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1.
Therap Adv Gastroenterol ; 15: 17562848221145552, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36600685

RESUMO

Background: Since initially detected in late December 2019, the novel coronavirus disease 2019 (COVID-19) outbreak rapidly swept the world, which has profoundly affected healthcare system and clinical practice in the management of gastrointestinal diseases. Objectives: We aimed to evaluate the impact of COVID-19 pandemic on the pattern of hospital admissions and healthcare services for acute pancreatitis (AP). Design: We conducted a retrospective observational cohort study using the anonymized electronic medical records. Methods: This single-center, retrospective observational study from a regional medical center in the northeast of China included all consecutively admitted patients with AP from 23 January to 10 June 2020 (during the COVID-19 outbreak in Harbin), compared with the equivalent period of the previous year, in terms of demographics, clinical characteristics, and in-hospital outcomes. Results: In this article, we observed a reduction in AP admissions after the beginning of COVID-19 outbreak. With the prolonged time from symptom onset to hospitalization [32.0 (22.0-72.0) versus 18.0 (12.0-24.0) h; p < 0.001], a higher proportion of AP patients developed acute renal failure (14.0% versus 7.4%, p = 0.004) and acute necrotic collection (16.5% versus 11.2%; p = 0.038) in the COVID-19 era. The percentage of alcohol etiology significantly decreased after the implementation of social restriction measures (11.5% versus 20.4%; p = 0.002), whereas biliary etiology was numerically more common amidst the COVID-19 era (41.6% versus 32.6%; p = 0.014). No significant differences were found in the rates of intensive care unit admission and mortality between the two groups. Conclusion: This study preliminarily demonstrated the descending trend and delay in hospital presentations for AP during the outbreak of COVID-19. Given that the pandemic may persist for several years, adjustments of medical services according to the varying degrees of local breakouts are imperative to provide appropriate care for AP patients and diminish the risk of viral transmission. Registration: ClincialTrials.gov number ChiCTR2100043350.

2.
Cell Death Dis ; 12(11): 996, 2021 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-34697288

RESUMO

Chronic pancreatitis (CP) is described as progressive inflammatory fibrosis of pancreas, accompanied with irreversible impaired endocrine and exocrine insufficiency. Pancreatic stellate cells (PSCs) are widely distributed in the stroma of the pancreas and PSCs activation has been shown as one of the leading causes for pancreatic fibrosis. Our previous study has revealed that autophagy is dramatically activated in CP tissues, which facilitates PSCs activation and pancreatic fibrosis. Long non-coding RNAs (LncRNAs) have been recognized as crucial regulators for fibrosis-related diseases. LncRNAs interact with RNA binding protein or construct competitive endogenous RNA (ceRNA) hypothesis which elicited the fibrotic processes. Until now, the effects of lncRNAs on PSCs activation and pancreatic fibrosis have not been clearly explored. In this study, a novel lncRNA named Lnc-PFAR was found highly expressed in mouse and human CP tissues. Our data revealed that Lnc-PFAR facilitates PSCs activation and pancreatic fibrosis via RB1CC1-induced autophagy. Lnc-PFAR reduces miR-141 expression by suppressing pre-miR-141 maturation, which eventually upregulates the RB1CC1 and fibrosis-related indicators expression. Meanwhile, Lnc-PFAR enhanced PSCs activation and pancreatic fibrosis through trigging autophagy. Our study interrogates a novel lncRNA-induced mechanism in promoting the development of pancreatic fibrosis, and Lnc-PFAR is suggested to be a prospective therapeutic target in clinical scenarios.


Assuntos
Fibrose/complicações , MicroRNAs/metabolismo , Pancreatite Crônica/genética , RNA Longo não Codificante/metabolismo , Animais , Autofagia , Estudos de Casos e Controles , Doença Crônica , Modelos Animais de Doenças , Humanos , Camundongos , Pancreatite Crônica/patologia
3.
Cell Death Discov ; 6(1): 94, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083016

RESUMO

Postoperative pancreatic fistula (POPF) is a common and dreaded complication after pancreaticoduodenectomy (PD). The gut microbiota has been considered as an crucial mediator of postoperative complications, however, the precise roles of gut microbiota in POPF are unclear. A prospective study was developed to explore the effects of somatostatin on gut microbiota and we aim to identify the microbial alterations in the process of POPF. A total of 45 patients were randomly divided into PD group or additional somatostatin therapy group. The fecal sample of each patient was collected preoperatively and postoperatively and the gut microbiota was analyzed by 16S rRNA sequencing. Our study found that somatostatin therapy was independent risk factor for the occurrence of POPF, and it reduced the microbial diversity and richness in patients. At genus level, somatostatin therapy led to a decreased abundance in Bifidobacterium, Subdoligranulum and Dubosiella, whereas the abundance of Akkermansia, Enterococcus and Enterobacter were increased. The abundance levels of certain bacteria in the gut microbiota have significantly shifted in patients with POPF. The LEfSe analysis revealed that Ruminococcaceae could be used as microbial markers for distinguishing patients with high risk of POPF. Furthermore, Verrucomicrobia and Akkermansia could be used as preoperative biomarkers for identifying patients without POPF. Our prospective study highlights the specific communities related with somatostatin therapy and discovers POPF-associated microbial marker, which suggests that gut microbiota may become a diagnostic biomarker and potential therapeutic target for POPF.

6.
Cell Death Dis ; 9(10): 952, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30237496

RESUMO

Chronic pancreatitis (CP) is described as a progressive fibro-inflammatory disorder of the exocrine disease, which eventually leads to damage of the gland. Excessive activation of pancreatic stellate cells (PSCs) is a critical participant in the initiation of CP. Autophagy is involved in multiple degeneration and inflammation in acute pancreatitis and CP. In our study, we report that retinoblastoma coiled coil protein 1 (RB1CC1) expression and the autophagic level are elevated in activated PSCs. RB1CC1 is positively correlated with pancreatic fibrogenesis in tissues and plasma of CP patients. Knockdown of RB1CC1 restrains alpha smooth muscle actin (α-SMA) and collagen expressions, and autophagy in activated PSCs in vitro. Furthermore, we show that RB1CC1 induces PSC activation via binding to ULK1 promoter and the direct interaction with ULK1 protein. These suppress ULK1 expression and its kinase activity. In mice, knockdown of RB1CC1 blocks autophagy and then inhibits the pancreatic duct ligation-induced pancreatic fibrosis. Consequently, our study highlights that RB1CC1-mediated autophagy is a key event for the activation of PSCs. Inhibition of RB1CC1 alleviates autophagy, which plays a critical role in anti-fibrotic activation in PSCs and CP progression. RB1CC1 could be a novel strategy for the treatment of pancreatic fibrosis.


Assuntos
Autofagia/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Pâncreas/metabolismo , Pâncreas/patologia , Células Estreladas do Pâncreas/citologia , Células Estreladas do Pâncreas/metabolismo , Pancreatite Crônica/metabolismo , Pancreatite Crônica/patologia , Proteínas Tirosina Quinases/metabolismo , Animais , Autofagia/genética , Proteínas Relacionadas à Autofagia , Western Blotting , Células Cultivadas , Ensaio de Desvio de Mobilidade Eletroforética , Fibrose/metabolismo , Fibrose/patologia , Imunofluorescência , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pancreatite Crônica/genética , Proteínas Tirosina Quinases/genética
7.
Pancreas ; 47(4): 436-443, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29517639

RESUMO

OBJECTIVES: This study aimed to assess the need of surgical necrosectomy after percutaneous catheter drainage (PCD) for infected necrotizing pancreatitis. METHODS: The clinical data of documented/suspected patients who were treated with a step-up approach were extracted and analyzed. RESULTS: Of the 329 patients enrolled, the initial PCD was performed at 12 (interquartile range, 9-15) days since onset and 35.3% were cured by PCD alone. In the pre-PCD model, mean computed tomographic (CT) density of necrotic fluid collection (NFC; P < 0.001), and multiple-organ failure (MOF; P < 0.001) within 24 hours before the initial PCD were independent risk factors, and a combination of the previously mentioned 2 factors produced an area under the curve of 0.775. In the post-PCD model, mean CT density of NFC (P = 0.041), MOF (P = 0.002), and serum procalcitonin level (P = 0.035) 3 days after the initial PCD were independent risk factors, and a combination of these previously mentioned factors produced an area under the curve of 0.642. CONCLUSIONS: Both mean CT density of NFC and MOF are independent pre- and post-PCD risk factors for the need of necrosectomy after PCD. Post-PCD serum procalcitonin level might be a respondent factor that is correlated with the necessity of necrosectomy.


Assuntos
Drenagem/métodos , Infecções/cirurgia , Pancreatite Necrosante Aguda/cirurgia , Adulto , Líquidos Corporais/química , Catéteres , Feminino , Humanos , Infecções/etiologia , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/complicações , Insuficiência de Múltiplos Órgãos/diagnóstico por imagem , Necrose , Pancreatite Necrosante Aguda/complicações , Fatores de Risco , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Medicine (Baltimore) ; 96(30): e7487, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28746189

RESUMO

To assess the association between the clinical parameters within 48 hours of admission and the occurrence of infected pancreatic necrosis (IPN) during the late phase of necrotizing pancreatitis (NP).All patients were divided into 2 groups, the IPN and non-IPN groups. The clinical data were retrospectively analyzed. Univariate and multivariate logistic regression analyses were performed to evaluate the relationship between clinical parameters and IPN secondary to NP. The performance of each independent variable was plotted by the receiver-operating characteristic (ROC) curve. Consequently, the cut-off level of each independent variable with its sensitivity and specificity was calculated.A total of 215 patients were enrolled in our study. Among them, 87 (40.5%) patients developed IPNs after a median of 13.5 (9.5-23.0) days from admission. Multivariate analysis indicated that the level of hematocrit (HCT) from 40% to 50% (P=.012, odds ratio (OR) = 2.407), HCT over 50% (P < .009, OR = 6.794), blood urea nitrogen (BUN) (P = .040, OR = 1.894), C-reactive protein (CRP) (P = .043, OR = 1.837), and procalcitonin (PCT) (P = .002, OR = 2.559) were independent risk factors of IPN secondary to NP. The ROC cures revealed that the area under the ROC (AUC) of the maximum level of HCT, BUN, CRP, and PCT within 48 hours of admission was 0.687, 0.620, 0.630, and 0.674 respectively. Furthermore, the combination of these 4 individual parameters contributes to a more preferable AUC of 0.789 with a sensitivity of 67.8% and specificity of 77.3%.The maximum levels of PCT, CRP, HCT, and BUN within 48 hours of admission are independent factors of IPN and their combination might accurately predict the occurrence of IPN secondary to NP.


Assuntos
Infecções Bacterianas/diagnóstico , Infecções Bacterianas/etiologia , Pancreatite Necrosante Aguda/sangue , Pancreatite Necrosante Aguda/complicações , Adolescente , Adulto , Biomarcadores/sangue , Nitrogênio da Ureia Sanguínea , Proteína C-Reativa/metabolismo , Calcitonina/sangue , Tratamento Conservador , Diagnóstico Precoce , Feminino , Hematócrito , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/etiologia , Necrose/terapia , Pancreatite Necrosante Aguda/imunologia , Pancreatite Necrosante Aguda/terapia , Admissão do Paciente , Curva ROC , Fatores de Risco , Fatores de Tempo , Adulto Jovem
9.
Chin J Nat Med ; 14(9): 677-682, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27667513

RESUMO

The present study was designed to identify immunomodulatory components from the leech salivary gland of Haemadipsa sylvestris. The Sephadex G-50, Resource(TM) S column chromatography and reverse-phase high performance liquid chromatography (RP-HPLC) were used to isolate and purify the salivary gland extracts (SGE). Structural analysis of isolated compounds was based on Edman degradation and matrix assisted laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS). The cDNA encoding the precursor of the compound was cloned from the cDNA library of the salivary gland of H. sylvestris. The levels of inflammatory mediators, including tumor necrosis factor-α (TNF-α), interferon γ (IFN-γ), interleukin-6 (IL-6), and monocyte chemotactic protein-1 (MCP-1) were assayed using an enzyme-linked immunosorbent assay (ELISA). The effects on cell proliferation and cell viability were observed using MTT assay. A novel neuropeptide Y (Neuropeptide Y-HS) from the leech salivary gland of H. sylvestris was purified and characterized. It was composed of 36 amino acid residues and the amino acid sequence was determined to be FLEPPERPAVFTSVEQMKSYIKALNDYYLLLGRPRF-NH2, containing an amidated C-terminus. It showed significant inhibitory effects on the production of inflammatory cytokines including TNF-α, IFN-γ, IL-6, and MCP-1. Neuropeptide Y was identified from leeches for the first time. The presence of neuropeptide Y-HS in leech salivary gland may help get blood meal from hosts and inhibit inflammation.


Assuntos
Sanguessugas/química , Neuropeptídeo Y/administração & dosagem , Neuropeptídeo Y/química , Sequência de Aminoácidos , Animais , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/química , Fatores Imunológicos/genética , Inflamação/tratamento farmacológico , Inflamação/imunologia , Interferon gama/imunologia , Interleucina-6/imunologia , Espectrometria de Massas , Camundongos , Dados de Sequência Molecular , Neuropeptídeo Y/genética , Mapeamento de Peptídeos , Glândulas Salivares/química , Fator de Necrose Tumoral alfa/imunologia
10.
Mol Cancer Ther ; 15(9): 2232-43, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27371730

RESUMO

Recently, pancreatic ductal adenocarcinoma (PDAC) has emerged as one of the most aggressive malignant tumors with the worst prognosis. Previous studies have demonstrated that long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is increased in pancreatic cancer and is identified as a diagnostic biomarker. Nonetheless, the molecular mechanism of elevated MALAT1 levels and tumor aggressiveness remains unknown. In this study, MALAT1 was found to be highly expressed in PDAC tissues, and elevated expression was associated with poorer prognoses. In addition, MALAT1 was positively linearly correlated with the expression of LC3B mRNA. Furthermore, several molecules involved in cellular autophagic flux were modulated following the downregulation of MALAT1, including LC3, P62, and LAMP-2. Mechanistically, we found that MALAT1 interacted with RNA binding protein HuR, and silencing of MALAT1 greatly enhanced the posttranscriptional regulation of TIA-1 and had further effects on inhibiting autophagy. MALAT1 was speculated to regulate tumorigenesis via HuR-TIA-1-mediated autophagic activation. Hence, we investigated the biological properties of MALAT1 in terms of tumor proliferation and metastasis by promoting autophagy in vitro In brief, these data demonstrate that MALAT1 could facilitate the advanced progression of tumors in vivo Our study highlights the new roles of MALAT1 on protumorigenic functioning and anticancer therapy via activating autophagy in pancreatic cancer. Mol Cancer Ther; 15(9); 2232-43. ©2016 AACR.


Assuntos
Autofagia/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , RNA Longo não Codificante/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Proteína Semelhante a ELAV 1/genética , Feminino , Inativação Gênica , Humanos , Camundongos , Metástase Neoplásica , Neoplasias Pancreáticas/mortalidade , Proteínas de Ligação a Poli(A)/genética , Prognóstico , Interferência de RNA , Antígeno-1 Intracelular de Células T , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Nat Prod Bioprospect ; 4(5): 309-13, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25294221

RESUMO

Various kinds of biologically active peptides have previously been isolated from the skin secretions of Amolops loloensis frog, such as antimicrobial peptides, bradykinin-like peptides and algesic peptides. A novel insulinotropic peptide named amolopin was identified in A. loloensis frog's skin secretion. Its primary structure sequence was determined by Edman degradation as: FLPIVGKSLSGLSGKL-NH2. BLAST search indicates that the amino acid sequence of amolopin is quite different from other known insulin secretagogues, including mastoparan, exendins and α-latrotoxin, nor does it like incretins (e.g. glucagons like peptide-1 and glucose-dependent insulinotropic ploypeptide) either. However, amolopin shows certain structural similarity with amphibian antimicrobial temporins and vespid chemotactic peptides isolated from Vespa magnifica. Amolopin can stimulate insulin release in INS-1 cells in a dose-dependent manner. Primary investigation on its action mechanisms reveals that amolopin does not increase the influx of Ca(2+). In conclusion, a novel 16-amino acid peptide with insulin-releasing activity is initially discovered from the skin secretion of A. loloensis frog. Further work is necessary to evaluate its potential as novel anti-diabetic candidate.

12.
Zhonghua Wai Ke Za Zhi ; 51(6): 493-8, 2013 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-24091261

RESUMO

OBJECTIVE: To investigate the feasibility and clinical value of the step-up approach for severe acute pancreatitis (SAP). METHODS: Clinical data of 121 SAP patients admitted between January 2002 and December 2011 were retrospectively analyzed. Fifty-eight patients (37 males and 21 females, aged from 20 to 72 years, mean 47.6 years) in the group of direct open necrosectomy from January 2002 to December 2006 were performed laparotomy through removal of all necrotic tissue. Sixty-three patients (42 males and 21 females, aged from 19 to 78 years, mean 46.2 years) of step-up approach from January 2007 to December 2011 underwent percutaneous catheter drainage through retroperitoneum or omental bursa guided by B-type ultrasonography for the first therapy, and then, according to the pathogenetic condition, if necessary, followed by a small incisional necrosectomy along the drainage tube. The two groups were compared for the rates of postoperative complications, death, transfusion and length of stay, medical costs. RESULTS: The rates of total postoperative complications, organ dysfunction, alimentary tract fistula and incisional hernia in step-up approach group were significantly lower than those of direct open necrosectomy group (31.7% vs. 62.1%, 14.3% vs. 37.5%, 6.3% vs. 19.0%, 9.5% vs. 29.3%; χ(2) = 4.43 to 11.17, P = 0.001 to 0.035). The other complications had no significant differences between the two groups (P > 0.05). Patients in step-up approach group had a lower rates of transfusion (44.4% vs. 70.7%, χ(2) = 8.488, P = 0.004), fewer medical costs of transfusion and hospital stay, compared with those in direct open necrosectomy group ((2525 ± 4573) yuan vs. (4770 ± 6867) yuan, t = 2.131, P = 0.035; (171 213 ± 50 917) yuan vs. (237 874 ± 67 832) yuan, t = 2.496, P = 0.014). There were no significant differences of length of stay and mortality between two groups (P > 0.05). CONCLUSION: Step-up approach for SAP which can reduce the rates of postoperative complications, transfusion and medical costs has significant feasibility and great clinical value.


Assuntos
Pancreatite Necrosante Aguda/cirurgia , Paracentese , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite Necrosante Aguda/economia , Paracentese/economia , Cavidade Peritoneal/cirurgia , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
PLoS One ; 6(8): e23752, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21887310

RESUMO

BACKGROUND: Epithelial to mesenchymal transition (EMT) induced by hypoxia is one of the critical causes of treatment failure in different types of human cancers. NF-κB is closely involved in the progression of EMT. Compared with HIF-1α, the correlation between NF-κB and EMT during hypoxia has been less studied, and although the phenomenon was observed in the past, the molecular mechanisms involved remained unclear. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that hypoxia or overexpression of hypoxia-inducible factor-1α (HIF-1α) promotes EMT in pancreatic cancer cells. On molecular or pharmacologic inhibition of NF-κB, hypoxic cells regained expression of E-cadherin, lost expression of N-cadherin, and attenuated their highly invasive and drug-resistant phenotype. Introducing a pcDNA3.0/HIF-1α into pancreatic cancer cells under normoxic conditions heightened NF-κB activity, phenocopying EMT effects produced by hypoxia. Conversely, inhibiting the heightened NF-κB activity in this setting attenuated the EMT phenotype. CONCLUSIONS/SIGNIFICANCE: These results suggest that hypoxia or overexpression of HIF-1α induces the EMT that is largely dependent on NF-κB in pancreatic cancer cells.


Assuntos
Transição Epitelial-Mesenquimal , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , NF-kappa B/fisiologia , Neoplasias Pancreáticas/patologia , Caderinas , Linhagem Celular Tumoral , Expressão Gênica , Humanos , Hipóxia/complicações , Subunidade alfa do Fator 1 Induzível por Hipóxia/administração & dosagem , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Pancreáticas/metabolismo , Fenótipo , Células Tumorais Cultivadas
14.
Cancer Chemother Pharmacol ; 68(6): 1421-30, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21479633

RESUMO

PURPOSE: Dihydroartemisinin (DHA) has recently shown antitumor activity in human pancreatic cancer cells. However, its effect on antiangiogenic activity in pancreatic cancer is unknown, and the mechanism is unclear. This study was aimed to investigate whether DHA would inhibit angiogenesis in human pancreatic cancer. METHODS: Cell viability and proliferation, tube formation of human umbilical vein endothelial cells (HUVECs), nuclear factor (NF)-κB DNA-binding activity, expressions of vascular endothelial growth factor (VEGF), interleukin (IL)-8, cyclooxygenase (COX)-2, and matrix metalloproteinase (MMP)-9 were examined in vitro. The effect of DHA on antiangiogenic activity in pancreatic cancer was also assessed using BxPC-3 xenografts subcutaneously established in BALB/c nude mice. RESULTS: DHA inhibited cell proliferation and tube formation of HUVECs in a time- and dose-dependent manner and also reduced cell viability in pancreatic cancer cells. DHA significantly inhibited NF-κB DNA-binding activity, so as to tremendously decrease the expression of NF-κB-targeted proangiogenic gene products: VEGF, IL-8, COX-2, and MMP-9 in vitro. In vivo studies, DHA remarkably reduced tumor volume, decreased microvessel density, and down-regulated the expression of NF-κB-related proangiogenic gene products. CONCLUSIONS: Inhibition of NF-κB activation is one of the mechanisms that DHA inhibits angiogenesis in human pancreatic cancer. We also suggest that DHA could be developed as a novel agent against pancreatic cancer.


Assuntos
Inibidores da Angiogênese/farmacologia , Artemisininas/farmacologia , NF-kappa B/antagonistas & inibidores , Neovascularização Patológica/prevenção & controle , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Humanos , Masculino , Camundongos , Neoplasias Pancreáticas/irrigação sanguínea
15.
Zhonghua Wai Ke Za Zhi ; 48(7): 530-4, 2010 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-20646665

RESUMO

OBJECTIVE: To investigate the anti-tumor activity of combined gemcitabine with dihydroartemisinin, and the mechanism of the anti-tumor effect of gemcitabine enhanced by dihydroartemisinin on pancreatic cancer. METHODS: For cultured cells, cell growth was determined by the MTT assay and apoptosis was evaluated by flow cytometry analysis and confocal laser scanning microscope stained with Annexin V-FITC/PI. The nuclear extract for determining NF-kappaB DNA-binding activity was analyzed by EMSA, while nuclear P65 and its downstream gene expression was determined by Western blot assay. BxPC-3 cells were injected subcutaneously into nude mice to establish pancreatic xenograft tumors and the tumor volume was monitored after exposure to agents. TUNEL assay was used to assess tumor cell apoptosis in tumor tissue. RESULTS: After combination of gemcitabine and dihydroartemisinin treatment, the proliferative inhibition rates of pancreatic cancer cells BxPC-3 and Panc-1 reached up to (81.1 +/- 3.9)% and (76.5 +/- 3.3)%, and the apoptosis rates were up to (53.6 +/- 3.8)% and (48.3 +/- 4.3)%, the differences were significantly (P < 0.01) compared with gemcitabine [(24.8 +/- 2.9)% and (21.8 +/- 3.5)%]. All the treatment groups inhibited the growth of pancreatic xenograft tumors in nude mice. The tumor volume and apoptosis index were (262 +/- 37) mm(3) and (50 +/- 4)% respectively in the combined treatment, compared to those of [(384 +/- 56) mm(3) and (25 +/- 3)%] in gemcitabine, the differences were significantly (P < 0.05). EMSA showed that gemcitabine alone obviously enhanced its DNA-binding activity compared to control. However, dihydroartemisinin significantly reduced its DNA-binding activity, so that abrogated the inducing effect of gemcitabine on NF-kappaB activation. Western blot assay indicated that dihydroartemisinin downregulated expression of nuclear P65, and combined treatment not only downregulated the expression of Cyclin D1, Bcl-xL and Bcl-2 while upregulated Bax, thus reduced the Bcl-2/Bax ratio, but also increased the caspase-3 activation, all of which increased apoptosis in both BxPC-3 and Panc-1 cells. CONCLUSION: Dihydroartemisinin significantly abrogated the inducing effect of gemcitabine on NF-kappaB activation and downregulated the expression of NF-kappaB targeted gene products, which may be one possible mechanism by which dihydroartemisinin augments the anti-tumor effect of gemcitabine on pancreatic cancer.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Artemisininas/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Desoxicitidina/uso terapêutico , Humanos , Masculino , Camundongos , Camundongos Nus , NF-kappa B/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
16.
Cancer Lett ; 293(1): 99-108, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20137856

RESUMO

Gemcitabine is currently the best known chemotherapeutic option available for pancreatic cancer, but the tumor returns de novo with acquired resistance over time, which becomes a major issue for all gemcitabine-related chemotherapies. In this study, for the first time, we demonstrated that dihydroartemisinin (DHA) enhances gemcitabine-induced growth inhibition and apoptosis in both BxPC-3 and PANC-1 cell lines in vitro. The mechanism is at least partially due to DHA deactivates gemcitabine-induced NF-kappaB activation, so as to decrease tremendously the expression of its target gene products, such as c-myc, cyclin D1, Bcl-2, Bcl-xL. In our in vivo studies, gemcibabine also manifested remarkably enhanced anti-tumor effect when combined with DHA, as manifested by significantly increased apoptosis, as well as decreased Ki-67 index, NF-kappaB activity and its related gene products, and predictably, significantly reduced tumor volume. We concluded that inhibition of gemcitabine-induced NF-kappaB activation is one of the mechanisms that DHA dramatically promotes its anti-tumor effect on pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Artemisininas/farmacologia , Desoxicitidina/análogos & derivados , NF-kappa B/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Artemisininas/administração & dosagem , Processos de Crescimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , NF-kappa B/genética , NF-kappa B/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
17.
Zhonghua Wai Ke Za Zhi ; 47(19): 1459-63, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-20092758

RESUMO

OBJECTIVE: To observe the therapeutic effect of hyperbaric oxygen (HBO) on acute pancreatitis (AP) by downregulating hypoxia-inducible factor (HIF). METHODS: Forty Wistar rats were randomly divided into 4 groups (n = 10): sham group, AP group, normo-oxygen group (NP) and HBO group. At 4 hours after taurocholate-induced AP, the rats of NP group and HBO group were respectively treated with oxygen or HBO for 90 min. Several parameters were measured to evaluate oxygen stress after treatment including oxygen saturation (SaO2), partial pressure of oxygen (PO2), pH, and serum LDH. Pancreatic tissues were subjected to histopathological analysis, immunostained, and homogenized for Western blotted analysis of HIF-1alpha and VEGF, and measuring myeloperoxidase activity. The serum TNF-alpha and pancreatic histopathological scores were evaluated the severity of AP. RESULTS: It was proved by immunohistochemisty that HIF in acinar cell and polymorphonuclear leukocytes (PMNs) was activated and transferred from cytoplasm into nucleus in AP group, NP group, and HBO group, following upregulation of VEGF. HBO therapy elevated blood SaO2 (99.6% +/- 0.7% vs. 87.7% +/- 1.8% or 91.2% +/- 2.5%, P < 0.05) and PaO2 [(369.1 +/- 67.6) mm Hg (1 mm Hg = 0.133 kPa) vs. (86.6 +/- 5.6) mm Hg or (99.9 +/- 4.0) mm Hg, P < 0.05]. HBO therapy attenuated the severity of AP through inhibiting AP-induced upregulation of HIF-1alpha and VEGF, as evidenced by reducing histopathological scores (12.40 +/- 1.21 vs. 16.45 +/- 1.10 or 16.38 +/- 1.10, P < 0.05), dry/wet weight ratio of pancreatic tissues, and myeloperoxidase activity. CONCLUSIONS: HIF-1alpha plays a key role in the pathogenesis of AP. HBO therapy attenuates the severity of AP through downregulating the expression of HIF-1alpha.


Assuntos
Oxigenoterapia Hiperbárica , Pancreatite , Animais , Oxigênio , Pancreatite/terapia , Ratos Sprague-Dawley , Ratos Wistar
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