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1.
Int J Biol Macromol ; 241: 124559, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37100312

RESUMO

A sulfated galactoglucan (3-SS) was discovered in Antrodia cinnamomea with antiproliferative and anti-inflammatory activities. Chemical identification of 3-SS resulted in the determination of a partial repeat unit as a 2-O sulfated 1,3-/1,4-linked galactoglucan with a two-residual 1,6-O-ß-Glc branch on the 3-O position of a Glc. by monosaccharide analysis and 1D and 2D NMR spectroscopy. The anti-inflammation effects of 3-SS on RAW264.7 macrophage cells, such as IL-6 inhibition, restoration of LPS-induced IκB protein degradation, and inhibited LPS-induced TGFRII protein degradation, were confirmed to occur via AKT, ERK1/2, and p-38. In addition, 3-SS impaired the proliferation of H1975 lung cancer cells through EGFR/ERK/slug signaling. This is the first finding of 2-O sulfated 1,3-/1,4-galactoglucan with 1,6-ß-Glc branches with dual functions of anti-inflammatory and antiproliferative activities.


Assuntos
Antrodia , Sulfatos , Sulfatos/química , Lipopolissacarídeos , Anti-Inflamatórios/farmacologia , Antrodia/química
2.
Front Chem ; 10: 931584, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35880111

RESUMO

The blood-brain barrier (BBB) is a highly selective cellular barrier that tightly controls the microenvironment of the central nervous system to restrict the passage of substances, which is a primary challenge in delivering therapeutic drugs to treat brain diseases. This study aimed to develop simple surface modifications of mesoporous silica nanoparticles (MSNs) without external stimuli or receptor protein conjugation, which exhibited a critical surface charge and size allowing them to cross the BBB. A series of MSNs with various charges and two different sizes of 50 and 200 nm were synthesized, which showed a uniform mesoporous structure with various surface zeta potentials ranging from +42.3 to -51.6 mV. Confocal microscopic results showed that 50 nm of strongly negatively charged N4-RMSN50@PEG/THPMP (∼-40 mV) could be significantly observed outside blood vessels of the brain in Tg(zfli1:EGFP) transgenic zebrafish embryos superior to the other negatively charged MSNs. However, very few positively charged MSNs were found in the brain, indicating that negatively charged MSNs could successfully penetrate the BBB. The data were confirmed by high-resolution images of 3D deconvoluted confocal microscopy and two-photon microscopy and zebrafish brain tissue sections. In addition, while increasing the size to 200 nm but maintaining the similar negative charge (∼40 mV), MSNs could not be detected in the brain of zebrafish, suggesting that transport across the BBB based on MSNs occurred in charge- and size-dependent manners. No obvious cytotoxicity was observed in the CTX-TNA2 astrocyte cell line and U87-MG glioma cell line treated with MSNs. After doxorubicin (Dox) loading, N4-RMSN50@PEG/THPMP/Dox enabled drug delivery and pH-responsive release. The toxicity assay showed that N4-RMSN50@PEG/THPMP could reduce Dox release, resulting in the increase of the survival rate in zebrafish. Flow cytometry demonstrated N4-RMSN50@PEG/THPMP had few cellular uptakes. Protein corona analysis revealed three transporter proteins, such as afamin, apolipoprotein E, and basigin, could contribute to BBB penetration, validating the possible mechanism of N4-RMSN50@PEG/THPMP crossing the BBB. With this simple approach, MSNs with critical negative charge and size could overcome the BBB-limiting characteristics of therapeutic drug molecules; furthermore, their use may also cause drug sustained-release in the brain, decreasing peripheral toxicity.

3.
Molecules ; 25(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979200

RESUMO

Compound 1 is a curcumin di-O-2,2-bis(hydroxymethyl)propionate that shows significant in vitro and in vivo inhibitory activity against MDA-MB-231 cells with eight to ten-fold higher potency than curcumin. Here, we modified the α-position (C-4 position) of the central 1,3-diketone moiety of 1 with polar or nonpolar functional groups to afford a series of 4,4-disubstituted curcuminoid 2,2-bis(hydroxymethyl)propionate derivatives and evaluated their anticancer activities. A clear structure-activity relationship of compound 1 derivatives focusing on the functional groups at the C-4 position was established based on their anti-proliferative effects against the MDA-MB-231 and HCT-116 cell lines. Compounds 2-6 are 4,4-dimethylated, 4,4-diethylated, 4,4-dibenzylated, 4,4-dipropargylated and 4,4-diallylated compound 1, respectively. Compounds 2m-6m, the ester hydrolysis products of compounds 2-6, respectively, were synthesized and assessed for anticancer activity. Among all compound 1 derivatives, compound 2 emerged as a potential chemotherapeutic agent for colon cancer due to the promising in vivo anti-proliferative activities of 2 (IC50 = 3.10 ± 0.29 µM) and its ester hydrolysis product 2m (IC50 = 2.17 ± 0.16 µM) against HCT-116. The preliminary pharmacokinetic evaluation of 2 implied that 2 and 2m are main contributors to the in vivo efficacy. Compound 2 was further evaluated in an animal study using HCT-116 colon tumor xenograft bearing nude mice. The results revealed a dose-dependent efficacy that led to tumor volume reductions of 27%, 45%, and 60% at 50, 100, and 150 mg/kg doses, respectively. The established structure-activity relationship and pharmacokinetic outcomes of 2 is the guidance for future development of 4,4-disubstituted curcuminoid 2,2-bis(hydroxymethyl)- propionate derivatives as anticancer drug candidates.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Curcumina/química , Células HCT116 , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Camundongos , Camundongos Nus , Ratos Sprague-Dawley , Relação Estrutura-Atividade
4.
Clin Endocrinol (Oxf) ; 80(4): 508-15, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24102421

RESUMO

OBJECTIVE: Secondary hyperparathyroidism and its associated abnormalities in mineral metabolism and haemodynamic changes increase the cardiovascular risk in patients with end-stage renal disease (ESRD). Our objective was to determine the association of parathyroidectomy (PTX) with major cardiovascular events in nondiabetic dialysis patients with severe secondary hyperparathyroidism (SHPTH). DESIGN AND PATIENTS: We performed a cohort study with fifty-three nondiabetic ESRD patients who were treated with maintenance haemodialysis and who had intact parathyroid hormone (PTH) levels > 800 pg/ml. Participants received either only medical therapy or medical therapy and total PTX with autotransplantation for SHPTH. MEASUREMENTS: We evaluated the associations between PTX and major cardiovascular events including death, cerebrovascular accident and myocardial infarction. The biochemical and haemodynamic changes associated with PTX were measured. RESULTS: During the mean follow-up of 72 months, twenty-three patients received only medical treatment (medical group) while thirty patients underwent PTX in addition to medical treatment (PTX group). The two groups were comparable in respect of baseline characteristics. PTX group was found to be associated with a reduced incidence of major cardiovascular events (P = 0·021). A multiple Cox regression analysis showed that the variable significantly associated with major cardiovascular events was treatment modality (medical therapy vs medical therapy and parathyroidectomy, hazard ratio = 26·12, 95% CI = 1·30-526·27, P = 0·033). Blood pressure, haemoglobin, alkaline phosphatase, calcium, phosphate and calcium × phosphate product significantly improved after PTX. CONCLUSIONS: PTX was associated with better cardiovascular outcome in nondiabetic dialysis patients with severe SHPTH.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Hiperparatireoidismo Secundário/cirurgia , Falência Renal Crônica/terapia , Paratireoidectomia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal , Fatores de Risco
5.
Blood Purif ; 32(3): 232-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21829015

RESUMO

BACKGROUND: The objective of this study was to assess the impact of heparin concentration retained in temporary double-lumen catheters on bleeding risk. METHODS: Activated partial thromboplastin time (aPTT) was measured in patients hemodialyzed via double-lumen catheters. Heparin solutions of 5,000 U/ml (group 1, n = 95) and 1,000 U/ml (group 2, n = 89) were randomly retained in catheters after placement and each hemodialysis (HD) session. Blood transfusion, bleeding episodes, and changes of hematocrit were recorded. RESULTS: The aPTT at the beginning of HD or 10 min after heparin lock was significantly prolonged, which was more prominent in the 5,000 U/ml group, whereas the aPTT declined to baseline values at the end of HD or before the next dialysis session in both groups. Infection and occlusion rates were similar in both groups. More patients suffered from major bleeding and prominent decline of hematocrit in the 5,000 U/ml group. CONCLUSIONS: Low-dose heparin (1,000 U/ml) retention in double-lumen catheters for temporary HD maintains comparable catheter patency and might reduce the bleeding risk.


Assuntos
Anticoagulantes/farmacologia , Catéteres , Hemorragia/prevenção & controle , Heparina/farmacologia , Diálise Renal , Idoso , Cateterismo , Hematócrito , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Fatores de Risco
6.
Exp Cell Res ; 316(7): 1109-18, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20202468

RESUMO

PURPOSE: Tumor growth factor-beta1 (TGF-beta1) plays a pivotal role in processes like kidney epithelial-mesenchymal transition (EMT) and interstitial fibrosis, which correlate well with progression of renal disease. Little is known about underlying mechanisms that regulate EMT. Based on the anatomical relationship between erythropoietin (EPO)-producing interstitial fibroblasts and adjacent tubular cells, we investigated the role of EPO in TGF-beta1-mediated EMT and fibrosis in kidney injury. METHODS: We examined apoptosis and EMT in TGF-beta1-treated LLC-PK1 cells in the presence or absence of EPO. We examined the effect of EPO on TGF-beta1-mediated Smad signaling. Apoptosis and cell proliferation were assessed with flow cytometry and hemocytometry. We used Western blotting and indirect immunofluorescence to evaluate expression levels of TGF-beta1 signal pathway proteins and EMT markers. RESULTS: We demonstrated that ZVAD-FMK (a caspase inhibitor) inhibited TGF-beta1-induced apoptosis but did not inhibit EMT. In contrast, EPO reversed TGF-beta1-mediated apoptosis and also partially inhibited TGF-beta1-mediated EMT. We showed that EPO treatment suppressed TGF-beta1-mediated signaling by inhibiting the phosphorylation and nuclear translocation of Smad 3. Inhibition of mitogen-activated protein kinase kinase 1 (MEK 1) either directly with PD98059 or with MEK 1 siRNA resulted in inhibition of EPO-mediated suppression of EMT and Smad signal transduction in TGF-beta1-treated cells. CONCLUSIONS: EPO inhibited apoptosis and EMT in TGF-beta1-treated LLC-PK1 cells. This effect of EPO was partially mediated by a mitogen-activated protein kinase-dependent inhibition of Smad signal transduction.


Assuntos
Epitélio/efeitos dos fármacos , Eritropoetina/farmacologia , Rim/efeitos dos fármacos , Mesoderma/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Proteínas Smad/antagonistas & inibidores , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Inibidores de Caspase , Caspases/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Regulação para Baixo/efeitos dos fármacos , Epitélio/fisiologia , Rim/metabolismo , Rim/fisiologia , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/fisiologia , Mesoderma/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Proteínas Smad/fisiologia , Suínos , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Fator de Crescimento Transformador beta1/farmacologia
7.
Food Chem Toxicol ; 46(5): 1744-52, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18294746

RESUMO

We have previously discovered that star fruit can induce oliguric acute renal failure. To investigate the mechanisms of star fruit-associated acute oxalate nephropathy, the nephrotoxic effect of star fruit was examined in both cellular experiments and animal models. We evaluated renal function, pathological changes in kidney tissues and apoptotic effects using terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) assay in four groups of rats -- a control group (CG), fed with tap water (1); a star fruit group (SG), fed with star fruit juice naturally containing 0.2M oxalate (2); and oxalate groups (OxG), fed with 0.2M (3) or 0.4M (4) oxalate solution. The effects of both star fruit juice and oxalate on MDCK cells were also analyzed by flow cytometry. We found that the mean creatinine clearance was significantly lower in the SG, 0.2M OxG and 0.4M OxG. Dose-dependent apoptotic effects were evident from the TUNEL assay, and flow cytometry analysis of treated MDCK cells showed dose- and time-dependent effects. Our findings suggest that star fruit juice produces acute renal injury, not only through the obstructive effect of calcium oxalate crystals, but also by inducing apoptosis of renal epithelial cells, which may be caused by the levels of oxalate in the fruit.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/patologia , Frutas/toxicidade , Animais , Células Cultivadas , Creatinina/sangue , Creatinina/urina , Relação Dose-Resposta a Droga , Enzimas/urina , Citometria de Fluxo , Frutas/química , Marcação In Situ das Extremidades Cortadas , Rim/patologia , Testes de Função Renal , Masculino , Oxalatos/sangue , Oxalatos/urina , Ratos , Ratos Sprague-Dawley
8.
J Formos Med Assoc ; 101(6): 421-4, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12189648

RESUMO

Hashimoto's thyroiditis is associated with myeloproliferative and lymphoproliferative neoplasms. The risk of carcinoma of the thyroid gland is increased in these patients. Furthermore, multiple myeloma can present together with some autoimmune diseases. We report the case of a 57-year-old woman with Hashimoto's thyroiditis who developed multiple myeloma with myeloma nephropathy. Her renal function deteriorated to end stage and she required maintenance hemodialysis. Although autoimmune disorder might play an important role in lymphomagenesis in patients with Hashimoto's thyroiditis, it is not known whether the chronic inflammation that takes place in Hashimoto's thyroiditis stimulates the development of multiple myeloma. The pathogenetic mechanisms responsible for the development of multiple myeloma in patients with Hashimoto's thyroiditis remain unclear.


Assuntos
Injúria Renal Aguda/complicações , Mieloma Múltiplo/complicações , Tireoidite Autoimune/complicações , Injúria Renal Aguda/patologia , Medula Óssea/patologia , Feminino , Humanos , Rim/patologia , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia
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