OBJECTIVESTo investigate the effects of antisense oligodeoxynucleotide(ASON) on the cyclic nucleotide monophosphates (cNMP) in smooth muscle cells of human corpus cavernosum, and provide experimental groundwork for the gene therapy of erectile dysfunction.

METHODSPDE5 gene ASON(containing exon 1) was transfected into the corpus cavernosum smooth muscle cells with the presence of liposome DOTAP. Another sense oligodeoxynucleotide(SON) and 1% of bovine serum were also transducted into the cells as controls. Two of cNMP, cAMP and cGMP, were probed and measured by ELISA at 1, 2, 4, 6, 10, 24 and 48 h after transfection.

RESULTSAfter transfection, the level of cGMP(1-6 h) in human corpus cavernosum smooth muscle cells was significantly higher than that in controls(P < 0.01).

CONCLUSIONSThe PDE5 gene ASON had been showed to manifest stimulative effect on the cGMP in smooth muscle cells of human corpus cavernosum in vitro, and it provides experimental groundwork for the gene therapy of erectile dysfunction.

3',5'-Cyclic-GMP Phosphodiesterases ; antagonists & inhibitors ; genetics ; Cyclic AMP ; metabolism ; Cyclic GMP ; metabolism ; Cyclic Nucleotide Phosphodiesterases, Type 5 ; Humans ; Male ; Muscle, Smooth ; drug effects ; metabolism ; Oligodeoxyribonucleotides, Antisense ; pharmacology ; Penis ; cytology

This study was designed to elucidate high-K+induced response of circular and longitudinal smooth muscle from human gastric corpus using isometric contraction. Contraction from circular and longitudinal muscle stripes of gastric corpus greater curvature and lesser curvature were compared. Circular smooth muscle from corpus greater curvature showed high K+ (50 mM)-induced tonic contraction. On the contrary, however, longitudinal smooth muscle strips showed high K+ (50 mM)-induced sustained relaxation. To find out the reason for the discrepancy we tested several relaxation mechanisms. Protein kinase blockers like KT5720, PKA inhibitor, and KT5823, PKG inhibitor, did not affect high K+-induced relaxation. K+ channel blockers like tetraethylammonium (TEA), apamin (APA), glibenclamide (Glib) and barium (Ba2+) also had no effect. However, N(G)-nitro-L-arginine (L-NNA) and 1H-(1,2,4) oxadiazolo (4,3-A) quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase (sGC) and 4-AP (4-aminopyridine), voltage-dependent K+ channel (KV) blocker, inhibited high K+-induced relaxation, hence reversing to tonic contraction. High K+-induced relaxation was observed in gastric corpus of human stomach, but only in the longitudinal muscles from greater curvature not lesser curvature. L-NNA, ODQ and KV channel blocker sensitive high K+-induced relaxation in longitudinal muscle of higher portion of corpus was also observed. These results suggest that longitudinal smooth muscle from greater curvature of gastric corpus produced high K+-induced relaxation which was activated by NO/sGC pathway and by KV channel dependent mechanism.
Apamin ; Barium ; Carbazoles ; Contracts ; Glyburide ; Guanylate Cyclase ; Humans ; Intracellular Signaling Peptides and Proteins ; Isometric Contraction ; Muscle, Smooth ; Muscles ; Protein Kinases ; Pyrroles ; Relaxation ; Stomach ; Tetraethylammonium

OBJECTIVETo observe the effects of PSD95 gene specific siRNAs on neuropathic pain relief, neuron viability, and postsynaptic calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) phosphorylation in vitro and in vivo.

METHODSGene-specific siRNAs of rat PSD95 were synthesized chemically for transfection. Adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: naïve group (n=6), sham group (n=6), and sciatic nerve chronic constriction injury (CCI) group (n=24). The CCI group was further divided into 4 groups (n=6 in each group), which were pretreated with normal saline, transfection vehicle, negative control siRNAs, and PSD95 gene specific siRNAs respectively. All the subgroups received corresponding agents intrathecally for 3 days, started one day before the CCI of sciatic nerve. Both mechanical allodynia and thermal hyperalgesia were measured on post-operative day 3 and 7. PSD95 gene silenced NG108-15 cells were further stimulated by glutamate, with the cell viability and the expression/phosphorylation of CaMKIIα measured by MTT cell proliferation assay and Western blot, respectively.

RESULTSThe siRNAs decreased PSD95 mRNA level significantly both in vivo and in vitro. Neuropathic pain rats pretreated with PSD95 gene specific siRNAs exhibited significant elevation in the mechanical withdrawal threshold and paw withdrawal thermal latency, without affecting the baseline nociception. PSD95 gene silencing enhanced neuronal tolerance against the glutamate excitotoxicity, meanwhile the phosphorylation of CaMKIIα Thr286 was attenuated.

CONCLUSIONPre-emptive administration of PSD95 gene specific siRNAs may attenuate the central sensitization CaMKIIα-related signaling cascades, leading to the relief of neuropathic pain.

Animals ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; metabolism ; Cells, Cultured ; Disks Large Homolog 4 Protein ; Intracellular Signaling Peptides and Proteins ; genetics ; Male ; Membrane Proteins ; genetics ; Neuralgia ; therapy ; Neurons ; physiology ; Phosphorylation ; RNA, Small Interfering ; genetics ; Rats ; Rats, Sprague-Dawley

Laryngeal squamous cell carcinoma (LSCC) is the most common type of head and neck squamous cell carcinoma (HNSCC) worldwide. Protein phosphatase 2A (PP2A) dysfunction has been widely reported in a broad range of malignancies due to its distinctive role in miscellaneous cellular processes. However, it is poorly understood whether aberrant alterations of PP2A are involved in the network of oncogenic events in LSCC. Here, we detected a panel of PP2A-associated proteins using western blot in both laryngeal squamous cell carcinoma tissues and paired adjacent normal tissues from patients (Data S1). We found that phospho-PP2A/C (Y307), α4, cancerous inhibitor of protein phosphatase 2A (CIP2A), Akt, ezrin, phospho-ezrin (T567), 14-3-3, and focal adhesion kinase (FAK) showed increased expression levels in carcinoma tissues relative to normal tissues, while phospho-Akt (T308) showed decreased levels. Our study, thus, provides a rationale for targeting PP2A to develop novel therapies and proposes a combination of interrelated biomarkers for the diagnostic evaluation and prognosis prediction in LSCC.
Autoantigens/metabolism* ; Biomarkers, Tumor/metabolism* ; Carcinoma, Squamous Cell/metabolism* ; Case-Control Studies ; Cytoskeletal Proteins/metabolism* ; Focal Adhesion Kinase 1/metabolism* ; Gene Expression Profiling ; Gene Expression Regulation ; Gene Expression Regulation, Neoplastic ; Humans ; Intracellular Signaling Peptides and Proteins/metabolism* ; Laryngeal Neoplasms/metabolism* ; Larynx/metabolism* ; Membrane Proteins/metabolism* ; Phosphorylation ; Protein Phosphatase 2/metabolism*

Hematologic Neoplasms ; Humans ; Intracellular Signaling Peptides and Proteins

OBJECTIVETo investigate the synergistic effect of rapamycin (RPM) and PD98059 on human colorectal cancer cells and its potential mechanisms.

METHODSThree human colorectal cancer cell lines SW480, HCT116 and HT29 were treated with RPM 10 nmol/L, PD98059 (10 micromol/L, 20 micromol/L, 40 micromol/L, 50 micromol/L), or RPM plus PD98059, respectively, and the sensitivity was analyzed by MTT assay. The cell cycle progression was evaluated by flow cytometry. Western blotting analysis was performed to examine the total and phosphorylated levels of mammalian target of rapamycin (mTOR) and its downstream translational signaling intermediates, 70 kDa ribosomal protein S6 kinase (p70s6k) and eukaryotic initiation factor 4E-binding protein 1 (4E-BP1).

RESULTSBoth RPM and PD98059 could inhibit viability of the three cell lines. The anti-proliferative effect of PD98059 exhibited a time/dose dependent manner and was strengthen by RPM. All the treatment with RPM, PD98059, and RPM + PD98059 induced arrest of cell cycle, although the arrest was confined at different cell cycle phases. In addition to their effect on proliferation and cell cycle, both inhibitors also reduced phosphorylation levels of mTOR, p70s6k, and 4E-BP1, as well as total 4E-BP1 levels in SW480 and HCT116 cells. That effect was reinforced when cells were treated with RPM plus PD98059 simultaneously, whereas total protein levels of mTOR and p70s6k remained unchanged.

CONCLUSIONRPM and PD98059 inhibit proliferation of colorectal cancer cells synergistically, and induce cell cycle arrest. The modulation of mammalian target of rapamycin signaling pathway is involved in its potential mechanisms.

Adaptor Proteins, Signal Transducing ; metabolism ; Antibiotics, Antineoplastic ; pharmacology ; Calcium-Calmodulin-Dependent Protein Kinases ; antagonists & inhibitors ; Cell Cycle ; drug effects ; Cell Proliferation ; Colorectal Neoplasms ; metabolism ; pathology ; Drug Synergism ; Flavonoids ; pharmacology ; HCT116 Cells ; HT29 Cells ; Humans ; Intracellular Signaling Peptides and Proteins ; antagonists & inhibitors ; metabolism ; Phosphoproteins ; metabolism ; Phosphorylation ; Protein-Serine-Threonine Kinases ; antagonists & inhibitors ; metabolism ; Ribosomal Protein S6 Kinases, 70-kDa ; metabolism ; Signal Transduction ; Sirolimus ; pharmacology ; TOR Serine-Threonine Kinases

The effects of (-)-epigallocatechin gallate (EGCG) on pacemaker activities of cultured interstitial cells of Cajal (ICC) from murine small intestine were investigated using whole-cell patch-clamp technique at 30degrees C and Ca2+ image analysis. ICC generated spontaneous pacemaker currents at a holding potential of -70 mV. The treatment of ICC with EGCG resulted in a dose-dependent decrease in the frequency and amplitude of pacemaker currents. SQ-22536, an adenylate cyclase inhibitor, and ODQ, a guanylate cyclase inhibitor, did not inhibit the effects of EGCG. EGCG-induced effects on pacemaker currents were not inhibited by glibenclamide, an ATP-sensitive K+ channel blocker and TEA, a Ca2+-activated K+ channel blocker. Also, we found that EGCG inhibited the spontaneous [Ca2+]i oscillations in cultured ICC. In conclusion, EGCG inhibited the pacemaker activity of ICC and reduced [Ca2+]i oscillations by cAMP-, cGMP-, ATP-sensitive K+channel-independent manner.
Adenine ; Adenylyl Cyclases ; Animals ; Gastrointestinal Motility ; Glyburide ; Guanylate Cyclase ; Interstitial Cells of Cajal ; Intestine, Small ; Mice ; Patch-Clamp Techniques ; Tea

Child ; Humans ; Intracellular Signaling Peptides and Proteins ; Mutation ; Pancytopenia

OBJECTIVES: To observe the electrophysiological changes of astrocytes in the process of hyperoxia induced apoptosis and analyze the relationship between electrophysiological characteristics and morphological changes. METHODS: Astrocytes were exposed to 90% hyperoxia for 12-72 h. The electrophysiological characteristics of astrocytes in each group were detected by patch clamp technique, and the morphological characteristics of astrocytes were observed at the same time. Then the same batch of astrocytes were collected, and the expression levels of caspase-1, caspase-3, gasdermin D (GSDMD) and gasdermin E (GSDME) were detected by Western blotting. RESULTS: From 12 h to 72 h after hyperoxia exposure, the inward current was significantly lower than that of the control group (<0.05), while the outward current was significantly decreased at 12 h and increased at 48 h (<0.05). There was no significant difference between 24 h or 72 h after hyperoxia exposure and the control group (>0.05). At each time point, the morphology of cells changed correspondingly. Western blotting showed that the expression of caspase-1 was increased significantly at 24 h and decreased significantly at 72 h after hyperoxia exposure (<0.05); the expression of GSDMD was increased at 12 h and decreased gradually from 24 h to 72 h after hyperoxia exposure (<0.05); the expression of caspase-3 did not change significantly at 12 h and 24 h after hyperoxia exposure (>0.05), but began to decrease at 48 h (<0.05); GSDME increased gradually at 24 h after hyperoxia exposure (<0.05). CONCLUSIONS Under hyperoxia exposure, the ion channels of astrocytes are damaged, which can maintain the dysfunction of ion homeostasis, activate GSDME, induce the damaged cells to break away from the apoptotic pathway, and mediate the pyroptosis.
Apoptosis ; Astrocytes ; Caspase 1 ; Humans ; Hyperoxia ; Intracellular Signaling Peptides and Proteins ; Neoplasm Proteins ; Phosphate-Binding Proteins ; Pyroptosis

Effects of Ultratiolet (UV) light was studied in isolated thoracic aortae of rabbits and porcine coronary arteries. The following results were obtained. 1) Radiation of UV light did not affect both arterial rings in resting tension. 2) Both arterial preparations contracted with various vasoconstrictors (KCI,NE,PE,BayK 8644 and (+S202 etc.) were relaxed by UV light radiation in a radiation time-dependent fashion. 3) The magnitudes of the relaxation were not significantly different in both the rings with or without intact endothelium. 4) MB and LY markedldy reduced the UV light-induced relaxation in both the rings. 5) PP significantly attenuated the UV light-induced relaxation of rabbit thoracic aorta, but did not affect that of porcine coronary artery. 6) The UV Light-induced relaxation of porcine coronary artery was significantly attenuated by DT or NF, while that of rabbit thoracic aorta was not. 7) (+)S202 significantly potentiated the UV light-induced relaxation of porcine coronary artery contracted with KCI or Hist. Above results suggest that the UV light-induced relaxation of vascular smooth muscles is independent on the endothelium, and the relaxation results from primarily activation of guanylyl cyclase and is in part related to adenylyl cyclase and calcium metabolism. In adddition, a dihydropyridine calcium agonist, (+)S202, may sensitize vascular smooth muscle to the relaxing effect of UV light through some unknown mechanism.
Adenylyl Cyclases ; Aorta, Thoracic ; Calcium* ; Coronary Vessels ; Endothelium ; Guanylate Cyclase ; Metabolism ; Muscle, Smooth* ; Muscle, Smooth, Vascular ; Rabbits ; Relaxation* ; Ultraviolet Rays ; Vasoconstrictor Agents