Blueberry attenuates liver injury in metabolic dysfunction-associated liver disease by promoting the expression of mitofilin/Mic60 in human hepatocytes and inhibiting the production of superoxide / 细胞与分子免疫学杂志

Objective To study the effect and mechanism of blueberry on regulating the mitochondrial inner membrane protein mitofilin/Mic60 in an in vitro model of metabolic dysfunction-associated liver disease (MAFLD). Methods L02 human hepatocytes were induced by free fatty acids (FFA) to establish MAFLD cell model. A normal group, a model group, an 80 μg/mL blueberry treatment group, a Mic60 short hairpin RNA (Mic60 shRNA) transfection group, and Mic60 knockdown combined with an 80 μg/mL blueberry treatment group were established. The intracellular lipid deposition was observed by oil red O staining, and the effect of different concentrations of blueberry pulp on the survival rate of L02 cells treated with FFA was measured by MTT assay. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TC), superoxide dismutase (SOD) activity, glutathione (GSH) and malondialdehyde (MDA) contents were measured by visible spectrophotometry. The expression of reactive oxygen species (ROS) in hepatocytes was observed by fluorescence microscopy, and the mRNA and protein expression of Mic60 were detected by real-time quantitative PCR and Western blot analysis, respectively. Results After 24 hours of FFA stimulation, a large number of red lipid droplets in the cytoplasm of L02 cells was observed, and the survival rate of L02 cells treated with 80 μg/mL blueberry was higher. The results of ALT, AST, TG, TC, MDA and the fluorescence intensity of ROS in blueberry treated group were lower than those in model group, while the levels of SOD, GSH, Mic60 mRNA and protein in blueberry treated group were higher than those in model group. Conclusion Blueberry promotes the expression of Mic60, increases the levels of SOD and GSH in hepatocytes, and reduces the production of ROS, thus alleviating the injury of MAFLD hepatocytes and regulating the disorder of lipid metabolism.

Treadmill exercise alleviates neuropathic pain by regulating mitophagy of the anterior cingulate cortex in rats / 生理学报

This study aimed to investigate the effect of treadmill exercise on neuropathic pain and to determine whether mitophagy of the anterior cingulate cortex (ACC) contributes to exercise-mediated amelioration of neuropathic pain. Chronic constriction injury of the sciatic nerve (CCI) was used to establish a neuropathic pain model in Sprague-Dawley (SD) rats. Von-Frey filaments were used to assess the mechanical paw withdrawal threshold (PWT), and a thermal radiation meter was used to assess the thermal paw withdrawal latency (PWL) in rats. qPCR was used to evaluate the mRNA levels of Pink1, Parkin, Fundc1, and Bnip3. Western blot was used to evaluate the protein levels of PINK1 and PARKIN. To determine the impact of the mitophagy inducer carbonyl cyanide m-chlorophenylhydrazone (CCCP) on pain behaviors in CCI rats, 24 SD rats were randomly divided into CCI drug control group (CCI+Veh group), CCI+CCCP low-dose group (CCI+CCCP0.25), CCI+CCCP medium-dose group (CCI+CCCP2.5), and CCI+CCCP high-dose group (CCI+CCCP5). Pain behaviors were assessed on 0, 1, 3, 5, and 7 days after modeling. To explore whether exercise regulates pain through mitophagy, 24 SD rats were divided into sham, CCI, and CCI+Exercise (CCI+Exe) groups. The rats in the CCI+Exe group underwent 4-week low-moderate treadmill training one week after modeling. The mechanical pain and thermal pain behaviors of the rats in each group were assessed on 0, 7, 14, 21, and 35 days after modeling. Western blot was used to detect the levels of the mitophagy-related proteins PINK1, PARKIN, LC3 II/LC3 I, and P62 in ACC tissues. Transmission electron microscopy was used to observe the ultrastructure of mitochondrial morphology in the ACC. The results showed that: (1) Compared with the sham group, the pain thresholds of the ipsilateral side of the CCI group decreased significantly (P < 0.001). Meanwhile, the mRNA and protein levels of Pink1 were significantly higher, and those of Parkin were lower in the CCI group (P < 0.05). (2) Compared with the CCI+Veh group, each CCCP-dose group showed higher mechanical and thermal pain thresholds, and the levels of PINK1 and LC3 II/LC3 I were elevated significantly (P < 0.05, P < 0.01). (3) The pain thresholds of the CCI+Exe group increased significantly compared with those of the CCI group after treadmill intervention (P < 0.001, P < 0.01). Compared with the CCI group, the protein levels of PINK1 and P62 were decreased (P < 0.001, P < 0.01), and the protein levels of PARKIN and LC3 II/LC3 I were increased in the CCI+Exe group (P < 0.01, P < 0.05). Rod-shaped mitochondria were observed in the ACC of CCI+Exe group, and there were little mitochondrial fragmentation, swelling, or vacuoles. The results suggest that the mitochondrial PINK1/PARKIN autophagy pathway is blocked in the ACC of neuropathic pain model rats. Treadmill exercise could restore mitochondrial homeostasis and relieve neuropathic pain via the PINK1/PARKIN pathway.

Unfolded protein response signaling in mitochondria / 生理学报

The mitochondrial unfolded protein response is an important component of the mitochondrial protein quality control program. It can effectively remove unfolded or misfolded proteins under stress, and maintain a stable and healthy mitochondrial pool. The mitochondrial unfolded protein response is coordinated by multiple signaling pathways. The classical ATF4/ATF5-CHOP pathway is induced by accumulation of unfolded or misfolded proteins in the mitochondrial matrix, which reduces stress toxicity by regulating molecular chaperones and proteases. Sirt3-FOXO3a-SOD2 pathway, located in the mitochondrial matrix, plays an important role in anti-oxidative damage. The ERα-NRF1-HTRA2 pathway mainly removes unfolded proteins in the mitochondrial membrane space and improves the quality control of mitochondrial proteins. These three signaling pathways work both independently and cooperatively to enhance mitochondrial capacity and maintain health under stress.

Efficacy of phosphocreatine pre-administration on XIAP and Smac in ischemic penumbra of rats with focal cerebral ischemia reperfusion injury

Abstract Purpose: To observe the efficacy of phosphocreatine pre-administration (PCr-PA) on X-linked inhibitor of apoptosis protein (XIAP), the second mitochondia-derived activator of caspase (Smac) and apoptosis in the ischemic penumbra of rats with focal cerebral ischemia-reperfusion injury (CIRI). Methods: A total of 60 healthy male Sprague Dawley (SD) rats were randomly divided into three groups (n=20): group A (the sham operation group), group B <intraperitoneally injected with 20 mg/kg (10 mg/ml) of saline before preparing the ischemia-reperfusion (IR) model>, and group C <intraperitoneally injected with 20 mg/kg (10 mg/ml) of PCr immediately before preparing the IR model>. After 24 h for reperfusion, the neurological function was evaluated and the tissue was sampled to detect expression of XIAP, Smac and caspase-3 positive cells in the ischemic penumbra so as to observe the apoptosis. Results: Compared with group B, neurological deficit scores, numbers of apoptotic cells, expression of Smac,caspase-9 and the numbers of Caspase-3 positive cells were decreased while expression of XIAP were increased in the ischemic penumbra of group C. Conclusions: Phosphocreatine pre-administration may elicit neuroprotective effects in the brain by increasing expression of X-linked inhibitor of apoptosis protein, reducing expression of second mitochondia-derived activator of caspase, and inhibiting the apoptosis in the ischemic penumbra.

Down-regulation of single-stranded DNA-binding protein 1 expression induced by HCMV infection promotes lipid accumulation in cells

The objective of this study was to observe the infection of human cytomegalovirus (HCMV) to human umbilical vein endothelial cells, and its effect on the expression of single-stranded DNA-binding protein (SSBP1) and on lipid metabolism in endothelial cells. We screened the differential expression of mRNAs after HCMV infection by suppression subtractive hybridization and the expression levels of SSBP1 mRNA and protein after HCMV infection by real-time PCR and western blot. After verification of successful infection by indirect immunofluorescent staining and RT-PCR, we found a differential expression of lipid metabolism-related genes including LDLR, SCARB, CETP, HMGCR, ApoB and LPL induced by HCMV infection. The expression levels of SSBP1 mRNA and protein after HCMV infection were significantly down-regulated. Furthermore, we found that upregulation of SSBP1 inhibited the expression of atherosclerosis-associated LDLR, SCARB, HMGCR, CETP as well as the accumulation of lipids in the cells. The results showed that the inhibition of SSBP1 by HCMV infection promotes lipid accumulation in the cells.

The consensus sequence of FAMLF alternative splice variants is overexpressed in undifferentiated hematopoietic cells

The familial acute myeloid leukemia related factor gene (FAMLF) was previously identified from a familial AML subtractive cDNA library and shown to undergo alternative splicing. This study used real-time quantitative PCR to investigate the expression of the FAMLF alternative-splicing transcript consensus sequence (FAMLF-CS) in peripheral blood mononuclear cells (PBMCs) from 119 patients with de novo acute leukemia (AL) and 104 healthy controls, as well as in CD34+ cells from 12 AL patients and 10 healthy donors. A 429-bp fragment from a novel splicing variant of FAMLF was obtained, and a 363-bp consensus sequence was targeted to quantify total FAMLF expression. Kruskal-Wallis, Nemenyi, Spearman's correlation, and Mann-Whitney U-tests were used to analyze the data. FAMLF-CS expression in PBMCs from AL patients and CD34+ cells from AL patients and controls was significantly higher than in control PBMCs (P<0.0001). Moreover, FAMLF-CS expression in PBMCs from the AML group was positively correlated with red blood cell count (rs =0.317, P=0.006), hemoglobin levels (rs =0.210, P=0.049), and percentage of peripheral blood blasts (rs =0.256, P=0.027), but inversely correlated with hemoglobin levels in the control group (rs =–0.391, P<0.0001). AML patients with high CD34+ expression showed significantly higher FAMLF-CS expression than those with low CD34+ expression (P=0.041). Our results showed that FAMLF is highly expressed in both normal and malignant immature hematopoietic cells, but that expression is lower in normal mature PBMCs.

Uncoupling protein-2 mRNA expression in mice subjected to intermittent hypoxia / Expressão do mRNA da uncoupling protein-2 em camundongos submetidos à hipóxia intermitente

Objective: To investigate the effect of intermittent hypoxia-a model of obstructive sleep apnea (OSA)-on pancreatic expression of uncoupling protein-2 (UCP2), as well as on glycemic and lipid profiles, in C57BL mice. Methods: For 8 h/day over a 35-day period, male C57BL mice were exposed to intermittent hypoxia (hypoxia group) or to a sham procedure (normoxia group). The intermittent hypoxia condition involved exposing mice to an atmosphere of 92% N and 8% CO2 for 30 s, progressively reducing the fraction of inspired oxygen to 8 ± 1%, after which they were exposed to room air for 30 s and the cycle was repeated (480 cycles over the 8-h experimental period). Pancreases were dissected to isolate the islets. Real-time PCR was performed with TaqMan assays. Results: Expression of UCP2 mRNA in pancreatic islets was 20% higher in the normoxia group than in the hypoxia group (p = 0.11). Fasting serum insulin was higher in the hypoxia group than in the normoxia group (p = 0.01). The homeostasis model assessment of insulin resistance indicated that, in comparison with the control mice, the mice exposed to intermittent hypoxia showed 15% lower insulin resistance (p = 0.09) and 21% higher pancreatic β-cell function (p = 0.01). Immunohistochemical staining of the islets showed no significant differences between the two groups in terms of the area or intensity of α- and β-cell staining for insulin and glucagon. Conclusions: To our knowledge, this is the first report of the effect of intermittent hypoxia on UCP2 expression. Our findings suggest that UCP2 regulates insulin production in OSA. Further study of the role that UCP2 plays in the glycemic control of OSA patients is warranted. .

Objetivo: Investigar o efeito da hipóxia intermitente com um modelo de apneia obstrutiva do sono (AOS) sobre a expressão de uncoupling protein-2 (UCP2), assim como sobre perfis glicêmicos e lipídicos, em camundongos C57BL. Métodos: Camundongos C57BL machos foram expostos a hipóxia intermitente ou hipóxia simulada (grupo controle) 8 h/dia durante 35 dias. A condição de hipóxia intermitente envolveu a exposição dos camundongos a uma atmosfera de 92% de N e 8% de CO2 por 30 s, com redução progressiva de fração de O2 inspirado até 8 ± 1%, seguida por exposição a ar ambiente por 30 s e repetições do ciclo (480 ciclos no período experimental de 8 h). Os pâncreas foram dissecados para isolar as ilhotas. Foi realizada PCR em tempo real utilizando o método TaqMan. Resultados: A expressão do mRNA da UCP2 nas ilhotas pancreáticas foi 20% maior no grupo controle que no grupo hipóxia (p = 0,11). A insulina sérica de jejum foi maior no grupo hipóxia do que no grupo controle (p = 0,01). O modelo de avaliação da homeostase de resistência à insulina indicou que, em comparação com os camundongos controle, aqueles expostos à hipóxia intermitente apresentaram 15% menor resistência à insulina (p = 0,09) e 21% maior função das células beta (p = 0,01). A coloração das ilhotas pancreáticas por imuno-histoquímica não mostrou diferenças significativas entre os grupos em termos da área ou da intensidade das células alfa e beta, marcadas por insulina e glucagon. Conclusões: Segundo nosso conhecimento, esta é a primeira descrição do efeito da hipóxia intermitente sobre a expressão da UCP2. Nossos achados sugerem que UCP2 regula a produção de insulina na AOS. Futuras investigações sobre o papel da UCP2 no controle glicêmico em pacientes com AOS são justificadas. .

Brown adipose tissue: what have we learned since its recent identification in human adults / Tecido adiposo marrom: o que aprendemos desde sua recente identificação em humanos adultos

Brown adipose tissue, an essential organ for thermoregulation in small and hibernating mammals due to its mitochondrial uncoupling capacity, was until recently considered to be present in humans only in newborns. The identification of brown adipose tissue in adult humans since the development and use of positron emission tomography marked with 18-fluorodeoxyglucose (PET-FDG) has raised a series of doubts and questions about its real importance in our metabolism. In this review, we will discuss what we have learnt since its identification in humans as well as both new and old concepts, some of which have been marginalized for decades, such as diet-induced thermogenesis. Arq Bras Endocrinol Metab. 2014;58(9):889-99.

O tecido adiposo marrom, órgão essencial para a termorregulação de animais hibernantes e pequenos devido à sua capacidade desacopladora, era até poucos anos considerado presente apenas em recém-nascidos na espécie humana. A identificação do tecido adiposo marrom em adultos com o desenvolvimento e uso da tomografia de emissão de pósitron marcado com 18-fluorodesoxiglicose (PET-FDG) gerou questões sobre sua real importância para nosso metabolismo. Nesta revisão, discutiremos o que aprendemos nesse tempo, assim como conceitos antigos e novos, alguns marginalizados por décadas, como a termogênese induzida por dieta. Arq Bras Endocrinol Metab. 2014;58(9):889-99.

Aggressive Multilocular Osteoblastoma in the Mandible: A Rare and Difficult Case to Diagnose

Osteoblastoma is a benign neoplasia and is uncommon in the jaws. In some cases, this lesion presents extremely aggressive local characteristics and is termed aggressive osteoblastoma. Because the clinical, radiographic and histopathologic characteristics are similar to those of a variety of benign and malignant tumors, it poses a diagnostic dilemma. This report presents a case of an aggressive osteoblastoma in the mandible and discusses the differential diagnosis of this lesion. A 13-year-old white male sought the Stomatology Clinic at the State University of Paraíba, Campina Grande, PB, Brazil, complaining of asymptomatic swelling on the left side of his face. Cone-beam computerized tomography showed a multilocular, hypodense bone lesion, located in the body of the left mandible and lower third of the ascending ramus. The initial diagnostic hypothesis was juvenile ossifying fibroma or osteosarcoma. After histopathologic examination, the final diagnosis was aggressive osteoblastoma. Surgical resection with a safety margin was performed. There was no evidence of recurrence after a follow-up period of 4 years.

O osteoblastoma é uma neoplasia benigna e incomum nos maxilares. Em alguns casos esta lesão apresenta características locais extremamente agressivas, sendo denominada osteoblastoma agressivo. Devido às características clínicas, radiográficas e histopatológicas serem similares a uma variedade de tumores benignos e malignos, o seu diagnóstico é um dilema. Este relato apresenta o caso de um osteoblastoma agressivo na mandíbula e discute o diagnóstico diferencial desta lesão. Paciente, branco, 13 anos de idade, foi atendido na Clínica de Estomatologia da Universidade Estadual da Paraíba, Campina Grande, PB, Brasil, queixando-se de aumento de volume assintomático do lado esquerdo de sua face. A tomografia computadorizada de feixe cônico revelou uma lesão óssea hipodensa multilocular, localizada no corpo do lado esquerdo da mandíbula e no terço inferior do ramo ascendente da mandíbula. A hipótese diagnóstica foi de fibroma ossificante juvenil e osteosarcoma. Após exame histopatológico, o diagnóstico final foi osteoblastoma agressivo. Foi realizada ressecção cirúrgica com margem de segurança. Não houve sinais de recorrência após 4 anos de acompanhamento.

Elevated ferric, calcium and magnesium ions in the brain induce protein aggregation in brain mitochondria / El aumento de iones férricos, calcio y magnesio en el cerebro induce la agregación de proteínas en las mitocondrias del cerebro

OBJECTIVE: Alzheimer s disease and Parkinson s disease are two of several neurodegenerative disorders that affect the elderly. Although their aetiology remains uncertain, studies suggest that elevated aluminium or other metal ions in the brain directly influence the development of the histological abnormalities normally associated with these diseases; other investigations suggest that metal-ion-induced-dysfunction of mitochondria might be a critical factor. METHODS: In this study, the impact of elevated aluminum (Al3+), ferric (Fe3+), calcium (Ca2+) and magnesium (Mg2+) ions on brain histology and on the protein composition of brain mitochondria were evaluated. Rabbits were injected intra-cerebrally with 1.4% solutions of either aluminium chloride (AlCl3), ferric chloride (FeCl2), calcium chloride (CaCl2) or magnesium chloride (MgCl2) and sacrificed 10 days later. RESULTS: Histological analysis revealed that Al3+ but not the other ions induced neurofibrillary degeneration within the midbrain and medulla. Alternatively, SDS-PAGE revealed that Fe3+, Ca2+ and Mg2+ but not Al3+ induced alterations to the distribution of brain mitochondrial proteins. Both Fe3+ and Ca2+ triggered decreased concentration of three low molecular weight proteins (~7-14 kd) but Ca precipitated their total absence. Both ions led to increased concentration of a high molecular weight protein (~ 110 kd). In contrast, Mg2+ led to the total absence of the protein of lowest molecular weight (~7 kd) and increased concentration of a ~36 kd protein. CONCLUSION: These results suggest that elevation of some metal ions in the brain induces protein aggregation with the nature of the aggregation being highly ion dependent. The results also point toward major differences between the histopathological effect of Al3+ and other ions.

OBJETIVO: La enfermedad de Alzheimer y la enfermedad de Parkinson son dos de los varios trastornos neurodegenerativos que afectan al anciano. Aunque su etiologia sigue siendo incierta, los estudios sugieren que el aumento de los iones de aluminio, influyen directamente sobre el desarrollo de las anormalidades histológicas asociadas normalmente con estas enfermedades. Otras investigaciones sugieren que la disfunción de las mitocondrias, inducida por iones metálicos, pudiera ser un factor critico. MÉTODOS: Este estudio evalúa el impacto del aumento de los iones de aluminio (Al3+), los iones férricos (Fe3+), y los iones de calcio (Ca2+) y magnesio (Mg2+) sobre la histologia del cerebro y la composición proteica de las mitocondrias del cerebro. Un número de conejos recibieron inyecciones intracerebrales de soluciones al 1.4% de soluciones de cloruro de aluminio (AlCl3), cloruro ferroso (FeCl3), cloruro de calcio (CaCl2), o cloruro de magnesio (MgCl2), y fueron sacrificados después de 10 días. RESULTADOS: El análisis histológico reveló que el Al3+ indujo una degeneración neurofibrilar dentro del mesencéfalo y la médula, Sin embargo, esto no ocurrió con los otros iones. Alternativamente, la técnica de electroforesis SDS-PAGE reveló que los iones Fe3+, Ca2+ y Mg2+, a diferencia del ión Al3+, inducían alteraciones de la distribución de las proteínas mitocondriales cerebrales. Tanto el Fe3+ como el Ca2+ desencadenaron una disminución de la concentración de tres proteínas de bajo peso molecular (~7-14 kd) pero Ca2+ precipitó su ausencia total. Ambos iones condujeron a un aumento de una proteína de peso molecular alto (~ 110 kd). En cambio, Mg2+ llevó a la ausencia total de la proteína de más bajo peso molecular (~7 kd) y al aumento de la concentración de una proteína de ~36 kd. CONCLUSIÓN: Estos resultados parecen sugerir que la elevación de algunos iones de metal en el cerebro induce la agregación de la proteína, siendo la naturaleza de la agregación altamente dependiente de los iones. Los resultados también apuntan a grandes diferencias entre el efecto histopatológico del Al3+ y otros iones.

Infección por el virus de la Lengua azul: activación de señales celulares que inducen apoptosis / Bluetongue virus infection: signaling pathway activated during apoptosis

El virus de la Lengua azul (VLA) es un ARN virus de doble cadena que induce apoptosis tanto en cultivos celulares como en tejidos blanco. Con el fin de dilucidar el mecanismo de apoptosis en la infección por el VLA, en el presente trabajo examinamos en detalle, por la técnica de Western blot, las señales celulares de caspasas, Bax, citocromo c, Smac/DIABLO y factor nuclear kappa B (NF-kB) que se activan en la infección viral. Hemos comprobado que luego de la infección in vitro con el VLA, se detectó la activación de la caspasa 8 y con ello el mecanismo extrínseco de la apoptosis. También detectamos por primera vez no sólo la activación de miembros de la familia Bcl-2 (Bax), sino también la liberación del citocromo c y la proteína Smac/DIABLO, confirmando que en la infección por el VLA está involucrado el mecanismo secuencial intrínseco de la apoptosis. Asimismo, demostramos que la infección por el VLA activa el NF-kB y que la apoptosis es sustancialmente reducida mediante la inhibición del mismo. La activación de las señales celulares tales como Bax, citocromo c, Smac/DIABLO y NF-kB presentados en este trabajo, esclarecen los mecanismos apoptóticos durante la infección por el VLA para una mayor comprensión del papel primario que juega la apoptosis en la patogénesis del virus.

Bluetongue (BTV) is a double-stranded RNA virus that induces apoptosis both in mammalian cell cultures and in target tissues. To elucidate the apoptosis pathways in BTV infection, we have examined in detail the apoptosis mechanism by examination of caspases, Bax, cytochrome c, Smac/DIABLO and NF-kB signalling pathways. In this report, after cell infection with BTV, the activation of caspase 8 was detected, proving the extrinsic receptor binding apoptotic pathway. Apoptosis followed a sequential pathway involving the detection of activated Bcl-2 family members. Furthermore, its translocation to the mitochondria, as well as the release of cytochrome c and Smac/Diablo confirmed that BTV apoptosis involves the sequential intrinsic pathway. In addition, we demonstrated that NF-kB was activated following BTV infection and cell treatment with an inhibitor peptide before BTV infection, prevented NF-kB activation and substantially reduced cellular apoptosis. Our accumulating data concerning the activation of Bax, cytochrome c, Smac/DIABLO and NF-kB clarify the mechanism of apoptosis during BTV infection, and confer a better understanding of the primary role of apoptosis in BTV pathogenesis.

Activation of PPARgamma induces profound multilocularization of adipocytes in adult mouse white adipose tissues

We sought to determine the effects of activation of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) on multilocularization of adipocytes in adult white adipose tissue (WAT). Male C57BL/6 normal, db/db, and ob/ob mice were treated with agonists of PPAR-gamma, PPAR-alpha, or beta3-adrenoceptor for 3 weeks. To distinguish multilocular adipocytes from unilocular adipocytes, whole-mounted adipose tissues were co-immunostained for perilipin and collagen IV. PPAR-gamma activation with rosiglitazone or pioglitazone induced a profound change of unilocular adipocytes into smaller, multilocular adipocytes in adult WAT in a time-dependent, dose-dependent, and reversible manner. PPAR-alpha activation with fenofibrate did not affect the number of locules or remodeling. db/db and ob/ob obese mice exhibited less multilocularization in response to PPAR-gamma activation compared to normal mice. Nevertheless, all adipocytes activated by PPAR-gamma contained a single nucleus regardless of locule number. Multilocular adipocytes induced by PPAR-gamma activation contained substantially increased mitochondrial content and enhanced expression of uncoupling protein-1, PPAR-gamma coactivator-1-alpha , and perilipin. Taken together, PPAR-gamma activation induces profound multilocularization and enhanced mitochondrial biogenesis in the adipocytes of adult WAT. These changes may affect the overall function of WAT.

Propriedades Redox de canais de potássio mitocondriais ATP-sensíveis em cérebro e seu efeito neuroprotetor em excitotoxicidade / Redox properties of brain mitochondrial ATP-sensitive potassium channels and neuroprotective effects in excitotoxicity

Muitos estudos demonstram que a abertura de canais de ´KPOT.+` mitocondriais sensíveis à ATP (mito´K ind.ATP`) previnem contra danos promovidos por isquemia/reperfusao em coração. Em geral, esta proteçao envolve mudanças no estado redox mitocondrial. Em cérebro, sabe-se que agonistas farmacológicos de mito´K ind.ATP` também protegem em modelo de isquemia/reperfusão. Entretanto, os mecanismos envolvidos na prevenção de danos em cérebro ainda não estão claros. 0 objetivo principal deste trabalho é compreender os efeitos de canais de K+ mitocondriais ATP-sensíveis em tecido cerebral e os mecanismos pelos quais a sua ativação pode proteger contra danos promovidos por excitotoxicidade, uma das principais consequências de um evento isquêmico em cerebro. Neste contexto, demonstramos a proteção pelo mito´K ind.ATP` em modelo de excitotoxicidade induzida pela ativação direta de receptores NMDA, utilizando cultura de células granulosas de cerebelo. Paralelamente a essa proteção, verificamos que a ativação de mito´K ind.ATP` reduz a geração de espécies reativas de oxigênio (ROS)...

Effects of endotoxin on liver Smac apoptosis channel / 华中科技大学学报（医学）（英德文版）

To study the effect of endotoxin on liver apoptosis, L02 liver cells were cultured and passaged in vitro, and then stimulated by endotoxin at 10 mg/mL for 4, 8, 16 and 24 h respectively. Liver apoptosis was flow cytometrically and fluorescently detected. Immunohistochemistry was used to detect the delivery of smac and caspase9. The delivery of liver cell smac and the activity of caspase3 were measured by caspase3 assay kit. The hepatic failure models of rats were established by using D-galactosamine. The blood serum and liver tissues were collected for the detection of the liver function, the level of endotoxin and the activity of caspase3 by using chromogenic substrate limulus amebocyte lysate method (LAL) and caspase3 active assay kit. The expression of smac and caspase9 in liver cells was detected by Western blotting. With in vitro study, the L02 cells stimulated by LPS condensed into conglobation and formed apoptotic bodies. After those cells were stained by hoechst, the apoptotic cells displayed blue color under the fluorescent microscope. The apoptosis rate was increased over time and the apoptosis was mainly of advanced stage. Meanwhile, the rate of smac delivery and activity of caspase9 and caspase3 were increased on L02 cell membrane. In vivo, hepatic failure and obvious endotoxemia were induced by injection of more than 200 mg/kg D-GalN. Hepatic mitochondria smac was reduced with dosage of D-GalN and, on the contrary, the activity of caspase3 was increased. D-GalN at 200 mg/kg increased Caspase9 while D-GalN at 300 mg/kg decreased caspase9. Mitochondria signal channel plays an important role in the endotoxin-induced apoptosis of hepatic cells by promoting the release of smac from mitochondria to cytoplasm and activating caspase9 and caspase3 in its low-level channel.

Up-regulation of Bax and endonuclease G, and down-modulation of Bcl-X(L) involved in cardiotoxin III-induced apoptosis in K562 cells

Cardiotoxin III (CTX III), a basic polypeptide with 60 amino acid residues isolated from Naja naja atra venom, has been reported to have anticancer activity. CTX III-induced K562 cell apoptosis was confirmed by DNA fragmentation (DNA ladder, sub-G1 formation) and phosphatidylserine (PS) externalization with an IC50 value of 1.7 mug/ml at 48 h. A mechanistic analysis demonstrated that CTX III-induced apoptotic cell death was accompanied by up-regulation of both Bax and endonuclease G (Endo G), and downregulation of Bcl-X(L). CTX III had no effect on the levels of Bcl-2, Bid, XIAP survivin, and AIF proteins. CTX III treatment caused loss of the mitochondrial membrane potential (delta psi m), release of mitochondrial cytochrome c to the cytosol, and activation of both caspase-9 and -3. CTX III-induced apoptosis was significantly blocked by the broad-spectrum caspase inhibitor Z-VAD-FMK. However, CTX III did not generate reactive oxygen species (ROS) and antioxidants, including N-acetylcysteine and catalase, did not block CTX III-induced apoptosis in K562 cells. Modulation of Bax, Bcl-X(L), and the Endo G proteins, release of mitochondrial cytochome c, and activation of caspase-3 and -9 all are involved in the CTX III-triggered apoptotic process in human leukemia K562 cells.

Rol de las proteinas desacoplantes UCP1, UCP2 y UCP3 en el gasto energetico, diabetes tipo 2 y obesidad: Sinergismo con la tiroides / Role of uncoupling proteins UCP1, UCP2 and UCP3 in energy balance, type 2 diabetes and obesity: Synergism with the thyroid

La formación de tejido graso resulta del balance entre la ingestión y el consumo de energía, lo cual destaca la importancia del estudio de los factores que controlan el gasto energético. La hormona tiroidea es conocida desde hace tiempo como el principal regulador del metabolismo basal, a través de la estimulación del consumo de oxígeno en las células. El descubrimiento de la grasa parda y de la proteína desacoplante-1 (UCP1) demostró la importancia de este tejido para la regulación del consumo energético em mamíferos. La proteína desacoplante-2 (UCP2) se expresa en muchos tejidos y tendría una acción protectora de la función celular, al preservar el potencial de membrana afectado por el superóxido. La proteína desacoplante- 3 (UCP3) estaría vinculada a la producción de calor, facilitando la combustión de ácidos grasos en la cadena respiratoria mitocondrial, pero no parece participar en el control del gasto energético. El exceso de UCP3 em ratones transgénicos disminuyó la grasa corporal y aumentó la sensibilidad a la insulina seguido de hipoglucemia, sugiriendo así un futuro, hipotético uso de esta proteína en la diabetes 2 y en la obesidad. Los estudios que se realizan sobre estas proteínas y sobre hormonas del tejido adiposo blanco como la leptina, adiponectina, resistina, de péptidos hipotalámicos como neuropéptido Y, CRF, hormona alfa-melanocítica y péptidos regulados por cocaína y anfetamina (CART), muestran resultados promisorios para una futura aplicación en el control del gasto energético en humanos y con ello en la prevención o el tratamiento de la obesidad y la diabetes tipo 2.

Toxicity of PCB 1232 on mitochondria of fish Arius caelatus (Valenciennes).

Mitochondrial proteins and phospholipids were estimated and SDH, Na(+)-K(+)-ATPase and Mg(2+)-ATPase activities were analysed in the gill, liver and heart tissues of PCB 1232 (sublethal doses) treated fish A. caelatus. Protein and phospholipids were found to be decreased significantly and SDH, Na(+)-K(+)-ATPase, Mg(2+)-ATPase and other enzyme systems displayed an inverse relationship with PCB dosage. Statistical analysis was carried out to indicate the relationship between sublethal doses of varying concentration and the activities of the enzyme systems involved in energy metabolism. The studies indicated impairment in mitochondrial functions.

Qualitative study of three cell culture methods / 华中科技大学学报（医学）（英德文版）

Primary rat hepatocytes were cultured using different in vitro models and the enzyme leakage, albumin secretion, and cytochrome P450 1A (CYP 1A) activity were observed. The results showed that the level of LDH was decreased over time in culture. However, on day 5, LDH showed a significant increase in monolayer culture (MC) while after day 8 no LDH was detectable in sandwich culture (SC). The levels of AST and ALT did not change significantly over the investigated time. The CYP 1A activity was gradually decreased in a time-dependent manner in MC and SC. The decline of CYP 1A was faster in MC than in SC. This effect was partially reversed by using cytochrome P450 (CYP450) inducer such as Omeprazol and 3-methylcholanthrene (3-MC) and the CYP 1A induction was always higher in MC than in SC. In bioreactor basic CYP 1A activity was preserved over 2 weeks and the highest albumin production was observed in bioreactor followed by SC and MC. Taken together, it was indicated each investigated model had its advantages and disadvantages. It was also underlined that various in vitro models may address different questions.