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1.
Int J Mol Sci ; 25(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38791352

RESUMO

Biofunctionalized hydrogels are widely used in tissue engineering for bone repair. This study examines the bone regenerative effect of the blood-derived growth factor preparation of Hypoxia Preconditioned Serum (HPS) and its fibrin-hydrogel formulation (HPS-F) on drilled defects in embryonic day 19 chick femurs. Measurements of bone-related growth factors in HPS reveal significant elevations of Osteopontin, Osteoprotegerin, and soluble-RANKL compared with normal serum (NS) but no detection of BMP-2/7 or Osteocalcin. Growth factor releases from HPS-F are measurable for at least 7 days. Culturing drilled femurs organotypically on a liquid/gas interface with HPS media supplementation for 10 days demonstrates a 34.6% increase in bone volume and a 52.02% increase in bone mineral density (BMD) within the defect area, which are significantly higher than NS and a basal-media-control, as determined by microcomputed tomography. HPS-F-injected femur defects implanted on a chorioallantoic membrane (CAM) for 7 days exhibit an increase in bone mass of 123.5% and an increase in BMD of 215.2%, which are significantly higher than normal-serum-fibrin (NS-F) and no treatment. Histology reveals calcification, proteoglycan, and collagen fiber deposition in the defect area of HPS-F-treated femurs. Therefore, HPS-F may offer a promising and accessible therapeutic approach to accelerating bone regeneration by a single injection into the bone defect site.


Assuntos
Regeneração Óssea , Fêmur , Fibrina , Animais , Regeneração Óssea/efeitos dos fármacos , Fêmur/efeitos dos fármacos , Fêmur/diagnóstico por imagem , Fêmur/metabolismo , Fibrina/metabolismo , Embrião de Galinha , Densidade Óssea/efeitos dos fármacos , Hidrogéis , Microtomografia por Raio-X , Engenharia Tecidual/métodos , Soro/metabolismo , Soro/química
2.
Plant Cell Rep ; 42(11): 1825-1832, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37750948

RESUMO

KEY MESSAGE: A new genomic prediction method (RHPP) was developed via combining randomized Haseman-Elston regression (RHE-reg), PCR based on genomic information of core population, and preconditioned conjugate gradient (PCG) algorithm. Computational efficiency is becoming a hot issue in the practical application of genomic prediction due to the large number of data generated by the high-throughput genotyping technology. In this study, we developed a fast genomic prediction method RHPP via combining randomized Haseman-Elston regression (RHE-reg), PCR based on genomic information of core population, and preconditioned conjugate gradient (PCG) algorithm. The simulation results demonstrated similar prediction accuracy between RHPP and GBLUP, and significantly higher computational efficiency of the former with the increase of individuals. The results of real datasets of both bread wheat and loblolly pine demonstrated that RHPP had a similar or better predictive accuracy in most cases compared with GBLUP. In the future, RHPP may be an attractive choice for analyzing large-scale and high-dimensional data.

3.
Int J Mol Sci ; 24(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36982558

RESUMO

Hypoxia Preconditioned Plasma (HPP) and Serum (HPS) are regenerative blood-derived growth factor compositions that have been extensively examined for their angiogenic and lymphangiogenic activity towards wound healing and tissue repair. Optimization of these secretomes' growth factor profile, through adjustments of the conditioning parameters, is a key step towards clinical application. In this study, the autologous liquid components (plasma/serum) of HPP and HPS were replaced with various conditioning media (NaCl, PBS, Glucose 5%, AIM V medium) and were analyzed in terms of key pro- (VEGF-A, EGF) and anti-angiogenic (TSP-1, PF-4) protein factors, as well as their ability to promote microvessel formation in vitro. We found that media substitution resulted in changes in the concentration of the aforementioned growth factors, and also influenced their ability to induce angiogenesis. While NaCl and PBS led to a lower concentration of all growth factors examined, and consequently an inferior tube formation response, replacement with Glucose 5% resulted in increased growth factor concentrations in anticoagulated blood-derived secretomes, likely due to stimulation of platelet factor release. Medium substitution with Glucose 5% and specialized peripheral blood cell-culture AIM V medium generated comparable tube formation to HPP and HPS controls. Altogether, our data suggest that medium replacement of plasma and serum may significantly influence the growth factor profile of hypoxia-preconditioned blood-derived secretomes and, therefore, their potential application as tools for promoting therapeutic angiogenesis.


Assuntos
Secretoma , Cloreto de Sódio , Humanos , Meios de Cultivo Condicionados/farmacologia , Hipóxia Celular , Neovascularização Fisiológica , Hipóxia , Peptídeos e Proteínas de Sinalização Intercelular
4.
Int J Mol Sci ; 24(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36768283

RESUMO

Strategies for therapeutic lymphangiogenesis are gradually directed toward the use of growth factor preparations. In particular, blood-derived growth factor products, including Hypoxia Preconditioned Serum (HPS) and Platelet-rich Plasma (PRP), are both clinically employed for accelerating tissue repair and have received considerable attention in the field of regenerative medicine research. In this study, a comparative analysis of HPS and PRP was conducted to explore their lymphangiogenic potential. We found higher pro-lymphangiogenic growth factor concentrations of VEGF-C, PDGF-BB, and bFGF in HPS in comparison to normal serum (NS) and PRP. The proliferation and migration of lymphatic endothelial cells (LECs) were promoted considerably with both HPS and PRP, but the strongest effect was achieved with HPS-40% dilution. Tube formation of LECs showed the highest number of tubes, branching points, greater tube length, and cell-covered area with HPS-10%. Finally, the effects were double-validated using an ex vivo lymphatic ring assay, in which the highest number of sprouts and the greatest sprout length were achieved with HPS-10%. Our findings demonstrate the superior lymphangiogenic potential of a new generation blood-derived secretome obtained by hypoxic preconditioning of peripheral blood cells-a method that offers a novel alternative to PRP.


Assuntos
Células Endoteliais , Peptídeos e Proteínas de Sinalização Intercelular , Linfangiogênese , Plasma Rico em Plaquetas , Soro , Cicatrização , Células Endoteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Linfangiogênese/fisiologia , Plasma Rico em Plaquetas/química , Plasma Rico em Plaquetas/metabolismo , Precondicionamento Isquêmico , Soro/química , Soro/metabolismo , Cicatrização/fisiologia
5.
Int J Mol Sci ; 24(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37445617

RESUMO

Autologous chondrocyte implantation (ACI) for the treatment of articular cartilage defects remains challenging in terms of maintaining chondrogenic phenotype during in vitro chondrocyte expansion. Growth factor supplementation has been found supportive in improving ACI outcomes by promoting chondrocyte redifferentiation. Here, we analysed the chondrogenic growth factor concentrations in the human blood-derived secretome of Hypoxia Preconditioned Serum (HPS) and assessed the effect of HPS-10% and HPS-40% on human articular chondrocytes from osteoarthritic cartilage at different time points compared to normal fresh serum (NS-10% and NS-40%) and FCS-10% culture conditions. In HPS, the concentrations of TGF-beta1, IGF-1, bFGF, PDGF-BB and G-CSF were found to be higher than in NS. Chondrocyte proliferation was promoted with higher doses of HPS (HPS-40% vs. HPS-10%) and longer stimulation (4 vs. 2 days) compared to FCS-10%. On day 4, immunostaining of the HPS-10%-treated chondrocytes showed increased levels of collagen type II compared to the other conditions. The promotion of the chondrogenic phenotype was validated with quantitative real-time PCR for the expression of collagen type II (COL2A1), collagen type I (COL1A1), SOX9 and matrix metalloproteinase 13 (MMP13). We demonstrated the highest differentiation index (COL2A1/COL1A1) in HPS-10%-treated chondrocytes on day 4. In parallel, the expression of differentiation marker SOX9 was elevated on day 4, with HPS-10% higher than NS-10/40% and FCS-10%. The expression of the cartilage remodelling marker MMP13 was comparable across all culture conditions. These findings implicate the potential of HPS-10% to improve conventional FCS-based ACI culture protocols by promoting the proliferation and chondrogenic phenotype of chondrocytes during in vitro expansion.


Assuntos
Cartilagem Articular , Condrócitos , Humanos , Cartilagem Articular/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Condrócitos/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Matriz Extracelular/metabolismo , Hipóxia/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Fenótipo
6.
Lasers Med Sci ; 37(5): 2457-2470, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35067818

RESUMO

We assessed the impact of photobiomodulation (PBM) plus adipose-derived stem cells (ASCs) during the anabolic and catabolic stages of bone healing in a rat model of a critical size femoral defect (CSFD) that was filled with a decellularized bone matrix (DBM). Stereological analysis and gene expression levels of bone morphogenetic protein 4 (BMP4), Runt-related transcription factor 2 (RUNX2), and stromal cell-derived factor 1 (SDF1) were determined. There were six groups of rats. Group 1 was the untreated control or DBM. Study groups 2-6 were treated as follows: ASC (ASC transplanted into DBM, then implanted in the CSFD); PBM (CSFD treated with PBM); irradiated ASC (iASC) (ASCs preconditioned with PBM, then transplanted into DBM, and implanted in the CSFD); ASC + PBM (ASCs transplanted into DBM, then implanted in the CSFD, followed by PBM administration); and iASC + PBM (the same as iASC, except CSFDs were exposed to PBM). At the anabolic step, all treatment groups had significantly increased trabecular bone volume (TBV) (24.22%) and osteoblasts (83.2%) compared to the control group (all, p = .000). However, TBV in group iASC + PBM groups were superior to the other groups (97.48% for osteoblast and 58.8% for trabecular bone volume) (all, p = .000). The numbers of osteocytes in ASC (78.2%) and iASC + PBM (30%) groups were remarkably higher compared to group control (both, p = .000). There were significantly higher SDF (1.5-fold), RUNX2 (1.3-fold), and BMP4 (1.9-fold) mRNA levels in the iASC + PBM group compared to the control and some of the treatment groups. At the catabolic step of bone healing, TBV increased significantly in PBM (30.77%), ASC + PBM (32.27%), and iASC + PBM (35.93%) groups compared to the control group (all, p = .000). There were significantly more osteoblasts and osteocytes in ASC (71.7%, 62.02%) (p = .002, p = .000); PBM (82.54%, 156%), iASC (179%, 23%), and ASC + PBM (108%, 110%) (all, p = .000), and iASC + PBM (79%, 100.6%) (p = .001, p = .000) groups compared to control group. ASC preconditioned with PBM in vitro plus PBM in vivo significantly increased stereological parameters and SDF1, RUNX2, and BMP4 mRNA expressions during bone healing in a CSFD model in rats.


Assuntos
Osso e Ossos , Subunidade alfa 1 de Fator de Ligação ao Core , Terapia com Luz de Baixa Intensidade , Células-Tronco , Tecido Adiposo/citologia , Animais , Proteína Morfogenética Óssea 4 , Osso e Ossos/lesões , Quimiocina CXCL12 , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Expressão Gênica , Humanos , RNA Mensageiro , Ratos
7.
J Cell Physiol ; 236(6): 4515-4527, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33442879

RESUMO

Ischemic preconditioned (IP) neurons protect astrocytes against ischemia/reperfusion (I/R)-induced injury by inhibiting oxidative stress. However, the relevant mechanisms are unknown. Based on the role of nuclear factor-κB (NF-κB) in cell survival and adaption to oxidative stress, we hypothesized that NF-κB might be associated with astroprotection induced by IP neurons via upregulation of antioxidant enzymes. Here, we investigated the effects of IP neurons on NF-κB activation, cell viability, reactive oxygen species (ROS), expression of antioxidant enzymes, erythropoietin (EPO), and tumor necrosis factor α (TNF-α), in the presence or absence of BAY11-7082 (an NF-κB inhibitor), anti-EPO, and anti-TNF-α antibodies, in astrocytes treated with or without I/R. We found that IP neurons could keep NF-κB activation at a relatively higher but beneficial level, and in turn, upregulated the activity of antioxidant enzymes and hence enhanced cell viability and reduced ROS in I/R treated astrocytes. The results collectively indicated that IP neurons are able to significantly inhibit the I/R-induced NF-κB overactivation, probably via EPO and TNF-α, being essential for IP neuron-induced astroprotection under the conditions of I/R. We concluded that NF-κB-mediated antioxidative stress is one of the mechanisms by which IP neurons protect astrocytes against I/R injury.


Assuntos
Astrócitos/metabolismo , Córtex Cerebral/metabolismo , NF-kappa B/metabolismo , Neurônios/metabolismo , Comunicação Parácrina , Traumatismo por Reperfusão/prevenção & controle , Animais , Antioxidantes/metabolismo , Astrócitos/enzimologia , Astrócitos/patologia , Hipóxia Celular , Células Cultivadas , Córtex Cerebral/patologia , Meios de Cultivo Condicionados/metabolismo , Eritropoetina/metabolismo , Glucose/deficiência , Neurônios/patologia , Estresse Oxidativo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
8.
J Electrocardiol ; 62: 190-199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32977208

RESUMO

The inverse problem of electrocardiography (ECG) of computing epicardial potentials from body surface potentials, is an ill-posed problem and needs to be solved by regularization techniques. The L2-norm regularization can cause considerable smoothing of the solution, while the L1-norm scheme promotes a solution with sharp boundaries/gradients between piecewise smooth regions, so L1-norm is widely used in the ECG inverse problem. However, large amount of computation and long computation time are needed in the L1-norm scheme. In this paper, by combining iterative reweight norm (IRN) with a factorization-free preconditioned LSQR algorithm (MLSQR), a new IRN-MLSQR method was proposed to accelerate the convergence speed of the L1-norm scheme. We validated the IRN-MLSQR method using experimental data from isolated canine hearts and clinical procedures in the electrophysiology laboratory. The results showed that the IRN-MLSQR method can significantly reduce the number of iterations and operation time while ensuring the calculation accuracy. The number of iterations of the IRN-MLSQR method is about 60%-70% that of the conventional IRN method, and at the same time, the accuracy of the solution is almost the same as that of the conventional IRN method. The proposed IRN-MLSQR method may be used as a new approach to the inverse problem of ECG.


Assuntos
Eletrocardiografia , Modelos Cardiovasculares , Algoritmos , Animais , Cães , Coração
9.
Int J Mol Sci ; 21(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977637

RESUMO

Mesenchymal stem cells (MSCs) are a useful source for cell-based therapy of a variety of immune-mediated diseases, including neurodegenerative disorders. However, poor migration ability and survival rate of MSCs after brain transplantation hinder the therapeutic effects in the disease microenvironment. Therefore, we attempted to use a preconditioning strategy with pharmacological agents to improve the cell proliferation and migration of MSCs. In this study, we identified ethionamide via the screening of a drug library, which enhanced the proliferation of MSCs. Preconditioning with ethionamide promoted the proliferation of Wharton's jelly-derived MSCs (WJ-MSCs) by activating phosphatidylinositol 3-kinase (PI3K)/Akt and mitogen-activated protein kinase/extracellular signal-regulated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK)1/2 signaling. Preconditioning with ethionamide also enhanced the migration ability of MSCs by upregulating expression of genes associated with migration, such as C-X-C motif chemokine receptor 4 (CXCR4) and C-X-C motif chemokine ligand 12 (CXCL12). Furthermore, preconditioning with ethionamide stimulated the secretion of paracrine factors, including neurotrophic and growth factors in MSCs. Compared to naïve MSCs, ethionamide-preconditioned MSCs (ETH-MSCs) were found to survive longer in the brain after transplantation. These results suggested that enhancing the biological process of MSCs induced by ethionamide preconditioning presents itself as a promising strategy for enhancing the effectiveness of MSCs-based therapies.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Etionamida/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Xenoenxertos , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Camundongos
10.
J Cell Physiol ; 234(7): 10942-10963, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30537190

RESUMO

Wnt/ß-catenin signaling pathway plays a crucial role in diabetic cardiomyopathy (DCM), thus we aimed at investigating the effect of one therapeutic approach with resveratrol (RSV) given systemically and combined treatment of RSV with mesenchymal stem cells (MSCs) that was either RSV-preconditioned or not on Wnt/ß-catenin signaling pathway in streptozotocin-induced DCM, and to evaluate effects of RSV preconditioning on MSCs therapeutic potential. The rats were divided into control (C, n = 8), diabetic (DM, n = 8), diabetic treated with systemic RSV (DM-RSV, n = 8), diabetic treated with RSV and nonconditioned MSCs (DM-RSV-MSCs, n = 8), diabetic treated with RSV and RSV-incubated with MSCs (DM-RSV-MSCc, n = 8) and diabetic treated with RSV-conditioned MSCs (DM-MSCc, n = 8). Echocardiography (Echo) showed significant improvement of cardiac functions in all groups treated with RSV either systemic or added in culture media. Data of ejection fraction (EF%) of DM-RSV-MSCc (81.50; interquartile range [IQR], 80.00-83.00) was comparable to both DM-RSV-MSCs (77.50; IQR, 71.50-79.00), and DM-MSCc (71.50; IQR, 70.00-74.50). Histological examination of the left ventricles was performed for all groups. DM group revealed significant myocardial hypertrophy, apoptosis, interstitial fibrosis, and microvascular affection. All treated groups were associated, in variable degrees, with attenuation of cardiac hypertrophy and fibrosis, decreased area% for cardiac immunostaining of secreted frizzled-related protein (sFRP2) and Wnt/ß-catenin and improvement of the microvasculature. In conclusion, MSCs pretreated with resveratrol for 7 days showed increased 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and combined use of RSV (systemically and in culture media) significantly could improve cardiac remodeling capacity of MSCs via attenuation of sFRP2-mediated fibrosis and the downstream Wnt/ß-catenin pathway.


Assuntos
Antioxidantes/uso terapêutico , Cardiomiopatias Diabéticas/terapia , Fibrose/terapia , Células-Tronco Mesenquimais/efeitos dos fármacos , Resveratrol/uso terapêutico , Animais , Mau Alinhamento Ósseo , Diabetes Mellitus Experimental/complicações , Masculino , Transplante de Células-Tronco Mesenquimais , Distribuição Aleatória , Ratos , Ratos Wistar
11.
J Cell Biochem ; 119(12): 10301-10313, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30145846

RESUMO

Poor survival of stem cells in the harsh microenvironment at the site of stroke, especially during acute phase of injury, remains a serious obstacle to achieve the desired prognosis. We hypothesized that combined treatment of neural stem cells (NSCs) with small molecules would precondition them to become robust and survive better as compared with the native nonpreconditioned cells. Mouse ganglionic NSCs were isolated, cultured, and characterized. The cells were preconditioned by treatment with sodium butyrate (NaB) and nicorandil (Nico) and transplanted in an experimentally induced stroke model. Sham-operated animals without treatment or animals with experimental stroke treated with basal medium, native NSCs, NSCs preconditioned with NaB or Nico alone were used as controls. The tissue samples and cells with different treatments were used to measure brain-tissue-derived neurotrophic factor (BDNF) level and the activity of phosphatidylinositol-3 kinase (PI3K), apurinic/apyrimidinic endonuclease 1 (APE1), and nuclear factor-κB (NF-κB) p50 both in vitro and in vivo, respectively. Additionally, survival of the cells and recovery indices for stroke were studied. The combined treatment with NaB + Nico resulted in increased BDNF level and higher PI3K, APE1, and the downstream NF-κB activation, which were blocked by pretreatment with their respective inhibitors. Donor cell survival increased postengraftment as assessed by 5-bromo-2'-deoxyuridine immunostaining and reduced Terminal deoxynucleotide transferase dUTP Nick End Labeling positivity at the site of engraftment. There was reduction in proinflammatory cytokines and infiltration of both GFAP + and CD68 + at the injury site. There was reduction in the infarct size and neurological function was preserved in the preconditioned cell treatment group. Our preconditioning approach with small molecules effectively improved the survival as well as functionality of NSCs.


Assuntos
Microambiente Celular/efeitos dos fármacos , Células-Tronco Neurais/transplante , Neurônios/transplante , Acidente Vascular Cerebral/terapia , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Ácido Butírico/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Microambiente Celular/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Humanos , Camundongos , NF-kappa B/genética , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/patologia , Nicorandil/farmacologia , Fosfatidilinositol 3-Quinases/genética , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologia
12.
Sensors (Basel) ; 18(7)2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-30021989

RESUMO

The GaoFen-3 (GF-3) satellite is the only synthetic aperture radar (SAR) satellite in the High-Resolution Earth Observation System Project, which is the first C-band full-polarization SAR satellite in China. In this paper, we proposed some error sources-based weight strategies to improve the geometric performance of multi-mode GF-3 satellite SAR images without using ground control points (GCPs). To get enough tie points, a robust SAR image registration method and the SAR-features from accelerated segment test (SAR-FAST) method is used to achieve the image registration and tie point extraction. Then, the original position of these tie points in object-space is calculated with the help of the space intersection method. With the dataset clustered by the density-based spatial clustering of applications with noise (DBSCAN) algorithm, we undertake the block adjustment with a bias-compensated rational function model (RFM) aided to improve the geometric performance of these multi-mode GF-3 satellite SAR images. Different weight strategies are proposed to develop the normal equation matrix according to the error sources analysis of GF-3 satellite SAR images, and the preconditioned conjugate gradient (PCG) method is utilized to solve the normal equation. The experimental results indicate that our proposed method can improve the geometric positioning accuracy of GF-3 satellite SAR images within 2 pixels.

13.
J Mol Cell Cardiol ; 104: 17-30, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28130118

RESUMO

Adipose-derived stem cell (ADSC) transplantation is a promising new therapy to improve cardiac function after myocardial infarction. However, its low efficacy of transdifferentiation hampers its usefulness. Glycogen synthase kinase-3ß (GSK-3ß) signal has been shown to play a role in preconditioning-induced cardioprotection. We assessed whether n-butylidenephthalide (BP) primed ADSCs can attenuate arrhythmias by a GSK-3ß-dependent pathway after myocardial infarction. Male Wistar rats after coronary ligation was randomly allocated to receive intramyocardial injection of vehicle, ADSCs, BP-preconditioned ADSCs, (BP+lithium)-preconditioned ADSCs, (BP+SB216763)-preconditioned ADSCs, and (BP+LY294002)-preconditioned ADSCs. ADSCs were primed for 16h before implantation. After 4weeks of implantation, ADSCs were retained in myocardium, reduced fibrosis and improved cardiac function. Sympathetic hyperinnervation was blunted after administering ADSCs, assessed by immunofluorescent analysis, and Western blotting and real-time quantitative RT-PCR of nerve growth factor. Arrhythmic scores during programmed stimulation in the ADSC-treated infarcted rats were significantly lower than vehicle. BP-preconditioned ADSCs had superior cardioprotection, greater ADSC engraftment and transdifferentiation, and antiarrhythmic effects compared with ADSCs alone. Simultaneously, BP increased the levels of phospho-Akt and down-regulated GSK-3ß activity. The effects of BP against sympathetic hyperinnervation were blocked by LY294002, a PI3K inhibitor. Addition of either lithium or SB216763 did not have additional effects compared with BP alone. Compared with ADSC alone, BP-primed ADSC implantation improved stem cell engraftment and attenuated sympathetic hyperinnervation and arrhythmias through a PI3K/Akt/GSK-3ß-dependent pathway, suggesting that a synergic action was achieved between BP pretreatment and ADSCs.


Assuntos
Tecido Adiposo/citologia , Células-Tronco Adultas/metabolismo , Arritmias Cardíacas/etiologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Infarto do Miocárdio/complicações , Infarto do Miocárdio/metabolismo , Fator de Crescimento Neural/metabolismo , Transdução de Sinais , Células-Tronco Adultas/efeitos dos fármacos , Animais , Arritmias Cardíacas/diagnóstico , Biomarcadores , Transdiferenciação Celular/efeitos dos fármacos , Ecocardiografia , Fibrose , Testes de Função Cardíaca , Hemodinâmica , Humanos , Imuno-Histoquímica , Masculino , Infarto do Miocárdio/diagnóstico , Neovascularização Patológica , Fenótipo , Anidridos Ftálicos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transplante de Células-Tronco
14.
J Comput Chem ; 36(20): 1521-35, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26058451

RESUMO

A new low-memory modification of the density fitting approximation based on a combination of a continuous fast multipole method (CFMM) and a preconditioned conjugate gradient solver is presented. Iterative conjugate gradient solver uses preconditioners formed from blocks of the Coulomb metric matrix that decrease the number of iterations needed for convergence by up to one order of magnitude. The matrix-vector products needed within the iterative algorithm are calculated using CFMM, which evaluates them with the linear scaling memory requirements only. Compared with the standard density fitting implementation, up to 15-fold reduction of the memory requirements is achieved for the most efficient preconditioner at a cost of only 25% increase in computational time. The potential of the method is demonstrated by performing density functional theory calculations for zeolite fragment with 2592 atoms and 121,248 auxiliary basis functions on a single 12-core CPU workstation.

16.
J Dairy Sci ; 97(6): 3943-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24679933

RESUMO

Computing the inverse of the genomic relationship matrix using recursion was investigated. A traditional algorithm to invert the numerator relationship matrix is based on the observation that the conditional expectation for an additive effect of 1 animal given the effects of all other animals depends on the effects of its sire and dam only, each with a coefficient of 0.5. With genomic relationships, such an expectation depends on all other genotyped animals, and the coefficients do not have any set value. For each animal, the coefficients plus the conditional variance can be called a genomic recursion. If such recursions are known, the mixed model equations can be solved without explicitly creating the inverse of the genomic relationship matrix. Several algorithms were developed to create genomic recursions. In an algorithm with sequential updates, genomic recursions are created animal by animal. That algorithm can also be used to update a known inverse of a genomic relationship matrix for additional genotypes. In an algorithm with forward updates, a newly computed recursion is immediately applied to update recursions for remaining animals. The computing costs for both algorithms depend on the sparsity pattern of the genomic recursions, but are lower or equal than for regular inversion. An algorithm for proven and young animals assumes that the genomic recursions for young animals contain coefficients only for proven animals. Such an algorithm generates exact genomic EBV in genomic BLUP and is an approximation in single-step genomic BLUP. That algorithm has a cubic cost for the number of proven animals and a linear cost for the number of young animals. The genomic recursions can provide new insight into genomic evaluation and possibly reduce costs of genetic predictions with extremely large numbers of genotypes.


Assuntos
Cruzamento , Bovinos/genética , Genoma , Linhagem , Algoritmos , Animais , Genótipo , Modelos Genéticos
17.
Adv Sci (Weinh) ; 11(34): e2404275, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38973294

RESUMO

Intervertebral disc degeneration (IVDD) is a chronic degenerative disease involving the aging and loss of proliferative capacity of nucleus pulposus cells (NPCs), processes heavily dependent on mitochondrial dynamics and autophagic flux. This study finds that the absence of BCL2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3) is associated with senescence-related NPC degeneration, disrupting mitochondrial quality control. Bone marrow mesenchymal stem cells (BMSCs) have multidirectional differentiation potential and produce extracellular vesicles containing cellular activators. Therefore, in this study, BMSCs are induced under hypoxic stimulation to deliver BNIP3-rich extracellular vesicles to NPCs, thereby alleviating aging-associated mitochondrial autophagic flux, promoting damaged mitochondrial clearance, and restoring mitochondrial quality control. Mechanistically, BNIP3 is shown to interact with the membrane-bound protein annexin A2 (ANXA2), enabling the liberation of the transcription factor EB (TFEB) from the ANXA2-TFEB complex, promoting TFEB nuclear translocation, and regulating autophagy and lysosomal gene activation. Furthermore, a rat model of IVDD is established and verified the in vivo efficacy of the exosomes in repairing disc injuries, delaying NPC aging, and promoting extracellular matrix (ECM) synthesis. In summary, hypoxia-induced BMSC exosomes deliver BNIP3-rich vesicles to alleviate disc degeneration by activating the mitochondrial BNIP3/ANXA2/TFEB axis, providing a new target for IVDD treatment.


Assuntos
Exossomos , Degeneração do Disco Intervertebral , Células-Tronco Mesenquimais , Mitofagia , Animais , Humanos , Masculino , Ratos , Modelos Animais de Doenças , Exossomos/metabolismo , Hipóxia/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/terapia , Degeneração do Disco Intervertebral/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Células-Tronco Mesenquimais/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Mitofagia/fisiologia , Mitofagia/genética , Núcleo Pulposo/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Ratos Sprague-Dawley
18.
Artigo em Inglês | MEDLINE | ID: mdl-38468534

RESUMO

BACKGROUND: Type 1 diabetes mellitus (T1DM) is a condition marked by elevated blood sugar levels and primarily recognized by the destruction of beta cells caused by an autoimmune attack, which is a significant characteristic of T1DM. Recent studies have demonstrated the regenerative potential of conditioned medium therapy. In light of this, the current research sought to assess the impact of Mesenchymal Stem Cell conditioned media (CM) and CM with resveratrol (CM+ Resveratrol) on the management of T1DM in Swiss albino mice. By leveraging and modifying existing conditioned medium therapy, this study aims to evaluate its effectiveness in treating T1DM. MATERIALS & METHODS: Diabetes was induced in animals using the diabetes-inducing agent streptozotocin (STZ). The animals were then divided into five groups: Normal control, Disease Control, Resveratrol, Condition Media, and CM + Resveratrol. Treatments were given to the animals accordingly. The study period was 28 days. During this time, the animals were monitored for foodwater intake twice a week, blood glucose levels, and body weight. At the conclusion of the 28-day study period, biochemical estimations were performed for serum insulin levels, C-peptide levels, anti-inflammatory cytokines levels and pro-inflammatory cytokines levels. Additionally, histopathology of the pancreas was performed. RESULTS: The test groups showed a significant decrease in blood glucose levels, an increase in Cpeptide levels, and a decrease in pro-inflammatory cytokine levels compared to the disease group. However, no statistically significant change within groups was observed in terms of serum insulin and anti-inflammatory cytokine levels. The improvement in diabetic symptoms, such as polyphagia, polydipsia, and weight loss, was observed in the treatment group, along with pancreatic regeneration, which indicated improved insulin secretion. CONCLUSION: In the current investigation, we concluded that CM and CM+ Resveratrol, as natural immunomodulators, have the capacity to regenerate injured pancreatic beta cells and have antidiabetic action, together with immunomodulating impact. Nonetheless, future studies on this therapy appear to be promising.

19.
Mil Med Res ; 11(1): 48, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39034405

RESUMO

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder characterized by the degeneration of dopaminergic neurons in the substantia nigra (SN). Activation of the neuroinflammatory response has a pivotal role in PD. Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic approach for various nerve injuries, but there are limited reports on their use in PD and the underlying mechanisms remain unclear. METHODS: We investigated the effects of clinical-grade hypoxia-preconditioned olfactory mucosa (hOM)-MSCs on neural functional recovery in both PD models and patients, as well as the preventive effects on mouse models of PD. To assess improvement in neuroinflammatory response and neural functional recovery induced by hOM-MSCs exposure, we employed single-cell RNA sequencing (scRNA-seq), assay for transposase accessible chromatin with high-throughput sequencing (ATAC-seq) combined with full-length transcriptome isoform-sequencing (ISO-seq), and functional assay. Furthermore, we present the findings from an initial cohort of patients enrolled in a phase I first-in-human clinical trial evaluating the safety and efficacy of intraspinal transplantation of hOM-MSC transplantation into severe PD patients. RESULTS: A functional assay identified that transforming growth factor-ß1 (TGF-ß1), secreted from hOM-MSCs, played a critical role in modulating mitochondrial function recovery in dopaminergic neurons. This effect was achieved through improving microglia immune regulation and autophagy homeostasis in the SN, which are closely associated with neuroinflammatory responses. Mechanistically, exposure to hOM-MSCs led to an improvement in neuroinflammation and neural function recovery partially mediated by TGF-ß1 via activation of the anaplastic lymphoma kinase/phosphatidylinositol-3-kinase/protein kinase B (ALK/PI3K/Akt) signaling pathway in microglia located in the SN of PD patients. Furthermore, intraspinal transplantation of hOM-MSCs improved the recovery of neurologic function and regulated the neuroinflammatory response without any adverse reactions observed in patients with PD. CONCLUSIONS: These findings provide compelling evidence for the involvement of TGF-ß1 in mediating the beneficial effects of hOM-MSCs on neural functional recovery in PD. Treatment and prevention of hOM-MSCs could be a promising and effective neuroprotective strategy for PD. Additionally, TGF-ß1 may be used alone or combined with hOM-MSCs therapy for treating PD.


Assuntos
Modelos Animais de Doenças , Células-Tronco Mesenquimais , Mucosa Olfatória , Doença de Parkinson , Fator de Crescimento Transformador beta1 , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Transplante de Células-Tronco Mesenquimais/métodos , Doença de Parkinson/complicações , Doença de Parkinson/terapia , Recuperação de Função Fisiológica , Fator de Crescimento Transformador beta1/metabolismo
20.
Prev Vet Med ; 212: 105838, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36634490

RESUMO

Health preconditioning programmes have recently gained increased attention in South Africa. Uncertainty remains about whether South African feedlot operators and cow-calf producers perceive health preconditioning as an economic value-added management practice. Results indicated that most feedlot operators were willing to pay average price premiums of R0.58/kg, R0.83/kg and R1.02/kg for a basic, intermediate and comprehensive health preconditioning programme, respectively. Cow-calf producers were willing to accept average price premiums of R0.49/kg, R0.72/kg and R0.83/kg for the programmes. The findings provide information that could contribute to potential market development for health-preconditioned weaners in developing countries and could significantly aid in improving efficiency and herd health within beef industries worldwide.


Assuntos
Criação de Animais Domésticos , Doenças dos Bovinos , Feminino , Animais , Bovinos , África do Sul , Criação de Animais Domésticos/métodos , Incerteza
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