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1.
Biochem Biophys Res Commun ; 464(3): 698-704, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26168721

RESUMO

Cellular heparan sulfate (HS) has a dual role in scrapie pathogenesis; it is required for PrP(Sc) (scrapie prion protein) formation and facilitates infection of cells, mediating cellular uptake of prions. We examined the involvement of heparanase, a mammalian endoglycosidase degrading HS, in scrapie infection. In cultured cells, heparanase treatment or over-expression resulted in a profound decrease in PrP(Sc). Moreover, disease onset and progression were dramatically delayed in scrapie infected transgenic mice over-expressing heparanase. Together, our results provide direct in vivo evidence for the involvement of intact HS in the pathogenesis of prion disease and the protective role of heparanase both in terms of susceptibility to infection and disease progression.


Assuntos
Glucuronidase/genética , Glucuronidase/metabolismo , Doenças Priônicas/prevenção & controle , Animais , Linhagem Celular , Cricetinae , Progressão da Doença , Suscetibilidade a Doenças , Feminino , Heparitina Sulfato/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas PrPSc/metabolismo , Proteínas PrPSc/patogenicidade , Doenças Priônicas/etiologia , Doenças Priônicas/metabolismo , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Scrapie/etiologia , Scrapie/metabolismo , Scrapie/prevenção & controle , Fatores de Tempo , Regulação para Cima
2.
Lipids Health Dis ; 14: 142, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26537218

RESUMO

BACKGROUND: Bioavailability of krill oil has been suggested to be higher than fish oil as much of the EPA and DHA in krill oil are bound to phospholipids (PL). Hence, PL content in krill oil might play an important role in incorporation of n-3 PUFA into the RBC, conferring properties that render it effective in reducing cardiovascular disease (CVD) risk. The objective of the present trial was to test the effect of different amounts of PL in krill oil on the bioavailability of EPA and DHA, assessed as the rate of increase of n-3 PUFA in plasma and RBC, in healthy volunteers. METHODS AND DESIGN: In a semi randomized crossover single blind design study, 20 healthy participants consumed various oils consisting of 1.5 g/day of low PL krill oil (LPL), 3 g/day of high PL krill oil (HPL) or 3 g/day of a placebo, corn oil, for 4 weeks each separated by 8 week washout periods. Both LPL and HPL delivered 600 mg of total n-3 PUFA/day along with 600 and 1200 mg/day of PL, respectively. RESULTS: Changes in plasma EPA, DPA, DHA, total n-3 PUFA, n-6:n-3 ratio and EPA + DHA concentrations between LPL and HPL krill oil supplementations were observed to be similar. Intake of both forms of krill oils increased the RBC level of EPA (p < 0.001) along with reduced n-6 PUFA (LPL: p < 0.001: HPL: p = 0.007) compared to control. HPL consumption increased (p < 0.001) RBC concentrations of EPA, DPA, total and n-3 PUFA compared with LPL. Furthermore, although LPL did not alter RBC n-6:n-3 ratio or the sum of EPA and DHA compared to control, HPL intake decreased (p < 0.001) n-6:n-3 ratio relative to control with elevated (p < 0.001) sum of EPA and DHA compared to control as well as to LPL krill oil consumption. HPL krill oil intake elevated (p < 0.005) plasma total and LDL cholesterol concentrations compared to control, while LPL krill oil did not alter total and LDL cholesterol, relative to control. CONCLUSIONS: The results indicate that krill oil with higher PL levels could lead to enhanced bioavailability of n-3 PUFA compared to krill oil with lower PL levels. TRIAL REGISTRATION: Clinicaltrials.gov# NCT01323036.


Assuntos
Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Eritrócitos/metabolismo , Fosfolipídeos/metabolismo , Adolescente , Adulto , Animais , Estudos Cross-Over , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/farmacocinética , Ácido Eicosapentaenoico/farmacocinética , Euphausiacea/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Cureus ; 16(8): e66234, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39238692

RESUMO

Introduction The human immunodeficiency virus (HIV) primarily targets clusters of differentiation 4 (CD4)+ T cells and other immune cells, leading to immune dysfunction. Cytokines such as interleukin (IL)-23 and IL-27 have complex roles in HIV-associated disease progression, affecting viral replication and immune responses. This study aimed to explore the correlation between HIV-related CD4 lymphopenia and the inflammatory cytokines IL-23 and IL-27 in treatment-naive HIV patients.  Materials and methods This is a single-center, prospective, observational study conducted at the Antiretroviral Treatment (ART) Center of Jawaharlal Nehru Medical College and Hospital, Aligarh Muslim University, Aligarh, Uttar Pradesh, India. Sixty-five treatment-naive HIV seropositive patients were recruited in this study. Quantitative estimation of inflammatory biomarkers (IL-23 and IL-27) was performed using enzyme-linked immunosorbent assay (ELISA). The fluorescent-activated cell sorter count (FACSCount) technology was used to determine the CD4+ T-cell count.  Results Our study revealed that HIV-infected individuals had significantly higher levels of IL-23 (868.9±246.7 pg/mL vs 98.3±86.6 pg/mL, p < 0.01) and IL-27 (1629.5±518.5 pg/mL vs 291.3±225.2 pg/mL, p < 0.01) compared to healthy controls. Additionally, we found a strong positive correlation between CD4 count and IL-23 titers (r = 0.93, p < 0.01), as well as between CD4 count and IL-27 titers (r = 0.92, p < 0.01) in HIV-positive individuals.  Conclusion The findings suggest that these cytokines respond to HIV infection and may potentially play a crucial role in restraining HIV replication and slowing down the progression of the disease.

4.
Pediatr Hematol Oncol ; 26(4): 157-64, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19437318

RESUMO

INTRODUCTION: The aim of this pilot study was to determine heparanase plasma levels (HP) at diagnosis and at restaging in children diagnosed with Hodgkin lymphoma and to investigate whether this parameter provides prognostic information for response to treatment after induction therapy. PATIENTS AND METHODS: HP levels of 19 pediatric patients (mean age: 10.3 years (y) (range, 4-18 y), 9 girls, 10 boys) with Hodgkin lymphoma were assayed at diagnosis and at restaging. HP levels were determined using an ELISA anti-human heparanase immunoassay kit. According to diagnosis, CAT scan and/or FDG/ PET-CT fusion were performed to assess response to treatment after 2-3 courses of chemotherapy. Two patients received VAMP protocol (1 stage IA, 1 stage IIA), 1 received AV-PC (nonbulky stage IIA), 4 received COPP/ABV (3 stage IIA bulky, 1 stage IIIA nonbulky), 4 received ABVE-PC (2 stage IIB, 1 stage IIA bulky, 1 stage IIIA bulky), 2 received ABVD (1 stage IIA bulky, 1 stage IIIA), and 6 received escalated BEACOPP (1 stage IIIB, 3 stage IVA, 2 stage IVB). RESULTS: Changes in HP levels were found to correlate with response to treatment for most of the children. At diagnosis, average HP level was 1019 pg/mL (range, 141-5733 pg/mL), decreasing at restaging to 588 pg/mL (range, 62-3267 pg/mL) (p = .034). At diagnosis, the average HP of the 16 patients in CR or VGPR was 1104 pg/mL; it had decreased at restaging to 586 pg/mL (p = .032). At diagnosis, the average HP level for the 3 patients with TP or PR was 1704 pg/mL; it had increased to 1938 pg/mL at restaging (p = .166). Due to the small number of patients, no correlation was observed between HP levels at diagnosis, staging, or any other clinical prognostic factor. CONCLUSIONS: Changes in plasma HP levels correlated with response to treatment for children diagnosed with Hodgkin lymphoma. This provides a rationale for exploring clinical interest in plasma heparanase measurements of a larger group, using the test for clinical trials of antiangiogenic therapies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/sangue , Glucuronidase/sangue , Doença de Hodgkin/sangue , Doença de Hodgkin/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Doença de Hodgkin/tratamento farmacológico , Humanos , Masculino , Estadiamento de Neoplasias , Projetos Piloto
5.
J Thromb Haemost ; 4(11): 2443-51, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16970801

RESUMO

BACKGROUND: Over-expression of tissue factor (TF) and activation of the coagulation system are common in cancer patients. Heparanase is an endo-beta-D-glucuronidase that cleaves heparan sulfate chains on cell surfaces and in the extracellular matrix, activity that closely correlates with cell invasion, angiogenesis and tumor metastasis. The study was undertaken to investigate the involvement of heparanase in TF expression. METHODS: Tumor-derived cell lines were transfected with heparanase cDNA and TF expression was examined. The effect of exogenous addition of active and inactive heparanase on TF expression and activity was studied in tumor cell lines and primary human umbilical vein endothelial cells. TF expression was also explored in heparanase over-expressing transgenic (Tg) mice. Blast cells were collected from acute leukemia patients and TF and heparanase expression levels were analyzed. RESULTS: Over-expression of heparanase in tumor-derived cell lines resulted in a 2-fold increase in TF expression levels, and a similar trend was observed in heparanase Tg mice in vivo. Likewise, exogenous addition of heparanase to endothelial or tumor-derived cells resulted in enhanced TF expression and activity. Interestingly, TF expression was also induced in response to enzymatically inactive heparanase, suggesting that this effect was independent of heparanase enzymatic activity. The regulatory effect of heparanase on TF expression involved activation of the p38 signaling pathway. A positive correlation between TF expression levels and heparanase activity was found in blasts collected from 22 acute leukemia patients. CONCLUSIONS: Our results indicate that in addition to its well-known function as an enzyme paving a way for invading cells, heparanase also participates in the regulation of TF gene expression and its related coagulation pathways.


Assuntos
Células Endoteliais/metabolismo , Regulação Leucêmica da Expressão Gênica , Heparina Liase/biossíntese , Leucemia Mieloide Aguda/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Tromboplastina/biossíntese , Coagulação Sanguínea/genética , Linhagem Celular Tumoral , Células Endoteliais/patologia , Regulação Leucêmica da Expressão Gênica/genética , Heparina Liase/genética , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Invasividade Neoplásica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia
6.
Thromb Res ; 134(3): 639-42, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25065557

RESUMO

BACKGROUND: Heparanase is implicated in angiogenesis and tumor progression. We had earlier demonstrated that heparanase may also affect the hemostatic system in a non-enzymatic manner. It forms a complex and enhances the activity of the blood coagulation initiator- tissue factor (TF). Although increased heparanase antigen level in the plasma and biopsies of cancer patients was previously demonstrated, in the present study we evaluated, for the first time, the heparanase procoagulant activity in the plasma of patients with lung cancer. MATERIALS AND METHODS: Sixty five patients with non-small cell lung cancer at presentation and twenty controls were recruited. Plasma was studied for TF / heparanase procoagulant activity, TF activity and heparanase procoagulant activity using chromogenic assay and heparanase antigen levels by ELISA. RESULTS: Heparanase antigen levels were higher in the study group compared to control (P=0.05). TF / heparanase activity, and even more apparent, heparanase procoagulant activity were significantly higher in the study group compared to controls (P=0.008, P<0.0001, respectively). No significant difference was observed in the TF activity between the groups. Survival of patients with heparanase procoagulant activity higher than 31 ng/ml predicted a mean survival of 9 ± 1.3 months while heparanase procoagulant activity of 31 ng/ml or lower predicted a mean survival of 24 ± 4 months (P=0.001). Heparanase procoagulant activity was higher than 31 ng/ml in the four cases of thrombosis detected during the follow-up period. CONCLUSIONS: Elevated heparanase procoagulant activity in patients with lung cancer reveals a new mechanism of coagulation system activation in malignancy. Heparanase procoagulant activity can potentially be used as a predictor for survival.


Assuntos
Biomarcadores Tumorais/sangue , Coagulação Sanguínea , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Glucuronidase/sangue , Neoplasias Pulmonares/enzimologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Estudos de Casos e Controles , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Trombose/sangue , Trombose/enzimologia , Trombose/etiologia , Fatores de Tempo , Regulação para Cima
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