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1.
Cancer Sci ; 115(4): 1073-1084, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279834

RESUMO

In CD70-expressing tumors, the interaction of CD70 on tumor cells with its lymphocyte receptor, CD27, is thought to play a role in immunosuppression in the tumor microenvironment and elevated serum levels of soluble CD27 (sCD27). Previous studies showed that CD70 is expressed in nasopharyngeal carcinoma (NPC), an Epstein-Barr virus (EBV)-related malignancy. However, the association between intratumoral CD70/CD27 expression and serum levels of sCD27 in NPC remains unclear. In the present study, we show that CD70 is primarily expressed by tumor cells in NPC and that CD27-positive lymphocytes infiltrate around tumor cells. NPC patients with CD27-positive lymphocytes had significantly better prognosis than patients lacking these cells. In addition, high CD70 expression by tumor cells tended to be correlated with shorter survival in NPC patients with CD27-positive lymphocytes. Serum sCD27 levels were significantly increased in patients with NPC and provided good diagnostic accuracy for discriminating patients from healthy individuals. The concentration of serum sCD27 in patients with CD70-positive NPC with CD27-positive lymphocytes was significantly higher than in patients with tumors negative for CD70 and/or CD27, indicating that the intratumoral CD70/CD27 interaction boosts the release of sCD27. Furthermore, positive expression of CD70 by NPC cells was significantly correlated with EBV infection. Our results suggest that CD70/CD27-targeted immunotherapies may be promising treatment options and that sCD27 may become an essential tool for evaluating the applicability of these therapies by predicting the intratumoral CD70/CD27 interaction in NPC.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Biomarcadores , Ligante CD27/metabolismo , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Carcinoma Nasofaríngeo , Microambiente Tumoral , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
2.
Clin Exp Nephrol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888720

RESUMO

BACKGROUND: Tonsillectomy with steroid pulse therapy (TSP) and tonsillectomy monotherapy (T) have improved the prognosis of patients with immunoglobulin A nephropathy (IgAN). However, a consensus has not been reached on the best treatment for these patients. This study aimed to compare the efficacies of TSP and T. METHODS: Data of patients with IgAN who received TSP or T were retrospectively analyzed. The exclusion criterion was a serum creatinine level > 1.5 mg/dL. The clinical remission and renal survival rates were compared. RESULTS: Patients were divided into groups based on the treatment method: the TSP (n = 82) and T groups (n = 41). No significant differences were observed in patient characteristics, except for the observation period (TSP: 60 months, T: 113 months). The log-rank test revealed that the clinical remission rate was significantly higher in the TSP group than in the T group (p < 0.05). The superiority of TSP was also observed in the urinary protein excretion (> / = or < 1 g/day) of the two subgroups. According to the Cox proportional-hazards model, the treatment method and daily urinary protein extraction were independent factors affecting clinical remission. The 10-year renal survival rates in the TSP and T groups were 100% and 92.5%, respectively. The log-rank test revealed a tendency for a higher renal survival rate in the TSP group than in the T group (p = 0.09). CONCLUSION: The clinical remission rate was significantly higher with TSP than with T, regardless of urinary protein levels. TSP tended to have a better renal survival rate than T.

3.
Clin Otolaryngol ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950901

RESUMO

INTRODUCTION: Fluorine 18-fluoro-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) is commonly used for the staging of head and neck cancer. This study aimed to evaluate the correlation between 18F-FDG PET/CT, haematological parameters and prognosis in patients with advanced head and neck cancer. METHODS: This was a single-institutional retrospective study of 83 patients with advanced head and neck squamous cell carcinoma (HNSCC) who underwent 18F-FDG PET/CT imaging before initial treatment between 2014 and 2018. 18F-FDG PET/CT after treatment was performed in 57 patients. The prognostic parameters of the pre- and post-treatment maximum standardised uptake value (SUVmax), metabolic tumour volume (MTV), total lesion glycolysis (TLG) of primary tumours and haematological parameters were analysed to evaluate the association between overall survival (OS) and progression-free survival (PFS). RESULTS: Pre-MTV, pre-TLG and post-SUVmax were significantly associated with poor OS and PFS (p < 0.05). Haematological parameters, including pretreatment neutrophil/lymphocyte ratio and C-reactive protein/albumin ratio, were associated with 18F-FDG PET/CT parameters. In multivariate analysis, post-SUVmax was an independent prognostic factor for OS and PFS. CONCLUSION: A correlation between PET/CT metabolic and haematological parameters was observed. The volume and intensity of 18F-FDG uptake region, in addition to haematological parameters, are feasible markers for predicting the progression of HNSCC in daily practice. Further, post-SUVmax could be an independent parameter for predicting poor survival.

4.
Biochem Biophys Res Commun ; 684: 149141, 2023 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-37897908

RESUMO

The loss of skeletal muscle mass leads to various adverse conditions and shortened lifespan. The inhibition of myoblast proliferation is one of the causes that trigger muscle atrophy. Advanced glycation end products (AGEs) contribute to muscle atrophy. Since primary cilia are crucial organelles for proliferation, AGEs may inhibit primary cilia formation of myoblasts, thereby leading to impaired proliferation. Therefore, we aimed to clarify whether AGEs impeded the proliferation and formation of primary cilia of C2C12 skeletal muscle cells. AGE treatment inhibited the proliferation and formation of primary cilia. However, the inhibitor of the receptor for advanced glycosylation end products (RAGEs) abolished the inhibition of the proliferation and the primary cilia formation of C2C12 cells by AGEs, suggesting that AGEs cause these inhibitions through the RAGE pathway. In summary, our findings suggested that AGEs suppress the proliferation and formation of primary cilia of myoblasts through the RAGE pathway.


Assuntos
Cílios , Produtos Finais de Glicação Avançada , Humanos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Cílios/metabolismo , Mioblastos/metabolismo , Atrofia Muscular/metabolismo , Proliferação de Células
5.
Cancer Immunol Immunother ; 72(8): 2799-2812, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37173455

RESUMO

Brachyury is a transcription factor belonging to the T-box gene family and is involved in the posterior formation of the mesoderm and differentiation of chordates. As the overexpression of Brachyury is a poor prognostic factor in a variety of cancers, the establishment of Brachyury-targeted therapy would be beneficial for the treatment of aggressive tumors. Because transcription factors are difficult to treat with a therapeutic antibody, peptide vaccines are a feasible approach for targeting Brachyury. In this study, we identified Brachyury-derived epitopes that elicit antigen-specific and tumor-reactive CD4+ T cells that directly kill tumors. T cells recognizing Brachyury epitopes were present in patients with head and neck squamous cell carcinoma. Next, we focused on gemcitabine (GEM) as an immunoadjuvant to augment the efficacy of antitumor responses by T cells. Interestingly, GEM upregulated HLA class I and HLA-DR expression in tumor, followed by the upregulation of anti-tumor T cell responses. As tumoral PD-L1 expression was also augmented by GEM, PD-1/PD-L1 blockade and GEM synergistically enhanced the tumor-reactivity of Brachyury-reactive T cells. The synergy between the PD-1/PD-L1 blockade and GEM was also confirmed in a mouse model of head and neck squamous cell carcinoma. These results suggest that the combined treatment of Brachyury peptide with GEM and immune checkpoint blockade could be a promising immunotherapy against head and neck cancer.


Assuntos
Gencitabina , Neoplasias de Cabeça e Pescoço , Animais , Camundongos , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1 , Linhagem Celular Tumoral , Neoplasias de Cabeça e Pescoço/terapia , Imunoterapia/métodos , Epitopos
6.
Cancer Immunol Immunother ; 72(7): 2087-2098, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36811663

RESUMO

The engagement of CD27 on lymphocytes with its ligand, CD70, on tumors is believed to mediate tumor immune evasion and the elevation of serum soluble CD27 (sCD27) levels in patients with CD70-positive malignancies. We previously showed that CD70 is expressed in extranodal natural killer/T-cell lymphoma, nasal type (ENKL), an Epstein-Barr virus (EBV)-related malignancy. However, little is known about serum sCD27 expression and its association with the clinical characteristics of, and the CD27/CD70 interaction in, ENKL. In the present study, we show that serum sCD27 is significantly elevated in the sera of patients with ENKL. The levels of serum sCD27 provided excellent diagnostic accuracy for discriminating patients with ENKL from healthy subjects, correlated positively with the levels of other diagnostic markers (lactate dehydrogenase, soluble interleukin-2 receptor, and EBV-DNA), and decreased significantly following treatment. Elevated serum sCD27 levels also correlated significantly with advanced clinical stage and tended to correspond with shorter survival, in patients with ENKL. Immunohistochemistry indicated that CD27-positive tumor-infiltrating immune cells exist adjacent to CD70-positive lymphoma cells. In addition, serum sCD27 levels in patients with CD70-positive ENKL were significantly higher than those in patients with CD70-negative ENKL, suggesting that the intra-tumoral CD27/CD70 interaction boosts the release of sCD27 in serum. Furthermore, the EBV-encoded oncoprotein latent membrane protein 1 upregulated CD70 expression in ENKL cells. Our results suggest that sCD27 may serve as a novel diagnostic biomarker and also may serve as a tool for evaluating the applicability of CD27/CD70-targeted therapies by predicting intra-tumoral CD70 expression and CD27/CD70 interaction in ENKL.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma de Células T , Humanos , Ligante CD27 , Herpesvirus Humano 4/metabolismo , Biomarcadores , Células Matadoras Naturais/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral
7.
Am J Physiol Endocrinol Metab ; 322(5): E425-E435, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35344394

RESUMO

A single bout of exercise can potentiate the effect of insulin on skeletal muscle glucose uptake via activation of the AMPK-TBC1 domain family member 4 (TBC1D4) pathway, which suggests a positive correlation between AMPK activation and insulin sensitization. In addition, prolonged fasting in rodents is known to upregulate and thereby synergistically enhance the effect of exercise on muscle AMPK activation. Therefore, fasting may potentiate the insulin-sensitizing effect of exercise. In the present study, we mimicked exercise by in situ muscle contraction and evaluated the effect of a 36-h fast on muscle contraction-induced insulin sensitization. Male Wistar rats weighing 150-170 g were allocated to either a 36-h fasting or feeding group. The extensor digitorum longus (EDL) muscles were electrically contracted via the common peroneal nerve for 10 min followed by a 3-h recovery period. EDL muscles were dissected and incubated in the presence or absence of submaximal insulin. Our results demonstrated that acute muscle contraction and 36 h of fasting additively upregulated AMPK pathway activation. Insulin-stimulated muscle glucose uptake and site-specific TBC1D4 phosphorylation were enhanced by prior muscle contraction in 36-h-fasted rats, but not in fed rats. Moreover, enhanced insulin-induced muscle glucose uptake and Akt phosphorylation due to 36 h of fasting were associated with a decrease in tribbles homolog 3 (TRB3), a negative regulator of Akt activation. In conclusion, fasting and prior muscle contraction synergistically enhance insulin-stimulated TBC1D4 phosphorylation and glucose uptake, which is associated with augmented AMPK pathway activation in rodents.NEW & NOTEWORTHY In this study, we revealed that 36 h of fasting additively upregulated acute muscle contraction-induced AMPK pathway activation in rats. Besides, fasting and muscle contraction synergistically enhanced insulin-stimulated site-specific TBC1D4 phosphorylation and glucose uptake, which was associated with augmented AMPK pathway activation. These results contribute to understanding the regulation of muscle insulin sensitivity.


Assuntos
Proteínas Quinases Ativadas por AMP , Insulina , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Jejum , Proteínas Ativadoras de GTPase/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Insulina/farmacologia , Masculino , Contração Muscular , Músculo Esquelético/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar
8.
FASEB J ; 35(4): e21459, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33710687

RESUMO

Chronic muscle loading (overload) induces skeletal muscles to undergo hypertrophy and to increase glucose uptake. Although AMP-activated protein kinase (AMPK) reportedly serves as a negative regulator of hypertrophy and a positive regulator of glucose uptake, its role in overload-induced skeletal muscle hypertrophy and glucose uptake is unclear. This study aimed to determine whether AMPK regulates overload-induced hypertrophy and glucose uptake in skeletal muscles. To this end, skeletal muscle overload was induced through unilateral synergist ablations in wild-type (WT) and transgenic mice, expressing the dominant-negative mutation of AMPK (AMPK-DN). After 14 days, parameters, including muscle fiber cross-sectional area (CSA), glycogen level, and in vivo [3 H]-2-deoxy-D-glucose uptake, were assessed. No significant difference was observed in body weight or blood glucose level between the WT and AMPK-DN mice. However, the 14-day muscle overload activated the AMPK pathway in WT mice skeletal muscle, whereas this response was impaired in the AMPK-DN mice. Despite a normal CSA gain in each fiber type, the AMPK-DN mice demonstrated a significant impairment of overload-induced muscle glucose uptake and glycogenesis, compared to WT mice. Moreover, 14-day overload-induced changes in GLUT4 and HKII expression levels were reduced in AMPK-DN mice, compared to WT mice. This study demonstrated that AMPK activation is indispensable for overload-induced muscle glucose uptake and glycogenesis; however, it is dispensable for the induction of hypertrophy in AMPK-DN mice. Furthermore, the AMPK/GLUT4 and HKII axes may regulate overload-induced muscle glucose uptake and glycogenesis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismo , Hipertrofia/metabolismo , Músculos/metabolismo , Animais , Glicogênio/metabolismo , Camundongos Transgênicos , Músculo Esquelético/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo
9.
J Theor Biol ; 555: 111300, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36209900

RESUMO

A two-dimensional mathematical model for dynamics of endothelial cells in angiogenesis is investigated. Angiogenesis is a morphogenic process in which new blood vessels emerge from an existing vascular network. Recently a one-dimensional discrete dynamical model has been proposed to reproduce elongation, bifurcation, and cell motility such as cell-mixing during angiogenesis on the assumption of a simple two-body interaction between endothelial cells. The present model is its two-dimensional extension, where endothelial cells are represented as the ellipses with the two-body interactions: repulsive interaction due to excluded volume effect, attractive interaction through pseudopodia and rotation by contact. We show that the oblateness of ellipses and the magnitude of contact rotation significantly affect the shape of created vascular patterns and elongation of branches.


Assuntos
Células Endoteliais , Neovascularização Patológica , Humanos , Morfogênese , Movimento Celular , Modelos Teóricos , Neovascularização Fisiológica
10.
BMC Surg ; 22(1): 349, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36138405

RESUMO

BACKGROUND: In accordance with previous reports on the utility of polyethylene glycolic acid (PGA) felt and fibrin glue for postoperative pancreatic fistula (POPF), we usually perform distal pancreatectomy (DP) with a PGA felt reinforcement stapler when dissecting the pancreas and cover the stump with PGA felt and fibrin glue (the PPF method). In this study, we retrospectively analyzed our DP cases to compare the risk factors for POPF and the postoperative course of patients receiving the PPF method of treatment versus that of those receiving conventional treatment. METHODS: A total of 127 DP procedures performed in our department between January 2008 and June 2021 were retrospectively analysed. RESULTS: In the PPF method, grade B/C POPF rate tended to decrease, and POPF rate showed a significant decrease. The duration of drainage and the length of postoperative hospitalisation were also significantly shorter with the PPF method. The risk of grade B/C POPF significantly decreased with the PPF method if the pancreas was thick (> 13.5 mm) or the patients were obese. CONCLUSIONS: The PPF method is useful for POPF in DP and is particularly effective when a thick pancreas or obese patient is involved. Removing the drainage tube early in the PPF method may lead to early discharge.


Assuntos
Adesivo Tecidual de Fibrina , Fístula Pancreática , Humanos , Adesivo Tecidual de Fibrina/uso terapêutico , Glicolatos , Obesidade/cirurgia , Pâncreas/cirurgia , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Fístula Pancreática/cirurgia , Polietileno , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco
11.
BMC Surg ; 22(1): 55, 2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35152891

RESUMO

BACKGROUND: Prepancreatic portal vein (PPV) is a congenital anatomical variant of the portal vein (PV). PPVs are extremely rare and generally classified into two categories, prepancreatic preduodenal portal vein and prepancreatic postduodenal portal vein (PPPV). Prepancreatic preduodenal portal veins are rare, with approximately 100 reported cases globally; PPPVs are even more atypical, with less than 20 documented cases globally. Despite the extremely low occurrence, PPPV knowledge and recognition are important, especially for hepatobiliary-pancreatic (HBP) surgeries, such as pancreaticoduodenectomy (PD) for patients of a PPPV. Here, we report a case of PPPV and a literature review. CASE PRESENTATION: A 73-year-old-male with ampullary carcinoma underwent PD at our hospital. Preoperative enhanced CT revealed an abnormal L-shaped PV, identified as a PPPV. Both the PPPV and the postpancreatic "normal" superior mesenteric vein (SMV) divaricated from the SMV at the caudal side of the pancreas. A splenic vein and inferior mesenchymal vein flowed into the postpancreatic "normal" PV, which encircled the common bile duct and potentially flowed into the liver, forming a cavernous transformation at the hilar plate. During surgery, we attempted to isolate the PV from the pancreas and common bile duct. However, it was difficult to isolate from the pancreas. The PPPV was so fragile that bleeding from the PPPV became uncontrollable. To remove the tumor, we resected the PPPV and reconstructed a "normal" PV as an autogenous graft. To maintain intraoperative hepatic blood flow and avoid small bowel congestion, an antithrombogenic bypass catheter was placed between the SMV and umbilical vein during reconstruction. After surgery, several complications occurred, such as PV thrombosis and hyperammonemia. The patient was discharged on postoperative day 45. CONCLUSIONS: PPPV is a rare vascular variant but is easily diagnosed preoperatively due to its distinct shape on CT imaging. However, isolating the PPPV from the pancreas and bile duct is incredibly difficult and potentially associated with increased operative risks and postoperative complications. PV resection rather than isolation is a potential solution to reduce the risk of hemorrhage, even in the absence of invasion.


Assuntos
Neoplasias Pancreáticas , Veia Porta , Idoso , Humanos , Masculino , Veias Mesentéricas/cirurgia , Pâncreas , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Veia Porta/cirurgia
12.
Int J Mol Sci ; 23(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35163799

RESUMO

Endurance exercise induces various adaptations that yield health benefits; however, the underlying molecular mechanism has not been fully elucidated. Given that it has recently been accepted that inflammatory responses are required for a specific muscle adaptation after exercise, this study investigated whether toll-like receptor (TLR) 4, a pattern recognition receptor that induces proinflammatory cytokines, is responsible for exercise-induced adaptations in mouse skeletal muscle. The TLR4 mutant (TLR4m) and intact TLR4 control mice were each divided into 2 groups (sedentary and voluntary wheel running) and were housed for six weeks. Next, we removed the plantaris muscle and evaluated the expression of cytokines and muscle regulators. Exercise increased cytokine expression in the controls, whereas a smaller increase was observed in the TLR4m mice. Mitochondrial markers and mitochondrial biogenesis inducers, including peroxisome proliferator-activated receptor beta and heat shock protein 72, were increased in the exercised controls, whereas this upregulation was attenuated in the TLR4m mice. In contrast, exercise increased the expression of molecules such as peroxisome proliferator-activated receptor-gamma coactivator 1-alpha and glucose transporter 4 in both the controls and TLR4m mice. Our findings indicate that exercise adaptations such as mitochondrial biogenesis are mediated via TLR4, and that TLR4-mediated inflammatory responses could be involved in the mechanism of adaptation.


Assuntos
Treino Aeróbico/veterinária , Inflamação/genética , Lipopolissacarídeos/efeitos adversos , Músculo Esquelético/imunologia , Receptor 4 Toll-Like/genética , Adaptação Fisiológica , Animais , Citocinas/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Masculino , Camundongos , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/efeitos dos fármacos , Mutação , Biogênese de Organelas , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Condicionamento Físico Animal , Regulação para Cima
13.
Cancer Immunol Immunother ; 70(12): 3421-3434, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33866408

RESUMO

Identification of immunogenic tumor antigens, their corresponding T cell epitopes and the selection of effective adjuvants are prerequisites for developing effective cancer immunotherapies such as therapeutic vaccines. Murine double minute 2 (MDM2) is an E3 ubiquitin-protein ligase that negatively regulates tumor suppressor p53. Because MDM2 overexpression serves as a poor prognosis factor in various types of tumors, it would be beneficial to develop MDM2-targeted cancer vaccines. In this report, we identified an MDM2-derived peptide epitope (MDM232-46) that elicited antigen-specific and tumor-reactive CD4+ T cell responses. These CD4+ T cells directly killed tumor cells via granzyme B. MDM2 is expressed in head and neck cancer patients with poor prognosis, and the T cells that recognize this MDM2 peptide were present in these patients. Notably, Nutlin-3 (MDM2-p53 blocker), inhibited tumor cell proliferation, was shown to augment antitumor T cell responses by increasing MDM2 expression, HLA-class I and HLA-DR through class II transactivator (CIITA). These results suggest that the use of this MDM2 peptide as a therapeutic vaccine combined with MDM2 inhibitors could represent an effective immunologic strategy to treat cancer.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos de Neoplasias/imunologia , Linfócitos T CD4-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Proteínas Proto-Oncogênicas c-mdm2/imunologia , Animais , Vacinas Anticâncer/imunologia , Linhagem Celular , Proliferação de Células/fisiologia , Antígenos HLA-DR/imunologia , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Imunoterapia/métodos , Camundongos , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/imunologia
14.
Biochem Biophys Res Commun ; 527(1): 146-152, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32446358

RESUMO

The mitochondrial translation process, in which mitochondrial DNA (mtDNA)-encoded genes are translated into their corresponding proteins, is crucial for mitochondrial function, biogenesis, and integrity. This process is divided into four phases-initiation, elongation, termination, and mitoribosome recycling-which are regulated by specific translation factors, including mitochondrial initiation factor 2 and 3 (mtIF2 and mtIF3), mitochondrial elongation factor Tu, Ts, and G1 (mtEFTu, mtEFTs, and mtEFG1), mitochondrial translational release factor 1-like (mtRF1L), and mitochondrial recycling factor 1 and 2 (mtRRF1 and mtRRF2). Muscle denervation downregulates mitochondrial biomass and induces skeletal muscle atrophy. However, it is unknown whether denervation affects the expression of mitochondrial translation factors in skeletal muscle. In this study, we hypothesized that denervation decreases the expression of mitochondrial translation factors. Therefore, we investigated the effect of muscle denervation on mitochondrial protein and mitochondrial translation factor expression in soleus muscle after surgery. Denervation induced muscle atrophy and activated the ubiquitin-proteasome pathway in soleus muscle. Additionally, muscle denervation decreased the expression of mitochondrial translation factors as well as nuclear DNA and mtDNA-encoded mitochondrial proteins in soleus muscle. Further, a correlation was found between the expression of mitochondrial translation factors and mtDNA-encoded proteins three and seven days after denervation. Taken together, these results demonstrated that the denervation-induced decrease in mitochondrial biogenesis corresponded with changes in mitochondrial translation factors in murine skeletal muscle, providing novel molecular-level insight into the effects of muscle denervation on the mitochondrial translation process.


Assuntos
Mitocôndrias Musculares/metabolismo , Proteínas Mitocondriais/metabolismo , Denervação Muscular , Músculo Esquelético/metabolismo , Biossíntese de Proteínas , Animais , DNA Mitocondrial/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atrofia Muscular/metabolismo
15.
Biochem Biophys Res Commun ; 528(3): 612-619, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32505344

RESUMO

Substantial evidence has linked dehydroepiandrosterone (DHEA) levels to the anti-obesity and anti-diabetic effects of exercise. While 5'-adenosine monophosphate-activated protein kinase (AMPK) is a negative regulator of adipocyte differentiation and lipid accumulation, activation of mammalian target of rapamycin complex 1 (mTORC1), which is inhibited by AMPK, is required for adipocyte differentiation and positively regulates lipid accumulation. DHEA treatment activates the AMPK pathway in C2C12 myotubes. Hence, DHEA addition to preadipocytes and adipocytes might activate AMPK and inhibit mTORC1, resulting in the inhibition of adipogenesis and lipid accumulation. Therefore, we investigated the effect of DHEA on the AMPK pathway, mTORC1 activity, adipocyte differentiation, and lipid accumulation in 3T3-L1 cells. DHEA suppressed lipid accumulation and adipogenic marker expression during differentiation. It also activated AMPK signaling in preadipocytes and adipocytes and suppressed mTORC1 activity during differentiation. These results suggest that the activation of the AMPK pathway and inhibition of mTORC1 activity may mediate the anti-obesity effect of DHEA, providing novel molecular-level insights into its physiological functions.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Desidroepiandrosterona/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/citologia , Adipogenia/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Desidroepiandrosterona/metabolismo , Ativação Enzimática/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Camundongos , Obesidade/metabolismo , Obesidade/prevenção & controle , Transdução de Sinais/efeitos dos fármacos
16.
J Cardiovasc Electrophysiol ; 31(7): 1597-1605, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32367545

RESUMO

INTRODUCTION: There are limited data focusing on pulmonary vein (PV) narrowing following ablation using a visually guided laser balloon (VGLB). We sought to assess the frequency and predictors of PV narrowing after VGLB ablation. METHODS AND RESULTS: Patients with paroxysmal atrial fibrillation treated with VGLB were screened. Study participants underwent contrast-enhanced computed tomography (CT) scanning before and 6 months after the procedure. We defined 25% to 49%, 50% to 74%, and 75% to 100% reduction in PV cross-sectional area as mild, moderate, and severe narrowing, respectively. Of 146 PVs in 38 patients analyzed, severe narrowing developed in two right superior and one right inferior PV. Moderate or severe narrowing occurred in 40 veins (27% of all PVs, 50% of the right superior, 22% of the right inferior, 21% of the left superior, and 14% of the left inferior PV). In PVs with moderate-severe narrowing, the baseline orifice area was significantly larger (4.1 [interquartile range, 3.2-4.8] vs 2.5 [1.9-3.3] cm2 , P < .0001), the narrowest region of stenosis was significantly more distal into the vessel (1.9 [0.7-2.9] vs 0 [0-1.7] mm from the orifice, P = .0006) and the total amount of energy delivered per vein was significantly greater (5190 ± 970 vs 4626 ± 1573 J, P = .018) than in PVs with mild or no significant narrowing. The baseline orifice area independently predicted moderate-severe narrowing in multivariate analysis (odds ratio, 1.8 [1.3-2.5] per 1 cm2 increase, P = .0003). No patient exhibited any signs or symptoms of PV stenosis. CONCLUSIONS: Baseline PV orifice area, ablating distally inside the veins, and total amount of laser energy are associated with PV narrowing after VGLB ablation.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Terapia a Laser , Veias Pulmonares , Estenose de Veia Pulmonar , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Humanos , Terapia a Laser/efeitos adversos , Razão de Chances , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Estenose de Veia Pulmonar/diagnóstico por imagem , Estenose de Veia Pulmonar/etiologia , Estenose de Veia Pulmonar/cirurgia , Resultado do Tratamento
17.
J Cardiovasc Electrophysiol ; 31(10): 2592-2599, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32666561

RESUMO

BACKGROUND: Recent studies have shown the improvement in long-term effectiveness with standardized pulmonary vein isolation (PVI) aimed at creating durable and contiguous lesions with VISITAG SURPOINT (VS) in paroxysmal atrial fibrillation (PAF). OBJECTIVE: We aimed to assess efficacy of PVI alone strategy using VS in non-PAF patients and evaluate factors associated with corresponding clinical outcomes. METHODS: Consecutive patients who underwent PVI for persistent/long-standing persistent AF between May 2017 to July 2019 were studied retrospectively. PVI was performed with 30-50 W guided by VS (posterior target: 400-500, anterior target: 500). Left atrial voltage maps were created during atrial pacing after PVI. RESULTS: A total of 140 patients (119 males, age 62 ± 10 years, long-standing persistent AF: 35) were included and followed for median of 454 days. No adverse events were reported in any patients during periprocedural and follow-up period of up to 28 months. Kaplan-Meier analysis estimated that freedom from atrial tachycardia or AF (AT/AF) without antiarrhythmics at 1-year was 70%. Radiofrequency delivery with higher power was associated with increased first-pass isolation rate, but not with freedom from AT/AF. In multivariate analysis, long-standing persistent AF and % low-voltage zone (%LVZ) were independent predictors of clinical outcome. The best cut-off value of %LVZ for predicting AT/AF recurrence was 3.24%. Freedom from AT/AF was 88% in patients with persistent AF and %LVZ < 3.24%, while 27% in those with long-standing persistent AF and %LVZ ≥ 3.24%. CONCLUSIONS: PVI alone using VS was associated with excellent 1-year success in patients with persistent AF and %LVZ < 3.24%, but was insufficient in those with long-standing persistent AF and/or %LVZ ≥ 3.24%.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Criança , Humanos , Masculino , Veias Pulmonares/cirurgia , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
18.
J Bone Miner Metab ; 38(5): 631-638, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32350615

RESUMO

INTRODUCTION: Disuse-induced bone loss is caused by a suppression of osteoblastic bone formation and an increase in osteoclastic bone resorption. There are few data available for the effects of environmental conditions, i.e., atmospheric pressure and/or oxygen concentration, on osteoporosis. This study examined the effects of mild hyperbaric oxygen at 1317 hPa with 40% oxygen on unloading-induced osteoporosis. MATERIALS AND METHODS: Eighteen 8-week old male Wistar rats were randomly divided into three groups: the control for 21 days without unloading and mild hyperbaric oxygen (NOR, n = 6), the unloading for 21 days and recovery for 10 days without mild hyperbaric oxygen (HU + NOR, n = 6), and the unloading for 21 days and recovery for 10 days with mild hyperbaric oxygen (HU + MHO, n = 6). RESULTS: The cortical thickness and trabecular bone surface area were decreased in the HU + NOR group compared to the NOR group. There were no differences between the NOR and HU + MHO groups. Osteoclast surface area and Sclerostin (Sost) mRNA expression levels were decreased in the HU + MHO group compared to the HU + NOR group. These results suggested that the loss of the cortical and trabecular bone is inhibited by mild hyperbaric oxygen, because of an inhibition of osteoclasts and enhancement of bone formation with decreased Sost expression. CONCLUSIONS: We conclude that exposure to mild hyperbaric oxygen partially protects from the osteoporosis induced by hindlimb unloading.


Assuntos
Elevação dos Membros Posteriores/fisiologia , Oxigenoterapia Hiperbárica , Osteoporose/fisiopatologia , Osteoporose/terapia , Animais , Peso Corporal , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Osso Esponjoso/patologia , Osso Esponjoso/fisiopatologia , Osso Cortical/patologia , Osso Cortical/fisiopatologia , Marcadores Genéticos/genética , Lâmina de Crescimento/patologia , Masculino , Osteocalcina/genética , Osteocalcina/metabolismo , Osteoclastos/patologia , Osteoporose/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar
19.
Cell Immunol ; 341: 103925, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31088610

RESUMO

IgA nephropathy (IgAN) is a tonsil-related disease. We previously showed that oligodeoxynucleotides with CpG (CpG-ODN) and B-cell activation factor (BAFF) are involved in hyperproduction of IgA from tonsillar mononuclear cells of patients with IgAN (IgAN-TMCs). In this study, we focused on a proliferation-inducing ligand (APRIL), homologous to BAFF. IgAN-TMCs produced more APRIL than non IgAN-TMCs in the presence of both CpG-ODN and control-ODN. TLR9 expression was higher in B-cells of IgAN-TMCs, and treatment with CpG-ODN enhanced transmembrane activator and CAML interactor (TACI) expression. IgA production from IgAN-TMCs was inhibited by APRIL neutralization antibody or TACI blocking antibody, and enhanced by co-treatment of APRIL and CpG-ODN. Serum APRIL levels were higher in patients with IgAN, and decreased after tonsillectomy. These findings suggest that APRIL is involved in the hyperproduction of IgA from IgAN-TMCs, and that CpG-ODN enhanced APRIL-induced IgA production by increasing TACI expression on B-cells of IgAN-TMCs.


Assuntos
Linfócitos B/imunologia , Glomerulonefrite por IGA/genética , Tonsila Palatina/imunologia , Proteína Transmembrana Ativadora e Interagente do CAML/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/farmacologia , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Regulação da Expressão Gênica , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/patologia , Glomerulonefrite por IGA/cirurgia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/farmacologia , Tonsila Palatina/patologia , Tonsila Palatina/cirurgia , Transdução de Sinais , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/imunologia , Tonsilectomia , Proteína Transmembrana Ativadora e Interagente do CAML/antagonistas & inibidores , Proteína Transmembrana Ativadora e Interagente do CAML/imunologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia
20.
J Cardiovasc Electrophysiol ; 30(6): 827-835, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30843306

RESUMO

BACKGROUND: Mitral valve prolapse (MVP) is a common valve condition and has been associated with sudden cardiac death. Premature ventricular contractions (PVCs) from the papillary muscles (PMs) may play a role as triggers for ventricular fibrillation (VF) in these patients. OBJECTIVES: To characterize the electrophysiological substrate and outcomes of catheter ablation in patients with MVP and PM PVCs. METHODS: Of 597 patients undergoing ablation of ventricular arrhythmias during the period 2012-2015, we identified 25 patients with MVP and PVCs mapped to the PMs (64% female). PVC-triggered VF was the presentation in 4 patients and a fifth patient died suddenly during follow-up. The left ventricle ejection fraction (LVEF) was 50.5% ± 11.8% and PVC burden was 24.4% ± 13.1%. A cardiac magnetic resonance imaging was performed in nine cases and areas of late gadolinium enhancement were found in four of them. A detailed LV voltage map was performed in 11 patients, three of which exhibited bipolar voltage abnormalities. Complete PVC elimination was achieved in 19 (76%) patients and a significant reduction in PVC burden was observed in two (8%). In patients in which the ablation was successful, the PVC burden decreased from 20.4% ± 10.8% to 6.3% ± 9.5% (P = 0.001). In 5/6 patients with depressed LVEF and successful ablation, the LV function improved postablation. No significant differences were identified between patients with and without VF. CONCLUSIONS: PM PVCs are a source of VF in patients with MVP and can induce PVC-mediated cardiomyopathy that reverses after PVC suppression. Catheter ablation is highly successful with more than 80% PVC elimination or burden reduction.


Assuntos
Ablação por Cateter , Prolapso da Valva Mitral/complicações , Valva Mitral/fisiopatologia , Músculos Papilares/cirurgia , Fibrilação Ventricular/prevenção & controle , Complexos Ventriculares Prematuros/cirurgia , Potenciais de Ação , Adulto , Idoso , Ablação por Cateter/efeitos adversos , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Prolapso da Valva Mitral/diagnóstico por imagem , Prolapso da Valva Mitral/fisiopatologia , Músculos Papilares/diagnóstico por imagem , Músculos Papilares/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Volume Sistólico , Fatores de Tempo , Resultado do Tratamento , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/fisiopatologia , Função Ventricular Esquerda , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/etiologia , Complexos Ventriculares Prematuros/fisiopatologia , Adulto Jovem
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