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1.
Hepatol Res ; 35(3): 204-14, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16737844

RESUMEN

We conducted a multicenter, randomized, controlled trial to investigate the effect of long-term oral supplementation with branched-chain amino acids (BCAA) on the event-free survival in 622 patients with decompensated cirrhosis. In the present study, the development of liver cancer was analyzed as an endpoint in particular. Subjects received either treatment with BCAA at 12g/day or dietary therapy containing the matched daily energy and protein intake. A Cox regression analysis was carried out to estimate the hazard ratios for different background factors stratified by treatment group. Liver cancer was noted in 89 patients. The risk for liver cancer was significantly higher for males, patients with concurrent diabetes mellitus, patients with an alpha-fetoprotein (AFP) level of 20ng/mL or higher, patients with higher body mass index (BMI), and patients with lower serum albumin levels. When the BCAA group and the diet group were compared for factors that interacted with the treatment arms, the risk for liver cancer was significantly reduced in the BCAA group with a BMI of 25 or higher and with an AFP level of 20ng/mL or higher. Oral supplemental treatment with BCAA may reduce the risk of liver cancer in cirrhotic patients with these specific factors.

2.
J Cell Biochem ; 97(1): 178-87, 2006 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-16173080

RESUMEN

Micromolar concentrations (0.5 approximately 5 microM) of all-trans geranylgeranoic acid (GGA) induced cell death in a guinea pig cell line, 104C1, whereas under the same conditions GGA was unable to kill 104C1/O4C, a clone established from 104C1 cells by transfection of them with the human phospholipid hydroperoxide glutathione peroxidase (PHGPx) gene. GGA (5 microM) induced a loss of the mitochondrial inner membrane potential (DeltaPsim) in 104C1 cells in 2 h, and their apoptotic cell death became evident in 6 h. On the other hand, 104C1/O4C cells were resistant to loss of DeltaPsim and showed intact morphology until at least 24 h after addition of 10 microM GGA. Dihydroethidine, superoxide-sensitive probe, was immediately oxidized 15 min after addition of GGA in both 104C1 and 104C1/O4C cells. The peroxide-sensitive probe 2',7'-dichlorofluorescin diacetate (H2-DCF-DA) was strongly oxidized in 104C1 cells 4 h after the addition of 2.5 microM GGA, but not in 104C1/O4C cells even in the presence of 10 microM GGA. The present results suggest that GGA induced a hyper-production of superoxide and subsequently peroxides, which in turn may have led to dissipation of the DeltaPsim and final apoptotic cell death in 104C1 cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Diterpenos/farmacología , Glutatión Peroxidasa/genética , Animales , Cobayas , Microscopía Fluorescente , Fosfolípido Hidroperóxido Glutatión Peroxidasa
3.
Clin Gastroenterol Hepatol ; 3(7): 705-13, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16206505

RESUMEN

BACKGROUND & AIMS: Nutritional intervention with branched-chain amino acid (BCAA) is reported to increase serum albumin concentration in patients with decompensated cirrhosis. However, a definite conclusion on whether it can improve patients' survival has not yet been reached. The present study aimed to test possibilities of improving survival of patients with decompensated cirrhosis by using a BCAA preparation that is suitable for long-term oral administration. METHODS: A multicenter, randomized, and nutrient intake-controlled trial on the comparative effects of BCAA orally administered at 12 g/day for 2 years versus diet therapy with defined daily food intake (1.0-1.4 g protein kg(-1) day(-1) including BCAA preparation and 25-35 kcal kg(-1) day(-1)) was conducted in 646 patients with decompensated cirrhosis. The primary end point was a composite of death by any cause, development of liver cancer, rupture of esophageal varices, or progress of hepatic failure (event-free survival). The secondary end points were serum albumin concentration and health-related quality of life (QOL) measured by Short Form-36 questionnaire. RESULTS: The incidence of events comprising the primary end point significantly decreased in the BCAA group as compared with the diet group (hazard ratio, 0.67; 95% confidence interval, 0.49-0.93; P = .015; median observation period, 445 days). Serum albumin concentration increased significantly in the BCAA group as compared with the diet group (P = .018). The "general health perception" domain in Short Form-36 measures was also improved (P = .003). Patients' adherence to the prescription was favorable. CONCLUSIONS: Oral supplementation with a BCAA preparation that can be administered for a long period improves event-free survival, serum albumin concentration, and QOL in patients with decompensated cirrhosis with an adequate daily food intake.


Asunto(s)
Aminoácidos de Cadena Ramificada/administración & dosificación , Suplementos Dietéticos , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/mortalidad , Administración Oral , Adulto , Anciano , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Humanos , Japón , Cirrosis Hepática/complicaciones , Fallo Hepático/etiología , Fallo Hepático/prevención & control , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/prevención & control , Masculino , Persona de Mediana Edad
4.
Liver Int ; 25(5): 1010-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16162161

RESUMEN

BACKGROUND/AIM: As biotechnology continues to advance, a bioartificial liver is expected to be developed for the treatment of patients with fulminant hepatic failure (FHF) whose liver dysfunction is potentially reversible or for providing liver support as a bridge to liver transplantation. While monolayer-cultured hepatocytes rapidly lose their capacity to express many liver-specific functions over time when cultured, spherical-shaped hepatocytes in three-dimensional culture with the use of extracellular matrix components sustain long-term survival by maintaining differentiated hepatocyte functions. The aim of this study was to investigate whether sufficient functions of viable spherical-shaped hepatocytes could be maintained in plasma of patients with FHF in order to use these cells in an extracorporeal system. METHODS: Hepatocyte functions were evaluated under monolayer or three-dimensional culture in FHF plasma. RESULTS: Primary rat hepatocytes on poly-N-p-vinylbenzyl-D-lactonamide (PVLA) formed spheroids even in FHF plasma and maintained their spherical shapes in FHF plasma as long as in medium. Spherical-shaped hepatocytes on PVLA cultured in FHF plasma showed higher activity in albumin secretion, urea formation, and gluconeogenesis than those in normal human plasma or medium. As being cultured in medium, hepatocytes on PVLA cultured in plasma were also superior to cells on collagen in regard to albumin secretion, amino acid metabolism, and gluconeogenesis. CONCLUSIONS: These findings demonstrated that FHF plasma is not toxic to rat hepatocyte spheroids and that hepatocyte spheroids have potential use in the development of a bioartificial liver.


Asunto(s)
Hepatocitos/fisiología , Fallo Hepático Agudo/sangre , Albúminas/metabolismo , Aminoácidos/metabolismo , Animales , Células Cultivadas , Gluconeogénesis , Masculino , Biosíntesis de Proteínas , Ratas , Ratas Wistar , Urea/metabolismo
5.
Intervirology ; 48(1): 39-45, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15785088

RESUMEN

Oral administration with acyclic retinoid, a synthetic vitamin A analog, for a limited period of 12 months (48 weeks) prevented the development of second primary hepatocellular carcinoma (HCC) and also improved the survival of patients who underwent curative treatments of the initial tumor. Following that randomized controlled study reported in 1996 and 1999, we have continued to follow up the patients by medical imaging and blood chemical analyses, and found that the preventive effect of acyclic retinoid lasted up to 199 weeks after randomization (or 151 weeks after completion of retinoid administration). The retinoid's effect was not mediated by reduction in hepatic necro-inflammation since no significant decrease in serum aminotransferase activity was seen in the retinoid group. Such observation seems quite distinct from the cancer-preventive mechanism of interferon, a potent immunopreventive agent for HCC. We have also shown here the reduction by the retinoid in serum levels of lectin-reactive alpha-fetoprotein (AFP-L3) and protein induced by vitamin K absence or antagonist-II (PIVKA-II), both of which indicate the presence of latent HCC cells. These results suggest that acyclic retinoid may delete such malignant clones before they expand to clinically detectable tumors and thereby inhibited second primary HCC. Once such latent clones are eradicated, it may well take at least several years for the next cancer clone to arise clinically. This may possibly explain a reason for the long-term effect of the retinoid even after the limited period of administration.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/prevención & control , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Primarias Secundarias/prevención & control , Tretinoina/análogos & derivados , Antineoplásicos/farmacología , Aspartato Aminotransferasas/sangre , Biomarcadores/sangre , Humanos , Japón , Neoplasias Hepáticas/prevención & control , Precursores de Proteínas/sangre , Protrombina , Análisis de Supervivencia , Tretinoina/farmacología , Tretinoina/uso terapéutico , alfa-Fetoproteínas/análisis
6.
Hepatol Res ; 31(4): 232-40, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15792640

RESUMEN

This multicenter study compared the effects of branched-chain amino acid granules (Livact((R)) Granules, LIV) and an enteral nutrient for chronic hepatic failure (Aminoleban((R)) EN, EN) on serum albumin in patients with decompensated liver cirrhosis. This study enrolled "patients with decompensated liver cirrhosis associated with hepatic encephalopathy who were suffering from hypoalbuminemia in spite of adequate food intake," a condition for which both drugs are indicated. Enrolled patients were randomized to the two groups according to the central registration method. This study continued for 24 weeks. Selected foods were supplied to each patient in principle so that caloric and protein intakes were standardized between the two groups. A total of 281 patients were enrolled. LIV was not inferior to EN concerning the primary efficacy endpoint changes in serum albumin.

7.
J Gastroenterol ; 39(6): 527-33, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15235869

RESUMEN

BACKGROUND: Although the pathogenesis of osteopenia in Crohn's disease is not established, vitamin D deficiency is thought to be an important risk factor. However, little is known about the prevalence of vitamin D deficiency in patients with Crohn's disease in Japan. This study aimed to clarify the prevalence of vitamin D deficiency in patients with Crohn's disease in Japan and to examine the possible causes of the deficiency. METHODS: We investigated serum 25-hydroxyvitamin D (25-OHD) levels, various laboratory parameters, and patient histories in 33 outpatients (25 men, 8 women; median age, 37 years; range, 26-57 years) and 15 age- and sex-matched healthy controls (8 men, 7 women; median age, 37 years; range, 24-57 years) and assessed risk factors for vitamin D deficiency. RESULTS: Although patients with Crohn's disease did not have significantly lower serum concentrations of 25-OHD than controls, 9 of 33 patients (27.3%) were considered vitamin D deficient (serum 25-OHD level 15 years) and who have been in the active stage of the disease for long periods.


Asunto(s)
Enfermedad de Crohn/epidemiología , Deficiencia de Vitamina D/epidemiología , Vitamina D/análogos & derivados , Adulto , Colitis/sangre , Colitis/epidemiología , Comorbilidad , Enfermedad de Crohn/sangre , Femenino , Ferritinas/sangre , Humanos , Ileítis/sangre , Ileítis/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Vitamina D/sangre
8.
Curr Cancer Drug Targets ; 4(3): 285-98, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15134535

RESUMEN

We review the therapeutic and preventive applications of a retinoid analog (vitamin A and its derivatives) for human cancers. Chemoprevention of cancer is an intervention in the carcinogenic process by chemical agents that block or reverse the malignant transformation of cells. Retinoids are prime candidates for cancer chemoprevention since cancer is characterized by abnormal growth with a lack of differentiation, which could be modified by retinoids. Retinoids exert their biological functions through nuclear receptors, retinoic acid receptor (RAR) and retinoid X receptor (RXR). A number of experimental and clinical studies have been performed in the past two decades with retinoids showing that they inhibit or reverse the carcinogenic process in some organs, including hematological malignancy as well as premalignant and malignant lesions in the oral cavity, head and neck, breast, skin and liver. We particularly focus upon the therapeutic application of all-trans RA (atRA) to acute promyelocytic leukemia (APL) and on the preventive approach to hepatocellular carcinoma (HCC) by a synthetic retinoid analog, acyclic retinoid. In both malignancies, malfunction of retinoid nuclear receptors is closely related to their carcinogenic process. In APL, a chromosomal translocation produces a chimeric protein between RAR alpha and a protein called promyelocyte leukemia protein (PML). PML-RAR alpha works as a dominant negative receptor in the leukemic cells, interfering with the normal function of RAR alpha and/or PML, which in turn results in the arrest of cell maturation at the stage of promyelocytes. Oral administration of atRA induces differentiation of promyelocytic leukemic cells to mature neutrophils, and leads to a high rates (over 90%) of complete remission. AtRA therapy has become standard in the treatment of APL. In the case of HCC, post-translational modification of RXR by phosphorylation impairs its function, which leads to uncontrolled cell growth. Acyclic retinoid suppresses the phosphorylation of RXR alpha, restores its function in the presence of its endogenous ligand, 9-cis RA, and thereby induces apoptosis of the cancer cells. Acyclic retinoid given orally successfully suppresses the development of second primary tumors in cirrhotic patients who undergo curative removal of preceding HCC. Eradication of (pre)malignant clones ('clonal deletion') from the liver is suggested as a mechanism of the chemopreventive effect. Further development of more effective retinoids as well as their use in combination with other classes of anticancer agents including immunopreventive drugs like interferons may provide strategies for cancer prevention.


Asunto(s)
Anticarcinógenos/uso terapéutico , Neoplasias/prevención & control , Retinoides/uso terapéutico , Animales , Humanos , Receptores de Ácido Retinoico/fisiología , Receptores X Retinoide , Retinoides/fisiología , Factores de Transcripción/fisiología
9.
J Hepatol ; 36(5): 660-71, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11983450

RESUMEN

BACKGROUND/AIMS: Acyclic retinoid (AR; all trans-3,7,11,15-tetramethyl-2,4,6,10,14-hexadecapentaenoic acid) prevented hepatocarcinogenesis in animal models and in a randomized clinical trial by eradicating premalignant and latent malignant clones of transformed cells from the liver. We investigated the possible mechanism of this clonal deletion at the cellular level. METHODS: Human hepatoma-derived cell lines, PLC/PRF/5, HuH-7, and JHH-7, were treated in vitro with AR. Secretion of albumin and that of lectin-reactive isoform of alpha-fetoprotein (AFP-L3) were measured as markers of differentiation and dedifferentiation of the cells, respectively. Telomerase reverse transcriptase (TERT) mRNA expression and telomerase activity were measured by reverse transcriptase polymerase chain reaction (RT-PCR) and stretch PCR assay, respectively. Caspase activities were measured by colorimetric protease assay. Mitochondrial membrane permeability transition was examined by Rhodamine staining. RESULTS: Production of albumin was recovered while that of AFP-L3 was reduced after exposure of the cells to 10 microM AR for 2 days. This differentiation was maintained for another 2 days without retinoid. In parallel, both TERT mRNA expression and telomerase activity were down-regulated. The cells subsequently died due to apoptosis after 4-6 experimental days. Serial increases in mitochondrial membrane permeability and caspase-9 and -3 activities induced apoptosis. CONCLUSIONS: AR first induces differentiation and reduces telomerase activity. Subsequent apoptosis may contribute to the eradication of the clone.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Telomerasa/genética , Telomerasa/metabolismo , Tretinoina/análogos & derivados , Tretinoina/farmacología , Alitretinoína , Caspasas/metabolismo , Diferenciación Celular/efectos de los fármacos , Permeabilidad de la Membrana Celular/efectos de los fármacos , Proteínas de Unión al ADN , Regulación hacia Abajo/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Mitocondrias/metabolismo , ARN Mensajero/análisis , Células Tumorales Cultivadas/citología , Células Tumorales Cultivadas/efectos de los fármacos
10.
J Bone Miner Res ; 17(1): 91-100, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11771673

RESUMEN

Retinoids are known to be of special importance for normal bone growth and development. Recently, we reported that retinoids not only induced osteoblast differentiation, but also inhibited osteoclast formation in vitro. In this study, we examined the osteogenic effects of geranylgeranoic acid (GGA), a chemically synthesized acyclic retinoid, in bone in vitro and in vivo. GGA not only suppressed proliferation of osteoblastic MC3T3-E1 cells, but also up-regulated differentiation markers of osteoblasts such as alkaline phosphatase (ALP) activity and expression of osteopontin (OP) messenger RNA (mRNA). In contrast, GGA inhibited osteoclast formation induced by 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] in cocultures of mouse bone marrow cells and primary osteoblasts. Treatment of stromal ST2 cells with GGA restored the 1alpha,25(OH)2D3- or prostaglandin E2 (PGE2)-induced suppression of osteoprotegerin (OPG) mRNA expression. GGA inhibited osteoclast formation induced by macrophage colony-stimulating factor (M-CSF) and soluble receptor activator of nuclear factor kappaB ligand (sRANKL) in the culture of bone marrow macrophages. Thus, it is likely that GGA inhibits osteoclast formation by affecting both osteoblasts and osteoclast progenitors in the coculture system. Furthermore, in vivo, GGA increased bone mineral density (BMD) of total as well as distal femur in a P6 strain of senescence-accelerated mice (SAMP6). These results indicate that GGA increases bone mass by maintaining a positive balance of bone turnover by inducing osteoblast differentiation and suppressing osteoclast formation.


Asunto(s)
Diterpenos/farmacología , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Células 3T3 , Fosfatasa Alcalina/metabolismo , Animales , Secuencia de Bases , Densidad Ósea/efectos de los fármacos , Enfermedades Óseas Metabólicas/genética , Enfermedades Óseas Metabólicas/metabolismo , Enfermedades Óseas Metabólicas/patología , Remodelación Ósea/efectos de los fármacos , Remodelación Ósea/fisiología , Calcitriol/farmacología , Proteínas Portadoras/farmacología , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Técnicas de Cocultivo , Expresión Génica/efectos de los fármacos , Factor Estimulante de Colonias de Macrófagos/farmacología , Masculino , Glicoproteínas de Membrana/farmacología , Ratones , Ratones Mutantes , Técnicas de Cultivo de Órganos , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Osteopontina , Ligando RANK , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptor Activador del Factor Nuclear kappa-B , Sialoglicoproteínas/genética
11.
Front Biosci ; 7: d204-18, 2002 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11779708

RESUMEN

Pathobiological functions and metabolism of retinoids (vitamin A and its derivatives) in liver fibrosis and hepatocellular carcinoma (HCC) are discussed in the present review. Retinoic acid (RA, active metabolite) exacerbates liver fibrosis that is not accompanied by hepatic necroinflammation, in which RA acts directly on hepatic stellate cells (HSCs); RA enhances plasminogen activator/plasmin levels and thereby induces proteolytic activation of latent transforming growth factor-beta (TGF-beta), a strong fibrogenic cytokine, resulting in enhanced collagen production. We have developed a protease inhibitor, camostat mesilate, that suppresses TGF-beta activation and thereby inhibits the transformation of HSCs, leading to reduced matrix production by the cells. The compound is effective not only in preventing but also in reducing hepatic fibrosis in rats when administered orally. HCC is refractory to RA due to its local depletion in the tumors and also due to malfunction of its nuclear receptor, retinoid X receptor-alpha (RXRalpha) Oral supplementation of a synthetic retinoid named acyclic retinoid led to the disappearance of serum lectin-reactive alpha-fetoprotein (AFP-L3) and subsequently suppressed posttherapeutic recurrence of HCC in cirrhotic patients. These results suggest eradication of AFP-L3-producing latent malignant clones from the liver by the retinoid. We propose the concept of "clonal deletion" therapy for cancer chemoprevention, a new category of cancer chemotherapy.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Cirrosis Hepática/inducido químicamente , Neoplasias Hepáticas/tratamiento farmacológico , Retinoides/efectos adversos , Retinoides/uso terapéutico , Animales , Carcinoma Hepatocelular/prevención & control , Humanos , Cirrosis Hepática/prevención & control , Neoplasias Hepáticas/prevención & control , Retinoides/farmacología
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