Polyunsaturated fatty acids as modulators of fat mass and lean mass in human body composition regulation and cardiometabolic health

Development and application of a sensitive liquid chromatography-tandem mass spectrometry method for the quantitative analysis of 11 free fatty acids in human serum using a derivatisation strategy

A stable isotope dilution-liquid chromatography-tandem mass spectrometry method based on a derivatisation strategy involving an N,N'-carbonylimidazole solution (CDI) with 4-(dimethylamino)-benzenemethanamine was developed for the determination of 11 free fatty acids (FFAs) in human blood samples. Serum samples were subjected to liquid‒liquid extraction and centrifuged, and the supernatant was collected for a two-step derivatisation reaction with a CDI and 4-(dimethylamino)-aniline acetonitrile solution. The derivatised solution was separated on a ACQUITY UPLC HSS T3 column (2.1 × 50 mm, 1.8 µm) column with a mobile phase consisting of water-acetonitrile in gradient elution and then detected by tandem mass spectrometry using electrospray ionisation (ESI) and multiple reaction monitoring (MRM) in positive ion mode and quantified using the isotope internal standard method. The effects of the derivatisation reaction time, temperature and concentration of derivatisation reagents on the response values of the analytes were investigated. The optimal conditions were as follows: 1.0 mg mL-1 CDI acetonitrile solution at 25 °C for 25 min, followed by a reaction with a 1.0 mg mL-1 4-(dimethylamino)-benzenemethanamine acetonitrile solution at 70 °C for 30 min. Under the optimal conditions, the limits of detection (LODs) of the 11 FFAs were in the range of 3.0-14.0 ng mL-1; the limits of quantification (LOQs) were in the range of 8.0-45.0 ng mL-1; and the mean recoveries ranged from 83.4 to 112.8%, with intraday and interday precisions ranging from 0.7 to 9.1% and 3.7-9.5%, respectively. The experimental method is simple in terms of the pretreatment operation, accurate and reliable, and can be applied to the sensitive determination of FFAs in human blood samples.

EPA and DHA promote cell proliferation and enhance activity of the Akt-TOR-S6K anabolic signaling pathway in primary muscle cells of turbot (Scophthalmus maximus L.)

Fish growth and health are predominantly governed by dietary nutrient supply. Although the beneficial effects of omega-3 polyunsaturated fatty acids supplementation have been shown in a number of fish species, the underlying mechanisms are still mostly unknown. In this study, we conducted an investigation into the effects of EPA and DHA on cell proliferation, nutrient sensing signaling, and branched-chain amino acids (BCAA) transporting in primary turbot muscle cells. The findings revealed that EPA and DHA could stimulate cell proliferation, promote protein synthesis and inhibit protein degradation through activation of target of rapamycin (TOR) signaling pathway, a pivotal nutrient-sensing signaling cascade. While downregulating the expression of myogenin and myostatin, EPA and DHA increased the level of myogenic regulatory factors, such as myoD and follistatin. Furthermore, we observed a significant increase in the concentrations of intracellular BCAAs following treatment with EPA or DHA, accompanied by an upregulation of the associated amino acid transporters. Our study providing valuable insights into the mechanisms underlying the growth-promoting effects of omega-3 fatty acids in fish.

The influence of first desaturase subfamily genes on fatty acid synthesis, desiccation tolerance and inter-caste nutrient transfer in the termite Coptotermes formosanus

Desaturase enzymes play an essential role in the biosynthesis of unsaturated fatty acids (UFAs). In this study, we identified seven "first desaturase" subfamily genes (Cfor-desatA1, Cfor-desatA2-a, Cfor-desatA2-b, Cfor-desatB-a, Cfor-desatB-b, Cfor-desatD and Cfor-desatE) from the Formosan subterranean termite Coptotermes formosanus. These desaturases were highly expressed in the cuticle and fat body of C. formosanus. Inhibition of either the Cfor-desatA2-a or Cfor-desatA2-b gene resulted in a significant decrease in the contents of fatty acids (C16:0, C18:0, C18:1 and C18:2) in worker castes. Moreover, we observed that inhibition of most of desaturase genes identified in this study had a negative impact on the survival rate and desiccation tolerance of workers. Interestingly, when normal soldiers were reared together with dsCfor-desatA2-b-treated workers, they exhibited higher mortality, suggesting that desaturase had an impact on trophallaxis among C. formosanus castes. Our findings shed light on the novel roles of desaturase family genes in the eusocial termite C. formosanus.

Effects of n-3 polyunsaturated fatty acid supplementation on appetite: a systematic review and meta-analysis of controlled clinical trials

BACKGROUND

The current studies explore the effect of omega-3 polyunsaturated fatty acids (PUFAs) on appetite.

OBJECTIVE

To examine the effect of omega-3 polyunsaturated fatty acids (n-3 PUFAs) on appetite using a systematic review and meta-analysis of controlled clinical trials (CTs).

PATIENTS AND METHODS

Online databases including PubMed, Scopus, ISI Web of Science, and Google Scholar were searched up to January 2022. A random-effects model was used to compare the overall standardized mean difference in appetite scores between n-3 PUFAs supplemented and control individuals.

RESULTS

Fifteen eligible CTs with 1504 participants (872 for n-3 PUFA supplementation and 632 for placebo groups) were included in our systematic review. The meta-analysis showed no significant difference in overall appetite score between n-3 PUFAs supplemented and control groups (standardized mean difference [SMD] = 0.458, 95% confidence interval [CI] - 0.327, 1.242, P value = 0.25). However, the n-3 PUFA supplementation significantly increased the desire to eat (SMD = 1.07, 95% CI 0.116, 2.029, P = 0.02) compared to control.

CONCLUSION

Although we found no effect of omega-3 supplementation on overall appetite score, it modestly increases the desire to eat. Further CTs evaluating the effect of PUFAs on appetite are still needed to confirm these findings.

Undetected Association Between Fatty Acids and Dementia with Lewy Bodies: A Bidirectional Two-Sample Mendelian Randomization Study

Background

Although observational studies indicated connections between fatty acids (FAs) and Alzheimer's disease and dementia, uncertainty persists regarding how these relationships extend to dementia with Lewy bodies (DLB).

Objective

To explore the potential causal relationships between FAs and the development of DLB, thus clarifying these associations using genetic instruments to infer causality.

Methods

We applied a two-sample Mendelian randomization (MR) and multivariable Mendelian randomization (MVMR) approach. Genetic data were obtained from a DLB cohort, comprising 2,591 cases and 4,027 controls of European descent. Eight FAs, including linoleic acid, docosahexaenoic acid, monounsaturated fatty acid, omega-3 fatty acid, omega-6 fatty acid, polyunsaturated fatty acid, saturated fatty acid, and total fatty acid, were procured from a comprehensive GWAS of metabolic biomarkers of UK Biobank, conducted by Nightingale Health in 2020 (met-d), involving 114,999 individuals. Our analysis included inverse-variance weighted, MR-Egger, weighted-median, simple mode, and weighted-mode MR estimates. Cochran's Q-statistics, MR-PRESSO, and MR-Egger intercept test were used to quantify the heterogeneity and horizontal pleiotropy of instrumental variables.

Results

Only linoleic acid showed a significant genetic association with the risk of developing DLB in the univariate MR. The odds ratio for linoleic acid was 1.337 with a 95% confidence interval of 1.019-1.756 (pIVW = 0.036). Results from the MVMR showed that no FAs were associated with the incidence of DLB.

Conclusions

The results did not support the hypothesis that FAs could reduce the risk of developing DLB. However, elucidating the relationship between FAs and DLB risk holds potential implications for informing dietary recommendations and therapeutic approaches in DLB.

Comprehensive phytochemical characterization of Persea americana Mill. fruit via UPLC/HR-ESI-MS/MS and anti-arthritic evaluation using adjuvant-induced arthritis model

Persea americana Mill. (avocado fruit) has many health benefits when added to our diet due to various pharmacological activities, such as preventing bone loss and inflammation, modulating immune response and acting as an antioxidant. In the current study, the total ethanol extract (TEE) of the fruit was investigated for in vitro antioxidant and anti-inflammatory activity via DPPH and cyclooxygenase enzyme inhibition. Biological evaluation of the antiarthritic effect of the fruit extract was further investigated in vivo using Complete Freund's Adjuvant (CFA) arthritis model, where the average percentages of body weight change, inhibition of paw edema, basal paw diameter/weight and spleen index were estimated for all animal groups. Inflammatory mediators such as serum IL-6 and TNF-α were also determined, in addition to histopathological examination of the dissected limbs isolated from all experimental animals. Eighty-one metabolites belonging to different chemical classes were detected in the TEE of P. americana fruit via UPLC/HR-ESI-MS/MS. Two classes of lyso-glycerophospholipids; lyso-glycerophosphoethanolamines and lysoglycerophosphocholines were detected for the first time in avocado fruit in the positive mode. The TEE of fruit exhibited significant antioxidant and anti-inflammatory activity in vitro. In vivo anti-arthritic activity of the fruit TEE improved paw parameters, inflammatory mediators and spleen index. Histopathological findings showed marked improvements in the arthritic condition of the excised limbs. Therefore, avocado fruit could be proposed to be a powerful antioxidant and antiarthritic natural product.

Lower Adherence to a Mediterranean Diet Is Associated with High Adiposity in Community-Dwelling Older Adults: Results from the Longevity Check-Up (Lookup) 7+ Project

High adiposity impacts health and quality of life in old age, owing to its association with multimorbidity, decreased physical performance, and frailty. Whether a high adherence to a Mediterranean diet (Medi-Diet) is associated with reduced body adiposity in older adults is unclear. The present study was conducted to assess the prevalence of high adiposity in a large sample of community-dwelling older adults. We also explored the relationship between whole-body adiposity estimated through relative fat mass (RFM) and Medi-Diet adherence. Data were obtained from the Longevity Check-up 7+ (Lookup7+) project database. RFM was estimated from anthropometric and personal parameters using a validated equation. RFM was categorized as high if ≥40% in women and ≥30% in men. Information on diet was collected using a food frequency questionnaire, while Medi-Diet adherence was assessed through a modified version of the Medi-Lite scoring system. Analyses were conducted in 2092 participants (mean age 73.1 ± 5.9 years; 53.4% women). Mean RFM was 39.6 ± 5.14% in women and 29.0 ± 3.6% in men. High adiposity was found in 971 (46.4%) participants and was more frequent in those with a low (54.2%) or moderate (46.4%) Medi-Diet adherence compared with the high-adherence group (39.7%, p < 0.001). Logistic regression indicated that older adults with high Medi-Diet adherence were less likely to have a high RFM. Other factors associated with a greater risk of having high adiposity were older age, female sex, and physical inactivity. Our findings support an association between healthy lifestyles, including a greater adherence to a Mediterranean-style diet, and lower body adiposity in older adults.

Tricaprylin, a medium-chain triglyceride, aggravates high-fat diet-induced fat deposition but improves intestinal health

Medium-chain triglycerides (MCTs) are absorbed and metabolized more rapidly than long-chain triglycerides (LCTs) and therefore are considered to have obesity-prevention potential in foods. The effect of adding tricaprylin, an MCT, to food on fat deposition and intestinal health is uncharted. In this study, mice were randomly divided into four groups and fed a normal diet (ND), ND with tricaprylin, a high-fat diet (HFD), or HFD with tricaprylin. Supplementation of 2% tricaprylin in HFD significantly increased the body weight, fat mass, liver weight, adipocyte size in adipose tissue and liver, and upregulated genes related to fat deposition. Metabolomic analysis of serum and adipose tissue revealed that tricaprylin significantly increased the contents of metabolites related to lipid metabolism, triglyceride storage, and fat deposition related signaling pathways. In vitro experiments and molecular docking analysis suggest that octanoic acid, a primary decomposition product of tricaprylin, may promote adipogenic differentiation of preadipocytes by acting as a PPARγ ligand to activate the expression of lipogenesis-related genes. Although supplementation with 2% tricaprylin in HFD cannot reduce fat deposition, it has a beneficial effect on intestinal health. Tricaprylin improved intestinal morphology, digestive enzyme activity, short-chain fatty acid concentration, and intestinal barrier function-related protein expression, while reducing inflammatory factor levels and the abundance of harmful intestinal microorganisms.

Green cabbage supplementation influences the gene expression and fatty acid levels of adipose tissue in Chinese Wanxi White geese

OBJECTIVE

Dietary green cabbage was evaluated for its impact on fatty acid synthetic ability in different adipose tissues during fattening of Wanxi White geese.

METHODS

A total of 256 Wanxi White geese at their 70 days were randomly allocated into 4 groups with 4 replicates and fed 0%, 15%, 30%, and 45% fresh green cabbage (relative to dry matter), respectively, in each group. Adipose tissues (subcutaneous and abdominal fat), liver and blood were collected from 4 birds in each replicate at their 70, 80, 90, and 100 days for fatty acid composition, relative gene expression and serum lipid analysis. Two-way or three-way analysis of variance was used for analysis.

RESULTS

The contents of palmitic acid (C16:0), palmitoleic acid (C16:1), linoleic acid (C18:2), and alpha-linolenic acid (C18:3) were feeding time dependently increased. The C16:0 and stearic acid (C18:0) were higher in abdominal fat, while C16:1, oleic acid (C18:1), and C18:2 were higher in subcutaneous fat. Geese fed 45% green cabbage exhibited highest level of C18:3. Geese fed green cabbage for 30 d exhibited higher level of C16:0 and C18:0 in abdominal fat, while geese fed 30% to 45% green cabbage exhibited higher C18:3 in subcutaneous fat. The expression of Acsl1 (p = 0.003) and Scd1 (p<0.0001) were decreased with green cabbage addition. Interaction between feeding time and adipose tissue affected elongation of long-chain fatty acids family member 6 (Elovl6), acyl-CoA synthetase longchain family member 1 (Acsl1), and stearoly-coA desaturase 1 (Scd1) gene expression levels (p = 0.013, p = 0.003, p = 0.005). Feeding time only affected serum lipid levels of free fatty acid and chylomicron. Higher contents of C16:0, C18:1, and C18:3 were associated with greater mRNA expression of Scd1 (p<0.0001), while higher level of C18:2 was associated with less mRNA expression of Scd1 (p<0.0001).

CONCLUSION

Considering content of C18:2 and C18:3, 30% addition of green cabbage could be considered for fattening for 30 days in Wanxi White geese.

Longitudinal Associations of Healthy Dietary Pattern Scores with Coronary Artery Calcification and Pericardial Adiposity in United States Adults with and without Type 1 Diabetes

BACKGROUND

Pericardial adipose tissue volume (PAT) and coronary artery calcification (CAC) are prognostic indicators for future cardiovascular events; however, no studies have assessed the long-term associations of adherence to dietary patterns (DPs) with PAT and CAC in adults with and without type 1 diabetes (T1D).

OBJECTIVES

We investigated the longitudinal associations of the Mediterranean Diet (MedDiet) and Dietary Approaches to Stop Hypertension (DASH) diet with PAT and CAC progression in adults with and without T1D.

METHODS

The Coronary Artery Calcification in Type 1 Diabetes (CACTI) study is a population-based, prospective study of 652 T1D and 764 nondiabetic mellitus (nonDM) (19-56 y) participants that began in 2000-2002 with follow-up visits in 2003-2004 and 2006-2007. At each visit, food frequency questionnaires were collected and used to develop adherence scores for the MedDiet and DASH diets. PAT and CAC were measured at each visit using electron beam computed tomography. CAC progression was defined as a ≥2.5 mm square root-transformed volume. Mixed effect models were used to conduct statistical analyses.

RESULTS

Combined models found a significant-0.09 cm3 (95% CI: -0.14, -0.03; P = 0.0027) inverse association in PAT for every 1-point increase in the MedDiet score and a significant-0.26 cm3 (95% CI: -0.38, -0.14; P < 0.0001) inverse association in PAT for every 1-point increase in the DASH score. In combined models, the DPs were not significantly associated with lower odds of CAC progression; however, both DPs had significant interactions by diabetes status for CAC. Only the DASH diet was associated with lower odds of CAC progression in the nonDM group (OR: 0.96; 95% CI: 0.93, 0.99; P = 0.0224).

CONCLUSIONS

These data suggest that the DPs are associated with lower PAT, which may reduce future cardiovascular events. The DASH diet may be beneficial for lower odds of CAC progression in those without T1D.

Does Dietary Polyunsaturated Fatty Acid Intake Associate With Bone Mineral Density and Limb Structural Changes in Early Rheumatoid Arthritis?

Background

Rheumatoid arthritis (RA) is an inflammatory disease that can result in bone erosion, lean mass lowering, and increase of fat mass without changes in body weight. The dietary consumption of polyunsaturated fatty acids (PUFAs) has been assessed in many studies due to their potential anti-inflammatory effect.

Aim

The aim of this research was to identify if dietary intake of PUFAs associates with bone mineral density (BMD) and limb structural changes in early rheumatoid arthritis (ERA) compared to a population-based control group. The study was conducted because previous results have been insufficient.

Methods

The study group consisted of 83 ERA patients and 321 control subjects. A dual-energy X-Ray absorptiometry (DXA) machine was used to measure hip, lumbar spine, and radius BMD, as well as arm and leg fat, lean, and bone mass. Dietary habits and inflammatory markers were assessed to evaluate the effects to BMD and limb structural changes.

Results

In ERA subjects, higher dietary consumption of PUFAs was associated with a decrease in arm fat mass (b -28.17, P = .02) and possibly with higher lumbar BMD (b 0.008, P = .058). Limb bone and lean mass changes were not associated with dietary intake of PUFAs.

Conclusion

Balanced nutrition is essential. Consuming PUFAs could be beneficial in ERA preventing structural changes to hands, but additional research is needed.

Legume protein/polysaccharide food hydrogels: Preparation methods, improvement strategies and applications

For the development of innovative foods and nutritional fortification, research into food gel is essential. As two types of rich natural gel material, both legume proteins and polysaccharides have high nutritional value and excellent application potential, attracting wide attention worldwide. Research has focused on combining legume proteins with polysaccharides to form hybrid hydrogels as their combinations show improved texture and water retention compared to single legume protein or single polysaccharide gels, and these properties can be tailored for specific applications. This article reviews hydrogels of common legume proteins and discusses heat induction, pH induction, salt ion induction, and enzyme-induced assembly of legume protein/polysaccharide mixtures. The applications of these hydrogels in fat replacement, satiety enhancement, and delivery of bioactive ingredients are discussed. Challenges for future work are also highlighted.

Fish Oil Supplementation Improves the Repeated-Bout Effect and Redox Balance in 20-30-Year-Old Men Submitted to Strength Training

Herein, we investigated the effect of fish oil supplementation combined with a strength-training protocol, for 6 weeks, on muscle damage induced by a single bout of strength exercise in untrained young men. Sixteen men were divided into two groups, supplemented or not with fish oil, and they were evaluated at the pre-training period and post-training period. We investigated changes before and 0, 24, and 48 h after a single hypertrophic exercise session. Creatine kinase (CK) and lactate dehydrogenase (LDH) activities, plasma interleukin-6 (IL-6) and C-reactive protein (CRP) levels, and the redox imbalance were increased in response to the single-bout session of hypertrophic exercises at baseline (pre-training period) and decreased during the post-training period in the control group due to the repeated-bout effect (RBE). The fish oil supplementation exacerbated this reduction and improved the redox state. In summary, our findings demonstrate that, in untrained young men submitted to a strength-training protocol, fish oil supplementation is ideal for alleviating the muscle injury, inflammation, and redox imbalance induced by a single session of intense strength exercises, highlighting this supplementation as a beneficial strategy for young men that intend to engage in strength-training programs.

High-Fat Diet Related Lung Fibrosis-Epigenetic Regulation Matters

Pulmonary fibrosis (PF) is an interstitial lung disease characterized by the destruction of the pulmonary parenchyma caused by excessive extracellular matrix deposition. Despite the well-known etiological factors such as senescence, aberrant epithelial cell and fibroblast activation, and chronic inflammation, PF has recently been recognized as a metabolic disease and abnormal lipid signature was observed both in serum and bronchoalveolar lavage fluid (BALF) of PF patients and mice PF model. Clinically, observational studies suggest a significant link between high-fat diet (HFD) and PF as manifested by high intake of saturated fatty acids (SFAs) and meat increases the risk of PF and mice lung fibrosis. However, the possible mechanisms between HFD and PF remain unclear. In the current review we emphasize the diversity effects of the epigenetic dysregulation induced by HFD on the fibrotic factors such as epithelial cell injury, abnormal fibroblast activation and chronic inflammation. Finally, we discuss the potential ways for patients to improve their conditions and emphasize the prospect of targeted therapy based on epigenetic regulation for scientific researchers or drug developers.

Lipidomic Characterization and Antioxidant Activity of Macro- and Microalgae Blend

Macro- and microalgae are currently recognized sources of lipids with great nutritional quality and attractive bioactivities for human health promotion and disease prevention. Due to the lipidomic diversity observed among algae species, giving rise to different nutritional and functional characteristics, the mixture of macro- and microalgae has the potential to present important synergistic effects resulting from the complementarity among algae. The aim of this work was to characterize for the first time the lipidome of a blend of macro- and microalgae and evaluate the antioxidant capacity of its lipid fraction. Fatty acids were profiled by GC-MS, the polar lipidome was identified by high resolution LC-MS, and ABTS^+• and DPPH^• assays were used to assess the antioxidant potential. The most abundant fatty acids were oleic (18:1 n-9), α-linolenic (18:3 n-3), and linoleic (18:2 n-6) acids. The lipid extract presented a beneficial n-6/n-3 ratio (0.98) and low values of atherogenic (0.41) and thrombogenic indices (0.27). The polar lipidome revealed 462 lipid species distributed by glycolipids, phospholipids, and betaine lipids, including some species bearing PUFA and a few with reported bioactivities. The lipid extract also showed antioxidant activity. Overall, the results are promising for the valorization of this blend for food, nutraceutical, and biotechnological applications.

The Influence of Nutrition and Physical Activity on Exercise Performance after Mild COVID-19 Infection in Endurance Athletes-CESAR Study

COVID-19 and imposed restrictions are linked with numerous health consequences, especially among endurance athletes (EA). Unfavorable changes in physical activity and nutrition may affect later sports and competition performance. The aims of this study were: (1) to assess the impact of COVID-19 infection and pandemic restrictions on the nutrition and physical activity of EAs and (2) to compare them with the results of cardiopulmonary exercise testing (CPET). In total, 49 EAs (nmale = 43, nfemale = 6, mean age = 39.9 ± 7.8 year., height = 178.4 ± 6.8 cm, weight = 76.3 ± 10.4 kg; BMI = 24.0 ± 2.6 kg·m−2) underwent pre- and post-COVID-19 CPET and fulfilled the dietary and physical activity survey. COVID-19 infection significantly deteriorated CPET performance. There was a reduction in oxygen uptake and in heart rate post-COVID-19 (both p < 0.001). Consuming processed meat and replacing meat with plant-based protein affected blood lactate concentration (p = 0.035). Fat-free mass was linked with consuming unsaturated fatty acids (p = 0.031). Adding salt to meals influenced maximal speed/power (p = 0.024) and breathing frequency (p = 0.033). Dietary and Fitness Practitioners and Medical Professionals should be aware of possible COVID-19 infection and pandemic consequences among EA. The results of this study are a helpful guideline to properly adjust the treatment, nutrition, and training of EA.

Age‐related features of the content of substrates of energy metabolism and body mass index in women residing in the S ubarctic and A rctic regions of R ussia

OBJECTIVES

Age is associated with a number of health risks linked to obesity caused by an imbalance in the main energy substrates-fatty acids (FA) and glucose (Glu). Therefore, the objective of this study was to identify age-related features of the metabolism of fatty acids and Glu, their correlations and the relation with the body mass index (BMI) in women of the local Caucasoid population from two northern regions of Russia with different nature, climate, and geography.

METHODS

We examined women aged 21-60 years born and permanently residing in the Subarctic region (SR) and the Arctic region (AR). The participants were divided into three age groups: 21-35, 36-45, and 46-60 years. The levels of FAs, Glu, and triglycerides (TG) in the blood serum were determined by spectrophotometric and gas chromatographic methods; the values of BMI and TyG (triglyceride glucose) index were calculated. To analyze data, we used the descriptive and correlation analyses by nonparametric methods, as well as multiple linear regression analysis.

RESULTS

With age, the surveyed women demonstrated elevated levels of triglyceride, the majority of the studied fatty acids, BMI and TyG index. For three fatty acids, age-related changes were noted in one of the regions only: stearic and linoleic acids in the SR, and docosahexaenoic acid in the AR; no significant changes were observed for dihomo-γ-linolenic and arachidonic acids. We found elevated Glu levels in women aged 46-60 years residing in the SR. Regional differences were due to higher concentrations of FAs and Glu in the AR. All identified correlations were positive. BMI values were associated with FAs and TG, and in women aged 46-60 years, they were additionally associated with Glu. The latter also correlated with some FAs and TG in this group. TyG index associations with saturated FAs (SFAs) became stronger with age.

CONCLUSIONS

Age has a significant impact on the homeostasis of key energy substrates (Glu, TG, SFAs, monounsaturated FAs), on BMI and TyG index, which are indicators of obesity and insulin resistance. Depending on the region of residence (Subarctic or Arctic), we found changes in the FA profile undersaturation (especially long-chain polyunsaturated FAs) and some specific features of Glu homeostasis (for the age groups of 21-35 and 46-60 years) in women of Caucasoid race in the Russian North. Multiple regression analysis showed that BMI, as well as the region of residence and age, are significant predictors for almost all biochemical parameters, especially for TG and TyG index.

Effect of guanidine acetic acid on meat quality, muscle amino acids, and fatty acids in Tibetan pigs

This study investigated the effects of guanidine acetic acid (GAA) supplementation on growth performance, carcass traits, and meat quality in Tibetan pigs. A total of 18 male Tibetan pigs (21.35 ± 0.99 kg) were randomly assigned to the control (basal diet) and GAA (basal diet + 800 mg/kg GAA) groups for 125 days. Growth performance, carcass traits, and meat quality in pigs, and the chemical composition of Longissimus thoracis (LT) were not altered by GAA. In LT, compared to the control group, dietary GAA increased the superoxide dismutase activity, transcripts of stearoyl CoA desaturase (SCD) and fatty acid synthase (FAS), and contents of glutamate, glutamine, C24:0, C20:3n-6, C20:4n-6, and polyunsaturated fatty acids (P < 0.05), but it decreased the malondialdehyde content (P < 0.001). In back fat, dietary GAA reduced the transcript of peroxisome proliferator-activated receptor γ (PPARγ) and the contents of C10:0, C12:0, C14:0, and C16:0 (P < 0.05), whereas it increased the contents of C22:0, C20:1, C22:1, C24:1, C20:2, C20:3n-3, and C22:2 (P < 0.05). These findings will provide a basis for high-quality Tibetan pork production.

Mulberry leaf polyphenols alleviated high-fat diet-induced obesity in mice

Mulberry leaf is an important medicinal food plant, which is rich in polyphenol compounds. Mulberry leaf polyphenols (MLP) possess significant lipid-lowering and antioxidant effects, and healthcare functions. In this study, the polyphenol content of mulberry leaf ethanol extract was measured using HPLC. The analysis of mulberry leaf extract resulted in the identification of 14 compounds, of which Chlorogenic acid and Quercitrin were the highest. A high-fat diet (HFD)-induced obese mouse model was developed and treated with MLP for 12 weeks to explore their effect on lipid metabolism in HFD-induced obese mice. The results showed that the MLP could inhibit the weight gain and fat cell volume increase in the HFD-induced obese mice in a dose-dependent manner. Further analysis revealed that the MLP decelerated the fatty acid composition in the adipose tissues of HFD-induced obese mice, and significantly increased the polyunsaturated-to-saturated fatty acid (PUFA/SFA) ratio. The real-time quantitative PCR (RT-qPCR) results indicated that the MLP significantly inhibited the down regulation of uncoupling protein (UCP) 1 (UCP1), UCP3, and PR domain zinc finger protein 16 (PRDM16) caused by the HFD. These beneficial effects of MLP on HFD-induced obese mice might be attributed to their ability to change the fatty acid composition of adipose tissue and increase the expression of thermogenesis genes. Overall, the study results suggested that the MLP could serve as potential lipid-lowering and weight-loss functional food and healthcare products.

The fatty acid composition of serum phospholipids in adolescents is associated with body composition in early adulthoods: an eight-year follow-up study

The fatty acid composition is associated with obesity. Omega 3 polyunsaturated fatty acid (PUFA) could have a beneficial role in the prevention and treatment of many disorders, including cardiometabolic diseases. A cohort of 84 men and 131 women were examined in adolescence and after 8 years. Body weight (BW) and fat mass (FM) were measured. The composition of fatty acids (FAs) of serum phospholipids was assessed using gas chromatography. Statistics: PLS method. Aim: to determine the relationships between FAs in adolescence and FM (explanatory variable 1, EV1) and BW (explanatory variable 2, EV2) in adulthood. In the predictive models, a cluster of FAs in boys explained 47.2 % of EV1 and a cluster of 6 FAs in girls explained 32.3 % of EV1 measured in adulthood. FAs measured in adolescents explained 23.7 % of EV2 in early adults regardless of gender. A significant negative association was found between 18:1n-9c and EV1 in males and EV2 in both genders. We found a significant negative association between 18:2n-6 and 20:0 and both EV1 and EV2. In all analyses, we found a significant negative association of 20:1n-9 and 18:3n-3 with EV1-2 in both genders. A significant positive association was found in 20:3n-6 with EV1 and EV2 in males. 20:4n-6 was positively associated with EV1 in females and EV2 in both genders. A positive association between FM and very long chain n- 6 PUFAs was also observed. It is concluded that serum MUFAs and essential PUFAs in adolescence are associated with lower BW and FM in adulthood.

The association of mycoprotein-based food consumption with diet quality, energy intake and non-communicable diseases' risk in the UK adult population using the National Diet and Nutrition Survey (NDNS) years 2008/2009-2016/2017: a cross-sectional study

Mycoprotein is a fungal-based ingredient rich in fibre and protein used in meat substitutes called Quorn. Fibre and protein positively regulate glycaemia, lipidaemia and energy intake which are non-communicable diseases' (NCD) markers. We performed a cross-sectional study to investigate the association of mycoprotein intake with diet quality, nutrient, energy intake and NCD risk within 5507 UK free-living adults from the National Diet and Nutrition Survey from years 2008/2009 to 2016/2017. Dietary approaches to stop hypertension (DASH) and healthy diet index (HDI) were calculated to estimate diet quality. Comparison between mycoprotein consumers (>1 % kcal) and non-consumers, and associations between consumers and nutrient intakes, NCD's risk markers and diet quality were investigated using a survey-adjusted general linear model adjusted for sex, age, BMI, ethnicity, socio-economic, smoking status, region of residency, total energy, energy density, HDI and non-mycoprotein fibre intake. Mycoprotein consumers (3·44 % of the cohort) had a higher intake of dietary fibre (+22·18 %, P < 0·001), DASH score (+23·33 %) and HDI (+8·89 %) (P < 0·001, both) and lower BMI (-4·77 %, P = 0·00) v. non-consumers. There was an association (P = 0·00) between mycoprotein consumers and diet quality scores (+0·19 and +0·26), high fibre (+3·17 g), total and food energy (+3·09 and +0·22 kcal), but low energy density intakes (-0·08 kcal/g, P = 0·04). Consumers were negatively associated with fasting blood glucose (-0·31 mmol/l, P = 0·00) and glycated HbA1c (-0·15 %, P = 0·01). In conclusion, mycoprotein intake is associated with lower glycaemic markers and energy density intake, and high fibre, energy intake and diet quality scores.

Increased Consumption of Unsaturated Fatty Acids Improves Body Composition in a Hypercholesterolemic Chinese Population

While an increase in fat intake and the resulting excess calorie intake are implicated in weight gain, different fat types exert variable effects on body composition, with unsaturated fats showing favorable effects on body composition in Western population. Whether and to what extent these associations apply to Asian population have not been established. We investigated the effects of two separate Asian-based oil blends, rich in unsaturated fats, made from refined rice bran, sesame, and flaxseed oils, in comparison with refined olive oil, on body composition using dual-energy X-ray absorptiometry (DXA), from an 8-week, parallel design, randomized trial in 66 men (58.7 ± 5.71 years old, 23.0 ± 2.38 kg/m²) and 69 postmenopausal women (59.1 ± 5.34 years old, 21.7 ± 2.52 kg/m²), with borderline hypercholesterolemia. Despite increases in mean daily intakes of total energy (approximately +400 kcal/day, female, and approximately +240 kcal/day, male), as well as increases in percentage of calories from fats and proteins and decreases in percentage of calories from carbohydrates during the dietary intervention period, there were no significant changes in total body fat mass in both genders and also in all treatment groups. While total body weight increased slightly (0.36 ± 0.12 kg, p = 0.005) in women during intervention, this was mainly due to gain in lean mass (0.38 ± 0.081 kg, p < 0.0001). Correspondingly, there were reductions in total body fat (%), android fat (%), and gynoid fat (%) in women. No significant differences between the 3 intervention oil types were found in any of the measured parameters in either gender. Increasing relative intakes of unsaturated fats may prevent fat mass gain and circumvent muscle mass loss associated with menopause in older Asian women. Long-term studies are needed to confirm findings. This study had been registered on clinicaltrials.gov (Identifier No.: NCT03964857, https://www.clinicaltrials.gov/ct2/show/NCT03964857).

Evaluation of Different Standard Amino Acids to Enhance the Biomass, Lipid, Fatty Acid, and γ-Linolenic Acid Production in Rhizomucor pusillus and Mucor circinelloides

In this study, 18 standard amino acids were tested as a single nitrogen source on biomass, total lipid, total fatty acid (TFA) production, and yield of γ-linolenic acid (GLA) in Rhizomucor pusillus AUMC 11616.A and Mucor circinelloides AUMC 6696.A isolated from unusual habitats. Grown for 4 days at 28°C, shaking at 150 rpm, the maximum fungal biomass for AUMC 6696.A was 14.6 ± 0.2 g/L with arginine and 13.68 ± 0.1 g/L with asparagine, when these amino acids were used as single nitrogen sources, while AUMC 11616.A maximum biomass was 10.73 ± 0.8 g/L with glycine and 9.44 ± 0.6 g/L with valine. These were significantly higher than the ammonium nitrate control (p &lt; 0.05). The highest levels of TFA were achieved with glycine for AUMC 11616.A, 26.2 ± 0.8% w/w of cell dry weight, and glutamic acid for AUMC 6696.A, 23.1 ± 1.3%. The highest GLA yield was seen with proline for AUMC 11616.A, 13.4 ± 0.6% w/w of TFA, and tryptophan for AUMC 6696.A, 12.8 ± 0.3%, which were 38% and 25% higher than the ammonium tartrate control. The effects of environmental factors such as temperature, pH, fermentation time, and agitation speed on biomass, total lipids, TFA, and GLA concentration of the target strains have also been investigated. Our results demonstrated that nitrogen assimilation through amino acid metabolism, as well as the use of glucose as a carbon source and abiotic factors, are integral to increasing the oleaginicity of tested strains. Few studies have addressed the role of amino acids in fermentation media, and this study sheds light on R. pusillus and M. circinelloides as promising candidates for the potential applications of amino acids as nitrogen sources in the production of lipids.

Human Milk Oligosaccharides and Bacterial Profile Modulate Infant Body Composition during Exclusive Breastfeeding

Human milk is a complex and variable ecosystem fundamental to the development of newborns. This study aimed to investigate relationships between human milk oligosaccharides (HMO) and human milk bacterial profiles and infant body composition. Human milk samples (n = 60) were collected at two months postpartum. Infant and maternal body composition was measured with bioimpedance spectroscopy. Human milk bacterial profiles were assessed using full-length 16S rRNA gene sequencing and 19 HMOs were quantitated using high-performance liquid chromatography. Relative abundance of human milk bacterial taxa were significantly associated with concentrations of several fucosylated and sialylated HMOs. Individual human milk bacteria and HMO intakes and concentrations were also significantly associated with infant anthropometry, fat-free mass, and adiposity. Furthermore, when data were stratified based on maternal secretor status, some of these relationships differed significantly among infants born to secretor vs non-secretor mothers. In conclusion, in this pilot study the human milk bacterial profile and HMO intakes and concentrations were significantly associated with infant body composition, with associations modified by secretor status. Future research designed to increase the understanding of the mechanisms by which HMO and human milk bacteria modulate infant body composition should include intakes in addition to concentrations.

Perinatal Polyunsaturated Fatty Acid Status and Obesity Risk

High obesity rates in almost all regions of the world prompt an urgent need for effective obesity prevention. Very good scientific evidence from cell culture and rodent studies show that the availability of essential polyunsaturated fatty acids (PUFA) and their long-chain polyunsaturated derivatives, namely, arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid, influence adipogenesis; for this reason, early life status may influence later obesity risk. The respective PUFA effects could be mediated via their eicosanoid derivatives, their influence on cell membrane properties, the browning of white adipose tissue, changes to the offspring gut microbiome, their influence on developing regulatory circuits, and gene expression during critical periods. Randomized clinical trials and observational studies show divergent findings in humans, with mostly null findings but also the positive and negative effects of an increased n-3 to n-6 PUFA ratio on BMI and fat mass development. Hence, animal study findings cannot be directly extrapolated to humans. Even though the mechanistic data basis for the effects of n-3 PUFA on obesity risk appears promising, no recommendations for humans can be derived at present.

Beneficial Effects of a Specially Designed Home Meal Replacement on Cardiometabolic Parameters in Individuals with Obesity: Preliminary Results of a Randomized Controlled Clinical Trial

We aimed to investigate if a home meal replacement (HMR), designed with a low ω-6/ω-3 fatty acid ratio, improves cardiometabolic parameters, including metabolic syndrome (MetS) in obese individuals. We conducted a monocentric, controlled, randomized crossover trial. The HMR contains higher protein and fat content, lower carbohydrate content, and a lower ω6FA/ω3FA ratio than the regular diet. Sixty-four participants were randomized into two groups and switched to the other group following a 4-week intervention. While subjects in the HMR group were provided three HMRs daily, those in the control group were requested to maintain their regular dietary pattern. We conducted paired t-tests, repeated measures analysis of variance, and McNemar tests before and after the intervention. Body mass index (BMI) and weight were lower in the HMR group after adjusting for age, sex, and total energy intake and significantly changed in the between-group differences. The waist circumference, systolic blood pressure, triglycerides, triglyceride–glucose index, and triglyceride to high-density lipoprotein cholesterol ratio were reduced in the HMR group (all p < 0.05). The percentage of subjects with MetS significantly decreased from 39.1% at baseline to 28.1% post-intervention (p = 0.035). Using the HMR for 4 weeks reduced the BMI, weight, and MetS prevalence in individuals with obesity. This trial was registered at clinicaltrials.gov (NCT04552574).

Pathogenesis of obesity and cardiometabolic diseases: From the legacy of Ancel Keys to current concepts

Several areas of research into the prevention and treatment of obesity today can be traced to one or more of the scientific works pioneered by Ancel Keys between the 1930s to 1970s in fields that cut across the physiology of extremes and public health nutrition. These range from his classical studies into how body and mind respond to chronic exposure to hypoxia in "The Physiology of Life at High Altitudes" or to simulated famine under controlled laboratory conditions in "The Biology of Human Starvation", the impact of diet and lifestyle on cardiovascular morbidity and mortality in "The Seven Countries Study," to the "Indices of Relative Weight and Obesity" in which he identified what has since been the most widely utilized diagnostic tool to monitor obesity across populations worldwide and which he coined as the body mass index. The contribution of Ancel Keys to medical sciences through his observations, analytical approaches, and research output of his classic studies, and how these have (and continue) to impact on a plethora of current concepts in obesity research today, are embodied in the eight review articles that constitute this supplement reporting the proceedings of the 10th Fribourg Obesity Research Conference. The aim of this introductory paper is to put into perspective the legacy of Ancel Keys to current concepts that are encapsulated in these review articles that cover research areas that include (i) the diagnosis of obesity for health risks; (ii) the role of dietary fat types in the pathogenesis of obesity and cardiometabolic diseases; (iii) the rationale, efficacy and safety of low carbohydrate ketogenic diets, or the therapeutic potential of hypoxic conditioning, in weight management programs; (iv) the psychological and physiological basis of the "famine reaction" that counters therapeutic dieting and facilitates weight regain; and (v) the potential impact of weight cycling and yoyo dieting on risks for later obesity and cardiometabolic diseases.