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1.
Biomacromolecules ; 25(2): 964-974, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38232296

RESUMO

Thermosensitive nanoparticles can be activated by externally applying heat, either through laser irradiation or magnetic fields, to trigger the release of drug payloads. This controlled release mechanism ensures that drugs are specifically released at the tumor site, maximizing their effectiveness while minimizing systemic toxicity and adverse effects. However, its efficacy is limited by the low concentration of drugs at action sites, which is caused by no specific target to tumor sties. Herein, hyaluronic acid (HA), a gooey, slippery substance with CD44-targeting ability, was conjugated with a thermosensitive polymer poly(acrylamide-co-acrylonitrile) to produce tumor-targeting and thermosensitive polymeric nanocarrier (HA-P) with an upper critical solution temperature (UCST) at 45 °C, which further coloaded chemo-drug doxorubicin (DOX) and photosensitizer Indocyanine green (ICG) to prepare thermosensitive nanoreactors HA-P/DOX&ICG. With photosensitizer ICG acting as the "temperature control element", HA-P/DOX&ICG nanoparticles can respond to temperature changes when receiving near-infrared irradiation and realize subsequent structure depolymerization for burst drug release when the ambient temperature was above 45 °C, achieving programmable and on-demand drug release for effective antitumor therapy. Tumor inhibition rate increased from 61.8 to 95.9% after laser irradiation. Furthermore, the prepared HA-P/DOX&ICG nanoparticles possess imaging properties, with ICG acting as a probe, enabling real-time monitoring of drug distribution and therapeutic response, facilitating precise treatment evaluation. These results provide enlightenment for the design of active tumor targeting and NIR-triggered programmable and on-demand drug release of thermosensitive nanoreactors for tumor therapy.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Humanos , Fármacos Fotossensibilizantes/uso terapêutico , Hipertermia Induzida/métodos , Fototerapia/métodos , Doxorrubicina/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Verde de Indocianina/farmacologia , Verde de Indocianina/química , Nanotecnologia , Liberação Controlada de Fármacos , Linhagem Celular Tumoral
2.
Anim Nutr ; 16: 23-33, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38131030

RESUMO

This study aimed to determine the regulatory mechanism of dietary zinc lactate (ZL) supplementation on intestinal oxidative stress damage in a paraquat (PQ)-induced piglet model. Twenty-eight piglets (mean body weight 9.51 ± 0.23 kg) weaned at 28 d of age were randomly divided into control, ZL, PQ, and ZL + PQ groups (n = 7 in each group). The ZL-supplemented diet had little effect on growth performance under normal physiological conditions. However, under PQ challenge, ZL supplementation significantly improved average daily gain (P < 0.05) and reduced the frequency of diarrhea. ZL improved intestinal morphology and ultrastructure by significantly increasing the expression level of the jejunal tight junction protein, zonula occludens-1 (ZO-1) (P < 0.05), and intestinal zinc transport and absorption in PQ-induced piglets, which reduced intestinal permeability. ZL supplementation also enhanced the expression of antioxidant and anti-inflammatory factor-related genes and decreased inflammatory cytokine expression and secretion in PQ-induced piglets. Furthermore, ZL treatment significantly inhibited the activation of constitutive androstane receptor (CAR) signaling (P < 0.01) in PQ-induced piglets and altered the structure of the gut microbiota, especially by significantly increasing the abundance of beneficial gut microbes, including UCG_002, Ruminococcus, Rikenellaceae_RC9_gut_group, Christensenellaceae_R_7_group, Treponema, unclassified_Christensenellaceae, and unclassified_Erysipelotrichaceae (P < 0.05). These data reveal that pre-administration of ZL to piglets can suppress intestinal oxidative stress by improving antioxidant and anti-inflammatory capacity and regulating the crosstalk between CAR signaling and gut microbiota.

3.
Nutrients ; 15(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36615853

RESUMO

Endogenous glutathione (GSH) effectively regulates redox homeostasis in the body. This study aimed to investigate the regulatory mechanism of different dietary levels of GSH supplementation on the intestinal barrier and antioxidant function in a paraquat-induced stress-weaned piglet model. Our results showed that dietary 0.06% GSH supplementation improved the growth performance of weaned piglets under normal and stressful conditions to some degree and decreased the diarrhea rate throughout. Exogenous GSH improved paraquat-induced changes in intestinal morphology, organelle, and permeability and reduced intestinal epithelial cell apoptosis. Moreover, GSH treatment alleviated intestinal oxidative stress damage by upregulating antioxidant (GPX4, CnZnSOD, GCLC, and GCLM) and anti-inflammatory (IL-10) gene expression and downregulating inflammatory cytokines (IFN-γ and IL-12) gene expression. Furthermore, GSH significantly reduced the expression levels of constitutive androstane receptor (CAR), RXRα, HSP90, PP2Ac, CYP2B22, and CYP3A29, and increased the expression levels of GSTA1 and GSTA2 in the jejunum and ileum of paraquat-induced piglets. We conclude that exogenous GSH protects against oxidative stress damage by regulating the intestinal barrier, antioxidant capacity, and CAR signaling pathway.


Assuntos
Antioxidantes , Paraquat , Animais , Suínos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Paraquat/toxicidade , Suplementos Nutricionais , Receptor Constitutivo de Androstano , Glutationa/metabolismo , Estresse Oxidativo , Transdução de Sinais , Desmame
4.
J Control Release ; 329: 121-135, 2021 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-33279604

RESUMO

Calcium supplement is the most commonly adopted treatment for osteoporosis but usually requires high dose and frequency. The modality of calcium supplement is therefore overlooked by current nanomedicine-based osteoporosis therapies without proper oral formulations. Herein, we proposed a tetracycline (Tc) modified and monostearin (MS) coated amorphous calcium carbonate (ACC) platform (TMA) as oral bone targeted and osteoporosis microenvironment (water/pH) responsive carrier for in situ calcium supplement. Moreover, current osteoporosis therapies also fall short of finding suitable molecular target and effective therapeutic regimen to further increase the therapeutic efficacy over available treatment means. As a result, the simvastatin (Sim) was loaded into TMA to construct drug delivery system (TMA/Sim) capable of synergistically activating the bone morphogenetic proteins (BMPs)-Smad pathway to provide a novel therapeutic regimen for osteoblast promotion mediated osteoporosis therapy. Our results revealed that optimized TMA showed high accessibility and oral availability with targeted drug delivery to bone tissue. Most importantly, benefit from the effective in situ calcium supplement and targeted Sim delivery, this therapeutic regime (TMA/Sim) achieved better synergetic effects than conventional combination strategies with promising osteoporosis reversion performance under low calcium dosage (1/10 of commercial calcium carbonate tablet) and significantly attenuated side effects.


Assuntos
Osteoporose , Sinvastatina , Cálcio , Humanos , Concentração de Íons de Hidrogênio , Osteoblastos , Água
5.
Theranostics ; 10(19): 8591-8605, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754265

RESUMO

Background: The calcium supplement is a clinically approved approach for osteoporosis therapy but usually requires a large dosage without targetability and with poor outcome. This modality is not fully explored in current osteoporosis therapy due to the lack of proper calcium supplement carrier. Methods: In this study, we constructed a tetracycline (Tc) modified and simvastatin (Sim) loaded phospholipid-amorphous calcium carbonate (ACC) hybrid nanoparticle (Tc/ACC/Sim). Results: The resulted Tc/ACC/Sim was able to enhance its accumulation at the osteoporosis site. Most importantly, the combination of calcium supplement and Sim offered synergetic osteoblast promotion therapy of osteoporosis with advanced performance than non-targeted system or mono therapy. Conclusion: This platform provides an alternative approach to stimulate bone formation by synergetic promotion of osteoblast differentiation using calcium supplement and Sim.


Assuntos
Carbonato de Cálcio/administração & dosagem , Osteoblastos/citologia , Osteoporose/tratamento farmacológico , Sinvastatina/administração & dosagem , Tetraciclina/administração & dosagem , Animais , Carbonato de Cálcio/química , Carbonato de Cálcio/farmacologia , Diferenciação Celular , Linhagem Celular , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Sinergismo Farmacológico , Feminino , Humanos , Camundongos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoporose/metabolismo , Ratos , Sinvastatina/química , Sinvastatina/farmacologia , Tetraciclina/química , Tetraciclina/farmacologia
6.
Front Neurol ; 11: 502, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582014

RESUMO

Parkinson's disease (PD) is a chronic neurodegenerative disease with complex motor and non-motor symptoms often leading to significant caregiver burden. An integrated, multidisciplinary care setup involving different healthcare professionals is the mainstay in the holistic management of PD. Many challenges in delivering multidisciplinary team (MDT) care exist, such as insufficient expertise among different healthcare professionals, poor interdisciplinary collaboration, and communication. The need to attend different clinics, incurring additional traveling and waiting time for allied health therapies can also make MDT care more burdensome. By shifting MDT care to local community settings and into patients' homes, patient-centered care can be achieved. In Singapore, the National Neuroscience Institute created the Community Care Partners Programme in 2007 to bring the allied MDT team to the community and nurse-led Integrated Community Care Programme for Parkinson's Disease in 2012 to provide care in community and at patient's home. However, attaining MDT care in the community setting is difficult to achieve where there is a shortage of PD-trained professionals. As such, interdisciplinary and transdisciplinary management would be other best practice options to deliver patient-centric care in PD. Telemedicine could be another viable option to bring the MDT closer to the patient.

7.
Nat Plants ; 6(4): 360-367, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32231254

RESUMO

Temperature-sensitive genic male sterility (TGMS) lines are widely used in the breeding of hybrid crops1,2, but by what means temperature as a general environmental factor reverses the fertility of different TGMS lines remains unknown. Here, we identified an Arabidopsis TGMS line named reversible male sterile (rvms) that is fertile at low temperature (17 °C) and encodes a GDSL lipase. Cytological observations and statistical analysis showed that low temperature slows pollen development. Further screening of restorers of rvms, as well as crossing with a slow-growth line at normal temperature (24 °C), demonstrate that slowing of development overcomes the defects of rvms microspores and allows them to develop into functional pollen. Several other Arabidopsis TGMS lines were identified, and their fertility was also restored by slowing of development. Given that male reproductive development is conserved3, we propose that slowing of development is a general mechanism applicable to the sterility-fertility conversion of TGMS lines from different plant species.


Assuntos
Arabidopsis/fisiologia , Termotolerância , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/ultraestrutura , Temperatura Baixa , Fertilidade/genética , Perfilação da Expressão Gênica , Interação Gene-Ambiente , Genes de Plantas , Mutação , Desenvolvimento Vegetal/genética , Desenvolvimento Vegetal/fisiologia , Pólen/genética , Pólen/crescimento & desenvolvimento , Termotolerância/genética
8.
Plant Physiol ; 178(1): 283-294, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30018171

RESUMO

Sporopollenin is the major component of the outer pollen wall (sexine). It is synthesized using a pathway of approximately eight genes in Arabidopsis (Arabidopsis thaliana). MALE STERILITY188 (MS188) and its direct upstream regulator ABORTED MICROSPORES (AMS) are two transcription factors essential for tapetum development. Here, we show that all the sporopollenin biosynthesis proteins are specifically expressed in the tapetum and are secreted into anther locules. MS188, a MYB transcription factor expressed in the tapetum, directly regulates the expression of POLYKETIDE SYNTHASE A (PKSA), PKSB, MALE STERILE2 (MS2), and a CYTOCHROME P450 gene (CYP703A2). By contrast, the expression of CYP704B1, ACYL-COA SYNTHETASE5 (ACOS5), TETRAKETIDE a-PYRONE REDUCTASE1 (TKPR1) and TKPR2 are significantly reduced in ams mutants but not affected in ms188 mutants. However, MS188 but not AMS can activate the expression of CYP704B1, ACOS5, and TKPR1 In ms188, dominant suppression of MS188 homologs reduced the expression of these genes, suggesting that MS188 and other MYB family members play redundant roles in activating their expression. The expression of some sporopollenin synthesis genes (PKSA, PKSB, TKPR2, CYP704B1, and ACOS5) was rescued when MS188 was expressed in ams Therefore, MS188 is a key regulator for activation of sporopollenin synthesis, and AMS and MS188 may form a feed-forward loop that activates the expression of the sporopollenin biosynthesis pathway for rapid pollen wall formation.


Assuntos
Biopolímeros/biossíntese , Carotenoides/biossíntese , Parede Celular/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Pólen/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Microscopia Confocal , Mutação , Plantas Geneticamente Modificadas , Pólen/citologia , Pólen/metabolismo , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Oxid Med Cell Longev ; 2015: 125106, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26161234

RESUMO

Objective. Ischemia/reperfusion (I/R) injury is an unavoidable event for patients in cardiac surgery under cardiopulmonary bypass (CPB). This study was designed to investigate whether glutaraldehyde-polymerized human placenta hemoglobin (PolyPHb), a hemoglobin-based oxygen carrier (HBOC), can protect heart against CPB-induced I/R injury or not and to elucidate the underlying mechanism. Methods and Results. A standard dog CPB model with 2-hour cardiac arrest and 2-hour reperfusion was established. The results demonstrated that a low-dose PolyPHb (0.1%, w/v) provided a significant protection on the I/R heart, whereas the high-dose PolyPHb (3%, w/v) did not exhibit cardioprotective effect, as evidenced by the impaired cardiac function, decreased myocardial oxygen utilization, and elevated enzymes release and pathological changes. Further study indicated that exposure of isolated coronary arteries or human umbilical vein endothelial cells (HUVECs) to a high-dose PolyPHb caused impaired endothelium-dependent relaxation, which was companied with increased reactive oxygen species (ROS) production, reduced superoxide dismutase (SOD) activity, and elevated malonaldehyde (MDA) formation. Consistent with the increased oxidative stress, the NAD(P)H oxidase activity and subunits expression, including gp91(phox), p47(phox), p67(phox), and Nox1, were greatly upregulated. Conclusion. The high-dose PolyPHb fails to protect heart from CPB-induced I/R injury, which was due to overproduction of NAD(P)H oxidase-induced ROS and resultant endothelial dysfunction.


Assuntos
Substitutos Sanguíneos/farmacologia , Vasos Coronários/metabolismo , Hemoglobinas/química , Estresse Oxidativo/efeitos dos fármacos , Animais , Substitutos Sanguíneos/química , Substitutos Sanguíneos/uso terapêutico , Ponte Cardiopulmonar , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/patologia , Creatina Quinase Forma MB/metabolismo , Modelos Animais de Doenças , Cães , Feminino , Glutaral/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Malondialdeído/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/etiologia , Miocárdio/metabolismo , NADPH Oxidases/metabolismo , Placenta/metabolismo , Gravidez , Subunidades Proteicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
Artif Cells Nanomed Biotechnol ; 41(5): 289-92, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23363417

RESUMO

OBJECTIVES: To reduce the mean molecular weight [Formula: see text] and to increase the effective polymerization ratio (REff) of polymerized human placenta hemoglobin (PolyPHb). METHODS: Three factors of GDA-PolyPHb process such as the approach of feeding GDA (FGDA), hemoglobin concentration ([Hb]) and the molar ratio of GDA, and hemoglobin(RGDA:Hb) were investigated. Finally, the expansion experiments were conducted with optimal conditions. RESULTS: The data showed that the HBOCs with the REff of 67.35% and lower [Formula: see text] of 162.70 kDa were prepared by optimal conditions. CONCLUSION: Compared to original process, the optimal process greatly decreased the [Formula: see text] and increased the REff.


Assuntos
Transfusão de Sangue , Terapias Complementares , Glutaral/química , Hemoglobinas/química , Polimerização , Sistema Livre de Células , Feminino , Hemoglobinas/metabolismo , Humanos , Peso Molecular , Placenta/metabolismo , Gravidez
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