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Hepatic Protein Phosphatase 1 Regulatory Subunit 3G Alleviates Obesity and Liver Steatosis by Regulating the Gut Microbiota and Bile Acid Metabolism

Overview
Journal J Pharm Anal
Specialty Chemistry
Date 2024 Sep 12
PMID 39263354
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Abstract

Intestinal dysbiosis and disrupted bile acid (BA) homeostasis are associated with obesity, but the precise mechanisms remain insufficiently explored. Hepatic protein phosphatase 1 regulatory subunit 3G (PPP1R3G) plays a pivotal role in regulating glycolipid metabolism; nevertheless, its obesity-combatting potency remains unclear. In this study, a substantial reduction was observed in serum PPP1R3G levels in high-body mass index (BMI) and high-fat diet (HFD)-exposed mice, establishing a positive correlation between PPP1R3G and non-12α-hydroxylated (non-12-OH) BA content. Additionally, hepatocyte-specific overexpression of (PPP1R3G HOE) mitigated HFD-induced obesity as evidenced by reduced weight, fat mass, and an improved serum lipid profile; hepatic steatosis alleviation was confirmed by normalized liver enzymes and histology. PPP1R3G HOE considerably impacted systemic BA homeostasis, which notably increased the non-12-OH BAs ratio, particularly lithocholic acid (LCA). 16S ribosomal DNA (16S rDNA) sequencing assay indicated that PPP1R3G HOE reversed HFD-induced gut dysbiosis by reducing the / ratio and population, and elevating the relative abundance of , which exhibited a positive correlation with serum LCA levels. A fecal microbiome transplantation test confirmed that the anti-obesity effect of hepatic PPP1R3G was gut microbiota-dependent. Mechanistically, PPP1R3G HOE markedly suppressed hepatic cholesterol 7α-hydroxylase (CYP7A1) and sterol-12α-hydroxylase (CYP8B1), and concurrently upregulated oxysterol 7-α hydroxylase and G protein-coupled BA receptor 5 (TGR5) expression under HFD conditions. Furthermore, LCA administration significantly mitigated the HFD-induced obesity phenotype and elevated non-12-OH BA levels. These findings emphasize the significance of hepatic PPP1R3G in ameliorating diet-induced adiposity and hepatic steatosis through the gut microbiota-BA axis, which may serve as potential therapeutic targets for obesity-related disorders.

References
1.
Erawijantari P, Mizutani S, Shiroma H, Shiba S, Nakajima T, Sakamoto T . Influence of gastrectomy for gastric cancer treatment on faecal microbiome and metabolome profiles. Gut. 2020; 69(8):1404-1415. PMC: 7398469. DOI: 10.1136/gutjnl-2019-319188. View

2.
Sayin S, Wahlstrom A, Felin J, Jantti S, Marschall H, Bamberg K . Gut microbiota regulates bile acid metabolism by reducing the levels of tauro-beta-muricholic acid, a naturally occurring FXR antagonist. Cell Metab. 2013; 17(2):225-35. DOI: 10.1016/j.cmet.2013.01.003. View

3.
Benitez-Paez A, Gomez Del Pugar E, Lopez-Almela I, Moya-Perez A, Codoner-Franch P, Sanz Y . Depletion of Species in the Microbiota of Obese Children Relates to Intestinal Inflammation and Metabolic Phenotype Worsening. mSystems. 2020; 5(2). PMC: 7093825. DOI: 10.1128/mSystems.00857-19. View

4.
Maruyama T, Tanaka K, Suzuki J, Miyoshi H, Harada N, Nakamura T . Targeted disruption of G protein-coupled bile acid receptor 1 (Gpbar1/M-Bar) in mice. J Endocrinol. 2006; 191(1):197-205. DOI: 10.1677/joe.1.06546. View

5.
Chen L, van den Munckhof I, Schraa K, Ter Horst R, Koehorst M, van Faassen M . Genetic and Microbial Associations to Plasma and Fecal Bile Acids in Obesity Relate to Plasma Lipids and Liver Fat Content. Cell Rep. 2020; 33(1):108212. DOI: 10.1016/j.celrep.2020.108212. View