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3.
Cancer Sci ; 113(5): 1752-1762, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35243724

RESUMO

We investigated the anticancer effect of the aptamer-conjugated gemcitabine-loaded atelocollagen patch in a pancreatic cancer patient-derived xenograft (PDX) model to propose a future potential adjuvant surgical strategy during curative pancreatic resection for pancreatic cancer. A pancreatic cancer PDX model was established. Animals were grouped randomly into a no-treatment control group; treatment group treated with intraperitoneal gemcitabine injection (IP-GEM) or aptamer-conjugated gemcitabine (APT:GEM); and transplant with three kinds of patches: atelocollagen-aptamer-gemcitabine (patch I), atelocollagen-inactive aptamer-gemcitabine (patch II), and atelocollagen-gemcitabine (patch III). Tumor volumes and response were evaluated based on histological analysis by H&E staining and Immunohistochemistry (IHC) was performed. Anticancer therapy-related toxicity was evaluated by hematologic findings. The patch I group showed the most significant reduction of tumor growth rate, compared with the no-treatment group (p < 0.05). However, other treatment groups were not found to show significant reduction in tumor growth rate (0.05 < p < 0.1). There was no microscopic evidence suggesting potential toxicity, such as inflammation, nor necrotic changes in liver, lung, kidney, and spleen tissue. In addition, no leukopenia, anemia, or neutropenia was observed in the patch I group. This implantable aptamer-drug conjugate system is thought to be a new surgical strategy to augment the oncologic significance of margin-negative resection in treating pancreatic cancer in near future.


Assuntos
Neoplasias Pancreáticas , Animais , Humanos , Linhagem Celular Tumoral , Colágeno , Desoxicitidina/análogos & derivados , Modelos Animais de Doenças , Gencitabina , Xenoenxertos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias Pancreáticas
4.
J Clin Apher ; 36(1): 135-142, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33247855

RESUMO

BACKGROUND: Peripheral blood stem cell (PBSC) collection is important for successful hematopoietic stem cell transplantation. This study aimed to investigate the laboratory parameters associated with the optimal timing of autologous PBSC collection from lymphoma and multiple myeloma patients. METHODS: We retrospectively evaluated data from 1105 PBSC apheresis procedures performed on 379 adult patients at the National Cancer Center between June 2005 and December 2019. Laboratory parameters, including cutoff values for the number of hematopoietic progenitor cells (HPCs) and circulating CD34+ cells, were analyzed to determine their association with CD34+ cell yield. RESULTS: The pre-apheresis HPC and CD34+ cell count were statistically significant variables associated with harvested CD34+ cell in lymphoma and MM patients. The optimal cutoff values were 18 × 106 /L for pre-HPC count (66.8% sensitivity, 66.4% specificity) and 11/µL for pre-CD34+ cell count (85.8% sensitivity, 87.2% specificity), to achieve CD34+ cell yields ≥ 1.0 × 106 /kg for each apheresis procedure. Moreover, the optimal cutoff values were 23 × 106 /L for pre-HPC count (71.0% sensitivity, 69.0% specificity) and 18/µL for pre-CD34+ cell count (87.5% sensitivity, 86.3% specificity) to achieve CD34+ cell yields ≥ 2.0 × 106 /kg for each apheresis procedure. CONCLUSION: HPC count is a potential surrogate marker for monitoring the starting time for PBSC collection. Applying cutoff values for the number of HPC and CD34+ cells may be clinically useful for optimizing the timing of PBSC collection.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Mobilização de Células-Tronco Hematopoéticas/métodos , Linfoma/terapia , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Estudos Retrospectivos , Transplante Autólogo , Adulto Jovem
5.
J Clin Apher ; 36(1): 28-33, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32882095

RESUMO

INTRODUCTION: Autologous peripheral blood stem cell (PBSC) transplantation has become a standard treatment option for many oncology patients. The aim of this study was to evaluate the performance of two cell separators, Spectra Optia (Terumo BCT, Japan) and Amicus (Fresenius-Kabi) for autologous PBSC collection. METHODS: We retrospectively evaluated 56 apheresis by Spectra Optia with Continuous Mononuclear Cell Collection (cMNC) from 20 patients, and 50 apheresis by Amicus from 27 patients between December 2018 and December 2019. CD34+ collection efficiency (CE2) and platelet (PLT) loss were evaluated. RESULTS: There was no significant difference in CD34+ CE2 between Spectra Optia with cMNC (median, 28.8%) and Amicus (median, 33.1%; P = 0.537). PLT loss was significantly lower in Amicus (median, 28.6%) than in Spectra Optia with cMNC (median, 37.8%; P = 0.009). CONCLUSION: CD34+ CE2 was comparable between Spectra Optia and Amicus, and PLT loss was significantly lower in Amicus. To the best of our knowledge, this is the first report comparing autologous PBSC collection of the Spectra Optia and Amicus. These results may provide general guidance with regard to device selection to apheresis clinics that use both separators for optimal outcomes depending on each patient's characteristics.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Mobilização de Células-Tronco Hematopoéticas/métodos , Células-Tronco de Sangue Periférico/citologia , Adulto , Remoção de Componentes Sanguíneos/instrumentação , Feminino , Mobilização de Células-Tronco Hematopoéticas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo , Adulto Jovem
6.
Comput Methods Programs Biomed ; 195: 105662, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32712504

RESUMO

BACKGROUND AND OBJECTIVE: The dielectrophoresis (DEP) technique is increasingly being recognised as a potentially valuable tool for non-contact manipulation of numerous cells as well as for biological single cell analysis with non-invasive characterisation of a cell's electrical properties. Several studies have attempted to track multiple cells to characterise their cellular DEP mobility. However, they encountered difficulties in simultaneously tracking the movement of a large number of individual cells in a bright-field image sequence because of interference from the background electrode pattern. Consequently, this present study aims to develop an automatic system for imaging-based characterisation of cellular DEP mobility, which enables the simultaneous tracking of several hundred of cells inside a microfluidic device. METHODS: The proposed method for segmentation and tracking of cells consists of two main stages: pre-processing and particle centre localisation. In the pre-processing stage, background subtraction and contrast enhancement were performed to distinguish the cell region from the background image. In the particle centre localisation stage, the unmarked cell was automatically detected via graph-cut algorithm-based K-means clustering. RESULTS: Our algorithm enabled segmentation and tracking of numerous Michigan Cancer Foundation-7 (MCF-7) cell trajectories while the DEP force was oscillated between positive and negative. The cell tracking accuracy and cell count capability was at least 90% of the total number of cells with the newly developed algorithm. In addition, the cross-over frequency was measured by analysing the segmented and tracked trajectory data of the cellular movements caused by the positive and negative DEP force. The measured cross-over frequency was compared with previous results. The multi-cellular movements investigation based on the measured cross-over frequency was repeated until the viability of cells was unchanged in the same environment as in a microfluidic device. The results were statistically consistent, indicating that the developed algorithm was reliable for the investigation of DEP cellular mobility. CONCLUSION: This study developed a powerful platform to simultaneously measure the DEP-induced trajectories of numerous cells, and to investigate in a robust, efficient, and accurate manner the DEP properties at both the single cell and cell ensemble level.


Assuntos
Algoritmos , Dispositivos Lab-On-A-Chip , Movimento Celular , Eletrodos , Eletroforese
7.
Transfus Apher Sci ; 59(2): 102679, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31831328

RESUMO

BACKGROUND: The collection of a sufficient number of stem cells is important for success of allogeneic hematopoietic stem cell transplantation (HSCT). This study aimed to investigate the factors associated with successful allogeneic peripheral stem cell (PBSC) collection in healthy donors. METHODS: We retrospectively reviewed clinical data of allogeneic PBSC collection in 175 donors from 2007 to 2017 at the National Cancer Center, Korea. This study analyzed factors associated with the CD34+ cell yield such as the characteristics of donors, including age, laboratory results before apheresis, and data of procedures on the first day. The CD34+ cell dose of ≥ 4.0 × 106/kg have recently been the accepted minimum recommended dose in allogeneic HSCT settings, and this was the target dose in our study. RESULTS: The factors associated with the CD34+ cell yield were age (p = 0.007), baseline platelet (PLT) (p = 0.014), and pre-collection hematopoietic progenitor cells (HPCs) (p = 0.001) by multivariate analysis. This study represented that age, baseline platelet count, and pre-collection HPC count are important predictive factors as shown in other previous studies. CONCLUSION: Our data suggest that young age, high baseline platelet counts and high HPC counts before collection might be useful for identifying successful mobilizers.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/métodos , Adolescente , Adulto , Idoso , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doadores de Tecidos , Adulto Jovem
8.
Autophagy ; 14(8): 1347-1358, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29929436

RESUMO

TRAF6 (TNF receptor associated factor 6) plays a pivotal role in NFKB activation and macroautphagy/autophagy activation induced by TLR4 (toll like receptor 4) signaling. The objective of this study was to determine the functional role of PRDX1 (peroxiredoxin 1) in NFKB activation and autophagy activation. PRDX1 interacted with the ring finger domain of TRAF6 and inhibited its ubiquitin-ligase activity. The inhibition on TRAF6 ubiquitin-ligase activity by PRDX1 induced the suppression of ubiquitination of an evolutionarily conserved signaling intermediate in Toll pathways (ECSIT) essential for NFKB activation and BECN1 (beclin 1) required for autophagy activation. An inhibitory effect of PRDX1 on TRAF6 was clearly evidenced in PRDX1-knockdown (PRDX1KD) THP-1, PRDX1KD MDA-MB-231, and PRDX1KD SK-HEP-1 cells. PRDX1KD THP-1 cells showed increases of NFKB activation, pro-inflammatory cytokine production, NFKB-dependent gene expression induced by TLR4 stimulation, and resistance against Salmonella typhimurium infection. Additionally, migration and invasion abilities of PRDX1KD MDA-MB-231 and PRDX1KD SK-HEP-1 cancer cells were significantly enhanced compared to those of control cancer cells. Taken together, these results suggest that PRDX1 negatively regulates TLR4 signaling for NFKB activation and autophagy functions such as bactericidal activity, cancer cell migration, and cancer cell invasion by inhibiting TRAF6 ubiquitin-ligase activity. ABBREVIATIONS: 3-MA: 3-methyladenine; BECN1: beclin 1; CHUK/IKKA: conserved helix-loop-helix ubiquitous kinase; ECSIT: ECSIT signalling integrator; ELISA: enzyme-linked immunosorbent assay; NFKB: nuclear factor kappa-light-chain-enhancer of activated B cells; IB: immunoblotting; IKBKB/IKKB: inhibitor of nuclear factor kappa B kinase subunit beta; IL1B: interleukin 1 beta; IL6: interleukin 6; IP: immunoprecipitation; LPS: lipopolysaccharide; MAP1LC3/LC3: microtuble associated protein 1 light chain 3; MAP3K7/TAK1: mitogen-activated protein kinase kinase kinase 7; MAPK14/p38: mitogen-activated protein kinase 14; mROS: mitochondrial reactive oxygen species; PRDX1: peroxiredoxin 1; PRDX6: peroxiredoxin 6; RELA/p65: RELA proto-oncogene, NF-kB subunit; TRAF6 TNF: receptor associated factor 6.


Assuntos
Autofagia , NF-kappa B/antagonistas & inibidores , Peroxirredoxinas/metabolismo , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Proteína Beclina-1/metabolismo , Progressão da Doença , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Modelos Biológicos , NF-kappa B/metabolismo , Ligação Proteica , Proto-Oncogene Mas , Transdução de Sinais , Células THP-1 , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 4 Toll-Like/metabolismo , Ubiquitinação
9.
J Neurosci ; 38(6): 1351-1365, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29279307

RESUMO

Injury to the peripheral axons of sensory neurons strongly enhances the regeneration of their central axons in the spinal cord. It remains unclear on what molecules that initiate such conditioning effect. Because ATP is released extracellularly by nerve and other tissue injury, we hypothesize that injection of ATP into a peripheral nerve might mimic the stimulatory effect of nerve injury on the regenerative state of the primary sensory neurons. We found that a single injection of 6 µl of 150 µm ATP into female rat sciatic nerve quadrupled the number of axons growing into a lesion epicenter in spinal cord after a concomitant dorsal column transection. A second boost ATP injection 1 week after the first one markedly reinforced the stimulatory effect of a single injection. Single ATP injection increased expression of phospho-STAT3 and GAP43, two markers of regenerative activity, in sensory neurons. Double ATP injections sustained the activation of phospho-STAT3 and GAP43, which may account for the marked axonal growth across the lesion epicenter. Similar studies performed on P2X7 or P2Y2 receptor knock-out mice indicate P2Y2 receptors are involved in the activation of STAT3 after ATP injection or conditioning lesion, whereas P2X7 receptors are not. Injection of ATP at 150 µm caused little Wallerian degeneration and behavioral tests showed no significant long-term adverse effects on sciatic nerve functions. The results in this study reveal possible mechanisms underlying the stimulation of regenerative programs and suggest a practical strategy for stimulating axonal regeneration following spinal cord injury.SIGNIFICANCE STATEMENT Injury of peripheral axons of sensory neurons has been known to strongly enhance the regeneration of their central axons in the spinal cord. In this study, we found that injection of ATP into a peripheral nerve can mimic the effect of peripheral nerve injury and significantly increase the number of sensory axons growing across lesion epicenter in the spinal cord. ATP injection increased expression of several markers for regenerative activity in sensory neurons, including phospho-STAT3 and GAP43. ATP injection did not cause significant long-term adverse effects on the functions of the injected nerve. These results may lead to clinically applicable strategies for enhancing neuronal responses that support regeneration of injured axons.


Assuntos
Trifosfato de Adenosina/farmacologia , Axônios/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Células Receptoras Sensoriais/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Trifosfato de Adenosina/administração & dosagem , Animais , Comportamento Animal , Feminino , Proteína GAP-43/biossíntese , Proteína GAP-43/genética , Injeções , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Traumatismos dos Nervos Periféricos/genética , Traumatismos dos Nervos Periféricos/patologia , Ratos , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2Y2/genética , Fator de Transcrição STAT3/biossíntese , Fator de Transcrição STAT3/genética , Nervo Isquiático , Traumatismos da Medula Espinal/patologia , Degeneração Walleriana/genética , Degeneração Walleriana/fisiopatologia
11.
Front Immunol ; 8: 1827, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29326710

RESUMO

Ubiquitin-specific protease 14 (USP14), one of three proteasome-associated deubiquitinating enzymes, has multifunctional roles in cellular context. Here, we report a novel molecular mechanism and function of USP14 in regulating autophagy induction and nuclear factor-kappa B (NF-κB) activation induced by toll-like receptor (TLR) 4 (TLR4). USP14 interacted with tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) and interrupted the association of Beclin 1 with TRAF6, leading to inhibition of TRAF6-mediated ubiquitination of Beclin 1. Reduced expression of USP14 in USP14-knockdown (USP14KD) THP-1 cells enhanced autophagy induction upon TLR4 stimulation as shown by the increased conversion of cytosolic LC3-I to membrane-bound LC3-II. Moreover, USP14KD human breast carcinoma MDA-MB-231 cells and USP14KD human hepatic adenocarcinoma SK-HEP-1 cells showed increased cell migration and invasion, indicating that USP14 is negatively implicated in the cancer progression by the inhibition of autophagy induction. Furthermore, we found that USP14 interacted with TAK1-binding protein (TAB) 2 protein and induced deubiquitination of TAB 2, a key factor in the activation of NF-κB. Functionally, overexpression of USP14 suppressed TLR4-induced activation of NF-κB. In contrast, USP14KD THP-1 cells showed enhanced activation of NF-κB, NF-κB-dependent gene expression, and production of pro-inflammatory cytokines such as IL-6, IL-1ß, and tumor necrosis factor-α. Taken together, our data demonstrate that USP14 can negatively regulate autophagy induction by inhibiting Beclin 1 ubiquitination, interrupting association between TRAF6 and Beclin 1, and affecting TLR4-induced activation of NF-κB through deubiquitination of TAB 2 protein.

12.
J Cutan Pathol ; 43(4): 347-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26762870

RESUMO

BACKGROUND: The GATA family of transcription factors is an essential regulator of cellular proliferation and differentiation. In the skin, GATA-3 is critical for epidermal stratification and maintenance of barrier function. A role for GATA-3 in the development of human cutaneous squamous cell carcinoma (SCC) is not known. Here, we investigated GATA-3 immunohistochemical staining in premalignant and invasive cutaneous SCC from sun-exposed and sun-protected skin. METHODS: GATA-3 immunohistochemistry was performed on actinic keratoses (AK) (n = 19), in situ squamous cell carcinomas with actinic [SCCIS (A)] (n = 9) or bowenoid features [SCCIS (B)] (n = 17), well-, moderately and poorly differentiated SCC (n = 36), Bowenoid papulosis of the perineum (n = 15) and penile SCC (pSCC) (n = 10). RESULTS: We found that GATA-3 immunohistochemical staining is progressively lost in sun-exposed skin as neoplasia progresses from pre-cancerous AK to SCCIS (A), and ultimately, to SCC, which shows near absent GATA-3 staining. This reduction in GATA-3 staining is independent of histological grade in SCC. Only slight down-regulation of GATA-3 was seen in all cases of SCCIS (B) and Bowenoid papulosis, while near absent GATA-3 expression was seen in pSCC. CONCLUSION: We propose that decreased GATA-3 immunohistochemical staining is associated with cutaneous SCC progression on both sun-exposed and sun-protected sites.


Assuntos
Carcinoma de Células Escamosas , Fator de Transcrição GATA3/metabolismo , Proteínas de Neoplasias/metabolismo , Idoso , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
13.
J Cutan Pathol ; 43(4): 354-61, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26762898

RESUMO

BACKGROUND: Mantle cell lymphoma (MCL) is associated with the worst prognosis among low-grade B-cell lymphomas. While cutaneous involvement by nodal or systemic MCL is uncommon, its differentiation from primary cutaneous B-cell lymphoma (CBCL) or cutaneous involvement by other extra-cutaneous BCL is challenging as neither histomorphology nor immunophenotype can be absolutely specific. We analyzed the diagnostic utility of SOX11 immunohistochemistry in differentiating secondary cutaneous MCL from other low-grade CBCL. METHODS: Immunohistochemical staining with anti-SOX11 antibody was performed on 8 cases of secondary cutaneous MCL, 16 secondary cutaneous CLL, 20 primary cutaneous MZL, 12 cutaneous FCL (6 primary, 6 secondary), 7 primary cutaneous DLBCL, leg type, 5 systemic DLBCL and 3 B-ALL. SOX11 and cyclin D1 staining were compared in secondary cutaneous MCL. RESULTS: Nuclear SOX11 staining was seen in seven of eight cases (88%) of secondary cutaneous MCL, including a case with minimal cyclin D1 expression. All other CBCL lacked detectable nuclear SOX11 expression. The sensitivity and specificity for SOX11 in MCL were 87.5 and 100%, respectively. Both the sensitivity and specificity for combined SOX11 and cyclin D1 immunohistochemistry were 100%. CONCLUSION: SOX11 immunohistochemistry could be a useful adjunct in distinguishing secondary cutaneous MCL from other CBCL.


Assuntos
Núcleo Celular , Linfoma de Células B , Linfoma de Célula do Manto , Proteínas de Neoplasias/metabolismo , Fatores de Transcrição SOXC/metabolismo , Neoplasias Cutâneas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
14.
J Am Acad Dermatol ; 72(1): 159-67, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25440432

RESUMO

BACKGROUND: Mycosis fungoides (MF) is a neoplasm of skin-homing CD4(+) helper T (TH) lymphocytes with dysregulation of TH1 and TH2 immunity. Diagnosis of MF is challenging, as there is significant morphologic overlap with other dermatologic entities. OBJECTIVE: We investigated diagnostic utility of TH1- and TH2-specific markers, T-bet, and GATA-3, respectively, in MF and its reactive and neoplastic mimics. METHODS: Immunohistochemical staining for CD3/T-bet and CD3/GATA-3 was performed on inflammatory dermatoses (n = 56), MF (n = 37), Sezary syndrome (SS; n = 8), and cutaneous anaplastic large cell lymphoma (C-ALCL; n = 14). RESULTS: Inflammatory dermatoses showed epidermal T cells predominantly expressing GATA-3, except psoriasis, which exhibited a mixed GATA-3/T-bet staining. In contrast, neoplastic T cells in patch stage MF showed markedly increased T-bet positivity with minimal GATA-3 expression. Plaque stage MF had a mixed T-bet/GATA-3 phenotype, whereas tumor stage MF and SS exhibited diffuse GATA-3 expression. C-ALCL lacked significant staining for both markers. LIMITATIONS: Sample size was relatively small. CONCLUSIONS: A predominance of T-bet(+) T cells in the epidermis support patch stage MF over dermatitis. A predominance of GATA-3(+) T cells in the dermis support CD30(+) MF with large cell transformation over C-ALCL. These stains do not allow distinction between dermatitis and cutaneous infiltrates of SS.


Assuntos
Dermatite/imunologia , Fator de Transcrição GATA3/biossíntese , Linfoma Cutâneo de Células T/imunologia , Neoplasias Cutâneas/imunologia , Proteínas com Domínio T/biossíntese , Linfócitos T Auxiliares-Indutores/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Dermatite/diagnóstico , Feminino , Humanos , Linfoma Cutâneo de Células T/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/diagnóstico , Adulto Jovem
15.
Menopause ; 18(3): 307-13, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21107301

RESUMO

OBJECTIVE: Osteoporosis is a major health problem worldwide, and most current therapy used in osteoporosis treatment acts by either increasing bone formation or decreasing bone resorption. However, the adverse effects of these therapies may preclude their long-term use. We examined the effects of egg yolk water-soluble peptide (YPEP) on bone metabolism as an alternative to current therapeutic agents in ovariectomized (OVX) rats. METHODS: In the first step, the in vitro effects of YPEP on bone loss were determined. The proliferation, collagen content, and alkaline phosphatase activity of preosteoblastic MC3T3-E1 cells and osteoclastogenesis from bone marrow-derived precursor cells were measured. The in vivo experiment confirmed the positive effect of YPEP on bone tissue. Three-month-old female Sprague-Dawley rats were either sham operated or ovariectomized and fed commercial chow diet or 0.1% YPEP-supplemented diet for 3 month. RESULTS: YPEP increased preosteoblastic MC3T3-E1 cell proliferation and alkaline phosphatase activity in a dose-dependent manner. Collagen content was also increased by YPEP treatment. Furthermore, YPEP potently suppressed osteoclastogenesis from bone marrow-derived precursor cells. YPEP (100 µg/mL) abolished the formation of osteoclasts positive for tartrate-resistant acid phosphatase. OVX rats supplemented with YPEP showed an osteoprotective effect, as the bone mineral density and cortical thickness in the tibia were increased compared with the OVX controls. Moreover, histological data indicate that YPEP prevented the cancellous bone loss induced by ovariectomy. None of these protective effects were observed in casein-treated rats. CONCLUSIONS: The present study suggests that YPEP is a promising alternative to current therapeutic agents for the management of osteoporosis.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Proteínas Dietéticas do Ovo/uso terapêutico , Osteoporose/prevenção & controle , Fosfatase Alcalina/análise , Fosfatase Alcalina/sangue , Animais , Densidade Óssea/efeitos dos fármacos , Células da Medula Óssea/citologia , Reabsorção Óssea/tratamento farmacológico , Osso e Ossos/anatomia & histologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Colágeno/análise , Proteínas Dietéticas do Ovo/administração & dosagem , Feminino , Fêmur/anatomia & histologia , Osteoblastos/química , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia , Ovariectomia , Ratos , Ratos Sprague-Dawley
16.
Br J Haematol ; 124(3): 376-84, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14717787

RESUMO

Platelet microparticles (PMP) are endogenous substances generated during the coagulation process in a hypercoagulable state. This study demonstrated that PMP promote the proliferation and survival, migration, and tube formation in human umbilical vein endothelial cells (HUVEC). Heat-treated PMP did not significantly decrease the angiogenic activity in HUVEC compared with that of the untreated PMP. Meanwhile when PMP were treated with activated charcoal, a procedure known to remove the lipid growth factors, the angiogenic activity was significantly reduced. These results suggest that the lipid component(s) of the PMP may be major active factor(s) and that protein component(s) may be minor contributor(s). PMP were also shown to augment endothelial progenitor cell differentiation in peripheral blood mononuclear cells. In addition, PMP-stimulated proliferation, chemotaxis and tube formation of the HUVEC was mediated via the Pertussis toxin-sensitive G protein, extracellular signal-regulated kinase and the phosphoinositide 3-kinase pathway. Herein, a new action of PMP was demonstrated to be a potent angiogenic stimulator. It is expected that in pathological states such as a growing tumour, PMP shed from the circulating platelets may reach adequate concentrations and that the elevated levels of PMP could contribute to florid formation of new blood vessels.


Assuntos
Coagulação Sanguínea , Plaquetas , Células Endoteliais/fisiologia , Endotélio Vascular/fisiologia , Neovascularização Fisiológica , Apoptose , Capilares/citologia , Diferenciação Celular , Divisão Celular , Células Cultivadas , Quimiotaxia , Humanos , Microscopia de Fluorescência , Células-Tronco/citologia , Fator A de Crescimento do Endotélio Vascular/farmacologia
17.
Infect Immun ; 71(11): 6213-21, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14573639

RESUMO

Host defense against the opportunistic pathogen Pneumocystis carinii requires functional interactions of many cell types. Alveolar macrophages are presumed to be a vital host cell in the clearance of P. carinii, and the mechanisms of this interaction have come under scrutiny. The macrophage mannose receptor is believed to play an important role as a receptor involved in the binding and phagocytosis of P. carinii. Although there is in vitro evidence for this interaction, the in vivo role of this receptor in P. carinii clearance in unclear. Using a mouse model in which the mannose receptor has been deleted, we found that the absence of this receptor is not sufficient to allow infection by P. carinii in otherwise immunocompetent mice. Furthermore, when mice were rendered susceptible to P. carinii by CD4(+) depletion, mannose receptor knockout mice (MR-KO) had pathogen loads equal to those of wild-type mice. However, the MR-KO mice exhibited a greater influx of phagocytes into the alveoli during infection. This was accompanied by increased pulmonary pathology in the MR-KO mice, as well as greater accumulation of glycoproteins in the alveoli (glycoproteins, including harmful hydrolytic enzymes, are normally cleared by the mannose receptor). We also found that the surface expression of the mannose receptor is not downregulated during P. carinii infection in wild-type mice. Our findings suggest that while the macrophage mannose receptor may be important in the recognition of P. carinii, in vivo, this mechanism may be redundant, and the absence of this receptor may be compensated for.


Assuntos
Lectinas Tipo C/fisiologia , Macrófagos/fisiologia , Lectinas de Ligação a Manose/fisiologia , Infecções por Pneumocystis/imunologia , Receptores de Superfície Celular/fisiologia , Animais , Linfócitos T CD4-Positivos/fisiologia , Suscetibilidade a Doenças , Manose/metabolismo , Receptor de Manose , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Soroalbumina Bovina/metabolismo
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