Apoptosis ; Ceramides ; biosynthesis ; Sphingomyelins ; metabolism

Autosomal recessive congenital ichthyosis (ARCI) is characterized by being born as collodion babies, hyperkeratosis, and skin scaling. We described a collodion baby at birth with mild ectropion, eclabium, and syndactyly. Whole exome sequencing showed a compound heterozygous variant c.[56C>A], p.(Ser19X) and c.[100G>A], p.(Ala34Thr) in the PNPLA1 gene [NM_001145717; exon 1]. The protein encoded by PNPLA1 acts as a unique transacylase that specifically transfers linoleic acid from triglyceride to ω-hydroxy fatty acid in ceramide, thus giving rise to ω-O-acylceramide, a particular class of sphingolipids that is essential for skin barrier function. The variant was located in the patatin core domain of PNPLA1 and resulted in a truncated protein which could disrupt the function of the protein. This case report highlights a novel compound heterozygous mutation in PNPLA1 identified in a Chinese child.
Humans ; Infant, Newborn ; Acyltransferases/genetics* ; Ceramides/metabolism* ; Collodion ; Ichthyosis, Lamellar/genetics* ; Lipase/metabolism* ; Mutation ; Phospholipases/genetics*

Sphingolipids, especially ceramide and S1P, are structural components of biological membranes and bioactive molecules which participate in diverse cellular activities such as cell division, differentiation, gene expression and apoptosis. Emerging evidence demonstrates the role of sphingolipids in hepatocellular death, which contributes to the progression of several liver diseases including ischaemia-reperfusion liver injury, steatohepatitis or hepatocarcinogenesis. Furthermore, some data indicate that the accumulation of some sphingolipids contributes to the hepatic dysfunctions. Hence, understanding of sphingolipid may open up a novel therapeutic avenue to liver diseases. This review focuses on the progress in the sphingolipid metabolic pathway with a focus on hepatic diseases and drugs targeting the sphingolipid pathway.
Apoptosis ; Ceramides ; metabolism ; Fatty Liver ; metabolism ; physiopathology ; Humans ; Liver Diseases ; metabolism ; physiopathology ; Lysophospholipids ; metabolism ; Reperfusion Injury ; metabolism ; physiopathology ; Sphingolipids ; metabolism ; Sphingosine ; analogs & derivatives ; 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

Ceramides play major roles in maintaining the epidermal barrier. It has been sus-pected that the depletion of ceramides, associated with disrupted barrier function in the epidermis, leads to the clinical manifestation of dryness and inflammation seen in patients with psoriasis. The aim of the present study was to determine the relation-ship between the level of ceramide synthesis in the epidermis and the clinical severity in patients with psoriasis. Samples from lesional and unlesional epidermis obtained from psoriasis patients were incubated with [14C]serine, an initiator of ceramide syn-thesis. otal ceramide was fractionated using high performance thin layer chromato-graphy, and the radioactivity was measured. The clinical severity of psoriasis was graded according to the psoriasis area and severity index scoring system. The level of ceramide synthesis in the lesional epidermis of patients was significantly lower than that in the unlesional epidermis and bore a negative correlation with the clinical severity of psoriasis. The present results suggest that the decreased level of ceramide synthesis in the epidermis contributes to the clinical severity of psoriasis.
Adolescent ; Adult ; Biological Markers ; Ceramides/*metabolism ; Fatty Acids/*metabolism ; Female ; Humans ; Korea/epidemiology ; Male ; Psoriasis/classification/epidemiology/*metabolism/*pathology ; Severity of Illness Index ; Skin/*metabolism/*pathology ; Statistics

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

PURPOSE: Effect of recombinant human growth hormone (rhGH) administration on lipid storage, and its subsequent effect on insulin sensitivity have not yet been adequately examined. Thus, we investigated the effects of rhGH treatment on muscle triglyceride (TG) and ceramide content, and insulin sensitivity after 4 weeks of rhGH administration in rats. MATERIALS AND METHODS: Fourteen rats were randomly assigned to two groups: rhGH injection group (GH, n = 7) and saline injection group (CON, n = 7). GH received rhGH by subcutaneous injections (130microgram/kg(-1)/day(-1), 6 days/week(-1)) for 4 weeks, while CON received saline injections that were equivalent in volume to GH group. Intramuscular TG and ceramide content and hepatic TG content were measured. To determine insulin sesitivity, oral glucose tolerance test (OGTT) and muscle incubation for glucose transport rate were performed in rats, and used as indicators of insulin sensitivity. We also examined plasm lipid profiles. RESULTS: After 4 weeks of rhGH treatment, the GH group had higher muscle and liver TG contents than the CON (p < 0.05). Ceramide content in GH was significantly greater than that in CON (p < 0.05). GH also had higher plasma levels of FFA (p < 0.05), glucose and insulin responses during OGTT (p < 0.05), and lower glucose transport rates in submaximal insulin concentration (p < 0.05) as compared with CON. Results indicate that rhGH treatment is associated with insulin resistance in rats. CONCLUSION: rhGH treatment elevated muscle TG and ceramide content, and hepatic TG content. Thus, elevation of these compounde by rhGH treatment could contribute to the development of insulin resistance in rats.
Animals ; Ceramides/metabolism ; Glucose/metabolism ; Glucose Transporter Type 4/metabolism ; Human Growth Hormone/*administration & dosage ; Humans ; *Insulin Resistance ; Male ; Muscle, Skeletal/*drug effects/*metabolism ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins/administration & dosage ; Triglycerides/metabolism

OBJECTIVETo investigate the expression of ceramide produced by sphingomyelin in normal laryngeal mucosa, laryngeal precancerous lesion and laryngeal carcinoma.

METHODSOne hundred and seventy-eight consecutive patients with leukoplakia larynx were identified from the archived pathology files of Eye Ear Nose and Throat Hospital of Fudan University from 1991 to 2001. Among them, 31 patients developed laryngeal carcinoma. Flow cytometry (FCM) and immunohistochemistry were performed to test DNA content and ceramide expression on normal tissue, precancerous lesions and laryngeal carcinoma

RESULTSAmong thirty-one patients with laryngeal carcinoma, thirty-one cases are all aneuploids, diploids in all normal laryngeal mucosa and three diploids, twenty-eight aneuploids in precancerous lesions. Expression of ceramide decreased gradually from normal tissue, precancerous lesions to laryngeal carcinoma Cell staining per high-power field: (400 +/- 30, 180 +/- 20, 10 +/- 10), t test: P < 0.01. The expression of ceramide in DNA diploid cell (400 +/- 20) is more than that in aneuploid cell (150 +/- 10), t test: P < 0.01.

CONCLUSIONSCeramide, the second messenger in apoptosis, plays a significant role from precancerous lesion to carcinoma of larynx. Reduction of ceramide may be the key factor contribution to laryngeal carcinogenesis.

Aged ; Aged, 80 and over ; Apoptosis ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Transformation, Neoplastic ; pathology ; Ceramides ; metabolism ; Female ; Humans ; Laryngeal Neoplasms ; metabolism ; pathology ; Larynx ; metabolism ; pathology ; Male ; Middle Aged ; Precancerous Conditions ; metabolism ; pathology

Ceramides are the main lipids in the stratum corneum and are generated during cellular stress and apoptosis by de novo synthesis or by the action of sphingomyelinase. In addition, they are lipid second messengers produced by sphingolipid metabolism and trigger important cell responses, including protein kinase C-alpha (PKC-alpha) activation and the stimulation of signal transduction pathways with apoptosis and stress-activated protein kinases (SAPK), such as c-jun N-terminal kinase (JNK). Thus, ceramides have anti-proliferative and apoptotic effects. This study measured the changes in the levels of epidermal ceramides and ceramide-related apoptotic signaling molecules in psoriasis patients. Samples from lesional and non-lesional epidermis were obtained from psoriasis patients. Total ceramides were fractionated using thin-layer chromatography, and the levels of PKC-alpha and JNK expression were measured using Western blot analysis with specific antibodies. The ceramide level was reduced significantly, and this was associated with the downregulation of apoptotic signaling molecules, such as PKC-alpha and JNK, in the lesional epidermis of psoriasis patients. These results suggest that the decreased level of ceramides downregulates the apoptotic pathway, leading to epidermal proliferation in psoriasis.
Adult ; Apoptosis/physiology ; Blotting, Western ; Ceramides/*metabolism ; Chromatography, Thin Layer ; Epidermis/metabolism/pathology/physiopathology ; Female ; Humans ; JNK Mitogen-Activated Protein Kinases/metabolism ; Male ; Protein Kinase C-alpha/metabolism ; Psoriasis/metabolism/*pathology/physiopathology ; Severity of Illness Index ; Signal Transduction/*physiology

OBJECTIVETo investigate the relationship among a 50-Hz MF-induced epidermal growth factor receptor (EGFR) clustering, acid sphingomyelinase (A-SMase) and ceramide (CER), and to explore the possible mechanism of receptor clustering.

METHODSHuman amnion (FL) cells were exposed to a 50-Hz sinusoidal magnetic field at 0.4 mT for 15 min with or without imipramine, a specific inhibitor of A-SMase and ceramide pretreatment. EGF treatment served as the positive control and DMSO treatment served as the solvent control. The EGFR was labeled with polyclonal anti-EGFR antibody and the clustering of EGFR was analyzed using immunofluorescence and confocal microscopy. The percentage of cells with EGFR clustering was counted and compared.

RESULTSBoth EGF treatment and 50-Hz MF exposure could induce EGFR clustering. However, the effect could be eliminated by imipramine pretreatment for 4 hours. When FL cells were incubated with ceramide following the imipramine pretreatment for 30 min, EGFR clustering induced by 50-Hz MF exposure could be recovered.

CONCLUSIONEGFR clustering induced by 50-Hz MF depends on A-SMase activity, and ceramide, as the hydrolyzate from A-SMase might participate in the process of EGFR clustering.

Amnion ; cytology ; Cell Line ; Cell Membrane ; metabolism ; radiation effects ; Ceramides ; metabolism ; Epithelial Cells ; metabolism ; radiation effects ; Humans ; Magnetic Fields ; adverse effects ; Receptor, Epidermal Growth Factor ; metabolism ; Sphingomyelin Phosphodiesterase ; metabolism ; physiology