Metformin Increases Cortisol Regeneration by 11βHSD1 in Obese Men With and Without Type 2 Diabetes Mellitus

Research into how carvacrol and metformin affect several human proteins in a hyperglycemic condition: A comparative study in silico and in vitro

Carvacrol (CV) is an organic compound found in the essential oils of many aromatic herbs. It is nearly unfeasible to analyze all the current human proteins for a query ligand using in vitro and in vivo methods. This study aimed to clarify whether CV possesses an anti-diabetic feature via Docking-based inverse docking and molecular dynamic (MD) simulation and in vitro characterization against a set of novel human protein targets. Herein, the best poses of CV docking simulations according to binding energy ranged from -7.9 to -3.5 (kcal/mol). After pathway analysis of the protein list through GeneMANIA and WebGestalt, eight interacting proteins (DPP4, FBP1, GCK, HSD11β1, INSR, PYGL, PPARA, and PPARG) with CV were determined, and these proteins exhibited stable structures during the MD process with CV. In vitro application, statistically significant results were achieved only in combined doses with CV or metformin. Considering all these findings, PPARG and INSR, among these target proteins of CV, are FDA-approved targets for treating diabetes. Therefore, CV may be on its way to becoming a promising therapeutic compound for treating Diabetes Mellitus (DM). Our outcomes expose formerly unexplored potential target human proteins, whose association with diabetic disorders might guide new potential treatments for DM.

Uncovering antiobesity-related hypertension targets and mechanisms of metformin, an antidiabetic medication

Metformin, a common clinical drug used to treat diabetes mellitus, is found with potential antiobese actions as reported in increasing evidences. However, the detailed mechanisms of metformin-antiobesity-related hypertension remain unrevealed. We have utilized the bioinformatics strategy, including network pharmacology and molecular docking analyses, to uncover pharmacological targets and molecular pathways of bioactive compounds against clinical disorders, such as cancers, coronavirus disease 2019. In this report, the in-silico approaches using network pharmacology and molecular docking was utilized to identify the core targets, pharmacological functions and mechanisms of metformin against obesity-related hypertension. The networking analysis identified 154 differentially expressed genes of obesity and hypertension, and 21 interaction genes, 6 core genes of metformin treating obesity-related hypertension. As results, molecular docking findings indicated the binding capability of metformin with key proteins, including interleukin 6 (IL-6) and chemokine (C-C motif) Ligand 2 (CCL2) expressed in obesity- and hypertension-dependent tissues. Metformin-exerted antihypertension/obesity actions involved in metabolic regulation, inflammatory suppression. And antihypertension/obesity mechanisms of metformin were revealed, including regulation of inflammatory and immunological signaling pathways for ameliorating microenvironmental homeostasis in targeting tissues. In conclusion, our current bioinformatics findings have uncovered all pharmacological targets, biological functions and signaling pathways of metformin treating obesity-related hypertension, thus promoting its clinical application in future.

Effects of Obesity and Insulin on Tissue-Specific Recycling Between Cortisol and Cortisone in Men

CONTEXT

11β-Hydroxysteroid dehydrogenase 1 (11βHSD1) reduces inert cortisone into active cortisol but also catalyzes reverse dehydrogenase activity. Drivers of cortisol/cortisone equilibrium are unclear. With obesity, 11βHSD1 transcripts are more abundant in adipose, but the consequences for oxidation vs reduction remain unknown.

OBJECTIVE

This work aimed to determine whether 11βHSD1 equilibrium in metabolic tissues is regulated by insulin and obesity.

METHODS

A 2-phase, randomized, crossover, single-blinded study in a clinical research facility was conducted of 10 lean and obese healthy men. 11β-Reductase and 11β-dehydrogenase activities were measured during infusion of 9,11,12,12-[2H]4-cortisol and 1,2-[2H]2-cortisone, respectively, on 2 occasions: once during saline infusion and once during a hyperinsulinemic-euglycemic clamp. Arterialized and venous samples were obtained across forearm skeletal muscle and abdominal subcutaneous adipose. Steroids were quantified by liquid chromatography-tandem mass spectrometry and adipose tissue transcripts by quantitative polymerase chain reaction.

RESULTS

Neither whole-body nor tissue-specific rates of production of cortisol or cortisone differed between lean and obese men, however insulin attenuated the diurnal decrease. Whole-body 11β-HSD1 reductase activity tended to be higher in obesity (~ 10%) and was further increased by insulin. Across adipose tissue, 11β-reductase activity was detected in obese individuals only and increased in the presence of insulin (18.99 ± 9.62 vs placebo 11.68 ± 3.63 pmol/100 g/minute; P < .05). Across skeletal muscle, 11β-dehydrogenase activity was reduced by insulin in lean men only (2.55 ± 0.90 vs 4.50 ± 1.42 pmol/100 g/minute, P < .05).

CONCLUSIONS

Regeneration of cortisol is upregulated by insulin in adipose tissue but not skeletal muscle. In obesity, the equilibrium between 11β-reductase and 11β-dehydrogenase activities likely promotes cortisol accumulation in adipose, which may lead to adverse metabolic consequences.

Inhibitors of 11β-Hydroxysteroid Dehydrogenase Type 1 as Potential Drugs for Type 2 Diabetes Mellitus—A Systematic Review of Clinical and In Vivo Preclinical Studies

Diabetes mellitus is a pathology with increasing frequency in society, being one of the main causes of death worldwide. For this reason, new therapeutic targets have been studied over the years. 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is an enzyme responsible for reducing cortisone to its active form cortisol, which can lead to metabolic changes such as insulin resistance and hyperglycemia. Therefore, 11β-HSD1 inhibition may offer a new therapeutic approach for type 2 diabetes mellitus. This work intends to systematically review the available scientific evidence on this subject. For this, a search was conducted in three databases and 15 clinical and in vivo preclinical studies were included in this review. Despite the high inhibitory and selectivity levels achieved with several molecules and the demonstrated clinical efficacy in diabetes treatment, no phase III clinical trials have yet been conducted. This is important because the long-term effects of 11β-HSD1 inhibitors including the consequences in hypothalamic–pituitary–adrenal axis must be evaluated. However, this enzyme remains a promising target for drug development, including due to its effectiveness in controlling various factors that constitute the metabolic syndrome and its potential for multiple indications in patients with diabetes, including wound healing and weight loss.

Diet-induced weight loss alters hepatic glucocorticoid metabolism in type 2 diabetes mellitus

CONTEXT

Altered tissue-specific glucocorticoid metabolism has been described in uncomplicated obesity and type 2 diabetes. We hypothesized that weight loss induced by diet and exercise, which has previously been shown to reverse abnormal cortisol metabolism in uncomplicated obesity, also normalizes cortisol metabolism in patients with type 2 diabetes.

OBJECTIVE

Test the effects of a diet intervention with added exercise on glucocorticoid metabolism.

DESIGN

Two groups followed a Paleolithic diet (PD) for 12 weeks with added 180 min of structured aerobic and resistance exercise per week in one randomized group (PDEX).

SETTING

Umeå University Hospital.

PARTICIPANTS

Men and women with type 2 diabetes treated with lifestyle modification ± metformin were included. Twenty-eight participants (PD, n = 15; PDEX, n = 13) completed measurements of glucocorticoid metabolism.

MAIN OUTCOME MEASURES

Changes in glucocorticoid metabolite levels in 24-h urine samples, expression of HSD11B1 mRNA in s.c. adipose tissue and conversion of orally administered cortisone to cortisol measured in plasma. Body composition and insulin sensitivity were measured using a hyperinsulinemic-euglycemic clamp, and liver fat was measured by magnetic resonance spectroscopy.

RESULTS

Both groups lost weight and improved insulin sensitivity. Conversion of orally taken cortisone to plasma cortisol and the ratio of 5α-THF + 5β-THF/THE in urine increased in both groups.

CONCLUSIONS

These interventions caused weight loss and improved insulin sensitivity with concomitant increases in the conversion of cortisone to cortisol, which is an estimate of hepatic HSD11B1 activity. This suggests that dysregulation of liver glucocorticoid metabolism in these patients is a consequence rather than a cause of metabolic dysfunction.

Metformin to reduce metabolic complications and inflammation in patients on systemic glucocorticoid therapy: a randomised, double-blind, placebo-controlled, proof-of-concept, phase 2 trial

BACKGROUND

An urgent need to reduce the metabolic side-effects of glucocorticoid overexposure has been recognised, as glucocorticoid excess can lead to Cushing's syndrome, which is associated with high morbidity. We aimed to evaluate the potential of metformin to reverse such effects while sparing the anti-inflammatory benefits of glucocorticoids.

METHODS

We did a randomised, double-blind, placebo-controlled, proof-of-concept, phase 2 trial involving four hospitals in the UK. Patients without diabetes were eligible if they were between the ages of 18 and 75 years with an inflammatory disease treated with continuous prednisolone (≥20 mg/day for ≥4 weeks and remaining on ≥10 mg/day for the subsequent 12 weeks, or its cumulative dose-equivalent). Eligible patients were randomly allocated (1:1) to either the metformin or placebo groups, using a computer-generated randomisation table stratified according to age and BMI. Metformin and placebo were administered orally for 12 weeks in escalating doses: 850 mg/day for the first 5 days, 850 mg twice a day for the next 5 days, and 850 mg three times a day subsequently. The primary outcome was the between-group difference in visceral-to-subcutaneous fat area ratio over 12 weeks, assessed by CT. Secondary outcomes included changes in metabolic, bone, cardiovascular, and inflammatory parameters over 12 weeks. Our analysis followed a modified intention-to-treat principle for the primary outcome. This study is registered with ClinicalTrials.gov, NCT01319994.

FINDINGS

Between July 17, 2012, and Jan 14, 2014, 849 patients were assessed for study eligibility, of which 53 were randomly assigned to receive either metformin (n=26) or placebo (n=27) for 12 weeks. 19 patients in the metformin group and 21 in the placebo group were eligible for the primary outcome analysis. Both groups received an equivalent cumulative dose of glucocorticoids (1860 mg prednisolone-equivalent [IQR 1060-2810] in the metformin group vs 1770 mg [1020-2356] in the placebo group); p=0·76). No change in the visceral-to-subcutaneous fat area ratio between the treatment groups was observed (0·11, 95% CI -0·02 to 0·24; p=0·09), but patients in the metformin group lost truncal subcutaneous fat compared with the placebo group (-3835 mm², 95% CI -6781 to -888; p=0·01). Improvements in markers of carbohydrate, lipid, liver, and bone metabolism were observed in the metformin group compared with the placebo group. Additionally, those in the metformin group had improved fibrinolysis, carotid intima-media thickness, inflammatory parameters, and clinical markers of disease activity. The frequency of pneumonia (one event in the metformin group vs seven in the placebo group; p=0·01), overall rate of moderate-to-severe infections (two vs 11; p=0·001), and all-cause hospital admissions due to adverse events (one vs nine; p=0·001) were lower in the metformin group than in the placebo group. Patients in the metformin group had more events of diarrhoea than the placebo group (18 events vs eight; p=0·01).

INTERPRETATION

No significant changes in the visceral-to-subcutaneous fat area ratio between the treatment groups were observed; however, metformin administration did improve some of the metabolic profile and clinical outcomes for glucocorticoid-treated patients with inflammatory disease, which warrants further investigation.

FUNDING

Barts Charity and Merck Serono.

Individual differences in glucocorticoid regulation: Does it relate to disease risk and resilience?

Glucocorticoid (GC) signaling varies among individuals, and this variation may relate to individual differences in health outcomes. To determine if and which aspects of signaling (basal, circadian, integrative, or reactivity) are associated with specific health outcomes, we reviewed recent studies that relate GCs to health outcomes. We identified papers through PubMed and reviewed 100 original research articles related to mental health, cardiovascular health, cancer, diabetes, obesity, pulmonary health, sleep, and fitness. Many studies reported elevated GC secretion associated with worse health, but this was only particularly true for integrative GC measures. On the other hand, accentuated cortisol awakening response and a steeper circadian rhythm were both associated with positive health outcomes. Overall, relationships between GC secretion and health outcomes were relatively weak. This systematic review of relationships between GC metrics and health outcomes highlights the importance of careful consideration when selecting methods to measure GC regulation in health research.

Lower Renal Function Is Associated With Derangement of 11-β Hydroxysteroid Dehydrogenase in Type 2 Diabetes

Context

Derangement of 11-β hydroxysteroid dehydrogenase type 1 and type 2 (11β-HSD1 and 11β-HSD2), which regulate intracellular cortisol production, has been suggested in both type 2 diabetes (T2D) and chronic kidney disease (CKD). However, activity of 11β-HSD enzymes in patients with T2D and CKD has never been assessed.

Objectives

To compare 11β-HSD activities between patients with T2D and healthy controls, and assess whether in T2D, renal function is associated with 11β-HSD activities.

Design

Cross-sectional analysis in the Diabetes and Lifestyle Cohort Twente (DIALECT-1).

Setting

Referral center for T2D.

Patients

Patient with T2D [n = 373, age 64 ± 9 years, 58% men, 26% of patients estimated glomerular filtration rate (eGFR) <60 mL/min·1.73 m²] and healthy controls (n = 275, age 53 ± 11 years, 48% men).

Mean Outcome Measure

We measured cortisol, cortisone, and metabolites [tetrahydrocortisol (THF), allo-THF (aTHF), and tetrahydrocortisone (THE)] in 24-hour urine samples. Whole body 11β-HSD and 11β-HSD2 activities were calculated as the urinary (THF + aTHF)/THE and cortisol/cortisone ratios, respectively.

Results

Patients with T2D had a higher (THF + aTHF)/THE ratio [1.02 (0.84 to 1.27) vs 0.94 (0.79 to 1.0), P < 0.001] and cortisol/cortisone ratio [0.70 (0.58 to 0.83) vs 0.63 (0.54 to 0.74), P < 0.001] than healthy controls. In T2D, lower eGFR was associated with a higher (THF + aTHF)/THE ratio (β = −0.35, P < 0.001), and a higher cortisol/cortisone ratio (β = −0.16, P = 0.001).

Conclusions

In this real-life secondary care setting of patients with T2D, 11β-HSD enzymes activities were shifted to higher intracellular cortisol production in T2D, which was further aggravated in patients with CKD. Prospective analyses are warranted to investigate causality of these associations.

Neonatal overfeeding induced glucocorticoid overexposure accelerates hepatic lipogenesis in male rats

Background

Postnatal overfeeding activates tissue glucocorticoid (GC) activity by up-regulating 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) and increasing sensitivity to high-fat (HF) diet-induced non-alcoholic fatty liver disease (NAFLD). The present study aimed to evaluate the effects of postnatal overfeeding on GC regulation and lipogenesis in the liver and to observe the impact of GC on hepatocyte lipid metabolism.

Methods

In vivo, Male Sprague-Dawley rat pup litters were adjusted to litter sizes of three (small litter, SL) or ten (normal litter, NL) on postnatal day 3 and then given standard chow from postnatal week 3 (W3) to W13. In vitro, HepG2 cells were stimulated by GC, mifepristone (Mi) or GC + Mi within 48 h, followed by sodium oleate (OA) intervention (or not) for 24 h. Intracellular lipid droplets, triglyceride (TG) concentrations and gene expression related to lipid metabolism were measured in hepatic tissues or HepG2 cells.

Results

In vivo, weight gain in the body and liver and TG concentrations in the liver were significantly increased in the SL rats compared to the NL rats at W3 and W13 (p < 0.05); mRNA expression of hepatic 11β-HSD1, acetyl-CoA carboxylase 1 (ACC), stearoyl-CoA desaturase-1 (SCD1), fatty acid synthase (FASN) and their nuclear transcription factor, sterol regulatory element binding protein-1c (SREBP-1c) (p < 0.05), was also increased. In vitro, intracellular lipid droplets and TG content in HepG2 cells increased under stimulation with GC or OA (p < 0.05); the increase was more significant following treatment with GC and OA together (p < 0.05). The ACC, SCD1, FASN and SREBP-1c mRNA expression changes were highly similar to the changes in TG content in cells. All the changes induced by GC disappeared when the glucocorticoid receptor (GR) was blocked by Mi.

Conclusions

Postnatal overfeeding induced GC overexposure through 11β-HSD1 up-regulation in the liver. GC activated hepatic de novo lipogenesis (DNL) via GR and led to hepatic lipid accumulation, which increased the risk of NAFLD during adulthood.

Quantification of 11β-hydroxysteroid dehydrogenase 1 kinetics and pharmacodynamic effects of inhibitors in brain using mass spectrometry imaging and stable-isotope tracers in mice

11β-Hydroxysteroid dehydrogenase 1 (11β-HSD1; EC 1.1.1.146) generates active glucocorticoid hormones. Small molecule inhibitors have been developed to target 11β-HSD1 for the treatment of dementia; these must enter brain subregions, such as the hippocampus, to be effective. We previously reported mass spectrometry imaging measurement of murine tissue steroids, and deuterated steroid tracer infusion quantification of 11β-HSD1 turnover in humans. Here, these tools are combined to assess tissue pharmacokinetics and pharmacodynamics of an 11β-HSD1 inhibitor that accesses the brain.

[9,11,12,12-²H]₄-Cortisol was infused (1.75 mg/day) by minipump for 2 days into C57Bl6 mice (male, age 12 weeks, n = 3/group) after which an 11β-HSD1 inhibitor (UE2316) was administered (25 mg/kg oral gavage) and animals culled immediately or 1, 2 and 4 h post-dosing. Mice with global genetic disruption of Hsd11B1 were studied similarly. Turnover of d4-cortisol to d3-cortisone (by loss of the 11-deuterium) and regeneration of d3-cortisol (by 11β-HSD1-mediated reduction) were assessed in plasma, liver and brain using matrix assisted laser desorption ionization coupled to Fourier transform cyclotron resonance mass spectrometry.

The tracer d4-cortisol was detected in liver and brain following a two day infusion. Turnover to d3-cortisone and on to d3-cortisol was slower in brain than liver. In contrast, d3-cortisol was not detected in mice lacking 11β-HSD1. UE2316 impaired d3-cortisol generation measured in whole body (assessed in plasma; 53.1% suppression in rate of appearance in d3-cortisol), liver and brain. Differential inhibition in brain regions was observed; active glucocorticoids were suppressed to a greater in extent hippocampus or cortex than in amygdala.

These data confirm that the contribution of 11β-HSD1 to the tissue glucocorticoid pool, and the consequences of enzyme inhibition on active glucocorticoid concentrations, are substantial, including in the brain. They further demonstrate the value of mass spectrometry imaging in pharmacokinetic and pharmacodynamic studies.

11β-HSD2 SUMOylation Modulates Cortisol-Induced Mineralocorticoid Receptor Nuclear Translocation Independently of Effects on Transactivation

The enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) has an essential role in aldosterone target tissues, conferring aldosterone selectivity for the mineralocorticoid receptor (MR) by converting 11β-hydroxyglucocorticoids to inactive 11-ketosteroids. Congenital deficiency of 11β-HSD2 causes a form of salt-sensitive hypertension known as the syndrome of apparent mineralocorticoid excess. The disease phenotype, which ranges from mild to severe, correlates well with reduction in enzyme activity. Furthermore, polymorphisms in the 11β-HSD2 coding gene (HSD11B2) have been linked to high blood pressure and salt sensitivity, major cardiovascular risk factors. 11β-HSD2 expression is controlled by different factors such as cytokines, sex steroids, or vasopressin, but posttranslational modulation of its activity has not been explored. Analysis of 11β-HSD2 sequence revealed a consensus site for conjugation of small ubiquitin-related modifier (SUMO) peptide, a major posttranslational regulatory event in several cellular processes. Our results demonstrate that 11β-HSD2 is SUMOylated at lysine 266. Non-SUMOylatable mutant K266R showed slightly higher substrate affinity and decreased Vmax, but no effects on protein stability or subcellular localization. Despite mild changes in enzyme activity, mutant K266R was unable to prevent cortisol-dependent MR nuclear translocation. The same effect was achieved by coexpression of wild-type 11β-HSD2 with sentrin-specific protease 1, a protease that catalyzes SUMO deconjugation. In the presence of 11β-HSD2-K266R, increased nuclear MR localization did not correlate with increased response to cortisol or increased recruitment of transcriptional coregulators. Taken together, our data suggests that SUMOylation of 11β-HSD2 at residue K266 modulates cortisol-mediated MR nuclear translocation independently of effects on transactivation.