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1.
Heliyon ; 10(7): e28792, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586407

RESUMO

Background: Physical activity (PA) is widely recommended for preventing and combating obesity, but the most effective PA pattern for treating obesity remains unclear. Cardiometabolic index (CMI), derived from waist height ratio and triglycerides to high-density lipoprotein-cholesterol ratio, is a novel indicator for evaluating obesity. However, the relationship between different PA patterns and CMI remains unelucidated. Objective: This study aimed to explore the association between different PA patterns and CMI in U.S. adults. Methods: Participants with complete information in CMI, PA patterns, and other covariates in the National Health and Nutrition Examination Survey database (2007-2016) were included in this study. Multivariate linear regression models were utilized to explore the relationship between PA patterns and CMI. Moreover, stratified analyses, interaction tests and restricted cubic spline (RCS) regression analysis were used to investigate the stability and nonlinearity of the association, respectively. Results: A total of 16,442 adults were included in this study. After adjusting for all potential covariates, only the regularly active group was significantly associated with CMI reduction (ß = -0.13, 95% CI: 0.19 to -0.07, P < 0.0001), while the weekend warriors group did not achieve equivalent CMI reduction (ß = -0.09, 95% CI: 0.32 to 0.14, P = 0.4204). Subgroup analyses and interaction tests revealed that the CMI-PA association was more pronounced in the subgroup with age≤45 or >60, with higher education level, and who are current drinkers. Furthermore, RCS analysis indicated that total PA in a week was significantly, nonlinearly associated with CMI in non-inactive adults, and that a total of PA more than 330 min can reap favorable CMI reduction. Conclusion: Being regularly active is associated with significant CMI reduction, while being weekend warriors and insufficiently active do not achieve equivalent benefits. For non-inactive individuals, engaging in PA for more than 330 min weekly helps to reduce CMI effectively.

2.
ACS Biomater Sci Eng ; 9(10): 5737-5746, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37733924

RESUMO

Inflammatory bowel disease (IBD) is a frequently occurring disease that seriously influences the patient's quality of life. To decrease adverse effects and improve efficacy of therapeutics, nanomedicines have been widely used to treat IBD. However, how to thoroughly release payloads under an inflammatory microenvironment and synergistic therapy of IBD need to be further investigated. To address this issue, cyclosporine A (CsA)-loaded, folic acid (FA)-modified, pH and reactive oxygen species (ROS) dual-responsive nanoparticles (FA-CsA NPs) were fabricated using pH/ROS-responsive material as carrier. The prepared FA-CsA NPs had spherical shape and uniform size distribution and could smartly release their payloads under acid and/or ROS microenvironment. In vitro experiments demonstrated that FA-CsA NPs can be effectively internalized by activated macrophages, and the internalized NPs could down-regulate the expression of proinflammatory cytokines compared to free drug or nontargeted NPs. In vivo experiments verified that FA-CsA NPs significantly accumulated at inflammatory colon tissues and the accumulated NPs obviously improved the symptoms of colitis in mice without obvious adverse effects. In conclusion, our results provided a candidate for the targeted treatment of IBD.

3.
Biochim Biophys Acta Mol Basis Dis ; 1869(7): 166795, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37385514

RESUMO

The senescence of bone marrow mesenchymal stem cells (BMSCs) is the basis of senile osteoporosis (SOP). Targeting BMSCs senescence is of paramount importance for developing anti-osteoporotic strategy. In this study, we found that protein tyrosine phosphatase 1B (PTP1B), an enzyme responsible for tyrosine dephosphorylation, was significantly upregulated in BMSCs and femurs with advancing chronological age. Therefore, the potential role of PTP1B in BMSCs senescence and senile osteoporosis was studied. Firstly, significantly upregulated PTP1B expression along with impaired osteogenic differentiation capacity was observed in D-galactose (D-gal)-induced BMSCs and naturally-aged BMSCs. Furthermore, PTP1B silencing could effectively alleviate senescence, improve mitochondrial dysfunction, and restore osteogenic differentiation in aged BMSCs, which was attributable to enhanced mitophagy mediated by PKM2/AMPK pathway. In addition, hydroxychloroquine (HCQ), an autophagy inhibitor, significantly reversed the protective effects from PTP1B knockdown. In SOP animal model, transplantation of LVsh-PTP1B-transfected D-gal-induced BMSCs harvested double protective effects, including increased bone formation and reduced osteoclastogenesis. Similarly, HCQ treatment remarkably suppressed osteogenesis of LVsh-PTP1B-transfected D-gal-induced BMSCs in vivo. Taken together, our data demonstrated that PTP1B silencing protects against BMSCs senescence and mitigates SOP via activating AMPK-mediated mitophagy. Targeting PTP1B may represent a promising interventional strategy to attenuate SOP.


Assuntos
Células-Tronco Mesenquimais , Osteoporose , Animais , Osteogênese , Proteínas Quinases Ativadas por AMP/metabolismo , Mitofagia , Monoéster Fosfórico Hidrolases/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteoporose/genética , Osteoporose/metabolismo
4.
Acta Biomater ; 164: 458-473, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37072065

RESUMO

Rheumatoid arthritis (RA) is an autoimmune disease causing severe symptoms that are difficult to treat. Nano-drug delivery system is recognized as a promising strategy for management of RA. However, how to thoroughly release payloads from nanoformulations and synergistic therapy of RA needs to be further investigated. To address this issue, a pH and reactive oxygen species (ROS) dual-responsive, methylprednisolone (MPS)-loaded and arginine-glycine-aspartic acid (RGD)-modified nanoparticles (NPs) was fabricated using phytochemical and ROS-responsive moiety co-modified α-cyclodextrin (α-CD) as a carrier. In vitro and in vivo experiments verified that the pH/ROS dual-responsive nanomedicine could be efficiently internalized by activated macrophages and synovial cells, and the released MPS could promote transformation of M1-type macrophages into M2 phenotype, thereby down-regulating pro-inflammatory cytokines. In vivo experiments demonstrated that the pH/ROS dual-responsive nanomedicine was remarkably accumulated in the inflamed joints of mice with collagen-induced arthritis (CIA). The accumulated nanomedicine could obviously relieve joint swelling and cartilage destruction without obvious adverse effects. Importantly, the expression of interleukin-6 and tumor necrosis factor-α in the joints of CIA mice were significantly inhibited by the pH/ROS dual-responsive nanomedicine in comparison with free drug and non-targeted counterparts. In addition, the expression of the NF-κB signaling pathway molecule P65 was also significantly decreased by nanomedicine-treatment. Our results reveal that MPS-loaded pH/ROS dual-responsive NPs can effectively alleviate joint destruction via down-regulation of the NF-κB signaling pathway. STATEMENT OF SIGNIFICANCE: Nanomedicine is recognized as an attractive method for the targeting treatment of rheumatoid arthritis (RA). To thorough release of payloads from nanoformulations and synergistic therapy of RA, herein, a phytochemical and ROS-responsive moiety co-modified α-cyclodextrin was used as a pH/ROS dual-responsive carrier to encapsulate methylprednisolone to manage RA. The fabricated nanomedicine can effectively release its payloads under pH and/or ROS microenvironment, and the released drugs dramatically promote transformation of M1-type macrophages into M2 phenotype to reduce the release of pro-inflammatory cytokines. The prepared nanomedicine also obviously decreased the NF-κB signaling pathway molecule P65 expression in the joints, thereby down-regulating pro-inflammatory cytokines expression to alleviate joint swelling and cartilage destruction. We provided a candidate for the targeting treatment of RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Nanopartículas , alfa-Ciclodextrinas , Camundongos , Animais , NF-kappa B/metabolismo , Glucocorticoides/farmacologia , Espécies Reativas de Oxigênio , alfa-Ciclodextrinas/farmacologia , alfa-Ciclodextrinas/uso terapêutico , Transdução de Sinais , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Citocinas/farmacologia , Nanopartículas/uso terapêutico , Nanopartículas/química , Metilprednisolona , Concentração de Íons de Hidrogênio
5.
Front Psychol ; 13: 897031, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248544

RESUMO

Reference in extended discourse is vulnerable to delayed acquisition in early childhood. Although recent research has increasingly focused on effects of linguistic, input, and cognitive factors on reference production, these studies are limited in number and the results are mixed. The present study provides insight into bilingual reference production by investigating how production of referring expressions in the two languages of preschool bilingual children may be influenced by structural similarities and differences between the languages, frequency of referring expressions in maternal input, amount of exposure to each of the languages, and working memory capacity. Using two stories in the Multilingual Assessment Instrument for Narratives (MAIN), we examined character introduction and re-introduction in oral narratives of 4-6-year-old Singaporean bilingual children acquiring Mandarin Chinese and English (n = 21), and in child-directed speech of the mothers (n = 17). The children's language exposure, executive function, and general bilingual proficiency were also recorded or directly tested through structured interviews with the parents or standardized assessments with the children. Data collection was conducted remotely in real time over a video-conferencing platform, supplemented by on-site audio recording to ensure sound quality. Results showed prolonged development in the production of felicitous REs for first mentions and over-reliance on overt marking of definiteness in our bilingual children. Mixed modeling revealed that frequency of felicitous REs in the input predicted children's production of felicitous REs across languages and discourse functions, with a modulating effect of working memory. Overall, our findings are consistent with previous ones in that reference production is vulnerable in early Mandarin-English bilinguals in a multilingual society. This study also presents novel evidence that structural frequency in the input interacts with working memory in shaping patterns of reference production in bilingual children.

6.
Stem Cells Int ; 2022: 2401693, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36193255

RESUMO

Homing of mesenchymal stem cells (MSCs) to the defect site is indispensable for bone repair. Local endothelial cells (ECs) can recruit MSCs; however, the mechanism remains unclear, especially in the context of the inflammatory microenvironment. This study was aimed to investigate the role of ECs in MSCs migration during the inflammatory phase of bone repair. The inflammatory microenvironment was mimicked in vitro via adding a cytokine set (IL-1ß, IL-6, and TNF-α) to the culture medium of ECs. The production of PDGF-BB from ECs was measured by ELISA. Transwell and wound healing assays were employed to assess MSCs migration toward ECs and evaluate the implication of PDGF-BB/PDGFRß. A series of shRNA and pathway inhibitors were used to screen signal molecules downstream of PDGF-BB/PDGFRß. Then, mouse models of femoral defects were fabricated and DBM scaffolds were implanted. GFP+ MSCs were injected via tail vein, and the relevance of PDGF-BB/PDGFRß, as well as screened signal molecules, in cell homing was further verified during the early phase of bone repair. In the mimicked inflammatory microenvironment, MSCs migration toward ECs was significantly promoted, which could be abrogated by pdgfrb knockout in MSCs. Inhibition of Src or Akt led to negative effects analogous to pdgfrb knockout. Blockade of JNK, MEK, and p38 MAPK had no impact. Meanwhile, the secretion of PDGF-BB from ECs was evidently motivated by the inflammatory microenvironment. Adding recombinant PDGF-BB protein to the culture medium of ECs phenocopied the inflammatory microenvironment with regard to attracting MSCs, which was abolished by pdgfb, src, or akt in MSCs. Moreover, pdgfb knockout suppressed the expression and phosphorylation of Src and Akt in migrating MSCs. Src knockout impaired Akt expression but not vice versa. In vivo, reduced infiltration of CD31+ ECs was correlated with diminished PDGF-BB in local defect sites, and silencing pdgfb, src, or akt in MSCs markedly hampered cell homing. Together, these findings suggest that in the inflammatory microenvironment, MSCs migrate toward ECs via PDGF-BB/PDGFRß and the downstream Src-Akt signal pathway.

7.
Acta Biomater ; 143: 471-486, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35259516

RESUMO

Chronic bacterial prostatitis (CBP) occurs frequently in the male population and significantly influences quality of life. Antibiotics are the main strategy for managing chronic bacterial prostatitis; however, most antibiotics have low efficacy due to their poor penetration of prostate tissues. To overcome this challenge, we fabricated cefpodoxime proxetil (CPD)-loaded reactive oxygen species (ROS)-responsive nanoparticles (NPs) for targeted treatment of CBP. These NPs were modified with folic acid (FA) and could be effectively internalized by bacteria-infected macrophages and prostatic epithelial cells because of the high expression of folate receptors (FRs) in these cells. In vitro cellular assays demonstrated that the CPD-loaded nanomedicine can obviously reduce proinflammatory cytokine expression in cells since the nanomedicine can efficiently eradicate cellular bacteria. In vivo imaging results verified that FA-modified nanomedicines can penetrate the prostatic epithelium and accumulate in the glandular lumen because FRs overexpression was also observed in the prostate tissues of CBP mice. Animal experiments demonstrated that FA-modified nanomedicine can remarkably relieve pelvic pain in CBP mice and dramatically decrease proinflammatory cytokine expression in prostate tissues via eradication of bacteria and scavenging of ROS. Our results provide a new strategy to deliver antibiotics for targeted therapy of CBP. STATEMENT OF SIGNIFICANCE: To overcome poor penetration of antibiotics in prostatic tissues, we developed an antibiotics-loaded ROS-responsive NPs for targeted treatment of CBP. We demonstrated that both bacteria-infected macrophages and prostatic epithelial cells have FRs overexpression, thus FA-modified NPs can be efficiently internalized by these cells. FA-modified NPs can penetrate the prostatic epithelium and accumulate in the glandular lumen via FRs-mediated endocytosis, and the accumulated NPs can smartly release their payload under high ROS microenvironment. A distinguished therapy outcome was obtained in murine CBP model since CPD-loaded NPs can efficiently eradicate the resident bacteria in prostate tissues and downregulate proinflammatory cytokine expression. Our work provides a practicable strategy to expand the application of antibiotics for management of CBP.


Assuntos
Nanopartículas , Prostatite , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Citocinas , Ácido Fólico , Humanos , Masculino , Camundongos , Nanomedicina , Nanopartículas/uso terapêutico , Prostatite/tratamento farmacológico , Prostatite/microbiologia , Qualidade de Vida , Espécies Reativas de Oxigênio/metabolismo
9.
Cell Transplant ; 29: 963689720940722, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32731815

RESUMO

The treatment of bone defects has always been a challenge for orthopedic surgeons. The development of tissue engineering technology provides a novel method for repairing bone defects and has been used in animal experiments and clinical trials. However, there are few clinical studies on comparing the long-term outcomes of tissue-engineered bones (TEBs) and other bone grafts in treating bone defects, and the long-term efficiency of TEBs remains controversial. Therefore, a study designed by us was aimed to compare the long-term efficacy and safety of individual tissue-engineered bones (iTEBs) and allogeneic bone granules (ABGs) in treating bone defects caused by curettage of benign bone tumors and tumor-like lesions. From September 2003 to November 2009, 48 patients who received tumor curettage and bone grafting were analyzed with a mean follow-up of 122 mo (range 60 to 173 mo). Based on implant style, patients were divided into groups of iTEBs (n = 23) and ABGs (n = 25). Postoperatively, the healing time, healing quality, incidence of complications, and functional scores were compared between the two groups. The Musculoskeletal Tumor Society functional evaluation system and Activities of Daily Living Scale scores were significantly improved in both groups with no significant difference. The average healing time of ABGs was longer than that of iTEBs (P < 0.05). At the final follow-up, iTEBs had a better performance in the bone healing quality evaluated by modified Neer classification (P < 0.05). In the group of iTEBs, the complication and reoperation rate was lower than that in the group of ABGs, with no tumorigenesis or immune rejection observed. In summary, for treating bone defects caused by tumor curettage, iTEBs were safe, effective, and tagged with more rapid healing speed, better healing outcome, and lower complication and reoperation rate, in comparison with ABGs.


Assuntos
Doenças Ósseas/terapia , Transplante Ósseo/métodos , Osso e Ossos/citologia , Engenharia Tecidual/métodos , Adolescente , Adulto , Doenças Ósseas/patologia , Neoplasias Ósseas/patologia , Neoplasias Ósseas/terapia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Transplante Homólogo , Adulto Jovem
10.
Adv Healthc Mater ; 9(13): e2000353, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32424991

RESUMO

The immunologic response toward chronic inflammation or bone regeneration via the accumulation of M1 or M2 macrophages after injury could determine the fate of biomaterial. Human umbilical cord mesenchymal stem cells (hUCMSCs) have a pivotal immunomodulatory property on directing macrophage behaviors. Herein, for the first time, 3D-printed poly(lactide-co-glycolide) (PLGA) scaffolds modified with hUCMSC-derived extracellular matrix (PLGA-ECM) are prepared by a facile tissue engineering technique with physical decellularization and 2.44 ± 0.29 mg cm-3 proteins immobilized on the PLGA-ECM contain multiple soluble cytokines with a sustainable release profile. The PLGA-ECM not only attenuates the foreign body response, but also improves bone regeneration by increasing the accumulation of M2 macrophages in an improved heterotopic transplantation model of SCID mice. Furthermore, the PLGA-ECM scaffolds with the knockdown of transforming growth factor-ß-induced protein (TGFßI/ßig-H3) demonstrate that M2 macrophage accumulation improved by the PLGA-ECM could be attributed to increasing the migration of M2 macrophages and the repolarization of M1 macrophages to M2 phenotype, which are mediated by multiple integrin signaling pathways involving in integrin ß7, integrin α9, and integrin ß1 in a TGFßI-dependent manner. This study presents an effective surface modification strategy of polymeric scaffolds to initiate tissue regeneration and combat inflammatory response by increasing M2 macrophage accumulation.


Assuntos
Matriz Extracelular , Alicerces Teciduais , Animais , Regeneração Óssea , Inflamação , Macrófagos , Camundongos , Camundongos SCID , Fator de Crescimento Transformador beta
11.
Nanotechnology ; 28(29): 295601, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28557808

RESUMO

The development of environmentally responsive drug delivery systems for the treatment of cancer has attracted particular interest in recent years. However, the enhancement of drug loading capacity and realization of pH-responsive drug delivery remain challenging. Herein, we employ carboxymethyl curdlan as a hydrophilic carrier to wrap doxorubicin (DOX) directly via electrostatic interaction. The sizes of the formed nanoparticles can be simply tuned by changing their feeding ratios. In particular, the nanoparticles are highly stable in aqueous solution without size variation. In vitro drug release and cytotoxicity assays illustrate that this delivery system can release DOX differentially under various environmental conditions and transport it into cell nuclei efficiently, with comparable therapeutic effect to the free drug. These results suggest that the carrying of antitumor drugs by polysaccharide via electrostatic interaction is a simple but effective way to construct a pH-dependent drug delivery platform.


Assuntos
Doxorrubicina , Neoplasias/tratamento farmacológico , beta-Glucanas , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Neoplasias/metabolismo , Neoplasias/patologia , Eletricidade Estática , beta-Glucanas/química , beta-Glucanas/farmacologia
12.
Nanotechnology ; 25(25): 255101, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-24896540

RESUMO

Doxorubicin (DOX), one of the most widely used anticancer drugs, is restricted in clinical application due to its severe side effects and inefficient cellular uptake. To overcome the drawbacks, herein, an endosomal pH-activated prodrug was designed and fabricated by conjugating DOX with chitosan via an acid-cleavable hydrazone bond. The resulting DOX conjugates can self-assemble into nano-sized particles, which were very stable and presented no burst release of DOX at a neutral pH condition. Notably, the nanoparticles exhibited excellent cell uptake properties and a remarkable drug accumulation in tumor cells. Once internalized into the cells, moreover, DOX can be fast released from the nanoparticles, and the release mechanism changed from the anomalous transport at pH 7.4 to the combination pattern of diffusion- and erosion-controlled release at pH 6.0 or 5.0. The prodrugs showed obvious cytotoxicity for HeLa cells with fairly low IC50 values, offering a new platform for targeted cancer therapy.


Assuntos
Antineoplásicos/química , Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Pró-Fármacos/química , Antineoplásicos/farmacologia , Quitosana/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Células HeLa , Humanos , Hidrazonas/química , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Nanopartículas/química , Pró-Fármacos/farmacologia
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