Combination of cell signaling molecules can facilitate MYOD1-mediated myogenic transdifferentiation of pig fibroblasts

Background Myogenic transdifferentiation can be accomplished through ectopic MYOD1 expression, which is facilitated by various signaling pathways associated with myogenesis. In this study, we attempted to transdifferentiate pig embryonic fibroblasts (PEFs) myogenically into skeletal muscle through overexpression of the pig MYOD1 gene and modulation of the FGF, TGF-β, WNT, and cAMP signaling pathways. Results The MYOD1 overexpression vector was constructed based on comparative sequence analysis, demonstrating that pig MYOD1 has evolutionarily conserved domains across various species. Although forced MYOD1 expression through these vectors triggered the expression of endogenous muscle markers, transdifferentiated muscle cells from fibroblasts were not observed. Therefore, various signaling molecules, including FGF2, SB431542, CHIR99021, and forskolin, along with MYOD1 overexpression were applied to enhance the myogenic reprogramming. The modified conditions led to the derivation of myotubes and activation of muscle markers in PEFs, as determined by qPCR and immunostaining. Notably, a sarcomere-like structure was observed, indicating that terminally differentiated skeletal muscle could be obtained from transdifferentiated cells. Conclusions In summary, we established a protocol for reprogramming MYOD1-overexpressing PEFs into the mature skeletal muscle using signaling molecules. Our myogenic reprogramming can be used as a cell source for muscle disease models in regenerative medicine and the production of cultured meat in cellular agriculture.This work was supported by the BK21 Four program, the Korea Evaluation Institute of Industrial Technology (KEIT; 20012411), and the National Research Foundation of Korea (NRF) grant (2021R1A2C4001837)

The number of primitive endoderm cells in the inner cell mass is regulated by platelet-derived growth factor signaling in porcine preimplantation embryos

Objective Discovering the mechanism of cell specification is important to manipulate cellular lineages. To obtain lineage-specific cell lines, the target lineage needs to be promoted, and counterpart lineages should be suppressed. Embryos in the early blastocyst stage possess two different cell populations, the inner cell mass (ICM) and trophectoderm. Then, cells in the ICM segregate into epiblasts (Epi) and primitive endoderm (PrE). PrE cells in embryos show specific expression of platelet-derived growth factor (PDGF) and its receptor, PDGF receptor A (PDGFRA). In this study, we suppressed PDGF signaling using two methods (CRISPR/Cas9 injection and inhibitor treatment) to provide insight into the segregation of embryonic lineages. Methods CRISPR/Cas9 RNAs were injected into parthenogenetically activated and in vitro fertilized embryos. The PDGF receptor inhibitor AG1296 was treated at 0, 5, 10, and 20 μM concentration. The developmental competence of the embryos and the number of cells expressing marker proteins (SOX2 for ICM and SOX17 for PrE) were measured after the treatments. The expression levels of the marker genes with the inhibitor were examined during embryo development. Results Microinjection targeting the PDGF receptor (PDGFR) A reduced the number of SOX17-positive cell populations in a subset of day 7 blastocysts (n = 9/12). However, microinjection accompanied diminution of Epi cells in the blastocyst. The PDGF receptor inhibitor AG1296 (5 μM) suppressed SOX17-positive cells without reducing SOX2-positive cells in both parthenogenetic activated and in vitro fertilized embryos. Within the transcriptional target of PDGF signaling, the inhibitor significantly upregulated the Txnip gene in embryos. Conclusion We identified that PDGF signaling is important to sustain the PrE population in porcine blastocysts. Additionally, treatment with inhibitors was a better method to suppress PrE cells than CRISPR/Cas9 microinjection of anti-PDGF receptor α gene, because microinjection suppressed number of Epi cells. The PDGF receptor might control the number of PrE cells by repressing the proapoptotic gene Txnip. Our results can help to isolate Epi-specific cell lines from blastocysts

Baseline characteristics of the Korean genetic cohort of inherited cystic kidney disease

Background Identifying genetic mutations in individuals with inherited cystic kidney disease is necessary for precise treatment. We aimed to elucidate the genetic characteristics of cystic kidney disease in the Korean population. Methods We conducted a 3-year prospective, multicenter cohort study at eight hospitals from May 2019 to May 2022. Patients with more than three renal cysts were enrolled and classified into two categories, typical autosomal dominant polycystic kidney disease (ADPKD) and atypical PKD. We identified the clinical characteristics and performed a genetic analysis using a targeted gene panel. Results A total of 725 adult patients were included in the study, of which 560 (77.2%) were diagnosed with typical ADPKD and 165 (22.8%) had atypical PKD. Among the typical ADPKD cases, the Mayo imaging classification was as follows: 1A (55, 9.9%), 1B (149, 26.6%), 1C (198, 35.8%), 1D (90, 16.3%), and 1E (61, 11.0%). The atypical PKD cases were classified as bilateral cystic with bilateral atrophic (31, 37.3%), lopsided (27, 32.5%), unilateral (nine, 10.8%), segmental (eight, 9.6%), bilateral cystic with unilateral atrophic (seven, 8.4%), and asymmetric (one, 1.2%). Pathogenic variants were found in 64.3% of the patients using the ciliopathy-related targeted gene panel. The typical ADPKD group demonstrated a higher discovery rate (62.3%) than the atypical PKD group (41.8%). Conclusion We present a nationwide genetic cohort’s baseline clinical and genetic characteristics for Korean cystic kidney disease

Coherent spin waves driven by optical spin-orbit torque

Phase-coherent spin waves can be generated by magnetic field pulse, spin current pulse, or optical pulse. Here we use optical spin-orbit torque, originating from the conversion of an optical pulse into a spin-polarized current pulse, to excite spin waves in the frequency range from GHz to THz. We investigate the frequency, amplitude, and damping of the spin waves of Co thin films. From the frequency analysis, we determine the stiffness of Co spin waves to be 5 meV nm(2). From the amplitude analysis, we show that the Co layer acts as a cavity for spin waves. From the damping analysis, we observe that the damping enhancement due to the spin pumping effect is about two times larger in spin waves than in uniform precession.11Nsciescopu

Magnetization dynamics of antiferromagnetic metals of PtMn and IrMn driven by a pulsed spin-transfer torque

© 2021 Author(s). Published under an exclusive license by AIP Publishing. Antiferromagnets are promising materials for memory devices owing to their ultrafast spin dynamics. For efficient control of antiferromagnets, a direct interaction between the spin current and local magnetization of the sublattice is required. In this study, we demonstrated that a short-pulsed spin current can induce fast dynamics of metallic antiferromagnets of PtMn and IrMn via spin-transfer torque on the magnetization of sublattices. We employed two methods to generate a short-pulsed spin current, namely ultrafast demagnetization of a ferromagnet and optical spin polarization of a heavy metal. The magnetization dynamics were measured using the time-resolved magneto-optical Kerr effect and were analyzed using the Landau-Lifshitz-Gilbert equation. Our results provide important evidence of the direct interaction between the magnetization of antiferromagnets and spin current.11Nsciescopu

MISFITSTRAIN AND GROWTH CHARACTERISTICS OF INAS/GAAS QUANTUM DOTS GROWN BY MOLECULAR BEAM EPITAXY

11scopu

The immunosuppressive effect of embryonic stem cells and mesenchymal stem cells on both primary and secondary alloimmune responses

Recently, both embryonic stem cells and mesenchymal stem cells have been demonstrated to have immunosuppressive effects. The purpose of this study was to elucidate whether the embryonic stem cells and/or mesenchymal stem cells modulate both primary and secondary alloimmune responses. Both stem cells suppressed in vitro proliferation and cytokine production in primary alloimmune responses. They also suppressed in vitro proliferation and cytokine production of the allosensitized CD44(+) memory T cells. However, they failed to prolong skin graft survival across both a major mismatch barrier (BALB/C, C57BL6/J) and a minor mismatch barrier (male to female). In conclusion, both embryonic stem cells and mesenchymal stem cells can suppress secondary alloimmune response in vitro as well as primary alloimmune responses; however, neither embryonic stem cells nor mesenchymal stem cells suppressed allograft rejection in stringent murine skin transplantation models. (C) 2010 Elsevier B.V. All rights reserved.Ding YC, 2009, DIABETES, V58, P1797, DOI 10.2337/db09-0317Ge W, 2009, AM J TRANSPLANT, V9, P1760, DOI 10.1111/j.1600-6143.2009.02721.xPopp FC, 2009, TRANSPLANTATION, V87, pS57, DOI 10.1097/TP.0b013e3181a288aaMarcen R, 2009, DRUGS, V69, P2227, DOI 10.2165/11319260-000000000-00000Casiraghi F, 2008, J IMMUNOL, V181, P3933Valujskikh A, 2008, CURR OPIN ORGAN TRAN, V13, P344Dressel R, 2008, PLOS ONE, V3, DOI 10.1371/journal.pone.0002622Kishi Y, 2008, CELL TRANSPLANT, V17, P1095Koch CA, 2008, STEM CELLS, V26, P89, DOI 10.1634/stemcells.2007-0151Yang J, 2007, P NATL ACAD SCI USA, V104, P19954, DOI 10.1073/pnas.0704397104Bharat A, 2007, TRANSPLANTATION, V84, P1316, DOI 10.1097/01.tp.0000288192.11396.70Caspi O, 2007, J AM COLL CARDIOL, V50, P1884, DOI 10.1016/j.jacc.2007.07.054Magliocca JF, 2006, STEM CELLS DEV, V15, P707Herszfeld D, 2006, NAT BIOTECHNOL, V24, P351, DOI 10.1038/nbt1197Aggarwal S, 2005, BLOOD, V105, P1815, DOI 10.1182/blood-2004-04-1559Burt RK, 2004, J EXP MED, V199, P895, DOI 10.1084/jem.20031916Li L, 2004, STEM CELLS, V22, P448Krampera M, 2003, BLOOD, V101, P3722Fandrich F, 2002, NAT MED, V8, P171Bartholomew A, 2002, EXP HEMATOL, V30, P42

Linoleic acid reduces apoptosis via NF-kB during the in vitro development of induced parthenogenic porcine embryos

Fatty acid has a various role in preimplantation embryo development. Especially, Linoleic acid, polyunsaturated fatty acid, has been reported to affect the apoptosis pathway via nuclear transcription factorkappa B. But to date, the function of NF-kB has not been demonstrated in porcine preimplantation embryos. We demonstrated that linoleic acid had a positive effect on embryo development at a certain concentration(25 mM), but developmental failure was observed at higher concentration. Furthermore, the expression level of NF-kB increased, unlike that of IL-6, as the concentration of linoleic acid increased. Interestingly, the concentration of NF-kB was found to increase even at the concentration of linoleic acid at which embryo development decreased. We found that pro-apoptotic gene expression was downregulated in the linoleic acid-treated group. It was also found that M OE-1, an anti-apoptotic gene known to be unaffected by IL-6, was found to be increased at the mRNA level in the linoleic acid-treated group. As the concentration of NF-kB increased, the nuclear translocation of C-JUN gradually increased dependent on the linoleic acid concentration. It was confirmed that NF-kB is an important factor in porcine embryos by treated ammonium pyrrolidinedithiocarbamate (APDC 0.1 mM, an inhibitor of NF-kB) affected NF-kB protein expression, IL-6 expression, and blastocyst production. These data supported porcine embryos can use exogenous linoleic acid as a metabolic energy source via NF-kB. (c) 2022 Elsevier Inc. All rights reserved.N