Cell Biochemistry and Biophysics最新文献

Na,K-ATPase is an electrogenic pump found in cell plasma membranes that acts as the basic unit of animal life. This enzyme is highly susceptible to cardiotonic steroid (CTS) inhibition. The role of Na,K-ATPase in signaling has introduced a novel viewpoint regarding the enzyme's function, as the ouabain-binding site is involved in several physiological processes. At high concentrations, ouabain blocks Na⁺ and K⁺ ion transport by Na,K-ATPase, whereas at low concentrations, it activates the signaling function of the enzyme. Notably, Na,K-ATPase does not fit into the categories of G protein-coupled receptors or ligand-gated ion channels. This indicates that it may be a distinct cell surface receptor that interacts with signaling molecules through allosteric regulation. In the present study, we have identified new modulators of Na,K-ATPase sensitivity to ouabain, and studied the kinetic effects of physiological concentrations of ouabain on Na,K-ATPase in the hippocampus. Specifically, Cytochrome c (Cytc) increases an affinity for ouabain and the maximal velocity (Vmax) of the enzyme. After binding to Na,K-ATPase, ouabain induces conformational changes that drive shifts between enzymatic cycles.

MicroRNAs (miRNAs) are noncoding RNAs that regulate the expression of target genes after transcription, and play important roles in the differentiation of hematopoietic stem cells. Many miRNAs are related to the occurrence of acute promyelocytic leukemia (APL) and play roles in the treatment response. Recently, we demonstrated that several miRNAs are differentially expressed in patients with relapsed and newly diagnosed APL; for example, miR-140-3p is significantly downregulated in patients with relapsed APL. In this study, via a dual luciferase assay, we verified that one of the direct target genes of miR-140-3p is hepatocyte growth factor (HGF). After different lentiviruses were transfected into NB4 cells, and flow cytometry and proliferation assays confirmed that low expression of miR-140-3p inhibited the differentiation and apoptosis of NB4 cells and induced proliferation by promoting cell cycle progression. In summary, our findings suggest that hepatocyte growth factor is a target gene of miR-140-3p. Moreover, upregulation of miR-140-3p expression in APL cells inhibits cell proliferation, arrests cell cycle progression, and promotes apoptosis and cell differentiation. Monitoring the levels of miR-140-3p and HGF may predict the risk of disease recurrence, and interfering with the miR-140-3p / HGF pathway may have therapeutic potential for treating recurrent APL.

Pattern recognition receptors (PRRs) help protect hosts from pathogens in different ways. They bind to pathogen-associated molecular patterns (PAMPs), damage-associated molecular patterns (DAMPs), or other homeostatic irregularities caused by these patterns to activate an immune response against a pathogen. Certain PRRs activate inflammasomes, leading to cell death and the formation of PANoptosomes, a key process in PANoptosis. PRRs help protect against pathogens, however an excessive number can cause harm to the body and even death. The mechanisms of how to control the PRRs remain unknown. Sundaram et al. [1] address this gap by investigating pathways that activate PANoptosomes in infection-mimicking conditions. They found that the sensor NLRP12 activated PANoptosomes causes inflammation in response to infections leading to the hypothesis that targeting the sensor NLRP12 could be a means to stop the harmful effects of excessive PRRs.This discovery suggests that targeting NLRP12 could mitigate the harmful effects of PRR overactivation, offering a potential therapeutic avenue.

To investigate the clinical efficacy of neonatal acute lung injury (NALI) and the mechanistic role of the DNA sensor Toll-like receptor 9 (TLR9) signaling pathway in treatment, Methods: This study enrolled 76 cases of NALI, randomly divided into 38 cases in the experimental group (intravenous injection of human immunoglobulin on the basis of nasal continuous positive airway pressure ventilation treatment) and 38 cases in the control group (nasal continuous positive airway pressure ventilation treatment). The pulmonary function parameters (forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and FEV1/FVC), TLR9 signaling pathway-related proteins and mRNA levels (TLR9, MyD88, p38), inflammatory factors (C-reactive protein (CRP), interleukin (IL)-1β, tumor necrosis factor (TNF)-α), and immune function indicators (immunoglobulin (Ig)A, IgG, IgM) were compared between the two groups. Pearson correlation analysis was conducted to examine the relationship between TLR9 signaling pathway protein expression and immune function indicators.After treatment, the pulmonary function parameters FVC, FEV1, and FEV1/FVC in neonates in the experimental group were considerably higher than those in the control group (P < 0.05). The serum levels of inflammatory factors CRP, IL-1β, and TNF-α in the experimental group of neonates following treatment were significantly lower than those in the control group (P < 0.05). After treatment, the levels of immune function indicators IgA, IgG, and IgM in neonates in the experimental group were considerably lower than those in the control group (P < 0.05). The protein expression levels of TLR9 showed a highly significant positive correlation with neonatal immune function indicators IgA, IgG, and IgM levels (P < 0.001). MyD88 protein expression exhibited a significant positive correlation with neonatal immune function indicators IgA, IgG, and IgM levels (P < 0.05). p38 protein expression demonstrated a significant positive correlation with neonatal immune function indicators IgA, IgG, and IgM levels (P < 0.05). In summary, the potential role of DNA receptor TLR9 signaling pathway-related proteins in the treatment of neonates with lung injury has been explored. The changes in the expression levels of TLR9/MyD88/p38 are associated with the production or regulation of immunoglobulins, and this association shows a certain correlation with the clinical efficacy in neonates with lung injury.

Aging is characterized by a decline in physiological functions and an increased susceptibility to age-related diseases. This study investigates the therapeutic potential of mesenchymal stem cells (MSCs) and pyrroloquinoline quinone (PQQ), individually and in combination, to counteract aging-related physiological declines, with a specific focus on their modulation of the AMP-activated protein kinase (AMPK) pathway, a key regulator of cellular energy homeostasis and stress response. Aging was induced in thirty-seven female rats using D-galactose, simulating the metabolic imbalances and oxidative stress characteristic of aging. The experimental groups included controls, aged rats without treatment, and aged rats treated with MSCs, PQQ, or a combined MSC-PQQ regimen. MSC homing analyses and Behavioral assessments, oxidative stress assays, gene expression profiling, histopathological evaluations were conducted to provide a multidimensional view of treatment efficacy. MSC homing confirmed successful tissue localization and repair, underscoring the regenerative capacity of MSCs. Remarkably, the combined MSC-PQQ therapy (APQQST) markedly improved anxiety-related behaviors, evidenced by increased rearing and grooming activities (p < 0.01). Oxidative stress biomarkers supported these findings; treated groups exhibited significantly reduced malondialdehyde (MDA) levels and elevated antioxidant defenses, including glutathione (GSH) and glutathione peroxidase (GPX) (p < 0.01). Gene expression analysis highlighted the beneficial upregulation of key genes such as LKB1, PFKFB3, TSC2, and HMGR, crucial for cellular energy homeostasis and stress response, with the combination therapy showing the most pronounced effects. Furthermore, histopathological assessments underscored significant liver tissue recovery in treated groups, particularly with combined treatment (APQQST), with minimal vacuolar degeneration and restored hepatic architecture (p < 0.01). These findings highlight the synergistic effects of MSCs and PQQ in mitigating behavioral, molecular, and physiological aspects of aging, underscoring their potential as promising therapeutic agents for promoting healthy aging and offering a foundation for future translational research and clinical applications.

Multiple myeloma (MM) is an incurable hematological malignancy with increasing prevalence. Prostate transmembrane androgen inducible protein 1 (PMEPA1) is positively associated with overall survival in MM patients, but the exact functions and mechanisms of PMEPA1 in MM have yet to be elucidated. PMEPA1 and neural precursor cell-expressed developmentally downregulated gene 4L (NEDD4L) levels in MM cells were examined. In RPMI-8226 cells with PMEPA1 overexpression or/and NEDD4L knockdown, cell proliferation, cycle distribution and apoptosis were evaluated with the application of CCK-8, EDU staining and flow cytometry. The BioGrid website and HDOCK SERVER were applied for predicting the binding between PMEPA1 and NEDD4L, which was checked by co-immunoprecipitation. Besides, the levels of proteins associated with proliferation (Ki67 and PCNA), apoptosis (Bcl-2, Bax and cleaved caspase3) and Wnt/β-catenin signaling (β-catenin, c-Myc and cyclin D1) was detected with immunoblotting. Finally, LiCl, an activator of Wnt/β-catenin pathway, was employed to treat RPMI-8226 cells to analyze the proliferation, cycle distribution and apoptosis of MM cells. As a result, PMEPA1 and NEDD4L were expressed at low levels in MM cells. PMEPA1 upregulation repressed proliferation induced cycle arrest and facilitated apoptosis of MM cells. Moreover, PMEPA1 bound to NEDD4L and upregulated NEDD4L expression in RPMI-8226 cells. Functionally, NEDD4L knockdown attenuated the influences of PMEPA1 overexpression on the proliferation, cycle distribution and apoptosis of RPMI-8226 cells. Additionally, PMEPA1 notably downregulated β-catenin, c-Myc and cyclin D1 expression in RPMI-8226 cells, which was abrogated by NEDD4L silencing. Further adding LiCl in RPMI-8226 cells led to the enhanced malignant biological behaviors. Collectively, PMEPA1 damaged MM progression through binding NEDD4L to inactivate Wnt/β-catenin signaling, which may be helpful to develop promising targets for MM treatment.

Hyperuricemia remains an elusive factor in the pathogenesis of vascular endothelial injury. This study elucidates the role of hydroxychloroquine (HCQ) in the context of uric acid (UA)-induced vascular endothelial cell damage. Human umbilical vein endothelial cells (HUVECs) were exposed to varying UA concentrations (6 mg/dL to 50 mg/dL) for 48 h, or to 50 mg/dL UA for different time points (6 to 72 h). We observed a concentration- and time-dependent inhibition of cell proliferation, particularly at 40 mg/dL and 50 mg/dL UA. The autophagy marker LC3 exhibited reduced fluorescence intensity post-UA treatment, along with decreased expression of LC3-II/LC3I, beclin1, and p62, indicating impaired autophagy. The mechanistic exploration revealed that HCQ, in conjunction with the mitochondrial autophagy inhibitor Cyclosporine A (CsA), exacerbated the inhibitory effects of UA on HUVEC autophagy. This was evidenced by a further reduction in mitochondrial autophagy-related proteins and diminished fluorescence of LC3-II/LC3-I and Parkin, culminating in suppressed cell proliferation and accelerated cell senescence and apoptosis. Conversely, the co-treatment with the mitochondrial autophagy inducer carbonyl cyanide m-chlorophenyl hydrazine (CCCP) and HCQ mitigated the detrimental effects of UA on HUVEC autophagy. This intervention led to increased expression of PINK1, Parkin, Bnip3, and Nix, along with enhanced fluorescence of LC3-II/LC3-I and Parkin, effectively inhibiting cell senescence and apoptosis while promoting cell proliferation. In conclusion, our findings underscore the pivotal role of HCQ in modulating UA-mediated vascular endothelial cell damage through the inhibition of mitophagy, providing novel insights into the therapeutic potential of targeting HCQ in the management of hyperuricemia-associated vascular complications.

Sulfanilic acid (SFA) crystal is well known as an effective material for photonic, electro-optical, harmonic generating and biomedical applications. A well-known nonlinear optical material, a high-quality SFA single crystal made utilizing the slow evaporation solution method (SEST) is the subject of this article. A 75 days development period yielded a transparent SFA single crystal measuring 5 × 5 × 2 mm³. The grown crystal used for different characterizations like Single crystal XRD used to find out the cell parameters. Fourier transforms infrared utilized to identify the band assignments. UV-Visible analysis used to detect the absorbance of the crystal and it is utilized for optical application. Photoluminescence studies utilized to recognize the excitation and emission of the grown crystal. Fluorescence used for determining the crystallinity and purity of the sample. The quantitative analysis is verified by using Elemental Dispersive Analysis by X-Rays. Scanning Electron Microscopy utilized to identify the structural and morphological characteristics. To the best of our knowledge, this paper is the first to provide the generated crystal that was used to analyze cytotoxicity and larvacidal activity. Assessment of larvicidal activity was used to ascertain the anti-malarial efficacy. We tested the items on MCF7-Human Breast cancer cell line and MCF7 Vero cells using the MTT Assay to identify the molecular basis of their cytotoxicity in vitro. Biological and optical are two areas that could benefit from the created crystal.

Differential expression patterns of growth factor (EGFR, HER-2) and hormonal (ER, PR) receptors in breast cancer (BC) remain crucial for evaluating and tailoring therapeutic interventions. This study investigates differential expression profiles of hormonal and growth factor receptors in BC patients and across age groups, major subclasses, disease stages and tumor histology and survival rates, the efficacy of emerging clinical trial drugs (Dabrafenib and Palbociclib) and elucidating their molecular interaction mechanisms for efficient therapeutic strategies. Gene and protein expression analysis in the normal vs BC and across age groups and major subclasses reveals divergent patterns as EGFR and HER-2 levels are reduced in tumors versus normal tissue, while ER and PR levels are higher, particularly in luminal subtypes. However, there was no significant difference in survival rates among high and low/medium expression levels of EGFR and PR receptors. Conversely, patients with high HER-2 and ER expression exhibited poorer survival rates compared to low or medium expression levels. The in vitro findings indicate that Dabrafenib exhibits greater effectiveness than Palbociclib in suppressing various BC cells such as MCF-7 (Luminal), MDA-MB-231 (Triple-Negative), SKBR-3 (HER-2 + ) proliferation, promoting cell death, (IC₅₀ of Dab < Pal) at 24 and 48 h, ROS production, and reduced ER and PR, elevated HER-2 with no change in EGFR expression. Molecular simulation studies revealed Dabrafenib's thermodynamically stable interactions (ΔG), tighter binding, and less structural deviation in the order EGFR > HER-2 > ER > PR as compared to Palbociclib (HER-2 > ER > PR = EGFR). These results indicate that Dabrafenib, compared to Palbociclib, more effectively regulates breast cancer cell proliferation through specific interactions with hormonal and growth factor receptors towards a repurposing approach.