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1.
Sci Adv ; 10(16): eadl1856, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640241

RESUMO

Continuous glucose monitoring systems (CGMs) are critical toward closed-loop diabetes management. The field's progress urges next-generation CGMs with enhanced antinoise ability, reliability, and wearability. Here, we propose a coin-sized, fully integrated, and wearable CGM, achieved by holistically synergizing state-of-the-art interdisciplinary technologies of biosensors, minimally invasive tools, and hydrogels. The proposed CGM consists of three major parts: (i) an emerging biochemical signal amplifier, the organic electrochemical transistor (OECT), improving the signal-to-noise ratio (SNR) beyond traditional electrochemical sensors; (ii) a microneedle array to facilitate subcutaneous glucose sampling with minimized pain; and (iii) a soft hydrogel to stabilize the skin-device interface. Compared to conventional CGMs, the OECT-CGM offers a high antinoise ability, tunable sensitivity and resolution, and comfort wearability, enabling personalized glucose sensing for future precision diabetes health care. Last, we discuss how OECT technology can help push the limit of detection of current wearable electrochemical biosensors, especially when operating in complicated conditions.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus , Humanos , Automonitorização da Glicemia , Glicemia , Monitoramento Contínuo da Glicose , Reprodutibilidade dos Testes , Glucose , Diabetes Mellitus/diagnóstico
2.
J Cell Mol Med ; 28(7): e18240, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38509741

RESUMO

Growing evidence supports the analgesic efficacy of electroacupuncture (EA) in managing chronic neuropathic pain (NP) in both patients and NP models induced by peripheral nerve injury. However, the underlying mechanisms remain incompletely understood. Ferroptosis, a novel form of programmed cell death, has been found to be activated during NP development, while EA has shown potential in promoting neurological recovery following acute cerebral injury by targeting ferroptosis. In this study, to investigate the detailed mechanism underlying EA intervention on NP, male Sprague-Dawley rats with chronic constriction injury (CCI)-induced NP model received EA treatment at acupoints ST36 and GV20 for 14 days. Results demonstrated that EA effectively attenuated CCI-induced pain hypersensitivity and mitigated neuron damage and loss in the spinal cord of NP rats. Moreover, EA reversed the oxidative stress-mediated spinal ferroptosis phenotype by upregulating reduced expression of xCT, glutathione peroxidase 4 (GPX4), ferritin heavy chain (FTH1) and superoxide dismutase (SOD) levels, and downregulating increased expression of acyl-CoA synthetase long-chain family member 4 (ACSL4), malondialdehyde levels and iron overload. Furthermore, EA increased the immunofluorescence co-staining of GPX4 in neurons cells of the spinal cord of CCI rats. Mechanistic analysis unveiled that the inhibition of antioxidant pathway of Nrf2 signalling via its specific inhibitor, ML385, significantly countered EA's protective effect against neuronal ferroptosis in NP rats while marginally diminishing its analgesic effect. These findings suggest that EA treatment at acupoints ST36 and GV20 may protect against NP by inhibiting neuronal ferroptosis in the spinal cord, partially through the activation of Nrf2 signalling.


Assuntos
Eletroacupuntura , Ferroptose , Neuralgia , Humanos , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Eletroacupuntura/métodos , Fator 2 Relacionado a NF-E2/metabolismo , Neuralgia/metabolismo , Neurônios/metabolismo , Medula Espinal/metabolismo , Analgésicos
3.
Biomed Rep ; 20(2): 30, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38259587

RESUMO

The present study aimed to evaluate the efficacy and safety of bloodletting puncture and cupping (BLP-C) in postherpetic neuralgia (PHN) and to provide guidance for clinical treatment. Randomized controlled trials (RCTs) of BLP-C therapy in PHN were systematically searched in eight databases from inception to September 2022. Literature screening, data extraction and quality assessment were performed by two independent researchers. Dichotomous and continuous variables were pooled using the risk ratio (RR) and weighted mean difference (WMD), respectively. A total of 13 studies involving 1,129 patients with PHN (571 in the experimental group and 558 in the control group) were included in the present meta-analysis. Overall efficacy (RR=1.21, 95% CI: 1.15 to 1.28, P<0.00001), VAS score (WMD=-1.10, 95% CI: -1.31 to -0.90, P<0.00001) and PSQI score (WMD=-2.42, 95% CI: -2.87 to -1.96, P<0.0001) were significantly different between the BLP-C group and Western medicine group. Furthermore, subgroup analysis demonstrated that BLP-C alone or combined with other traditional Chinese medicines was more effective than Western medicine in PHN. A total of four RCTs mentioned adverse reactions, most of which were in the Western medicine group and were relieved after treatment discontinuation. In conclusion, BLP-C is superior to Western medicine in relieving pain and improving the sleep quality of patients with PHN with a lower incidence of adverse effects.

4.
Nat Commun ; 14(1): 5699, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709778

RESUMO

Phototherapy of deep tumors still suffers from many obstacles, such as limited near-infrared (NIR) tissue penetration depth and low accumulation efficiency within the target sites. Herein, stimuli-sensitive tumor-targeted photodynamic nanoparticles (STPNs) with persistent luminescence for the treatment of deep tumors are reported. Purpurin 18 (Pu18), a porphyrin derivative, is utilized as a photosensitizer to produce persistent luminescence in STPNs, while lanthanide-doped upconversion nanoparticles (UCNPs) exhibit bioimaging properties and possess high photostability that can enhance photosensitizer efficacy. STPNs are initially stimulated by NIR irradiation before intravenous administration and accumulate at the tumor site to enter the cells through the HER2 receptor. Due to Pu18 afterglow luminescence properties, STPNs can continuously generate ROS to inhibit NFκB nuclear translocation, leading to tumor cell apoptosis. Moreover, STPNs can be used for diagnostic purposes through MRI and intraoperative NIR navigation. STPNs exceptional antitumor properties combined the advantages of UCNPs and persistent luminescence, representing a promising phototherapeutic strategy for deep tumors.


Assuntos
Carcinoma in Situ , Neoplasias da Vesícula Biliar , Nanopartículas , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Luminescência
5.
Nat Commun ; 14(1): 4628, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532754

RESUMO

Chemotherapy remains as the first-choice treatment option for triple-negative breast cancer (TNBC). However, the limited tumor penetration and low cellular internalization efficiency of current nanocarrier-based systems impede the access of anticancer drugs to TNBC with dense stroma and thereby greatly restricts clinical therapeutic efficacy, especially for TNBC bone metastasis. In this work, biomimetic head/hollow tail nanorobots were designed through a site-selective superassembly strategy. We show that nanorobots enable efficient remodeling of the dense tumor stromal microenvironments (TSM) for deep tumor penetration. Furthermore, the self-movement ability and spiky head markedly promote interfacial cellular uptake efficacy, transvascular extravasation, and intratumoral penetration. These nanorobots, which integrate deep tumor penetration, active cellular internalization, near-infrared (NIR) light-responsive release, and photothermal therapy capacities into a single nanodevice efficiently suppress tumor growth in a bone metastasis female mouse model of TNBC and also demonstrate potent antitumor efficacy in three different subcutaneous tumor models.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias de Mama Triplo Negativas , Animais , Humanos , Camundongos , Feminino , Neoplasias de Mama Triplo Negativas/terapia , Neoplasias de Mama Triplo Negativas/patologia , Biomimética , Linhagem Celular Tumoral , Fototerapia , Microambiente Tumoral
6.
Adv Sci (Weinh) ; 10(8): e2202519, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36683155

RESUMO

Low persistence, metabolic dysfunction in microenvironment, and tumor-derived immunosuppression of Natural killer (NK) cells in patients are greatly limited the successful clinical application of NK cell-based cancer immunotherapy. Interestingly, herein that human serum albumin-encapsulated black phosphorus quantum dots (BPQDs@HSA) can effectively augment antitumor efficacy of clinical patients-derived NK cell immunotherapy is found. As the donor of phosphate group, BPQDs@HSA binds with the protein of phosphatidylinositol 4-phosphate 5-kinase type-1 gamma (PIP5K1A) and activates the downstream PI3K-Akt and mTOR signaling pathways to reprogram cell metabolism of glycolysis and further promote the oxidative phosphorylation, sequentially maintains the cell viability and immunity of NK cells. And multiomics analysis is therefore conducted to reveal the underlying immunoregulation mechanisms, and that BPQDs@HSA can interact with the Toll-like receptor (TLR) on the NK cell surface and increase the expression level of mTOR, and thus activate downstream NF-κB signalling pathways to regulate cytokine secretion and enhance immune tumoricidal is found. BPQDs@HSA can also enhance immune surveillance, relieve immune suppression, and inhibit tumor immune escape. Collectively, this study not only demonstrates a successful strategy for nanomedicine-potentiated immune-cancer therapy, but also sheds light on the understanding of interface between nanomedicine and immune cells activation.


Assuntos
Neoplasias , Pontos Quânticos , Humanos , Fósforo , Fosfatidilinositol 3-Quinases , Células Matadoras Naturais , Imunoterapia , Neoplasias/patologia , Serina-Treonina Quinases TOR , Microambiente Tumoral
7.
Artigo em Inglês | MEDLINE | ID: mdl-35469162

RESUMO

Gynura procumbens is a traditional herb and food extensively cultivated in China and Southeast Asian countries. In this work, the crude extract (CE) of G. procumbens was purified with macroporous resin to obtain the refined fraction, and its anti-inflammatory activity was compared with that of CE. Moreover, the detailed mechanisms of anti-inflammatory activity were also investigated for the first time. The results indicated that CE was more effective in anti-inflammatory activity and it could reduce the secretion of NO, TNF-α, and PGE2 via decreasing the iNOS, TNF-α, and COX-2 genes transcription and related proteins translation, which were associated with the inhibition of AP-1 and NF-κB nuclear translocation and downregulation of PI3K/Akt and MAPK signaling pathways. In conclusion, the extract of G. procumbens has a promising potential in inflammation-related disorders alleviation, and these findings could provide the basis for the comprehensive utilization of G. procumbens and the new functional food development.

8.
Sci Rep ; 12(1): 3592, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246558

RESUMO

Head and neck cancer is the sixth most common cancer in the world, with more than 300,000 deaths attributed to the disease annually. Aggressive surgical resection often with adjuvant chemoradiation is the cornerstone of treatment. However, the necessary chemoradiation treatment can result in collateral damage to adjacent vital structures causing a profound impact on quality of life. Here, we present a novel polymer of poly(lactic-co-glycolic) acid and polyvinyl alcohol that can serve as a versatile multidrug delivery platform as well as for detection on cross-sectional imaging while functioning as a fiduciary marker for postoperative radiotherapy and radiotherapeutic dosing. In a mouse xenograft model, the dual-layered polymer composed of calcium carbonate/thymoquinone was used for both polymer localization and narrow-field infusion of a natural therapeutic compound. A similar approach can be applied in the treatment of head and neck cancer patients, where immunotherapy and traditional chemotherapy can be delivered simultaneously with independent release kinetics.


Assuntos
Neoplasias de Cabeça e Pescoço , Polímeros , Animais , Quimiorradioterapia Adjuvante , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Camundongos , Polímeros/química , Qualidade de Vida
9.
Artigo em Inglês | MEDLINE | ID: mdl-32255276

RESUMO

Cancer immunotherapy aims to leverage the immune system to suppress the growth of tumors and to inhibit metastasis. The recent promising clinical outcomes associated with cancer immunotherapy have prompted research and development efforts towards enhancing the efficacy of immune checkpoint blockade, cancer vaccines, cytokine therapy, and adoptive T cell therapy. Advancements in biomaterials, nanomedicine, and micro-/nano-technology have facilitated the development of enhanced local delivery systems for cancer immunotherapy, which can enhance treatment efficacy while minimizing toxicity. Furthermore, locally administered cancer therapies that combine immunotherapy with chemotherapy, radiotherapy, or phototherapy have the potential to achieve synergistic antitumor effects. Herein, the latest studies on local delivery systems for cancer immunotherapy are surveyed, with an emphasis on the therapeutic benefits associated with the design of biomaterials and nanomedicines. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.


Assuntos
Sistemas de Liberação de Medicamentos , Imunoterapia , Nanomedicina , Neoplasias/terapia , Animais , Materiais Biocompatíveis , Humanos , Camundongos
10.
Adv Mater ; 31(23): e1900192, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30916367

RESUMO

Chimeric antigen receptor (CAR)-redirected T lymphocytes (CAR T cells) show modest therapeutic efficacy in solid tumors. The desmoplastic structure of the tumor and the immunosuppressive tumor microenvironment usually account for the reduced efficacy of CAR T cells in solid tumors. Mild hyperthermia of the tumor reduces its compact structure and interstitial fluid pressure, increases blood perfusion, releases antigens, and promotes the recruitment of endogenous immune cells. Therefore, the combination of mild hyperthermia with the adoptive transfer of CAR T cells can potentially increase the therapeutic index of these cells in solid tumors. It is found that the chondroitin sulfate proteoglycan-4 (CSPG4)-specific CAR T cells infused in Nod scid gamma mice engrafted with the human melanoma WM115 cell line have superior antitumor activity after photothermal ablation of the tumor. The findings suggest that photothermal therapy facilitates the accumulation and effector function of CAR T cells within solid tumors.


Assuntos
Antígenos/metabolismo , Hipertermia Induzida , Imunoterapia Adotiva/métodos , Fototerapia/métodos , Proteoglicanas/metabolismo , Linfócitos T/metabolismo , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Terapia Combinada , Feminino , Xenoenxertos , Humanos , Verde de Indocianina/química , Melanoma/patologia , Melanoma/terapia , Proteínas de Membrana/metabolismo , Camundongos SCID , Nanopartículas/química , Fármacos Fotossensibilizantes/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia , Linfócitos T/transplante
11.
Nat Commun ; 9(1): 4241, 2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30315173

RESUMO

By delivering the concept of clean hydrogen energy and green catalysis to the biomedical field, engineering of hydrogen-generating nanomaterials for treatment of major diseases holds great promise. Leveraging virtue of versatile abilities of Pd hydride nanomaterials in high/stable hydrogen storage, self-catalytic hydrogenation, near-infrared (NIR) light absorption and photothermal conversion, here we utilize the cubic PdH0.2 nanocrystals for tumour-targeted and photoacoustic imaging (PAI)-guided hydrogenothermal therapy of cancer. The synthesized PdH0.2 nanocrystals have exhibited high intratumoural accumulation capability, clear NIR-controlled hydrogen release behaviours, NIR-enhanced self-catalysis bio-reductivity, high NIR-photothermal effect and PAI performance. With these unique properties of PdH0.2 nanocrystals, synergetic hydrogenothermal therapy with limited systematic toxicity has been achieved by tumour-targeted delivery and PAI-guided NIR-controlled release of bio-reductive hydrogen as well as generation of heat. This hydrogenothermal approach has presented a cancer-selective strategy for synergistic cancer treatment.


Assuntos
Hidrogênio/química , Fototerapia/métodos , Catálise , Nanopartículas/química , Nanoestruturas/química , Técnicas Fotoacústicas , Espectroscopia de Luz Próxima ao Infravermelho
12.
ACS Nano ; 12(6): 5995-6005, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29786420

RESUMO

The facultative anaerobe Salmonella strain VNP20009 selectively colonizes into tumors following systemic injection due to its preference for the hypoxia in the tumor cores. However, the phase 1 clinical trial of VNP20009 has been terminated mainly due to its weak antitumor effects and exhibition of dose-dependent toxicity. Here, we leveraged the advantages of VNP20009 biotherapy together with polydopamine-mediated photothermal therapy in order to enhance the antitumor efficacy toward malignant melanoma. VNP20009 was coated with polydopamine via oxidation and self-polymerization, which was then injected into tumor-bearing mice via the tail vein. Polydopamine-coated VNP20009 targeted hypoxic areas of the solid tumors, and near-infrared laser irradiation of the tumors induced heating due to polydopamine. This combined approach eliminated the tumors without relapse or metastasis with only one injection and laser irradiation. More importantly, we found both VNP and pDA potentiate the therapeutic ability of each other, resulting in a superior anticancer effect.


Assuntos
Antineoplásicos/farmacologia , Hipóxia/metabolismo , Indóis/farmacologia , Melanoma Experimental/terapia , Fototerapia , Polímeros/farmacologia , Salmonella/metabolismo , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Indóis/efeitos adversos , Indóis/metabolismo , Lasers , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Polímeros/efeitos adversos , Polímeros/metabolismo , Salmonella/crescimento & desenvolvimento , Distribuição Tecidual , Células Tumorais Cultivadas
13.
J Chromatogr Sci ; 56(2): 108-114, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29045617

RESUMO

High-speed counter-current chromatography (HSCCC) combined with macroporous resin (MR) column was successfully applied to the isolation and purification of four flavonoid glycosides from the medicinal herb Lotus plumule (LP). A polar two-phase solvent system composed of ethyl acetate-n-butanol-water (1:2:3, v/v/v) was selected by high-performance liquid chromatography (HPLC) and run on a preparative scale where the lower aqueous phase was used as the mobile phase with a head-to-tail elution mode. Quercetin-3-O-ß-D-glucopyranoside (15 mg), isorhamnetin-3-O-ß-D-glucopyranoside (13 mg), apigenin 6-C-ß-D-glucopyranosyl-8-C-α-L-arabinopyranoside (18 mg) and apigenin 6,8-di-C-ß-D-glucopyranoside (48 mg) were obtained in a one-step HSCCC separation from 240 mg of the sample. The purity of each compound was over 95% as determined by HPLC. Chemical structures of the isolated compounds were identified by electrospray ionization mass spectrometry (ESI-MS-MS) and nuclear magnetic resonance (NMR) methods. Moreover, the four compounds were isolated from LP for the first time.


Assuntos
Distribuição Contracorrente/métodos , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Nelumbo/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Glicosídeos/análise , Espectroscopia de Ressonância Magnética , Caules de Planta/química , Espectrometria de Massas por Ionização por Electrospray
14.
Enzyme Microb Technol ; 93-94: 182-190, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27702480

RESUMO

Developing a strain with high docosahexaenoic acid (DHA) yield and stable fermenting-performance is an imperative way to improve DHA production using Aurantiochytrium sp., a microorganism with two fatty acid synthesis pathways: polyketide synthase (PKS) pathway and Type I fatty acid synthase (FAS) pathway. This study investigated the growth and metabolism response of Aurantiochytrium sp. CGMCC 6208 to two inhibitors of enoyl-ACP reductase of Type II FAS pathway (isoniazid and triclosan), and proposed a method of screening high DHA yield Aurantiochytrium sp. strains with heavy ion mutagenesis and pre-selection by synergistic usage of cold stress (4°C) and FAS inhibitors (triclosan and isoniazid). Results showed that (1) isoniazid and triclosan have positive effects on improving DHA level of cells; (2) mutants from irradiation dosage of 120Gy yielded more DHA compared with cells from 40Gy, 80Gy treatment and wild type; (3) DHA contents of mutants pre-selected by inhibitors of enoyl-ACP reductase of Type II FAS pathway (isoniazid and triclosan)at 4°C, were significantly higher than that of wild type; (4) compared to the wild type, the DHA productivity and yield of a mutant (T-99) obtained from Aurantiochytrium sp. CGMCC 6208 by the proposed method increased by 50% from 0.18 to 0.27g/Lh and 30% from 21 to 27g/L, respectively. In conclusion, this study developed a feasible method to screen Aurantiochytrium sp. with high DHA yield by a combination of heavy-ion mutagenesis and mutant-preselection by FAS inhibitors and cold stress.


Assuntos
Ácidos Docosa-Hexaenoicos/biossíntese , Enoil-(Proteína de Transporte de Acila) Redutase (NADPH, B-Específica)/antagonistas & inibidores , Estramenópilas/genética , Estramenópilas/metabolismo , Temperatura Baixa , Suplementos Nutricionais , Enoil-(Proteína de Transporte de Acila) Redutase (NADPH, B-Específica)/genética , Enoil-(Proteína de Transporte de Acila) Redutase (NADPH, B-Específica)/metabolismo , Inibidores Enzimáticos/farmacologia , Ácido Graxo Sintase Tipo II/antagonistas & inibidores , Fermentação , Íons , Isoniazida/farmacologia , Mutagênese , Estramenópilas/efeitos dos fármacos , Estresse Fisiológico , Triclosan/farmacologia
15.
Biomaterials ; 96: 1-10, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27131597

RESUMO

Direct delivery of cytokines using nanocarriers holds great promise for cancer therapy. However, the nanometric scale of the vehicles made them susceptible to size-dependent endocytosis, reducing the plasma membrane-associated apoptosis signaling. Herein, we report a tumor microenvironment-responsive and transformable nanocarrier for cell membrane targeted delivery of cytokine. This formulation is comprised of a phospholipase A2 (PLA2) degradable liposome as a shell, and complementary DNA nanostructures (designated as nanoclews) decorated with cytokines as the cores. Utilizing the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) as a model cytokine, we demonstrate that the TRAIL loaded DNA nanoclews are capable of transforming into nanofibers after PLA2 activation. The nanofibers with micro-scaled lengths efficiently present the loaded TRAIL to death receptors on the cancer cell membrane and amplified the apoptotic signaling with reduced TRAIL internalization.


Assuntos
Membrana Celular/metabolismo , Citocinas/administração & dosagem , DNA/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Hidrodinâmica , Lipossomos , Nanopartículas/ultraestrutura , Níquel/química , Tamanho da Partícula , Fosfatidilcolinas/química , Fosfolipases A2/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia
16.
Exp Ther Med ; 9(3): 987-991, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25667665

RESUMO

The aim of this study was to investigate the analgesic mechanism of electroacupuncture (EA) in the treatment of neuropathological pain. A total of 60 Sprague-Dawley rats were randomly divided into three groups, namely the spinal nerve ligation (SNL), electroacupuncture (SNL + EA) and normal control groups, with 20 rats in each group. The up-down method was used to determine the bipedal 50% mechanical paw withdrawal threshold (PWT). The ultrastructure of the injured-side L5 nerve root (n=6) was observed by electron microscopy. The mRNA levels of brain-derived neurotrophic factor (BDNF) and purinergic receptor P2X, ligand-gated ion channel 4 (P2X4) in the spinal cord (n=14) were determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The postoperative PWT of the injured-side hindpaw in the SNL group at each time point was lower than that in the control group (P<0.01); there were differences of statistical significance between the PWT values of the SNL + EA and SNL groups on postoperative days 14 and 21 (P<0.05). Postoperatively, the PWT of the hindpaw on the uninjured-side was significantly lower in the SNL group when compared with that of the control group on days 10, 14 and 21 (P<0.05). Following the EA treatment, axonal demyelination was reduced and vascular proliferation was observed within the visual field. In addition, following the EA treatment, BDNF expression levels in the spinal dorsal horn increased (P<0.05), while the expression of P2X4 was not different from that in the SNL group. EA exerted an analgesic effect on the SNL model in a time-dependent manner, and improved the blood supply to the nerve root. Following the EA treatment, the expression of P2X4 did not change significantly compared with that in the SNL group, whereas the spinal secretion of BDNF increased. However, the exact mechanism requires further study.

17.
Biomaterials ; 34(23): 5792-801, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23660251

RESUMO

Immuno-isolation of islets has the potential to enable the replacement of pancreatic function in diabetic patients. However, host response to the encapsulated islets frequently leads to fibrotic overgrowth with subsequent impairment of the transplanted grafts. Here, we identified and incorporated anti-inflammatory agents into islet-containing microcapsules to address this challenge. In vivo subcutaneous screening of 16 small molecule anti-inflammatory drugs was performed to identify promising compounds that could minimize the formation of fibrotic cell layers. Using parallel non-invasive fluorescent and bioluminescent imaging, we identified dexamethasone and curcumin as the most effective drugs in inhibiting the activities of inflammatory proteases and reactive oxygen species in the host response to subcutaneously injected biomaterials. Next, we demonstrated that co-encapsulating curcumin with pancreatic rat islets in alginate microcapsules reduced fibrotic overgrowth and improved glycemic control in a mouse model of chemically-induced type I diabetes. These results showed that localized administration of anti-inflammatory drug can improve the longevity of encapsulated islets and may facilitate the translation of this technology toward a long-term cure for type I diabetes.


Assuntos
Anti-Inflamatórios/uso terapêutico , Cápsulas/química , Diabetes Mellitus Experimental/terapia , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/imunologia , Animais , Anti-Inflamatórios/farmacologia , Catepsinas/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Fibrose , Ilhotas Pancreáticas/efeitos dos fármacos , Ácido Láctico/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/uso terapêutico
18.
Sci Rep ; 3: 1537, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23524384

RESUMO

Quantum dots (QDs) have attracted increasing interest in bioimaging and sensing. Here, we report a biosensor of complex I using ubiquinone-terminated disulphides with different alkyl spacers (QnNS, n = 2, 5 and 10) as surface-capping ligands to functionalise CdSe/ZnS QDs. The enhancement or quenching of the QD bioconjugates fluorescence changes as a function of the redox state of QnNS, since QDs are highly sensitive to the electron-transfer processes. The bioconjugated QnNS-QDs emission could be modulated by complex I in the presence of NADH, which simulates an electron-transfer system part of the mitochondrial respiratory chain, providing an in vitro and intracellular complex I sensor. Epidemiological studies suggest that Parkinson's patients have the impaired activity of complex I in the electron-transfer chain of mitochondria. We have demonstrated that the QnNS-QDs system could aid in early stage Parkinson's disease diagnosis and progression monitoring by following different complex I levels in SH-SY5Y cells.


Assuntos
Técnicas Biossensoriais , Complexo I de Transporte de Elétrons/metabolismo , Mitocôndrias/metabolismo , Pontos Quânticos , Ubiquinona/química , Cádmio/química , Técnicas Eletroquímicas , Transporte de Elétrons , Humanos , NAD/metabolismo , Oxirredução , Doença de Parkinson/diagnóstico , Doença de Parkinson/metabolismo , Respiração , Selênio/química , Zinco/química
19.
Int J Cardiol ; 162(3): 199-209, 2013 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22000973

RESUMO

BACKGROUND: Telomere signaling plays a role in regulating cardiomyocyte apoptosis during cardiac dysfunction. In this study, we investigated the effects of epigallocatechin gallate (EGCG), the major component of polyphenols in green tea, on telomere dependent apoptotic signal in pressure overload cardiac hypertrophy. METHODS AND RESULTS: Cardiac hypertrophy in rats was established by abdominal aortic constriction (AC). EGCG 50, 100 mg/kg, quercetin (Que) 100mg/kg, captopril (Cap) 50mg/kg, losartan (Los) 30 mg/kg and carvedilol (Carv) 30 mg/kg was intragastrically administered for 6 weeks. Three, five and 7 weeks after aortic constriction, the heart weight indices increased progressively. Malondialdehyde (MDA) contents progressively increased, while superoxide dismutase (SOD) activities decreased. Progressive cardiomyocyte apoptosis and telomere attrition were also found. Although no significant alteration of telomerase reverse transcriptase (TERT) mRNA was found till 7 weeks after aortic constriction, progressive upregulation of p53, c-myc and downregulation of bcl-2, telomere repeat-binding factor 2(TRF(2)) were seen. EGCG, quercetin, captopril, losartan and carvedilol markedly reduced heart weight indices and apoptotic cardiomyocyte in hypertrophic myocardium, but they had different effects on apoptotic related proteins bcl-2, p53 and c-myc. EGCG, quercetin and carvedilol, have potent antioxidant effects as evidenced by reduction of MDA contents and resumption of SOD activities. EGCG, quercetin and carvedilol could prevent telomere attrition and telomere repeat-binding factor 2 (TRF(2)) loss remarkably, whereas captopril and losartan had no effect on oxidative stress and telomere signal. CONCLUSIONS: Pressure overload induced cardiac hypertrophy initiates oxidative stress, induces telomere repeat-binding factor 2 loss and accelerates telomere shortening in hypertrophic myocardium. EGCG, quercetin and carvedilol with potent antioxidant effect, may inhibit cardiac myocyte apoptosis by preventing telomere shortening and telomere repeat-binding factor 2 (TRF(2)) loss.


Assuntos
Cardiomegalia/tratamento farmacológico , Catequina/análogos & derivados , Miócitos Cardíacos/efeitos dos fármacos , Polifenóis/uso terapêutico , Chá , Telômero/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Cardiomegalia/patologia , Catequina/isolamento & purificação , Catequina/farmacologia , Catequina/uso terapêutico , Masculino , Miócitos Cardíacos/patologia , Polifenóis/isolamento & purificação , Polifenóis/farmacologia , Ratos , Ratos Sprague-Dawley , Telômero/patologia
20.
Fitoterapia ; 82(3): 383-92, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21075176

RESUMO

This study aimed to evaluate the radioprotective effect of flavonoids extracted from the seeds of Astragalus complanatus R.Br. (FAC) and their protective mechanism against radiation damage. FAC increased the survival rate of mice and made the damaged organ injured by (60)Co γ-irradiation recovered to normal appearance with the mechanism of enhancing immune function and blood-producing function in vivo. The molecule mechanism of FAC against radiation is involved in the reduction of DNA injury and mutation in vitro. Eleven monomers of the FAC were analyzed by HPLC. These results seem to support the use of FAC in relieving radiation damage.


Assuntos
Astrágalo/química , Dano ao DNA/efeitos dos fármacos , Flavonoides/uso terapêutico , Fitoterapia , Extratos Vegetais/uso terapêutico , Lesões por Radiação/tratamento farmacológico , Protetores contra Radiação/uso terapêutico , Animais , Feminino , Flavonoides/farmacologia , Raios gama , Camundongos , Camundongos Endogâmicos , Extratos Vegetais/farmacologia , Protetores contra Radiação/farmacologia , Sementes
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