Alterations in fatty acid metabolism in response to obesity surgery combined with dietary counseling

Effect of FADS1 SNPs rs174546, rs174547 and rs174550 on blood fatty acid profiles and plasma free oxylipins

Introduction

Previous studies have indicated that activity of fatty acid desaturase 1 (FADS1), is involved in cardiometabolic risk. Recent experimental data have shown that FADS1 knockdown can promote lipid accumulation and lipid droplet formation in liver cells. In this study, we aimed to characterize whether different FADS1 genotypes affect liver fat content, essential fatty acid content and free oxylipin mediators in the blood.

Methods

We analyzed the impact of FADS1 single-nucleotide polymorphisms (SNPs) rs174546, rs174547, and rs174550 on blood fatty acids and free oxylipins in a cohort of 85 patients from an academic metabolic medicine outpatient center. Patients were grouped based on their genotype into the homozygous major (derived) allele group, the heterozygous allele group, and the homozygous minor (ancestral) allele group. Omega-3 polyunsaturated fatty acids (n-3 PUFA) and omega-6 polyunsaturated fatty acids (n-6 PUFA) in the blood cell and plasma samples were analyzed by gas chromatography. Free Oxylipins in plasma samples were analyzed using HPLC-MS/MS. Liver fat content and fibrosis were evaluated using Fibroscan technology.

Results

Patients with the homozygous ancestral (minor) FADS1 genotype exhibited significantly lower blood levels of the n-6 PUFA arachidonic acid (AA), but no significant differences in the n-3 PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). There were no significant differences in liver fat content or arachidonic acid-derived lipid mediators, such as thromboxane B2 (TXB2), although there was a trend toward lower levels in the homozygous ancestral genotype group.

Discussion

Our findings suggest that FADS1 genotypes influence the blood levels of n-6 PUFAs, while not significantly affecting the n-3 PUFAs EPA and DHA. The lack of significant differences in liver fat content and arachidonic acid-derived lipid mediators suggests that the genotype-related variations in fatty acid levels may not directly translate to differences in liver fat or inflammatory lipid mediators in this cohort. However, the trend towards lower levels of certain lipid mediators in the homozygous ancestral genotype group warrants further investigation to elucidate the underlying mechanisms of different FADS1 genotypes and potential implications for cardiometabolic risk.

Anti-obesity effect of Lythri herba water extracts in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Lythrum salicaria L., also called purple loosestrife, has traditionally been used as a medicinal plant to treat internal dysfunction, such as gastrointestinal disorders or hemorrhages. It contains numerous phytochemical compounds, including orientin, and has been reported to have anti-diarrheal, anti-inflammatory, antioxidant, and antimicrobial properties.

AIM OF THE STUDY

The effects of Lythrum salicaria L. on obesity have not been explored. Therefore, we investigated the anti-obesity effects of Lythri Herba, the aerial part of this plant, in vitro and in vivo.

MATERIALS AND METHODS

Using distilled water, Lythri Herba water extracts (LHWE) were prepared by extracting Lythri Herba at 100°Ϲ. The contents of orientin in LHWE were identified using High Performance Liquid Chromatography (HPLC) analysis. To evaluate the anti-obesity effect of LHWE, 3T3-L1 adipocytes and a high-fat diet (HFD)-fed mice were used. Oil-red O staining was performed to examine the anti-adipogenic effects of LHWE in vitro. The histological changes in epididymal white adipose tissue (epiWAT) by LHWE were examined using hematoxylin and eosin staining. Serum leptin levels were measured by enzyme-linked immunosorbent assay. Specific quantification kits measured total cholesterol and triglyceride levels in the serum. The relative fold induction of protein and mRNA was determined using western blot and Quantitative real-time Polymerase Chain Reaction analysis, respectively.

RESULTS

HPLC analysis demonstrated the presence of orientin in LHWE. LHWE treatment markedly reduced lipid accumulation in differentiated 3T3-L1 adipocytes. LHWE administration also conferred resistance to HFD-induced weight gain in mice and reduced epiWAT mass. Mechanistically, LHWE significantly decreased lipogenesis by downregulating lipoprotein lipase (LPL), glucose-6-phosphate dehydrogenase, ATP-citrate lyase, fatty acid synthase, stearoyl-CoA desaturase 1, sterol regulatory element binding transcription factor 1, and carbohydrate response element binding protein expression and increased the expression of genes involved in fatty acid oxidation (FAO), peroxisome proliferator-activated receptor α and carnitine palmitoyltransferase 1 in 3T3-L1 adipocytes and epiWAT. Furthermore, LHWE significantly up-regulated the phosphorylation of AMP-activated protein kinase in 3T3-L1 adipocytes and epiWAT.

CONCLUSION

LHWE decreases white adipogenesis in vitro and HFD-induced weight gain in vivo, which is associated with reduced lipogenesis and enhanced FAO.

The effect of weight loss on whole-body and tissue-specific insulin sensitivity and hepatic lipid content and composition: SWEET substudy

OBJECTIVE

This study (1) investigated the effect of weight loss on whole-body and tissue-specific insulin sensitivity and on intrahepatic lipid (IHL) content and composition and (2) investigated the association between weight-loss-induced changes in insulin sensitivity and IHL content in individuals with overweight or obesity.

METHODS

In this secondary analysis of the European SWEET project, 50 adults (age 18-65 years) with overweight or obesity (BMI ≥ 25 kg/m² ) followed a low-energy diet (LED) for 2 months. At baseline and after the LED, body composition (dual-energy x-ray absorptiometry), IHL content and composition (proton magnetic resonance spectroscopy), whole-body insulin sensitivity (Matsuda index), muscle insulin sensitivity index (MISI), and hepatic insulin resistance index (HIRI) were determined (7-point oral glucose tolerance test).

RESULTS

The LED reduced body weight (p < 0.001). This was accompanied by increased Matsuda index and reduced HIRI (both p < 0.001) but no change in MISI (p = 0.260). Weight loss decreased IHL content (mean [SEM], 3.9% [0.7%] vs. 1.6% [0.5%], p < 0.001) and the hepatic saturated fatty acid fraction (41.0% [1.5%] vs. 36.6% [1.9%], p = 0.039). The reduced IHL content was associated with an improvement in HIRI (r = 0.402, p = 0.025).

CONCLUSIONS

Weight loss decreased IHL content and the hepatic saturated fatty acid fraction. The decrease in IHL content was associated with weight-loss-induced improvement in hepatic insulin sensitivity in individuals with overweight or obesity.

Differential effects of bariatric surgery and lifestyle interventions on plasma levels of Lp(a) and fatty acids

BACKGROUND

Limited evidence suggests that surgical and non-surgical obesity treatment differentially influence plasma Lipoprotein (a) [Lp(a)] levels. Further, a novel association between plasma arachidonic acid and Lp(a) has recently been shown, suggesting that fatty acids are a possible target to influence Lp(a). Here, the effects of bariatric surgery and lifestyle interventions on plasma levels of Lp(a) were compared, and it was examined whether the effects were mediated by changes in plasma fatty acid (FA) levels.

METHODS

The study includes two independent trials of patients with overweight or obesity. Trial 1: Two-armed intervention study including 82 patients who underwent a 7-week low energy diet (LED), followed by Roux-en-Y gastric bypass and 52-week follow-up (surgery-group), and 77 patients who underwent a 59-week energy restricted diet- and exercise-program (lifestyle-group). Trial 2: A clinical study including 134 patients who underwent a 20-week very-LED/LED (lifestyle-cohort).

RESULTS

In the surgery-group, Lp(a) levels [median (interquartile range)] tended to increase in the pre-surgical LED-phase [17(7-68)-21(7-81)nmol/L, P = 0.05], but decreased by 48% after surgery [21(7-81)-11(7-56)nmol/L, P < 0.001]. In the lifestyle-group and lifestyle-cohort, Lp(a) increased by 36%[14(7-77)-19(7-94)nmol/L, P < 0.001] and 14%[50(14-160)-57(19-208)nmol/L, P < 0.001], respectively. Changes in Lp(a) were independent of weight loss. Plasma levels of total saturated FAs remained unchanged after surgery, but decreased after lifestyle interventions. Arachidonic acid and total n-3 FAs decreased after surgery, but increased after lifestyle interventions. Plasma FAs did not mediate the effects on Lp(a).

CONCLUSION

Bariatric surgery reduced, whereas lifestyle interventions increased plasma Lp(a), independent of weight loss. The interventions differentially influenced changes in plasma FAs, but these changes did not mediate changes in Lp(a).

TRIAL REGISTRATION

Trial 1: Clinicaltrials.gov NCT00626964. Trial 2: Netherlands Trial Register NL2140 (NTR2264).

A multi-marker integrative analysis reveals benefits and risks of bariatric surgery

Bariatric surgery (BS) is an effective intervention for severe obesity and associated comorbidities. Although several studies have addressed the clinical and metabolic effects of BS, an integrative analysis of the complex body response to surgery is still lacking. We conducted a longitudinal data study with 36 patients with severe obesity who were tested before, 6 and 12 months after restrictive BS for more than one hundred blood biomarkers, including clinical, oxidative stress and metabolic markers, peptide mediators and red blood cell membrane lipids. By using a synthetic data-driven modeling based on principal component and correlation analyses, we provided evidence that, besides the early, well-known glucose metabolism- and weight loss-associated beneficial effects of BS, a tardive, weight-independent increase of the hepatic cholesterol metabolism occurs that is associated with potentially detrimental inflammatory and metabolic effects. Canonical correlation analysis indicated that oxidative stress is the most predictive feature of the BS-induced changes of both glucose and lipids metabolism. Our results show the power of multi-level correlation analysis to uncover the network of biological pathways affected by BS. This approach highlighted potential health risks of restrictive BS that are disregarded with the current practice to use weight loss as surrogate of BS success.

Changes in the expression of meteorin-like (METRNL), irisin (FNDC5), and uncoupling proteins (UCPs) after bariatric surgery

OBJECTIVE

Bariatric surgery is currently the most effective treatment for severe obesity. This study aims to investigate the changes in expression levels of meteorin-like protein (METRNL), irisin (FNDC5), and uncoupling proteins (UCP) 1/2/3 following bariatric surgery to understand their involvement in enhancing metabolism after surgery.

METHOD

A total of 40 participants were enrolled in this interventional study, 20 with obesity BMI ≥ 35 kg/m² and 20 with BMI ≤ 25 kg/m² . Bariatric surgery (laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass) was performed. The levels of various molecules of interest were analyzed before and after surgery.

RESULTS

Gene expression analysis revealed significantly higher levels of METRNL, UCP1, and UCP3 in individuals with obesity when compared with healthy individuals before surgery (p < 0.05). Gene expression levels of METRNL and UCP2 showed a significant increase after bariatric surgery (p < 0.05). METRNL plasma level was significantly higher in individuals with obesity before surgery (mean [SEM], 55,222.6 [1,421.1] pg/mL, p = 0.0319), as well as at 6 and 12 months (57,537.3 [1,303.9] pg/mL, p = 0.0005; 59,334.9 [1,214.3] pg/mL, p < 0.0001) after surgery.

CONCLUSION

The changes in the levels of various molecules of interest support their possible involvement in the inflammatory and thermogenic responses following bariatric surgery.

Longitudinal Changes in the Fatty Acid Profile in Patients with Head and Neck Cancer: Associations with Treatment and Inflammatory Response

Simple Summary

Cancer-associated malnutrition affects nutrient metabolism, including the metabolism of lipids. Toxicities associated with the treatment for head and neck cancer (HNC) may contribute to malnutrition through impaired oral intake and inflammation. Studies on lipid metabolism in patients with HNC are very limited. The anti-inflammatory effect of some fatty acids (FAs) is already proven in other cancers but the results of these studies in HNC are not consistent. This prospective study of 174 patients with HNC contributes to our knowledge of alterations in lipid metabolism following treatment for HNC and serves as basis for future research.

Abstract

Studies on fatty acids (FAs) in patients with head and neck cancer (HNC) are limited. We aimed to investigate the longitudinal changes of circulating FAs in patients with HNC and to examine potential correlations of FA changes with treatment. The secondary aims were to investigate correlations of FAs with cytokines and patient-related factors, and if any FAs correlated with disease recurrence or death. A total of 174 patients with HNC were included before treatment and followed-up at three time points after the start of the treatment through blood sampling and body weight measurements. Serum FA profiling was assessed by gas chromatography. The total follow-up time was 3 years. The levels of almost all FAs changed from baseline to 7 weeks. The change in FA 14:0 was associated with treatment and the change in 18:3n-6 was associated with the patients’ pre-treatment BMI. FAs 14:0 and 18:0 were correlated with weight changes from baseline to 7 weeks. IL-6 was correlated with three FAs at 7 weeks and with two FAs at 1 year. Patients with higher levels 20:5n-3 at 3 months had a higher risk of all-cause death within 3 years (HR 2.75, 95% CI 1.22–6.21). Treatment, inflammation, and weight loss contributed in a complex manner to the altered FA profile in the studied cohort. The association between IL-6 and FAs in patients with HNC is in line with earlier studies and suggests the opportunity for regulating inflammation in HNC patients through modulation of FAs.

Fatty Acid Metabolism and Derived-Mediators Distinctive of PPAR-α Activation in Obese Subjects Post Bariatric Surgery

Bariatric surger (BS) is characterized by lipid metabolic changes as a response to the massive release of non-esterified fatty acids (NEFA) from adipose depots. The study aimed at evaluating changes in polyunsaturated fatty acids (PUFA) metabolism and biosynthesis of the lipid mediators N-acylethanolamines (NAE), as indices of nuclear peroxisome proliferator-activated receptor (PPAR)-α activation. The observational study was performed on 35 subjects (27 female, 8 male) with obesity, undergoing bariatric surgery. We assessed plasma FA and NAE profiles by LC-MS/MS, clinical parameters and anthropometric measures before and 1 and 6 months after bariatric surgery. One month after bariatric surgery, as body weight and clinical parameters improved significantly, we found higher plasma levels of N-oleoylethanolamine, arachidonic and a 22:6-n3/20:5-n3 ratio as evidence of PPAR-α activation. These changes corresponded to higher circulating levels of NEFA and a steep reduction of the fat mass. After 6 months 22:6-n3/20:5-n3 remained elevated and fat mass was further reduced. Our data suggest that the massive release of NEFA from adipose tissue at 1-Post, possibly by inducing PPAR-α, may enhance FA metabolism contributing to fat depot reduction and improved metabolic parameters in the early stage. However, PUFA metabolic changes favor n6 PUFA biosynthesis, requiring a nutritional strategy aimed at reducing the n6/n3 PUFA ratio.

Impact of Fatty Acids on Obesity-Associated Diseases and Radical Weight Reduction

Purpose

Fatty acids (FA), particularly polyunsaturated (PUFA) ones, are involved in the regulation of glycemic control, lipid metabolism, and inflammation. The aim of the study was to assess patient FA profile in relation to obesity, lipid and carbohydrate metabolism disturbances, and weight loss.

Materials and Methods

The studied group consisted of 51 patients with extreme obesity, 23 of whom achieved radical weight reduction within 1 year after a laparoscopic sleeve gastrectomy (LSG). FA levels were determined using gas chromatography with flame ionization detection.

Results

Patients with extreme obesity and higher serum PUFA content have lower serum levels of SFA and MUFA (especially myristic, palmitic, lignoceric acids and palmitoleic, oleic acids), as well as lower triglyceride and higher HDL-cholesterol concentrations and it was not influenced by CEPT Taq1B variant. At baseline, the fatty acid profile of patients with type II diabetes differ from patients with dyslipidemia. In patients who had lost weight, significantly lower levels of selected saturated FA and major trans-fatty acid, elaidic, were found. Moreover, the proportion of PUFA was increased.

Conclusion

In extreme obesity, higher PUFA exert their favorable effects on serum lipids. Significant weight reduction after the bariatric surgery is associated with beneficial changes in the fatty acid profile.

Graphical Abstract

The importance of age in compositional and functional profiling of the human intestinal microbiome

The intestinal microbiome plays a central role in human health and disease. While its composition is relatively stable throughout adulthood, the microbial balance starts to decrease in later life stages. Thus, in order to maintain a good quality of life, including the prevention of age-associated diseases in the elderly, it is important to understand the dynamics of the intestinal microbiome. In this study, stool samples of 278 participants were sequenced by whole metagenome shotgun sequencing and their taxonomic and functional profiles characterized. The two age groups, below65 and above65, could be separated based on taxonomic and associated functional features using Multivariate Association of Linear Models. In a second approach, through machine learning, biomarkers connecting the intestinal microbiome with age were identified. These results reflect the importance to select age-matched study groups for unbiased metagenomic data analysis and the possibility to generate robust data by applying independent algorithms for data analysis. Furthermore, since the intestinal microbiome can be modulated by antibiotics and probiotics, the data of this study may have implications on preventive strategies of age-associated degradation processes and diseases by microbiome-altering interventions.

Depletion of Omega-3 Fatty Acids in RBCs and Changes of Inflammation Markers in Patients With Morbid Obesity Undergoing Gastric Bypass

BACKGROUND

Bariatric surgery is considered the most effective treatment for severe obesity. Despite this wide success, bariatric surgery is associated with increased risks of nutritional deficiencies.

OBJECTIVES

To examine whether Roux-en-Y-gastric bypass (RYGB) alters essential fatty acid (FA) status and inflammation markers.

METHODS

Subjects with obesity (n = 28; BMI > 40 kg/m2; mean age 48 years) were studied before and 1 year after RYGB. We collected blood samples before and 12 months after RYGB, and analyzed FA in RBCs and peripheral blood mononuclear cells (PBMC), and measured inflammation parameters in plasma. The proportion of total n-3 FAs was the primary outcome, while parameters related to other FAs and inflammation factors were the secondary parameters. In addition, PBMCs from 15 of the participants were cultured alone or with 100 and 200 μM DHA, and the production of IL-6, IL-1β, PGE2, and prostaglandin F2-alpha (PGF2α) was assayed after endotoxin (LPS) stimulation.

RESULTS

RYGB induced a significant reduction of BMI (-30%) and improvement of insulin resistance (-49%). While the proportion of arachidonic acid was 15% higher after RYGB, the proportions of total and individual n-3 FAs were 50%-75% lower (P < 0.01). Consequently, the RBC omega-3 index and n-3:n-6 fatty acid ratio were 45% and 50% lower after surgery, respectively. In isolated PBMCs, LPS induced the production of IL-6, IL-1β, PGE2, and PGF2α in both pre- and post-RYGB cells, but the effects were 34%-65% higher (P < 0.05) after RYGB. This effect was abrogated by DHA supplementation.

CONCLUSIONS

This study presents evidence that RBC and PBMC n-3 FAs are severely reduced in patients with obesity after RYGB. DHA supplementation in PBMC moderates the production of inflammation markers, suggesting that n-3 FA supplementation would merit a trial in bariatric patients.

Early pregnancy plasma fatty acid profiles of women later diagnosed with gestational diabetes

INTRODUCTION

Fatty acid (FA) concentrations have previously been associated with gestational diabetes mellitus (GDM). However, few studies on GDM have examined FA profiles in early pregnancy or before diagnosis. This study aimed to compare early pregnancy plasma FA profiles of women with and without GDM diagnoses as well as their reported dietary consumption.

RESEARCH DESIGN AND METHODS

The subjects comprised 853 women from the prospective study: Pregnant Women in Iceland II (PREWICE II), attending their 11-14 weeks ultrasound appointment in 2017-2018. During the visit, blood samples were collected for plasma FA analysis, and dietary habits were assessed using a short food frequency questionnaire. Information on GDM diagnoses was then later extracted from medical records. Differences in FA profile between GDM cases and non-cases were evaluated using the Mann-Whitney U test.

RESULTS

GDM was diagnosed in 127 women (14.9%). Concentrations of saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids (PUFA) n-6, PUFA n-3 and total FA were higher in the women who later developed GDM compared with those who did not (p≤0.05). The medians for total FA were 2898 μg/mL for the women with GDM and 2681 μg/mL for those without GDM. Mean adjusted difference for total FA between the groups was 133 μg/mL (95% CI 33 to 233). Similar results were observed in prepregnancy normal-weight women and overweight women/women with obesity. Overall diet quality in early pregnancy appeared to be lower among the women later diagnosed with GDM.

CONCLUSION

We found that plasma FA profiles in early pregnancy were different for women later diagnosed with GDM compared with those who were not, independent of the women's body mass index.

The Effects of One-Anastomosis Gastric Bypass on Fatty Acids in the Serum of Patients with Morbid Obesity

Purpose

Obesity is associated with alterations in serum fatty acid profiles. One-anastomosis gastric bypass is a type of bariatric surgery used in the treatment of morbid obesity. The aim of this study was to establish if, between 6 and 9 months after this procedure, the fatty acid composition in the serum of patients normalizes to values similar to the healthy, lean population.

Materials/Methods

The study included 46 patients that underwent surgical treatment for obesity with one-anastomosis gastric bypass. The serum fatty acid composition was determined using gas chromatography-mass spectrometry. Principal component analysis was conducted to detect the differences between fatty acid profiles in patients pre- and post-surgery, and in 29 control nonobese subjects.

Results

Patients with morbid obesity were characterized by lowered levels of beneficial odd- and branched-chain fatty acids and polyunsaturated fatty acids. While the odd- and branched-chain fatty acid amounts normalized 6–9 months after bariatric treatment, the polyunsaturated fatty acid levels did not. Moreover, the total fatty acid profiles of patients pre- and post-bariatric surgery were still markedly different than those of lean, healthy controls.

Conclusion

Following one-anastomosis gastric bypass, there are some beneficial changes in serum fatty acids in treated patients, possibly due to weight loss and dietary regimen changes. However, they may be insufficient to restore the proper levels of other fatty acids, which may need to be additionally supplemented.

Graphical abstract

Al-Dirbashi O, Alkaabi J. Metabolomic Profiling of Lipids and Fatty Acids: 3 Years Postoperative Laparoscopic Sleeve Gastrectomy

Visceral obesity is common in the United Arab Emirates and worldwide. Although laparoscopic sleeve gastrectomy (LSG) leads to effective and sustainable weight loss, its long-term beneficial impact on other risk factors, including blood lipid and fatty acid (FA) profiles, remains unknown. These two profiles were assessed in patients 3 years after undergoing LSG and in LSG candidates (controls). Lipid profiles were measured using the Cobas e411 modular analyzer, and 35 FAs were identified. The age and body mass index were 36.55 ± 8.65 years and 31.49 ± 6.43 kg/m2 in the LSG group and 35.44 ± 9.51 years and 32.29 ± 5.38 kg/m2 in the control group, respectively. The overall lipid profile was more favorable in the LSG group than in the control group. Total saturated, monounsaturated, and polyunsaturated FAs were similar between the groups, but total medium-chain FAs were more abundant in the LSG group. In endogenous FA synthesis, the estimated activity of C16Δ9 desaturase and Δ5 desaturase decreased, whereas that of elongase increased in the LSG group compared with that in the control group. The benefits of LSG on blood lipid and FA profiles in patients with 3-year LSG may be limited. Hence, lifestyle interventions combined with a long-term and strict regular follow-up regime may be warranted for patients undergoing LSG.

Bioavailability and conversion of plant based sources of omega-3 fatty acids - a scoping review to update supplementation options for vegetarians and vegans

Omega-3 (n-3) fatty acids offer a plethora of health benefits with the majority of evidence showing beneficial effects from marine sources of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Emerging research examines the effects of n-3 dietary intakes on blood markers of vegetarians and vegans, but official guidance for plant based marine alternatives is yet to reach consensus. This scoping review provides an overview of trials investigating bioavailability of plant n-3 oils including EPA and DHA conversion. Searches of MEDLINE, PubMed, CINAHL and clinical trial registers identified randomized controlled trials from January 2010 to September 2020. The 'Omega-3 index' (EPA + DHA (O3I)), was used to compare n-3 status, metabolic conversion and bioavailability. Two reviewers independently screened articles and extracted data on outcomes. From 639 identified articles, screening and eligibility checks gave 13 articles. High dose flaxseed or echium seed oil supplements, provided no increases to O3I and some studies showed reductions. However, microalgal oil supplementation increased O3I levels for all studies. Findings indicate preliminary advice for vegetarians and vegans is regular consumption of preformed EPA and DHA supplements may help maintain optimal O3I. Further studies should establish optimum EPA and DHA ratios and dosages in vegetarian and vegan populations.

The effect of a duodenal-jejunal bypass liner on lipid profile and blood concentrations of long chain polyunsaturated fatty acids

BACKGROUND & AIMS

Duodenal-jejunal bypass liners (DJBLs) prevent absorption in the proximal small intestine, the site of fatty acid absorption. We sought to investigate the effects of a DJBL on blood concentrations of essential fatty acids (EFAs) and bioactive polyunsaturated fatty acids (PUFAs).

METHODS

Sub-study of a multicentre, randomised, controlled trial with two treatment groups. Patients aged 18-65 years with type-2 diabetes mellitus and body mass index 30-50 kg/m² were randomised to receive a DJBL for 12 months or best medical therapy, diet and exercise. Whole plasma PUFA concentrations were determined at baseline, 10 days, 6 and 11.5 months; data were available for n = 70 patients per group.

RESULTS

Weight loss was significantly greater in the DJBL group compared to controls after 11.5 months: total body weight loss 11.3 ± 5.3% versus 6.0 ± 5.7% (mean difference [95% CI] = 5.27% [3.75, 6.80], p < 0.001). Absolute concentrations of both EFAs, linoleic acid and α-linolenic acid, and their bioactive derivatives, arachidonic acid, eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid, were significantly lower in the DJBL group than in the control group at 6 and 11.5 months follow-up. Total serum cholesterol, LDL-cholesterol and HDL-cholesterol were also significantly lower in the DJBL group.

CONCLUSION

One year of DJBL therapy is associated with superior weight loss and greater reductions in total serum cholesterol and LDL-cholesterol, but also depletion of EFAs and their longer chain derivatives. DJBL therapy may need to be offset by maintaining an adequate dietary intake of PUFAs or by supplementation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02459561.

Improvement of nutritional intake for the low-income urban dwellers with hypertension in Malaysia

Objective:

To ascertain the effect of dietary practice modification and a peer-support home blood pressure monitoring program on the nutritional intake (macronutrients and micronutrients), blood pressure and biochemical profiles of hypertension patients in a low-income community setting.

Methods:

This is a pre- and post-measurement intervention study conducted in low-income community housing projects in Kuala Lumpur, Malaysia. A total of 90 participants aged 18 years and above with hypertension received intervention. The participants were divided into small groups and received instructions on the use of home blood pressure measurement. They also attended a series of talks on dietary intake modification and exercise demonstration for the first six months (active phase). In another 6 months (maintenance phase), they received only pamphlet and SMS reminders. Their anthropometry, blood pressure, dietary, and biochemical parameter changes were measured at baseline, 6 months, and 12 months of intervention.

Results:

Macronutrients and micronutrients showed a significant improvement at the end of 12-month dietary intervention. The energy, carbohydrate, protein, total fat, sodium, and potassium are showing significant reduction from baseline to end of the 12-month intervention. There is no significant reduction in blood pressure. Fasting blood glucose, renal sodium, triglyceride, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol showed a significant improvement, after controlling for age and reported physical activity.

Conclusion:

The intervention improved the nutritional intake and biochemical profiles of the low-income urban population with hypertension. This promising result should be replicated in a larger scale study.

Intramuscular accumulation of pentadecanoic acid activates AKT1 to phosphorylate NCOR1 and triggers FOXM1-mediated apoptosis in the pathogenesis of sarcopenia

Sarcopenia is an age-associated disorder that results in skeletal muscle loss. Apoptosis and inflammation are the two major contributors to sarcopenia. Emerging evidence has shown that long-chain fatty acids (LCFAs) are implicated in the muscles of sarcopenic animal models. However, it is unknown whether LCFAs are correlated with apoptosis or inflammation in the pathogenesis of sarcopenia. Herein, we found that pentadecanoic acid (PDA), a C15 LCFA, was significantly accumulated in human sarcopenic muscles. In vitro PDA treatment could dose-dependently induce the expression of the transcription factor FOXM1 (forkhead box M1) and several proapoptotic genes, such as PUMA (p53-upregulated modulator of apoptosis), BAX (B-cell/lymphoma 2-associated X) and APAF1 (apoptotic peptidase activating factor 1), thereby causing apoptosis. Mechanically, PDA activated AKT1 (AKT serine/threonine kinase 1) to phosphorylate NCOR1 (nuclear receptor corepressor 1). The phosphorylated NCOR1 disassociated from the NCOR1-FOXM1 transcriptional complex and could not repress FOXM1-mediated transcription, leading to the induction of PUMA. The activated PUMA further triggered downstream apoptotic signaling, including activation of the BAX, APAF1 and caspase cascades, leading to the occurrence of apoptosis. Alkaline phosphatase or knockdown of AKT1 in vitro reversed the FOXM1-mediated apoptotic signaling. Collectively, our results provide new evidence that LCFAs are involved in the pathogenesis of sarcopenia by activating apoptotic signaling. Attempts to decrease the intake of PDA-containing foods or blocking AKT1 may improve the symptoms of sarcopenia.

Bariatric Surgery: Remission of Inflammation, Cardiometabolic Benefits, and Common Adverse Effects

Obesity is associated with increased mortality as a result of several comorbidities which occur in tandem with the obese state. Chronic inflammation is well documented in obesity, and evidence from numerous studies support the notion that the increased inflammation in individuals with obesity accentuates the comorbidities seen in this condition. The remission of comorbidities such as metabolic, cardiovascular, and neurological complications occurs following bariatric procedures. Bariatric surgery significantly reduces mortality and results in remarkable weight loss and reversal in several obesity-related comorbidities. There is indisputable evidence that the resolution of inflammation that occurs after bariatric surgery mitigates some of these comorbidities. With the increasing use of bariatric surgery for the treatment of severe obesity, it is pivotal to elucidate the underlying mechanisms responsible for the notable improvements seen after the procedure. This review summarizes underlying mechanisms responsible for the remission of obesity-related abnormalities and discusses the common adverse effects of bariatric surgery. Well-stratified, large-scale studies are still needed for a proper evaluation of these underlying mechanisms.

Bariatric surgery and kidney disease outcomes in severely obese youth

Bariatric surgery, an emerging treatment for severely obese youth with and without T2D, provides marked improvement in insulin resistance, beta-cell function, and central adiposity. Further, preliminary data suggest that bariatric surgery also results in significant improvement in markers of obesity-related nephropathy and DKD, beyond that which can be achieved with current medical interventions. Yet, the mechanisms whereby bariatric surgery attenuates kidney disease remain unclear. This review summarizes the data on the effects of bariatric surgery on obesity-related nephropathy and DKD in youth with and without T2D, in addition to potential mechanisms underlying the nephroprotective effects of weight loss surgery and how these may differ in Roux-en-Y gastric bypass vs. vertical sleeve gastrectomy. Finally, we discuss potential future non-surgical therapies to mitigate kidney disease.

Short-Term Effect of One-Anastomosis Gastric Bypass on Essential Fatty Acids in the Serum of Obese Patients

One-anastomosis gastric bypass is a promising type of bariatric surgery, but it may lead to a deficiency in important nutrients, such as fatty acids. The short-term effects of one-anastomosis gastric bypass on serum fatty acids have not been studied thus far. Therefore, the aim of this study was to determine the effect of one-anastomosis gastric bypass on serum fatty acid composition two weeks after surgery. This study included 38 patients who underwent one-anastomosis gastric bypass as surgical treatment for morbid obesity. Serum fatty acid composition was analyzed before and two weeks after surgery using gas chromatography–mass spectrometry. We observed a decrease in essential polyunsaturated fatty acids (p < 0.001 for linolenic acid and p < 0.001 for linoleic acid) and odd-chain fatty acids (p = 0.004) in the serum of obese patients shortly after a one-anastomosis gastric bypass. Considering the benefits of the aforementioned fatty acids for human health, the implementation of a fatty-acid-rich diet or the use of supplementation may be recommended for patients immediately after one-anastomosis gastric bypass.

An Ancient Chinese Herbal Decoction Containing Angelicae Sinensis Radix, Astragali Radix, Jujuba Fructus, and Zingiberis Rhizoma Recens Stimulates the Browning Conversion of White Adipocyte in Cultured 3T3-L1 Cells

Background

Abnormal storage of white adipocyte tissue (WAT) is the major factor causing obesity. The promising strategies for obesity treatment are building up the brown adipocyte tissue (BAT) and/or expedite fatty acid catabolism. Traditional Chinese Medicine (TCM) sheds light on preventing obesity. Ginger is one of the most effective herbs for antiobesity by accelerating browning WAT. To fortify the antiobesity effect of ginger, an ancient Chinese herbal decoction composed of four herbs, Angelicae Sinensis Radix (ASR), Astragali Radix (AR), Jujuba Fructus (JF), and Zingiberis Rhizoma Recens (ZRR; ginger), was tested here: this herbal formula was written in AD 1155, named as Danggui Buxue Tang (DBT₁₁₅₅). Therefore, the antiobesity function of this ancient herbal decoction was revealed in vitro by cultured 3T3-L1 cells.

Materials and Method

The lipid accumulation was detected by Oil Red O staining. Furthermore, the underlying working mechanisms of antiobesity functions of DBT₁₁₅₅ were confirmed in 3T3-L1 cells by confocal microscopy, western blot, and RT-PCR.

Results

DBT₁₁₅₅ was able to actuate brown fat-specific gene activations, which included (i) expression of PPARγ, UCP1, and PCG1α and (ii) fatty acid oxidation genes, i.e., CPT1A and HSL. The increase of browning WAT, triggered by DBT₁₁₅₅, was possibly mediated by a Ca²⁺-AMPK signaling pathway, because the application of Ca²⁺ chelator, BAMPTA-AM, reversed the effect.

Conclusion

These findings suggested that the herbal mixture DBT₁₁₅₅ could potentiate the antiobesity functions of ginger, which might have potential therapeutic implications.