose/lipid metabolism that correlate with feeding-driven changes in circulating insulin. ITAD feeding decreases adiposity and, unlike CR, enhances muscle mass. ITAD feeding drives energy expenditure, lowers lipid levels, suppresses gluconeogenesis, and prevents age/obesity-associated metabolic defects. Using liver-, adipose-, myogenic-, and proopiomelanocortin neuron-specific autophagy-null mice, we mapped the contribution of tissue-specific autophagy to syst...

Editorial: The Dynamic Interplay Between Nutrition, Autophagy and Cell Metabolism

2021

Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, L’Aquila, Italy, Division of Human Anatomy and Physiopathology, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy, Cell Signaling and Cancer Laboratory, Faculty of Medicine and Health, Leeds Institute of Medical Research, St. James’ University Hospital, University of Leeds, Leeds, United Kingdom

The Combination of Fasting, Acute Resistance Exercise, and Protein Ingestion Led to Different Responses of Autophagy Markers in Gastrocnemius and Liver Samples

Nutrients

The present study verified the responses of proteins related to the autophagy pathway after 10 h of fast with resistance exercise and protein ingestion in skeletal muscle and liver samples. The rats were distributed into five experimental groups: control (CT; sedentary and without gavage after fast), exercise immediately (EXE-imm; after fast, rats were submitted to the resistance protocol and received water by gavage immediately after exercise), exercise after 1 h (EXE-1h; after fast, rats were submitted to the resistance protocol and received water by gavage 1 h after exercise), exercise and supplementation immediately after exercise (EXE/Suppl-imm; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage immediately after exercise), exercise and supplementation 1 h after exercise (EXE/Suppl-1h; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage 1 ...

Altered Autophagy in Human Adipose Tissues in Obesity

Endocrine Reviews, 2010

Kovsan J, Bashan N, Greenberg AS, Rudich A. Potential role of autophagy in modulation of lipid metabolism. Autophagy is a major degradative pathway(s) by which intracellular components are delivered into the lysosomes. It is largely implicated in determining cell death and survival because it eliminates unnecessary, damaged, and/or potentially harmful cellular products and organelles and is an important source for nutrients and energy production under conditions of external nutrient deficiency. As such, autophagy has been suggested to contribute to the regulation of carbohydrate and protein metabolism during fasting. Recently, three papers implicated a role for autophagy in cellular lipid metabolism as well. This Perspectives article presents these novel findings in the context of prior studies on the role of autophagy and lysosomes in metabolic and energy regulation, discusses their points of agreement and opposing propositions, and outlines key outstanding questions.

Anti-oxidative cellular protection effect of fasting-induced autophagy as a mechanism for hormesis

Marine environmental research, 2015

The aim of this investigation was to test the hypothesis that fasting-induced augmented lysosomal autophagic turnover of cellular proteins and organelles will reduce potentially harmful lipofuscin (age-pigment) formation in cells by more effectively removing oxidatively damaged proteins. An animal model (marine snail - common periwinkle, Littorina littorea) was used to experimentally test this hypothesis. Snails were deprived of algal food for 7 days to induce an augmented autophagic response in their hepatopancreatic digestive cells (hepatocyte analogues). This treatment resulted in a 25% reduction in the cellular content of lipofuscin in the digestive cells of the fasting animals in comparison with snails fed ad libitum on green alga (Ulva lactuca). Similar findings have previously been observed in the digestive cells of marine mussels subjected to copper-induced oxidative stress. Additional measurements showed that fasting significantly increased cellular health based on lysosoma...

Important Role of Autophagy in Regulation of Metabolic Processes in Health, Disease and Aging

Physiological Research, 2014

Autophagy is the basic catabolic mechanism that involves degradation of dysfunctional cellular components through the action of lysosome as well as supplying energy and compounds for the synthesis of essential biomacromolecules. This process enables cells to survive stress from the external environment like nutrient deprivation. Autophagy is important in the breakdown of proteins, carbohydrates and lipids as well. Furthermore, recent studies have shown that autophagy is critical in wide range of normal human physiological processes, and defective autophagy is associated with diverse diseases, including lysosomal storage disease, myopathies, neurodegeneration and various metabolic disorders. This review summarizes the most up-to-date findings on what role autophagy plays in metabolism.