Cumulative effect of obesity phenotypes on body weight and body mass index.

BACKGROUND: Obesity originates from an imbalance between energy intake and expenditure. Changes in energy intake components (satiation, postprandial satiety, emotional eating) and energy expenditure have been linked to obesity and are referred to as obesity phenotypes. We aim to study if these obesity phenotypes have a cumulative effect on body weight and body mass index (BMI). SUBJECT/METHODS: This is a cross-sectional study of adult patients with obesity (BMI > 30 kg/m2) who completed the validated tests to measure the obesity phenotypes. A total of 464 were included in this study. INTERVENTIONS/METHODS: We defined higher calories to fullness during an ad libitum meal as abnormal satiation, accelerated time to half gastric emptying with scintigraphy as abnormal postprandial satiety, higher anxiety score on the Hospital Anxiety and Depression Scale as hedonic eating behavior, and decreased percentage of measured resting energy expenditure as abnormal energy expenditure. The primary analysis was done on the number of phenotypes ( ≤ 1 and ≥ 2) with body weight and BMI using an independent t-test. RESULTS: Our cohort included 464 patients (mean [SD] age 42.0 [10.9] years, 79% females, weight 111.2 [22.9] kg, BMI 38.9 [7.0] kg/m2). There were 294 patients who had ≤ 1 phenotype, and 170 patients with ≥ 2 phenotypes with no baseline demographical differences (i.e., age and sex). Having ≥ 2 phenotypes was associated with higher body weight (115 [25] kg vs. 109 [21] kg; p = 0.004), BMI (40 [8] kg/m2 vs. 38 [7] kg/m2; p = 0.02) and waist (118 [15] cm vs. 115 [13] cm; p = 0.04) and hip (129 [14] cm vs. 125 [13] cm; p = 0.01) circumferences compared to ≤ 1 phenotype. CONCLUSION: Obesity phenotypes are associated with an additive effect on the body weight and BMI. Patients who have multiple obesity phenotypes may require a more aggressive approach to enhance weight loss.

Weight loss and cardiovascular disease risk outcomes of semaglutide: a one-year multicentered study.

BACKGROUND/OBJECTIVE: There are limited real-world studies assessing semaglutide weight loss and associated comorbidity and metabolic outcomes over periods ≥ 6 months. We aim to assess weight loss, metabolic, and cardiovascular outcomes of 12 months of semaglutide. SUBJECT/METHODS: We conducted a multicentered retrospective cohort study on semaglutide use. We included patients with a body-mass index (BMI) ≥ 27 kg/m2 who were prescribed weekly semaglutide subcutaneous injections. We excluded patients with bariatric surgeries, taking other anti-obesity medications, and with active malignancy or pregnancy. A total of 1023 patients had semaglutide prescription for obesity. INTERVENTION/METHODS: We assessed weight loss outcomes of subcutaneous semaglutide for 12 months. The primary endpoint was total body weight loss percentage (TBWL%) at 12 months. Secondary endpoints included proportion of patients achieving ≥5%, ≥10%, ≥15%, and ≥20% weight loss, and improvements in metabolic, cardiovascular, and comorbidities after 12 months of follow-up. RESULTS: We included 304 patients (73% female, 93% White, mean age 48.8 [12.4] years, BMI 40.9 [9.6] kg/m2) in the analysis. Patients achieved a TBWL of 13.4 (8.0)% at 12 months (p < 0.001 from baseline). Patients without T2DM achieved a TBWL of 16.9 (6.9)% compared to 9.9 (8.4)% in patients without T2DM at 12 months on the higher doses of semaglutide (p < 0.001 from baseline). In this cohort, 81% achieved ≥5%, 64% achieved ≥10%, 41% achieved ≥15%, and 22% achieved ≥20% TBWL at 12 months. Patients with overweight or obesity experienced significant improvements in metabolic, lipid profile, blood pressure, liver function tests, and cardiovascular disease risk outcomes. CONCLUSIONS: Semaglutide demonstrated notable improvement in obesity, metabolic, and cardiovascular disease risk outcomes in a clinical setting.

The association between previous use of anti-obesity medication and semaglutide weight loss outcomes.

AIMS: To compare weight loss outcomes between patients starting semaglutide who had previously been on another anti-obesity medication (AOM) compared to those who were AOM-naïve. MATERIALS AND METHODS: We performed a retrospective study in patients with overweight or obesity taking semaglutide for weight loss for a duration of 3 to 12 months. Our primary endpoint was assessment of percentage of total body weight loss (TBWL) in patients who started semaglutide as their first AOM (AOM-naïve) compared to those who started semaglutide and had previously taken another AOM (non-AOM-naïve). The secondary outcome was a comparison of the proportions of patients achieving ≥5%, ≥10%, ≥15% and ≥20% TBWL between the groups. Our endpoints were analysed using independent t-tests and ANOVA/ANCOVA for continuous variables and Pearson's test for categorical variables. RESULTS: This study included 305 patients. Outcomes of semaglutide treatment were superior in AOM-naïve patients (n = 231) compared to non-AOM-naïve patients (n = 74) at 3 (6.3% vs. 3.8%), 6 (10.6% vs. 6.7%), 9 (14.0% vs. 9.1%) and 12 months (14.3% vs. 10.6%; p < 0.0001 at 3, 6 and 9 months, and p = 0.01 at 12 months). A greater proportion of patients in the AOM-naïve group achieved a TBWL ≥ 15% (48% vs 21%; p = 0.02) and ≥20% (27% vs 4% p < 0.01) at 12 months. CONCLUSION: The use of semaglutide in patients with previous intake of other AOMs was associated with inferior weight loss outcomes in comparison to patients who were AOM-naïve.

TILETAMINE-ZOLAZEPAM-XYLAZINE ANESTHESIA IN EX SITU BLACK-HANDED SPIDER MONKEYS (ATELES GEOFFROYI SSP.).

Black-handed spider monkeys (Ateles geoffroyi ssp.) are endangered in Mexico. Safe anesthetic protocols are important for in situ and ex situ conservation problems. Such protocols are scarce in the literature; nor have safety and physiologic responses been reported. High doses and volume are a counter side for field immobilizations. We tested an anesthetic protocol with a combination of tiletamine-zolazepam (5 mg/kg) plus xylazine (1 mg/kg) in 14 black-handed spider monkeys under human care from two facilities in Mexico. Physiological parameters such as HR, RR, T, SPO2, systolic arterial pressure (), diastolic arterial pressure (DAP), and median arterial pressure (MAP) were obtained. HR and RR decreased over time, but T increased significantly during the anesthetic time for the whole group; RR and T decreased for juveniles only. Variation between individuals was observed for HR, RR, and DAP. Volume reduction of drugs was achieved compared to previously reported anesthesia protocols. Induction time was fast (6.2 ± 10.4 min) and no tail prehension was seen. Recovery was prolonged (mean and SD). Physiologic parameters remained stable throughout. The protocol proved to be safe for the chemical immobilization of black-handed spider monkeys.

Effect of caloric intake and macronutrient composition on intestinal cholesterol absorption and bile acids in patients with obesity.

Obesity is associated with alterations in cholesterol and bile acid (BA) metabolism. However, the interaction among dietary intake, cholesterol absorption, and BA metabolism in patients with obesity remains unclear. We conducted a 4-wk nutritional intervention nonrandomized clinical trial with three different sequential diets for a week in the following order: regular diet (RD); high calorie, high-fat diet (HCHF), washout period on RD; and low-calorie, low-fat diet (LCLF). We provided participants with meal replacements during HCHF and LCLF diets. A total of 16 participants completed the study [n = 8 normal weight (NW); n = 8 with obesity (OB)]. Overall, there was a significant increase in intestinal cholesterol uptake when changing from RD to HCHF and a reduction in intestinal cholesterol uptake from HCHF to LCLF. When analyzing by BMI groups, these findings were similar in patients with NW (RD to HCHF: P < 0.007; HCHF to LCLF: P = 0.02); however, in patients with obesity, the change in intestinal cholesterol uptake was only observed when changing from RD to HCHF (P = 0.006). There was no correlation between cholesterol absorption and fecal bile acids or other markers of BA metabolism in all patients or the subgroups. Dietary caloric content had a significant effect on cholesterol absorption, however, this effect is blunted in patients with obesity. These data are consistent with the impaired effect of a low-fat diet on cholesterol absorption in obesity.NEW & NOTEWORTHY We show how switching from a regular diet to an HCHF increases cholesterol absorption in patients with normal weight and obesity. The decrease in cholesterol absorption from an HCHF to an LCLF, on the other hand, was only seen in normal-weight controls, underlining the importance of body weight in this regulation. In addition, changes in caloric and fat content had an immediate and direct effect on hepatic bile acid production.

Sex as an independent variable in the measurement of satiation: a retrospective cohort study.

BACKGROUND: Satiation is a key component of food intake regulation as it brings an eating episode to an end. The effect of sex on satiation measurement has not been characterized. OBJECTIVE: To assess the effects of biological variables on satiation. DESIGN: Retrospective cohort study. We included 959 participants (mean age 39 [SD 12] years; 70.7% female, and BMI 33 kg/m2 [8]) who had measurements of satiation with a nutrient-drink test to assess volume to fullness (VTF) and maximum tolerated volume (MTV), and/or an ad libitum meal test to assess calories consumed to fullness (CTF). We performed univariate and multiple regression analyses to estimate the contribution of sex to VTF, MTV, and CTF, compared to other biological variables, such as age, weight, height, BMI, waist-to-hip circumference (W/H), and lean mass percentage (LM%), that are known to affect these parameters. RESULTS: Females had higher BMI, W/H, and LM%. VTF, MTV, and CTF were lower in females: 704 [323] vs. 783 [328] mL, p = 0.001; 1226 [384] vs. 1419 [410] mL, p < 0.001; and 871 [291] vs. 1086 [326] kcal, p < 0.001; respectively. Sex was a strong and independent predictor of VTF, MTF and CTF: parameter estimate [PE] = -80.8, p = 0.006; PE = -124.2, p = 0.0007; and PE = -110, p = 0.001; respectively. CONCLUSIONS: Sex has a strong effect on satiation measured by VTF, MTV, and CTF, even after adjusting for other biological factors known to affect these parameters. Females seem to integrate intra-meal inhibition signals to consume fewer calories unrelated to body size or composition. CLINICAL TRIAL REGISTRATION: None.

Effectiveness of anti-obesity medications approved for long-term use in a multidisciplinary weight management program: a multi-center clinical experience.

BACKGROUND AND AIMS: Randomized clinical trials have proven the efficacy and safety of Food and Drug Administration (FDA) approved anti-obesity medications (AOMs) for long-term use. It is unclear whether these outcomes can be replicated in real-world clinical practice where clinical complexities arise. The aim of this study was to evaluate the effectiveness and side effects of these medications in real-world multidisciplinary clinical practice settings. METHODS: We reviewed the electronic medical records (EMR) of patients with obesity who were prescribed an FDA-approved AOM for long-term use in academic and community multidisciplinary weight loss programs between January 2016 and January 2020. INTERVENTION: We assessed percentage total body weight loss (%TBWL), metabolic outcomes, and side effect profile up to 24 months after AOM initiation. RESULTS: The full cohort consisted of 304 patients (76% women, 95.2% White, median age of 50 years old [IQR, 39-58]). The median follow-up time was 9.1 months [IQR, 4.2-14.1] with a median number of 3 visits [IQR, 2-4]. The most prescribed medication was phentermine/topiramate extended-release (ER) (51%), followed by liraglutide (26.3%), bupropion/naltrexone sustained-release (SR) (16.5%), and lorcaserin (6.2%). %TBWL was 5.0%, 6.8%, 9.3%, 10.3%, and 10.5% at 3, 6, 12, 18, and 24 months. 60.2% of the entire cohort achieved at least 5% TBWL. Overall, phentermine/topiramate-ER had the most robust weight loss response during follow-up, with the highest %TBWL at 12 months of 12.0%. Adverse events were reported in 22.4% of patients. Only 9% of patients discontinued the medication due to side effects. CONCLUSIONS: AOMs resulted in significant long-term weight loss, that was comparable to outcomes previously reported in clinical trials.

Ovine sperm DNA oxidation quantification using an 8-OHdG immunodetection assay.

Our aim was to optimize 8-hydroxy-2'-deoxyguanosine (8-OHdG) immunodetection in order to detect DNA damage caused by oxidative stress that may not be detected by other DNA integrity analysis techniques, especially due to the high compaction of DNA in ruminants. Semen samples from 6 rams were cryopreserved. After thawing, samples were subjected to the DNA oxidation quantification using an 8-OHdG immunodetection assay by flow cytometry. We have evaluated two different incubation times (30 min vs. overnight) at 4°C of the primary antibody (monoclonal anti-8-OHdG antibody). We have also compared the results of this technique with the sperm chromatin structure assay (SCSA® ). The analysis revealed that there were no significant differences (p > .05) between different incubation times. However, overnight incubation seems to cause more non-specific binding of the secondary antibody. Significant differences (p < .05) between subjects and oxidation controls (8 M H2 O2 /800 µM FeSO4 •7H2 O) were evident. We can conclude that the 8-OHdG immunodetection assay for DNA oxidation quantification of ram sperm can be performed subjecting sperm samples to a very high oxidative treatment.

Leptin-Melanocortin pathway variants and gastric emptying in patients with obesity.

BACKGROUND: Accelerated gastric emptying (GE) is a trait seen in obesity. Mutations in the hypothalamic leptin-melanocortin 4 receptor (Leptin-MC4R) pathway have been associated with obesity. We sought to investigate the association of leptin-MC4R pathway variants and GE in patients with obesity. METHODS: This is a cross-sectional study of patients with a history of severe obesity that were genotyped and completed a GE test by scintigraphy. We evaluated the percentage of GE (GE %) at 2 and 4 h between both groups using ANCOVA with weight and sex as covariates. We subdivide patients into carriers based on the location of the identified variants (i.e., upstream or downstream of the Leptin-MC4R pathway) and compared them with noncarriers using ANOVA. Results are presented as mean and standard deviation (± SD). KEY RESULTS: A total of 95 patients; nine carriers (67% females; 39.78 ± 12.33 years; BMI: 49.14 ± 12.96 kg/m2) and 86 noncarriers (87% female; 49.98 ± 13.74 years; BMI: 40.75 ± 6.29 kg/m2) were included. At 2 and 4 h, carriers had a delayed GE when compared noncarriers (p = 0.03 and p = 0.005, respectively). In carriers, when compared upstream carriers vs. downstream carriers vs. noncarriers by location there was a significant difference in GE among groups at 2 h and at 4 h (p = 0.02 and p = 0.01, respectively). CONCLUSIONS & INFERENCES: Carriers of heterozygous variants in the Leptin-MC4R pathway had a delayed GE compared to noncarriers. These findings point the important relationship between the Leptin-MC4R pathway and gastric motility.

Neurohormonal response patterns to hunger, satiation, and postprandial fullness in normal weight, anorexia nervosa, and obesity.

BACKGROUND: Food intake is regulated by homeostatic and hedonic systems that interact in a complex neuro-hormonal network. Dysregulation in energy intake can lead to obesity (OB) or anorexia nervosa (AN). However, little is known about the neurohormonal response patterns to food intake in normal weight (NW), OB, and AN. MATERIAL & METHODS: During an ad libitum nutrient drink (Ensure®) test (NDT), participants underwent three pseudo-continuous arterial spin labeling (pCASL) MRI scans. The first scan was performed before starting the NDT after a > 12 h overnight fast (Hunger), the second after reaching maximal fullness (Satiation), and the third 30-min after satiation (postprandial fullness). We measured blood levels of ghrelin, cholecystokinin (CCK), glucagon-like peptide (GLP-1), and peptide YY (PYY) with every pCASL-MRI scan. Semiquantitative cerebral blood flow (CBF) maps in mL/100 gr brain/min were calculated and normalized (nCBF) with the CBF in the frontoparietal white matter. The hypothalamus (HT), nucleus accumbens [NAc] and dorsal striatum [DS] were selected as regions of interest (ROIs). RESULTS: A total of 53 participants, 7 with AN, 17 with NW (body-mass index [BMI] 18.5-24.9 kg/m2 ), and 29 with OB (BMI ≥30 kg/m2 ) completed the study. The NW group had a progressive decrease in all five ROIs during the three stages of food intake (hunger, satiation, and post-prandial fullness). In contrast, participants with OB showed a minimal change from hunger to postprandial fullness in all five ROIs. The AN group had a sustained nCBF in the HT and DS, from hunger to satiation, with a subsequent decrease in nCBF from satiation to postprandial fullness. All three groups had similar hormonal response patterns with a decrease in ghrelin, an increase in GLP-1 and PYY, and no change in CCK. CONCLUSION: Conditions of regulated (NW) and dysregulated (OB and AN) energy intake are associated with distinctive neurohormonal activity patterns in response to hunger, satiation, and postprandial fullness.

Cattel and Blumgart Anastomosis: Comparison of Pancreatojejunostomy Techniques in Patients with Pancreatic Cancer.

BACKROUND: Pancreaticojejunal anastomosis has a high risk of pancreatic leakage, which several surgical techniques have been described. Our main objective is to determine what is the association of postoperative pancreatic leakage in patients undergoing pancreaticoduodenectomy according to the pancreaticojejunal anastomosis technique used (Cattel vs Blumgart)? MATERIAL AND METHODS: Historical cohort, all cancer patients undergoing pancreaticoduodenectomy were included. From April 2020 to May 2021, Cattel technique was used; from June 2021 to June 2022, Blumgart technique was used. All procedures were performed by a single board-certified surgical oncologist at Oncology Hospital. RESULTS: 24 patients (11 men and 13 women). The first 9 procedures were performed with the Cattel technique, starting from procedure 10, the Blumgart technique was used. No differences were observed regarding the consistency of the pancreas (p=0.28) or the size of the duct (p=0.51) between the two groups. Pancreatic leakage was observed in 100% with the Cattel technique and in 6.7% with the Blumgart technique (p= 0.0001). An amylase value was observed in the left drainage at 6 days > 200 U/L with the Cattel technique and < 200 U/L with Blumgart (p=0.0001). Intraoperative bleeding (Cattel 1200 ml vs. Blumgart 400 ml, p= 0.03) and 90-day mortality (Cattel 33.3% vs. Blumgart 0%, Log-Rank: 0.022) also showed a difference in favor of Blumgart technique. Blumgart technique is a protective factor for the presence of pancreatic leakage (RR 0.06, 95% CI 0.01-0.44, p=0.0001). DISCUSSION: A lower risk of pancreatic leakage was found using the Blumgart technique, compared to the Cattel technique.

Integrin αvß3 Upregulation in Response to Nutrient Stress Promotes Lung Cancer Cell Metabolic Plasticity.

Cancer stem/tumor-initiating cells display stress tolerance and metabolic flexibility to survive in a harsh environment with limited nutrient and oxygen availability. The molecular mechanisms underlying this phenomenon could provide targets to prevent metabolic adaptation and halt cancer progression. Here, we showed in cultured cells and live human surgical biopsies of non-small cell lung cancer that nutrient stress drives the expression of the epithelial cancer stem cell marker integrin αvß3 via upregulation of the ß3 subunit, resulting in a metabolic reprogramming cascade that allows tumor cells to thrive despite a nutrient-limiting environment. Although nutrient deprivation is known to promote acute, yet transient, activation of the stress sensor AMP-activated protein kinase (AMPK), stress-induced αvß3 expression via Src activation unexpectedly led to secondary and sustained AMPK activation. This resulted in the nuclear localization of peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC1α) and upregulation of glutamine metabolism, the tricarboxylic acid cycle, and oxidative phosphorylation. Pharmacological or genetic targeting of this axis prevented lung cancer cells from evading the effects of nutrient stress, thereby blocking tumor initiation in mice following orthotopic implantation of lung cancer cells. These findings reveal a molecular pathway driven by nutrient stress that results in cancer stem cell reprogramming to promote metabolic flexibility and tumor initiation. SIGNIFICANCE: Upregulation of integrin αvß3, a cancer stem cell marker, in response to nutrient stress activates sustained AMPK/PGC1α signaling that induces metabolic reprogramming in lung cancer cells to support their survival. See related commentary by Rainero, p. 1543.

Unraveling the Variability of Human Satiation: Implications for Precision Obesity Management.

Satiation is the physiologic process that regulates meal size and termination, and it is quantified by the calories consumed to reach satiation. Given its role in energy intake, changes in satiation contribute to obesity's pathogenesis. Our study employed a protocolized approach to study the components of food intake regulation including a standardized breakfast, a gastric emptying study, appetite sensation testing, and a satiation measurement by an ad libitummeal test. These studies revealed that satiation is highly variable among individuals, and while baseline characteristics, anthropometrics, body composition and hormones, contribute to this variability, these factors do not fully account for it. To address this gap, we explored the role of a germline polygenic risk score, which demonstrated a robust association with satiation. Furthermore, we developed a machine-learning-assisted gene risk score to predict satiation and leveraged this prediction to anticipate responses to anti-obesity medications. Our findings underscore the significance of satiation, its inherent variability, and the potential of a genetic risk score to forecast it, ultimately allowing us to predict responses to different anti-obesity interventions.

PI3Kγ inhibition circumvents inflammation and vascular leak in SARS-CoV-2 and other infections.

Virulent infectious agents such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and methicillin-resistant Staphylococcus aureus (MRSA) induce tissue damage that recruits neutrophils, monocyte, and macrophages, leading to T cell exhaustion, fibrosis, vascular leak, epithelial cell depletion, and fatal organ damage. Neutrophils, monocytes, and macrophages recruited to pathogen-infected lungs, including SARS-CoV-2-infected lungs, express phosphatidylinositol 3-kinase gamma (PI3Kγ), a signaling protein that coordinates both granulocyte and monocyte trafficking to diseased tissues and immune-suppressive, profibrotic transcription in myeloid cells. PI3Kγ deletion and inhibition with the clinical PI3Kγ inhibitor eganelisib promoted survival in models of infectious diseases, including SARS-CoV-2 and MRSA, by suppressing inflammation, vascular leak, organ damage, and cytokine storm. These results demonstrate essential roles for PI3Kγ in inflammatory lung disease and support the potential use of PI3Kγ inhibitors to suppress inflammation in severe infectious diseases.

Association Between Food Intake and Gastrointestinal Symptoms in Patients With Obesity.

BACKGROUND AND AIMS: Hunger, satiation, postprandial satiety, and hedonic eating constitute key food intake parameters. We aim to study whether these symptoms are associated with gastrointestinal symptoms (GIS) in patients with obesity. METHODS: This is a cross-sectional study of patients with obesity. Patients completed the following validated biomarkers and questionnaires: hunger was measured via visual analog scale (100 mm) following a standard meal, satiation was measured via ad libitum meal (calories to fullness; kcal), postprandial satiety was measured via gastric emptying scintigraphy (T1/2; mins), and hedonic eating was measured via the Hospital Anxiety and Depression Scale questionnaire. Participants completed the abridged Bowel Disease Questionnaire to evaluate their GIS. We calculated the odds ratios (ORs) adjusted for sex, weight, and age between food intake parameters <25th or >75th percentile observed in a prior cohort of 450 participants with obesity and GIS. RESULTS: A total of 274 participants (41 ± 10 [SD] years, 75% females, body mass index 39 ± 8 kg/m2) were included in the analysis. Increased hunger was associated with a lower prevalence of lumpy stools (OR = 0.18, P = .02). Satiation was associated with abdominal pain/discomfort (relieved by defecation [OR = 2.4, P = .02] or associated with change in stool consistency [OR = 2.92, P < .01]), loose/watery stools (OR = 2.09, P = .02), and bloating (OR = 2.49, P < .01). Abnormal postprandial satiety was associated with bloating (OR = 2.26, P < .01) and loose/watery stools (OR = 1.84, P = .04). Hedonic eating was associated with abdominal pain/discomfort with stool frequency change (OR = 2.4, P = .02), >3 bowel movements per day (OR = 1.93, P = .048), bloating (OR = 2.49, P = .01), abdominal pain after meals >1 per month (OR = 4.24, P < .01), and nausea >1 per week (OR = 4.51, P < .01). CONCLUSION: Alterations in hunger, satiation, postprandial satiety, and hedonic eating are associated with GIS in patients with obesity.

Pancreatic cancer cells upregulate LPAR4 in response to isolation stress to promote an ECM-enriched niche and support tumour initiation.

Defining drivers of tumour initiation can provide opportunities to control cancer progression. Here we report that lysophosphatidic acid receptor 4 (LPAR4) becomes transiently upregulated on pancreatic cancer cells exposed to environmental stress or chemotherapy where it promotes stress tolerance, drug resistance, self-renewal and tumour initiation. Pancreatic cancer cells gain LPAR4 expression in response to stress by downregulating a tumour suppressor, miR-139-5p. Even in the absence of exogenous lysophosphatidic acid, LPAR4-expressing tumour cells display an enrichment of extracellular matrix genes that are established drivers of cancer stemness. Mechanistically, upregulation of fibronectin via an LPAR4/AKT/CREB axis is indispensable for LPAR4-induced tumour initiation and stress tolerance. Moreover, ligation of this fibronectin-containing matrix via integrins α5ß1 or αVß3 can transfer stress tolerance to LPAR4-negative cells. Therefore, stress- or drug-induced LPAR4 enhances cell-autonomous production of a fibronectin-rich extracellular matrix, allowing cells to survive 'isolation stress' and compensate for the absence of stromal-derived factors by creating their own tumour-initiating niche.

Cardiovascular Risk and Diseases in Patients With and Without Leptin-Melanocortin Pathway Variants.

OBJECTIVE: To study differences in cardiovascular risk factors and diseases between patients with and without genetic variants in the leptin-melanocortin pathway. METHODS: A cross-sectional study of patients with a history of severe obesity genotyped in June 2019 as participants of the Mayo Clinic Biobank was conducted in March 2022 to assess differences in cardiovascular risk and diseases between carriers of a heterozygous variant in the leptin-melanocortin pathway and noncarriers. Cardiovascular risk factors included hypertension, diabetes, dyslipidemia, and smoking. Cardiovascular disease includes coronary artery disease, peripheral artery disease, and cerebrovascular accidents. Patients with a history of bariatric surgery were excluded. We used logistic regression models to estimate the odds ratio and 95% CI, adjusting for age, body mass index (BMI), and sex. RESULTS: Among a total of 168 carriers (8%; 121 [72%] female; mean [SD] age, 65.1 [14.9] years; BMI, 44.0 [7.4] kg/m2) and 2039 noncarriers (92%; 1446 [71%] female; mean [SD] age, 64.9 [14.4] years; BMI, 42.9 [6.6] kg/m2), carriers had higher prevalence odds of hypertension (odds ratio, 3.26; 95% CI, 2.31 to 4.61; P<.001) and reported higher number of cardiovascular risk factors compared with noncarriers (2.4 [1.1] vs 2.0 [1.1]; P<.001). There were no significant differences in the adjusted odds associated with diabetes, dyslipidemia, smoking, or cardiovascular disease. CONCLUSION: Despite having similar body weight and BMI, carriers of heterozygous variants in the leptin-melanocortin pathway had higher rates of hypertension than noncarriers. These findings point to an association between hypertension and leptin-melanocortin pathway variants.

Type 2 Diabetes Remission in Patients with Heterozygous Variants in the Leptin-Melanocortin Pathway after Roux-en-Y Gastric Bypass: A Matched Case-Control Study.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) is associated with a high rate of type 2 diabetes (T2D) remission. Carriers of heterozygous variants in the leptin-melanocortin pathway (LMP) are more likely to experience weight recurrence after RYGB. Our aim was to investigate if carrier status and associated weight regain affects the rate of T2D remission after RYGB. METHODS: Carriers of LMP variants with a diagnosis of T2D prior to RYGB (N = 16) were matched to non-carriers (N = 32) based on sex, age, and BMI. We assessed for post-operative T2D remission status post-surgery on a yearly basis, for up to 15 years. Our primary endpoint was the proportion of patients achieving T2D remission at 1 year. We conducted a survival analysis for all patients that achieved remission at least at one time-point to evaluate for maintenance of T2D remission by using a log-rank test. RESULTS: Both carriers and non-carriers had similar baseline and procedural characteristics. The proopiomelanocortin gene in the LMP pathway had the most variants (n = 5, 31%). Carriers had a lower total body weight loss percentage at nadir (28.7% ± 6.9) than non-carriers (33.7% ± 8.8, p = 0.04). The proportion of patients achieving T2D remission at 1 year was 68.8% for carriers and 71.9% for non-carriers (p = 1.0). Survival curves for maintenance of first remission were similar for both groups (p = 0.73), with a median survival of 8 years for both carriers and non-carriers. CONCLUSIONS: Despite inferior weight loss outcomes at nadir, carriers had similar T2D remission rates when compared to non-carriers. Weight-independent metabolic benefits of RYGB might contribute to this observation.

Phenotype tailored lifestyle intervention on weight loss and cardiometabolic risk factors in adults with obesity: a single-centre, non-randomised, proof-of-concept study.

Background: Lifestyle interventions for weight loss are currently not individualised to underlying pathophysiology and behavioral traits in obesity. We aim to compare the outcome of a standard lifestyle intervention (SLI) to phenotype-tailored lifestyle interventions (PLI) on weight loss, cardiometabolic risk factors and physiologic variables contributing to obesity. Methods: This 12-week, single-centre non-randomised proof-of-concept clinical trial including men and women aged 18-65 years with a body mass index (BMI) greater than 30 without history of any bariatric procedure, and current use of any medication known to affect weight. Participants lived anywhere in the United States, and underwent in-person testing in Rochester, MN at a teaching hospital. All participants completed in-person phenotype testing at baseline and after 12 weeks. Participants were assigned to their intervention based on their period of enrollment. In the first phase, participants were assigned to SLI with a low-calorie diet (LCD), moderate physical activity, and weekly behavioral therapy sessions. In the second phase, other participants were assigned to PLI according to phenotype: abnormal satiation (time-restricted volumetric LCD); abnormal postprandial satiety (LCD with pre-meal protein supplementation); emotional eating (LCD with intensive behavioral therapy); and abnormal resting energy expenditure (LCD with post-workout protein supplementation and high-intensity interval training). The primary outcome was total body weight loss in kg at 12 weeks using multiple imputation for missing data. Linear models estimated the association of study group allocation and study endpoints adjusting for age, sex, and baseline weight. This study was registered with ClinicalTrials.gov, NCT04073394. Findings: Between July 2020 and August 2021, 211 participants were screened, and 165 were assigned to one of the two treatments in the two phases: 81 SLI (mean [SD] age 42.9 [12] years; 79% women; BMI 38.0 [6.0]) and 84 PLI (age 44.8 [12.2] years; 83% women; BMI 38.7 [6.9]); 146 completed the 12-week programs. The weight loss was -7.4 kg (95%CI, -8.8, -6.0) with PLI vs. -4.3 kg (95%CI, -5.8, -2.7) with SLI (difference, -3.1 kg [95%CI, -5.1 to -1.1]; P = 0.004). No adverse events were reported in any group. Interpretation: Phenotype-tailored lifestyle interventions may result in significant weight loss, but a randomised controlled trial is required to confirm causality. Funding: Mayo Clinic; NIH (K23-DK114460).