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Plastic products and nutrients are widely used in aquaculture facilities, resulting in copresence of nanoplastics (NPs) released from plastics and microcystins (MCs) from toxic cyanobacteria. The potential effects of NPs-MCs coexposure on aquatic products require investigation. This study investigated the toxic effects of polystyrene (PS) NPs and MC-LR on the gut-liver axis of silver carp Hypophthalmichthys molitrix, a representative commercial fish, and explored the effects of the coexposure on intestinal microorganism structure and liver metabolic function using traditional toxicology and multi-omics association analysis. The results showed that the PS-NPs and MC-LR coexposure significantly shortened villi length, and the higher the concentration of PS-NPs, the more obvious the villi shortening. The coexposure of high concentrations of PS-NPs and MC-LR increased the hepatocyte space in fish, and caused obvious loss of gill filaments. The diversity and richness of the fish gut microbes significantly increased after the PS-NPs exposure, and this trend was amplified in the copresence of MC-LR. In the coexposure, MC-LR contributed more to the alteration of fish liver metabolism, which affected the enrichment pathway in glycerophospholipid metabolism and folic acid biosynthesis, and there was a correlation between the differential glycerophospholipid metabolites and affected bacteria. These results suggested that the toxic mechanism of PS-NPs and MC-LR coexposure may be pathological changes of the liver, gut, and gill tissues, intestinal microbiota disturbance, and glycerophospholipid metabolism imbalance. The findings not only improve the understanding of environmental risks of NPs combined with other pollutants, but also provide potential microbiota and glycerophospholipid biomarkers in silver carp., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Tetrabromobisphenol A (TBBPA) and tetrabromobisphenol S (TBBPS) are widely distributed brominated flame retardants. While TBBPA has been demonstrated to stimulate adipogenesis, TBBPS is also under suspicion for potentially inducing comparable effects. In this study, we conducted a non-targeted metabolomics to examine the metabolic changes in 3T3-L1 cells exposed to an environmentally relevant dose of TBBPA or TBBPS. Our findings revealed that 0.1 µM of both TBBPA and TBBPS promoted the adipogenesis of 3T3-L1 preadipocytes. Multivariate analysis showed significant increases in glycerophospholipids, sphingolipids, and steroids relative levels in 3T3-L1 cells exposed to TBBPA or TBBPS at the final stage of preadipocyte differentiation. Metabolites set composed of glycerophospholipids was found to be highly effective predictors of adipogenesis in 3T3-L1 cells exposed to TBBPA or TBBPS (revealed from the receiver operating characteristic curve with an area under curve > 0.90). The results from metabolite set enrichment analysis suggested both TBBPA and TBBPS exposures significantly perturbed steroid biosynthesis in adipocytes. Moreover, TBBPS additionally disrupted the sphingolipid metabolism in the adipocytes. Our study presents new insights into the obesogenic effects of TBBPS and provides valuable information about the metabolites associated with adipogenesis induced by TBBPA or TBBPS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Bisphenols are known as endocrine disruptor that affect the development, and growth of marine creatures, including human. There were plenty of manuscripts evaluated the toxicology of bisphenol A (BPA) and its analogues such as bisphenol F (BPF), bisphenol AF (BPAF), and bisphenol S (BPS), but limits of them studied the effects of bisphenol analogues on echinoderms. In this study, we used metabolomics to investigate the metabolic response of sea cucumber (Apostichopus japonicus) exposed to BPAF, and the activities of glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) were determined. The results demonstrated alterations in lipid metabolism, glycerophospholipid metabolism, and biosynthesis of amino acids following BPAF treatment. Sea cucumbers upregulated the glycerophospholipid metabolism to repair the destruction of intestine cellular homeostasis. Six metabolites were selected as the potential biomarkers for the exposure of BPAF. This study revealed the metabolic response and oxidative response of sea cucumber arising from BPAF exposure, and provided theoretical support for the risk assessment of bisphenol analogues on economically important echinoderms, such as A. japonicus., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Milk fat globules (MFGs) surround the triacylglycerol core that composes milk fat. The aim of this study is to induce milk fat depression via dietary conjugated linoleic acid (CLA) supplementation to study MFG size parameters, number and glycerophospholipid composition. Eighteen Holstein dairy cows (136 ± 28 days in milk, 571 ± 37.9 kg body weight, 27.6 ± 2.1 kg milk/day) were selected and randomly assigned to a control or CLA group for a 14-day period. Cows were fed a basal diet (control, n = 8) or the control plus 400 g/day CLA (C18:2 cis-9, trans-11 38.1% and C18:2 trans-10, cis-12 36.8%) (n = 10) for 7 days after which the CLA group was switched to the basal diet for another 7 days along with the control group. Cow performance, milk composition, MFG size and numbers were measured daily. On the seventh day after the start of the experiment, milk samples were identified and the quantification of glycerophospholipid compounds, and RNA were isolated from milk fat samples for a real-time polymerase chain reaction. Compared with control, at Day 7 from the start of feeding, supplemental CLA did not affect milk production (28.09 vs. 28.50 kg/day), dry matter intake (14.9 vs. 15.4 kg/day), or milk protein (3.55/100 vs. 3.70 g/100 ml) and lactose contents (5.11/100 vs. 5.17 g/100 ml). However, although the specific surface area of MFG (2138 vs. 1815 m²/kg) was greater, CLA reduced milk fat content (1.95/100 vs 3.64 g/100 ml on Day 7) and particle size parameters of MFG. The number of MFG gradually decreased until Day 7 of feeding, and then increased by Day 14 (2.96 × 10 9 on Day 1, 1.63 × 10 9 on Day 7 and 2.28 × 10 9 on Day 14) in the CLA group. Compared with control, glycerophospholipid analysis revealed that concentrations of phosphatidylcholine (PC) (e.g., PC [16:0/18:1] 20322 vs. 29793 nmol/L), lysophosphatidylethanolamine (LPE) (e.g., LPE [18:1] 956 vs. 4610 nmol/L) and phosphatidylethanolamine (PE) (e.g., PE [16:0/18:1] 7000 vs. 9769 nmol/L) in milk lipids decreased during CLA feeding. In contrast, concentrations of phosphatidylinositol (PI) (e.g., PI [18:0/18:1] 4052 vs. 1799 nmol/L) and phosphatidylserine (PS) (e.g., PS [18:1/18:2] 9500 vs. 6843 nmol/L) increased. The messenger RNA abundance of fatty acid synthase, diacylglycerol O-acyltransferase 1, glycerol-3-phosphate acyltransferase 4 and phosphate cytidylyltransferase 1, choline, alpha (PCYT1A) were downregulated in the CLA group, confirming published data demonstrating a negative effect of CLA on lipogenesis in the mammary gland. Overall, these results provided evidence for the important role of lipogenic gene expression in the regulation of MFG size, number and glycerophospholipid composition., (© 2022 Wiley-VCH GmbH.)

Objective: Recent investigations have demonstrated that Polygonum perfoliatum L. can protect against chemical liver injury, but the mechanism behind its efficacy is still unclear. Therefore, we studied the pharmacological mechanism at work in P. perfoliatum protection against chemical liver injury., Methods: To evaluate the activity of P. perfoliatum against chemical liver injury, levels of alanine transaminase, lactic dehydrogenase, aspartate transaminase, superoxide dismutase, glutathione peroxidase and malondialdehyde were measured, alongside histological assessments of the liver, heart and kidney tissue. A nontargeted lipidomics strategy based on ultra-performance liquid chromatography quadrupole-orbitrap high-resolution mass spectrometry method was used to obtain the lipid profiles of mice with chemical liver injury and following treatment with P. perfoliatum; these profiles were used to understand the possible mechanisms behind P. perfoliatum's protective activity., Results: Lipidomic studies indicated that P. perfoliatum protected against chemical liver injury, and the results were consistent between histological and physiological analyses. By comparing the profiles of liver lipids in model and control mice, we found that the levels of 89 lipids were significantly changed. In animals receiving P. perfoliatum treatment, the levels of 8 lipids were significantly improved, relative to the model animals. The results showed that P. perfoliatum extract could effectively reverse the chemical liver injury and significantly improve the abnormal liver lipid metabolism of mice with chemical liver injury, especially glycerophospholipid metabolism., Conclusion: Regulation of enzyme activity related to the glycerophospholipid metabolism pathway may be involved in the mechanism of P. perfoliatum's protection against liver injury. Please cite this article as: Peng L, Chen HG, Zhou X. Lipidomic investigation of the protective effects of Polygonum perfoliatum against chemical liver injury in mice. J Integr Med. 2023; 21(3): 289-301., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Shanghai Changhai Hospital. Published by Elsevier B.V. All rights reserved.)

This research aimed to explore the protective effect of quercetin against nephrotoxicity induced by four organophosphate pesticide mixtures (PM) using untargeted metabolomics technology in rat kidneys. Sixty male Wistar rats were randomly divided into six groups: control, low-dose quercetin treated (10 mg/kg bw), high-dose quercetin treated (50 mg/kg bw), PM-treated, and two dosages of quercetin + PM-treated. Metabolomics results showed that 17 differential metabolites were identified in the PM-treated group, and pathway analysis revealed that renal metabolic disorders include purine metabolism, glycerophospholipid metabolism, and vitamin B6 metabolism. When high-dose quercetin and PM-treated were administered to rats concurrently, the intensities of differential metabolites were substantially restored (p < 0.01), suggesting that quercetin can improve renal metabolic disorders caused by organophosphate pesticides (OPs). Mechanistically, quercetin could regulate the purine metabolism disorder and endoplasmic reticulum stress (ERS)-mediated autophagy induced by OPs by inhibiting XOD activity. Moreover, quercetin inhibits PLA2 activity to regulate glycerophospholipid metabolism and it could also exert antioxidant and anti-inflammatory effects to correct vitamin B6 metabolism in rat kidneys. Taken together, the high dose of quercetin (50 mg/kg. bw) has a certain protective effect on OPs-induced nephrotoxicity in rats, which provides a theoretical basis for quercetin against nephrotoxicity caused by OPs., Competing Interests: Declaration of competing interest The authors have no competing financial interests that could have appeared to influence this work to declare., (Copyright © 2023. Published by Elsevier Ltd.)

Based on the multiomics analysis, this study is aimed at investigating the underlying mechanism of didymin against acute liver injury (ALI). The mice were administrated with didymin for 2 weeks, followed by injection with lipopolysaccharide (LPS) plus D-galactosamine (D-Gal) to induce ALI. The pathological examination revealed that didymin significantly ameliorated LPS/D-Gal-induced hepatic damage. Also, it markedly reduced proinflammatory cytokines release by inhibiting the TLR4/NF- κ B pathway activation, alleviating inflammatory injury. A transcriptome analysis proved 2680 differently expressed genes (DEGs) between the model and didymin groups and suggested that the PI3K/Akt and metabolic pathways might be the most relevant targets. Meanwhile, the metabolome analysis revealed 67 differently expressed metabolites (DEMs) between the didymin and model groups that were mainly clustered into the glycerophospholipid metabolism, which was consistent with the transcriptome study. Importantly, a comprehensive analysis of both the omics indicated a strong correlation between the DEGs and DEMs, and an in-depth study demonstrated that didymin alleviated metabolic disorder and hepatocyte injury likely by inhibiting the glycerophospholipid metabolism pathway through the regulation of PLA2G4B, LPCAT3, and CEPT1 expression. In conclusion, this study demonstrates that didymin can ameliorate LPS/D-Gal-induced ALI by inhibiting the glycerophospholipid metabolism and PI3K/Akt and TLR4/NF- κ B pathways., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2023 Lijun Pang et al.)

Recently, with increasing awareness of health issues, non-alcoholic fatty liver disease (NAFLD) has become an epidemic attracting global attention. As a serious chronic disease, NAFLD is clinically managed with pharmacological interventions that are usually associated with poor long-term efficacy and adverse effects. In this scenario, traditional Chinese medicine (TCM) characterized by "multiple ingredients-multiple targets-multiple pathways" shows promise as a potential option to treat NAFLD. Zexie decoction (ZXD) is a classical TCM formula that possesses favorable lipid-lowering and anti-inflammatory activities. Accumulating evidence indicates that ZXD displays robust efficacy in treating NAFLD. The effectiveness of ZXD against NAFLD has been evaluated in our previous studies. This study further examines its probable mechanism of action in an in-depth manner using multi-omic analysis based on the gut-liver axis and sheds light on the potential relationship among genes, hepatic lipid metabolites, and gut microbiotas. Totally, 71 differentially expressed genes (34 upregulated and 37 downregulated genes), 31 differential lipid molecules (8 upregulated and 23 downregulated), and 56 differential gut microbiotas (37 upregulated and 19 downregulated) were identified in the ZXD-treated group rats compared with the negative control group rats. Of these, owing to their key role in the association analysis, g&#95;Blautia, g&#95;Romboutsia, and g&#95;Lactobacillus were hypothesized to be crucial gut microbiotas in the ZXD-mediated treatment of NAFLD. These microbiotas were found to synergize with key genes, such as AKR1B8, CCN1, and TNKS2, and hepatic lipid metabolites, such as glycerophospholipid and sphingomyelin, which might play a therapeutic role by regulating fatty acid synthesis, correcting lipid metabolism disorder, or reducing the inflammatory response. Overall, the present study provides fresh insights into the ZXD-mediated treatment of NAFLD, which, in turn, is expected to give a push to the modernization of TCM., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Hydrolyzed guar gum has gained attention as an anti-obesity agent; however, few studies have focused on its role in amelioration of hepatic-associated metabolic processes. Here, the anti-obesity effect of low molecular weight hydrolyzed guar gum (GMLP, 1-10 kDa) on high-fat diet (HFD)-fed C57BL/6 J mice was investigated via transcriptome and metabolome in liver. GMLP reduced body weight gain and hepatic lipid accumulation dose-dependently, regulated blood lipid levels, and improved liver damage in HFD-fed mice. Integrated transcriptome and metabolome indicated that GMLP mainly altered lipid metabolism pathways (glycerophospholipid metabolism, glycerolipid metabolism, and fatty acid degradation), reduced disease biomarkers of ethyl glucuronide and neopterin, and increased levels of choline, flavin adenine dinucleotide, and pantetheine metabolites. Real-time quantitative PCR showed that GMLP downregulated key genes involved in de novo lipogenesis and triacylglycerol synthesis, while promoting fatty acid oxidation and choline synthesis. This study provides a theoretical basis for GMLP treatment in future clinical applications., Competing Interests: Declaration of competing interest The authors have declared no conflicts of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Paraquat (PQ) is the most widely used herbicide in the world and a well-known potent neurotoxin for humans. PQ exposure has been linked to increase the risk of Parkinson's disease (PD). However, the mechanism underlying its neurotoxic effects in PD pathogenesis is unclear. In our present study, C57BL/6J mice treated with PQ manifested severe motor deficits indicated by the significant reductions in suspension score, latency to fall from rotarod, and grip strength at 8 weeks after PQ exposure. Pathological hallmarks of Parkinsonism in the midbrain such as dopaminergic neuron loss, increased α-synuclein protein, and dysregulated PD-related genes were observed. Non-targeted lipidome analysis demonstrated that PQ exposure alters lipid profile and abundance, increases pro-inflammatory lipids.27 significantly altered subclasses of lipids belonged to 6 different lipid categories. Glycerophospholipids, sphingolipids, and glycerides were the most abundant lipids. Abundance of pro-inflammatory lipids such as Cer, LPC, LPS, and LPI was significantly increased in the midbrain. mRNA expressions of genes regulating ceramide biosynthesis in the midbrain were markedly up-regulated. Moreover, PQ exposure increased serum pro-inflammatory cytokines and provoked neuroinflammation in the midbrain. Pro-inflammatory lipids and cytokines in the midbrain were positively correlated with motor deficits. PQ poisoning in humans significantly also elevated serum pro-inflammatory cytokines and induced an intense systemic inflammation. In summary, we presented initial investigations of PQ induced molecular events related to the PD pathogenesis, capturing aspects of disturbed lipid metabolism, neuroinflammation, impairment of dopaminergic neurons in the midbrain, and an intense systemic inflammation. These neurotoxic effects of PQ exposure may mechanistically contribute to the pathogenesis of PQ induced Parkinsonism. Results of this study also strongly support the hypothesis that ever-increasing prevalence of Parkinson's disease is etiologically linked to the health risk of exposure to neurotoxic environmental pollutants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

High-quality semen with high viability is critical to improving the in-vitro fertilization efficiency. This study aimed to understand the effect of ambient temperature and humidity on semen quality and seminal plasma biochemical parameters of Mediterranean buffalo in March and July. The metabolites of seminal plasma in two seasons were detected using the UPLC-MS/MS method. The results showed that temperature and humidity index (THI) in March were 66.86 ± 2.98, and 82.94 ± 3.52 in July. Compared with in March, breath frequency, rectal temperature, and heat shock protein 70 expressions of seminal plasma were significantly increased in July ( p <  0.05), motility of sperm was dramatically reduced, and sperm deformity rate was significantly increased ( p <  0.05). Fructose, acid phosphatase and α-glucosidase in seminal plasma were significantly increased ( p <  0.05) in July, while testosterone level was significantly reduced ( p <  0.05). Six different metabolites were found in the two groups, which involved in three metabolic pathways, the tricarboxylic acid cycle, glycerophospholipid, glyoxylic acid and dicarboxylic acid. The above results indicate that the increased ambient temperature has obvious side effects on the semen quality of Mediterranean buffalo, and the compromised quality is associated with the change of metabolites related to male hormone secretion, energy metabolism and fatty acid oxidation.

Heat stress (HS) commonly causes boar infertility and economic loss in the swine industry. The heat tolerance of boar semen presents obvious differences among individuals. However, whether heat stress affects motion characteristics and the metabolome profile in boar sperm remains unclear. In this study, the kinetic features of sperm from HS and non-HS (NHS) groups were detected by computer-assisted sperm analysis, and metabolomic profiling was performed by liquid chromatography−mass spectrometry. The results showed that heat stress significantly reduced sperm motility, average path distance (APD), straight-line velocity (VSL), straightness (STR), and linearity (LIN) (p < 0.05). A total of 528 and 194 metabolites in sperm were identified in the positive and negative ion modes, respectively. Lipids and lipid-like molecules, and organic acids and derivatives were major metabolic classes in the two modes. Furthermore, we separately identified 163 and 171 differential metabolites in the two modes between HS and NHS groups. Clustering analysis further revealed significant metabolic changes in sperm after heat stress. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that differential metabolites in the two modes were enriched in glycerophospholipid, choline, and alanine, aspartate, and glutamate and lysine metabolism. Taken together, these results demonstrate that heat stress can alter the motion characteristics and metabolomic profiles of boar sperm.

The present study was to investigate the therapeutical effects and mechanisms of Asiatic acid from Potentilla chinensis against alcoholic hepatitis. Rats were intragastrically fed with alcohol for 12 weeks to induce alcoholic hepatitis and then treated with various drugs for further 12 weeks. The results showed that Asiatic acid significantly alleviated liver injury caused by alcohol in rats, as evidenced by the improved histological changes and the lower levels of AST, ALT, and TBIL. Besides, Asiatic acid significantly enhanced the activity of ADH and ALDH, promoting alcohol metabolism. Asiatic acid suppressed CYP2E1 activity and NADP + /NADPH ratio, resulting in low ROS production. Further study revealed that Asiatic acid markedly reduced hepatocyte apoptosis by regulating the expression levels of apoptosis-related protein. Moreover, Asiatic acid could regulate the Nrf2 and NF-κB signaling pathway, attenuating oxidative stress and inflammation as a result. Interestingly, the comprehensive analysis of transcriptomics and metabolomics indicated that Asiatic acid inhibited the gene expression of Gpat3 and thereby affected the biosynthesis of the metabolites (1-acyl-Sn-glycerol-3-phosphocholine, phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine), regulating the glycerophospholipid metabolism pathway and ultimately ameliorating hepatocyte damage. In conclusion, this study demonstrates that Asiatic acid can ameliorate alcoholic hepatitis by modulating the NF-κB and Nrf2 signaling pathways and the glycerophospholipid metabolism pathway, which may be developed as a potential medicine for the treatment of alcoholic hepatitis., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Colitis is generally affected by multiple factors, including the dysbiosis of intestinal microbiota, and may affect organs outside colon through circulation. Pectin, which is an edible polysaccharide widely present in plant cell walls, has been proved in our previous study to possess preventive potentials against acute ulcerative colitis, especially when the esterification degree is less than 50%. This study aimed to clarify the underlying correlations of gut microbiome and serum metabolites with the preventive effects of pectin with different esterification degrees (H121, L13, and L102) against colitis in mice. MiSeq sequencing data showed that symbiotic bacteria especially beneficial Lactobacillus and Bifidobacterium were enriched by pectin intake. Fiber consumers such as Prevotella and Bacteroides actively responded to L13 pectin, particularly under high dosage (L13-H). In addition, the abnormal abundance of Akkermansia associated with colitis would not appear in mice who had been provided with any of the three pectins before dextran sulfate sodium (DSS) treatment. Furthermore, pre-treatment of H121 and L13 pectins could improve the serum glycerophospholipids such as phosphatidylcholine (PC) and phosphatidylethanolamine (PE). In contrast, lysophosphatidic acid (LPA) contributing to the glycerophospholipid metabolism pathway was enriched only in the L13-H group, which has been previously proved to be associated with the epithelial barrier and intestinal homeostasis. Positive relationships between the glycerophospholipids and the dominant candidates of intestinal bacteria such as Lactobacillus indicated the joint actions of intestinal microbes and serum metabolites as well as the underlying crosstalks among gut microbiome. Therefore, the results of this research suggested that the preventive effects of low-esterified pectin on DSS-induced colitis were likely to be initiated by the enrichment of probiotics in the gut and serum glycerophospholipids. KEY POINTS: • L13 pectin remarkably improved the diversity of the gut microbiome in healthy mice. • Probiotics were enriched and abnormal Akkermansia was restored by L13 and L102 pectins. • Glycerophospholipid metabolism was significantly enriched by H121 and L13 pectins., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The 'core' metabolome of the Bacteroidetes genus Chitinophaga was recently discovered to consist of only seven metabolites. A structural relationship in terms of shared lipid moieties among four of them was postulated. Here, structure elucidation and characterization via ultra-high resolution mass spectrometry (UHR-MS) and nuclear magnetic resonance (NMR) spectroscopy of those four lipids (two lipoamino acids (LAAs), two lysophosphatidylethanolamines (LPEs)), as well as several other undescribed LAAs and N -acyl amino acids (NAAAs), identified during isolation were carried out. The LAAs represent closely related analogs of the literature-known LAAs, such as the glycine-serine dipeptide lipids 430 ( 2 ) and 654. Most of the here characterized LAAs ( 1 , 5 - 11 ) are members of a so far undescribed glycine-serine-ornithine tripeptide lipid family. Moreover, this study reports three novel NAAAs ( N -(5-methyl)hexanoyl tyrosine ( 14 ) and N -(7-methyl)octanoyl tyrosine ( 15 ) or phenylalanine ( 16 )) from Olivibacter sp. FHG000416, another Bacteroidetes strain initially selected as best in-house producer for isolation of lipid 430. Antimicrobial profiling revealed most isolated LAAs ( 1 - 3 ) and the two LPE 'core' metabolites ( 12 , 13 ) active against the Gram-negative pathogen M. catarrhalis ATCC 25238 and the Gram-positive bacterium M. luteus DSM 20030. For LAA 1 , additional growth inhibition activity against B. subtilis DSM 10 was observed.

Research Question: Membrane lipid replacement (MLR) of oxidized membrane lipids can restore sperm cellular membrane functionality and help improve surface protein stability during cryopreservation. What are the effects of MLR with nano-micelles made from a glycerophospholipid (GPL) mixture and cholesterol-loaded cyclodextrin (CLC), on the cryosurvival and expression of acrosome-related proteins in thawed human spermatozoa?, Design: Twenty samples were used to determine the optimum level of nano-micelles by incubation of semen with different concentrations of GPL (0.1 and 1%) and CLC (1 and 2 mg/ml) (including GPL-0.1, GPL-1, CLC-1, CLC-2, CLC-1/GPL-0.1, CLC-2/GPL-0.1, CLC-1/GPL-1 and CLC-2/GPL-1) before cryopreservation. Then, 30 semen samples were collected, and each sample was divided into the following three aliquots: fresh, frozen control and frozen incubated with optimum level of nano-micelles (0.1% GPL and 1 mg/ml CLC)., Results: CLC-1/GPL-0.1 and GPL-0.1 significantly increased motility parameters. CLC-1, GPL-0.1 and CLC-1/GPL-0.1 significantly improved viability rate compared with frozen control group. Significantly higher mitochondrial activity and acrosome integrity, and a lower rate of apoptosis, were observed in the CLC-1/GPL-0.1 compared with the frozen control group. The expression ratios of arylsulfatase A (ARSA), serine protease 37 (PRSS37), serine protease inhibitor Kazal-type 2 (SPINK2) and equatorin (EQTN) significantly increased compared with the frozen control group., Conclusions: Modification of membrane cholesterol and GPL mixtures in spermatozoa enhances their acrosome protein integrity by inhibiting early apoptotic changes and spontaneous acrosome reactions., (Copyright © 2021 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Evidence suggests that ethanol-induced hypertension is associated with increased cardiovascular responsiveness to vasopressors in vivo and enhanced reactivity of isolated arteries to vasopressors ex vivo. The underlying mechanisms are not well understood and the contribution of ethanol metabolites to vascular effects induced by ethanol consumption are unclear. Mesenteric resistance arteries were harvested from Sprague-Dawley rats. Pressure myography was utilized to test effects of ethanol, acetaldehyde and phosphatidylethanol on myogenic tone and on vasoconstriction induced by phenylephrine, arginine vasopressin (aVP), endothelin-1 and KCl. Ethanol, acetaldehyde and phosphatidylethanol concentrations were monitored during the experiments. Ethanol concentrations in the vessel bath decreased with a half-life of 25min; acetaldehyde and phosphatidylethanol concentrations remained constant. Pretreatment with ethanol dose-dependently increased the potency of phenylephrine to induce vasoconstriction 4-fold (p<0.01). These effects were comparable when arteries were pre-treated with a single dose of ethanol for 30min and when ethanol concentrations were kept constant during 30min and 60min of pretreatment. While ethanol also dose-dependently increased the potency of aVP to induce vasoconstriction 1.7-fold (p<0.05), it did not affect vasoconstriction induced by endothelin-1 or KCl. Acetaldehyde pre-treatment (30 min) dose-dependently increased the potency of phenylephrine to induce vasoconstriction 2.7-fold (p<0.01) but did not affect other vasoconstrictor responses. Phosphatidylethanol did not affect any vasoconstrictor responses. Ethanol and its metabolites did not affect myogenic tone. These data suggest that ethanol and acetaldehyde selectively sensitize intrinsic constrictor responses upon activation of vascular α1-adrenergic and/or vasopressin receptors at clinically relevant concentrations. Our findings support the concept that enhanced vasoreactivity to vasoactive hormones contributes to the development of hypertension induced by ethanol consumption. Ex vivo exposure of resistance arteries to ethanol and acetaldehyde resembles effects of chronic ethanol consumption on intrinsic vascular function, and thus could serve as test platform to evaluate interventions aimed to mitigate vascular effects associated with ethanol consumption., Competing Interests: The authors have declared that no competing interests exist.

Purpose: TMX-101 and TMX-202 are formulations of toll-like receptor 7 (TLR-7) agonists, under investigation for the treatment of urothelial carcinoma. Our goal was to evaluate the efficacy of intravesical instillations of TMX-101 or TMX-202 in an orthotopic bladder cancer rat model., Methods: Four groups of 14 rats received an instillation with isogenic AY-27 tumor cells on day 0, starting tumor development. On day 2 and 5, the rats were treated with an intravesical instillation of TMX-101 0.1%, TMX-202 0.38%, vehicle solution or NaCl. On day 12 the rats were sacrificed and the bladders were evaluated histopathologically., Results: No signs of toxicity were seen. The number of tumor-positive rats was 11 of 14 (79%) in the vehicle control group and in the NaCl control group, versus 9 of 14 (64%) in the TMX-101-treated group, and 8 of 14 (57%) in the TMX-20-treated group. The difference between tumor-bearing rats in the treated and control groups was not significant (p = 0.12). Bladder weight was significantly lower for TMX-202-treated rats compared to vehicle (p = 0.005)., Conclusions: TMX-101 and TMX-202 are TLR-7 agonists with antitumor activity. Treatment with TMX-101 and TMX-202 resulted in less tumor-bearing rats compared to vehicle or saline control groups, although not statistically significant. In this aggressive bladder cancer model, a lower number of tumor-positive rats after treatment with TLR-7 agonists indicates activity for the treatment of non-muscle invasive bladder cancer.

Membrane integrity is essential in maintaining sperm viability, signaling, and motility, which are essential for fertilization. Sperm are highly susceptible to oxidative stress, as they are rich in sensitive polyunsaturated fatty acids (PUFA), and are unable to synthesize and repair many essential membrane constituents. Because of this, sperm cellular membranes are important targets of this process. Membrane Lipid Replacement (MLR) with glycerophospholipid mixtures (GPL) has been shown to ameliorate oxidative stress in cells, restore their cellular membranes, and prevent loss of function. Therefore, we tested the effects of MLR on sperm by tracking and monitoring GPL incorporation into their membrane systems and studying their effects on sperm motility and viability under different experimental conditions. Incubation of sperm with mixtures of exogenous, unoxidized GPL results in their incorporation into sperm membranes, as shown by the use of fluorescent dyes attached to GPL. The percent overall (total) sperm motility was increased from 52±2.5% to 68±1.34% after adding GPL to the incubation media, and overall sperm motility was recovered from 7±2% after H2O2 treatment to 58±2.5%)(n = 8, p<0.01) by the incorporation of GPL into sperm membranes. When sperm were exposed to H2O2, the mitochondrial inner membrane potential (MIMP), monitored using the MIMP tracker dye JC-1 in flow cytometry, diminished, whereas the addition of GPL prevented the decrease in MIMP. Confocal microscopy with Rhodamine-123 and JC-1 confirmed the mitochondrial localization of the dyes. We conclude that incubation of human sperm with glycerolphospholipids into the membranes of sperm improves sperm viability, motility, and resistance to oxidizing agents like H2O2. This suggests that human sperm might be useful to test innovative new treatments like MLR, since such treatments could improve fertility when it is adversely affected by increased oxidative stress., Competing Interests: The authors declare that Robert Settineri and Jose Montes are members of the following commercial companies: Sierra Productions Research, LLC and Fertilab, respectively. Gonzalo Ferreira, Carlos Costa, Veronica Bassaizteguy, Romina Cardozo and Marcelo Santos are affiliated with/employed by Universidad de la República and CSIC. Garth L. Nicolson is affiliated with/employed by The Institute for Molecular Medicine and is a part-time consultant to Allergy Research Group. The commercial and academic affiliations stated above for all authors, as well as their employment, consultancy, patents, products in development, or marketed products, etc, do not alter our adherence to PLOS ONE policies on sharing data and materials.

Objectives: To evaluate and compare the pharmacokinetic and pharmacodynamic properties of 2 investigational Toll-like receptor 7 agonists, TMX-101, and TMX-202 after intravenous and intravesical administration in a rat model. TLR-7 agonists are successfully used as topical treatment for various (pre)malignant skin lesions and are now under investigation as intravesical therapy for non-muscle-invasive bladder cancer., Methods: Rats received an intravesical instillation with TMX-101, TMX-202, or vehicle. Additionally 2 groups of rats received an intravenous injection with TMX-101 or TMX-202. Blood sampling was performed at different time points, including pre-exposure and postexposure to determine the plasma concentrations of study drugs for pharmacokinetic and pharmacodynamic analyses and to determine the plasma concentrations of cytokines (IL-2, IL-6, and TNF-α)., Results: We observed no signs of toxicity after intravesical or intravenous administration. There was a limited dose dependent systemic uptake of TMX-101 and TMX-202 after intravesical administration. The systemic uptake of TMX-202 after intravesical instillation was 25 times lower compared to TMX-101., Conclusions: This in vivo study confirms the safety of intravesical TMX-101 and TMX-202 administration, with TMX-202 showing lower systemic uptake. TMX-202 has a larger molecule-mass compared to TMX-101, and it may therefore have a favorable safety profile when treating patients with non-muscle-invasive bladder cancer intravesically., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The increased ability of TMX-202 (derivative of imiquimod) to penetrate the intact stratum corneum (SC) and the follicular orifices of porcine ear skin was shown ex vivo using confocal Raman microscopy and laser scanning microscopy. Moreover, to assess whether TMX-202 is able to reach the immune cells, Langerhans cells extracted from pretreated human skin were investigated ex vivo using confocal Raman microscopy combined with multivariate statistical methods. Tracking the Raman peak of dimethyl sulfoxide centered at 690  cm(−1), the absorption of TMX-202 containing formulation by Langerhans cells was shown. To answer the question whether the TMX-202 active ingredient is able to reach Langerhans cells, the attraction of immune cells to TMX-202 containing formulation treated skin was measured in the in vivo rodent model Mastomys coucha. The results show that TMX-202 active ingredient is able to reach Langerhans cells after penetrating through the intact skin and subsequently attract immune cells. Both the intercellular/transcellular as well as the follicular pathways allow the penetration through the intact barrier of the SC.

Ceramide kinase (CerK) and ceramide-1-phosphate (C1P) are involved in various cellular functions, while regulation of the enzyme activity has not been well elucidated. We herein investigated the effects of several glycerophospholipids on human recombinant CerK activity with CaCl 2 and MgCl 2 by measuring the formation of fluorescent labeled C1P in vitro. CerK activities were 44.1±11.4 (pmol/µg/min) with vehicle, 137±29 with 2 mM CaCl 2 , and 144±32 with 2 mM MgCl 2 in the glycerol/albumin buffer. The addition of glycerophospholipids such as phosphatidylcholine, phosphatidylinositol (PI), PI 4,5-bisphosphate (PI(4,5)P 2 ), and phosphatidic acid had no effect on CerK activity with CaCl 2 , although PI(4,5)P 2 and phosphatidic acid bound to CerK in the lipid-protein overlay assay. The addition of cardiolipin (diphosphatidylglycerol) at concentrations up to 0.1 µM increased, whereas those more than 1 µM decreased CerK activity with CaCl 2 /MgCl 2 . In the lipid-protein overlay assay, cardiolipin bound to CerK and CerK lacking pleckstrin homology (PH) domain, but not PH domain of CerK, in CaCl 2 -independent manner. Cardiolipin also bound to CerK in the multilamellar vesicle binding assay. A deviation from the normal range of cellular cardiolipin, both the decrease by phospholipase D6 expression and increase by an exogenous addition of the lipid, negatively regulated C1P formation in intact HepG2 cells. Our results revealed that cardiolipin bound to CerK and regulated the formation of C1P in vitro and in cells.

Glycerophospholipids and sphingolipids participate in a variety of indispensable metabolic, neurological, and intracellular signaling processes. In this didactic paper we review the biological roles of phospholipids and try to unravel the precise nature of their putative healthful activities. We conclude that the biological actions of phospholipids activities potentially be nutraceutically exploited in the adjunct therapy of widely diffused pathologies such as neurodegeneration or the metabolic syndrome. As phospholipids can be recovered from inexpensive sources such as food processing by-products, ad-hoc investigation is warranted., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objectives: Monocytes are one of the major phagocytic cells that patrol for invading pathogens, and upon activation, differentiate into macrophages or antigen-presenting dendritic cells (DCs) capable of migrating to lymph nodes eliciting an adaptive immune response. The key role in regulating adaptive immune responses has drawn attention to modulate monocyte responses therapeutically within cancer, inflammation and infectious diseases. We present a technology for targeting of monocytes and delivery of a toll-like receptor (TLR) agonist in fresh blood using liposomes with a positively charged surface chemistry., Methods: Liposomes were extruded at 100 nm, incubated with fresh blood, followed by leukocyte analyses by FACS. Liposomes with and without the TLR7 agonist TMX-202 were incubated with fresh blood, and monocyte activation measured by cytokine secretion by ELISA and CD14 and DC-SIGN expression., Results: The liposomes target monocytes specifically over lymphocytes and granulocytes in human whole blood, and show association with 75 - 95% of the monocytes after 1 h incubation. Formulations of TMX-202 in cationic liposomes were potent in targeting and activation of monocytes, with strong induction of IL-6 and IL-12p40, and differentiation into CD14(+) and DC-SIGN+ DCs., Conclusion: Our present liposomes selectively target monocytes in fresh blood, enabling delivery of TLR7 agonists to the intracellular TLR7 receptor, with subsequent monocyte activation and boost in secretion of proinflammatory cytokines. We envision this technology as a promising tool in future cancer immunotherapy.

Membrane phospholipids can function as potent regulators of ion channel function. This study uncovers and investigates the effect of phosphatidic acid on Kv channel gating. Using the method of reconstitution into planar lipid bilayers, in which protein and lipid components are defined and controlled, we characterize two effects of phosphatidic acid. The first is a non-specific electrostatic influence on activation mediated by electric charge density on the extracellular and intracellular membrane surfaces. The second is specific to the presence of a primary phosphate group, acts only through the intracellular membrane leaflet and depends on the presence of a particular arginine residue in the voltage sensor. Intracellular phosphatidic acid accounts for a nearly 50 mV shift in the midpoint of the activation curve in a direction consistent with stabilization of the voltage sensor's closed conformation. These findings support a novel mechanism of voltage sensor regulation by the signaling lipid phosphatidic acid.

Background: The Toll-like receptor 7 (TLR7) activator imiquimod (IMQ) is safe and effective in treating actinic keratosis; however, an intermittent treatment regimen is necessary because of excessive local reactions., Objectives: To evaluate in vitro potency, pharmacodynamics/pharmacokinetics, toxicity and efficacy in vivo of the newly developed TLR7 ligand-phospholipid conjugate, TMX-202, in a gel formulation., Material and Methods: The effects of TMX-202 were assessed both in vitro on a murine macrophage cell line and in primary bone marrow-derived dendritic cells and in vivo on mice (C57BL/6-wild type, Myd88(-/-) and Tlr7(-/-))., Results: TMX-202 was more potent than IMQ in vitro using murine and human cells. In contrast, in vivo it showed less systemic pro-inflammatory activity and better safety than IMQ. Moreover, the TMX-202 gel formulation exhibited at least comparable efficacy to Aldara in a mouse model for skin proliferative diseases., Conclusion: TMX-202 is safe and efficacious without causing excessive adverse effects, suggesting that it may be an alternative to Aldara for the treatment of proliferative skin conditions.

Background and Purpose: The development of potent and selective inhibitors of the biosynthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG) via DAG lipases (DAGL) α and β is just starting to be considered as a novel and promising source of pharmaceuticals for the treatment of disorders that might benefit from a reduction in endocannabinoid tone, such as hyperphagia in obese subjects., Experimental Approach: Three new fluorophosphonate compounds O-7458, O-7459 and O-7460 were synthesized and characterized in various enzymatic assays. The effects of O-7460 on high-fat diet intake were tested in mice., Key Results: Of the new compounds, O-7460 exhibited the highest potency (IC₅₀ = 690 nM) against the human recombinant DAGLα, and selectivity (IC₅₀ > 10 μM) towards COS-7 cell and human monoacylglycerol lipase (MAGL), and rat brain fatty acid amide hydrolase. Competitive activity-based protein profiling confirmed that O-7460 inhibits mouse brain MAGL only at concentrations ≥ 10 μM, and showed that this compound has only one major 'off-target', that is, the serine hydrolase KIAA1363. O-7460 did not exhibit measurable affinity for human recombinant CB₁ or CB₂ cannabinoid receptors (Ki > 10 μM). In mouse neuroblastoma N18TG2 cells stimulated with ionomycin, O-7460 (10 μM) reduced 2-AG levels. When administered to mice, O-7460 dose-dependently (0-12 mg·kg⁻¹, i.p.) inhibited the intake of a high-fat diet over a 14 h observation period, and, subsequently, slightly but significantly reduced body weight., Conclusions and Implications: O-7460 might be considered a useful pharmacological tool to investigate further the role played by 2-AG both in vitro and in vivo under physiological as well as pathological conditions., (© 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.)

The bovine milk fat globule membrane (MFGM) contains several antimicrobial components with proven efficacy in vitro, but in vivo evidence is scarce. The present study was performed to determine the efficacy of the bovine MFGM in vivo. Rats were fed diets based on bovine skimmed milk powder (low in MFGM) or bovine sweet buttermilk powder (high in MFGM). After dietary adaptation, rats were orally infected with Salmonella enteritidis or Listeria monocytogenes. Whereas sweet buttermilk powder did not protect rats against infection with S. enteritidis, it protected against L. monocytogenes, as shown by a lower colonisation and translocation of this pathogen. Protection coincided with higher listericidal capacity of gastric and caecal contents. The digestion products of phosphoglycerides and sphingomyelin are bactericidal in vitro. To study their role, rats were fed diets containing either 0·1 % phosphatidylcholine or sphingomyelin, or a control diet. After dietary adaptation, rats were infected with L. monocytogenes. Since Listeria colonisation was not affected by these diets, phosphoglycerides and sphingomyelin are not involved in the protective effect of sweet buttermilk. Additional in vitro experiments were performed to further explore the mechanism of the beneficial effects of sweet buttermilk. Inhibition of the adherence of L. monocytogenes to the intestinal mucosa is the most likely explanation, since sweet buttermilk powder inhibited the binding of L. monocytogenes in both a haemagglutination assay and a Caco-2 cell adherence assay. In conclusion, sweet buttermilk powder, which is rich in MFGM, protects against L. monocytogenes infection in rats, probably by preventing adherence of this pathogen to the intestinal mucosa.

In this paper, using high-performance liquid chromatography methods were quantitatively and qualitatively identified most biological important high fatty acids, contained in Rkatsiteli grape seed oil of 2010 years crop in Signakhi region of Georgia. The chromatography investigation showed, that the grape seed oil contained 61% linolic acid, 19% oleic, 8% palmitic, 4.5% stearic, 1.4% linolenic and 0.6% arachidonuic acids. In standard diet grape seed oil was added as a food additive (5.0 gr and 10.0 gr on 1.0 kg food). After 15 days fatty acids are carried out from mouse liver (120 inbred mouse), fractioned and using high-performance liquid chromatography the retention values of individual fatty asids are identiced. The investigation showed different sensitivity of components contained in grape seed oil.

Background: The components of the nutritional supplement Cognitex have been individually shown to have beneficial effects on cognitive function. We evaluated the efficacy of the nutritional supplement in improving cognitive function in elderly with memory complaints., Methods: Thirty participants received three capsules of the nutritional supplement per day for 12 weeks in an open label study. Efficacy and safety measures, assessed at baseline, 2 weeks, and 12 weeks of treatment, included cognitive evaluation using a computerized cognitive assessment tool, vital signs measurements, and physical examination., Results: Twenty-six participants completed the 12-week study. A significant improvement in memory abilities (recall, recognition, and spatial short term) was observed following 2 weeks of Cognitex treatment (mean change from baseline: 11.15 ± 2.90, 8.68 ± 2.50, and 19.85 ± 6.19, respectively). Attention (sustained and focused), visual learning, and activities of daily living (executive functions and mental flexibility) were improved as well following this short supplementation period (mean change from baseline: 9.46 ± 3.80, 3.76 ± 1.50, 17.31 ± 5.33, 9.45 ± 3.73, and 9.92 ± 4.08, respectively). After 10 additional treatment weeks, activities of daily living demonstrated an additional statistically significant improvement while the beneficial effect observed for the rest of the tested parameters remained unchanged., Conclusions: The results indicate that the nutritional supplement may improve cognitive performance in elderly with memory complaints; however, further blinded and placebo-controlled studies are needed., Trial Registration: Clinicaltrials.gov, Identifier: NCT00719953.

This paper describes the inhibitory activities of diacylglyceride phospholipids, such as phosphatidylcholine (lecithin), phosphatidylethanolamine (cephalin), phosphatidylserine, phosphatidylglycerol, bisphosphatidylglycerol (cardiolipin), phosphatidylinositol, and phosphatidic acid (phosphatidate) (compounds 1 - 7, respectively) against DNA polymerase (pol), DNA topoisomerase (topo), and human cancer cell growth. Among the compounds tested, compounds 3 - 7 were revealed to be potent inhibitors of animal pols: compound 4 was the strongest inhibitor, with IC(50) values for different pols of 1.7 - 15 mM. Compounds 4 - 7 also inhibited the activity of human topo II: compound 7 was the strongest inhibitor, with an IC50 value of 20 mM. The glycerophospholipids had no effect on the activities of plant (cauliflower) pol a, prokaryotic pols, or other DNA metabolic enzymes, such as calf primase of pol a, T7 RNA polymerase, T4 polynucleotide kinase, and bovine deoxyribonuclease I. These results suggest that compounds 3 - 7 are selective inhibitors of animal pols and human topos. Compounds 4 and 7 also suppressed the growth of a human colon carcinoma cell line that lacked p53 (HCT116 p53(-/-)); their LD(50) values were 63.6 and 51.1 mM, respectively, suggesting that cell growth inhibition by these compounds leads to the inhibition of pols and/or topos. From these findings, diacylglyceride phospholipids, which are present in various foods, might be effective nutrients for promoting human anti-cancer health promotion.

The effects were evaluated of various glycerophospholipids on the uptake of beta-carotene solubilized in mixed micelles by human intestinal Caco-2 cells. Phosphatidylethanolamine markedly enhanced the transfer of beta-carotene from the micelles to the cells, whereas phosphatidylcholine suppressed it. All the lysoglycerophospholipids enhanced the transfer, irrespective of the polar head group. Glycerophospholipids therefore have the potential to modify the intestinal absorption of carotenoids.

An imbalance in (n-6)/(n-3) PUFA has been reported in cystic fibrosis (CF) patients. Glycerophospholipids enriched in docosahexaenoic acid (GPL-DHA) have been shown to regulate the (n-6)/(n-3) fatty acid ratio in the elderly. Here, we tested the effect of GPL-DHA supplementation on PUFA status in F508del homozygous CF mice. GPL-DHA liposomes were administrated by gavage (60 mg DHA/kg daily, i.e. at maximum 1.4 mg DHA/d) to 1.5-mo-old CF mice (CF+DHA) and their corresponding wild-type (WT) homozygous littermates (WT+DHA) for 6 wk. The PUFA status of different tissues was determined by GC and compared with control groups (CF and WT). There was an alteration in the (n-6) PUFA pathway in several CF-target organs in CF compared with WT mice, as evidenced by a higher level of arachidonic acid (AA) in membrane phospholipids or whole tissue (21 and 39% in duodenum-jejunum, 32 and 38% in ileum, and 19 and 43% in pancreas). Elevated AA levels were associated with lower linoleic acid (LA) and higher dihomo-gamma-linolenic acid levels. No DHA deficiency was observed. GPL-DHA treatment resulted in different PUFA composition changes depending on the tissue (increase in LA, decrease in elevated AA, DHA increase, increase in (n-6)/(n-3) fatty acid ratio). However, the DHA/AA ratio consistently increased in all tissues in CF+DHA and WT+DHA mice. Our study demonstrates the effectiveness of an original oral DHA formulation in counter-balancing the abnormal (n-6) fatty acid metabolism in organs of CF mice when administrated at a low dose and highlights the potential of the use of GPL-DHA as nutritherapy for CF patients.

In response to various exogenous stimuli, mast cells (MCs) release a wide variety of inflammatory mediators stored in their cytoplasmic granules and this release initiates subsequent allergic reactions. Lysophosphatidylserine (lysoPS) has been known as an exogenous inducer to potentiate histamine release from MCs, though even at submicromolar concentrations. In this study, through SAR studies on lysoPS against MC degranulation, we identified lysoPT, a threonine-containing lysophospholipid and its 2-deoxy derivative as novel strong agonists. LysoPT and its 2-deoxy derivative induced histamine release from MCs both in vitro and in vivo at a concentration less than one-tenth that of lysoPS. Notably, lysoPT did not activate a recently proposed lysoPS receptor on MCs, GPR34, demonstrating the presence of another undefined receptor reactive to both lysoPS and lysoPT that is involved in MC degranulation. Thus, the present strong agonists, lysoPT and its 2-deoxy derivative, will be useful tools to understand the mechanisms of lysoPS-induced activation of degranulation of MCs.

The aim of this study was to provide a basis for examining the molecular mechanism for the pharmacological action of ethanol. Energy transfer between the surface fluorescent probe 1-anilinonaphthalene-8-sulfonic acid and hydrophobic fluorescent probe 1,3-di(1-pyrenyl)propane was used to examine the effect of both dimyristoylphosphatidylethanol (DMPEt) and ethanol on the thickness (D) of the synaptosomal plasma membrane vesicles (SPMV) isolated from the bovine cerebral cortex. The thickness (D) of the intact SPMV was 1.044 +/- 0.008 (arbitrary units, n=5) at 37 degrees C (pH 7.4). Both DMPEt and ethanol decreased the thickness of the SPMV lipid bilayer in a dose-dependent manner with a significant decrease in thickness observed at 5 microM and 25 mM, respectively. It was assumed that both ethanol and DMPEt cause interdigitation in the SPMV lipid bilayers. The effects of ethanol on the neuronal membranes were attributed to its direct and indirect actions. The indirect action of ethanol refers to the action of phosphatidylethanol, which is an ethanol abnormal metabolite, on the neuronal membranes. The decrease in membrane thickness by both DMPEt and ethanol might be responsible for some, but not all of its anesthetic actions.

Lysophosphatidic acid (LPA) is a simple phospholipid but has numerous biological effects through a series of G-protein-coupled receptors specific to LPA. In general, LPA is short-lived when applied in vivo, which hinders most pharmacological experiments. In our continuing study to identify stable LPA analogues capable of in vivo applications, we identified here lysophosphatidylmethanol (LPM) as a stable and pan-LPA receptor agonist. A synthetic LPM activated all five LPA receptors (LPA(1-5)), and stimulates both cell proliferation and LPA-receptor-dependent cell motility. In addition, LPM showed a hypertensive effect in rodent when applied in vivo. We found that, when fetal calf serum was incubated in the presence of methanol, formation of LPM occurred rapidly, whereas it was completely blocked by depletion of autotaxin (ATX), a plasma enzyme that converts lysophosphatidylcholine (LPC) to LPA. When recombinant ATX was incubated with LPC in the presence of methanol, both LPM and LPA were produced with a ratio of 1:10, showing that ATX has transphosphatidylation activity in addition to its lysophospholipase D activity. Administration of methanol in mice resulted in the formation of several micromoles of LPM in plasma, which is much higher than that of LPA. The present study identified LPM as a novel and stable lysophospholipid mediator with LPA-like activities and ATX as a potential synthetic enzyme for LPM.

Background: Previous epidemiological studies have shown that light to moderate alcohol consumption has protective effects against coronary heart disease but the mechanisms of the beneficial effect of alcohol are not known. Ethanol may increase high density lipoprotein (HDL) cholesterol concentration, augment the reverse cholesterol transport, or regulate growth factors or adhesion molecules. To study whether qualitative changes in HDL phospholipids mediate part of the beneficial effects of alcohol on atherosclerosis by HDL receptor, we investigated whether phosphatidylethanol (PEth) in HDL particles affects the secretion of vascular endothelial growth factor (VEGF) by a human scavenger receptor CD36 and LIMPII analog-I (CLA-1)-mediated pathway., Methods: Human EA.hy 926 endothelial cells were incubated in the presence of native HDL or PEth-HDL. VEGF concentration and CLA-1 protein expression were measured. Human CLA-1 receptor-mediated mechanisms in endothelial cells were studied using CLA-1 blocking antibody and protein kinase inhibitors., Results: Phosphatidylethanol-containing HDL particles caused a 6-fold increase in the expression of CLA-1 in endothelial cells compared with the effect of native HDL. That emergent effect was mediated mainly through protein kinase C and p44/42 mitogen-activated protein kinase pathways. PEth increased the secretion of VEGF and that increase could be abolished by a CLA-1 blocking antibody., Conclusions: High density lipoprotein particles containing PEth bind to CLA-1 receptor and thereby increase the secretion of VEGF from endothelial cells. Ethanol-induced protective effects against coronary heart disease may be explained, at least partly, by the effects of PEth-modified HDL particles on VEGF via CLA-1-mediated mechanisms in endothelial cells.

Purpose: To determine molecular mechanisms for the release of 11-cis-retinal from the binding pocket of cellular retinaldehyde-binding protein (CRALBP)., Methods: Binding of CRALBP to lipid surfaces was assessed with a lipid-immunoblot assay. Lipids were presented to CRALBP as small unilamellar vesicles (SUVs) consisting of phosphatidylcholine (PC) plus other lipids. Release of 9-cis-retinal or 11-cis-retinal from CRALBP was measured with spectral and high performance liquid chromatography (HPLC) assays based on the protection of the protein-bound retinal carbonyl group from reaction with NH(2)OH. The electrostatic surface potential of CRALBP was calculated from a model of its structure using the program CCP4mg., Results: Incubation of CRALBP.11-cis-retinal with lipids absorbed on nitrocellulose revealed binding to the acidic lipids, phosphatidic acid (PA)>phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P(3)]>phosphatidylserine (PS)> PI(4,5)P(2) and little or no binding to PC, phosphatidylethanolamine (PE), or PI(4)P. 11-cis-retinal was released during incubation of CRALBP with SUVs consisting of PC plus 50 mol% PA but not during incubation with those composed of 100 mol% PC. The efficacy of release of 9-cis-retinal or 11-cis-retinal from CRALBP by phospholipid-containing SUVs generally paralleled that of the binding of CRALBP to the lipids (PA>PS>PI>>PC). Examination of the electrostatic surface potential of the protein structure revealed a basic recess on one face of the protein, which may bind acidic lipids., Conclusions: Our results identify the first physiologic substances that release 11-cis-retinal from CRALBP. PA and PS are relatively minor membrane lipids that can be generated in the cytoplasmic leaflet of the plasma membrane in response to various signal transduction pathways, where they could interact with cytosolic CRALBP. The mechanism for release of retinal from CRALBP by acidic lipids remains to be determined but could involve binding of the acidic lipid in the 11-cis-retinal binding site or to the positive basic recess on the protein surface. These results open a new facet in our understanding of how CRALBP functions in the regeneration of visual pigments.

Free radical-mediated oxidation of (poly)unsaturated glycerophospholipids in membranes and lipoproteins leads to the formation of a plethora of products. Some of these oxidized phospholipids, especially the truncated forms, induce apoptosis depending on their chemical structure, concentration and cell type. Depending on the phospholipid and the cell type, two pathways have so far been identified for the intracellular transmission of the apoptotic signals. One pathway involves activation of acid sphingomyelinase, which gives rise to the formation of ceramide and is followed by phosphorylation of pro-apoptotic mitogen-activated protein kinases. Alternatively, oxidized phospholipids act directly on mitochondria leading to efflux of pro-apoptotic effectors in endothelial cells. During the execution of the apoptotic program additional oxidized phospholipids are generated. The apoptotic cascade itself leads to oxidation and exposure of e.g. membrane phosphatidylserine. Oxidized phospholipids on the outer leaflet of the plasma membrane can form surface lipid patterns that specifically bind to phagocytic cells, e.g. macrophages.In this manuscript we review the recent literature reporting on apoptosis-inducing glycerophospholipids. In addition, we describe the cellular processes that lead to phospholipid oxidation as part of the apoptotic mode of cell death and are likely to enhance the recognition of apoptotic cells by phagocytic macrophages.

The NGF secretion from cultured mouse astrocytes was enhanced by sublethal concentrations of phosphatidic acid (PA), ceramide, or sphingosine (Sph), and concentration dependently by lysophosphatidic acid (LPA), sphingosylphosphorylcholine (SPC), or sphingosine-1-phosphate (S1P), but was unaffected by any concentrations of phosphatidylcholine (PC), phosphatidylethanolamine (PE) or sphingomyelin (SM). The enhancement of NGF synthesis by Sph was completely inhibited by the addition of ceramide synthase inhibitor, fumonisin B1. LPA and S1P showed similar hyperbolic curves with maximum NGF secretion at concentrations of more than 50 microM, but they showed no proliferative effect on quiescent astrocytes. The mechanisms underlying the stimulation of NGF synthesis by 50 microM LPA and 50 microM S1P were further investigated by using various inhibitors. One of the protein kinase C (PKC) inhibitors, Gö6976, suppressed the LPA- and S1P-stimulated NGF synthesis by 70 and 80%, respectively. LPA and S1P were found to activate common multiple signaling pathways for NGF production, involving the activation of the protein kinase C (PKC), mitogen-activated protein (MAP) kinase, and phosphatidylinositol 3-kinase (PI-3K) pathways.

Background: Lactobacilli represent a major component of the human microbiota. In this study we investigated whether and how Lactobacillus fermentum inhibits the proinflammatory responses of human epithelial cells on Yersinia enterocolitica infection., Methods: Human epithelial cells were exposed to Y. enterocolitica pYV(-) or L. fermentum or to both strains, combinations of heat-killed L. fermentum or supernatant of L. fermentum cultures and Y. enterocolitica. The modulation of Y. enterocolitica induced IL-8 levels in the culture supernatants was determined and activation of Rac, p38, and NF-kappaB was investigated., Results: Exposure of human epithelial cells to L. fermentum does not induce NF-kappaB activation and subsequent IL-8 secretion in HeLa cells, whereas Y. enterocolitica induces NF-kappaB activation and high levels of IL-8. Viable L. fermentum, supernatant of L. fermentum cultures, but not heat-killed L. fermentum, inhibited IL-8 secretion of HeLa cells triggered by Y. enterocolitica. Lactobacillus fermentum-exposed HeLa cells showed decreased Rac, p38, and NF-kappaB activation after Y. enterocolitica infection. Treatment of L. fermentum supernatants with phospholipase C abolished the inhibitory effect, indicating that a secreted phospholipid mediates the antiinflammatory properties of L. fermentum. Adhesion to or invasion of Y. enterocolitica into epithelial cells was not altered by coincubation with L. fermentum., Conclusion: Our results lead to the conclusion that L. fermentum inhibits the Y. enterocolitica-induced IL-8 production by a possibly secreted phospholipid of <10 kDa molecular weight. These data suggest that L. fermentum may have probiotic properties modulating intestinal inflammatory responses and might offer new therapeutic strategies in the treatment of intestinal inflammatory diseases.

A new erythroblastic leukemia cell line (EEB) was established from a patient with early erythroblastic leukemia. The cells had features of immature erythroblasts, including an agranular basophilic cytoplasm and CD36, CD71, CD175s (sialyl-Tn) and CD235a (glycophorin A) expression without CD41 expression, myeloperoxidase activity and platelet-peroxidase activity. The cells were confirmed to be of the erythroid lineage based on expression of the gamma-globin message. They were induced to differentiate into benzidine-positive cells by hemin and delta-amino levulinic acid (delta-ALA). An analysis of cell membrane lipids showed that EEB cells contain a type of glycerolipid, phosphatidylglucose (PhGlc), but not unbranched type 2 chains, i antigens. GL-7 which is a recombinant Fab fragment of GL-2 and binds to PhGlc, induced production of hemoglobin F (HbF) associated with accumulation of the gamma-globin (gamma-globin) message in EEB cells. The GL-7-mediated erythroid differentiation was associated with apoptosis. These results suggest that direct signaling to PhGlc mediates erythroid differentiation and apoptosis in EEB cells.

Two new analogues derived from the platelet activating factor (PAF), containing glucosamine instead of the acetyl group, were synthesized, and their effect on the human keratinocyte cell line HaCaT was evaluated with respect to cytotoxicity, proliferation, adhesion, and migration. Starting with (R)-1,2-isopropylideneglycerol (3), the glycosylation acceptor 1-O-octadecyl-3-O-tert-butyldimethylsilyl-sn-glycerol (6) was synthesized in three steps. Glycosylation of 6 with the already known O-(3,4,6-tri-O-acetyl-2-deoxy-2-dimethylmaleimido-beta-D-glycopyranosyl)trichloracetimidate gave 1-O-octadecyl-2-O-(3',4',6'-tri-O-acetyl-2'-deoxy-2'-dimethylmaleimido-beta-D-glucopyranosyl)-3-O-tert-butyldimethylsilyl-sn-glycerol (7). After removing the (tert-butyldimethyl)silyl (TBDMS) group with FeCl3x6H2O, phosphoryl choline was introduced, yielding [1-O-octadecyl-2-O-(2'-deoxy-2'-dimethylmaleimido-beta-D-glucopyranosyl)-sn-glycero(3)]phosphorylcholine (2) (glucosimide-PAF). pH controlled cleavage of the amino protection group gave [1-O-octadecyl-2-O-(2'-deoxy-2'-amino-beta-D-glucopyranosyl)-sn-glycero(3)]phosphorylcholine hydrochloride (1) (glucosamine-PAF). 2 inhibited proliferation of HaCaT cells by 26% at nontoxic concentrations, while 1 increased the proliferation rate by 30% at low concentrations. At higher concentrations, both compounds showed cytotoxic properties with LD50 = 30 micromol/L (1) and LD50 = 5-6 micromol/L (2). Both 1 and 2 were potent promoters of cell adhesion and migration of HaCaT cells.

The aim of this study was to provide the basis to further examine the mode of action of ethanol. Fluorescent probes reported to have different membrane mobilities were used to evaluate the effect of dimyristoylphosphatidylethanol (DMPEt) on the lateral and rotational mobilities of liposome lipid bilayers. An experimental procedure, based on the selective quenching of 1,6-diphenyl-1,3,5-hexatriene (DPH) and 1,3-di(1-pyrenyl)propane (Py-3-Py) by trinitrophenyl groups, was used. DMPEt increased the bulk lateral and rotational mobilities, and had a greater fluidizing effect on the outer than the inner monolayer. These effects of DMPEt on liposomes may be responsible for some, but not all, of the general anesthetic actions of ethanol.

This is the first report describing the cloning and characterization of sterol carrier protein-2 (SCP-2) from plants. Arabidopsis thaliana SCP-2 (AtSCP-2) consists of 123 amino acids with a molecular mass of 13.6 kDa. AtSCP-2 shows 35% identity and 56% similarity to the human SCP-2-like domain present in the human D-bifunctional protein (DBP) and 30% identity and 54% similarity to the human SCP-2 encoded by SCP-X. The presented structural models of apo-AtSCP-2 and the ligand-bound conformation of AtSCP-2 reveal remarkable similarity with two of the structurally known SCP-2s, the SCP-2-like domain of human DBP and the rabbit SCP-2, correspondingly. The AtSCP-2 models in both forms have a similar hydrophobic ligand-binding tunnel, which is extremely suitable for lipid binding. AtSCP-2 showed in vitro transfer activity of BODIPY-phosphatidylcholine (BODIPY-PC) from donor membranes to acceptor membranes. The transfer of BODIPY-PC was almost completely inhibited after addition of 1-palmitoyl 2-oleoyl phosphatidylcholine or ergosterol. Dimyristoyl phosphatidic acid, stigmasterol, steryl glucoside, and cholesterol showed a moderate to marginal ability to lower the BODIPY-PC transfer rate, and the single chain palmitic acid and stearoyl-coenzyme A did not affect transfer at all. Expression analysis showed that AtSCP-2 mRNA is accumulating in most plant tissues. Plasmids carrying fusion genes between green fluorescent protein and AtSCP-2 were transformed with particle bombardment to onion epidermal cells. The results from analyzing the transformants indicate that AtSCP-2 is localized to peroxisomes.

Fluorescent probes located in different membrane regions were used to evaluate the effects of dimyristoylphosphatidylethanol (DMPEt) on the structural parameters (transbilayer rotational and lateral mobility, annular lipid fluidity and protein distribution) of synaptosomal plasma membrane vesicles (SPMV) from the bovine cerebral cortex. An experimental procedure was used based on selective quenching of 1,6-diphenyl-1,3,5-hexatriene (DPH) and 1,3-di(1-pyrenyl)propane (Py-3-Py) by trinitrophenyl groups, and radiationless energy transfer from the tryptophans of membrane proteins to Py-3-Py. DMPEt increased the bulk lateral and rotational mobility, and annular lipid fluidity of SPMV lipid bilayers, and had a greater fluidizing effect on the outer monolayer than the inner monolayer. It also caused membrane proteins to cluster. These effects of DMPEt on neuronal membranes may be responsible for some, though not all, of the general anesthetic actions of ethanol.

Aims: Although long-term exposure of hepatocytes to ethanol results in agonist-selective potentiation of p42/44 mitogen-activated protein kinase (MAPK) activation, mediators of this effect of ethanol are not known., Methods: We examined the role of phosphatidylethanol (PEth), a novel phospholipid formed exclusively in the presence of ethanol., Results: PEth accumulated in primary cultures of rat hepatocytes treated with ethanol. Exogenously added PEth potentiated angiotensin II-stimulated p42/44 MAPK similarly to that observed with ethanol treatment of cells for 24 h, a condition where PEth accumulates. PEth levels remained elevated 2 h after ethanol removal subsequent to a 24-h exposure, and the potentiating effects of ethanol were also present. PEth did not potentiate p42/44 MAPK activation by either epidermal growth factor or vasopressin, thus further mimicking the known agonist selectivity for this ethanol effect., Conclusions: These results offer a novel role for PEth as a mediator in the ethanol modulation of p42/44 MAPK cascade in hepatocytes.

We have reported previously that the ceramidase from Pseudomonas aeruginosa AN17 isolated from a patient with atopic dermatitis requires detergents for hydrolysis of ceramide (Cer) [Okino, Tani, Imayama and Ito (1998) J. Biol. Chem. 273, 14368--14373]. In the present study, we report that some glycerophospholipids strongly activated the hydrolysis of Cer by Pseudomonas ceramidase in the absence of detergents. Among the glycerophospholipids tested, cardiolipin was most effective in stimulating hydrolysis of Cer followed by phosphatidic acid, phosphatidylethanolamine and phosphatidylglycerol, whereas phosphatidylcholine, lysophosphatidic acid and diacylglycerol were less effective. Interestingly, Staphylococcus aureus-derived lipids, which contain cardiolipin and phosphatidylglycerol as major lipid components, also strongly enhanced the hydrolysis of normal Cer, as well as the human skin-specific omega-hydroxyacyl Cer, by the enzyme in the absence of detergents. It was confirmed that several strains of P. aeruginosa, including AN17, secrete a significant amount of staphylolytic proteases to lyse S. aureus cells, resulting in the release of cardiolipin and phosphatidylglycerol. Since both P. aeruginosa and S. aureus are suspected of being present in microflora of atopic skin, we speculate that S. aureus-derived glycerophospholipids stimulate the hydrolysis of Cer in atopic skin by bacterial ceramidase.