Hon Ping Ma

Thrombin Induces NF-κB Activation and IL-8/CXCL8 Expression in Lung Epithelial Cells by a Rac1-dependent PI3K/Akt Pathway

We previously showed that thrombin induces interleukin (IL)-8/CXCL8 expression via the protein kinase C (PKC)α/c-Src-dependent IκB kinase α/β (IKKα/β)/NF-κB signaling pathway in human lung epithelial cells. In this study, we further investigated the roles of Rac1, phosphoinositide 3-kinase (PI3K), and Akt in thrombin-induced NF-κB activation and IL-8/CXCL8 expression. Thrombin-induced IL-8/CXCL8 release and IL-8/CXCL8-luciferase activity were attenuated by a PI3K inhibitor (LY294002), an Akt inhibitor (1-l-6-hydroxymethyl-chiro-inositol-2-((R)-2-O-methyl-3-O-octadecylcarbonate)), and the dominant negative mutants of Rac1 (RacN17) and Akt (AktDN). Treatment of cells with thrombin caused activation of Rac and Akt. The thrombin-induced increase in Akt activation was inhibited by RacN17 and LY294002. Stimulation of cells with thrombin resulted in increases in IKKα/β activation and κB-luciferase activity; these effects were inhibited by RacN17, LY294002, an Akt inhibitor, and AktDN. Treatment of cells with thrombin induced Gβγ, p85α, and Rac1 complex formation in a time-dependent manner. These results imply that thrombin activates the Rac1/PI3K/Akt pathway through formation of the Gβγ, Rac1, and p85α complex to induce IKKα/β activation, NF-κB transactivation, and IL-8/CXCL8 expression in human lung epithelial cells.

Silibinin inhibits the invasion of IL-6-stimulated colon cancer cells via selective JNK/AP-1/MMP-2 modulation in vitro.

Silibinin is a flavonoid with antihepatotoxic properties and pleiotropic anticancer capabilities. This study investigated silibinin inhibition of cell invasion by down-regulating matrix metalloproteinase-2 (MMP-2) expression, via attenuation of activator protein-1 (AP-1) in IL-6-stimulated LoVo colon cancer cells. Western blot data showed that the expression of MMP-2 protein was reduced 1.6- or 1.7-fold over the control by treatment with silibinin or JNK inhibitor in the models. Similar results were revealed in zymography and confocal microscopy. Pretreatment with silibinin also abolished the binding activity of AP-1 and MMP-2 promoter activity via AP-1 binding, as observed by EMSA and luciferase assay. Finally, a [(3)H]-thymidine incorporation proliferation assay and cell migration assay demonstrated that silibinin inhibited IL-6-stimulated LoVo cell proliferation and invasion. Taken together, these data indicated that silibinin inhibits LoVo cell invasion with the reduction of MMP-2 presentation by attenuating AP-1 binding activity, suggesting a novel antimetastatic application for silibinin in colon cancer chemoprevention.

Apoptosis signal-regulating kinase 1 in peptidoglycan-induced COX-2 expression in macrophages

In this study, we investigated the role of ASK1 in PGN‐induced C/EBPβ activation and COX‐2 expression in RAW 264.7 macrophages. The PGN‐induced COX‐2 expression was attenuated by the DNs of ASK1, JNK1, JNK2, a JNK inhibitor (SP600125), and an AP‐1 inhibitor (curcumin). PGN caused ASK1 dephosphorylation time‐dependently at Ser967, dissociation from the ASK1‐14‐3‐3 complex, and subsequent ASK1 activation. In addition, PGN activated PP2A and suppression of PP2A by okadaic acid markedly inhibited PGN‐induced ASK1 Ser967 dephosphorylation and COX‐2 expression. PGN induced the activation of the JNK‐AP‐1 signaling cascade downstream of ASK1. PGN‐increased C/EBPβ expression and DNA‐binding activity were inhibited by the ASK1‐JNK‐AP‐1 signaling blockade. COX‐2 promoter luciferase activity induced by PGN was attenuated in cells transfected with the COX‐2 reporter construct possessing the C/EBP‐binding site mutation. In addition, the ASK1‐JNK‐AP‐1‐C/EBPβ cascade was activated in human peripheral mononuclear cells exposure to PGN. The TLR2 agonist Pam3CSK4 was also shown to induce ASK1 Ser967 dephosphorylation, JNK and c‐jun phosphorylation, C/EBPβ activation, and COX‐2 expression in RAW 264.7 macrophages. PGN‐induced COX‐2 promoter luciferase activity was prevented by selective inhibition of TLR2 and c‐Jun in RAW 264.7 macrophages. Our data demonstrate that PGN might activate the TLR2‐mediated PP2A‐ASK1‐JNK‐AP‐1‐C/EBPβ cascade and subsequent COX‐2 expression in RAW 264.7 macrophages.

Functional role of wogonin in anti-angiogenesis.

Constitutive activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway occurs commonly in cancer cells and endothelial cells, and contributes to angiogenesis. Wogonin is a compound with many biologically relevant properties. We previously reported that wogonin blocked IL-6-induced angiogenesis through suppression of VEGF expression, an important regulator of angiogenesis. However, the pathway involved in the suppressive effect of wogonin on IL-6-induced VEGF has not been completely clarified. This study aimed to investigate the molecular mechanisms participating in the suppression of wogonin on IL-6-induced VEGF in vitro, focusing on IL-6R/JAK1/STAT3/VEGF pathway. Both STAT3 siRNA and wogonin treatment resulted in an abolition of the expression of VEGF. Moreover, our data revealed that wogonin treatment after STAT3 knock-down did not further suppress VEGF expression. The addition of IL-6R siRNA or wogonin resulted in a decrease in the expression level of the phosphorylated JAK1 protein. Furthermore, wogonin significantly decreased the amount of phosphorylated STAT3. Finally, by EMSA, wogonin suppressed IL-6-induced STAT3 binding activity in a concentration-dependent manner. Taken together, our results show that wogonin suppresses IL-6-induced VEGF by modulating the IL-6R/JAK1/STAT3 signaling pathway. Based on this study, we suggest that wogonin may provide a new potential therapeutic option for treatment of IL-6-related pathological angiogenesis.

Thrombin‐induced CCN2 expression in human lung fibroblasts requires the c‐Src/JAK2/STAT3 pathway

Thrombin is a multifunctional serine protease and an important fibrotic mediator that induces CCN2 expression. We previously showed that thrombin induces CCN2 expression via an ASK1‐dependent JNK/AP‐1 pathway in human lung fibroblasts. In this study, we further investigated the roles of c‐Src, JAK2, and STAT3 in thrombin‐induced CCN2 expression. Thrombin‐induced CCN2 expression and CCN2‐Luc activity were attenuated by a JAK inhibitor (AG490) and JAK2DN, STAT3DN, and the STAT decoy ODN. Moreover, transfection of cells with a CCN2‐mtSTAT‐Luc construct inhibited thrombin‐induced CCN2‐Luc activity. Treatment of cells with thrombin caused JAK2 phosphorylation at Tyr1007/1008 and STAT3 phosphorylation at Tyr705 in time‐dependent manners. Thrombin‐induced STAT3 phosphorylation was inhibited by AG490 and JAK2DN. Thrombin‐induced STAT3 binding to the CCN2 promoter was analyzed by a DNA‐binding affinity pull‐down assay. In addition, thrombin‐induced CCN2 expression and CCN2‐Luc activity were inhibited by c‐SrcDN and PP2 (an Src inhibitor). Transfection of cells with c‐SrcDN also inhibited thrombin‐induced JAK2 and STAT3 phosphorylation. Taken together, these results indicate that thrombin might activate c‐Src to induce JAK2 activation, which in turn, causes STAT3 activation, and finally induces CCN2 expression in human lung fibroblasts.

Alterations in histone deacetylase 8 lead to cell migration and poor prognosis in breast cancer.

AIMS Alterations in histone proteins can lead to breast tumorigenesis. Selective histone deacetylase 8 (HDAC8) inhibitors with fewer adverse effects have been developed. A more comprehensive study of alterations and its mechanisms in HDAC8 is required. In this study, we investigated mechanisms of dysregulation of HDAC8 expression and its biological role and pathways in breast cancer. MAIN METHODS Alterations in HDAC8 were analyzed in Taiwanese breast cancer patients; and in tissue samples from The Cancer Genome Atlas (TCGA) data set that were derived from Western countries. Knockdown by si-HDAC8, treatment with the HDAC8-specific inhibitor PCI-34051, SRB assays, wound healing, Transwell migration assays, Illumina BeadArray™ arrays and Ingenuity Pathway Analysis (IPA) were performed in breast cancer cells. KEY FINDINGS HDAC8 mRNA expression was upregulated in paired breast cancer tissue from Taiwanese patients and in paired breast cancer tissues from the TCGA data set. Hypomethylation of promoter regions was significantly correlated with HDAC8 mRNA overexpression in 588 breast cancer patients from the TCGA data set and was associated with poor prognosis in early-stage breast cancer. HDAC8 mRNA overexpression was associated with late stages and tumor progression. Wound healing and Transwell migration assays revealed that knockdown by si-HDAC8 or PCI-34051 treatment significantly inhibited breast cancer cell migration. Knockdown by si-HDAC8, Illumina BeadArray™ arrays and IPA found that ID3 and PTP4A2 pathways were regulated by HDAC8 in cancer cell migration. SIGNIFICANCE Hypomethylation of the HDAC8 promoter is correlated with HDAC8 overexpression and breast cancer progression and is a potential prognosis marker and drug target.

Recovery from sleep disturbance precedes that of depression and anxiety following mild traumatic brain injury: a 6-week follow-up study

Objectives The detailed course of mental disorders at the acute and subacute stages of mild traumatic brain injury (mTBI), especially with regard to recovery from sleep disturbances, has not been well characterised. The aim of this study was to determine the course of depression, anxiety and sleep disturbance, following an mTBI. Setting We recruited patients with mTBI from three university hospitals in Taipei and healthy participants as control group for this study. Participants 100 patients with mTBI (35 men) who were older than 20 years, with a Glasgow Coma Scale score of 13–15 and loss of consciousness for <30 min, completed the baseline and 6-week follow-up assessments. 137 controls (47 men) without TBI were recruited in the study. None of the participants had a history of cerebrovascular disease, mental retardation, previous TBI, epilepsy or severe systemic medical illness. Primary outcome measures The Beck Anxiety Inventory (BAI), the Beck Depression Inventory II (BDI), the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI) were assessed for the patients with mTBI at baseline and 6 weeks after mTBI and for the controls. Results The ESS scores were not significantly different between the mTBI at baseline or at 6 weeks after mTBI and controls. Although the BAI, BDI and PSQI scores of the mTBI group were significantly different than those of the control group at baseline, all had improved significantly 6 weeks later. However, only the PSQI score improved to a level that was not significantly different from that of the control group. Conclusions Daytime sleepiness is not affected by mTBI. However, mTBI causes depression and anxiety and diminished sleep quality. Although all these conditions improve significantly within 6 weeks post-mTBI, only sleep quality improves to a pre-mTBI level. Thus, recovery from mTBI-induced sleep disturbance occurs more rapidly than that of mTBI-induced depression and anxiety.

Increased Long-Term Risk of Dementia in Patients With Carbon Monoxide Poisoning: A Population-Based Study.

Abstract Carbon monoxide (CO) poisoning may cause toxicity of the central nervous system and heart. However, the association between CO poisoning and long-term dementia risk remains unestablished. We investigated the incidence of dementia in patients with CO poisoning in Taiwan and evaluated whether they had a higher risk of dementia than did the general population. A nationwide population-based cohort study was conducted among patients with CO poisoning identified using Taiwans National Health Insurance Research Database (NHIRD) during 2004 to 2013. CO poisoning was defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification codes. The study cohort comprised patients with CO poisoning between 2005 and 2010 (N = 14,590). Each patient was age-, sex-, and index date-matched with 4 randomly selected controls from the comparison cohort (N = 58,360). All patients were followed from the study date until dementia development, death, or the end of 2013. Cox proportional hazards regressions were performed for comparing the hazard ratios for dementia between the 2 cohorts. Incident cases of dementia were identified from the NHIRD. After adjustment for potential confounders, the study cohort was independently associated with a higher dementia risk (adjusted hazard ratio, 2.75; 95% confidence interval, 2.26–3.35). This population-based cohort study indicated that patients with CO poisoning have a higher risk of dementia than do people without CO poisoning.

Balance function and sensory integration after mild traumatic brain injury

Abstract Objective: This study examined the disparities in balance functions and sensory integration in patients with mild traumatic brain injuries (mTBIs) and healthy controls. Participants: One hundred and seven patients with mTBI and 107 age- and sex-matched controls were recruaited for this study. Primary measures: Symptoms of dizziness, balance functions and the ability to perform daily activities were assessed using the dizziness handicap inventory (DHI). This study also performed the postural-stability test and a modified clinical test of sensory integration by using the Biodex Stability System (BBS). Results: DHI scores (functional, emotional, physical and total self-reported scores) were substantially increased in patients following an mTBI compared with the scores of the controls (p < 0.000). The postural-stability test indices (anterior-posterior) (p = 0.045) and the sensory-integration test index (eyes-open-firm-surface index) (p = 0.006) were substantially lower in patients with mTBI than in the controls. However, indices of two other postural-stability test indices (overall and medial-lateral) and three other sensory-integration tests indices (eyes-closed-firm-surface, eyes-open-foam-surface and eyes-closed-foam-surface) measured for the mTBI group did not differ from those of the control group. Conclusion: Activities of daily living, balance in postural stability and sensory integration were strongly impaired in patients with mTBI.

Predictions of the Length of Lumbar Puncture Needles

Introduction. The lumbar puncture is a well-known neurological procedure. The purpose of this study is to build an accurate mathematical formula to estimate the appropriate depth for inserting a lumbar puncture needle for a beginner. Methods. This is a retrospective study of patients who underwent magnetic resonance imaging (MRI) of the L-spine. The depth from the skin to the posterior and anterior margin of the spinal canal at the level of L4-L5 and L3-L4 interspaces of the spine was estimated using MRI. Results. Three hundred sixty-eight patients aged between 20 and 89 years were studied. The optimal puncture depths of the lumbar puncture needle were moderately strongly related to weight and BMI. The most accurate models with the highest coefficient of determination were 1.27 + 0.18 × BMI and 1.68 + 0.067 × weight (kg) for man and woman, respectively. Conclusion. The best formula for men and women provides the most accurate estimates for adults based on the MRI of the L-spine.