Platelet autophagic machinery involved in thrombosis through a novel linkage of AMPK-MTOR to sphingolipid metabolism.

Basal macroautophagy/autophagy has recently been found in anucleate platelets. Platelet autophagy is involved in platelet activation and thrombus formation. However, the mechanism underlying autophagy in anucleate platelets require further clarification. Our data revealed that LC3-II formation and SQSTM1/p62 degradation were noted in H2O2-activated human platelets, which could be blocked by 3-methyladenine and bafilomycin A1, indicating that platelet activation may cause platelet autophagy. AMPK phosphorylation and MTOR dephosphorylation were also detected, and block of AMPK activity by the AMPK inhibitor dorsomorphin reversed SQSTM1 degradation and LC3-II formation. Moreover, autophagosome formation was observed through transmission electron microscopy and deconvolution microscopy. These findings suggest that platelet autophagy was induced partly through the AMPK-MTOR pathway. In addition, increased LC3-II expression occurred only in H2O2-treated Atg5f/f platelets, but not in H2O2-treated atg5-/- platelets, suggesting that platelet autophagy occurs during platelet activation. atg5-/- platelets also exhibited a lower aggregation in response to agonists, and platelet-specific atg5-/- mice exhibited delayed thrombus formation in mesenteric microvessles and decreased mortality rate due to pulmonary thrombosis. Notably, metabolic analysis revealed that sphingolipid metabolism is involved in platelet activation, as evidenced by observed several altered metabolites, which could be reversed by dorsomorphin. Therefore, platelet autophagy and platelet activation are positively correlated, partly through the interconnected network of sphingolipid metabolism. In conclusion, this study for the first time demonstrated that AMPK-MTOR signaling could regulate platelet autophagy. A novel linkage between AMPK-MTOR and sphingolipid metabolism in anucleate platelet autophagy was also identified: platelet autophagy and platelet activation are positively correlated.Abbreviations: 3-MA: 3-methyladenine; A.C.D.: citric acid/sod. citrate/glucose; ADP: adenosine diphosphate; AKT: AKT serine/threonine kinase; AMPK: AMP-activated protein kinase; ANOVA: analysis of variance; ATG: autophagy-related; B4GALT/LacCS: beta-1,4-galactosyltransferase; Baf-A1: bafilomycin A1; BECN1: beclin 1; BHT: butylate hydrooxytoluene; BSA: bovine serum albumin; DAG: diacylglycerol; ECL: enhanced chemiluminescence; EDTA: ethylenediamine tetraacetic acid; ELISA: enzyme-linked immunosorbent assay; GALC/GCDase: galactosylceramidase; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GBA/GluSDase: glucosylceramidase beta; GPI: glycosylphosphatidylinositol; H2O2: hydrogen peroxide; HMDB: human metabolome database; HRP: horseradish peroxidase; IF: immunofluorescence; IgG: immunoglobulin G; KEGG: Kyoto Encyclopedia of Genes and Genomes; LAMP1: lysosomal associated membrane protein 1; LC-MS/MS: liquid chromatography-tandem mass spectrometry; mAb: monoclonal antibody; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MPV: mean platelet volume; MTOR: mechanistic target of rapamycin kinase; ox-LDL: oxidized low-density lipoprotein; pAb: polyclonal antibody; PC: phosphatidylcholine; PCR: polymerase chain reaction; PI3K: phosphoinositide 3-kinase; PLS-DA: partial least-squares discriminant analysis; PRP: platelet-rich plasma; Q-TOF: quadrupole-time of flight; RBC: red blood cell; ROS: reactive oxygen species; RPS6KB/p70S6K: ribosomal protein S6 kinase B; SDS: sodium dodecyl sulfate; S.E.M.: standard error of the mean; SEM: scanning electron microscopy; SGMS: sphingomyelin synthase; SM: sphingomyelin; SMPD/SMase: sphingomyelin phosphodiesterase; SQSTM1/p62: sequestosome 1; TEM: transmission electron microscopy; UGT8/CGT: UDP glycosyltransferase 8; UGCG/GCS: UDP-glucose ceramide glucosyltransferase; ULK1: unc-51 like autophagy activating kinase 1; UPLC: ultra-performance liquid chromatography; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; PtdIns3P: phosphatidylinositol-3-phosphate; WBC: white blood cell; WT: wild type.

Roles of sedative-hypnotics in patients with recurrent major depressive disorder: a nationwide population-based 14-year follow-up study in Taiwan.

BACKGROUND: The use of sedatives or hypnotics and the recurrence of depression have not been adequately explored. This study investigated the roles of sedative-hypnotics in patients with major depressive disorder (MDD). Various characteristics of sedative-hypnotic use were tested as risk factors for recurrence. METHODS: Clinical records of 15,510 patients with major depressive disorder who prescribed selective serotonin reuptake inhibitors (SSR) during 1997-2009 were collected from the National Health Insurance Research Database (NHIRD). Cox proportional hazard regression models were used to analyze factors related to depression recurrence. RESULTS: The risk of MDD recurrence was lower for patients using SED/HYP with an indication of both anxiolytics and hypnotics (AHR = 0.66; 95% CI = 0.59-0.72) than for those using SED/HYP with an indication of anxiolytics only. AHR was slightly greater in current users than in recent users (AHR = 0.77; 95% CI = 0.72-0.83) and past users (AHR = 0.70; 95% CI = 0.67-0.74). There was a higher AHR of MDD recurrence in patients who used SED/HYP over 1 DDD in 1 month than those who used SED/HYP less than 1 DDD in 1 month, with the highest-dose users having the highest risk of MDD recurrence (AHR = 7.91; 95% CI = 6.86-9.11). CONCLUSIONS: Patterns and characteristics of sedative-hypnotic use may affect depression recurrence. These findings should be considered by clinicians when combining sedative-hypnotics with antidepressant treatment.

Health care needs of elderly patients with lung, liver, or colon cancer in Taiwan.

BACKGROUND: Globally, different age groups in the elderly population have experienced major shifts over time. Human life expectancy doubled from the 19th to the twentieth century and has increased to 80 years in the twenty-first century. These conditions imply economic challenges and the increasing prevalence of certain health conditions. Old age is associated with increased care needs in various aspects of daily life. This study assessed the health care needs of elderly patients with lung, liver, and colorectal cancer in Taiwan and analyzed the factors underlying their needs. METHODS: This cross-sectional descriptive survey assessed 234 elderly patients with diagnosis of lung, liver, and colorectal cancer in Taiwan. We investigated their health care needs and daily living functions by using the Supportive Care Needs Survey and Karnofsky Performance Status, respectively. RESULTS: Patients required the most assistance in physical functioning and daily living. Patients aged ≥85 years required more care than those aged 65-74 years in terms of information access and sexuality needs. Patients with poor functional status required more care than those capable of undertaking normal activities. Patients diagnosed as having liver cancer required more care than those with lung or colorectal cancer. Patients with advanced cancer required more physical and daily care than those with early-stage cancer. CONCLUSIONS: Patients' health care needs differed with age, primary cancer site, and functional status. Patients aged ≥85 years and those with poor function, primary liver cancer, and advanced cancer had higher care needs.

Phospholipase D1 and D2 Synergistically Regulate Thrombus Formation.

Previously, we reported that phospholipase D1 (PLD1) and PLD2 inhibition by selective PLD1 and PLD2 inhibitors could prevent platelet aggregation in humans, but not in mice. Moreover, only the PLD1 inhibitor, but not PLD2 inhibitor, could effectively prevent thrombus formation in mice, indicating that PLD might play different roles in platelet function in humans and mice. Although PLD1 and PLD2 were reported to be implicated in thrombotic events, the role of PLD in mice remains not completely clear. Here, we investigated the role of PLD1 and PLD2 in acute pulmonary thrombosis and transient middle cerebral artery occlusion-induced brain injury in mice. The data revealed that inhibition of PLD1, but not of PLD2, could partially prevent pulmonary thrombosis-induced death. Moreover, concurrent PLD1 and PLD2 inhibition could considerably increase survival rate. Likewise, inhibition of PLD1, but not PLD2, partially improved ischemic stroke and concurrent inhibition of PLD1, and PLD2 exhibited a relatively better protection against ischemic stroke, as evidenced by the infarct size, brain edema, modified neurological severity score, rotarod test, and the open field test. In conclusion, PLD1 might play a more important role than PLD2, and both PLD1 and PLD2 could act synergistically or have partially redundant functions in regulating thrombosis-relevant events.

Carbon Dot Nanoparticles Exert Inhibitory Effects on Human Platelets and Reduce Mortality in Mice with Acute Pulmonary Thromboembolism.

The inhibition of platelet activation is considered a potential therapeutic strategy for the treatment of arterial thrombotic diseases; therefore, maintaining platelets in their inactive state has garnered much attention. In recent years, nanoparticles have emerged as important players in modern medicine, but potential interactions between them and platelets remain to be extensively investigated. Herein, we synthesized a new type of carbon dot (CDOT) nanoparticle and investigated its potential as a new antiplatelet agent. This nanoparticle exerted a potent inhibitory effect in collagen-stimulated human platelet aggregation. Further, it did not induce cytotoxic effects, as evidenced in a lactate dehydrogenase assay, and inhibited collagen-activated protein kinase C (PKC) activation and Akt (protein kinase B), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) phosphorylation. The bleeding time, a major side-effect of using antiplatelet agents, was unaffected in CDOT-treated mice. Moreover, our CDOT could reduce mortality in mice with ADP-induced acute pulmonary thromboembolism. Overall, CDOT is effective against platelet activation in vitro via reduction of the phospholipase C/PKC cascade, consequently suppressing the activation of MAPK. Accordingly, this study affords the validation that CDOT has the potential to serve as a therapeutic agent for the treatment of arterial thromboembolic disorders.

[Corrigendum] Structure­activity relationship of three synthesized benzimidazole­based oligosaccharides in human platelet activation.

Following the publication of the above paper, the authors noted that the third author affiliation was presented incorrectly. The third author affiliation should have been written as 'Department of Pharmacology, School of Medicine, College of Medicine, and Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110, Taiwan'. Therefore, the author and affiliation details for this paper should have been presented as follows (the changes are highlighted in bold): YI CHANg1­3*, WEN­HsIEN HsU2,4*, WEN­BIN YANg5, THANAsEKARAN JAYAKUMAR3, TZU­YIN LEE3, JOEN­RONg sHEU3, WAN­JUNg LU3,6 and JIUN­YI LI3,7. 1Department of Anesthesiology, Shin Kong Wu Ho­Su Memorial Hospital, Taipei 111; 2School of Medicine, Fu­Jen Catholic University, Xin Zhuang, New Taipei City 242; 3Department of Pharmacology, School of Medicine, College of Medicine, and Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei 110; 4Department of Surgery, Wan­Fang Hospital, Taipei Medical University, Taipei 116; 5Genomics Research Center, Academia Sinica, Taipei 115; 6Department of Medical Research and Translational Laboratory, Research Department, Taipei Medical University Hospital, Taipei 110; 7Department of Cardiovascular Surgery, Mackay Memorial Hospital, and Mackay Medical College, Taipei 104, Taiwan, R.O.C.. The authors regret that the error with the third author affiliation was not noticed prior to the publication of their paper, and apologize for any inconvenience caused. [The original article was published in International Journal of Molecular Medicine 40: 1520­1528, 2017; DOI: 10.3892/ijmm.2017.3133].

VAS2870 and VAS3947 attenuate platelet activation and thrombus formation via a NOX-independent pathway downstream of PKC.

NADPH oxidase (NOX) enzymes are involved in a various physiological and pathological processes such as platelet activation and inflammation. Interestingly, we found that the pan-NOX inhibitors VAS compounds (VAS2870 and its analog VAS3947) exerted a highly potent antiplatelet effect. Unlike VAS compounds, concurrent inhibition of NOX1, 2, and 4 by treatment with ML171, GSK2795039, and GKT136901/GKT137831 did not affect thrombin and U46619-induced platelet aggregation. These findings suggest that VAS compounds may inhibit platelet aggregation via a NOX-independent manner. Thus, we aimed to investigate the detailed antiplatelet mechanisms of VAS compounds. The data revealed that VAS compounds blocked various agonist-induced platelet aggregation, possibly via blocking PKC downstream signaling, including IKKß and p38 MAPK, eventually reducing platelet granule release, calcium mobilization, and GPIIbIIIa activation. In addition, VAS compounds inhibited mouse platelet aggregation-induced by collagen and thrombin. The in vivo study also showed that VAS compounds delayed thrombus formation without affecting normal hemostasis. This study is the first to demonstrate that, in addition to inhibiting NOX activity, VAS compounds reduced platelet activation and thrombus formation through a NOX-independent pathway downstream of PKC. These findings also indicate that VAS compounds may be safe and potentially therapeutic agents for treating patients with cardiovascular diseases.

Embelin as a Novel Inhibitor of PKC in the Prevention of Platelet Activation and Thrombus Formation.

Embelin is a quinone derivative and found in the fruits of Embelia ribes Burm.f. Embelin has been identified as a small molecular inhibitor of X-chromosome-linked inhibitor of apoptosis proteins, and has multiple biological activities, including antioxidation, anti-inflammation, and antitumor effects. However, the effect of embelin in platelets remains unclear. Thus, this study investigated the antiplatelet mechanism of embelin. Our data revealed that embelin could inhibit platelet aggregation induced by various agonists, including the protein kinase C (PKC) activator phorbol 12,13-dibutyrate (PDBu). Embelin, as well as the PKC inhibitor Ro 31-8220, markedly reduced PDBu-mediated phosphorylation of the PKC substrate, suggesting that embelin may be a PKC inhibitor for platelets. Embelin could block PKC downstream signaling and events, including the inhibition of protein kinase B and mitogen-activated protein kinase activation, granule release, and glycoprotein IIbIIIa activation. Moreover, embelin could delay thrombus formation in the mesenteric microvessels of mice, but did not significantly affect the tail bleeding time. In conclusion, we demonstrated that embelin is a PKC inhibitor and possesses antiplatelet and antithrombotic effects. The further analysis is necessary to more accurately determine clinical therapeutic potential of embelin in all clinical thromboembolic events with disturbance of thrombocyte function.

Association between Sedative-hypnotics and Subsequent Cancer in Patients with and without Insomnia: A 14-year Follow-up Study in Taiwan.

Background: The aim of this population-based 14-year historical and prospective study was to determine the relationships between the usage of sedative-hypnotics, including benzodiazepines and nonbenzodiazepines, and the risk of subsequent cancer in patients with or without insomnia among the Taiwanese population. Methods: A total of 43,585 patients were recruited, 21,330 of whom had been diagnosed with insomnia and 8,717 who had been prescribed sedative-hypnotics during this study's following period of 2002 to 2015. Information from the claims data, namely basic demographic details, drug prescriptions, comorbidities, and patients' survival, was extracted from the National Health Insurance Research Database for χ2 analysis. A Cox proportional hazards model was used to compute the 14-year cancer-free survival rates after adjustment for confounding factors. Results: Patients with insomnia who used sedative-hypnotics had an adjusted hazard ratio of 1.49 compared with patients with insomnia who did not use any sedative-hypnotics, and patients without insomnia who used sedative-hypnotics had an adjusted hazard ratio of 1.68 compared with patients without insomnia who did not use any sedative-hypnotics. Regarding site-specific risk, patients with insomnia who used sedative-hypnotics had an increased risk of oral and breast cancers, and patients without insomnia who received sedative-hypnotics prescriptions had an increased risk of liver and breast cancers. The cancer-free survival rate of patients who had used sedative-hypnotics was significantly lower than that of patients who had never used sedative-hypnotics. Conclusions: The use of sedative-hypnotics in patients either with or without insomnia was associated with subsequent cancer development in the Taiwanese population. Increased risks of oral, liver, and breast cancer were found in the patients with the use of sedative-hypnotics. The use of sedative-hypnotics should be discouraged for treating patients with or without insomnia in Taiwan.

Esculetin, a Coumarin Derivative, Prevents Thrombosis: Inhibitory Signaling on PLCγ2-PKC-AKT Activation in Human Platelets.

Esculetin, a bioactive 6,7-dihydroxy derivative of coumarin, possesses pharmacological activities against obesity, diabetes, renal failure, and cardiovascular disorders (CVDs). Platelet activation plays a major role in CVDs. Thus, disrupting platelet activation represents an attractive therapeutic target. We examined the effect of esculetin in human platelet activation and experimental mouse models. At 10-80 µM, esculetin inhibited collagen- and arachidonic acid-induced platelet aggregation in washed human platelets. However, it had no effects on other agonists such as thrombin and U46619. Esculetin inhibited adenosine triphosphate release, P-selectin expression, hydroxyl radical (OH·) formation, Akt activation, and phospholipase C (PLC)γ2/protein kinase C (PKC) phosphorylation, but did not diminish mitogen-activated protein kinase phosphorylation in collagen-activated human platelets. Platelet function analysis indicated that esculetin substantially prolonged the closure time of whole blood. In experimental mice, esculetin significantly increased the occlusion time in thrombotic platelet plug formation and reduced mortality associated with acute pulmonary thromboembolism. However, it did not prolong the bleeding time. This study demonstrates that esculetin inhibits human platelet activation via hindering the PLCγ2-PKC cascade, hydroxyl radical formation, Akt activation, and ultimately suppressing platelet activation. Therefore, esculetin may act as an essential therapeutic agent for preventing thromboembolic diseases.

Mental disorders and medical comorbidities: Association rule mining approach.

PURPOSE: This study explored the medical comorbidities of mental disorders using association rule mining. DESIGN AND METHODS: Patients diagnosed with mental disorders between 2002 and 2010 were identified. An equal number of nonmental disorder subjects were randomly selected and matched with case group by age and gender. FINDINGS: Sleep disorders and digestive diseases were frequent comorbidities among mental disorders. The specific medical comorbidities were diabetes mellitus, chronic liver disease, extrapyramidal diseases, disorders of stomach function, general symptoms, sleep disturbance, and family circumstances. PRACTICE IMPLICATIONS: The results suggest that education of professional knowledge of comorbid conditions should be provided to nurses for caring patients with mental illnesses.

Hinokitiol Inhibits Migration of A549 Lung Cancer Cells via Suppression of MMPs and Induction of Antioxidant Enzymes and Apoptosis.

Hinokitiol, a natural monoterpenoid from the heartwood of Calocedrus formosana, has been reported to have anticancer effects against various cancer cell lines. However, the detailed molecular mechanisms and the inhibiting roles of hinokitiol on adenocarcinoma A549 cells remain to be fully elucidated. Thus, the current study was designed to evaluate the effect of hinokitiol on the migration of human lung adenocarcinoma A549 cells in vitro. The data demonstrates that hinokitiol does not effectively inhibit the viability of A549 cells at up to a 10 µM concentration. When treated with non-toxic doses (1-5 µM) of hinokitiol, the cell migration is markedly suppressed at 5 µM. Hinokitiol significantly reduced p53 expression, followed by attenuation of Bax in A549 cells. A dose-dependent inhibition of activated caspase-9 and -3 was observed in the presence of hinokitiol. An observed increase in protein expression of matrix metalloproteinases (MMPs) -2/-9 in A549 cells was significantly inhibited by hinokitiol. Remarkably, when A549 cells were subjected to hinokitiol (1-5 µM), there was an increase in the activities of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) from the reduction in cells. In addition, the incubation of A549 cells with hinokitiol significantly activated the cytochrome c expression, which may be triggered by activation of caspase-9 followed by caspase-3. These observations indicate that hinokitiol inhibited the migration of lung cancer A549 cells through several mechanisms, including the activation of caspases-9 and -3, induction of p53/Bax and antioxidant CAT and SOD, and reduction of MMP-2 and -9 activities. It also induces cytochrome c expression. These findings demonstrate a new therapeutic potential for hinokitiol in lung cancer chemoprevention.

Nocturnal sleep mediates the relationship between morningness-eveningness preference and the sleep architecture of afternoon naps in university students.

The present study investigated the parameters of nocturnal sleep that mediate the relationship between morningness-eveningness preference and the sleep architecture of naps in university students. This study had a cross-sectional, descriptive correlational design. The sleep architecture of 52 students invited to take an afternoon nap in the laboratory was recorded. The morningness-eveningness questionnaire (MEQ) was used to evaluate morningness-eveningness preference. An actigraph was used to collect students' nighttime sleep data in the week preceding the study. Polysomnography was used to measure the sleep architecture of the participants' naps. After adjustments for potential factors, although the MEQ did not directly correlate with the percentage of sleep stages in naps, the effects of the MEQ on the percentage of Stage 1 sleep, slow-wave sleep, and rapid eye movement sleep; sleep duration; and sleep efficiency of naps were mediated by the total sleep time in the preceding week. This preliminary study suggests that nap quality was affected by morningness-eveningness preference through the mediation of total nocturnal sleep time. Therefore, future studies should be carefully designed to consider nighttime sleep patterns when analyzing the effects of chronotypes on daytime sleep.

Structure-activity relationship of three synthesized benzimidazole-based oligosaccharides in human platelet activation.

Antiplatelet agents have considerable benefits in the treatment of thromboembolic diseases; however, these agents still have substantial limitations due to their severe side-effects. In this study, the antiplatelet activity of three newly synthesized saccharide based benzimidazole derivatives, M3BIM, Malto-BIM and Melibio-BIM, in collagen and thrombin-stimulated human platelets in vitro was examined. Among the compounds tested, only compound M3BIM exerted concentration (20-60 µM)-dependent inhibitory effects against collagen (1 µg/ml) and thrombin (0.01 U/ml)-induced washed human platelet aggregation. Moreover, at a concentration of 60 µM, M3BIM distinctly abolished collagen-induced adenosine triphosphate (ATP) release and intracellular Ca2+ mobilization. Additionally, this compound attenuated the collagen-induced phosphorylation of p47, a marker of the activation of protein kinase C (PKC) and p38 mitogen-activated protein kinase (MAPK). However, Malto-BIM and Melibio-BIM were not effective in this regard. Moreover, the toxic effects of these compounds were evaluated using zebrafish embryo toxicity (ZET) assay, and the results revealed that all three compounds had no comparative cytotoxicity within the range of 25-200 µM. Overall, the results of this study provide evidence for the inhibitory effects of M3BIM on collagen-induced platelet aggregation in vitro compared to other imidazole derivatives. The presence of 1-imidazolyl moiety at one end with a longer chain length (three sugar moieties) may be mainly responsible for the observed effects of M3BIM. These results suggest that compound M3BIM may be used as a potential candidate for the treatment of aberrant platelet activation-related diseases as it inhibits the activation of p47 and p38 MAPK, and reduces ATP release and Ca2+ mobilization.

Development of Benzimidazole Derivatives as Novel Anti-platelet Drugs.

BACKGROUND: Benzimidazoles are privileged biomolecules which form an integral part of vitamin B12 and have been attracting numerous researchers all over the world to assess their potential therapeutic significance. OBJECTIVES: The comparative in vitro antiplatelet activity of newly synthesized benzimidazole derivatives, M3BIM, C2BIM, and L2BIM in thrombin, adenosine diphosphate (ADP) and epinephrineinduced washed human platelets was investigated. METHOD: Reversed-phase silica gel column chromatography, Aggregometry, Flow cytometry and Immunoblotting were used in this study. RESULTS: M3BIM exhibited a concentration (25-100 µM) dependent inhibitory effect on platelet aggregation induced by thrombin (0.01 U/mL) in washed human platelets and by epinephrine (10 µM) only at a maximum concentration of 500 µM in platelet-rich plasma (PRP); however, C2BIM and L2BIM had no response even at 500 µM against thrombin and 1mM against epinephrine-induced platelet aggregation. Moreover, all these three compounds were not inhibited platelet aggregation induced by ADP (20 µM). Additionally, these compounds showed no effects in thrombin-induced P-selectin expression and αIIbß3 activation, as evidenced by flow cytometry and clot reaction assays, respectively. Besides, M3BIM (100 µM) significantly abolished thrombin-induced Akt and mitogen-activated protein kinases (MAPKs) phosphorylation; whereas 200 µM C2BIM and L2BIM were not effective on these proteins. CONCLUSION: This study affords confirmation for the inhibitory effect of M3BIM in a low dose thrombin and epinephrine-induced platelet aggregation in vitro compared to other imidazole derivatives, C2BIM and L2BIM. These outcomes may recommend that M3BIM can be appraised as a prospective benzeimidazole compound for the treatment of thrombin -induced platelet defect and its related diseases.

Honokiol as a specific collagen receptor glycoprotein VI antagonist on human platelets: Functional ex vivo and in vivo studies.

Honokiol, derived from Magnolia officinalis, has various pharmacological properties. Platelet activation plays a critical role in cardiovascular diseases. Honokiol has been reported to inhibit collagen-stimulated rabbit platelet aggregation. However, detailed further studies on the characteristics and functional activity of honokiol in platelet activation are relatively lacking. In the present study, honokiol specifically inhibited platelet aggregation and Ca+2 ion mobilization stimulated with collagen or convulxin, an agonist of glycoprotein (GP) VI, but not with aggretin, an agonist of integrin α2ß1. Honokiol also attenuated the phosphorylation of Lyn, PLCγ2, PKC, MAPKs, and Akt after convulxin stimulation. Honokiol have no cytotoxicity in zebrafish embryos. Honokiol diminished the binding of anti-GP VI (FITC-JAQ1) mAb to human platelets, and it also reduced the coimmunoprecipitation of GP VI-bound Lyn after convulxin stimulation. The surface plasmon resonance results revealed that honokiol binds directly to GP VI, with a KD of 289 µM. Platelet function analysis revealed that honokiol substantially prolonged the closure time in human whole blood and increased the occlusion time of thrombotic platelet plug formation in mice. In conclusion, honokiol acts as a potent antagonist of collagen GP VI in human platelets, and it has therapeutic potential in the prevention of the pathological thrombosis.

Insomnia in female nurses: a nationwide retrospective study.

OBJECTIVE: This study explored the incidence of insomnia in female nursing staff and compared the incidence with that in other medical and nonmedical female workers. METHODS: This retrospective study analyzed female nurses with insomnia using data from January 1, 2004 to December 31, 2008. The incidence of insomnia in other female medical workers and nonmedical female workers was also analyzed and compared with that of the nurses. Using the Taiwan National Health Insurance Research Database, each study patient was identified by ID number. The incidence and rate ratio of insomnia were calculated according to their outpatient claims. RESULTS: Compared with other medical and nonmedical female workers, female nurses had higher incidences of adjustment insomnia and psychophysiological insomnia. However, female nurses had a lower incidence of nonorganic insomnia than did other female medical personnel. Older participants and those with the comorbidities of depressive and respiratory disorders had a higher risk of insomnia than did younger participants and those with other comorbidities. CONCLUSION: We suggest that nurses should be encouraged to relax in order to facilitate stress relief and improve their quality of sleep.

Effect of Antrodia camphorata on inflammatory arterial thrombosis-mediated platelet activation: the pivotal role of protein kinase C.

Antrodia camphorata is a rare Taiwanese medicinal mushroom. Antrodia camphorata extract has been reported to exhibit antioxidant, anti-inflammation, antimetastasis, and anticancer activities and plays a role in liver fibrosis, vasorelaxation, and immunomodulation. Critical vascular inflammation leads to vascular dysfunction and cardiovascular diseases, including abdominal aortic aneurysms, hypertension, and atherosclerosis. Platelet activation plays a crucial role in intravascular thrombosis, which is involved in a wide variety of cardiovascular diseases. However, the effect of Antrodia camphorata on platelet activation remains unclear. We examined the effects of Antrodia camphorata on platelet activation. In the present study, Antrodia camphorata treatment (56-224 µg/mL) inhibited platelet aggregation induced by collagen, but not U46619, an analogue of thromboxane A2, thrombin, and arachidonic acid. Antrodia camphorata inhibited collagen-induced calcium (Ca(2+)) mobilization and phosphorylation of protein kinase C (PKC) and Akt. In addition, Antrodia camphorata significantly reduced the aggregation and phosphorylation of PKC in phorbol-12, 13-dibutyrate (PDBu) activated platelets. In conclusion, Antrodia camphorata may inhibit platelet activation by inhibiting of Ca(2+) and PKC cascade and the Akt pathway. Our study suggests that Antrodia camphorata may be a potential therapeutic agent for preventing or treating thromboembolic disorders.

Amarogentin, a secoiridoid glycoside, abrogates platelet activation through PLC γ 2-PKC and MAPK pathways.

Amarogentin, an active principle of Gentiana lutea, possess antitumorigenic, antidiabetic, and antioxidative properties. Activation of platelets is associated with intravascular thrombosis and cardiovascular diseases. The present study examined the effects of amarogentin on platelet activation. Amarogentin treatment (15~60 µM) inhibited platelet aggregation induced by collagen, but not thrombin, arachidonic acid, and U46619. Amarogentin inhibited collagen-induced phosphorylation of phospholipase C (PLC) γ2, protein kinase C (PKC), and mitogen-activated protein kinases (MAPKs). It also inhibits in vivo thrombus formation in mice. In addition, neither the guanylate cyclase inhibitor ODQ nor the adenylate cyclase inhibitor SQ22536 affected the amarogentin-mediated inhibition of platelet aggregation, which suggests that amarogentin does not regulate the levels of cyclic AMP and cyclic GMP. In conclusion, amarogentin prevents platelet activation through the inhibition of PLC γ2-PKC cascade and MAPK pathway. Our findings suggest that amarogentin may offer therapeutic potential for preventing or treating thromboembolic disorders.