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1.
RSC Adv ; 14(27): 19400-19427, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38887636

RESUMO

Chicory (Cichorium endivia L. divaricatum) is a renowned medicinal plant traditionally used for various ailments, yet the pharmacological potential of its roots, particularly in terms of antitumor activity, remains elusive. In the present study, we explore, for the first time, the metabolomic profile of ethanolic extract from Cichorium endivia roots (CIR) and further unveil its antiproliferative potential. The untargeted phytochemical analysis UPLC/T-TOF-MS/MS identified 131 metabolites in the CIR extract, covering acids, amino acids, flavonoids, alkaloids, nucleotides, and carbohydrates. The antiproliferative activity of the CIR extract was tested in 14 cancer cell lines, revealing significant cytotoxicity (IC50: 2.85-29.15 µg mL-1) and a high selectivity index. Among the cells examined, the CIR extract recorded the most potent antiproliferative activity and selectivity toward HepG2 and Panc-1 cells, with an IC50 of 2.85 µg mL-1 and 3.86 µg mL-1, respectively, and SI > 10. Insights into the mode of action of the antiproliferative activity revealed that CIR extract induces cell arrest in the S phase while diminishing cell distribution in the G0/G1 and G2/M phases in HepG-2 and Panc-1 cells. Flow cytometric and RT-PCR analysis revealed that the CIR extract significantly triggers apoptosis and modulates the expression of pro-apoptotic and anti-apoptotic genes. Furthermore, the CIR extract exhibited a pronounced anti-inflammatory activity, as evidenced by down-regulating key cytokines in LPS-induced RAW 264.7 cells and selectively inhibiting the COX-2 enzyme. Finally, the CIR extract showed a robust total antioxidant capacity, together with potent free radicals and metal scavenging properties, highlighting its role in alleviating oxidative stress. Taken together, this study highlights the multifaceted therapeutic potential of CIR extract as a natural-based antitumor supplement.

2.
Front Physiol ; 14: 1183101, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37435300

RESUMO

Duchenne muscular dystrophy (DMD) is a severe, progressive, and ultimately fatal disease of skeletal muscle wasting, respiratory insufficiency, and cardiomyopathy. The identification of the dystrophin gene as central to DMD pathogenesis has led to the understanding of the muscle membrane and the proteins involved in membrane stability as the focal point of the disease. The lessons learned from decades of research in human genetics, biochemistry, and physiology have culminated in establishing the myriad functionalities of dystrophin in striated muscle biology. Here, we review the pathophysiological basis of DMD and discuss recent progress toward the development of therapeutic strategies for DMD that are currently close to or are in human clinical trials. The first section of the review focuses on DMD and the mechanisms contributing to membrane instability, inflammation, and fibrosis. The second section discusses therapeutic strategies currently used to treat DMD. This includes a focus on outlining the strengths and limitations of approaches directed at correcting the genetic defect through dystrophin gene replacement, modification, repair, and/or a range of dystrophin-independent approaches. The final section highlights the different therapeutic strategies for DMD currently in clinical trials.

3.
Exp Clin Transplant ; 21(5): 387-396, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37334686

RESUMO

Genetically engineered pigs with multiple gene deletions and insertions are predicted to extend porcine to human xenograft survival. Several genes have been successfully knocked out and inserted, yet more have failed to produce viable animals for unexplained reasons. The effects of gene editing on cellular homeostasis may be the cause of reduced embryo fitness, failed pregnancies, or poor piglet viability. The elements of cellular dysfunction such as endoplasmic reticulum stress and oxidative stress induced by gene editing may additively affect the quality of genetically engineered cells to be used for cloning. Evaluating the impact of each gene edit on cellular fitness for cloning will allow researchers to maintain the cellular homeostasis of engineered cells that were validated as candidates for cloning and the production of porcine organ donors.


Assuntos
Estresse do Retículo Endoplasmático , Estresse Oxidativo , Animais , Humanos , Suínos , Transplante Heterólogo , Animais Geneticamente Modificados , Homeostase
4.
Int J Mol Sci ; 23(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36555864

RESUMO

The cardiac sarcomere is a triumph of biological evolution wherein myriad contractile and regulatory proteins assemble into a quasi-crystalline lattice to serve as the central point upon which cardiac muscle contraction occurs. This review focuses on the many signaling components and mechanisms of regulation that impact cardiac sarcomere function. We highlight the roles of the thick and thin filament, both as necessary structural and regulatory building blocks of the sarcomere as well as targets of functionally impactful modifications. Currently, a new focus emerging in the field is inter-myofilament signaling, and we discuss here the important mediators of this mechanism, including myosin-binding protein C and titin. As the understanding of sarcomere signaling advances, so do the methods with which it is studied. This is reviewed here through discussion of recent live muscle systems in which the sarcomere can be studied under intact, physiologically relevant conditions.


Assuntos
Miocárdio , Sarcômeros , Sarcômeros/metabolismo , Miocárdio/metabolismo , Coração/fisiologia , Conectina/metabolismo , Miofibrilas/fisiologia , Contração Miocárdica/fisiologia
5.
Front Immunol ; 12: 730545, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566993

RESUMO

The human leukocyte antigen G1 (HLA-G1), a non-classical class I major histocompatibility complex (MHC-I) protein, is a potent immunomodulatory molecule at the maternal/fetal interface and other environments to regulate the cellular immune response. We created GGTA1-/HLAG1+ pigs to explore their use as organ and cell donors that may extend xenograft survival and function in both preclinical nonhuman primate (NHP) models and future clinical trials. In the present study, HLA-G1 was expressed from the porcine ROSA26 locus by homology directed repair (HDR) mediated knock-in (KI) with simultaneous deletion of α-1-3-galactotransferase gene (GGTA1; GTKO) using the clustered regularly interspersed palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) (CRISPR/Cas9) gene-editing system. GTKO/HLAG1+ pigs showing immune inhibitory functions were generated through somatic cell nuclear transfer (SCNT). The presence of HLA-G1 at the ROSA26 locus and the deletion of GGTA1 were confirmed by next generation sequencing (NGS) and Sanger's sequencing. Fibroblasts from piglets, biopsies from transplantable organs, and islets were positive for HLA-G1 expression by confocal microscopy, flow cytometry, or q-PCR. The expression of cell surface HLA-G1 molecule associated with endogenous ß2-microglobulin (ß2m) was confirmed by staining genetically engineered cells with fluorescently labeled recombinant ILT2 protein. Fibroblasts obtained from GTKO/HLAG1+ pigs were shown to modulate the immune response by lowering IFN-γ production by T cells and proliferation of CD4+ and CD8+ T cells, B cells and natural killer (NK) cells, as well as by augmenting phosphorylation of Src homology region 2 domain-containing phosphatase-2 (SHP-2), which plays a central role in immune suppression. Islets isolated from GTKO/HLA-G1+ genetically engineered pigs and transplanted into streptozotocin-diabetic nude mice restored normoglycemia, suggesting that the expression of HLA-G1 did not interfere with their ability to reverse diabetes. The findings presented here suggest that the HLA-G1+ transgene can be stably expressed from the ROSA26 locus of non-fetal maternal tissue at the cell surface. By providing an immunomodulatory signal, expression of HLA-G1+ may extend survival of porcine pancreatic islet and organ xenografts.


Assuntos
Fibroblastos/metabolismo , Galactosiltransferases/deficiência , Antígenos HLA-G/metabolismo , Células Matadoras Naturais/metabolismo , Linfócitos T/metabolismo , Animais , Animais Geneticamente Modificados , Linfócitos B/imunologia , Linfócitos B/metabolismo , Glicemia/imunologia , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Fibroblastos/imunologia , Galactosiltransferases/genética , Genótipo , Antígenos HLA-G/imunologia , Haplorrinos , Humanos , Interferon gama/metabolismo , Transplante das Ilhotas Pancreáticas , Células Matadoras Naturais/imunologia , Ativação Linfocitária , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos Nus , Fenótipo , Sus scrofa , Linfócitos T/imunologia , Doadores de Tecidos , Transplante Heterólogo
6.
Surg Open Sci ; 4: 26-31, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33937740

RESUMO

BACKGROUND: Genetically engineered porcine donors are a potential solution for the shortage of human organs for transplantation. Incompatibilities between humans and porcine donors are largely due to carbohydrate xenoantigens on the surface of porcine cells, provoking an immune response which leads to xenograft rejection. MATERIALS AND METHODS: Multiplex genetic knockout of GGTA1, ß4GalNT2, and CMAH is predicted to increase the rate of xenograft survival, as described previously for GGTA1. In this study, the clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats-associated protein 9 system was used to target genes relevant to xenotransplantation, and a method for highly efficient editing of multiple genes in primary porcine fibroblasts was described. RESULTS: Editing efficiencies greater than 85% were achieved for knockout of GGTA1, ß4GalNT2, and CMAH. CONCLUSION: The high-efficiency protocol presented here reduces scale and cost while accelerating the production of genetically engineered primary porcine fibroblast cells for in vitro studies and the production of animal models.

7.
Xenotransplantation ; 28(1): e12641, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32892439

RESUMO

INTRODUCTION: Macrophages contribute to xenograft rejection by direct cytotoxicity and by amplifying T cell-mediated immune responses. It has been shown that transgenic expression of hCD47 protects porcine cells from human macrophages by restoring the CD47-SIRPα self-recognition signal. It has also been reported that the long 3' untranslated region (3'UTR) of the hCD47 gene, which is missing from constructs previously used to make hCD47 transgenic pigs, is critical for efficient cell surface expression in human cells. The aim of this study was to investigate the impact of a modified form of the 3'UTR on the expression, localization, and function of hCD47 in transfected porcine cells. METHODS: hCD47 constructs with and without the modified 3'UTR were knocked into the GGTA1 locus in porcine fetal fibroblasts using CRISPR. Flow cytometry of the transfected cells was used to analyze hCD47 localization. Endoplasmic reticulum (ER), mitochondrial, and oxidative stress were examined by gene expression analysis and confocal microscopy. Phagocytosis of transfected cells by human macrophages was measured by flow cytometry, and stimulation of human/non-human (NHP) primate lymphocytes by the cells was examined using a PBMCs proliferation assay. RESULTS: Cells transfected with the construct lacking the 3'UTR (hCD47(3'UTR-)) exhibited predominantly intracellular expression of hCD47, and showed evidence of ER stress, dysregulated mitochondrial biogenesis, oxidative stress, and autophagy. Inclusion of the 3'UTR (hCD47(3'UTR+)) decreased intracellular expression of hCD47 by 36% and increased cell surface expression by 53%. This was associated with a significant reduction in cellular stress markers and a higher level of protection from phagocytosis by human macrophages. Furthermore, hCD47(3'UTR+) porcine cells stimulated significantly less proliferation of human/NHP T cells than hCD47(3'UTR-) cells. CONCLUSION: Our results suggest the potential benefits of using hCD47 constructs containing the 3'UTR to generate genetically engineered hCD47-expressing donor pigs.


Assuntos
Antígeno CD47/genética , Estresse do Retículo Endoplasmático , Fibroblastos , Fagocitose , Regiões 3' não Traduzidas , Animais , Animais Geneticamente Modificados , Humanos , Suínos , Transplante Heterólogo
8.
Res Vet Sci ; 128: 59-68, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31722267

RESUMO

Handmade cloning is a zona-free nuclear transfer approach and an economical, efficient, and simple micromanipulation-free alternative to dolly based traditional cloning (TC). In this study, based on handmade cloning with minor modifications, an optimized bi-oocyte fusion (BOF) cloning method was established to produce GGTA1 KO porcine embryos using the CRISPR/Cas9 gene editing system. The GGTA1 gene is responsible for the generation of Gal epitopes on the surface of porcine cells, triggering hyperacute immune rejection in preclinical porcine-to-human xenotransplantation. The purpose of the present study is to establish an efficient protocol for activation of porcine oocyte cytoplast-fibroblast fused constructs developed to GGTA1 KO blastocysts by the zona-free bi-oocyte fusion cloning method. High percentages of cleavage (90 ±â€¯2.6%) and blastocyst rates (39 ±â€¯4.0%) were achieved upon treatment with demecolcine-assisted oocyte enucleation followed by 6 V alternating current for proper alignment and single-step fusion technique using a single direct current pulse of 1.0 kV/cm for 9 µs duration, compared to the double-step fusion method with combined chemical activation using thimerosal and dithiothreitol. Overall blastocyst rate was higher for oocyte enucleation by demecolcine (0.4 µg/ml) and 45 min incubation (42 ±â€¯1.5%) compared to without demecolcine incubation followed by complete chemical thimerosal/dithiothreitol activation (33 ±â€¯1.1%). The blastocyst rate (39 ±â€¯1.0%) was found to be significantly higher 1 h post-electrofusion, compared to at 0 and 4 h (28 ±â€¯1.5 and 6 ±â€¯1.5%, respectively). Blastocyst development rates for GGTA1 knockout embryos (38 ±â€¯1.76%) were comparable to those obtained with wild-type embryos (41.1 ±â€¯0.67%). In conclusion, we achieved high overall efficiency in production of GGTA1 KO blastocysts by modified HMC protocol.


Assuntos
Animais Geneticamente Modificados , Galactosiltransferases/metabolismo , Técnicas de Transferência Nuclear/veterinária , Sus scrofa , Transplante Heterólogo/veterinária , Animais , Sistemas CRISPR-Cas/genética , Galactosiltransferases/deficiência , Técnicas de Inativação de Genes , Oócitos/fisiologia
9.
PLoS One ; 14(12): e0226107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31821359

RESUMO

The CRISPR/Cas9 gene editing system has enhanced the development of genetically engineered animals for use in xenotransplantation. Potential limitations to the CRISPR/Cas9 system impacting the development of genetically engineered cells and animals include the creation of off-target mutations. We sought to develop a method to reduce the likelihood of off-target mutation while maintaining a high efficiency rate of desired genetic mutations for the GGTA1 gene. Extension of sgRNA length, responsible for recognition of the target DNA sequence for Cas9 cleavage, resulted in improved specificity for the GGTA1 gene and less off-target DNA cleavage. Three PAM sites were selected within exon 1 of the porcine GGTA1 gene and ten sgRNA of variable lengths were designed across these three sites. The sgRNA was tested against synthetic double stranded DNA templates replicating both the native GGTA1 DNA template and the two most likely off-target binding sites in the porcine genome. Cleavage ability for native and off-target DNA was determined by in vitro cleavage assays. Resulting cleavage products were analyzed to determine the cleavage efficiency of the Cas9/sgRNA complex. Extension of sgRNA length did not have a statistical impact on the specificity of the Cas9/sgRNA complex for PAM1 and PAM2 sites. At the PAM3 site, however, an observed increase in specificity for native versus off-target templates was seen with increased sgRNA length. In addition, distance between PAM site and the start codon had a significant impact on cleavage efficiency and target specificity, regardless of sgRNA length. Although the in vitro assays showed off-target cleavage, Sanger sequencing revealed that no off-target mutations were found in GGTA1 knockout cell lines or piglet. These results demonstrate an optimized method for improvement of the CRIPSR/Cas9 gene editing system by reducing the likelihood of damaging off-target mutations in GGTA1 knocked out cells destined for xenotransplant donor production.


Assuntos
Sistemas CRISPR-Cas/genética , DNA/metabolismo , Galactosiltransferases/genética , Edição de Genes/métodos , RNA Guia de Cinetoplastídeos/metabolismo , Animais , Sítios de Ligação , DNA/genética , Clivagem do DNA , Galactosiltransferases/deficiência , RNA Guia de Cinetoplastídeos/química , Ribonucleoproteínas/metabolismo , Suínos
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