P65 Expression Research Articles

Integrating network pharmacology and experimental verification to study the mechanism of Polygonum hydropiper total flavonoids against stress-induced gastric mucosal damage

ContextPolygonum hydropiper L. (P. hydropiper) has outstanding clinical efficacy in treating both acute and chronic gastroenteritis. However, the definite mechanism remains unclear. ObjectiveThis study aimed to explore the potential mechanisms of the total flavonoid of P. hydropiper (FPH) in stress-induced gastric mucosal damage (SGMD) rats through a combination of network pharmacology, molecular docking, and animal experiments. MethodsNetwork pharmacology and molecular docking were utilized to predict the potential mechanisms of FPH against SGMD. In experimental studies, SGMD rat models were established using water-immersion restraint stress (WIRS). FPH was administered at doses of 140, 70, and 35 mg/kg, with ranitidine serving as a positive control, through gavage once daily for 6 consecutive days after model establishment. Stomach and serum specimens were analyzed using HE staining, Western blotting, qPCR, and ELISA to investigate the protective mechanism of FPH in SGMD. ResultsThe network pharmacology analysis identified 16 active ingredients and 183 common targets, with potential pathways including PI3K/Akt, MAPK and Keap1/Nrf2. In vivo experiments demonstrated that FPH intervention alleviated SGMD pathological changes, reduced elevated serum IL-6 and TNF-α levels, and enhanced SOD and GSH activity in rats. Additionally, FPH increased the protein expression of p62, Nrf2, HO-1, PI3K, and p-Akt, along with mRNA levels of Nrf2, p62, and HO-1. ConclusionsFPH exerts a gastric mucosal protective effect by upregulating antioxidant gene expression through the PI3K/Akt and Keap1/Nrf2 pathways. This study provides an experimental basis for the potential clinical treatment of SGMD with the traditional Chinese medicine P. hydropiper.

Dipsacoside B Attenuates Atherosclerosis by Promoting Autophagy to Inhibit Macrophage Lipid Accumulation.

Atherosclerosis is a chronic inflammatory disease characterized by lipid accumulation and foam cell formation in the arterial wall. Promoting macrophage autophagy has emerged as a promising therapeutic strategy against atherosclerosis. Dipsacoside B (DB) is an oleanane-type pentacyclic triterpenoid saponin extracted from Lonicerae flos with potential anti-atherosclerotic properties. In this study, we investigated the effects of DB on atherosclerosis progression in ApoE-/- mice fed a high-fat diet and explored the underlying mechanisms in oxidized low-density lipoprotein (ox-LDL)-induced foam cells. DB treatment significantly reduced atherosclerotic lesion size, improved plaque stability, and regulated lipid metabolism without impairing liver and kidney function in ApoE-/- mice. In vitro studies revealed that DB dose-dependently inhibited ox-LDL internalization and intracellular lipid accumulation in RAW264.7 macrophages. Mechanistically, DB induced autophagy, as evidenced by increased autophagosome formation and upregulated expression of autophagy markers LC3-II and p62 both in vivo and in vitro. Inhibition of autophagy by chloroquine abolished the antiatherosclerotic and pro-autophagic effects of DB. Furthermore, DB treatment increased LC3-II and p62 mRNA levels, suggesting transcriptional regulation of autophagy. Collectively, our findings demonstrate that DB exerts anti-atherosclerotic effects by inhibiting foam cell formation via autophagy induction, providing new insights into the pharmacological actions of DB and its potential as a therapeutic agent against atherosclerosis.

METTL3-mediated m6A modification of SIRT1 mRNA affects the progression of diabetic cataracts through cellular autophagy and senescence

BackgroundThe increasing incidence of diabetes mellitus has established diabetic cataracts (DC) as a significant worldwide public health issue. The mechanisms underlying DC remain unknown, and effective prevention and treatment strategies are lacking. Accordingly, we aimed to explore the role and mechanism behind N6-methyladenosine (m6A) in DC progression.MethodsMethyltransferase-like 3 (METTL3), p21, Beclin1, LC3, and p62 expression levels were measured in human tissues. This study assessed total m6A levels and common m6A-regulated biomarkers in both in vitro and in vivo DC models. Autophagy flux was detected in vitro through Ad-mCherry-GFP-LC3B and Monodansylcadaverine (MDC) staining. Cellular senescence was assessed utilizing the senescence-associated β-galactosidase (SA-β-Gal) assay. Furthermore, the effect of METTL3 on SIRT1 mRNA modification was demonstrated, and its mechanism was elucidated using RT-qPCR, western blot, RNA stability assays, and RIP analysis.ResultsMETTL3, p21, and p62 expression levels were elevated in lens epithelial cells (LECs) from DC patients, while Beclin1 and LC3 levels were reduced. Silencing METTL3-mediated m6A modifications restored high-glucose-induced autophagy inhibition and prevented premature senescence in LECs. Notably, SIRT1720 and Metformin significantly enhanced autophagosome generation and delayed cellular senescence. The m6A-reading protein YTHDF2 bound to m6A modifications, and YTHDF2 silencing significantly reduced METTL3-mediated SIRT1 inactivation.ConclusionsMETTL3 induces senescence in DC by destabilizing SIRT1 mRNA in an m6A-YTHDF2-dependent manner. The METTL3-YTHDF2-SIRT1 axis is a key target and potential pathogenic mechanism in DC.

C-Jun N-terminal Kinase Supports Autophagy in Testicular Ischemia but Triggers Apoptosis in Ischemia-Reperfusion Injury.

Oxidative stress triggered by testicular torsion and detorsion in young males could negatively impact future fertility. Using a rat animal model for testicular IRI (tIRI), we aim to study the induction of autophagy (ATG) during testicular ischemia and tIRI and the role of oxidative-stress-induced c-Jun N-terminal Kinase (JNK) as a cytoprotective mechanism. Sixty male Sprague-Dawley rats were divided into five groups: sham, ischemia only, ischemia+SP600125 (a JNK inhibitor), tIRI only, and tIRI+SP600125. The tIRI rats underwent an ischemic injury for 1 h followed by 4 h of reperfusion, while ischemic rats were subjected to 1 h of ischemia only without reperfusion. Testicular-ischemia-induced Beclin 1 and LC3B expression was associated with decreased p62/SQSTM1 expression, increased ATP and alkaline phosphatase (AP) activity, and slightly impaired spermatogenesis. SP600125 treatment improved p62 expression and reduced the levels of Beclin 1 and LC3B but did not affect ATP or AP levels. The tIRI-induced apoptosis lowered the expression of the three ATG proteins and AP activity, activated caspase 3, and caused spermatogenic arrest. SP600125-inhibited JNK during tIRI restored sham levels to all investigated parameters. This study emphasizes the regulatory role of JNK in balancing autophagy and apoptosis during testicular oxidative injuries.

Galectin-9 activates host immune response and improve immunoprotection of Onychostoma macrolepis against Aeromonas hydrophila infection

Galectin-9 (Gal-9) belongs to a family of the glycan-binding proteins (GBPs) and is known to restrict bacterial activity via interacting with pathogen associated molecular pattern (PAMPs). However, the underlying immune mechanism of endogenous Gal-9 on fish against bacterial infection is still unclear. In this study, effect of Gal-9 from Onychostoma macrolepis (OmGal-9) on expression of immune related-genes were measured by HEK293T. The immune response of O. macrolepis with OmGal-9 overexpression to Aeromonas hydrophila (A. hydrophila) infection (1.65×108 CFU/mL) were evaluated by tissue bacterial load, fish survival rate and transcriptome analysis. The results showed that OmGal-9 displayed a punctate distribution in the nucleus and cytoplasm of HEK293T cells. Compared to cells transfected with the empty vector (EV) group, recombinant plasmid pEGFP-Gal9 treatment (Gal9) significantly down-regulated the expression of immune-related genes TNFα, STAT3, MyD88, LCK, and p52 of HEK293T cells stimulated with LPS at 24 h, while up-regulated IκBα and caspase1 (P < 0.05). The activities of catalase (CAT), superoxide dismutase (SOD), the total antioxidant capacity (T-AOC), alkaline phosphatase (AKP), acid phosphatase (ACP), and lysozyme (LZM) of O.macrolepis were significantly increased on 7 days in Gal9 group compared to EV group (P < 0.05). The bacterial load of liver, spleen, and kidney of O.macrolepis infected with A. hydrophila in Gal9 group at 24 h significantly lower than that in EV group (P < 0.05), and the survival rate has increased from 15% to 35%. A comparative transcriptome analysis between the Gal9 and EV group identified 305 differentially expressed genes (DEGs). The analysis showed that OmGal-9 might play important regulatory in glycolysis / gluconeogenesis, fatty acid degradation, and ascorbate and aldarate metabolism. Moreover, the immune-related DEGs were predominantly enriched in eleven pathways, with the most important three of them being linked to innate immunity: NOD-like, C-type lectin and Toll-like receptor signaling pathway. Taking together, OmGal-9 can enhance the resistance of fish to bacterial diseases by improving immune system function and activating immune-related pathways.

Supplementing ageing male laying breeders with lycopene alleviates oxidative stress in testis and improves testosterone secretion

BackgroundReproductive performance is a crucial aspect of poultry production and is carefully controlled by endocrine, paracrine, and autocrine factors. This study aimed to investigate the effect of lycopene on testosterone synthesis in Leydig cells of laying breeder roosters, clarify the mechanism of lycopene improving Leydig cells function and promoting testosterone production, and explore the role of related signal transduction pathways in testosterone synthesis. ResultsA total of 96 healthy 55-week-old breeding roosters were randomly assigned to one of five dietary treatments. They were provided with a corn-soybean meal-based diet containing different levels of lycopene: 0 mg/kg (control), 50 mg/kg, 100 mg/kg, or 200 mg/kg. The experiment lasted for 6 weeks. With the increase in lycopene levels, the testosterone content in the plasma was significantly higher than in the control group. Testicular Leydig cells were isolated and cultured from fresh testicular tissue of 45-wk-old to 60-wk-old breeding roosters. Various doses of lycopene were administered to Leydig cells, and subsequently, cells were collected for the detection of cell viability and testosterone content. The optimal concentration of lycopene to be added was determined, and changes in mRNA expression and protein levels of key proteins involved in testosterone synthesis were investigated. The results showed that lycopene treatment significantly increased testosterone secretion, mRNA expression, and protein levels of steroid-producing enzymes. Cells were collected to measure the activity of antioxidant enzymes, the mRNA transcription level of apoptotic factors, and the protein expression of apoptotic factors after treatment with lycopene. The results showed that lycopene significantly increased the activities of antioxidant enzymes, and the ability to inhibit oxygen radicals, and decreased the content of malondialdehyde. Apoptosis was inhibited by regulating the expression of apoptosis-inducing and anti-apoptosis factors. After that, the MAPK signaling pathway and downstream SF-1, Nrf2 gene, and protein expression levels were detected. The results showed that lycopene treatment significantly increased the gene and protein expression of JNK, SF-1, and Nrf2, and significantly decreased the gene and protein expression of p38. ConclusionsLycopene treatment could promote testosterone synthesis of testicular Leydig cells by activating MAPK-SF-1 (increasing steroid-producing enzyme level) and MAPK-Nrf2 pathways (resisting oxidative damage).

Thymoquinone Effects on the Expression of p62 Gene in Cisplatin-Induced Testicular Damage in Mice

Background: Cisplatin (CPN) is widely used for the management of various malignant tumors. Objectives: This study investigated the effects of Thymoquinone (TQN) on the expression of the p62 gene in CPN-induced testicular damage in mice. Methods: Histomorphometry, testis injury scores, expression of p62, and protein levels of LC3-II were assessed. Results: Cisplatin induced histological changes, increased p62 expression (P &lt; 0.01), and reduced LC3-II levels (P &lt; 0.001). Thymoquinone pretreatment decreased p62 expression while increasing LC3-II protein levels. Thymoquinone significantly reversed the testicular injury scores and improved histomorphometric parameters. Conclusions: The results indicate that TQN enhances autophagy and improves testicular tissue in CPN-intoxicated mice.

Sacubitril/valsartan attenuated myocardial inflammation, fibrosis, apoptosis and promoted autophagy in doxorubicin-induced cardiotoxicity mice via regulating the AMPKα-mTORC1 signaling pathway.

This study aimed to investigate the potential cardioprotective effects of sacubitril/valsartan (Sac/Val) in mice with doxorubicin (DOX)-induced cardiomyopathy, a common manifestation of cancer therapy-related cardiac dysfunction (CTRCD) associated with DOX. A total of thirty-two mice were equally classified into 4 groups: control group, DOX (total 24mg/kg), Sac/Val (80mg/kg), and Sac/Val + DOX (Sac/Val was given from seven days before doxorubicin administration). Neonatal rat ventricular myocytes was exposed to 5µM of DOX for 6h in vitro to mimic the in vivo conditions. A variety of techniques were used to investigate cardiac inflammation, fibrosis, apoptosis, and autophagy, including western blot, real-time quantitative PCR (RT-qPCR), immunohistochemistry, and fluorescence. Mice with DOX-induced cardiotoxicity displayed impaired systolic and diastolic function, characterized by elevated levels of cardiac inflammation, fibrosis, cardiomyocyte hypertrophy, apoptosis, and autophagy inhibition in the heart. Treatment with Sac/Val partially reversed these effects. In comparison to the control group, the protein expression of NLRP3, caspase-1, collagen I, Bax, cleaved caspase-3, and P62 were significantly increased, while the protein expression of Bcl-2 and LC3-II were significantly decreased in the myocardial tissues of the Dox-induced cardiomyopathy group. The administration of Sac/Val demonstrated the potential to partially reverse alterations in protein expression within the myocardium of mice with DOX-induced cardiotoxicity by modulating the AMPKα-mTORC1 signaling pathway and suppressing oxidative stress. Additionally, Sac/Val treatment may mitigate Dox-induced apoptosis and inhibition of autophagy in primary cardiomyocytes. Sac/Val seems to be cardioprotective against DOX-induced cardiotoxicity in the pre-treatment mice model. These findings could be attributed to the anti-inflammatory, antioxidant, anti-apoptotic, and de-autophagy effects of Sac/Val through regulation of the AMPKα-mTORC1 signaling pathway.

Effects of an Extract of Physalis Peruviana Linnaeus on the Expression of Inflammatory Markers in the Caco-2 Intestinal Epithelium-like Cell Line

Objective: Physalis Peruviana Linnaeus (PPL) is an herbaceous species characterized by a wide variety of bioactive compounds to which anti-inflammatory properties have been attributed. This makes this fruit a possible complementary therapy for diseases that involve chronic inflammation, such as inflammatory bowel diseases (IBD). In the present study, the effect of a PPL extract on the expression of inflammatory markers in the Caco-2 cell line was evaluated. Methods: An in vitro gastric digest (50 g PPL pulp) was performed, obtaining an extract that was used to challenge Caco-2 cells for 24 and 72 hours. This extract was characterized by LC-MS/MS. Then, the relative mRNA expression of NF-kB, TLR4, IL-18 and MCP-1 was determined through qRT-PCR and the protein levels of TNF-α, IL-6, IL-8, IL-18 and MCP-1 through Luminex Immunoassay. Results: From the characterization of the extract, compounds with bioactive potential such as isothiocyanates, indoles and coumarins were found. Treatment of Caco-2 cells with PPL extract (80 µg/ml), particularly for 72 hours, produced a reduction of IL-18 and MCP-1 mRNA expression (p < 0.01), in addition to IL-18 (p < 0.01), IL-8 (p < 0.0001) and MCP-1 (p < 0.01) protein levels, however, no effects on NF-kB p65 (p = 0.09) and TLR4 (p = 0.20) mRNA expression were observed. Conclusion: The results obtained in this study open the possibility that the regular consumption of 50 g of PPL could constitute a possible complementary therapy for the treatment of IBD, improving the quality of life of these patients.

Dynamic changes in Beclin-1, LC3B, and p62 in aldose reductase-knockout mice at different time points after ischemic stroke

Ischemic stroke is a brain injury caused by cerebral blood circulation disorders and is closely related to oxidative stress. Aldose reductase (AR) is a critical enzyme involved in oxidative stress. Autophagy has previously been found to play a key role in cerebral ischemia‒reperfusion injury. However, it is still unclear how autophagy molecules change after cerebral ischemia‒reperfusion injury in AR knockout mice (AR−/−). A transient middle cerebral artery occlusion (tMCAO) model was generated in AR−/− mice, and the neurological deficit scores of the mice were observed and recorded on Days 1, 3 and 5 after tMCAO. Neuronal damage in the ischemic penumbra was observed by TTC, HE, and Nissl staining. The expression of the autophagy-related molecules Beclin-1, LC3II/I, and P62 as well as that of molecules related to inflammation, oxidative stress, and neurological damage was detected by RT‒qPCR, western blotting, and immunofluorescence. Autophagosomes were observed using a transmission electron microscope. Cerebral ischemia‒reperfusion injury caused neurological deficits and ischemic infarction in tMCAO mice (P < 0.01). Beclin-1, Bcl2/Bax, SOD, GSH-px, P62, PSD95, and TOM20 levels decreased (P < 0.05), while IL-6, LC3II/I, and GFAP levels increased (P < 0.01) in the AR−/− tMCAO-1d group and the AR−/− tMCAO-3d group, compared to those in the sham group. Beclin-1, Bcl2/Bax, NOX4, GSH-px, P62, and PSD95 levels increased (P < 0.01), while IL-6, LC3II/I, and GFAP levels decreased (P < 0.01) in the AR−/− tMCAO-5d group compared to those in the AR−/− tMCAO-1d group. Autophagosome formation was observed in tMCAO mice. In summary, the changes in autophagy proteins in the brain tissue of the AR−/− mice after tMCAO were more obvious on Days 1 and 3 after tMCAO. The expression of Beclin-1 and P62 decreased, and the expression of LC3B increased after cerebral ischemia‒reperfusion injury in AR−/− mouse brain tissue.

NF-κB p105-mediated nuclear translocation of ERK is required for full activation of IFNγ-induced iNOS expression

Inducible nitric oxidase (iNOS) encoded by Nos2 is a representative IFNγ-inducible effector molecule that plays an important role in both innate and adaptive immunity. In the present study, we demonstrated that full-length NF-κB p105 (p105), which is a precursor of NF-κB p50 (p50), is required for full activation of IFNγ-induced iNOS expression in the RAW264.7 mouse macrophage cell line. In comparison to wild-type (WT) RAW264.7 cells, p105 KO RAW264.7 (p105 KO) cells completely lost IFNγ-induced iNOS expression. Despite the limited effect of exogenous expression of p50 in p105 KO cells on IFNγ-induced Nos2 promoter activity, p105 expression fully restored IFNγ-induced Nos2 promoter activity to a level comparable to that of WT cells, suggesting an important role for full-length p105 in IFNγ-induced iNOS expression. While the expression and phosphorylation of JAK1 and STAT1 were rather enhanced in p105 KO cells, the phosphorylation of c-Jun downstream of MAPK signaling was decreased. IFNγ-induced phosphorylation of ERK, a kinase for IFNγ-induced c-Jun phosphorylation, was not significantly reduced in p105 KO cells, although the nuclear activity of ERK was significantly decreased due to its reduced translocation to the nucleus. Expression of iNOS, nuclear translocation of ERK, and phosphorylation of c-Jun were restored by stable supplementation of p105 in p105 KO cells. These results suggest that p105 is required for the nuclear translocation of ERK and the subsequent phosphorylation of c-Jun, which are necessary for full activation of IFNγ-induced iNOS expression. Reduced nuclear translocation of ERK in p105 KO cells was also observed in the activation of ERK following serum starvation, further suggesting that the involvement of p105 in ERK nuclear translocation is not limited to IFNγ-stimulated cells but is a more general function of p105.

Resistin alleviates lipopolysaccharide-induced inflammation in bovine alveolar macrophages by activating the AMPK/mTOR signaling pathway and autophagy

ObjectiveResistin (RETN) is an adipocyte-specific hormone that participates in metabolism and modulates cellular inflammation. Our study aimed to assess the effects of RETN treatment on autophagy and the underlying molecular and biological mechanisms in bovine alveolar macrophages (BAMs). MethodsThe optimal concentration of RETN + lipopolysaccharide (LPS) on macrophages was screened and then used to co-culture with alveolar macrophages. Autophagosomes in BAMs were examined using a transmission electron microscope (TEM). Quantitative real-time PCR (qRT-PCR) was used to detect the mRNA expression of microtubule-associated protein light chain 3 (LC3) and p62. Western blot (WB) was used to detect the protein expressions of LC3 and p62. The distribution of LC3 and p62 proteins in the cells was observed by immunofluorescence (IF). The concentrations of interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) were detected using enzyme-linked immunosorbent assay (ELISA). The protein expression of adenosine-monophosphate-activated protein kinase (AMPK), p-AMPK, mammalian target of rapamycin (mTOR), and p-mTOR was detected using WB. ResultsThe treatment of BAMs with RETN or LPS increased the number of autophagosomes and the ratio of LC3II/LC3I and decreased the expression level of p62 protein. RETN treatment significantly triggered autophagy compared to LPS treatment. Moreover, the ratios of p-AMPK/AMPK and p-mTOR/mTOR were upregulated and downregulated, respectively, after RETN treatment, suggesting that AMPK/mTOR signaling pathway activation is required for RETN-mediated autophagy in BAMs. Additionally, the ratio of LC3-II/LC3-I was lower, and the concentrations of IL-1β, IL-6, and TNF-α significantly decreased in the LPS and RETN co-treatment groups compared to the single LPS treatment group. However, both autophagy- and LPS-induced inflammation were partially alleviated by RETN treatment. ConclusionRETN can promote autophagy in BAMs by activating the AMPK/mTOR signaling pathway, it may help prevent LPS-induced inflammation.

Lanthanum chloride exerts therapeutic potential for chronic kidney disease by suppressing nanohydroxyapatite-induced mitophagy and mitochondria-mediated apoptosis

ObjectiveTo investigate the protective effect of lanthanum chloride on kidney injury in chronic kidney disease and its mechanism. Methods1. Patients with CKD stage 2–5 were selected to analyze the effect of lanthanum-containing preparations on CKD. 2. Sixty healthy male Wistar rats were randomly divided into control group, model group, lanthanum chloride groups (0.03 ng/kg, 0.1 ng/kg, 0.3 ng/kg, q.3d., i.v.), and lanthanum carbonate group (0.3 g/kg, q.d., p.o.). The model group was given 2 % adenine suspension (200 mg/kg, q.d., p.o.) for the first two weeks, followed by adenine (200 mg/kg, b.i.d., p.o.) for 2 weeks, and all animals were sacrificed after eight weeks of administration. 3. The serum and kidneys of rats in each group were collected to detect the oxidative stress indicators and the expressions of LC3B-Ⅱ/Ⅰ, p62, Bcl-2, Bax, Caspase-3 and Cleaved Caspase-3. 4. Human renal tubular epithelial cells (HK-2 cells) were divided into control group, model group, lanthanum chloride group, pyrophosphate (PPI) group, chloroquine (CQ) group, rapamycin group, doxorubicin (DOX) group and N-acetyl-L-cysteine (NAC) group. The mitochondrial status, mitophagy and apoptosis levels were detected. Results1.Lanthanum-containing preparations can significantly reduce the biochemical indexes of kidney injury in patients with CKD. 2. In the model group, the glomerular and renal tubular edema, the mitochondria were short and round, and the expression of LC3B-Ⅱ/Ⅰ and Bax increased, while the expression of P62, Bcl-2 and Caspase-3 decreased, and there was a significant improvement in the administration group, especially the 0.1 ng/kg group and lanthanum carbonate group. 3. In the HK-2 cell model group, mitochondrial membrane potential decreased, morphology changed and the results were reversed by lanthanum chloride. ConclusionLanthanum chloride may alter the morphology of nano-hydroxyapatite, thereby inhibiting its induced mitophagy and mitochondria-mediated apoptosis, and ultimately improve CKD renal injury effectively.

Fermented Fish Collagen Attenuates Melanogenesis via Decreasing UV-Induced Oxidative Stress.

Excessive melanogenesis leads to hyperpigmentation-related cosmetic problems. UV exposure increases oxidative stress, which promotes melanogenesis-related signal pathways such as the PKA, microphthalmia-associated transcription factor (MITF), tyrosinase (TYR), tyrosinase-related protein-1 (TRP1), and tyrosinase-related protein-2 (TRP2) pathways. Glycine is a source of endogenous antioxidants, including glutathione. Fermented fish collagen (FC) contains glycine; thus, we evaluated the effect of FC on decreasing melanogenesis via decreasing oxidative stress. The glycine receptor (GlyR) and glycine transporter-1 (GlyT1) levels were decreased in UV-irradiated keratinocytes; however, the expression levels of these proteins increased upon treatment with FC. The FC decreased oxidative stress, as indicated by the decreasing expression of NOX1/2/4, increased expression of GSH/GSSG, increased SOD activity, and decreased 8-OHdG expression in UV-irradiated keratinocytes. Administration of conditioned media from FC-treated keratinocytes to melanocytes led to decreased p38, PKC, MITF, TRP1, and TRP2 expression. These changes induced by the FC were also observed in UV-irradiated animal skin. FC treatment increased the expression of GlyR and GlyT, which was accompanied by decreased oxidative stress in the UV-irradiated skin. Moreover, the FC negatively regulated the melanogenesis signaling pathways, leading to decreased melanin content in the UV-irradiated skin. In conclusion, FC decreased UV-induced oxidative stress and melanogenesis in melanocytes and animal skin. FC could be used in the treatment of UV-induced hyperpigmentation problems.

Hesperetin Attenuates T-2 Toxin-Induced Chondrocyte Injury by Inhibiting the p38 MAPK Signaling Pathway.

Hesperetin, a flavonoid derived from citrus fruits, exhibits potent antioxidant and anti-inflammatory activities and has been implicated in cartilage protection. However, its effectiveness against T-2 toxin-induced knee cartilage damage remains unclear. In this study, high-throughput sequencing analysis was employed to identify the key signaling pathways involved in T-2 toxin-induced articular cartilage damage in rats. Animal models were divided into the following groups: control, low-dose T-2 toxin, high-dose T-2 toxin, T-2 toxin + hesperetin, hesperetin, and vehicle. Pathological staining and immunohistochemistry were used to assess pathological changes, as well as the expression levels of the cartilage matrix-related proteins MMP13 and collagen II, along with the activation of the p38 MAPK signaling pathway. Additionally, primary rat chondrocytes were cultured to establish an in vitro model for investigating the underlying mechanism. High-throughput sequencing analysis revealed the involvement of the MAPK signaling pathway in T-2 toxin-induced articular cartilage damage in rats. Hesperetin intervention in T-2 toxin-exposed rats attenuated pathological cartilage damage. Immunohistochemistry results demonstrated a significant reduction in collagen II protein expression in the high-dose T-2 toxin group (p < 0.01), accompanied by a significant increase in MMP13 protein expression (p < 0.01). In both the articular cartilage and the epiphyseal plate, the T-2 toxin + hesperetin group exhibited significantly higher collagen II protein expression than the high-dose T-2 toxin group (p < 0.05), along with significantly lower MMP13 protein expression (p < 0.05). Hesperetin inhibited the over-activation of the p38/MEF2C signaling axis induced by T-2 toxin in primary rat chondrocytes. Compared to the T-2 toxin group, the T-2 toxin + hesperetin group showed significantly reduced phosphorylation levels of p38 and protein expression levels of MEF2C (p < 0.001 or p < 0.05). Moreover, the T-2 toxin + hesperetin group exhibited a significant decrease in MMP13 protein expression (p < 0.05) and a significant increase in collagen II protein expression (p < 0.01) compared to the T-2 toxin group. T-2 toxin activates the p38 MAPK signaling pathway, causing knee cartilage damage in rats. Treatment with hesperetin inhibits the p38/MEF2C signaling axis, regulates collagen II and MMP13 protein expression, and reduces cartilage injury significantly.

Vangl2 suppresses NF-κB signaling and ameliorates sepsis by targeting p65 for NDP52-mediated autophagic degradation.

Van Gogh-like 2 (Vangl2), a core planar cell polarity component, plays an important role in polarized cellular and tissue morphology induction, growth development, and cancer. However, its role in regulating inflammatory responses remains elusive. Here, we report that Vangl2 is upregulated in patients with sepsis and identify Vangl2 as a negative regulator of The nuclear factor-kappaB (NF-κB) signaling by regulating the protein stability and activation of the core transcription component p65. Mice with myeloid-specific deletion of Vangl2 (Vangl2ΔM) are hypersusceptible to lipopolysaccharide (LPS)-induced septic shock. Vangl2-deficient myeloid cells exhibit enhanced phosphorylation and expression of p65, therefore, promoting the secretion of proinflammatory cytokines after LPS stimulation. Mechanistically, NF-κB signaling-induced-Vangl2 recruits E3 ubiquitin ligase PDLIM2 to catalyze K63-linked ubiquitination on p65, which serves as a recognition signal for cargo receptor NDP52-mediated selective autophagic degradation. Taken together, these findings demonstrate Vangl2 as a suppressor of NF-κB-mediated inflammation and provide insights into the crosstalk between autophagy and inflammatory diseases.

The Cytidine N-Acetyltransferase NAT10 Promotes Thalamus Hemorrhage-Induced Central Poststroke Pain by Stabilizing Fn14 Expression in Thalamic Neurons.

The recognition of RNA N4-acetylcytidine (ac4C) modification as a significant type of gene regulation is growing; nevertheless, whether ac4C modification or the N-acetyltransferase 10 protein (NAT10, the only ac4C "writer" that is presently known) participates in thalamus hemorrhage (TH)-induced central poststroke pain (CPSP) is unknown. Here, we observed NAT10 was primarily located in the neuronal nuclei of the thalamus of mice, with Fn14 and p65. An increase of NAT10 mRNA and protein expression levels in the ipsilateral thalamus was observed from days 1 to 14 after TH. Inhibition of NAT10 by several different approaches attenuated Fn14 and p65 upregulation of TH mice, as well as tissue injury in the thalamus on the ipsilateral side, and the development and maintenance of contralateral nociceptive hypersensitivities. NAT10 overexpression increased Fn14 and p65 expression and elicited nociceptive hypersensitivities in naïve mice. Our findings suggest that ac4C modification and NAT10 participate in TH-induced CPSP by activating the NF-κB pathway through upregulating Fn14 in thalamic neurons. NAT10 could serve as a promising new target for CPSP treatment.

Clinicopathologic Analysis of HPV-Related Primary Squamous Cell Carcinoma of the Thyroid.

This study aims to explore the clinical and pathologic characteristics of HPV-related primary thyroid squamous cell carcinoma (PSCCT), a rare tumor classified by WHO-5 as a subtype of anaplastic thyroid carcinoma (ATC). Clinical data, histomorphology, immunohistochemistry, HPV detection, and B-raf gene point mutations of 3 PSCCT cases were analyzed. Subsequent follow-up was conducted post-treatment. All 3 cases involved female patients aged between 60 and 76. Microscopic examination revealed squamous cell carcinoma in cases 1 and 3, whereas case 2 exhibited both squamous cell carcinoma and papillary thyroid carcinoma components. Immunohistochemistry demonstrated CK19, PAX8, and TTF1 expression in the papillary thyroid carcinoma component, and CK5/6, p63, p40, and PAX8 expression in the squamous cell carcinoma component. P16 exhibited diffuse positivity in both squamous cell carcinoma and classic papillary carcinoma. HPV analysis identified low-risk type 6 positivity in cases 1 and 3, while both squamous cell carcinoma and papillary carcinoma areas in case 2 were positive for HPV-33. B-raf gene mutation was exclusive to case 2. Diagnosis of PSCCT necessitates multidisciplinary assessment, incorporating clinical symptoms, imaging, histomorphology, and immunohistochemistry. This study, for the first time, reveals the presence of HPV DNA in both PTC and PSCCT, occurring concurrently but separately. Given the limited scope of 3 case reports, definitive conclusions cannot be drawn, warranting further investigation.

Cylindromatosis lysine 63 deubiquitinase (CYLD) suppress TLR3-mediated CCL5 expression in human renal proximal tubular epithelial cells.

One of the causes of tubulointerstitial nephritis is viral infection, with innate immune responses affecting its pathogenesis. Toll-like receptor 3 (TLR3) recognizes viral infections and acts antivirally by activating signaling to produce inflammatory cytokines/chemokines, including C-C motif chemokine ligand 5 (CCL5) and interferon-β (IFN-β). Although cylindromatosis lysine 63 deubiquitinase (CYLD) is known to be associated with tubulointerstitial nephritis and renal function, its role in the antiviral innate immune response in tubular epithelial cells remains unknown. In this study, we investigated the association between CYLD and TLR3-mediated CCL5 production in cultured human renal proximal tubular epithelial cells (hRPTECs). Polyinosinic-polycytidylic acid (poly IC), a synthetic TLR3 ligand, was used to stimulate hRPTECs. mRNA expression was measured using reverse transcription-quantitative polymerase chain reaction. Protein expression was assayed using western blotting or an enzyme-linked immunosorbent assay. Knockdown of IFN-β, nuclear factor-kappa B (NF-κB) p65, and CYLD was performed by transfecting cells with specific small interfering RNAs. The intracellular localization of CYLD in hRPTECs was analyzed using immunofluorescence. Poly IC induced CCL5 expression in a time- and concentration-dependent manner, and knockdown of either IFN-β or p65 reduced poly IC-induced CCL5 expression. CYLD knockdown increased the poly IC-induced CCL5, phosphorylated IκB kinase α/β (IKK complex), and phosphorylated p65 expression. The CYLD protein was localized in the cytoplasm, and poly IC did not alter its expression. CYLD may prevent excessive inflammation due to an antiviral innate immune response by suppressing IKK complex and NF-κB activation downstream of TLR3 in hRPTECs.

Melatonin mitigates matrix stiffness-induced intervertebral disk degeneration by inhibiting reactive oxygen species and melatonin receptors mediated PI3K/AKT/NF-κB pathway.

Intervertebral disk degeneration (IVDD) may lead to an increase in extracellular matrix (ECM) stiffness, potentially contributing to the progression of the disease. Melatonin reportedly mitigates IVDD; however, its potential to attenuate elevated matrix stiffness-induced IVDD remains unexplored. Therefore, we aimed to investigate whether melatonin can alleviate the progression of IVDD triggered by increased matrix stiffness and elucidate its underlying mechanisms. Nucleus pulposus (NP) tissues were collected from patients, and ECM stiffness, reactive oxygen species (ROS) levels, apoptosis rates, and P65 expression in these tissues with varying Pfirrmann scores were determined. In vitro experiments were conducted to investigate the effects of melatonin on various pathophysiological mechanisms within the NP cells cultured on soft substrates with differing stiffness levels. Our findings revealed a positive correlation between ECM stiffness in human NP tissue and degree of IVDD. In addition, phosphorylation of P65 exhibited a strong association with matrix stiffness. Enhanced levels of ROS and cellular apoptosis were observed within degenerated intervertebral disks. In vitro experiments demonstrated that melatonin significantly inhibited catabolism and apoptosis induced by stiff matrices, along with elevated ROS levels. Furthermore, we observed that melatonin inhibited NP cell catabolism and apoptosis by reducing the melatonin receptors mediated activation of the PI3K/AKT and nuclear factor-kappa B (NF-κB) pathways. Also, we found that the reduction of ROS by melatonin can assist in inhibiting the activation of the NF-κB pathway. The outcomes of the in vivo experiments corroborated the results of the in vitro experiments, illustrating that melatonin treatment could alleviate the compression-induced upregulation of matrix stiffness in NP and IVDD. Collectively, melatonin can potentially alleviate high matrix stiffness-induced IVDD by reducing intracellular ROS levels and inhibiting the PI3K/AKT/NF-κB pathway.NEW & NOTEWORTHY Melatonin mitigates intervertebral disk degeneration (IVDD) induced by matrix stiffness through reactive oxygen species (ROS) reduction. Matrix stiffness is related to increased nucleus pulposus cell ROS, apoptosis, and degeneration. Melatonin inhibits PI3K/AKT/NF-κB pathways via melatonin receptors in a stiff matrix environment. In vivo, melatonin restores disk height and alleviates IVDD progression.