Cell Model Research Articles

NADPH Oxidase 5 (NOX5) Upregulates MMP-10 Production and Cell Migration in Human Endothelial Cells.

NADPH oxidases (NOXs) have been described as critical players in vascular remodeling, a mechanism modulated by matrix metalloproteinases. In this study, we describe for the first time the upregulation of MMP-10 through the activation of NOX5 in endothelial cells. In a chronic NOX5 overexpression model in human endothelial cells, MMP-10 production was measured at different levels: extracellular secretion, gene expression (mRNA and protein levels), and promoter activity. Effects on cell migration were quantified using wound healing assays. NOX5 overexpression increased MMP-10 production, favoring cell migration. In fact, NOX5 and MMP-10 silencing prevented this promigratory effect. We showed that NOX5-mediated MMP-10 upregulation involves the redox-sensitive JNK/AP-1 signaling pathway. All these NOX5-dependent effects were enhanced by angiotensin II (Ang II). Interestingly, MMP-10 protein levels were found to be increased in the hearts of NOX5-expressing mice. In conclusion, we described that NOX5-generated ROS may modulate the MMP-10 expression in endothelial cells, which leads to endothelial cell migration and may play a key role in vascular remodeling.

Enhanced anti-tumor efficacy of electroporation (EP)-mediated DNA vaccine boosted by allogeneic lymphocytes in pre-established tumor models

BackgroundTumor-reactive T cells play a crucial role in anti-tumor responses, but T cells induced by DNA vaccination are time-consuming processes and exhibit limited anti-tumor efficacy. Therefore, we evaluated the anti-tumor effectiveness of reactive T cells elicited by electroporation (EP)-mediated DNA vaccine targeting epidermal growth factor receptor variant III (pEGFRvIII plasmid), in conjunction with adoptive cell therapy (ACT), involving the transfer of lymphocytes from a pEGFRvIII EP-vaccinated healthy donor.MethodsThe validation of the established pEGFRvIII plasmid and EGFRvIII-positive cell model was confirmed through immunofluorescence and western blot analysis. Flow cytometry and cytotoxicity assays were performed to evaluate the functionality of antigen-specific reactive T cells induced by EP-mediated pEGFRvIII vaccines, ACT, or their combination. The anti-tumor effectiveness of EP-mediated pEGFRvIII vaccines alone or combined with ACT was evaluated in the B16F10-EGFRvIII tumor model.ResultsEP-mediated pEGFRvIII vaccines elicited serum antibodies and a robust cellular immune response in both healthy and tumor-bearing mice. However, this response only marginally inhibited early-stage tumor growth in established tumor models. EP-mediated pEGFRvIII vaccination followed by adoptive transfer of lymphocytes from vaccinated healthy donors led to notable anti-tumor efficacy, attributed to the synergistic action of antigen-specific CD4+ Th1 cells supplemented by ACT and antigen-specific CD8+ T cells elicited by the EP-mediated DNA vaccination.ConclusionsOur preclinical studies results demonstrate an enhanced anti-tumor efficacy of EP-mediated DNA vaccination boosted with adoptively transferred, vaccinated healthy donor-derived allogeneic lymphocytes.

C5a Induces Inflammatory Signaling and Apoptosis in PC12 Cells through C5aR-Dependent Signaling: A Potential Mechanism for Adrenal Damage in Sepsis.

The complement system is critically involved in the pathogenesis of sepsis. In particular, complement anaphylatoxin C5a is generated in excess during sepsis, leading to cellular dysfunction. Recent studies have shown that excessive C5a impairs adrenomedullary catecholamine production release and induces apoptosis in adrenomedullary cells. Currently, the mechanisms by which C5a impacts adrenal cell function are poorly understood. The PC12 cell model was used to examine the cellular effects following treatment with recombinant rat C5a. The levels of caspase activation and cell death, protein kinase signaling pathway activation, and changes in inflammatory protein expression were examined following treatment with C5a. There was an increase in apoptosis of PC12 cells following treatment with high-dose C5a. Ten inflammatory proteins, primarily involved in apoptosis, cell survival, and cell proliferation, were upregulated following treatment with high-dose C5a. Five inflammatory proteins, involved primarily in chemotaxis and anti-inflammatory functions, were downregulated. The ERK/MAPK, p38/MAPK, JNK/MAPK, and AKT protein kinase signaling pathways were upregulated in a C5aR-dependent manner. These results demonstrate an apoptotic effect and cellular signaling effect of high-dose C5a. Taken together, the overall data suggest that high levels of C5a may play a role in C5aR-dependent apoptosis of adrenal medullary cells in sepsis.

Luteolin alleviates airway remodeling in asthma by inhibiting the epithelial-mesenchymal transition via β-catenin regulation

BackgroundAsthma is a prevalent long-term inflammatory condition that causes airway inflammation and remodeling. Increasing evidence indicates that epithelial-mesenchymal transition (EMT) holds a prominent implication in airway reconstruction in patients with asthma. Flavonoids obtained from Chinese Materia Medica (CMM), such as Luteolin (Lut), exhibit various beneficial effects in various asthma models. Lut has been shown to mitigate various asthma symptoms, including airway inflammation, hyperresponsiveness, bronchoconstriction, excessive mucus production, pulmonary autophagy, and neutrophilic asthma. However, whether flavonoids can suppress EMT-associated airway remodeling in asthma and the fundamental mechanisms involved remain unclear, with no studies specifically addressing Lut in this context. PurposeTo evaluate the inhibition of airway remodeling in asthma by Lut and its potential mechanisms, while examining the significance of β-catenin in this process through cellular and animal studies. MethodsA BEAS-2B cell model stimulated by lipopolysaccharide (LPS) was established in vitro. Wound closure and Transwell assays were utilized to assess the cellular migratory ability. EMT- and fibrosis-related markers in LPS-stimulated cells were evaluated using RT-qPCR and western blotting. The status of the β-catenin/E-cadherin and β-catenin destruction complexes was evaluated using western blotting, immunofluorescence (IF) staining, and co-immunoprecipitation (Co-IP) analysis. The regulatory function of Lut in β-catenin-dependent EMT was further validated by β-catenin overexpression with adenovirus transduction and siRNA-mediated knockdown of β-catenin. Moreover, the counts of different types of bronchoalveolar lavage fluid (BALF) inflammatory cells from mice with asthma induced by ovalbumin (OVA) were evaluated in vivo using Congo red staining. Hematoxylin and eosin (H&E), Masson's trichrome, and periodic acid-Schiff (PAS) staining were used to evaluate collagen deposition, mucus production, and inflammation in murine lung tissues. Western blotting and immunohistochemistry (IHC) assays were used to assess EMT- and fibrosis-related markers in the lung tissues in vivo. ResultSix naturally derived flavonoids, including Lut, attenuated cell migration and prevented EMT in LPS-treated BEAS-2B cells. Moreover, Lut suppressed TGF-β1, MMP-9, fibronectin (FN), and α-smooth muscle actin (α-SMA) levels in LPS-stimulated BEAS-2B cells. Additionally, Lut downregulated the levels of β-catenin by modulating the β-catenin/E-cadherin and β-catenin destruction complexes, highlighting the pivotal role of β-catenin in EMT inhibition by Lut in LPS-stimulated BEAS-2B cells. Furthermore, Lut suppressed airway inflammation and attenuated EMT-associated airway remodeling through β-catenin blockade in OVA-induced asthmatic mice. The bronchial wall thickness notably reduced from 37.24 ± 4.00 μm in the asthmatic model group to 30.06 ± 4.40 μm in the Lut low-dose group and 24.69 ± 2.87 μm in the Lut high-dose group. ConclusionAccording to our current understanding, this research is the first to reveal that Lut diminishes airway remodeling in asthma by inhibiting EMT via β-catenin regulation, thereby filling a research gap concerning Lut and flavonoids. These results provide a theoretical basis for treating asthma with anti-asthmatic CMM, as well as a candidate and complementary therapeutic approach to treat asthma.

Loss of EMI1 compromises chromosome stability and is associated with cellular transformation in colonic epithelial cell contexts.

Colorectal cancer (CRC) is still a leading cause of cancer deaths worldwide. Thus, identifying the aberrant genes and proteins underlying disease pathogenesis is critical to improve early detection methods and develop novel therapeutic strategies. Chromosome instability (CIN), or ongoing changes in chromosome complements, is a predominant form of genome instability. It is a driver of genetic heterogeneity found in ~85% of CRCs. Although CIN contributes to CRC pathogenesis, the molecular determinants underlying CIN remain poorly understood. Recently, EMI1, an F-box protein, was identified as a candidate CIN gene. In this study, we sought to determine the impact reduced EMI1 expression has on CIN and cellular transformation. Coupling siRNA-based silencing and CRISPR/Cas9 knockout clones with quantitative imaging microscopy we evaluated the impact reduced EMI1 expression has on CIN and cellular transformation in four colonic epithelial cell contexts. Quantitative imaging microscopy data revealed that reduced EMI1 expression induces increases in CIN phenotypes in both transient (siRNA) and constitutive (CRISPR/Cas9) cell models that are associated with increases in DNA damage and cellular transformation phenotypes in long-term studies. This study determined that reduced EMI1 expression induces CIN and promotes cellular transformation, which is consistent with a role in early CRC development.

MicroRNAs provide negative feedback and stability in gene regulatory network models of cell-state transitions

The development of multicellular organisms occurs through a series of cell state transitions controlled by gene regulatory networks. Central to these networks are transcription factors (TFs) which bind enhancers and activate the expression of other genes, some of which are also TFs. Gene regulatory networks (GRN) connect TFs and enhancers in a nonlinear circuit capable of producing complex behavior such as bifurcations between stable cell states. Our dynamic network modelling of the Embryonic Stem Cell (ESC) to Definitive Endoderm (DE) transition requires an as yet unknown negative feedback mechanism for stability. Here, we show that cell state specific microRNAs (miRNAs) can provide this negative feedback by inactivating other cell lineage determining TFs (ESC or DE) during the transition. Our model provides a mechanism to maintain stable cell states without requiring a large set of cell-type-specific repressive TFs, of which there are fewer known examples than activators. In support of this model, we use computational models and analyze gene and miRNA expression and chromatin accessibility data from human cell lines to detect enhancers activating the miRNAs consistent with our network model. Our analysis highlights the interplay between TFs and miRNAs during ESC to DE transition and proposes a novel model for gene regulation.

Forsythoside A mitigates osteoarthritis and inhibits chondrocyte senescence by promoting mitophagy and suppressing NLRP3 inflammasome via the Nrf2 pathway

BackgroundChondrocyte senescence and inflammation are hallmarks of osteoarthritis (OA). Forsythiaside A (FTA), a phenylethanol glycoside isolated from air-dried fruits of Forsythia, has been reported to have significant anti-inflammatory and antioxidant properties. However, its protective effects against OA have not been elucidated. PurposeWe explored the therapeutic efficacy of FTA in inhibiting chondrocyte senescence and inflammation during OA, as well as the potential underlying mechanisms. Study designThis study aimed to investigate the novel mechanism of FTA in alleviating OA in both cell and animal models. MethodsThe protective effect of FTA against tert-butyl hydroperoxide-induced chondrocyte damage was assessed, and the effects of FTA on cartilage aging and OA progression were evaluated using a medial meniscus (DMM)-induced knee OA mouse model. The regulatory effects of FTA on the NLRP3 Inflammasome, mitophagy, and the PKC/Nrf2 pathway were also explored. ResultsIn vitro, FTA improved mitochondrial function, enhanced mitophagy, suppressed NLRP3 inflammasome activation, and inhibited chondrocyte senescence; however, these chondroprotective effects were partially reversed after mitophagy inhibition, NLRP3 inflammasome activation, and Nrf2 pathway inhibition. Furthermore, we found that FTA directly interacts with Nrf2 and enhances its phosphorylation by protein kinase C (PKC). In vivo, FTA attenuated the pathological signs of knee OA in a DMM-model mouse model, which was partially reversed by ML385. ConclusionFTA inhibited chondrocyte senescence and OA progression by activating the PKC–Nrf2 pathway. Thus, FTA is a potential novel therapeutic agent for OA.

Antitumour activity of oleanolic acid: A systematic review and meta‑analysis.

Oleanolic acid (OA), a compound known for its potent antitumour properties, has been the subject of investigations in both cell and animal models. Although OA has good biological activity, its low water solubility and bioavailability limit its therapeutic use, and therefore translating the potential of OA into the clinical oncology setting remains challenging. The present systematic review and meta-analysis utilized evidence from animal model studies to gain insights into the antitumour mechanisms of OA to address the gap in understanding, and to provide guidance for future research directions and potential clinical applications. The guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses were applied in the present study and a comprehensive search was conducted across the PubMed/MEDLINE, Web of Science, Cochrane Library and Embase databases, with a cut-off date of June 30, 2023. The primary focus was on randomized controlled trials that used animal models to assess the antitumour effects of OA. The methodological quality appraisal was conducted using the Systematic Review Centre for Laboratory Animal Experimentation risk of bias tool, and tumour volume and weight served as the principal outcome measures. Data were analysed using the RevMan (version 5.3) and Stata SE11 software packages, with an assessment of heterogeneity conducted using the I2 statistical test, sensitivity analysis conducted using the leave-one-out approach, and evaluation of publication bias performed using Egger's test and funnel plot analysis. The present study demonstrated a significant inhibitory effect of OA intervention on tumour growth and a decrease in tumour weight in animal models. Despite the broad spectrum of antitumour effects exhibited by OA, further investigations are warranted to optimize the dosage and administration routes of OA to maximize its efficacy in clinical cancer treatment.

LRRK2 regulates production of reactive oxygen species in cell and animal models of Parkinson's disease.

Oxidative stress has long been implicated in Parkinson's disease (PD) pathogenesis, although the sources and regulation of reactive oxygen species (ROS) production are poorly defined. Pathogenic mutations in the gene encoding leucine-rich repeat kinase 2 (LRRK2) are associated with increased kinase activity and a greater risk of PD. The substrates and downstream consequences of elevated LRRK2 kinase activity are still being elucidated, but overexpression of mutant LRRK2 has been associated with oxidative stress, and antioxidants reportedly mitigate LRRK2 toxicity. Here, using CRISPR-Cas9 gene-edited HEK293 cells, RAW264.7 macrophages, rat primary ventral midbrain cultures, and PD patient-derived lymphoblastoid cells, we found that elevated LRRK2 kinase activity was associated with increased ROS production and lipid peroxidation and that this was blocked by inhibitors of either LRRK2 kinase or NADPH oxidase 2 (NOX2). Oxidative stress induced by the pesticide rotenone was ameliorated by LRRK2 kinase inhibition and was absent in cells devoid of LRRK2. In a rat model of PD induced by rotenone, a LRRK2 kinase inhibitor prevented the lipid peroxidation and NOX2 activation normally seen in nigral dopaminergic neurons in this model. Mechanistically, LRRK2 kinase activity was shown to regulate phosphorylation of serine-345 in the p47phox subunit of NOX2. This, in turn, led to translocation of p47phox from the cytosol to the membrane-associated gp91phox (NOX2) subunit, activation of the NOX2 enzyme complex, and production of ROS. Thus, LRRK2 kinase activity may drive cellular ROS production in PD through the regulation of NOX2 activity.

ZIC2 and ZIC3 promote SWI/SNF recruitment to safeguard progression towards human primed pluripotency

The primed epiblast acts as a transitional stage between the relatively homogeneous naïve epiblast and the gastrulating embryo. Its formation entails coordinated changes in regulatory circuits driven by transcription factors and epigenetic modifications. Using a multi-omic approach in human embryonic stem cell models across the spectrum of peri-implantation development, we demonstrate that the transcription factors ZIC2 and ZIC3 have overlapping but essential roles in opening primed-specific enhancers. Together, they are essential to facilitate progression to and maintain primed pluripotency. ZIC2/3 accomplish this by recruiting SWI/SNF to chromatin and loss of ZIC2/3 or degradation of SWI/SNF both prevent enhancer activation. Loss of ZIC2/3 also results in transcriptome changes consistent with perturbed Polycomb activity and a shift towards the expression of genes linked to differentiation towards the mesendoderm. Additionally, we find an intriguing dependency on the transcriptional machinery for sustained recruitment of ZIC2/3 over a subset of primed-hESC specific enhancers. Taken together, ZIC2 and ZIC3 regulate highly dynamic lineage-specific enhancers and collectively act as key regulators of human primed pluripotency.

Solar methanol production from carbon dioxide and water using NaA zeolitic membrane reactor with pressurized solid oxide electrolysis cell

Solar-driven methanol synthesis coupled with water electrolysis can achieve carbon-negative methanol production. In this study, a solar methanol production system using water-conduction membrane reactor coupled with pressurized solid oxide electrolysis cell is proposed. A methanol synthesis membrane reactor model and a solar-driven pressurized solid oxide electrolysis cell model are developed and validated. Under the specified conditions, the conversion efficiency of the membrane reactor is found to be twice as high as that of a conventional reactor. A thermodynamic model is developed to simulate the system's performance. Using this model, the energy flows within the system are visually represented through a Sankey diagram, providing a clear illustration of energy distribution and losses. Additionally, effects of the solid oxide electrolysis cell temperature, current density, methanol synthesis temperature and pressure on the system performance are investigated parametrically. An optimum solar-to-methanol efficiency of 7.3 % is obtained. Furthermore, the economic analysis shows the levelized cost of methanol close to 1.40 Euro/kg and the payback period is around 4.5 years. This study proposed a novel efficient solar methanol production system.

Using Acanthamoeba spp. as a cell model to evaluate Leishmania infections.

Leishmaniasis represents a severe global health problem. In the last decades, there have been significant challenges in controlling this disease due to the unavailability of licensed vaccines, the high toxicity of the available drugs, and an unrestrained surge of drug-resistant parasites, and human immunodeficiency virus (HIV)-Leishmania co-infections. Leishmania spp. preferentially invade macrophage lineage cells of vertebrates for replication after subverting cellular functions of humans and other mammals. These early events in host-parasite interactions are likely to influence the future course of the disease. Thus, there is a continuing need to discover a simple cellular model that reproduces the in vivo pathogenesis. Acanthamoeba spp. are non-mammalian phagocytic amoeba with remarkable similarity to the cellular and functional aspects of macrophages. We aimed to assess whether the similarity reported between macrophages and Acanthamoeba spp. is sufficient to reproduce the infectivity of Leishmania spp. Herein, we analyzed co-cultures of Acanthamoeba castellanii or Acanthamoeba polyphaga with Leishmania infantum, Leishmania amazonensis, Leishmania major, and Leishmania braziliensis. Light and fluorescence microscopy revealed that the flagellated promastigotes attach to the A. castellanii and/or A. polyphaga in a bipolar and or random manner, which initiates their uptake via pseudopods. Once inside the cells, the promastigotes undergo significant changes, which result in the obligatory amastigote-like intracellular form. There was a productive infection with a continuous increase in intracellular parasites. However, we frequently observed intracellular amastigotes in vacuoles, phagolysosomes, and the cytosol of Acanthamoeba spp. Our findings corroborate that Leishmania spp. infects Acanthamoeba spp. and replicates in them but does not cause their rapid degeneration or lysis. Overall, the evidence presented here confirms that Acanthamoeba spp. have all prerequisites and can help elucidate how Leishmania spp. infect mammalian cells. Future work exposing the mechanisms of these interactions should yield novel insights into how these pathogens exploit amoebae.

Integrin subunit beta 6 is a potential diagnostic marker for acute kidney injury in patients with diabetic kidney disease: a single cell sequencing data analysis

Background Diabetic kidney disease (DKD), a prevalent complication of diabetes mellitus, is often associated with acute kidney injury (AKI). Thus, the development of preventive and therapeutic strategies is crucial for delaying the progression of AKI and DKD. Methods The GSE183276 dataset, comprising the data of 20 healthy controls and 12 patients with AKI, was downloaded from the Gene Expression Omnibus (GEO) database to analyze the AKI group. For analyzing the DKD group, the GSE131822 dataset, comprising the data of 3 healthy controls and 3 patients with DKD, was downloaded from the GEO database. The common differentially expressed genes (DEGs) in renal tubular epithelial cells (TECs) were subjected to enrichment analyses. Next, a protein-protein interaction (PPI) network was constructed using the Search Tool for the Retrieval of Interacting Genes database to analyze gene-related regulatory networks. Finally, the AKI animal models and the DKD and AKI cell models were established, and the reliability of the identified genes was validated using quantitative real-time polymerase chain reaction analysis. Results Functional analysis was performed with 40 common DEGs in TECs. Eight hub genes were identified using the PPI and gene-related networks. Finally, validation experiments with the in vivo animal model and the in vitro cellular model revealed the four common DEGs. Four DEGs that share molecular mechanisms in the pathogenesis of DKD and AKI were identified. In particular, the expression of Integrin Subunit Beta 6(ITGB6), a hub and commonly upregulated gene, was upregulated in the in vitro models. Conclusion ITGB6 may serve as a biomarker for early AKI diagnosis in patients with DKD and as a target for early intervention therapies.

NMR-Based Stable Isotope Tracing of Cancer Metabolism.

NMR is widely used for metabolite profiling (metabolomics, metabonomics) particularly of various readily obtainable biofluids such as plasma and urine. It is especially valuable for stable isotope tracer studies to track metabolic pathways under control or perturbed conditions in a wide range of cell models as well as animal models and human subjects. NMR has unique properties for utilizing stable isotopes to edit or simplify otherwise complex spectra acquired in vitro and in vivo, while quantifying the level of enrichment at specific atomic positions in various metabolites (i.e., isotopomer distribution analysis).In this protocol, we give an overview with specific protocols for NMR-based stable isotope-resolved metabolomics, or SIRM, with a workflow from administration of isotope-enriched precursors, via sample preparation through to NMR data collection and reduction. We focus on indirect detection of common NMR-active stable isotopes including 13C, 15N, 31P, and 2H, using a variety of 1H-based two-dimensional experiments. We also include the application and analyses of multiplex tracer experiments.

Lactylation of nuclear receptor coactivator 4 promotes ferritinophagy and glycolysis of neuronal cells after cerebral ischemic injury.

Ischemic stroke remains a major cause of disability and mortality. Nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy is involved in cerebral ischemic injury. Additionally, lactylation regulates the progression of ischemia injury. This study aimed to investigate the impact of NCOA4 on ferritinophagy and glycolysis of hippocampal neuron cells and its lactylation modification. Middle cerebral artery occlusion (MCAO) mouse and oxygen-glucose deprivation (OGD)-treated HT22 cell models were generated. Ferritinophagy was evaluated via detecting ferrous iron (Fe 2+ ), glutathione, malondialdehyde, and protein levels. Glycolysis was assessed by examining the glucose consumption, lactate production, and extracellular acidification rate. The lactylation was evaluated using immunoprecipitation and immunoblotting. Brain injury in vivo was analyzed by measuring brain infarct and neurological function. The results showed that NCOA4 expression was increased in the blood of patients with acute ischemia stroke, the peri-infarct region of the brain in MCAO mice (increased percentage: 142.11%) and OGD-treated cells (increased percentage: 114.70%). Knockdown of NCOA4 inhibited ferritinophagy and glycolysis of HT22 cells induced by OGD. Moreover, OGD promoted the lactylation of NCOA4 at lysine (K)450 sites, which enhanced NCOA4 protein stability. Additionally, interfering with NCOA4 attenuated brain infarction and neurological dysfunction in MCAO mice. Lactylation of NCOA4 at K450 sites promotes ferritinophagy and glycolysis of hippocampal neuron cells, thereby accelerating cerebral ischemic injury. These findings suggest a novel pathogenesis of ischemic stroke.

Influence of concentration on thermophoresis of spherical aerosol particles within a Brinkman medium

Abstract We are examining the thermophoretic movement of a uniform mixture of spherical aerosol particles, all with the same properties, as they are situated within a porous material. These particles can have various thermal conductivity and surface characteristics. This analysis focuses on situations where the Péclet and Reynolds numbers are small. The influence of particle interactions is carefully considered by using a unit cell model, a well-established method known for its accurate predictions in the context of sedimentation for monodisperse suspensions of spherical particles. The porous medium is represented as a Brinkman fluid characterized by a Darcy permeability, which can be determined directly from experimental observations. This medium is considered to be uniform and isotropic, and the solid matrix is in thermal equilibrium with the fluid flowing through the voids of the medium. The Knudsen number is assumed to be low, enabling the description of fluid flow through the porous medium using a continuum model that includes temperature jump, thermal creep, frictional slip, and thermal stress slip at the aerosol particle’s surface. The conservation equations for energy and momentum are individually tackled within each cell. In this model, each cell represents a spherical particle enclosed by a concentric shell of surrounding fluid. The thermophoretic particle migration velocity is determined across different cases. We derive analytical expressions for this average particle velocity, expressing it in terms of the particle volume fraction. It is observed that different cell models yield somewhat varied results for particle velocity. Generally, with a fixed permeability parameter characterizing the porous medium, an increase in the thermal stress slip coefficient tends to decrease the normalized thermophoretic velocity across the different cell models. The results are in good agreement with the available data as documented in the existing literature. Additionally, a parallel examination of aerosol sphere sedimentation is provided.

Neuroglobin protects dopaminergic neurons in a Parkinson’s cell model by interacting with mitochondrial complex NDUFA10

The study aimed to validate the protective effect of neuroglobin (Ngb) in a cell model of Parkinson’s disease (PD) and explore its therapeutic potential. Lentivirus-Ngb (LvNgb) and siRNA-Ngb (siNgb) were used to achieve Ngb overexpression and knockdown, respectively, in a sporadic PD cell model. Apoptosis was evaluated by flow cytometry-based Annexin V/propidium iodide assays. Activation of the pro-apoptotic factor, Caspase-9, was detected by immunoblotting, and Complex I activities were detected by using enzyme-linked immunosorbent assay (ELISA). Mitochondrial dysfunction was examined by measuring the mitochondrial membrane potential (MMP), NAD+/NADH ratios, and reactive oxygen species (ROS) levels. Additionally, coimmunoprecipitation (Co-IP) assays were conducted in mouse neuroblastoma cell line 9D (MN9D) cells to determine the interactions of Ngb with the Complex I subunit NDUFA10. The results showed that Ngb overexpression reduced the percentages of apoptotic cells, total caspase-9 levels and restored Complex I activities in the PD cell model. Conversely, knockdown of Ngb resulted in an increase in apoptotic cells, higher total caspase-9 levels, and decreased Complex I activities. Furthermore, Ngb overexpression restored MMP and NAD+/NADH ratios and alleviated ROS-mediated oxidative stress in MN9D cells. Finally, Co-IP confirmed the interaction between Ngb and NDUFA10 in MN9D cells. In conclusion, Ngb protects MN9D cells against apoptosis by interacting with Complex I subunit NDUFA10, rescuing its activity and inhibiting the mitochondrial pathway of apoptosis in the MPP+-mediated PD model.

Neuroinflammation inhibition and neuroprotective effects of purpurin, a potential anti-AD compound, screened via network proximity and gene enrichment analyses.

Alzheimer's disease (AD) is a complex neurodegenerative disease without any effective preventive or therapeutic drugs. Natural products with stable structures and pharmacological characteristics are valuable sources for the development of novel drugs for many complex diseases. This study aimed to discover potential natural compounds for the treatment of AD using new technologies and methods and explore the efficacy and mechanism of candidate compounds. AD-related large-scale genetic datasets were collated to construct disease-PPIs and natural products were collected from six databases to construct compound-protein interactions (CPIs). Potential relationships between natural compounds and AD were predicted via network proximity and gene enrichment analyses. Then, five AD-related cell models and d-galactose-induced aging rat model were established to evaluate the neuroprotective effects of candidate compounds in vitro and in vivo. We identified that 267 natural compounds were predicted to have close connections with AD and 19 compounds could exert protective effect in at least one cell model. Notably, purpurin exerted protective effect in three cell models and significantly improved the cognitive learning and memory functions, reduced the oxidative stress injuries and neuroinflammation, and enhanced the synaptic plasticity and neurotrophic effect in the brain of d-galactose-treated rats. In this study, AD-related natural compounds were identified via network proximity and gene enrichment analyses. In vivo and in vitro experiments revealed the therapeutic potential of purpurin for AD treatment, laying the foundation for further in-depth research and providing valuable information for the development of novel anti-AD drugs.

Role of Bβ1 overexpression in the pathogenesis of SCA12.

Spinocerebellar ataxia type 12 (SCA12) is a neurodegenerative disease caused by a CAG/CTG repeat expansion at the PPP2R2B locus. We investigated how the CAG repeat expansion within the PPP2R2B 7B7D transcript influences the expression of Bβ1 and a potential protein containing a long polyserine tract. Transcript and protein expression were measured using quantitative PCR (qPCR) and Western blot, respectively, in an SK-N-MC cell model that overexpresses the full-length PPP2R2B 7B7D transcript. The apoptotic effect of a protein containing a long polyserine tract on SK-N-MC cells was evaluated using caspase 3/7 activity. The CAG repeat expansion increases the expression of the PPP2R2B 7B7D transcript, as well as Bβ1 protein, in an SK-N-MC cell model in which the full-length PPP2R2B 7B7D transcript is overexpressed. The CAG repeat expansion within the 7B7D transcript is translated into a long polyserine tract that triggers apoptosis in SK-N-MC cells. The SCA12 mutation leads to overexpression of PPP2R2B Bβ1 and to expression of a protein containing a long polyserine tract; both these effects potentially contribute to SCA12 pathogenesis. © 2024 International Parkinson and Movement Disorder Society.

Ameliorating Effect of S-Allyl Cysteine (Black Garlic) on 6-OHDA Mediated Neurotoxicity in SH-SY5Y Cell Line

Therapeutic approaches based on isolated compounds derived from natural products are more common in preventing diseases involving inflammation and oxidative stress at present. S-allyl cysteine (SAC) is a promising garlic-derived organosulfur compound with many positive effects in cell models and living systems. SAC has biological activity in various fields, enclosing healing in learning and memory disorders, neurotrophic effects, and antioxidant activity. In this study, we purposed to identify the neuroprotective activity of SAC toward 6-OHDA-induced cell demise in the SH-SY5Ycell line. For this purpose, 6-OHDA-induced cytotoxicity, and biochemical, and gene expression changes were evaluated in SH-SY5Y cells. SH-SY5Y cells grown in cell culture were treated with SAC 24hours before and after 6-OHDA application. Then, cell viability, antioxidant parameters, and gene expressions were measured. Finally, immunofluorescence staining analysis was performed. Our results showed that SAC increased cell viability by 144% at 80µg/mL with pre-incubation (2hours). It was observed that antioxidant levels were significantly increased and oxidative stress marker levels were decreased in cells exposed to 6-OHDA after pre-treatment with SAC (p<0.05). SAC supplementation also suppressed the increase in pro-inflammation levels (TNF-α/IL1/IL8) caused by 6-OHDA (p < 0.05). While 8-OHdG and Nop10 expressions were observed at a mild level in SAC pretreatment depending on the dose, 8-OHdG, and Nop10 expressions were observed at a moderate level in SAC treatment after 6-OHDA application (p<0.05). Our findings demonstrate the positive effect of pretreatment with SAC on SH-SY5Y cells injured by 6-OHDA, suggesting that SAC may be beneficial for neuroprotection in regulating oxidative stress and neuronal survival in an in vitro model of Parkinson's disease.