Genetically engineered E. coli Nissle attenuates hyperammonemia and prevents memory impairment in bile‐duct ligated rats

Hyperammonemia associated with chronic liver disease (CLD) is implicated in the pathogenesis of hepatic encephalopathy (HE). The gut is a major source of ammonia production that contributes to hyperammonemia in CLD and HE and remains the primary therapeutic target for lowering hyperammonemia. As an ammonia‐lowering strategy, Escherichia coli Nissle 1917 bacterium was genetically modified to consume and convert ammonia to arginine (S‐ARG). S‐ARG was further modified to additionally synthesize butyrate (S‐ARG+BUT). Both strains were evaluated in bile‐duct ligated (BDL) rats; experimental model of CLD and HE. Methods One‐week post‐surgery, BDLs received non‐modified EcN (EcN), S‐ARG, S‐ARG+BUT (3x1011 CFU/day) or vehicle until sacrifice at 3‐ or 5‐weeks. Plasma (ammonia/pro‐inflammatory/liver‐function), liver fibrosis (hydroxyproline), liver mRNA (pro‐inflammatory/fibrogenic/anti‐apoptotic) and colon mRNA (pro‐inflammatory) biomarkers were measured post‐sacrifice. Memory, motor‐coordination, muscle‐strength, and locomotion were assessed at 5‐weeks. Results In BDL‐Veh rats, hyperammonemia developed at 3‐ and further increased at 5‐weeks. This rise was prevented by S‐ARG and S‐ARG+BUT, whereas EcN was ineffective. Memory impairment was prevented only in S‐ARG+BUT vs BDL‐Veh. Systemic inflammation (IL‐10/MCP‐1/endotoxin) increased at 3‐ and 5‐weeks in BDL‐Veh. S‐ARG+BUT attenuated inflammation at both timepoints (except 5‐week endotoxin) vs BDL‐Veh, whereas S‐ARG only attenuated IP‐10 and MCP‐1 at 3‐weeks. Circulating (ALT/AST/ALP/GGT/albumin/bilirubin) and gene expression liver‐function markers (IL‐10/IL‐6/IL‐1β/TGF‐β/α‐SMA/collagen‐1α1/Bcl‐2) were not normalized by either strain. Colonic mRNA (TNF‐α/IL‐1β/occludin) markers were attenuated by synthetic strains at both timepoints vs BDL‐Veh. Conclusion S‐ARG and S‐ARG+BUT attenuated hyperammonemia, with S‐ARG+BUT additional memory protection likely due to greater anti‐inflammatory effect. These innovative strategies, particularly S‐ARG+BUT, have potential to prevent HE

An engineered bacterial therapeutic lowers urinary oxalate in preclinical models and in silico simulations of enteric hyperoxaluria

Abstract Enteric hyperoxaluria (EH) is a metabolic disease caused by excessive absorption of dietary oxalate leading to the formation of chronic kidney stones and kidney failure. There are no approved pharmaceutical treatments for EH. SYNB8802 is an engineered bacterial therapeutic designed to consume oxalate in the gut and lower urinary oxalate as a potential treatment for EH. Oral administration of SYNB8802 leads to significantly decreased urinary oxalate excretion in healthy mice and non‐human primates, demonstrating the strain's ability to consume oxalate in vivo. A mathematical modeling framework was constructed that combines in vitro and in vivo preclinical data to predict the effects of SYNB8802 administration on urinary oxalate excretion in humans. Simulations of SYNB8802 administration predict a clinically meaningful lowering of urinary oxalate excretion in healthy volunteers and EH patients. Together, these findings suggest that SYNB8802 is a promising treatment for EH

Engineered bacteria producing aryl‐hydrocarbon receptor agonists protect against ethanol‐induced liver disease in mice

International audienceBackground and Purpose Gut bacteria metabolize tryptophan into indoles. Intestinal levels of the tryptophan metabolite indole‐3‐acetic acid are reduced in patients with alcohol‐associated hepatitis. Supplementation of indole‐3‐acetic acid protects against ethanol‐induced liver disease in mice. The aim of this study was to evaluate the effect of engineered bacteria producing indoles as Aryl‐hydrocarbon receptor (Ahr) agonists. Methods C57BL/6 mice were subjected to chronic‐plus‐binge ethanol feeding and orally given PBS, control Escherichia coli Nissle 1917 (EcN) or engineered EcN‐Ahr. The effects of EcN and EcN‐Ahr were also examined in mice lacking Ahr in interleukin 22 (Il22)‐producing cells. ResultsThrough the deletion of endogenous genes trpR and tnaA , coupled with over expression of a feedback‐resistant tryptophan biosynthesis operon, EcN‐Ahr were engineered to overproduce tryptophan. Additional engineering allowed conversion of this tryptophan to indoles including indole‐3‐acetic acid and indole‐3‐lactic acid. EcN‐Ahr ameliorated ethanol‐induced liver disease in C57BL/6 mice. EcN‐Ahr upregulated intestinal gene expression of Cyp1a1 , Nrf2 , Il22 , Reg3b , and Reg3g , and increased Il22‐expressing type 3 innate lymphoid cells. In addition, EcN‐Ahr reduced translocation of bacteria to the liver. The beneficial effect of EcN‐Ahr was abrogated in mice lacking Ahr expression in Il22‐producing immune cells. ConclusionsOur findings indicate that tryptophan metabolites locally produced by engineered gut bacteria mitigate liver disease via Ahr‐mediated activation in intestinal immune cells

Discovery of HSD-621 as a Potential Agent for the Treatment of Type 2 Diabetes

11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyzes the conversion of inactive glucocorticoid cortisone to its active form, cortisol. The glucocorticoid receptor (GR) signaling pathway has been linked to the pathophysiology of diabetes and metabolic syndrome. Herein, the structure–activity relationship of a series of piperazine sulfonamide-based 11β-HSD1 inhibitors is described. (<i>R</i>)-3,3,3-Trifluoro-2-(5-(((<i>R</i>)-4-(4-fluoro-2-(trifluoromethyl)­phenyl)-2-methylpiperazin-1-yl)­sulfonyl)­thiophen-2-yl)-2-hydroxypropanamide <b>18a</b> (HSD-621) was identified as a potent and selective 11β-HSD1 inhibitor and was ultimately selected as a clinical development candidate. HSD-621 has an attractive overall pharmaceutical profile and demonstrates good oral bioavailability in mouse, rat, and dog. When orally dosed in C57/BL6 diet-induced obesity (DIO) mice, HSD-621 was efficacious and showed a significant reduction in both fed and fasting glucose and insulin levels. Furthermore, HSD-621 was well tolerated in drug safety assessment studies