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1.
Sensors (Basel) ; 24(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38475143

RESUMO

Overlapped Time Domain Multiplexing (OvTDM) is a high-rate transmission technology that employs the idea of superposition coded modulation (SCM) scheme for signal generation, aiming to achieve maximum channel capacity sharing. Meanwhile, it is also widely considered as a promising technique toward physical layer security. As a main drawback of such system, a high peak-to-average power ratio (PAPR) issue in this system, arising from multi-layer superposition, can be addressed through intentional clipping. However, the detection at the receiver side is vulnerable to nonlinear distortion caused by clipping, which can degrade the performance. To mitigate this distortion, this paper proposed an iterative scheme for estimating and partially canceling clipping distortion at the receiver. We managed to mitigate the impact of clipping noise as much as possible and minimize the cost of optimizing PAPR, thereby improving the transmission performance of OvTDM in the context of amplitude clipping.

2.
J Cell Physiol ; 238(3): 659-669, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36780378

RESUMO

Hepatic ischemia-reperfusion (I/R) injury commonly occurs during liver surgery. Exosomes from adipose-derived stem cells (ADSCs-exo) induce a hepatoprotective effect during hepatic I/R injury. This study aimed to investigate the possible mechanism by which ADSCs-exo attenuates hepatic I/R injury in rats. Rats were randomly divided into four groups: Sham, I30R + PH, ADSCs, and ADSCs-exo groups. Liver tissues were collected immediately after 24 h of reperfusion for further analyses. The content of inflammatory factors in liver tissue was detected using enzyme-linked immunosorbent assay. The pathological changes in liver tissue were analyzed using HE staining. Transmission electron microscopy was used to visualize the ultrastructural changes of hepatocytes. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were used to detect the expression of endoplasmic reticulum stress (ERS)-related genes and proteins. Liver histomorphology and hepatocyte ultrastructure changes improved after ADSCs-exo treatment. Moreover, ADSCs-exo treatment significantly downregulated tumor necrosis factor-α, interleukin-1ß (IL-1ß), and IL-6 levels while upregulating IL-10 levels. Western blot analysis suggested that the protein expressions of GRP78, p-PERK, p-eIF2α, p-IRE1α, XBP1s, ATF-6, ATF-4, CHOP, p-JNK, cleaved-Caspase-3, cleaved Caspase-9, and cleaved Caspase-12 significantly decreased after ADSCs-exo treatment. RT-qPCR results demonstrated that mRNA expression of GRP78, IRE1α, XBP1, ATF-6, ATF-4, CHOP, JNK, Caspase-3, Caspase-9, and Caspase-12 markedly reduced after ADSCs-exo treatment. In conclusion, ADSCs-exo protects against hepatic I/R injury after hepatectomy by inhibiting ERS and inflammation. Therefore, ADSCs-exo can be considered as a viable option for the treatment of hepatic I/R injury.


Assuntos
Tecido Adiposo , Estresse do Retículo Endoplasmático , Exossomos , Hepatectomia , Inflamação , Fígado , Traumatismo por Reperfusão , Células-Tronco , Animais , Ratos , Inflamação/patologia , Inflamação/prevenção & controle , Fígado/metabolismo , Fígado/patologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Exossomos/metabolismo , Células-Tronco/metabolismo , Tecido Adiposo/citologia , Caspases/metabolismo , Interleucinas/metabolismo
3.
Inorg Chem ; 62(37): 15206-15214, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37665686

RESUMO

Through reasonable selections of raw materials and experimental methods, a new rare-earth borate fluoride K11Sc5(B5O10)4F6 is synthesized successfully by the high-temperature solution method in a closed system, which is the first noncentrosymmetric scandium borate fluoride. It crystallizes in the Fdd2 space group of the orthorhombic crystal system and features an extremely complicated structure constructed by the fundamental building blocks [B5O10] units, Sc-based, and K-based polyhedra. To our knowledge, K11Sc5(B5O10)4F6 is the only rare-earth borate that contains two kinds of [B5O10] groups and crystallizes in the Fdd2 space group, enriching the structural chemistry of rare-earth borates and rare-earth borate fluorides. Additionally, it is discussed in detail how F can significantly improve performance by modifying the modules in a comparison of structures. Discussion on rational synthetic conditions is instructive for obtaining rare-earth borate fluorides. Furthermore, a short cutoff edge (<190 nm) is experimentally confirmed, indicating the potential application of K11Sc5(B5O10)4F6 in ultraviolet/deep-ultraviolet regions.

4.
J Cell Mol Med ; 25(21): 10152-10163, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34609057

RESUMO

Hepatic ischaemia reperfusion injury (HIRI) is a major factor leading to liver dysfunction after liver resection and liver transplantation. Adipose-derived mesenchymal stem cells (ADSCs) have potential therapeutic effects on HIRI. Exosomes derived from ADSCs (ADSCs-exo) have been widely studied as an alternative of ADSCs therapy. Thus, the aim of this study was to evaluate the potential protective effect and related mechanism of ADSCs-exo on HIRI subsequent to hepatectomy. Rats were randomly divided into four groups: Sham, I30R+PH, ADSCs and ADSCs-exo group. After 24 h of reperfusion, liver and serum of the rats were immediately collected. ADSCs-exo improved liver function, inhibited oxidative stress and reduced apoptosis of hepatocytes in HIRI subsequent to hepatectomy in rats. ADSCs-exo significantly promoted the recovery of mitochondrial function, markedly increased the content of ATP in the liver tissue, and improved the ultrastructure of mitochondria in hepatocytes. Moreover, ADSCs-exo significantly increased the expression of OPA-1, MFN-1 and MFN-2 proteins related to mitochondrial fusion, while DRP-1 and Fis-1 mRNA and protein expression associated with mitochondrial fission were significantly decreased after the treatment with ADSCs-exo. In addition, ADSCs-exo significantly increased the expression of PGC-1α, NRF-1 and TFAM genes and proteins related to mitochondrial biogenesis. ADSCs-exo improves liver function induced by HIRI subsequent to hepatectomy in rats and maintains mitochondrial homeostasis by inhibiting mitochondrial fission, promoting mitochondrial fusion and promoting mitochondrial biogenesis. Therefore, ADSCs-exo may be considered as a potential promising alternative to ADSCs in the treatment of HIRI subsequent to hepatectomy.


Assuntos
Exossomos/metabolismo , Fígado/irrigação sanguínea , Fígado/metabolismo , Células-Tronco Mesenquimais/metabolismo , Dinâmica Mitocondrial , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Trifosfato de Adenosina/metabolismo , Tecido Adiposo/citologia , Animais , Apoptose , Biomarcadores , Hepatectomia , Hepatócitos/metabolismo , Imunofenotipagem , Fígado/patologia , Testes de Função Hepática , Estresse Oxidativo , Ratos , Traumatismo por Reperfusão/patologia
5.
Hepatobiliary Pancreat Dis Int ; 18(1): 48-61, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30573299

RESUMO

BACKGROUND: Hydrogen-rich saline (HRS) has antioxidative, anti-inflammatory and anti-apoptotic properties. We investigated the effects of hydrogen on hepatic ischemia-reperfusion (I/R) and laparoscopic hepatectomy in swine. METHODS: Twenty-one healthy Bama miniature pigs were randomly divided into the sham group, ischemia-reperfusion injury (IRI) group, HRS-5 (5 mL/kg) group, and HRS-10 (10 mL/kg) group. HRS was injected through the portal vein 10 min before reperfusion and at postoperative day 1, 2 and 3. The roles of HRS on oxidative stress, inflammatory response and liver regeneration were studied. RESULTS: Compared with the IRI group, HRS treatment attenuated oxidative stress by increasing catalase activity and reducing myeloperoxidase. White blood cells in the HRS-10 group were reduced compared with the IRI group (P < 0.01). In the HRS-10 group, interleukin-1 beta, interleukin-6 and tumor necrosis factor alpha, C-reactive protein and cortisol were downregulated, whereas interleukin-10 was upregulated. In addition, HRS attenuated endothelial cell injury and promoted the secretion of angiogenic cytokines, including vascular endothelial growth factor, angiopoietin-1 and angiopoietin-2. HRS elevated the levels of hepatocyte growth factor, Cyclin D1, proliferating cell nuclear antigen, Ki-67 and reduced the secretion of transforming growth factor-beta. CONCLUSIONS: HRS treatment may exert a protective effect against I/R and hepatectomy-induced hepatic damage by reducing oxidative stress, suppressing the inflammatory response and promoting liver regeneration.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Hepatectomia/efeitos adversos , Laparoscopia/efeitos adversos , Hepatopatias/prevenção & controle , Fígado/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Solução Salina/farmacologia , Proteínas Angiogênicas/metabolismo , Animais , Catalase/metabolismo , Proteínas de Ciclo Celular/metabolismo , Modelos Animais de Doenças , Hepatectomia/métodos , Mediadores da Inflamação/metabolismo , Laparoscopia/métodos , Fígado/metabolismo , Fígado/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Regeneração Hepática/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Suínos , Porco Miniatura , Fatores de Tempo
6.
Mol Ther ; 25(5): 1248-1258, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28366766

RESUMO

Chimeric antigen receptor T (CAR-T) cells have shown promising efficacy in treatment of hematological malignancies, but its applications in solid tumors need further exploration. In this study, we investigated CAR-T therapy targeting carcino-embryonic antigen (CEA)-positive colorectal cancer (CRC) patients with metastases to evaluate its safety and efficacy. Five escalating dose levels (DLs) (1 × 105 to 1 × 108/CAR+/kg cells) of CAR-T were applied in 10 CRC patients. Our data showed that severe adverse events related to CAR-T therapy were not observed. Of the 10 patients, 7 patients who experienced progressive disease (PD) in previous treatments had stable disease after CAR-T therapy. Two patients remained with stable disease for more than 30 weeks, and two patients showed tumor shrinkage by positron emission tomography (PET)/computed tomography (CT) and MRI analysis, respectively. Decline of serum CEA level was apparent in most patients even in long-term observation. Furthermore, we observed persistence of CAR-T cells in peripheral blood of patients receiving high doses of CAR-T therapy. Importantly, we observed CAR-T cell proliferation especially in patients after a second CAR-T therapy. Taken together, we demonstrated that CEA CAR-T cell therapy was well tolerated in CEA+ CRC patients even in high doses, and some efficacy was observed in most of the treated patients.


Assuntos
Adenocarcinoma/terapia , Antígeno Carcinoembrionário/genética , Neoplasias Colorretais/terapia , Neoplasias Hepáticas/terapia , Recidiva Local de Neoplasia/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/imunologia , Adenocarcinoma/secundário , Idoso , Antígeno Carcinoembrionário/imunologia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Citotoxicidade Imunológica , Relação Dose-Resposta Imunológica , Feminino , Expressão Gênica , Humanos , Imunoterapia Adotiva , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário , Ativação Linfocitária , Depleção Linfocítica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/imunologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Engenharia de Proteínas , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/citologia , Linfócitos T/transplante
7.
Hepatology ; 64(3): 814-27, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27312708

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is a highly aggressive liver tumor containing cancer stem cells (CSCs), which participate in tumor invasion, therapeutic resistance, and tumor relapse leading to poor outcome and limited therapeutic options. Histone deacetylatase sirtuin 1 (SIRT1) has been shown to be up-regulated in human cancers; however, its role in liver CSCs is unknown. In this study, we explored the biological functions of SIRT1 in liver CSCs. Our data show that SIRT1 is highly expressed in liver CSCs and decreases during differentiation. In addition, high levels of SIRT1 predict a decreased probability of survival in patients with HCC. SIRT1 is responsible for the maintenance of self-renewal and tumorigenicity of liver CSCs, and overexpression of exogenous SIRT1 can restore self-renewal of non-CSCs. We demonstrated that SOX2 is a main downstream regulator of SIRT1-mediated self-renewal and tumorigenicity potential of liver CSCs. Mechanistically, SIRT1 regulates transcription of the SOX2 gene by way of chromatin-based epigenetic changes, which are dependent on DNA methylation. This effect is achieved by alternation of histone modification and interaction with DNA methyltransferase 3A, resulting in hypermethylation of SOX2 promoter. Furthermore, we demonstrated that insulin growth factor signaling plays an important role in maintaining SIRT1 expression through increased SIRT1 protein stability. CONCLUSIONS: These findings highlight the importance of SIRT1 in the biology of liver CSCs and suggest that SIRT1 may serve as a molecular target for HCC therapy. (Hepatology 2016;64:814-827).


Assuntos
Carcinoma Hepatocelular/metabolismo , Autorrenovação Celular , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Sirtuína 1/metabolismo , Animais , DNA Metiltransferase 3A , Epigênese Genética , Feminino , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Somatomedinas/metabolismo
8.
Hepatology ; 56(3): 1004-14, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22473773

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) exhibits cellular heterogeneity and embryonic stem-cell-related genes are preferentially overexpressed in a fraction of cancer cells of poorly differentiated tumors. However, it is not known whether or how these cancer cells contribute to tumor initiation and progression. Here, our data showed that increased expression of pluripotency transcription factor Nanog in cancer cells correlates with a worse clinical outcome in HCC. Using the Nanog promoter as a reporter system, we could successfully isolate a small subpopulation of Nanog-positive cells. We demonstrate that Nanog-positive cells exhibited enhanced ability of self-renewal, clonogenicity, and initiation of tumors, which are consistent with crucial hallmarks in the definition of cancer stem cells (CSCs). Nanog(Pos) CSCs could differentiate into mature cancer cells in in vitro and in vivo conditions. In addition, we found that Nanog(Pos) CSCs exhibited resistance to therapeutic agents (e.g., sorafenib and cisplatin) and have a high capacity for tumor invasion and metastasis. Knock-down expression of Nanog in Nanog(Pos) CSCs could decrease self-renewal accompanied with decreased expression of stem-cell-related genes and increased expression of mature hepatocyte-related genes. Overexpression of Nanog in Nanog(Neg) cells could restore self-renewal. Furthermore, we found that insulin-like growth factor (IGF)2 and IGF receptor (IGF1R) were up-regulated in Nanog(Pos) CSCs. Knock-down expression of Nanog in Nanog(Pos) CSCs inhibited the expression of IGF1R, and overexpression of Nanog in Nanog(Neg) cells increased the expression of IGF1R. A specific inhibitor of IGF1R signaling could significantly inhibit self-renewal and Nanog expression, indicating that IGF1R signaling participated in Nanog-mediated self-renewal. CONCLUSION: These data indicate that Nanog could be a novel biomarker for CSCs in HCC, and that Nanog could play a crucial role in maintaining the self-renewal of CSCs through the IGF1R-signaling pathway.


Assuntos
Carcinoma Hepatocelular/patologia , Proteínas de Homeodomínio/fisiologia , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/fisiologia , Receptor IGF Tipo 1/fisiologia , Proteínas de Homeodomínio/biossíntese , Humanos , Proteína Homeobox Nanog , Transdução de Sinais
9.
Dalton Trans ; 52(47): 18027-18034, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37987555

RESUMO

Three Mg-containing borates were obtained by high-temperature spontaneous crystallization. In the (A2O)- or (A2O-MO)-MgO-B2O3 system (A is alkali metal and M is alkaline-earth metal) reported in the ICSD, Li4Mg3SrB12O24 is the first compound that contains one-dimensional infinite anionic chains, and the two examples of the isostructural A2Mg3B16O28 (A = Rb, Cs) exhibit a two-dimensional infinite bilayer structure for the first time, which contributes to the enrichment of the structural chemistry of Mg-containing borates. Besides, the results of comparison and analysis in this system clearly show that Mg not only affects the anionic frameworks of borates to produce low-dimensional structures but, together with the ratio of Ncation/NB, is responsible for the dimensionalities of the anionic frameworks in borates. The optical properties of the three compounds also show that they all have short cutoff edges, and Cs2Mg3B16O28, in particular, could reach the deep-ultraviolet region (<200 nm).

10.
Front Immunol ; 14: 1182409, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304295

RESUMO

Introduction: Chimeric antigen receptor T (CAR-T) cell therapy presents a promising treatment option for various cancers, including solid tumors. Carcinoembryonic antigen (CEA) is an attractive target due to its high expression in many tumors, particularly gastrointestinal cancers, while limited expression in normal adult tissues. In our previous clinical study, we reported a 70% disease control rate with no severe side effects using a humanized CEA-targeting CAR-T cell. However, the selection of the appropriate single-chain variable fragment (scFv) significantly affects the therapeutic efficacy of CAR-T cells by defining their specific behavior towards the target antigen. Therefore, this study aimed to identify the optimal scFv and investigate its biological functions to further optimize the therapeutic potential of CAR-T cells targeting CEA-positive carcinoma. Methods: We screened four reported humanized or fully human anti-CEA antibodies (M5A, hMN-14, BW431/26, and C2-45), and inserted them into a 3rd-generation CAR structure. We purified the scFvs and measured the affinity. We monitored CAR-T cell phenotype and scFv binding stability to CEA antigen through flow cytometry. We performed repeated CEA antigen stimulation assays to compare the proliferation potential and response of the four CAR-T cells, then further evaluated the anti-tumor efficacy of CAR-T cells ex vivo and in vivo. Results: M5A and hMN-14 CARs displayed higher affinity and more stable CEA binding ability than BW431/26 and C2-45 CARs. During CAR-T cell production culture, hMN-14 CAR-T cells exhibit a larger proportion of memory-like T cells, while M5A CAR-T cells showed a more differentiated phenotype, suggesting a greater tonic signal of M5A scFv. M5A, hMN-14, and BW431/26 CAR-T cells exhibited effective tumor cell lysis and IFN-γ release when cocultured with CEA-positive tumor cells in vitro, correlating with the abundance of CEA expression in target cells. While C2-45 resulted in almost no tumor lysis or IFN-γ release. In a repeat CEA antigen stimulation assay, M5A showed the best cell proliferation and cytokine secretion levels. In a mouse xenograft model, M5A CAR-T cells displayed better antitumor efficacy without preconditioning. Discussion: Our findings suggest that scFvs derived from different antibodies have distinctive characteristics, and stable expression and appropriate affinity are critical for robust antitumor efficacy. This study highlights the importance of selecting an optimal scFv in CAR-T cell design for effective CEA-targeted therapy. The identified optimal scFv, M5A, could be potentially applied in future clinical trials of CAR-T cell therapy targeting CEA-positive carcinoma.


Assuntos
Carcinoma , Receptores de Antígenos Quiméricos , Anticorpos de Cadeia Única , Adulto , Humanos , Animais , Camundongos , Anticorpos de Cadeia Única/genética , Receptores de Antígenos Quiméricos/genética , Anticorpos Monoclonais , Imunoterapia Adotiva
11.
Stem Cell Res Ther ; 13(1): 427, 2022 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987696

RESUMO

BACKGROUND: The therapeutic effects of adipose-derived mesenchymal stromal cells (ADSCs) may be mainly mediated by their paracrine effects. The ADSC-secretome can ameliorate hepatic ischemia-reperfusion injury (IRI). We explored the therapeutic effect of the ADSC-secretome from the perspective of excessive hepatocyte autophagy induced by hepatic IRI. METHODS: We established a miniature pig model of hepatic ischemia-reperfusion (I/R) and hepatectomy using a laparoscopic technique and transplanted ADSCs and the ADSC-secretome into the liver parenchyma immediately after surgery. Liver injury and hepatocyte autophagy were evaluated by histopathological examination and assessment of relevant cytokines and other factors. RESULTS: The results showed that the ADSC-secretome alleviated the pathological changes of liver tissue and the microstructural damage of hepatocytes after IRI. Moreover, the expression levels of autophagy-related markers including Beclin-1, ATG5, ATG12, and LC3II/LC3I decreased, whereas those of p62 increased during phagophore expansion. Furthermore, the expression levels of markers related to the autophagy inhibition pathway phosphatidylinositol-3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR), including PI3K, Akt, and mTOR, increased. CONCLUSION: The ADSC-secretome attenuates hepatic I/R and hepatectomy-induced liver damage by inhibiting autophagy, which is possibly mediated by activation of the PI3K/Akt/mTOR signaling pathway. In addition, there was no significant difference between ADSCs and the ADSC-secretome in the regulation of hepatocyte autophagy. Therefore, ADSCs may improve the excessive autophagy-induced injury of hepatocytes in hepatic I/R and hepatectomy through paracrine effect. Our findings provide new insight into the therapeutic potential of cell-free products, which could replace cell therapy in liver diseases.


Assuntos
Hepatopatias , Células-Tronco Mesenquimais , Traumatismo por Reperfusão , Animais , Autofagia , Hepatectomia , Isquemia/patologia , Fígado/metabolismo , Hepatopatias/patologia , Mamíferos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reperfusão , Traumatismo por Reperfusão/metabolismo , Secretoma , Suínos , Serina-Treonina Quinases TOR/metabolismo
12.
Life Sci ; 289: 120212, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34896163

RESUMO

AIMS: Hepatic ischemia reperfusion injury (HIRI) is associated with liver failure after liver transplantation and hepatectomy. Thus, this study aims to explore the effect of conditioned medium from adipose derived stem cells (ADSC-CM) on endoplasmic reticulum stress (ERS) and lipid metabolism after HIRI combined with hepatectomy in miniature pigs. MAIN METHODS: A model of HIRI combined with hepatectomy in miniature pigs was established. The expression of ERS-related proteins and lipid metabolism related genes, as well as triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL), very low density lipoprotein (VLDL) and acetyl-CoA carboxylase 1 (ACC1) level were measured in liver tissues. KEY FINDINGS: Both ADSCs and ADSC-CM could improve the damage in the ultrastructure of hepatocytes. ADSC-CM significantly decreased the protein expression of GRP78, ATF6, XBP1, p-eIF2α, ATF4, p-JNK and CHOP. Oil red O staining revealed that the degree of hepatocyte steatosis was also significantly reduced after treatment with ADSC-CM. In addition, ADSC-CM remarkably decreased TG, TC, HDL and ACC1 level in liver tissues, while enhanced VLDL content. Finally, SREBP1, SCAP, FASN, ACC1, HMGCR and HMGCS1 mRNA expression was also markedly downregulated in liver tissues. SIGNIFICANCE: Injection of ADSC-CM into the hepatic parenchymal could represent a novel cell-free therapeutic approach to improve HIRI combined with hepatectomy injury. The inhibition of ERS and the improvement of lipid metabolism in the hepatocytes might be a potential mechanism used by ADSC-CM to prevent liver injury from HIRI combined with hepatectomy.


Assuntos
Tecido Adiposo/metabolismo , Estresse do Retículo Endoplasmático , Hepatectomia , Metabolismo dos Lipídeos , Falência Hepática/metabolismo , Transplante de Fígado , Fígado/metabolismo , Células-Tronco Mesenquimais/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Meios de Cultivo Condicionados/farmacologia , Falência Hepática/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Suínos , Porco Miniatura
13.
Stem Cells Int ; 2021: 9969372, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34457008

RESUMO

Ischemia-reperfusion injury (IRI) is an inevitable complication of liver surgery and liver transplantation. Hepatocyte apoptosis plays a significant role in the pathological process of hepatic IRI. Adipose-derived stem cells (ADSCs) are known to repair and regenerate damaged tissues by producing bioactive factors, including cytokines, exosomes, and extracellular matrix components, which collectively form the secretome of these cells. The aim of this study was to assess the protective effects of the ADSCs secretome after liver ischemia-reperfusion combined with partial hepatectomy in miniature pigs. We successfully established laparoscopic liver ischemia-reperfusion with partial hepatectomy in miniature pigs and injected saline, DMEM, ADSC-secretome, and ADSCs directly into the liver parenchyma immediately afterwards. Both ADSCs and the ADSC-secretome improved the IR-induced ultrastructural changes in hepatocytes and significantly decreased the proportion of TUNEL-positive apoptotic cells along with caspase activity. Consistent with this, P53, Bax, Fas, and Fasl mRNA and protein levels were markedly decreased, while Bcl-2 was significantly increased in the animals treated with ADSCs and ADSC-secretome. Our findings indicate that ADSCs exert therapeutic effects in a paracrine manner through their secretome, which can be a viable alternative to cell-based regenerative therapies.

14.
Life Sci ; 285: 119986, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34592233

RESUMO

AIMS: Hepatic ischemia reperfusion injury (HIRI) is a complication of liver surgery and liver transplantation. Adipose-derived stem cells (ADSCs) can inhibit oxidative stress and inflammation through a paracrine effect. This study aimed to determine the optimal time window of ADSCs transplantation to restore liver function after HIRI. MAIN METHODS: A rat model of hepatic ischemia reperfusion combined with partial hepatectomy (HIR/PH) was established. The animals were injected intravenously with 2 × 106 rat ADSCs 2 h before, immediately after, or 6 h after surgery. Liver tissues and blood samples were collected for routine histological and biochemical assays. The molecular changes were analyzed by qRT-PCR and western blotting. KEY FINDINGS: ADSCs significantly improved liver tissue structure and decreased the levels of AST, ALT and ALP, which was indicative of functional recovery. In addition, transplantation of ADSCs immediately after operation decreased the levels of inflammation-related cytokines such as TNF-α, IL-1ß and IL-6, and significantly increased the activity of antioxidant enzymes. At the same time, the expression of MDA was decreased. Mechanistically, ADSCs activated the Keap1/Nrf2 pathway in the injured liver. Transplantation of ADSCs pre- and 6 h post-operation did not significantly affect some indices such as mRNA and protein expression of HO-1, and protein expression of NQO1. SIGNIFICANCE: Transplanting ADSCs immediately after surgery accelerated tissue repair and functional recovery of the liver by activating the Keap1/Nrf2 pathway, which inhibited hepatic inflammation and oxidative stress, and restored the hepatic microenvironment.


Assuntos
Hepatectomia/efeitos adversos , Regeneração Hepática , Transplante de Fígado/efeitos adversos , Fígado/irrigação sanguínea , Fígado/cirurgia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/cirurgia , Tecido Adiposo/citologia , Alanina Transaminase/metabolismo , Animais , Modelos Animais de Doenças , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fígado/enzimologia , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Fosfodiesterase I/metabolismo , Ratos , Ratos Sprague-Dawley , Transaminases/metabolismo
15.
Stem Cell Res Ther ; 12(1): 218, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33781342

RESUMO

BACKGROUND: Hepatic ischaemia-reperfusion injury (HIRI) is inevitable in complicated liver surgery and is a major factor leading to postoperative complications and liver dysfunction. Studies have shown that the paracrine mechanisms of stem cell may be essential to tissue repair and functional improvement after transplantation. However, the role of the adipose-derived mesenchymal stem cell secretome (ASC-secretome) in liver regeneration in large animals remains to be determined. METHODS: Twenty-four miniature pigs were subjected to laparoscopic liver ischaemia-reperfusion combined with partial hepatectomy and divided into the following four groups: the saline group, the DMEM group, the ASC group and the ASC-secretome group. Serum and liver tissue samples were collected before the operation and at 1, 3 and 7 days after the operation, and changes in tissue pathology, serum inflammation, liver function, angiogenesis-related factors and liver tissue regeneration-related genes and proteins were evaluated. RESULTS: Detailed histological analysis showed that ASCs and the ASC-secretome changed pathological damage to liver tissue after liver ischaemia-reperfusion combined with partial hepatectomy (1 and 3 days: p < 0.01). Compared with the saline and DMEM control groups, the ASC-secretome group had significantly reduced expression levels of ALP (1 and 3 days: p < 0.05), ALT (1 day: p < 0.01; 3 days: p < 0.05) and AST (1 and 3 days: p < 0.01), which promoted the recovery of liver function. Moreover, detection of the expression levels of TNF-α and IL-1ß (1 day: p < 0.01; 3 days: p < 0.05), IL-6 (1 and 3 days: p < 0.05) and IL-10 (1 and 3 days: p < 0.01) in serum confirmed that the ASC-secretome had obvious anti-inflammatory effects. In addition, the ASC-secretome increased the expression levels of ANG-1 (3 days: p < 0.01), ANG-2 (3 and 7 days: p < 0.01) and VEGF (1 and 7 days: p < 0.05; 3 days: p < 0.01) and promoted angiogenesis during liver regeneration. Moreover, it promoted the mRNA expression of HGF and Cyclin D1 (1 and 3 days: p < 0.01); increased the levels of p-STAT3 (1 and 3 days: p < 0.01), PCNA and Ki67 (1 and 3 days: p < 0.01; 7 days: p < 0.05); inhibited the negative feedback of SOCS3 (1 and 3 days: p < 0.01); and decreased the mRNA expression of TGF-ß (3 days: p < 0.01). The cytokines and growth factors detected in the ASC-secretome included TNF-α, IL-6, IL-1ß, ANG-1, ANG-2, VEGF and b-FGF. CONCLUSION: The ASC-secretome alleviates the inflammatory response induced by ischaemia-reperfusion combined with partial hepatectomy in miniature pigs and promotes liver regeneration.


Assuntos
Hepatopatias , Células-Tronco Mesenquimais , Tecido Adiposo , Animais , Hepatectomia , Isquemia , Fígado , Regeneração Hepática , Reperfusão , Suínos , Porco Miniatura
16.
Front Cell Dev Biol ; 8: 177, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32266259

RESUMO

Ischemia-reperfusion (IR) is an inevitable complication of liver surgery. Recent studies indicate a critical role of endoplasmic reticulum stress (ERS) in hepatic IR. Mesenchymal stem cells (MSCs) have proven to be an effective tool for tissue regeneration and treatment of various diseases, including that of the liver. However, the mechanisms underlying the therapeutic effects of stem cells on hepatic IR injury (IRI) are still poorly understood, especially in the context of ERS. In this study, we established a porcine model of hepatic IRI and partial hepatectomy, and transplanted the animals with adipose-derived mesenchymal stem cells (ADSCs) isolated from miniature pigs. ADSCs not only alleviated the pathological changes in the liver parenchyma following IRI, but also protected the resident hepatocytes from damage. Mechanistically, the ADSCs significantly downregulated ERS-related proteins, including GRP78, p-eIF2α, ATF6 and XBP1s, as well as the proteins involved in ERS-induced apoptosis like p-JNK, ATF4 and CHOP. Taken together, ADSCs can alleviate hepatic IRI by inhibiting ERS and its downstream apoptotic pathways in the hepatocytes, indicating its therapeutic potential in liver diseases.

17.
Clin Cancer Res ; 26(7): 1606-1615, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31732519

RESUMO

PURPOSE: Immunogenicity derived from the murine scFv, a major molecular compomemt of chimeric antigen receptors (CARs), may limit the persistence of CAR T cells, resulting in tumor relapse of patients in complete remission (CR). In this study, we developed a humanized anti-CD19 scFv CAR-T (hCAR-T) to treat patients with relapsed/refractory acute lymphoblastic leukemia (r/r ALL). PATIENTS AND METHODS: In this one-arm, open-labeled study, we infused the T cells modified with hCAR to patients with r/r ALL. Patients were evaluated with long-term follow-up for response and safety of the treatment. The study was registered at Clinicaltrials.gov (NCT02349698). RESULTS: Ten patients with r/r ALL were recruited for this study. All were response evaluable and all achieved CR; eight patients remained CR, and six were in CR for over 18 months without further treatment. A long-term persistence of hCAR T cells was observed in most of the patients. Among these patients, four of them with high tumor burden and rapidly progressive disease (median, 58%) experienced grade 3-4 cytokine release syndrome (CRS) and neurotoxicity. These severe CRSs were successfully controlled by tocilizumab, glucocorticoid, and plasma exchange. CONCLUSIONS: T cells expressing the humanized anti-CD19 scFv CARs exhibited sustained therapeutic efficacy in the treatment of r/r ALL. Low replase rate was associated with the long-term persistence of CAR T cells.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD19/imunologia , Imunoterapia Adotiva/métodos , Recidiva Local de Neoplasia/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos Quiméricos/uso terapêutico , Linfócitos T/imunologia , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Camundongos , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Segurança do Paciente , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Resultado do Tratamento , Adulto Jovem
18.
Stem Cells Int ; 2019: 2489584, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827526

RESUMO

AIM: To study the anti-inflammatory and liver regenerative effects of adipose-derived mesenchymal stem cells (ADSCs) on a porcine model of ischemia-reperfusion (IR) and hemihepatectomy. METHODS: Eighteen healthy Bama miniature pigs were randomly divided into the sham-operated (sham), untreated IR injury (IRI), and ADSC-transplanted (ADSC) groups. Hepatic IR was established by laparoscopic hemihepatectomy. ADSCs were transplanted directly into the liver parenchyma after the surgery. Hepatic inflammation and liver regeneration were evaluated by histopathological examination and assessment of relevant cytokines and other factors. RESULTS: ADSC transplantation successfully ameliorated the IRI-induced histopathological damage and the high levels of pro-inflammatory cytokines like IL-1ß, IL-6, and TNF-α. In addition, the ADSCs enhanced the expression of the anti-inflammatory IL-10, regenerative factors including HGF, Cyclin D1, and proliferating cell nuclear antigen (PCNA), and angiogenic factors like VEGF, ANG-1, and ANG-2. CONCLUSIONS: ADSCs attenuated the hepatic IRI-induced inflammatory response and promoted liver regeneration.

19.
J Vet Res ; 63(3): 447-455, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31572827

RESUMO

INTRODUCTION: The miniature pig possesses unmatched advantages as an animal model because of its high homology with humans. Our experiment aimed to build a chronic renal failure (CRF) model in pigs via laparoscopy. MATERIAL AND METHODS: Laparoscopic surgery was performed twice to build a CRF model. The first surgery was a left partial nephrectomy and the second was a right radical nephrectomy. Pigs were grouped by the total renal tissue to be resected: ⅔, ¾ or ⅚. Physiological parameters (rectal temperature and heart rate), haematological parameters (WBC and RBC) and renal function (serum creatinine - CR and blood urea nitrogen - BUN) were measured preoperatively and every week postoperatively. RESULTS: After renal resection the pigs manifested chronic renal failure. Heart rate and body temperature declined to varying degrees over 12 postoperative weeks. No significant difference was observed between the different groups. The result of renal function tests found that postoperative serum CR and BUN in all groups were continuously elevated, and the level of serum CR at two weeks post procedure differed very significantly from its preoperative value (P < 0.05). BUN was significantly elevated at one week (P < 0.05). The renal function decreased significantly faster in the ⅚ group than in the other two groups. The trend of renal function change was similar among groups, but progress was slower in the ⅔ and ¾ groups. CONCLUSION: ⅚ kidney resection was the optimal miniature pig model of CRF.

20.
Biomed Pharmacother ; 120: 109453, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31561069

RESUMO

AIM: To compare and evaluate the hepatoprotective effect of liver parenchyma injection of ADSCs and portal vein injection of HRS in laparoscopic hepatic ischemia reperfusion combined with hepatectomy injury in miniature pigs. METHODS: Eighteen miniature pigs were randomly assigned to IRI group, HRS group and ADSCs group. HRS was injected through the portal vein 10 min before reperfusion, 1 d, 2 d, and 3 d after surgery. ADSCs were injected into liver parenchyma after hepatectomy. The serum and liver tissue samples were collected at different time points (preoperative, and postoperative at 1 d, 3 d and 7 d). RESULTS: Compared with the IRI group, both ADSCs and HRS groups can promote liver function recovery, reduce oxidative stress, reduce inflammation, and promote liver regeneration. Compared with HRS, ALT and TBIL in ADSCs group were significantly decreased at 3 d, and AST was significantly reduced at 1 d. The activities of SOD and GSH-Px in ADSCs group were significantly higher than that in HRS group, but the MDA level in HRS group was markedly lower than that in ADSCs group at 1 d. IL-1ß was significantly lower in the ADSCs group than in the HRS group at 1 day after operation. The expressions of HGF and PCNA were significantly higher than that in the HRS group at 3 day after surgery. CONCLUSION: Our study has demonstrated that HRS and ADSCs have significant hepatoprotective effects in miniature pigs after HIRI and hepatectomy injury. However, liver parenchyma injection of ADSCs is more beneficial to the recovery of liver function than portal vein injection of HRS.


Assuntos
Hepatectomia , Hidrogênio/farmacologia , Regeneração Hepática/efeitos dos fármacos , Traumatismo por Reperfusão/metabolismo , Células-Tronco/metabolismo , Adipócitos/metabolismo , Animais , Apoptose , Inflamação/tratamento farmacológico , Fígado/efeitos dos fármacos , Testes de Função Hepática , Modelos Animais , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras , Traumatismo por Reperfusão/induzido quimicamente , Suínos
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