Animals ; Antioxidants ; pharmacology ; Apoptosis ; drug effects ; Atherosclerosis ; prevention & control ; Ceramides ; analysis ; Dietary Fats ; administration & dosage ; Emodin ; pharmacology ; Lipids ; blood ; Male ; Rabbits ; Signal Transduction ; Sphingomyelin Phosphodiesterase ; metabolism ; Sphingomyelins ; metabolism

OBJECTIVETo investigate the effects of Artesunate(Art) on the LX-2 cell.

METHODSThe cultured hepatic stellate cells were divided into control group and Art-treated groups with 250,350,450 µmol/L. The rate of cellular proliferation was detected by MIT assay, the content of ceramide (Cer)was determined by HPLC method, the content of hydroxyproline (Hyp) was determined by enzyme digestion method, the expressions of PPAR-γ, p53 and Caspase 3 were detected by Western blot.

RESULTSCompared with control group, IX-2 treated with Art were inhibited in a concentration-dependent manner(P < 0.01). Art could significantly increase the content of cerarnide in LX-2 ( P <0.01), and the content of Hyp was significantly decreased (P <0.05, P <0.01). The expressions of PPAR-γ, p53 and Caspase 3 were increased compared with that of control group(P < 0.01).

CONCLUSIONArtesunate could inhibit the proliferation and induce apoptosis of hepatic stellate cells through upregulating ceramide.

Apoptosis ; Artemisinins ; pharmacology ; Caspase 3 ; metabolism ; Cell Line ; Cell Proliferation ; Ceramides ; metabolism ; Hepatic Stellate Cells ; drug effects ; Humans ; Hydroxyproline ; metabolism ; Liver Cirrhosis ; PPAR gamma ; metabolism

OBJECTIVETo study the effect of DNR on HL-60 cells apoptosis in vitro and the related mechanism.

METHODSThe apoptosis of HL-60 was observed by microscope, flow cytometry (FCM) and DNA electrophoresis and various apoptosis-associated proteins expression by immunocytochemistry (IC) and FCM assays; the changes of apoptosis in HL-60 cells treated with DNR or suppressors PDTC or FB1 were also observed.

RESULTSWhen treated with 0.2 approximately 2.0 micro mol/L DNR, the percentage of apoptotic HL-60 cells increased with the dose increasing and the time extending, and the typical apoptotic cells and the appearance of apoptotic DNA ladder were observed. It was shown that after treatment with 1 micro mol/L DNR, the fluorescence intensity index (FI) of both bcl-2 and c-myc in HL-60 cells decreased, the FI of Bax, caspase-3 increased at 2 h, but decreased at 5 h, the FI of NF-kappaB increased. After adding PDTC, the apoptosis percentage of HL-60 cells decreased, but FB1 didn't present these effect.

CONCLUSIONIt suggested from the results that at certain concentration, DNR can induce the apoptosis of HL-60 cells in vitro. The mechanism was supposed by suppressing the expression of bcl-2 and c-myc and activating the expression of Bax and caspase-3, NF-kappaB and ROS had the marked correlation with the apoptosis process, but the ceramide synthase wasn't associated with it.

Apoptosis ; drug effects ; Caspase 3 ; Caspases ; analysis ; Ceramides ; biosynthesis ; Daunorubicin ; pharmacology ; Dose-Response Relationship, Drug ; HL-60 Cells ; Humans ; Immunohistochemistry ; NF-kappa B ; analysis ; Proline ; analogs & derivatives ; pharmacology ; Proto-Oncogene Proteins c-myc ; analysis ; Reactive Oxygen Species ; Thiocarbamates ; pharmacology

OBJECTIVETo observe the effects of antioxidation and ceramide content of improved prescription of Didang-tang (IPDT) on exprimental atherosclerosis(AS) rabbits.

METHODPlasm Superoxide Dismutase(SOD) activity was detected with micro-content fast detecting method, Plasm Malondialdehyde(MDA) content with improved BaMuGuoFu method, and Aortic Ceramide (CER) content with thinlayer scanning.

RESULTIPDT could effectivly improve plasma SOD activity and decrease plasma MDA content and decrease aortic CER content.

CONCLUSIONIPDT on exprimental AS is related to the improvement of antioxidation and decrease of CER content.

Animals ; Antioxidants ; pharmacology ; Arteriosclerosis ; metabolism ; Ceramides ; metabolism ; Cinnamomum ; chemistry ; Drug Combinations ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Female ; Leeches ; chemistry ; Male ; Materia Medica ; pharmacology ; Plants, Medicinal ; chemistry ; Rabbits ; Rheum ; chemistry

Because nerve growth factor (NGF) is elevated during inflammation, plays a causal role in the initiation of hyperalgesia, and is known to activate the sphingomyelin signalling pathway, we examined whether NGF and its putative second messenger, ceramide, could modulate the excitability of capsaicin-sensitive adult sensory neurons. Using the whole-cell patch-clamp recording technique, exposure of isolated sensory neurons to either 100 ng/mL NGF or 1 mmol/L N-acetyl sphingosine (C2-ceramide) produced a 3-4 fold increase in the number of action potentials (APs) evoked by a ramp of depolarizing current in a time-dependent manner. Intracellular perfusion with bacterial sphingomyelinase (SMase) also increased the number of APs suggesting that the release of native ceramide enhanced neuronal excitability. Glutathione, an inhibitor of neutral SMase, completely blocked the NGF-induced augmentation of AP firing, whereas dithiothreitol, an inhibitor of acidic SMase, was without effect. In the presence of glutathione and NGF, exogenous ceramide still enhanced the number of evoked APs, indicating that the sensitizing action of ceramide was downstream of NGF. To investigate the mechanisms of actions for NGF and ceramide, isolated membrane currents were examined. Both NGF and ceramide facilitated the peak amplitude of the TTX-resistant sodium current (TTX-R I(Na)) by approximately 1.5-fold and shifted the activation to more hyperpolarized voltages. In addition, NGF and ceramide suppressed an outward potassium current (I(K)) by ~35%. The inflammatory prostaglandin, PGE2, produced an additional suppression of I(K) after exposure to ceramide (~35%), suggesting that these agents might act on different targets. Based on the existing literature, it is not clear whether this NGF-induced sensitization is mediated by the high-affinity TrkA receptor or the low-affinity p75 neurotrophin receptor. Pretreatment with the p75 blocking antibody completely prevents the NGF-induced increase in the number of APs evoked by the current ramp. Although the sensitization by NGF was blocked, the antibody had no effect on the capacity of ceramide, a putative downstream signalling molecule, to enhance the excitability. Ceramide can be metabolized by ceramidase to sphingosine (Sph) and Sph to sphingosine 1-phosphate (S1P) by sphingosine kinase. It is well established that each of these products of sphingomyelin metabolism can act as intracellular signalling molecules. This raises the question as to whether the enhanced excitability produced by NGF was mediated directly by ceramide or required additional metabolism to Sph and/or S1P. Sph applied externally did not affect the neuronal excitability whereas internally perfused Sph augmented the number of APs evoked by the depolarizing ramp. Furthermore, internally perfused S1P enhanced the number of evoked APs. This sensitizing action of NGF, ceramide, and internally perfused Sph, were abolished by dimethylsphingosine (DMS), an inhibitor of sphingosine kinase. In contrast, internally perfused S1P enhanced the number of evoked APs in the presence of DMS. These observations support the idea that the metabolism of ceramide/Sph to S1P is critical for the sphingolipid-induced modulation of excitability. Thus, our findings indicate that the pro-inflammatory agent, NGF, can rapidly enhance the excitability of sensory neurons. This NGF-induced sensitization is mediated by activation of the sphingomyelin signalling pathway wherein intracellular S1P derived from ceramide, acts as an internal second messenger to regulate membrane excitability, however, the effector system whereby S1P modulates excitability remains undetermined.
Action Potentials ; Animals ; Cells, Cultured ; Ceramides ; pharmacology ; Lysophospholipids ; metabolism ; Nerve Growth Factor ; physiology ; Patch-Clamp Techniques ; Phosphotransferases (Alcohol Group Acceptor) ; metabolism ; Sensory Receptor Cells ; cytology ; Signal Transduction ; Sphingomyelins ; physiology ; Sphingosine ; analogs & derivatives ; metabolism

This study is to investigate the effect and mechanism of puerarin on DNA damage of HaCaT cells induced by UVB. Puerarin pre-treated cells were irradiated with UVB at 30 mJ x cm(-2). Twenty four hours after irradiation, DNA damage was detected by comet assay, ceramide was measured by thin layer chromatography and gas chromatography, intracellular free calcium ion was analyzed by flow cytometry, the phosphorylation level of p38 protein was examined by Western blotting method. Levels of DNA damage, ceramide, free calcium ion and p-p38 protein were elevated in UVB model cells. Contrary to the model group, all indicators above were reduced in all groups pre-treated by puerarin. Puerarin restrains the ceramide accumulation to block downstream p38 MAPK pathway and calcium ion rising, therefore reduces DNA damage in HaCaT cells induced by UVB.
Calcium ; metabolism ; Cell Line ; Ceramides ; metabolism ; DNA Damage ; drug effects ; radiation effects ; Down-Regulation ; Humans ; Isoflavones ; pharmacology ; Keratinocytes ; cytology ; metabolism ; Phosphorylation ; Signal Transduction ; drug effects ; Ultraviolet Rays ; adverse effects ; p38 Mitogen-Activated Protein Kinases ; metabolism

Sphingolipids as an important regulator play a critical role in the cell biological functions. Among them, ceramide (Cer) and sphingosine (Sph) induce apoptosis and inhibit cell proliferation; on the contrary sphingosine 1-phosphate (S1P) promotes cell survival and proliferation. The balance between ceramide/sphingosine and S1P forms a so-called "sphingolipid-rheostat", which decides the cell fate. Sphingosine kinases, which catalyze the phosphorylation of sphingosine to S1P, are critical regulators of this balance. Here, we review the role of sphingosine kinase 1 (SphK1) in regulating fundamental biological processes and tumorigenesis and the potential of SphK1 as a new target for cancer therapeutics.
Amino Alcohols ; pharmacology ; Animals ; Apoptosis ; drug effects ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Ceramides ; metabolism ; Enzyme Activation ; Enzyme Inhibitors ; pharmacology ; Humans ; Lysophospholipids ; metabolism ; Neoplasms ; metabolism ; pathology ; Neovascularization, Pathologic ; Phosphorylation ; Phosphotransferases (Alcohol Group Acceptor) ; antagonists & inhibitors ; metabolism ; Sphingosine ; analogs & derivatives ; metabolism ; Thiazoles ; pharmacology

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.
A549 Cells ; Acetic Acid ; Animals ; Anthozoa ; chemistry ; Anti-Ulcer Agents ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Biological Products ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Breast Neoplasms ; drug therapy ; Ceramides ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Disease Models, Animal ; Ethanol ; Female ; Humans ; Lung Neoplasms ; drug therapy ; MCF-7 Cells ; Magnetic Resonance Spectroscopy ; methods ; Rats ; Spectroscopy, Fourier Transform Infrared ; methods ; Steroids ; chemistry ; isolation & purification ; pharmacology ; therapeutic use ; Ulcer ; chemically induced ; drug therapy

Abstract Phospholipase D (PLD) plays an important role as an effector in a variety of physiological processes that reveal it to be a member of the signal transducing phospholipases. Recently, PLD2 was reported as a necessary intermediate in preventing apoptosis induced by hydrogen peroxide or hypoxia in rat pheochromocytoma (PC12) cells. The data presented here show that both PLD isozymes, PLD1 and PLD2 are also required in attenuating glutamate-induced cell death in PC12 cells. Treatment of PC12 cells with glutamate resulted in induction of apoptosis in these cells, which is accompanied by decreased PLD activity and increased ceramide concentration. Incubation of PC12 cells with exogenous C6-ceramide showed a time-dependent decrease of PLD activity. When cDNAs of PLD1 and PLD2 were transfected into PC12 cells respectively, overexpression of PLD1 or PLD2 resulted in inhibition of glutamate-induced apoptotic cell death. These data indicate that both PLD1 and PLD2 play a protective role against glutamate-induced cell death in PC12 cells.
Animals ; Apoptosis/drug effects/*physiology ; Cell Survival/drug effects ; Ceramides/pharmacology ; Dose-Response Relationship, Drug ; Enzyme Activation ; Gene Expression Regulation, Enzymologic/drug effects ; Glutamic Acid/*toxicity ; Isoenzymes/drug effects/genetics/*metabolism ; Kinetics ; PC12 Cells ; Phospholipase D/chemistry/drug effects/genetics/*metabolism ; Rats ; Sphingolipids/metabolism

TMSG-1 is a newly discovered tumor metastasis suppressor gene, which plays important roles in promoting apoptosis and inhibiting invasion and metastasis of tumor cells. The inhibitory function of TMSG-1 in tumor cells may be related to vacuolar H+-ATPase and ceramide, but the underlying mechanism remains unknown. Studies on TMSG-1 are limited worldwide, and only a research group in Shanghai and our group have recently studied on it. As a new research field, the function of TMSG-1 remains to be explored. This review discusses the discovery of TMSG-1, structure of its encoded protein, its roles and possible mechanism in inhibiting tumor invasion and metastasis.
Animals ; Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Ceramides ; chemical synthesis ; pharmacology ; Enzyme Activation ; Humans ; Membrane Proteins ; metabolism ; physiology ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Neoplasms ; metabolism ; pathology ; Phosphorylation ; Sphingosine N-Acyltransferase ; metabolism ; physiology ; Tumor Suppressor Proteins ; metabolism ; physiology ; Vacuolar Proton-Translocating ATPases ; metabolism