Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
3.
Biomimetics (Basel) ; 9(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38534836

RESUMO

This research introduces an advanced robotic finger designed for future generalist robots, closely mimicking the natural structure of the human finger. The incorporation of rarely discussed anatomical structures, including tendon sheath, ligaments, and palmar plates, combined with the usage of anatomically proven 3D models of the finger, give rise to the highly accurate replication of human-like soft mechanical fingers. Benefiting from the accurate anatomy of muscle insertions with the utilization of Shape Memory Alloy (SMA) wires' muscle-like actuation properties, the bonding in-between the flexor tendons and extensor tendons allows for the realization of the central and lateral band of the finger anatomy. Evaluated using the computer vision method, the proposed robotic finger demonstrates a range of motion (ROM) equivalent to 113%, 87% and 88% of the human dynamic ROM for the DIP, PIP and MCP joints, respectively. The proposed finger possesses a soft nature when relaxed and becomes firm when activated, pioneering a new approach in biomimetic robot design and offering a unique contribution to the future of generalist humanoid robots.

4.
Pharmacotherapy ; 43(12): 1317-1326, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37772313

RESUMO

STUDY OBJECTIVE: The effects of the sodium-dependent glucose transporter-2 inhibitor ipragliflozin were compared with metformin in a previous study, which revealed that ipragliflozin reduced visceral fat content by 12%; however, the underlying mechanism was unclear. Therefore, this sub-analysis aimed to compare metabolomic changes associated with ipragliflozin and metformin that may contribute to their biological effects. DESIGN: A sub-analysis of a randomized controlled study. SETTING: Chiba University Hospital and ten hospitals in Japan. PATIENTS: Fifteen patients with type 2 diabetes in the ipragliflozin group and 15 patients with type 2 diabetes in the metformin group with matching characteristics, such as age, sex, baseline A1C, baseline visceral fat area, smoking status, and concomitant medication. INTERVENTIONS: Ipragliflozin 50 mg or metformin 1000 mg daily. MEASUREMENTS: The clinical data were reanalyzed, and metabolomic analysis of serum samples collected before and 24 weeks after drug administration was performed using capillary electrophoresis time-of-flight mass spectrometry. MAIN RESULTS: The reduction in the mean visceral fat area after 24 weeks of treatment was significantly larger (p = 0.002) in the ipragliflozin group (-19.8%) than in the metformin group (-2.5%), as were the subcutaneous fat area and body weight. The A1C and blood glucose levels decreased in both groups. Glutamic pyruvic oxaloacetic transaminase, γ-glutamyl transferase, uric acid, and triglyceride levels decreased in the ipragliflozin group. Low-density lipoprotein cholesterol levels decreased in the metformin group. After ipragliflozin administration, N2-phenylacetylglutamine, inosine, guanosine, and 1-methyladenosine levels increased, whereas galactosamine, glucosamine, 11-aminoundecanoic acid, morpholine, and choline levels decreased. After metformin administration, metformin, hypotaurine, methionine, methyl-2-oxovaleric acid, 3-nitrotyrosine, and cyclohexylamine levels increased, whereas citrulline, octanoic acid, indole-3-acetaldehyde, and hexanoic acid levels decreased. CONCLUSIONS: Metabolites that may affect visceral fat reduction were detected in the ipragliflozin group. Studies are required to further elucidate the underlying mechanisms.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Metformina/uso terapêutico , Hipoglicemiantes/efeitos adversos , Japão , Hemoglobinas Glicadas , Gordura Intra-Abdominal/metabolismo , Glicemia , Quimioterapia Combinada , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
5.
J Diabetes Investig ; 14(12): 1419-1422, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37715448

RESUMO

Mitochondrial dysfunction causes maternally inherited deafness and diabetes (MIDD). Herein, we report improved glycemic control in a 47-year-old Japanese woman with MIDD using imeglimin without major adverse effects. Biochemical tests and metabolome analysis were performed before and after imeglimin administration. Blood glucose level fluctuations were determined. Sulfonylureas, dipeptidyl peptidase-4 inhibitors (DPP4is), and sodium glucose transporter-2 inhibitors (SGLT2i) were administered to evaluate the efficacy of their combination with imeglimin. Imeglimin decreased the HbA1c and ammonia levels and increased the time-in-range, C-peptide reactivity, and glucagon level. Elevated citrulline and histamine levels were decreased by imeglimin. The hypoglycemic effect was not enhanced by imeglimin when combined with sulfonylurea or DPP4i, but the blood glucose level was improved when combined with SGLT2i. Imeglimin improved glucose concentration-dependent insulin secretion and maximized the insulin secretory capacity by improving mitochondrial function and glutamine metabolism and urea circuit abnormalities by promoting glucagon secretion. Imeglimin could improve glycemic control in MIDD.


Assuntos
Surdez , Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Inibidores do Transportador 2 de Sódio-Glicose , Feminino , Humanos , Pessoa de Meia-Idade , Glicemia/análise , Glucagon , Controle Glicêmico , Herança Materna , Hipoglicemiantes/uso terapêutico , Surdez/tratamento farmacológico , Surdez/induzido quimicamente , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos
6.
Anticancer Res ; 43(6): 2455-2465, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37247906

RESUMO

BACKGROUND/AIM: Primary effusion lymphoma (PEL) is classified as a rare non-Hodgkin's B-cell lymphoma that is caused by Kaposi's sarcoma-associated herpesvirus (KSHV); PEL cells are latently infected with KSHV. PEL is frequently resistant to conventional chemotherapies. Therefore, the development of novel therapeutic agents is urgently required. Nigericin, a H+ and K+ ionophore, possesses unique pharmacological effects. However, the effects of nigericin on PEL cells remain unknown. MATERIALS AND METHODS: We examined the cytotoxic effects of the K+ ionophores, nigericin, nonactin, and valinomycin, on various B-lymphoma cells including PEL. We also evaluated ionophore-induced changes in signaling pathways involved in KSHV-induced oncogenesis. Moreover, the effects of nigericin on mitochondrial membrane potential and viral reactivation in PEL were analyzed. RESULTS: Although the three tested ionophores inhibited the proliferation of several B-lymphoma cell lines, nigericin inhibited the proliferation of PEL cells compared to KSHV-negative cells. In PEL cells, nigericin disrupted the mitochondrial membrane potential and caused the release of cytochrome c, which triggered caspase-9-mediated apoptosis. Nigericin also induced both an increase in phosphorylated p38 MAPK and proteasomal degradation of ß-catenin. Combination treatment of nigericin with the p38 MAPK inhibitor SB203580 potentiated the cytotoxic effects towards PEL cells, compared to either compound alone. Meanwhile, nigericin did not influence viral replication in PEL cells. CONCLUSION: Nigericin induces apoptosis in PEL cells by mitochondrial dysfunction and down-regulation of Wnt/ß-catenin signaling. Thus, nigericin is a novel drug candidate for treating PEL without the risk of de novo KSHV infection.


Assuntos
Antineoplásicos , Herpesvirus Humano 8 , Linfoma de Efusão Primária , Humanos , Linfoma de Efusão Primária/tratamento farmacológico , Linfoma de Efusão Primária/patologia , Nigericina/metabolismo , Nigericina/farmacologia , Nigericina/uso terapêutico , beta Catenina/metabolismo , Membranas Mitocondriais/metabolismo , Membranas Mitocondriais/patologia , Linhagem Celular Tumoral , Apoptose , Antineoplásicos/farmacologia , Herpesvirus Humano 8/fisiologia , Mitocôndrias , Ionóforos/metabolismo , Ionóforos/farmacologia , Ionóforos/uso terapêutico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Cancers (Basel) ; 13(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34830830

RESUMO

(1) Background: multiple myeloma patients have benefited from bortezomib therapy, though it has often been discontinued owing to diarrhea. The objective of this study was to verify serum bortezomib concentration in the emergence of diarrhea. (2) Methods: this prospective, observational case-control, and monocentric study was performed with an approval by the Ethics Committee of Kumamoto University Hospital in 2015 (No. 1121) from February 2015 to April 2017. (3) Results: twenty-four patients with bortezomib therapy were recruited; eight patients (33.3%) developed diarrhea at day 3 as median. Median measured trough bortezomib concentration at 24 h after first or second dose for patients with or without diarrhea was 0.87 or 0.48 ng/mL, respectively (p = 0.04, Wilcoxon signed rank test). Receiver operation characteristic (ROC) analysis produced the cut-off concentration of 0.857 ng/mL (area under the ROC curve of 0.797, sensitivity of 0.625, specificity of 0.875). The survival curves between patients with and without diarrhea were similar (p = 0.667); those between patients with higher and lower concentration than median value (0.61 ng/mL) were also similar (p = 0.940). (4) Conclusions: this study indicated the possible involvement of serum bortezomib concentration in the emergence of diarrhea in bortezomib therapy in patients with multiple myeloma.

8.
Diabetes Ther ; 12(5): 1415-1427, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33738773

RESUMO

INTRODUCTION: Sodium glucose co-transporter 2 (SGLT2) inhibitors are widely used in the management of type 2 diabetes mellitus; they prevent cardiovascular events and reduce fat mass. However, little is known about the effects of SGLT2 inhibitors on type 1 diabetes mellitus as an adjuvant to insulin therapy. Therefore, we aimed to elucidate the effects of SGLT2 inhibitors on body composition of patients with type 1 diabetes mellitus and assess blood glucose variability. METHODS: A single-center, single-arm, prospective, interventional study was performed on Japanese patients with type 1 diabetes mellitus who were not administered SGLT2 inhibitors prior to this study. These patients were equipped with flash glucose monitoring (FGM) and administered ipragliflozin 50 mg daily. Body composition was evaluated using bioelectrical impedance analysis, and glycemic variabilities were assessed using FGM before and after SGLT2 inhibitor treatment. RESULTS: After 52 weeks of treatment, the total fat mass tended to be reduced (- 9.10% from baseline, P = 0.098). In addition, skeletal muscle mass also decreased (- 2.98% from baseline, P = 0.023). Although the basal insulin dose was reduced, SGLT2 inhibitors decreased HbA1c levels. FGM revealed that glycemic variabilities were also reduced, and time within the target glucose range increased (51.7% vs. 62.5%, P = 0.004). CONCLUSION: SGLT2 inhibitors have beneficial effects on glycemic variabilities and fat mass reductions in patients with type 1 diabetes mellitus. However, loss of skeletal muscle is a major concern; therefore, caution is required when using SGLT2 inhibitors in lean patients with type 1 diabetes mellitus. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trial Registry (UMIN000042407).

9.
Diabetes Ther ; 12(1): 183-196, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33098565

RESUMO

INTRODUCTION: To compare the effects of ipragliflozin, a sodium-glucose transporter 2 inhibitor, with those of metformin on visceral fat (as well as muscles and bones) in Japanese elderly patients with type 2 diabetes (T2D), we conducted a sub-analysis of a prospective, multicenter, blinded-endpoint randomized-controlled study. METHODS: In total, 103 patients with T2D (body mass index ≥ 22 kg/m2; glycated hemoglobin, 7-10%) and being treated with sitagliptin (a dipeptidyl peptidase-4 inhibitor) were included and randomized to receive ipragliflozin or metformin. The primary outcome was the change in visceral fat area measured using computed tomography 24 weeks following treatment. The secondary outcomes included changes in subcutaneous and total fat area, muscle volume, bone density measured using computed tomography, handgrip strength, bone markers, plasma glucose, insulin, homeostasis model assessment (HOMA)2-beta, HOMA2-R, glycated hemoglobin, lipid panel, uric acid, blood pressure, adiponectin, and high-sensitivity C-reactive protein. All patients aged 65-74 years were selected for sub-analysis. RESULTS: The sub-analysis included 15 and 14 patients in the ipragliflozin and metformin groups, respectively. The patients' backgrounds were well balanced. Visceral fat area reduction was greater in the ipragliflozin group than in the metformin group (- 10.58% vs. - 6.93%; P = 0.034). There were significant differences in the changes in bone absorption markers, uric acid, and total cholesterol levels between the groups. CONCLUSION: Ipragliflozin significantly reduced the visceral fat area compared with metformin when added to sitagliptin in elderly patients with T2D. Long-term and large-scale studies are required to elucidate whether ipragliflozin is suitable for elderly patients. TRIAL REGISTRATION: The study was registered at https://www.umin.ac.jp/ctr/ (UMIN-ID: UMIN 000015170).

10.
J Diabetes Investig ; 12(2): 200-206, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32623839

RESUMO

AIMS/INTRODUCTION: Recent randomized clinical trials have suggested that sodium-glucose cotransporter 2 inhibitors might reduce cardiovascular events and heart failure, and have renal protective effects. Despite these remarkable benefits, the effects of sodium-glucose cotransporter 2 inhibitors on bone and muscle are unclear. MATERIALS AND METHODS: A subanalysis of a randomized controlled study was carried out to evaluate the effects of the sodium-glucose cotransporter 2 inhibitor, ipragliflozin, versus metformin on bone and muscle in Japanese patients with type 2 diabetes mellitus (baseline body mass index ≥22 kg/m2 and hemoglobin A1c 7-10%) who were already receiving sitagliptin. These patients were randomly administered ipragliflozin 50 mg or metformin 1,000-1,500 mg daily. The effects of these medications on the bone formation marker, bone alkali phosphatase; the bone resorption marker, tartrate-resistant acid phosphatase 5b (TRACP-5b); handgrip strength; abdominal cross-sectional muscle area; and bone density of the fourth lumbar vertebra were evaluated. RESULTS: After 24 weeks of treatment, the changes in bone density of the fourth lumbar vertebra, handgrip strength and abdominal cross-sectional muscle area were not significantly different between the two groups. However, TRACP-5b levels increased in patients treated with ipragliflozin compared with patients treated with metformin (median 11.94 vs -10.30%, P < 0.0001), showing that ipragliflozin can promote bone resorption. CONCLUSIONS: There were no adverse effects on bone or muscle when sitagliptin was used in combination with either ipragliflozin or metformin. However, ipragliflozin combination increased the levels of TRACP-5b. A long-term study is required to further understand the effects of this TRACP-5b increase caused by ipragliflozin.


Assuntos
Osso e Ossos/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/uso terapêutico , Metformina/uso terapêutico , Músculos/efeitos dos fármacos , Fosfato de Sitagliptina/uso terapêutico , Tiofenos/uso terapêutico , Adulto , Idoso , Biomarcadores/análise , Glicemia/análise , Osso e Ossos/patologia , Estudos Transversais , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Músculos/patologia , Prognóstico , Estudos Prospectivos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Adulto Jovem
11.
Diabetes Ther ; 12(1): 453-460, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33237553

RESUMO

INTRODUCTION: In Japan, several sodium glucose co-transporter 2 (SGLT2) inhibitors have been used for type 1 diabetes mellitus as an adjuvant therapy to insulin therapy; however, there are no clinical reports regarding the satisfaction of its use. Therefore, we conducted a survey among patients with type 1 diabetes undergoing treatment using an SGLT2 inhibitor. METHODS: This is a single-arm open-label prospective study including 24 patients with type 1 diabetes who were to be initiated on ipragliflozin treatment between March and August 2019. All participants provided written informed consent. They completed the Diabetes Treatment Satisfaction Questionnaire (DTSQ) for the survey and 3 months of observation after the administration of an SGLT2 inhibitor (50 mg of ipragliflozin), and changes from baseline diabetes treatment satisfaction were evaluated using modified DTSQ scores (five-step evaluation) and were analyzed. RESULTS: The average score for each question on DTSQ significantly increased [mean (standard deviation); 0.25 (0.25) vs 0.83 (0.77), P = 0.004]. Approximately 75% of the patients perceived an improvement in glycemic control over short periods of time. Finally, 54.2% of patients were highly satisfied and would recommend the SGLT2 inhibitor treatment [0.0 (0.0) vs. 0.92 (1.32), P < 0.001]. After the administration of ipragliflozin, reductions in body weight [24.0 (2.9) vs. 23.4 (2.9) kg/m2, P = 0.002], total insulin [39.1 (12.9) vs. 34.3 (12.5) units, P = 0.013], and glycated hemoglobin [7.77 (0.97) vs. 7.40 (0.86) %, P = 0.013] were observed, without any severe side effects. Improvements in glycemic variability indexes were observed through flash glucose monitoring. CONCLUSIONS: SGLT2 inhibitors may improve clinical treatment satisfaction by improving glycemic variability in patients with type 1 diabetes mellitus, while not inducing severe side effects with careful use. TRIAL REGISTRATION: This study is registered with the University Hospital Medical Information Network Clinical Trial Registry (UMIN000040487).

12.
Diabetes Obes Metab ; 21(8): 1990-1995, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30993861

RESUMO

A prospective, multicentre, open-label, blinded-endpoint, randomized controlled study was conducted to evaluate the efficacy of treatment with ipragliflozin (sodium-dependent glucose transporter-2 inhibitor) versus metformin for visceral fat reduction and glycaemic control among Japanese patients with type 2 diabetes treated with sitagliptin, HbA1c levels of 7%-10%, and body mass index (BMI) ≥ 22 kg/m2 . Patients were randomly assigned (1:1) to receive ipragliflozin 50 mg or metformin 1000-1500 mg daily. The primary outcome was change in visceral fat area as measured by computed tomography after 24 weeks of therapy. The secondary outcomes were effects on glucose metabolism and lipid metabolism. Mean percentage reduction in visceral fat area was significantly greater in the ipragliflozin group than in the metformin group (-12.06% vs. -3.65%, P = 0.040). Ipragliflozin also significantly reduced BMI, subcutaneous fat area, waist circumference, fasting insulin, and homeostatic model assessment (HOMA)-resistance, and increased HDL-cholesterol levels. Metformin significantly reduced HbA1c and LDL-cholesterol levels and increased HOMA-beta. There were no severe adverse events. The use of ipragliflozin or metformin in combination with dipeptidyl peptidase-4 inhibitors, widely used in Japan, may have beneficial effects in ameliorating multiple cardiovascular risk factors.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos/administração & dosagem , Hipoglicemiantes/administração & dosagem , Gordura Intra-Abdominal/efeitos dos fármacos , Metformina/administração & dosagem , Tiofenos/administração & dosagem , Adulto , Idoso , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Quimioterapia Combinada , Feminino , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Método Simples-Cego , Fosfato de Sitagliptina/administração & dosagem , Resultado do Tratamento
13.
J Am Soc Nephrol ; 29(12): 2795-2808, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30377232

RESUMO

BACKGROUND: The mammalian kidney develops through reciprocal inductive signals between the metanephric mesenchyme and ureteric bud. Transcription factor 21 (Tcf21) is highly expressed in the metanephric mesenchyme, including Six2-expressing cap mesenchyme and Foxd1-expressing stromal mesenchyme. Tcf21 knockout mice die in the perinatal period from severe renal hypodysplasia. In humans, Tcf21 mRNA levels are reduced in renal tissue from human fetuses with renal dysplasia. The molecular mechanisms underlying these renal defects are not yet known. METHODS: Using a variety of techniques to assess kidney development and gene expression, we compared the phenotypes of wild-type mice, mice with germline deletion of the Tcf21 gene, mice with stromal mesenchyme-specific Tcf21 deletion, and mice with cap mesenchyme-specific Tcf21 deletion. RESULTS: Germline deletion of Tcf21 leads to impaired ureteric bud branching and is accompanied by downregulated expression of Gdnf-Ret-Wnt11, a key pathway required for branching morphogenesis. Selective removal of Tcf21 from the renal stroma is also associated with attenuation of the Gdnf signaling axis and leads to a defect in ureteric bud branching, a paucity of collecting ducts, and a defect in urine concentration capacity. In contrast, deletion of Tcf21 from the cap mesenchyme leads to abnormal glomerulogenesis and massive proteinuria, but no downregulation of Gdnf-Ret-Wnt11 or obvious defect in branching. CONCLUSIONS: Our findings indicate that Tcf21 has distinct roles in the cap mesenchyme and stromal mesenchyme compartments during kidney development and suggest that Tcf21 regulates key molecular pathways required for branching morphogenesis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Rim/embriologia , Rim/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Regulação para Baixo , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Humanos , Imuno-Histoquímica , Rim/anormalidades , Mesoderma/embriologia , Mesoderma/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Morfogênese/genética , Gravidez , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
14.
Int J Oncol ; 52(2): 505-517, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29207179

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of primary effusion lymphoma (PEL) and Kaposi's sarcoma. PEL is a type of non-Hodgkin's B-cell lymphoma, affecting immunosuppressed individuals, such as post-transplant or AIDS patients. However, since PEL is resistant to chemotherapeutic regimens, new effective treatment strategies are required. Arctigenin, a natural lignan compound found in the plant Arctium lappa, has been widely investigated as a potential anticancer agent in the clinical setting. In the present study, we examined the cytotoxic effects of arctigenin by cell viability assay and found that arctigenin markedly inhibited the proliferation of PEL cells compared with KSHV-uninfected B-lymphoma cells under conditions of glucose deprivation. Arctigenin decreased cellular ATP levels, disrupted mitochondrial membrane potential and triggered caspase-9-mediated apoptosis in the glucose-deprived PEL cells. In addition, western blot analysis using phospho-specific antibodies were used to evaluate activity changes in the signaling pathways of interest. As a result, arctigenin suppressed the activation of the extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (p38 MAPK) signaling pathways by inhibiting ERK and p38 MAPK phosphorylation in the glucose-deprived PEL cells. We confirmed that an inhibitor of ERK (U0126) or p38 MAPK (SB202190 and SB203580) suppressed the proliferation of the BC3 PEL cells compared with the KSHV-negative DG75 cells. Moreover, RT-PCR and luciferase reporter assay revealed that arctigenin and p38 MAPK inhibition by SB202190 or SB203580 downregulated the transcriptional expression of unfolded protein response (UPR)­related molecules, including GRP78 and ATF6α under conditions of glucose deprivation. Finally, we confirmed that arctigenin did not affect KSHV replication in PEL cells, suggesting that arctigenin treatment for PEL does not contribute to the risk of de novo KSHV production. These data thus indicate that arctigenin may serve as a lead compound for the development of novel and effective drugs for the treatment of PEL.


Assuntos
Apoptose/efeitos dos fármacos , Furanos/farmacologia , Lignanas/farmacologia , Linfoma de Efusão Primária/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Glucose/deficiência , Infecções por Herpesviridae/complicações , Herpesvirus Humano 8/efeitos dos fármacos , Humanos , Linfoma de Efusão Primária/virologia
15.
J Diabetes Investig ; 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28895299

RESUMO

Lipodystrophy is a rare condition that is often accompanied by one or more metabolic diseases. Here, we report a case of lipoatrophic diabetes induced by juvenile dermatomyositis. Although pioglitazone was not effective for lowering blood glucose levels, our observation suggested that it improved liver function slightly. The effectiveness of metreleptin for lowering blood glucose levels could not be determined, as we administered it in a short period. Liver biopsy showed burned-out non-alcoholic steatohepatitis. The present results show that the successful treatment of lipoatrophic diabetes induced by juvenile dermatomyositis requires an early diagnosis and therapeutic intervention.

17.
Chem Biol Interact ; 266: 28-37, 2017 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-28161410

RESUMO

Selenium compounds such as methylseleninic acid (MSA) and sodium selenite (SS) have been widely evaluated as potential anti-cancer agents in the clinical setting. Primary effusion lymphoma (PEL) is a non-Hodgkin's B-cell lymphoma, associated with immunosuppressed individuals, such as post-transplant or AIDS patients. Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of PEL and Kaposi's sarcoma. Here, we found that MSA and SS markedly inhibited the growth of PEL cells compared with KSHV-uninfected B cells. MSA and SS caused ER stress, inducing the unfolded protein response (UPR) pathway in PEL cells that resulted in pro-apoptotic UPR, and finally apoptosis. The expression of UPR-related molecules (GRP78 and GADD34) and pro-apoptotic UPR molecules (CHOP, Bim, or Puma) were augmented in PEL cells treated with MSA or SS. In addition, these compounds induced the activation of caspase-4, an ER stress specific caspase, as well as caspase-3,-7, and -9 in PEL cells. We confirmed that thapsigargin which is an inducer of ER stress, dramatically decreased the viability of PEL cells, compared with KSHV-uninfected Ramos cells. We also investigated whether MSA or SS caused oxidization of cellular proteins in PEL cells. MSA and SS increased the levels of oxidative proteins in PEL cells, and the anti-oxidant agent (N-acetyl-l-cysteine) restored cell viability and suppressed caspase-7 activation in PEL cells treated with MSA or SS. Finally, we confirmed that MSA and SS induced neither lytic replication nor viral production in PEL cells. Taken together, MSA and SS could serve as lead compounds for the development of novel and effective drugs against PEL without the risk of de novo KSHV production.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Selenito de Sódio/farmacologia , Resposta a Proteínas não Dobradas , Apoptose/genética , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Humanos , Estresse Oxidativo/efeitos dos fármacos
18.
Biochem Biophys Res Commun ; 469(3): 565-72, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26692493

RESUMO

Primary effusion lymphoma (PEL), a subtype of non-Hodgkin's B-lymphoma, is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV) in immunosuppressed patients. Endoplasmic reticulum (ER) stress induces activation of the unfolded protein response (UPR), which induces expression of ER chaperones, which in turn decrease ER stress, leading to ER homeostasis. The UPR is necessary for not only ER homeostasis but also persistent infection by, and replication of, many viruses. However, the precise roles and regulation of the UPR in KSHV infection remain poorly understood. Here, we found that IRE1α and PERK were significantly downregulated in PEL cells cultured under normal conditions, compared with KSHV-uninfected B-lymphoma cells. IRE1α and PERK mRNA levels were decreased in PEL cells, and KSHV-encoded LANA and v-cyclin D led to suppressed IRE1α transcription. Thapsigargin-induced ER stress activated the UPR and increased the mRNA levels of UPR-related molecules, including IRE1α and PERK, in PEL cells. However the IRE1α and PERK mRNA levels in PEL cells were lower than those in KSHV-uninfected cells. Furthermore, ER stress induced by brefeldin A and thapsigargin dramatically reduced the viability of PEL cells, compared with KSHV-uninfected cells, and induced apoptosis of PEL cells via the pro-apoptotic UPR through expression of CHOP and activation of caspase-9. In addition to the pro-apoptotic UPR, thapsigargin-induced ER stress enhanced transcription of lytic genes, including RTA, K-bZIP and K8.1, and viral production in PEL cells resulted in induction of the lytic cycle. Thus, we demonstrated downregulation of IRE1α and PERK in PEL cells, transcriptional suppression of IRE1α by LANA and v-cyclin D, apoptosis induction in PEL cells by ER stress, and potentiation of lytic replication by ER stress.


Assuntos
Estresse do Retículo Endoplasmático , Herpesvirus Humano 8/fisiologia , Linfoma de Efusão Primária/fisiopatologia , Linfoma de Efusão Primária/virologia , Resposta a Proteínas não Dobradas , Replicação Viral/fisiologia , Sobrevivência Celular , Células HeLa , Humanos , Linfoma de Efusão Primária/patologia
19.
Angew Chem Int Ed Engl ; 53(42): 11228-31, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25082189

RESUMO

In a mixed-valence polyoxometalate, electrons are usually delocalized within the cluster anion because of low level of inter-cluster interaction. Herein, we report the structure and electrical properties of a single crystal in which mixed-valence polyoxometalates were electrically wired by cationic π-molecules of tetrathiafulvalene substituted with pyridinium. Electron-transport characteristics are suggested to represent electron hopping through strong interactions between cluster and cationic π-molecules.

20.
J Am Chem Soc ; 133(12): 4224-7, 2011 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-21370861

RESUMO

Niobic acid, Nb(2)O(5)·nH(2)O, has been studied as a heterogeneous Lewis acid catalyst. NbO(4) tetrahedra, Lewis acid sites, on Nb(2)O(5)·nH(2)O surface immediately form NbO(4)-H(2)O adducts in the presence of water. However, a part of the adducts can still function as effective Lewis acid sites, catalyzing the allylation of benzaldehyde with tetraallyl tin and the conversion of glucose into 5-(hydroxymethyl)furfural in water.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA