Sulfated Polysaccharides from Enteromorpha prolifera Attenuate Lipid Metabolism Disorders in Mice with Obesity Induced by a High-Fat Diet via a Pathway Dependent on AMP-Activated Protein Kinase

Aili Zhao; Yiqin Chen; Yixin Li; Dai Lin; Zheng Yang; Qi Wang; Hui Chen; Qian Xu; Jie Chen; Pingping Zhu; Fang Huang; Zuxiong Huang; Rendong Ren; Wenting Lin; Wenxiang Wang

doi:10.1093/jn/nxab432

Sulfated Polysaccharides from Enteromorpha prolifera Attenuate Lipid Metabolism Disorders in Mice with Obesity Induced by a High-Fat Diet via a Pathway Dependent on AMP-Activated Protein Kinase

J Nutr. 2022 Apr 1;152(4):939-949. doi: 10.1093/jn/nxab432.

Authors

Aili Zhao^{1

2

3}, Yiqin Chen^{1

2}, Yixin Li¹, Dai Lin^{1

3}, Zheng Yang^{1

3}, Qi Wang^{1

2}, Hui Chen¹, Qian Xu^{1

2}, Jie Chen^{1

3}, Pingping Zhu^{1

3}, Fang Huang^{1

3}, Zuxiong Huang⁴, Rendong Ren^{1

3}, Wenting Lin^{1

3}, Wenxiang Wang^{1

2}

Affiliations

¹ Fujian Province Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou, Fujian Province, China.
² Department of Health Inspection and Quarantine, School of Public Health, Fujian Medical University, Fuzhou, Fujian Province, China.
³ Department of Nutrition and Food Safety, School of Public Health, Fujian Medical University, Fuzhou, Fujian Province, China.
⁴ Department of Hepatology, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou, Fujian Province, China.

PMID: 34958377
DOI: 10.1093/jn/nxab432

Abstract

Background: Obesity-related metabolic diseases have recently evoked worldwide attention. Studies have demonstrated that Enteromorpha polysaccharide (EP) exerts lipid-lowering effects, but the underlying mechanism remains unclear.

Objectives: We investigated whether EP regulates lipid metabolism disorders in mice with high-fat diet (HFD)-induced obesity via an AMP-activated protein kinase (AMPK)-dependent pathway.

Methods: Six-week-old male C57BL/6J mice (18 ± 2 g) were fed a normal diet (ND; 10% energy from fats) or an HFD (60% energy from fats) for 6 weeks to induce obesity and treated intragastrically with EP (200 mg/kg body weight) or distilled water (10 mL/kg body weight) for 8 weeks. Biochemical indicators, AMPK-dependent pathways, and lipid metabolism-related genes were evaluated to assess the effects of EP on HFD-induced lipid metabolism disorders. The essential role of AMPK in the EP-mediated regulation of lipid metabolism was confirmed using HFD-fed male Ampka2-knockout mice (aged 6 weeks; 17 ± 2 g) treated or not treated with the above-mentioned dose of EP. The data were analyzed by t-tests, 2-factor and 1-way ANOVAs.

Results: Compared to the ND, the HFD resulted in a greater body weight (24.3%), perirenal fat index (2.2-fold), and serum total cholesterol (24.66%) and LDL cholesterol (1.25-fold) concentrations (P < 0.05) and dysregulated the AMPK-dependent pathway and the expression of most lipid metabolism-related genes (P < 0.05). Compared to the HFD, EP treatment resulted in a lower perirenal fat index (31.22%) and LDL cholesterol concentration (23.98%) and partly reversed the dysregulation of the AMPK-dependent pathway and the altered expression of lipid metabolism-related genes (P < 0.05). Ampka2 knockout abolished the above-mentioned effects of EP in obese mice and the EP-mediated effects on the expression of lipid metabolism-related genes (P > 0.05).

Conclusions: These findings suggest that EP can ameliorate lipid metabolism disorders in mice with HFD-induced obesity via an AMPK-dependent pathway.

Keywords: Enteromorpha polysaccharide; AMPKα2; high-fat diet; lipid metabolism disorders; obesity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

AMP-Activated Protein Kinases / genetics
AMP-Activated Protein Kinases / metabolism
Animals
Diet, High-Fat* / adverse effects
Lipid Metabolism
Lipid Metabolism Disorders* / drug therapy
Lipid Metabolism Disorders* / etiology
Male
Mice
Mice, Inbred C57BL
Obesity / drug therapy
Obesity / metabolism
Polysaccharides / pharmacology
Sulfates / therapeutic use

Substances

Polysaccharides
Sulfates
AMP-Activated Protein Kinases