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1.
Nature ; 627(8003): 313-320, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480964

RESUMO

Intrinsically stretchable electronics with skin-like mechanical properties have been identified as a promising platform for emerging applications ranging from continuous physiological monitoring to real-time analysis of health conditions, to closed-loop delivery of autonomous medical treatment1-7. However, current technologies could only reach electrical performance at amorphous-silicon level (that is, charge-carrier mobility of about 1 cm2 V-1 s-1), low integration scale (for example, 54 transistors per circuit) and limited functionalities8-11. Here we report high-density, intrinsically stretchable transistors and integrated circuits with high driving ability, high operation speed and large-scale integration. They were enabled by a combination of innovations in materials, fabrication process design, device engineering and circuit design. Our intrinsically stretchable transistors exhibit an average field-effect mobility of more than 20 cm2 V-1 s-1 under 100% strain, a device density of 100,000 transistors per cm2, including interconnects and a high drive current of around 2 µA µm-1 at a supply voltage of 5 V. Notably, these achieved parameters are on par with state-of-the-art flexible transistors based on metal-oxide, carbon nanotube and polycrystalline silicon materials on plastic substrates12-14. Furthermore, we realize a large-scale integrated circuit with more than 1,000 transistors and a stage-switching frequency greater than 1 MHz, for the first time, to our knowledge, in intrinsically stretchable electronics. Moreover, we demonstrate a high-throughput braille recognition system that surpasses human skin sensing ability, enabled by an active-matrix tactile sensor array with a record-high density of 2,500 units per cm2, and a light-emitting diode display with a high refreshing speed of 60 Hz and excellent mechanical robustness. The above advancements in device performance have substantially enhanced the abilities of skin-like electronics.


Assuntos
Desenho de Equipamento , Pele , Transistores Eletrônicos , Dispositivos Eletrônicos Vestíveis , Humanos , Silício , Nanotubos de Carbono , Tato
3.
FASEB J ; 37(1): e22691, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36515680

RESUMO

Macrophages (Mφ) infiltration is a common characteristic of acute kidney injury (AKI). Exosomes-mediated cell communication between tubular epithelial cells (TECs) and Mφ has been suggested to be involved in AKI. Exosomes-derived from injured TECs could regulate Mφ polarization during AKI. However, little is known regarding how activated Mφ regulates kidney injury. To explore the role of activated Mφ in the AKI process, we revealed that Mφ-derived exosomes from AKI mice (ExosAKI ) caused mitochondria damage and induced TECs injury. Then, we detected the global miRNA expression profiles of MφNC and MφAKI and found that among the upregulated miRNAs, miR-195a-5p, which regulates mitochondria metabolism in cancer, was significantly increased in MφAKI . Due to the enrichment of miR-195a-5p in ExosAKI , the miR-195a-5p level in the kidney was elevated in AKI mice. More interestingly, based on the high expression of pri-miR-195a-5p in kidney-infiltrated Mφ, and the reduction of miR-195a-5p in kidney after depletion of Mφ in AKI mice, we confirmed that miR-195a-5p may be produced in infiltrated Mφ, and shuttled into TECs via ExosMφ . Furthermore, in vitro inhibition of miR-195a-5p alleviated the effect of ExosAKI induced mitochondrial dysfunction and cell injury. Consistently, antagonizing miR-195a-5p with a miR-195a-5p antagomir attenuated cisplatin-induced kidney injury and mitochondrial dysfunction in mice. These findings revealed that the Mφ exosomal miR-195a-5p derived from AKI mice played a critical pathologic role in AKI progression, representing a new therapeutic target for AKI.


Assuntos
Injúria Renal Aguda , Exossomos , MicroRNAs , Camundongos , Animais , Injúria Renal Aguda/metabolismo , Exossomos/metabolismo , Células Epiteliais/metabolismo , MicroRNAs/metabolismo , Mitocôndrias/metabolismo , Macrófagos/metabolismo
4.
Exp Cell Res ; 429(2): 113655, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37253404

RESUMO

Lipotoxicity caused by excess free fatty acids, particularly saturated fatty acids (SFAs) such as palmitic acid (PA), is one of the most important pathogenesis of nonalcoholic fatty liver disease (NAFLD). However, unsaturated fatty acids (UFAs), such as oleic acid (OA), are nontoxic and can combat SFA-induced toxicity through alleviation of cell apoptosis, endoplasmic reticulum stress (ER stress) and lipids metabolism disorder. However, whether OA is able to regulate autophagy is largely unknown. So, this study aims to investigate the mechanism underlying OA mediated modulation of autophagy in hepatocytes and mice with NAFLD. In vitro, human hepatoma cell line HepG2 cells, human normal liver cells L-02 and mouse normal liver cells AML12 were treated with palmitic acid (PA)/tunicamycin (TM) or/and OA for 48 h. In vivo, C57/BL6 mice were fed with high fat diet (HFD) to induce NAFLD. And the HFD was partial replaced by olive oil to observe the protective effects of olive oil. We demonstrated that PA/TM impaired cell viability and induced cellular apoptosis in HepG2 cells and L-02 cells. Moreover, PA/TM induced autophagy impairment by reducing the nuclear translocation of transcription factor EB (TFEB) and inhibiting the activity of CTSB. However, OA substantially alleviated PA/TM induced cellular apoptosis and autophagy dysfunction in hepatocytes. Additionally, restoring autophagy function is able to reduce ER stress. Similarly, HFD for 20 weeks successfully established NAFLD model in C57/BL6 mice, and significant autophagy impairment were observed in liver tissues. Noteworthily, 30% replacement of HFD with olive oil had profoundly reversed NAFLD. It significantly impoved steatosis, and reduced autophagy dysfunction, ER stress and apoptosis in liver tissue. Conclusively, these data demonstrated that OA is able to effectively impove autophagy dysfunction under the context of both PA and ER stress inducer induced lipotoxicity, and OA mediated regulation of lysosome dysfunction through TFEB plays an important role, suggesting that the regulation of ER stress-autophagy axis is a critical mechanism in OA driven protection in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Humanos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ácido Oleico/farmacologia , Ácido Oleico/metabolismo , Azeite de Oliva/metabolismo , Azeite de Oliva/farmacologia , Fígado/metabolismo , Hepatócitos/metabolismo , Ácido Palmítico/farmacologia , Autofagia , Estresse do Retículo Endoplasmático , Dieta Hiperlipídica/efeitos adversos
5.
Pharmacol Res ; 192: 106788, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37146925

RESUMO

Senescence of bone marrow mesenchymal stem cells (BMSCs) is one of the leading causes of osteoporosis. SIRT3, an essential NAD-dependent histone deacetylase, is highly correlated with BMSC senescence-mediated bone degradation and mitochondrial/heterochromatic disturbance. S-sulfhydration of cysteine residues favorably enhances SIRT3 activity by forming persulfides. Nevertheless, the underlying molecular mechanism of SIRT3 S-sulfhydration on mitochondrial/heterochromatic homeostasis involved in BMSC senescence remains unknown. Here, we demonstrated that CBS and CSE, endogenous hydrogen sulfide synthases, are downregulated with BMSC senescence. Exogenous H2S donor NaHS-mediated SIRT3 augmentation rescued the senescent phenotypes of BMSCs. Conversely, SIRT3 deletion accelerated oxidative stress-induced BMSC senescence through mitochondrial dysfunction and the detachment of the heterochromatic protein H3K9me3 from the nuclear envelope protein Lamin B1. H2S-mediated SIRT3 S-sulfhydration modification rescued the disorganized heterochromatin and fragmented mitochondria induced by the S-sulfhydration inhibitor dithiothreitol, thus leading to elevated osteogenic capacity and preventing BMSC senescence. The antisenescence effect of S-sulfhydration modification on BMSCs was abolished when the CXXC sites of the SIRT3 zinc finger motif were mutated. In vivo, aged mice-derived BMSCs pretreated with NaHS were orthotopically transplanted to the ovariectomy-induced osteoporotic mice, and we proved that SIRT3 ameliorates bone loss by inhibiting BMSC senescence. Overall, our study for the first time indicates a novel role of SIRT3 S-sulfhydration in stabilizing heterochromatin and mitochondrial homeostasis in counteracting BMSC senescence, providing a potential target for the treatment of degenerative bone diseases.


Assuntos
Osteoporose , Sirtuína 3 , Feminino , Camundongos , Animais , Sirtuína 3/genética , Sirtuína 3/metabolismo , Heterocromatina/metabolismo , Osteoporose/metabolismo , Mitocôndrias/metabolismo , Senescência Celular
6.
J Cell Mol Med ; 26(13): 3702-3715, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35650472

RESUMO

Cisplatin is extensively used to treat malignancies. However, its clinical use is always limited due to the serious side effects, especially the nephrotoxicity. Matrine (MAT), a tetracyclic quinolizine alkaloid found in sophora genus, exerts multiple pharmacological roles, including anti-oxidative stress, anti-inflammation and anti-apoptosis, but the role of MAT on acute kidney injury (AKI) has not been evaluated. Here, we found that MAT potently inhibited cell injury induced by cisplatin in HK2 cells in vitro, which was associated with the inhibition of oxidative injury and NF-κB-mediated inflammation. Moreover, MAT treatment could activate the SIRT3/OPA1 axis and subsequently suppress the mitochondrial fragmentation and improve mitochondrial function. More importantly, SIRT3 knockdown suppressed the deacetylation of OPA1, which blocked the protective role of MAT on cisplatin-induced cell injury. In vivo, MAT treatment alleviated renal dysfunction, histological damage and inflammation induced by cisplatin in mice. Furthermore, consistent with the founding in vitro, MAT also activated SIRT3-mediated deacetylation of OPA1 and alleviated mitochondrial dysfunction in AKI mice. Our study proved that MAT protected against cisplatin-induced AKI by synergic anti-oxidative stress and anti-inflammation actions via SIRT3/OPA1-mediated improvement of mitochondrial function, suggesting that MAT may be a novel and effective strategy for AKI.


Assuntos
Injúria Renal Aguda , Alcaloides , GTP Fosfo-Hidrolases , Quinolizinas , Sirtuína 3 , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Alcaloides/farmacologia , Animais , Cisplatino/efeitos adversos , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Inflamação/metabolismo , Rim/patologia , Camundongos , Mitocôndrias/metabolismo , Quinolizinas/farmacologia , Sirtuína 3/genética , Sirtuína 3/metabolismo , Matrinas
7.
New Phytol ; 234(2): 422-434, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35048364

RESUMO

Root anatomical traits play crucial roles in understanding root functions and root form-function linkages. However, the root anatomy and form-function linkages of monocotyledonous and dicotyledonous herbs remain largely unknown. We measured order-based anatomical traits and mycorrhizal colonization rates of 32 perennial herbs of monocotyledons and dicotyledons in a temperate steppe. For monocots, relative constant proportion of cortex and mycorrhizal colonization rates, but increased cell-wall thickening of the endodermis and proportion of stele were observed across root orders, indicating a slight reduction in absorption capacity and improvement in transportation capacity across orders. For dicots, the cortex and mycorrhizal colonization disappeared in the fourth-order and/or fifth-order roots, whereas the secondary vascular tissue increased markedly, suggesting significant transition of root functions from absorption to transportation across root orders. The allometric relationships between stele and cortex differed across root orders and plant groups, suggesting different strategies to coordinate the absorption and transportation functions among plant groups. In summary, our results revealed different functional transition patterns across root orders and distinct strategies for coordinating the absorption and transportation of root system between monocots and dicots. These findings will contribute to our understanding of the root form and functions in herbaceous species.


Assuntos
Magnoliopsida , Micorrizas , Magnoliopsida/anatomia & histologia , Fenótipo , Raízes de Plantas/anatomia & histologia , Plantas
8.
Stem Cells ; 39(7): 913-928, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33739541

RESUMO

Mesenchymal stem cells (MSCs) have fueled ample translation for treatment of immune-mediated diseases. Our previous study had demonstrated that MSCs could elicit macrophages (Mφ) into anti-inflammatory phenotypes, and alleviate kidney injury in diabetic nephropathy (DN) mice via improving mitochondrial function of Mφ, yet the specific mechanism was unclear. Recent evidence indicated that MSCs communicated with their microenvironment through exchanges of mitochondria. By a coculture system consisting of MSCs and Mφ, we showed that MSCs-derived mitochondria (MSCs-Mito) were transferred into Mφ, and the mitochondrial functions were improved, which contributed to M2 polarization. Furthermore, we found that MSCs-Mito transfer activated peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α)-mediated mitochondrial biogenesis. In addition, PGC-1α interacted with TFEB in high glucose-induced Mφ, leading to the elevated lysosome-autophagy, which was essential to removal of damaged mitochondria. As a result, in Mφ, the mitochondrial bioenergy and capacity to combat inflammatory response were enhanced. Whereas, the immune-regulatory activity of MSCs-Mito was significantly blocked in PGC-1α knockdown Mφ. More importantly, MSCs-Mito transfer could be observed in DN mice, and the adoptive transfer of MSCs-Mito educated Mφ (MφMito ) inhibited the inflammatory response and alleviated kidney injury. However, the kidney-protective effects of MφMito were abolished when the MSCs-Mito was impaired with rotenone, and the similar results were also observed when MφMito were transfected with sipgc-1α before administration. Collectively, these findings suggested that MSCs elicited Mφ into anti-inflammatory phenotype and ameliorated kidney injury through mitochondrial transfer in DN mice, and the effects were relied on PGC-1α-mediated mitochondrial biogenesis and PGC-1α/TFEB-mediated lysosome-autophagy.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Células-Tronco Mesenquimais , Animais , Nefropatias Diabéticas/terapia , Inflamação/metabolismo , Rim , Macrófagos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Mitocôndrias
9.
Stem Cells ; 38(5): 639-652, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31904160

RESUMO

Diabetic nephropathy (DN) is a leading cause of end-stage renal disease. Chronic inflammation is recognized as a key causal factor in the development and progression of DN, and the imbalance of M1/M2 macrophages (Mφ) contributes to this process. Mesenchymal stem cells (MSCs) have been reported to prevent renal injuries via immune regulation in diabetic models, but whether these benefits are owing to the regulation of Mφ, and the underlying signaling pathways are unknown. Here, we showed that MSCs elicited Mφ into M2 phenotype and prevented renal injuries in DN mice, but these effects were abolished when the Mφ were depleted by clodronate liposomes (Lipo-Clod), suggesting that Mφ were necessary for renal protection of MSCs in DN mice. Moreover, the MSCs promoted M2 polarization was attributable to the activation of transcription factor EB (TFEB) and subsequent restore of lysosomal function and autophagy activity in Mφ. Furthermore, in vivo adoptive transfer of Mφin vivo (Mφ from DN + MSCs mice) or MφMSCs (Mφ cocultured with MSCs in vitro) to DN mice improved renal function. While, TFEB knockdown in Mφ significantly abolished the protective role of MφMSCs . Altogether, these findings revealed that MSCs suppress inflammatory response and alleviate renal injuries in DN mice via TFEB-dependent Mφ switch.


Assuntos
Autofagia/genética , Nefropatias Diabéticas/genética , Macrófagos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais , Humanos , Masculino , Camundongos , Fenótipo , Transfecção
10.
Int J Clin Pract ; 75(11): e14811, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34490949

RESUMO

BACKGROUND: Early detection of renal damage in cirrhosis is critical to prevent hepatorenal syndrome (HRS). Although shear wave elastography (SWE) is useful for the assessment of kidney stiffness, no study has yet investigated the clinical feasibility of SWE for predicting HRS. OBJECTIVE: The aim of this study was to evaluate the value of SWE in predicting HRS in patients with cirrhosis and ascites. METHODS: A total of 131 patients with liver cirrhosis and ascites were recruited and followed them for 30 days for the development of AKI. Ultrasonographic examination was performed on all patients at hospital admission. The baseline clinical characteristics, renal biomarkers, renal resistive index (RI) and Young's modulus (YM) were recorded, and their relationship with development HRS was investigated. RESULTS: Sixty-eight patients developed AKI, 23 of them were HRS. Compared with patients in the non-AKI group and non-HRS group, the values of serum cystatin C (CystC), urine neutrophil gelatinase-associated lipocalin (NGAL) and renal RI were significantly increased, while the YM value was significantly decreased in the AKI group and HRS group. Correlation analysis showed that YM was significantly and negatively associated with serum creatinine, serum CystC, urinary NGAL and renal RI in addition to the significant association with the AKI stage. Logistic regression and ROC analysis showed that urine NGAL, renal RI and YM were closely related to the development of HRS. Among them, YM had a good predictive ability in predicting the occurrence of HRS, and the predictive value (AUC = 0.894) was improved when combined with renal RI. CONCLUSION: SWE can indicate renal injury in patients with cirrhosis and ascites. The combination of YM and RI has a good predictive value for the occurrence of HRS.


Assuntos
Injúria Renal Aguda , Técnicas de Imagem por Elasticidade , Síndrome Hepatorrenal , Injúria Renal Aguda/diagnóstico por imagem , Injúria Renal Aguda/etiologia , Ascite/diagnóstico por imagem , Ascite/etiologia , Biomarcadores , Creatinina , Síndrome Hepatorrenal/diagnóstico por imagem , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem
11.
Am J Physiol Endocrinol Metab ; 319(6): E961-E980, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33044844

RESUMO

High levels of plasma free fatty acids (FFAs) lead to endothelial dysfunction (ED), which is involved in the pathogenesis of metabolic syndrome, diabetes, and atherosclerosis. Endoplasmic reticulum (ER) stress and endothelial-to-mesenchymal transition (EndMT) are demonstrated to be mechanistically related to endothelial dysfunction. Mesenchymal stem cells (MSCs) have exhibited an extraordinary cytoprotective effect on cellular lipotoxicity and vasculopathy. However, the underlying mechanisms have not been clearly defined. In the present study, we investigated whether MSCs could ameliorate palmitic acid (PA)-induced endothelial lipotoxicity by reducing ER stress and EndMT. We observed that MSC cocultures substantially alleviated PA-induced lipotoxicity in human umbilical vein endothelial cells (HUVECs). MSCs were able to restore the cell viability, increase tubule formation and migration ability, and decrease inflammation response and lipid deposition. Furthermore, PA caused endothelial-to-mesenchymal transition in HUVECs, which was abrogated by MSCs possibly through inhibiting ER stress. In addition, PA stimulated MSCs to secrete more stanniocalcin-1 (STC-1). Knocking down of STC-1 in MSCs attenuated their effects on PA-induced lipotoxicity in HUVECs. In vivo, MSC transplantation alleviated dyslipidemia and endothelial dysfunction in high-fat diet-fed Sprague-Dawley rats. MSC-treated rats showed reduced expressions of ER stress-related genes in aortas and suppressed expressions of EndMT-related proteins in rat aortic endothelial cells. Overall, our findings indicated that MSCs were able to attenuate endothelial lipotoxicity through inhibiting ER stress and EndMT, in which STC-1 secreted from MSCs may play a critical role.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Ácido Palmítico/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Endotélio Vascular/fisiologia , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Recém-Nascido , Masculino , Células-Tronco Mesenquimais/citologia , Gravidez , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
12.
Clin Sci (Lond) ; 133(15): 1759-1777, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31383716

RESUMO

Macrophage polarization toward the M1 phenotype and its subsequent inflammatory response have been implicated in the progression of diabetic complications. Despite adverse consequences of autophagy impairment on macrophage inflammation, the regulation of macrophage autophagy under hyperglycemic conditions is incompletely understood. Here, we report that the autophagy-lysosome system and mitochondrial function are impaired in streptozotocin (STZ)-induced diabetic mice and high glucose (HG)-stimulated RAW 264.7 cells. Mitochondrial dysfunction promotes reactive oxygen species (ROS) production and blocks autophagic flux by impairing lysosome function in macrophages under hyperglycemic conditions. Conversely, inhibition of mitochondrial ROS by Mito-TEMPO prevents HG-induced M1 macrophage polarization, and its effect is offset by blocking autophagic flux. The role of mitochondrial ROS in lysosome dysfunction and M1 macrophage polarization is also demonstrated in mitochondrial complex I defective RAW 264.7 cells induced by silencing NADH:ubiquinone oxidoreductase subunit-S4 (Ndufs4). These findings prove that mitochondrial ROS plays a key role in promoting macrophage polarization to inflammatory phenotype by impairing autophagy-lysosome system, which might provide clue to a novel treatment for diabetic complications.


Assuntos
Autofagia , Polaridade Celular , Diabetes Mellitus Experimental/fisiopatologia , Lisossomos/metabolismo , Macrófagos/citologia , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Humanos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7
13.
Neurochem Res ; 43(10): 2016, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30171421

RESUMO

The order of corresponding author was inadvertently published. Hence, the first and the second corresponding authors should be Min Zhang (hebmuzhangmin@163.com) and Jing-Ge Zhang (zhangjg001@163.com).

14.
Neurochem Res ; 43(9): 1779-1790, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29995175

RESUMO

Previous studies have shown that intermittent hypobaric hypoxia (IH) preconditioning protected neurons survival from brain ischemia. However, the mechanism remains to be elucidated. The present study explored the role of nitric oxide (NO) in the process by measuring the expression of NO synthase (NOS) and NO levels. Male Wistar rats (100) were randomly assigned into four groups: sham group, IH + sham group, ischemia group and IH + ischemia group. Rats for IH preconditioning were exposed to hypobaric hypoxia mimicking 5000 m high-altitude (PB = 404 mmHg, PO2 = 84 mmHg) 6 h/day, once daily for 28 days. Global brain ischemia was established by four-vessel occlusion that has been created by Pulsinelli. Rats were sacrificed at 7th day after the ischemia for neuropathological evaluation by thionin stain. In addition, the expression of neuronal NOS (nNOS), inducible NOS (iNOS), and NO content in the hippocampal CA1 subfield were measured at 2nd day and 7th day after the ischemia. Results revealed that global brain ischemia engendered delayed neuronal death (DND), both nNOS and iNOS expression up-regulated, and NO content increased in the hippocampal CA1 subfield. IH preconditioning reduced neuronal injury induced by the ischemia, and prevented the up-regulation of NOS expression and NO production. In addition, L-NAME + ischemia group was designed to detect whether depressing NO production could alleviate the DND. Pre-administration of L-NAME alleviated DND induced by the ischemia. These results suggest that IH preconditioning plays a protective role by inhibiting the over expression of NOS and NO content after brain ischemia.


Assuntos
Isquemia Encefálica/metabolismo , Região CA1 Hipocampal/metabolismo , Hipóxia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Animais , Isquemia Encefálica/patologia , Região CA1 Hipocampal/patologia , Hipóxia/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar
15.
Can J Physiol Pharmacol ; 96(8): 807-814, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29400080

RESUMO

Many studies have demonstrated that chronic intermittent hypobaric hypoxia (CIHH) can reduce blood pressure in spontaneously hypertensive rats and renovascular hypertensive (RVH) rats in which endothelial dysfunction is determined as a critical factor. However, whether CIHH can regulate vasodilation of the aorta in RVH rats remains unknown. The purpose of this study was to investigate the effect of CIHH on impaired relaxation of the aorta in the 2-kidney, 1-clip (2K1C) RVH rat model. The results showed CIHH improved the impaired endothelium-dependent relaxation in the 2K1C rat aorta. The endothelial dysfunction was prevented by the p38 antagonist SB203580, but not by the ERK1/2 antagonist PD98059 or JNK antagonist SP600125. Furthermore, the expression of p-eNOS, HIF-1α, and HIF-2α increased while that of p-p38 and BMP-4 decreased in CIHH-treated aortas from 2K1C rats. Finally, the p-eNOS expression was upregulated and the p-p38 expression was downregulated by pre-incubation of SB203580 or the BMP-4 antagonist Noggin with the aorta. CIHH ameliorated the impairment of endothelium-dependent relaxation through upregulating the expression of p-eNOS, which may be mediated by the inhibition of BMP-4/p-p38 MAPK, and upregulating the expression of HIFs in the 2K1C rat aorta.


Assuntos
Aorta/patologia , Hipertensão/patologia , Hipóxia/patologia , Rim/patologia , Instrumentos Cirúrgicos , Acetilcolina/farmacologia , Animais , Antracenos/farmacologia , Antracenos/uso terapêutico , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Proteína Morfogenética Óssea 4/metabolismo , Proteínas de Transporte/farmacologia , Doença Crônica , Modelos Animais de Doenças , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipóxia/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Técnicas In Vitro , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Nitroprussiato/farmacologia , Fosforilação/efeitos dos fármacos , Piridinas/farmacologia , Piridinas/uso terapêutico , Ratos Sprague-Dawley , Sístole , Vasodilatação/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
J Cell Mol Med ; 21(10): 2553-2562, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28402018

RESUMO

Hyperuricemia is an important risk factor for cardiovascular and renal diseases. Phloretin had shown antioxidant and anti-inflammatory properties, but its role in endothelial injury is rarely reported. In this study, we aimed to investigate the protective effect of phloretin on UA-induced injury in human umbilical vein endothelial cells. The effects of UA and phloretin on cell viability, inflammation, THP-1 monocyte adhesion, endothelial cell tube formation, GLUT9 expression and UA uptake in human umbilical vein endothelial cells were evaluated. The changes of nuclear factor-kappa B/extracellular regulated protein kinases signalling were also analysed. Our results showed that UA reduced cell viability and tube formation, and increased inflammation and monocytes adhesion in human umbilical vein endothelial cells in a dose-dependent manner. In contrast, phloretin significantly attenuated pro-inflammatory factors expression and endothelial injury induced by UA. Phloretin inhibited the activation of extracellular regulated protein kinases/nuclear factor-kappa B pathway, and reduced GLUT9 and it mediated UA uptake in human umbilical vein endothelial cells. These results indicated that phloretin attenuated UA-induced endothelial injury via a synergic mechanism including direct anti-inflammatory effect and lowering cellular UA uptake. Our study suggested that phloretin might be a promising therapy for hyperuricemia-related cardiovascular diseases.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Inflamação/prevenção & controle , Floretina/farmacologia , Ácido Úrico/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células Cultivadas , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Proteínas Facilitadoras de Transporte de Glucose/genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hiperuricemia/fisiopatologia , Inflamação/metabolismo , Inflamação/fisiopatologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , NF-kappa B/metabolismo , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Ácido Úrico/farmacocinética
17.
Clin Sci (Lond) ; 130(23): 2181-2198, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27613156

RESUMO

Vasculopathy is a major complication of diabetes. Impaired mitochondrial bioenergetics and biogenesis due to oxidative stress are a critical causal factor for diabetic endothelial dysfunction. Sirt1, an NAD+-dependent enzyme, is known to play an important protective role through deacetylation of many substrates involved in oxidative phosphorylation and reactive oxygen species generation. Mesenchymal stem cell-conditioned medium (MSC-CM) has emerged as a promising cell-free therapy due to the trophic actions of mesenchymal stem cell (MSC)-secreted molecules. In the present study, we investigated the therapeutic potential of MSC-CMs in diabetic endothelial dysfunction, focusing on the Sirt1 signalling pathway and the relevance to mitochondrial function. We found that high glucose-stimulated MSC-CM attenuated several glucotoxicity-induced processes, oxidative stress and apoptosis of endothelial cells of the human umbilical vein. MSC-CM perfusion in diabetic rats ameliorated compromised aortic vasodilatation and alleviated oxidative stress in aortas. We further demonstrated that these effects were dependent on improved mitochondrial function and up-regulation of Sirt1 expression. MSC-CMs activated the phosphorylation of phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt), leading to direct interaction between Akt and Sirt1, and subsequently enhanced Sirt1 expression. In addition, both MSC-CM and Sirt1 activation could increase the expression of peroxisome proliferator-activated receptor γ co-activator-1α (PGC-1α), as well as increase the mRNA expression of its downstream, mitochondrial, biogenesis-related genes. This indirect regulation was mediated by activation of AMP-activated protein kinase (AMPK). Overall our findings indicated that MSC-CM had protective effects on endothelial cells, with respect to glucotoxicity, by ameliorating mitochondrial dysfunction via the PI3K/Akt/Sirt1 pathway, and Sirt1 potentiated mitochondrial biogenesis, through the Sirt1/AMPK/PGC-1α pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Meios de Cultivo Condicionados/farmacologia , Diabetes Mellitus Experimental/terapia , Células-Tronco Mesenquimais/metabolismo , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 1/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Apoptose , Meios de Cultivo Condicionados/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Glucose/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Mitocôndrias/genética , Estresse Oxidativo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Sirtuína 1/genética
18.
Int J Mol Sci ; 17(4): 483, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27043548

RESUMO

Glucolipotoxicity is one of the critical causal factors of diabetic complications. Whether mesenchymal stem cells (MSCs) have effects on glucolipotoxicity in human umbilical vein endothelial cells (HUVECs) and mechanisms involved are unclear. Thirty mM glucose plus 100 µM palmitic acid was used to induce glucolipotoxicity in HUVECs. MSCs and HUVECs were co-cultured at the ratio of 1:5 via Transwell system. The mRNA expressions of inflammatory factors were detected by RT-qPCR. The productions of reactive oxygen species (ROS), cell cycle and apoptosis were analyzed by flow cytometry. The tumor necrosis factor-α stimulated protein 6 (TSG-6) was knockdown in MSCs by RNA interference. High glucose and palmitic acid remarkably impaired cell viability and tube formation capacity, as well as increased the mRNA expression of inflammatory factors, ROS levels, and cell apoptosis in HUVECs. MSC co-cultivation ameliorated these detrimental effects in HUVECs, but no effect on ROS production. Moreover, TSG-6 was dramatically up-regulated by high glucose and fatty acid stimulation in both MSCs and HUVECs. TSG-6 knockdown partially abolished the protection mediated by MSCs. MSCs had protective effects on high glucose and palmitic acid induced glucolipotoxicity in HUVECs, and TSG-6 secreted by MSCs was likely to play an important role in this process.


Assuntos
Apoptose/efeitos dos fármacos , Glucose/toxicidade , Células-Tronco Mesenquimais/citologia , Ácido Palmítico/toxicidade , Moléculas de Adesão Celular/antagonistas & inibidores , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quimiocinas/genética , Quimiocinas/metabolismo , Técnicas de Cocultura , Citocinas/genética , Citocinas/metabolismo , Citometria de Fluxo , Células Endoteliais da Veia Umbilical Humana , Humanos , Células-Tronco Mesenquimais/metabolismo , Microscopia de Fluorescência , NF-kappa B/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima/efeitos dos fármacos
19.
Mol Neurobiol ; 61(4): 2411-2429, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37884768

RESUMO

The neurological injury and repair mechanisms after ischemic stroke are complex. The inflammatory response is present throughout stroke onset and functional recovery, in which CD4 + T helper(Th) cells play a non-negligible role. Th17 cells, differentiated from CD4 + Th cells, are regulated by various extracellular signals, transcription factors, RNA, and post-translational modifications. Th17 cells specifically produce interleukin-17A(IL-17A), which has been reported to have pro-inflammatory effects in many studies. Recently, experimental researches showed that Th17 cells and IL-17A play an important role in promoting stroke pathogenesis (atherosclerosis), inducing secondary damage after stroke, and regulating post-stroke repair. This makes Th17 and IL-17A a possible target for the treatment of stroke. In this paper, we review the mechanism of action of Th17 cells and IL-17A in ischemic stroke and the progress of research on targeted therapy.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Interleucina-17 , Células Th17/patologia , AVC Isquêmico/patologia , Acidente Vascular Cerebral/patologia , Diferenciação Celular , Células Th1
20.
Sci Adv ; 10(21): eado1755, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38787946

RESUMO

State-of-the-art technology for cyclohexanone oxime production typically demands elevated temperature and pressure, along with the utilization of expensive hydroxylamine sulfate or oxidants. Here, we propose an electrochemistry-assisted cascade strategy for the efficient cyclohexanone ammoximation under ambient conditions by using in situ cathode-generated green oxidants of reactive oxygen species (ROS) such as OOH* and H2O2. This electrochemical reaction can take place at the cathode, achieving over 95% yield, 99% selectivity of cyclohexanone oxime, and an electron-to-oxime (ETO) efficiency of 96%. Mechanistic analysis reveals that, in addition to the direct ammoximation by in situ-generated OOH* by electrocatalytic ORR, Ti-MOR also play a major role in capturing OOH* directly and converting the in situ-generated H2O2 to OOH*, thus accelerating the ORR-coupled cascade production of cyclohexanone oxime. This work paves a mild, economical, and sustainable energy-efficient electrocatalytic route for the oxime production using oxygen, ammonium bicarbonate, and cyclohexanone.

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