Mitogen-activated Protein Kinase Pathway Research Articles

Structural characterization and anti-inflammatory activities of novel polysaccharides obtained from Pleurotus eryngii

Natural polysaccharides named PEP-0.1-1, PEP-0-1 and PEP-0-2 from edible mushroom species Pleurotus eryngii were obtained in the present study. Results showed that molecular weights of these polysaccharides were 3235, 2041 and 23933 Da, respectively. Further, structural characterization revealed that PEP-0.1-1 had a →4-α-D-Glcp-1→ backbone and contained →4)-α-D-Glcp and →4)-β-D-Glcp reducing end groups. PEP-0-1 backbone contained →4-α-D-Glcp-1→ and →6-α-3-O-Me-D-Galp-1→, and the side chains contained α-D-Glcp, β-D-Manp-1→ and α-D-Glcp-3→. However, PEP-0-2 backbone consisted of →4-α-D-Glcp-1→ and →6-α-3-O-Me-D-Galp-(1→6)-α-D-Galp-1→ while the side chains contained α-D-Glcp and β-D-Manp-1→. Biological activity analysis was then carried out and found that all these polysaccharides could significantly suppress the relative mRNA expression of toll-like receptor 4, nitric oxide, tumor necrosis factor-α, interleukin (IL)-1β and IL-6 in lipopolysaccharide (LPS)-induced inflammation of RAW264.7 cells, as well as the over secretion of the above cell cytokines. Moreover, Western blotting analysis revealed that all these purified fractions displayed significant inhibition effects on the expression of c-Jun N-terminal kinases protein protein induced by LPS in mitogen activated protein kinase pathway, along with the relieving on the inhibition effect of LPS on IκB-α protein expression. In summary, the information generated by the present study could provide a theoretical basis for the exploration of novel healthy food materials from edible mushroom with anti-inflammation activities.

Regulatory T cells protect against diabetic cardiomyopathy in db/db mice.

Regulatory T cells (Tregs) have protected against many cardiovascular diseases. This study was intended to explore the effect of Tregs on diabetic cardiomyopathy (DCM) using a db/db mouse model. Eight-week-old male db/db mice were randomly divided into four groups: the control group, administered 200 μL phosphate-buffered saline; the small-dose Treg group, administered 105 Tregs; the large-dose Treg group, administered 106 Tregs; and the PC group, administered 100 μg anti-CD25 specific antibody (PC61) and 106 Tregs. After 12 weeks, mice were euthanized. Transthoracic echocardiography was carried out at the beginning and end of the experiment. Relevant basic experiments to evaluate the effects of Tregs on DCM were carried out. Echocardiography showed that the impaired diastolic and systolic functions were significantly improved in mice administered large-dose Tregs. Large-dose Tregs significantly ameliorated myocardial hypertrophy and fibrosis, and decreased hypertrophic gene expression and collagen deposition. The protective effects of Tregs on diabetic hearts were associated with decreased oxidative stress, inflammatory response and apoptosis. In addition, Tregs promoted the activation of the phosphatidylinositol 3-kinase-protein kinase B signaling pathway, whereas they inhibited extracellular signal-regulated kinase 1/2 and Jun N-terminal kinase phosphorylation, which might be responsible for the cardioprotective role of Tregs against DCM. Tregs ameliorated myocardial hypertrophy and fibrosis, improved cardiac dysfunction, and protected against DCM progression in db/db mice. The mechanisms involved a decrease of inflammatory response, oxidative stress and apoptosis, which might be mediated by phosphatidylinositol 3-kinase-protein kinase B and mitogen-activated protein kinase pathways. Hence, Tregs might serve as a promising therapeutic approach for DCM treatment.

P215 EFFECT OF OXYGEN LOADING MODEL ON RETINOPATHY OF PREMATURITY IN INTRAUTERINE GROWTH RETARDED MICE

Background and Objective: Fetal growth retardation (IUGR) not only induces various complications in newborns, but is also known to be associated with the future development of lifestyle-related diseases and conditions. Therefore, the neonatal treatment often struggles between life-sustaining and oxygen administration. We have previously reported that IUGR mice born from mothers raised on a low-protein diet show enhanced vascular remodeling. The mechanism is influenced by an increased inflammatory response associated with a decreased angiogenic response due to hypoxic loading in a femoral artery cuff implantation model. Based on this, we hypothesized that in IUGR mice, the reduced angiogenic response in retinopathy of prematurity may work to suppress the onset of the disease. To test this hypothesis, we examined the effects of oxygen loading on the retinal neovasculature using the mouse oxygen-induced retinopathy of prematurity (OIR) model. Methods The OIR model was created in newborns born from mothers raised on a normal protein diet (20%) and in IUGR newborns born from mothers raised on a low protein diet (8%). Specifically, the newborns were exposed to 75% hyperoxia for 5 days starting at 7 days of age, and retinal neovascularization was histologically evaluated 5 days later at 17 days of age for comprehensive transcriptome analysis. Results: Compared to normal birth weight OIR mice, retinal neovascularization was significantly suppressed in OIR mice with FGR. Retinal RNA sequencing revealed decreased expression of angiogenic factors that trigger pathological retinal neovascularization, such as the mitogen-activated protein kinase pathway (MAPK) pathway and corresponding upstream signaling pathways. Conclusions Our findings suggest that IUGR neonates have a weaker response to retinal oxygen stress and consequently are likely to have reduced retinopathy of prematurity. These results indicate that the risk of developing retinopathy of prematurity is attenuated in IUGR neonates compared to mature neonates with normal birth weight.

Targeting RAC1 reactivates pyroptosis to reverse paclitaxel resistance in ovarian cancer by suppressing P21-activated kinase 4.

Pyroptosis may play an important role in the resistance of ovarian cancer (OC) to chemotherapy. However, the mechanism by which pyroptosis modulation can attenuate chemotherapy resistance has not been comprehensively studied in OC. Here, we demonstrated that RAS-associated C3 botulinum toxin substrate 1 (RAC1) is highly expressed in OC and is negatively correlated with patient outcomes. Through cell function tests and in vivo tumor formation tests, we found that RAC1 can promote tumor growth by mediating paclitaxel (PTX) resistance. RAC1 can mediate OC progression by inhibiting pyroptosis, as evidenced by high-throughput automated confocal imaging, the release of lactate dehydrogenase (LDH), the expression of the inflammatory cytokines IL-1β/IL-18 and the nucleotide oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome. Mechanically, RNA-seq, gene set enrichment analysis (GSEA), coimmunoprecipitation (Co-IP), mass spectrometry (MS), and ubiquitination tests further confirmed that RAC1 inhibits caspase-1/gasdermin D (GSDMD)-mediated canonical pyroptosis through the P21-activated kinase 4 (PAK4)/mitogen-activated protein kinase (MAPK) pathway, thereby promoting PTX resistance in OC cells. Finally, the whole molecular pathway was verified by the results of in vivo drug combination tests, clinical specimen detection and the prognosis. In summary, our results suggest that the combination of RAC1 inhibitors with PTX can reverse PTX resistance by inducing pyroptosis through the PAK4/MAPK pathway.

She-Chuang-Si-Wu-Tang Alleviates Inflammation and Itching Symptoms in a Psoriasis Mouse Model by Regulating the Th17/IL-17 Axis via the STAT3/MAPK Pathways.

Psoriasis is an immune-related disorder characterized by silver scales, epidermis thickness, and itching. She-Chuang-Si-Wu-Tang (SSWT), a traditional Chinese medicine decoction, has been used clinically for 400 years. Although it benefits psoriasis treatment, the mechanism of action is still unclear. This study explores SSWT's molecular mechanism in treating psoriasis through network pharmacology analysis and experiments. We identified relevant SSWT and psoriasis targets using network pharmacology and conducted SSWT quality control with high-performance liquid chromatography (HPLC). A mouse model of psoriasis was established using imiquimod (IMQ), with the drug administered continuously for seven days, spanning an eight-day period. During the experiment, we observed spontaneous scratching behaviors and assessed the Psoriasis Area and Severity Index (PASI) scores. At the conclusion of the experiment, we examined skin tissue pathology under an optical microscope and measured epidermal thickness. Additionally, we used enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) to measure interleukin (IL)-23, IL-17A, IL-17F, and interferon (IFN)-γ levels in the mice's serum and their mRNA expression in the skin. Western blot analysis was conducted to assess protein levels related to signaling pathways. Results indicate that SSWT may target IL-17 signaling pathways and T helper (Th) 17 cell differentiation, as predicted by network pharmacology. SSWT significantly improved the PASI and Baker scores, reduced epidermal thickness, and decreased spontaneous scratching in IMQ-induced mice. Additionally, SSWT treatment significantly lowered the concentrations of inflammatory factors in the serum and skin lesions, as well as mRNA expression levels, compared to the IMQ group. Furthermore, SSWT significantly inhibited the phosphorylation of both the signal transducer and activator of transcription 3 (STAT3) and mitogen-activated protein kinase (MAPK) pathways. In summary, this study unveiled the potential anti-psoriatic mechanism of SSWT, offering new evidence for its clinical application.

Current State of Targeted Therapy in Adult Langerhans Cell Histiocytosis and Erdheim-Chester Disease.

The mitogen-activated protein kinase (MAPK) pathway is a key driver in many histiocytic disorders, including Langerhans cell histiocytosis (LCH) and Erdheim-Chester disease (ECD). This has led to successful and promising treatment with targeted therapies, including BRAF inhibitors and MEK inhibitors. Additional novel inhibitors have also demonstrated encouraging results. Nevertheless, there are several problems concerning targeted therapy that need to be addressed. These include, among others, incomplete responsiveness and the emergence of resistance to BRAF inhibition as observed in other BRAF-mutant malignancies. Drug resistance and relapse after treatment interruption remain problems with current targeted therapies. Targeted therapy does not seem to eradicate the mutated clone, leading to inevitable relapes, which is a huge challenge for the future. More fundamental research and clinical trials are needed to address these issues and to develop improved targeted therapies that can overcome resistance and achieve long-lasting remissions.

Phase II Study of Samotolisib in Children and Young Adults With Tumors Harboring Phosphoinositide 3-Kinase/Mammalian Target of Rapamycin Pathway Alterations: Pediatric MATCH APEC1621D.

Patients age 1-21 years with relapsed or refractory solid and CNS tumors were assigned to phase II studies of molecularly targeted therapies on the National Cancer Institute-Children's Oncology Group (NCI-COG) Pediatric Molecular Analysis for Therapy Choice (MATCH) trial. Patients whose tumors harbored predefined genetic alterations in the phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway and lacked mitogen-activated protein kinase pathway activating alterations were treated with the PI3K/mTOR inhibitor samotolisib. Patients received samotolisib twice daily in 28-day cycles until disease progression or unacceptable toxicity. A rolling 6 limited dose escalation was performed as, to our knowledge, this was the first pediatric study of samotolisib. The primary end point was the objective response rate; secondary end points included progression-free survival (PFS) and the recommended phase II dose and toxicity of samotolisib in children. A total of 3.4% (41/1,206) of centrally tested patients were matched to this arm. Seventeen patients were treated. Among treated patients, the most common diagnoses included osteosarcoma (n = 6) and high-grade glioma (n = 5) harboring alterations in phosphatase and tensin homolog (n = 6), PIK3CA (n = 5), and tuberous sclerosis complex 2 (n = 3). No objective responses or prolonged stable disease were observed. Three-month PFS was 12% (95% CI, 2 to 31). Two patients experienced dose-limiting toxicities (mucositis and pneumonitis). Dose level 2 (115 mg/m2/dose twice daily) was determined to be the recommended phase II dose of samotolisib in children. This nationwide study was successful at identifying patients and evaluating the efficacy of molecularly targeted therapy for rare molecular subgroups of patients in a histology-agnostic fashion. Unfortunately, there was no activity of samotolisib against tumors with PI3K/mTOR pathway alterations. Prospective trials such as the NCI-COG Pediatric MATCH are necessary to evaluate the efficacy of molecularly targeted therapies given their increasing use in clinical practice.

A Comparative Genomic Study of Conventional and Undifferentiated Melanoma

Undifferentiated melanoma, defined as melanoma that has lost all usual phenotypic and immunohistochemical characteristics of conventional melanoma, can pose significant diagnostic challenges. Molecular studies have advanced our understanding of undifferentiated melanoma by demonstrating that a subset of these tumors harbors known melanoma driver alterations in genes such as BRAF, NRAS, and NF1. However, there is a paucity of data describing genetic alterations that may distinguish undifferentiated melanoma from conventional melanoma. In this study, we directly compared the genomic profiles of undifferentiated melanoma to a cohort of conventional melanomas, including 14 undifferentiated melanoma cases (comprised of 2 primary cases, 2 cutaneous recurrences, and 10 metastases) and a cohort of 127 conventional melanomas including primary, recurrent, and metastatic cases. Targeted sequencing of 447 cancer-associated genes was performed, including identification of mutations and copy number alterations. NRAS was the most frequent melanoma driver in undifferentiated melanoma (8/14 cases, 57%), although notably, only 1 undifferentiated melanoma harbored an NRAS Q61R mutation. Compared with the conventional melanoma cohort, undifferentiated melanoma demonstrated statistically significant enrichment of pathogenic activating RAC1 mutations (6/14 total cases, 43%), including P29S (4/6 cases), P29L (1/6 cases), and D11E (1/6 cases). In addition to providing insight into the molecular pathogenesis of undifferentiated melanoma, these findings also suggest that RAS Q61R immunohistochemistry may have limited utility for its diagnosis. The presence of recurrent RAC1 mutations in undifferentiated melanoma is also to be noted as these alterations may contribute to mitogen-activated protein kinase pathway–targeted therapy resistance. Furthermore, the RAC1 alterations identified in this cohort have been shown to drive a melanocytic to mesenchymal switch in melanocytes, offering a possible explanation for the undifferentiated phenotype of these melanomas.

γ-Aminobutyric acid alleviates litchi thaumatin-like protein-induced inflammation and reduces gut microbial translocation

Previous research reported litchi thaumatin-like protein (LcTLP) could lead to inflammation, which is a factor causing the adverse reactions after excessive intake of litchi. As a main amino acid in litchi pulp, γ-aminobutyric acid (GABA) was found with anti-inflammatory effect. Therefore, this study aimed to investigate the effects of GABA on LcTLP-induced inflammation through RAW264.7 macrophages and C57BL mice models. In vitro study showed GABA could effectively regulate the level of inflammatory cytokines (interleukin (IL)-1β, IL-6, IL-10, and prostaglandin E2) and Ca2+ in cells, and inhibit the phosphorylation of p65, IκB, p38, c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK). These results indicate GABA alleviated inflammation through nuclear factor-κB and mitogen-activated protein kinase pathways signaling pathways. In vivo experiment was performed to verify the anti-inflammatory effect of GABA, and the results demonstrated that GABA reduced the inflammation and oxidative stress in the liver of LcTLP-treated mice, as it down-regulated the pro-inflammatory cytokines, malondialdehyde, aspartate transferase, and alanine transaminase. The relative expression of phosphorylated p38, JNK and ERK in mice liver with GABA treatment were reduced to 65 %, 39 % and 80 % of the control group, respectively. Furthermore, GABA treatment enriched probiotic bacteria and decreased pathogenic bacteria in mice gut, which reveals GABA could effectively reduce the translocation of gut microbiota.

Spitz melanoma

It has long been recognized that the histopathologic differential diagnosis between Spitz nevus and melanoma is sometimes extraordinarily difficult. Both can be composed of large oval to spindled melanocytes with abundant cytoplasm and large nuclei. Genomic studies over the last decade have clarified that Spitz tumors have diverse genetic initiating events, and that for each of these, there are benign, intermediate grade, and malignant lesions. Another discovery is that some melanomas can morphologically resemble Spitz tumors but have conventional initiating mutations (e.g., BRAF, NRAS). The current WHO definition of Spitz tumors restricts the spectrum to neoplasms with an activating mutation affecting the MAP kinase pathway, mostly fusions involving kinase genes. Whether splitting off Spitz tumors from other neoplasms that are only morphologically spitzoid will stand the test of time is uncertain, but for now, it does bring order to what has been a complex area. The recognition of Spitz melanoma will enable classification, follow-up, and the delineation of rational treatment guidelines for this important group of tumors, most of which are in young people. I have reviewed the logic of the WHO definition of Spitz tumors, the spectrum of tumors produced by initiating mutations, problems with the definition of Spitz melanoma, and have provided an example of this rare entity in the context of related tumors.

Downregulation of nuclear receptor-binding SET domain protein 1 induces proinflammatory cytokine expression via mitogen-activated protein kinase pathways in U87MG cells

Haploinsufficiency of the nuclear receptor binding SET domain-containing protein 1 gene (NSD1) leads to a neurodevelopmental disorder known as Sotos syndrome (SOTOS). This study investigated the effects of NSD1 knockdown in glial cells. U87MG glioma cells were transfected with siRNA targeting NSD1, which resulted in morphological changes characteristic of activated astrocytes. These activated phenotypes were accompanied by specific activation of mitogen-activated protein kinase (MAPK) signaling pathways, particularly those mediated by p38 MAPK and c-Jun N-terminal kinase (JNK). Transcriptome analysis showed increased expression of proinflammatory cytokine genes, particularly interleukin (IL)-1α, IL-1β, and IL-6, following NSD1 knockdown. Treatment with MAPK inhibitors significantly reduced the cytokine induction caused by NSD1 knockdown, with the p38 MAPK inhibitor being more effective than the JNK inhibitor. These findings provide new insights into the role of NSD1 loss in neurological dysfunctions associated with SOTOS.

AIBP promotes cell proliferation and migration through the ERK1/2-MAPK signaling pathway in hepatocellular carcinoma.

As a highly aggressive cancer, hepatocellular carcinoma (HCC) is often found at an advanced stage and has a poor prognosis. Therefore, in addition to the surgical treatment of HCC, the drug therapy for HCC is still under continuous exploration. The primary apolipoprotein of high-density lipoproteins (HDLs) is apolipoprotein A-I binding protein (AIBP), which has a significant impact on cholesterol metabolism, angiogenesis, and a wide range of inflammatory disorders, including cancer. The AIBP function in HCC is, however, yet unknown. This study aims to reveal the underlying mechanisms of AIBP influencing HCC proliferation and migration through mitogen-activated protein kinase (MAPK) pathways. AIBP expression and its clinical prognostic association were investigated using The Cancer Genome Atlas (TCGA) data. The AIBP expression was studied in human HCC tissues using immunohistochemistry (IHC) and western blotting. Colony formation assays (CFAs) and cell counting kit-8 (CCK-8) were used to determine in vitro cell proliferation. Cell migration and invasion were evaluated using wound-healing and transwell assays. A xenograft tumor model was employed to investigate HCC cell proliferation in nude mice. Tissues from HCC patients had much increased AIBP expression compared to nearby normal tissues. The prognosis for patients was bleak when AIBP expression was high. When AIBP was overexpressed in SMMC-7721 cells, the cells may become more proliferative, migrative, and invasive. In contrast, the HCC-LM3 cells' ability to proliferate, migrate, and invade was drastically decreased once AIBP was knocked down in vitro. Furthermore, in vivo research showed that AIBP overexpression may enhance cell proliferation in HCC. Finally, we discovered that AIBP could control the MAPK signaling pathway-involved genes expression, including P-MEK, MEK, c-Myc, P-ERK1/2, and ERK1/2, and that GDC-0994, a specific ERK1/2 inhibitor, could suppress the AIBP overexpression induced cell migration and proliferation abilities. These findings demonstrated that the ERK/MAPK signaling pathway might be stimulated by AIBP in HCC tissues, leading to increased cell invasion, migration, and proliferation. It was hypothesized that AIBP might act as a useful prognostic and diagnostic marker for HCC.

In silico analysis of polyphenols modulate bovine PPARγ to increase milk fat synthesis in dairy cattle via the MAPK signalling pathways.

This study investigates the potential phytochemicals that modulate bovine peroxisome proliferator-activated receptor gamma (PPARγ) and the Mitogen-Activated Protein Kinase (MAPK) pathways to enhance milk fat production in dairy animals. Bovine PPARγ, a key member of nuclear hormone receptor superfamily, plays a vital role in regulating metabolic, cellular differentiation, apoptosis, and anti-inflammatory responses in livestock, while the MAPK pathway is contributory in cellular processes that impact milk fat synthesis. This approach involved an all-inclusive molecular docking analysis of 10,000 polyphenols to identify potential PPARγ ligands. From this extensive screening, top 10 compounds were selected that exhibited the highest binding affinities to bovine PPARγ. Particularly, Curcumin sulphate, Isoflavone and Quercetin emerged as the most promising candidates. These compounds demonstrated superior docking scores (-9.28 kcal/mol, -9.27 kcal/mol and -7.31 kcal/mol respectively) and lower RMSD values compared to the synthetic bovine PPARγ agonist, 2,4-Thiazolidinedione (-4.12 kcal/mol), indicating a strong potential for modulating the receptor. Molecular dynamics simulations (MDS) further affirmed the stability of these polyphenols-bovine PPARγ complexes, suggesting their effective and sustained interactions. These polyphenols, known as fatty acid synthase inhibitors, are suggested to influence lipid metabolism pathways crucial to milk fat production, possibly through the downregulation of the MAPK pathway. The screened compounds showed favorable pharmacokinetic profiles, including non-toxicity, carcinogenicity, and high gastrointestinal absorption, positioning them as viable candidates for enhancing dairy cattle health and milk production. These findings may open new possibilities for the use of phytochemicals as feed additives in dairy animals, suggesting a novel approach to improve milk fat synthesis through the dual modulation of bovine PPARγ and MAPK pathways.

Targeted counteracting of overactive macrophages by melittin stable-loaded solid lipid nanoparticles alleviates cytokine storm and acute inflammatory injury

The continuous activation of macrophages play a critical role in the pathogenesis of cytokine storm (CS). Considering that CS results from the participation of multiple cytokines, the therapeutic effect of a single cytokine or its receptor-targeted blockade therapy remains uncertain. Melittin, which can systematically suppress the overexpression of proinflammatory mediators via inhibiting the mitogen-activated protein kinase and nuclear factor kappa-B pathways in activated macrophages, shows great potential in alleviating CS and acute inflammatory injury (AII). However, its clinical application is limited by its hemolytic activity, non-specific cytotoxicity and lack of targeting. In this study, a folic acid-modified and melittin stable-loaded solid lipid nanoparticle (Fa-MpG@LNP) with a core–shell structure was developed for CS control via targeted inhibition of the overproduction of proinflammatory mediators in activated macrophages with specific expression of folate receptor-β. The resultant Fa-MpG@LNP showed ideal physicochemical properties and stability, low hemolytic activity and non-specific cytotoxicity, and it can specifically bind to lipopolysaccharide (LPS)-stimulated macrophages and effectively reduce the elevated levels of proinflammatory mediators. After intravenous administration, the Fa-MpG@LNP accumulated at inflamed tissue and significantly downregulate the overproduction of proinflammatory cytokines in tissue-infiltrated macrophages, resulting in a significant decrease of cytokine concentration in inflamed tissue and serum in LPS-induced acute pneumonia mice, and finally alleviate AII with undetectable toxic side effects. These results indicate the clinical application potential of Fa-MpG@LNP in alleviating CS and its related symptoms.

β-glucan improves intestinal health of pearl gentian grouper via activation of the p38 mitogen-activated protein kinase signaling pathway

Our previous study has demonstrated that supplementation of yeast β-glucan improves intestinal health in pearl gentian grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀), accompanied by the activation of the mitogen-activated protein kinase (MAPK) signaling pathway. In this study, we investigated the effects of perturbing p38 MAPK activity using an inhibitor on the intestinal health of β-glucan-injected pearl gentian grouper to elucidate the potential molecular mechanism underlying the protective effects of β-glucan on the fish gut. The pearl gentian grouper was categorized into four groups: PBS injected (CD group), β-glucan injected at a dose of 80 mg/kg (βG group), p38 MAPK inhibitor SB203580 injected at a dose of 1 mg/kg (SB203580 group), and a combination of β-glucan (80 mg/kg) and SB203580 (1 mg/kg) injected together (βG + SB203580 group). The results revealed that the introduction of SB203580 significantly suppressed the β-glucan-induced increase in p38α and p38β mRNA expression, as well as the phosphorylation of p38 MAPK. Both the βG group and SB203580 group exhibited reduced plica height and muscularis thickness. The βG + SB203580 group displayed a significant reduction in mucin cell level; interleukin 1β (il1β) mRNA expression; induced nitric oxide synthase, tumor necrosis factor α, and IL1β concentration; catalase and total antioxidant capacity activities. Additionally, there was a significant increase in the levels of intestinal malondialdehyde in the βG + SB203580 group compared to the βG group. The inhibition of the p38 MAPK signaling halted the trend of apoptosis-related caspase molecular expression induced by β-glucan. In conclusion, β-glucan injection resulted in elevated levels of mucous cells, nonspecific immunity, antioxidant capacity, and anti-apoptosis in grouper by modulating the p38 MAPK pathway. This study offers insights into the potential molecular mechanism underlying the protective effects of β-glucan on intestinal health in pearl gentian grouper.

Mulberroside A mitigates intervertebral disc degeneration by inhibiting MAPK and modulating Ppar-γ/NF-κB pathways

BackgroundIntervertebral disc degeneration (IVDD) is a common spine disease with inflammation as its main pathogenesis. Mulberroside A (MA), isolated from herbal medicine, possesses anti-inflammatory characteristics in many diseases. Whereas, there is little exploration of the therapeutic potential of MA on IVDD. This study aimed at the therapeutic potential of MA on IVDD in vivo and in vitro and the mechanism involved.MethodsIn vitro, western blotting, RT-qPCR, and immunofluorescence analysis were implemented to explore the bioactivity of MA on interleukin-1 beta (IL-1β)-induced inflammation nucleus pulposus cells (NPCs) isolated from Sprague-Dawley male rats. In vivo, X-ray and MRI were applied to measure the morphological changes, and histological staining and immunohistochemistry were employed to investigate the histological changes of intervertebral disc sections on puncture-induced IVDD rat models.ResultsIn vitro, MA up-regulated the expression level of anabolic-related proteins (Aggrecan and Collagen II) and decreased catabolic-related proteins (Mmp2, Mmp3, Mmp9, and Mmp13) in IL-1β-induced NPCs. Furthermore, MA inhibits the production of pro-inflammatory factors (Inos, Cox-2, and Il-6) stimulated by IL-1β. Mechanistically, MA inhibited the signal transduction of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) pathways in IL-1β-induced NPCs. Moreover, MA might bind to Ppar-γ and then suppress the NF-kB pathway. In vivo experiment illustrated that MA mitigates the IVDD progression in puncture-induced IVDD model. X-ray and MRI images showed MA restore the disc height and T2-weighted signal intensity after puncturing. H&E and Safranin O/Fast Green also showed MA also alleviated morphological changes caused by acupuncture. In addition, MA reversed the expression level of Mmp13, Aggrecan, Collagen II, and Ppar-γ induced in IVDD models.ConclusionsMA inhibited degenerative phenotypes in NPCs and alleviated IVDD progression via inhibiting the MAPK and NF-κB pathways; besides, MA suppressed the NF-κB pathway was attributed to activating Ppar-γ, those supported that MA or Ppar-γ might be a potential drug or target for IVDD.

Targeting NUF2 suppresses gastric cancer progression through G2/M phase arrest and apoptosis induction.

Gastric cancer (GC), a malignant tumor with poor prognosis, is one of the leading causes of cancer-related deaths worldwide; consequently, identifying novel therapeutic targets is crucial for its corresponding treatment. NUF2 , a component of the NDC80 kinetochore complex, promotes cancer progression in multiple malignancies. Therefore, this study aimed to explore the potential of NUF2 as a therapeutic target to inhibit GC progression. Clinical samples were obtained from patients who underwent radical resection of GC at Lanzhou University Second Hospital from 2016 to 2021. Cell count assays, colony formation assays, and cell-derived xenotransplantation (CDX) models were used to determine the effects of NUF2 on GC progression. Flow cytometry was used to detect the effect of NUF2 or quercetin on cell cycle progression and apoptosis. A live-cell time-lapse imaging assay was performed to determine the effect of NUF2 on the regulation of mitotic progression. Transcriptomics was used to investigate the NUF2 -associated molecular mechanisms. Virtual docking and microscale thermophoresis were used to identify NUF2 inhibitors. Finally, CDX, organoid, and patient-derived xenograft (PDX) models were used to examine the efficacy of the NUF2 inhibitor in GC. NUF2 expression was significantly increased in GC and was negatively correlated with prognosis. The deletion of NUF2 suppressed GC progression both in vivo and in vitro . NUF2 significantly regulated the mitogen-activated protein kinase (MAPK) pathway, promoted G2/M phase transition, and inhibited apoptosis in GC cells. Additionally, quercetin was identified as a selective NUF2 inhibitor with low toxicity that significantly suppressed tumor growth in GC cells, organoids, CDX, and PDX models. Collectively, NUF2 -mediated G2/M phase transition and apoptosis inhibition promoted GC progression; additionally, NUF2 inhibitors exhibited potent anti-GC activity. This study provides a new strategy for targeting NUF2 to suppress GC progression in clinical settings.

The Necroptosis Pathway Is Upregulated in the Cornea in Mice With Ocular Graft-Versus-Host Disease.

To identify molecular signatures specific for ocular graft-versus-host disease (GVHD) by proteomic analysis of corneas from mice with GVHD. We identified differentially expressed proteins (DEPs) in corneal samples from GVHD model mice and syngeneic control mice 4 weeks after bone marrow transplantation. Data-independent acquisition analysis was performed on individual samples, and the roles of DEPs in biological pathways related to GVHD were evaluated via bioinformatics and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Three important signaling pathways were upregulated in the cornea in mice with GVHD: (1) the necroptosis pathway, (2) the mitogen-activated protein kinase (MAPK) pathway, and (3) as previously reported, the neutrophil extracellular trap (NET) pathway. In those signaling pathways, we identified new upregulated molecules, including (1) receptor-interacting protein kinase 1 (RIPK1), RIPK3, interferon regulatory factor 9, the interferon-induced double-stranded RNA-activated protein kinase lipoxygenase, and high mobility group box1 (HMGB1) which are damage-associated molecular patterns (DAMPs) in the necroptosis pathway; (2) the sequentially upregulated interleukin 1 (IL-1) receptor-associated kinase (IRAK), an evolutionarily conserved signaling intermediate in the Toll pathway (ECSIT), and p38, which is downstream of the IL-1 receptor and increased CDC42/Rac (Rac2), a Rho family GTPase in the MAPK pathway; and (3) the integrin components CR3 and macrophage-1 antigen (MAC-1), which are DAMPs, and the pyroptosis-related protein gasdermin D (GSDMD) in the NET pathway. These novel molecules may help researchers elucidate the pathogenesis of GVHD and identify new therapeutic targets for corneal changes in patients with ocular GVHD.

Porous Gelatin Methacrylate Gel Engineered by Freeze-Ultraviolet Promotes Osteogenesis and Angiogenesis.

Alveolar bone defect reconstruction is a common challenge in stomatology. To address this, a thermosensitive/photosensitive gelatin methacrylate (GelMA) gel was developed based on various air solubilities and light-curing technologies. The gel was synthesized by using a freeze-ultraviolet (FUV) method to form a porous and quickly (within 15 min) solidifying modified network structure. Unlike other gel scaffolds limited by complex preparation procedures and residual products, this FUV-GelMA gel shows favorable manufacturing ability, promising biocompatibility, and adjustable macroporous structures. The results from a rat model suggested that this gel scaffold creates a conducive microenvironment for mandible reconstruction and vascularization. In vitro experiments further confirmed that the FUV-GelMA gel promotes osteogenic differentiation of human bone marrow mesenchymal stem cells and angiogenesis of human umbilical vein endothelial cells. Investigation of the underlying mechanism focused on the p38 mitogen-activated protein kinase (MAPK) pathway. We found that SB203580, a specific inhibitor of p38 MAPK, abolished the therapeutic effects of the FUV-GelMA gel on osteogenesis and angiogenesis, both in vitro and in vivo. These findings introduced a novel approach for scaffold-based tissue regeneration in future clinical applications.

Mechanism of inhibition of melanoma by fucoxanthin simulated in vitro digestion products in cell models constructed using human malignant melanoma cells (A375) and keratinocytes (HaCaT)

Recently, the increasing incidence of malignant melanoma has become a major public health concern owing to its poor prognosis and impact on quality of life. Consuming foods with potent antitumor compounds can help prevent melanoma and maintain skin health. Fucoxanthin (FX), a naturally occurring carotenoid found in brown algae, possesses antitumor properties. However, its bioavailability, safety risks, and in vivo effects and mechanisms against melanoma remain unclear. This research focused on evaluating the safety and prospective antimelanoma impact of simulated gastrointestinal digestion products (FX-ID) on HaCaT and A375 cells.The results indicate that FX-ID exerts negative effects on mitochondria in A375 cells, increases Bax expression, releases Cytochrome C, and activates cleaved caspase-3, ultimately promoting apoptosis. Additionally, FX-ID influences the mitogen-activated protein kinase (MAPK) pathway by enhancing cyclooxygenase-2 (COX-2) and nuclear factor kappa B (NF-κB) levels, consequently facilitating apoptosis and inflammation without significantly impacting HaCaT cells. These findings provide insight into inhibitory mechanism of FX-ID against melanoma, guiding the development of functional foods for prevention.