Structural Determination of Three Sphingolipids from Two Marine-derived Mangrove Endophytic Fungal Strains

A set of three sphingolipids, N-2′-hydroxyplmitoyl-1-O-β-D-glucopyranosyl-9-methyl-4E, 8E-sphingadiene （A）, N-2′-hydroxyl-3′E-octadecenoyl-1-O-β-D-glucopyranosyl-9-methyl-4E, 8E-sphingediene （B） and N-palmitoyldihydrosphingosine （C）, were isolated from two marine-derived mangrove endophytic fungal strains （strains No. 1924 and 3893） from the South China Sea. Their structures were elucidated by 2D NMR and FABMS methods. It is the first time that these sphingolipids were separated and obtained from marine-derived mangrove endophytic fungus from the South China Sea.

Bile acids and sphingolipids in cholangiocarcinoma

Objective:Cholangiocarcinoma(CCA)is a rare but highly malignant hepatobiliary cancer with a very poor prognosis and limited treatment options.CCA is commonly associated with chronic cholestasis and significantly elevated levels of primary and conjugated bile acids(CBAs),which are correlated with bile duct obstruction.

Sphingolipids in cardiovascular and cerebrovascular systems:Pathological implications and potential therapeutic targets

The sphingolipid metabolites ceramide,sphingosine,and sphingosine-1-phosphate(S1P) and its enzyme sphingosine kinase(SphK) play an important role in the regulation of cell proliferation,survival,inflammation,and cell death.Ceramide and sphingosine usually inhibit proliferation and promote apoptosis,while its metabolite S1P phosphorylated by SphK stimulates growth and suppresses apoptosis.Because these metabolites are interconvertible,it has been proposed that it is not the absolute amounts of these metabolites but rather their relative levels that determine cell fate.The relevance of this "sphingolipid rheostat" and its role in regulating cell fate has been borne out by work in many labs using many different cell types and experimental manipulations.A central finding of these studies is that SphK is a critical regulator of the sphingolipid rheostat,as it not only produces the pro-growth,anti-apoptotic messenger S1P,but also decreases levels of pro-apoptotic ceramide and sphingosine.Activation of bioactive sphingolipid S1P signaling has emerged as a critical protective pathway in response to acute ischemic injury in both cardiac and cerebrovascular disease,and these observations have considerable relevance for future potential therapeutic targets.

Emerging roles and therapeutic potentials of sphingolipids in pathophysiology:emphasis on fatty acyl heterogeneity

Sphingolipids not only exert structural roles in cellular membranes,but also act as signaling molecules in various physiological and pathological processes.A myriad of studies have shown that abnormal levels of sphingolipids and their metabolic enzymes are associated with a variety of human diseases.Moreover,blood sphingolipids can also be used as biomarkers for disease diagnosis.This review summarizes the biosynthesis,metabolism,and pathological roles of sphingolipids,with emphasis on the biosynthesis of ceramide,the precursor for the biosynthesis of complex sphingolipids with different fatty acyl chains.The possibility of using sphingolipids for disease prediction,diagnosis,and treatment is also discussed.Targeting endogenous ceramides and complex sphingolipids along with their specific fatty acyl chain to promote future drug development will also be discussed.

Changes of sphingolipids profiles after ischemia-reperfusion injury in the rat liver

Background Hepatic ischemia-reperfusion （I/R） injury occurs in many clinical procedures. The molecular mechanisms responsible for hepatic I/R injury however remain unknown. Sphingolipids, in particular ceramide, play a role in stress and death receptor-induced hepatocellular death, contributing to the progression of several liver diseases including liver I/R injury. In order to further define the role of sphingolipids in hepatic I/R, systemic analysis of sphingolipids after reperfusion is necessary. Methods We investigated the lipidomic changes of sphingolipids in a rat model of warm hepatic I/R injury, by delayed extraction matrix-assisted laser desorption ionization time-of-flight mass spectrometry （DE MALDI-TOF-MS）. Results The total amounts of ceramide and sphingomyelin and the intensity of most kinds of sphingolipids, mainly sphingomyelin, significantly increased at 1 hour after reperfusion （P 〈0.05） and reached peaks at 6 hours after reperfusion （P 〈0.01） compared to controls. Six new forms of ceramide and sphingomyelins appeared 6 hours after reperfusion, they were （m/z） 537.8, 555.7, 567.7, 583.8, 683.5 and 731.4 respectively. A ceramide-monohexoside （m/z） 804.4 （CMH（d18：1C22：1＋Na）＋） also increased after reperfusion and correlated with extent of liver injury after reperfursion. Conclusions Three main forms of sphingolipids, ceramide, sphingomyelin and ceramide-monohexoside, are related to hepatic I/R injury and provide a new perspective in understanding the mechanisms responsible for hepatic I/R injury.

Bile acids and sphingolipids in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is one of the fastest-growing diseases, and its global prevalence is estimated to increase >50% by 2030. NAFLD is comorbid with metabolic syndrome, obesity, type 2 diabetes, and insulin resistance. Despite extensive research efforts, there are no pharmacologic or biological therapeutics for the treatment of NAFLD. Bile acids and sphingolipids are well-characterized signaling molecules. Over the last few decades, researchers have uncovered potential mechanisms by which bile acids and sphingolipids regulate hepatic lipid metabolism. Dysregulation of bile acid and sphingolipid metabolism has been linked to steatosis, inflammation, and fibrosis in patients with NAFLD. This clinical observation has been recapitulated in animal models, which are well-accepted by experts in the hepatology field. Recent transcriptomic and lipidomic studies also show that sphingolipids are important players in the pathogenesis of NAFLD. Moreover, the identification of bile acids as activators of sphingolipid-mediated signaling pathways established a novel theory for bile acid and sphingolipid biology. In this review, we summarize the recent advances in the understanding of bile acid and sphingolipid-mediated signaling pathways as potential contributors to NAFLD. A better understanding of the pathologic effects mediated by bile acids and sphingolipids will facilitate the development of new diagnostic and therapeutic strategies for NAFLD.

Sphingolipids Profiling of Plasma in Patients with Diabetes Mellitus Associated with Atherosclerosis by a Novel Normal-Phase UPLC-QToF MS Method

A novel normal-phase UPLC-QToF MS method was developed for sphingolipids analysis,which was then applied to separate and identify seven classes of sphingolipids in plasma.The time-consuming of this novel method was much shorter than previous 2D LC–MS method,while the sensitivity,repeatability and resolution for sphingolipids analysis were better or comparable.Besides,the differences of lipids in human plasma among diabetes mellitus patients,diabetes mellitus associated with atherosclerosis patients and control subjects were also compared.Finally,12 sphingolipids species were identified as the amounts of which in diabetes mellitus associated with atherosclerosis patients were significantly higher than them in diabetes mellitus patients(VIP>1.0,p value<0.05,fold change>1.5).As the isomers of GalCs and GluCs were successfully separated,it was found that five GluCs,rather than GalCs,were included in these 12 potential biomarkers.These results suggest the need to separate GalCs from GluCs,and also indicated that there may be some extra activation pathways of diabetes mellitus associated with atherosclerosis,different from the atherosclerosis pathway and the diabetes mellitus pathway,causing cardiovascular disease.

Effects of excessive body fat on colostrum lipid patterns: overweight/obese vs. normal weight mothers

Prenatal overweight/obesity(OW/OB)can alter colostrum lipid patterns,thereby affecting the lipid metabolism and even the cognitive and healthy development of infants.However,studies on changes in colostrum lipids in the context of OW/OB are limited,particularly for glycerides and polar lipids.Therefore,this study investigated the infl uence of maternal prenatal weight on colostrum in lipid subclasses and molecular species.The concentration of triacylglycerols(TAGs)in the colostrum of the OW/OB group(35894.43 mg/L)was higher than that of the normal weight(NW)group(26639.20 mg/L),suggesting that colostrum from OW/OB mothers could provide more energy to their infants.Further analysis of the fatty acid composition of TAGs revealed that elevated maternal body weight enhanced the concentration of TAGs containing saturated or n-6 fatty acids and shortened the carbon number of TAGs.Docosahexaenoic acid(DHA)/arachidonic acid(AA)/choline-containing lipids,such as DHA-containing TAGs,AA/DHA-containing phosphatidylethanolamine,and choline-containing phospholipids,were present in higher levels in the colostrum of OW/OB mothers than NW mothers.However,the concentrations of palmitic acid-containing TAGs,linoleic acid-containing TAGs,dihomo-γ-linolenic acid-containing TAGs,and polar lipids and the ratio of TAGs containing n-6 fatty acid/n-3 fatty acid were signifi cantly higher in the colostrum of OW/OB mothers than in that of NW mothers.The fatty acid composition and sphingoid bases of sphingolipids were also altered due to elevated body weight.In conclusion,OW/OB affects colostrum lipids with respect to composition,concentration,and percentage.Although the colostrum of healthy OW/OB mothers can provide suffi cient DHA/AA/choline-containing lipids to their infants,normalization of body weight and fat reserves should be considered as a strategy for highquality human milk lipids.

Leech Poecilobdella manillensis protein extract ameliorated hyperuricemia by restoring gut microbiota dysregulation and affecting serum metabolites

BACKGROUND Hyperuricemia(HUA)is a public health concern that needs to be solved urgently.The lyophilized powder of Poecilobdella manillensis has been shown to significantly alleviate HUA;however,its underlying metabolic regulation remains unclear.AIM To explore the underlying mechanisms of Poecilobdella manillensis in HUA based on modulation of the gut microbiota and host metabolism.METHODS A mouse model of rapid HUA was established using a high-purine diet and potassium oxonate injections.The mice received oral drugs or saline.Additionally,16S rRNA sequencing and ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry-based untargeted metabolomics were performed to identify changes in the microbiome and host metabolome,respectively.The levels of uric acid transporters and epithelial tight junction proteins in the renal and intestinal tissues were analyzed using an enzyme-linked immunosorbent assay.RESULTS The protein extract of Poecilobdella manillensis lyophilized powder(49 mg/kg)showed an enhanced anti-trioxypurine ability than that of allopurinol(5 mg/kg)(P<0.05).A total of nine bacterial genera were identified to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder,which included the genera of Prevotella,Delftia,Dialister,Akkermansia,Lactococcus,Escherichia_Shigella,Enterococcus,and Bacteroides.Furthermore,22 metabolites in the serum were found to be closely related to the anti-trioxypurine activity of Poecilobdella manillensis powder,which correlated to the Kyoto Encyclopedia of Genes and Genomes pathways of cysteine and methionine metabolism,sphingolipid metabolism,galactose metabolism,and phenylalanine,tyrosine,and tryptophan biosynthesis.Correlation analysis found that changes in the gut microbiota were significantly related to these metabolites.CONCLUSION The proteins in Poecilobdella manillensis powder were effective for HUA.Mechanistically,they are associated with improvements in gut microbiota dysbiosis and the regulation of sphingolipid and galactose metabolism.

Identification prognostic features related to sphingolipid metabolism and experimental validation of TRIM47 in hepatocellular carcinoma

Background:The specific impact of sphingolipid metabolism on developing hepatocellular Carcinoma(HCC)remains unclear.This study aims to explore the relationship between sphingolipid metabolism and HCC prognosis,immune response,and drug sensitivity.Methods:Data were obtained from The Cancer Genome Atlas(TCGA)-Hepatocellular Carcinoma(LIHC)and Gene Expression Omnibus(GEO,GSE14520 datasets).47 sphingolipid metabolism genes were obtained from the Kyoto Encyclopedia of Genes and Genomes(KEGG)database.After classifying HCC samples using the Non-negative Matrix Factorization(NMF)clustering method,differentially expressed genes were screened.Then,8 risk genes were obtained by univariate analysis,survival random forest reduction and lasso analysis.The expression of 8 risk genes was verified in vitro.Results:8 risk genes were used to construct the Sphingolipid score model.High-Sphingolipid score predicted poor prognosis of HCC patients.Sphingolipid score was associated with immune checkpoints(IL-1B,TLR4,TGFB1,and IL-10),immune cells(Th2,Treg,MDSC,Neutrophil,Fibroblasts and macrophage),and MAPK Cascade.In the High-Sphingolipid score group,a significantly higher proportion of patients with TP53(p53)mutations was significantly higher(56%).Furthermore,patients with a high-Sphingolipid score were predicted to have a higher sensitivity to chemotherapy drugs.In vitro validation showed that compared with normal liver cells LX-2,TRIM47,and S100A9 significantly increased in liver cancer cells Hep G2,MHCC-97H,and Hep3B2.1-7,while SLC1A7,LPCAT1,and CFHR4 significantly decreased.Silencing TRIM47 reduced the proliferation and promoted apoptosis.The levels of ceramide synthesis-related indexes(CERS1,CERS6,CERS5,and SPTLC2)increased,and the ACER3 related to catalytic hydrolysis decreased.Conclusion:We constructed a sphingolipid metabolism-related prognostic signature(Sphingolipid score)based on 8 risk genes.TRIM47 may affect the development of liver cancer by regulating the relevant indicators of ceramide synthesis and catalytic hydrolysis.

Potential of traditional Chinese medicine lyophilized powder of Poecilobdella manillensis in the treatment of hyperuricemia

Traditional Chinese medicine has a long and illustrious history,and with the development of modern science and technology,the research and application of traditional Chinese medicines have continued to progress significantly.Many traditional Chinese medicinal herbs have undergone scientific validation,reinvi-gorating with new life and vitality,and contributing unique strengths to the advancement of human health.Recently,the discovery that leech total protein extracted from Poecilobdella manillensis lyophilized powder reduces blood uric acid(UA)levels by inhibiting the activity of xanthine oxidase to decrease UA synthesis and promotes UA excretion by regulating different UA transporters in the kidney and intestine has undoubtedly injected new vitality and hope into this field of research.The purpose of this editorial is to comment on this study,explore its strengths and weaknesses,and there is a hope to treat a range of metabolic-related syndromes,including hyperuricemia,by targeting the gut microbiota.

Involvement of sphingoid bases in mediating reactive oxygen intermediate production and programmed cell death in Arabidopsis

Sphingolipids have been suggested to act as second messengers for an array of cellular signaling activities in plant cells, including stress responses and programmed cell death （PCD）. However, the mechanisms underpinning these processes are not well understood. Here, we report that an Arabidopsis mutant, fumonisin B1 r_esistant11-1 （/br11-1）, which fails to generate reactive oxygen intermediates （ROIs）, is incapable of initiating PCD when the mutant is challenged by fumonisin B l （FB0, a specific inhibitor of ceramide synthase. Molecular analysis indicated that FBR11 encodes a long-chain base 1 （LCB 1） subunit of serine palmitoyltransferase （SPT）, which catalyzes the first rate-limiting step of de novo sphingolipid synthesis. Mass spectrometric analysis of the sphingolipid concentrations revealed that whereas the fbr11-1 mutation did not affect basal levels of sphingoid bases, the mutant showed attenuated formation of sphingoid bases in response to FBl. By a direct feeding experiment, we show that the free sphingoid bases dihydrosphingosine, phytosphingosine and sphingosine efficiently induce ROI generation followed by cell death. Conversely, ROI generation and cell death induced by dihydrosphingosine were specifically blocked by its phosphorylated form dihydrosphingosine- 1-phosphate in a dosedependent manner, suggesting that the maintenance of homeostasis between a free sphingoid base and its phosphorylated derivative is critical to determining the cell fate. Because alterations of the sphingolipid level occur prior to the ROI production, we propose that the free sphingoid bases are involved in the control of PCD in Arabidopsis, presumably through the regulation of the ROI level upon receiving different developmental or environmental cues.

New insights into renal lipid dysmetabolism in diabetic kidney disease

Lipid dysmetabolism is one of the main features of diabetes mellitus and manifests by dyslipidemia as well as the ectopic accumulation of lipids in various tissues and organs,including the kidney.Research suggests that impaired cholesterol metabolism,increased lipid uptake or synthesis,increased fatty acid oxidation,lipid droplet accumulation and an imbalance in biologically active sphingolipids(such as ceramide,ceramide-1-phosphate and sphingosine-1-phosphate)contribute to the development of diabetic kidney disease(DKD).Currently,the literature suggests that both quality and quantity of lipids are associated with DKD and contribute to increased reactive oxygen species production,oxidative stress,inflammation,or cell death.Therefore,control of renal lipid dysmetabolism is a very important therapeutic goal,which needs to be archived.This article will review some of the recent advances leading to a better understanding of the mechanisms of dyslipidemia and the role of particular lipids and sphingolipids in DKD.

Regulation of cancer cell migration and invasion by sphingosine-1-phosphate

Sphingosine-1-phosphate (S1P) is a bioactive sphingo-lipid that has been implicated in regulation of a number of cancer cell malignant behaviors, including cell proliferation, survival, chemotherapeutic resistance and angiogenesis. However, the effects of S1P on cancer cell migration, invasion and metastasis, are perhaps its most complex, due to the fact that, depending upon the S1P receptors that mediate its responses and the crosstalk with other signaling pathways, S1P can either positively or negatively regulate invasion. This review summarizes the effects of S1P on cancer cell invasion and the mechanisms by which it affects this important aspect of cancer cell behavior.

Regulatory role of sphingosine kinase and sphingosine-1-phosphate receptor signaling in progenitor/stem cells

Balanced sphingolipid signaling is important for the maintenance of homeostasis. Sphingolipids were demonstrated to function as structural components, second messengers, and regulators of cell growth and survival in normal and disease-affected tissues. Particularly, sphingosine kinase 1 (SphK1) and its product sphingosine-1-phosphate (S1P) operate as mediators and facilitators of proliferation-linked signaling. Unlimited proliferation (selfrenewal) within the regulated environment is a hallmark of progenitor/stem cells that was recently associated with the S1P signaling network in vasculature, nervous,muscular, and immune systems. S1P was shown to regulate progenitor-related characteristics in normal and cancerstemcells(CSCs) viaG-protein coupled receptorsS1Pn(n=1 to 5). The SphK/S1P axis is crucially involved in the regulation of embryonic development of vasculature and the nervous system, hematopoietic stem cell migration, regeneration of skeletal muscle, and development of multiple sclerosis. The ratio of the S1P receptor expression, localization, and specific S1P receptoractivated downstream effectors influenced the rate of selfrenewal and should be further explored as regeneration related targets. Considering malignant transformation,it is essential to control the level of self-renewal capacity.Proliferation of the progenitor cell should be synchronized with differentiation to provide healthy lifelong function of blood, immune systems, and replacement of damaged ordead cells. The differentiation-related role of SphK/S1P remains poorly assessed. A few pioneering investigations exploredpharmacologicaltoolsthattargetsphingolipid signaling and can potentially confine and direct self-renewal towards normal differentiation. Further investigation is required to test the role of the SphK/S1P axis in regulation of self-renewal and differentiation.

Obesity-associated steatotic liver exhibits aberrant or altered sphingolipid composition and preferentially accumulates ceramide species containing long chain fatty acids

The sphingolipid (SL) signaling pathways are induced by reactive oxygen species and proin-flammatory molecules, which are shown to be upregulated in the obese state. The present work was conducted to determine if an altered SL pathway exists, and contributes to the pathogenesis of hepatic steatosis associated with obesity. Steatotic and non-steatotic livers were procured from Zucker Obese female rats and their lean counterparts in this pre-clinical study, and assessed for enzymes involved in degradation as well as in phos-phorylation of proapoptotic SLs. The expression of enzymes [sphingo-myelinase (SMase), ceramidase, and sphingosine kinase-1 (SK1)] and apoptotic proteins (Bax and Bcl-2) was quantified by ELISA and by Western Blot. Sphingomyelin (SM), ceramide, ceramide-1 phosphate (C1P), sphingosine (SPH), and sphingosine-1-phosphate (S1P) levels were quantified by high-performance liquid chroma-tography (HPLC)-tandem mass spectroscopy (MS). Obese steatotic livers exhibited significantly upregulated ceramidase and down-regulated SK1 and C1P levels (P < 0.05), as well as significantly lower levels of SM and higher levels of ceramide species containing long chain fatty acids, compared to their lean counterparts. These findings demonstrate that obese liver harbours SLs that favour a proapoptotic environment. Moreover, accumulation of ceramides containing long chain fatty acids could be involved in the pathogenesis of hepatic steatosis.

Orosomucoid-like protein 3,rhinovirus and asthma

The genetic variants of orosomucoid-like protein 3(ORMDL3)gene are associated with highly significant increases in the number of human rhinovirus(HRV)-induced wheezing episodes in children.Recent investigations have been focused on the mechanisms of ORMDL3 in rhinovirus infection for asthma and asthma exacerbations.ORMDL3 not only regulates major human rhinovirus receptor intercellular adhesion molecule 1 expression,but also plays pivotal roles in viral infection through metabolisms of ceramide and sphingosine-1-phosphate,endoplasmic reticulum(ER)stress,ER-Golgi interface and glycolysis.Research on the roles of ORMDL3 in HRV infection will lead us to identify new biomarkers and novel therapeutic targets in childhood asthma and viral induced asthma exacerbations.

Advances on Current Techniques and Methodologies in Milk Lipidomics

Milk is a complex biological fluid containing lipids,proteins,carbohydrates and minerals,which are essential for infant growth.While the lipid portion constitutes only 3%-5%of the total milk composition,it accounts for over 50%of the infant’s daily energy intake.The dominant portion(approximately 98%)is in the form of triacylglycerols and polar lipids,such as glycerophospholipids and sphingolipids,forming minor components.Recently,with the development of lipidomics,important progresses have been made in milk lipidomics,and the identification and quantification of several milk lipids at the group and molecular species level has become a reality,thereby providing useful information for the infant formula industry.In this review,an overview of the separation of the main components of milk lipids was presented,including glycerolipids,phospholipids and sphingolipids.The analytical methods and strategies for milk lipidomics,including gas chromatography-mass spectrometry(MS),capillary electrophoresis MS,nuclear magnetic resonance,matrix-assisted laser desorption ionization-MS,electrospray ionization-MS,shotgun lipidomics and liquid chromatography-MS,were reviewed.Additionally,the bioinformatics of lipidomics for milk lipid determination,including lipid classification,lipid databases and lipid analysis software,were investigated.This review would aid future investigations of the nutrition of milk lipids and refined researches on formula milk powder.

Sphk1 Expression and Survival Outcomes in Squamous Cell Carcinoma of the Oral Cavity

Sphingosine kinase 1 (SphK1) is an important mediator of apoptosis and the proliferation of cancer cells. It is upregulated in cells showing increasing radioresistance. Here we present the correlation between SphK1 expression and survival outcomes in patients with carcinoma of the oral cavity. A retrospective chart review was performed between January 2009 and August 2010 at the University of Southern California. Patients diagnosed with an advanced-stage primary tumor restricted to the oral cavity and a minimum follow-up of two years were included. Patients who did not receive post-operative radiation therapy were excluded. Eighteen patients met the inclusion criteria with 10 (55.6%) patients demonstrating high expression of SphK1 and 8 (44.4%) patients demonstrating a low-to-moderate expression of SphK1. Tumor recurrence occurred in 9 patients (50.0%): 5 patients (27.8%) in the SphK1high cohort at a mean time to progression of 2.5 mo and 4 patients (22.2%) in the SphK1low cohort at a mean time to progression of 11.0 mo (p = 0.023). Death occurred in 8 patients (66.7%) in the SphK1high cohort and 3 patients (16.7%) in the SphK1low cohort (p = 0.036). Higher expression of SphK1 correlates with greater radioresistance and poorer survival outcomes in patients with HNSCC of the oral cavity.

Sphingosine 1-phosphate in inflammation

Sphingolipids are formed via the metabolism of sphingomyelin,aconstituent of the plasma membrane.or by denovosynthesis.Enzymatic pathways result in the formation of sevenal different lipid meiators,which are knowm to bave important roles in many elllar proceses.imcluding polfeatioe,apoptosis and migation Several studies nDowr suggest that these shingolipid mediators,inchding cenamide,ceramside i-pbosphate and sphingosine 1-pbosphate(SIP).are likely to have a integral role in infamation.This can involve,for example activation of po-inammatory transcription factors in different cell types and indiuction of cyloxygenase-2.leading t如o productio of pro-inamatory prostaglandins.The mode of action of each sphingolipid is different.Increased ceramide production leads to the formation of ceramide-rich areas of the membnane.which may assemble sigalling compleses,whereas SIP acts via b-affnity G-protein-coupled SIP receptors on the plasma membrane.Recent studies bave demonstated that in vitro efects of sphingolipids o infammation can translate into in vivo models.This review will higblight the areas of research where spbingolipids ae involved in infamomation and the mecharisms of acion of each mediator.In adirion,the therpeutic poternial of dinugs that alter sphingolipid actions mill be exmined with reference to disease states,such as asthma and infammatary bowel disease,which invove importanot ifmaxmsutory components.A signifcant body of research now indicates that sphingolipids ure intimately inolved in the infammatory process and recent studies have demonstated that these lipids.together with associated enzymes and receptors,can provide effective drug targets for the treatment of pathological inflammation.