Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Front Endocrinol (Lausanne) ; 14: 1202917, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37484958

RESUMEN

Background: Distal symmetric polyneuropathy (DSPN) is the most common chronic complication of type 2 diabetes mellitus (T2DM). DSPN may lead to more serious complications, such as diabetic foot ulcer, amputation, and reduced life expectancy. Observational studies have suggested that vitamin D deficiency may be associated with the development of DSPN in T2DM. However, interventional studies have found that low-dose vitamin D supplementation does not significantly improve neuropathy in DSPN. This study aims to evaluate the efficacy and safety of intramuscular injection of high-dose vitamin D (HDVD) in T2DM with DSPN combined with vitamin D insufficiency. Methods and analysis: We will conduct a multicenter, randomized, double-blinded, and placebo-controlled trial in four large hospitals. All eligible participants will be randomly assigned to either the vitamin D2 supplement or placebo control group and injected intramuscularly monthly for 3 months. Additionally, anthropometric measurements and clinical data will be collected at baseline and 3 months. Adverse events will be collected at 1, 2, and 3 months. The primary outcome measure is the change in the mean Michigan Neuropathy Screening Instrument (MNSI) score at baseline and 3 months post-intervention. We will use the gold-standard liquid chromatography-tandem mass spectrometry method to distinguish between 25(OH)D2 and 25(OH)D3 levels. The MNSN score before the intervention will be used as a covariate to compare the changes between both groups before and after the intervention, and the analysis of covariance will be used to analyze the change in the MNSI score after HDVD supplementation. Discussion: Glycemic control alone does not prevent the progression of DSPN in T2DM. Some studies have suggested that vitamin D may improve DSPN; however, the exact dose, method, and duration of vitamin D supplementation are unknown. Additionally, neuropathy repair requires HDVD supplementation to sustain adequate vitamin D levels. This once-a-month intramuscular method avoids daily medication; therefore, compliance is high. This study will be the first randomized controlled trial in China to analyze the efficacy and safety of HDVD supplementation for patients with T2DM and DSPN and will provide new ideas for pharmacological research and clinical treatment of diabetic neuropathy. Clinical trial registration: https://www.chictr.org.cn/, identifier ChiCTR2200062266.


Asunto(s)
Diabetes Mellitus Tipo 2 , Polineuropatías , Deficiencia de Vitamina D , Humanos , Vitamina D/uso terapéutico , Diabetes Mellitus Tipo 2/complicaciones , Método Doble Ciego , Vitaminas/uso terapéutico , Deficiencia de Vitamina D/complicaciones , Polineuropatías/complicaciones , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
2.
Drug Metab Dispos ; 48(12): 1257-1263, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33051247

RESUMEN

Pharmacological interventions for hepatocellular carcinoma (HCC) are hindered by complex factors, and rational combination therapy may be developed to improve therapeutic outcomes. Very recently, we have identified a bioengineered microRNA let-7c-5p (or let-7c) agent as an effective inhibitor against HCC in vitro and in vivo. In this study, we sought to identify small-molecule drugs that may synergistically act with let-7c against HCC. Interestingly, we found that let-7c exhibited a strong synergism with 5-fluorouracil (5-FU) in the inhibition of HCC cell viability as manifested by average combination indices of 0.3 and 0.5 in Hep3B and Huh7 cells, respectively. By contrast, coadministration of let-7c with doxorubicin or sorafenib inhibited HCC cell viability with, rather surprisingly, no or minimal synergy. Further studies showed that protein levels of multidrug resistance-associated protein (MRP) ATP-binding cassette subfamily C member 5 (MRP5/ABCC5), a 5-FU efflux transporter, were reduced around 50% by let-7c in HCC cells. This led to a greater degree of intracellular accumulation of 5-FU in Huh7 cells as well as the second messenger cyclic adenosine monophosphate, an endogenous substrate of MRP5. Since 5-FU is an irreversible inhibitor of thymidylate synthetase (TS), we investigated the interactions of let-7c with 5-FU at pharmacodynamic level. Interestingly, our data revealed that let-7c significantly reduced TS protein levels in Huh7 cells, which was associated with the suppression of upstream transcriptional factors as well as other regulatory factors. Collectively, these results indicate that let-7c interacts with 5-FU at both pharmacokinetic and pharmacodynamic levels, and these findings shall offer insight into molecular mechanisms of synergistic drug combinations. SIGNIFICANCE STATEMENT: Combination therapy is a common strategy that generally involves pharmacodynamic interactions. After identifying a strong synergism between let-7c-5p and 5-fluorouracil (5-FU) against hepatocellular carcinoma cell viability, we reveal the involvement of both pharmacokinetic and pharmacodynamic mechanisms. In particular, let-7c enhances 5-FU exposure (via suppressing ABCC5/MRP5 expression) and cotargets thymidylate synthase with 5-FU (let-7c reduces protein expression, whereas 5-FU irreversibly inactivates enzyme). These findings provide insight into developing rational combination therapies based on pharmacological mechanisms.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Carcinoma Hepatocelular/tratamiento farmacológico , Fluorouracilo/farmacocinética , Neoplasias Hepáticas/tratamiento farmacológico , MicroARNs/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Fluorouracilo/administración & dosificación , Regulación Neoplásica de la Expresión Génica , Ingeniería Genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , MicroARNs/administración & dosificación , MicroARNs/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo
3.
ACS Nano ; 14(4): 4265-4275, 2020 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-32160460

RESUMEN

Development of highly effective approaches to desirable photothermal conversion agents is particularly valuable. Herein, we report a concept, namely, bond stretching vibration-induced photothermy, that serves as a mechanism to construct advanced photothermal conversion agents. As a proof-of-concept, two compounds (DCP-TPA and DCP-PTPA) with donor-acceptor (D-A) structures were synthesized. The bond stretching vibration of the pyrazine-containing unit in these molecules is vigorous and insensitive to the external environmental restraint, which efficiently transforms the absorbed photons to dark-state heat energy. The nanoparticles (NPs) of DCP-TPA and DCP-PTPA show rather high photothermal conversion efficiency (52% and 59%) and stronger photoacoustic (PA) signal than commercial methylene blue and reported high-performance semiconducting polymer nanoparticles. The DCP-PTPA NPs perform better than DCP-TPA NPs in terms of photothermal conversion, PA signal production, and in vivo PA tumor imaging because of the increased bond stretching vibration in the former molecule.


Asunto(s)
Nanopartículas , Técnicas Fotoacústicas , Fototerapia , Polímeros , Vibración
4.
Acta Pharm Sin B ; 9(3): 639-647, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31193825

RESUMEN

Drug-metabolizing enzymes, transporters, and nuclear receptors are essential for the absorption, distribution, metabolism, and excretion (ADME) of drugs and xenobiotics. MicroRNAs participate in the regulation of ADME gene expression via imperfect complementary Watson-Crick base pairings with target transcripts. We have previously reported that Cytochrome P450 3A4 (CYP3A4) and ATP-binding cassette sub-family G member 2 (ABCG2) are regulated by miR-27b-3p and miR-328-3p, respectively. Here we employed our newly established RNA bioengineering technology to produce bioengineered RNA agents (BERA), namely BERA/miR-27b-3p and BERA/miR-328-3p, via fermentation. When introduced into human cells, BERA/miR-27b-3p and BERA/miR-328-3p were selectively processed to target miRNAs and thus knock down CYP3A4 and ABCG2 mRNA and their protein levels, respectively, as compared to cells treated with vehicle or control RNA. Consequently, BERA/miR-27b-3p led to a lower midazolam 1'-hydroxylase activity, indicating the reduction of CYP3A4 activity. Likewise, BERA/miR-328-3p treatment elevated the intracellular accumulation of anticancer drug mitoxantrone, a classic substrate of ABCG2, hence sensitized the cells to chemotherapy. The results indicate that biologic miRNA agents made by RNA biotechnology may be applied to research on miRNA functions in the regulation of drug metabolism and disposition that could provide insights into the development of more effective therapies.

5.
BMC Nephrol ; 19(1): 160, 2018 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-29973184

RESUMEN

BACKGROUND: Hypokalemia is one of the most common clinical electrolyte imbalance problems, and thyrotoxic periodic paralysis (TPP) is a leading cause of presentation to the emergency department. Low renal potassium secretion rates, a normal acid-base balance in the blood, and hyperthyroidism are the hallmarks of suspected TPP. CASE PRESENTATION: Here we report the case of a 36-year-old man who presented to the emergency department with a sudden onset of acute muscle weakness at 5 h prior to admission. Biochemistry tests revealed hypokalemia with hyperthyroidism and renal potassium wasting. TPP was initially not favored due to the presence of renal potassium wasting. However, his serum potassium level rebounded rapidly within several hours after potassium supplementation, indicating that the intracellular shifting of potassium ions was the main etiology for his hypokalemia. The early stage of TPP development may have contributed to this paradox. CONCLUSION: Therefore, it is premature to rule out TPP based on the presentation of high renal potassium secretion rates alone. This finding may result in an incorrect impression being made in the early stage of TTP and may consequently lead to an inappropriate potassium supplementation policy.


Asunto(s)
Hipertiroidismo/sangre , Hipopotasemia/sangre , Debilidad Muscular/sangre , Parálisis/sangre , Potasio/sangre , Adulto , Diagnóstico Diferencial , Humanos , Hipertiroidismo/complicaciones , Hipertiroidismo/diagnóstico , Hipopotasemia/complicaciones , Hipopotasemia/diagnóstico , Masculino , Debilidad Muscular/complicaciones , Debilidad Muscular/diagnóstico , Parálisis/complicaciones , Parálisis/diagnóstico
6.
Biomed Mater ; 12(3): 035004, 2017 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-28580902

RESUMEN

The development of a new generation of biomaterials with high osteogenic ability for treatment of osteoporotic fractures is being intensively investigated. The objective of this paper was to investigate new bone formation in an ovariectomized rat (OVX rat) calvarial model of critical size bone defects filled with Sr-containing α-calcium sulfate hemihydrate (SrCSH) cement compared to an α-calcium sulfate hemihydrate (α-CSH) cement and empty defect. X-ray diffraction analysis verified the partial substitution of Sr2+ for Ca2+ did not change the phase composition of α-CSH. Scanning electron microscopy showed that Sr-substituted α-CSH significantly increased the surface roughness. The effects of Sr substitution on the biological properties of SrCSH cement were evaluated by adhesion, proliferation, alkaline phosphatase (ALP) activity of osteoblast-like cells MC3T3-E1. The results showed that SrCSHs enhanced MC3T3-E1 cell proliferation, differentiation, and ALP activity. Furthermore, SrCSH cement was used to repair critical-sized OVX rat calvarial defects. The in vivo results revealed that SrCSH had good osteogenic capability and stimulated new blood vessel formation in a critical sized OVX calvarial defect within 12 weeks, suggesting that SrCSH cement has more potential for application in bone tissue regeneration.


Asunto(s)
Sustitutos de Huesos/síntesis química , Sustitutos de Huesos/uso terapéutico , Sulfato de Calcio/química , Osteogénesis , Fracturas Osteoporóticas/terapia , Fracturas Craneales/terapia , Estroncio/química , Células 3T3 , Animales , Femenino , Ensayo de Materiales , Ratones , Fracturas Osteoporóticas/patología , Fracturas Osteoporóticas/fisiopatología , Ovariectomía , Ratas , Ratas Sprague-Dawley , Fracturas Craneales/patología , Fracturas Craneales/fisiopatología , Resultado del Tratamiento
7.
Oncotarget ; 8(19): 30742-30755, 2017 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-28415566

RESUMEN

Metastasis is a major cause of mortality for cancer patients and remains as the greatest challenge in cancer therapy. Driven by multiple factors, metastasis may not be controlled by the inhibition of single target. This study was aimed at assessing the hypothesis that drugs could be rationally combined to co-target critical DNA, RNA and protein molecules to achieve "saturation attack" against metastasis. Independent actions of the model drugs DNA-intercalating doxorubicin, RNA-interfering miR-34a and protein-inhibiting sorafenib on DNA replication, RNA translation and protein kinase signaling in highly metastatic, human osteosarcoma 143B cells were demonstrated by the increase of γH2A.X foci formation, reduction of c-MET expression and inhibition of Erk1/2 phosphorylation, respectively, and optimal effects were found for triple-drug combination. Consequently, triple-drug treatment showed a strong synergism in suppressing 143B cell proliferation and the greatest effects in reducing cell invasion. Compared to single- and dual-drug treatment, triple-drug therapy suppressed pulmonary metastases and orthotopic osteosarcoma progression to significantly greater degrees in orthotopic osteosarcoma xenograft/spontaneous metastases mouse models, while none showed significant toxicity. In addition, triple-drug therapy improved the overall survival to the greatest extent in experimental metastases mouse models. These findings demonstrate co-targeting of DNA, RNA and protein molecules as a novel therapeutic strategy for the treatment of metastasis.


Asunto(s)
Neoplasias Óseas/patología , Neoplasias Pulmonares/secundario , Terapia Molecular Dirigida , Osteosarcoma/patología , Animales , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Terapia Combinada , ADN , Modelos Animales de Enfermedad , Doxorrubicina/farmacología , Sinergismo Farmacológico , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/terapia , Ratones , MicroARNs/genética , Niacinamida/análogos & derivados , Niacinamida/farmacología , Osteosarcoma/genética , Osteosarcoma/metabolismo , Compuestos de Fenilurea/farmacología , ARN , Sorafenib , Ensayos Antitumor por Modelo de Xenoinjerto
9.
J Cutan Pathol ; 36(3): 355-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19220632

RESUMEN

Necrolytic acral erythema is a newly described entity characterized by sharply demarcated scaly plaques on the dorsum of the hands and feet. More than 30 patients have been reported since 1996, all of whom had anti-hepatitis C virus antibody. A 32-year-old Taiwanese woman had been diagnosed with and treated for systemic lupus erythematosus with lupus nephritis about 10 years earlier. Soon thereafter, she noted several well-demarcated keratotic plaques with erythematous borders on her feet, with sparing of the soles. Histopathology showed diffuse parakeratosis with a neutrophil infiltrate, hypogranulosis, pale upper keratinocytes, scattered and grouped dyskeratotic cells, psoriasiform hyperplasia and a mild lymphocytic infiltrate in the upper dermis. The diagnosis was made after three biopsies. The lesions regularly worsened just before and during menstruation, but patch and intradermal tests for progesterone and estrogen were negative. There was no evidence of either hepatitis B or hepatitis C infection. The lesions did not respond to treatment with zinc. The rash regressed spontaneously when corticosteroids were stopped and recurred when they were restarted, finally resolving completely after she was treated with high-dose pulse steroids for her lupus.


Asunto(s)
Eritema/patología , Hepatitis C , Paraqueratosis/patología , Adulto , Pueblo Asiatico , Eritema/inducido químicamente , Femenino , Humanos , Hiperplasia/inducido químicamente , Hiperplasia/patología , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/patología , Nefritis Lúpica/dietoterapia , Nefritis Lúpica/patología , Linfocitos/patología , Necrosis/inducido químicamente , Necrosis/patología , Paraqueratosis/inducido químicamente , Piel/patología , Esteroides/administración & dosificación , Esteroides/efectos adversos , Taiwán
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA