RESUMO
BACKGROUND: Ferroptosis, which is characterized by lipid peroxidation and iron accumulation, is closely associated with the pathogenesis of acute renal injury (AKI). Cyanidin-3-glucoside (C3G), a typical flavonoid that has anti-inflammatory and antioxidant effects on ischemiaâreperfusion (I/R) injury, can induce AMP-activated protein kinase (AMPK) activation. This study aimed to show that C3G exerts nephroprotective effects against I/R-AKI related ferroptosis by regulating the AMPK pathway. METHODS: Hypoxia/reoxygenation (H/R)-induced HK-2 cells and I/R-AKI mice were treated with C3G with or without inhibiting AMPK. The level of intracellular free iron, the expression of the ferroptosis-related proteins acyl-CoA synthetase long chain family member 4 (ACSL4) and glutathione peroxidase 4 (GPX4), and the levels of the lipid peroxidation markers 4-hydroxynonenal (4-HNE), lipid reactive oxygen species (ROS) and malondialdehyde (MDA) were examined. RESULTS: We observed the inhibitory effect of C3G on ferroptosis in vitro and in vivo, which was characterized by the reversion of excessive intracellular free iron accumulation, a decrease in 4-HNE, lipid ROS, MDA levels and ACSL4 expression, and an increase in GPX4 expression and glutathione (GSH) levels. Notably, the inhibition of AMPK by CC significantly abrogated the nephroprotective effect of C3G on I/R-AKI models in vivo and in vitro. CONCLUSION: Our results provide new insight into the nephroprotective effect of C3G on acute I/R-AKI by inhibiting ferroptosis by activating the AMPK pathway.
Assuntos
Injúria Renal Aguda , Ferroptose , Traumatismo por Reperfusão , Animais , Camundongos , Proteínas Quinases Ativadas por AMP , Espécies Reativas de Oxigênio , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/etiologia , Traumatismo por Reperfusão/tratamento farmacológico , Ferro , Isquemia , LipídeosRESUMO
In the tumor microenvironment (TME), one of the major functions of tumor-recruited CD11b+ cells are the suppression of the T-cell-mediated anti-tumor immune response. ß-glucan could convert the phenotype of tumor-recruited CD11b+ cells from the suppressive to the promotive, and enhanced their anti-tumor effects. However, ß-glucan could enhance the PD-1/PD-L1 expression on CD11b+ cells, while PD-1 could inhibit macrophage phagocytosis and PD-L1 could induce a co-inhibitory signal in T-cells and lead to T-cell apoptosis and anergy. These protumor effects may be reversed by PD-1/PD-L1 block therapy. In the present study, we focused on the efficacy of ß-glucan anti-tumor therapy combined with anti-PD-L1 mAb treatment, and the mechanism of their synergistic effects could be fully verified. We verified the effect of ß-glucan (i.e., inflammatory cytokine secretion of TNF-α, IL-12, IL-6, IL-1ß and the expression of immune checkpoint PD-1/PD-L1) in naïve mouse peritoneal exudate CD11b+ cells. In our mouse melanoma model, treatment with a PD-L1 blocking antibody with ß-glucan synergized tumor regression. After treatment with ß-glucan and anti-PD-L1 mAb antibody, tumor infiltrating leukocyte (TILs) not only showed a competent T-cell function (CD107a, perforin, IL-2, IFN-γ and Ki67) and CTL population, but also showed enhanced tumor-recruited CD11b+ cell activity (IL-12, IL-6, IL-1ß and PD-1). This effect was also verified in the peritoneal exudate CD11b+ cells of tumor-bearing mice. PD-1/PD-L1 blockade therapy enhanced the ß-glucan antitumor effects via the blockade of tumor-recruited CD11b+ cell immune checkpoints in the melanoma model.
Assuntos
Interleucina-6 , Melanoma , Animais , Camundongos , Receptor de Morte Celular Programada 1 , Anticorpos Monoclonais/farmacologia , Interleucina-12/farmacologia , Antígeno B7-H1 , Microambiente Tumoral , Linhagem Celular TumoralRESUMO
Ulcerative colitis (UC) is one of the two main forms of inflammatory bowel disease (IBD) and is an idiopathic, chronic inflammatory disease of the colonic mucosa with an unclear etiology. Interleukin (IL)-10 has been reported to play a crucial role in the maintenance of immune homeostasis in the intestinal environment. Type 1 regulatory T (Tr1) cells are a subset of CD4+Foxp3- T cells able to secrete high amounts of IL-10 with potent immunosuppressive properties. In this study, we found that the combination of anti-GITR antibody (G3c) and CD28 superagonist (D665) treatment stimulated the generation of a large amount of Tr1 cells. Furthermore, G3c/D665 treatment not only significantly relieved severe mucosal damage but also reduced the incidence of colonic shortening, weight loss, and hematochezia. Dextran sodium sulfate (DSS) upregulated the mRNA levels of IL-6, IL-1ß, IL-17, IL-12, tumor necrosis factor-alpha, C-C chemokine receptor type 5, and Bax in splenic lymphocytes (SPLs) and colon tissues, while G3c/D665 treatment conversely inhibited the increase in mRNA levels of these genes. In addition, G3c/D665 treatment altered the proportion of CD4+ and CD8+ T cells and increased CD4+CD25+Foxp3+ regulatory T cells in SPLs, mesenteric lymph nodes (MLNs), and lamina propria lymphocytes (LPLs). Thus, the combination of G3c and D665 treatment showed efficacy against DSS-induced UC in mice by inducing a large amount of Tr1 cell generation via the musculoaponeurotic fibrosarcoma pathways in vivo and relieving inflammatory responses both systematically and locally.
Assuntos
Colite Ulcerativa , Colite , Animais , Antígenos CD28/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colo , Sulfato de Dextrana , Fatores de Transcrição Forkhead/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Sulfatos , Linfócitos T ReguladoresRESUMO
Small-for-size syndrome (SFSS) is a common complication following partial liver transplantation and extended hepatectomy. SFSS is characterized by postoperative liver dysfunction caused by insufficient regenerative capacity and portal hyperperfusion and is more frequent in patients with preexisting liver disease. We explored the effect of the Mesenchymal-epithelial transition factor (MET)-agonistic antibody 71D6 on liver regeneration and functional recovery in a mouse model of SFSS. Male C57/BL6 mice were exposed to repeated carbon tetrachloride injections for 10 weeks and then randomized into 2 arms receiving 3 mg/kg 71D6 or a control immunoglobulin G (IgG). At 2 days after the randomization, the mice were subjected to 70% hepatectomy. Mouse survival was recorded up to 28 days after hepatectomy. Satellite animals were euthanized at different time points to analyze liver regeneration, fibrosis, and inflammation. Serum 71D6 administration significantly decreased mouse mortality consequent to insufficient regeneration of the cirrhotic liver. Analysis of liver specimens in satellite animals revealed that 71D6 promoted powerful activation of the extracellular signal-regulated kinase pathway and accelerated liver regeneration, characterized by increased liver-to-body weight, augmented mitotic index, and higher serum albumin levels. Moreover, 71D6 accelerated the resolution of hepatic fibrosis as measured by picrosirius red, desmin, and α-smooth muscle actin staining, and suppressed liver infiltration by macrophages as measured by CD68 and F4/80 staining. Analysis of gene expression by reverse-transcription polymerase chain reaction confirmed that 71D6 administration suppressed the expression of key profibrotic genes, including platelet-derived growth factor, tissue inhibitor of metalloproteinase 3, and transforming growth factor-ß1, and of key proinflammatory genes, including tumor necrosis factor-α, interleukin-1ß, chemokine (C-C motif) ligand 3, and chemokine (C-C motif) ligand 5. These results suggest that activating the MET pathway via an hepatocyte growth factor-mimetic antibody may be beneficial in patients with SFSS and possibly other types of acute and chronic liver disorders.
Assuntos
Regeneração Hepática , Transplante de Fígado , Animais , Hepatectomia/efeitos adversos , Humanos , Fígado/metabolismo , Cirrose Hepática/patologia , Masculino , CamundongosRESUMO
Mitochondria are key cytoplasmic organelles. Their activation is critical for the generation of T cell proliferation and cytotoxicity. Exhausted tumor-infiltrating T cells show a decreased mitochondrial function and mass. 5-Aminolevulinic acid (5-ALA), a natural amino acid that is only produced in the mitochondria, has been shown to influence metabolic functions. We hypothesized that 5-ALA with sodium ferrous citrate (SFC) might provide metabolic support for tumor-infiltrating T cells. In a mouse melanoma model, we found that 5-ALA/SFC with a programmed cell death-ligand 1 (PD-L1) blocking Ab synergized tumor regression. After treatment with 5-ALA/SFC and anti-PD-L1 Ab, tumor infiltrating lymphocytes (TILs) were not only competent for the production of cytolytic particles and cytokines (granzyme B, interleukin-2, and γ-interferon) but also showed enhanced Ki-67 activity (a proliferation marker). The number of activated T cells (PD-1+ Tim-3- ) was also significantly increased. Furthermore, we found that 5-ALA/SFC activated the mitochondrial functions, including the oxygen consumption rate, ATP level, and complex V expression. The mRNA levels of Nrf-2, HO-1, Sirt-1, and PGC-1α and the protein levels of Sirt-1 were upregulated by treatment with 5-ALA/SFC. Taken together, our findings revealed that 5-ALA/SFC could be a key metabolic regulator in exhausted T cell metabolism and suggested that 5-ALA/SFC might synergize with anti-PD-1/PD-L1 therapy to boost the intratumoral efficacy of tumor-specific T cells. Our study not only revealed a new aspect of immune metabolism, but also paved the way to develop a strategy for combined anti-PD-1/PD-L1 cancer immunotherapy.
Assuntos
Ácido Aminolevulínico/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Ácido Cítrico/farmacologia , Compostos Ferrosos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Terapia Combinada , Feminino , Heme Oxigenase-1/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Antígeno Ki-67/metabolismo , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/citologia , Linfócitos do Interstício Tumoral/metabolismo , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Melanoma Experimental/terapia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Fator 1 Nuclear Respiratório/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 1/metabolismoRESUMO
Nonalcoholic steatohepatitis (NASH) could progress to hepatic fibrosis in the absence of effective control. The purpose of our experiment was to investigate the protective effect of drinking water with a high concentration of hydrogen, namely, hydrogen-rich water (HRW), on mice with nonalcoholic fatty liver disease to elucidate the mechanism underlying the therapeutic action of molecular hydrogen. The choline-supplemented, l-amino acid-defined (CSAA) or the choline-deficient, l-amino acid-defined (CDAA) diet for 20 wk was used to induce NASH and fibrosis in the mice model and simultaneously treated with the high-concentration 7-ppm HRW for different periods (4 wk, 8 wk, and 20 wk). Primary hepatocytes were stimulated by palmitate to mimic liver lipid metabolism during fatty liver formation. Primary hepatocytes were cultured in a closed vessel filled with 21% O2 + 5% CO2 + 3.8% H2 and N2 as the base gas to verify the response of primary hepatocytes in a high concentration of hydrogen gas in vitro. Mice in the CSAA + HRW group had lower serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and milder histological damage. The inflammatory cytokines were expressed at lower levels in the HRW group than in the CSAA group. Importantly, HRW reversed hepatocyte fatty acid oxidation and lipogenesis as well as hepatic inflammation and fibrosis in preexisting hepatic fibrosis specimens. Molecular hydrogen inhibits the lipopolysaccharide-induced production of inflammation cytokines through increasing heme oxygenase-1 (HO-1) expression. Furthermore, HRW improved hepatic steatosis in the CSAA + HRW group. Sirtuin 1 (Sirt1) induction by molecular hydrogen via the HO-1/adenosine monophosphate activated protein kinase (AMPK)/peroxisome proliferator-activated receptor α (PPARα)/peroxisome proliferator-activated receptor γ (PPAR-γ) pathway suppresses palmitate-mediated abnormal fat metabolism. Orally administered HRW suppressed steatosis induced by CSAA and attenuated fibrosis induced by CDAA, possibly by reducing oxidative stress and the inflammation response.NEW & NOTEWORTHY The mRNA expression of inflammatory cytokines in the HRW group was lower than in the CSAA group. HRW reversed hepatocyte apoptosis as well as hepatic inflammation and fibrosis in NASH specimens. Molecular hydrogen inhibits LPS-induced inflammation via an HO-1/interleukin 10 (IL-10)-independent pathway. HRW improved hepatic steatosis in the CSAA + HRW group. Sirt1 induction by molecular hydrogen via the HO-1/AMPK/PPARα/PPARγ pathway suppresses palmitate-mediated abnormal fat metabolism.
Assuntos
Heme Oxigenase-1/metabolismo , Hepatócitos/efeitos dos fármacos , Hidrogênio/farmacologia , Interleucina-10/metabolismo , Cirrose Hepática Experimental/prevenção & controle , Fígado/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Sirtuína 1/metabolismo , Água/farmacologia , Animais , Hepatócitos/enzimologia , Hepatócitos/patologia , Hidrogênio/química , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/metabolismo , Lipólise/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Cirrose Hepática Experimental/enzimologia , Cirrose Hepática Experimental/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/patologia , Células RAW 264.7 , Transdução de SinaisRESUMO
By utilizing scanning tunneling microscopy (STM), the self-assembled nanostructures of three characteristic aldehydes have been examined at the solution-solid interface. By introducing the active reactant 5-aminoisophthalic acid (5-AIPA), we succeeded in changing the self-assembled molecular structures through the condensation reaction and obtained the information on structural transformation in real time. The corresponding carboxyl conjugated derivatives were formed in situ and developed into the closely packed and ordered molecular architectures via hydrogen bonds at the solution-solid surface. The relevant simulations have been utilized to interpret the mechanisms of forming the nanostructures. The corresponding theoretical calculation is used to explain the reaction mechanism. Compared with the traditional ways, the on-surface condensation reaction in situ could not only provide a more convenient method for regulating the self-assembled architectures but also offer a promising strategy for building functional nanostructures and devices.
RESUMO
To investigate the epidemic profile and genetic diversity of porcine bocavirus (PBoV), 281 clinical samples, including 236 intestinal tissue samples and 45 fecal samples were collected from diarrheic piglets on 37 different pig farms in central China, and two SYBR Green I-based quantitative PCR assays were developed to detect PBoV1/2 and PBoV3/4/5, respectively. One hundred forty-eight (52.67%) of the 281 clinical samples were positive for PBoV1/2, 117 (41.63%) were positive for PBoV3/4/5, 55 (19.57%) were positive for both PBoV1/2 and PBoV3/4/5, and 86.49% (32/37) of the pig farms were positive for PBoV. Overall, the prevalence of PBoV was 74.73% (210/281) in central China. Subsequently, nearly full-length genomic sequences of two PBoV strains (designated CH/HNZM and PBoV-TY) from two different farms were determined. Phylogenetic analysis demonstrated that the two PBoV strains obtained in this study belonged to the PBoV G2 group and had a close relationship to 10 other PBoV G2 strains but differed genetically from PBoV G1, PBoV G3, and seven other bocaviruses. CH/HNZM and PBoV-TY were closely related to the PBoV strain GD18 (KJ755666), which may be derived from the PBoV strains 0912/2012 (MH558677) and 57AT-HU (KF206160) through recombination. Compared with reference strain ZJD (HM053694)-China, more amino acid variation was found in the NS1 proteins of CH/HNZM and PBoV-TY. These data extend our understanding of the molecular epidemiology and evolution of PBoV.
Assuntos
Bocavirus/genética , Infecções por Parvoviridae/virologia , Doenças dos Suínos/virologia , Animais , China , Fezes/virologia , Variação Genética/genética , Epidemiologia Molecular/métodos , Filogenia , Prevalência , SuínosRESUMO
Organ transplantation is the optimal treatment for terminal and irreversible organ failure. Achieving transplantation tolerance has long been the ultimate goal in the field of transplantation. Regulatory T cell (Treg)-based therapy is a promising novel approach for inducing donor organ-specific tolerance. Tregs play critical roles in the maintenance of immune homeostasis and self-tolerance, by promoting transplantation tolerance through a variety of mechanisms on different target cells, including anti-inflammatory cytokine production, induction of apoptosis, disruption of metabolic pathways, and mutual interaction with dendritic cells. The continued success of Treg-based therapy in the clinical setting is critically dependent on preclinical studies that support its translational potential. However, although some initial clinical trials of adoptive Treg therapy have successively demonstrated safety and efficacy for immunosuppressant minimization and transplantation tolerance induction, most Treg-based hematopoietic stem cell and solid organ clinical trials are still in their infancy. These clinical trials have not only focused on safety and efficacy but also included optimization and standardization protocols of good manufacturing practice regarding cell isolation, expansion, dosing, timing, specificity, quality control, concomitant immunosuppressants, and post-administration monitoring. We herein report a brief introduction of Tregs, including their phenotypic and functional characterization, and focus on the clinical translation of Treg-based therapeutic applications in the setting of transplantation.
Assuntos
Transplante de Órgãos , Tolerância ao Transplante , Tolerância Imunológica , Linfócitos T ReguladoresRESUMO
Mamestra brassicae L. is an important, regionally migratory pest of vegetable crops in Europe and Asia. Its migratory activity contributes significantly to population outbreaks, causing severe crop yield losses. Because an in-depth understanding of flight performance is key to revealing migratory patterns, here we used a computer-linked flight mill and stroboscope to study the flight ability and wingbeat frequency (WBF) of M. brassicae in relation to sex, age, temperature, and relative humidity (RH). The results showed that age significantly affected the flight ability and WBF of M. brassicae, and 3-d-old individuals performed the strongest performance (total flight distance: 45.6 ± 2.5 km; total flight duration: 9.3 ± 0.3 h; WBF: 44.0 ± 0.5 Hz at 24°C and 75% RH). The age for optimal flight was considered to be 2-3 d old. Temperature and RH also significantly affected flight ability and WBF; flight was optimal from 23°C to 25°C and 64-75% RH. Because M. brassicae thus has great potential to undertake long-distance migration, better knowledge of its flight behavior and migration will help establish a pest forecasting and early-warning system.
Assuntos
Voo Animal , Mariposas/fisiologia , Asas de Animais/fisiologia , Fatores Etários , Animais , Feminino , Umidade , Masculino , Fatores Sexuais , TemperaturaRESUMO
BACKGROUND: Cyclosporine-A (CsA) is an immunosuppressant indicated for various immunological diseases; however, it can induce chronic kidney injury. Oxidative stress and apoptosis play a crucial role in CsA-induced nephrotoxicity. The present study evaluated the protective effect of combining 5-aminolaevulinic acid with iron (5-ALA/SFC), a precursor of heme synthesis, to enhance HO-1 activity against CsA-induced chronic nephrotoxicity. METHODS: Mice were divided into three groups: the control group (using olive oil as a vehicle), CsA-only group, and CsA+5-ALA/SFC group. After 28 days, the mice were sacrificed, and blood and kidney samples were collected. In addition to histological and biochemical examination, the mRNA expression of proinflammatory and profibrotic cytokines was assessed. RESULTS: Renal function in the 5-ALA/SFC treatment group as assessed by the serum creatinine and serum urea nitrogen levels was superior to that of the CsA-only treatment group, demonstrating that 5-ALA/SFC significantly attenuated CsA-induced kidney tissue inflammation, fibrosis, apoptosis, and tubular atrophy, as well as reducing the mRNA level of TNF-α, IL-6, TGF-ß1, and iNOS while increasing HO-1. CONCLUSION: The activity of 5-ALA/SFC has important implications for clarifying the mechanism of HO-1 activity in CsA-induced nephrotoxicity and may provide a favorable basis for clinical therapy.
Assuntos
Ciclosporina/efeitos adversos , Fibrose/prevenção & controle , Heme Oxigenase-1/metabolismo , Ácidos Levulínicos/farmacologia , Nefrite Intersticial/patologia , Nefrite Intersticial/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Atrofia/prevenção & controle , Citocinas/genética , Quimioterapia Combinada , Heme Oxigenase-1/efeitos dos fármacos , Inflamação/prevenção & controle , Ferro/farmacologia , Ferro/uso terapêutico , Ácidos Levulínicos/uso terapêutico , Camundongos , Nefrite Intersticial/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/análise , Ácido AminolevulínicoRESUMO
BACKGROUND: This study aimed to investigate the protective effect of 5-aminolevulinic acid (5-ALA) and sodium ferrous citrate (SFC) against binge alcohol-induced gut leakiness and inflammatory liver disease in HIV transgenic (TG) rats. METHODS: TG rats were treated with 3 consecutive doses of binge ethanol (EtOH) with or without 5-ALA/SFC. Blood and liver tissue samples were collected at 6 hours following the last dose of EtOH. RESULTS: Compared with the wild-type (WT) rats, the TG rats showed increased sensitivity to alcohol-mediated inflammation, as evidenced by the significantly elevated levels of serum endotoxin, AST, ALT, ED1, and ED2 staining in liver. In contrast, 5-ALA/SFC improved the above biochemical and histochemical profiles. 5-ALA/SFC also attenuated the up-regulated mRNA expression of leptin and CCL2. Furthermore, down-regulated intestinal ZO-1 protein expression was also inhibited by 5-ALA/SFC. Moreover, the expressions of HO-1, HO-2, Sirt1, and related signal transduction molecules in liver were increased by 5-ALA/SFC. These results demonstrated that 5-ALA/SFC treatment ameliorated binge alcohol exposure liver injury in a rat model of HIV-infected patients by reducing macrophage activation and expression of inflammatory cytokines/chemokines, and by inducing HO-1, HO-2, and Sirt1 expression. CONCLUSIONS: Taken together, these findings suggested that treatment with 5-ALA/SFC has a potential therapeutic effect for binge alcohol exposure liver injury in HIV-infected patients.
Assuntos
Ácido Aminolevulínico/farmacologia , Consumo Excessivo de Bebidas Alcoólicas/fisiopatologia , Etanol/efeitos adversos , Hepatite/prevenção & controle , Intestinos/fisiopatologia , Permeabilidade/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Antígenos CD/biossíntese , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/biossíntese , Antígenos de Diferenciação Mielomonocítica/imunologia , Aspartato Aminotransferases/sangue , Moléculas de Adesão Celular Neuronais/genética , Ácido Cítrico , Endotoxinas/sangue , Infecções por Enterobacteriaceae/microbiologia , Compostos Ferrosos , Infecções por HIV/complicações , HIV-1/genética , Heme Oxigenase (Desciclizante)/biossíntese , Heme Oxigenase-1/biossíntese , Hepatite/sangue , Hepatite/complicações , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/sangue , Fígado/metabolismo , Ratos , Ratos Transgênicos , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/imunologia , Sirtuína 1/biossíntese , Células-Tronco , Triglicerídeos/metabolismo , Proteína da Zônula de Oclusão-1/biossíntese , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genéticaRESUMO
BACKGROUND: Liver transplantation (LT) is considered the standard treatment for end-stage liver disease, but ideal donors remain in limited supply, resulting in an unavoidable increase in the need to use grafts from marginal donors. The attenuation of ischemia-reperfusion injury (IRI) in such marginal donors is therefore crucial for reducing the possibility of the primary non-function of grafts and graft loss. Some reports have found that molecular-hydrogen showed antioxidant and anti-inflammatory effects in preventing IRI in some non-hepatic transplant models. Therefore, we investigated whether or not molecular-hydrogen could attenuate IRI in LT model rats. METHODS: We used a hydrogen-rich water bath to dissolve hydrogen into solution and graft tissues and performed isogenic and orthotopic LT in Lewis rats with University of Wisconsin (UW) solution. Blood and tissue samples were collected 6 h after the reperfusion. Hepatic enzymes in serum were measured. Pathological findings including the expressions of cytokines and heme oxygenase (HO)-1 in liver tissues were evaluated. RESULTS: The concentration of hydrogen inside the graft tissues increased depending on the storage time, plateauing after 1 h. Serum liver enzyme levels were significantly lower and the histology score of liver damage markedly attenuated in the group given grafts preserved in hydrogen-rich UW solution than in the control group. The hydrogen-rich UW solution group also showed less oxidative damage and hepatocyte apoptosis than the control group, and the expression of proinflammatory cytokines tended to be lower while the protein levels of HO-1 were significantly increased (n = 3-12 per group, P < 0.05). CONCLUSIONS: Storage of liver grafts in hydrogen-rich UW solution resulted in superior functional and morphologic protection against IRI via the up-regulation of HO-1 expression.
Assuntos
Hidrogênio , Rim/irrigação sanguínea , Transplante de Fígado , Soluções para Preservação de Órgãos , Preservação de Órgãos/métodos , Traumatismo por Reperfusão/prevenção & controle , Adenosina , Alopurinol , Animais , Apoptose , Temperatura Baixa , Glutationa , Hepatócitos/citologia , Concentração de Íons de Hidrogênio , Inflamação/prevenção & controle , Insulina , Masculino , Estresse Oxidativo , RNA Mensageiro/metabolismo , Rafinose , Ratos , Ratos Endogâmicos LewRESUMO
BACKGROUND: Mucopolysaccharidosis (MPS) VI is a rare, autosomal recessive congenital metabolic disorder caused by deficient activity of the lysosomal metabolic enzyme, N-acetylgalactosamine 4-sulfatase. Enzyme replacement therapy (ERT) is the current treatment for MPS VI, although it involves limited compliance to the therapy and high cost. The aim of this study was to develop a new method of treatment by conducting an orthotopic liver transplantation (LTx) using an animal model of human MPS VI, and to evaluate and examine its effectiveness for treating MPS VI. METHODS: LTx was carried out from normal unaffected to affected MPS VI rats (MPR), which were then killed after LTx, and tissues from the heart, spleen, and knee joint, as well as serum, collected for biological and morphologic evaluation. RESULTS: Liver-transplanted (LTx) MPR had the same level of N-acetylgalactosamine 4-sulfatase activity in the liver and lungs as normal unaffected MPR, and the urinary secretion of mucopolysaccharides/glycosaminoglycan (GAG) in LTx MPR was significantly decreased. Furthermore, on histopathology, the spleens of LTx MPR showed elimination of vacuole cells. In the knee joints, growth plates became thinner, and on radiography the facial and cranial bones of LTx MPR were morphologically normal. CONCLUSIONS: LTx from normal to affected MPR was effective for symptoms of MPS and accumulation of GAG, suggesting that LTx could be a promising alternative approach for MPS VI.
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Transplante de Fígado , Mucopolissacaridose VI/cirurgia , Animais , Ratos , Ratos Wistar , Resultado do TratamentoRESUMO
Ischemia-reperfusion (IR) injury is a kind of injury resulting from the restoration of the blood supply after blood vessel closure during liver transplantation and is the main cause of graft failure. The pathophysiological mechanisms of hepatic IR include a variety of oxidative stress responses. Hepatic IR is characterized by ischemia and hypoxia inducing oxidative stress, immune response and apoptosis. Fat-denatured livers are also used as donors due to the lack of liver donors. Fatty liver is less tolerant to IR than normal liver. Heme oxygenase (HO) is an enzyme that breaks down hemoglobin to bilirubin, ferrous iron and carbon monoxide (CO). Inducible HO subtype HO-1 is an important protective molecule in mammalian cells used to improve acute and chronic liver injury owing to its characteristic anti-inflammatory and anti-apoptotic qualities. HO-1 degrades heme, and its reaction product CO has been shown to reduce hepatic IR injury and increase the survival rate of grafts. As an induced form of HO, HO-1 also exerts a protective effect against liver IR injury and may be useful as a new strategy of ameliorating this kind of damage. This review summarizes the protective effects of HO-1 in liver IR injury, especially in fatty liver.
Assuntos
Fígado Gorduroso/enzimologia , Heme Oxigenase-1/metabolismo , Fígado/enzimologia , Traumatismo por Reperfusão/enzimologia , Animais , Bilirrubina/metabolismo , Dióxido de Carbono/metabolismo , Fígado Gorduroso/metabolismo , Hemoglobinas/metabolismo , Humanos , Ferro/metabolismo , Fígado/metabolismo , Fígado/patologia , Traumatismo por Reperfusão/metabolismoRESUMO
Scleroderma or systemic sclerosis (SSc) is a clinically heterogeneous rheumatological autoimmune disease affecting the skin, internal organs and blood vessels. There is at present no effective treatment for this condition. Our study investigated the effects of 5-aminolevulinic acid (5-ALA), which is a precursor of haem synthesis, on graft-vs-host disease (GvHD)-induced SSc murine model. Lymphocytes were intravenously injected from donor mice (B10.D2) into recipient BALB/c mice (recombination-activating gene 2 (Rag-2)-null mice) deficient in mature T and B cells to induce sclerodermatous GvHD (scl-GvHD). To investigate the effect of 5-ALA on scl-GvHD, combination of 5-ALA and sodium ferrous citrate (SFC) was orally administered to the recipient mice for 9 weeks. 5-ALA/SFC treatment significantly reduced progressive inflammation and fibrosis in the skin and ears. Furthermore, 5-ALA/SFC suppressed mRNA expression of transforming growth factor-ß, type I collagen and inflammatory cytokines. These results indicate that the 5-ALA/SFC combination treatment has a protective effect against tissue fibrosis and inflammation in a murine scl-GvHD-induced skin and ear inflammation and fibrosis. Furthermore, the efficacy of 5-ALA/SFC suggests important implications of HO-1 protective activity in autoimmune diseases, and therefore, 5-ALA/SFC may have promising clinical applications. These findings suggested that the 5-ALA/SFC treatment may be the potential strategies for SSc.
Assuntos
Ácido Aminolevulínico/uso terapêutico , Citocinas/genética , Compostos Ferrosos/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Escleroderma Sistêmico/tratamento farmacológico , Pele/patologia , Ácido Aminolevulínico/farmacologia , Animais , Colágeno Tipo I/genética , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Compostos Ferrosos/farmacologia , Fibrose , Expressão Gênica/efeitos dos fármacos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/patologia , Heme Oxigenase-1/metabolismo , Inflamação/metabolismo , Inflamação/prevenção & controle , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Fotossensibilizantes/farmacologia , RNA Mensageiro/metabolismo , Escleroderma Sistêmico/patologia , Fator de Crescimento Transformador beta/genéticaRESUMO
Renal ischemia-reperfusion (I/R) injury is unavoidable in kidney transplantation (KTx) and frequently influences both short- and long-term allograft survival. Carbon monoxide (CO) has attracted attention as a medical gas with anti-inflammatory and anti-apoptotic effects. We investigated a new strategy for organ preservation using ex vivo application of high-pressure CO in an experimental rat KTx model. We preserved kidney grafts using a high-pressure chamber filled with mixed gases composed of CO and O2. We found that cold I/R injury resulted in progressive deterioration of renal graft function in University of Wisconsin solution, whereas CO significantly improved renal function. We confirmed that CO decreased oxidative stress and mRNA expression of proinflammatory cytokines and inhibited tubular apoptosis in the early phases. Western blot analysis demonstrated that CO increased phosphatidylinositol-3 kinase and phosphorylation of Akt and p38 mitogen-activated protein kinase. Furthermore, CO significantly alleviated tubular injury scores and suppressed the development of interstitial fibrosis at 100 days after KTx. Thus, high-pressure mixed CO and O2 gases successfully preserved rat kidney grafts for 24 h by protecting tubular epithelial cells from apoptosis and inhibiting inflammation.
Assuntos
Apoptose/efeitos dos fármacos , Monóxido de Carbono/farmacologia , Inflamação/prevenção & controle , Transplante de Rim/métodos , Rim/efeitos dos fármacos , Preservação de Órgãos/métodos , Adenosina/farmacologia , Alopurinol/farmacologia , Animais , Western Blotting , Temperatura Baixa , Citocinas/genética , Citocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Glutationa/farmacologia , Sobrevivência de Enxerto/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Insulina/farmacologia , Rim/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Masculino , Soluções para Preservação de Órgãos/farmacologia , Oxigênio/farmacologia , Pressão Parcial , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rafinose/farmacologia , Ratos Endogâmicos Lew , Traumatismo por Reperfusão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
BACKGROUND: Hypoxia causes cardiac disease via oxidative stress and mitochondrial dysfunction. 5-Aminolevulinic acid in combination with sodium ferrous citrate (ALA/SFC) has been shown to up-regulate heme oxygenase-1 (HO-1) and decrease macrophage infiltration and renal cell apoptosis in renal ischemia injury mice. However, its underlying mechanism remains largely unknown. The aim of this study was to investigate whether ALA/SFC could protect cardiomyocytes from hypoxia-induced apoptosis by autophagy via HO-1 signaling. MATERIALS & METHODS: Murine atrial cardiomyocyte HL-1 cells were pretreated with ALA/SFC and then exposed to hypoxia. RESULTS: ALA/SFC pretreatment significantly attenuated hypoxia-induced cardiomyocyte apoptosis, reactive oxygen species production, and mitochondrial injury, while it increased cell viability and autophagy levels. HO-1 expression by ALA/SFC was associated with up-regulation and nuclear translocation of Nrf-2, whereas Nrf-2 siRNA dramatically reduced HO-1 expression. ERK1/2, p38, and SAPK/JNK pathways were activated by ALA/SFC and their specific inhibitors significantly reduced ALA/SFC-mediated HO-1 upregulation. Silencing of either Nrf-2 or HO-1and LY294002, inhibitor of autophagy, abolished the protective ability of ALA/AFC against hypoxia-induced injury and reduced ALA/SFC-induced autophagy. CONCLUSION: Taken together, our data suggest that ALA/SFC induces autophagy via activation of MAPK/Nrf-2/HO-1 signaling pathway to protect cardiomyocytes from hypoxia-induced apoptosis.
Assuntos
Ácido Aminolevulínico/farmacologia , Autofagia/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Compostos Ferrosos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Cromonas/farmacologia , Ácido Cítrico , Inibidores Enzimáticos/farmacologia , Heme Oxigenase-1/metabolismo , Isquemia/prevenção & controle , Rim/irrigação sanguínea , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno , Morfolinas/farmacologia , Miócitos Cardíacos/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para CimaRESUMO
BACKGROUND: The fatty liver could increase the risk of serious acute ischemia reperfusion (I/R) injury, and hepatic steatosis is indeed a major risk factor for hepatic failure after grafting a fatty liver. MATERIALS & METHODS: Fatty liver models of methionine- and choline-deficient high-fat mice were subjected to I/R injury with or without 5-aminolevulinic acid (5-ALA)/sodium ferrous citrate (SFC) treatment. Levels of hepatic enzymes, lipid peroxidation and apoptosis, inflammatory cytokines and heme oxygenase (HO)-1, and the carbon monoxide (CO) in the liver, and reactive oxygen species (ROS), inflammatory cytokines and members of the signaling pathway in isolated Kupffer were assessed. RESULTS: Alanine aminotransferase and aspartate aminotransferase levels, the number of necrotic areas, thiobarbituric acid reactive substance content, TUNEL-positive cells, infiltrated macrophages, and the inflammatory cytokine expression after I/R injury were dramatically decreased, whereas the endogenous CO concentrations and the HO-1 expression were significantly increased by 5-ALA/SFC treatment. The expression of toll-like receptors 2 and 4, NF-κB and inflammatory cytokines and ROS production in Kupffer cells were significantly decreased with 5-ALA/SFC treatment. CONCLUSION: 5-ALA/SFC significantly attenuates the injury level in the fatty liver after I/R injury.
Assuntos
Ácido Aminolevulínico/administração & dosagem , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/imunologia , Compostos Ferrosos/administração & dosagem , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/imunologia , Animais , Citocinas/imunologia , Combinação de Medicamentos , Fígado Gorduroso/patologia , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/imunologia , Camundongos , Espécies Reativas de Oxigênio/imunologia , Traumatismo por Reperfusão/patologia , Resultado do TratamentoRESUMO
Hypoxic-ischemic encephalopathy (HIE) is one of the leading causes of morbidity and mortality in neonates. Because of high concentrations of sensitive immature cells, metal-catalyzed free radicals, non-saturated fatty acids, and low concentrations of antioxidant enzymes, the brain requires high levels of oxygen supply and is, thus, extremely sensitive to hypoxia. Strong evidence indicates that oxidative stress plays an important role in pathogenesis and progression. Following hypoxia and ischemia, reactive oxygen species (ROS) production rapidly increases and overwhelms antioxidant defenses. A large excess of ROS will directly modify or degenerate cellular macromolecules, such as membranes, proteins, lipids, and DNA, and lead to a cascading inflammatory response, and protease secretion. These derivatives are involved in a complex interplay of multiple pathways (e.g., inflammation, apoptosis, autophagy, and necrosis) which finally lead to brain injury. In this review, we highlight the molecular mechanism for oxidative stress in HIE, summarize current research on therapeutic strategies utilized in combating oxidative stress, and try to explore novel potential clinical approaches.