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Biological & Pharmaceutical Bulletin 2021Long-chain acyl-CoA synthetases (ACSLs) are a family of enzymes that convert long-chain free fatty acids into their active form, acyl-CoAs. Recent knock-out mouse...
Long-chain acyl-CoA synthetases (ACSLs) are a family of enzymes that convert long-chain free fatty acids into their active form, acyl-CoAs. Recent knock-out mouse studies revealed that among ACSL isoenzymes, ACSL6 plays an important role in the maintenance of docosahexaenoic acid (DHA)-containing glycerophospholipids. Several transcript variants of the human ACSL6 gene have been found; the two major ACSL6 variants, ACSL6V1 and V2, encode slightly different short motifs that both contain a conserved structural domain, the fatty acid Gate domain. In the present study, we expressed recombinant human ACSL6V1 and V2 in Spodoptera frugiperda 9 (Sf9) cells using the baculovirus expression system, and then, using our novel ACSL assay system with liquid chromatography-tandem mass spectrometry (LC-MS/MS), we examined the substrate specificities of the recombinant human ACSL6V1 and V2 proteins. The results showed that both ACSL6V1 and V2 could convert various kinds of long-chain fatty acids into their acyl-CoAs. Oleic acid was a good common substrate and eicosapolyenoic acids were poor common substrates for both variants. However, ACSL6V1 and V2 differed considerably in their preferences for octadecapolyenoic acids, such as linoleic acid, and docosapolyenoic acids, such as DHA and docosapentaenoic acid (DPA): ACSL6V1 preferred octadecapolyenoic acids, whereas V2 strongly preferred docosapolyenoic acids. Moreover, our kinetic studies revealed that ACSL6V2 had a much higher affinity for DHA than ACSL6V1. Our results suggested that ACSL6V1 and V2 might exert different physiological functions and indicated that ACSL6V2 might be critical for the maintenance of membrane phospholipids bearing docosapolyenoic acids such as DHA.
Topics: Animals; Coenzyme A Ligases; Docosahexaenoic Acids; Enzyme Assays; Humans; Isoenzymes; Kinetics; Linoleic Acid; Phospholipids; Recombinant Proteins; Sf9 Cells; Spodoptera; Stearic Acids; Substrate Specificity; Tandem Mass Spectrometry
PubMed: 34602568
DOI: 10.1248/bpb.b21-00551 -
Bone Reports Dec 2021The osteoclast-dependent bone resorption process is a crucial part of the bone regulatory system. The excessive function of osteoclasts can cause diseases of bone,...
The osteoclast-dependent bone resorption process is a crucial part of the bone regulatory system. The excessive function of osteoclasts can cause diseases of bone, joint, and other tissues such as osteoporosis and osteoarthritis. Greenshell mussel oil (GSM), a good source of long chain omega-3 polyunsaturated fatty acids (LCn-3PUFAs), was fractionated into total lipid, polar lipid, and non-polar lipid components and their anti-osteoclastogenic activity tested in RAW 264.7 cell cultures. Osteoclast differentiation process was achieved after 5 days of incubation with RANKL in 24-well culture plates. Introducing the non-polar lipid fraction into the culture caused a lack of cell differentiation, and a reduction in tartrate-resistant acid phosphatase (TRAP) activity and TRAP cell numbers in a dose-dependent manner (50% reduction at the concentration of 20 μg/mL, p < 0.001). Moreover, actin ring formation was significantly diminished by non-polar lipids at 10-20 μg/mL. The bone digestive enzymes released by osteoclasts into the pit formation were also compromised by downregulating gene expression of cathepsin K, carbonic anhydrase II (CA II), matrix metalloproteinase 9 (MMP-9), and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1). This study revealed that the non-polar lipid fraction of GSM oil contains bioactive substances which possess potent anti-osteoclastogenic activity.
PubMed: 34632003
DOI: 10.1016/j.bonr.2021.101132 -
Marine Drugs Jan 2019The marine thraustochytrids are a promising source of docosahexaenoic acid (DHA) and the ketocarotenoid astaxanthin. In this study, the biosynthetic pathways of these...
The marine thraustochytrids are a promising source of docosahexaenoic acid (DHA) and the ketocarotenoid astaxanthin. In this study, the biosynthetic pathways of these two important metabolites in sp. SK4 was illustrated by the analyses of the genome, transcriptome, key enzymes, and pathway products. Two sets of genes were involved in two pathways for the biosynthesis of fatty acids. The absence of genes and the presence of docosapentaenoic acid (DPA), up to 12% of total fatty acids suggest that sp. SK4 may synthesize DHA mainly via a polyketide synthase (PKS) pathway. Three enzymes, namely geranyl diphosphate synthase (GPPS), farnysyl diphosphate synthase (FPPS), and geranylgeranyle diphosphate synthase (GGPPS) were found to be involved in the formation of GGPP that was subsequently catalyzed to β-carotene by a trifunctional CrtIBY enzyme. β-Carotene might be ketolated and then hydroxylated into astaxanthin based on the carotenoid profiles. The formation of GGPP was proposed to be the limiting steps for carotenoid production. Overexpression of the GPS together with the isopentenyl pyrophosphate isomerase, and hemoglobin resulted in not only 1.85- and 5.02-fold increases of total carotenoids and astaxanthin, but also 2.40- and 2.74-fold increases of total fatty acids and DHA. This study provides insights into the biosynthesis of carotenoids and fatty acids in .
Topics: Docosahexaenoic Acids; Eukaryota; Genome; Metabolic Engineering; Transcriptome; Xanthophylls
PubMed: 30634667
DOI: 10.3390/md17010045 -
Bioscience, Biotechnology, and... Oct 2008To investigate the metabolism and distribution of docosapentaenoic acid (22:5n-6, DPA) in the liver and testis of growing rats, 22:5n-6 was administered to their dams....
To investigate the metabolism and distribution of docosapentaenoic acid (22:5n-6, DPA) in the liver and testis of growing rats, 22:5n-6 was administered to their dams. Newborn rats with a low hepatic arachidonic acid (20:4n-6, AA) level were generated by administrating a diet rich in docosahexaenoic acid (22:6n-3, DHA) but n-6 fatty acid (FA) free to pregnant dams. After parturition, 22:5n-6 or linoleic acid (18:2n-6, LA) was administered with a high level of 22:6n-3 to the dams until weaning. At weaning, the hepatic 20:4n-6 level was significantly highest in the DPA-DHA but not LA-DHA diet-fed animals. The hepatic delta-6 desaturase (D6D) mRNA abundance was significantly lower in both the LA-DHA and DPA-DHA diet-fed animals, connoted with the 20:4n-6 content recovered by 22:5n-6 that did not involve D6D and supporting the occurrence of retroconversion in the liver of the growing rats. The low D6D level in the 3-week-old testis was not in proportion to the elevated 22:5n-6 level, implying that early testicular 22:5n-6 accumulation might require supply from the circulation system.
Topics: Animal Feed; Animals; Fatty Acids, Unsaturated; Female; Gene Expression Regulation, Enzymologic; Linoleoyl-CoA Desaturase; Liver; Male; Milk; Organ Size; RNA, Messenger; Rats; Testis
PubMed: 18838818
DOI: 10.1271/bbb.80249 -
Molecular Medicine Reports Sep 2022Ulcerative colitis (UC) is difficult to eradicate as it leads to chronic inflammation in the digestive tract due to immune system malfunction. The present study...
Ulcerative colitis (UC) is difficult to eradicate as it leads to chronic inflammation in the digestive tract due to immune system malfunction. The present study demonstrated the protective effect of 7S,15R‑dihydroxy‑16S,17S‑epoxy‑docosapentaenoic acid (diHEP‑DPA), which had been previously synthesized, on a dextran sulfate sodium (DSS)‑induced BALB/c mouse model of UC. UC was induced with 4% DSS drinking water for 7 days. Initially, the anti‑inflammatory effect of diHEP‑DPA was confirmed by demonstrating that lipopolysaccharide‑stimulated THP1 cells treated with diHEP‑DPA decreased IL‑6, TNF‑α and nitrite levels by fluorescence‑activated cell sorting (FACS) and Griess reagent kit. The results indicated that the administration of diHEP‑DPA at 20 µg/kg significantly reduced the severity of colitis, as determined by hematoxylin and eosin staining. The levels of TNF‑α, IL‑6 and IL‑1β in the colon tissue and serum were significantly reduced in the diHEP‑DPA + DSS‑treated group compared with in the control group, as determined by FACS and ELISA kit. It was also observed that diHEP‑DPA decreased myeloperoxidase (MPO) and nitrite levels in the colon tissues of diHEP‑DPA + DSS‑treated mice, as indicated using commercial MPO and nitric oxide kits. The diHEP‑DPA+DSS‑treated mice also exhibited decreased expression levels of phosporylated (p)‑inhibitor κB protein, p‑p65 and inducible nitric oxide synthase in the colon tissue by inhibiting inflammation, which were measured by reverse transcription‑quantitative PCR and weatern blot analysis. Overall, the present study demonstrated the protective effect of diHEP‑DPA against a severe colitis condition .
Topics: Animals; Colitis; Colitis, Ulcerative; Colon; Dextran Sulfate; Disease Models, Animal; Fatty Acids, Unsaturated; Inflammation; Interleukin-6; Mice; Mice, Inbred BALB C; NF-kappa B; Nitrites; Tumor Necrosis Factor-alpha
PubMed: 35856414
DOI: 10.3892/mmr.2022.12794 -
The Chinese Journal of Physiology 2023Regular moderate physical exercise is beneficial for the cardiovascular system. Our prior study has demonstrated a long-term moderate exercise (4-week of 60-min 74.0%...
Regular moderate physical exercise is beneficial for the cardiovascular system. Our prior study has demonstrated a long-term moderate exercise (4-week of 60-min 74.0% V̇O treadmill running) is optimal in protecting from exhaustive exercise-induced cardiac ischemic injury. This study is aimed to investigate the effect of long-term moderate exercise on myocardial metabolome in rats. Thirteen male Sprague-Dawley rats were randomly assigned into the control group (C) and the long-term moderate exercise group (E). The targeted metabolomics of the myocardium was analyzed by ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) system. Results showed that the metabolites categories of bile acids (BAs), fatty acids (FAs), and phenylpropanoic acids were significantly decreased. The biosynthesis of unsaturated FAs pathway was significantly downregulated. The altered metabolites in the E Group included decreased FAs (pentadecanoic acid, 10Z-heptadecenoic acid, dihomo-gamma-linolenic acid, docosahexaenoic acid, docosapentaenoic acid, and 10Z-nonadecenoic acid), decreased BAs (chenodeoxycholic acid and beta-muricholic acid), decreased organic acids (glycolic acid and 2-hydroxyglutaric acid), decreased carbohydrate (N-acetylneuraminic acid, Neu5Ac), decreased amino acids (α-aminobutyric acid and norvaline), decreased phenylpropanoic acids (hydroxyphenyllactic acid), and benzoic acids (4-hydroxybenzoic acid and phthalic acid). The results indicated that long-term moderate exercise has promoted lipids utilization in myocardium while exerted little influence on carbohydrate metabolism and diminished many detrimental metabolites. Notably, decrease of myocardial carbohydrate Neu5Ac after long-term moderate exercise might predict a prospective metabolomics biomarker for cardioprotection. This research has displayed the effect of long-term moderate exercise on myocardial metabolomic profiling in rats and indicated some promising metabolites which can be applied for exercise benefits in future.
Topics: Rats; Male; Animals; Rats, Sprague-Dawley; Chromatography, Liquid; Prospective Studies; Tandem Mass Spectrometry; Metabolome; Myocardium; Carbohydrates
PubMed: 38149568
DOI: 10.4103/cjop.CJOP-D-23-00126 -
Biochimica Et Biophysica Acta Sep 2016Whole body docosahexaenoic acid (DHA, 22:6n-3) synthesis from α-linolenic acid (ALA, 18:3n-3) is considered to be very low, however, the daily synthesis-secretion of...
Whole body docosahexaenoic acid (DHA, 22:6n-3) synthesis from α-linolenic acid (ALA, 18:3n-3) is considered to be very low, however, the daily synthesis-secretion of DHA may be sufficient to supply the adult brain. The current study aims to assess whether whole body DHA synthesis-secretion kinetics are different when comparing plasma ALA versus eicosapentaenoic acid (EPA, 20:5n-3) as the precursor. Male Long Evans rats (n=6) were fed a 2% ALA in total fat diet for eight weeks, followed by surgery to implant a catheter into each of the jugular vein and carotid artery and 3h of steady-state infusion with a known amount of (2)H-ALA and (13)C-eicosapentaenoic acid (EPA, 20:5n3). Blood samples were collected at thirty-minute intervals and plasma enrichment of (2)H- and (13)C EPA, n-3 docosapentaenoic acid (DPAn-3, 22:5n-3) and DHA were determined for assessment of synthesis-secretion kinetic parameters. Results indicate a 13-fold higher synthesis-secretion coefficient for DHA from EPA as compared to ALA. However, after correcting for the 6.6 fold higher endogenous plasma ALA concentration, no significant differences in daily synthesis-secretion (nmol/day) of DHA (97.6±28.2 and 172±62), DPAn-3 (853±279 and 1139±484) or EPA (1587±592 and 1628±366) were observed from plasma unesterified ALA and EPA sources, respectively. These results suggest that typical diets which are significantly higher in ALA compared to EPA yield similar daily DHA synthesis-secretion despite a significantly higher synthesis-secretion coefficient from EPA.
Topics: Animals; Docosahexaenoic Acids; Eicosapentaenoic Acid; Kinetics; Male; Rats; Rats, Long-Evans; alpha-Linolenic Acid
PubMed: 27263420
DOI: 10.1016/j.bbalip.2016.05.014 -
Nutrients Aug 2015The role of the long-chain omega-3 (n-3) fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in lipid metabolism and inflammation has been extensively... (Randomized Controlled Trial)
Randomized Controlled Trial
Red Blood Cell Docosapentaenoic Acid (DPA n-3) is Inversely Associated with Triglycerides and C-reactive Protein (CRP) in Healthy Adults and Dose-Dependently Increases Following n-3 Fatty Acid Supplementation.
The role of the long-chain omega-3 (n-3) fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in lipid metabolism and inflammation has been extensively studied; however, little is known about the relationship between docosapentaenoic acid (DPA, 22:5 n-3) and inflammation and triglycerides (TG). We evaluated whether n-3 DPA content of red blood cells (RBC) was associated with markers of inflammation (interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and C-reactive protein (CRP) and fasting TG prior to n-3 supplementation in two studies (Study 1: n = 115, aged 20-44 years, body mass index (BMI) 20-30 kg/m2, TG = 34-176 mg/dL; Study 2: n = 28, aged 22-65 years, BMI 24-37 kg/m2, TG = 141-339 mg/dL). We also characterized the dose-response effects of n-3 fatty acid supplementation on RBC n-3 DPA after five months of supplementation with fish oil (Study 1: 0, 300, 600, 900, and 1800 mg/day EPA + DHA) and eight weeks of prescription n-3 ethyl esters (Study 2: 0, 850, and 3400 mg/day EPA + DHA). In Study 1, RBC n-3 DPA was inversely correlated with CRP (R2 = 36%, p < 0.001) and with fasting TG (r = -0.30, p = 0.001). The latter finding was replicated in Study 2 (r = -0.33, p = 0.04). In both studies, n-3 supplementation significantly increased RBC n-3 DPA dose-dependently. Relative increases were greater for Study 1, with increases of 29%-61% vs. 14%-26% for Study 2. The associations between RBC n-3 DPA, CRP, and fasting TG may have important implications for the prevention of atherosclerosis and chronic inflammatory diseases and warrant further study.
Topics: Adult; Aged; Biomarkers; Body Mass Index; C-Reactive Protein; Cross-Over Studies; Dietary Supplements; Dose-Response Relationship, Drug; Eicosapentaenoic Acid; Erythrocytes; Fatty Acids, Omega-3; Fatty Acids, Unsaturated; Female; Fish Oils; Humans; Interleukin-6; Lipid Metabolism; Male; Middle Aged; Triglycerides; Tumor Necrosis Factor-alpha; Young Adult
PubMed: 26247967
DOI: 10.3390/nu7085291 -
Prostaglandins, Leukotrienes, and... Jun 2021Omega-3 fatty acids have been suggested as a complement in cancer treatment, but doses are not established. We performed a dose-finding study in 33 children in remission... (Clinical Trial)
Clinical Trial
Omega-3 fatty acids have been suggested as a complement in cancer treatment, but doses are not established. We performed a dose-finding study in 33 children in remission from cancer. Participants were allocated to a body surface area (BSA) adjusted dose (mg/m) of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (40:60), ranging 233-3448 mg/m daily for 90 days. Fatty acid concentration in plasma phospholipids and red blood cells were determined by GC. Supplementation was well tolerated and correlated strongly with blood ω3-fatty acid concentrations and EPA showed the highest increase. Using the ω3-index disregards docosapentaenoic acid (DPA), which increased 30-43% in our study motivating an EDD-index (∑EPA,DPA,DHA). The ratio between arachidonic acid and EPA or DHA showed negative exponential trends. Dose per BSA enabled an individualized omega-3 supplementation decreasing the variation referred to interindividual differences. Based on our results, we suggest a dose of 1500 mg/m BSA for further studies.
Topics: Adolescent; Body Surface Area; Child; Child, Preschool; Chromatography, Gas; Docosahexaenoic Acids; Drug Administration Schedule; Drug Dosage Calculations; Eicosapentaenoic Acid; Fatty Acids, Omega-3; Female; Humans; Male; Neoplasms
PubMed: 33964665
DOI: 10.1016/j.plefa.2021.102285