S1PR1 serves as a viable drug target against pulmonary fibrosis by increasing the integrity of the endothelial barrier of the lung

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with unclear etiology and limited treatment options. The median survival time for IPF patients is approximately 2-3 years and there is no effective intervention to treat IPF other than lung transplantation. As important components of lung tissue, endothelial cells (ECs) are associated with pulmonary diseases. However, the role of endothelial dysfunction in pulmonary fibrosis (PF) is incompletely understood. Sphingosine-1-phosphate receptor 1 (S1PR1) is a G protein-coupled receptor highly expressed in lung ECs. Its expression is markedly reduced in patients with IPF. Herein, we generated an endothelial-conditional S1pr1 knockout mouse model which exhibited inflammation and fibrosis with or without bleomycin (BLM) challenge. Selective activation of S1PR1 with an S1PR1 agonist, IMMH002, exerted a potent therapeutic effect in mice with bleomycin-induced fibrosis by protecting the integrity of the endothelial barrier. These results suggest that S1PR1 might be a promising drug target for IPF therapy.

Research progress of sphingosine kinase and sphingosine-1-phosphate (S1P) /S1P receptor signaling in tumor microenvironment / 药学学报

Sphingosine kinase (SphK), sphingosine-1-phosphate (S1P) and S1P receptor (S1PR) are involved in the tumor biological processes such as tumor cell proliferation and migration, and play an important role in the development of cancer. In recent years, researchers have increasingly focused on the interaction between cancer cells and the tumor microenvironment. The tumor microenvironment is genetically stable and can be induced to an antitumor phenotype, which has significant therapeutic advantages. Studies have shown that SphK/S1P/S1PR can regulate multiple aspects of the tumor microenvironment. This review summarizes the effects of SphK and S1P/S1PR signaling on the tumor microenvironment from four perspectives: tumor immune microenvironment, cancer associated fibroblasts, tumor angiogenesis and tumor hypoxic microenvironment, and also outlines potential drug research related to these signal molecules, aiming to elucidate the role of SphK/S1P/S1PR in tumor occurrence and development and provide new ideas for the research of anti-tumor drugs.

The S1P1 regulator IMMH002 and its therapeutic effect and mechanism on autoimmune hepatitis / 药学学报

This study assessed and explored the pharmacological effects and mechanisms of action of IMMH002 {2-amino-2-(2-(4ʹ-(2-ethyloxazol-4-yl)-[1,1ʹ-biphenyl]-4-yl)ethyl)propane-1,3-dio}, a selective sphingosine-1-phosphate receptor subtype 1 (S1P1) modulator, in a concanavalin A (ConA)-induced autoimmune hepatitis (AIH) mouse model. The experimental protocol strictly adhered to the guidelines of the Ethics Committee for Animal Research of the Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College (Approval No.: 00004046). Male ICR mice were pre-treated with the drug for four days, followed by induction of AIH through tail vein injection of ConA protein. Liver function, hepatic tissue pathology, peripheral blood parameters, as well as immunoglobulin G (IgG), inflammatory cytokines, T cell distribution, and inflammatory pathways were evaluated in mice. Results demonstrated that IMMH002 significantly reduced liver function indicators such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST), alleviated hepatic tissue inflammation and necrotic damage, decreased serum IgG levels, and lowered the expression of inflammatory mediators including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and interferon γ (IFN-γ). Additionally, it facilitated T lymphocyte homing, downregulated the phosphorylation of nuclear factor kappa-B (NF-κB), IκB kinase β (IKKβ) and nuclear factor inhibitor protein-α (IκBα) proteins in hepatic tissue and cellular inflammation models. Collectively, IMMH002 effectively ameliorated ConA-induced autoimmune hepatitis in mice, exhibiting extensive anti-inflammatory and anti-necrotic effects, thereby laying a theoretical foundation for AIH clinical treatment.

Role of S1PR1 in dorsal root ganglion in remifentanil-induced hyperalgesia in rats with incisional pain / 中华麻醉学杂志

Objective:To evaluate the role of sphingosine-1-phospho-1 receptor(S1PR1)in the dorsal root ganglion in remifentanil-induced hyperalgesia in rats with incisional pain.Methods:Forty-eight male Sprague-Dawley rats with successful intrathecal and caudal vein catheterization, weighing 260-280 g, aged 2-3 months, were divided into 6 groups ( n= 8 each) using a random number table method: control group (group C), S1PR1 antagonist (FTY720) group (group F), remifentanil group (group R), remifentanil + S1PR1 antagonist (FTY720) group (group R+ F), remifentanil + incisional pain group (group R+ I), and remifentanil + incisional pain + S1PR1 antagonist (FTY720) group (group R+ I+ F). In C group, normal saline 0.1 μg·kg -1·min -1 was intravenously infused for 60 min. In R group, remifentanil 1.0 μg· kg -1·min -1 was infused for 60 min through the caudal vein. In F group, FTY720 3 nmol was intrathecally injected, and 10 min later normal saline 1.0 μg· kg -1·min -1 was infused for 60 min via the caudal vein. In R+ F group, FTY720 3 nmol was intrathecally injected, and 10 min later remifentanil 1.0 μg· kg -1·min -1 was infused for 60 min through the caudal vein. In R+ I group, remifentanil 1.0 μg·kg -1·min -1 was infused for 60 min through the caudal vein while the model of incisional pain was developed. In R+ I+ F group, FTY720 3 nmol was intrathecally injected, 10 min later the incisional pain model was prepared, and remifentanil 1.0 μg·kg -1·min -1 was injected for 60 min through the caudal vein at the same time. The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 24 h before remifentanil or normal saline infusion (T 0) and 2, 6, 24 and 48 h after stopping remifentanil or normal saline infusion (T 1-4). Rats were sacrificed after the last measurement of pain threshold, and the L 4-6 segments of dorsal root ganglion were taken for determination of the expression of S1PR1, NOD-like receptor thermal protein domain-associated protein 3 (NLRP3), interleukin-1β (IL-1β) and glutamate transporter-1 (GLT-1) protein and mRNA (by Western blot and quantitative polymerase chain reaction). Results:Compared with C group, the MWT was significantly decreased and TWL was shortened at T 1-4, the expression of S1PR1, NLRP3 and IL-1β protein and mRNA in dorsal root ganglion was up-regulated, and the expression of GLT-1 protein and mRNA in dorsal root ganglion was down-regulated in R group ( P<0.05), and no significant change was found in the parameters mentioned above in group F ( P>0.05). Compared with R group, MWT was significantly decreased and TWL was shortened at T 1-4, the expression of S1PR1, NLRP3 and IL-1β protein and mRNA in dorsal root ganglion was up-regulated, and GLT-1 protein and mRNA expression in dorsal root ganglion was down-regulated in R+ I group, and MWT was significantly increased and TWL was prolonged at T 1-4, the expression of S1PR1, NLRP3 and IL-1β protein and mRNA in the dorsal root ganglion was down-regulated, and GLT-1 protein and mRNA expression in the dorsal root ganglion was up-regulated in R+ F group ( P<0.05). Compared with R+ I group, MWT was significantly increased and TWL was prolonged at T 1-4, the expression of S1PR1, NLRP3 and IL-1β protein and mRNA in the dorsal root ganglion was down-regulated, and the expression of GLT-1 protein and mRNA in the dorsal root ganglion was up-regulated in R+ I+ F group( P<0.05). Conclusions:The mechanism by which remifentanil induces hyperalgesia is associated with up-regulation of S1PR1 expression, activation of inflammatory factors, and down-regulation of GLT-1 expression in the rats with incisional pain.

Sphingolipid Mediators of Myocardial Pathology

Cardiomyopathy is the leading cause of mortality worldwide. While the causes of cardiomyopathy continue to be elucidated, current evidence suggests that aberrant bioactive lipid signaling plays a crucial role as a component of cardiac pathophysiology. Sphingolipids have been implicated in the pathophysiology of cardiovascular disease, as they regulate numerous cellular processes that occur in primary and secondary cardiomyopathies. Experimental evidence gathered over the last few decades from both in vitro and in vivo model systems indicates that inhibitors of sphingolipid synthesis attenuate a variety of cardiomyopathic symptoms. In this review, we focus on various cardiomyopathies in which sphingolipids have been implicated and the potential therapeutic benefits that could be gained by targeting sphingolipid metabolism.

Expression of LDB2 in lung cancer tissues and its correlation with S1PR1 / 临床检验杂志

Objective@#To investigate the expression of LIM domain binding 2 (LDB2) in lung cancer tissues and its correlation with sphingosine-1 phosphate receptor 1 (S1PR1). @*Methods@#Lung cancer tissues and the corresponding adjacent tissues from 52 patients in Nantong Tumor Hospital during April 2010 and May 2011 were collected as the experimental group and the control group, respectively. The expression levels of LDB2 and S1PR1 were detected by the real-time PCR (qRT-PCR). The expression results of LDB2 gene were further verified by the Oncomine database, and its correlations with clinicopathological parameters were analyzed. The ROC curve was drawn to evaluate the diagnosis value of LDB2 expression in lung cancer. The correlation of LDB2 expression with the prognosis of lung cancer was analyzed by the “Kaplan-Meier Plotter” database. In addition, the relationship between LDB2 and S1PR1 was also analyzed. @*Results@#The expression levels of LDB2 in lung cancer tissues (0.158 [0.062,0.383]) were significantly lower than that in the adjacent tissues (0.403 [0.261,0.711], U=700.0, P＜ 0.01). A total of 9 eligible studies were retrieved from the Oncomine database, and their expressions of LDB2 were also low (P＜0.01). The expressions of LDB2 in lung cancer tissues were not related to gender, age, smoking history, pathological type, tumor size, TNM staging and lymphatic metastasis (P＞0.05). The results of ROC curve showed that when the area under the ROC curve (AUC ROC ) was 0.741 (95% CI:0.643-0.839) and the cut-off value was 0.247, the sensitivity and specificity of LDB2 in the diagnosis of lung cancer were 80.8% and 61.5%, respectively. The Kaplan-Meier survival analysis showed that the 5-year overall survival time of the patients with low expression of LDB2 was shorter than that of the patients with high expression of LDB2(P＜0.01). In addition, the expression levels of S1PR1 in lung cancer tissues (0.710[0.337,1.523]) were significantly lower than that in the adjacent tissues (1.582[0.913,3.533],U=780.0, P＜0.01), and the expression levels of S1PR1 in lung cancer tissues were positively correlated with that of LDB2(r=0.827,P＜0.01). @*Conclusion@#The expressions of LDB2 and S1PR1 in lung cancer tissues are down-regulated, and have a positive correlation, and they may play an important role in the occurrence and development of lung cancer.

Effects of fingolimod on sphingosine-1-phosphate signal in osteoclasts / 中华创伤骨科杂志

Objective To study the effects of fingolimod (FTY720) on the sphingosine-1-phosphate (S1P) signaling pathway in osteoclasts.Methods Murine RAW 264.7 macrophages were induced into osteoclasts by dexamethasone and 1 α,25-(OH)2VitD3 and identified by tartrate resistant acid phosphatase Trp staining.After the osteoclasts were divided into 2 groups,the experimental group was treated with 400 ng/mL FTY720-P while the control group was not.The signal expression of extracellular signal-regulated kinase 1 (ERK1),caspase9 and protein kinase(PKC) in the downstream of S1 P pathway was detected at the gene and protein levels,and the expression of bone morphogenetic protein-2(BMP-2) and transforming growth factor-β1 (TGF-β1),which are closely related to bone reconstruction,was detected.Results The RAW264.7 cells were successfully induced into osteoclasts identified by trataric acid phosphatase staining kit (TRAP).The expression of S1PR1 in osteoclasts was higher than that in other S1PRs.After culture for 48 hours,the expression of PKC mRNA in the experimental group was significantly lower than that in the control group while the expression of BMP-2 mRNA and TGF-[β1 mRNA was significantly increased in the experimental group than in the control group (P ＜ 0.05).However,there were no significant differences in expression of ERK1 mRNA or caspase9 mRNA between the 2 groups(P ＞ 0.05).Conclusions FTY720-P can affect the expression of PKC signal in the downstream of osteoclasts by affecting S1P signaling pathway,mainly by binding to S1PR1 signal pathway,and can also promote the expression of TGF-[β1 and BMP-2 in osteoclasts,ultimately affecting the function of osteoclasts.

Expression of S1PRl,S1PR4 in triple negative breast carcinoma and its significance / 临床与实验病理学杂志

Purpose To investigate the expression of sphingosine-1 phosphate receptor 1 (S1PR1) and sphingosine-1 phosphate receptor 4 (SIPR4) in triple negative breast carcinoma (TNBC) and to evaluate its correlation with the clinicopathologic features of TNBC. Methods 72 cases of tissue slides of TNBC were stained immunohistochemically and analyzed with image processing to calculate the S1PR1 and S1PR4 expression. Correlations of the S1PR1 and S1PR4 expression with the clinicopathologic features of TNBC were studied. Results Ki-67 index of high, moderate and low expression of the S1PR1 in TNBC were 48.89％, 36.11％ and 26.48％, respectively. The difference among them was significance (P＜0.001). Ki-67 index of high, moderate and low expression of the S1PR4 in TNBC were42.83％, 31.43％ and 28.93％, respectively. The difference among them was significance (P = 0.007 ). The positive rate of lymph node of high, moderate and low expression of the SI PR1 in TNBC were 31.4％, 48.6％ and 20.0％, respectively. The difference among them was significance (P = 0.012). The positive rate of lymph node of high, moderate and low expression of the S1PR4 in TNBC were 54.3％, 40.0％ and 5.7％, respectively. The difference among them was significance (P=0.010). The CD68 positive rate of high, moderate and low expression of the S1PR1 in TNBC were 47.22％, 42.59％ and31.48％, respectively. The difference among them was significance (P = 0.036). Both the difference of survive rate among high, moderate and low expression of the S1PR1 and S1PR4 were not significance (P = 0.209 and P =0.593 ). Conclusion High expression of S1PR1 and S1PR4 may contribute to the cellular proliferation and lymph node metastases in TNBC. The survive rate of TNBC maybe not related with both the S1PR1 and S1PR4 expression.

S1PR3 agonist RY-15 promotes bacterial clearance / 中华急诊医学杂志

Objective RY-15, a specific agonist of Sphingosine 1-phosphate Receptor 3, was synthesized for investigating the function and mechanism of S1PR3 in bacterial clearance. Methods Measure the ability of RY-15 with FITC to enter the THP-1 cell after coculture for 5 min, 10 min, 20 min, 30 min through confocal microscopy. The function of GY-5 and RY-15 in bacterial clearance was observed by gentamicin protection test. The phosphorylation level of ERK and p-ERK in THP-1 cell was detected by Western Blot after GY-5 and RY-15 stimulation for different times. Results According to confocal microscopy, RY-15 started to enter the THP-1 cell after stimulating for 10 min and the effect of entering cell was very obvious after stimulating for 30 min. Compared to GY-5 group, live bacteria in the macrophage were largely decreased in the RY-15 group( P<0.05). Conmpared to GY-5 group, the p-ERK level raised largely at different poins. Conclusions RY-15, a specific agonist of Sphingosine 1-phosphate Receptor 3, can promote bacterial clearance through entering cell and the phosphorylation level of ERK is a possible mechanism.

Lentiviral vectors carrying siRNA inhibit S1PR3 gene expression in the corpus cavernosum smooth muscle cells of rats with spontaneous hypertension / 中华男科学杂志

Objective@#To screen lentiviral vectors carrying siRNA which can specifically down-regulate the gene expression of the sphingosine-1-phosphate receptor 3 (S1PR3) in the corpus cavernosum smooth muscle (CCSM) cells of rats with spontaneous hypertension (SHT) and investigate the influence of the vectors on the signaling pathways of ROCK1, ROCK2 and eNOS in the CCSM cells of SHT rats.@*METHODS@#Using the S1PR3 mRNA sequence of the rat as an interfering target, we designed and synthesized three pairs of siRNA sequences (siRNA1, 2 and 3) targeting S1PR3 and one pair of negative control, and then constructed and packaged them into lentiviral vectors. We cultured the CCSM cells of SHT and Wistar-Kyoto (WKY) rats in vitro and randomly divided them into groups A (SHT untransfected control), B (SHT transfected and carrying negative control virus), C (SHT transfected and carrying siRNA1 targeting S1PR3), D (SHT transfected and carrying siRNA2 targeting S1PR3), E (SHT transfected and carrying siRNA3 targeting S1PR3), and F (WKY untransfected control). With the multiplicity of infection (MOI) = 60, we transfected the CCSM cells of the SHT rats with the lentiviral vector and then determined the expression of the green fluorescent protein (GFP) as well as the mRNA and protein expressions of S1PR3, ROCK1, ROCK2 and eNOS in the CCSM cells of the SHT and WKY rats by RT-PCR and Western blot.@*RESULTS@#Gene sequencing proved the successful construction of the lentiviral vector. The transfection efficiency of the CCSM cells of the rats was >80% in groups B, C, D and E. Compared with group A, the mRNA and protein expressions of S1PR3, ROCK1 and ROCK2 exhibited no significant difference in group B but were remarkably decreased in groups C, D, E and F (P0.05) but remarkably lower than those in group F (P0.05) but markedly increased in groups A, B, C and D (P< 0.05), while those of eNOS remarkably decreased in groups A, B, C, D and E (P< 0.05).@*CONCLUSIONS@#The three constructed lentiviral vectors carrying siRNA targeting different loci of the S1PR3 gene could significantly inhibit the expression of S1P3 as well as RhoA/Rho kinase signaling pathways in the CCSM cells of SHT rats, and the vector carrying siRNA3 exhibited the highest inhibitory effect.

Screening of lentiviral vectors carrying effective siRNA targeting S1P2 gene / 中国病理生理杂志

AIM: To screen the lentiviral vector carrying siRNA with higher efficiency of suppressing the sphingosine-1-phosphate receptor 2 (S1P2) gene expression in the primarily cultured corpus cavernosum smooth muscle cells of spontaneously hypertensive rats (SHR).METHODS: SHR and SD rats (n=5 each) were used for primarily culturing corpus cavernosum smooth muscle cells.The cells were randomly divided into 6 groups: SHR siRNA-1, SHR siRNA-2, SHR siRNA-3, SHR GFP, SHR control (SHR non-transfection group), and SD control (SD rat control group).Each group had 5 samples with 1.0×105 cells of each sample.At 72 h after transfection (MOI=60) with lentiviral vectors carrying S1P2 siRNA into the SHR corpus cavernosum smooth muscle cells, the expression of GFP was observed under fluorescence microscope.The protein expression of S1P2, ROCK1, ROCK2 and eNOS in the corpus cavernosum smooth muscle cells, and the mRNA expression of S1P2, ROCK1 and ROCK2 were determined by by Western blot and RT-PCR.RESULTS: The transfection efficiency of the corpus cavernosum smooth muscle cells in SHR siRNA-1, SHR siRNA-2, SHR siRNA-3 and SHR GFP groups were>80%.Compared with SHR control group, the mRNA levels and the protein expression of S1P2, ROCK1 and ROCK2 in SHR GFP group showed no remarkable changes, while those in SHR siRNA-1, SHR siRNA-2, SHR siRNA-3 and SD control groups were significantly lower than those in SHR control group (P<0.05).The protein expression of eNOS in SHR siRNA-1, SHR siRNA-2, SHR siRNA-3 and SHR GFP groups were not significantly changed as compared with SHR control group, but that in SD control group was significantly higher than that in SHR control group.CONCLUSION: Three groups of siRNA lentiviral vectors targeting S1P2 inhibit the expression of S1P2 in the corpus cavernosum smooth muscle cells of SHR, and by silencing the S1P2 expression, the expression of ROCK1 and ROCK2 is inhibited.Among them, siRNA-1 has the highest inhibitory efficiency.

Effects of sphingosine-1-phosphate receptor 1 alteration on proliferation of neural stem cells in hippocampus after traumatic brain injury / 中华创伤杂志

Objective To investigate the effects of sphingosine-1-phosphate receptor 1 (S1PR1) changes on the proliferation of endogenous neural stem cells (NSCs) in hippocampus after traumatic brain injury (TBI).Methods Rat TBI models were constructed by the means of controlled cortical injury.A total of 72 rats were included and randomly divided into four groups:sham,TBI,TBI + SEW (TBI + S1PR1 agonist SEW2871 intervention) and TBI + VPC group (TBI + S1PR1 antagonist VPC23019 intervention),with 18 rats per group.The TBI model was induced by a control cortical injury device.The injured rats in TBI + SEW group and TBI + VPC group were respectively administrated with S1PR1 agonist SEW2871 and antagonist VPC23019 at scheduled time points after TBI.Hippocampal S1PR1 expression was detected by Western-blotting and the proliferation of NSCs was assessed by double-labeled immunofluorescence staining at days 7,14 and 21 after injury.Results At days 7,14 and 21 after TBI,the hippocampal S1PR1 levels and NSCs proliferation amounts in sham,TBI,TBI + SEW and TBI + VPC groups were evidently different (P ＜ 0.05).In particular,the outstanding changes among the four groups above occurred at 7 d after injury were as following:S1PR1 expression in TBI group significantly increased by 1.56 times compared with that in sham group,and it was respectively upregulated by 66.67％ in TBI + SEW group and down-regulated by 20.29％ in TBI + VPC group (P ＜0.05).The nmmber of NSCs proliferation in TBI group was 2.08 times more than that in sham group,and it increased by 36.75％ in TBI + SEW group and reduced by 18.77％ in TBI + VPC group (P ＜ 0.05).Conclusion The expression of S1 PRI is closely associated with the proliferation of NSCs in hippocampus after TBI,indicating that S1PR1 activation may be an effective strategy to improve the posttraumatic neurogenesis.

Effects of sphingosine-1-phosphate receptor 1 alteration on proliferation of neural stem cells in hippocampus after traumatic brain injury / 中华创伤杂志

Objective To investigate the effects of sphingosine-1-phosphate receptor 1 (S1PR1) changes on the proliferation of endogenous neural stem cells (NSCs) in hippocampus after traumatic brain injury (TBI).Methods Rat TBI models were constructed by the means of controlled cortical injury.A total of 72 rats were included and randomly divided into four groups:sham,TBI,TBI + SEW (TBI + S1PR1 agonist SEW2871 intervention) and TBI + VPC group (TBI + S1PR1 antagonist VPC23019 intervention),with 18 rats per group.The TBI model was induced by a control cortical injury device.The injured rats in TBI + SEW group and TBI + VPC group were respectively administrated with S1PR1 agonist SEW2871 and antagonist VPC23019 at scheduled time points after TBI.Hippocampal S1PR1 expression was detected by Western-blotting and the proliferation of NSCs was assessed by double-labeled immunofluorescence staining at days 7,14 and 21 after injury.Results At days 7,14 and 21 after TBI,the hippocampal S1PR1 levels and NSCs proliferation amounts in sham,TBI,TBI + SEW and TBI + VPC groups were evidently different (P ＜ 0.05).In particular,the outstanding changes among the four groups above occurred at 7 d after injury were as following:S1PR1 expression in TBI group significantly increased by 1.56 times compared with that in sham group,and it was respectively upregulated by 66.67％ in TBI + SEW group and down-regulated by 20.29％ in TBI + VPC group (P ＜0.05).The nmmber of NSCs proliferation in TBI group was 2.08 times more than that in sham group,and it increased by 36.75％ in TBI + SEW group and reduced by 18.77％ in TBI + VPC group (P ＜ 0.05).Conclusion The expression of S1 PRI is closely associated with the proliferation of NSCs in hippocampus after TBI,indicating that S1PR1 activation may be an effective strategy to improve the posttraumatic neurogenesis.

Sphingosine-1-phosphate/sphingosine-1-phosphate receptor 1 and T cell migration / 药学学报

Lipid second messenger sphingosine-1-phosphate (S1P) can activate sphingosine-1-phosphate receptors (S1PRs) and participate in many biological processes, such as central nervous system homeostasis, cytokine production and T cell migration. S1PR1 is the main S1PR expressed on T cell surface. The interaction between S1P and S1PR1 plays a core role in T cell migration, which is important for T cell maturation, homing and activation. The central function of S1P/S1PR1 in T cell migration made it a popular drug target in treatment research of immune diseases. This review summarizes the current knowledge of the mechanism of S1P/S1PR1 mediating T cell migration and the research progress of S1P/S1PR1 as drug target.

Identification and application of sphingosine-1-phosphate receptor of human umbilical vein endothelial cells / 天津医药

Objective To identify the expression of sphingosine-1-phosphate receptor (S1PR) subtypes, C-myc and His tag proteins of human umbilical vein endothelial fusion cell line, EA.hy926 and human umbilical vein endothelial cells (HUVEC), CRL-1730 for studying the function of apolipoprotein M (ApoM)-S1P axis. Methods Two kinds of cells (EA. hy926 and CRL-1730) were cultured to reach the density of 60%-70% in vitro. Immunofluorescence technique was em?ployed to investigate the expressions of coagulation factorⅧ(FⅧ), ApoM, S1PR1-S1PR5, C-myc and His tag proteins. Re?sults (1) Two kinds of cells both expressed FⅧand ApoM. FⅧpresented scattered particle distribution in CRL-1730, while uniform distribution in EA.hy926. However, ApoM was strongly expressed and widely distributed in cytoplasm of two kinds of cells. (2) S1PR1-3 can be detected on their membrane other than S1PR4 and S1PR5. S1PR1 was highly expressed but S1PR2 and S1PR3 were in a low level expression. (3) Two kinds of cells both expressed C-myc and His tag proteins in cytoplasm. Conclusion Two kinds of cells have the properties of endothelial cells and can express FⅧ, ApoM, C-myc and His tag proteins. It is not suitable for choosing C-myc and/or His tag–conjugated recombinant ApoM to study the fuction of ApoM-S1P axis with these two kinds of cells.

S1PR3 agonist KRX-725 promotes bacterial clearance and affects the outcome of sepsis / 中华急诊医学杂志

Objective To study the role of KRX-725,a specific agonist of Sphingosin-1 phosphate receptor 3,S1PR3),in the function and mechanism of S1PR3 in respect of bacterial clearance.Methods Twenty healthy male C57BL/6 mice were randomly (random number) divided into two groups:KRX-725 group and control group.Septic mice model were established by intraperitoneal injection of E.coli (3 × 106),then KRX-725 (10 mg/kg) or the vehicle was administered intratracheally.Forty-eight-hour survival rate (n =12),bacterial colony numbers in peritoneal cavity and blood (n =5),and lung injury (n =3)were compared between two groups.In vitro,the peritoneal macrophages were stimulated by E.coli (cell∶E.coli=1∶10) with KRX-725 or the vehicle treatment.The reactive oxygen species (ROS) levels were detected by CM-H2DCFDA in macrophages.The bacteria clearance function of KRX-725 was observed by gentamicin protection test.Survival rates were analyzed with the Log-rank test.A 2-tailed student's t test was used to compare difference between two independent groups.Results Compared with the control group,the 48-hour survival rate of KRX-725 group was significantly higher (P ＜ 0.05).Bacterialload in the blood and the peritoneal lavage fluid (PLF) was greatly decreased in the KRX-725 group (blood:t =3.17,P ＜0.05;PLF:t =4.07,P ＜0.01).The lung tissues injury was also obviously reduced in the KRX-725 group of 24 hours after the injection of E.coli (lung injury score:KRX-725 group 1.4 ± 0.25;control group 2.4 ± 0.25) (t =2.89,P ＜ 0.05).In vitro,KRX-725 could up-regulate the ROS levels in macrophage at 20 min and 30 min after E.coli injected intra-peritoneally (20 min fluorescent intensity:KRX-725 group 522.9 ± 38.76,control group 385.9 ± 15.90,P ＜ 0.05;30 min fluorescent intensity:KRX-725 group 519.7 ±25.02,control group 384.5 ± 15.28,P ＜0.01).The bacterial load in the KRX-725 treated macrophage were significantly decreased at 3 h and 6 h after E.coli injected intra-peritoneally (3 h:KRX-725 group 286.5 ±98.35,control group 710.8 ± 107.8,P ＜0.05;6 h:KRX-725 group 72.5 ±6.45,control group 205.8 ±66.76,P ＜0.01).Conclusion In vivo,KRX-725 could improve the survival rate of septic mice,decrease the bacterial lioad in the blood and PLF,and reduce the lung injury.In vitro,KRX-725 could up-regulate the ROS level in macrophages and accelerate the bacterial clearance.

Sphingosine-1-phosphate receptor-2 attenuates lipopolysaccharide-induced acute lung injury / 中国病理生理杂志

AIM:To investigate the effects and mechanisms of sphingosine-1-phosphate receptor-2 (S1P2R) on lipopolysaccharide (LPS)-induced acute lung injury (ALI).METHODS:ALI model was induced by intratracheal ad-ministration of LPS in both wild-type mice and S1P2R-deficient mice.The pathological changes in the lung tissues were ob-served, and the protein concentration , total cell number, neutrophil ratio, TNF-αlevel and IL-6 level were determined in the bronchoalveolar lavage fluid (BALF) 24 h after LPS injection.In order to investigate the mechanisms of S1P2R in LPS-induced ALI, 10 min before LPS injection, both wild-type mice and S1P2R-deficient mice were injected with nitric oxide synthase inhibitor by tail vein injection , the pathological changes of the lung tissues were observed , and the protein concen-tration and total cell number in BALF were determined 12 h after LPS injection .RESULTS: Compared with wild-type mice, S1P2R-deficient mice showed more severe LPS-induced ALI, and the protein concentration , neutrophils and inflam-matory cytokines in BALF were significantly increased in S1P2R-deficient mice.Administration of nitric oxide synthase in-hibitor Nω-L-nitro-arginine methyl ester protected S1P2R-deficient mice from aggravation of ALI .CONCLUSION:S1P2R mediates the protection from LPS-induced ALI possibly through inhibiting nitric oxide synthase .

Role of sphingosine-1-phosphate receptor 1 in pain modulation / 中国药理学通报

Sphingosine-1-phosphate receptor 1(S1PR1) is a new member of G protein-coupled receptor family. A great body of data suggest S1PR1 is capable of regulating lots of downstream signaling molecules and cellular processes. It is found that S1P/S1PR1 plays an important role in the development and mainte-nance of pain. However, it is controversial whether activation of S1PR1 would enhance or attenuate pain. Here, recent studies ＜br> and current perspectives are discussed in order to better under-stand the biological and pathological roles of S1PR1 in pain mod-ulation.

Effect of sphingosine-1-phosphate receptor 2 on coronary endothelial cells proliferation / 实用医学杂志

Objective To explore the role of sphingosine-1-phosphate receptor (S1PR2) in human coronary artery endothelial cell proliferation in vitro. Methods MTT assay was used to detect cell proliferation in human coronary artery endothelial after treatment of S1P and S1PR2 antagonist JTE-013. Phosphor-ERK and total- ERK level were measured by western blot in endothelial after treatment of S1P and JTE-013. Results 1 μmol/L S1P significantly increased endothelial cells proliferation. S1PR2 antagonist JTE-013 inhibited S1P-induced endothelial cell proliferation in dose-dependent manner. S1PR2 antagonist JTE-013 significantly inhibited S1P-induced phosphor-ERK level in endothelial cells. Conclusion S1PR2 may involve in S1P-induced endothelial cell proliferation through activation of ERK pathway.

FTY720: Mechanism of Action and Potential Benefit in Organ Transplantation

FTY720 is a novel immunomodulator that has proven effective in animal models of transplantation and autoimmunity, has achieved promising results in Phase I and Phase II studies of renal transplantation in humans, and is currently undergoing phase III studies. FTY720 acts as a high-affinity agonist at the sphingosine 1-phosphate receptor-1 (S1P1), where it internalises the receptor and causes alterations to the normal circulation of lymphocytes between the blood and lymphoid tissue. Unlike conventional immunosuppressants, FTY720 does not impair the activation, proliferation or effector functions of T- and B-cells. Further development of FTY720 is in progress, including trials in autoimmune disorders as well as transplantation. This review summarises the mechanism of action of FTY720, its effects in models of transplantation and autoimmunity, and results from clinical trials in humans.