Early short-term hypoxia promotes epidermal cell migration by activating the CCL2-ERK1/2 pathway and epithelial-mesenchymal transition during wound healing.

Background: Due to vasculature injury and increased oxygen consumption, the early wound microenvironment is typically in a hypoxic state. We observed enhanced cell migration ability under early short-term hypoxia. CCL2 belongs to the CC chemokine family and was found to be increased in early hypoxic wounds and enriched in the extracellular signal-regulated kinase (ERK)1/2 pathway in our previous study. However, the underlying mechanism through which the CCL2-ERK1/2 pathway regulates wound healing under early short-term hypoxia remains unclear. Activation of epithelial-mesenchymal transition (EMT) is a key process in cancer cell metastasis, during which epithelial cells acquire the characteristics of mesenchymal cells and enhance cell motility and migration ability. However, the relationship between epithelial cell migration and EMT under early short-term hypoxia has yet to be explored. Methods: HaCaT cells were cultured to verify the effect of early short-term hypoxia on migration through cell scratch assays. Lentiviruses with silenced or overexpressed CCL2 were used to explore the relationship between CCL2 and migration under short-term hypoxia. An acute full-thickness cutaneous wound rat model was established with the application of an ERK inhibitor to reveal the hidden role of the ERK1/2 pathway in the early stage of wound healing. The EMT process was verified in all the above experiments through western blotting. Results: In our study, we found that short-term hypoxia promoted cell migration. Mechanistically, hypoxia promoted cell migration through mediating CCL2. Overexpression of CCL2 via lentivirus promoted cell migration, while silencing CCL2 via lentivirus inhibited cell migration and the production of related downstream proteins. In addition, we found that CCL2 was enriched in the ERK1/2 pathway, and the application of an ERK inhibitor in vivo and in vitro verified the upstream and downstream relationships between the CCL2 pathway and ERK1/2. Western blot results both in vivo and in vitro demonstrated that early short-term hypoxia promotes epidermal cell migration by activating the CCL2-ERK1/2 pathway and EMT during wound healing. Conclusions: Our work demonstrated that hypoxia in the early stage serves as a stimulus for triggering wound healing through activating the CCL2-ERK1/2 pathway and EMT, which promote epidermal cell migration and accelerate wound closure. These findings provide additional detailed insights into the mechanism of wound healing and new targets for clinical treatment.

[Role and mechanism of cysteine and glycine-rich protein 2 in the malignant progression of neuroblastoma].

OBJECTIVE: To investigate the function and underlying mechanism of cysteine and glycine-rich protein 2 (CSRP2) in neuroblastoma (NB). METHODS: The correlation between the expression level of CSRP2 mRNA and the prognosis of NB children in NB clinical samples was analyzed in R2 Genomics Analysis and Visualization Platform. The small interfering RNA (siRNA) targeting CSRP2 or CSRP2 plasmid were transfected to NB cell lines SK-N-BE(2) and SH-SY5Y. Cell proliferation was observed by crystal violet staining and real-time cellular analysis. The ability of colony formation of NB cells was observed by colony-forming unit assay. Immunofluorescence assay was used to detect the expression of the proliferation marker Ki-67. Flow cytometry analysis for cell cycle proportion was used with cells stained by propidium iodide (PI). Annexin V/7AAD was used to stain cells and analyze the percentage of cell apoptosis. The ability of cell migration was determined by cell wound-healing assay. The level of protein and mRNA expression of CSRP2 in NB primary tumor and NB cell lines were detected by Western blot and quantitative real-time PCR (RT-qPCR). RESULTS: By analyzing the NB clinical sample databases, it was found that the expression levels of CSRP2 in high-risk NB with 3/4 stages in international neuroblastoma staging system (INSS) were significantly higher than that in low-risk NB with 1/2 INSS stages. The NB patients with high expression levels of CSRP2 were shown lower overall survival rate than those with low expression levels of CSRP2. We detected the protein levels of CSRP2 in the NB samples by Western blot, and found that the protein level of CSRP2 in 3/4 INSS stages was significantly higher than that in 1/2 INSS stages. Knockdown of CSRP2 inhibited cell viability and proliferation of NB cells. Overexpression of CSRP2 increased the proliferation of NB cells. Flow cytometry showed that the proportion of sub-G1, G0/G1 and S phase cells and Annexin V positive cells were increased after CSRP2 deficiency. In the cell wound-healing assay, the healing rate of NB cells was significantly attenuated after knockdown of CSRP2. Further mechanism studies showed that the proportion of the proliferation marker Ki-67 and the phosphorylation levels of extracellular signal-regulated kinases 1/2 (ERK1/2) were significantly decreased after CSRP2 knockdown. CONCLUSION: CSRP2 is highly expressed in high-risk NB with 3/4 INSS stages, and the expression levels of CSRP2 are negatively correlated with the overall survival of NB patients. CSRP2 significantly increased the proliferation and cell migration of NB cells and inhibited cell apoptosis via the activation of ERK1/2. All these results indicate that CSRP2 promotes the progression of NB by activating ERK1/2, and this study will provide a potential target for high-risk NB therapy.

MAPK pathway orchestrates gallid alphaherpesvirus 1 infection through the biphasic activation of MEK/ERK and p38 MAPK signaling.

Therapies targeting virus-host interactions are seen as promising strategies for treating gallid alphaherpesvirus 1 (ILTV) infection. Our study revealed a biphasic activation of two MAPK cascade pathways, MEK/ERK and p38 MAPK, as a notably activated host molecular event in response to ILTV infection. It exhibits antiviral functions at different stages of infection. Initially, the MEK/ERK pathway is activated upon viral invasion, leading to a broad suppression of metabolic pathways crucial for ILTV replication, thereby inhibiting viral replication from the early stage of ILTV infection. As the viral replication progresses, the p38 MAPK pathway activates its downstream transcription factor, STAT1, further hindering viral replication. Interestingly, ILTV overcomes this biphasic antiviral barrier by hijacking host p38-AKT axis, which protects infected cells from the apoptosis induced by infection and establishes an intracellular equilibrium conducive to extensive ILTV replication. These insights could provide potential therapeutic targets for ILTV infection.

Neurotrophin-3 Rescues Striatal Synaptic Plasticity in Model of Neurodegeneration by PLC Signaling Activation.

BACKGROUND: Neurotrophins are essential factors for neural growth and function; they play a crucial role in neurodegenerative diseases where their expression levels are altered. Our previous research has demonstrated changes in synaptic plasticity and neurotrophin expression levels in a pharmacological model of Huntington's disease induced by 3-nitropropionic acid (3-NP). In the 3- NP-induced HD model, corticostriatal Long Term Depression (LTD) was impaired, but neurotrophin-3 (NT-3) restored striatal LTD. This study delves into the NT-3-induced signaling pathways involved in modulating and restoring striatal synaptic plasticity in cerebral slices from 3-NPinduced striatal degeneration in mice in vivo. METHODS: Phospholipase C (PLC), phosphatidylinositol-3-kinase (PI3K), and mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathways activated by NT-3 were analyzed by means of field electrophysiological recordings in brain slices from control and 3-NP treated in the presence of specific inhibitors of the signaling pathways. RESULTS: Using specific inhibitors, PLC, PI3K, and MEK/ERK signaling pathways contribute to NT3-mediated plasticity modulation in striatal tissue slices recorded from control animals. However, in the neurodegeneration model induced by 3-NP, the recovery of striatal LTD induced by NT-3 was prevented only by the PLC inhibitor. Moreover, the PLC signaling pathway appeared to trigger downstream activation of the endocannabinoid system, evidenced by AM 251, an inhibitor of the CB1 receptor, also hindered NT-3 plasticity recovery. CONCLUSION: Our finding highlights the specific involvement of the PLC pathway in the neuroprotective effects of NT-3 in mitigating synaptic dysfunction under neurodegenerative conditions.

Pleiotropic attenuating effect of Ginkgo biloba against isoprenaline-induced myocardial infarction via improving Bcl-2/mTOR/ERK1/2/Na+, K+-ATPase activities.

Objective: Myocardial infarction (MI) is linked to an imbalance in the supply and demand of blood oxygen in the heart muscles. Beta-blockers and calcium antagonists are just two of the common medications used to treat MI. However, these have reportedly been shown to be either ineffective or to have undesirable side effects. Extract of Ginkgo biloba leaves (GBE), a Chinese herbal product offers special compatibility benefits in therapeutic settings relating to inflammatory diseases and oxidative stress. In order to better understand how GBE affects MI in rats insulted by isoprenaline (ISO), the current study was designed. Methods: The heart weight index, serum lipid profile, cardiac marker enzymes, endogenous antioxidants [catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), nitrites and malondialdehyde (MDA)], inflammatory mediators [tumour necrosis factor alpha (TNF-α) and interleukin-6 (IL-6)], immunohistochemical expressions of B-cell lymphoma factor-2 (Bcl-2), extracellular signal-regulated kinase (ERK1/2), and mammalian target of rapamycin (mTOR) and histopathological analysis were used to assess the cardioprotective properties of GBE. Results: The findings showed that GBE effectively attenuated myocardial infarction by boosting the body's natural antioxidant defense system and reducing the release of inflammatory cytokines as well as heart injury marker enzymes. The expression of Bcl-2, ERK1/2 and mTOR was increased while the histomorphological alterations were reversed. Conclusion: The cardioprotective effects of GBE may be due to a mechanism involving increased Bcl-2/mTOR/ERK1/2/Na+, K+-ATPase activity.

[Retracted] Downregulation of CKS1B restrains the proliferation, migration, invasion and angiogenesis of retinoblastoma cells through the MEK/ERK signaling pathway.

Following the publication of the above paper, it has been drawn to the Editors' attention by a concerned reader that certain of the lumen formation assay data shown in Fig. 5A on p. 112 were strikingly similar to data appearing in different form in another article written by different authors at different research institute, which had already been published in the journal Biomedicine & Pharmacotherapy prior to the submission of this paper to International Journal of Molecular Medicine, and which has also subsequently been retracted. In view of the fact that the contentious data had already apparently been published previously, the Editor of International Journal of Molecular Medicine has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [International Journal of Molecular Medicine 44: 103­114, 2019; DOI: 10.3892/ijmm.2019.4183].

Orexin B protects dopaminergic neurons from 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity associated with reduced extracellular signal-regulated kinase phosphorylation.

BACKGROUND: The loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) is a major pathological hallmark of Parkinson's disease (PD). Orexin B (OXB) has been reported to promote the growth of DA neurons. However, the roles of OXB in the degeneration of DA neurons still remained not fully clear. METHODS: An in vivo PD model was constructed by administrating 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice. Pole test was performed to investigate the motor function of mice and the number of DA neurons was detected by immunofluorescence (IF). A PD cell model was established by treating SH-SY5Y cells with 1-methyl-4-phenylpyridinium (MPP+). OXB was added to the culture medium 2 h after MPP + treatment. Microscopic analysis was carried out to investigate the function of OXB in the cell model of PD 24 h after MPP + challenge. RNA-Seq analysis of the PD cell model was performed to explore the possible mechanisms. Western blot was used to detect the phosphorylation levels of extracellular signal-regulated kinase (ERK). RESULTS: OXB significantly decreased the DA neurons death caused by MPTP, alleviated MPP+-induced neurotoxicity in SH-SY5Y cells, and robustly enhanced the weight and motor ability of PD mice. Besides, RNA-Seq analysis demonstrated that the mitogen-activated protein kinase (MAPK) pathway was involved in the pathology of PD. Furthermore, MPP + led to increased levels of phosphorylation of ERK (p-ERK), OXB treatment significantly decreased the levels of p-ERK in MPP+-treated SH-SY5Y cells. CONCLUSIONS: This study demonstrated that OXB exerts a neuroprotective role associated with reduced ERK phosphorylation in the PD model. This suggests that OXB may have therapeutic potential for treatment of PD.

MiRNA-145-5p inhibits gastric cancer progression via the serpin family E member 1- extracellular signal-regulated kinase-1/2 axis.

BACKGROUND: MicroRNAs (miRNAs) regulate gene expression and play a critical role in cancer physiology. However, there is still a limited understanding of the function and regulatory mechanism of miRNAs in gastric cancer (GC). AIM: To investigate the role and molecular mechanism of miRNA-145-5p (miR145-5p) in the progression of GC. METHODS: Real-time polymerase chain reaction (RT-PCR) was used to detect miRNA expression in human GC tissues and cells. The ability of cancer cells to migrate and invade was assessed using wound-healing and transwell assays, respectively. Cell proliferation was measured using cell counting kit-8 and colony formation assays, and apoptosis was evaluated using flow cytometry. Expression of the epithelial-mesenchymal transition (EMT)-associated protein was determined by Western blot. Targets of miR-145-5p were predicated using bioinformatics analysis and verified using a dual-luciferase reporter system. Serpin family E member 1 (SERPINE1) expression in GC tissues and cells was evaluated using RT-PCR and immunohistochemical staining. The correlation between SERPINE1 expression and overall patient survival was determined using Kaplan-Meier plot analysis. The association between SERPINE1 and GC progression was also tested. A rescue experiment of SERPINE1 overexpression was conducted to verify the relationship between this protein and miR-145-5p. The mechanism by which miR-145-5p influences GC progression was further explored by assessing tumor formation in nude mice. RESULTS: GC tissues and cells had reduced miR-145-5p expression and SERPINE1 was identified as a direct target of this miRNA. Overexpression of miR-145-5p was associated with decreased GC cell proliferation, invasion, migration, and EMT, and these effects were reversed by forcing SERPINE1 expression. Kaplan-Meier plot analysis revealed that patients with higher SERPINE1 expression had a shorter survival rate than those with lower SERPINE1 expression. Nude mouse tumorigenesis experiments confirmed that miR-145-5p targets SERPINE1 to regulate extracellular signal-regulated kinase-1/2 (ERK1/2). CONCLUSION: This study found that miR-145-5p inhibits tumor progression and is expressed in lower amounts in patients with GC. MiR-145-5p was found to affect GC cell proliferation, migration, and invasion by negatively regulating SERPINE1 levels and controlling the ERK1/2 pathway.

Beneficial effect of heat-killed Lactiplantibacillus plantarum L-137 on intestinal barrier function of rat small intestinal epithelial cells.

Heat-killed Lactiplantibacillus plantarum L-137 (HK L-137) has been suggested to enhance the intestinal barrier in obese mice, leading to improvement of metabolic abnormalities and adipose tissue inflammation, and in healthy humans with overweight, leading to improvement of systemic inflammation. However, its detailed mechanism of action has not been clarified. Therefore, this study investigated the effects of HK L-137 on the permeability of rat small intestinal epithelial IEC-6 cells, tight junction-related gene and protein expression and localization, and intracellular signaling pathways involved in barrier function. Treatment of IEC-6 cells with HK L-137 for 26 h significantly reduced the permeability to fluorescein isothiocyanate-dextran (FD-4). HK L-137 also increased gene and protein expression of zonula occludens-1 (ZO-1), an important tight junction protein, without affecting the localization. Furthermore, inhibition of the extracellular signal-regulated kinase (ERK)1/2 pathway in IEC-6 cells canceled the HK L-137-related reduction in permeability to FD-4. Phosphorylation of ERK in IEC-6 cells was induced 15 min after the addition of HK L-137. These results suggest that HK L-137 reduces intestinal permeability partly through activating the ERK pathway and increasing expression of the ZO-1 gene and protein. Enhancement of intestinal barrier function with HK L-137 might be effective in preventing and treating leaky gut, for which no specific therapeutic tool has been established.

Particulate matter (PM10) exacerbates on MK-801-induced schizophrenia-like behaviors through the inhibition of ERK-CREB-BDNF signaling pathway.

Particulate matter (PM), released into the air by a variety of natural and human activities, is a key indicator of air pollution. Although PM is known as the extensive health hazard to affect a variety of illness, few studies have specifically investigated the effects of PM10 exposure on schizophrenic development. In the present study, we aimed to investigate the impact of PM10 on MK-801, N-methyl-D-aspartate (NMDA) receptor antagonist, induced schizophrenia-like behaviors in C57BL/6 mouse. Preadolescent mice were exposed PM10 to 3.2 mg/m3 concentration for 4 h/day for 2 weeks through a compartmentalized whole-body inhalation chamber. After PM10 exposure, we conducted behavioral tests during adolescence and adulthood to investigate longitudinal development of schizophrenia. We found that PM10 exacerbated schizophrenia-like behavior, such as psychomotor agitation, social interaction deficits and cognitive deficits at adulthood in MK-801-induced schizophrenia animal model. Furthermore, the reduced expression levels of brain-derived neurotrophic factor (BDNF) and the phosphorylation of BDNF related signaling molecules, extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB), were exacerbated by PM10 exposure in the adult hippocampus of MK-801-treated mice. Thus, our present study demonstrates that exposure to PM10 in preadolescence exacerbates the cognitive impairment in animal model of schizophrenia, which are considered to be facilitated by the decreased level of BDNF through reduced ERK-CREB expression.

ELABELA-derived peptide ELA13 attenuates kidney fibrosis by inhibiting the Smad and ERK signaling pathways. / ELABELA衍生肽ELA13通过抑制Smad和ERK信号通路减轻肾纤维化.

Kidney fibrosis is an inevitable result of various chronic kidney diseases (CKDs) and significantly contributes to end-stage renal failure. Currently, there is no specific treatment available for renal fibrosis. ELA13 (amino acid sequence: RRCMPLHSRVPFP) is a conserved region of ELABELA in all vertebrates; however, its biological activity has been very little studied. In the present study, we evaluated the therapeutic effect of ELA13 on transforming growth factor-ß1 (TGF-ß1)-treated NRK-52E cells and unilateral ureteral occlusion (UUO) mice. Our results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum, and reduce the expression of fibrosis biomarkers confirmed by Masson staining, immunohistochemistry, real-time polymerase chain reaction (RT-PCR), and western blot. Inflammation biomarkers were increased after UUO and decreased by administration of ELA13. Furthermore, we found that the levels of essential molecules in the mothers against decapentaplegic (Smad) and extracellular signal-regulated kinase (ERK) pathways were reduced by ELA13 treatment in vivo and in vitro. In conclusion, ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.

RAMP1 Protects Hepatocytes against Ischemia-reperfusion Injury by Inhibiting the ERK/YAP Pathway.

Background and Aims: Hepatic ischemia-reperfusion injury (HIRI) is a prevalent complication of liver transplantation, partial hepatectomy, and severe infection, necessitating the development of more effective clinical strategies. Receptor activity-modifying protein 1 (RAMP1), a member of the G protein-coupled receptor adapter family, has been implicated in numerous physiological and pathological processes. The study aimed to investigate the pathogenesis of RAMP1 in HIRI. Methods: We established a 70% liver ischemia-reperfusion model in RAMP1 knockout (KO) and wild-type mice. Liver and blood samples were collected after 0, 6, and 24 h of hypoxia/reperfusion. Liver histological and serological analyses were performed to evaluate liver damage. We also conducted in-vitro and in-vivo experiments to explore the molecular mechanism underlying RAMP1 function. Results: Liver injury was exacerbated in RAMP1-KO mice compared with the sham group, as evidenced by increased cell death and elevated serum transaminase and inflammation levels. HIRI was promoted in RAMP1-KO mice via the induction of hepatocyte apoptosis and inhibition of proliferation. The absence of RAMP1 led to increased activation of the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway and yes-associated protein (YAP) phosphorylation, ultimately promoting apoptosis. SCH772984, an ERK/MAPK phosphorylation inhibitor, and PY-60, a YAP phosphorylation inhibitor, reduced apoptosis in in-vitro and in-vivo experiments. Conclusions: Our findings suggest that RAMP1 protects against HIRI by inhibiting ERK and YAP phosphorylation signal transduction, highlighting its potential as a therapeutic target for HIRI and providing a new avenue for intervention.

[PI3K/Akt/Erk signaling pathway mediates neuroprotection of CaMK⠡γ and CaMK⠡δ against ischemic reperfusion injury in mice].

OBJECTIVE: To observe neuroprotective effects of Ca2+/calmodulin-dependent kinase Ⅱ (CaMK Ⅱ)γ and CaMkII δ against acute neuronal ischemic reperfusion injury in mice and explore the underlying mechanism. METHODS: Primary cultures of brain neurons isolated from fetal mice (gestational age of 18 days) were transfected with two specific siRNAs (si-CAMK2G and si-CAMK2D) or a control sequence (si-NT). After the transfection, the cells were exposed to oxygen-glucose deprivation/reperfusion (OGD/R) conditions for 1 h followed by routine culture. The expressions of phosphatidylinositol-3-kinase/extracellular signal-regulated kinase (PI3K/Akt/Erk) signaling pathway components in the neurons were detected using immunoblotting. The expressions of the PI3K/Akt/Erk signaling pathway proteins were also detected in the brain tissues of mice receiving middle cerebral artery occlusion (MCAO) or sham operation. RESULTS: The neuronal cells transfected with siCAMK2G showed significantly lower survival rates than those with si-NT transfection at 12, 24, 48, and 72 h after OGD/R (P < 0.01), and si-CAMK2G transfection inhibited OGD/R-induced upregulation of CaMKⅡγ expression. Compared to si-NT, transfection with si-CAMK2G and si-CAMK2D both significantly inhibited the expressions of PI3K/Akt/Erk signaling pathway components (P < 0.01). In the mouse models of MCAO, the expressions of CaMKⅡδ and CaMKⅡγ were significantly increased in the brain, where activation of the PI3K/Akt/Erk signaling pathway was detected. The expression levels of CaMKⅡδ, CaMKⅡγ, Erk, phosphorylated Erk, Akt, and phosphorylated Akt were all significantly higher in MCAO mice than in the sham-operated mice at 24, 48, 72, and 96 h after reperfusion (P < 0.05). CONCLUSION: The neuroprotective effects of CaMKⅡδ and CaMKⅡγ against acute neuronal ischemic reperfusion injury are mediated probably by the PI3K/Akt/Erk pathway.

Farnesoid X receptor modulator 12ß-(m-methyl-benzoyl)-11,12-dihydro oleanolic acid represses liver fibrosis by inhibiting ERK/p38 signaling pathways.

Liver fibrosis is a common pathological process in the progression of several chronic liver diseases to cirrhosis and hepatocellular carcinoma. Therefore, the development of medications that can repress the progress of liver fibrosis is essential. We discovered that initially, 12ß-(m-methyl-benzoyl)-11,12-dihydro oleanolic acid (12d-OA), a farnesoid X receptor (FXR) modulator, possessed potential anti-fibrotic properties. Through an in-depth study, we revealed that 12d-OA not only inhibited the expression of fibrogenic markers in the LX-2 cells and HSC-T6 cells but also exhibited significant protective effects against liver injury and liver fibrosis in bile duct ligation (BDL) rats. Further exploration of its molecular mechanism indicated that 12d-OA exerted antifibrotic activity by inhibiting the extracellular signal-regulated kinase (ERK)/stress-activated protein kinase (p38) signaling pathways. Consequently, the great effects of 12d-OA in vitro and in vivo suggest that it may be a good candidate for liver fibrosis.

Quinic Acid Alleviates Behavior Impairment by Reducing Neuroinflammation and MAPK Activation in LPS-Treated Mice.

Compared to other organs, the brain has limited antioxidant defenses. In particular, the hippocampus is the central region for learning and memory and is highly susceptible to oxidative stress. Glial cells are the most abundant cells in the brain, and sustained glial cell activation is critical to the neuroinflammation that aggravates neuropathology and neurotoxicity. Therefore, regulating glial cell activation is a promising neurotherapeutic treatment. Quinic acid and its derivatives possess anti-oxidant and anti-inflammatory properties. Although previous studies have evidenced quinic acid's benefit on the brain, in vivo and in vitro analyses of its anti-oxidant and anti-inflammatory properties in glial cells have yet to be established. This study investigated quinic acid's rescue effect in lipopolysaccharide (LPS)-induced behavior impairment. Orally administering quinic acid restored social impairment and LPS-induced spatial and fear memory. In addition, quinic acid inhibited proinflammatory mediator, oxidative stress marker, and mitogen-activated protein kinase (MAPK) activation in the LPS-injected hippocampus. Quinic acid inhibited nitrite release and extracellular signal-regulated kinase (ERK) phosphorylation in LPS-stimulated astrocytes. Collectively, quinic acid restored impaired neuroinflammation-induced behavior by regulating proinflammatory mediator and ERK activation in astrocytes, demonstrating its potential as a therapeutic agent for neuroinflammation-induced brain disease treatments.

Activation of ASIC3/ERK pathway by paeoniflorin improves intestinal fluid metabolism and visceral sensitivity in slow transit constipated rats.

Slow transit constipation (STC) is one of the most common gastrointestinal disorders in children and adults worldwide. Paeoniflorin (PF), a monoterpene glycoside compound extracted from the dried root of Paeonia lactiflora, has been found to alleviate STC, but the mechanisms of its effect remain unclear. The present study aimed to investigate the effects and mechanisms of PF on intestinal fluid metabolism and visceral sensitization in rats with compound diphenoxylate-induced STC. Based on the evaluation of the laxative effect, the abdominal withdrawal reflex test, enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry were used to detect the visceral sensitivity, fluid metabolism-related proteins, and acid-sensitive ion channel 3/extracellular signal-regulated kinase (ASIC3/ERK) pathway-related molecules. PF treatment not only attenuated compound diphenoxylate-induced constipation symptoms and colonic pathological damage in rats but also ameliorated colonic fluid metabolic disorders and visceral sensitization abnormalities, as manifested by increased colonic goblet cell counts and mucin2 protein expression, decreased aquaporin3 protein expression, improved abdominal withdrawal reflex scores, reduced visceral pain threshold, upregulated serum 5-hydroxytryptamine, and downregulated vasoactive intestinal peptide levels. Furthermore, PF activated the colonic ASIC3/ERK pathway in STC rats, and ASIC3 inhibition partially counteracted PF's modulatory effects on intestinal fluid and visceral sensation. In conclusion, PF alleviated impaired intestinal fluid metabolism and abnormal visceral sensitization in STC rats and thus relieved their symptoms through activation of the ASIC3/ERK pathway.

Exploring the secrets of virus entry: the first respiratory syncytial virus carrying beta lactamase.

Background: Respiratory Syncytial Virus (RSV) presents a significant health threat, especially to young children. In-depth understanding of RSV entry mechanisms is essential for effective antiviral development. This study introduces an innovative RSV variant, featuring the fusion of the beta-lactamase (BlaM) enzyme with the RSV-P phosphoprotein, providing a versatile tool for dissecting viral entry dynamics. Methods: Using the AlphaFold2 algorithm, we modeled the tertiary structure of the P-BlaM chimera, revealing structural similarities with both RSV-P and BlaM. Functional assessments, utilizing flow cytometry, quantified beta-lactamase activity and GFP expression in infected bronchial epithelial cells. Western blot analysis confirmed the integrity of P-BlaM within virions. Results: The modeled P-BlaM chimera exhibited structural parallels with RSV-P and BlaM. Functional assays demonstrated robust beta-lactamase activity in recombinant virions, confirming successful P-BlaM incorporation as a structural protein. Quercetin, known for its antiviral properties, impeded viral entry by affecting virion fusion. Additionally, Ulixertinib, an ERK-1/2 inhibitor, significantly curtailed viral entry, implicating ERK-1/2 pathway signaling. Conclusions: Our engineered RSV-P-BlaM chimera emerges as a valuable tool, illuminating RSV entry mechanisms. Structural and functional analyses unveil potential therapeutic targets. Quercetin and Ulixertinib, identified as distinct stage inhibitors, show promise for targeted antiviral strategies. Time-of-addition assays pinpoint quercetin's specific interference stage, advancing our comprehension of RSV entry and guiding future antiviral developments.

Role of plant homeodomain finger protein 8 in P19 embryonic carcinoma cells revealed by genome editing and specific inhibitor.

Plant homeodomain finger protein 8 (PHF8) is a histone demethylase that regulates the expression of various genes. PHF8 targets repressor histone markers and activates gene expression. Although PHF8 has been involved in X-linked mental retardation and certain types of cancers, the role of PHF8 remains largely unknown, and its relevance to the pathogenesis of these diseases is also uncertain. In the present study, we aimed to clarify the cellular function of PHF8 in P19 cells using Phf8 knockout (KO) cells generated via the CRISPR-Cas9 system and by performing PHF8 specific inhibitor experiments, instead of using PHF8 small interfering RNA transfection. After establishing Phf8 KO cells, we analyzed the effects of PHF8 on neuronal differentiation and cell proliferation. Both PHF8 deficiency and inhibition of its activity did not considerably affect neuronal differentiation, however, they showed an increased trend of promoted neurite outgrowth. Moreover, we found that PHF8 regulated cell proliferation via the MEK/ERK pathway. PHF8 deficiency and activity inhibition reduced the phosphorylation of ERK and MEK. The MEK expression level was associated with PHF8 expression, as revealed by chromatin immunoprecipitation analysis. These results suggested that PHF8 regulates cell proliferation via the MEK/ERK pathway in P19 embryonic carcinoma cells.

Potential Therapeutic Effects of Bifidobacterium breve MCC1274 on Alzheimer's Disease Pathologies in AppNL-G-F Mice.

We previously demonstrated that orally supplemented Bifidobacterium breve MCC1274 (B. breve MCC1274) mitigated Alzheimer's disease (AD) pathologies in both 7-month-old AppNL-G-F mice and wild-type mice; thus, B. breve MCC1274 supplementation might potentially prevent the progression of AD. However, the possibility of using this probiotic as a treatment for AD remains unclear. Thus, we investigated the potential therapeutic effects of this probiotic on AD using 17-month-old AppNL-G-F mice with memory deficits and amyloid beta saturation in the brain. B. breve MCC1274 supplementation ameliorated memory impairment via an amyloid-cascade-independent pathway. It reduced hippocampal and cortical levels of phosphorylated extracellular signal-regulated kinase and c-Jun N-terminal kinase as well as heat shock protein 90, which might have suppressed tau hyperphosphorylation and chronic stress. Moreover, B. breve MCC1274 supplementation increased hippocampal synaptic protein levels and upregulated neuronal activity. Thus, B. breve MCC1274 supplementation may alleviate cognitive dysfunction by reducing chronic stress and tau hyperphosphorylation, thereby enhancing both synaptic density and neuronal activity in 17-month-old AppNL-G-F mice. Overall, this study suggests that B. breve MCC1274 has anti-AD effects and can be used as a potential treatment for AD.