Phosphorylation Of P38 MAPK Research Articles

HMAGEA2 as a potential diagnostic and therapeutic target for melanoma progression and metastasis.

The incidence of melanoma, a highly aggressive skin cancer, continues to increase worldwide, particularly among populations with lighter skin tones. The diagnostic challenge of melanoma lies in the absence of a distinctive clinical presentation, as its characteristics vary based on anatomical location, growth type, and histopathology. The melanoma-associated antigen (MAGE) gene family is differentially expressed in various human cancers, including melanoma. In this study, we explored the association between human MAGEA2 (hMAGEA2) expression and melanoma. Using a human melanoma tissue array, we confirmed that hMAGEA2 expression was higher in melanoma and metastatic melanoma than in normal tissues. Additionally, we used SK-MEL-5 and SK-MEL-28 cell lines to investigate the cellular and molecular mechanisms underlying melanoma progression and invasiveness. In SK-MEL-5 and SK-MEL-28 cells, hMAGEA2 overexpression accelerated cell proliferation. Conversely, the knockdown of hMAEGA2 reduced cell proliferation, colony formation, and migration significantly and induced arrest at the G2/M phase of the cell cycle. With respect to the molecular mechanism, the knockdown of hMAGEA2 decreased the phosphorylation of Akt, JNK, and p38 MAPK. Additionally, hMAGEA2 knockdown reduced tumor formation significantly at the in vivo level. Collectively, the robust correlation between hMAGEA2 and melanoma metastasis supports the potential utility of hMAGEA2 as both a diagnostic marker and novel therapeutic target for patients with melanoma metastasis.

G(1-5)-EM2, a multi-targeted agonist to opioid and growth hormone secretagogue receptors exhibited nontolerance forming antinociceptive effects in a mouse model of burn pain

Burn induced-pain (BIP) is one of the most common pain symptoms, which seriously affects the quality of sufferer life. Researches show that multi-targeted drug therapies offer superior efficacy and fewer side effects compared to single-target drug therapies. Consequently, in this study, we developed G(1-5)-EM2, a multi-targeted peptide designed to target μ-opioid receptor and the growth hormone secretagogue receptor 1α (GHS-R1α), and explored its antinociceptive effects on burn injury pain. Calcium mobilization experiments revealed that G(1-5)-EM2 demonstrated weak multi-agonist activities to μ-opioid receptor and κ-opioid receptor as well as GHS-R1α in vitro. Near-infrared fluorescence imaging experiments demonstrated that G(1-5)-EM2 could penetrate the blood-brain barrier (BBB) and access the brain following intravenous injection. The enzymatic stability of G(1-5)-EM2 was significantly enhanced compared to EM2. Our results indicated that intrathecal administration of G(1-5)-EM2 mitigated mechanical allodynia and thermal hyperalgesia in BIP. These antinociceptive effects of G(1-5)-EM2 were partially mediated through μ-opioid receptor and GHS-R1α. Moreover, intrathecal administration of G(1-5)-EM2 significantly decreased burn-induced up-regulation of phosphorylated p38 MAPK, phosphorylated NF-κBp65 and TRPV1 in the ipsilateral spinal cord, reduced the levels of IL-1β, IL-6 and TNF-α in serum, and enhanced wound healing in burned skin. Repeated intrathecal administration of G(1-5)-EM2 produced a non-tolerance-forming antinociception in BIP. These results suggest that the multi-targeted peptide G(1-5)-EM2 exhibits a novel role in alleviating BIP with fewer side effects and may represent a promising strategy for developing new analgesic drugs.

Maresin-1 Ameliorates Sepsis-Induced Microglial Activation Through Modulation of the P38 MAPK Pathway.

Sepsis is a life-threatening disease characterized by a dysregulated immune response to infection, often leading to neuroinflammation. As a known immunomodulator, Maresin-1 (MaR1) may have potential applications in the treatment of sepsis-induced neuroinflammation, but its effects in this context are unknown. We used a mouse cecum ligation and puncture (CLP)-induced sepsis model and an in vitro lipopolysaccharide (LPS)-induced neuroinflammatory model of BV2 microglia. Expression of microglial cell markers (IBA1, CD11B, CD68, CD86 and CD206) and pro-inflammatory markers (iNOS and COX2) was assessed. The role of MaR1 in regulating the P38 MAPK pathway was explored using the P38 MAPK inhibitor SB203580. In the CLP model, an increased proportion of M1-type microglia was observed, and MaR1 was able to reverse it. However, the combination of SB203580 and MaR1 did not enhance the therapeutic effect compared to SB20580 alone. In vitro experiments, MaR1 inhibited LPS-induced P38 MAPK nuclear translocation and decreased the expression of pro-inflammatory markers such as iNOS and COX2. As with the animal results, no stacking effect could be obtained with the co-administration of SB203580 and MaR1. Our findings suggest that MaR1 attenuates sepsis-induced neuroinflammation mainly by inhibiting phosphorylation of P38 MAPK in microglial cells. This suggests that MaR1 may have a potential therapeutic role in the treatment of sepsis neuroinflammation.

Reversing metabolic reprogramming by CPT1 inhibition with etomoxir promotes cardiomyocyte proliferation and heart regeneration via DUSP1 ADP-ribosylation-mediated p38 MAPK phosphorylation

The neonatal mammalian heart has a remarkable regenerative capacity, while the adult heart has difficulty to regenerate. A metabolic reprogramming from glycolysis to fatty acid oxidation occurs along with the loss of cardiomyocyte proliferative capacity shortly after birth. In this study, we sought to determine if and how metabolic reprogramming regulates cardiomyocyte proliferation. Reversing metabolic reprogramming by carnitine palmitoyltransferase 1 (CPT1) inhibition, using cardiac-specific Cpt1a and Cpt1b knockout mice promoted cardiomyocyte proliferation and improved cardiac function post-myocardial infarction. The inhibition of CPT1 is of pharmacological significance because those protective effects were replicated by etomoxir, a CPT1 inhibitor. CPT1 inhibition, by decreasing poly(ADP-ribose) polymerase 1 expression, reduced ADP-ribosylation of dual-specificity phosphatase 1 in cardiomyocytes, leading to decreased p38 MAPK phosphorylation, and stimulation of cardiomyocyte proliferation. Our present study indicates that reversing metabolic reprogramming is an effective strategy to stimulate adult cardiomyocyte proliferation. CPT1 is a potential therapeutic target for promoting heart regeneration and myocardial infarction treatment.

Protective effect of 6'-Sialyllactose on LPS-induced macrophage inflammation via regulating Nrf2-mediated oxidative stress and inflammatory signaling pathways.

Macrophages play a central role in cardiovascular diseases, like atherosclerosis, by accumulating in vessel walls and inducing sustained local inflammation marked by the release of chemokines, cytokines, and matrix-degrading enzymes. Recent studies indicate that 6'-sialyllactose (6'-SL) may mitigate inflammation by modulating the immune system. Here, we examined the impact of 6'-SL on lipopolysaccharide (LPS)-induced acute inflammation using RAW 264.7 cells and a mouse model. In vivo, ICR mice received pretreatment with 100 mg/kg 6'-SL for 2 h, followed by intraperitoneal LPS injection (10 mg/kg) for 6 h. In vitro, RAW 264.7 cells were preincubated with 6'-SL before LPS stimulation. Mechanistic insights were gained though Western blotting, qRT-PCR, and immunofluorescence analysis, while reactive oxygen species (ROS) production was assessed via DHE assay. 6'-SL effectively attenuated LPS-induced p38 MAPK and Akt phosphorylation, as well as p65 nuclear translocation. Additionally, 6'-SL inhibited LPS-induced expression of tissue damage marker MMP9, IL-1β, and MCP-1 by modulating NF-κB activation. It also reduced ROS levels, mediated by p38 MAPK and Akt pathways. Moreover, 6'-SL restored LPS-suppressed Nrf2 and HO-1 akin to specific inhibitors SB203580 and LY294002. Consistent with in vitro results, 6'-SL decreased oxidative stress, MMP9, and MCP-1 expression in mouse endothelium following LPS-induced macrophage activation. In summary, our findings suggest that 6'-SL holds promise in mitigating atherosclerosis by dampening LPS-induced acute macrophage inflammation.

DLK1 and DLK2, two non-canonical ligands of NOTCH receptors, differentially modulate the osteogenic differentiation of mesenchymal C3H10T1/2 cells

BackgroundC3H10T1/2 is a mesenchymal cell line capable of differentiating into osteoblasts, adipocytes and chondrocytes. The differentiation of these cells into osteoblasts is modulated by various transcription factors, such as RUNX2. Additionally, several interconnected signaling pathways, including the NOTCH pathway, play a crucial role in modulating their differentiation into mature bone cells. We have investigated the roles of DLK1 and DLK2, two non-canonical inhibitory ligands of NOTCH receptors, in the osteogenic differentiation of C3H10T1/2 cells.ResultsOur results corroborate existing evidence that DLK1 acts as an inhibitor of osteogenesis. In contrast, we demonstrate for the first time that DLK2 enhances this differentiation process. Additionally, our data suggest that NOTCH2, 3 and 4 receptors may promote osteogenesis, as indicated by their increased expression during this process, whereas NOTCH1 expression, which decreases during cell differentiation, might inhibit osteogenesis. Moreover, treatment with DAPT, a NOTCH signaling inhibitor, impeded osteogenic differentiation. We have confirmed the increase in ERK1/2 MAPK and p38 MAPK phosphorylation in C3H10T1/2 cells induced to differentiate to osteoblasts. Our new findings reveal increased ERK1/2 MAPK phosphorylation in differentiated C3H10T1/2 cells with a decrease in DLK1 expression or an overexpression of DLK2, which is coincident with the behavior of those transfectants where we have detected an increase in osteogenic differentiation. Additionally, p38 MAPK phosphorylation increases in differentiated C3H10T1/2 cells with reduced DLK1 levels.ConclusionsOur results suggest that DLK1 may inhibit osteogenesis, while DLK2 may promote it, by modulating NOTCH signaling and the phosphorylation of ERK1/2 and p38 MAPK pathways. Given the established inhibitory effect of DLK proteins on NOTCH signaling, these new insights could pave the way for developing future therapeutic strategies aimed at treating bone diseases.

Novel role of human epicardial adipocyte-derived SPARCL1 in suppression of postoperative atrial fibrillation in patients undergoing cardiovascular surgery

Abstract Background Postoperative atrial fibrillation (POAF) occurs in 20-50% after cardiovascular surgery and is associated with the short and long-term morbidity/mortality. The epicardial adipose tissue (EAT) may have a potential role to regulate the incidence of POAF. Purpose We explored the possible role of human epicardial adipocyte-derived adipokines in the regulation of the myocardial redox state and POAF. Methods We prospectively evaluated 149 patients without known AF who underwent scheduled open-heart cardiovascular surgery between May 2020 and November 2022. They were divided into POAF or Non-POAF group and followed up after discharge (476.6 ± 290.0 days). POAF was defined as AF lasting more than 30 seconds after the surgery. Human EAT samples were obtained from these patients during surgery and the preadipocytes were isolated. Preadipocytes were terminally differentiated to mature adipocytes and mRNAs were extracted. Genome-wide expression profiling of 6 vs. 6 matched samples of the POAF and Non-POAF groups was performed using Microarray analysis, and the results were validated with qPCR in all the cohort samples. The effects of secreted adipokines on the cardiomyocytes were assessed in terms of oxidative stress. Superoxide and whole reactive oxygen species (ROS) were evaluated with luminometry and live-cell fluorescent probes respectively. As the oxidative stress associated signalling, the phosphorylation of ERK and p38-MAPK were evaluated with western blotting. Angiotensin II (Ang-II) was used to induce oxidative stress and phosphorylation of MAPK. Results POAF was observed in 53 patients (36%). Microarray analysis (n = 6) revealed that there were 132 down- or up-regulated cording genes in epicardial adipocytes of the POAF group compared to the Non-POAF group. Of these genes, 11 genes cording secretable molecules were validated by qPCR (n = 69), showing that only SPARCL1 had significantly downregulated in the POAF group compared to the Non-POAF group (P = 0.005). Superoxide and ROS were induced by Ang II (P < 0.01) and attenuated by SPARCL1 dose-dependent manner (P < 0.01) in neonatal rat cardiomyocytes. The phosphorylation of ERK and p38-MAPK were induced by Ang II (P < 0.01) and attenuated by SPARCL1 (P < 0.01) dose-dependently. Co-culture of human induced pluripotent stem cell-derived atrial cardiomyocytes (iPS-ACM) and human epicardial adipocytes revealed that the adipocytes derived from Non-POAF group suppressed the superoxide (P = 0.002) and ROS (P = 0.02) in iPS-ACM compared to POAF group. Kaplan-Meier survival analysis revealed that the POAF group (P = 0.01) and low SPARCL1 expression in epicardial adipocytes (P = 0.018) were associated with a higher incidence of long-term adverse cardiovascular events after surgery. Conclusion: SPARCL1 derived from epicardial adipocytes may play an important role in the suppression of POAF and long-term cardiovascular events via improving the myocardial redox state.

GSK3179106 ameliorates lipopolysaccharide-induced inflammation and acute lung injury by targeting P38 MAPK

Acute lung injury (ALI) is a serious acute respiratory disease that can cause alveolar-capillary barrier disruption and pulmonary edema, respiratory failure and multiple organ dysfunction syndrome. However, there is no effective drugs in clinic until now. GSK3179106 has been reported can alleviate intestinal stress syndrome, but the protective effect of GSK3179106 on ALI has not been elucidated. The present study will evaluate the pharmacological activity of GSK3179106 on lipopolysaccharide (LPS)-induced inflammation and lung injury and clarify its underlying mechanism. We found that GSK3179106 significantly attenuated LPS-induced lung injury in vivo, accompanied by inhibited infiltration of inflammatory cells and reduced expression of inflammatory cytokines. Meanwhile, GSK3179106 dose-dependently reduced the LPS-induced IL-6 expression both in protein and gene levels in macrophages. Mechanistically, GSK3179106 could inhibited the phosphorylation of P38 MAPK induced by LPS. Importantly, results showed that there is a direct combination between GSK3179106 and P38 MAPK. Together, our findings not only clarified the anti-inflammatory activity of GSK3179106 but also discovered its new clinical indications. Therefore, compound GSK3179106 may be a potential candidate for the treatment of acute inflammatory diseases.

Integrating network pharmacology, molecular docking, and experimental validation to reveal the mechanism of Radix Rehmanniae in psoriasis.

Radix Rehmanniae (RR) plays an important role in treating psoriasis. However, the active compounds of RR and potential mechanisms are unclear. The current study was designed to investigate the potential active ingredients, targets, and mechanisms of RR in treating psoriasis through network pharmacology, molecular docking, and vitro experiments. Initially, the TCMSP database and literature retrieval were used to access the active ingredients of RR. The psoriasis target proteins were obtained from Therapeutic Target Database, OMIM, GeneCards, and DrugBank databases. The target proteins were then converted into target genes using Uniprot. Secondly, overlapping genes were obtained through Venn online tool. Then, protein-protein interactions network diagram is finished by STRING database. Next, Cytoscape software was used to acquire the top 10 hub proteins; gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis were then used to predict possible mechanisms. Afterwards, molecular docking validation of the active ingredients with the main targets was performed by AutoDock software. Finally, lipopolysaccharides induced RAW264.7, to assess the effects and molecular mechanisms by MTT, RT-qPCR, and Western blot assays. Overall, there are 20 effective compounds and 33 targets involved in biological processes including apoptosis, intracellular signaling, vasodilation, and mitogen-activated protein kinase (MAPK) signaling cascade. The docking results showed strong binding capacity between the active ingredients and targets. We verified aucubin as the key active ingredient, tumor necrosis factor α, and IL6 as the core targets, and focused on the p38MAPK protein pathway. Cellular experiments showed that aucubin down-regulated the phosphorylated p38MAP protein and reduced the expression of tumor necrosis factor α mRNA, IL6 mRNA, and IL1βmRNA. In summary, RR is featured with multicomponent, multi-target, and multi-pathway in treating psoriasis; the preliminary mechanism may be associated with the down-regulation of p38MAPK phosphorylation and curbing the expression of inflammatory factor by aucubin. This paper provides the scientific basis for Traditional Chinese medicine treating psoriasis.

Bioactivities of Quinic Acids from Vitex rotundifolia Obtained by Supercritical Fluid Extraction.

Acyl-quinic acids (AQAs), present in various plants with many health benefits, are regarded as therapeutic agents in the prevention and treatment of chronic and cardiovascular diseases. The molecular network-guided identification of ten AQA compounds, two new (5 and 7) and eight known compounds, were isolated from V. rotundifolia L. f. by using a newly applied extraction method. Their structures were determined through spectroscopic means, reaction mixtures, and modified Mosher and PGME techniques. These compounds were assessed for their anti-inflammatory and antioxidant capabilities. Notably, compounds 1, 3, 4, 6, 8, and 9 exhibited notable DPPH radical scavenging activity. In LPS-induced HT-29 cells, compounds 2-7 significantly inhibited IL-8 production. Furthermore, compounds 3-5 and 7 markedly suppressed NO production, while compounds 1-10 effectively inhibited IL-6 production in LPS-induced RAW264.7 cells. Western blot analyses revealed that compounds 3-5, and 7 reduced iNOS and COX-2 expression, and compounds 2-5, 7, and 8 also diminished the expression levels of p38 MAPK phosphorylation. Docking studies demonstrated the active compounds' binding affinity with the IL-8, iNOS, COX-2, and p38 MAPK proteins through interactions with essential amino acids within the binding pockets of complexes. The findings suggest that compounds 1, 3, 4, 6, 8, and 9, and compounds 3-5, and 7, hold promise as potential therapeutic agents for treating antioxidative and inflammatory diseases, respectively.

Ursodeoxycholic acid alleviates fat embolism syndrome-induced acute lung injury by inhibiting the p38 MAPK/NF-κB signalling pathway through FXR

Acute lung injury (ALI) caused by fat embolism syndrome (FES) is a disease with high mortality. This study aimed to explore the roles of ursodeoxycholic acid (UDCA) in FES-induced ALI and its underlying mechanisms. An ALI mouse model was established by allografting mouse perinephric fat. For in vitro experiments, human pulmonary microvascular endothelial cells (HPMEC) were treated with FFAs. The effects of UDCA on the expression of farnesoid X receptor (FXR) and the inflammatory response in endothelial cells were investigated. UDCA significantly inhibited the inflammatory response and the expression of proinflammatory markers during FES-induced ALI. UDCA markedly decreased TNF-α and IL-1β expression in vitro. UDCA administration markedly upregulated FXR expression and significantly reduced the phosphorylation of p38 MAPK and NF-κB p65. Knock down FXR expression decreased the effect of UDCA in vivo. Furthermore, knock down FXR expression and overexpressing FXR increased and decreased the inflammatory response, respectively, in vitro. Moreover, administration of a p38 MAPK activator reversed the anti-inflammatory effect of FXR overexpression. UDCA ameliorated inflammation during FES-induced ALI by suppressing p38 MAPK/NF-κB signalling and activating FXR. These findings provide new evidence for the potential of UDCA for FES-induced ALI treatment.

Structural characterization and immunoregulatory mechanism of a low-molecular-weight polysaccharide from lotus root

The extraction of polysaccharide from lotus root was highly homogenized, and the structure of the polysaccharide was not clear. Herein, we report a hot water method combined with α-amylase that was applied to extract lotus root polysaccharide. After purified, a lotus root polysaccharide fraction LP60-a with high purity and low molecule weight was obtained. Systematic characterization of the structure of LP60-a was achieved by monosaccharide composition, methylation and NMR analysis, showing that LP60-a was composed of α-1,6-glucan linked with a small amount of arabinogalactan. Conformational determination showed that LP60-a was a three-helix polysaccharide with random coil conformation. Furtherly, the immunomodulatory activities of LP60-a were investigated in RAW264.7 macrophages. The data indicated that LP60-a could enhance the proliferation and phagocytosis of macrophages significantly, and induce the expression of NO and TNF-α in macrophages without causing inflammation. Moreover, LP60-a promoted the phosphorylation of MAPK p38 and JNK, as well as NF-κB p65, indicating that LP60-a could activate RAW264.7 cells through MAPK and NF-κB signaling pathways. In conclusion, the results imply that LP60-a could enhance the immune function of macrophages, presenting a possibility to play a role as an immunomodulatory agent in dietary supplements.

Capsular polysaccharide from the marine bacterium Cobetia marina induces apoptosis via both caspase-dependent and mitochondria-mediated pathways in HL-60 cells

In the present study, we investigated the antiproliferative effect of the capsular polysaccharide (CPS) from marine Gram-negative bacterium Cobetia marina (formerly C. pacifica) KMM 3878 against human leukemia cells in vitro and the potential molecular mechanism underlying this activity. Our results showed that the CPS could inhibit the proliferation of HL-60 cells in a dose-dependent manner with no effect on normal PBMC cells. HL-60 cells treated with the CPS exhibited typical morphologic and biochemical signs of apoptosis. We found that the CPS caused the collapse of mitochondrial transmembrane potential (ΔΨm), activated caspases-8,-9, and − 3, decreased the ratio of anti-apoptotic Bcl-2 and pro-apoptotic Bax proteins, increased ROS production and TNF-α secretion, and stimulated phosphorylation of p38 MAPK and p53 in HL-60 cells. Taken together, these data suggest that both extracellular and intracellular signaling pathways contribute to the CPS-induced apoptosis in HL-60 cells.

Unravelling bisphenol A-induced hepatotoxicity: Insights into oxidative stress, inflammation, and energy dysregulation

Bisphenol A (BPA), a prevalent plastic monomer and endocrine disruptor, negatively impacts metabolic functions. This study examines the chronic effects of eco-relevant BPA concentrations on hepatotoxicity, focusing on redox balance, inflammatory response, cellular energy sensors, and metabolic homeostasis in male Swiss albino mice. Chronic BPA exposure resulted in reactive oxygen species (ROS) accumulation, altered hepatic antioxidant defense, lipid peroxidation, and NOX4 expression, leading to reduced cell viability. Additionally, BPA exposure significantly upregulated hepatic pro-inflammatory cytokine genes (Tnf-α, Il-1β, Il-6), NOS2, and arginase II, correlating with increased TLR4 expression, NF-κB phosphorylation, and a dose-dependent decrease in IκBα levels. BPA-induced NF-κB nuclear localization and inflammasome activation (NLRP3, cleaved caspase-1, IL-1β) established an inflammatory milieu. Perturbations in hepatic AMPKα phosphorylation, SIRT1, and PGC-1α, along with elevated p38 MAPK phosphorylation and ERα expression, indicated BPA-induced energy dysregulation. Furthermore, increased PLA2G4A, COX1, COX2, and PTGES2 expression in BPA-treated liver correlated with hyperlipidemia, hepatic FASN expression, steatosis, and visceral adiposity, likely due to disrupted energy sensors, oxidative stress, and inflammasome activation. Elevated liver enzymes (ALP, AST, ALT) and apoptotic markers indicated liver damage. Notably, N-acetylcysteine (NAC) priming reversed BPA-induced hepatocellular ROS accumulation, NF-κB-inflammasome activation, and intracellular lipid accumulation, while upregulating cellular energy sensors and attenuating ERα expression, suggesting NAC's protective effects against BPA-induced hepatotoxicity. Pharmacological inhibition of the NF-κB/NLRP3 cascade in BAY11-7082 pretreated, or NLRP3 immunodepleted hepatocytes reversed BPA's negative impact on SIRT1/p-AMPKα/PGC-1α and intracellular lipid accumulation, providing mechanistic insights into BPA-induced metabolic disruption.

Deletion of p38 MAPK in macrophages ameliorates peritoneal fibrosis and inflammation in peritoneal dialysis

One of the most common causes of peritoneal dialysis withdrawal is ultrafiltration failure which is characterized by peritoneal membrane thickening and fibrosis. Although previous studies have demonstrated the inhibitory effect of p38 MAPK inhibitors on peritoneal fibrosis in mice, it was unclear which specific cells contribute to peritoneal fibrosis. To investigate the role of p38 MAPK in peritoneal fibrosis more precisely, we examined the expression of p38 MAPK in human peritoneum and generated systemic inducible p38 MAPK knockout mice and macrophage-specific p38 MAPK knockout mice. Furthermore, the response to lipopolysaccharide (LPS) was assessed in p38 MAPK-knocked down RAW 264.7 cells to further explore the role of p38 MAPK in macrophages. We found that phosphorylated p38 MAPK levels were increased in the thickened peritoneum of both human and mice. Both chlorhexidine gluconate (CG)-treated systemic inducible and macrophage-specific p38 MAPK knockout mice ameliorated peritoneal thickening, mRNA expression related to inflammation and fibrosis, and the number of αSMA- and MAC-2-positive cells in the peritoneum compared to CG control mice. Reduction of p38 MAPK in RAW 264.7 cells suppressed inflammatory mRNA expression induced by LPS. These findings suggest that p38 MAPK in macrophages plays a critical role in peritoneal inflammation and thickening.

FPS-ZM1 attenuates the deposition of lipid in the liver of diabetic mice by sterol regulatory element binding protein-1c

BackgroundNonalcoholic fatty liver disease (NAFLD) shares common pathogenic mechanisms of type 2 diabetes mellitus (T2DM) with upregulated advanced glycation end products (AGEs). Here, we aim to investigate the effect of FPS-ZM1, an inhibitor for receptor for AGEs (RAGE), on lipid deposition in the liver of mice.MethodsKK-Ay mice were used as models of T2DM with NAFLD, while C57BL/6j mice were controls. Additionally, KK-Ay mice were treated with DMSO (with a concentration of 1%), with or without FPS-ZM1 (3 mg/kg/day, i.p). Lipid deposition in hepatocytes was observed using oil red O stain. Levels of AGEs and RAGE were measured. Sterol regulatory element-binding protein-1c (SREBP-1c), as well as nuclear factor κB p65 (p65 nfκb) and mitogen-activated protein kinase p38 (p38 MAPK), were also detected.ResultsLipid deposition is increased in the hepatocytes of KK-Ay mice compared to C57BL/6j mice. In addition, not only were the levels of AGEs elevated in plasma, but also the levels of RAGE in liver tissue. Although total SREBP-1c levels did not change in the liver of diabetic mice, mature SREBP-1c increased in KK-Ay mice with diabetes mellitus. Moreover, diabetic mice showed increased levels of phosphorylated-p65 nfκb (p-p65 nfκb) and phosphorylated-p38 MAPK (p-p38 MAPK). On the contrary, FPS-ZM1 decreased lipid deposition in liver cells, as well as mature SREBP-1c, p-p65 nfκb and p-p38 MAPK levels in liver tissue.ConclusionGenerally, FPS-ZM1 may attenuate lipid deposition in hepatocytes of diabetic mice via SREBP-1c down-regulation. This may depend on the downregulation of p65 nfκb and p38 MAPK phosphorylation.

Endothelial α1-adrenergic receptor activation improves cardiac function in septic mice via PKC-ERK/p38MAPK signaling pathway

Cardiomyopathy is particularly common in septic patients. Our previous studies have shown that activation of the alpha 1 adrenergic receptor (α1-AR) on cardiomyocytes inhibits sepsis-induced myocardial dysfunction. However, the role of cardiac endothelial α1-AR in septic cardiomyopathy has not been determined. Here, we identified α1-AR expression in mouse and human endothelial cells and showed that activation of α1-AR with phenylephrine (PE) improved cardiac function and survival by preventing cardiac endothelial injury in septic mice. Mechanistically, activating α1-AR with PE decreased the expression of ICAM-1, VCAM-1, iNOS, E-selectin, and p-p38MAPK, while promoting PKC and ERK1/2 phosphorylation in LPS-treated endothelial cells. These effects were abolished by a PKC inhibitor or α1-AR antagonist. PE also reduced p65 nuclear translocation, but this suppression is not blocked by PKC inhibition. Treatment with U0126 (a specific ERK1/2 inhibitor) reversed the effects of PE on p38MAPK phosphorylation. Our results demonstrate that cardiac endothelial α1-AR activation prevents sepsis-induced myocardial dysfunction in mice by inhibiting the endothelial injury via PKC-ERK/p38MAPK signaling pathway and a PKC-independent inhibition of p65 nuclear translocation. These findings offer a new perspective for septic patients with cardiac dysfunction by inhibiting cardiac endothelial cell injury through α1-AR activation.

Surface Molecularly Engineered Mitochondria Conduct Immunophenotype Repolarization of Tumor-Associated Macrophages to Potentiate Cancer Immunotherapy.

Reprogramming tumor-associated macrophages (TAMs) to an inflammatory phenotype effectively increases the potential of immune checkpoint blockade (ICB) therapy. Artificial mitochondrial transplantation, an emerging and safe strategy, has made brilliant achievements in regulating the function of recipient cells in preclinic and clinic, but its performance in reprogramming the immunophenotype of TAMs has not been reported. Here, the metabolism of M2 TAMs is proposed resetting from oxidative phosphorylation (OXPHOS) to glycolysis for polarizing M1 TAMs through targeted transplantation of mannosylated mitochondria (mPEI/M1mt). Mitochondria isolated from M1 macrophages are coated with mannosylated polyethyleneimine (mPEI) through electrostatic interaction to form mPEI/M1mt, which can be targeted uptake by M2 macrophages expressed a high level of mannose receptors. Mechanistically, mPEI/M1mt accelerates phosphorylation of NF-κB p65, MAPK p38 and JNK by glycolysis-mediated elevation of intracellular ROS, thus prompting M1 macrophage polarization. In vivo, the transplantation of mPEI/M1mt excellently potentiates therapeutic effects of anti-PD-L1 by resetting an antitumor proinflammatory tumor microenvironmentand stimulating CD8 and CD4 T cells dependent immune response. Altogether, this work provides a novel platform for improving cancer immunotherapy, meanwhile, broadens the scope of mitochondrial transplantation technology in clinics in the future.

CDK5RAP3 Inhibition by Hypoxia Activates P38MAPK to Facilitate Angiogenesis.

CDK5RAP3 is a recognized tumor suppressor that inhibits Chk1 and Chk2 and activates p53, all of which are involved with mediating toxin-induced apoptosis of cancer cells. CDK5RAP3 also inhibits p38MAPK phosphorylation and activity via mediating a p38 interaction with wild-type p53-induced phosphatase 1. This study aimed to investigate the antiangiogenic activity of CDK5RAP3 and its molecular mechanisms in human umbilical vein endothelial cells (HUVECs) under conditions of hypoxic conditions. Angiogenesis was induced in HUVECs mainly by vascular endothelial growth factor (VEGF). The CDK5RAP3 levels of HUVECs were reduced in a time-dependent manner in response to hypoxic treatment at 2% O2. The reduction of CDK5RAP3 was accompanied with increased p38MAPK phosphorylation and activation. Moderate hypoxia was found to significantly increase secreted VEGF concentrations, and the hypoxic conditioned medium (HCM) markedly enhanced proliferation, migration, and tube formation. Our findings indicate that moderate hypoxia facilitates angiogenesis by inhibiting CDK5RAP3. CDK5RAP3 exhibits a clear regulatory role in vascular regeneration, as downregulating its expression in endothelial cells enhances VEGF synthesis and subsequently improves cell migration and lumen formation capability. This study presents evidence indicating that moderate hypoxia facilitates angiogenesis by inhibiting CDK5RAP3, demonstrating the potential for CKD5RAP3 to be a potent antiangiogenic agent in angiogenesis regulation of cancer, ischemic diseases, and wound healing.

Pyrazole derivatives ameliorate synovial inflammation in collagen-induced arthritis mice model via targeting p38 MAPK and COX-2.

The type II collagen-induced arthritis (CIA) model and human rheumatoid arthritis exhibit similar characteristics. Both diseases involve the production of inflammatory cytokines and other mediators, triggering an inflammatory cascade linked to bone and cartilage damage. Recently, new pyrazole compounds with various pharmacological activities, including antimicrobial, anticancer, anti-inflammatory, and analgesic agents, have been reported. Our aim is to evaluate the therapeutic effectiveness of two newly synthesized pyrazole derivatives, M1E and M1G, in reducing inflammation and oxidative stress in a mouse model of collagen-induced arthritis. Arthritis was induced in DBA/1J mice, and the therapeutic effect of the M1E and M1G is assessed by measuring the arthritic index, quantifying the expression of inflammatory genes such as p38 MAPK, COX-2, IL1β, MMP3, and TNF-α using real-time PCR and analyzing protein expression using western blotting for phosphorylated p38 MAPK and COX-2. Oxidative stress markers and hind paws joint histopathology were also evaluated. Treatment with the two pyrazole derivatives significantly (p < 0.001) improved the arthritic score; downregulated the expression of inflammatory genes p38 MAPK, COX-2, IL1β, MMP3, and TNF-α; and reduced the protein expression of phosphorylated p3MAPK and COX-2. In addition, both compounds ameliorated oxidative stress by increasing the activities of SOD and reducing the formation of MDA in the paw tissue homogenates. Both M1E and M1G significantly (p < 0.001) improved the pathological features of synovitis. The pyrazole derivatives, M1E and M1G, significantly reduced the arthritic score and the inflammatory cytokine expression, improved synovitis histopathology, and ameliorated oxidative stress in the CIA mice model.