Search Results (48)

Neural stem/progenitor cells (NSPCs) in the subventricular zone (SVZ) of the central nervous system (CNS) are critical for tissue repair following injury or disease. These cells retain the capacity to proliferate, migrate, and differentiate into neurons, astrocytes, and oligodendrocytes, making them a promising therapeutic target for neurodegenerative disorders and traumatic injuries. However, the molecular mechanisms regulating their proliferation remain incompletely understood. This study investigates the role of cAMP responsive element-binding protein 5 (CREB5) in the proliferation of rat SVZ-derived NSPCs and elucidates its regulatory mechanism. Using RNA interference, we demonstrated that CREB5 knockdown significantly reduced cell viability, neurosphere formation capacity, and the number of proliferating cells (BrdU- and Ki-67-positive cells) both in vitro and in vivo. In contrast, CREB5 overexpression played opposing roles in cell proliferation. Additionally, alteration of CREB5 expression did not affect apoptosis, as assessed by TUNEL staining, indicating a specific role in proliferation rather than in cell death. Mechanistically, we identified Nuclear Factor One X (NFIX) as a transcriptional target of CREB5. CREB5 binds to the AP-1 site in the NFIX promoter, enhancing its expression. CREB5 knockdown inhibited NFIX expression, while CREB5 overexpression exerted the opposite function. ChIP and luciferase reporter assays further confirmed that CREB5 directly regulates NFIX promoter activity. More importantly, alteration of NFIX expression could reverse the effect of CREB5 on NSPC proliferation. These findings highlight CREB5 as a key regulator of NSPC proliferation through its interaction with NFIX, providing a potential therapeutic target for stem cell-based treatments of CNS disorders. Full article

Articular cartilage (AC) has a very limited capacity for self-healing once damaged. Chondrocytes maintain AC homeostasis and are key cells in AC tissue engineering (ACTE). However, chondrocytes lose their function due to oxidative stress. Umbilical cord mesenchymal stem cells (UCMSCs) are investigated as an alternative cell source for ACTE. MSCs are known to regulate tissue regeneration through host cell modulation, largely via extracellular vesicle (EV)-mediated cell-to-cell communication. The purpose of this study was to verify whether UCMSC-derived EVs (UCMSC-EVs) enhance chondrocyte function. The mean particle sizes of the UCMSC-EVs were 79.8 ± 19.05 nm. Transmission electron microscopy (TEM) revealed that UCMSC-EVs exhibited a spherical morphology. The presence of CD9, CD63, and CD81 confirmed the identity of UCMSC-EVs, with α-tubulin undetected. UCMSC-EVs maintained chondrocyte survival, and increased chondrocyte proliferation after intake by chondrocytes. UCMSC-EVs upregulated mRNA levels of SOX-9, collagen type II (Col-II), and Aggrecan, while decreasing collagen type I (Col-I) levels. UCMSC-EVs reduced the oxidative stress of chondrocytes by reducing mitochondrial superoxide production and increasing protein levels of SOD-2 and Sirt-3 in chondrocytes. The 50 most abundant known microRNAs (miRNAs) derived from UCMSC-EVs were selected for gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. GO analysis revealed enrichment in pathways associated with small GTPase-mediated signal transduction, GTPase regulatory activity, and mitochondrial matrix. The KEGG analysis indicated that these miRNAs may regulate chondrocyte function through the PI3K-Akt, MAPK, and cAMP signaling pathways. In summary, this study shows that UCMSC-EVs enhance chondrocyte function and may be applied to ACTE. Full article

Interventions have been designed to close achievement gaps in Science, Technology, Engineering, and Math (STEM) disciplines and to remedy the “leaky STEM pipeline”. However, there has been little focus on designing complementary interventions that seek to broaden the youth population who “enter the STEM pipeline”. The current work aims to broaden STEM engagement in youth by developing a STEM intervention using unrecognized forms of cultural capital. These novel, basketball-based interventions were designed to engage a naturally occurring population of youth with pre-existing interest in sports but low levels of pre-existing STEM interest, ranging from the 2nd to the 12th grades. These interventions utilized sports as a venue for informal STEM learning across three variations: a single-hour event, a one-day clinic, and a multi-day camp. Participants’ interest in pursuing a STEM career significantly increased across all three variations of the STEM intervention. Notably, these effect sizes were descriptively larger for programs of longer duration and were significantly stronger for students who reported playing basketball prior to the program. The current work introduces a novel STEM education intervention that has been shown to be repeatedly successful in utilizing students’ pre-existing interest in sports as a bridge to STEM engagement. Full article

The underrepresentation of women in science fields limits their potential in solving current global challenges. As a lighthouse to close this gender gap, role models are crucial for girls to build their science identity, even in their early years. Therefore, we describe a combined mentoring intervention taking place during scientific summer camps for girls. In these camps, young girls lived for a week undertaking an intensive program conducting cutting-edge research and in close contact with female mentors and other girls within a community of practice. They were mentored in small groups, but there were also chances for participating in talks, entrepreneurial workshops, and social activities all together. On the last day, the girls presented their research results, sharing their perceptions about the camp and their concerns regarding the role of women in science in an open-door final conference. By means of a mixed-method assessment conceptualization, the aim of this study is to provide evidence supporting the impact of non-formal education settings to effectively enhance girls’ science potential by using inspiring female scientists acting as mentors and role models. Furthermore, the study intends to shed light on what were regarded to be the key factors of the camp design that had such an impact on the participating girls. In particular, the findings demonstrate that the participating girls improved their attitudes towards STEM after the camp, highlighting how role models, in several roles, were key to empowering them in science through the building of a gender-responsive and inclusive community. Finally, the paper also discusses the key elements of the intervention based on the lessons learned and its transferability to different educational contexts in order to expand the beneficial effects of a gender-sensitive science education to build an inclusive future. Full article

Background: Colorectal cancer (CRC) is characterized by the uncontrolled growth of malignant colonic or rectal crypt epithelium. About 85% of CRCs evolve through a stepwise progression from advanced precancerous adenoma lesions. A better understanding of the evolution from adenoma to carcinoma can provide a window of opportunity not only for early detection and therapeutic intervention but potentially also for cancer prevention strategies. Methods: This study investigates the heterogeneous methylation, copy-number alteration (CNA), and mutation signals of histological adenoma subtypes in the context of progression from normal colon to advanced precancerous lesions (APLs) and early-stage CRC. Results: Differential methylation analysis revealed 2321 significantly altered regions among APLs: 137 hypermethylated regions in serrated vs. tubular, 2093 in serrated vs. tubulovillous, and 91 in tubular vs. tubulovillous adenoma subtypes. The most differentiating pathways for serrated adenomas belonged to cAMP signaling and the regulation of pluripotency of stem cells, while regions separating tubular and tubulovillous subtypes were enriched for WNT signaling. CNA events were mostly present in tubular or tubulovillous adenomas, with the most frequent signals being seen in chromosomes 7, 12, 19, and 20. In contrast, early-stage CRC exhibited signals in chromosomes 7, 8, and 20, indicating different processes between APL and early-stage CRC. Mutations reinforce subtype-level differences, showing specific alterations in each subtype. Conclusions: These findings are especially important for developing early detection or cancer prevention tests trying to capture adenoma signatures. Full article

This study reports on an integrated steM camp that aimed to improve middle school students’ STEM identity, interest in STEM careers, and interest in environmental issues. Conjecture mapping was used as a tool to design the camp and to investigate if, how, and why the program features influenced the mediating processes and if, how, and why the mediating processes influenced the program outcomes. This study is grounded in design-based research and uses data from observations, interviews, surveys, facilitator reflections, and a group interview to answer the research questions. The findings revealed that most of the program features facilitated the intended mediating processes, which in turn influenced the intended outcomes. We also found that participants’ interest in STEM careers, interest in environmental issues, and interest in STEM identity increased. The findings of this study and the revised conjecture map advance the field’s understanding of how to improve middle school students’ STEM-related outcomes through an integrated steM camp. The findings also speak to some of the challenges of this designed environment and provide recommendations to address those challenges. Full article

This study reports on a STEM camp that aimed to engage middle grade students in computational thinking dispositions. Case study methodology and data from observational field notes and participant reflections were used to investigate if and how students engaged in computational thinking dispositions as they engaged in the unplugged LEGO activities. The findings revealed that unplugged structured LEGO activities (a) did not facilitate tolerance for ambiguity, (b) facilitated high persistence on difficult problems, and (c) high and developing willingness to collaborate with others to achieve a common goal. The findings also revealed that unplugged semi-structured LEGO activities (a) facilitated high and developing tolerance for ambiguity, (b) facilitated no evidence of persistence, and (c) increased and developed willingness to collaborate with others to achieve a common goal. The overall findings of this study suggest that when using unplugged, LEGO activities: (a) it is better to use unplugged structured LEGO activities to promote the computational thinking disposition of persistence, (b) it is better to use semi-structured activities to promote tolerance for ambiguity, and (c) it is better to use either or both to promote collaboration with others to achieve a common goal. The study’s findings are significant because it provides an empirical example of how the use of LEGOS as an unplugged activity can be used to facilitate computational thinking dispositions in middle grade students. Having this information is important because it can support STEM educators in modifying and adapting unplugged LEGO activities to develop students’ computational thinking dispositions. Full article

Diabetes mellitus (DM) is a global health concern with a rising incidence, particularly in aging populations and those with a genetic predisposition. Over time, DM contributes to various complications, including nephropathy, retinopathy, peripheral arterial disease (PAD), and neuropathy. Among these, diabetic neuropathy and PAD stand out due to their high prevalence and significant impact on patients’ quality of life. Diabetic distal symmetric polyneuropathy, the most common form of diabetic neuropathy, is driven by neuroinflammation stemming from prolonged hyperglycemia. Simultaneously, hyperglycemia significantly increases the risk of PAD, a condition further exacerbated by factors like smoking, age, and sedentary lifestyles. PAD frequently manifests as claudication, a debilitating symptom marked by pain and cramping during physical activity, which limits mobility and worsens patients’ outcomes. Cilostazol, a phosphodiesterase-3 inhibitor, has proven effective in managing intermittent claudication in PAD by improving walking distances and enhancing blood flow. Recent studies have also explored its potential benefits for diabetic neuropathy. Cilostazol’s mechanisms include vasodilation, platelet inhibition, and increased cyclic adenosine monophosphate (cAMP) levels, which may contribute to improved neurological outcomes. However, variability in the clinical evidence due to inconsistent treatment protocols highlights the need for further investigation. This review explores cilostazol’s mechanisms of action and therapeutic applications for managing neuropathy and PAD in diabetic patients, aiming to provide insights into its potential as a dual-purpose pharmacological agent in this high-risk population. Full article

Digital platforms are increasingly prevalent among young students in K-12 education, offering significant opportunities but also raising concerns about their effects on self-assessment and academic performance. This study investigates the effectiveness of Kahoot! compared to traditional instructional methods in enhancing mathematics achievement and its impact on multiple screen addiction (MSA) among Greek students aged 9 to 12 during a STEM summer camp. A quasi-experimental design was employed with a purposefully selected sample of one hundred and ten (n = 110) students, who were non-randomly divided into two groups: (a) an experimental group of fifty-five students (n = 55) who engaged with Kahoot! (using dynamic visual aids and interactive content) and (b) a control group of fifty-five students (n = 55) who received traditional instruction (using digital textbooks and PowerPoint slides with multimedia content) on laptops and tablets. The findings revealed a statistically significant difference in MSA scores, with the experimental group exhibiting lower MSA scores compared to their counterparts, indicating a positive impact on reducing screen addiction levels. While Kahoot! led to lower MSA levels, it significantly improved overall mathematical achievement, with a substantial effect size, suggesting a strong positive impact on learning outcomes. The current study highlights the importance of aligning educational tools with the intended outcomes and recommends further research to explore the broader impact of gamified learning on student engagement, screen addiction, and learning outcomes. Full article

In recent years, inducing pluripotent stem cells to differentiate into functional primordial germ cells (PGCs) in vitro has become an important method of obtaining a large number of PGCs. However, the instability and low induction efficiency of the in vitro PGC induction system restrict the application of PGCs in transgenic animal production, germplasm resource conservation and other fields. In this study, we successfully established a two-step induction model of chicken PGCs in vitro, which significantly improved the formation efficiency of PGC-like cells (PGCLCs). To further improve the PGC formation efficiency in vitro, 5025 differentially expressed genes (DEGs) were obtained between embryonic stem cells (ESCs) and PGCs through RNA-seq. GO and KEGG enrichment analysis revealed that signaling pathways such as BMP4, Wnt and Notch were significantly activated during PGC formation, similar to other species. In addition, we noted that cAMP was activated during PGC formation, while MAPK was suppressed. Based on the results of our analysis, we found that the PGC formation efficiency was significantly improved after activating Wnt and inhibiting MAPK, and was lower than after activating cAMP. To sum up, in this study, we successfully established a two-step induction model of chicken PGCs in vitro with high PGC formation efficiency, which lays a theoretical foundation for further demonstrating the regulatory mechanism of PGCs and realizing their specific applications. Full article

Skin mast cells (MCs) are critical effector cells in acute allergic reactions, and they contribute to chronic dermatoses like urticaria and atopic and contact dermatitis. KIT represents the cells‘ crucial receptor tyrosine kinase, which orchestrates proliferation, survival, and functional programs throughout the lifespan. cAMP response element binding protein (CREB), an evolutionarily well-conserved transcription factor (TF), regulates multiple cellular programs, but its function in MCs is poorly understood. We recently reported that CREB is an effector of the SCF (Stem Cell Factor)/KIT axis. Here, we ask whether CREB may also act upstream of KIT to orchestrate its functioning. Primary human MCs were isolated from skin and cultured in SCF+IL-4 (Interleukin-4). Pharmacological inhibition (666-15) and RNA interference served to manipulate CREB function. We studied KIT expression using flow cytometry and RT-qPCR, KIT-mediated signaling using immunoblotting, and cell survival using scatterplot and caspase-3 activity. The proliferation and cycle phases were quantified following BrdU incorporation. Transient CREB perturbation resulted in reduced KIT expression. Conversely, microphthalmia transcription factor (MITF) was unnecessary for KIT maintenance. KIT attenuation secondary to CREB was associated with heavily impaired KIT functional outputs, like anti-apoptosis and cell cycle progression. Likewise, KIT-elicited phosphorylation of ERK1/2 (Extracellular Signal-Regulated Kinase 1/2), AKT, and STAT5 (Signal Transducer and Activator of Transcription) was substantially diminished upon CREB inhibition. Surprisingly, the longer-term interference of CREB led to complete cell elimination, in a way surpassing KIT inhibition. Collectively, we reveal CREB as non-redundant in MCs, with its absence being incompatible with skin MCs’ existence. Since SCF/KIT regulates CREB activity and, vice versa, CREB is required for KIT function, a positive feedforward loop between these elements dictates skin MCs’ fate. Full article

Informal science education researchers have become increasingly interested in how out-of-school spaces that offer STEM (science, technology, engineering, and math) programs inform learners’ STEM achievement, interests, and affective outcomes. Studies have found that these spaces can offer critical learning and developmental opportunities for underrepresented racially minoritized (URM) students (Black, Latinx, low socioeconomic status) in STEM subjects. Shifting away from the leaky STEM pipeline analogy, researchers have posited contemporary understandings to explain why the minoritization of URM girls persists. Informal learning environments such as STEM summer camps are being studied to assess how URM girls experience and interact with STEM in novel ways. These environments can inform the research field about how URM girls’ perceptions of their STEM identities, abilities, efficacy, and belonging in STEM develop as they engage in those spaces. This mixed-method study used a multiple-case-study approach to examine how aspects of URM middle school girls’ STEM identities positively changed after participating in a one-week, sleep-away, single-gender STEM summer camp held at a university in the Southwestern U.S. Drawing on intersectionality and STEM identity, we used ecological systems theory to design our research study, examining how URM middle school girls narrate their STEM identities in this informal learning environment. Using quantitative analyses and deductive coding methods, we explored how elements of girls’ STEM identities were shaped during and after their participation in the STEM summer camp. Findings from our study highlight (1) quantitative changes in girl participants’ STEM identities, sense of belonging in STEM, and perceived STEM ability belief, (2) qualitative results supporting our quantitative findings, and (3) how the intersectionality of participants’ race and gender played a role in their STEM identities. This study points to the potential of STEM informal learning camps as a way of developing and fostering URM girls’ STEM identities. Full article

Clonostachys rosea is an excellent biocontrol fungus against numerous fungal plant pathogens. The cAMP signaling pathway is a crucial signal transduction pathway in fungi. To date, the role of the cAMP signaling pathway in C. rosea mycoparasitism remains unknown. An adenylate cyclase-encoding gene, crac (an important component of the cAMP signaling pathway), was previously screened from C. rosea 67-1, and its expression level was dramatically upregulated during the C. rosea mycoparasitization of the sclerotia of Sclerotinia sclerotiorum. In this study, the function of crac in C. rosea mycoparasitism was explored through gene knockout and complementation. The obtained results show that the deletion of crac influenced the growth rate and colony morphology of C. rosea, as well as the tolerance to NaCl and H₂O₂ stress. The mycoparasitic effects on the sclerotia of S. sclerotiorum and the biocontrol capacity on soybean Sclerotinia stem rot in ∆crac-6 and ∆crac-13 were both attenuated compared with that of the wild-type strain and complementation transformants. To understand the regulatory mechanism of crac during C. rosea mycoparasitism, transcriptomic analysis was conducted between the wild-type strain and knockout mutant. A number of biocontrol-related genes, including genes encoding cell wall-degrading enzymes and transporters, were significantly differentially expressed during C. rosea mycoparasitism, suggesting that crac may be involved in C. rosea mycoparasitism by regulating the expression of these DEGs. These findings provide insight for further exploring the molecular mechanism of C. rosea mycoparasitism. Full article

Background: Mesenchymal stem cells (MSCs) are pluripotent stromal cells that are among the most appealing candidates for regenerative medicine and may aid in the repair and regeneration of skeletal disorders through multiple mechanisms, including angiogenesis, differentiation, and response to inflammatory conditions. Tauroursodeoxycholic acid (TUDCA) has recently been used in various cell types as one of these drugs. The mechanism of osteogenic differentiation by TUDCA in hMSCs remains unknown. Methods: Cell proliferation was performed by the WST-1 method, and alkaline phosphatase activity and alizarin red-sulfate staining were used to confirm the osteogenic differentiation indicator. Expression of genes related to bone differentiation and specific genes related to signaling pathways was confirmed by quantitative real-time polymerase chain reaction. Results: We found that cell proliferation was higher as the concentration increased, and showed that the induction of osteogenic differentiation was significantly enhanced. We also show that osteogenic differentiation genes were upregulated, with the expression of the epidermal growth factor receptor (EGFR) and cAMP responsive element binding protein 1 (CREB1) being specifically high. To confirm the participation of the EGFR signaling pathway, the osteogenic differentiation index and expression of osteogenic differentiation genes were determined after using an EGFR inhibitor. As a result, EGFR expression was remarkably low, and that of CREB1, cyclin D1, and cyclin E1 was also significantly low. Conclusions: Therefore, we suggest that TUDCA-induced osteogenic differentiation of human MSCs is enhanced through the EGFR/p-Akt/CREB1 pathway. Full article

Currently, there are three major assaying methods used to validate in vitro whitening activity from natural products: methods using mushroom tyrosinase, human tyrosinase, and dopachrome tautomerase (or tyrosinase-related protein-2, TRP-2). Whitening agent development consists of two ways, melanin synthesis inhibition in melanocytes and downregulation of melanocyte stimulation. For melanin levels, the melanocyte cell line has been used to examine melanin synthesis with the expression levels of TRP-1 and TRP-2. The proliferation of epidermal surfaced cells and melanocytes is stimulated by cellular signaling receptors, factors, or mediators including endothelin-1, α-melanocyte-stimulating hormone, nitric oxide, histamine, paired box 3, microphthalmia-associated transcription factor, pyrimidine dimer, ceramide, stem cell factors, melanocortin-1 receptor, and cAMP. In addition, the promoter region of melanin synthetic genes including tyrosinase is upregulated by melanocyte-specific transcription factors. Thus, the inhibition of growth and melanin synthesis in gene expression levels represents a whitening research method that serves as an alternative to tyrosinase inhibition. Many researchers have recently presented the bioactivity-guided fractionation, discovery, purification, and identification of whitening agents. Melanogenesis inhibition can be obtained using three different methods: tyrosinase inhibition, copper chelation, and melanin-related protein downregulation. There are currently four different types of inhibitors characterized based on their enzyme inhibition mechanisms: competitive, uncompetitive, competitive/uncompetitive mixed-type, and noncompetitive inhibitors. Reversible inhibitor types act as suicide substrates, where traditional inhibitors are classified as inactivators and reversible inhibitors based on the molecule-recognizing properties of the enzyme. In a minor role, transcription factors can also be downregulated by inhibitors. Currently, the active site copper iron-binding inhibitors such as kojic acid and chalcone exhibit tyrosinase inhibitory activity. Because the tyrosinase catalysis site structure is important for the mechanism determination of tyrosinase inhibitors, understanding the enzyme recognition and inhibitory mechanism of inhibitors is essential for the new development of tyrosinase inhibitors. The present review intends to classify current natural products identified by means of enzyme kinetics and copper chelation to exhibit tyrosinase enzyme inhibition. Full article