Searchable abstracts of presentations at key conferences in endocrinology

ea0090ep399 | Diabetes, Obesity, Metabolism and Nutrition | ECE2023

Localisation of the steroid 5β-reductase in hepatoma cells

Potter Tom , Tomlinson Jeremy , Gathercole Laura

The hepatic enzyme 5β-reductase (AKR1D1) sits at the interface between two metabolic pathways, converting steroid hormones to their inactive 5β-reduced metabolites during steroid clearance, and as a step in the synthesis of bile acids from cholesterol. Both the steroid substrates and the bile acid products of AKR1D1 are potent hormones that regulate hepatic energy metabolism and inflammation. It is not known how these two functions are spatially organised within hepa...

ea0086p200 | Metabolism, Obesity and Diabetes | SFEBES2022

The American lifestyle-induced obesity syndrome diet (ALIOS) in mice alters the diversity and composition of the gut microbiome

Potter Tom , Arvaniti Anastasia , Harris Shelley , Tomlinson Jeremy , Gathercole Laura

Dysbiosis of the gut microbiome contributes to the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Reduced diversity and composition of the microbiome are associated with increased intestinal barrier permeability, increased bacterial translocation and NAFLD progression. The ALIOS diet in rodents replicates many of the metabolic and histological features of NAFLD in humans and here we report the effect of the ALIOS diet on the gut microbiome. Male and female C57BL/6 ...

ea0081p370 | Diabetes, Obesity, Metabolism and Nutrition | ECE2022

Differential localisation of the A-ring reductases in human hepatocytes: implications for substrate preference and utilisation

Potter Tom , da Conceicao Ismael , Nikolaou Nikolaos , Loh Nellie , Tomlinson Jeremy , Gathercole Laura

The 5-reductases are steroid metabolising enzymes that saturate the C4=C5 bond of the steroid A-ring, and their substrates include androgens, glucocorticoids, and bile acids. 5β-reductases (SRD5A1 & SRD5A2) convert testosterone to the more potent androgen 5β-dihydrotestosterone, and carry out the first step in glucocorticoid clearance, generating 5β-dihydrocortisol from cortisol. 5β-reductase (AKR1D1) is also able to carry out the first step of glucocor...

ea0070aep275 | Diabetes, Obesity, Metabolism and Nutrition | ECE2020

Female AKR1D1 knockout mice have impaired intestinal health with evidence of gut dybiosis, increased gut permeability and an increased incidence of colon cancer

Arvaniti Anastasia , Harris Shelley , Nikolaou Nikolaos , Potter Tom , Cox Roger , Odermatt Alex , Tomlinson Jeremy , Gathercole Laura

Metabolic syndrome (MS) is an important etiologic risk factor for the development and progression of certain cancers, including colorectal. Bile acids (BA) are potent antimicrobials that support gastrointestinal health and the dysregulation of BA homeostasis is thought to contribute to gut dysbiosis and drive endotoxemia. Furthermore, an increase in the cytotoxicity ofintestinal BA species can directly damage enterocytes and promote carcinogenesis. We have previously shown tha...

ea0094p63 | Metabolism, Obesity and Diabetes | SFEBES2023

Androgens potently regulate sterol 12α-hydroxylase (CYP8B1) expression in mouse and human liver

Potter Tom , Gangitano Elena , Visser Jenny , Gathercole Laura , Tomlinson Jeremy , Nikolaou Nikolaos

Polycystic ovarian syndrome (PCOS) is one of the most common endocrine disorders affecting 6-15% of women of reproductive age. The syndrome is characterised by a variety of reproductive and metabolic features, including hyperandrogenism, chronic anovulation and hirsutism as well as insulin resistance, dyslipidaemia, and non-alcoholic fatty liver disease (NAFLD). Specifically regarding NAFLD, androgen excess is hypothesised to have a direct effect on hepatic lipid storage, thus...

ea0094p64 | Metabolism, Obesity and Diabetes | SFEBES2023

Female AKR1D1 knockout mice are protected against diet induced obesity and insulin resistance but not hepatic steatosis

Bailey Maira , Potter Tom , Larner Dean , Morgan Stuart , Lavery Gareth , Tomlinson Jeremy , Gathercole Laura

Bile acids and steroid hormones are potent regulators of metabolic phenotype. 5β-reductase (AKR1D1) is highly expressed in the liver where it catalyses a fundamental step in bile acid synthesis and inactivates steroid hormones. We have previously shown that male, but not female, AKR1D1 knockout (KO) mice on a normal chow diet are leaner than wildtype littermates but are not protected against diet induced obesity. Here we investigate the impact of a high fat diet on female...