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1.
J Gastroenterol ; 49(3): 481-91, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23475323

RESUMO

BACKGROUND: Dipeptidyl peptidase-4 inhibitor (DPP4-I) is clinically used as a new oral antidiabetic agent. Although DPP4 is reportedly associated with the progression of chronic liver diseases, the effect of DPP4-I on liver fibrosis development is still obscure. This study was designed to elucidate the effect of DPP4-I on liver fibrosis development in conjunction with the activated hepatic stellate cells (Ac-HSCs). METHODS: The antifibrotic effect of DPP4-I was assessed in vivo and in vitro using porcine serum-induced experimental liver fibrosis model. DPP4-I, sitagliptin, at a clinically comparable low dose was administered by gavage daily. RESULTS: DPP4-I significantly attenuated liver fibrosis development along with the suppression of hepatic transforming growth factor (TGF)-ß1, total collagen, and tissue inhibitor of metalloproteinases-1 in a dose-dependent manner. These suppressive effects occurred almost concurrently with the attenuation of HSCs activation. Our in vitro studies showed that DPP4-I inhibited platelet-derived growth factor-BB-mediated proliferation of the Ac-HSCs as well as upregulation of TGF-ß1 and α1(I)-procollagen at magnitudes similar to those of the in vivo studies. The inhibitory effects of DPP4-I against HSCs proliferation and fibrogenic gene expression are mediated through the inhibition of the phosphorylation of ERK1/2, p38 and Smad2/3, respectively. CONCLUSIONS: DPP4-I markedly inhibits liver fibrosis development in rats via suppression of HSCs proliferation and collagen synthesis. These suppressive effects are associated with dephosphorylation of ERK1/2, p38 and Smad2/3 in the HSCs. Since DPP4-I is widely used in clinical practice, this drug may represent a potential new therapeutic strategy against liver fibrosis in the near future.


Assuntos
Inibidores da Dipeptidil Peptidase IV/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática Experimental/prevenção & controle , Pirazinas/farmacologia , Triazóis/farmacologia , Animais , Becaplermina , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , Inibidores da Dipeptidil Peptidase IV/administração & dosagem , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-sis/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-sis/metabolismo , Pirazinas/administração & dosagem , Ratos , Ratos Endogâmicos F344 , Fosfato de Sitagliptina , Suínos , Fator de Crescimento Transformador beta1/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo , Triazóis/administração & dosagem
2.
Hepatol Res ; 43(7): 765-74, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23163573

RESUMO

AIM: Both angiotensin-II (AT-II) and aldosterone (Ald) play pivotal roles in the pathogenesis of diseases in several organs including the liver. We previously reported that suppression of AT-II and Ald with angiotensin-converting enzyme inhibitor (ACE-I) and selective Ald blocker (SAB), respectively, attenuated the rat liver fibrogenesis and hepatocarcinogenesis. The aim of our current study was to elucidate the combined effects of ACE-I and SAB in the progression of a non-diabetic rat model of steatohepatitis, and the possible mechanisms involved. METHODS: In the choline-deficient L-amino acid-defined (CDAA) diet-induced model, the effects of ACE-I and SAB on liver fibrosis development and hepatocarcinogenesis were elucidated, especially in conjunction with neovascularization. RESULTS: Treatment with both ACE-I and SAB suppressed the development of liver fibrosis and glutathione-S-transferase placental form (GST-P) positive pre-neoplastic lesions. The combined treatment with both agents exerted more inhibitory effects as compared with either a single agent along with suppression of the activated hepatic stellate cells (Ac-HSC) and neovascularization, both of which play important roles in these processes. Our in vitro study showed that AT-II type 1 receptor blocker (ARB) and SAB inhibited Ac-HSC proliferation and in vitro angiogenesis along with suppression of the in vivo studies. CONCLUSION: Dual blockade of AT-II and Ald suppresses the progression of a non-diabetic rat model of steatohepatitis. Because both agents are widely and safely used in clinical practice, this combination therapy could be an effective new strategy against steatohepatitis in the future.

3.
World J Gastrointest Oncol ; 4(5): 115-8, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22645635

RESUMO

Sorafenib, a multikinase inhibitor, is the first and only drug, which improves significantly the overall survival in patients with advanced hepatocellular carcinoma (HCC). However, many patients experience diverse side effects, some of them severe and unexpected. To date, acute acalculous cholecystitis has not been documented in association with a HCC patient treated with sorafenib. Here, we report the case of a 43-year-old woman with hepatitis C virus-related advanced HCC. She received sorafenib, and later complained of a sudden onset of severe right hypocondrial pain with rebound tenderness and muscle defense. Laboratory examination showed mild elevation of transaminases, biliary enzymes, bilirubin, inflammation markers, and a marked peripheral eosinophilia. Abdominal computed tomography (CT) revealed a swollen gallbladder with exudate associated with severe inflammation without stones or debris. Consequently, sorafenib treatment was stopped immediately, and steroid-pulse therapy was performed. Steroid therapy drastically improved all clinical manifestations along with normalization of CT findings, eosinophilia, and liver functions. In summary, we herein report a rare case of acute severe acalculous cholecystitis associated with sorafenib in the patient with advanced HCC.

4.
Mol Med Rep ; 5(2): 539-44, 2012 02.
Artigo em Inglês | MEDLINE | ID: mdl-22089860

RESUMO

An effective therapeutic strategy for suppressing liver fibrosis should improve the overall prognosis of patients with chronic liver diseases. Although enormous efforts are ongoing to develop anti-fibrotic agents, no drugs have yet been approved as anti-fibrotic agents for humans. Insulin resistance (IR) is reportedly involved in the progression of liver fibrosis. The aim of the present study was to evaluate the effect of combination treatment with a clinically used branched-chain amino acid (BCAA) and an angiotensin-converting enzyme inhibitor (ACE-I) on several fibrotic indices in patients with liver cirrhosis under the condition of IR. BCAA granules (Livact; 12 g/day) and/or ACE-I (perindopril; 4 mg/day) were administered, and several indices were analyzed. A 48-month follow-up revealed that the combination treatment with BCAA and ACE-I markedly improved the progression of serum fibrosis markers, whereas single treatment with either BCAA or ACE-I did not exert these inhibitory effects. The plasma level of transforming growth factor-ß was significantly attenuated almost in parallel with the suppression of serum fibrosis markers. Furthermore, the combined treatment with BCAA and ACE-I improved the serum albumin level and IR, which was evaluated using the homeostasis model assessment method for IR. Taken together, since both BCAA and ACE-I are widely used with safety in clinical practice, these results indicate that this combination therapy may represent a potential new future strategy against liver fibrosis development in patients with liver cirrhosis under the condition of IR.


Assuntos
Aminoácidos de Cadeia Ramificada/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Colágeno Tipo IV/sangue , Quimioterapia Combinada , Feminino , Humanos , Ácido Hialurônico/sangue , Resistência à Insulina , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Perindopril/uso terapêutico , Fator de Crescimento Transformador beta/metabolismo , Resultado do Tratamento
5.
World J Hepatol ; 3(10): 271-4, 2011 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-22059111

RESUMO

Sarcoidosis is a chronic multi-systemic granulomatous disease, and liver involvement frequently occurs. in most cases, no evidence of liver dysfunction is observed, and portal hypertension due to sarcoid liver diseases is a rareoccurrence. Moreover, no case of liver sarcoidosis has ever been reported with confirmation of the disease progression. Herein we describe a patient having hepatic sarcoidosis with severe portal hypertension and liver dysfunction. The diagnosis was histologically confirmed from granulomatous status to established liver cirrhosis over 10 years. A 46-year-old woman developed massive hematemesis due to the rupture of gastric cardial varices. She underwent emergency endoscopic injection sclerotherapy, and clear evidence of chronic hepatic failure. Twelve years ago, she was diagnosed as having sarcoidosis with respiratory clinicalsymptoms. Liver biopsy revealed asymptomatic incidental granulomas without fibrosis development. After a couple of years, features of liver dysfunction were manifest and progressed. Ten years after the first biopsy, a second liver biopsy was performed, and well established dense fibrosis was revealed. Although significant liver dysfunction with portal hypertension is rarely seen in sarcoidosis, this case indicates that we have to consider the possibility that sarcoidosis may cause end-stage liver cirrhosis.

6.
Oncol Rep ; 26(6): 1547-53, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21874260

RESUMO

Insulin resistance (IR) is reportedly involved in the progression of hepatocellular carcinoma (HCC). Since neovascularization plays an important role in hepatocarcinogenesis and IR, an angiostatic therapy may be considered as one of the promising approaches for chemoprevention against HCC. The aim of the current study was to examine the combination effect of a clinically used branched-chain amino acid (BCAA) and an angiotensin-converting enzyme inhibitor (ACE-I), both reportedly possess anti-angiogenic and IR-improving activities, on the cumulative recurrence after curative therapy. BCAA granules (Livact; 12 g/day) and/or ACE-I (perindopril; 4 mg/day) were administered after the curative therapy for HCC, and several indices were analyzed. A 48-month follow-up revealed that the combination treatment with BCAA and ACE-I markedly inhibited the cumulative recurrence of HCC under IR conditions, whereas neither single treatment exerted a significant inhibition. The soluble form of the vascular endothelial growth factor (VEGF; a central angiogenic factor) receptor-2 (sVEGFR2) was significantly decreased only three months after the treatment without recurrence. We also observed that IR, determined by the homeostasis model assessment (HOMA-IR), was significantly improved by this regimen, indicating that an inhibitory effect was achieved, at least partly, by coordinated effects of anti-angiogenesis and IR improvement. In conclusion, since both BCAA and ACE-I are widely used in clinical practice with safety, this combination therapy may represent a potential new strategy for chemoprevention against IR-based HCC recurrence in the future. Moreover, sVEGFR2 may become a useful clinical predictive marker of this combination treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Idoso , Aminoácidos de Cadeia Ramificada/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Resistência à Insulina , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Perindopril/administração & dosagem , Resultado do Tratamento
7.
Int J Mol Med ; 28(1): 81-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21455560

RESUMO

An effective therapeutic strategy for suppressing liver fibrosis development should improve the overall prognosis of patients with chronic liver diseases. Despite efforts to develop anti-fibrotic agents, no drugs have yet been approved as anti-fibrotic treatments for humans. An alternative strategy may be to employ a clinically available agent that also exhibits anti-fibrotic activities, for which the safety of long-term administration has been proven. The aim of the current study was to elucidate the combined effect of clinically used interferon (IFN), ribavirin (Rib) and angiotensin-II receptor blocker (ARB) on liver fibrosis development in mice. A model of CCl4-induced hepatic fibrosis was used to assess the effect of IFN, Rib and ARB. IFN, Rib and ARB were administered after a two-week treatment with CCl4, and the hepatic indices of fibrosis were assessed at eight weeks. Single treatment with IFN, Rib or ARB at the clinically available comparable doses significantly attenuated the liver fibrogenesis associated with the suppression of the number of α-smooth muscle actin positive cells, and the hepatic transforming growth factor-ß (TGF-ß) mRNA. Hepatic neovascularization, which is also known to play a pivotal role in liver fibrogenesis, and vascular endothelial growth factor (VEGF), a potent angiogenic factor, were also markedly inhibited. Combination treatment with any two agents exerted a more potent inhibitory effect than any single treatment. Moreover, the triple cocktail treatment revealed further suppressive effects than any two agent combination. Furthermore, in vitro studies showed that similar combined effects were observed on the proliferation and TGF-ß mRNA expression of activated hepatic stellate cells and endothelial cell tube formation. These results indicate that the cocktail combination treatment of clinically used IFN, Rib and ARB may provide a new strategy for anti-liver fibrosis therapy.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Interferons/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Ribavirina/uso terapêutico , Animais , Modelos Animais de Doenças , Quimioterapia Combinada , Células Estreladas do Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Am J Physiol Gastrointest Liver Physiol ; 300(6): G1094-104, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21372165

RESUMO

Angiotensin II type I receptor blocker and iron chelator reportedly exert suppressive effects on nonalcoholic steatohepatitis (NASH) progression, including liver fibrosis and hepatocarcinogenesis. The aim of this study was to elucidate the combined effect of losartan (LOS), an angiotensin II type I receptor blocker, and deferasirox (DSX), a newly developed oral iron chelator, on the progression of NASH in rats. To induce NASH, F344 rats were fed a choline-deficient l-amino acid-defined diet for 12 wk, and the effects of LOS and DSX at clinically comparable low doses were elucidated in conjunction with oxidative stress, neovascularization, and hepatic stellate cells (HSC) activation, all known to play important roles in the progression of NASH. Treatment with both LOS and DSX suppressed choline-deficient L-amino acid-defined diet-induced liver fibrosis development and hepatocarcinogenesis. This combination treatment exerted a stronger inhibitory effect compared with treatment with a single agent. These inhibitory effects occurred almost concurrently with the suppression of oxidative stress, neovascularization, and HSC activation. Our in vitro study demonstrated that LOS and DSX inhibited angiotensin II-induced proliferation, transforming growth factor-ß(1) expression of activated HSC, and in vitro angiogenesis. These results indicated that dual inhibition by combined treatment of LOS and DSX attenuated the progression of NASH. Since both agents are widely used in clinical practice, this combination therapy may represent a potential new strategy against NASH in the near future.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Benzoatos/administração & dosagem , Carcinoma Hepatocelular/prevenção & controle , Quelantes de Ferro/administração & dosagem , Cirrose Hepática Experimental/prevenção & controle , Neoplasias Hepáticas Experimentais/prevenção & controle , Losartan/administração & dosagem , Triazóis/administração & dosagem , Administração Oral , Inibidores da Angiogênese/administração & dosagem , Angiotensina II/metabolismo , Animais , Antioxidantes/administração & dosagem , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Deficiência de Colina/complicações , Deferasirox , Progressão da Doença , Quimioterapia Combinada , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/etiologia , Cirrose Hepática Experimental/metabolismo , Neoplasias Hepáticas Experimentais/etiologia , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Neovascularização Patológica/etiologia , Neovascularização Patológica/prevenção & controle , Hepatopatia Gordurosa não Alcoólica , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Fatores de Tempo , Fator de Crescimento Transformador beta1/metabolismo
9.
Curr Cancer Drug Targets ; 11(4): 431-41, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21395547

RESUMO

Angiogenesis is a complex and critical process essential for supporting the growth of hepatocellular carcinoma (HCC) as well as hepatocarcinogenesis. Recent studies have revealed that renin-angiotensin system (RAS) is involved in many types of cancer including HCC. Some studies have proven that suppression of angiotensin-II (AT-II) by a clinically used angiotensin-converting enzyme inhibitor (ACE-I) significantly attenuated the HCC growth and hepatocarcinogenesis along with down-regulation of a potent angiogenic factor; namely, the vascular endothelial growth factor (VEGF). When used in combination with the clinical available drugs such as interferon (IFN) and vitamin K (VK), ACE-I exerted more potent anti-tumor activities as compared with either single agent in addition to suppression of the intra-tumoral angiogenesis both in experimental models and clinical practice. It is well known that AT-II plays an important role in the insulin resistance (IR), and IR is reportedly involved in the progression of HCC. The combination of ACE-I and branched-chain amino acids (BCAA) exerted a marked chemopreventive effect against HCC under the condition of IR. In addition to AT-II, aldosterone (Ald), which plays a role in the downstream of AT-II, is also involved in the HCC development, and a clinically used selective Ald blocker (SAB) significantly suppressed the HCC growth and hepatocarcinogenesis. Since ACE-I, IFN, VK, BCAA, and SAB are already in widespread clinical use without any serious adverse effects, they may represent a potential new strategy for cancer therapy and chemoprevention against HCC especially in combination with other angiostatic agents.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Sistema Renina-Angiotensina/fisiologia , Angiotensina II/antagonistas & inibidores , Angiotensina II/metabolismo , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Humanos , Sistema Renina-Angiotensina/efeitos dos fármacos
10.
J Med Case Rep ; 5: 124, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21447168

RESUMO

INTRODUCTION: Budd-Chiari syndrome is a very rare pathological entity that ultimately leads to liver failure. Several therapeutic modalities, including percutaneous transluminal angioplasty, have been attempted to save the life of patients with Budd-Chiari syndrome. Few reports have described a salvage living donor liver transplantation performed after percutaneous transluminal angioplasty in a patient with acute Budd-Chiari syndrome. CASE PRESENTATION: A 26-year-old Japanese man developed severe progressive manifestations, such as massive ascites and hematemesis due to rupture of esophageal varices. After making several investigations, we diagnosed the case as Budd-Chiari syndrome. We first performed percutaneous transluminal angioplasty to dilate a short-segment stenosis of his inferior vena cava. The first percutaneous transluminal angioplasty greatly improved the clinical manifestations. However, after a year, re-stenosis was detected, and a second percutaneous transluminal angioplasty failed to open the severe stricture of his inferior vena cava. Since our patient had manifestations of acute liver failure, we decided to perform salvage living donor liver transplantation from his brother. The transplantation was successfully performed and all clinical manifestations were remarkably alleviated. CONCLUSION: In cases of recurrent Budd-Chiari syndrome, the blocked hepatic venous outflow is not always relieved, even with invasive therapies. We have to take into account the possibility of adopting alternative salvage therapies if the first therapeutic modalities fail. When invasive therapy such as percutaneous transluminal angioplasty fails, liver transplantation should be considered as an alternative option.

11.
Oncol Lett ; 2(1): 69-73, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22870131

RESUMO

The identification of biomarkers of anti-angiogenic therapy that predict clinical benefit is of vital importance. We previously reported that a combination treatment with clinically available safe agents, specifically angiotensin-converting enzyme inhibitor (ACE-I) and vitamin K (VK), inhibited the cumulative recurrence of hepatocellular carcinoma (HCC) via suppression of the vascular endothelial growth factor (VEGF). The present study aimed to identify non-invasive biological markers that predict the clinically beneficial effect of this combination regimen. A combination of ACE-I (perindopril; 4 mg/day) and VK (menatetrenone; 45 mg/day) was administered for 54 months following curative therapy for HCC. The cumulative recurrence and several indices, which are reportedly considered as biological markers of anti-angiogenic therapies, were analyzed. The combined treatment of ACE-I and VK markedly inhibited the cumulative recurrence of HCC during the 54-month follow-up. The serum VEGF and soluble VEGF receptor (sVEGFR)-2 were significantly suppressed with this combination regimen, whereas sVEGFR-1 was not. In HCC patients without recurrence, a significant suppression of VEGF and sVEGFR-2 was achieved within 6 and 3 months after treatment, respectively. In conclusion, the combination treatment of ACE-I and VK is a potentially novel anti-angiogenic strategy for secondary chemoprevention against HCC since the two agents are widely used in clinical practice without serious side effects. Furthermore, sVEGFR-2 may become a useful clinical predictive marker of this combination treatment.

12.
Dig Endosc ; 22(4): 373-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21175502

RESUMO

Clostridium difficile toxin (CD toxin) causes antibiotic-associated colitis, or pseudomembranous colitis (PMC). Although CD toxin is sometimes found in the stools of patients with ulcerative colitis (UC), UC is rarely complicated by PMC. We report herein a case of PMC complicating UC, and present a review of the literature. A 71-year-old woman was diagnosed as having UC of the left colon, and treated with prednisolone and mesalazine. Later, however, lumbar spinal stenosis was also detected. After surgery for lumbar spinal stenosis, she suffered postoperative infection of the lumbar region. After 3-week treatment with antibiotics, she developed diarrhea, bloody stools, and abdominal pain. Colonoscopy revealed PMC of the cecum, ascending colon, sigmoid colon, and rectum. Stools were positive for CD toxin. As cefotiam hydrochloride, levofloxacin hydrate (LVFX), and prednisolone were suspected as the causative agents, she was treated with 1.5 g vancomycin (VCM) daily for 2 weeks without ceasing LVFX. Her symptoms improved, and colonoscopy confirmed resolution of PMC. The possibility of PMC should be considered in UC patients treated with antibiotics, immunosuppressive agents or corticosteroids who complain of gastrointestinal symptoms. These patients should be thoroughly investigated by several modalities, including colonoscopy and CD toxin testing.


Assuntos
Colite Ulcerativa/microbiologia , Enterocolite Pseudomembranosa/microbiologia , Idoso , Antibacterianos/uso terapêutico , Clostridioides difficile , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Colonoscopia , Enterocolite Pseudomembranosa/diagnóstico , Enterocolite Pseudomembranosa/tratamento farmacológico , Feminino , Humanos , Levofloxacino , Ofloxacino/uso terapêutico , Tomografia Computadorizada por Raios X
13.
J Angiogenes Res ; 2: 16, 2010 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-20731881

RESUMO

Although administration of the vascular endothelial growth factor (VEGF), a potent angiogenic factor, could improve the overall survival of destroyed sinusoidal endothelial cells (SEC) in chemically induced murine acute hepatic failure (AHF), the mechanistic roles of the VEGF receptors have not been elucidated yet. The respective roles of VEGF receptors; namely, Flt-1 (VEGFR-1: R1) and KDR/Flk-1 (VEGFR-2: R2), in the D-galactosamine (Gal-N) and lipopolysaccharide (LPS)-induced AHF were elucidated with specific neutralizing monoclonal antibody against R1 and R2 (R1-mAb and R2-mAb, respectively). The serum ALT elevation, with a peak at 24 h after Gal-N+LPS intoxication, was markedly augmented by means of the R1-mAb and R2-mAb. The aggregative effect of R2-mAb was more potent than that of R1-mAb, and the survival rate was 70% in the R2-mAb-treated group and 100% in the other groups. The results of SEC destruction were almost parallel to those of the ALT changes. Our in-vitro study showed that R1-mAb and R2-mAb significantly worsened the Gal-N+LPS-induced cytotoxicity and apoptosis of SEC mediated by caspase-3, which were almost of similar magnitude to those in the in-vivo study. In conclusion, these results indicated that R2 is a major regulator of the salvage effect of VEGF on the maintenance of SEC architecture and the anti-apoptotic effects against chemically-induced murine AHF.

14.
Int J Mol Med ; 26(3): 407-13, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20664958

RESUMO

Although non-alcoholic steatohepatitis (NASH) may progress to cirrhosis and hepatocellular carcinoma (HCC), no effective therapeutic modalities have been fully established yet. Recent studies have shown that the renin-angiotensin-aldosterone-system plays an important role in NASH. The aim of our current study was to elucidate the effects of aldosterone (Ald) inhibition on the progression of NASH. In the choline-deficient L-amino acid-defined diet-induced rat NASH model, the effects of a clinically used selective Ald blocker (SAB) were elucidated in conjunction with the activated hepatic stellate cells (HSC) and neovascularization, which are both known to play important roles in liver fibrosis development and hepatocarcinogenesis, respectively. Liver fibrosis development and the glutathione-S-transferase placental form-positive pre-neoplastic lesions were both markedly attenuated by SAB along with the suppression of the activated HSC and neovascularization. SAB inhibited the hepatic expression of transforming growth factor-beta 1 and also that of the vascular endothelial growth factor. Our in vitro study showed that SAB also inhibited the Ald-induced HSC proliferation and in vitro angiogenesis in a dose-dependent manner. These results indicated that Ald plays a pivotal role in the progression of NASH. Considering that SAB is already widely used in clinical practice, this drug could represent a potential new strategy against NASH in the future.


Assuntos
Aldosterona/química , Aldosterona/metabolismo , Fígado Gorduroso/tratamento farmacológico , Animais , Progressão da Doença , Fígado Gorduroso/patologia , Fígado Gorduroso/fisiopatologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Ratos , Ratos Endogâmicos F344 , Sistema Renina-Angiotensina/fisiologia
15.
Hepatol Res ; 40(5): 540-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20412330

RESUMO

AIM: The renin-angiotensin-aldosterone system (RAAS) has become known as a prerequisite for tumor angiogenesis, including hepatocellular carcinoma (HCC). Although angiotensin II is known to play an important role in tumor growth and angiogenesis, the role of aldosterone (Ald) is still obscure. The aim of our current study was to elucidate the effect of eplerenone, a clinically used selective Ald blocker (SAB), on murine HCC development especially in conjunction with angiogenesis. METHODS: To create an allograft model, we injected 1 x 10(6) of BNL-HCC cells into the flanks of BALB/c mice. After the tumor was established, SAB was administrated at dose of 100 mg/kg per day. RESULTS: Administration of SAB significantly suppressed HCC development along with inhibition of angiogenesis and expression of the vascular endothelial growth factor (VEGF), a potent angiogenic factor. SAB treatment resulted in a marked increase of apoptosis in the tumor, whereas tumor cell proliferation was not altered. Our in vitro study showed that SAB significantly suppressed the Ald-induced endothelial proliferation and tubular formation through inhibition of phosphorylation of the extracellular signal-regulated kinase 1/2. On the contrary, neither Ald nor SAB affected the proliferation of HCC cells in vitro. CONCLUSION: Ald plays a pivotal role in HCC development through VEGF-mediated tumor angiogenesis, and SAB may be a potential new strategy in HCC therapy in the future.

16.
J Gastroenterol ; 45(4): 443-50, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19941011

RESUMO

BACKGROUND: Insulin resistance (IR) is reportedly involved in the progression of hepatocellular carcinoma (HCC). Because neovascularization plays an important role in HCC, including hepatocarcinogenesis, an angiostatic therapy would be a promising approach for chemoprevention against HCC. The aim of the present study was to examine the combined effect of clinically used branched-chain amino acids (BCAAs) and an angiotensin-converting enzyme inhibitor (ACE-I), in conjunction with neovascularization, on hepatocarcinogenesis under the condition of IR. METHODS: The combined effect of the treatment on the development of liver enzyme-altered preneoplastic lesions, angiogenesis, and several indices was elucidated in obese diabetic rats. We also performed several sets of in vitro experiments to examine the mechanisms involved. RESULTS: When used individually, both BCAAs and ACE-I at clinically comparable low doses significantly attenuated the development of preneoplastic lesions, along with the suppression of both angiogenesis and vascular endothelial growth factor (VEGF) expression. The combination treatment with both agents exerted a more potent inhibitory effect than that of either single agent. Our in vitro study showed a similar combined effect on endothelial cell tubule formation. CONCLUSION: This combination regimen showed a marked chemopreventive effect against hepatocarcinogenesis, along with suppression of neovascularization and VEGF expression, in obese diabetic rats. Because both BCAAs and ACE-Is are widely used in clinical practice, this combination therapy may represent a potential new strategy for chemoprevention against IR-based HCC in the future.


Assuntos
Aminoácidos de Cadeia Ramificada/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Resistência à Insulina , Neovascularização Patológica/tratamento farmacológico , Animais , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/prevenção & controle , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Quimioterapia Combinada , Regulação da Expressão Gênica/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/etiologia , Neoplasias Hepáticas Experimentais/prevenção & controle , Masculino , Neovascularização Patológica/etiologia , Obesidade/complicações , Ratos , Ratos Endogâmicos OLETF , Fator A de Crescimento do Endotélio Vascular/genética
17.
World J Gastroenterol ; 15(41): 5193-9, 2009 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-19891019

RESUMO

AIM: To elucidate the possible crosstalk between angiogenesis, cytokeratin-18 (CK-18), and insulin resistance (IR) especially in patients with non-alcoholic steatohepatitis (NASH). METHODS: Twenty-eight patients with NASH and 11 with simple fatty liver disease (FL) were enrolled in this study and underwent clinicopathological examination. The measures of angiogenesis, CK-18, and IR employed were CD34-immunopositive vessels, CK-18-immunopositive cells, and homeostasis model assessment of IR (HOMA-IR), respectively. The correlations of these factors with NASH were elucidated. RESULTS: Significant development of hepatic neovascularization was observed only in NASH, whereas almost no neovascularization could be observed in FL and healthy liver. The degree of angiogenesis was almost parallel to liver fibrosis development, and both parameters were positively correlated. Similarly, CK-18 expression and HOMA-R were significantly increased in NASH as compared with FL and healthy liver. Furthermore, CK-18 and HOMA-IR were also positively correlated with the degree of neovascularization. CONCLUSION: These results indicate that the crosstalk between angiogenesis, CK-18, and IR may play an important role in the onset and progression of NASH.


Assuntos
Progressão da Doença , Fígado Gorduroso/fisiopatologia , Resistência à Insulina/fisiologia , Queratina-18/fisiologia , Neovascularização Patológica/fisiopatologia , Transdução de Sinais/fisiologia , Adulto , Estudos de Casos e Controles , Fígado Gorduroso/etiologia , Feminino , Homeostase/fisiologia , Humanos , Fígado/irrigação sanguínea , Fígado/fisiopatologia , Masculino , Pessoa de Meia-Idade
18.
Oncol Rep ; 22(2): 355-60, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19578777

RESUMO

Pancreatic cancer is one of the leading causes of cancer death, and represents a challenging chemotherapeutic problem. The crucial role of angiogenesis in tumor growth has been widely recognized, and several reports have revealed that the combination treatment of the conventional chemotherapeutic drugs and anti-angiogenic agents exerted synergistic anti-cancerous effects. It has been reported that the clinically used angiotensin type-1 receptor blocker (ARB) exerted potent anti-angiogenic activity. The aim of our current study was to examine the combination effect of gemcitabine (GEM), a widely used conventional chemotherapeutic drug against pancreas cancer, and losartan (Lo), an ARB, on murine pancreatic tumor growth, especially in conjunction with angiogenesis. When used individually, GEM and Lo at clinically comparable low doses moderately suppressed pancreatic tumor development. The combination treatment with GEM and Lo exerted a marked inhibitory effect as compared with single agent treatments even after the tumor was fully established. Neovascularization and the expression of the vascular endothelial growth factor (VEGF), a central angiogenic factor, in the tumor were both markedly suppressed in a magnitude similar to the inhibitory effects against the tumor growth. Since both agents are widely used in the clinical practice, the combination regimen of GEM and Lo may represent a potential new therapeutic strategy for pancreatic cancer in the future.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Desoxicitidina/análogos & derivados , Losartan/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Desoxicitidina/administração & dosagem , Desoxicitidina/uso terapêutico , Sinergismo Farmacológico , Losartan/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/tratamento farmacológico , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/química , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Fator A de Crescimento do Endotélio Vascular/análise , Gencitabina
19.
J Hepatol ; 51(2): 315-21, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19501932

RESUMO

BACKGROUND/AIMS: No chemopreventive agent has been approved against hepatocellular carcinoma (HCC) yet. Since neovascularization plays a pivotal role in HCC, an angiostatic agent is considered as one of the promising approaches. The aim of this study was to elucidate the combined effect of the clinically used vitamin K(2) (VK) and angiotensin-converting enzyme inhibitor (ACE-I) on cumulative recurrence after curative treatment on a total of 87 patients, especially in consideration of neovascularization. METHODS: VK (menatetrenone; 45 mg/day) and/or ACE-I (perindopril; 4 mg/day) were administered for 36-48 months after curative therapy for HCC. The cumulative recurrence and several indices were analyzed. RESULTS: A 48-month follow-up revealed that the combination treatment with VK and ACE-I markedly inhibited the cumulative recurrence of HCC in association with suppression of the serum level of the vascular endothelial growth factor (VEGF); a central angiogenic factor. The serum level of lectin-reactive alpha-fetoprotein was also suppressed almost in parallel with VEGF. These beneficial effects were not observed with single treatment using VK or ACE-I. CONCLUSIONS: The combination treatment of VK and ACE-I may suppress the cumulative recurrence of HCC after the curative therapy, at least partly through suppression of the VEGF-mediated neovascularization.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Recidiva Local de Neoplasia/prevenção & controle , Perindopril/administração & dosagem , Vitamina K 2/análogos & derivados , Idoso , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/terapia , Ablação por Cateter , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/irrigação sanguínea , Neovascularização Patológica/prevenção & controle , Taxa de Sobrevida , Fator A de Crescimento do Endotélio Vascular/sangue , Vitamina K 2/administração & dosagem
20.
BMC Res Notes ; 2: 70, 2009 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-19416517

RESUMO

BACKGROUND: Apart from simple steatosis, the non-alcoholic steatohepatitis (NASH) can progress into liver fibrosis and cirrhosis. To date, however, no widely accepted therapeutic modalities have been established against NASH in the clinical practice. To find out promising new therapeutic agents, it is important to employ an appropriate experimental model of NASH, such as association with insulin resistance. FINDINGS: In the current study, we found that losartan, a clinically used angiotensin-II type 1 receptor blocker, significantly attenuated a choline-deficient L-amino acid-defined (CDAA) diet-induced steatohepatitis in obese diabetic- and insulin resistance-associated Otsuka Long-Evans Tokushima Fatty (OLETF) rats. The transforming growth factor-beta, a well-known major fibrogenic cytokine, was also suppressed in a similar magnitude to that of the fibrosis area. Noteworthy was the finding that these inhibitory effects were achieved even at a clinically comparable low dose. CONCLUSION: Since losartan is widely used without serious side effects in the clinical practice, this agent may be an effective new therapeutic strategy against NASH.

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