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Scientific Reports Jul 2023There is great interest on medium chain fatty acids (MCFA) for cardiovascular health. We explored the effects of MCFA on the expression of lipid metabolism and...
There is great interest on medium chain fatty acids (MCFA) for cardiovascular health. We explored the effects of MCFA on the expression of lipid metabolism and inflammatory genes in macrophages, and the extent to which they were mediated by the nuclear receptor peroxisome proliferator-activated receptor beta/delta (PPAR β/δ). J774A.1 murine macrophages were exposed to octanoate or decanoate as MCFA, a long-chain fatty acid control (palmitate), or the PPAR β/δ agonist GW501516, with or without lipopolysaccharide (LPS) stimulation, and with or without an siRNA-induced knockdown of PPAR β/δ. MCFA increased the expression of Plin2, encoding a lipid-droplet associated protein with anti-inflammatory effects in macrophages, in a partially PPAR β/δ-dependent manner. Both MCFA stimulated expression of the cholesterol efflux pump ABCA1, more pronouncedly under LPS stimulation and in the absence of PPAR β/δ. Octanoate stimulated the expression of Pltp, encoding a phospholipid transfer protein that aids ABCA1 in cellular lipid efflux. Only palmitate increased expression of the proinflammatory genes Il6, Tnf, Nos2 and Mmp9. Non-stimulated macrophages exposed to MCFA showed less internalization of fluorescently labeled lipoproteins. MCFA influenced the transcriptional responses of macrophages favoring cholesterol efflux and a less inflammatory response compared to palmitate. These effects were partially mediated by PPAR β/δ.
Topics: Mice; Animals; PPAR delta; PPAR-beta; Caprylates; Cell Line; Lipopolysaccharides; Macrophages; Fatty Acids; Cholesterol; Palmitates
PubMed: 37463952
DOI: 10.1038/s41598-023-38700-x -
Sheng Wu Gong Cheng Xue Bao = Chinese... Sep 2023In response to the market demand for therapeutic antibodies, the upstream cell culture scale and expression titer of antibodies have been significantly improved, while...
In response to the market demand for therapeutic antibodies, the upstream cell culture scale and expression titer of antibodies have been significantly improved, while the production efficiency of downstream purification process is relatively fall behind, and the downstream processing capacity has become a bottleneck limiting antibody production throughput. Using monoclonal antibody mab-X as experimental material, we optimized the caprylic acid (CA) precipitation process conditions of cell culture fluid and low pH virus inactivation pool, and studied two applications of using CA treatment to remove aggregates and to inactivate virus. Based on the lab scale study, we carried out a 500 L scale-up study, where CA was added to the low pH virus inactivation pool for precipitation, and the product quality and yield before and after precipitation were detected and compared. We found that CA precipitation significantly reduced HCP residuals and aggregates both before and after protein A affinity chromatography. In the aggregate spike study, CA precipitation removed about 15% of the aggregates. A virus reduction study showed complete clearance of a model retrovirus during CA precipitation of protein A purified antibody. In the scale-up study, the depth filtration harvesting, affinity chromatography, low pH virus inactivation, CA precipitation and depth filtration, and cation exchange chromatography successively carried out. The mixing time and stirring speed in the CA precipitation process significantly affected the CA precipitation effect. After CA precipitation, the HCP residue in the low pH virus inactivation solution decreased 895 times. After precipitation, the product purity and HCP residual meet the quality criteria of monoclonal antibodies. CA precipitation can reduce the chromatography step in the conventional purification process. In conclusion, CA precipitation in the downstream process can simplify the conventional purification process, fully meet the purification quality criterion of mab-X, and improve production efficiency and reduce production costs. The results of this study may promote the application of CA precipitation in the purification of monoclonal antibodies, and provide a reference for solving the bottleneck of the current purification process.
Topics: Cricetinae; Animals; Antibodies, Monoclonal; Caprylates; Cell Culture Techniques; Chromatography, Affinity; CHO Cells; Cricetulus; Chemical Precipitation
PubMed: 37805852
DOI: 10.13345/j.cjb.220882 -
Human Fertility (Cambridge, England) Dec 2023Alpha-lipoic acid (ALA) is a natural short chain fatty acid containing sulfhydryl groups generated from octanoic acid and cysteine in the mitochondria, and is found in... (Randomized Controlled Trial)
Randomized Controlled Trial
Alpha-lipoic acid (ALA) is a natural short chain fatty acid containing sulfhydryl groups generated from octanoic acid and cysteine in the mitochondria, and is found in both the aqueous and lipid phases. The present study aimed to assess the efficacy of ALA supplementation in primary infertile males complaining of idiopathic asthenozoospermia. Eighty patients were randomly allocated to treatment group A (n = 40) and control group B (n = 40) groups, receiving daily doses of 600 mg (divided into two daily doses of 300 mg each) of alpha lipoic acid (ALA) or an identical placebo for 90 days. Semen analysis, anthropometric and total antioxidant capacity were analysed and compared before and after treatment. Daily supplementation with ALA improved total motility and progressive motility of the spermatozoa. In the ALA-treated group, sperm motility and progressive motility increased significantly, similarly, the mean percentage of sperm vitality demonstrated a significant increase among the ALA treated group ( < 0.001). Analysis revealed a statistically significant increase in semen volume and sperm concentration in the ALA supplemented group, while abnormal morphology decreased significantly ( < 0.001). ALA supplementation significantly improved sperm parameters and functional tests in group A patients. ALA supplementation in patients with idiopathic asthenozoospermic thus enhanced sperm quality and viability, which could therefore be considered as an adjunct therapy pending further verification of its association and mechanisms involved.
Topics: Humans; Male; Thioctic Acid; Semen; Asthenozoospermia; Sperm Motility; Spermatozoa; Dietary Supplements
PubMed: 35023797
DOI: 10.1080/14647273.2021.2025271 -
Food & Function Oct 2023Medium-chain triglycerides (MCTs) are absorbed and metabolized more rapidly than long-chain triglycerides (LCTs) and therefore are considered to have obesity-prevention...
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. 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.
Topics: Mice; Animals; Diet, High-Fat; Molecular Docking Simulation; Triglycerides; Adipose Tissue; Liver; Mice, Inbred C57BL
PubMed: 37675852
DOI: 10.1039/d3fo01749d -
Drug Metabolism and Disposition: the... Jul 2023The emerging therapeutic modality of lipid nanoparticle (LNP)-encapsulated mRNAs has demonstrated promising clinical results when used as vaccines and is currently being...
Systemic Exposure, Metabolism, and Elimination of [C]-Labeled Amino Lipid, Lipid 5, after a Single Administration of mRNA Encapsulating Lipid Nanoparticles to Sprague-Dawley Rats.
The emerging therapeutic modality of lipid nanoparticle (LNP)-encapsulated mRNAs has demonstrated promising clinical results when used as vaccines and is currently being tested in formulations for a wide range of targeted chronic disease treatments. These therapeutics are multicomponent assemblages of well-characterized naturally occurring molecules in addition to xenobiotic molecules, whose in vivo distributions are poorly understood. Here, the metabolic outcome and in vivo elimination of heptadecan-9-yl 8-((2-hydroxyethyl) (8-(nonyloxy)-8-oxooctyl)amino)octanoate (Lipid 5), a key xenobiotic amino lipid in LNP formulations, were assessed after intravenous administration of C-labeled Lipid 5 to Sprague-Dawley rats. Intact Lipid 5 was predominantly cleared from plasma within 10 hour after dosing, with only small quantities (<1% of C dose) of a single diacid metabolite detected after 10 hour. Lipid 5 was rapidly metabolized via ester hydrolysis into aliphatic alcohols and diacidic amino head group moieties, which were further metabolized via -oxidation. Overall, >90% of the administered Lipid 5-derived C was recovered in urine (65%) and feces (35%), predominantly as oxidative metabolites, within 72 hour after dosing, indicating rapid renal and hepatic elimination. In vitro metabolite identification after incubation with human, nonhuman primate, and rat hepatocytes showed similar metabolites to those found in vivo. No meaningful differences were observed in Lipid 5 metabolism or elimination by sex. In conclusion, Lipid 5, a critical amino lipid component of LNPs for mRNA therapeutic delivery, showed minimal exposure, rapid metabolism, and near-complete elimination of C metabolites in rats. SIGNIFICANCE STATEMENT: Heptadecan-9-yl 8-((2-hydroxyethyl) (8-(nonyloxy)-8-oxooctyl)amino)octanoate (Lipid 5) is a key component of lipid nanoparticles used for the delivery of mRNA-based medicines; understanding the rates and routes of its clearance is crucial to assessing its long-term safety in lipid nanoparticle technology. This study conclusively established the rapid metabolism, and near-complete elimination of intravenously administered [C]Lipid 5 in rats via both liver and kidney as oxidative metabolites derived from ester hydrolysis and subsequent β-oxidation.
Topics: Rats; Humans; Animals; Rats, Sprague-Dawley; Caprylates; RNA, Messenger; Xenobiotics; Nanoparticles
PubMed: 37208185
DOI: 10.1124/dmd.122.001194 -
Shock (Augusta, Ga.) Mar 2024Background: Treatment of acute compartment syndrome (ACS)-induced skeletal muscle injury remains a challenge. Previous studies have shown that octanoic acid is a...
Background: Treatment of acute compartment syndrome (ACS)-induced skeletal muscle injury remains a challenge. Previous studies have shown that octanoic acid is a promising treatment for ACS owing to its potential ability to regulate metabolic/epigenetic pathways in ischemic injury. The present study was designed to investigate the efficacy and underlying mechanism of octanoic acid in ACS-induced skeletal muscle injury. Methods: In this study, we established a saline infusion ACS rat model. Subsequently, we assessed the protective effects of sodium octanoate (NaO, sodium salt of octanoic acid) on ACS-induced skeletal muscle injury. Afterward, the level of acetyl-coenzyme A and histone acetylation in the skeletal muscle tissue were quantified. Moreover, we investigated the activation of the AMP-activated protein kinas pathway and the occurrence of mitophagy in the skeletal muscle tissue. Lastly, we scrutinized the expression of proteins associated with mitochondrial dynamics in the skeletal muscle tissue. Results: The administration of NaO attenuated muscle inflammation, alleviating oxidative stress and muscle edema. Moreover, NaO treatment enhanced muscle blood perfusion, leading to the inhibition of apoptosis-related skeletal muscle cell death after ACS. In addition, NaO demonstrated the ability to halt skeletal muscle fibrosis and enhance the functional recovery of muscle post-ACS. Further analysis indicates that NaO treatment increases the acetyl-CoA level in muscle and the process of histone acetylation by acetyl-CoA. Lastly, we found NaO treatment exerts a stimulatory impact on the activation of the AMPK pathway, thus promoting mitophagy and improving mitochondrial dynamics. Conclusion: Our findings indicate that octanoic acid may ameliorate skeletal muscle injury induced by ACS. Its protective effects may be attributed to the promotion of acetyl-CoA synthesis and histone acetylation within the muscular tissue, as well as its activation of the AMPK-related mitophagy pathway.
Topics: Rats; Animals; Acetyl Coenzyme A; AMP-Activated Protein Kinases; Histones; Mitophagy; Muscle, Skeletal; Compartment Syndromes; Caprylates
PubMed: 38300834
DOI: 10.1097/SHK.0000000000002304 -
Toxicology Reports Dec 2023Perfluoro-alkyl substances (PFAS) are pollutants, whose exposure was associated with altered levels of low-density lipoproteins (LDL) in humans. Here we investigated...
Perfluoro-alkyl substances (PFAS) are pollutants, whose exposure was associated with altered levels of low-density lipoproteins (LDL) in humans. Here we investigated this clinical outcome in two groups of young male adults residing in areas of respectively low and high environmental exposure to perfluoro-octanoic-acid (PFOA). From the Regional Authority data on pollution areas, 38 not-exposed and 59 exposed age-matched participants were evaluated for serum levels of total cholesterol (Total-Chol), LDL-Chol, high-density lipoprotein cholesterol (HDL-Chol), triglycerides (Tgl) and chromatography quantified PFOA. Human hepato-carcinoma cell line HepG2 was exposed to PFOA or perfluoro-octane-sulfonate (PFOS), as legacy PFAAs, and C6O4 as new generation compound. Fluorimetry was used to evaluate the cell-uptake of labelled-LDL. Proprotein Convertase Subtilisin/Kexin 9 (PCSK9)-mediated LDL-receptor (LDL-R) degradation and sub-cellular localization of LDL-R were evaluated by western blot analysis. Serum levels of PFOA, were positively and significantly correlated with Total-Chol ( = 0.312, P = 0.002), LDL-Chol ( = 0.333, P = 0.001) and Tgl ( = 0.375, P < 0.001). Participants with high serum LDL-Chol and Tgl levels, according to the cardiovascular risk, were more prevalent in exposed compared to not-exposed subjects (respectively: 23.7% 5.3%, P = 0.023 and 18,6% 0%, P = 0.006). Exposure of HepG2 cells to PFOA or C6O4 100 ng/mL was associated with a significantly lower LDL uptake than controls but no major impact of any PFAAs on PCSK9-mediated LDL-R degradation was observed. Compared to controls, exposure to PFAS showed an unbalanced LDL-R partition between membrane and cytoplasm. Endocytosis inducer sphingosine restored LDL-R partition only in samples exposed to C6O4. These data suggest a novel endocytosis-based mechanism of altered lipid trafficking associated with the exposure to legacy PFAS.
PubMed: 37818225
DOI: 10.1016/j.toxrep.2023.09.016 -
Toxicology Dec 2023In humans, serum testosterone (T) is largely bound to the sex hormone binding globulin (SHBG) and human serum albumin (hSA), resulting in a 2-3 % of unbound or "free"...
In vitro binding analysis of legacy-linear and new generation-cyclic perfluoro-alkyl substances on sex hormone binding globulin and albumin, suggests low impact on serum hormone kinetics of testosterone.
In humans, serum testosterone (T) is largely bound to the sex hormone binding globulin (SHBG) and human serum albumin (hSA), resulting in a 2-3 % of unbound or "free" active quote (FT). Endocrine-disrupting chemicals, including perfluoro-alkyl substances (PFAS), are recognized to interfere with the hormonal axes, but the possible impact on the FT quote has not been addressed so far. Here we investigated the possible competition of two acknowledged PFAS molecules on T binding to SHBG and hSA. In particular, perfluoro-octanoic acid (PFOA) and acetic acid, 2,2-difluoro-2-((2,2,4,5-tetrafluoro-5(trifluoromethoxy)-1,3-dioxolan-4-yl)oxy)-ammonium salt (1:1) (C6O4) were used as, respectively, legacy-linear and new-generation-cyclic PFASs. Human recombinant SHBG 30-234 domain (SHBG), produced in HEK293-F cells, and delipidated recombinant hSA were used as in vitro protein models. Isothermal Titration Calorimetry (ITC) and tryptophan fluorescence quencing (TFQ) were used to evaluate the binding modes of T and PFAS to SHBG and hSA. ITC revealed the binding of T to SHBG with a K of 44 ± 2 nM whilst both PFOA and C6O4 showed no binding activity. Results were confirmed by TFQ, since only T modified the fluorescence profile of SHBG. In hSA, TFQ confirmed the binding of T on FA6 site of the protein. A similar binding mode was observed for PFOA but not for C6O4, as further verified by displacement experiments with T. Although both PFASs were previously shown to bind hSA, only PFOA is predicted to possibly compete with T for the binding to hSA. However, on the base of the binding stoichiometry and affinity of PFOA for hSA, this appears unlikely at the blood concentrations of the chemical documented to date.
Topics: Humans; Fluorocarbons; HEK293 Cells; Protein Binding; Serum Albumin, Human; Sex Hormone-Binding Globulin; Testosterone; Tryptophan
PubMed: 37931871
DOI: 10.1016/j.tox.2023.153664 -
Biomolecules Jan 2024Third-degree burn injuries pose a significant health threat. Safer, easier-to-use, and more effective techniques are urgently needed for their treatment. We hypothesized...
Development of a Novel Covalently Bonded Conjugate of Caprylic Acid Tripeptide (Isoleucine-Leucine-Aspartic Acid) for Wound-Compatible and Injectable Hydrogel to Accelerate Healing.
Third-degree burn injuries pose a significant health threat. Safer, easier-to-use, and more effective techniques are urgently needed for their treatment. We hypothesized that covalently bonded conjugates of fatty acids and tripeptides can form wound-compatible hydrogels that can accelerate healing. We first designed conjugated structures as fatty acid-aminoacid1-amonoacid2-aspartate amphiphiles (Cn acid-AA1-AA2-D), which were potentially capable of self-assembling into hydrogels according to the structure and properties of each moiety. We then generated 14 novel conjugates based on this design by using two Fmoc/tBu solid-phase peptide synthesis techniques; we verified their structures and purities through liquid chromatography with tandem mass spectrometry and nuclear magnetic resonance spectroscopy. Of them, 13 conjugates formed hydrogels at low concentrations (≥0.25% /), but C8 acid-ILD-NH showed the best hydrogelation and was investigated further. Scanning electron microscopy revealed that C8 acid-ILD-NH formed fibrous network structures and rapidly formed hydrogels that were stable in phosphate-buffered saline (pH 2-8, 37 °C), a typical pathophysiological condition. Injection and rheological studies revealed that the hydrogels manifested important wound treatment properties, including injectability, shear thinning, rapid re-gelation, and wound-compatible mechanics (e.g., moduli G″ and G', ~0.5-15 kPa). The C8 acid-ILD-NH() hydrogel markedly accelerated the healing of third-degree burn wounds on mice. Taken together, our findings demonstrated the potential of the Cn fatty acid-AA1-AA2-D molecular template to form hydrogels capable of promoting the wound healing of third-degree burns.
Topics: Mice; Animals; Mice, Inbred C57BL; Caprylates; Aspartic Acid; Isoleucine; Leucine; Hydrogels; Fatty Acids; Wound Healing
PubMed: 38254694
DOI: 10.3390/biom14010094 -
Journal of Oleo Science 2024Unsaturated fatty acids, such as oleic and linoleic acids, are easily oxidized by exposure to temperature and light in the presence of air to form unsaturated fatty acid... (Comparative Study)
Comparative Study
Unsaturated fatty acids, such as oleic and linoleic acids, are easily oxidized by exposure to temperature and light in the presence of air to form unsaturated fatty acid hydroperoxides as primary oxidation products. However, the catabolic rates of unsaturated fatty acid hydroperoxides in the human body remain unknown. In this study, ethyl esters of C-labeled linoleic acid (*C18:2-EE) and oleic acid (*C18:1-EE) and their hydroperoxides (*C18:2-EE-OOH and *C18:1-EE-OOH, respectively) prepared by the photo-oxidation of *C18:2-EE and *C18:1-EE, respectively, were administered to mice and their catabolic rates were determined by measuring the expired CO levels. *C18:2-EE-OOH and *C18:1-EE-OOH were β-oxidized faster than *C18:2-EE and *C18:1-EE, respectively. Notably, rapid β-oxidation of *C18:2-EE-OOH and *C18:1-EE-OOH was similar to that of medium-chain fatty acids, such as octanoic acid. Then, degradation products of C18:2-EE-OOH and C18:1-EE-OOH were analyzed under gastric conditions by gas chromatography/mass spectrometry. Major decomposition products of C18:2-EE-OOH and C18:1-EE-OOH were medium-chain compounds, such as octanoic acid ethyl ester, 9-oxo-nonanoic acid ethyl ester, and 10-oxo-8-decenoic acid ethyl esters, indicating that C18:2-EE-OOH and C18:1-EE-OOH isomers formed during photo-oxidation were decomposed under acidic conditions. These findings support previous reports that dietary lipid hydroperoxides are not absorbed into the intestine as lipid hydroperoxides but as degradation products. This is the first study to suggest that dietary lipid hydroperoxides decompose during gastric digestion to form medium-chain compounds that are directly absorbed into the liver via the portal vein and rapidly catabolized via β-oxidation.
Topics: Animals; Oxidation-Reduction; Oleic Acid; Linoleic Acid; Carbon Dioxide; Carbon Isotopes; Mice; Male; Hydrogen Peroxide
PubMed: 38825538
DOI: 10.5650/jos.ess23236