Dr Laura Gathercole
Senior Lecturer in Human Physiology
Department of Biological and Medical Sciences

Research
Publications
Journal articles
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Nikolaou N, Gathercole L, Marchand L, Althari S, Dempster N, Green C, van de Bunt M, McNeil C, Arvaniti A, Hughes B, Sgromo B, Gillies R, Marschall H, Penning P, Ryan J, Arlt W, Hodson L, Tomlinson J, 'AKR1D1 is a novel regulator of metabolic phenotype in human hepatocytes and is dysregulated in non-alcoholic fatty liver disease'
Metabolism 99 (2019) pp.67-80
ISSN: 0026-0495AbstractPublished here Open Access on RADARObjective:Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome. Steroidhormones and bile acids are potent regulators of hepatic carbohydrate and lipid metabolism. Steroid 5β-reductase (AKR1D1) is highly expressed in human liver where it inactivates steroid hormones and catalyzes afundamental step in bile acid synthesis.Methods:Human liver biopsies were obtained from 34 obese patients and AKR1D1 mRNA expression levels weremeasured using qPCR. Genetic manipulation of AKR1D1 was performed in human HepG2 and Huh7 liver celllines. Metabolic assessments were made using transcriptome analysis, western blotting, mass spectrometry, clin-ical biochemistry, and enzyme immunoassays.Results:In human liver biopsies,AKR1D1expression decreased with advancing steatosis,fibrosis and inflamma-tion.Expression was decreasedin patients with type 2 diabetes. In human liver cell lines,AKR1D1knockdown de-creased primary bile acid biosynthesis and steroid hormone clearance. RNA-sequencing identified disruption ofkey metabolic pathways, including insulin action and fatty acid metabolism.AKR1D1knockdown increased he-patocyte triglyceride accumulation, insulin sensitivity, and glycogen synthesis, through increasedde novolipo-genesis and decreasedβ-oxidation, fueling hepatocyte inflammation. Pharmacological manipulation of bileacid receptor activation prevented the induction of lipogenic and carbohydrate genes, suggesting that the ob-served metabolic phenotype is driven through bile acid rather than steroid hormone availability.Conclusions:Genetic manipulation of AKR1D1 regulates the metabolic phenotype of human hepatoma cell lines,driving steatosis and inflammation. Taken together, the observation thatAKR1D1mRNA is down-regulated withadvancing NAFLD suggests that it may have a crucial role in the pathogenesis and progression of the disease.
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Crowley RK, Woods CP, Hughes BA, Gray J, McCarthy T, Taylor AE, Gathercole LL, Shackleton CHL, Crabtree N, Arlt W, Stewart PM, Tomlinson JW, 'Increased central adiposity and decreased subcutaneous adipose tissue 11β-hydroxysteroid dehydrogenase type 1 are associated with deterioration in glucose tolerance-A longitudinal cohort study.'
Clinical Endocrinology 91 (1) (2019) pp.72-81
ISSN: 0300-0664 eISSN: 1365-2265AbstractPublished here Open Access on RADARObjective and Context. Increasing adiposity, ageing and tissue‐specific regeneration of cortisol through the activity of 11β‐hydroxysteroid dehydrogenase type 1 have been associated with deterioration in glucose tolerance. We undertook a longitudinal, prospective clinical study to determine if alterations in local glucocorticoid metabolism track with changes in glucose tolerance. Design, Patients, and Measurements. Sixty‐five overweight/obese individuals (mean age 50.3 ± 7.3 years) underwent oral glucose tolerance testing, body composition assessment, subcutaneous adipose tissue biopsy and urinary steroid metabolite analysis annually for up to 5 years. Participants were categorized into those in whom glucose tolerance deteriorated (“deteriorators”) or improved (“improvers”). Results. Deteriorating glucose tolerance was associated with increasing total and trunk fat mass and increased subcutaneous adipose tissue expression of lipogenic genes. Subcutaneous adipose tissue 11β‐HSD1 gene expression decreased in deteriorators, and at study completion, it was highest in the improvers. There was a significant negative correlation between change in area under the curve glucose and 11β‐HSD1 expression. Global 11β‐HSD1 activity did not change and was not different between deteriorators and improvers at baseline or follow‐up. Conclusion. Longitudinal deterioration in metabolic phenotype is not associated with increased 11β‐HSD1 activity, but decreased subcutaneous adipose tissue gene expression. These changes may represent a compensatory mechanism to decrease local glucocorticoid exposure in the face of an adverse metabolic phenotype.
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Woods CP, Crowley RK, Gathercole LL, Hughes B, Gray J, McCarthy T, Crabtree N, Stewart PM, Tomlinson JW, 'Changes in adipose tissue gene expression profile and fat mass are associated with deteriorating glucose tolerance'
Irish Journal of Medical Science 185 (Suppl 7) (2016) pp.372-372
ISSN: 0021-1265Published here -
Larner DP, Morgan SA, Gathercole LL, Doig CL, Guest P, Weston C, Hazeldine J, Tomlinson JW, Stewart PM, Lavery GG, 'Male 11 beta-HSD1 Knockout Mice Fed Trans-Fats and Fructose Are Not Protected From Metabolic Syndrome or Nonalcoholic Fatty Liver Disease'
Endocrinology 157 (9) (2016) pp.3493-3504
ISSN: 0013-7227 eISSN: 1945-7170AbstractNonalcoholic fatty liver disease (NAFLD) defines a spectrum of conditions from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis and is regarded as the hepatic manifestation of the metabolic syndrome. Glucocorticoids can promote steatosis by stimulating lipolysis within adipose tissue, free fatty acid delivery to liver and hepatic de novo lipogenesis. Glucocorticoids can be reactivated in liver through 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD1) enzyme activity. Inhibition of 11 beta-HSD1 has been suggested as a potential treatment for NAFLD. To test this, male mice with global (11 beta-HSD1 knockout [KO]) and liver-specific (LKO) 11 beta-HSD1 loss of function were fed the American Lifestyle Induced Obesity Syndrome (ALIOS) diet, known to recapitulate the spectrum of NAFLD, and metabolic and liver phenotypes assessed. Body weight, muscle and adipose tissue masses, and parameters of glucose homeostasis showed that 11 beta-HSD1KO and LKO mice were not protected from systemic metabolic disease. Evaluation of hepatic histology, triglyceride content, and blinded NAFLD activity score assessment indicated that levels of steatosis were similar between 11 beta-HSD1KO, LKO, and control mice. Unexpectedly, histological analysis revealed significantly increased levels of immune foci present in livers of 11 beta-HSD1KO but not LKO or control mice, suggestive of a transition to NASH. This was endorsed by elevated hepatic expression of key immune cell and inflammatory markers. These data indicate that 11 beta-HSD1-deficient mice are not protected from metabolic disease or hepatosteatosis in the face of a NAFLD-inducing diet. However, global deficiency of 11 beta-HSD1 did increase markers of hepatic inflammation and suggests a critical role for 11 beta-HSD1 in restraining the transition to NASH.Published here -
Gathercole LL, Hazlehurst JM, Armstrong MJ, Crowley R, Boocock S, O'Reilly MW, Round M, Brown R, Bolton S, Cramb R, Newsome PN, Semple RK, Paisey R, Tomlinson JW, Geberhiwot T, 'Advanced non-alcoholic fatty liver disease and adipose tissue fibrosis in patients with Alstrom syndrome'
Liver International 36 (11) (2016) pp.1704-1712
ISSN: 1478-3223 eISSN: 1478-3231AbstractPublished hereBackground and Aims
Alström syndrome (AS) is a recessive monogenic syndrome characterized by obesity, extreme insulin resistance and multi-organ fibrosis. Despite phenotypically being high risk of non-alcoholic fatty liver disease (NAFLD), there is a lack of data on the extent of fibrosis in the liver and its close links to adipose in patients with AS. Our aim was to characterize the hepatic and adipose phenotype in patients with AS.
Methods
Observational cohort study with comprehensive assessment of metabolic liver phenotype including liver elastography (Fibroscan®), serum Enhanced Liver Fibrosis (ELF) Panel and liver histology. In addition, abdominal adipose histology and gene expression was assessed. We recruited 30 patients from the UK national AS clinic. A subset of six patients underwent adipose biopsies which was compared with control tissue from nine healthy participants.
Results
Patients were overweight/obese (BMI 29.3 (25.95–34.05) kg/m2). A total of 80% (24/30) were diabetic; 74% (20/27) had liver ultrasound scanning suggestive of NAFLD. As judged by the ELF panel, 96% (24/25) were categorized as having fibrosis and 10/21 (48%) had liver elastography consistent with advanced liver fibrosis/cirrhosis. In 7/8 selected cases, there was evidence of advanced NAFLD on liver histology. Adipose tissue histology showed marked fibrosis as well as disordered pro-inflammatory and fibrotic gene expression profiles.
Conclusions
NAFLD and adipose dysfunction are common in patients with AS. The severity of liver disease in our cohort supports the need for screening of liver fibrosis in AS.
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Armstrong MJ, Hull D, Guo K, Barton D, Hazlehurst JM, Gathercole LL, Nasiri M, Yu JL, Gough SC, Newsome PN, Tomlinson JW, 'Glucagon-like peptide 1 decreases lipotoxicity in non-alcoholic steatohepatitis'
Journal of Hepatology 64 (2) (2015) pp.399-408
ISSN: 0168-8278 eISSN: 1600-0641AbstractPublished hereBackground & Aims
Insulin resistance and lipotoxicity are pathognomonic in non-alcoholic steatohepatitis (NASH). Glucagon-like peptide-1 (GLP-1) analogues are licensed for type 2 diabetes, but no prospective experimental data exists in NASH. This study determined the effect of a long-acting GLP-1 analogue, liraglutide, on organ-specific insulin sensitivity, hepatic lipid handling and adipose dysfunction in biopsy-proven NASH.
Methods
Fourteen patients were randomised to 1.8 mg liraglutide or placebo for 12-weeks of the mechanistic component of a double-blind, randomised, placebo-controlled trial (ClinicalTrials.gov-NCT01237119). Patients underwent paired hyperinsulinaemic euglycaemic clamps, stable isotope tracers, adipose microdialysis and serum adipocytokine/metabolic profiling. In vitro isotope experiments on lipid flux were performed on primary human hepatocytes.
Results
Liraglutide reduced BMI (−1.9 vs. +0.04 kg/m2; p
Conclusions
Liraglutide reduces metabolic dysfunction, insulin resistance and lipotoxicity in the key metabolic organs in the pathogenesis of NASH. Liraglutide may offer the potential for a disease-modifying intervention in NASH.
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Nasiri M, Nikolaou N, Parajes S, Krone NP, Valsamakis G, Mastorakos G, Hughes B, Taylor A, Bujalska IJ, Gathercole LL, Tomlinson JW, '5 alpha-Reductase Type 2 Regulates Glucocorticoid Action and Metabolic Phenotype in Human Hepatocytes'
Endocrinology 156 (8) (2015) pp.2863-2871
ISSN: 0013-7227AbstractGlucocorticoids and androgens have both been implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD); androgen deficiency in males, androgen excess in females, and glucocorticoid excess in both sexes are associated with NAFLD. Glucocorticoid and androgen action are regulated at a prereceptor level by the enzyme 5 alpha-reductase type 2 (SRD5A2), which inactivates glucocorticoids to their dihydrometabolites and converts T to DHT. We have therefore explored the role of androgens and glucocorticoids and their metabolism by SRD5A2 upon lipid homeostasis in human hepatocytes. In both primary human hepatocytes and human hepatoma cell lines, glucocorticoids decreased de novo lipogenesis in a dose-dependent manner. Whereas androgen treatment (T and DHT) increased lipogenesis in cell lines and in primary cultures of human hepatocytes from female donors, it was without effect in primary hepatocyte cultures from men. SRD5A2 overexpression reduced the effects of cortisol to suppress lipogenesis and this effect was lost following transfection with an inactive mutant construct. Conversely, pharmacological inhibition using the 5 alpha-reductase inhibitors finasteride and dutasteride augmented cortisol action. We have demonstrated that manipulation of SRD5A2 activity can regulate lipogenesis in human hepatocytes in vitro. This may have significant clinical implications for those patients prescribed 5 alpha-reductase inhibitors, in particular augmenting the actions of glucocorticoids to modulate hepatic lipid flux.Published here -
Morgan SA, McCabe EL, Gathercole LL, Hassan-Smith ZK, Larner DP, Bujalska IJ, Stewart PM, Tomlinson JW, Lavery GG, '11 beta-HSD1 is the major regulator of the tissue-specific effects of circulating glucocorticoid excess'
Proceedings of the National Academy of Sciences 111 (24) (2014) pp.E2482-E2491
ISSN: 1091-6490AbstractThe adverse metabolic effects of prescribed and endogenous glucocorticoid (GC) excess, Cushing syndrome, create a significant health burden. We found that tissue regeneration of GCs by 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD1), rather than circulating delivery, is critical to developing the phenotype of GC excess; 11 beta-HSD1 KO mice with circulating GC excess are protected from the glucose intolerance, hyperinsulinemia, hepatic steatosis, adiposity, hypertension, myopathy, and dermal atrophy of Cushing syndrome. Whereas liver-specific 11 beta-HSD1 KO mice developed a full Cushingoid phenotype, adipose-specific 11 beta-HSD1 KO mice were protected from hepatic steatosis and circulating fatty acid excess. These data challenge our current view of GC action, demonstrating 11 beta-HSD1, particularly in adipose tissue, is key to the development of the adverse metabolic profile associated with circulating GC excess, offering 11 beta-HSD1 inhibition as a previously unidentified approach to treat Cushing syndrome.Published here -
McNelis JC, Manolopoulos KN, Gathercole LL, Bujalska IJ, Stewart PM, Tomlinson JW, Arlt W, 'Dehydroepiandrosterone exerts antiglucocorticoid action on human preadipocyte proliferation, differentiation, and glucose uptake'
AJP - Endocrinology and Metabolism 305 (9) (2013) pp.E1134-E1144
ISSN: 0193-1849AbstractGlucocorticoids increase adipocyte proliferation and differentiation, a process underpinned by the local reactivation of inactive cortisone to active cortisol within adipocytes catalyzed by 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD1). The adrenal sex steroid precursor dehydroepiandrosterone (DHEA) has been shown to inhibit 11 beta-HSD1 in murine adipocytes; however, rodent adrenals do not produce DHEA physiologically. Here, we aimed to determine the effects and underlying mechanisms of the potential antiglucocorticoid action of DHEA and its sulfate ester DHEAS in human preadipocytes. Utilizing a human subcutaneous preadipocyte cell line, Chub-S7, we examined the metabolism and effects of DHEA in human adipocytes, including adipocyte proliferation, differentiation, 11 beta-HSD1 expression, and activity and glucose uptake. DHEA, but not DHEAS, significantly inhibited preadipocyte proliferation via cell cycle arrest in the G1 phase independent of sex steroid and glucocorticoid receptor activation. 11 beta-HSD1 oxoreductase activity in differentiated adipocytes was inhibited by DHEA. DHEA coincubated with cortisone significantly inhibited preadipocyte differentiation, which was assessed by the expression of markers of early (LPL) and terminal (G3PDH) adipocyte differentiation. Coincubation with cortisol, negating the requirement for 11 beta-HSD1 oxoreductase activity, diminished the inhibitory effect of DHEA. Further consistent with glucocorticoid-opposing effects of DHEA, insulin-independent glucose uptake was significantly enhanced by DHEA treatment. DHEA increases basal glucose uptake and inhibits human preadipocyte proliferation and differentiation, thereby exerting an antiglucocorticoid action. DHEA inhibition of the amplification of glucocorticoid action mediated by 11 beta-HSD1 contributes to the inhibitory effect of DHEA on human preadipocyte differentiation.Published here -
Morgan SA, Gathercole LL, Simonet C, Hassan-Smith ZK, Bujalska I, Guest P, Abrahams L, Smith DM, Stewart PM, Lavery GG, Tomlinson JW, 'Regulation of Lipid Metabolism by Glucocorticoids and 11 beta-HSD1 in Skeletal Muscle'
Endocrinology 154 (7) (2013) pp.2374-2384
ISSN: 0013-7227AbstractThe prevalences of insulin resistance and type 2 diabetes mellitus are rising dramatically, and, as a consequence, there is an urgent need to understand the pathogenesis underpinning these conditions to develop new and more efficacious treatments. We have tested the hypothesis that glucocorticoid (GC)-mediated changes in insulin sensitivity may be associated with changes in lipid flux. Furthermore, prereceptor modulation of GC availability by 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta -HSD1) may represent a critical regulatory step. Dexamethasone (DEX) decreased lipogenesis in both murine C2C12 and human LHC-NM2 myotubes. Inactivating p-Ser-79/218 of acetyl-CoA carboxylase 1/2 and activating p-Thr-172 of AMP-activated protein kinase were both increased after DEX treatment in C2C12 myotubes. In contrast, DEX increased beta-oxidation. Selective 11 beta-HSD1 inhibition blocked the 11-dehydrocorticosterone (11DHC)-mediated decrease in lipogenic gene expression and increase in lipolytic gene expression. Lipogenic gene expression was decreased, whereas lipolytic and beta-oxidative gene expression increased in corticosterone (CORT)and 11DHC-treated wild-type mice and CORT (but not 11DHC)-treated 11 beta-HSD1(-/-) mice. Furthermore, CORT-and 11DHC-treated wild-type mice and CORT (but not 11DHC)-treated 11 beta-HSD1(-/-) mice had increased p-Ser-79/218 acetyl-CoA carboxylase 1/2, p-Thr-172 AMP-activated protein kinase and intramyocellular diacylglyceride content. In summary, we have shown that GCs have potent actions on intramyocellular lipid homeostasis by decreasing lipid storage, increasing lipid mobilization and utilization, and increasing diacylglyceride content. It is plausible that dysregulated intramyocellular lipid metabolism may underpin GC-induced insulin resistance of skeletal muscle. (Endocrinology 154: 2374-2384, 2013)Published here -
Hazlehurst JM, Gathercole LL, Nasiri M, Armstrong MJ, Borrows S, Yu JL, Wagenmakers AJM, Stewart PM, Tomlinson JW, 'Glucocorticoids Fail to Cause Insulin Resistance in Human Subcutaneous Adipose Tissue In Vivo'
The Journal of Clinical Endocrinology & Metabolism 98 (4) (2013) pp.1631-1640
ISSN: 0021-972XAbstractPublished hereContext:
It is widely believed that glucocorticoids cause insulin resistance in all tissues. We have previously demonstrated that glucocorticoids cause insulin sensitization in human adipose tissue in vitro and induce insulin resistance in skeletal muscle.
Objective:
Our aim was to determine whether glucocorticoids have tissue-specific effects on insulin sensitivity in vivo.
Design:
Fifteen healthy volunteers were recruited into a double-blind, randomized, placebo-controlled, crossover study, receiving both an overnight hydrocortisone and saline infusion. The tissue-specific actions of insulin were determined using paired 2-step hyperinsulinemic euglycemic clamps incorporating stable isotopes with concomitant adipose tissue microdialysis.
Setting:
The study was performed in the Wellcome Trust Clinical Research Facility, Queen Elizabeth Hospital, Birmingham, United Kingdom.
Main Outcome Measures:
The sensitivity of sc adipose tissue to insulin action was measured.
Results:
Hydrocortisone induced systemic insulin resistance but failed to cause sc adipose tissue insulin resistance as measured by suppression of adipose tissue lipolysis and enhanced insulin-stimulated pyruvate generation. In primary cultures of human hepatocytes, glucocorticoids increased insulin-stimulated p-ser473akt/protein kinase B. Similarly, glucocorticoids enhanced insulin-stimulated p-ser473akt/protein kinase B and increased Insulin receptor substrate 2 mRNA expression in sc, but not omental, intact human adipocytes, suggesting a depot-specificity of action.
Conclusions:
This study represents the first description of sc adipose insulin sensitization by glucocorticoids in vivo and demonstrates tissue-specific actions of glucocorticoids to modify insulin action. It defines an important advance in our understanding of the actions of both endogenous and exogenous glucocorticoids and may have implications for the development and targeting of future glucocorticoid therapies.
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Lavery GG, Zielinska AE, Gathercole LL, Hughes B, Semjonous N, Guest P, Saqib K, Sherlock M, Reynolds G, Morgan SA, Tomlinson JW, Walker EA, Rabbitt EH, Stewart PM, 'Lack of Significant Metabolic Abnormalities in Mice with Liver-Specific Disruption of 11 beta-Hydroxysteroid Dehydrogenase Type 1'
Endocrinology 153 (7) (2012) pp.3236-3248
ISSN: 0013-7227AbstractGlucocorticoids (GC) are implicated in the development of metabolic syndrome, and patients with GC excess share many clinical features, such as central obesity and glucose intolerance. In patients with obesity or type 2 diabetes, systemic GC concentrations seem to be invariably normal. Tissue GC concentrations determined by the hypothalamic-pituitary-adrenal (HPA) axis and local cortisol (corticosterone in mice) regeneration from cortisone (11-dehydrocorticosterone in mice) by the 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD1) enzyme, principally expressed in the liver. Transgenic mice have demonstrated the importance of 11 beta-HSD1 in mediating aspects of the metabolic syndrome, as well as HPA axis control. In order to address the primacy of hepatic 11 beta-HSD1 in regulating metabolism and the HPA axis, we have generated liver-specific 11 beta-HSD1 knockout (LKO) mice, assessed biomarkers of GC metabolism, and examined responses to high-fat feeding. LKO mice were able to regenerate cortisol from cortisone to 40% of control and had no discernible difference in a urinary metabolite marker of 11 beta-HSD1 activity. Although circulating corticosterone was unaltered, adrenal size was increased, indicative of chronic HPA stimulation. There was a mild improvement in glucose tolerance but with insulin sensitivity largely unaffected. Adiposity and body weight were unaffected as were aspects of hepatic lipid homeostasis, triglyceride accumulation, and serum lipids. Additionally, no changes in the expression of genes involved in glucose or lipid homeostasis were observed. Liver-specific deletion of 11 beta-HSD1 reduces corticosterone regeneration and may be important for setting aspects of HPA axis tone, without impacting upon urinary steroid metabolite profile. These discordant data have significant implications for the use of these biomarkers of 11 beta-HSD1 activity in clinical studies. The paucity of metabolic abnormalities in LKO points to important compensatory effects by HPA activation and to a crucial role of extrahepatic 11 beta-HSD1 expression, highlighting the contribution of cross talk between GC target tissues in determining metabolic phenotype. (Endocrinology 153: 3236-3248, 2012)Published here -
McGee KC, Shahmanesh M, Boothby M, Nightingale P, Gathercole LL, Tripathi G, Harte AL, Shojaee-Moradie F, Umpleby AM, Das S, Al-Daghri NM, McTernan PG, Tomlinson JW, 'Evidence for a shift to anaerobic metabolism in adipose tissue in efavirenz-containing regimens for HIV with different nucleoside backbones'
Antiviral Therapy 17 (2012) pp.495-507
ISSN: 1359-6535AbstractPublished hereBackground: Antiretroviral (ARV) treatment has been associated with abnormalities in lipid and mitochondrial metabolism. We compared patterns of gene expression in the subcutaneous adipose tissue (SAT) of HIV-positive subjects before and after 18–24 months of ARV therapy with HIV-negative controls.
Methods: HIV patients naive to ARV were randomized to receive zidovudine (AZT), lamivudine (3TC) with efavirenz (EFV) or tenofovir disoproxil fumarate (TDF) with emtricitabine (FTC) and EFV. Healthy controls (n=15) were matched for age, ethnicity and gender. Patients on a regimen containing abacavir (ABC), 3TC and EFV for 18–24 months were also tested. Genes involved in adipocyte glucocorticoid, lipid and mitochondrial metabolism, and adipocyte differentiation, were profiled with real-time PCR.
Results: AZT led to increased visceral adipose tissue (VAT; P=0.012) and VAT:SAT ratio (P=0.036), whereas TDF increased SAT (P=0.047) and peripheral fat/lean body mass ratio (P=0.017). HIV treatment-naive patients had lower plasma lipoprotein lipase (LPL) activity (P=0.0001) versus controls (remaining below controls after ARV; P=0.038–0.0001). The overall pattern of gene expression was similar across all treatment groups, being most marked with AZT and least with TDF. There was up-regulation of peroxisome proliferator-activated receptor-γ coactivator-1α, uncoupling protein-2 and hexose 6-phosphate dehydrogenase, and down-regulation of nuclear respiratory factor-1, cytochrome oxidase B, cytochrome c oxidase-4, uncoupling protein-3, 11β-hydroxysteroid dehydrogenase type-1, glucocorticoid receptor-α, fatty acid synthase, fatty acid binding protein-4, LPL and hormone sensitive lipase (18–24 months post-treatment versus pretreatment levels and controls; P<0.05 to <0.0001).
Conclusions: The decreased expression of genes involved in lipid and mitochondrial metabolism 18–24 months post-ARV treatment in SAT of HIV patients, in conjunction with the increase in uncoupling protein-2 and decrease in cytochrome oxidase B gene expression, provides evidence of mitochondrial dysfunction and a shift to anaerobic metabolism within SAT in EFV-containing ARV regimens.
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Gathercole LL, Morgan SA, Bujalska IJ, Hauton D, Stewart PM, Tomlinson JW, 'Regulation of lipogenesis by glucocorticoids and insulin in human adipose tissue'
PLoS ONE 6 (10) (2011)
ISSN: 1932-6203AbstractPatients with glucocorticoid (GC) excess, Cushing's syndrome, develop a classic phenotype characterized by central obesity and insulin resistance. GCs are known to increase the release of fatty acids from adipose, by stimulating lipolysis, however, the impact of GCs on the processes that regulate lipid accumulation has not been explored. Intracellular levels of active GC are dependent upon the activity of 11 beta-Hydroxysteroid dehydrogenase type 1 (11 beta-HSD1) and we have hypothesized that 11 beta-HSD1 activity can regulate lipid homeostasis in human adipose tissue (Chub-S7 cell line and primary cultures of human subcutaneous (sc) and omental (om) adipocytes. Across adipocyte differentiation, lipogenesis increased whilst beta-oxidation decreased. GC treatment decreased lipogenesis but did not alter rates of beta-oxidation in Chub-S7 cells, whilst insulin increased lipogenesis in all adipocyte cell models. Low dose Dexamethasone pre-treatment (5 nM) of Chub-S7 cells augmented the ability of insulin to stimulate lipogenesis and there was no evidence of adipose tissue insulin resistance in primary sc cells. Both cortisol and cortisone decreased lipogenesis; selective 11 beta-HSD1 inhibition completely abolished cortisone-mediated repression of lipogenesis. GCs have potent actions upon lipid homeostasis and these effects are dependent upon interactions with insulin. These in vitro data suggest that manipulation of GC availability through selective 11 beta-HSD1 inhibition modifies lipid homeostasis in human adipocytes.Published here -
Gathercole LL, Morgan SA, Bujalska IJ, Stewart PM, Tomlinson JW, 'Short- and long-term glucocorticoid treatment enhances insulin signalling in human subcutaneous adipose tissue'
Nutrition and Diabetes 1 (2011)
ISSN: 2044-4052AbstractPublished hereBackground: Endogenous or exogenous glucocorticoid (GC) excess (Cushing's syndrome) is characterized by increased adiposity and insulin resistance. Although GCs cause global insulin resistance in vivo, we have previously shown that GCs are able to augment insulin action in human adipose tissue, contrasting with their action in skeletal muscle. Cushing's syndrome develops following chronic GC exposure and, in addition, is a state of hyperinsulinemia.
Objectives: We have therefore compared the impact of short- (24 h) and long-term (7 days) GC administration on insulin signalling in differentiated human adipocytes in the presence of low or high concentrations of insulin.
Results: Both short- (24 h) and long-term (7 days) treatment of chub-s7 cells with dexamethasone (Dex) (0.5 μm) increased insulin-stimulated pTyr612IRS1 and pSer473akt/PKB, consistent with insulin sensitization. Chronic high-dose insulin treatment induced insulin resistance in chub-s7 cells. However, treatment with both high-dose insulin and Dex in combination still caused insulin sensitization.
Conclusions: In this human subcutaneous adipocyte cell line, prolonged GC exposure, even in the presence of high insulin concentrations, is able to cause insulin sensitization. We suggest that this is an important mechanism driving adipogenesis and contributes to the obese phenotype of patients with Cushing's syndrome.
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Gathercole LL, Stewart PM, 'Targeting the pre-receptor metabolism of cortisol as a novel therapy in obesity and diabetes'
Journal of Steroid Biochemistry and Molecular Biology 122 (1-3) (2010) pp.21-27
ISSN: 0960-0760AbstractDue to its impact upon health and the economy, the mechanisms that contribute to the pathogenesis of obesity and the metabolic syndrome are under intense scrutiny. In addition to understanding the pathogenesis of disease it is important to design and trial novel therapies. Patients with cortisol excess. Cushing's syndrome, have a phenotype similar to that of the metabolic syndrome and as a result there is much interest the manipulation of glucocorticoid (GC) action as a therapeutic strategy. Intracellular GC levels are regulated by 11 beta-hydroxysteriod dehydrogenase (11 beta-HSD1) which converts inactive cortisone to cortisol, thereby increasing local GC action. There is an abundance of data implicating 11 beta-HSD1 in the pathogenesis of obesity, type 2 diabetes and the metabolic syndrome and 11 beta-HSD1 is an attractive therapeutic target. Selective 11 beta-HSD1 inhibitors, which do not act upon 11 beta-HSD2 (which inactivates cortisol to cortisone) are in development. So far studies have primarily been carried out in rodents, with results showing improvements in metabolic profile. Data are now beginning to emerge from human studies and the results are promising. (c) 2010 Elsevier Ltd. All rights reserved.Published here -
Tomlinson JW, Durrani OM, Bujalska IJ, Gathercole LL, Tomlins PJ, Reuser TTQ, Rose GE, Curnow SJ, Stewart PM, Walker EA, Rauz S, 'The Role of 11 beta-Hydroxysteroid Dehydrogenase 1 in Adipogenesis in Thyroid-Associated Ophthalmopathy'
The Journal of Clinical Endocrinology & Metabolism 95 (1) (2010) pp.398-406
ISSN: 0021-972XAbstractPublished hereContext: Thyroid-associated ophthalmopathy (TAO) is a sight-threatening autoimmune disease in which de novo adipogenesis has been identified as a fundamental pathogenic mechanism. 11β-Hydroxysteroid dehydrogenase 1 (11β-HSD1) increases cortisol bioavailability and is pivotal in mediating glucocorticoid responses in adipose tissue and inflammation.
Objective: In this study we characterize 11β-HSD1 as a determinant of the adipogenic and inflammatory pathways in TAO orbital fat (OF) compared with normal OF.Patients and Methods: OF was harvested from 46 TAO and 44 control patients undergoing orbital surgery. Samples were examined by a combination of immunohistochemistry, real-time RT-PCR, primary cell culture, specific enzyme assays, colorimetric proliferation assays, and bead-based ELISA.
Results: Glucocorticoid (glucocorticoid receptor-α,11β-HSD1, hexose-6-phosphate dehydrogenase) and inflammatory cytokines (IL-1β, IL-1 receptor, IL-6, TNF-α, TNF-α inductible protein, TGF-β2) target genes together with markers of late adipocyte differentiation (fatty-acid-binding-protein-4, glycerol-6-phosphate-dehydrogenase) were highly expressed in TAO whole OF (P < 0.05) compared with controls. Primary cultures of TAO OF stromal cells demonstrated greater 11β-HSD1 oxoreductase activity (P < 0.05), which was regulated by cytokines, most notably TNF-α (P < 0.01), compared with controls. Activity increased across differentiation, and this was most marked in TAO cells (P < 0.01). Similarly, stromal cell proliferation was limited by incubation with cortisol in TAO cells only. Furthermore, cortisone decreased IL-6 (P < 0.005), IL-8 (P < 0.05), and macrophage chemoattractant protein-1 (P < 0.05) production by cultured TAO cells only, an effect that was abrogated by inhibition of 11β-HSD1.
Conclusions: Induction of 11β-HSD1 activity and expression by inflammatory cytokines (TNF-α, IL-6) may enhance orbital adipocyte differentiation (adipogenesis) and limit proliferation in TAO. 11β-HSD1 may also have a role in regulating the local orbital inflammatory response. -
Morgan SA, Sherlock M, Gathercole LL, Lavery GG, Lenaghan C, Bujalska IJ, Laber D, Yu A, Convey G, Mayers R, Hegyi K, Sethi JK, Stewart PM, Smith DM, Tomlinson JW, '11 beta-Hydroxysteroid Dehydrogenase Type 1 Regulates Glucocorticoid-Induced Insulin Resistance in Skeletal Muscle'
Diabetes 58 (11) (2009) pp.2506-2515
ISSN: 0012-1797AbstractPublished hereOBJECTIVE Glucocorticoid excess is characterized by increased adiposity, skeletal myopathy, and insulin resistance, but the precise molecular mechanisms are unknown. Within skeletal muscle, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts cortisone (11-dehydrocorticosterone in rodents) to active cortisol (corticosterone in rodents). We aimed to determine the mechanisms underpinning glucocorticoid-induced insulin resistance in skeletal muscle and indentify how 11β-HSD1 inhibitors improve insulin sensitivity.
RESEARCH DESIGN AND METHODS Rodent and human cell cultures, whole-tissue explants, and animal models were used to determine the impact of glucocorticoids and selective 11β-HSD1 inhibition upon insulin signaling and action.
RESULTS Dexamethasone decreased insulin-stimulated glucose uptake, decreased IRS1 mRNA and protein expression, and increased inactivating pSer307 insulin receptor substrate (IRS)-1. 11β-HSD1 activity and expression were observed in human and rodent myotubes and muscle explants. Activity was predominantly oxo-reductase, generating active glucocorticoid. A1 (selective 11β-HSD1 inhibitor) abolished enzyme activity and blocked the increase in pSer307 IRS1 and reduction in total IRS1 protein after treatment with 11DHC but not corticosterone. In C57Bl6/J mice, the selective 11β-HSD1 inhibitor, A2, decreased fasting blood glucose levels and improved insulin sensitivity. In KK mice treated with A2, skeletal muscle pSer307 IRS1 decreased and pThr308 Akt/PKB increased. In addition, A2 decreased both lipogenic and lipolytic gene expression.
CONCLUSIONS Prereceptor facilitation of glucocorticoid action via 11β-HSD1 increases pSer307 IRS1 and may be crucial in mediating insulin resistance in skeletal muscle. Selective 11β-HSD1 inhibition decreases pSer307 IRS1, increases pThr308 Akt/PKB, and decreases lipogenic and lipolytic gene expression that may represent an important mechanism underpinning their insulin-sensitizing action.
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Boothby M, McGee KC, Tomlinson JW, Gathercole LL, McTernan PG, Shojaee-Moradie F, Umpleby AM, Nightingale P, Shahmanesh M, 'Adipocyte differentiation, mitochondrial gene expression and fat distribution: differences between zidovudine and tenofovir after 6 months'
Antiviral Therapy 14 (2009) pp.1089-1100
ISSN: 1359-6535AbstractPublished hereBackground: Abnormal lipid metabolism and cell oxidative mechanisms are reported in patients on antiretroviral treatment. We compared the expression of several key adipocyte genes in HIV-infected patients randomized to antiretroviral regimens containing zidovudine (AZT) or tenofovir disoproxil fumarate (TDF).
Methods: Subcutaneous fat was sampled from 32 HIV-positive treatment-naive patients before and 6 months after randomization to AZT/lamivudine/efavirenz (n=15) or TDF/emtricitabine/efavirenz (n=17) plus 15 HIV-negative matched controls. Expression of genes involved in adipocyte differentiation, lipid metabolism, mitochondrial function and glucocorticoid generation were profiled using real-time PCR. Lipoprotein lipase and hepatic lipase activity were assessed.
Results: Before treatment, 11β-hydroxysteroid dehydrogenase expression was down-regulated compared with controls. Following 6 months treatment with AZT, there was a significant increase in visceral adipose tissue (VAT; P=0.02) and the ratio of VAT to subcutaneous adipose tissue (P=0.008), down-regulation of cytochrome B (P=0.003) and cytochrome oxidase (COX)-3 gene expression (P=0.03), up-regulation of NADH dehydrogenase (P=0.008) and nuclear-encoded COX-4 (complex IV) gene expression (P=0.012). Genes involved with adipocyte cortisol generation, fatty acid metabolism and the tricarboxylic acid cycle were up-regulated. In the TDF-treated patients, there was no significant change in regional body fat or mitochondrial genes compared with pretreatment values. Changes in the expression of genes involved with cortisol and fatty acid metabolism were less marked with TDF.
Conclusions: Interference with the mitochondrial electron transport chain appears to occur early in an AZT-containing regimen and occurs at a time when there is increased visceral fat and up-regulation of genes involved with adipocyte differentiation and fatty acid flux.
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Bujalska IJ, Gathercole LL, Tomlinson JW, Darimont C, Ermolieff J, Fanjul AN, Rejto PA, Stewart PM, 'A novel selective 11 beta-hydroxysteroid dehydrogenase type 1 inhibitor prevents human adipogenesis'
Journal of Endocrinology 197 (2008) pp.297-307
ISSN: 0022-0795AbstractGlucocorticoid excess increases fat mass, preferentially within omental depots; yet circulating cortisol concentrations are normal in most patients with metabolic syndrome (MS). At a pre-receptor level, 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD1) activates cortisol from cortisone locally within adipose tissue, and inhibition of 11 beta-HSD1 in liver and adipose tissue has been proposed as a novel therapy to treat MS by reducing hepatic glucose output and adiposity. Using a transformed human subcutaneous preadipocyte cell line (Chub-S7) and human primary preadipocytes, we have defined the role of glucocorticoids and 11 beta-HSD1 in regulating adipose tissue differentiation. Human cells were differentiated with 1.0 mu M cortisol (F), or cortisone (E) with or without 100 nM of a highly selective 11 beta-HSD1 inhibitor PF-877423. 11 beta-HSD1 mRNA expression increased across adipocyte differentiation (P<0.001, n = 4), which was paralleled by an increase in 11 beta-HSD1 oxo-reductase activity (from nil on day 0 to 5.9 +/- 1.9 pmol/mg per h on day 16, P<0.01, n = 7). Cortisone enhanced adipocyte differentiation; fatty acid-binding protein 4 expression increased 312-fold (P<0.001) and glycerol-3-phosphate dehydrogenase 47-fold (P<0.001) versus controls. This was abolished by co-incubition with PF-877423. In addition, cellular lipid content decreased significantly. These findings were confirmed in the primary cultures of human Subcutaneous preadipocytes. The increase in 11 beta-HSD1 mRNA expression and activity is essential for the induction of human adipogenesis. Blocking adipogenesis with a novel and specific 11 beta-HSD1 inhibitor may represent a novel approach to treat obesity in patients with MS.Published here -
Gathercole LL, Bujalska IJ, Stewart PM, Tomlinson JW, 'Glucocorticoid modulation of insulin signaling in human subcutaneous adipose tissue'
The Journal of Clinical Endocrinology & Metabolism 92 (11) (2007) pp.4332-4339
ISSN: 0021-972XAbstractPublished hereContext: Glucocorticoid (GC) excess is characterized by central obesity, insulin resistance, and in some cases, type 2 diabetes. However, the impact of GC upon insulin signaling in human adipose tissue has not been fully explored.
Objective: We have examined the effect of GC upon insulin signaling in both human sc primary preadipocyte cultures and a novel human immortalized sc adipocyte cell line (Chub-S7) and contrasted this with observations in primary cultures of human skeletal muscle.
Design and Setting: This is an in vitro study characterizing the impact of GC upon insulin signaling in human tissues.
Patients: Biopsy specimens were from healthy volunteers who gave their full and informed written consent.
Interventions: Combinations of treatments, including GC, RU38486, and wortmannin, were used.
Main Outcome Measures: Insulin signaling cascade gene and protein expression and insulin-stimulated glucose uptake were determined.
Results: In human adipocytes, pretreatment with GC induced a dose-dependent [1.0 (control); 1.2 ± 0.1 (50 nm); 2.2 ± 0.2 (250 nm), P < 0.01 vs. control; 3.4 ± 0.2 (1000 nm), P < 0.001 vs. control] and time-dependent [1.0 (1 h); 3.2 ± 2.0 (6 h); 9.1 ± 5.9 (24 h), P < 0.05 vs. 1 h; 4.5 ± 2.2 (48 h)] increase in insulin-stimulated protein kinase B/akt phosphorylation. In addition, whereas insulin receptor substrate (IRS)-1 protein expression did not change, IRS-1 tyrosine phosphorylation increased. Furthermore, GC induced IRS-2 mRNA expression (2.8-fold; P < 0.05) and increased insulin-stimulated glucose uptake [1.0 (control) 1.8 ± 0.1 (insulin) vs. 2.8 ± 0.2 (insulin + GC); P < 0.05]. In contrast, in primary cultures of human muscle, GC decreased insulin-stimulated glucose uptake [1.0 (control) 1.9 ± 0.2 (insulin) vs. GC 1.3 ± 0.1 (insulin + GC); P < 0.05].
Conclusions: We have demonstrated tissue-specific regulation of insulin signaling by GC. Within sc adipose tissue, GCs augment insulin signaling, yet in muscle GCs cause insulin resistance. We propose that enhanced insulin action in adipose tissue increases adipocyte differentiation, thereby contributing to GC-induced obesity.
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Wattier RAM, Gathercole LL, Assinder SJ, Gliddon CJ, Deahl KL, Shaw DS, Mills DI, 'Sequence variation of intergenic mitochondrial DNA spacers (mtDNA-IGS) of Phytophthora infestans (Oomycetes) and related species'
Molecular Ecology Resources 3 (1) (2003) pp.136-138
ISSN: 1755-098X eISSN: 1755-0998AbstractThe potato late-blight disease is caused by the pseudofungus Phytophthora infestans (Oomycetes). This pathogen was of historical importance as it caused the Irish Potato Famine. There is currently a worldwide resurgence of the disease. Following worldwide migrations as well as being able to discriminate P. infestans from related species are key issues. We present sequence variation of five inter-genic mitochondrial DNA spacers (mtDNA-IGS) for P. infestans and four related taxa. Intra and inter-taxon variation was observed showing potential for both molecular ecology and molecular systematic.Published here
Book chapters
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Gathercole LL, Morgan SA, Tomlinson JW, 'Hormonal Regulation of Lipogenesis' in Litwack G (ed.), Hormonal Regulation of Lipogenesis, (2013)
ISSN: 0083-6729 ISBN: 978-0-12-407766-9AbstractPublished hereObesity has reached epidemic proportions with severe heath consequences including type 2 diabetes, nonalcoholic fatty liver disease, and premature cardiovascular mortality. Understanding the biological processes that govern fat deposition in a tissue-specific manner is therefore crucial if we are to try to design novel and efficacious treatments that might limit fat accumulation and improve metabolic phenotype and clinical prognosis.
Lipid accumulation within a given cell type represents a balance between synthesis, mobilization, and utilization. Common endocrine conditions characterized by hormonal excess and deficiency are often associated with profound abnormalities in body composition and fat deposition. This undoubtedly reflects the complex regulation of lipid metabolism by endocrine factors. In this review, we will outline the current literature that has investigated the hormonal regulation of lipogenesis. This is a complex field, and in many studies, its assessment has been oversimplified with a focus on individual hormones acting in isolation and this bears little relationship to the in vivo situation where multiple hormones act in concert. Further, regulation may be different between rodents and humans and this will be explored.
Limitation of lipid accumulation still represents a valid therapeutic target, and it is possible that manipulation of hormonal action has the potential to offer a new therapeutic horizon.
Other publications
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Shahmanesh M, Das S, Boothby M, Mcgee KC, Gathercole LL, Harte AL, Higgins P, Kusminski CM, McTernan PG, Ross J, Tomlinson JW, 'Complications of HIV Disease or Treatment', (2010)