High intensity interval training promotes total and visceral fat mass loss in obese Zucker rats without modulating gut microbiota.

Florie Maillard,Nathalie Boisseau,Yolanda Fernandez Otero,Vivien Chavanelle,Pascal Sirvent,Richard Bonnet,Lydie Combaret,Antoine Sourdrille,Emilie Vazeille,Nicolas Barnich,Pierre Sauvanet,Geoffrey Delcros

doi:10.1371/journal.pone.0214660

Abstract

AimsIncreased visceral adipose tissue and dysbiosis in the overweight and obese promote chronic inflammation. The aim of this study was to compare the effects of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) on the gut-adipose tissue cross-talk in obese Zucker rats.MethodsObese male Zucker rats (n = 36) were divided in three groups: MICT (12m.min-1 for 51min), HIIT (6 sets at 18 m.min-1 for 4min followed by 3min at 10m.min-1) and controls (CONT; no exercise). The animals ran on a treadmill 5 days/week for 10 weeks. Body composition, glycaemic control, lipid profile, inflammation, lipolysis signalling in subcutaneous and visceral adipose tissue, intestinal permeability (tight junctions and plasma lipopolysaccharide binding protein; LBP), and gut microbiota composition were assessed in the three groups.ResultsAfter 10 weeks of exercise, total and epididymal fat mass decreased only in the HIIT group. The α/β adrenergic receptor RNA ratio in subcutaneous adipose tissue increased only in the HIIT group. The expression level of phosphorylated hormone-sensitive lipase was not modified by training. Both HIIT and MICT decreased inflammation (plasma myeloperoxidase and keratinocyte-derived chemokine secretion in adipose tissue) and improved glucose metabolism. Zonula occludens-1 and occludin were upregulated in the HIIT group. Plasma LBP was similarly reduced in both training groups. HIIT and MICT did not affect gut microbiota composition.ConclusionIn obese Zucker rats, HIIT and MICT improved inflammation and glucose metabolism. In contrast, only HIIT decreased total and visceral fat mass. These adaptations were not associated with modifications in gut microbiota composition.

Highlights

Obesity has dramatically increased worldwide in recent decades and is a critical health problem
Only high-intensity interval training (HIIT) decreased total and visceral fat mass. These adaptations were not associated with modifications in gut microbiota composition
After 1 week of treadmill acclimatization, adult Zucker rats were randomly divided in three groups: HIIT (n = 12), moderate-intensity continuous training (MICT) (n = 12) or CONT (n = 12)

Summary

Introduction

Obesity has dramatically increased worldwide in recent decades and is a critical health problem. Obesity is characterized by a low-grade inflammation state [2,3]. Visceral FM is characterized by a greater secretory activity (free fatty acids, TNF-α, IL-6, IL-8, etc.) that promotes insulin resistance, chronic low-grade inflammation and risks of cardiovascular disease [5,6]. Gut microbiota has been recognized as a major actor in pathological conditions associated with obesity and its related complications [7,8]. This relationship was confirmed by increased adiposity in germ-free mice after faecal microbiota transplant from obese mice (ob/ob) [9]. High-fat diets induce dysregulation of intestinal permeability, promoting an increase in plasma lipopolysaccharide (LPS) (i.e., a constituent of Gram-negative bacteria), a condition defined as metabolic endotoxemia [16], and triggering inflammation and insulin resistance [17]

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Results

Conclusion