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1.
Biochemistry ; 63(10): 1241-1245, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38724483

RESUMO

Natural products are important sources of seed compounds for drug discovery. However, it has become difficult in recent years to discover new compounds with valuable pharmacological activities. On the other hand, among the vast number of natural products that have been isolated so far, a considerable number of compounds with specific biological activities are thought to be overlooked in screening that uses biological activity as an index. Therefore, it is conceivable that such overlooked useful compounds may be found by screening compound libraries that have been amassed previously through specific assays. Previously, NPD723, a member of the Natural Products Depository library comprised of a mixture of natural and non-natural products developed at RIKEN, and its metabolite H-006 were found to inhibit growth of various cancer cells at low nanomolar half-maximal inhibitory concentration. Subsequent analysis revealed that H-006 strongly inhibited human dihydroorotate dehydrogenase (DHODH), the rate-limiting enzyme in the de novo pyrimidine biosynthetic pathway. Here, we elucidated the crystal structure of the DHODH-flavin mononucleotide-orotic acid-H-006 complex at 1.7 Å resolution to determine that furocoumavirin, the S-enantiomer of H-006, was the actual inhibitor. The overall mode of interaction of furocoumavirin with the inhibitor binding pocket was similar to that described for previously reported tight-binding inhibitors. However, the structural information together with kinetic characterizations of site-specific mutants identified key unique features that are considered to contribute to the sub-nanomolar inhibition of DHODH by furocoumavirin. Our finding identified new chemical features that could improve the design of human DHODH inhibitors.


Assuntos
Antivirais , Di-Hidro-Orotato Desidrogenase , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Humanos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/química , Antivirais/farmacologia , Antivirais/química , Cristalografia por Raios X , Furocumarinas/farmacologia , Furocumarinas/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Modelos Moleculares
2.
Exp Biol Med (Maywood) ; 248(13): 1112-1123, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37646078

RESUMO

Non-alcoholic steatohepatitis (NASH) is a progressive form of non-alcoholic fatty liver disease (NAFLD) that causes cirrhosis and hepatocellular carcinoma. Iron is an essential trace element in the body; however, excess iron can cause tissue damage and dysfunction. Iron overload is often observed in patients with NASH, and the amount of iron accumulated in the liver positively correlates with the histological severity of NASH. Ferroptosis, a novel form of iron-dependent cell death, is caused by the accumulation of lipid peroxidation and oxidative stress and is related to NASH. In addition, ferroptosis is closely related to autophagy, an intracellular self-degradation process. Although autophagy has many beneficial effects, it may also be harmful to the organism, for example, inducing ferroptosis. It is unclear whether iron overload aggravates NASH via autophagy. The aim of this research is to determine the mechanism by which iron overload induces ferroptosis via autophagy and aggravates NASH. Stroke-prone spontaneously hypertensive rats (SHRSP5/Dmcr) were divided into two groups and fed a high-fat and high-cholesterol (HFC) diet for eight weeks. Iron dextran was administered to the Fe group in addition to the HFC diet. Blood analysis, histological staining, calcineurin activity assay, quantitative reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence staining, and electron microscopy were performed. The results showed that iron overload promoted autophagy via nuclear translocation of transcription factor EB (TFEB) and induced ferritinophagy, which is the autophagic degradation of ferritin. In addition, the HFC diet induced lipophagy, the autophagic degradation of lipid droplets. The Fe group also exhibited promoted ferroptosis and aggravated hepatic inflammation and fibrosis. In conclusion, iron overload accelerates ferritinophagy and lipophagy, aggravating NASH pathology via ferroptosis. These findings indicate the therapeutic potential of inhibiting autophagy and ferroptosis for treating NASH.


Assuntos
Ferroptose , Sobrecarga de Ferro , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos Endogâmicos SHR , Sobrecarga de Ferro/complicações , Fibrose , Ferro , Autofagia , Neoplasias Hepáticas/complicações
3.
J Appl Biomed ; 21(2): 80-90, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37376883

RESUMO

BACKGROUND: Xanthine oxidase (XO) generates reactive oxygen species during uric acid production. Therefore, XO inhibitors, which suppress oxidative stress, may effectively treat non-alcoholic steatohepatitis (NASH) and atherosclerosis via uric acid reduction. In this study, we examined the antioxidant effect of the XO inhibitor febuxostat on NASH and atherosclerosis in stroke-prone spontaneously hypertensive 5 (SHRSP5/Dmcr) rats. METHODS: SHRSP5/Dmcr rats were divided into three groups: SHRSP5/Dmcr + high-fat and high-cholesterol (HFC) diet [control group, n = 5], SHRSP5/Dmcr + HFC diet + 10% fructose (40 ml/day) [fructose group, n = 5], and SHRSP5/Dmcr + HFC diet + 10% fructose (40 ml/day) + febuxostat (1.0 mg/kg/day) [febuxostat group, n = 5]. Glucose and insulin resistance, blood biochemistry, histopathological staining, endothelial function, and oxidative stress markers were evaluated. RESULTS: Febuxostat reduced the plasma uric acid levels. Oxidative stress-related genes were downregulated, whereas antioxidant factor-related genes were upregulated in the febuxostat group compared with those in the fructose group. Febuxostat also ameliorated inflammation, fibrosis, and lipid accumulation in the liver. Mesenteric lipid deposition decreased in the arteries, and aortic endothelial function improved in the febuxostat group. CONCLUSIONS: Overall, the XO inhibitor febuxostat exerted protective effects against NASH and atherosclerosis in SHRSP5/Dmcr rats.


Assuntos
Aterosclerose , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Febuxostat/farmacologia , Febuxostat/uso terapêutico , Xantina Oxidase , Ácido Úrico , Ratos Endogâmicos SHR , Dieta Hiperlipídica , Inibidores Enzimáticos , Aterosclerose/tratamento farmacológico , Lipídeos
4.
Can J Physiol Pharmacol ; 101(9): 455-465, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224568

RESUMO

The liver X receptor (LXR) can enhance cholesterol transporters, which could remove excess cholesterol from foam cells in atheromas. LXR has two subtypes: LXRα, which aggravates hepatic lipid accumulation, and LXRß, which does not. In 2018, ouabagenin (OBG) was reported as a potential LXRß-specific agonist. We aimed to examine whether OBG specifically affects LXRß in nonalcoholic steatohepatitis (NASH); it did not aggravate hepatic steatosis and can suppress the development of atherosclerosis. SHRSP5/Dmcr rats fed a high-fat and high-cholesterol diet were divided into four groups as follows: (I) L-NAME group, (II) L-NAME/OBG group, (III) OBG (-) group, and (IV) OBG (+) group. All groups' rats were intraperitoneally administered L-NAME. The L-NAME/OBG group's rats were intraperitoneally administered OBG and L-NAME simultaneously. After L-NAME administration, the OBG (+) group's rats were administered OBG, while the OBG (-) group's rats were not. Although all rats developed NASH, OBG did not exacerbate steatosis (L-NAME/OBG and OBG (+) groups). In addition, endothelial cells were protected in the L-NAME/OBG group and foam cells in the atheroma were reduced in the OBG (+) group. OBG is an LXRß-specific agonist and has a potential therapeutic effect on atherosclerosis without developing lipid accumulation in the liver.


Assuntos
Aterosclerose , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Receptores X do Fígado , NG-Nitroarginina Metil Éster , Células Endoteliais , Ratos Endogâmicos SHR , Dieta Hiperlipídica/efeitos adversos , Fígado , Aterosclerose/tratamento farmacológico , Colesterol
5.
Ann Anat ; 249: 152104, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37209870

RESUMO

BACKGROUND: Secondary sarcopenia develops as a result of a bedridden state and illnesses, such as cachexia, liver disease, and diabetes. However, there is a lack of animal models to investigate the underlying mechanisms and potential treatments for secondary sarcopenia. Recently, secondary sarcopenia has been associated with the prognosis of nonalcoholic steatohepatitis. This study aimed to investigate whether stroke-prone spontaneously hypertensive rat 5 (SHRSP5/Dmcr) which developed severe nonalcoholic steatohepatitis by a high-fat and high-cholesterol (HFC; containing 2% cholic acid) diet is a useful model of secondary sarcopenia. METHODS: SHRSP5/Dmcr rats were divided into 6 groups fed with a Stroke-Prone (SP: normal chow) or HFC diets for different periods (4, 12, and 20 weeks), and WKY/Izm rats were divided into 2 groups fed an SP or HFC diet. Body weight, food intake, and muscle force were measured weekly for all rats. After the end of the diet period, skeletal muscle strength evoked by electrical stimulation was recorded, blood was collected, and organ weight was measured. The sera were used for biochemical analysis and the organs were used for histopathological analysis. RESULTS: SHRSP5/Dmcr rats fed an HFC diet developed nonalcoholic steatohepatitis, and their skeletal muscles, especially fast muscles, showed atrophy, indicating that muscle atrophy is aggravated by the progression of nonalcoholic steatohepatitis. In contrast, WKY/Izm rats fed an HFC diet did not exhibit sarcopenia. CONCLUSIONS: This study suggests that SHRSP5/Dmcr rats could be a useful novel model for investigate the mechanism of secondary sarcopenia disorder associated with nonalcoholic steatohepatitis.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Sarcopenia , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Sarcopenia/complicações , Sarcopenia/patologia , Ratos Endogâmicos WKY , Dieta Hiperlipídica/efeitos adversos , Ratos Endogâmicos SHR , Colesterol , Fígado/patologia , Modelos Animais de Doenças
6.
Acta Med Okayama ; 77(1): 29-36, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36849143

RESUMO

The SHRSP5/Dmcr is a useful animal model for the development of nonalcoholic steatohepatitis (NASH) pathology when fed a high-fat, high-cholesterol diet, and further drug interventions can lead to concomitant cardiovascular disease. While SHRSP5/Dmcr rats have been used for basic research related to NASH, details of their bile acid metabolism in this condition are unknown. In this study, we aimed to clarify the changes in the serum bile acid (BA) fractions associated with NASH and found that glycine-conjugated and unconjugated bile acid increased with worsening NASH and cardiovascular disease while taurine-conjugated BA relatively decreased.


Assuntos
Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Animais , Ratos , Doenças Cardiovasculares/etiologia , Ácidos e Sais Biliares , Glicina , Taurina
7.
J Am Chem Soc ; 145(5): 3221-3228, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36706030

RESUMO

Pathogenic fungi of Aspergillus section Fumigati are known to produce various secondary metabolites. A reported isolation of a compound with an atypical carbon skeleton called fumimycin from A. fumisynnematus prompted us to examine a related fungus, A. lentulus, for production of similar products. Here we report the isolation of fumimycin and a related new racemic compound we named lentofuranine. Detailed analyses revealed that both compounds were assembled by a nonenzymatic condensation of a polyketide intermediate from the terrein biosynthetic pathway and a highly reactive azlactone intermediate produced by an unrelated nonribosomal peptide synthetase carrying a terminal condensation-like domain. While highly reactive azlactone is commonly used in chemical synthesis, its production by a conventional non-metalloenzyme and employment as a biosynthetic pathway intermediate is unprecedented. The observed unusual carbon skeleton formation is likely due to the reactivity of azlactone. Our finding provides another example of a chemical principle being aptly exploited by a biological system.


Assuntos
Aspergillus , Carbono , Aspergillus/metabolismo , Carbono/metabolismo
8.
Chem Res Toxicol ; 35(9): 1625-1630, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-36001821

RESUMO

Several aromatic amine compounds are urinary bladder carcinogens. Activated metabolites and DNA adducts of polycyclic aromatic amines, such as 4-aminobiphenyl, have been identified, whereas those of monocyclic aromatic amines, such as o-toluidine (o-Tol), o-anisidine (o-Ans), and aniline (Ani), have not been completely determined. We have recently reported that o-Tol and o-Ans are metabolically converted in vitro and in vivo to cytotoxic and mutagenic p-semidine-type dimers, namely 2-methyl-N4-(2-methylphenyl) benzene-1,4-diamine (MMBD) and 2-methoxy-N4-(2-methoxyphenyl) benzene-1,4-diamine (MxMxBD), respectively, suggesting their roles in urinary bladder carcinogenesis. In this study, we found that when o-Tol and o-Ans were incubated with S9 mix, MMBD and MxMxBD as well as two isomeric heterodimers, MMxBD and MxMBD, were formed. Therefore, any two of o-Tol, o-Ans, and Ani (10 mM each) were incubated with the S9 mix for up to 24 h and then subjected to LC-MS to investigate their metabolic kinetics. Metabolic conversions to all nine kinds of p-semidine-type homo- and hetero-dimers were observed, peaking at 6 h of incubation with the S9 mix; MxMxBD reached the peak at 6.1 ± 1.4 µM. Homo- and hetero-dimers containing the o-Ans moiety in the diamine structure showed a faster dimerization ratio, whereas levels of these dimers, such as MxMxBD, markedly declined with further incubation. Dimers containing o-Tol and Ani were relatively stable, even after incubation for 24 h. The electron-donating group of the o-Ans moiety may be involved in rapid metabolic conversion. In the cytotoxic assay, dimers with an o-Ans moiety in the diamine structure and MMBD showed approximately two- to four-fold higher cytotoxicity than other dimers in human bladder cancer T24 cells. These chemical and biological properties of homo- and hetero-dimers of monocyclic aromatic amines may be important when considering the combined exposure risk for bladder carcinogenesis.


Assuntos
Benzeno , Adutos de DNA , Aminas , Compostos de Anilina/metabolismo , Carcinogênese , Carcinógenos/toxicidade , Humanos , Fenilenodiaminas , Toluidinas
9.
Pharmacol Rep ; 74(4): 669-683, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35819592

RESUMO

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a progressive subtype of non-alcoholic fatty liver disease (NAFLD) that is closely related to cardiovascular disease (CVD). Nitric oxide (NO) plays a critical role in the control of various biological processes. Dysfunction of the NO signaling pathway is associated with various diseases such as atherosclerosis, vascular inflammatory disease, and diabetes. Recently, it has been reported that NO is related to lipid and cholesterol metabolism. Chronic NO synthase (NOS) inhibition accelerates NAFLD by increasing hepatic lipid deposition. However, the detailed relationship between NO and abnormal lipid and cholesterol metabolism in NAFLD/NASH has not been completely explained. We aimed to determine the effects of NOS inhibition by N omega-nitro-L-arginine methyl ester hydrochloride (L-NAME), a NOS inhibitor, on NASH and CVD via lipid and cholesterol metabolism. METHODS: Stroke-prone spontaneously hypertensive rats were fed a high-fat and high-cholesterol diet for 8 weeks and administered L-NAME for the last 2 weeks. Following blood and tissue sampling, biochemical analysis, histopathological staining, quantitative RT-PCR analysis, and western blotting were performed. RESULTS: L-NAME markedly increased hepatic triglyceride (TG) and cholesterol levels by promoting TG synthesis and cholesterol absorption from the diet. L-NAME increased the mRNA levels of inflammatory markers and fibrotic areas in the liver. Cholesterol secretion from the liver was promoted in rats administered L-NAME, which increased serum cholesterol. L-NAME significantly increased the level of oxidative stress marker and lipid deposition in the arteries. CONCLUSIONS: NOS inhibition simultaneously aggravates NASH and atherosclerosis via hepatic lipid and cholesterol metabolism.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Aceleração , Animais , Aterosclerose/metabolismo , Biomarcadores , Doenças Cardiovasculares/complicações , Colesterol , Dieta Hiperlipídica , Metabolismo dos Lipídeos , Fígado , NG-Nitroarginina Metil Éster/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Hepatopatia Gordurosa não Alcoólica/complicações , Ratos , Ratos Endogâmicos SHR
10.
Int J Mol Sci ; 23(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35269821

RESUMO

Osteoarthritis is a progressive disease characterized by cartilage destruction in the joints. Matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs) play key roles in osteoarthritis progression. In this study, we screened a chemical compound library to identify new drug candidates that target MMP and ADAMTS using a cytokine-stimulated OUMS-27 chondrosarcoma cells. By screening PCR-based mRNA expression, we selected 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide as a potential candidate. We found that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated IL-1ß-induced MMP13 mRNA expression in a dose-dependent manner, without causing serious cytotoxicity. Signaling pathway analysis revealed that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated ERK- and p-38-phosphorylation as well as JNK phosphorylation. We then examined the additive effect of 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide in combination with low-dose betamethasone on IL-1ß-stimulated cells. Combined treatment with 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide and betamethasone significantly attenuated MMP13 and ADAMTS9 mRNA expression. In conclusion, we identified a potential compound of interest that may help attenuate matrix-degrading enzymes in the early osteoarthritis-affected joints.


Assuntos
Cartilagem Articular , Osteoartrite , Betametasona , Cartilagem Articular/metabolismo , Células Cultivadas , Condrócitos/metabolismo , Humanos , Interleucina-1beta/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Osteoartrite/metabolismo , RNA Mensageiro/metabolismo
11.
Biochimie ; 197: 49-58, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35085709

RESUMO

A high-fat/high-cholesterol (HFC) diet, but not a high-cholesterol (HC) diet, is known to induce elevated serum apolipoprotein E (apoE)-rich high-density lipoprotein (HDL) levels in animal models. However, the exact mechanisms by which the combination of dietary fat and cholesterol induces apoE-rich HDL production is not well understood. Here, we investigated the effects of dietary fat and cholesterol on serum lipoprotein profiles and hepatic mRNA expression that are associated with HDL production, cholesterol transport, and bile acid metabolism. Male Sprague-Dawley rats were fed HFC, HC, high-fat, or control diets and then evaluated. The HFC diet induced significant increases in hepatic free-cholesterol accumulation (1.4-fold, p < 0.01) and serum apoE-rich HDL cholesterol (8.7-fold, p < 0.001) levels compared with the HC diet. The apoE-rich HDL induced by the HFC diet was remarkably rich in free cholesterol. Liver gene-expression was mostly similar between the HC and HFC diet groups. However, there was a significant increase of ATP-binding cassette transporter A1 (ABCA1) levels in the HFC group compared to the HC group for both mRNA (1.9-fold, p < 0.001) and protein (6.6-fold, p < 0.01). These results suggest that an increase in apoE-rich HDL induced by dietary fat and cholesterol may be involved in cholesterol efflux from the liver through increased ABCA1-mediated free-cholesterol efflux.


Assuntos
Transportador 1 de Cassete de Ligação de ATP , Colesterol , Dieta Hiperlipídica , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Colesterol/efeitos adversos , Colesterol/metabolismo , HDL-Colesterol/metabolismo , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/metabolismo , Fígado/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
12.
J Electromyogr Kinesiol ; 62: 102627, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34999536

RESUMO

The mechanomyogram (MMG) is a signal measured by various vibration sensors for slight vibrations induced by muscle contraction, and it reflects the muscle force during electrically induced-contraction or until 60%-70% maximum voluntary contraction, so the MMG is considered an alternative and novel measurement tool for muscle strength. We simultaneously measured the MMG and muscle force in the gastrocnemius (GC), vastus intermedius (VI), and soleus (SOL) muscles of rats. The muscle force was measured by attaching a hook to the tendon using a load cell, and the MMG was measured using a charged-coupled device-type displacement sensor at the middle of the target muscle. The MMG-twitch waveform was very similar to that of the muscle force; however, the half relaxation time and relaxation time (10%), which are relaxation parameters, were prolonged compared to those of the muscle force. The MMG amplitude correlated with the muscle force. Since stimulation frequencies that are necessary to evoke tetanic progression have a significant correlation with the twitch parameter, there is a close relationship between twitch and tetanus in the MMG signal. Therefore, we suggest that the MMG, which is electrically induced and detected by a laser displacement sensor, may be an alternative tool for measuring muscle strength.


Assuntos
Contração Muscular , Músculo Esquelético , Animais , Contração Isométrica , Ratos , Vibração
14.
Ann Nucl Med ; 35(11): 1203-1213, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34347268

RESUMO

OBJECTIVE: Recently, generative adversarial networks began to be actively studied in the field of medical imaging. These models are used for augmenting the variation of images to improve the accuracy of computer-aided diagnosis. In this paper, we propose an alternative new image generative model based on transformer decoder blocks and verify the performance of our model in generating SPECT images that have characteristics of Parkinson's disease patients. METHODS: Firstly, we proposed a new model architecture that is based on a transformer decoder block and is extended to generate slice images. From few superior slices of 3D volume, our model generates the rest of the inferior slices sequentially. Our model was trained by using [123I]FP-CIT SPECT images of Parkinson's disease patients that originated from the Parkinson's Progression Marker Initiative database. Pixel values of SPECT images were normalized by the specific/nonspecific binding ratio (SNBR). After training the model, we generated [123I]FP-CIT SPECT images. The transformation of images of the healthy control case SPECT images into PD-like images was also performed. Generated images were visually inspected and evaluated using the mean absolute value and asymmetric index. RESULTS: Our model was successfully generated and transformed into PD-like SPECT images. The mean absolute SNBR was mostly less than 0.15 in absolute value. The variation of the obtained dataset images was confirmed by the analysis of the asymmetric index. CONCLUSIONS: These results showed the potential ability of our new generative approach for SPECT images that the generative model based on the transformer realized both generation and transformation by a single model.


Assuntos
Tropanos , Tomografia Computadorizada de Emissão de Fóton Único
15.
Biomed Pharmacother ; 139: 111633, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34243624

RESUMO

Idiopathic pulmonary fibrosis (IPF) is the most common and most deadly form of interstitial lung disease. Osteopontin (OPN), a matricellular protein with proinflammatory and profibrotic properties, plays a major role in several fibrotic diseases, including IPF; OPN is highly upregulated in patients' lung samples. In this study, we knocked down OPN in a bleomycin (BLM)-induced pulmonary fibrosis (PF) mouse model using small interfering RNA (siRNA) to determine whether the use of OPN siRNA is an effective therapeutic strategy for IPF. We found that fibrosing areas were significantly smaller in specimens from OPN siRNA-treated mice. The number of alveolar macrophages, neutrophils, and lymphocytes in bronchoalveolar lavage fluid was also reduced in OPN siRNA-treated mice. Regarding the expression of epithelial-mesenchymal transition (EMT)-related proteins, the administration of OPN-siRNA to BLM-treated mice upregulated E-cadherin expression and downregulated vimentin expression. Moreover, in vitro, we incubated the human alveolar adenocarcinoma cell line A549 with transforming growth factor (TGF)-ß1 and subsequently transfected the cells with OPN siRNA. We found a significant upregulation of Col1A1, fibronectin, and vimentin after TGF-ß1 stimulation in A549 cells. In contrast, a downregulation of Col1A1, fibronectin, and vimentin mRNA levels was observed in TGF-ß1-stimulated OPN knockdown A549 cells. Therefore, the downregulation of OPN effectively reduced pulmonary fibrotic and EMT changes both in vitro and in vivo. Altogether, our results indicate that OPN siRNA exerts a protective effect on BLM-induced PF in mice. Our results provide a basis for the development of novel targeted therapeutic strategies for IPF.


Assuntos
Bleomicina/farmacologia , Transição Epitelial-Mesenquimal/genética , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Osteopontina/genética , Células A549 , Animais , Líquido da Lavagem Broncoalveolar , Linhagem Celular Tumoral , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/genética , Regulação para Cima/genética
16.
J Org Chem ; 86(4): 3605-3614, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33538172

RESUMO

The total synthesis of (+)-cannogenol, an aglycon common to various biologically important cardiotonic glycosides, has been achieved. Synthesis of the versatile intermediate involves Mizoroki-Heck and intramolecular Diels-Alder reactions from the enantiomerically pure CD-ring segment, newly prepared in a multidecagram scale this time. Total synthesis by the site-selective transformations of the versatile intermediate demonstrated the applicability of our synthetic approach.


Assuntos
Glicosídeos Cardíacos , Reação de Cicloadição , Estereoisomerismo
17.
Medicine (Baltimore) ; 99(34): e21794, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846812

RESUMO

Patients with cardiovascular diseases frequently experience exertional dyspnea. However, the relationship between respiratory muscle strength including its fatigue and cardiovascular dysfunctions remains to be clarified.The maximal inspiratory pressure/maximal expiratory pressure (MIP/MEP) before and after cardiopulmonary exercise testing (CPX) in 44 patients with heart failure and ischemic heart disease were measured. Respiratory muscle fatigue was evaluated by calculating MIP (MIPpost/MIPpre) and MEP (MEPpost/MEPpre) changes.The mean MIPpre and MEPpre values were 67.5 ±â€Š29.0 and 61.6 ±â€Š23.8 cm H2O, respectively. After CPX, MIP decreased in 25 patients, and MEP decreased in 22 patients. We evaluated the correlation relationship between respiratory muscle function including respiratory muscle fatigue and exercise capacity evaluated by CPX such as peak VO2 and VE/VCO2 slope. Among MIP, MEP, change in MIP, and change in MEP, only the value of change in MIP had an association with the value of VE/VCO2 slope (R = -0.36, P = .017). In addition, multivariate analysis for determining factor of change in MIP revealed that the association between the change in MIP and eGFR was independent from other confounding parameters (beta, 0.40, P = .017). The patients were divided into 2 groups, with (MIP change < 0.9) and without respiratory muscle fatigue (MIP change > 0.9), and a significant difference in peak VO2 (14.2 ±â€Š3.4 [with fatigue] vs 17.4 ±â€Š4.7 [without fatigue] mL/kg/min; P = .020) was observed between the groups.Respiratory muscle fatigue demonstrated by the change of MIP before and after CPX significantly correlated with exercise capacity and renal function in patients with cardiovascular disease.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Fadiga Muscular , Isquemia Miocárdica/fisiopatologia , Músculos Respiratórios/fisiopatologia , Idoso , Exercício Físico/fisiologia , Teste de Esforço , Tolerância ao Exercício , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/fisiopatologia , Masculino , Pressões Respiratórias Máximas , Pessoa de Meia-Idade
18.
Clin Chim Acta ; 510: 531-536, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798512

RESUMO

BACKGROUND: High-density lipoprotein (HDL) containing apolipoprotein E (apoE-rich HDL) represents a small portion of plasma HDL. We recently established a method for measuring plasma apoE-rich HDL. This study aimed to investigate the relationship between metabolic syndrome (MetS) and apoE-rich HDL levels. METHODS: The apoE-rich HDL-cholesterol (HDL-C) levels and metabolic characteristics of 113 patients were analyzed. RESULTS: The MetS group (n = 58) had significantly lower apoE-rich HDL-C and a lower apoE-rich HDL-C/HDL-C ratio (apoE-HDL (%)) compared to the non-MetS group. The prevalence of MetS was increased when apoE-HDL (%) decreased. In simple regression analyses, apoE-HDL (%) was significantly inversely correlated with visceral fat area (rs = -0.370, P < 0.001) and plasma triglycerides (rs = -0.447, P < 0.001) and positively correlated with low-density lipoprotein (LDL) mean particle size (rs = 0.599, P < 0.001) and HDL mean particle size (rs = 0.512, P < 0.001). Stepwise multiple regression analysis revealed that LDL mean particle size, a component of the atherogenic lipoprotein profile, was an independent predictor of apoE-HDL (%) (adjusted R2 = 0.409). CONCLUSIONS: Plasma apoE-rich HDL levels might be a valuable indicator of MetS. These findings may help further understand HDL subfraction analysis in cardiometabolic diseases.


Assuntos
Síndrome Metabólica , Apolipoproteínas E , HDL-Colesterol , LDL-Colesterol , Humanos , Lipoproteínas HDL , Triglicerídeos
19.
Ann Nucl Med ; 34(7): 512-515, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32314148

RESUMO

OBJECTIVE: An artificial intelligence (AI)-based algorithm typically requires a considerable amount of training data; however, few training images are available for dementia with Lewy bodies and frontotemporal lobar degeneration. Therefore, this study aims to present the potential of cycle-consistent generative adversarial networks (CycleGAN) to obtain enough number of training images for AI-based computer-aided diagnosis (CAD) algorithms for diagnosing dementia. METHODS: We trained CycleGAN using 43 amyloid-negative and 45 positive images in slice-by-slice. RESULTS: The CycleGAN can be used to synthesize reasonable amyloid-positive images, and the continuity of slices was preserved. DISCUSSION: Our results show that CycleGAN has the potential to generate a sufficient number of training images for CAD of dementia.


Assuntos
Demência/diagnóstico por imagem , Diagnóstico por Computador , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Tomografia por Emissão de Pósitrons , Humanos
20.
Exp Mol Pathol ; 114: 104437, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32246926

RESUMO

BACKGROUND AND AIMS: Nonalcoholic steatohepatitis (NASH) is linked to an increased risk of cardiovascular disease, regardless of the risk factors in metabolic syndrome. However, the intermediary factors between NASH and cardiovascular disease are still unknown. A previous study revealed that serum and hepatic bile acid (BA) levels are increased in some NASH patients. We aimed to examine whether NASH and cardiovascular disease were aggravated by BA using an animal model. METHOD AND RESULTS: From 10 to 18 weeks of age, SHRSP5/Dmcr rats divided into 3 groups were fed 3 types of high-fat and high-cholesterol (HFC) diets which were changed in the cholic acid (CA) concentration (0%, 2%, or 4%). The nitro oxide synthase inhibition (L-NAME) was administered intraperitoneally from 16 to 18 weeks of age. The 4% CA groups showed the worst LV dysfunction and myocardial fibrosis, and demonstrated severe hepatic fibrosis and lipid depositions. In addition, a large amount of lipid accumulation was observed in the aortas of the 4% CA group, and NFκB and VCAM-1 gene expression levels were increased. These findings were not seen in the 0% CA group. CONCLUSION: In the SHRSP5/Dmcr rat model, NASH and cardiovascular disease were aggravated with increasing BAs concentrations in an HFC diet.


Assuntos
Ácidos e Sais Biliares/farmacologia , Doenças Cardiovasculares/metabolismo , Ácido Cólico/farmacologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Ácidos e Sais Biliares/efeitos adversos , Ácidos e Sais Biliares/metabolismo , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Ácido Cólico/efeitos adversos , Ácido Cólico/metabolismo , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/genética , NF-kappa B/genética , NG-Nitroarginina Metil Éster/farmacologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos , Molécula 1 de Adesão de Célula Vascular/genética
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