Branched-Chain Fatty Acids as Mediators of the Activation of Hepatic Peroxisome Proliferator-Activated Receptor Alpha by a Fungal Lipid Extract

Branched-chain fatty acids affect the expression of fatty acid synthase and C-reactive protein genes in the hepatocyte cell line

Fatty acids (FAs) are known to play an important role in human metabolism; however, still little is known about the functions of certain FA classes present in blood at relatively low concentrations. Examples of such compounds include branched-chain fatty acids (BCFAs). Recently, lowered BCFAs blood concentration was noticed in obese patients. An inverse correlation was found between serum concentrations of BCFAs and triglyceride levels, as well as C-reactive protein (CRP) concentration. Obesity is the most frequently observed component of metabolic syndrome and both disorders are accompanied by the dysregulation of FAs metabolism. However, not all of them are well understood. Our study is the first attempt at presenting the opposite effects of an iso-BCFA (14-methylpentadecanoic acid, 14-MPA) and an anteiso-BCFA (12-methyltetradecanoic acid, 12-MTA) on selected genes related to fatty acid synthesis and inflammation: FASN, SREBP1, CRP, and IL-6 in the HepG2 cell line. We observed lowered expression of FASN, SREBP1, CRP, and IL-6 in cells treated with 14-MPA in comparison with control cells. In contrast, supplementation with 12-MTA caused opposite effects: increased mRNA levels of FASN, CRP, and IL-6. 12-MTA did not influence SREBP1 expression. The results of our preliminary study may suggest potential benefits of the supplementation of iso-BCFAs in obese patients, for inflammation and hypertriglyceridemia prevention.

Association of branched-chain fatty acids with metabolic syndrome: a systematic review and meta-analysis of observational studies

Background: branched-chain fatty acids (BCFAs) have recently emerged as a group of functional fatty acids that are widely distributed in various foodstuffs, including dairy products, ruminant meat products, and fermented foods. Several studies have investigated the differences in the levels of BCFAs among individuals with varying risks of metabolic syndrome (MetS). In this study, we conducted a meta-analysis to explore the relationship between BCFAs and MetS, and to assess the feasibility of BCFAs as potential biomarkers for diagnosing MetS. Methods: in accordance with the PRISMA guidelines, we conducted a systematic literature search on PubMed, Embase, and the Cochrane Library up to March 2023. Both longitudinal and cross-sectional studies were included. The quality of the longitudinal and cross-sectional studies was evaluated using the Newcastle-Ottawa Scale (NOS) and the Agency for Healthcare Research and Quality (AHRQ) criteria, respectively. Heterogeneity detection and sensitivity analysis of the included research literature were carried out using R 4.2.1 software with a random-effects model. Results: Our meta-analysis included 685 participants and revealed a significant negative correlation between the endogenous BCFAs (serum BCFAs and adipose tissue BCFAs) and the risk of developing MetS, with lower BCFA levels found in individuals at a high risk of MetS (WMD: -0.11%, 95% CI: [-0.12, -0.09] %, P < 0.0001). However, there was no difference in fecal BCFAs among different MetS risk groups (SMD: -0.36, 95% CI: [-1.32, 0.61], P = 0.4686). Conclusion: our study provides insights into the relationship between BCFAs and the risk of developing MetS, and lays the groundwork for the development of novel biomarkers for diagnosing MetS in the future.

Monomethyl branched-chain fatty acids-a pearl dropped in the ocean

As an emerging group of bioactive fatty acids, monomethyl branched-chain fatty acids (mmBCFAs) have sparked the interest of many researchers both domestically and internationally. In addition to documenting the importance of mmBCFAs for growth and development, there is increasing evidence that mmBCFAs are highly correlated with obesity and insulin resistance. According to previous pharmacological investigations, mmBCFAs also exhibit anti-inflammatory effects and anticancer properties. This review summarized the distribution of mmBCFAs, which are widely found in dairy products, ruminants, fish, and fermented foods. Besides, we discuss the biosynthesis pathway in different species and detection methods of mmBCFAs. With the hope to unveil their mechanisms of action, we recapitulated detailed the nutrition and health benefits of mmBCFAs. Furthermore, this study provides a thorough, critical overview of the current state of the art, upcoming difficulties, and trends in mmBCFAs.

Monomethyl branched-chain fatty acids: Health effects and biological mechanisms

Branched-chain fatty acids (BCFA) are a group of lipids that are widely present in various organisms; they take part in numerous biochemical processes and affect multiple signaling pathways. However, BCFA are not well explored in terms of their effects on human health. Recently, they have been gaining interest, especially in relation to various human diseases. This review describes the occurrence of BCFA, their dietary sources, their potential health effects, and the current state of knowledge concerning their mechanism(s) of action. Many studies have been conducted so far in cellular and animal models, which reveal potent anti-cancer, lipid lowering, anti-inflammatory and neuroprotective actions. Research in humans is scarce. Therefore, further studies on animals and humans should be performed to confirm and expand these findings, and improve our understanding of the potential relevance of BCFA to human health and disease.

Comparative Proteomic Analysis Revealed the Mechanism of Tea Tree Oil Targeting Lipid Metabolism and Antioxidant System to Protect Hepatopancreatic Health in Macrobrachium rosenbergii

Tea tree oil (TTO) is a pure natural plant essential oil. The studies evaluated the hepatopancreas lipid metabolism and antioxidant efficacy of Macrobrachium rosenbergii fed with 0 (CT group) and 100 mg/kg TTO (TT group) by label-free quantification proteomic analysis. Compared to the CT group, the TT group improved growth performance and increased the survival rate after stress. Dietary TTO also decreased hemolymph AST and ALT activities and decreased hepatopancreatic vacuolation. At the same time, hepatopancreas lipids droplets and hemolymph lipids (TG, TC, LDL-C) were decreased, and the peroxidation products content (MDA, LPO, 4-HNE) was also decreased. In addition, the levels of hepatopancreas antioxidant enzymes (T-AOC, CAT, and SOD) were increased in the TT group. With proteomic analysis, a total of 151 differentially expressed proteins (DEPs) (99 up-regulated and 52 down-regulated) were identified in the hepatopancreas. Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction analysis showed that the 16 DEPs have interactions, which are mainly involved in the pathways related to lipid metabolism (fatty acid biosynthesis, fatty acid metabolism, glycerophospholipid metabolism) and redox reaction (cytochrome P450 enzyme systems). Furthermore, the mRNA expression of 15 proteins followed the proteomic analysis with qRT-PCR validation. Pearson correlation analysis showed that fatty acids and glycerophospholipid metabolism-related proteins were highly correlated to peroxide content, glycerophospholipid metabolism, and cytochrome P450 system-related proteins (CYP1A1, GSTT1, GPX4) were highly correlated to AST and ALT. Additionally, GPX4 is closely related to peroxide content and antioxidant enzyme activity. Our results revealed that TTO plays a protective role in the hepatopancreas targeting the critical enzymes and antioxidant reactions in lipid metabolism. Provides a new perspective to elucidate the action path of TTO in protecting invertebrate hepatopancreas, highlights the influence of lipid metabolism on hepatopancreas health and the interaction between lipid metabolism and antioxidant system in the regulation of TTO.

Towards engineered yeast as production platform for capsaicinoids

Capsaicinoids are bioactive alkaloids produced by the chili pepper fruit and are known to be the most potent agonists of the human pain receptor TRPV1 (Transient Receptor Potential Cation Channel Subfamily V Member 1). They are currently produced by extraction from chili pepper fruit or by chemical synthesis. Transfer of the biosynthetic route to a microbial host could enable more efficient capsaicinoid production by fermentation and may also enable the use of synthetic biology to create a diversity of new compounds with potentially improved properties. This review summarises the current state of the art on the biosynthesis of capsaicinoid precursors in baker's yeast, Saccharomyces cerevisiae, and discusses bioengineering strategies for achieving total synthesis from sugar.

Identification of Serum Metabolomics Characteristics in Patients with Stable Angina Pectoris Using UHPLC-QE-MS

Background

Stable angina pectoris (SAP) is one of the main types of coronary heart disease (CHD). To improve treatment outcomes, more effective biomarkers are needed. Currently, studies on the metabolic characteristics of SAP are lacking. Here, we explored the serum metabolomic profile of SAP and identified potential biomarkers and related pathways to assist the clinical diagnosis and treatment of SAP.

Method

Thirty patients with SAP patients and 30 healthy controls (CON) without stenosis were selected for this study. All patients underwent coronary angiography. The metabolites of the two groups' serum samples were investigated using UHPLC-QE-MS. Changes in serum metabolic profile were evaluated using multivariate statistical analysis and pathway analysis.

Result

OPLS-DA analysis identified significant differences in the serum metabolic profiles between patients with SAP and CON. Twenty-five differential metabolites were identified between patients from SAP and CON groups, including choline, creatine, L-arginine, beta-guanidinopropionic acid, isopalmitic acid, xanthine, LysoPC (18 : 1), and LysoPC (20 : 3). Pathway analysis found that these differential metabolites were involved in energy metabolism, oxidative stress, purine metabolism, and other metabolic pathways.

Conclusion

By comparing the serum metabolic profiles of SAP patients with a control group, we identified 25 potential biomarkers that could improve the clinical diagnosis and treatment of SAP.

Mechanisms Mediating the Regulation of Peroxisomal Fatty Acid Beta-Oxidation by PPARα

In mammalian cells, two cellular organelles, mitochondria and peroxisomes, share the ability to degrade fatty acid chains. Although each organelle harbors its own fatty acid β-oxidation pathway, a distinct mitochondrial system feeds the oxidative phosphorylation pathway for ATP synthesis. At the same time, the peroxisomal β-oxidation pathway participates in cellular thermogenesis. A scientific milestone in 1965 helped discover the hepatomegaly effect in rat liver by clofibrate, subsequently identified as a peroxisome proliferator in rodents and an activator of the peroxisomal fatty acid β-oxidation pathway. These peroxisome proliferators were later identified as activating ligands of Peroxisome Proliferator-Activated Receptor α (PPARα), cloned in 1990. The ligand-activated heterodimer PPARα/RXRα recognizes a DNA sequence, called PPRE (Peroxisome Proliferator Response Element), corresponding to two half-consensus hexanucleotide motifs, AGGTCA, separated by one nucleotide. Accordingly, the assembled complex containing PPRE/PPARα/RXRα/ligands/Coregulators controls the expression of the genes involved in liver peroxisomal fatty acid β-oxidation. This review mobilizes a considerable number of findings that discuss miscellaneous axes, covering the detailed expression pattern of PPARα in species and tissues, the lessons from several PPARα KO mouse models and the modulation of PPARα function by dietary micronutrients.

Novel Natural-based Biomolecules Discovery for Tackling Chronic Diseases

In the last decade, natural-derived/-based biomolecules have continuously played an important role in novel drug discovery (as a prototype drug template) for potential chronic disease treatment [...]