Heterozygous pathogenic variants in POMC are not responsible for monogenic obesity: Implication for MC4R agonist use.

PURPOSE: Recessive deficiency of proopiomelanocortin (POMC) causes childhood-onset severe obesity. Cases can now benefit from the melanocortin 4 receptor agonist setmelanotide. Furthermore, a phase 3 clinical trial is evaluating setmelanotide in heterozygotes for POMC. We performed a large-scale genetic analysis to assess the effect of heterozygous, pathogenic POMC variants on obesity. METHODS: A genetic analysis was performed in a family including 2 cousins with childhood-onset obesity. We analyzed the obesity status of heterozygotes for pathogenic POMC variants in the Human Gene Mutation Database. The association between heterozygous pathogenic POMC variants and obesity risk was assessed using 190,000 exome samples from UK Biobank. RESULTS: The 2 cousins carried a compound heterozygous pathogenic variant in POMC. Six siblings were heterozygotes; only 1 of them had obesity. In Human Gene Mutation Database, we identified 60 heterozygotes for pathogenic POMC variants, of whom 14 had obesity. In UK Biobank, heterozygous pathogenic POMC variants were not associated with obesity risk, but they modestly increased body mass index levels. CONCLUSION: Heterozygous pathogenic POMC variants do not contribute to monogenic obesity, but they slightly increase body mass index. Setmelanotide use in patients with obesity, which would only be based on the presence of a heterozygous POMC variant, can be questioned.

Novel therapeutics in rare genetic obesities: A narrative review.

The better understanding of the molecular causes of rare genetic obesities and its associated phenotype involving the hypothalamus allows today to consider innovative therapeutics focused on hunger control. Several new pharmacological molecules benefit patients with monogenic or syndromic obesity. They are likely to be among the treatment options for these patients in the coming years, helping clinicians and patients prevent rapid weight progression and eventually limit bariatric surgery procedures, which is less effective in these patients. Their positioning in the management of such patients will be needed to be well defined to develop precision medicine in genetic forms of obesity.

Therapeutic indications and metabolic effects of metreleptin in patients with lipodystrophy syndromes: Real-life experience from a national reference network.

AIM: To describe baseline characteristics and follow-up data in patients with lipodystrophy syndromes treated with metreleptin in a national reference network, in a real-life setting. PATIENTS AND METHODS: Clinical and metabolic data from patients receiving metreleptin in France were retrospectively collected, at baseline, at 1 year and at the latest follow-up during treatment. RESULTS: Forty-seven patients with lipodystrophy including generalized lipodystrophy (GLD; n = 28) and partial lipodystrophy (PLD; n = 19) received metreleptin over the last decade. At baseline, the median (interquartile range [IQR]) patient age was 29.3 (16.6-47.6) years, body mass index was 23.8 (21.2-25.7) kg/m2 and serum leptin was 3.2 (1.0-4.9) ng/mL, 94% of patients had diabetes (66% insulin-treated), 53% had hypertension and 87% had dyslipidaemia. Metreleptin therapy, administered for a median (IQR) of 31.7 (14.2-76.0) months, was ongoing in 77% of patients at the latest follow-up. In patients with GLD, glycated haemoglobin (HbA1c) and fasting triglyceride levels significantly decreased from baseline to 1 year of metreleptin treatment, from 8.4 (6.5-9.9)% [68 (48-85) mmol/mol] to 6.8 (5.6-7.4)% [51(38-57) mmol/mol], and 3.6 (1.7-8.5) mmol/L to 2.2 (1.1-3.7) mmol/L, respectively (P < 0.001), with sustained efficacy thereafter. In patients with PLD, HbA1c was not significantly modified (7.7 [7.1-9.1]% [61 (54-76) mmol/mol] at baseline vs. 7.7 [7.4-9.5]% [61(57-80) mmol/mol] at 1 year), and the decrease in fasting triglycerides (from 3.3 [1.9-9.9] mmol/L to 2.5 [1.6-5.3] mmol/L; P < 0.01) was not confirmed at the latest assessment (5.2 [2.2-11.3] mmol/L). However, among PLD patients, at 1 year, 61% were responders regarding glucose homeostasis, with lower baseline leptin levels compared to nonresponders, and 61% were responders regarding triglyceridaemia. Liver enzymes significantly decreased only in the GLD group. CONCLUSIONS: In this real-life setting study, metabolic outcomes are improved by metreleptin therapy in patients with GLD. The therapeutic indication for metreleptin needs to be clarified in patients with PLD.

Senescence-associated ß-galactosidase in subcutaneous adipose tissue associates with altered glycaemic status and truncal fat in severe obesity.

AIM/HYPOTHESIS: Altered adipose tissue secretory profile contributes to insulin resistance and type 2 diabetes in obesity. Preclinical studies have identified senescent cells as a cellular source of proinflammatory factors in adipose tissue of obese mice. In humans, potential links with obesity comorbidities are poorly defined. Here, we investigated adipose tissue senescent status and relationships with metabolic complications in human obesity. METHODS: The study includes a prospective cohort of 227 individuals with severe obesity. A photometric method was used to quantify senescence-associated ß-galactosidase (SA-ß-gal) activity in paired subcutaneous and omental adipose tissue biopsies obtained during gastric surgery. Gene and secretory profiling was performed in adipose tissue biopsies and in human primary pre-adipocytes in the presence or absence of senolytic drugs targeting senescent cells. Participants were phenotyped for anthropometric and bioclinical variables, metabolic complications and gastric surgery-induced improvement to address relationships with adipose tissue SA-ß-gal. RESULTS: SA-ß-gal activity was sevenfold higher in subcutaneous than in omental adipose tissue and not associated with BMI or chronological age. Several factors, including insulin-like growth factor binding protein 3 (IGFBP3), plasminogen activator inhibitor 1 (PAI1), C-C motif chemokine ligand 2 (CCL2) and IL-6, were upregulated in subcutaneous adipose tissue in relation with SA-ß-gal (p for linear trend across tertiles <0.05) and in pre-adipocytes cultured with inflammatory macrophage conditioned media. Senolytic treatment reduced SA-ß-gal staining and normalised these alterations. In the whole population, subcutaneous adipose tissue SA-ß-gal activity was positively associated with serum leptin, markers of insulin resistance and increased trunk fat mass. Metabolic complications, including type 2 diabetes and dyslipidaemia, were more prevalent in patients with high levels of SA-ß-gal, but improved with bariatric surgery whatever the initial adipose tissue senescent status. CONCLUSIONS/INTERPRETATION: This study highlights a phenotype of senescence in adipose tissue of severely obese individuals, which characterises prominently subcutaneous fat depots. Subcutaneous adipose tissue senescence is significantly linked to altered glucose metabolism and body fat distribution. Elimination of senescent cells through senolytic treatment could alleviate metabolic complications in severely obese people. Graphical abstract.

Type 2 diabetes is associated with impaired jejunal enteroendocrine GLP-1 cell lineage in human obesity.

OBJECTIVES: Altered enteroendocrine cell (EEC) function in obesity and type 2 diabetes is not fully understood. Understanding the transcriptional program that controls EEC differentiation is important because some EEC types harbor significant therapeutic potential for type 2 diabetes. METHODS: EEC isolation from jejunum of obese individuals with (ObD) or without (Ob) type 2 diabetes was obtained with a new method of cell sorting. EEC transcriptional profiles were established by RNA-sequencing in a first group of 14 Ob and 13 ObD individuals. EEC lineage and densities were studied in the jejunum of a second independent group of 37 Ob, 21 ObD and 22 non obese (NOb) individuals. RESULTS: The RNA seq analysis revealed a distinctive transcriptomic signature and a decreased differentiation program in isolated EEC from ObD compared to Ob individuals. In the second independent group of ObD, Ob and NOb individuals a decreased GLP-1 cell lineage and GLP-1 maturation from proglucagon, were observed in ObD compared to Ob individuals. Furthermore, jejunal density of GLP-1-positive cells was significantly reduced in ObD compared to Ob individuals. CONCLUSIONS: These results highlight that the transcriptomic signature of EEC discriminate obese subjects according to their diabetic status. Furthermore, type 2 diabetes is associated with reduced GLP-1 cell differentiation and proglucagon maturation leading to low GLP-1-cell density in human obesity. These mechanisms could account for the decrease plasma GLP-1 observed in metabolic diseases.

A Melanocortin-4 Receptor Agonist Induces Skin and Hair Pigmentation in Patients with Monogenic Mutations in the Leptin-Melanocortin Pathway.

BACKGROUND AND OBJECTIVES: Gene mutations within the leptin-melanocortin signaling pathway lead to severe early-onset obesity. Recently, a phase 2 trial evaluated new pharmacological treatment options with the MC4R agonist setmelanotide in patients with mutations in the genes encoding proopiomelanocortin (POMC) and leptin receptor (LEPR). During treatment with setmelanotide, changes in skin pigmentation were observed, probably due to off-target effects on the closely related melanocortin 1 receptor (MC1R). Here, we describe in detail the findings of dermatological examinations and measurements of skin pigmentation during this treatment over time and discuss the impact of these changes on patient safety. METHODS: In an investigator-initiated, phase 2, open-label pilot study, 2 patients with loss-of-function POMC gene mutations and 3 patients with loss-of-function variants in LEPR were treated with the MC4R agonist setmelanotide. Dermatological examination, dermoscopy, whole body photographic documentation, and spectrophotometric measurements were performed at screening visit and approximately every 3 months during the course of the study. RESULTS: We report the results of a maximum treatment duration of 46 months. Skin pigmentation increased in all treated patients, as confirmed by spectrophotometry. During continuous treatment, the current results indicate that elevated tanning intensity levels may stabilize over time. Lips and nevi also darkened. In red-haired study participants, hair color changed to brown after initiation of setmelanotide treatment. DISCUSSION: Setmelanotide treatment leads to skin tanning and occasionally hair color darkening in both POMC- and LEPR-deficient patients. No malignant skin changes were observed in the patients of this study. However, the results highlight the importance of regular skin examinations before and during MC4R agonist treatment.

Gut microbiota of obese subjects with Prader-Willi syndrome is linked to metabolic health.

OBJECTIVE: The gut microbiota has been implicated in the aetiology of obesity and associated comorbidities. Patients with Prader-Willi syndrome (PWS) are obese but partly protected against insulin resistance. We hypothesised that the gut microbiota of PWS patients differs from that of non-genetically obese controls and correlate to metabolic health. Therefore, here we used PWS as a model to study the role of gut microbiota in the prevention of metabolic complications linked to obesity. DESIGN: We conducted a case-control study with 17 adult PWS patients and 17 obese subjects matched for body fat mass index, gender and age. The subjects were metabolically characterised and faecal microbiota was profiled by 16S ribosomal RNA gene sequencing. The patients' parents were used as a non-obese control group. Stool samples from two PWS patients and two obese controls were used for faecal microbiota transplantations in germ-free mice to examine the impact of the microbiota on glucose metabolism. RESULTS: The composition of the faecal microbiota in patients with PWS differed from that of obese controls, and was characterised by higher phylogenetic diversity and increased abundance of several taxa such as Akkermansia, Desulfovibrio and Archaea, and decreased abundance of Dorea. Microbial taxa prevalent in the PWS microbiota were associated with markers of insulin sensitivity. Improved insulin resistance of PWS was partly transmitted by faecal microbiota transplantations into germ-free mice. CONCLUSION: The gut microbiota of PWS patients is similar to that of their non-obese parents and might play a role for the protection of PWS patients from metabolic complications.

Increasing physical activity in adult women with Prader-Willi syndrome: A transferability study.

BACKGROUND: The present authors aimed (a) to objectively quantify spontaneous physical activity (PA) in adult patients with Prader-Willi syndrome (PWS) and (b) to evaluate the transferability of a home-based exercise training programme in these patients. METHOD: Physical activity was compared between 10 adult women with PWS (PWS group) and 20 adult women with non-syndromic obesity (CON group, for cross-sectional comparison). In the PWS group, PA, body composition, walking capacity, quality of life and eating behaviour were then compared before and after a 16-week supervised exercise programme. RESULTS: The PWS group displayed lower PA and higher sedentary time compared to the CON group. Median attendance to exercise sessions reached 100% (Q1-Q3: 97%-100%) sessions. Moderate-to-vigorous PA and walking capacity increased after the programme without significant effect on body composition. CONCLUSION: Supervised home-based exercise sessions are an effective strategy to improve PA in women with PWS who are less active than women matched for adiposity.

Mucosal-associated invariant T (MAIT) cells are depleted and prone to apoptosis in cardiometabolic disorders.

The disruption of systemic immune homeostasis is a key mediator in the progression of cardiometabolic diseases (CMDs). We aimed to extend knowledge regarding the clinical relevance of CMD-associated variation of circulating mucosal-associated invariant T (MAIT) cell abundance and to explore underlying cellular mechanisms. We analyzed cross-sectional data from 439 participants of the Metagenomics in Cardiometabolic Diseases (MetaCardis) study, stratified into 6 groups: healthy control subjects and patients with metabolic syndrome (MS), obesity, type 2 diabetes mellitus (T2DM), and coronary artery disease (CAD) without, or with congestive heart failure (CAD-CHF). Blood MAIT cell frequency was significantly decreased in all CMD groups, including early (MS) and later (CAD and CAD-CHF) stages of disease progression. Reduced MAIT cell abundance was associated with increased glycosylated hemoglobin, inflammation markers, and deterioration of cardiac function. Glucose dose dependently promoted MAIT cell apoptosis in vitro, independently of anti-CD3 and cytokine-mediated activation. This outcome suggests the prominence of metabolic over an antigenic or cytokine-rich environment to promote MAIT cell reduction in patients with CMD. In summary, all stages of CMDs are characterized by reduced circulating MAIT cells. Chronically elevated blood glucose levels could contribute to this decline. These data extend the pathologic relevance of MAIT cell loss and suggest that MAIT cell abundance may serve as an indicator of cardiometabolic health.-Touch, S., Assmann, K. E., Aron-Wisnewsky, J., Marquet, F., Rouault, C., Fradet, M., Mosbah, H., MetaCardis Consortium, Isnard, R., Helft, G., Lehuen, A., Poitou, C., Clément, K., André, S. Mucosal-associated invariant T (MAIT) cells are depleted and prone to apoptosis in cardiometabolic disorders.

Increased jejunal permeability in human obesity is revealed by a lipid challenge and is linked to inflammation and type 2 diabetes.

Obesity and its metabolic complications are characterized by subclinical systemic and tissue inflammation. In rodent models of obesity, inflammation and metabolic impairments are linked with intestinal barrier damage. However, whether intestinal permeability is altered in human obesity remains to be investigated. In a cohort of 122 severely obese and non-obese patients, we analyzed intestinal barrier function combining in vivo and ex vivo investigations. We found tight junction impairments in the jejunal epithelium of obese patients, evidenced by a reduction of occludin and tricellulin. Serum levels of zonulin and LPS binding protein, two markers usually associated with intestinal barrier alterations, were also increased in obese patients. Intestinal permeability per se was assessed in vivo by quantification of urinary lactitol/mannitol (L/M) and measured directly ex vivo on jejunal samples in Ussing chambers. In the fasting condition, L/M ratio and jejunal permeability were not significantly different between obese and non-obese patients, but high jejunal permeability to small molecules (0.4 kDa) was associated with systemic inflammation within the obese cohort. Altogether, these results suggest that intestinal barrier function is subtly compromised in obese patients. We thus tested whether this barrier impairment could be exacerbated by dietary lipids. To this end, we challenged jejunal samples with lipid micelles and showed that a single exposure increased permeability to macromolecules (4 kDa). Jejunal permeability after the lipid load was two-fold higher in obese patients compared to non-obese controls and correlated with systemic and intestinal inflammation. Moreover, lipid-induced permeability was an explicative variable of type 2 diabetes. In conclusion, intestinal barrier defects are present in human severe obesity and exacerbated by a lipid challenge. This paves the way to the development of novel therapeutic approaches to modulate intestinal barrier function or personalize nutrition therapy to decrease lipid-induced jejunal leakage in metabolic diseases. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Systematic review of bariatric surgery liver biopsies clarifies the natural history of liver disease in patients with severe obesity.

OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is a frequent complication of morbid obesity, but its severity varies greatly and thus there is a strong need to better define its natural history in these patients. DESIGN: Liver biopsies were systematically performed in 798 consecutive patients with severe obesity undergoing bariatric surgery. Histology was compared with clinical, biological, anthropometrical and body composition characteristics. RESULTS: Patients with presumably normal liver (n=179, 22%) were significantly younger at bariatric surgery than patients with NAFLD (37.0 vs 44.4 years, p<0.0001). However, both groups showed quite similar obesity duration, since patients with presumably normal liver reported the onset of obesity at a significantly younger age than those with NAFLD (14.8 vs 20.0 year, p<0.0001). The trunk/limb fat mass ratio increased according to liver disease severity (presumably normal liver: 1.00, steatosis: 1.21, non-alcoholic steatohepatitis (NASH): 1.34, p<0.0001), although the total body fat mass decreased (presumably normal liver: 50%, steatosis: 49.1%, NASH: 47.4%, p<0.0001). The volume of subcutaneous adipocytes increased according to severity of liver disease but only in female patients (presumably normal liver: 8543 picolitres, steatosis: 9156 picolitres, NASH: 9996 picolitres). CONCLUSIONS: These results suggest that young adults are more prone to store fat in subcutaneous tissue and reach the threshold of bariatric surgery indication before their liver is damaged. A shift of fat storage from subcutaneous to visceral adipose tissue compartment is associated with liver damages. Liver might also be targeted by subcutaneous hypertrophic adipocytes in females since hypertrophic adipocytes are more exposed to lipolysis and to the production of inflammatory mediators.

The advanced-DiaRem score improves prediction of diabetes remission 1 year post-Roux-en-Y gastric bypass.

AIMS/HYPOTHESIS: Not all people with type 2 diabetes who undergo bariatric surgery achieve diabetes remission. Thus it is critical to develop methods for predicting outcomes that are applicable for clinical practice. The DiaRem score is relevant for predicting diabetes remission post-Roux-en-Y gastric bypass (RYGB), but it is not accurate for all individuals across the entire spectrum of scores. We aimed to develop an improved scoring system for predicting diabetes remission following RYGB (the Advanced-DiaRem [Ad-DiaRem]). METHODS: We used a retrospective French cohort (n = 1866) that included 352 individuals with type 2 diabetes followed for 1 year post-RYGB. We developed the Ad-DiaRem in a test cohort (n = 213) and examined its accuracy in independent cohorts from France (n = 134) and Israel (n = 99). RESULTS: Adding two clinical variables (diabetes duration and number of glucose-lowering agents) to the original DiaRem and modifying the penalties for each category led to improved predictive performance for Ad-DiaRem. Ad-DiaRem displayed improved area under the receiver operating characteristic curve and predictive accuracy compared with DiaRem (0.911 vs 0.856 and 0.841 vs 0.789, respectively; p = 0.03); thus correcting classification for 8% of those initially misclassified with DiaRem. With Ad-DiaRem, there were also fewer misclassifications of individuals with mid-range scores. This improved predictive performance was confirmed in independent cohorts. CONCLUSIONS/INTERPRETATION: We propose the Ad-DiaRem, which includes two additional clinical variables, as an optimised tool with improved accuracy to predict diabetes remission 1 year post-RYGB. This tool might be helpful for personalised management of individuals with diabetes when considering bariatric surgery in routine care, ultimately contributing to precision medicine.

The effect of morbid obesity on morphine glucuronidation.

The purpose of the present work was to study the change in morphine metabolic ratio in obese subjects before and after Roux-en-Y Gastric Bypass (RYGB) and to identify clinical and/or biological factors associated with this change. The pharmacokinetics (PK) of oral morphine (30mg), morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) was performed in patients before (n=25; mean BMI=43.2 (35.4-61.9)kg/m2), 7-15days (n=16) and 6 months after RYGB (n=19; mean BMI=32.3 (25.4-46.0)kg/m2). Morphine Cmax and AUC0-inf were significantly increased and morphine Tmax significantly shortened at 6 months after RYGB compared with preoperative data, indicating an important increase in the rate and extent of morphine absorption. The morphine metabolic ratio 0-inf M3G+M6G/Morphine, decreased significantly from the preoperative to 6 months postoperative period with an average of -26% (range -74%; +21%; p=0.004), but not in the immediate post-operative period. The change in morphine metabolic ratio was associated with a change in BMI, fat mass in kg, and triglyceride levels (rho=0.5, p≤0.04). The degree of change in several markers of low-grade inflammation, or the level of liver steatosis and fibrosis before surgery, was not associated with the change in morphine metabolic ratios. Our findings indicate that RYGB-induced weight loss significantly decreases morphine metabolic ratio, arguing for an effect of morbid obesity on glucuronidation. With glucuronide exposure at 6 months similar to preoperative values, a higher morphine AUC0-inf should encourage reducing morphine dosage in patients undergoing RYGB and chronically receiving immediate-release oral morphine.

Profiling of the three circulating monocyte subpopulations in human obesity.

Three subpopulations of circulating monocytes have been described: CD14(2+)CD16(-) (classical monocytes [CM]), CD14(2+)CD16(+) (intermediate monocytes [IM]), and CD14(+)CD16(2+) (nonclassical monocytes [NCM]). We previously showed that obesity is associated with an increased proportion of IM and NCM. Our objective is to decipher the migratory and inflammatory functions of each monocyte subset in obesity-related low-grade inflammation. Twenty-six healthy, normal-weight and nondiabetic volunteers (C) and 40 obese nondiabetic (Ob) individuals were included in this study. We explored the gene expression profile of 18 inflammatory genes in each subset of C and Ob subjects and measured protein expression of the upregulated genes. We then tested their functional response to TLR signaling in both groups. We showed an increased expression of CX3CR1 in all monocyte subpopulations and of CCR2 and CCR5 in CM and IM in the Ob group. We found negative correlation between CCR2 and CX3CR1 expressions and high-density lipoprotein-cholesterol, whereas CCR5 expression was positively linked to obesity-related metabolic traits. Production of inflammatory proteins upon bacterial LPS and viral ssRNA stimulation was higher in CM and NCM of the Ob group compared with the C group. Our work highlights an enhanced inflammatory phenotype of monocytes with a higher response to TLR4 and TLR8 stimulations in obesity. Moreover, it suggests an increased migration capacity of CM and IM subpopulations.

Oral Morphine Pharmacokinetic in Obesity: The Role of P-Glycoprotein, MRP2, MRP3, UGT2B7, and CYP3A4 Jejunal Contents and Obesity-Associated Biomarkers.

The objective of our work was to study the association between the jejunal expression levels of P-gp, MRP2, MRP3, UGT2B7, CYP3A4, the ABCB1 c.3435C > T polymorphism, and several obesity-associated biomarkers, as well as oral morphine and glucuronides pharmacokinetics in a population of morbidly obese subjects. The pharmacokinetics of oral morphine (30 mg) and its glucuronides was performed in obese patients candidate to bariatric surgery. A fragment of jejunal mucosa was preserved during surgery. Subjects were genotyped for the ABCB1 single nucleotide polymorphism (SNP) c.3435C > T. The subjects were 6 males and 23 females, with a mean body mass index of 44.8 (35.4-61.9) kg/m(2). The metabolic ratios AUC0-inf M3G/morphine and AUC0-inf M6G/morphine were highly correlated (rs = 0.8, p < 0.0001) and were 73.2 ± 24.6 (34.7-137.7) and 10.9 ± 4.1 (3.8-20.6). The pharmacokinetic parameters of morphine and its glucuronides were not associated with the jejunal contents of P-gp, CYP3A4, MRP2, and MRP3. The jejunal content of UGT2B7 was positively associated with morphine AUC0-inf (rs = 0.4, p = 0.03). Adiponectin was inversely correlated with morphine Cmax (rs = -0.44, p = 0.03). None of the factors studied was associated with morphine metabolic ratios. The interindividual variability in the jejunal content of drug transporters and metabolizing enzymes, the ABCB1 gene polymorphism, and the low-grade inflammation did not explain the variability in morphine and glucuronide exposure. High morphine metabolic ratio argued for an increased morphine glucuronidation in morbidly obese patients.

Quantitative Atlas of Cytochrome P450, UDP-Glucuronosyltransferase, and Transporter Proteins in Jejunum of Morbidly Obese Subjects.

Protein expression levels of drug-metabolizing enzymes and transporters in human jejunal tissues excised from morbidly obese subjects during gastric bypass surgery were evaluated using quantitative targeted absolute proteomics. Protein expression levels of 15 cytochrome P450 (CYP) enzymes, 10 UDP-glucuronosyltransferase (UGT) enzymes, and NADPH-P450 reductase (P450R) in microsomal fractions from 28 subjects and 49 transporters in plasma membrane fractions from 24 of the same subjects were determined using liquid chromatography-tandem mass spectrometry. Based on average values, UGT1A1, UGT2B15, UGT2B17, SGLT1, and GLUT2 exhibited high expression levels (over 10 fmol/µg protein), though UGT2B15 expression was detected at a high level in only one subject. CYP2C9, CYP2D6, CYP3A5, UGT1A6, P450R, ABCG2, GLUT5, PEPT1, MCT1, 4F2 cell-surface antigen heavy chain (4F2hc), LAT2, OSTα, and OSTß showed intermediate levels (1-10 fmol/µg protein), and CYP1A1, CYP1A2, CYP1B1, CYP2C18, CYP2C19, CYP2J2, CYP3A7, CYP4A11, CYP51A1, UGT1A3, UGT1A4, UGT1A8, UGT2B4, ABCC1, ABCC4, ABCC5, ABCC6, ABCG8, TAUT, OATP2A1, OATP2B1, OATP3A1, OATP4A1, OCTN1, CNT2, PCFT, MCT4, GLUT4, and SLC22A18 showed low levels (less than 1 fmol/µg protein). The greatest interindividual difference (364-fold) was detected for UGT2B17. However, differences in expression levels of other quantified UGTs (except UGT2B15 and UGT2B17), CYPs (except CYP1A1 and CYP3A5), and P450R, and all quantified transporters, were within 10-fold. Expression levels of CYP1A2 and GLUT4 were significantly correlated with body-mass index. The levels of 4F2hc showed significant gender differences. Smokers showed increased levels of UGT1A1 and UGT1A3. These findings provide a basis for understanding the changes in molecular mechanisms of jejunal metabolism and transport, as well as their interindividual variability, in morbidly obese patients.

Circulating phospholipid profiling identifies portal contribution to NASH signature in obesity.

BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH) is characterized by steatosis, lobular inflammation, hepatocyte ballooning with fibrosis in severe cases, and high prevalence in obesity. We aimed at defining NASH signature in morbid obesity by mass spectrometry-based lipidomic analysis. METHODS: We analyzed systemic blood before and 12 months after bariatric surgery, along with portal blood and adipose tissue lipid efflux collected from obese women at the time of surgery (9 structural classes, 150 species). RESULTS: Increased concentrations of several glycerophosphocholines (PC), glycerophosphoethanolamines (PE), glycerophosphoinositols (PI), glycerophosphoglycerols (PG), lyso-glycerophosphocholines (LPC), and ceramides (Cer) were detected in systemic circulation of NASH subjects. Post-surgery weight loss (12 months) improved the levels of liver enzymes, as well as several lipids, but most PG and Cer species remained elevated. Analysis of lipids from hepatic portal system at the time of surgery revealed limited lipid alterations compared to systemic circulation, but PG and PE classes were found significantly increased in NASH subjects. We evaluated the contribution of visceral adipose tissue to lipid alterations in portal circulation by measuring adipose tissue lipid efflux ex vivo, and observed only minor alterations in NASH subjects. Interestingly, integration of clinical and lipidomic data (portal and systemic) led us to define a NASH signature in which lipids and clinical parameters are equal contributors. CONCLUSIONS: Circulatory (portal and systemic) phospholipid profiling and clinical data defines NASH signature in morbid obesity. We report weak contribution of visceral adipose tissue to NASH-related portal lipid alterations, suggesting possible contribution from other organs draining into hepatic portal system.

Macrophage activation marker soluble CD163 and non-alcoholic fatty liver disease in morbidly obese patients undergoing bariatric surgery.

BACKGROUND AND AIMS: Macrophages play an important role in non-alcoholic fatty liver disease (NAFLD). Soluble CD163 (sCD163) is a specific marker of macrophage activation. We aimed to measure sCD163 in morbidly obese patients with varying degrees of NAFLD before and after bariatric surgery (BS). METHODS: Demographic, clinical, and biochemical data, and plasma sCD163 measured by enzyme-linked immunosorbent assay, of 196 patients were collected preoperatively and 3, 6, and 12 months after BS leading to significant weight loss. Peroperative liver biopsies were assessed for the NAFLD Activity Score (NAS), Kleiner fibrosis score, and the fatty liver inhibition of progression (FLIP) algorithm. In a subset, CD163 immunohistochemistry and real-time quantitative polymerase chain reaction for CD163 mRNA were performed. RESULTS: sCD163 was higher in patients with NAS ≥ 5 compared with those with NAS < 5 (2.4(2.0-3.1) vs 1.9(1.5-2.3) mg/L, P < 0.001) and in patients with bridging fibrosis (F ≥ 3) compared with lower fibrosis stages (2.6(2.0-4.9) vs 2.0(1.5-2.4) mg/L, P = 0.001). Preoperative sCD163 was independently associated with both the NAS (P = 0.002) and the fibrosis score (P = 0.024). sCD163 decreased after BS and was greatly reduced after 12 months, more rapidly so in patients with NAS ≥ 5 (P < 0.001) and non-alcoholic steatohepatitis (NASH) according to the FLIP algorithm (P = 0.03). Immunohistochemistry showed CD163-positive macrophages aligning fat-laden hepatocytes and forming microgranulomas in patients with NASH. CD163 mRNA expression did not vary with NAS. CONCLUSION: sCD163 increased in parallel with the severity of NAFLD in morbid obesity, indicating macrophage activation. BS reduced sCD163 even in patients with severe liver injury and fibrosis, suggesting full reversibility of macrophage activation associated with improved insulin sensitivity.

Hyperphagia and impulsivity: use of self-administered Dykens' and in-house impulsivity questionnaires to characterize eating behaviors in children with severe and early-onset obesity.

BACKGROUND: The determinants of early-onset obesity (< 6 years) are not completely elucidated, however eating behavior has a central role. To date no study has explored eating behavior in children with severe, early-onset obesity. Self-administered questionnaire data from these children were examined to evaluate eating behavior and the etiology of early-onset obesity. METHODS: Children with severe, early-onset obesity (body mass index [BMI] > International Obesity Task Force [IOTF] 30) of different etiologies (hypothalamic obesity [HO], intellectual disability with obesity [IDO], common polygenic obesity [CO]) were prospectively included. BMI history and responses from the Dykens' Hyperphagia Questionnaire and an in-house Impulsivity Questionnaire at first visit were compared between groups. RESULTS: This cohort of 75 children (39 girls; mean age ± standard deviation [SD] 10.8 ± 4.4 years) had severe, early-onset obesity at an age of 3.8 ± 2.7 years, with a BMI Z-score of 4.9 ± 1.5. BMI history varied between the 3 groups, with earlier severe obesity in the HO group versus 2 other groups (BMI > IOTF40 at 3.4 ± 1.6 vs. 4.6 ± 1.6 and 8.4 ± 4.1 years for the IDO and CO groups, respectively [P < 0.01]). Absence of adiposity rebound was more prevalent in the HO group (87% vs. 63% and 33% for the IDO and CO groups, respectively [P < 0.01]). The Dykens' mean total score for the cohort was 22.1 ± 7.2 with no significant between-group differences. Hyperphagia (Dykens' score > 19) and impulsivity (score > 7) were found in 50 (67%) and 11 children (15%), respectively, with no difference between the HO, IDO and CO groups regarding the number of patients with hyperphagia (10 [67%], 14 [74%], and 26 [63%] children, respectively) or impulsivity (2 [13%], 1 [7%], and 8 [19%] children, respectively). Children with food impulsivity had significantly higher total and severity scores on the Dykens' Questionnaire versus those without impulsivity. CONCLUSION: The Dykens' and Impulsivity questionnaires can help diagnose severe hyperphagia with/without food impulsivity in children with early-onset obesity, regardless of disease origin. Their systematic use can allow more targeted management of food access control in clinical practice and monitor the evolution of eating behavior in the case of innovative therapeutic targeting hyperphagia.

Management of Severe Malnutrition Post-bariatric Surgery Using Artificial Nutrition.

BACKGROUND: Bariatric surgery (BS) results in major and sustained weight loss and improves comorbidities in patients with obesity but can also lead to malnutrition, especially through severe malabsorption and/or surgical complications. Little is known about the efficacy of artificial nutrition (AN) in this setting. METHODS: In this case series, we describe data from consecutive severely malnourished patients after BS (resectional and non-resectional), managed by AN at our hospital unit over a 4-year period. RESULTS: Between January 2018 and June 2022, 18 patients (mean ± SD age 42.2 ± 10.4 years, 94% women) required AN following BS complications. At the time of AN initiation, more than half of the patients (53%) had multiple revisional surgeries (up to four). Mean BMI was 49.7 ± 11.3 kg/m2 before BS and 29.6 ± 9.6 kg/m2 when AN was initiated. Most patients (n=16, 90%) received enteral nutrition. AN management resulted in weight regain (+4.7kg ± 8.0, p=0.034), increased serum albumin (+28%, p=0.02), pre-albumin (+88%, p=0.002), and handgrip strength (+38%, p=0.078). No major AN complication nor death was observed. Median total AN duration was 4.5 months [1-12]. During follow-up, the cumulative duration of hospitalization was 33 days [4-88] with a median of 2.5 hospitalizations [1-8] per patient. CONCLUSION: Malnutrition can occur after any BS procedure, and AN when required in this setting appears safe and effective on nutritional parameters. It is important to recognize the potential risk factors for malnutrition, which include excessive weight loss resulting from surgical complications, eating disorders, multiple revisional BS, and pregnancy.