Enhanced Cell Growth Research Articles

Baicalin alleviates LPS-induced cytotoxicity in acute lung injury through mediating METTL14/SOX6 axis.

Baicalin (C21H18O11) is a flavonoid component extracted from scutellaria baicalensis with biological activity in various types of diseases, including acute lung injury (ALI). The relevant mechanism behind baicalin in ALI needs further investigation. ALI model in vitro was established by lipopolysaccharide (LPS) in WI-38 cells (lung fibroblast). Cell growth was determined via MTT assay and EdU assay. Apoptosis was assessed using flow cytometry, caspase 3 assay and TUNEL assay. Oxidative indicators and inflammatory cytokines were detected by commercial kits. Interaction between methyltransferase-like 14 (METTL14) and SRY-Box Transcription Factor 6 (SOX6) was studied using Methylated RNA Immunoprecipitation (MeRIP) and dual-luciferase reporter assay. RT-qPCR and western blot were applied for examining gene levels. Baicalin enhanced cell growth and reduced apoptosis, oxidative stress, inflammation after ALI was induced by LPS. Downregulation of SOX6 weakened LPS-induced cytotoxicity in WI-38 cells. Baicalin prevented from LPS-induced lung cell injury via reducing SOX6 expression. SOX6 expression was stabilized by METTL14 through its methylation modification. METTL14/SOX6 axis was related to the regulation of baicalin in LPS-treated WI-38 cells. Therefore, baicalin played an important role to inhibit LPS-induced cytotoxicity in vitro via METTL14-mediated methylation of SOX6.

Production of Polyvinyl Alcohol/Amoxicillin – Chitosan/Collagen Hybrid Bilayer Membranes for Regeneration of Gingival Tissues

AbstractPeriodontal diseases, if untreated, can cause gum recession and tooth root exposure, resulting in infection and irreversible damage. Traditional treatments using autologous grafts are painful and often result in postoperative complications. Scaffolds offer a less invasive alternative, promoting cell proliferation and healing without additional surgery, thus enhancing comfort for patients and doctors. This study developed Chitosan (Chit)/Collagen (Col) film surfaces and drug‐loaded Polyvinyl Alcohol (PVA)/Amoxicillin (AMX) nanofibers using solvent casting and electrospinning methods, respectively. The surfaces are characterized by scanning electron microscopy (SEM), mechanical testing, Fourier Transform Infrared Spectroscopy (FTIR), and differential scanning calorimetry (DSC). Biocompatibility and antimicrobial properties are assessed using NIH/3T3 fibroblast cells and bacterial cultures. SEM images confirmed the structural integrity of AMX‐loaded 13% PVA nanofibers, while FTIR analysis validated the compositional integrity of PVA/AMX nanofibers and Chit/Col film hybrid surfaces. Cell studies showed over 90% viability for Chit/Col film + PVA/AMX nanofiber hybrid bilayer membranes, confirming their biocompatibility. The antimicrobial assessment indicated that the Chit/Col film + PVA/AMX (0.2%) nanofiber hybrid bilayer membrane exhibited superior efficacy against Streptococcus mutans. These findings suggest that this hybrid bilayer membrane can enhance cell growth, promote proliferation, and enable controlled drug release, offering significant promise for regeneration of gingival tissues.

Enhanced Cell Growth and Astaxanthin Production in Haematococcus lacustris by Mechanostimulation of Seed Cysts

The slow growth and complex life cycle of Haematococcus lacustris pose significant challenges for cost-effective astaxanthin production. This study explores the use of microfluidic collision treatment to stimulate the germination of dormant seed cysts, thereby improving photosynthetic cell growth and astaxanthin productivity in H. lacustris cultivated in well plate and flask cultures. The flow rate (1.0–3.0 mL/min) and the number of T-junction loops (3–30) were optimized in the microfluidic device. Under optimal conditions (a flow rate of 2.0 mL/min with 10 loops), the total cell number density in well plate cultures increased by 44.5% compared to untreated controls, reaching 28.9 ± 2.0 × 104 cells/mL after 72 h. In flask cultures, treated cysts showed a 21% increase in astaxanthin productivity after 30 d, reaching 0.95 mg/L/d, due to higher biomass concentrations, while the astaxanthin content per cell remained constant. However, excessive physical collision stress at higher flow rates and loop numbers resulted in reduced cell viability and cell damage. These findings suggest that carefully controlled cyst mechanostimulation can be an effective and environmentally friendly strategy for Haematococcus biorefining, enabling the production of multiple bioactive products.

Plasmid-encoded phosphatase RapP enhances cell growth in non-domesticated Bacillus subtilis strains.

The trade-off between rapid growth and other important physiological traits (e.g., survival and adaptability) poses a fundamental challenge for microbes to achieve fitness maximization. Studies on Bacillus subtilis biology often use strains derived after a process of lab 'domestication' from an ancestral strain known as Marburg strain. The domestication process led to loss of a large plasmid (pBS32) encoding a phosphatase (RapP) that dephosphorylates the Spo0F protein and thus regulates biofilm formation and sporulation. Here, we show that plasmid pBS32, and more specifically rapP, enhance growth rates by preventing premature expression of the Spo0F-Spo0A-mediated adaptive response during exponential phase. This results in reallocation of proteome resources towards biosynthetic, growth-promoting pathways without compromising long-term fitness during stationary phase. Thus, RapP helps B. subtilis to constrain physiological trade-offs and economize cellular resources for fitness improvement.

Catechin as a functional additive in electrospun PCL/gelatin/nHA nanocomposite fibers for tissue engineering applications

AbstractThe promise of polymeric nanocomposite fibers in the biomedical field is well‐documented due to their adjustable properties and versatility. Electrospun fiber mats, which mimic the extracellular matrix, are particularly noted for their potential in tissue regeneration and repair. In this study, we investigate the role of catechin, a flavonoid, in enhancing cellular response to electrospun nanocomposite fibers of polycaprolactone (PCL), gelatin, and nanohydroxyapatite (nHA). Nanocomposite fibers were fabricated with varying concentrations of catechin and comprehensive analyses of the composite fibers were performed to evaluate their structural and chemical properties. In vitro, assays were performed to examine cell viability and ascertain the influence of catechin on cellular responses to these nanocomposite fibers. Simultaneously, in vivo studies assessed tissue responses to these materials. The findings revealed that incorporating catechin into PCL/gelatin/nHA nanocomposite fibers improved cellular responses in vitro as demonstrated by enhanced cell viability. Furthermore, in vivo investigations displayed positive tissue responses with these fibers, indicating their capacity to enhance cell growth and accelerate tissue regeneration. This study elucidates the potential of catechin as an integral component in designing polymeric nanocomposite fibers, potentially broadening the scope of their biomedical applications.

The promotion of cell proliferation and invasion in cutaneous squamous cell carcinomas after ARNT downregulation is associated with CXCL3

The aryl hydrocarbon receptor nuclear translocator (ARNT) is a transcription factor associated with adaptive responses to cellular stress. Its role in cutaneous squamous cell carcinoma (cSCC) remains poorly understood. The aim of this study was to investigate the role of ARNT in cSCC. Immunohistochemistry revealed downregulation of ARNT in cSCC, precancerous lesions (actinic keratosis), and cells. Knockdown of ARNT in A431 and SCL-1 cells significantly enhanced cell growth and metastasis. Microarray analysis and Ingenuity Pathway Analysis confirmed that loss of ARNT in A431 cells was highly correlated with cell growth and movement and upregulated CXCL3 expression. Cellular and xenograft experiments further confirmed that ARNT regulates cSCC proliferation and invasiveness in a CXCL3-dependent manner. ARNT may regulate CXCL3 expression through ROS-STAT3 pathway. In conclusion, this study demonstrates that ARNT plays a critical role in the development of cSCC and significantly affects the proliferation and metastatic ability of cSCC cells. It has the potential to serve as an ideal treatment target for cSCC.

Four cyclometalated Ir(iii) complexes and insights into their luminescence, cytotoxicity and DNA/BSA binding performance.

Four cyclometalated Ir(iii) complexes based on 4'-p-N,N-bis(2-hydroxyethyl)benzyl-2,2':6',2''-terpyridine (TPYOH) and 4'-p-N,N-bis(2-hydroxyethyl)benzyl-6'-benzyl-2,2'-bipyridine (PhbpyOH) were synthesized and characterized. All the Ir(iii) complexes exhibited strong MLCT absorption peaks at about 450 nm, broad emission bands in the range of 500-700 nm. Z-scan results revealed that only complex Ir1A could exhibit certain two-photon absorption with maximal cross section values of 215 GM at 890 nm. When excited by 700-850 nm femtosecond laser, complex Ir1A gave a TPEF peak around 567 nm. All four complexes exhibited enhanced cell growth inhibitory activity against MCF-7 tumour cells under light irradiation comparing to their dark toxicity, with Ir1B showing the highest PI value (>50). The pathways and efficiencies of ROS generation by Ir(iii) complexes varied, with Ir2A being more effective in producing 1O2 while Ir1A mainly generating O2˙-. The Ir(iii) complexes undergo hydrogen bonding with DNA bases/phosphodiester through two O-H bonds on the bis(hydroxyethyl)amino group. The free pyridine-N atom in Ir1A forms additional hydrogen bond with DNA base, while the ligand TPYOH in Ir2A has better molecular planarity due to adopting {N, N, N} coordination mode, thus these two complexes show better DNA affinity. The complexes demonstrated weak interactions with BSA, through hydrogen bonding with amino acid residues at different regions of BSA molecule.

The role of cornulin (CRNN) in the progression of cutaneous squamous cell carcinoma involving AKT activation in SCL-1.

Cutaneous squamous cell carcinoma (cSCC) is the second most common non-melanoma skin cancer that has been on the rise in recent times, particularly among older individuals. Cornulin (CRNN) is increasingly recognized as an oncogene involved in developing various types of tumors. However, the precise contribution to cSCC remains unclear. Our study observed a significant increase in CRNN expression in cSCC samples compared to healthy skin. CRNN expression in the SCL-1 cell line derived from cSCC was reduced, leading to a halt in cell growth during the transition from the G1 phase to the S phase. This reduction inhibits cell division, promotes cell death, and decreases cell invasion and migration. CRNN overexpression has been found to enhance cell growth and prevent cells from undergoing natural cell death, and the cancer-promoting effects of CRNN are linked to AKT activation. Using a mouse xenograft model, we demonstrated that the inhibition of CRNN led to a decline in cSCC tumor growth in a living organism, providing evidence of CRNN's involvement in cSCC occurrence and development. This study establishes a foundation for evaluating the effectiveness of CRNN in treating cSCC, enabling further investigation in this area.

Development of an efficient pretreatment process and multi-functional acetate co-metabolism strategy for the treatment of high strength biogas slurry using a newly isolated Chlorella sorokiniana

The efficient treatment of biogas slurry (BS) to meet the government’s discharge standards is a major challenge for most livestock and poultry enterprises. Although microalgae-based wastewater treatment has many significant benefits over traditional technologies, the poor ammonium tolerance of regular algal species, the pH imbalance during microalgae cultivation, and the complex and expensive BS pretreatment process greatly limit its application in BS treatment. Aimed at these issues, this study firstly isolated a robust Chlorella sp. with strong ammonium and acidic tolerance, as well as heterotrophy ability. To facilitate optimal pH stability and growth enhancement, a co-metabolism cultivation strategy based on the addition of 0.1 g·L-1 acetate in the form of fed-batch was developed. In addition, an efficient pretreatment process integrating ammonia reduction by air stripping with turbidity and chromaticity reduction by acidic precipitation was developed for the elimination of inhibitory factors of microalgal growth in BS. The isolated Chlorella sp. was capable of growing in the pretreated real BS and no growth inhibition was observed even in the undiluted BS. The acetate co-metabolism cultivation strategy obviously enhanced cell growth and pollutant removal and both NH4+ and total phosphorus were reduced to meet the discharge standards of China via 2.5-fold dilutions of BS. The accumulation of high-value biomass could not only fully cover the cost of wastewater treatment, but also bring significant returns. The net profit from treating 1 m3 of BS reached $ 116.2. This study provides a simple and efficient packaged process for the treatment of high strength BS and is expected to greatly reduce the process cost of BS.

Development of in situ forming autologous fibrin scaffold incorporating synthetic teriparatide peptide for bone tissue engineering.

This study investigates the potential of an in-situ forming scaffold using a fibrin-based scaffold derived from autologous plasma combined with Synthetic Teriparatide (TP) for bone regeneration application. TP is known for its bone formation stimulation but has limited clinical use due to side effects. This autologous delivery system aims to provide precise, controlled, localized, and long-term release of TP for accelerating bone regeneration. Fibrinogen from autologous plasma was extracted using ethanol, and thrombin was precipitated with ammonium sulfate to create the fibrin scaffold. Characterization of fibrinogen was done through FTIR, SDS-Page, porosity, SEM, degradation, and rheology tests. Viability was assessed by MTT in five groups with different concentrations of TP in fibrin scaffold (50, 100, and 150 µl/ml), fibrin alone, and a control group against HEK and Wharton's jelly cells. The release profile of different concentrations of TP in the fibrin scaffold was also examined. The formation time of the fibrin scaffold was 4 ± 0.2 s. The highest Infrared absorption for fibrinogen was confirmed. Rheology assessment revealed a higher elastic modulus than the viscous modulus. The created fibrin scaffold displayed a consistent three-dimensional microstructure with an interconnected porous network. Cytotoxicity assays demonstrated good biocompatibility and enhanced cell growth with different concentrations of TP in the fibrin scaffold. The TP release increased with higher concentrations, peaking at an average of 61% over 54 h. Autologous plasma-derived fibrin scaffolds incorporating TP exhibit satisfactory release within the scaffold and hold promise as a versatile bone filler for clinical use, facilitating osteoregeneration.

Reduced aggregation of the Leghorn Male Hepatoma (LMH) cell line in suspension by supplementing dextran sulfate in the media.

The study aimed to improve the efficiency of Leghorn Male Hepatoma (LMH) cells for animal virus vaccine production by transitioning from adherent to suspension culture and evaluating the effects of dextran sulfate (DS) on preventing cell aggregation. The goal was to enhance cell growth, viability, and glucose metabolism and to develop efficient suspension-adapted LMH cells for large-scale vaccine production. LMH cells previously cultured in an adherent state were transferred to 125 mL Erlenmeyer flasks to conduct suspension culture. Cell culture performance, including cell density, viability, and glucose metabolism, during the cultures was measured, along with an assessment of cell aggregation. Additionally, mRNA expression levels of genes associated with cell adhesion and apoptosis were monitored. DS supplementation in suspension culture enhanced cell viability and growth, with higher cell densities and viabilities compared to control media. Additionally, DS supplementation reduced glucose consumption and waste production, indicating improved metabolic efficiency. DS also delayed cell aggregation, possibly by downregulating integrin expression and promoting anti-apoptotic gene expression. However, even after 2 months, cell aggregation persisted in both control and DS-supplemented cultures, suggesting further optimization is needed for LMH cell adaptation to suspension culture. DS supplementation in LMH cell suspension cultures led to notable improvements in cell growth, viability, and glucose metabolism, while also decreasing the cell aggregation.

Metabolic Engineering of High L-Lysine-Producing Escherichia coli for de Novo Production of L-Lysine-Derived Compounds.

5-Aminovalerate (5-AVA), 5-hydroxyvalerate (5-HV), and 1,5-pentanediol (1,5-PDO) are l-lysine derivatives with extensive applications in the production of materials such as polyesters, polyurethane, plasticizers, inks, and coatings. However, their large-scale production is limited by the lack of efficient synthetic pathways. Here, we aimed to construct multiple synthetic pathways by screening the key enzymes involved in the synthesis of these compounds in Escherichia coli. The engineered pathway utilizing RaiP demonstrated a superior catalytic efficiency. The LER strain that overexpressed only raiP successfully synthesized 9.70 g/L 5-HV and 8.31 g/L 5-AVA, whereas the strain LERGY that overexpressed raiP, gabT, and yahK accumulated 9.72 g/L 5-HV and 7.95 g/L 5-AVA from 20 g/L glucose. The introduction of exogenous transaminases and dehydrogenases enhanced cell growth and fermentation efficiency with respect to 5-HV synthesis, albeit without significantly impacting the yield. Strain LE05, incorporating only two exogenous enzymes, RaiP and CaR, produced 1.87 g/L 1,5-PDO, 3.85 g/L 5-HV, and 4.78 g/L 5-hydroxyglutaraldehyde from 20 g/L glucose after 6 days. The strain LE02G, fortified with transaminase, dehydrogenase, and NADPH regeneration system, accumulated 7.82 g/L 1,5-PDO, whereas the aldp-knock out LE02G2 synthesized 10.98 g/L 1,5-PDO from 50 g/L glucose in fed-batch fermentation after 6 days, yielding 0.22 g/g glucose (0.37 mol/mol). Introducing the NADPH regeneration pathway and deleting the NADPH-consuming pathways increased the 1,5-PDO yield and decreased the precursor concentration. The proposed pathways and engineering strategies presented in this study can prove instrumental in developing biological routes for the practical production of 5-AVA, 5-HV, and 1,5-PDO.

Parallel metabolic pathway engineering for aerobic 1,2-propanediol production in Escherichia coli.

The demand for the essential commodity chemical 1,2-propanediol (1,2-PDO) is on the rise, as its microbial production has emerged as a promising method for a sustainable chemical supply. However, the reliance of 1,2-PDO production in Escherichia coli on anaerobic conditions, as enhancing cell growth to augment precursor availability remains a substantial challenge. This study presents glucose-based aerobic production of 1,2-PDO, with xylose utilization facilitating cell growth. An engineered strain was constructed capable of exclusively producing 1,2-PDO from glucose while utilizing xylose to support cell growth. This was accomplished by deleting the gloA, eno, eda, sdaA, sdaB, and tdcG genes for 1,2-PDO production from glucose and introducing the Weimberg pathway for cell growth using xylose. Enhanced 1,2-PDO production was achieved via yagF overexpression and disruption of the ghrA gene involved in the 1,2-PDO-competing pathway. The resultant strain, PD72, produced 2.48±0.15gL-1 1,2-PDO with a 0.27±0.02gg-1-glucose yield after 72h cultivation. Overall, this study demonstrates aerobic 1,2-PDO synthesis through the isolation of the 1,2-PDO synthetic pathway from the tricarboxylic acid cycle.

Feasibility study on heterotrophic utilization of galactose by Chlorella sorokiniana and promotion of galactose utilization through mixed carbon sources culture

BackgroundThe development of alternative carbon sources is important for reducing the cost of heterotrophic microalgae cultivation. Among cheap feedstocks, galactose is one of the most abundant sugars and can be easily obtained from many natural biomasses. However, it is generally difficult to be utilized by microalgae. In addition, the mechanism of its low utilization efficiency in heterotrophic cultivation is still unknown.ResultsAmong seven tested carbon sources, only glucose and acetate could be efficiently utilized by C. sorokiniana in heterotrophic cultivation while there were no apparent signs of utilization of other carbohydrates, including galactose, in regular heterotrophic cultivation. However, galactose could be utilized in cultures with high inoculation sizes. This confirmed that C. sorokiniana has a complete pathway for transporting and assimilating galactose under dark conditions, but the rate of galactose utilization is quite low. In addition, the galactose utilization was greatly enhanced in mixotrophic cultures, which indicated that galactose utilization could be enhanced by additional pathways that can enhance cell growth. Based on above results, a mixed carbon source culture strategy was proposed to improve the utilization rate of galactose, and a significant synergistic effect on cell growth was achieved in cultures using a mixture of galactose and acetate.ConclusionsThis study indicated that the galactose metabolism pathway may not be inherently deficient in Chlorophyta. However, its utilization rate was too low to be detected in regular heterotrophic cultivation. Mixed carbon source culture strategy was confirmed effective to improve the utilization rate of galactose. This study contributes to a deeper understanding of the utilization ability of difficultly utilized substrates in the heterotrophic cultivation of microalgae, which is of great significance for reducing the cost of heterotrophic cultivation of microalgae.

Comparative evaluation on surface nanohardness, surface microhardness, surface roughness, and wettability of plant-based organic nanoparticle reinforced polyetheretherketone as an implant material - An in vitro study.

Synthetic inorganic materials are commonly used as reinforcing agents in polyetheretherketone (PEEK) composite, whereas natural organic plant-based reinforcing agents are negligible. Surface hardness, roughness, and wettability are indicative factors of osseointegration behavior to be used as an implant material. This study evaluated micro surface hardness (MSH), nano surface hardness (NSH), surface roughness (SR), and contact angle (CA) of PEEK-Azadirachta indica reinforced at 10 wt%, 20 wt%, and 30 wt%. This was an in vitro study. Neem (A. indica) leaf nanoparticles were prepared and reinforced with PEEK powder at 10%, 20%, and 30% weight ratios by injection molding. Sixty specimens underwent the microhardness and CA testing using a digital microhardness tester, and CA goniometer, respectively, and later nanoindentation test to analyze the nanohardness and SR. A one-way ANOVA test with a 95% confidence interval for MSH and NSH, SR, and CA was performed on the samples. A post hoc Bonferroni test was conducted (α = 0.05) to compare the groups. There was a significant increase in nanohardness (P = 0.000) with zero difference in microhardness (P = 0.514). The addition of 10 wt%, 20 wt%, and 30 wt% nanoparticles increased the SR value of the pure PEEK from 273.19 nm to 284.10 (3.99%), 296.91 (8.68%), and 287.54 (5.24%), respectively. In the analysis of the CA, CA 20% shows the lowest angle (63.69) with the highest for control specimens (82.39). There is an increase in the PEEK composite SR with a decrease in CA. The addition of plant-derived nanoparticles into the PEEK matrix has a significant impact on the hardness and hydrophobicity enhancing cell growth and osteoblastic differentiation during osseointegration of dental implants.

Long non-coding RNA DARS-AS1 facilitates breast cancer progression by modulating the miR-6835-3p/ATF3 axis

Long non-coding RNAs (lncRNAs) play crucial roles in various cellular processes associated with cancer progression, including invasion, proliferation, and metastasis. Despite this understanding, the specific role of DARS-AS1 in breast cancer remains underexplored. In this study, we employed quantitative reverse transcription-polymerase chain reaction to measure the expression levels of DARS-AS1 and miR-6835-3p. Functional assessments, including the cell invasion and CCK-8 assays, were conducted to investigate cellular behaviors. In addition, a luciferase reporter assay was employed to elucidate the mechanistic interaction between DARS-AS1 and miR-6835-3p. Notably, DARS-AS1 expression was elevated in breast cancer cell lines (MCF7 and MDA-MB-231) relative to the non-cancerous MCF-10A cells. Overexpression of DARS-AS1 enhanced cell growth and invasion in MDA-MB-231 breast cancer cells. Further investigation revealed that DARS-AS1 acts as a sponge for miR-6835-3p in breast cancer cells. Overexpression of miR-6835-3p inhibited luciferase activity, specifically in the presence of wild-type DARS-AS1, highlighting a direct interaction. Ectopic expression of DARS-AS1 suppressed miR-6835-3p in MDA-MB-231 cells. Concurrently, miR-6835-3p levels were downregulated in breast cancer cells, and miR-6835-3p exhibited a negative correlation with DARS-AS1 expression. Mechanistically, miR-6835-3p targeted ATF3 expression in breast cancer cells. Increased levels of DARS-AS1 were found to enhance cellular proliferation and invasion by modulating ATF3. Our findings indicate that DARS-AS1 acts as an oncogene in breast cancer, partially through regulation of the miR-6835-3p/ATF3 pathway. This study provides valuable insights into the molecular mechanisms contributing to breast cancer progression, offering potential targets for therapeutic interventions.

Optimization and investigation of Physical, chemical, and biological properties of nanofibers produced from (poly glycerol Sebacate-co-caprolactone)/gelatin/peptide and scaffold’s cellular behavior

Recently, peptide and Poly(Glycerol Sebacat) PGS-based materials have garnered significant attention in tissue engineering. In this study, we synthesized two novel nanofibrous webs, namely Poly (glycerol sebacate)/gelatin/peptide (PGS/Gel/PT) and Poly (glycerol sebacate co caprolactone)/gelatin/peptide (P(GScoCL)/Gel/PT), utilizing the electrospinning technique with acetic acid as a cost-effective and eco-friendly solvent. To optimize the diameter of the electrospun nanofibrous samples, we employed response surface methodology and artificial neural network, investigating the impact of various electrospinning parameters. Nanofibrous webs with a diameter of 232 nm under the optimized conditions. Nanofibers were characterized using FTIR, DSC, contact angle measurement, and mechanical testing. The biological properties including biodegradability, cell adhesion, MTT assay, and antibacterial efficacy were performed. Nanofibrous samples antibacterial activity, displaying 99% effectiveness against both Gram-positive and Gramnegative bacteria. Moreover, in-vitro studies on the cellular proliferation of human Mesenchymal Stem Cells (hMSCs) nanofiber scaffold demonstrated normal cell morphology and significantly enhanced cell growth after 4 days.

Development of functionalized poly(lactide) films with chitosan via SI-SARA ATRP as scaffolds for neuronal cell growth

Polylactic acid (PLA), a polymer derived from renewable resources, is gaining increasing attention in the development of biomedical devices due to its cost-effectiveness, low immunogenicity, and biodegradability. However, its inherent hydrophobicity remains a problem, leading to poor cell adhesion features. On this basis, the aim of this work was to develop a method for functionalizing the surface of PLA films with a biopolymer, chitosan (CH), which was proved to be a material with intrinsic cell adhesive properties, but whose mechanical properties are insufficient to be used alone. The combination of the two polymers, PLA as a bulk scaffold and CH as a coating, could be a promising combination to develop a scaffold for cell growth. The modification of PLA films involved several steps: aminolysis followed by bromination to graft amino and then bromide groups, poly(glycidyl methacrylate) (PGMA) grafting by surface-initiated supplemental activator and reducing agent atom transfer radical polymerization (SI-SARA ATRP) and finally the CH grafting. To prove the effective adhesive properties, conjugated and non-conjugated films were tested in vitro as substrates for neuronal cell growth using differentiated neurons from human induced pluripotent stem cells. The results demonstrated enhanced cell growth in the presence of CH.

Silk fibroin promotes H3K9me3 expression and chromatin reorganization to regulate endothelial cell proliferation.

Silk fibroin (SF), which is extensively utilized in tissue engineering and vascular grafts for enhancing vascular regeneration, has not been thoroughly investigated for its epigenetic effects on endothelial cells (EC). This study employed RNA sequencing analysis to evaluate the activation of histone modification regulatory genes in EC treated with SF. Subsequent investigations revealed elevated H3K9me3 levels in SF-treated EC, as evidenced by immunofluorescence and western blot analysis. The study utilized H2B-eGFP endothelial cells to demonstrate that SF treatment results in the accumulation of H2B-marked chromatin in the nuclear inner cavities of EC. Inhibition of H3K9me3 levels by a histone deacetylase inhibitor TSA decreased cell proliferation. Furthermore, the activation of the MAPK signaling pathway using chromium picolinate decreased the proliferative activity and H3K9me3 level in SF-treated EC. SF also appeared to enhance cell growth and proliferation by modulating the H3K9me3 level and reorganizing chromatin, particularly after oxidative stress induced by H2O2 treatment. In summary, these findings indicate that SF promotes EC proliferation by increasing the H3K9me3 level even under stress conditions.

RUNX1-induced upregulation of PTGS2 enhances cell growth, migration and invasion in colorectal cancer cells

Colorectal cancer (CRC) arises via the progressive accumulation of dysregulation in key genes including oncogenes and tumor-suppressor genes. Prostaglandin-endoperoxide synthase 2 (PTGS2, also called COX2) acts as an oncogenic driver in CRC. Here, we explored the upstream transcription factors (TFs) responsible for elevating PTGS2 expression in CRC cells. The results showed that PTGS2 silencing repressed cell growth, migration and invasion in HCT116 and SW480 CRC cells. The two fragments (499–981 bp) and (1053–1434 bp) were confirmed as the core TF binding profiles of the PTGS2 promoter. PTGS2 expression positively correlated with RUNX1 level in colon adenocarcinoma (COAD) samples using the TCGA-COAD dataset. Furthermore, RUNX1 acted as a positive regulator of PTGS2 expression by promoting transcriptional activation of the PTGS2 promoter via the 1086–1096 bp binding motif. In conclusion, our study demonstrates that PTGS2 upregulation induced by the TF RUNX1 promotes CRC cell growth, migration and invasion, providing an increased rationale for the use of PTGS2 inhibitors in CRC prevention and treatment.