Combinations of Growth Factors Regulating LIF/STAT3, WNT, and FGF2 Pathways Sustain Pluripotency-Related Proteins in Cat Embryonic Cells

Treatments of Porcine Nuclear Recipient Oocytes and Somatic Cell Nuclear Transfer-Generated Embryos with Various Reactive Oxygen Species Scavengers Lead to Improvements of Their Quality Parameters and Developmental Competences by Mitigating Oxidative Stress-Related Impacts

This study investigated the antioxidant effects of β-cryptoxanthin (BCX), hesperetin (HES), and icariin (ICA), and their effects on in vitro maturation of porcine oocytes and subsequent embryonic development of somatic cell nuclear transfer (SCNT). Treatment with 1 μM BCX (BCX-1) increased the developmental rate of porcine oocytes more than treatment with 100 μM HES (HES-100) or 5 μM ICA (ICA-5). The glutathione level and mRNA expression of antioxidant genes (NFE2L2, SOD1, and SOD2) were more increased in the BCX-1 group than in the HES-100 and ICA-5 groups, while the reactive oxygen species level was more decreased. Moreover, BCX improved the developmental capacity and quality of SCNT embryos. The total cell number, apoptotic cell rate, and development-related gene expression were modulated in the BCX-1 group to enhance embryonic development of SCNT. These results show that the antioxidant effects of BCX enhance in vitro maturation of porcine oocytes and subsequent embryonic development of SCNT.

The effect of a fibroblast growth factor, insulin-like growth factor, growth hormone, and Biolaminin 521 LN on the proliferative activity of cat stem cells

The wide use of cell technologies in clinical practice requires a large amount of cell material, which has led to improvement in culture conditions, making it possible to obtain more cell material in a shorter period of time. Thus, the purpose of our paper was to study the effects of different concentrations of an insulin-like growth factor (IGF-1), a fibroblast growth factor (FGF-2),| a growth hormone (rhGH), and Biolaminin 521 LN (LN 521) on the proliferative activity and genetic stability of stem cell cultures derived from the cat bone marrow, adipose tissue, and myocardium. Cell cultures for the experiment were obtained from the adipose tissue, bone marrow, and myocardium of a cat. Differences were found in the effects of the various growth promoters on the proliferative activity of cells in the culture. The IGF-1 demonstrated a positive effect on the proliferative activity of all cultures. The addition of the rhGH to the bone marrow-derived cell culture increased the size of the cells and decreased the proliferation index relative to the control group. The addition of the growth factors to the culture medium did not significantly increase the number of cells with altered karyotype in any of the cultures relative to the control group.

Small molecule inhibitors and culture conditions enhance therapeutic cell and EV potency via activation of beta-catenin and suppression of THY1

Primary cell therapy continues to face significant hurdles to therapeutic translation including the inherent variations that exist from donor to donor, batch to batch, and scale-up driven modifications to the manufacturing process. Cardiosphere-derived cells (CDCs) are stromal/progenitor cells with clinically demonstrated tissue reparative capabilities. Mechanistic investigations have identified canonical Wnt/β-catenin signaling as a therapeutic potency marker, and THY1 (CD90) expression as inversely correlated with potency. Here we demonstrate that the cardiosphere formation process increases β-catenin levels and enriches for therapeutic miR content in the extracellular vesicles of these cells, namely miR-146a and miR-22. We further find that loss of potency is correlated with impaired cardiosphere formation. Finally, our data show that small GSK3β inhibitors including CHIR, and BIO and "pro-canonical Wnt" culturing conditions can rescue β-catenin signaling and reduce CD90 expression. These findings identify strategies that could be used to maintain CDC potency and therapeutic consistency.

Reproductive biology and biotechnologies in wild felids

Conservation strategies in natural habitats as well as in breeding centers are necessary for maintaining and reinforcing viable populations of wild felids. Among the fundamental knowledge that is required for conservation breeding, a solid understanding of reproductive biology is critical for improving natural breeding and enhance genetic diversity. Additionally, it offers the opportunity to develop assisted reproductive technologies (ARTs) in threatened and endangered species. Conservation breeding and reproductive biotechnologies of wild felids have advanced in the past decade. It has been clearly shown that female felids have species and individual patterns of reproductive cycles and respond differently to exogenous hormones. In males, several species still have poor semen quality often due to the loss of genetic diversity in small populations. To overcome the challenges of natural breeding (incompatibility between individuals or suboptimal environment) and mitigate inbreeding, artificial insemination, embryo production and embryo transfer have been further developed in 24 wild cat species. Major factors limiting ART success are inconsistent responses to ovarian stimulation, variable quality of gametes and embryos, and preparation of recipient females. Additional approaches including stem cell technologies have been explored for future medical applications. However, there still is a critical need for better knowledge of feline reproductive biology and improvement of ARTs efficiency to increase the genetic diversity and create sustainable populations of wild felids.

Endogenous pluripotent factor expression after reprogramming cat fetal fibroblasts using inducible transcription factors

Incomplete transgene-silencing remains a challenge in the generation of induced pluripotent stem cells (iPSC) in felids-a critical family in biomedical and biodiversity conservation science. In this study doxycycline-inducible transgenes (NANOG, POU5F1, SOX2, KLF4, and cMYC) were used to reprogram cat fetal fibroblasts with the objective of obtaining iPSC with fully silenced transgenes. Colony formation was slower (14 vs. 8 days) and at lower efficiency than mouse embryonic fibroblasts (0.002% vs. 0.02% of seeded cells). Alkaline-phosphatase positive colonies were grown on feeder cells plus LIF and GSK3, MEK, and ROCK inhibitors. Cells could be passaged singly and transgene expression was silenced at passage 3 (P3) after doxycycline removal at P2. NANOG, POU5F1, and SOX2 were expressed at P3, P6, and P10, although at lower immunostaining intensities than in cat inner cell masses (ICM). Transcripts related to pluripotency (NANOG, POU5F1, SOX2, KLF4, cMYC, and REX1) and differentiation (FGF5, TBXT, GATA6, SOX17, FOXF1, PAX6, and SOX1) were assessed by a reverse transcription-quantitative polymerase chain reaction in iPSC and embryoid bodies. The immunostaining patterns, relatively low levels of NANOG and REX1 in comparison to ICM along with the expression of TBXT (mesoderm) suggested that cells were a mix of reprogrammed pluripotent and differentiating cells.