Emergency attendances and hospitalisations for complications after transrectal ultrasound-guided prostate biopsies: a five-year retrospective multicentre study.

INTRODUCTION: Transrectal ultrasound-guided (TRUS) prostate biopsy is an established procedure for diagnosis of prostate cancer. Complications after TRUS biopsy are not well reported in Hong Kong. This study evaluated the 5-year incidences of TRUS biopsy complications and potential risk factors for those complications. METHODS: This was a retrospective review of biopsies performed from 2013 to 2017 in two local hospitals, using data retrieved from electronic medical records. The primary outcome was the occurrence of complications requiring either emergency attendances or hospitalisations within 30 days after biopsy. Potential risk factors were examined using multiple logistic regression analysis. RESULTS: In total, 1699 men were included (mean age ± standard deviation: 67 ± 7 years; median prostate-specific antigen level: 7.9 µg/L [interquartile range, 5.5-12.6 µg/L]); 4.3% had pre-biopsy bacteriuria. Overall, 5.7% and 3.8% of post-biopsy complications required emergency attendances and hospitalisations, respectively. Gross haematuria and rectal bleeding requiring emergency attendances developed in 2.1% and 0.4% of men; 0.8% and 0.4% required hospitalisations. Furthermore, 1.5% of men developed acute urinary retention requiring hospitalisations; 1.9% and 1.2% had post-biopsy infections requiring emergency attendances and hospitalisations, respectively, and 0.9% had urosepsis requiring hospitalisations. Prostate volume >48 cc was associated with an increased risk of post-biopsy retention (odds ratio 2.75, 95% confidence interval: 1.23-4.17). CONCLUSIONS: The rate of overall complications after TRUS biopsy was low. The most common complications requiring emergency attendances and hospitalisations were gross haematuria and acute urinary retention, respectively. Prostate volume >48 cc increased the risk of post-biopsy urinary retention.

Dual Role of Cyanidin-3-glucoside on the Differentiation of Bone Cells.

Cyanidin-3-glucoside (C3G) is one of the major components of anthocyanin, a water-soluble phytochemical. Recent studies demonstrated the chemopreventive and chemotherapeutic activities of C3G in various conditions, including cancer, although the precise effects of C3G on osteoclast and osteoblast differentiation remain unclear. Here, we investigated the role of C3G in the differentiation of bone-associated cells and its underlying mechanism. C3G inhibited receptor activator of nuclear factor kappa-B ligand (RANKL)-mediated osteoclast differentiation and formation in a dose-dependent manner and downregulated the expression of osteoclast differentiation marker genes. Pretreatment with C3G considerably reduced the induction of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 mitogen-activated kinases activation by RANKL in osteoclast precursor cells. Furthermore, C3G dramatically inhibited the expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1, which are important transcription factors for osteoclast differentiation and activation. The formation of osteoclasts in coculture of bone marrow cells and calvaria-derived osteoblasts was also inhibited by C3G treatment, although the expression of macrophage colony-stimulating factor and RANKL (master factors for osteoclast differentiation and formation) and osteoprotegerin (a decoy receptor for RANKL) on osteoblasts was unaffected. The inhibitory effect of C3G on osteoclastogenesis is therefore targeted specifically to osteoclasts but not osteoblasts. Moreover, analysis of the expression levels of osteoblast differentiation marker genes and alizarin red staining showed that osteoblast differentiation and matrix formation increased after C3G treatment. Taken together, these results strongly suggest that C3G has a dual role in bone metabolism, as an effective inhibitor of osteoclast differentiation but also as an activator of osteoblast differentiation. Therefore, C3G may be used as a potent preventive or therapeutic agent for bone-related diseases, such as osteoporosis, rheumatoid arthritis, and periodontitis.

Rubi Fructus (Rubus coreanus) activates the expression of thermogenic genes in vivo and in vitro.

OBJECTIVE: To investigate the anti-obesity effect of Rubi Fructus (RF) extract using brown adipose tissue (BAT) and primary brown preadipocytes in vivo and in vitro. METHODS: Male C57BL/6 J mice (n=5 per group) were fed a high-fat diet (HFD) for 10 weeks with or without RF. Brown preadipocytes from the interscapular BAT of mice (age, post-natal days 1-3) were cultured with differentiation media (DM) including isobutylmethylxanthine, dexamethasone, T3, indomethacin and insulin with or without RF. RESULTS: In HFD-induced obese C57BL/6 J mice, long-term RF treatment significantly reduced weight gain as well as the weights of the white adipose tissue, liver and spleen. Serum levels of total cholesterol and low-density lipoprotein cholesterol were also reduced in the HFD group which received RF treatment. Furthermore, RF induced thermogenic-, adipogenic- and mitochondria-related gene expressions in BAT. In primary brown adipocytes, RF effectively stimulated the expressions of thermogenic- and mitochondria-related genes. In addition, to examine whether LIPIN1, a regulator of adipocyte differentiation, is regulated by RF, Lipin1 small interfering RNA (siRNA) and RF were pretreated in primary brown adipocytes. Pretreatment with Lipin1 siRNA and RF downregulated the DM-induced expression levels of thermogenic- and mitochondria-related genes. Moreover, RF markedly upregulated AMP-activated protein kinase. Our study shows that RF is capable of stimulating the differentiation of brown adipocytes through the modulation of thermogenic genes. CONCLUSIONS: This study demonstrates that RF prevents the development of obesity in mice fed with a HFD and that it is also capable of stimulating the differentiation of brown adipocytes through the modulation of thermogenic genes, which suggests that RF has potential as a therapeutic application for the treatment or prevention of obesity.

Augmentation of NAD(+) by NQO1 attenuates cisplatin-mediated hearing impairment.

Cisplatin (cis-diaminedichloroplatinum-II) is an extensively used chemotherapeutic agent, and one of its most adverse effects is ototoxicity. A number of studies have demonstrated that these effects are related to oxidative stress and DNA damage. However, the precise mechanism underlying cisplatin-associated ototoxicity is still unclear. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as a key regulator of cellular energy metabolism and homeostasis. Here, we demonstrate for the first time that, in cisplatin-mediated ototoxicity, the levels and activities of SIRT1 are suppressed by the reduction of intracellular NAD(+) levels. We provide evidence that the decrease in SIRT1 activity and expression facilitated by increasing poly(ADP-ribose) transferase (PARP)-1 activation and microRNA-34a through p53 activation aggravates cisplatin-mediated ototoxicity. Moreover, we show that the induction of cellular NAD(+) levels using ß-lapachone (ß-Lap), whose intracellular target is NQO1, prevents the toxic effects of cisplatin through the regulation of PARP-1 and SIRT1 activity. These results suggest that direct modulation of cellular NAD(+) levels by pharmacological agents could be a promising therapeutic approach for protection from cisplatin-induced ototoxicity.

Gingko biloba extracts protect auditory hair cells from cisplatin-induced ototoxicity by inhibiting perturbation of gap junctional intercellular communication.

Gap junctional intercellular communication (GJIC) may play an important role in the hearing process. Cisplatin is an anticancer drug that causes hearing loss and Gingko biloba extracts (EGb 761) have been used as an antioxidant and enhancer for GJIC. The purpose of this study was to examine the efficiency of EGb 761 in protecting against cisplatin-induced apoptosis and disturbance of GJIC. House Ear Institute-Organ of Corti 1 auditory cells were cultured and treated with cisplatin (50 µM) and EGb (300 µg/ml) for 24h, and then analyzed by immunocytochemistry (Annexin V/propidium iodide) and Western blots. GJIC was evaluated by scrape-loading dye transfer (SLDT). Basal turn organ of Corti (oC) explants from neonatal (p3) rats were exposed to cisplatin (1-10 µM) and EGb (50-400 µg/ml). The number of intact hair cells was counted by co-labeling with phalloidin and MyoVIIa. EGb prevented cisplatin-induced apoptosis in immunostaining and decreased caspase 3 and poly-ADP-ribose polymerase bands, which were increased in cisplatin-treated cells in Western blots. EGb prevented abnormal intracellular locations of connexin (Cx) 26, 30, 31, and 43 in cells treated with cisplatin and increased quantities of Cx bands. EGb also prevented cisplatin-induced disturbance of GJIC in SLDT. In oC explants, EGb significantly prevented hair cell damage induced by cisplatin. In animal studies, EGb significantly prevented cisplatin-induced hearing loss across 16 and 32 kHz. These results show that cisplatin induces ototoxicity including hearing loss as well as down-regulation of GJIC and inhibition of Cxs in auditory cells. EGb prevents hearing loss in cisplatin-treated rats by inhibiting down-regulation of Cx expression and GJIC. The disturbance of GJIC or Cx expression may be one of the important mechanisms of cisplatin-induced ototoxicity.

Superselective embolisation of bilateral superior vesical arteries for management of haemorrhagic cystitis.

Bladder haemorrhage is common and sometimes life-threatening. Management options include bladder irrigation and supportive transfusion, intravesical instillation, endourological intervention, and surgical intervention which has poor success and high morbidity rates. Percutaneous arterial embolisation offers another minimally invasive option. We report two patients with severe haemorrhagic cystitis treated with superselective embolisation of bilateral superior vesical arteries. The technique is safe and effective for achieving immediate control of refractory bladder haemorrhage. The long-term efficacy of the procedure requires further investigation.

Effect of a DanJeon Breathing Exercise Program on the quality of life in patients with kidney transplants.

This quasi-experimental study attempted to show that nursing intervention using the DanJeon Breathing Exercise Program (DJBEP) improved the quality of life of recipients after kidney transplantation. DJBEP progressed in three steps. We prospectively included 29 outpatient volunteers: experimental group: n = 15; control group: n = 14. DJBEP derived from the Roy's adaptation model decreased both the stress and the uncertainty of kidney transplantation recipients. It has also been shown to restore serum cholesterol and serum creatinine levels and enhance strength and flexibility. Simultaneously, self-esteem was enhanced, and eventually adaptation was promoted both physiologically and psychologically. The quality of life of kidney transplantation recipients was enhanced. DJBEP played an effective role as a nursing intervention to promote the quality of life of kidney transplant patients by increasing their physiological and psychological status.

Flunarizine induces Nrf2-mediated transcriptional activation of heme oxygenase-1 in protection of auditory cells from cisplatin.

We investigated the cytoprotective mechanisms of flunarizine in cisplatin-induced death of auditory cells. Concomitant with an increase in viability, treatment with flunarizine resulted in a marked dissociation of Nrf2/Keap1 and subsequent intranuclear translocation of Nrf2, which was mediated by PI3K-Akt signaling. Overexpression of Nrf2 protected cells from cisplatin along with transcriptional activation of ARE to generate heme oxygenase-1 (HO-1). Pretreatment with flunarizine predominantly increased the transcriptional activity of HO-1 among Nrf2-driven transcripts, including HO-1, NQO1, GCLC, GCLM, GST micro-1, and GSTA4. Furthermore, both pharmacological inhibition and siRNA transfection of HO-1 completely abolished the flunarizine-mediated protection of HEI-OC1 cells and the primary rat (P2) organ of Corti explants from cisplatin. These results suggest that Nrf2-driven transcriptional activation of ARE through PI3K-Akt signaling augments the generation of HO-1, which may be a critically important determinant in cellular response toward cisplatin and the cytoprotective effect of flunarizine against cisplatin.

Nitric oxide prevents the IFN-gamma/LPS-induced hepatotoxicity in a protein kinase G-independent manner.

Although it has been well known that the role of LPS on hepatotoxicity is mediated through TNF-alpha, the direct cytotoxic effect of LPS on IFN-gamma-primed hepatocytes has not yet been clearly demonstrated. Here, we demonstrate that the IFN-gamma-mediated death of murine embryonic liver BNL CL2 cells is potentiated by LPS (0.5 microg/ml). In addition, an exogenous NO donor, sodium nitroprusside (SNP) significantly prevents cell death induced by IFN-gamma alone or IFN-gamma plus LPS (IFN-gamma/LPS) in a dose-dependent manner over 25 microM. SNP significantly blocked the death of BNL CL2 cells only when it was added within 12 hr after treatment of IFN-gamma and IFN-gamma/LPS. The preventive effect of SNP occurred in parallel with the suppression of caspase 3-like protease activation. We have also demonstrated that a relatively high concentration as well as an appropriate period of exposure to NO may be critical to maintain cell viability from the cytotoxic effect of IFN-gamma and IFN-gamma/LPS. Furthermore, the preventive effect of SNP on IFN-gamma/LPS-induced cell death is mediated by a protein kinase G (PKG)-independent manner.

Protective effects of Debo on zinc-induced apoptosis of C6 glial cells via modulation of intracellular antioxidant, reduced glutathione.

In the present study, the mechanical basis of a traditional herbal prescription, Debo. on cytotoxic damage of the brain cells including C6 glial and PC12 cells has been studied. Traditionally, Debo has been employed for the purpose of preventing responses to trauma, ischemia, and other diseases in the nervous system. C6 glial cells were exposed to oxidative stress through the imployment of ZnCl2, and generates H2O2 and hydroxyl radicals by fenton reaction. ZnCl2-induced death of C6 glial cells, which was revealed as apoptosis by chromatin condensation as well as DNA fragmentation. Pretreatment of Debo significantly prevented apoptotic death of C6 glial cells via inhibition of H2O, generation as well as the recovering of an antioxidant, reduced glutathione (GSH). Also, deprivation of serum and glucose, found in ischemia, deceased the viability of PC12 cells up to 60% via generation of H2O2. However, Debo significantly protected cells from ischemic damage through decrease in H2O, generation. Furthermore, Debo markedly inhibited the transcriptional activation of NF-kappaB by ZnCI, in C6 glial cells. These results suggest that Debo may function as an antioxidant system against free radicals and be applicable to protect brain cells against oxidative or ischemic stresses.

Danchunhwan water extract prevents apoptotic death by peroxynitrite and nitric oxide in human dopaminergic neuroblastoma SH-SY5Y cells.

In the present study, the protective effects of Danchunhwan on the cytotoxicity by peroxynitrite and nitric oxide (NO) were investigated in human dopaminergic neuroblastoma SH-SYSY cells. Danchunhwan has been used to treat infarction and cerebrovascular diseases in Oriental medicine for centuries. Cells were pretreated with Danchunhwan and exposed to sodium nitroprusside (SNP), an NO donor, and 3-morpholinosydnonimine (SIN-1) which simultaneously generates NO and superoxide, thus possibly forming peroxynitrite. Exposure of cells to SIN-1 for 24 hr induced 75% of apoptotic cell death, as evaluated by ladder-pattern fragmentation of genomic DNA and characteristic of apoptosis using 4', 6-diamidino-2-phenylinol (DAPI). However, pretreatment of SH-SY5Y cells with Danchunhwan inhibited the apoptotic cell death in a dose-dependent manner. Even though Danchunhwan was washed out after preincubation for 12 hr, cells were still remained to be resistant against cytotoxicity of SIN-1. It also inhibited SIN-1-induced activation of caspase 3-like protease in a dose-dependent fashion. Furthermore, Danchunhwan recovered the levels of intracellular antioxidant system, reduced glutathione (GSH) (83%), which was decreased by the addition of SIN-1 (63%). Taken together, we suggest that Danchunhwan protects human neuroblastoma SH-SY5Y cells from apoptotic death by free radicals including peroxynitrite and NO via generation of antioxidant, GSH.

Sodium nitroprusside induces apoptosis of H9C2 cardiac muscle cells in a c-Jun N-terminal kinase-dependent manner.

Sodium nitroprusside (SNP) induces apoptosis in H9C2 cardiac muscle cells. Treatment with an exogenous NO donor SNP (2 mM) to H9C2 cells resulted in apoptotic morphological changes; a bright blue-fluorescent condensed nuclei and chromatin fragmentation by fluorescence microscope of Hoechst 33258-staining. The activity of caspase-3 like protease was increased during SNP-induced cell death. However, the activity of caspase-1 like protease was not affected by SNP. Pretreatment with Z-VAD-FMK (a pan-caspase inhibitor) or Ac-DEVD-CHO (a specific caspase-3 inhibitor) abrogated the SNP-induced cell death. SNP markedly activated three MAP kinases (JNK/SAPK, ERK and p38 MAP kinase) in the cardiac muscle cells. In this study, selective inhibition of the ERK or p38 MAPK pathway (by PD98059 or SB203580, respectively) had no effect on the extent of SNP-induced apoptosis in cardiac muscle cells. In contrast, inhibition of the JNK pathway by transfection of a dominant negative mutant of JNK markedly reduced the extent of SNP-induced cell death. Taken together, we suggest that JNK/SAPK will be related to SNP-induced apoptosis of H9C2 cardiac muscle cells.

Gamma-interferon (IFN-gamma) augments apoptotic response to mistletoe lectin-II via upregulation of Fas/Fas L expression and caspase activation in human myeloid U937 cells.

Mistletoe lectin-II, a major composition of Korean mistletoe (Viscum album coloratum), is known as a potent apoptosis inducer. The previous research has demonstrated that Korean mistletoe lectin-II induces apoptosis via c-Jun N terminal kinase (JNK) activation in human myeloid U937 cells. The purpose of this research is to prove the synergistic action of mistletoe lectin-II and interferon-gamma (IFN-gamma) in the apoptotic cytotoxicity of U937. When U937 cells were treated with mistletoe lectin-II after being differentiated by IFN-gamma, the proteolytic activity of caspase-3 and 9 was markedly elevated and that of caspase-8 was prolonged for 18 hr. The activation of caspase-3-like protease requires the earlier cleavage of poly(ADP-ribose) polymerase(PARP). Caspase-1 was, however, not activated during the resting phase and nor in IFN-gamma-differentiated U937 cells. Western blot analysis revealed that, in IFN-gamma-differentiated U937 cells, the expression of Fas (CD95/APO-1) & Fas ligand(FasL) increases the apoptotic sensitivity against Mistletoe lectin-II. Fas (CD95/APO-1) & FasL were not significantly induced solely by mistletoe lectin-II. Furthermore the activity of JNK1 in U937 cells was also markedly increased with IFN-gamma-differentiation, compared to that of the control. These results suggest that the IFN-gamma-differentiation of U937 cells increases the susceptibility to mistletoe lectin-II-induced apoptosis.

Protective effects of morphine in peroxynitrite-induced apoptosis of primary rat neonatal astrocytes: potential involvement of G protein and phosphatidylinositol 3-kinase (PI3 kinase).

Opiates, such as morphine, have been used extensively in the clinical management of pain due to their potent analgesic effect. Astrocytes, representing a major non-neuronal cell population in the CNS, contain opioid receptors that are actively involved in several brain functions. This study was designed to evaluate the effects by which morphine, a preferential mu-opioid receptor agonist, contributes to cytotoxicity of nitric oxide (NO) species, including NO and peroxynitrite (ONOO-), in primary rat neonatal astrocytes. Primary astrocytes isolated from the cerebral cortex of 1- to 2-day-old Sprague-Dawley rats were treated with morphine, naloxone, and 3-morpholinosydnonimine (SIN-1), a donor of peroxynitrite. Morphine significantly protected primary rat astrocytes from apoptosis mediated by sodium nitroprusside, an NO donor, and SIN-1 in a dose-dependent manner, whereas it did not in other types of cells including C6 glioma, RAW 264.7, and HL-60 cells. Moreover, naloxone antagonized the protective effects of morphine on SIN-1-induced apoptosis. Morphine also inhibited the nuclear condensation and fragmentation of SIN-1-treated cells that was antagonized by naloxone pretreatment. The protective role of morphine in SIN-1-induced apoptosis was dependent on an intracellular antioxidant system such as GSH. Furthermore, the effects of morphine on SIN-1-induced cytotoxicity were prohibited by pretreatment with the G(i) protein inhibitor, pertussis toxin, and the phosphatidylinositol 3-kinase (PI3 kinase) inhibitors, wortmannin and LY294002. Taken together, these results suggest that morphine may protect primary rat astrocytes from apoptosis by NO species via the signaling cascades that involve both G protein and PI3 kinase.

Radially expanding trocar: a less painful alternative for laparoscopic surgery.

BACKGROUND AND PURPOSE: One advantage of minimal-access surgery is that it produces less pain. A radially expanding trocar has been claimed to reduce pain further. We aimed to evaluate this claim. PATIENTS AND METHODS: This was a randomized controlled single-blind clinical trial. Fifty-four patients who underwent laparoscopic cholecystectomy at the Department of Surgery, United Christian Hospital, Hong Kong, between July 1997 and September 1998 were randomized into either the study group or the control group. The radially expanding 10-mm trocar was used for the epigastric port in the study group. The conventional 10-mm metal trocar was used similarly in the control group. The operation was otherwise performed with a standardized technique. Another conventional 10-mm metal trocar was used for the subumbilical port for all patients. Pain was measured using a visual analog scale. Pain scores for the epigastric port and subumbilical port were documented for 3 days after the surgery. RESULTS: There was no difference in age, sex, diagnoses, operating time, or conversion rate. There was consistently no difference in the pain experienced in the subumbilical wound, whereas pain at the epigastric wound was consistently less with the radially expanding trocar (p < 0.05). CONCLUSION: The radially expanding trocar produces less early postoperative pain than the conventional metal trocar.

Activation of c-Jun N-terminal kinase 1 (JNK1) in mistletoe lectin II-induced apoptosis of human myeloleukemic U937 cells.

Extracts of mistletoe (Viscum album var. coloratum) have been used for several decades as an anticancer immunomodulating agent in clinical fields. However, the mechanism by which the plant extracts kill tumor cells has remained elusive. We investigated the direct effects of beta-galactoside- and N-acetyl-d-galactosamine-specific mistletoe lectin II in inducing apoptotic death of U937 cells. Three distinct components of mistletoe, including beta-galactoside- and N-acetyl-D-galactosamine-specific lectin II (60 kDa), polysaccharides, and viscotoxin (5 kDa), induced apoptotic cell death, characterized by DNA ladder pattern fragmentation of U937 cells at 12 hr after treatment. Consistent with apoptosis of the cells, mistletoe extracts markedly increased the phosphotransferase activity of c-Jun N-terminal kinase 1 (JNK1)/stress-activated protein kinase (SAPK) in U937 cells. Among the three components, lectin II was the most potent in inducing apoptosis as well as JNK1 activation of U937 cells in a dose- and time-dependent manner. Catalytic activation of JNK1 induced by mistletoe lectin II was inhibited by the addition of peptide aC-DEVD-CHO, but not by aC-YVAD-CHO. In addition, mistletoe lectin II induced apoptosis in a variety of cell types including Jurkat T cells, RAW 264.7 cells, HL-60 cells, DLD-1 cells, and primary acute myelocytic leukemic cells.

The water extract of Jagamchotang protects the ischemia/reperfusion-induced cytotoxicity of rat neonatal myocardial cells via generation of nitric oxide.

Jagamchotang has been used for treatment of ischemic myocardial diseases in Chinese traditional medicine. However, little is known about the mechanism by which Jagamchotang rescues myocardial cells from ischemic damages. To elucidate the protective mechanisms, the effects of Jagamchotang on ischemia/reperfusion-induced cytotoxicity and generation of nitric oxide (NO) are investigated in primary neonatal myocardial cells. Ischemia/reperfusion itself induces severe myocardial cell death in vitro. However, treatment of the cells with Jagamchotang significantly reduces both ischemia/reperfusion-induced myocardial cell death and LDH release. In addition, pretreatment of Jagamchotang before reperfusion recovers the lose of beating rates after ischemia/reperfusion. For a while, the water extract of Jagamchotang stimulates myocardial cells in ischemic condition to produce nitric oxide (NO) in a dose dependent manner and it protects the damage of myocardial cells. Furthermore, the protective effects of the water extract of Jagamchotang is mimicked by treatment of sodium nitroprusside, an exogenous NO donor. NG-monomethyi-L-argine (NGMMA), a specific inhibitor of nitric oxide synthase (NOS), significantly blocks the protective effects of Jagamchotang on the cells after ischemia/reperfusion. Taken together, we suggest that the protective effects of Jagamchotang against ischemia/reperfusion-induced myocardial damages may be mediated by NO production during ischemic condition.

Dexamethasone suppresses tumor necrosis factor-alpha-induced apoptosis in osteoblasts: possible role for ceramide.

Ceramide has been proposed as a second messenger molecule implicated in a variety of biological processes, including apoptosis. Recently, it has been reported that tumor necrosis factor-alpha (TNF-alpha) activates the release of ceramide and that ceramide acts as a mediator for the TNF-alpha-induced stimulation of the binding affinity of nuclear factor-KB (NF-KB), a ubiquitous transcription factor of particular importance in immune and inflammatory responses. In this study we demonstrate that dexamethasone, which reduces the production of ceramide, significantly inhibits TNF-alpha-induced activation of NF-KB, c-Jun N-terminal kinase, also known as stress-activating protein kinase, caspase-3-like cysteine protease, redistribution of cytochrome c, and apoptosis in MC3T3E1 osteoblasts. Compared with TNF-alpha-induced JNK activation, ceramide elicits a more rapid activation of JNK within 30 min. C2-ceramide activates NF-KB and caspase-3 like protease to the same degree and with kinetics similar to those of TNF-alpha. This study provides evidence that the release of ceramide may be required as a second messenger in TNF-alpha-induced apoptosis. These results also suggest a regulatory role for dexamethasone in TNF-alpha-induced apoptosis via inhibition of ceramide release. Therefore, our in vitro results suggest that therapies targeted at the inhibition of ceramide release may abrogate inflammatory processes in TNF-alpha-related diseases, including rheumatoid arthritis and periodontitis.

Cyclic adenosine monophosphate inhibits ursolic acid-induced apoptosis via activation of protein kinase A in human leukaemic HL-60 cells.

This study was designed to investigate the effect of cAMP on ursolic acid-induced apoptosis of HL-60 cells. Ursolic acid decreased the viability of the cells in a dose-dependent manner, which was revealed as an apototic process characterized by ladder-pattern DNA fragmentation in agarose gel electrophoresis and segmented nuclei in DAPI-sulpharhodamin 101 staining. Ursolic acid-induced apoptosis of the cells was markedly inhibited by the addition of cAMP-elevating agents including DB-cAMP, CPT-cAMP, 8-Br-cAMP and forskolin. These results were further evidenced by the fact that inhibitors of cAMP-dependent protein kinase including H89 and KT5720 completely inhibited the cAMP-mediated rescue of HL-60 cells from ursolic acid-induced apoptosis. In addition, differentiating agents of the cells such as dimethyl sulfoxide and retinoic acid did not affect the ursolic acid-induced apoptosis of HL-60 cells. These results suggest that signaling pathway of cAMP-dependent activation of protein kinase A may affect the responsiveness of tumor cells upon ursolic acid.

LPS induces direct death of IFN-gamma primed murine embryonic hepatocyte, BNL CL2 cells in a TNF-alpha independent manner.

Although it has been well known that the role of LPS on liver damage is mediated through TNF-alpha, the mechanism by which LPS modulates the cytotoxicity of IFN-gamma on hepatocytes has not yet been clearly demonstrated. Here, we demonstrate that IFN-gamma mediated apoptosis in murine embryonic hepatocyte BNL CL2 cells is potentiated by the addition of LPS (0.5 microg/ml). Consistently, LPS markedly increases the catalytic activity of caspase 3-like protease but not caspase 1-like protease in IFN-gamma treated cells. In addition, TNF-alpha alone does not affect cell viability but rather it potentiates the cytotoxic effect of IFN-gamma on BNL CL2 cells. However, the cell viability of IFN-gamma/LPS treated cells is affected by the addition of polymyxin B but not by TNF binding protein I (TNF-BPI). These data suggest that the lipid moiety of LPS may mediate direct cytotoxicity of BNL CL2 cells in a TNF-alpha independent manner.