Proglumide Reverses Nonalcoholic Steatohepatitis by Interaction with the Farnesoid X Receptor and Altering the Microbiome

Abstract

Nonalcoholic steatohepatitis (NASH) is associated with obesity, metabolic syndrome, and dysbiosis of the gut microbiome. Cholecystokinin (CCK) is released by saturated fats and plays an important role in bile acid secretion. CCK receptors are expressed on cholangiocytes, and CCK-B receptor expression increases in the livers of mice with NASH. The farnesoid X receptor (FXR) is involved in bile acid transport and is a target for novel therapeutics for NASH. The aim of this study was to examine the role of proglumide, a CCK receptor inhibitor, in a murine model of NASH and its interaction at FXR. Mice were fed a choline deficient ethionine (CDE) diet to induce NASH. Some CDE-fed mice received proglumide-treated drinking water. Blood was collected and liver tissues were examined histologically. Proglumide’s interaction at FXR was evaluated by computer modeling, a luciferase reporter assay, and tissue FXR expression. Stool microbiome was analyzed by RNA-Sequencing. CDE-fed mice developed NASH and the effect was prevented by proglumide. Computer modeling demonstrated specific binding of proglumide to FXR. Proglumide binding in the reporter assay was consistent with a partial agonist at the FXR with a mean binding affinity of 215 nM. FXR expression was significantly decreased in livers of CDE-fed mice compared to control livers, and proglumide restored FXR expression to normal levels. Proglumide therapy altered the microbiome signature by increasing beneficial and decreasing harmful bacteria. These data highlight the potential novel mechanisms by which proglumide therapy may improve NASH through interaction with the FXR and consequent alteration of the gut microbiome.

Safety and Dosing Study of a Cholecystokinin Receptor Antagonist in Non‐alcoholic Steatohepatitis

“…Proglumide is the only CCK receptor antagonist that increases bile flow 21 and decreases bile acid concentration in animal models; therefore, we studied the interaction of proglumide with FXR using a human luciferase reporter assay and demonstrated that proglumide interacted with FXR as a partial agonist. 42 Since bile acids are affected by the gut microbiome, chronic proglumide therapy in mice also altered the microbiome, rendering it less hepatotoxic and increasing beneficial bacteria species. 42 These reasons are some of the myriad potential mechanisms through which proglumide may interact to decrease NASH.…”

“… 42 Since bile acids are affected by the gut microbiome, chronic proglumide therapy in mice also altered the microbiome, rendering it less hepatotoxic and increasing beneficial bacteria species. 42 These reasons are some of the myriad potential mechanisms through which proglumide may interact to decrease NASH.…”

“…Since proglumide reduces cytokine and chemokine expression in murine NASH livers, 30 proglumide may exert its anti‐inflammatory effects in the liver by cross‐talk with chemokine receptors and reducing cytokines. Proglumide is the only CCK receptor antagonist that increases bile flow 21 and decreases bile acid concentration in animal models; therefore, we studied the interaction of proglumide with FXR using a human luciferase reporter assay and demonstrated that proglumide interacted with FXR as a partial agonist 42 . Since bile acids are affected by the gut microbiome, chronic proglumide therapy in mice also altered the microbiome, rendering it less hepatotoxic and increasing beneficial bacteria species 42 .…”

Molecular mechanisms of metabolic disease-associated hepatic inflammation in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

“…Cholangiocytes are a heterogenous population of epithelial cells that line bile ducts. Cholangiocytes can be activated to participate in hepatic inflammation and regulate liver fibrosis by interacting with myofibroblasts [111]. For example, cholecystokinin (CCK) released by duodenal enteroendocrine I-cells in response to dietary lipids and proteins can activate CCK receptors on cholangiocytes to promote NASH progression.…”

3D-QSAR and Molecular Dynamics Study of Isoxazole Derivatives to Identify the Structural Requirements for Farnesoid X Receptor (FXR) Agonists

“…Numerous FXR agonists that have been developed for the treatment of NAFLD are in preclinical and clinical trials at present. The most advanced FXR agonist in clinical development is obeticholic acid [ 6 , 7 ], which was approved by the US Food and Drug Administration (FDA) for the treatment primary biliary cholangitis (PBC) in 2016, and which is currently being investigated in clinical evaluation for the treatment of NAFLD. Obeticholic acid improves a variety of metabolic characteristics, such as liver steatosis, liver inflammation, and fibrosis [ 8 ].…”