Search Results (5,740)

Spinal cord injury (SCI) results in a cascade of primary and secondary damage, with apoptosis being a prominent cause of neuronal cell death. The X-linked inhibitor of apoptosis (XIAP) plays a critical role in inhibiting apoptosis, but its expression is reduced following SCI, contributing to increased neuronal vulnerability. This study investigates the regulatory role of miR-199a-5p on XIAP expression in the context of SCI. Using bioinformatic tools, luciferase reporter assays, and in vitro and in vivo models of SCI, we identified miR-199a-5p as a post-transcriptional regulator of XIAP. Overexpression of miR-199a-5p significantly reduced XIAP protein levels, although no changes were observed at the mRNA level, suggesting translational repression. In vivo, miR-199a-5p expression was upregulated at 3 and 7 days post-injury, while XIAP expression inversely decreased in both neurons and oligodendrocytes, being particularly significant in the latter at 7 dpi. These findings suggest that miR-199a-5p contributes to the downregulation of XIAP and may exacerbate neuronal apoptosis after SCI. Targeting miR-199a-5p could offer a potential therapeutic strategy to modulate XIAP levels and reduce apoptotic cell death in SCI. Full article

ECM stiffness significantly influences the differentiation of adipose-derived stem cells (ADSCs), with YAP—a key transcription factor in the Hippo signaling pathway—playing a pivotal role. This study investigates the effects of ECM stiffness on ADSC differentiation and its relationship with YAP signaling. Various hydrogel concentrations were employed to simulate different levels of ECM stiffness, and their impact on ADSC differentiation was assessed through material properties, adipocyte-specific gene expression, lipid droplet staining, YAP localization, and protein levels. Our results demonstrated that increasing hydrogel stiffness enhanced adipocyte differentiation in a gradient manner. Notably, inhibiting YAP signaling further increased lipid droplet accumulation, suggesting that ECM stiffness influences adipogenesis by modulating YAP signaling and its cytoplasmic phosphorylation. This study elucidates the molecular mechanisms underlying ECM stiffness-dependent lipid deposition, highlighting YAP’s regulatory role in adipogenesis. These findings provide valuable insights into the regulation of cell differentiation and have important implications for tissue engineering and obesity treatment strategies. Full article

Watercress (Nasturtium officinale R.Br.) is a cruciferous aquatic vegetable that possesses significant nutritional value. The NAC family is a transcription factor family specific to plants that play an important role in regulating plant responses to abiotic stress. In order to investigate the response of NAC genes to flooding stress in watercress, we conducted a study on the NoNAC family. In this study, a total of 119 NoNAC genes were obtained through genome-wide identification. Phylogenetic analysis indicated that the NoNAC family members can be categorized into ten subgroups. The results of gene structure analysis revealed that each branch within the subgroups exhibited similar motif composition and gene structure. The heatmap analysis showed that several NoNAC genes demonstrated tissue-specific expression patterns, suggesting their potential as regulators of associated tissue development. As an aquatic plant, watercress serves as a valuable material for investigating plant resistance to flooding stress. This study found that flooding can significantly increase the watercress plant height, which is a typical escape strategy under flooding. The analysis of the expression of NoNAC genes in the stem transcriptome after flooding indicated that only NoNAC36a consistently exhibited significant differential changes and down-regulated expression at the three time points of flooding treatment. This suggests that NoNAC36a may be involved in regulating watercress plant height increases under flooding stress. The utilization of a virus-induced gene silencing assay to investigate the biological function of NoNAC36a revealed that NoNAC36a silencing caused cell elongation and expansion, thus increasing watercress plant height. The yeast one-hybrid and dual luciferase assays demonstrated that NoNAC36a binds the promoter of NoXTH33 and inhibits its expression. Subsequently, the results of yeast two-hybrid, luciferase complementary, and pull-down assays revealed the interaction between NoMOB1A and NoNAC36a in vivo and in vitro. Sequence alignment indicated that NoMOB1A and AtMOB1A share an identical amino acid sequence. RT-qPCR analysis indicated that flooding prompted the expression of NoMOB1A in stems. Thus, it is speculated that NoMOB1A may exhibit functions similar to AtMOB1A and that the up-regulation of NoMOB1A expression in stems may facilitate an increase in plant height under flooding. In summary, the NoNAC family was analyzed, and revealed a regulatory network centered on NoNAC36a that facilitates watercress resistance to flooding stress. This study enhanced the understanding of the NoNAC genes and established a theoretical foundation for investigating plant flooding tolerance. Full article

Background and Objectives: A novel antitubercular cyclic peptide, Cyclo(1,6)-Ac-CLYHFC-NH₂, was designed to bind at the rifampicin (RIF) binding site on the RNA polymerase (RNAP) of Mycobacterium tuberculosis (MTB). This peptide inhibits RNA elongation in the MTB transcription initiation assay in the nanomolar range, which can halt the MTB transcription initiation complex, similar to RIF. Therefore, determining the solution conformation of this peptide is useful in improving the peptide’s binding affinity to the RNAP. Methods: Here, the solution structure of Cyclo(1,6)-Ac-CLYHFC-NH₂ was determined by two-dimensional (2D) NMR experiments and NMR-restrained molecular dynamic (MD) simulations. Results: All protons of Cyclo(1,6)-Ac-CLYHFC-NH₂ were assigned using TOCSY and NOE NMR spectroscopy. The NOE cross-peak intensities were used to calculate interproton distances within the peptide. The J_NH-HCα coupling constants were used to determine the possible Phi angles within the peptide. The interproton distances and calculated Phi angles from NMR were used in NMR-restrained MD simulations. The NOE spectra showed NH-to-NH cross-peaks at Leu2-to-Tyr3 and Tyr3-to-His4, indicating a βI-turn formation at the Cys1-Leu2-Tyr3-His4 sequence. Conclusions: The NMR-restrained MD simulations showed several low-energy conformations that were congruent with the NMR data. Finally, the conformation of this peptide will be used to design derivatives that can better inhibit RNAP activity. Full article

Androstenedione (AD) is an important intermediate for the production of steroidal drugs. The process of transforming phytosterols into AD by Mycolicibacterium is mainly the degradation process of the phytosterol side chain, and the excessive accumulation of propionyl-CoA produced by Mycobacterium will produce toxic effects, which seriously restricts the transformation performance of strains. In this study, Mycolicibacterium sp. LZ2 (Msp) was used as the research object to study the transcription factor PccD of the TetR family, which has the role of propionyl-CoA metabolism regulation. By constructing overexpression and deletion strains of pccD, it was confirmed that pccD had an inhibitory effect on the transcription of propionyl-CoA carboxylase genes (pccA and pccB). Electrophoretic Mobility Shift Assay (EMSA) and DNase I footprint analysis demonstrated that PccD is directly involved in the transcriptional regulation of pccA and pccB and is a negative transcriptional regulator of the pcc operon. In the study of phytosterol transformation, the growth rate and bacterial viability of Msp-ΔpccD were higher than Msp, but the growth of Msp-pccD was inhibited. As a result of testing of intracellular propionyl-CoA levels and AD production yields, it was found that lower propionyl-CoA levels and higher AD production yields were observed in Msp-ΔpccD. The results expand the cognition of propionyl-CoA metabolism regulation and provide a theoretical basis and reference for the rational transformation of phytosterol transformation strains and secondary metabolite synthesis strains with propionyl-CoA as a substrate, which has important research significance. Full article

Fibromyalgia is a chronic illness usually accompanied by long-lasting, general pain throughout the body, often accompanied by anxiety, depression, fatigue, and sleep disruption. Meanwhile, doctors and scientists have not entirely discovered detailed mechanisms; patients always have an exaggerated sensation to pervasive pain without satisfied medical service. Given the lack of knowledge on its underlying mechanism, current treatments aim to provide pain and/or symptom relief. The present study aimed to clarify the role of cannabinoid receptor 1 (CB1) signaling in a mouse fibromyalgia pain model. To develop the mouse fibromyalgia model, mice were subjected to intermittent cold stress (ICS). Our results indicated that mechanical (2.09 ± 0.09 g) and thermal hyperalgesia (4.77 ± 0.29 s), which were evaluated by von Frey and Hargraves’ tests, were induced by ICS, suggesting successful modeling. The hurting replies were then provoked by electroacupuncture (EA) but not for sham EA mice. Further, in a Western blot analysis, we found significantly decreased CB1 protein levels in the thalamus, somatosensory cortex, and anterior cingulate cortex. In addition, the levels of pain-related protein kinases and transcription factor were increased. Treatment with EA reliably increased CB1 expression in various brain regions sequentially alleviated by nociceptive mediators. Furthermore, the administration of a CB1 agonist significantly attenuated fibromyalgia pain, reversed EA analgesia by the CB1 antagonist, and further reversed the chemogenetic inhibition of SSC. Our innovative findings evidence the role of CB1 signaling in the interaction of EA and fibromyalgia, suggesting its potential for clinical trials and as a treatment target. Full article

(1) T-2 toxin synthesized by Fusarium oxysporum (F. oxysporum) can cause deterioration of dried fish and endanger human health. (2) The molecular mechanism by which antibacterial lipopeptides surfactin inhibited F. oxysporum growth and toxin production was elucidated by investigating the intracellular ROS production pathway and the subcellular distribution and transcriptional activity of the transcription factor Yap1 and its regulation of Tri5 gene in F. oxysporum. (3) Surfactin caused hyphal damage and nucleic acid and protein leakage; thus, the growth of F. oxysporum was disrupted. Surfactin’s excessive accumulation of intracellular ROS triggered the translocation of transcription factor Yap1 into the nucleus, resulting in toxin cluster gene Tri5 expression inhibition, thereby blocking T-2 toxin synthesis. (4) This is a novel mechanism by which surfactin inhibits the growth and T-2 toxin synthesis of F. oxysporum from multiple aspects, including cell structural integrity and the ROS-Yap1 signaling pathway. (5) This study provides a theoretical basis for the application of surfactin in the antifungal control of aquatic dry products. Full article

Lupus nephritis (LN) is a severe form of systemic lupus erythematosus (SLE), characterized by inflammation in the renal glomeruli and tubules. Previous research has demonstrated that dihydroartemisinin (DHA) can reduce inflammatory damage in LN mouse models. Oxymatrine, which has similar biological properties to DHA, may also provide therapeutic benefits. This study aims to investigate the effects of oxymatrine on LN using a murine model and examines its molecular mechanisms through an analysis of microarray datasets from LN patients. The analysis identified differentially expressed genes (DEGs) in renal tissues, regulated by the transcription factor Yin Yang 1 (YY1), which was found to be significantly upregulated in LN patient kidneys. The results indicate that oxymatrine targets the YY1/IL-6/STAT3 signaling pathway. In cell models simulating renal inflammation, oxymatrine reduced YY1 expression and inhibited the secretion of inflammatory factors (IFs), thereby diminishing inflammation. YY1 is crucial in modulating IFs’ secretion and contributing to LN pathogenesis. Additionally, oxymatrine’s interaction with YY1, leading to its downregulation, appears to be a key mechanism in alleviating LN symptoms. These findings support oxymatrine as a promising therapeutic agent for LN, offering new avenues for treating this autoimmune kidney disorder. Full article

Up to 40% of patients with diabetes mellitus will develop diabetic kidney disease (DKD), characterized pathologically by the accumulation of extracellular matrix proteins, which leads to the loss of kidney function over time. Our previous studies showed that the pan-protease inhibitor alpha 2-macroglobulin (A2M) is increased in DKD and is a critical regulator of the fibrotic response in glomerular mesangial cells (MC), an initial site of injury during DKD development. How A2M is regulated by high glucose (HG) has not yet been elucidated and is the focus of this investigation. Using serial deletions of the full A2M promoter, we identified the −405 bp region as HG-responsive in MC. Site-directed mutagenesis, siRNA, and ChIP studies showed that the transcription factor, nuclear factor of activated T cells 5 (NFAT5), regulated A2M promoter activity and protein expression in response to HG. Forkhead box P1 (FOXP1) served as a cooperative binding partner for NFAT5, required for A2M upregulation. Lastly, we showed that Smad3, known for its role in kidney fibrosis, regulated A2M promoter activity and protein production independently of HG. The importance of NFAT5, FOXP1, and Smad3 in A2M regulation was confirmed in ex vivo studies using isolated glomeruli. In conclusion, Smad3 is required for basal and HG-induced A2M expression, while NFAT5 and FOXP1 cooperatively regulate increased A2M transcription in response to HG. Inhibition of NFAT5/FOXP1 will be further evaluated as a potential therapeutic strategy to inhibit A2M production and attenuate profibrotic signaling in DKD. Full article

Background: Schwann cells (SCs) and their plasticity contribute to the peripheral nervous system’s capacity for nerve regeneration after injury. The Egr2/Krox20 promoter antisense RNA (Egr2-AS) recruits chromatin remodeling complexes to inhibit Egr2 transcription following peripheral nerve injury. Methods: RNA-seq and ATAC-seq were performed on control cells, Lenti-GFP-transduced cells, and cells overexpressing Egr2-AS (Lenti-AS). Egr2 AS-RNA was cloned into the pLVX-DsRed-Express2-N1 lentiviral expression vector (Clontech, Mountain View, CA, USA), and the levels of AS-RNA expression were determined. Ezh2 and Wdr5 were immunoprecipitated from rat SCs and RT-qPCR was performed against AS-Egr2 RNA. ChIP followed by DNA purification columns was used to perform qPCR for relevant promoters. Hi-C, HiC-DC+, R, Bioconductor, and TOBIAS were used for significant and differential loop analysis, identifications of COREs and CORE-promotor loops, comparisons of TF activity at promoter sites, and identification of site-specific TF footprints. OnTAD was used to detect TADs, and Juicer was used to identify A/B compartments. Results: Here we show that a Neuregulin-ErbB2/3 signaling axis mediates binding of the Egr2-AS to YY1^Ser184 and regulates its expression. Egr2-AS modulates the chromatin accessibility of Schwann cells and interacts with two distinct histone modification complexes. It binds to EZH2 and WDR5 and enables targeting of H3K27me3 and H3K4me3 to promoters of Egr2 and C-JUN, respectively. Expression of the Egr2-AS results in reorganization of the global chromatin landscape and quantitative changes in the loop formation and contact frequency at domain boundaries exhibiting enrichment for AP-1 genes. In addition, the Egr2-AS induces changes in the hierarchical TADs and increases transcription factor binding scores on an inter-TAD loop between a super-enhancer regulatory hub and the promoter of mTOR. Conclusions: Our results show that Neuregulin-ErbB2/3-YY1 regulates the expression of Egr2-AS, which mediates remodeling of the chromatin landscape in Schwann cells. Full article

Background: Small-cell lung cancer (SCLC) has a poor prognosis because it is often diagnosed after it has spread and develops multi-drug resistance. Epibrassinolide (EB) is a plant steroid hormone with widespread distribution and physiological effects. In plants, EB-activated gene expression occurs via a GSK-mediated signaling pathway, similar to Wnt-β-catenin signaling in animal cells that is elevated in cancer cells. Methods: This mechanistic parallel prompted investigations of the molecular interactions of EB on drug-sensitive (H69) and multi-drug-resistant (VPA) SCLC cells. Cellular and molecular investigations were performed. Results: Pharmacologic interactions between EB and the Wnt signaling inhibitors IGC-011 and PRI-724 were determined by the combination index method and showed antagonism, indicating that EB acts on the same pathway as these inhibitors. Following incubation of drug-sensitive and drug-resistant SCLC cells with EB, there was a reduction in β-catenin (e.g., 3.8 to 0.7 pg/µg protein), accompanied by a reduction in β-catenin promoter activity, measured by firefly luciferase-coupled promoter element transfection. Cellular β-catenin concentration is regulated by the active form of GSK3β. In Wnt signaling, active GSK3β is converted to inactive pGSK3β, thereby increasing the concentration of β-catenin. After incubation of SCLC cells with EB, there was a reduction in the inactive form (pGSK3β) and a relative increase in the active form (GSK3β). In vitro enzyme assays showed that EB did not inhibit purified GSK3β, but there was non-competitive inhibition when SCLC cell extracts were used as the source of enzyme. This indirect inhibition by EB indicates that it may act on the Wnt pathway by blocking the phosphorylation of GSK3β. The protein levels of three SCLC tumor markers, namely, NSE, CAV1, and MYCL1, were elevated in drug-resistant SCLC cells. EB incubation led to a significant reduction in the levels of the three markers. Two major effects of EB on SCLC cells are the promotion of apoptosis and the reversal of drug resistance. Transcriptional analyses showed that after exposure of SCLC cells to EB, there were increases in the expression of genes encoding apoptotic inducers (e.g., BAX and FAS) and effectors (e.g., CASP3) and reductions in the expression of genes encoding apoptosis inhibitors (e.g., survivin). PGP1 and MRP1, two membrane efflux pumps expressed in SCLC cells, were elevated in drug-resistant cells, but EB incubation did not affect these protein levels. Cellular assays of drug efflux by PGP1 showed an increase in drug-resistant cells, but EB did not alter efflux activity. Following exposure to human liver microsomes, EB was metabolized by NADPH-dependent oxidation and UDPG-dependent glucuronidation, as evidenced by the elimination of EB cytotoxicity against SCLC cells. Conclusions: Taken together, these data indicate that EB, a steroid hormone in plants consumed in the human diet, is pharmacologically active in drug-sensitive and drug-resistant SCLC cells in the Wnt signaling pathway, alters apoptotic gene expression, and is a substrate for microsomal modifications. Full article

Obesity is a chronic and complex disease defined by the excessive deposition of fat and is highly associated with oxidative stress. Adzuki bean saponins (ABS) showed anti-obesity activity in our previous in vivo study; however, the active saponins of adzuki beans and potential mechanisms are still unclear. This research aims to elucidate the anti-obesity effects of ABS in improving lipid metabolism and oxidative stress, exploring the effective ingredients and potential molecular mechanisms through UHPLC-QE-MS analysis, network pharmacology, bioinformatics, and in vitro experiments both in the 3T3-L1 cell line and HepG2 cell line. The results indicate that ABS can improve intracellular lipid accumulation, adipogenesis, oxidative stress, and mitochondrial damage caused by lipid accumulation including ROS generation, abnormal mitochondrial membrane potential, and ATP disorder. Fifteen saponin components were identified with the UHPLC-QE-MS analysis. The network pharmacology and bioinformatics analyses indicated that the PI3K/Akt signaling pathway is associated with the bioactive effect of ABS. Through Western blotting and immunofluorescence analysis, the anti-obesity effect of ABS is achieved through regulation of the PI3K/Akt/GSK3β/β-catenin signaling pathway and activation of downstream transcription factor c-Myc in the lipid accumulation cell model, and regulation of β-catenin signaling and inhibition of downstream transcription factor C/EBPα in the adipocyte cell model. These results illustrate the biological activity of ABS in improving fat metabolism and oxidative stress by restoring mitochondrial function through β-catenin signaling, the PI3K/Akt/GSK3β/β-catenin signaling pathway, laying the foundation for its further development. Full article

The major pathological characteristics of Alzheimer’s disease (AD) include senile plaques and neurofibrillary tangles (NFTs), which are mainly composed of aggregated amyloid-beta (Aβ) peptide and hyperphosphorylated tau protein, respectively. The excessive production of reactive oxygen species (ROS) and neuroinflammation are crucial contributing factors to the pathological mechanisms of AD. Hypoxia-inducible factor-1 (HIF-1) is a transcription factor critical for tissue adaption to low-oxygen tension. Growing evidence has suggested HIF-1 as a potential therapeutic target for AD; conversely, other experimental findings indicate that HIF-1 induction contributes to AD pathogenesis. These previous findings thus point to the complex, even contradictory, roles of HIF-1 in AD. In this review, we first introduce the general pathogenic mechanisms of AD as well as the potential pathophysiological roles of HIF-1 in cancer, immunity, and oxidative stress. Based on current experimental evidence in the literature, we then discuss the possible beneficial as well as detrimental mechanisms of HIF-1 in AD; these sections also include the summaries of multiple chemical reagents and proteins that have been shown to exert beneficial effects in AD via either the induction or inhibition of HIF-1. Full article

Fowl adenovirus serotype 4 (FAdV-4) outbreaks have caused significant economic losses in the Chinese poultry industry since 2015. The relationships among viral structural proteins in infected hosts are relatively unknown. To explore the role of different parts of the fiber-1 protein in FAdV-4-infected hosts, we truncated fiber-1 into fiber-1-Δ1 (73–205 aa) and fiber-1-Δ2 (211–412 aa), constructed pEF1α-HA-fiber-1-Δ1 and pEF1α-HA-fiber-1-Δ2 and then transfected them into leghorn male hepatocyte (LMH) cells. After FAdV-4 infection, the roles of fiber-1-Δ1 and fiber-1-Δ2 in the replication of FAdV-4 were investigated, and transcriptome sequencing was performed. The results showed that the fiber-1-Δ1 and fiber-1-Δ2 proteins were the shaft and knob domains, respectively, of fiber-1, with molecular weights of 21.4 kDa and 29.6 kDa, respectively. The fiber-1-Δ1 and fiber-1-Δ2 proteins were mainly localized in the cytoplasm of LMH cells. Fiber-1-Δ2 has a greater ability to inhibit FAdV-4 replication than fiber-1-Δ1, and 933 differentially expressed genes (DEGs) were detected between the fiber-1-Δ1 and fiber-1-Δ2 groups. Functional analysis revealed these DEGs in a variety of biological functions and pathways, such as the phosphoinositide 3-kinase–protein kinase b (PI3K–Akt) signaling pathway, the mitogen-activated protein kinase (MAPK) signaling pathway, cytokine–cytokine receptor interactions, Toll-like receptors (TLRs), the Janus tyrosine kinase–signal transducer and activator of transcription (Jak–STAT) signaling pathway, the nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) signaling pathway, and other innate immune pathways. The mRNA expression levels of type I interferons (IFN-α and INF-β) and proinflammatory cytokines (IL-1β, IL-6 and IL-8) were significantly increased in cells overexpressing the fiber-1-Δ2 protein. These results demonstrate the role of the knob domain of the fiber-1 (fiber-1-Δ2) protein in FAdV-4 infection and provide a theoretical basis for analyzing the function of the fiber-1 protein of FAdV-4. Full article

The hedgehog (Hh) signalling pathway plays a key role in both embryonic and postnatal development of the intestine and is responsible for gut homeostasis. It regulates stem cell renewal, formation of the villous–crypt axis, differentiation of goblet and Paneth cells, the cell cycle, apoptosis, development of gut innervation, and lipid metabolism. Ligands of the Hh pathway, i.e., Indian hedgehog (Ihh) and Sonic hedgehog (Shh), are expressed by superficial enterocytes but act in the mesenchyme, where they are bound by a Patched receptor localised on myofibroblasts and smooth muscle cells. This activates a cascade leading to the transcription of target genes, including those encoding G1/S-specific cyclin-D2 and -E1, B-cell lymphoma 2, fibroblast growth factor 4, and bone morphogenetic protein 4. The Hh pathway is tightly connected to Wnt signalling. Ihh is the major ligand in the Hh pathway. Its activation inhibits proliferation, while its blocking induces hyperproliferation and triggers a wound-healing response. Thus, Ihh is a negative feedback regulator of cell proliferation. There are data indicating that diet composition may affect the expression of the Hh pathway genes and proteins, which in turn, induces changes in mucosal architecture. This was shown for fat, vitamin A, haem, berberine, and ovotransferrin. The Hh signalling is also affected by the intestinal microbiota, which affects the intestinal barrier integrity. This review highlights the critical importance of the Hh pathway in shaping the intestinal mucosa and summarises the results obtained so far in research on the effect of dietary constituents on the activity of this pathway. Full article