Metabolismo de los esfingolípidos y su relación con las enfermedades cardiovasculares, renales y metabólicas / Sphingolipid metabolism and its relationship with cardiovascular, renal and metabolic diseases

Resumen Los esfingolípidos (esfingomielina, glucolípidos y gangliósidos) se localizan en las membranas celulares, el plasma y las lipoproteínas. En pacientes con enfermedades cardiovasculares, renales y metabólicas, el perfil de los esfingolípidos y sus metabolitos (ceramida, esfingosina y esfingosina-1-fosfato) se modifica, y estos cambios pueden explicar las alteraciones en algunas respuestas celulares, como la apoptosis. Además, se ha sugerido que la esfingosina y la esfingosina-1-fosfato previenen la COVID-19. En esta revisión también se mencionan brevemente las técnicas que permiten el estudio de los esfingolípidos y sus metabolitos.

Abstract Sphingolipids (sphingomyelin, glycolipids, gangliosides) are located in cell membranes, plasma, and lipoproteins. In patients with cardiovascular, renal, and metabolic diseases, the profile of sphingolipids and their metabolites (ceramide, sphingosine, and sphingosine-1-phosphate) is modified, and these changes may explain the alterations in some cellular responses such as apoptosis. Furthermore, sphingosine and sphingosine-1-phosphate have been suggested to prevent COVID-19. This review also briefly mentions the techniques that allow us to study sphingolipids and their metabolites.

Effect of FTY720 on transfusion-related acute lung injury: a preliminary investigation / 中国输血杂志

【Objective】 To investigate the effects and mechanisms of different doses of fingolimod (FTY720) on non-antibody-mediated transfusion-related acute lung injury (TRALI). 【Methods】 A TRALI mouse model was constructed using lipopolysaccharide (LPS) pre-stimulation and platelets (Plt) of different storage days for second strike. The success of the modeling was determined by protein concentration in lung tissue homogenates, myeloperoxidase (MPo) activity, lung wet/dry weight ratio (W/D ratio), lung tissue damage score and pathological sections. Ceramide and sphingosine-1-phosphate (S1P) contents in platelets of different storage days were detected. FTY720 was administered 1 h after LPS injection to investigate the role of FTY720 in TRALI. The expression levels of vascular endothelial cadherin (VE-cadherin) and zonula occludens-1 (ZO-1) were analyzed by WB. 【Results】 Mice infused with stored 5-day Plt (d5Plt group) exhibited typical signs of TRALI, and the differences in lung tissue homogenate protein concentration (6 546.38±409.50) μg/mL, MPO activity (49.38±4.43) U/L, W/D ratio 4.79±0.21, and lung tissue damage score 7.24±0.38 from the rest of the groups were statistically significant (P<0.05). With the increase of platelet storage time, the ceramide content gradually increased and S1P content gradually decreased, and the ratio of the two was imbalanced. d5Plt showed statistically significant differences (P<0.01) in ceramide content (58.37±5.69) μmol/L and S1P content (149.81±4.86) nmol/L from the rest of the groups. After preventive administration of FTY720, 1 mg/kg FTY720 had no significant effect on TRALI mice, whose lung tissue homogenate protein concentration (6 170.26±545.50) μg/mL, MPO activity (45.97±4.79) U/L, W/D ratio 4.88±0.25, and lung tissue damage score 7.92±0.65 were significantly higher than those of the normal and LPS control groups (P<0.01). The low-dose (0.5, 0.2, and 0.1 mg/kg) FTY720 group alleviated lung injury, and its protein concentration, MPO activity, W/D ratio, and lung tissue injury score were significantly lower than those of the d5Plt group (P<0.05). Pathological sections also showed similar results. In terms of endothelial intercellular junction protein expression, the VE-cadherin expression levels in the 1 mg/kg FTY720 group were significantly lower than those in the normal and LPS control groups (P<0.05), and the VE-cadherin and ZO-1 expression levels in the low-dose (0.5, 0.2, and 0.1 mg/kg) FTY720 group were significantly higher than those in the d5Plt group (P<0.05), which tended to be normalized. 【Conclusion】 In this study, a TRALI mouse model was successfully established by one strike of LPS and two strikes of d5Plt. Low doses of FTY720 (0.5, 0.2, 0.1 mg/kg) were protective against TRALI, while high doses of FTY720 (1 mg/kg) may aggravate the symptoms of TRALI. This protective effect may be somewhat dependent on the expression of VE-cadherin and ZO-1.

Development and validation of an LC-MS/MS method for the determination of 12 ceramides in human plasma / 中华检验医学杂志

Objective:To establish and validate a reliable and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the detection of 12 ceramides in human plasma.Methods:From October 2021 to October 2022, 438 apparently healthy individuals were enrolled in the Affiliated Hospitals of Zunyi Medical University for reference intervals of 12 ceramides in this population. Plasma samples were collected, and separated using the ACQUITY UPLC BEH C18 (2.1×50 mm, 1.7 μm) column, deuterated isotopes were used as internal standards. The mobile phase is water (containing 0.1% formic acid) and isopropanol: acetonitrile (1∶1, v/v, containing 0.1% formic acid) at a flow rate of 0.4 ml/min with gradient elution. The detection method was established using the Qlife Lab 9000 Plus triple quadrupole mass spectrometer. The performance of the method was evaluated in terms of linearity, the lower limit of quantification, precision, recovery, and stability.Results:The method passed the performance evaluation in terms of linearity, the lower limit of quantification, recovery, precision, and stability. The intra-and inter-batch precision of the 12 ceramides ranged from 1.3% to 14.3%, the correctness was verified by spiked recovery experiments, and the recoveries ranged from 91.9% to 111.0%. The lower limit of quantification ranged from 0.001 to 0.100 μmol/L. Standard curve showed good linearity (correlation coefficient r>0.990). Stability tests showed that the 12 ceramides were stable in the biological matrix and after processing under different conditions for a specified period of time. The corresponding biological reference intervals were established for each of the 12 ceramides: 0.103-0.326 μmol/L for Cer(d18∶1/16∶0), 0.018-0.098 μmol/L for Cer(d18∶1/18∶0), 0.933-3.919 μmol/L for Cer(d18∶1/24∶0), 0.243-1.072 μmol/L for Cer(d18∶1/24∶1), 0.001-0.007 μmol/L for Cer(d18∶1/14∶0), 0.022-0.095 μmol/L for Cer(d18∶1/20∶0), 0.185-0.835 μmol/L for Cer(d18∶1/22∶0), 0.003-0.022 μmol/L for Cer(d18∶0/16∶0), 0.001-0.016 μmol/L for Cer(d18∶0/18∶0), 0.017-0.156 μmol/L for Cer(d18∶0/24∶0), 0.008-0.074 μmol/L for Cer(d18∶0/24∶1), and 0.106-0.721 μmol/L for LacCer(d18∶1/24∶1). Conclusion:Our study shows that the newly established LC-MS/MS method for the determination of 12 ceramides in human plasma is reliable, and suitable for clinical application.

Endocannabinoids are potential inhibitors of glioblastoma multiforme proliferation / 中西医结合学报

Globally, it is evident that glioblastoma multiforme (GBM) is an aggressive malignant cancer with a high mortality rate and no effective treatment options. Glioblastoma is classified as the stage-four progression of a glioma tumor, and its diagnosis results in a shortened life expectancy. Treatment options for GBM include chemotherapy, immunotherapy, surgical intervention, and conventional pharmacotherapy; however, at best, they extend the patient's life by a maximum of 5 years. GBMs are considered incurable due to their high recurrence rate, despite various aggressive therapeutic approaches which can have many serious adverse effects. Ceramides, classified as endocannabinoids, offer a promising novel therapeutic approach for GBM. Endocannabinoids may enhance the apoptosis of GBM cells but have no effect on normal healthy neural cells. Cannabinoids promote atypical protein kinase C, deactivate fatty acid amide hydrolase enzymes, and activate transient receptor potential vanilloid 1 (TRPV1) and TRPV2 to induce pro-apoptotic signaling pathways without increasing endogenous cannabinoids. In previous in vivo studies, endocannabinoids, chemically classified as amide formations of oleic and palmitic acids, have been shown to increase the pro-apoptotic activity of human cancer cells and inhibit cell migration and angiogenesis. This review focuses on the biological synthesis and pharmacology of endogenous cannabinoids for the enhancement of cancer cell apoptosis, which have potential as a novel therapy for GBM. Please cite this article as: Duzan A, Reinken D, McGomery TL, Ferencz N, Plummer JM, Basti MM. Endocannabinoids are potential inhibitors of glioblastoma multiforme proliferation. J Integr Med. 2023; 21(2): 120-128.

LASS2/TMSG1 overexpression inhibits proliferation and promotes apoptosis of human lung cancer A549 cells possibly by upregulating ceramide and p38 MAPK to activate a signaling cascade / 南方医科大学学报

OBJECTIVE@#To investigate the effects of LASS2/TMSG1 gene overexpression on proliferation and apoptosis of human lung cancer A549 cells and explore the possible mechanism.@*METHODS@#We examined LASS2/TMSG1 expression level in a previously constructed A549 cell line overexpressing LASS2/TMSG1 using Western blotting. The proliferation and apoptosis of the cells were detected using colony-forming assay, CCK-8 assay, Hoechst/PI double staining and flow cytometry. Fourteen nude mice were randomized into 2 groups (n=7) to receive subcutaneous injection of A549 cells with or without LASS2/TMSG1 overexpression on the back of the neck, and the cell proliferation in vivo was observed. The expression levels of p38 MAPK protein and p-p38 MAPK protein in the xenografts were detected with Western blotting. ELISA was used to detect the levels of ceramide and p38 MAPK protein in cultured A549 cell supernatants and the xenografts in nude mice.@*RESULTS@#Compared with the negative control cells, A549 cells with LASS2/TMSG1 overexpression had significantly lowered proliferation ability in vitro with increased early apoptosis rate (P < 0.05), and showed obvious growth inhibition after inoculation in nude mice(P < 0.05). Western blotting showed that in both cultured A549 cells and the xenografts in nude mice, LASS2/TMSG1 gene overexpression significantly increased the expression levels of p38 MAPK protein and p-p38 MAPK protein (P < 0.05); the results of ELISA also revealed significantly increased levels of ceramide and p38 MAPK protein in the cell supernatant andxenografts as well (P < 0.05).@*CONCLUSION@#Overexpression of LASS2/TMSG1 gene can significantly inhibit the proliferation and promote early apoptosis of human lung cancer A549 cells both in vitro and in vivo possibly by upregulating the expressions of ceramide and p38 MAPK protein to activate a signal transduction cascade.

CERKL attenuates blue light-induced oxidative stress in human retinal pigment epithelial cells by activating the SIRT1/E2F1 axis / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate whether ceramide kinase-like protein(CERKL)alleviates oxidative stress injury of retinal pigment epithelial(RPE)cells induced by blue light via activating the silent information regulator 1(SIRT1)/E2F transcription factor 1(E2F1)axis. METHODS:Cultured human retinal pigment epithelial-19(ARPE-19)cells were irradiated with blue light to observe the morphological changes, and the expression of CERKL was detected by PCR and Western blot. ARPE-19 cells were transfected with siRNA-CERKL and pcDNA3.1-CERKL respectively. After exposure to blue light, cell viability was determined by MTT assay, apoptosis was detected by TUNEL assay, content of oxidative stress markers and the expression of SIRT1/E2F1 axis was analyzed. Then siRNA-SIRT1 was transfected into ARPE-19 cells, and the oxidative stress damage of ARPE-19 cells under blue light irradiation was detected again.RESULTS:ARPE-19 cells gradually contracted into spheres and appeared vacuoles after exposure to blue light. Blue light irradiation led to the increase of CERKL expression level(P<0.05), meanwhile, the rate of cell viability was decreased(P<0.05), the rate of the apoptosis was increased(P<0.05), contents of reactive oxygen species, malondialdehyde and 8-hydroxydeoxyguanosine were increased(P<0.05). Silence of CERKL aggravated this phenomenon, while up-regulation of CERKL could alleviate this change(P<0.05). Up-regulation of CERKL also activated the expression of SIRT1 and promoted the deacetylation of E2F1(P<0.05). Silencing SIRT1 could reverse the alleviating effect of up-regulating CERKL on oxidative stress injury of ARPE-19 cells induced by blue light(P<0.05). CONCLUSION: CERKL can reduce oxidative stress damage of ARPE-19 cells induced by blue light via activating SIRT1 expression and promoting the deacetylation of E2F1.

A Comparative Study of Licochalcone A Moisturiser versus Topical Hydrocortisone in Treating Mild-to-Moderate Atopic Dermatitis

Background@#Topical corticosteroids are the mainstay of treatment for patients with atopic dermatitis. However, adverse effects associated with long-term steroid use often limit its use. This interventional study compared the efficacy of a proprietary moisturiser containing licochalcone A, omega-6 fatty acids, and ceramide 3 against 1% hydrocortisone cream in treating patients with mild-to-moderate atopic dermatitis.@*Methods@#Patients with mild-to-moderate atopic dermatitis affecting either the cubital fossa or popliteal fossa symmetrically were given twice-daily applications of the moisturiser and hydrocortisone on opposite sides of the body and monitored for a total of three weeks in a non-randomised half body, doubleblind study. Hydrocortisone was switched to aqueous cream after two weeks, whereas the application of the moisturiser continued until study completion. The assessment of SCORing Atopic Dermatitis (SCORAD) index and Dermatology Life Quality index was performed at baseline and every subsequent follow-up visit to measure patients’ response to treatment. @*Results@#The licochalcone A (LA) moisturiser and 1% hydrocortisone (HC) cream both demonstrated significant reduction in sign and symptom scores after only 1 week of treatment (percentage of reduction in sign and symptom scores: 52.8% [LA] vs 58.5% [HC]). Further reduction in mean sign and symptom scores for both treatments was observed at week 2 (61.3% [LA] vs 56.8% [HC]) and also at week 3 when HC was switched to aqueous cream (70.5% [LA] vs 63.5% [HC→aqueous cream]) (p<0.001 vs baseline within the same treatment arm at weeks 1, 2 and 3). When comparing the mean difference in SCORAD index for both individual as well as total skin signs and symptoms between LA and HC (i.e. inter-arm comparison), there was no significant difference between the two treatments for all the assessed parameters. Patients reported improvements in itching, sleeplessness, and overall quality of life over the course of treatment.@*Conclusion@#The licochalcone A moisturiser can be considered as an effective steroid-sparing alternative to topical corticosteroids in managing mild-to-moderate atopic dermatitis.

The correlation between bisphenol A exposure and ceramide as well as serum tumor markers in colorectal cancer / 中华疾病控制杂志

Objective The aim is to investigate the correlation between bisphenol A (BPA) exposure and tumor tissue ceramide (Cer) as well as serum tumor markers in colorectal cancer (CRC). Methods The morning urine and CRC tumor tissue were collected from 84 patients with CRC. The concentration of urine BPA was determined by liquid chromatography-mass spectrometer (LC-MS), urine BPA concentration was corrected with creatinine (Cr). Cer concentration of CRC tumor tissue was detected by Enzyme-linked immunosorbent assay (ELISA). The correlations of urine BPAcr, Cer content of CRC tumor tissue and tumor markers were analyzed. Results Cer content in CRC tumor tissue was positively correlated with BPAcr (r=0.784, P＜0.001). Regression analysis showed that the regression coefficient of Cer content in CRC tumor tissue and BPAcr was 0.218 (95% CI: 0.18-0.26), which was statistically significant (P＜0.001). There were significantly differences in CRC tumor tissue Cer and urine BPAcr between the CEA positive and negative groups, CA125 positive and negative groups, and CA19-9 positive and negative groups (all P<0.05), while there was no significant difference between AFP positive and negative groups in CRC tumor tissue Cer and urine BPAcr (P=0.247). Serum CEA, CA125 and CA19-9 were positively correlated with urine BPAcr (r values were 0.348, 0.251, 0.281, respectively, all P＜0.05) and Cer content in CRC tumor tissue (r values were 0.265, 0.309, 0.263, respectively, all P＜0.05). Conclusions BPA exposure may cause an increase of Cer in CRC tumor tissue and abnormalities in serum tumor markers, suggesting that BPA exposure may participate in the development and occurance of CRC by affecting the metabolism of Cer in CRC tumor tissue.

Effects of artesunate on the inhibition of hepatic fibrosis through ceramide synthase-ceramide pathway / 中国应用生理学杂志

To investigate the effects of ceramide pathway on the inhibition of artesunate (Art) to hepatic fibrosis. LX-2 cells were divided into control group, Art treated group with 350 μmol/L, fumonisin B1 (FB1) treated group with 6 μmol/L, and Co-administration group of artesunate 350 μmol/L and fumonisin B1 6 μmol/L. There were 7 compound holes in each group. After 24 hours of treatment, the cells and supernatant were collected and detected. The expressions of homo sapiens longevity assurance homologue 2 (LASS2), peroxisome proliferators-activated receptors-γ (PPAR-γ) and Caspase-3 were evaluated by Western blot, the content of ceramide was evaluated by HPLC-FLD method, MTT assay was adopted to measure the rate of proliferation of LX-2 cells. The content of hydroxyproline was determined by digestive method. Compared with the control group, the expression of ceramide synthase protein and the ceramide content were increased significantly, the proliferation of LX-2 cells was inhibited significantly, the expressions of PPAR-γ and Caspase-3 protein were up-regulated and the secretion of hydroxyproline was inhibited in Art treated group (P＜0.05). In FB1 treated group, the protein expression of ceramide synthase and the ceramide content were decreased significantly, the proliferation of LX-2 cells was increased significantly, the expressions of PPAR-γ and Caspase-3 protein were down-regulated, and the secretion of hydroxyproline was increased (P＜0.05). Compared with the Art alone group, the combination of the two drugs could significantly reduce the effects of Art on the expression of ceramide synthase protein and the increase of ceramide content, and attenuate the effects of Art on the cell proliferation , PPAR-γ, Caspase-3 protein expression and hydroxyproline level of LX-2 cells (P＜0.05). Artesunate could inhibit hepatic fibrosis by increasing the content of ceramide through the ceramide synthase-ceramide pathway.

Fuzi Polysaccharide Inhibits Vascular Smooth Muscle Cell Calcification via Ceramide Signaling / 中山大学学报(医学科学版)

@#【Objective】The aim of this study is to investigate whether Fuzi polysaccharide（FPS）inhibits calcification of vascular smooth muscle cells（VSMC）and its underlying mechanism involving ceramide signaling.【Methods】We used Ox- LDL to induce in vitro model of human VSMC calcification in this study. FPS at different concentrations was used to treat human VSMC. Cell calcification was assessed by alizarin red staining. The mRNA expressions of osteogenic differentiation markers including Msx2，Osterix and BMP2，and contractile marker SMA were analyzed by qRT- PCR. The protein expressions of Msx2 and BMP2 were analyzed by western blot. Cell apoptosis was examined by TUNEL. Additionally，we investigated the effect of FPS on ceramide levels and N- SMase activity in VSMC. 【Results】We found that FPS inhibits Ox- LDL- induced VSMC apoptosis and calcification. Ceramide participates in Ox- LDL- induced apoptosis and calcification of VSMC. FPS reduces N- SMase activity and ceramide levels in Ox- LDL- treated VSMC. Collectively ， reducing N-SMase activity and ceramide levels could become a promising strategy for the treatment of vascular calcification.【Conclusion】We demonstrate that FPS attenuates VSMC calcification via targeting ceramide signaling.

Development of a Label-Free LC-MS/MS-Based Glucosylceramide Synthase Assay and Its Application to Inhibitors Screening for Ceramide-Related Diseases

Ceramide metabolism is known to be an essential etiology for various diseases, such as atopic dermatitis and Gaucher disease. Glucosylceramide synthase (GCS) is a key enzyme for the synthesis of glucosylceramide (GlcCer), which is a main ceramide metabolism pathway in mammalian cells. In this article, we developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to determine GCS activity using synthetic non-natural sphingolipid C8-ceramide as a substrate. The reaction products, C8-GlcCer for GCS, could be separated on a C18 column by reverse-phase high-performance liquid chromatography (HPLC). Quantification was conducted using the multiple reaction monitoring (MRM) mode to monitor the precursor-to-product ion transitions of m/z 588.6 → 264.4 for C8-GlcCer at positive ionization mode. The calibration curve was established over the range of 0.625–160 ng/mL, and the correlation coefficient was larger than 0.999. This method was successfully applied to detect GCS in the human hepatocellular carcinoma cell line (HepG2 cells) and mouse peripheral blood mononuclear cells. We also evaluated the inhibition degree of a known GCS inhibitor 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) on GCS enzymatic activity and proved that this method could be successfully applied to GCS inhibitor screening of preventive and therapeutic drugs for ceramide metabolism diseases, such as atopic dermatitis and Gaucher disease.

Research Progress of Periploca forrestii Schltr / 中国药学杂志

Periploca forrestii, a traditional medicine commonly used by Miao people, is one of the "three treasures of Miao medicine", which mainly contains various components such as cardiac glycosides, flavonoids, ceramides, terpenoids, phenylpropanoid and volatile oils. It has significant pharmacological effects including cardiotonic, anti-inflammatory, antioxidant, pain-suppressing, and antibacterial activities, and is used to treat rheumatoid arthritis, bruises, stomach pain, dyspepsia, amenorrhea, and dysentery. Relevant domestic and abroad literatures were summarized, and a comprehensive review of the chemical constituents, pharmacological effects, clinical application, quality control and spectrum-effect relationship of Periploca forrestii was conducted, to provide evidences for further investigation of Periploca forrestii Schltr.

Enrichment of Short-Chain Ceramides and Free Fatty Acids in the Skin Epidermis, Liver, and Kidneys of db/db Mice, a Type 2 Diabetes Mellitus Model

Patients with diabetes mellitus (DM) often suffer from diverse skin disorders, which might be attributable to skin barrier dysfunction. To explore the role of lipid alterations in the epidermis in DM skin disorders, we quantitated 49 lipids (34 ceramides, 14 free fatty acids (FFAs), and cholesterol) in the skin epidermis, liver, and kidneys of db/db mice, a Type 2 DM model, using UPLC-MS/MS. The expression of genes involved in lipid synthesis was also evaluated. With the full establishment of hyperglycemia at the age of 20 weeks, remarkable lipid enrichment was noted in the skin of the db/db mice, especially at the epidermis and subcutaneous fat bed. Prominent increases in the ceramides and FFAs (>3 fold) with short or medium chains (

Effect of desipramine on apoptosis and endoplasmic reticulum stress in atherosclerotic plaque of rabbits / 中国药理学通报

Aim: To investigate the effect of desipramine (DES) on apoptosis and endoplasmic reticulum stress(ERS) in atherosclerotic model of rabbits. Methods: The rabbit model of atherosclerosis (AS) was established through abdominal aorta balloon injury and high fat diets for 12 weeks. They were divided into high-fat diet(HFD) group and HFD + DES group randomly. The same numbers of healthy rabbits with chow diet were divided randomly into normal control (NC) group and DES group. All interventions were given for the last 4 weeks. At the end of week 12, serum lipid was tested by conventional method. Plasma ox-LDL was measured by ELISA. Plasma and arterial acid sphingomyelinase(ASM) activity and ceramide levels were detected by UPLC analysis. Cell apoptosis in abdominal aorta was measured by TUNEL staining. Expression of GRP78 and CHOP proteins were detected by Western blot. Results: On the one hand, DES had no effect on serum lipid profiles including TG, TC, HDL-C.LDL-C and ox-LDL levels compared with either healthy or atherosclerosis rabbits. On the other hand, DES inhibited ASM and ceramide levels both in plasma and aorta, and decreased apoptotic cells and proteins of GRP78 and CHOP expression in abdominal aorta. Conclusions: DES attenuates AS via inhibition of ASM, down-regulating ceramide, attenuating ERS and thus reducing the apoptosis of AS plaques.

Quantitative analysis of ceramides by ultrahigh-performance liquid chromatography tandem mass spectrometry / 上海交通大学学报（医学版）

Objective • To develop a method that can quantitatively analyze a wide range of ceramides with high throughout, sensitivity and accuracy. Methods • Ultrahigh-performance liquid chromatography tandem triple-quadrupole mass spectrometry (UHPLC-MS) was employed for quantitative analysis of 14 ceramides by using ZORBAX Eclipse plus C8 (2.1 mm×150 mm, 1.8 μm) column. Solvent A consisted of water, solvent B consisted of methanol, and 2.5 mmol/L ammonium acetate was added to both. Multiple reaction monitoring (MRM) mode and positive ion mode were used to analyze the ceramides. Results • This method can quantitatively analyze 14 ceramides in 10 minutes with the limit of detection (LOD) and limit of quantification (LOQ) between 0.06-0.42 nmol/L and 0.17-1.26 nmol/L, respectively. The accuracy ranged from 73.02% to 122.39%, and the relative standard deviation (RSD) of retention time and peak area were between 0.07%-0.54% and 2.26%-13.98%, respectively. Conclusion • Quantitative analysis of ceramides based on UHPLC-MS has high sensitivity, reproducibility and efficiency, which can be used to analyze the ceramides in biological samples such as cells.

The role of ceramide in radiation-induced bystander effect on germ cells in Caenorhabditis elegans / 中华放射医学与防护杂志

Objective To investigate the role of ceramide in radiation induced bystander effect (RIBE) in vivo by irradiating Caenorhabditis elegans with proton microbeam.Methods The posterior pharynx of wide-type N2 and genetically mutated L4-staged worms was irradiated with 2 000 particles,then germ cell apoptosis and gene expression were analyzed.Results Point-fixed radiation to posterior pharynx of N2 worms significantly increased the number of apoptotic germ cells (t =9.007,P＜0.05),but not in the worms with deletion mutants of ceramide synthase (CerS) genes (hyl-1 and lagr-1) (P＞0.05).Realtime quantitative PCR assay indicated that in both N2 and lagr-1 (gk327);hyl-1 (ok976) worms,the genes of egl-1 and ced-13 in core apoptosis pathway were up-regulated after radiation to posterior pharynx,without statistical significance between these two strains (P＞0.05).The gene expression levels of hyl-1 and lagr-1 were increased in both N2 and hus-1 (op241) worms after radiation with no statistical significant difference between two strains (P＞0.05).Furthermore,radiation-induced germ cell apoptosis was increased in abl-1 (ok171) worms (t=13.241,P＜0.05),rather than in lagr-1(gk327);hyl-1(ok976);abl-1(ok171) worms (t=13.462,P＜0.05).Conclusions Ceramide is required for RIBE on germ cell apoptosis in C.elegans,and it might play function together with egl-1 and ced-13 in core apoptosis pathway and HUS-1 in DNA damage response pathway.But ceramide had antagonistic relationship with anti-apoptotic protein abl-1 in germ cell apoptosis.

Effects of resveratrol on levels of ceramide via regulating miRNA-122 in treating non-alcoholic fatty liver disease / 中国病理生理杂志

AIM: To observe the therapeutical effects of resveratrol on non-alcoholic fatty liver disease and its potential mechanism.METHODS: Male C57BL/6J mice were fed with high-fat and high-cholesterol diet to established non alcoholic fatty liver disease model, and were administrated with resveratrol at doses of 80 mg/kg and 160 mg/kg.After 4-week treatment, the blood sample was collected for determination of total cholesterol (TC) and triglyceride (TG).The liver tissues were harvested for measuring the liver lipid content.The histopathological examination were conducted with hematoxylin and eosin staining.The ceramide levels in the liver tissues were detected by HPLC-MS.The microRNA (mi-RNA)-122 levels in the liver tissues were detected by real-time PCR.The protein levels of serine palmitoyltransferase (SPT) were determined by Western blot.The HepG2 cells were cultured and divided into 5 groups: control group, model group (induced by 0.25 mmol/L oleic acid), model+resveratrol group (treated with 5 μmol/L resveratrol), miRNA-122 siRNA group and resveratrol+miRNA-122 siRNA group.Except control group, the cells in other groups were stimulated with oleic acid and incubated with respective drugs simultaneously for 24 h.The levels of TC, TG and ceramide in the cells of each group were measured.The protein levels of SPT in each group were determined by Western blot.RESULTS: In non-alcoholic fatty liver disease mice, resveratrol dose-dependently reduced the serum TC and TG levels, decreased the lipid deposition, the ceramide level and the SPT protein level, and increased the level of miRNA-122 in the liver tissues.In the in vitro study, compared with model group, resveratrol reduced the serum TC and TG levels, decreased the ceramide level, reduced the SPT protein level.Compared with control group, the levels of TC, TG and ceramide, and the protein expression of SPT were increased in miRNA-122 siRNA group.Compared with miRNA-122 siRNA group, no statistical difference of TC, TG, ceramide and protein expression of SPT in resveratrol combined miRNA-122 siRNA group was observed.CONCLUSION: Resveratrol significantly reduces lipid accumulation by reduction of miRNA-122 and ceramide levels, and decrease in SPT protein levels in the liver.

Soft coral Cespitularia stolonifera: New cytotoxic ceramides and gastroprotective activity / 中国天然药物

In the present study, a new ceramide, namely 2S, 3R-4E, 8E-2-(heptadecanoylamino)-heptadeca-4, 8-diene-1, 3-diol (1), along with four known steroids, including 24-methylcholesta-5, 24(28)-diene-3β-ol (2), 24-methylcholesta-5, 24(28)-diene-3β-acetate (3), 4-methyl-24-methylcholesta-22-ene-3-ol (4), and cholesterol, was isolated and characterized from CHCl/MeOH extract of Cespitularia stolonifera. A new acetate derivative of compound 1, termed 2S, 3R-4E, 8E-2-(heptadecanoylamino)-heptadeca-4, 8-diene-1, 3-diacetate (1a), was also prepared in the present study. All the structures were established on the basis of modern spectroscopic techniques, including FT-IR, 1D, 2D-NMR, HRESI-MS, and GC-MS, in addition of chemical methods. (-)-Alloaromadendren, ledane, (1)-alloaromadendren oxide, isoaromadendrene epoxide and (-)-caryophellen oxide were identified from the n-hexane fraction using GC-MS. The extract and the two ceramides (1) and (1a) exhibited significant cytotoxic activity against lung cancer A549 cells, while the extract and the two steroids (2) and (3) exhibited significant cytotoxic activity against breast cancer MCF-7 cells. The CHCl/MeOH extract exhibited significant antiulcer activity in both ethanol and acetic acid induced ulcer models in rats, as evidenced by histopathological, histochemical, and biochemical examinations.

The influence of CM pathway AEA in human glioma U251 cell proliferation and apoptosis / 国际检验医学杂志

Objective To investigate the role of ceramide pathway in cell proliferation and early apoptosis induction in U251 glioma cell after cannabinoid receptora agent anandmide(AEA)treatment.Methods U251 gliom cells were treated with AEA(1-10 μmol/L),Ceramide(5-20 μmol/L) and fumonisin B1 (FB1) (10 μmol/L) pretreatment.The growth inhibition rate of U251 was investigated by MTT assay.The early events of the apoptosis were measured by flow cytometry using annexin-V/propium iodide(PI) double staining method.Results Different concentrations of AEA inhibited the proliferation of human glioma U251 cells,and had synergistic effect with CM by FB1(10 μmol/L)pretreatment for 24 h.After exposure to AEA(10 μmol/L)for 24 h,U251 gliomacells could undergo the early cell apoptosis which was affected by FB1(10 μmol/L).Conclusion AEA through the CM de novo synthesis pathway,and CM concentration was lazy in collaboration,thus inhibiting human glioma U251 cell proliferation and induce early apoptosis.

Associations among plasma vitamin C, epidermal ceramide and clinical severity of atopic dermatitis

BACKGROUND/OBJECTIVES: Atopic dermatitis (AD), a chronic inflammatory skin disease, is accompanied by disruption of the epidermal lipid barrier, of which ceramide (Cer) is the major component. Recently it was reported that vitamin C is essential for de novo synthesis of Cer in the epidermis and that the level of vitamin C in plasma is decreased in AD. The objective of this study was to determine the associations among clinical severity, vitamin C in either plasma or epidermis, and Cer in the epidermis of patients with AD. SUBJECTS/METHODS: A total of 17 patients (11 male and 6 female) aged 20-42 years were enrolled. The clinical severity of AD was assessed according to the SCORAD (SCORing Atopic Dermatitis) system. Levels of vitamin C were determined in plasma and biopsies of lesional epidermis. Levels of epidermal lipids, including Cer, were determined from tape-stripped lesional epidermis. RESULTS: The clinical severity of patients ranged between 0.1 and 45 (mild to severe AD) based on the SCORAD system. As the SCORAD score increased, the level of vitamin C in the plasma, but not in the epidermis, decreased, and levels of total Cer and Cer2, the major Cer species in the epidermis, also decreased. There was also a positive association between level of vitamin C in the plasma and level of total Cer in the epidermis. However, levels of epidermal total lipids including triglyceride, cholesterol, and free fatty acid (FFA) were not associated with either SCORAD score or level of vitamin C in the plasma of all subjects. CONCLUSIONS: As the clinical severity of AD increased, level of vitamin C in the plasma and level of epidermal Cer decreased, and there was a positive association between these two parameters, implying associations among plasma vitamin C, epidermal Cer, and the clinical severity of AD.