Rate Of Differentiation Research Articles

Chicken Embryo Fibroblast Viability and Trans-Differentiation Potential for Cultured Meat Production Across Passages.

This study was conducted to analyze the viability of primary chicken embryo fibroblasts and the efficiency of adipogenic trans-differentiation for cultured meat production. In isolating chicken embryo fibroblasts (CEFs) from a heterogeneous cell pool containing chicken satellite cells (CSCs), over 90% of CEFs expressed CD29 and vimentin. The analysis of the proliferative capabilities of CEFs revealed no significant differences in EdU-positive cells (%), cumulative cell number, doubling time, and growth rate from passage 1 to passage 9 (p > 0.05). This indicates that CEFs can be isolated by 2 h of pre-plating and survive stably up to passage 9, and that primary fibroblasts can serve as a valuable cell source for the cultured meat industry. Adipogenic trans-differentiation was induced up to passage 9 of CEFs. As passages increased, lipid accumulation and adipocyte size significantly decreased (p < 0.05). The reduced differentiation rate of primary CEFs with increasing passages poses a major challenge to the cost and efficiency of cultured meat production. Thus, effective cell management and the maintenance of cellular characteristics for a long time are crucial for ensuring stable and efficient cultured fat production in the cultured meat industry.

Spleen Morphogenesis during the Neonatal Period in Rats Exposed to Endocrine Disruptor DDT

Spleen morphogenesis during the neonatal period in rats exposed in prenatal and postnatal development to low doses of dichlorodiphenyltrichloroethane (DDT), a persistent universal pollutant with endocrine disrupting properties, was studied. More intensive formation of periarterial lymphoid sheaths and marginal zone and simultaneously decreased rate of B-cell differentiation in the spleen were revealed. A higher content of differentiating T-cells and a lower number of cytotoxic T-lymphocytes by the end of the first week of life indicates a decrease in the differentiation of the latter. A lower content of neutrophils in the marginal zone also indicates a delay in the rate of functional development of lymphoid tissue, as opposed to morphological, in rats developing under exposure to low doses of DDT.

Incorporation of Superparamagnetic Magnetic–Fluorescent Iron Oxide Nanoparticles Increases Proliferation of Human Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) have significant therapeutic potential and their use requires in-depth studies to better understand their effects. Labeling cells with superparamagnetic iron oxide nanoparticles allows real-time monitoring of their location, migration, and fate post-transplantation. This study aimed to investigate the efficacy and cytotoxicity of magnetic–fluorescent nanoparticles in human adipose tissue-derived mesenchymal stem cells (hADSCs). The efficacy of Molday ION rhodamine B (MIRB) labeling in hADSCs was evaluated and their biocompatibility was assessed using various techniques and differentiation assays. Prussian blue and fluorescence staining confirmed that 100% of the cells were labeled with MIRB and this labeling persisted for at least 3 days. Transmission electron microscopy revealed the internalization and clustering of the nanoparticles on the outer surface of the cell membrane. The viability assay showed increased cell viability 3 days after nanoparticle exposure. Cell counts were higher in the MIRB-treated group compared to the control group at 3 and 5 days and an increased cell proliferation rate was observed at 3 days post-exposure. Adipogenic, osteogenic, and chondrogenic differentiation was successfully achieved in all groups, with MIRB-treated cells showing an enhanced differentiation rate into adipocytes and osteocytes. MIRB was efficiently internalized by hADSCs but induced changes in cellular behavior due to the increased cell proliferation rate.

Multifunctional conductive stem cell delivery hydrogel combined with low-frequency pulsed electromagnetic fields for spinal cord injury repair

Spinal cord injury (SCI) is a severe traumatic disease for which no satisfying treatment is available. The severe inflammatory reactions and poor endogenous regenerative capacity cause difficulty in functional recovery. Neural stem cells (NSCs) transplantation is currently a promising treatment for repairing SCI. However, there is a lack of effective ways to improve the survival rates of NSCs and promote the neuron differentiation rates of NSCs. Conductive hydrogel can mimic environment which is suitable for neurodevelopment. Low-frequency pulsed electromagnetic fields (LPEMFs) have the advantages of safety, non invasiveness, and tissue repair, making it a potential method of repairing SCI. In this study, an injectable, self-healing magnetic, and conductive hydrogel was synthesized to carry out NSCs with LPEMFs for repairing SCI. In vitro experiments, under the treatment of LPEMFs and conductive hydrogel, the microglia tend to polarize into M2 phenotype, rather than M1 phenotype. Meanwhile, NSCs tend to differentiate into neuronal direction. In SCI model, conductive hydrogel loaded with NSCs combined with LPEMFs can promote functional recovery, through reducing inflammation and promoting neuron differentiation of NSCs. This study provides a novel NSCs transplantation strategy combined with physical interventions for SCI treatment, which brings a new desire to repair SCI.

Grifola frondosa extract as a fetal bovine serum supplement for the culture of bovine muscle satellite cells under low serum conditions

Expensive fetal bovine serum (FBS) is a major obstacle to the production of cultivated meat. However, because FBS substitutes do not sufficiently induce cell proliferation, a good alternative is to reduce the amount of FBS and use ingestible additives to promote cell proliferation. In this study, Grifola frondosa extract (GFE) was used to investigate its potential as an additive to promote myogenesis of bovine muscle satellite cells from Hanwoo cattle under low serum conditions (10 % FBS). GFE treated with 10 % FBS only during the proliferation period not only increased cell proliferation and related biomarkers in a concentration-dependent manner (0.78–12.5 μg/mL), but also increased cell differentiation. Additionally, differentiation was promoted when cells were with GFE treated only during the differentiation period. Especially GFE at 12.5 µg/mL induced significantly higher proliferation and differentiation rates than 20 % FBS medium. In particular, compared to treatment alone in the proliferation or differentiation periods, GFE treatment in both periods contributed to an increase in the differentiation rate and significantly enhanced total protein production. The integration of GFE into cultivated meat production presents a promising approach to reducing FBS dependence, lowering costs, and enhancing scalability, aligning with sustainability and consumer acceptance goals.

Induction of human stem cells into ameloblasts by reaggregation strategy

BackgroundHuman epithelium-derived stem cells and induced pluripotent stem cells (hiPSCs) possess the capability to support tooth formation and differentiate into functional enamel-secreting ameloblasts, making them promising epithelial-component substitutes for future human tooth regeneration. However, current tissue recombination approaches are not only technically challenging, requiring precise induction procedures and sophisticated microsurgery, but also exhibit low success rates in achieving tooth formation and ameloblastic differentiation.MethodsSuspended human keratinocyte stem cells (hKSCs) or cells from three hiPSC lines were directly mixed with dissociated embryonic mouse dental mesenchymal cells (mDMCs) that possess odontogenic potential in different proportions and reaggregated them to construct bioengineered tooth germs. The success rates of tooth formation and ameloblastic differentiation were confirmed after subrenal culture. The sorting capability, sequential development, and ameloblastic differentiation of stem cells were examined via GFP tracing, RT-PCR, and histological analysis, respectively.ResultsOur reaggregation approach achieved an impressive success rate of more than 90% in tooth formation and 100% in ameloblastic differentiation when the chimeric tooth germs contained 1%~10% hKSCs or 5% hiPSCs. In addition, we observed that hiPSCs, upon exposure to mDMCs, initially transformed into epidermal cells, as indicated by KRT14 and CD29 expression, before progressing into dental epithelial cells, as indicated by SP6 and SHH expression. We also found that epithelial-derived hiPSCs, when reaggregated with mDMCs, were more favorable for tooth formation than their mesenchymal-derived counterparts.ConclusionsThis study establishes a simplified yet highly effective cell-cell reaggregation strategy for inducing stem cells to support tooth formation and differentiate into functional ameloblasts, paving the way for novel approaches for the development of stem cell-based tooth organoids and bioengineered tooth germs in vitro.

Heavy metal in radiation therapy: A simple method to differentiate hip prosthesis materials.

In recent years, the number of hip replacement patients receiving radiation therapy has steadily increased. In parallel, strategies have been developed to reduce metal artifacts in computed tomography (CT) images and improve the accuracy of dose calculation algorithms. However, in certain situations, knowledge of the type of prosthesis material is required to accurately determine the dose distribution. This study aims to identify physical materials in hip prostheses to correctly assign them in the treatment planning system and improve dose calculation accuracy. We first verified the validity of the extended CT mass density calibration curve measured on titanium (Ti) and stainless steel (SS) metal inserts of two different diameters. Then using dedicated reference objects of various circular diameters, we developed a method based on interpolation functions to differentiate between Ti and SS material groups. Forty data sets from 18 patients were used to validate our method on two different reconstruction kernels: a standard Br44f and the electron DirectDensity (Sd40f) kernels from Siemens. Hounsfield units (HU) of Ti and SS inserts were found to vary widely depending on insert diameter, CT spectrum, and reconstruction kernels due to cupping artifacts. The largest HU difference (-79%) was obtained for SS at 70kV with Br44f when the diameter increased from 8 to 30mm. Therefore, under these conditions, the extended CT-density calibration curve is not recommended for heavy metal density determination. Using our interpolation-based method, we achieved excellent detection (100%) and material differentiation (100%) results for stems in both reconstruction kernels. At CT energies between 110 and 140kV, the detection and material differentiation rates were 93.3% and 92.9% for the heads and 93.3% and 92.9% for the acetabular cups, respectively, with the Br44f. Similarly, the use of Sd40f resulted in detection and differentiation rates of 94.7% and 100% for the heads and 100% and 95.0% for the acetabular cups, respectively. This method makes it possible to differentiate between hip prosthesis materials and correctly assign them to the Ti or SS group without prior knowledge of the prosthesis type, regardless of the reconstruction kernels. In combination with the Acuros XB (Varian) or Monte Carlo dose algorithms, excellent dosimetric accuracy can be achieved even in the vicinity of hip prostheses. By performing basic measurements, the method can be adapted to other CT units and reconstruction kernels, replacing the use of an extended CT-density calibration curve.

Innovative Strategies for Liver Transplantation: The Role of Mesenchymal Stem Cells and Their Cell-Free Derivatives.

Despite being the standard treatment for end-stage liver disease, liver transplantation has limitations like donor scarcity, high surgical costs, and immune rejection risks. Mesenchymal stem cells (MSCs) and their derivatives offer potential for liver regeneration and transplantation. MSCs, known for their multipotency, low immunogenicity, and ease of obtainability, can differentiate into hepatocyte-like cells and secrete bioactive factors that promote liver repair and reduce immune rejection. However, the clinical application of MSCs is limited by risks such as aberrant differentiation and low engraftment rates. As a safer alternative, MSC-derived secretomes and extracellular vesicles (EVs) offer promising therapeutic benefits, including enhanced graft survival, immunomodulation, and reduced ischemia-reperfusion injury. Current research highlights the efficacy of MSC-derived therapies in improving liver transplant outcomes, but further studies are necessary to standardize clinical applications. This review highlights the potential of MSCs and EVs to address key challenges in liver transplantation, paving the way for innovative therapeutic strategies.

Variation in spatial population structure in the Anopheles gambiae species complex.

Anopheles gambiae, Anopheles coluzzii, and Anopheles arabiensis are three of the most widespread vectors of malaria parasites, with geographical ranges stretching across wide swaths of Africa. Understanding the population structure of these closely related species, including the extent to which populations are connected by gene flow, is essential for understanding how vector control implemented in one location might indirectly affect vector populations in other locations. Here, we assessed the population structure of each species based on a combined data set of publicly available and newly processed whole-genome sequences. The data set included single nucleotide polymorphisms from whole genomes of 2,410 individual mosquitoes sampled from 128 locations across 19 African countries. We found that A. gambiae sampled from several countries in West and Central Africa showed low genetic differentiation from each other according to principal components analysis (PCA) and ADMIXTURE modeling. Using Estimated Effective Migration Surfaces (EEMS), we showed that this low genetic differentiation indicates high effective migration rates for A. gambiae across this region. Outside of this region, we found eight groups of sampling locations from Central, East, and Southern Africa for which A. gambiae showed higher genetic differentiation, and lower effective migration rates, between each other and the West/Central Africa group. These results indicate that the barriers to and corridors for migration between populations of A. gambiae differ across the geographical range of this malaria vector species. Using the same methods, we found higher genetic differentiation and lower migration rates between populations of A. coluzzii in West and Central Africa than for A. gambiae in the same region. In contrast, we found lower genetic differentiation and higher migration rates between populations of A. arabiensis in Tanzania, compared to A. gambiae in the same region. These differences between A. gambiae, A. coluzzii, and A. arabiensis indicate that migration barriers and corridors may vary, even between very closely related species. Overall, our results demonstrate that migration rates vary both within and between species of Anopheles mosquitoes, presumably based on species-specific responses to the ecological or environmental conditions that may impede or facilitate migration, and the geographical patterns of these conditions across the landscape. Together with previous findings, this study provides robust evidence that migration rates between populations of malaria vectors depend on the ecological context, which should be considered when planning surveillance of vector populations, monitoring for insecticide resistance, and evaluating interventions.

Cleavage and polyadenylation factors are potential regulators of adipogenesis

ObjectiveAlternative polyadenylation (APA) is a co-transcriptional process that leads to isoform diversity in the 3’ ends of mRNAs. APA is known to occur during differentiation, and its dysregulation is observed in diseases like cancer and autoimmune disorders. It has been previously reported that differentiation of 3T3-L1 cells to adipocytes leads to an overall lengthening of mRNAs, but the proteins involved in this regulation have not been identified. The expression levels of subunits of the cleavage and polyadenylation (C/P) complex can regulate the choice of poly(A) site, which in turn can affect different cellular activities. In this paper, we studied the change in levels of C/P proteins during 3T3-L1 differentiation.ResultsWe observed that while the RNA expression of these proteins is unchanged during differentiation, the protein levels of some subunits do change, including a decrease in levels of CPSF73, the nuclease that cuts at the poly(A) site. However, overexpression of CPSF73 alone does not affect the efficiency and rate of differentiation.

Insights into the bZIP gene family in Osmanthus fragrans and the role of OfbZIP98 in the callus and flower

Osmanthus fragrans has important ornamental and economic value. As the callus re-differentiation process is difficult, a genetic transformation system has not been successfully established in O. fragrans. The basic leucine zipper (bZIP) transcription factors play an important role in plant growth and development. A total of 116 OfbZIP genes were identified in O. fragrans using bioinformatics methods. According to the evolutionary relationships, these genes were divided into 12 subfamilies and were found to be unevenly distributed on 23 chromosomes of O. fragrans. The quantitative real-time PCR results showed that the expression trend of OfbZIP98 was consistent with the proliferation of O. fragrans callus. The subcellular localization and yeast self-activation results showed that OfbZIP98 was localized in the nucleus and had self-activation activity. Further, phenotypic observation of over-expressed tobacco showed that compared with the wild type (WT), the transgenic strain formed callus 4 d earlier, and callus re-differentiation began on day 15. Analysis of the callus differentiation rate showed that after 20 d of culture, the differentiation rate of the leaf callus of the transgenic strain was about twice that of the WT plants. In addition, measurements of corolla diameter, corolla circumference, corolla area, and corolla tube diameter indicated that the petals of the transgenic strain were significantly larger than the WT plants. Our results showed that OfbZIP98 has the important function of promoting callus growth, re-differentiation, and flower organ enlargement. These findings provide new insights into the potential role of OfbZIP98 in the growth and development of O. fragrans.

Establishment of Shoot-tip Regeneration System of Watermelon

The aim of this study was to establish a regeneration system of watermelon. Watermelon W1 was selected as the experimental material using seedling shoots as a receptor. The effects of different concentrations of 6-Benzylaminopurine (6-BA) on the shoot-tip of watermelon seedlings were studied. Number of shoots at the stem tip were counted every other day until the new buds reached 2 cm. The new stem tip was cut, and the effect of different concentrations of Murashige and Skoog (MS) medium on the number of regenerated roots and root length of shoots were studied. The results showed that the differentiation rate was highest when the 6-BA concentration was 0.7 mg/mL to 0.8 mg/mL. The optimum concentration for root regeneration was 1/8 MS. At this concentration, the number rooted was the highest, and root length was also promoted.

Population genetics and evolutionary history of the intertidal brittle star Ophiothrix (Ophiothrix) exigua in the northern China Sea.

Ophiothrix (Ophiothrix) exigua is a common brittle star in the northwestern Pacific. As a dominant species, O. exigua inhabiting the intertidal rocky ecosystem are affected by multiple environmental stressors, but molecular insights into their genetic population structure remain poorly studied. In this study, we investigated the population genetics and evolutionary history of six O. exigua populations from the northern China Sea using mitochondrial (COI, NAD4) and nuclear (ITS2, 18S) gene markers. High haplotype diversity, low nucleotide diversity, and low rates of gene differentiation among the populations of O. exigua were detected. Pairwise genetic differentiation (ΦST) statistics between different localities were negative or low and insignificant, suggesting strong gene flow of this species over the study areas. The phylogenetic analyses showed that the populations exhibited high homogeneity between localities in our study area. Demographic analyses indicated that the populations experienced sustained expansion around 0.2 million years ago. This expansion was likely related to transgressions events in the Yellow Sea during the Pleistocene period. Additional samples of O. exigua from disparate geographical locations, especially the Japan Sea and the Korean Peninsula, will be needed to unravel the population genetic patterns and evolutionary history of this species.

Sesquiterpenoids from the roots and rhizomes of Valeriana officinalis var. latifolia

The genus Valeriana is used in traditional Chinese medicine to treat nervous disorders, sleep disorders, epilepsy and skin diseases. A large number of sesquiterpenoids from this genus have been found to exhibit anti-inflammatory, antiproliferative, anti-influenza virus and neuroprotective activities. In order to discover more sesquiterpenoids with structural diversity and bioactivity from Valeriana plants, fifteen sesquiterpenoids, including ten undescribed ones, valernaenes A−J (1, 5−7, 9−11 and 13−15), were isolated from the roots and rhizomes of Valeriana officinalis var. latifolia. Their structures were elucidated by extensive spectroscopic techniques (1D, 2D NMR and HRESIMS) and electronic circular dichroism (ECD) calculation. Structurally, valernaenes C (6) and D (7) were two caryophyllane-type norsesquiterpenoids. In addition, valernaenes A (1) and F (10) exhibited anti-influenza virus activity with EC50 values of 38.76 ± 1.44 and 23.01 ± 4.89 μM, respectively. Furthermore, caryophyllenol A (2) showed promoting effect on nerve growth factor (NGF)-mediated neurite outgrowth in PC12 cells with differentiation rate of 12.26% at a concentration of 10 μM. This study not only enriched the structural diversity of sesquiterpenoids in the genus Valeriana, but also provided theoretical basis for the discovery of anti-influenza virus and neuroprotective agents from this genus.

Construction of Optimal Regeneration System for Chrysanthemum '11-C-2' Stem Segment with Buds.

Chrysanthemum morifolium '11-C-2' is a variety of chrysanthemums with high ornamental and tea value, experiencing significant market demand. However, as cultivation areas expand, issues such as viral infection, germplasm degradation, low proliferation coefficient, and slow proliferation rate arise, necessitating the establishment of an efficient in vitro regeneration system. This study, based on the principles of orthogonal experimental design, explored the regeneration system of Chrysanthemum cultivar '11-C-2' using sterile seedlings. The research focused on three key stages: adventitious bud differentiation, rooting culture, and acclimatization-transplantation, employing shoot-bearing stem segments and leaves as explants. The findings indicate that the optimal explant for the Chrysanthemum '11-C-2' sterile seedlings is the shoot-bearing stem segment. The best medium for adventitious bud differentiation was determined to be MS supplemented with 1.5 mg/L 6-BA and 0.5 mg/L NAA. Bud differentiation began on day 17 with a 100% differentiation rate, completing around day 48. The maximum differentiation coefficient reached 87, with an average of 26.67. The adventitious buds were then cultured for rooting in the optimal medium of 1/2 MS supplemented with 0.1 mg/L NAA. Rooting was initiated on day 4 and was completed by day 14, achieving a rooting rate of 97.62%. After a 5-day acclimatization under natural light, the rooted seedlings were transplanted into a growth substrate with a peat-to-vermiculite ratio of 1:2. The plants exhibited optimal growth, with a transplantation survival rate of 100%. The findings provide data support for the efficient large-scale propagation of '11-C-2' and lay the foundation for germplasm preservation and genetic transformation research of tea chrysanthemums.

A Global Database of Pitted Cones on Mars for Research on Martian Volcanism

This study presents a global database of pitted cones on Mars. This database was created using an active deep-learning approach based on a global mosaic of Mars Context Camera (CTX) images, followed by extensive manual verification. The global database contains 250,547 pitted cones along with their central coordinates and diameters. 94.2% of the pitted cones have diameters ranging from 100 m to 1 km. Most of them are in the northern lowlands, while some are scattered in the southern highlands. Systematic evaluation of the extracted pitted cones is performed in Isidis Planitia, Acidalia Planitia, and Cerberus Palus on Mars. The results reveal that the precision ranges from 79.2% to 85.6%, and the recall rate ranges from 62.4% to 87.7%, indicating a varying among regions but satisfactory performance. Manual digitizing evaluation indicates that over 94.1% of manual labels by different annotators have a differentiation rate of 10%, showing promising precision and consistency. This global database can facilitate further research on the origin and evolution of pitted cones on Mars.

ECM components are essential for proper in vitro myogenesis

Objective: In vitro models of skeletal muscle often utilize primary myoblast cells or myoblast cell lines. Myoblasts require adhesion to the extracellular matrix (ECM) to grow, proliferate, migrate, and differentiate in their natural environments in vivo. To meet the adhesion needs of adhesive cells under in vitro conditions, culture surfaces are coated with various biological or synthetic compounds. Within the scope of the study, the differentiation potential of H2K myoblasts, a cell line resembling primary myoblasts, were comparatively evaluated through morphological analysis on culture surfaces coated with various ECM and synthetic materials. Methods: The culture surfaces were coated with fibronectin and laminin, the major adhesion proteins of ECM; gelatin, a molecular derivative of collagen; matrigel, an ECM extract; and PLL, a synthetic poly-amino acid. Cells were allowed to differentiate in each culture medium for 4 days and their capacity to adhere to the surface and differentiation rates from myoblast to myotube were evaluated by morphological analysis. Results: In the uncoated culture environment, cells could only attach to 30-50% of the culture surface and myotube development was limited and not aligned with each other. On surfaces coated with PLL, no myotube development was observed and cells could only attach to 30-40% of the culture surface. Myotube development and alignment were similar on all surfaces coated with ECM components. On surfaces coated with ECM components laminin, fibronectin and matrigel, cells covered the entire culture surface and exhibited similar myotube development. However, on surfaces coated with gelatin, both cell adhesion to the surface and myotube development were limited compared to other ECM components. The mean myotube diameters of fibronectin, laminin, matrigel, PLL+laminin and gelatin were 49.71µm (±16.3µm), 52.31µm (±15.7µm), 51.9µm (±15.3µm), 53.06µm (±14.2µm) and 35.25µm (±11.4µm), respectively. Conclusion: Within the scope of the study, it was revealed that coating the culture surface with only a cationic material such as PLL does not support myogenesis and ECM components are needed for cell viability and differentiation.

Nutrology and molecular state of art in muscle recovery and sports performance: a systematic review

Introduction: Nutrition makes it possible to recover from the negative impact of an injury induced by physical exercise. Recent progress has been made regarding gut microbiota, regenerative nutrition, and skeletal muscle metabolism. MicroRNAs (miRs) have emerged as critical regulators of numerous biological processes, modulating gene expression at the post-transcriptional level. Objective: It was to carry out a systematic review to elucidate the main considerations of nutrology and molecular state of art through exosomes, microRNAs, and nutrients in muscle recovery and sports performance. Methods: The systematic review rules of the PRISMA Platform were followed. The research was carried out from April to June 2023 in Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 237 articles were found. A total of 107 articles were evaluated in full and 52 were included and developed in this systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 47 studies with a high risk of bias and 70 studies that did not meet GRADE. Based on the findings, it was concluded that dietary manipulations and metabolites may affect tissue stem cell fate decisions. Self-renewal and differentiation of mesenchymal stem cells can be regulated by manipulating vitamin C, A, or D levels and valine restriction. miRs play an important role as regulatory molecules during the muscle healing process. Myoblasts are known to secrete exosomes enriched with miRs into the inflammatory environment, whereby miR-224 is transferred to macrophages to inhibit M2 polarization. Additional data demonstrate that WNT-9a may be a direct target of miR224 for macrophage polarization. The results showed that miR-122 and myogenic markers were down-regulated in C2C12 cells after TGF-β stimulation, and overexpression of miR-122 can restore myogenesis inhibited by TGF-β. Evidence suggests that the exosome derived from mesenchymal stem cells exhibits functions similar to mesenchymal stem cells with low immunogenicity and without tumorization. High rates of intestinal self-renewal are enabled by intestinal stem cells (LGR5+) at the base of intestinal crypts. LGR5+ activity, including proliferation and differentiation rates, is affected by large shifts in nutrient availability, as occurs on a high-fat diet or fasting. The practice of physical activity, endogenous metabolites, and dietary nutrients can directly influence epigenetic enzymes.

Modulation of cell differentiation and growth underlies the shift from bud protection to light capture in cauline leaves.

Plant organs have evolved into diverse shapes for specialized functions despite emerging as simple protrusions at the shoot apex. Cauline leaves serve as photosynthetic organs and protective structures for emerging floral buds. However, the growth patterns underlying this dual function remain unknown. Here, we investigate the developmental dynamics shaping Arabidopsis (Arabidopsis thaliana) cauline leaves underlying their functional diversification from other laminar organs. We show that cauline leaves display a significant delay in overall elongation compared to rosette leaves. Using live imaging, we reveal that their functional divergence hinges on early modulation of the timing of cell differentiation and cellular growth rates. In contrast to rosette leaves and sepals, cell differentiation is delayed in cauline leaves, fostering extended proliferation, prolonged morphogenetic activity, and growth redistribution within the organ. Notably, cauline leaf growth is transiently suppressed during the early stages, keeping the leaf small and unfolded during the initiation of the first flowers. Our findings highlight the unique developmental timing of cauline leaves, underlying their shift from an early protective role to a later photosynthetic function.

Senescence in Alveolar Epithelial Type II Cells Promotes Acute Lung Injury and Impairs Regeneration.

Mortality of acute lung injury (ALI) increases with age. Alveolar epithelial type 2 cells (AEII) are the progenitor cells of the alveolar epithelium and crucial for repair after injury. We hypothesize that telomere dysfunction-mediated AEII senescence impairs regeneration and promotes the development of ALI. To discriminate between the impact of old age and AEII senescence in ALI, young (3 months) and old (18 months) Sftpc-Ai9 mice and young Sftpc-Ai9-Trf1 mice with inducible Trf1 knockout-mediated senescence in AEII were treated with 1 µg lipopolysaccharide (LPS)/g BW (n=9-11). Control mice received saline (n=7). Mice were sacrificed 4 or 7 days later. Lung mechanics, pulmonary inflammation and proteomes were analyzed and parenchymal injury, AEII proliferation and AEI differentiation rate were quantified using stereology. Old mice showed 55% mortality by day 4, whereas all young mice survived. Pulmonary inflammation was most severe in old mice, followed by Sftpc-Ai9-Trf1 mice. Young Sftpc-Ai9 mice recovered almost completely by day 7, while Sftpc-Ai9-Trf1 mice still showed mild signs of injury. An expansion of AEII was only measured in young Sftpc-Ai9 mice at day 7. Aging and telomere dysfunction-mediated senescence had no impact on AEI differentiation rate in controls, but the reduced number of AEII in Sftpc-Ai9-Trf1 mice also affected de-novo differentiation after injury. In conclusion, telomere dysfunction-mediated AEII senescence promoted parenchymal inflammation in ALI, but did not enhance mortality like old age. While Differentiation rate remained functional with old age and AEII senescence, AEII proliferative capacity was impaired in ALI, affecting the regenerative ability.