The mechanisms of pH regulation on promoting volatile fatty acids production from kitchen waste.

The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH adjustment. The results showed that pH 8 was considered to be the most suitable condition for acid production, especially for the formation of acetic acid and propionic acid. The average value of total volatile fatty acid at pH 8 was 8814 mg COD/L, 1.5 times of that under blank condition. The average yield of acetic acid and propionic acid was 3302 mg COD/L and 2891 mg COD/L, respectively. The activities of key functional enzymes such as phosphotransacetylase, acetokinase, oxaloacetate transcarboxylase and succinyl-coA transferase were all enhanced. To further explore the regulatory mechanisms within the system, the distribution of microorganisms at different levels in the fermentation system was obtained by microbial sequencing, results indicating that the relative abundances of Clostridiales, Bacteroidales, Chloroflexi, Clostridium, Bacteroidetes and Propionibacteriales, which were great contributors for the hydrolysis and acidification, increased rapidly at pH 8 compared with the blank group. Besides, the proportion of genes encoding key enzymes was generally increased, which further verified the mechanism of hydrolytic acidification and acetic acid production of organic matter under pH regulation.

Association between blood metabolites and basal cell carcinoma risk: a two-sample Mendelian randomization study.

Background: Circulating metabolites, which play a crucial role in our health, have been reported to be disordered in basal cell carcinoma (BCC). Despite these findings, evidence is still lacking to determine whether these metabolites directly promote or prevent BCC's progression. Therefore, our study aims to examine the potential effects of circulating metabolites on BCC progression. Material and methods: We conducted a two-sample Mendelian randomization (MR) analysis using data from two separate genome-wide association studies (GWAS). The primary study included data for 123 blood metabolites from a GWAS with 25,000 Finnish individuals, while the secondary study had data for 249 blood metabolites from a GWAS with 114,000 UK Biobank participants.GWAS data for BCC were obtained from the UK Biobank for the primary analysis and the FinnGen consortium for the secondary analysis. Sensitivity analyses were performed to assess heterogeneity and pleiotropy. Results: In the primary analysis, significant causal relationships were found between six metabolic traits and BCC with the inverse variance weighted (IVW) method after multiple testing [P < 4 × 10-4 (0.05/123)]. Four metabolic traits were discovered to be significantly linked with BCC in the secondary analysis, with a significance level of P < 2 × 10-4 (0.05/249). We found that all the significant traits are linked to Polyunsaturated Fatty Acids (PUFAs) and their degree of unsaturation. Conclusion: Our research has revealed a direct link between the susceptibility of BCC and Polyunsaturated Fatty Acids and their degree of unsaturation. This discovery implies screening and prevention of BCC.

Association between fatty acids intake and bone mineral density in adolescents aged 12-19: NHANES 2011-2018.

Background: The relationship between the intake of dietary fatty acids (FA) and bone mineral density (BMD) has been the subject of prior investigations. However, the outcomes of these studies remain contentious. The objective of this research is to examine the link between dietary FA consumption among adolescents and BMD. Methods: This study utilized high-quality data from the National Health and Nutrition Examination Survey database, spanning 2011 to 2018, to explore the association between dietary fatty acids and bone health indicators in adolescents, including BMD and bone mineral content (BMC). Analyses were performed using weighted multivariate linear regression models, incorporating detailed subgroup analysis. Results: The study included 3440 participants. Analysis demonstrated that intake of saturated fatty acids (SFA) was positively correlated with total BMD, left arm BMD, total BMC, and left arm BMC. Monounsaturated fatty acid (MUFA) intake was positively correlated with BMC across most body parts, though it showed no correlation with BMD. Intake of polyunsaturated fatty acids (PUFA) was significantly inversely correlated with both BMD and BMC in most body parts. Additionally, subgroup analysis indicated that variables such as sex, age, standing height, and race significantly influenced the correlation between FA intake and BMD. Conclusions: Our study indicates that dietary intake of SFA may benefit to BMD in adolescents, in contrast to PUFA and MUFA. Therefore, we recommend that adolescents maintain a balanced intake of SFA to promote optimal bone mass development while preserving metabolic health.

Space-use strategy drives fine-scale spatial variation of chlorinated paraffins in indo-pacific humpback dolphins.

Contaminant accumulation in organisms can be influenced by both biological traits and environmental conditions. However, delineating the main factors affecting contaminant burdens in organisms remains challenging. Here, we conducted an initial investigation into the impact of diet and habitat on the accumulation of short- (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in Indo-Pacific humpback dolphins (2003-2020, n = 128) from the Pearl River Estuary (PRE), a highly polluted estuary in China. The detected levels of SCCPs (5897 ± 3480 ng g-1 lw) and MCCPs (13,960 ± 8285 ng g-1 lw) in blubber samples of humpback dolphin are the highest among recorded values marine mammals. Both SCCPs and MCCPs exhibited biomagnification factor values exceeding 1, suggesting their biomagnification potential within the dolphins and their diet. Quantitative diet analysis using the dolphin fatty acid signatures revealed that humpback dolphins inhabiting the western PRE consumed a larger proportion of carnivorous fish than those from the eastern PRE. However, spatial analysis showed that humpback dolphins in the western PRE contained lower SCCP/MCCP concentrations than those from the eastern PRE. Based on these findings we suggest that, compared to diet differences, spatial variations of SCCPs/MCCPs in humpback dolphins may be predominantly influenced by their space-use strategies, as the eastern PRE is closer to the pollutant discharge source and transfer routes.

Mechanisms of regulation of glycolipid metabolism by natural compounds in plants: effects on short-chain fatty acids.

BACKGROUND: Natural compounds can positively impact health, and various studies suggest that they regulate glucose‒lipid metabolism by influencing short-chain fatty acids (SCFAs). This metabolism is key to maintaining energy balance and normal physiological functions in the body. This review explores how SCFAs regulate glucose and lipid metabolism and the natural compounds that can modulate these processes through SCFAs. This provides a healthier approach to treating glucose and lipid metabolism disorders in the future. METHODS: This article reviews relevant literature on SCFAs and glycolipid metabolism from PubMed and the Web of Science Core Collection (WoSCC). It also highlights a range of natural compounds, including polysaccharides, anthocyanins, quercetins, resveratrols, carotenoids, and betaines, that can regulate glycolipid metabolism through modulation of the SCFA pathway. RESULTS: Natural compounds enrich SCFA-producing bacteria, inhibit harmful bacteria, and regulate operational taxonomic unit (OTU) abundance and the intestinal transport rate in the gut microbiota to affect SCFA content in the intestine. However, most studies have been conducted in animals, lack clinical trials, and involve fewer natural compounds that target SCFAs. More research is needed to support the conclusions and to develop healthier interventions. CONCLUSIONS: SCFAs are crucial for human health and are produced mainly by the gut microbiota via dietary fiber fermentation. Eating foods rich in natural compounds, including fruits, vegetables, tea, and coarse fiber foods, can hinder harmful intestinal bacterial growth and promote beneficial bacterial proliferation, thus increasing SCFA levels and regulating glucose and lipid metabolism. By investigating how these compounds impact glycolipid metabolism via the SCFA pathway, novel insights and directions for treating glucolipid metabolism disorders can be provided.

Unravelling metabolic factors impacting iNKT cell biology in obesity.

Obesity and related diseases have reached epidemic proportions and continue to rise. Beyond creating an economical burden, obesity and its co-morbidities are associated with shortened human life expectancy. Despite major advances, the underlying mechanisms of obesity remain not fully elucidated. Recently, several studies have highlighted that various immune cells are metabolically reprogrammed in obesity, thereby profoundly affecting the immune system. This sheds light on a new field of interest: the impact of obesity-related systemic metabolic changes affecting immune system that could lead to immunosurveillance loss. Among immune cells altered by obesity, invariant Natural Killer T (iNKT) cells have recently garnered intense focus due to their ability to recognize lipid antigen. While iNKT cells are well-described to be affected by obesity, how and to what extent immunometabolic factors (e.g., lipids, glucose, cytokines, adipokines, insulin and free fatty acids) can drive iNKT cells alterations remains unclear, but represent an emerging field of research. Here, we review the current knowledge on iNKT cells in obesity and discuss the immunometabolic factors that could modulate their phenotype and activity.

Properties and functions of acylated starch with short-chain fatty acids: a comprehensive review.

Short-chain fatty acids (SCFAs) are the primary energy source of colonic epithelial cells, but oral SCFAs are digested, absorbed, or degraded before reaching the colon. The acylated starch with SCFAs can be fermented and release specific SCFAs under the action of colonic intestinal microbiota. This review first introduces the preparation method, reaction mechanism, and substitution factors. Second, the structure, physical and chemical properties, in vitro function, and mechanism of acylated starch were expounded. Finally, the application of acylated starch in foods is introduced, and its safety is evaluated, providing a basis for the further development of acylated starch-based foods. The acylated starch obtained by different acylation types and preparation methods is different in particle, molecular, and crystal structures, leading to changes in the function and physicochemical properties. Meanwhile, acylated starch has the functional potential of targeted delivery of SCFAs to the colon, which can increase SCFAs in feces and intestine, selectively regulate the intestinal microbiota, and produce a prebiotic effect conducive to host health. The safety of acetylated starch has been supported by relevant studies, which have been widely used in various food fields and have great potential in the food industry.

Metabolomics reveals dysregulated all-trans retinoic acid and polyunsaturated fatty acid metabolism contribute to PXR-induced hepatic steatosis in mice.

Activation of pregnane X receptor (PXR) by xenobiotics has been associated with metabolic diseases. This study aimed to reveal the impact of PXR activation on hepatic metabolome and explore novel mechanisms underlying PXR-mediated lipid metabolism disorder in the liver. Wild-type and PXR-deficient male C57BL/6 mice were used as in vivo models, and hepatic steatosis was induced by pregnenolone-16α-carbonitrile, a typical rodent PXR agonist. Metabolomic analysis of liver tissues showed that PXR activation led to significant changes in metabolites involved in multiple metabolic pathways previously reported, including lipid metabolism, energy homeostasis, and amino acid metabolism. Moreover, the level of hepatic all-trans retinoic acid (ATRA), the main active metabolite of vitamin A, was significantly increased by PXR activation, and genes involved in ATRA metabolism exhibited differential expression following PXR activation or deficiency. Consistent with previous research, the expression of downstream target genes of peroxisome proliferator-activated receptor α (PPARα) was decreased. Analysis of fatty acids by Gas Chromatography-Mass Spectrometer further revealed changes in polyunsaturated fatty acid metabolism upon PXR activation, suggesting inhibition of PPARα activity. Taken together, our findings reveal a novel metabolomic signature of hepatic steatosis induced by PXR activation in mice.

Screening of lactic acid bacteria with the ability to reduce goaty flavor related fatty acids in goat milk.

In this study, we conducted sensory evaluation and gas chromatography-mass spectrometry analysis on fermented goat milk samples prepared by 12 strains of lactic acid bacteria (LAB) isolated from goat milk to screen for strains with the ability to reduce the goaty flavor. The bacterial counts of fermented goat milk was 7.07-9.01 log CFU/mL. The electronic nose distinguished fresh goat milk (FGM) and fermented goat milk, and the electronic tongue results showed that Leuconostoc citreum 1, 4, 20, 22, 32, and 57, Latilactobacillus curvatus 144 and 147 imparted fermented goat milk a taste different from FGM. Overall, Leuconostoc citreum 57, Leuconostoc citreum 126, Latilactobacillus curvatus 142, Latilactobacillus curvatus 143, and Latilactobacillus curvatus 147 were screened with the ability to improve the flavor of goat milk. They gave fermented goat milk a goat flavor score lower than or equal to FGM. And the fermented goat milk samples 57, 126, 142, 143, and 147 contained 25, 22, 15, 24, and 17 volatile flavor compounds, respectively, with a greater variety and content of ketones and aldehydes and lower levels of hexanoic acid, octanoic acid, and decanoic acid than FGM. However, the pH and WHC results indicated that the application of these strains as secondary cultures is necessary. Our finding provides basic research data to improve the flavor of goat milk products.

Milk components as potential indicators of energy status in early lactation Holstein dairy cows from two farms.

Negative energy balance (NEB) is a serious problem in most dairy cows. It occurs most frequently after calving, when cows are unable to consume sufficient DM to meet their energy requirements during early lactation. During NEB, the breakdown of fat stores releases non-esterified fatty acids (NEFAs) into the bloodstream. High blood concentrations of NEFAs cause health problems such as ketosis, fatty liver syndrome, and enhanced susceptibility to infections. These issues may substantially increase premature culling from the herd. Serum NEFA concentrations are often used as a direct marker of energy metabolism. However, because the direct measurement of serum NEFAs is difficult under commercial conditions, alternative indicators, such as milk components, have been increasingly investigated for their use in estimating energy balance. The objectives of this study were to (1) evaluate the relationships between serum NEFA concentrations and selected milk components in cows from two farms during the first 5 weeks of lactation, and to (2) develop a model valid for both herds for predicting serum NEFA concentrations using milk components. A total of 121 lactating Holstein cows from two different farms were included in the experiment. Blood samples were collected for NEFA analysis on days 7 (± 3), 14 (± 3), 21 (± 3), and 35 (± 3) after calving. Composite milk samples were collected during afternoon milking on the same days as blood sampling. Concentrations of fat, protein, lactose, and milk fatty acids (FAs) were determined using Fourier-transform IR spectroscopy analysis. The strongest correlations (r > 0.43) were recorded between serum NEFAs and milk long-chain FAs, monounsaturated FAs, C18:0, and C18:1 within each farm and for both farms combined. Two prediction models for serum log(NEFA) using milk components as predictors were developed by stepwise regression. The prediction model with the best fit (R2 = 0.52) included days in milk, fat-to-protein ratio, and C18:1, C18:12 and C14:0 expressed as g/100 g of milk fat. An essential finding is that, despite different concentrations of NEFAs, and of most milk components observed in the evaluated herds, there were no significant interactions between farm and any of the FAs, so the same regression coefficients could be used for the prediction models in both farms. Validation of these findings in a greater number of herds would allow for the use of milk FAs to identify energy-imbalanced cows in herds under different farm conditions.

Targeted Metabolomic Analysis of Serum Free Fatty Acids: Lipidomics Disturbance in Patients with Superior Limbic Keratoconjunctivitis.

This study aimed to identify and quantify free fatty acids (FFAs), secretory phospholipase A2 group IIa (sPLA2-IIa) and cytosolic phospholipase A2 (cPLA2) in serum of superior limbic keratoconjunctivitis (SLK) patients and explored the association between FFAs, sPLA2-IIa and cPLA2 variations and SLK. Targeted metabolomic analysis of FFAs in serum was performed by gas chromatography tandem mass spectrometry (GC-MS/MS) analysis on 16 SLK patients (43.88±7.88 years; female: 62.50%) and 25 healthy controls (43.12±7.88 years; female: 64.00%). Qualitative and absolute quantitative results of FFAs were obtained and classified according to gender and thyroid tests. Differential lipid metabolites, metabolomic pathways and biomarkers were further evaluated. The serum sPLA2-IIa and cPLA2 were determined by enzyme linked immunosorbent assay (ELISA). Among 40 FFAs identified, 6 FFAs showed significant changes (P<0.05) in SLK patients, including 4 decreased and 2 increased. They were mainly related to unsaturated fatty acid biosynthesis, α-linolenic acid and linoleic acid metabolism, and fatty acid biosynthesis. When dividing the data by gender or abnormal thyroid tests, some comparable FFAs alterations displayed in SLK patients. The ROC analysis revealed that the AUC values of linoleic acid, γ-linolenic acid, cis-8,11,14-eicosatrienoic acid, stearic acid, and palmitic acid, were all greater than 0.8. The serum concentrations of sPLA2-IIa and cPLA2 in patients with SLK were significantly higher than that in healthy controls. Lipidomics disturbance might be the potential mechanism of SLK. Serum FFA biomarkers associated with SLK have potential for the diagnosis and treatment of the disease.

Enhancing phenolic and lipid compound production in oat bran via acid pretreatment and solid-state fermentation with Aspergillus niger.

Oat (Avena sativa) processing generates a large amount of by-products, especially oat bran. These by-products are excellent sources of bioactive compounds such as polyphenols and essential fatty acids. Therefore, enhancing the extraction of these bioactive substances and incorporating them into the human diet is critical. This study investigates the effect of acid pretreatment on the solid-state fermentation of oat bran with Aspergillus niger, with an emphasis on the bioaccessibility of phenolic acids and lipid profile. The results showed a considerable increase in reducing sugars following acid pretreatment. On the sixth day, there was a notable increase in the total phenolic content, reaching 58.114 ± 0.09mg GAE/g DW, and the vanillic acid level significantly rose to 77.419 ± 0.27µg/g DW. The lipid profile study revealed changes ranging from 4.66% in the control to 7.33% on the sixth day of SSF. Aside from biochemical alterations, antioxidant activity measurement using the DPPH technique demonstrated the maximum scavenging activity on day 4 (83.33%). This study highlights acid pretreatment's role in enhancing bioactive compound accessibility in solid-state fermentation and its importance for functional food development.

Preliminary Study on the Restoration of the Phospholipid Profile in Serum from Patients with COVID-19 by Treatment with Vitamin E.

SARS-CoV-2 is an obligatory intracellular pathogen that requires a lipid bilayer membrane for its transport to build its nucleocapsid envelope and fuse with the host cell. The biological membranes are constituted by phospholipids (PLs), and vitamin E (Vit E) protects them from oxidative stress (OS). The aim of this study was to demonstrate if treatment with Vit E restores the modified profile of the FA in PLs in serum from patients with coronavirus disease-19 (COVID-19). We evaluated Vit E, total fatty acids (TFAs), fatty acids of the phospholipids (FAPLs), total phospholipids (TPLs), 8-isoprostane, thromboxane B2 (TXB2), prostaglandins (PGE2 and 6-keto-PGF1α), interleukin-6 (IL-6), and C-reactive protein (CRP) in serum from 22 COVID-19 patients before and after treatment with Vit E and compared the values with those from 23 healthy subjects (HSs). COVID-19 patients showed a decrease in Vit E, TPLs, FAPLs, and TFAs in serum in comparison to HSs (p ≤ 0.01), and Vit E treatment restored their levels (p ≤ 0.04). Likewise, there was an increase in IL-6 and CRP in COVID-19 patients in comparison with HSs (p ≤ 0.001), and treatment with Vit E decreased their levels (p ≤ 0.001). Treatment with Vit E as monotherapy can contribute to restoring the modified FA profile of the PLs in the SARS-CoV-2 infection, and this leads to a decrease in lipid peroxidation, OS, and the inflammatory process.

Phytotoxic Strains of Fusarium commune Isolated from Truffles.

Most Fusarium species are known as endophytes and/or phytopathogens of higher plants and have a worldwide distribution. Recently, information discovered with molecular tools has been also published about the presence of these fungi in the microbiome of truffle fruiting bodies. In the present work, we isolated and identified three Fusarium strains from truffle fruiting bodies. All isolates were assigned to the same species, F. commune, and the strains were deposited in the All-Russian Collection of Microorganisms under accession numbers VKM F-5020, VKM F-5021, and VKM F-5022. To check the possible effects of the isolated strains on the plants, the isolates were used to infect sterile seedlings of Sarepta mustard (Brassica juncea L.). This model infection led to a moderate suppression of the photosynthetic apparatus activity and plant growth. Here, we present characteristics of the F. commune isolates: description of the conidial morphology, pigmentation, and composition of the mycelium fatty acids. Overall, this is the first description of the Fusarium cultures isolated from truffle fruiting bodies. Possible symbiosis of the F. commune strains with truffles and their involvement in the cooperative fatty acid production are proposed.

Marine-Derived Lipases for Enhancing Enrichment of Very-Long-Chain Polyunsaturated Fatty Acids with Reference to Omega-3 Fatty Acids.

Omega-3 fatty acids are essential fatty acids that are not synthesised by the human body and have been linked with the prevention of chronic illnesses such as cardiovascular and neurodegenerative diseases. However, the current dietary habits of the majority of the population include lower omega-3 content compared to omega-6, which does not promote good health. To overcome this, pharmaceutical and nutraceutical companies aim to produce omega-3-fortified foods. For this purpose, various approaches have been employed to obtain omega-3 concentrates from sources such as fish and algal oil with higher amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Among these techniques, enzymatic enrichment using lipase enzymes has gained tremendous interest as it is low in capital cost and simple in operation. Microorganism-derived lipases are preferred as they are easily produced due to their higher growth rate, and they hold the ability to be manipulated using genetic modification. This review aims to highlight the recent studies that have been carried out using marine lipases for the enrichment of omega-3, to provide insight into future directions. Overall, the covalent bond-based lipase immobilization to various support materials appears most promising; however, greener and less expensive options need to be strengthened.

Fatty acid analysis in microalgal mono- and polycultures using diffuse reflectance infrared Fourier transform spectroscopy coupled with partial least squares analysis.

Fatty acids are of particular interest for industrial applications of microalgal feedstock, as these have a wide array of different uses such as pharmaceuticals and biofuels. Fourier transform infrared (FTIR) spectroscopic techniques used in combination with multivariate prediction modeling are showing great potential as analytical methods for characterizing microalgal biomass. The present study investigated the use of diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) coupled with partial least squares regression (PLSR) to estimate fatty acid contents in microalgae. A prediction model for microalgal samples was developed using algae cultivated in both Bold's basal medium (BBM) and sterilized municipal wastewater under axenic conditions, as well as algal polycultures cultivated in open raceway ponds using untreated municipal wastewater influent. This universal prediction model was able to accurately predict microalgal samples of either type with high accuracy (RMSEP = 1.38, relative error = 0.14) and reliability (R2 > 0.92). DRIFTS in combination with PLSR is a rapid method for determining fatty acid contents in a wide variety of different microalgal samples with high accuracy. The use of spectral characterization techniques offers a reliable and environmentally friendly alternative to traditional labor intensive techniques based on the use of toxic chemicals.

Metabolic flux in macrophages in obesity and type-2 diabetes.

Recent literature extensively investigates the crucial role of energy metabolism in determining the inflammatory response and polarization status of macrophages. This rapidly expanding area of research highlights the importance of understanding the link between energy metabolism and macrophage function. The metabolic pathways in macrophages are intricate and interdependent, and they can affect the polarization of macrophages. Previous studies suggested that glucose flux through cytosolic glycolysis is necessary to trigger pro-inflammatory phenotypes of macrophages, and fatty acid oxidation is crucial to support anti-inflammatory responses. However, recent studies demonstrated that this understanding is oversimplified and that the metabolic control of macrophage polarization is highly complex and not fully understood yet. How the metabolic flux through different metabolic pathways (glycolysis, glucose oxidation, fatty acid oxidation, ketone oxidation, and amino acid oxidation) is altered by obesity- and type 2 diabetes (T2D)-associated insulin resistance is also not fully defined. This mini-review focuses on the impact of insulin resistance in obesity and T2D on the metabolic flux through the main metabolic pathways in macrophages, which might be linked to changes in their inflammatory responses. We closely evaluated the experimental studies and methodologies used in the published research and highlighted priority research areas for future investigations.

Association between fatty acid intake and age-related macular degeneration: a meta-analysis.

Objective: The association of age-related macular degeneration (AMD) with the intake of high and low fatty acids (FAs), respectively, remains controversial. To this end, we performed a comprehensive meta-analysis of all the existing studies on the association of various intake levels of FA subtypes with AMD to determine these associations. Methods: A systematic search of PubMed, Web of Science, Cochrane Library, and EMBASE databases was conducted from inception to September 2023. To compare the highest and lowest groups, odds ratio (OR) with 95% confidence intervals (CIs) was analyzed with a random-effects model/fixed-effects model. Results: A high intake of omega-3 LCPUFAs (OR:0.67; 95%CI:[0.51, 0.88]; p = 0.004), DHA (OR:0.80; 95%CI:[0.70, 0.90]; p < 0.001), EPA (OR:0.91; 95%CI:[0.86, 0.97]; p = 0.004), and simultaneous intake of DHA and EPA (OR:0.79; 95%CI:[0.67, 0.93]; p = 0.035) significantly reduced the risk of overall AMD. Conversely, a high intake of trans-FAs (OR: 2.05; 95%CI: [1.29, 3.25]; p = 0.002) was significantly related to an increased risk of advanced AMD compared to the low-intake group. The subgroup analysis results are shown in the articles. Conclusion: Increasing dietary intake of omega-3 LCPUFAs, specifically DHA, and EPA, or the simultaneous intake of DHA and EPA, is significantly associated with a reduced risk of overall AMD. Various subtypes of omega-3 also have a significant association with a reduced risk of different stages of AMD. The high intake of trans-fatty acids (TFAs) is significantly and positively correlated with the risk of advanced AMD. This could further support the idea that consuming foods rich in omega-3 LCPUFAs and reducing consumption of foods rich in TFAs may prevent AMD. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023467227.

Colorectal cancer and inulin supplementation: the good, the bad, and the unhelpful.

The prebiotic inulin has been vaunted for its potential to reduce the risk of colorectal cancer. Inulin fermentation resulting in the production of short-chain fatty acids, primarily butyrate, has been reported to be associated with properties that are beneficial for gut health and has led to an increased consumption of inulin in the Western population through processed food and over-the-counter dietary supplements. However, in clinical trials, there is limited evidence of the efficacy of inulin in preventing colorectal cancer. Moreover, recent data suggest that improper inulin consumption may even be harmful for gastro-intestinal health under certain circumstances. The main objective of this review is to provide insight into the beneficial and potentially detrimental effects of inulin supplementation in the context of colorectal cancer prevention and enhancement of treatment efficacy.

An atlas of GPCRs in dopamine neurons: Identification of the free fatty acid receptor 4 as a regulator of food and water intake.

Midbrain dopaminergic neurons (DANs) are subject to extensive metabotropic regulation, but the repertoire of G protein-coupled receptors (GPCRs) present in these neurons has not been mapped. Here, we isolate DANs from Dat-eGFP mice to generate a GPCR atlas by unbiased qPCR array expression analysis of 377 GPCRs. Combined with data mining of scRNA-seq databases, we identify multiple receptors in DAN subpopulations with 38 of these receptors representing the majority of transcripts. We identify 41 receptors expressed in midbrain DANs but not in non-DAN midbrain cells, including the free fatty acid receptor 4 (FFAR4). Functional expression of FFAR4 is validated by ex vivo Ca2+ imaging, and in vivo experiments support that FFAR4 negatively regulates food and water intake and bodyweight. In addition to providing a critical framework for understanding metabotropic DAN regulation, our data suggest fatty acid sensing by FFAR4 as a mechanism linking high-energy intake to the dopamine-reward pathway.