Impaired autophagic flux is associated with increased endoplasmic reticulum stress during the development of NAFLD

This work is licensed under a Creative Commons Attribution-NonCommercialNoDerivs 3.0 Unported License.-- et al.The pathogenic mechanisms underlying the progression of non-alcoholic fatty liver disease (NAFLD) are not fully understood. In this study, we aimed to assess the relationship between endoplasmic reticulum (ER) stress and autophagy in human and mouse hepatocytes during NAFLD. ER stress and autophagy markers were analyzed in livers from patients with biopsy-proven non-alcoholic steatosis (NAS) or non-alcoholic steatohepatitis (NASH) compared with livers from subjects with histologically normal liver, in livers from mice fed with chow diet (CHD) compared with mice fed with high fat diet (HFD) or methionine-choline-deficient (MCD) diet and in primary and Huh7 human hepatocytes loaded with palmitic acid (PA). In NASH patients, significant increases in hepatic messenger RNA levels of markers of ER stress (activating transcription factor 4 (ATF4), glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP)) and autophagy (BCN1) were found compared with NAS patients. Likewise, protein levels of GRP78, CHOP and p62/SQSTM1 (p62) autophagic substrate were significantly elevated in NASH compared with NAS patients. In livers from mice fed with HFD or MCD, ER stress-mediated signaling was parallel to the blockade of the autophagic flux assessed by increases in p62, microtubule-associated protein 2 light chain 3 (LC3-II)/LC3-I ratio and accumulation of autophagosomes compared with CHD fed mice. In Huh7 hepatic cells, treatment with PA for 8 h triggered activation of both unfolding protein response and the autophagic flux. Conversely, prolonged treatment with PA (24 h) induced ER stress and cell death together with a blockade of the autophagic flux. Under these conditions, cotreatment with rapamycin or CHOP silencing ameliorated these effects and decreased apoptosis. Our results demonstrated that the autophagic flux is impaired in the liver from both NAFLD patients and murine models of NAFLD, as well as in lipid-overloaded human hepatocytes, and it could be due to elevated ER stress leading to apoptosis. Consequently, therapies aimed to restore the autophagic flux might attenuate or prevent the progression of NAFLD.We acknowledge the following grant support: SAF2012-33283 (MINECO, Spain), Comunidad de Madrid S2010/BMD-2423, EFSD and Amylin Paul Langerhans Grant and Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM, ISCIII, Barcelona, Spain) to AMV.; SAF2010-16037, SAF2013-43713-R (MINECO) and Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD, ISCIII) to PMS. RD12/0042/0019 (ISCIII) and S2010/BMD-2478 (Comunidad de Madrid) to LB, PI 13/01299 and Fundación Mutua Madrileña 2012 to C G-M and AIRC IG-2012 to GMF.Peer Reviewe

Activation of Pregnane X Receptor by Pregnenolone 16 α-carbonitrile Prevents High-Fat Diet-Induced Obesity in AKR/J Mice

Pregnane X receptor (PXR) is known to function as a xenobiotic sensor to regulate xenobiotic metabolism through selective transcription of genes responsible for maintaining physiological homeostasis. Here we report that the activation of PXR by pregnenolone 16α-carbonitrile (PCN) in AKR/J mice can prevent the development of high-fat diet-induced obesity and insulin resistance. The beneficial effects of PCN treatment are seen with reduced lipogenesis and gluconeogenesis in the liver, and lack of hepatic accumulation of lipid and lipid storage in the adipose tissues. RT-PCR analysis of genes involved in gluconeogenesis, lipid metabolism and energy homeostasis reveal that PCN treatment on high-fat diet-fed mice reduces expression in the liver of G6Pase, Pepck, Cyp7a1, Cd36, L-Fabp, Srebp, and Fas genes and slightly enhances expression of Cyp27a1 and Abca1 genes. RT-PCR analysis of genes involved in adipocyte differentiation and lipid metabolism in white adipose tissue show that PCN treatment reduces expression of Pparγ2, Acc1, Cd36, but increases expression of Cpt1b and Pparα genes in mice fed with high-fat diet. Similarly, PCN treatment of animals on high-fat diet increases expression in brown adipose tissue of Pparα, Hsl, Cpt1b, and Cd36 genes, but reduces expression of Acc1 and Scd-1 genes. PXR activation by PCN in high-fat diet fed mice also increases expression of genes involved in thermogenesis in brown adipose tissue including Dio2, Pgc-1α, Pgc-1β, Cidea, and Ucp-3. These results verify the important function of PXR in lipid and energy metabolism and suggest that PXR represents a novel therapeutic target for prevention and treatment of obesity and insulin resistance

Exploiting antitumor immunity to overcome relapse and improve remission duration

Cancer survivors often relapse due to evolving drug-resistant clones and repopulating tumor stem cells. Our preclinical study demonstrated that terminal cancer patient’s lymphocytes can be converted from tolerant bystanders in vivo into effective cytotoxic T-lymphocytes in vitro killing patient’s own tumor cells containing drug-resistant clones and tumor stem cells. We designed a clinical trial combining peginterferon α-2b with imatinib for treatment of stage III/IV gastrointestinal stromal tumor (GIST) with the rational that peginterferon α-2b serves as danger signals to promote antitumor immunity while imatinib’s effective tumor killing undermines tumor-induced tolerance and supply tumor-specific antigens in vivo without leukopenia, thus allowing for proper dendritic cell and cytotoxic T-lymphocyte differentiation toward Th1 response. Interim analysis of eight patients demonstrated significant induction of IFN-γ-producing-CD8+, -CD4+, -NK cell, and IFN-γ-producing-tumor-infiltrating-lymphocytes, signifying significant Th1 response and NK cell activation. After a median follow-up of 3.6 years, complete response (CR) + partial response (PR) = 100%, overall survival = 100%, one patient died of unrelated illness while in remission, six of seven evaluable patients are either in continuing PR/CR (5 patients) or have progression-free survival (PFS, 1 patient) exceeding the upper limit of the 95% confidence level of the genotype-specific-PFS of the phase III imatinib-monotherapy (CALGB150105/SWOGS0033), demonstrating highly promising clinical outcomes. The current trial is closed in preparation for a larger future trial. We conclude that combination of targeted therapy and immunotherapy is safe and induced significant Th1 response and NK cell activation and demonstrated highly promising clinical efficacy in GIST, thus warranting development in other tumor types

Eficacia de diferentes pautas de vacunaci\uf3n contra el virus de la Hepatitis B en pacientes en hemodi\ue1lisis: Correlaci\uf3n con quimioquinas del perfil TH1/TH2 y sus receptores

Introducci\uf3n: A pesar de la disponibilidad de vacunas eficaces, la infecci\uf3n por el virus de la hepatitis B sigue siendo un importante problema de salud p\ufablica a nivel mundial. Los pacientes en hemodi\ue1lisis, que representan una poblaci\uf3n con un alto de riesgo de infecci\uf3n por este virus, responden deficientemente a la vacunaci\uf3n anti-hepatitis B. Por todo ello, resulta imprescindible la implementaci\uf3n en estos pacientes de nuevas pautas de vacunaci\uf3n anti-hepatitis B que incluyan el uso de adyuvantes capaces de mejorar la respuesta inmune inducida por la vacuna. Hip\uf3tesis: Se ha demostrado que el interfer\uf3n-a estimula la respuesta inmune humoral y celular tanto in vitro como in vivo, por lo que esta citoquina podr\ueda ser eficaz como adyuvante de la vacuna anti-hepatitis B en pacientes en hemodi\ue1lisis. Objetivos: Evaluar la seguridad y eficacia de la administraci\uf3n de interfer\uf3n-a2b recombinante (IFNa) como adyuvante de la vacunaci\uf3n anti-hepatitis B en pacientes hemodializados no vacunados previamente. Materiales y M\ue9todos: Se estudiaron 64 pacientes que se incluyeron al azar en el grupo A (n=3D34), los cuales recibieron 4 dosis de 40 mg de la vacuna antihepatitis B, o en el grupo B (n=3D30), que recibieron 4 dosis de 40 mg de la vacuna conjuntamente con 4 dosis de 3 millones de unidades de IFNa, siguiendo un esquema de administraci\uf3n a los 0, 1, 2 y 6 meses. Se llev\uf3 a cabo un an\ue1lisis comparativo de la incidencia de efectos adversos, la tasa de seroprotecci\uf3n (t\uedtulo s\ue9rico de anti-HBs =3D 10 UI/L) precoz y al final del periodo de vacunaci\uf3n, las subclases de IgG anti-HBs, las subpoblaciones de linfocitos circulantes Th1/Th2, el patr\uf3n de expresi\uf3n en los linfocitos de sangre perif\ue9rica de receptores de quimioquinas, as\ued como las concentraciones s\ue9ricas de sus ligandos. Los t\uedtulos s\ue9ricos de anti-HBs, las subclases de IgG anti-HBs y las concentraciones s\ue9ricas de quimioquinas se determinaron por enzimoinmunoan\ue1lisis. La evaluaci\uf3n del perfil Th1/Th2, as\ued como del patr\uf3n de expresi\uf3n de receptores de quimioquinas en los linfocitos circulantes de los pacientes incluidos en el estudio se realiz\uf3 por citometr\ueda de flujo. Resultados: Los efectos adversos aparecieron con mayor frecuencia en los pacientes que recibieron IFN, y fueron leves y de corta duraci\uf3n, siendo los m\ue1s frecuentes la fiebre, la astenia y las artromialgias. La tasa de seroprotecci\uf3n precoz, un mes despu\ue9s de la tercera dosis, fue significativamente mayor en los pacientes del grupo B (73,3%) que en los del grupo A (38,2%, p=3D0,005). La tasa de seroprotecci\uf3n al final de la vacunaci\uf3n (un mes y seis meses despu\ue9s de la cuarta dosis) fue mayor en los pacientes del grupo B (84,6% y 68,1%, respectivamente) que en los del grupo A (62% y 59,2%, respectivamente), pero estas diferencias no fueron estad\uedsticamente significativas (p=3D0.061 y 0.519, respectivamente). La IgG1 anti-HBs fue la subclase predominante en los pacientes del grupo B que alcanzaron la seroprotecci\uf3n, mientras que fue la IgG4 la predominante en los pacientes del grupo A que consiguieron la seroprotecci\uf3n. La proporci\uf3n de linfocitos circulantes Th1 disminuy\uf3 significativamente en los vacunados del grupo B que consiguieron la seroprotecci\uf3n precoz (13,3\ub18,3% vs 26,6\ub114,5% basalmente, p=3D0.006), alcanzando valores similares a la de los sujetos sanos (11,6\ub14,7%, p=3D0.483), mientras que permanecieron anormalmente Resumen 19 elevados en los vacunados del grupo A (19,9\ub114,3% vs 24,1\ub112,4% basalmente, p=3D0.534). En los pacientes que alcanzaron la seroprotecci\uf3n precoz, la proporci\uf3n basal de linfocitos circulantes Th2 que expresaban los receptores de quimioquinas CCR3 y CCR4 fue similar en los pacientes de ambos grupos a la de los individuos sanos, mientras que el porcentaje basal de linfocitos circulantes Th1 que expresaban CXCR3 fue significativamente inferior en los pacientes del grupo A (45,37\ub124,75%) y en los del grupo B (36,98\ub118,78%) que en los sujetos sanos (75,54\ub116,22%, p<0,05). En cambio, s\uf3lo en los pacientes del grupo B se observ\uf3 un porcentaje basal de linfocitos circulantes Th1 que expresaban CCR5 significativamente inferior (12,87\ub111,11%) al del grupo control (22,31\ub116,97%, p=3D0,036). Un hallazgo interesante fue que la expresi\uf3n de CXCR3 y CCR5 al inicio del estudio se correlacionaba significativamente con la subpoblaci\uf3n de linfocitos circulantes Th1 s\uf3lo en los pacientes del grupo B que alcanzaron la seroprotecci\uf3n precozmente. Las concentraciones s\ue9ricas basales de las quimioquinas CXCL10/IP-10 y CCL17/TARC eran significativamente m\ue1s altas en los pacientes que en los sujetos sanos, disminuyendo gradualmente durante y despu\ue9s del periodo de vacunaci\uf3n. Finalmente, se realiz\uf3 un an\ue1lisis estad\uedstico multivariado por regresi\uf3n lineal de las variables demogr\ue1ficas, cl\uednicas e inmunol\uf3gicas basales de los pacientes incluidos en este estudio, identificando como factores predictivos independientes de seroprotecci\uf3n precoz el tiempo en insuficiencia renal cr\uf3nica y el porcentaje basal de linfocitos circulantes Th1. Conclusiones: La administraci\uf3n de IFNa conjuntamente con la vacuna antihepatitis B en los pacientes en hemodi\ue1lisis fue segura y aument\uf3 significativamente la tasa de seroprotecci\uf3n precoz mejorando el perfil de las inmunoglobulinas anti-HBs. La proporci\uf3n de linfocitos circulantes Th1 disminuy\uf3 hasta valores normales s\uf3lo en los pacientes que recibieron IFNa y alcanzaron la seroprotecci\uf3n precoz, observando en estos pacientes que la expresi\uf3n de CXCR3 y CCR5 se asociaba significativamente con la poblaci\uf3n de linfocitos Th1. La administraci\uf3n de IFNa como adyuvante de la vacuna anti-hepatitis B no influy\uf3 en la disminuci\uf3n progresiva de las concentraciones s\ue9ricas de las quimioquinas CXCL10/IP-10 y CCL17/TARC que se produjo durante y despu\ue9s de la vacunaci\uf3n. Finalmente, en este estudio se ha comprobado que la probabilidad de alcanzar la seroprotecci\uf3n precoz, independientemente del tipo de vacunaci\uf3n recibida, fue mayor en los pacientes con un menor tiempo en insuficiencia renal cr\uf3nica y un porcentaje basal de linfocitos circulantes Th1 m\ue1s alto

Citoquinas e Infecci\uf3n: Papel de estos mediadores solubles en la respuesta inmunol\uf3gica frente a bacterias

Se realiz\uf3 un estudio descriptivo, monogr\ue1fico - documental con el objeto de elaborar una actualizaci\uf3n de conocimientos sobre el papel de las citoquinas en la respuesta inmunol\uf3gica frente a infecciones bacterianas. La revisi\uf3n incluy\uf3 investigaciones publicadas en revistas indexadas durante el per\uedodo enero 1998 - diciembre 2003, que relacionaron infecci\uf3n - respuesta inmunol\uf3gica - citoquinas. Con la ayuda de buscadores v\ueda Internet (PubMed, Highwire, MedLine, eMedicine, Amedeo y Google) se obtuvieron 104.000 referencias de publicaciones que trataban acerca de citoquinas en infecciones, de las cuales 641 involucraron directamente a las citoquinas en la respuesta inmunol\uf3gica contra infecciones bacterianas. Las publicaciones peri\uf3dicas se seleccionaron de acuerdo a la disponibilidad de la Hemeroteca del Decanato de Medicina de la Universidad Centroccidental Lisandro Alvarado as\ued como, los textos completos de las publicaciones s\uf3lo disponibles v\ueda Internet a trav\ue9s de suscripci\uf3n al servicio Amedeo y MedLine; tambi\ue9n fueron consultados libros de texto de Inmunolog\ueda. Al comparar las diferentes investigaciones se evidenci\uf3 que las citoquinas son objeto de importantes estudios gen\ue9ticos, inmunofisiol\uf3gicos e inmunopatol\uf3gicos. Entre las razones que justifican su estudio est\ue1n: a) ser mol\ue9culas mensajeras del sistema inmunol\uf3gico; b) influir la respuesta inmunol\uf3gica contra pat\uf3genos; c) ayudar a explicar la patog\ue9nesis de infecciones, como por ejemplo, s\uedndrome de shock t\uf3xico; d) servir como indicadores diagn\uf3stico y pron\uf3stico de infecciones, no s\uf3lo bacterianas, sino tambi\ue9n virales, mic\uf3ticas y parasitarias; y e) ser \ufatiles en el desarrollo de terapias efectivas contra infecciones (como por ejemplo, el desarrollo de vacunas). El resultado de este estudio puede incentivar a los investigadores del Estado Lara, inclusive de Venezuela, a plantearse nuevos dise\uf1os experimentales que involucren la determinaci\uf3n de citoquinas en diversos modelos de enfermedades infecciosas, con la finalidad de determinar su comportamiento en nuestro medio

Hepatitis colestásica neonatal: etiología y evolución en pacientes que acuden a la consulta de gastroenterología

Background: Neonatal cholestatic hepatitis is an inflammatory process of the hepatic parenchyma that usually presents with jaundice, acholia/hypocolia and coluria associated with cholestasis, which occurs in the first trimester of life and is associated with various etiologies: structural, infectious, toxic, idiopathic. or metabolic. Objective: To determine the etiology and evolution of patients with neonatal cholestatic hepatitis who attended the Gastroenterology service of the Children's Hospital "J.M de los Ríos" during the period 2017-2022. Patients and Methods: Descriptive, ambispective, observational, cross-sectional study in which patients ranging in age from newborns to 3 months of age with a diagnosis of cholestatic hepatitis were included, for which clinical records were reviewed. Data were analyzed using descriptive statistics, such as mean, median, standard deviation, 95% confidence intervals, absolute frequencies, and percentages. The ANOVA statistical test was applied and it was considered statistically significant when p&lt;0.05. Results: Universe of 130 patients, 50.8% female, 49.2% male. The predominant etiology was structural/anatomical alterations (50.8%), infectious (TORCH) (39.2%), genetic (9.2%) and metabolic (0.8%). 100% of patients with infectious hepatitis progressed to resolution of cholestasis at 46.4±38.8 days. Kasai was performed on 67.4% of patients with biliary tract atresia (4.6 months on average), all with evolution to liver cirrhosis, 49% died from it. Conclusion: Neonatal cholestatic hepatitis is an entity where the etiological diagnosis is usually late, so it is imperative to know its etiology and evolution to avoid progression and complications that can result in the death of patients who suffer from them.Introducción: La hepatitis colestásica neonatal es un proceso inflamatorio del parénquima hepático que suele cursar con ictericia, acolia/hipocolia y coluria asociadas a colestasis, que se presenta en el primer trimestre de vida y asociada a diversas etiologías: estructural, infecciosa, tóxica, idiopática o metabólica. &nbsp;Objetivo: Determinar la etiología y evolución de los pacientes con hepatitis colestásica neonatal que acudieron al servicio de Gastroenterología del Hospital de Niños “J.M de los Ríos” durante el periodo 2017-2022. Pacientes y Método: Estudio descriptivo, ambispectivo, observacional, de corte transversal en el que se incluyeron pacientes en edades comprendidas desde recién nacidos a 3 meses de edad con diagnóstico de hepatitis colestásica, para lo cual se revisaron las historias clínicas. Los datos se analizaron por medio de estadística descriptiva, como la media, mediana, desviación estándar, intervalos de confianza al 95 %, frecuencias absolutas y porcentajes. Se aplicó la prueba estadística de ANOVA y se consideró como estadísticamente significativo cuando p˂0,05. Resultados: Universo de 130 pacientes, 50.8 % femenino, 49.2 % masculino. La etiología predominante fue alteraciones estructurales/anatómicas (50.8 %), infecciosas (TORCH) (39.2 %), genéticas (9.2 %) y metabólicas (0.8 %). El 100 % de los pacientes con hepatitis infecciosa evolucionó hacia resolución de la colestasis a los 46.4 ± 38.8 días.&nbsp; Al 67.4 % de los pacientes con atresia de vías biliares se realizó kasai (4.6 meses promedio), todos con evolución a cirrosis hepática, 49 % fallecieron a causa de la misma. Conclusión: La hepatitis colestásica neonatal es una entidad en donde el diagnóstico etiológico suele ser tardío, por lo que resulta imperativo conocer su etiologìa y evolución para evitar la progresión y complicaciones que pueden resultar en el fallecimiento de los pacientes que las padecen

The pathogen receptor liver and lymph node sinusoidal endotelial cell C-type lectin is expressed in human Kupffer cells and regulated by PU.1

10 páginas, 7 figuras -- PAGS nros. 287-296Human LSECtin (liver and lymph node sinusoidal endothelial cell C-type lectin, CLEC4G) is a C-type lectin encoded within the L-SIGN/DC-SIGN/CD23 gene cluster. LSECtin acts as a pathogen attachment factor for Ebolavirus and the SARS coronavirus, and its expression can be induced by interleukin-4 on monocytes and macrophages. Although reported as a liver and lymph node sinusoidal endothelial cell-specific molecule, LSECtin could be detected in the MUTZ-3 dendritic-like cell line at the messenger RNA (mRNA) and protein level, and immunohistochemistry analysis on human liver revealed its presence in Kupffer cells coexpressing the myeloid marker CD68. The expression of LSECtin in myeloid cells was further corroborated through the analysis of the proximal regulatory region of the human LSECtin gene, whose activity was maximal in LSECtin+ myeloid cells, and which contains a highly conserved PU.1-binding site. PU.1 transactivated the LSECtin regulatory region in collaboration with hematopoietic-restricted transcription factors (Myb, RUNX3), and was found to bind constitutively to the LSECtin proximal promoter. Moreover, knockdown of PU.1 through the use of small interfering RNA led to a decrease in LSECtin mRNA levels in THP-1 and monocyte-derived dendritic cells, thus confirming the involvement of PU.1 in the myeloid expression of the lectin. Conclusion: LSECtin is expressed by liver myeloid cells, and its expression is dependent on the PU.1 transcription factorThe gene cluster at chromosome 19p13.2 includes the genes encoding for the type II C-type lectins DC-SIGN, L-SIGN, CD23, and LSECtin,1–4 all of which contain a single carbohydrate-recognition domain followed by a stalk domain, a transmembrane region, and a cytoplasmic tail containing various internalization motifs. DC-SIGN, L-SIGN, and LSECtin function as endocytic receptors and mediate binding and internalization of clinically relevant viral, bacterial, and fungal pathogens.5, 6 CD23 is expressed on myeloid cells and activated B lymphocytes, where it functions as a low affinity receptor for immunoglobulin E and plays a role in limiting the extent of immunoglobulin E–mediated pathologies.7, 8 DC-SIGN is expressed on myeloid dendritic cells (DCs),1, 9 alternatively activated in vitro macrophages,10 interstitial DCs,11 a subset of CD14+ peripheral blood DCs,12 and macrophages from various tissues,13–15 whereas L-SIGN is exclusively expressed on endothelial cells of the liver, lymph nodes, and placenta.16, 17 Although reported to be exclusively expressed on liver and lymph node sinusoidal endothelial cells,4 LSECtin has been later found to be expressed in ex vivo isolated human peripheral blood and thymic DCs, as well as in DCs and alternatively activated macrophages generated in vitro.5 The carbohydrate specificity of LSECtin has been recently determined,18 and a scavenging function has been proposed because of its ability to recognize glycoproteins with truncated complex and hybrid N-linked glycans terminating in GlcNAcMan. Kupffer cells constitute more than 50% of resident macrophages in the entire body,19 account for 15% of all liver cells, and are an integral part of the hepatic sinusoid together with sinusoidal endothelial cells and Ito cells. Kupffer cells exhibit a strong endocytic activity and actively scavenge plasma proteins and potentially hazardous microorganisms from the blood to maintain tissue homeostasis,20 a function dependent on the large array of scavenger receptors exposed on their cell surface.21 In fact, Kupffer cells mediate the removal of particulate material from the portal circulation.22 The presence of LSECtin in myeloid cell subsets5 prompted us to clarify its cell distribution in liver cells. We report that LSECtin is expressed in human Kupffer cells, where its expression correlates with the presence of the myeloid-restricted CD68 molecule. Moreover, PU.1 binds in vivo to the human LSECtin proximal promoter, and PU.1 protein levels determine the extent of LSECtin messenger RNA (mRNA) expression. Therefore, PU.1 contributes to the myeloid expression of LSECtin, which constitutes a novel addition to the arsenal of scavenging molecules expressed by liver Kupffer cells. DC, dendritic cell; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; IL-4, interleukin-4; LSECtin, liver and lymph node sinusoidal endothelial cell C-type lectin; MDDC, monocyte-derived dendritic cell; mRNA, messenger RNA; PCR, polymerase chain reaction; PPARγ, peroxisome proliferator-activated receptor gamma; RT-PCR, reverse-transcription polymerase chain reaction; siRNA, small interfering RNASupported by the Ministerio de Educacio´n y Ciencia (grants SAF2005-0021 and GEN2003-20649-C06-01/NAC), Ministerio de Sanidad y Consumo, Instituto de Salud Carlos III (Spanish Network for Research in Infectious Diseases, REIPI RD06/0008/00012 and Red de SIDA RD06/0006/1016), Fundación para la Investigación y Prevención del SIDA en Espan˜a (FIPSE 36663/07), and Fundación Mutua Madrileña (to A. L. C.), and SAF2006-03191 (to J. C.). A. D. S. was supported by an FPI predoctoral grant (BES2004-4405) from Ministerio de Educación y Ciencia, Spain. CIBEREHD is funded by Instituto de Salud Carlos IIIPeer reviewe

The anti-fibrotic effect of liver growth factor is associated with decreased intrahepatic levels of matrix metalloproteinases 2 and 9 and transforming growth factor beta 1 in bile duct-ligated rats

Liver growth factor (LGF), a mitogen for liver cells, behaves as an anti-fibrotic agent even in extrahepatic sites, but its mechanistic basis is unknown. We aimed to determine the intrahepatic expression pattern of key modulators of liver fibrosis in bile ductligated rats (BDL) after injection of LGF. BDL rats received either LGF (4.5 μg/ratXdose, two doses/week, at time 0 or 2 or 5w after operation, depending on the group (BDL+LGF groups, n=20) or saline (BDL+S groups, n=20). Groups were compared in terms of fibrosis (histomorphometry), liver function (aminopyrine breath test), matrix metalloproteinases MMP-2 and MMP-9, transforming growth factor beta 1 (TGF-ß1) and liver endoglin content (Western blotting), and serum tissue inhibitor of metalloproteinases 1 (TIMP-1) levels (ELISA). In BDL+LGF rats, the fibrotic index was significantly lower at 5w, p=0.006, and at 8w, p=0.04, than in BDL+S rats. Liver function values in BDL+LGF rats were higher than those obtained in BDL+S rats (80% at 5w and 79% at 8w, versus 38% and 29%, p<0.01, taking healthy controls as 100%). Notably, in BDL+LGF rats the intrahepatic expression levels of both MMPs were lower at 2w (MMP-2, p=0.03; MMP-9, p=0.05) and 5w (MMP-2, p=0.05, MMP-9, p=0.04). In addition, the hepatic TGF-ß1 level in BDL+LGF rats was lower at 2w (36%, p=0.008), 5w (50%) and 8wk (37%), whereas intrahepatic endoglin expression remained constant in all BDL rats studied. LGF ameliorates liver fibrosis and improves liver function in BDL rats. The LGF-induced anti-fibrotic effect is associated with a decreased hepatic level of MMP-2, MMP-9 and TGF-ß1 in fibrotic rats

Energy recovery method of damping oscillations of the vehicle suspension

Abstract. The paper analyses the existing methods of energy recovery of vehicle suspension oscillation damping. It reveals the most preferred method in which an electromagnetic device of rotational type with a ball screw gear is used. The influence of the road parameters on the dynamic loads in the drive of an electromechanical generator is etermined by mathematical modellin