Non‑alcoholic fatty liver disease in patients with morbid obesity: the gut microbiota axis as a potential pathophysiology mechanism

Alterations in gut microbiota are associated with the pathogenesis of metabolic diseases, including metabolic-associated fatty liver disease (MAFLD). The aim of this study was to evaluate gut microbiota composition and functionality in patients with morbid obesity with different degrees of MAFLD, as assessed by biopsy.Funding for open Access charge: Universidad de Málaga / CBUA. This work was supported in part by a grant from the Ministry of Health and Families of Junta de Andalucía (PI-0108-2022). (“A way to make Europe”). This study was co-funded by FEDER funds. I.C.-P. was the recipient of a postdoctoral grant (Río Hortega CM 17/00169), and is now the recipient of a post-doctoral grant (Juan Rodes JR 19/00054) from the Instituto de Salud Carlos III and co-funded by Fondo Europeo de Desarrollo Regional-FEDER. L.G.-S. is supported by the Nicolas Monardes program from Consejería de Salud de Andalucía (Spain) (C-0028-2018). C.G.-R. was supported by the Miguel Servet program from the Instituto de Salud Carlos III (CP20/00066)

Lipopolysaccharide and lipopolysaccharide-binding protein levels and their relationship to early metabolic improvement after bariatric surgery

Background: Bariatric surgery usually results in metabolic improvements within a few days from intervention, but the underlying mechanism is not completely understood and may vary depending on the bariatric procedure. Lipopolysaccharides (LPS) from gut microbiota have been proposed as a triggering factor for the inflammatory state in obesity. Roux-en-Y Gastric Bypass (RYGB) leads to a LPS decrease in the medium-term. Objective: To analyze LPS and LPS-binding protein (LBP) in normoglycemic (NG) and diabetic morbidly obese patients in the short-term after 2 different bariatric surgery procedures. Setting: University Hospital, Spain. Methods: Fifty morbidly obese patients underwent bariatric surgery: 24 with sleeve gastrectomy (SG) and 26 with biliopancreatic diversion (BPD). Patients were classified according to their glycemic status as NG or prediabetic/diabetic. LPS and LBP levels and biochemical and anthropometric variables were determined before and at days 15 and 90 after surgery Results: A significant LPS reduction was seen only in the prediabetic/diabetic patients at 90 days after SG. LBP levels rose at 15 days after BPD but at 90 days returned to baseline in both NG and prediabetic/diabetic patients. At 90 days after SG, LBP levels significantly decreased compared to baseline in NG and prediabetic/diabetic patients. After multivariate analysis only the change in BMI was independently associated with the change in LBP levels at 90 days. None of the changes in biochemical or anthropometrical variables were significantly associated with the changes in LPS levels at 15 days or 90 days Conclusion: This is the first study showing that the short-term LPS decrease after bariatric surgery depends on the surgical procedure used as well as on the previous glycemic status of the patient, with SG having the greatest short-term effect on LPS and LBP levels. LBP is closely related to anthropometric variables and may be an inflammatory marker in bariatric surgery patientsMCP was a recipient of a FPU grant (AP2009-4537) from the Ministry of Education (Madrid, Spain), MMRR was a recipient of a fellowship from ISCIII (Rio Hortega CM11/00030), Spanish Ministry of Economy and Competitiveness, (Madrid, Spain) and FC was supported by “Miguel Servet Type II” program (CP13/00023) from the ISCIII, Madrid (Spain). This study was supported by “Centros de Investigación En Red” (CIBER, CB06/03/0018) of the “Instituto de Salud Carlos III” (ISCIII), Madrid (Spain), PI12/02355 from ISCIII, and P11-CTS-08181 from Consejeria de Economia, Innovacion, Ciencia y Empleo (Junta de Andalucía, Spain)