Tissue Glucocorticoid Metabolism in Adrenal Insufficiency: A Prospective Study of Dual-release Hydrocortisone Therapy.

BACKGROUND: Patients with adrenal insufficiency (AI) require life-long glucocorticoid (GC) replacement therapy. Within tissues, cortisol (F) availability is under the control of the isozymes of 11ß-hydroxysteroid dehydrogenase (11ß-HSD). We hypothesize that corticosteroid metabolism is altered in patients with AI because of the nonphysiological pattern of current immediate release hydrocortisone (IR-HC) replacement therapy. The use of a once-daily dual-release hydrocortisone (DR-HC) preparation, (Plenadren®), offers a more physiological cortisol profile and may alter corticosteroid metabolism in vivo. STUDY DESIGN AND METHODS: Prospective crossover study assessing the impact of 12 weeks of DR-HC on systemic GC metabolism (urinary steroid metabolome profiling), cortisol activation in the liver (cortisone acetate challenge test), and subcutaneous adipose tissue (microdialysis, biopsy for gene expression analysis) in 51 patients with AI (primary and secondary) in comparison to IR-HC treatment and age- and BMI-matched controls. RESULTS: Patients with AI receiving IR-HC had a higher median 24-hour urinary excretion of cortisol compared with healthy controls (72.1 µg/24 hours [IQR 43.6-124.2] vs 51.9 µg/24 hours [35.5-72.3], P = .02), with lower global activity of 11ß-HSD2 and higher 5-alpha reductase activity. Following the switch from IR-HC to DR-HC therapy, there was a significant reduction in urinary cortisol and total GC metabolite excretion, which was most significant in the evening. There was an increase in 11ß-HSD2 activity. Hepatic 11ß-HSD1 activity was not significantly altered after switching to DR-HC, but there was a significant reduction in the expression and activity of 11ß-HSD1 in subcutaneous adipose tissue. CONCLUSION: Using comprehensive in vivo techniques, we have demonstrated abnormalities in corticosteroid metabolism in patients with primary and secondary AI receiving IR-HC. This dysregulation of pre-receptor glucocorticoid metabolism results in enhanced glucocorticoid activation in adipose tissue, which was ameliorated by treatment with DR-HC.

Nuclear Magnetic Resonance Spectroscopy Metabolomics in Idiopathic Intracranial Hypertension to Identify Markers of Disease and Headache.

BACKGROUND AND OBJECTIVE: We evaluated the metabolomic profile in CSF, serum and urine of participants with idiopathic intracranial hypertension (IIH) compared to controls and measured changes in metabolism associated with clinical markers of disease activity and treatment. METHODS: A case-control study compared women aged 18-55 years with active IIH (Friedman diagnostic criteria), to a sex, age and body mass index matched control group. IIH participants were identified from neurology and ophthalmology clinics from National Health Service hospitals and underwent a prospective intervention to induce disease remission through weight loss with re-evaluation at 12 months. Clinical assessments included lumbar puncture, headache, papilledema and visual measurements. Spectra of CSF, serum and urine metabolites were acquired utilizing proton nuclear magnetic resonance spectroscopy. RESULTS: Urea was lower in IIH (CSF; controls median ±IQR 0.196 ±0.008, IIH 0.058 ±0.059, p<0.001, urine; controls 5971.370 ±3021.831, IIH 4691.363 ±1955.774, p=0.009), correlated with ICP (urine p=0.019) and headache severity (CSF p=0.031) and increased by 12 months (CSF 12 months; 0.175 ±0.043, p=0.004, urine; 5210.874 ±1825.302, p=0.043). The lactate:pyruvate ratio was increased compared to controls (CSF; controls 49.739 ±19.523, IIH 113.114 ±117.298, p=0.023, serum; controls 38.187 ±13.392, IIH 54.547 ±18.471, p=0.004) and decreased at 12 months (CSF; 113.114 ±117.298, p<0.001). Baseline acetate was higher in IIH (CSF; controls 0.128 ±0.041, IIH 0.192 ±0.151, p=0.008), correlated with headache severity (p = 0.030) and headache disability (p = 0.003) and was reduced at 12 months (0.160 ±0.060, p = 0.007). Ketones 3-hydroxybutyrate and acetoacetate were altered in CSF at baseline in IIH (3-hydroxybutyrate; controls 0.074 ±0.063, IIH 0.049 ±0.055, p = 0.019, acetoacetate; controls 0.013 ±0.007, IIH 0.017 ±0.010, p = 0.013) and normalized at 12 months (0.112 ±0.114, p = 0.019, 0.029 ±0.017, p = 0.015 respectively). DISCUSSION: We observed metabolic disturbances that are evident in CSF, serum and urine of IIH participants, suggesting global metabolic dysregulation. Altered ketone body metabolites normalized following therapeutic weight loss. CSF:serum urea ratio was altered which may influence ICP dynamics and headache. Elevated CSF acetate, known to stimulate trigeminal sensitization, was associated with headache morbidity. These alterations of metabolic pathways specific to IIH provide biological insight and warrants mechanistic evaluation.

Increased systemic and adipose 11ß-HSD1 activity in idiopathic intracranial hypertension.

Context: Idiopathic intracranial hypertension (IIH) is a disease of raised intracranial pressure (ICP) of unknown etiology. Reductions in glucocorticoid metabolism are associated with improvements in IIH disease activity. The basal IIH glucocorticoid metabolism is yet to be assessed. Objective: The objective of this study was to determine the basal glucocorticoid phenotype in IIH and assess the effects of weight loss on the IIH glucocorticoid phenotype. Design: A retrospective case-control study and a separate exploratory analysis of a prospective randomized intervention study were carried out. Methods: The case-control study compared female IIH patients to BMI, age, and sex-matched controls. In the randomized intervention study, different IIH patients were randomized to either a community weight management intervention or bariatric surgery, with patients assessed at baseline and 12 months. Glucocorticoid levels were determined utilizing 24-h urinary steroid profiles alongside the measurement of adipose tissue 11ß-HSD1 activity. Results: Compared to control subjects, patients with active IIH had increased systemic 11ß-hydroxysteroid dehydrogenase (11ß-HSD1) and 5α-reductase activity. The intervention study demonstrated that weight loss following bariatric surgery reduced systemic 11ß-HSD1 and 5α-reductase activity. Reductions in these were associated with reduced ICP. Subcutaneous adipose tissue explants demonstrated elevated 11ß-HSD1 activity compared to samples from matched controls. Conclusion: The study demonstrates that in IIH, there is a phenotype of elevated systemic and adipose 11ß-HSD1 activity in excess to that mediated by obesity. Bariatric surgery to induce weight loss was associated with reductions in 11ß-HSD1 activity and decreased ICP. These data reflect new insights into the IIH phenotype and further point toward metabolic dysregulation as a feature of IIH.

Proline synthesis through PYCR1 is required to support cancer cell proliferation and survival in oxygen-limiting conditions.

The demands of cancer cell proliferation alongside an inadequate angiogenic response lead to insufficient oxygen availability in the tumor microenvironment. Within the mitochondria, oxygen is the major electron acceptor for NADH, with the result that the reducing potential produced through tricarboxylic acid (TCA) cycle activity and mitochondrial respiration are functionally linked. As the oxidizing activity of the TCA cycle is required for efficient synthesis of anabolic precursors, tumoral hypoxia could lead to a cessation of proliferation without another means of correcting the redox imbalance. We show that in hypoxic conditions, mitochondrial pyrroline 5-carboxylate reductase 1 (PYCR1) activity is increased, oxidizing NADH with the synthesis of proline as a by-product. We further show that PYCR1 activity is required for the successful maintenance of hypoxic regions by permitting continued TCA cycle activity, and that its loss leads to significantly increased hypoxia in vivo and in 3D culture, resulting in widespread cell death.

Obstructive sleep apnoea in women with idiopathic intracranial hypertension: a sub-study of the idiopathic intracranial hypertension weight randomised controlled trial (IIH: WT).

OBJECTIVE: Obesity is a risk factor for idiopathic intracranial hypertension (IIH) and obstructive sleep apnoea (OSA). We aimed to determine the prevalence of OSA in IIH and evaluate the diagnostic performance of OSA screening tools in IIH. Additionally, we evaluated the relationship between weight loss, OSA and IIH over 12 months. METHODS: A sub-study of a multi-centre, randomised controlled parallel group trial comparing the impact of bariatric surgery vs. community weight management intervention (CWI) on IIH-related outcomes over 12 months (IIH:WT). OSA was assessed using home-based polygraphy (ApneaLink Air, ResMed) at baseline and 12 months. OSA was defined as an apnoea-hypopnoea index (AHI) ≥ 15 or ≥ 5 with excessive daytime sleepiness (Epworth Sleepiness Scale ≥11 ). RESULTS: Of the 66 women in the IIH: WT trial, 46 were included in the OSA sub-study. OSA prevalence was 47% (n = 19). The STOP-BANG had the highest sensitivity (84%) compared to the Epworth Sleepiness Scale (69%) and Berlin (68%) to detect OSA. Bariatric surgery resulted in greater reductions in AHI vs. CWI (median [95%CI] AHI reduction of - 2.8 [ - 11.9, 0.7], p = 0.017). Over 12 months there was a positive association between changes in papilloedema and AHI (r = 0.543, p = 0.045), despite adjustment for changes in the body mass index (R2 = 0.522, p = 0.017). CONCLUSION: OSA is common in IIH and the STOP-BANG questionnaire was the most sensitive screening tool. Bariatric surgery improved OSA in patients with IIH. The improvement in AHI was associated with improvement in papilloedema independent of weight loss. Whether OSA treatment has beneficial impact on papilloedema warrants further evaluation. TRIAL REGISTRATION NUMBER: IIH: WT is registered as ISRCTN40152829 and on ClinicalTrials.gov as NCT02124486 (28/04/2014).

Evaluation of the mechanisms of sarcopenia in chronic inflammatory disease: protocol for a prospective cohort study.

BACKGROUND: Several chronic inflammatory diseases co-exist with and accelerate sarcopenia (reduction in muscle strength, function and mass) and negatively impact on both morbidity and mortality. There is currently limited research on the extent of sarcopenia in such conditions, how to accurately assess it and whether there are generic or disease-specific mechanisms driving sarcopenia. Therefore, this study aims to identify potential mechanisms driving sarcopenia within chronic inflammatory disease via a multi-modal approach; in an attempt to help define potential interventions for future use. METHODS: This prospective cohort study will consist of a multi-modal assessment of sarcopenia and its underlying mechanisms. Recruitment will target three chronic inflammatory diseases: chronic liver disease (CLD) (n=50), with a subset of NAFLD (n=20), inflammatory bowel disease (IBD) (n=50) and rheumatoid arthritis (RA) (n=50) both before and after therapeutic intervention. In addition, 20 age and sex matched healthy individuals will be recruited for comparison. Participants will undergo 4 assessment visits at weeks 0, 2, 12 and 24. Visits will consist of the following assessments: blood tests, anthropometrics, functional assessment, quadriceps muscle imaging, actigraphy, quality of life questionnaires, food diary collection and muscle biopsy of the vastus lateralis (at weeks 2 and 24 only). In addition, stool and urine samples will be collected for future microbiome and metabolomics analysis. DISCUSSION: This is the first study to use a multi-modal assessment model to phenotype sarcopenia in these chronic inflammatory diseases. We hope to identify generic as well as disease-specific mechanisms driving sarcopenia. We appreciate that these cohorts do require separate standards of care treatments which limit comparison between groups. ETHICS AND DISSEMINATION: The study is approved by the Health Research Authority - West Midlands Solihull Research Ethics Service Committee Authority (REC reference: 18/WM/0167). Recruitment commenced in January 2019 and will continue until July 2021. The study was halted in March 2020 and again in January 2021 with the COVID-19 pandemic. The findings will be disseminated through peer-reviewed publications and conference presentations. All data will be stored on a secure server. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04734496.

Cognitive performance in idiopathic intracranial hypertension and relevance of intracranial pressure.

Cognitive impairments have been reported in idiopathic intracranial hypertension; however, evidence supporting these deficits is scarce and contributing factors have not been defined. Using a case-control prospective study, we identified multiple domains of deficiency in a cohort of 66 female adult idiopathic intracranial hypertension patients. We identified significantly impaired attention networks (executive function) and sustained attention compared to a body mass index and age matched control group of 25 healthy female participants. We aimed to investigate how cognitive function changed over time and demonstrated that deficits were not permanent. Participants exhibited improvement in several domains including executive function, sustained attention and verbal short-term memory over 12-month follow-up. Improved cognition over time was associated with reduction in intracranial pressure but not body weight. We then evaluated cognition before and after a lumbar puncture with acute reduction in intracranial pressure and noted significant improvement in sustained attention to response task performance. The impact of comorbidities (headache, depression, adiposity and obstructive sleep apnoea) was also explored. We observed that body mass index and the obesity associated cytokine interleukin-6 (serum and cerebrospinal fluid) were not associated with cognitive performance. Headache severity during cognitive testing, co-morbid depression and markers of obstructive sleep apnoea were adversely associated with cognitive performance. Dysregulation of the cortisol generating enzyme 11ß hydroxysteroid dehydrogenase type 1 has been observed in idiopathic intracranial hypertension. Elevated cortisol has been associated with impaired cognition. Here, we utilized liquid chromatography-tandem mass spectrometry for multi-steroid profiling in serum and cerebrospinal fluid in idiopathic intracranial hypertension patients. We noted that reduction in the serum cortisol:cortisone ratio in those undergoing bariatric surgery at 12 months was associated with improving verbal working memory. The clinical relevance of cognitive deficits was noted in their significant association with impaired reliability to perform visual field tests, the cornerstone of monitoring vision in idiopathic intracranial hypertension. Our findings propose that cognitive impairment should be accepted as a clinical manifestation of idiopathic intracranial hypertension and impairs the ability to perform visual field testing reliably. Importantly, cognitive deficits can improve over time and with reduction of intracranial pressure. Treating comorbid depression, obstructive sleep apnoea and headache could improve cognitive performance in idiopathic intracranial hypertension.

Prolyl-4-hydroxylase 3 maintains ß cell glucose metabolism during fatty acid excess in mice.

The α-ketoglutarate-dependent dioxygenase, prolyl-4-hydroxylase 3 (PHD3), is an HIF target that uses molecular oxygen to hydroxylate peptidyl prolyl residues. Although PHD3 has been reported to influence cancer cell metabolism and liver insulin sensitivity, relatively little is known about the effects of this highly conserved enzyme in insulin-secreting ß cells in vivo. Here, we show that the deletion of PHD3 specifically in ß cells (ßPHD3KO) was associated with impaired glucose homeostasis in mice fed a high-fat diet. In the early stages of dietary fat excess, ßPHD3KO islets energetically rewired, leading to defects in the management of pyruvate fate and a shift from glycolysis to increased fatty acid oxidation (FAO). However, under more prolonged metabolic stress, this switch to preferential FAO in ßPHD3KO islets was associated with impaired glucose-stimulated ATP/ADP rises, Ca2+ fluxes, and insulin secretion. Thus, PHD3 might be a pivotal component of the ß cell glucose metabolism machinery in mice by suppressing the use of fatty acids as a primary fuel source during the early phases of metabolic stress.

Systemic and adipocyte transcriptional and metabolic dysregulation in idiopathic intracranial hypertension.

BACKGROUNDIdiopathic intracranial hypertension (IIH) is a condition predominantly affecting obese women of reproductive age. Recent evidence suggests that IIH is a disease of metabolic dysregulation, androgen excess, and an increased risk of cardiovascular morbidity. Here we evaluate systemic and adipose specific metabolic determinants of the IIH phenotype.METHODSIn fasted, matched IIH (n = 97) and control (n = 43) patients, we assessed glucose and insulin homeostasis and leptin levels. Body composition was assessed along with an interrogation of adipose tissue function via nuclear magnetic resonance metabolomics and RNA sequencing in paired omental and subcutaneous biopsies in a case-control study.RESULTSWe demonstrate an insulin- and leptin-resistant phenotype in IIH in excess of that driven by obesity. Adiposity in IIH is preferentially centripetal and is associated with increased disease activity and insulin resistance. IIH adipocytes appear transcriptionally and metabolically primed toward depot-specific lipogenesis.CONCLUSIONThese data show that IIH is a metabolic disorder in which adipose tissue dysfunction is a feature of the disease. Managing IIH as a metabolic disease could reduce disease morbidity and improve cardiovascular outcomes.FUNDINGThis study was supported by the UK NIHR (NIHR-CS-011-028), the UK Medical Research Council (MR/K015184/1), Diabetes UK, Wellcome Trust (104612/Z/14/Z), the Sir Jules Thorn Award, and the Midlands Neuroscience Teaching and Research Fund.

The effect of young and old ex vivo human serum on cellular protein synthesis and growth in an in vitro model of aging.

In vitro models of muscle aging are useful for understanding mechanisms of age-related muscle loss and aiding the development of targeted therapies. To investigate mechanisms of age-related muscle loss in vitro utilizing ex vivo human serum, fasted blood samples were obtained from four old (72 ± 1 yr) and four young (26 ± 3 yr) men. Older individuals had elevated levels of plasma CRP, IL-6, HOMA-IR, and lower concentric peak torque and work-per-repetition compared with young participants (P < 0.05). C2C12 myotubes were serum and amino acid starved for 1 h and conditioned with human serum (10%) for 4 h or 24 h. After 4 h, C2C12 cells were treated with 5 mM leucine for 30 min. Muscle protein synthesis (MPS) was determined through the surface sensing of translation (SUnSET) technique and regulatory signaling pathways were measured via Western blot. Myotube diameter was significantly reduced in myotubes treated with serum from old, in comparison to young donors (84%, P < 0.001). MPS was reduced in myotubes treated with old donor serum, compared with young serum before leucine treatment (32%, P < 0.01). MPS and the phosphorylation of Akt, p70S6K, and eEF2 were increased in myotubes treated with young serum in response to leucine treatment, with a blunted response identified in cells treated with old serum (P < 0.05). Muscle protein breakdown signaling pathways did not differ between groups. In summary, we show that myotubes conditioned with serum from older individuals had decreased myotube diameter and MPS compared with younger individuals, potentially driven by low-grade systemic inflammation.

Effectiveness of Bariatric Surgery vs Community Weight Management Intervention for the Treatment of Idiopathic Intracranial Hypertension: A Randomized Clinical Trial.

Importance: Idiopathic intracranial hypertension (IIH) causes headaches, vision loss, and reduced quality of life. Sustained weight loss among patients with IIH is necessary to modify the disease and prevent relapse. Objective: To compare the effectiveness of bariatric surgery with that of a community weight management (CWM) intervention for the treatment of patients with active IIH. Design, Setting, and Participants: This 5-year randomized clinical trial (Idiopathic Intracranial Hypertension Weight Trial) enrolled women with active IIH and a body mass index (calculated as weight in kilograms divided by height in meters squared) of 35 or higher at 5 National Health Service hospitals in the UK between March 1, 2014, and May 25, 2017. Of 74 women assessed for eligibility, 6 did not meet study criteria and 2 declined to participate; 66 women were randomized. Data were analyzed from November 1, 2018, to May 14, 2020. Interventions: Bariatric surgery (n = 33) or CWM intervention (Weight Watchers) (n = 33). Main Outcomes and Measures: The primary outcome was change in intracranial pressure measured by lumbar puncture opening pressure at 12 months, as assessed in an intention-to-treat analysis. Secondary outcomes included lumbar puncture opening pressure at 24 months as well as visual acuity, contrast sensitivity, perimetric mean deviation, and quality of life (measured by the 36-item Short Form Health Survey) at 12 and 24 months. Because the difference in continuous outcomes between groups is presented, the null effect was at 0. Results: Of the 66 female participants (mean [SD] age, 32.0 [7.8] years), 64 (97.0%) remained in the clinical trial at 12 months and 54 women (81.8%) were included in the primary outcome analysis. Intracranial pressure was significantly lower in the bariatric surgery arm at 12 months (adjusted mean [SE] difference, -6.0 [1.8] cm cerebrospinal fluid [CSF]; 95% CI, -9.5 to -2.4 cm CSF; P = .001) and at 24 months (adjusted mean [SE] difference, -8.2 [2.0] cm CSF; 95% CI, -12.2 to -4.2 cm CSF; P < .001) compared with the CWM arm. In the per protocol analysis, intracranial pressure was significantly lower in the bariatric surgery arm at 12 months (adjusted mean [SE] difference, -7.2 [1.8] cm CSF; 95% CI, -10.6 to -3.7 cm CSF; P < .001) and at 24 months (adjusted mean [SE] difference, -8.7 [2.0] cm CSF; 95% CI, -12.7 to -4.8 cm CSF; P < .001). Weight was significantly lower in the bariatric surgery arm at 12 months (adjusted mean [SE] difference, -21.4 [5.4] kg; 95% CI, -32.1 to -10.7 kg; P < .001) and at 24 months (adjusted mean [SE] difference, -26.6 [5.6] kg; 95% CI, -37.5 to -15.7 kg; P < .001). Quality of life was significantly improved at 12 months (adjusted mean [SE] difference, 7.3 [3.6]; 95% CI, 0.2-14.4; P = .04) and 24 months (adjusted mean [SE] difference, 10.4 [3.8]; 95% CI, 3.0-17.9; P = .006) in the bariatric surgery arm. Conclusions and Relevance: In this randomized clinical trial, bariatric surgery was superior to a CWM intervention in lowering intracranial pressure. The continued improvement over the course of 2 years shows the impact of this intervention with regard to sustained disease remission. Trial Registration: ClinicalTrials.gov Identifier: NCT02124486.

Nicotinamide riboside supplementation does not alter whole-body or skeletal muscle metabolic responses to a single bout of endurance exercise.

KEY POINTS: Acute nicotinamide riboside (NR) supplementation does not alter substrate metabolism at rest, during or in recovery from endurance exercise. NR does not alter NAD+ -sensitive signalling pathways in human skeletal muscle. NR supplementation and acute exercise influence the NAD+ metabolome. ABSTRACT: Oral supplementation of the NAD+ precursor nicotinamide riboside (NR) has been reported to alter metabolism alongside increasing sirtuin (SIRT) signalling and mitochondrial biogenesis in rodent skeletal muscle. However, whether NR supplementation can elicit a similar response in human skeletal muscle is unclear. This study assessed the effect of 7-day NR supplementation on whole-body metabolism and exercise-induced mitochondrial biogenic signalling in skeletal muscle. Eight male participants (age: 23 ± 4 years, V̇O2peak 46.5 ± 4.4 ml kg-1  min-1 ) received 1 week of NR or cellulose placebo (PLA) supplementation (1000 mg day-1 ). Muscle biopsies were collected from the medial vastus lateralis prior to supplementation and pre-, immediately post- and 3 h post-exercise (1 h of 60% Wmax cycling) performed following the supplementation period. There was no effect of NR supplementation on substrate utilisation at rest or during exercise or on skeletal muscle mitochondrial respiration. Global acetylation, auto-PARylation of poly ADP-ribose polymerase 1 (PARP1), acetylation of Tumour protein 53 (p53)Lys382 and Manganese superoxide dismutase (MnSOD)Lys122 were also unaffected by NR supplementation or exercise. NR supplementation did not increase skeletal muscle NAD+ concentration, but it did increase the concentration of deaminated NAD+ precursors nicotinic acid riboside (NAR) and nicotinic acid mononucleotide (NAM) and methylated nicotinamide breakdown products (Me2PY and Me4PY), demonstrating the skeletal muscle bioavailability of NR supplementation. In summary, 1 week of NR supplementation does not alter whole-body metabolism or skeletal muscle signal transduction pathways implicated in the mitochondrial adaptation to endurance exercise.

Metabolic consequences for mice lacking Endosialin: LC-MS/MS-based metabolic phenotyping of serum from C56Bl/6J Control and CD248 knock-out mice.

INTRODUCTION: The Endosialin/CD248/TEM1 protein is expressed in adipose tissue and its expression increases with obesity. Recently, genetic deletion of CD248 has been shown to protect mice against atherosclerosis on a high fat diet. OBJECTIVES: We investigated the effect of high fat diet feeding on visceral fat pads and circulating lipid profiles in CD248 knockout mice compared to controls. METHODS: From 10 weeks old, CD248-/- and +/+ mice were fed either chow (normal) diet or a high fat diet for 13 weeks. After 13 weeks the metabolic profiles and relative quantities of circulating lipid species were assessed using ultra high performance liquid chromatography-quadrupole time-of flight mass spectrometry (UHPLC-MS) with high resolution accurate mass (HRAM) capability. RESULTS: We demonstrate a specific reduction in the size of the perirenal fat pad in CD248-/- mice compared to CD248+/+, despite similar food intake. More strikingly, we identify significant, diet-dependent differences in the serum metabolic phenotypes of CD248 null compared to age and sex-matched wildtype control mice. Generalised protection from HFD-induced lipid accumulation was observed in CD248 null mice compared to wildtype, with particular reduction noted in the lysophosphatidylcholines, phosphatidylcholines, cholesterol and carnitine. CONCLUSIONS: Overall these results show a clear and protective metabolic consequence of CD248 deletion in mice, implicating CD248 in lipid metabolism or trafficking and opening new avenues for further investigation using anti-CD248 targeting agents.

Erenumab for headaches in idiopathic intracranial hypertension: A prospective open-label evaluation.

OBJECTIVE: To determine the effectiveness of erenumab in treating headaches in idiopathic intracranial hypertension (IIH) in whom papilledema had resolved. BACKGROUND: Disability in IIH is predominantly driven by debilitating headaches with no evidence for the use of preventative therapies. Headache therapy in IIH is an urgent unmet need. METHODS: A prospective, open-label study in the United Kingdom was conducted. Adult females with confirmed diagnosis of IIH now in ocular remission (papilledema resolved) with chronic headaches (≥15 days a month) and failure of ≥3 preventative medications received erenumab 4-weekly (assessments were 3-monthly). The primary end point was change in monthly moderate/severe headache days (MmsHD) from baseline (30-day pretreatment period) compared to 12 months. RESULTS: Fifty-five patients, mean (SD) age 35.3 (9) years and mean duration of headaches 10.4 (8.4) years with 3.7 (0.9) preventative treatment failures, were enrolled. Mean baseline MmsHD was 16.1 (4.7) and total monthly headache days (MHD) was (29) 2.3. MmsHD reduced substantially at 12 months by mean (SD) [95% CI] 10.8 (4.0) [9.5, 11.9], p < 0.001 and MHD reduced by 13.0 (9.5) [10.2, 15.7], p < 0.001. Crystal clear days (days without any head pain) increased by 13.1 (9.5) [9.6, 15.3], p < 0.001, headache severity (scale 0-10) fell by 1.3 (1.7) [0.9, 1.9], p < 0.001, and monthly analgesic days reduced by 4.3 (9.2) [1.6, 6.9], p = 0.002. All these measures had improved significantly by 3 months, with a consistent significant response to 12 months. Headache impact test-6 score and quality of life Short Form-36 Health Survey significantly improved at 12 months. Sensitivity analysis revealed similar results for patients with and without a prior migraine diagnosis (28/55 (52%) patients) or those with or without medication overuse (27/55 (48%) patients). CONCLUSIONS: This study provides evidence for the effectiveness of erenumab to treat headaches in IIH patients with resolution of papilledema. It provides mechanistic insights suggesting that calcitonin gene-related peptide is likely a modulator driving headache and a useful therapeutic target.

Local steroid activation is a critical mediator of the anti-inflammatory actions of therapeutic glucocorticoids.

OBJECTIVES: The enzyme 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) plays a well-characterised role in the metabolism and activation of endogenous glucocorticoids (GCs). However, despite its potent upregulation at sites of inflammation, its role in peripheral metabolism and action of therapeutic GCs remains poorly understood. We investigated the contribution of 11ß-HSD1 to the anti-inflammatory properties of the active GC corticosterone, administered at therapeutic doses in murine models of polyarthritis. METHODS: Using the tumour necrosis factor-tg and K/BxN serum-induced models of polyarthritis, we examined the anti-inflammatory properties of oral administration of corticosterone in animals with global, myeloid and mesenchymal targeted transgenic deletion of 11ß-HSD1. Disease activity and joint inflammation were scored daily. Joint destruction and measures of local and systemic inflammation were determined by histology, micro-CT, quantitative RT-PCR, fluorescence activated cell sorting and ELISA. RESULTS: Global deletion of 11ß-HSD1 resulted in a profound GC resistance in animals receiving corticosterone, characterised by persistent synovitis, joint destruction and inflammatory leucocyte infiltration. This was partially reproduced with myeloid, but not mesenchymal 11ß-HSD1 deletion, where paracrine GC signalling between cell populations was shown to overcome targeted deletion of 11ß-HSD1. CONCLUSIONS: We identify an entirely novel component of therapeutic GC action, whereby following their systemic metabolism, they require peripheral reactivation and amplification by 11ß-HSD1 at sites of inflammation to deliver their anti-inflammatory therapeutic effects. This study provides a novel mechanistic understanding of the anti-inflammatory properties of therapeutic GCs and their targeting to sites of inflammation in polyarthritis.

11ßHSD1 Inhibition with AZD4017 Improves Lipid Profiles and Lean Muscle Mass in Idiopathic Intracranial Hypertension.

BACKGROUND: The enzyme 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) determines prereceptor metabolism and activation of glucocorticoids within peripheral tissues. Its dysregulation has been implicated in a wide array of metabolic diseases, leading to the development of selective 11ß-HSD1 inhibitors. We examined the impact of the reversible competitive 11ß-HSD1 inhibitor, AZD4017, on the metabolic profile in an overweight female cohort with idiopathic intracranial hypertension (IIH). METHODS: We conducted a UK multicenter phase II randomized, double-blind, placebo-controlled trial of 12-week treatment with AZD4017. Serum markers of glucose homeostasis, lipid metabolism, renal and hepatic function, inflammation and androgen profiles were determined and examined in relation to changes in fat and lean mass by dual-energy X-ray absorptiometry. RESULTS: Patients receiving AZD4017 showed significant improvements in lipid profiles (decreased cholesterol, increased high-density lipoprotein [HDL] and cholesterol/HDL ratio), markers of hepatic function (decreased alkaline phosphatase and gamma-glutamyl transferase), and increased lean muscle mass (1.8%, P < .001). No changes in body mass index, fat mass, and markers of glucose metabolism or inflammation were observed. Patients receiving AZD4017 demonstrated increased levels of circulating androgens, positively correlated with changes in total lean muscle mass. CONCLUSIONS: These beneficial metabolic changes represent a reduction in risk factors associated with raised intracranial pressure and represent further beneficial therapeutic outcomes of 11ß-HSD1 inhibition by AZD4017 in this overweight IIH cohort. In particular, beneficial changes in lean muscle mass associated with AZD4017 may reflect new applications for this nature of inhibitor in the management of conditions such as sarcopenia.

Calcitonin gene related peptide monoclonal antibody treats headache in patients with active idiopathic intracranial hypertension.

BACKGROUND: Headache is the dominant factor for quality of life related disability in idiopathic intracranial hypertension (IIH) and typically has migraine-like characteristics. There are currently no evidence-based therapeutics for headache in IIH, and consequently this is an important unmet clinical need. CASE SERIES: We report a series of seven patients in whom headaches were the presenting feature of IIH and the headaches had migraine-like characteristics, as is typical in many IIH patients. Papilloedema settled (ocular remission) but headaches continued. These headaches responded markedly to erenumab, a monoclonal antibody targeted against the calcitonin gene related peptide (CGRP) receptor. Of note, there was a recurrence of raised ICP, as evidenced by a return of the papilloedema, however the headaches did not recur whilst treated with erenumab. CONCLUSIONS: Those with prior IIH who have their headaches successfully treated with CGRP therapy, should remain under close ocular surveillance (particularly when weight gain is evident) as papilloedema can re-occur in the absence of headache. These cases may suggest that CGRP could be a mechanistic driver for headache in patients with active IIH.

11ß-Hydroxysteroid dehydrogenase type 1 inhibition in idiopathic intracranial hypertension: a double-blind randomized controlled trial.

Treatment options for idiopathic intracranial hypertension are limited. The enzyme 11ß-hydroxysteroid dehydrogenase type 1 has been implicated in regulating cerebrospinal fluid secretion, and its activity is associated with alterations in intracranial pressure in idiopathic intracranial hypertension. We assessed therapeutic efficacy, safety and tolerability and investigated indicators of in vivo efficacy of the 11ß-hydroxysteroid dehydrogenase type 1 inhibitor AZD4017 compared with placebo in idiopathic intracranial hypertension. A multicenter, UK, 16-week phase II randomized, double-blind, placebo-controlled trial of 12-week treatment with AZD4017 or placebo was conducted. Women aged 18-55 years with active idiopathic intracranial hypertension (>25 cmH2O lumbar puncture opening pressure and active papilledema) were included. Participants received 400 mg of oral AZD4017 twice daily compared with matching placebo over 12 weeks. The outcome measures were initial efficacy, safety and tolerability. The primary clinical outcome was lumbar puncture opening pressure at 12 weeks analysed by intention-to-treat. Secondary clinical outcomes were symptoms, visual function, papilledema, headache and anthropometric measures. In vivo efficacy was evaluated in the central nervous system and systemically. A total of 31 subjects [mean age 31.2 (SD = 6.9) years and body mass index 39.2 (SD = 12.6) kg/m2] were randomized to AZD4017 (n = 17) or placebo (n = 14). At 12 weeks, lumbar puncture pressure was lower in the AZD4017 group (29.7 cmH2O) compared with placebo (31.3 cmH2O), but the difference between groups was not statistically significant (mean difference: -2.8, 95% confidence interval: -7.1 to 1.5; P = 0.2). An exploratory analysis assessing mean change in lumbar puncture pressure within each group found a significant decrease in the AZD4017 group [mean change: -4.3 cmH2O (SD = 5.7); P = 0.009] but not in the placebo group [mean change: -0.3 cmH2O (SD = 5.9); P = 0.8]. AZD4017 was safe, with no withdrawals related to adverse effects. Nine transient drug-related adverse events were reported. One serious adverse event occurred in the placebo group (deterioration requiring shunt surgery). In vivo biomarkers of 11ß-hydroxysteroid dehydrogenase type 1 activity (urinary glucocorticoid metabolites, hepatic prednisolone generation, serum and cerebrospinal fluid cortisol:cortisone ratios) demonstrated significant enzyme inhibition with the reduction in serum cortisol:cortisone ratio correlating significantly with reduction in lumbar puncture pressure (P = 0.005, R = 0.70). This is the first phase II randomized controlled trial in idiopathic intracranial hypertension evaluating a novel therapeutic target. AZD4017 was safe and well tolerated and inhibited 11ß-hydroxysteroid dehydrogenase type 1 activity in vivo. Reduction in serum cortisol:cortisone correlated with decreased intracranial pressure. Possible clinical benefits were noted in this small cohort. A longer, larger study would now be of interest.

Emerging themes in idiopathic intracranial hypertension.

PURPOSE: Idiopathic intracranial hypertension (IIH) is a rare disorder characterised by raised intracranial pressure. The underlying pathophysiology is mostly unknown and effective treatment is an unmet clinical need in this disease. This review evaluates key emerging themes regarding disease characteristics, mechanisms contributing to raised intracranial pressure and advances in potential therapeutic targets. FINDINGS: IIH is becoming more common, with the incidence rising in parallel with the global obesity epidemic. Current medical management remains centred around weight management, which is challenging. Metabolic investigations of patients have identified specific androgen profiles in cerebrospinal fluid (CSF), which suggest an endocrine dysfunction impacting CSF secretion in IIH. Glucagon-like peptide-1 (GLP-1) and 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) have been found to play a role in CSF dynamics in IIH and have formed the basis of the first clinical trials looking at new treatments. CONCLUSIONS: Identification of novel molecular targets thought to underlie IIH pathology is now being translated to clinical trials.

AMPK activation induces mitophagy and promotes mitochondrial fission while activating TBK1 in a PINK1-Parkin independent manner.

Mitophagy is a key process regulating mitochondrial quality control. Several mechanisms have been proposed to regulate mitophagy, but these have mostly been studied using stably expressed non-native proteins in immortalized cell lines. In skeletal muscle, mitophagy and its molecular mechanisms require more thorough investigation. To measure mitophagy directly, we generated a stable skeletal muscle C2C12 cell line, expressing a mitophagy reporter construct (mCherry-green fluorescence protein-mtFIS1101-152 ). Here, we report that both carbonyl cyanide m-chlorophenyl hydrazone (CCCP) treatment and adenosine monophosphate activated protein kinase (AMPK) activation by 991 promote mitochondrial fission via phosphorylation of MFF and induce mitophagy by ~20%. Upon CCCP treatment, but not 991, ubiquitin phosphorylation, a read-out of PTEN-induced kinase 1 (PINK1) activity, and Parkin E3 ligase activity toward CDGSH iron sulfur domain 1 (CISD1) were increased. Although the PINK1-Parkin signaling pathway is active in response to CCCP treatment, we observed no change in markers of mitochondrial protein content. Interestingly, our data shows that TANK-binding kinase 1 (TBK1) phosphorylation is increased after both CCCP and 991 treatments, suggesting TBK1 activation to be independent of both PINK1 and Parkin. Finally, we confirmed in non-muscle cell lines that TBK1 phosphorylation occurs in the absence of PINK1 and is regulated by AMPK-dependent signaling. Thus, AMPK activation promotes mitophagy by enhancing mitochondrial fission (via MFF phosphorylation) and autophagosomal engulfment (via TBK1 activation) in a PINK1-Parkin independent manner.