Dexmedetomidine ameliorates lipopolysaccharide-induced acute lung injury by inhibiting the PI3K/Akt/FoxO1 signaling pathway

Curcumin modulates the PTEN/PI3K/AKT pathway to alleviate inflammation and oxidative stress in PM2.5-Induced chronic obstructive pulmonary disease

Ambient fine particulate matter (PM2.5) contributes to the onset and escalation of chronic obstructive pulmonary disease (COPD) through the induction of inflammatory reactions and oxidative stress. Curcumin is a natural polyphenolic compound renowned for the potent antioxidant and anti-inflammatory properties. This research utilized a PM2.5-induced COPD mouse model and BEAS-2B cell line to explore the protective mechanisms of curcumin. The results showed that PM2.5 impaired pulmonary function, exacerbated airway inflammation, and caused structural damage to lung tissue. Elevated levels of inflammatory cytokines such as IL-6, IL-1β, and TNF-α, increased malondialdehyde, and reduced activities of antioxidant enzymes catalase and superoxide dismutase were observed in both mice and BEAS-2B cell line. PM2.5 exposure also suppressed PTEN expression and activated PI3K/AKT signal, and the downstream molecule NF-κB was activated and FoxO1 activity was inhibited. PTEN overexpression partially reversed PM2.5-induced inflammation and oxidative stress in vitro. Curcumin enhanced PTEN expression, inhibited PI3K/AKT and NF-κB activation, and restored FoxO1 activity, alleviating airway inflammation and oxidative stress, while PTEN inhibition attenuated the ameliorating effects of curcumin in vitro and in vivo. In summary, PM2.5 exposure induces COPD inflammation and oxidative stress by disrupting PTEN/PI3K/AKT signaling and curcumin significantly alleviates these effects partially through PTEN/PI3K/AKT signal.

Research status and advances in dexmedetomidine for sepsis‑induced multiple organ dysfunction syndrome (Review)

Sepsis‑induced organ dysfunction syndrome (ODS) arises from a dysregulated response to infection, leading to multiple life‑threatening organ dysfunctions, and is a common complication in critically ill patients. Sepsis results in varying degrees of injury to the brain, lungs, kidneys and liver, culminating in immune dysfunction and multiple ODS (MODS). Current evidence indicates a direct correlation between the severity of organ injury and the prognosis of septic patients. Understanding the mechanisms of MODS in sepsis and developing effective management strategies are vital research areas. The protective effects of dexmedetomidine (DEX) on sepsis are well established, demonstrating its capacity to mitigate injuries to the brain, lungs, kidneys, liver and immune system. The present study reviews recent research progress on the role and mechanisms of action of DEX in the treatment of sepsis.

Identification of Hub Genes for Dexmedetomidine Alleviation of Limb Ischemia-Reperfusion-Induced Lung Injury in Rats by Transcriptomic

Background

Limb ischemia-reperfusion (LIR), a prevalent clinical condition, frequently precipitates acute lung injury (ALI). Dexmedetomidine (DEX), a selective alpha2-adrenergic receptor agonist, mitigates LIR-induced ALI. However, its underlying mechanisms remain incompletely elucidated. This study aimed to identify hub genes implicated in DEX-mediated protection against LIR-ALI in rats.

Methods

Sprague-Dawley rats were allocated into five groups (n = 3 per group): Sham (femoral artery exposure without occlusion), LIR, LIR + DEX, LIR + Inhibitor, and LIR + DEX + Inhibitor. LIR was induced by clamping the femoral arteries for 3 hours, followed by reperfusion. DEX (50 μg/kg) or Atipamezole (alpha2-receptor inhibitor, 250 μg/kg) was administered prior to ischemia. Lung injury was evaluated via hematoxylin-eosin staining, wet/dry ratio assessment, and quantification of IL-1beta, TNF-alpha, malondialdehyde (MDA), and superoxide dismutase (SOD) levels. RNA sequencing was performed to identify differentially expressed genes (DEGs), followed by functional enrichment analysis, protein-protein interaction (PPI) network construction, and hub gene identification. Gene-gene interaction (GGI) networks were established. Polymerase chain reaction (PCR) and enzyme linked immunosorbent assay (ELISA) validation was conducted.

Results

LIR induced severe lung injury and inflammation, both of which were attenuated by DEX pretreatment. RNA sequencing identified 2,302 DEGs1, 471 DEGs2, 340 DEGs3, and 1,407 DEGs4. After intersection and subtraction analyses, 255 DEX-associated DEGs (DEGs-Dex) and 290 inhibitor-associated DEGs (DEGs-In) were identified, with enrichment in Wnt/PI3K-Akt signaling (DEX) and glycerolipid/butanoate metabolism (In). Nine Hub-Dex genes and four Hub-In genes were identified, among which Selp and Tars1 exhibited a strong positive correlation (correlation = 0.55, P < 0.05). Six hub genes (Tars1, Atf4, Ep300, Sphk1, AABR07051376.1, and Mmp9) were validated.

Conclusion

Six hub genes associated with DEX-mediated protection against LIR-ALI were identified, providing mechanistic insights and potential therapeutic targets for intervention.

Inhibition of IRE1α/XBP1 axis alleviates LPS-induced acute lung injury by suppressing TXNIP/NLRP3 inflammasome activation and ERK/p65 signaling pathway

BACKGROUND

Acute lung injury or acute respiratory distress syndrome (ALI/ARDS) is a devastating clinical syndrome with high incidence and mortality rates. IRE1α-XBP1 pathway is one of the three major signaling axes of endoplasmic reticulum stress that is involved in inflammation, metabolism, and immunity. The role and potential mechanisms of IRE1α-XBP1 axis in ALI/ARDS has not well understood.

METHODS

The ALI murine model was established by intratracheal administration of lipopolysaccharide (LPS). Hematoxylin and eosin (H&E) staining and analysis of bronchoalveolar lavage fluid (BALF) were used to evaluate degree of lung injury. Inflammatory responses were assessed by ELISA and RT-PCR. Apoptosis was evaluated using TUNEL staining and western blot. Moreover, western blot, immunohistochemistry, and immunofluorescence were applied to test expression of IRE1α, XBP1, NLRP3, TXNIP, IL-1β, ERK1/2 and NF-κB p65.

RESULTS

The expression of IRE1α significantly increased after 24 h of LPS treatment. Inhibition of the IRE1α-XBP1 axis with 4µ8C notably improved LPS-induced lung injury and inflammatory infiltration, reduced the levels of IL-6, IL-1β, and TNF-α, and decreased cell apoptosis as well as the activation of the NLRP3 inflammasome. Besides, in LPS-stimulated Beas-2B cells, both 4µ8C and knockdown of XBP1 diminished the mRNA levels of IL-6 and IL-1B, inhibited cell apoptosis and reduced the protein levels of TXNIP, NLRP3 and secreted IL-1β. Mechanically, the phosphorylation and nuclear translocation of ERK1/2 and p65 were significantly suppressed by 4µ8C and XBP1 knockdown.

CONCLUSIONS

In summary, our findings suggest that IRE1α-XBP1 axis is crucial in the pathogenesis of ALI/ARDS, whose suppression could mitigate the pulmonary inflammatory response and cell apoptosis in ALI through the TXNIP/NLRP3 inflammasome and ERK/p65 signaling pathway. Our study may provide new evidence that IRE1α-XBP1 may be a promising therapeutic target for ALI/ARDS.

Novel Therapeutic Target for ALI/ARDS: Forkhead Box Transcription Factors

ALI/ARDS can be a pulmonary manifestation of a systemic inflammatory response or a result of overexpression of the body's normal inflammatory response involving various effector cells, cytokines, and inflammatory mediators, which regulate the body's immune response through different signalling pathways. Forkhead box transcription factors are evolutionarily conserved transcription factors that play a crucial role in various cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism, and DNA damage response. Transcription factors control protein synthesis by regulating gene transcription levels, resulting in diverse biological outcomes. The Fox family plays a role in activating or inhibiting the expression of various molecules related to ALI/ARDS through phosphorylation, acetylation/deacetylation, and control of multiple signalling pathways. An in-depth analysis of the integrated Fox family's role in ALI/ARDS can aid in the development of potential diagnostic and therapeutic targets for the condition.

Dexmedetomidine promotes necroptosis by upregulating PARP1 in non-small cell lung cancer

The score and prognostic value of necroptosis were analyzed in the TCGA and GSE120622 datasets. Necroptosis has the highest correlation with the immune microenvironment, and the high score in NSCLC correlates with poor prognosis. Differentially expressed genes between non-small cell lung cancer (NSCLC) and controls in both datasets were identified and subjected to construct co-expression networks, respectively. Black and blue modules were selected because of high correction with necroptosis. The intersected two module genes were mainly involved in immune and inflammatory response, cell cycle process and DNA replication. Nine marker genes of necroptosis were identified in these modules and considered as candidate genes. Based on candidate genes, we identified two clusters utilizing concordance clustering, additionally dividing NSCLC samples into high- and low-risk groups. There were significant differences in overall survival between two clusters and between high- and low-risk groups. Furthermore, PARP1 was found among the candidate genes to be the target gene of dexmedetomidine acting on necroptosis. Molecular experimental results found that PARP1 was highly expressed in the dexmedetomidine treated NSCLC compared with the NSCLC. Candidate genes associated with necroptosis may provide a powerful prognostic tool for precision oncology. Dexmedetomidine may target PARP1 to promote necroptosis and then affect NSCLC.

Cilostazol Combats Lipopolysaccharide-Induced Hippocampal Injury in Rats: Role of AKT/GSK3β/CREB Curbing Neuroinflammation

Neuroinflammation is important in the pathophysiology of several degenerative brain disorders. This study looked at the potential neuroprotective benefits of cilostazol, a phosphodiesterase inhibitor, against LPS-induced hippocampus damage in rodents and the principal molecular involvement of AKT/GSK3β/CREB signaling pathways. Behavioral tests revealed that cilostazol successfully corrected LPS-induced neurobehavioral impairments. Furthermore, cilostazol therapy lowered hippocampal levels of amyloid beta 1-42 (Aβ1-42) and p-tau protein, both of which are critical pathological indicators of neurodegenerative disorders. Furthermore, cilostazol administration suppressed LPS-induced rises in hippocampus caspase-3 and NF-κB levels while elevating rat B-cell/lymphoma 2 (BCL2) and brain-derived neurotrophic factor (BDNF) levels, which are implicated in neuronal survival and synaptic plasticity. Cilostazol treatment also restored the decreased phosphorylation of protein kinase B (p-AKT) and reduced the elevated levels of phosphorylated glycogen synthase kinase-3 beta (p-GSK3β) and cAMP response element-binding protein (CREB) in the hippocampus of LPS-treated rats. Histopathological examination revealed that cilostazol ameliorated LPS-induced brain damage with reduced neuronal loss and gliosis. Immunohistochemistry analysis showed a decrease in Iba-1 expression, indicating a reduction in microglial activation in the cilostazol-treated group compared to the LPS group. The findings advocate that cilostazol exerts neuroprotective effects against LPS-induced hippocampal injury by modulating the AKT/GSK3β/CREB pathway and curbing neuroinflammation. Cilostazol may hold promise as a therapeutic agent for neuroinflammatory conditions associated with neurodegenerative diseases.

The long non-coding RNA mir155hg promotes NLRP3-inflammasome activation and oxidative stress response in acute lung injury by targeting miR-450b-5p to regulate HIF-1α

BACKGROUND

Acute lung injury (ALI) can cause multiple organ dysfunction and a high mortality rate. Inflammatory responses, oxidative stress, and immune damage contribute to their pathogenic mechanisms. We studied the role of the newly discovered lncRNA, Lncmir155hg, in ALI.

METHODS

The levels of Lncmir155hg and miR-450b-5p from mice with ALI were detected via polymerase chain reaction analysis (qRT-PCR) and Fluorescence in situ hybridization (FISH). Pathological changes of lung were detected by HE (hematoxylin and eosin) staining, and HIF-1α, NOD-like receptor 3 (NLRP3) and caspase-1 protein changes were detected by immunohistochemistry. MLE-12 cells proliferation was detected by Cell-Counting Kit 8 analysis, and reactive oxygen species (ROS) was detected via flow cytometry. NLRP3, apoptosis-associated speck-like protein (ASC), and caspase-1 were measured via western blotting, and enzyme-linked immunosorbent assays detected the expression of Inflammatory factors. Lncmir155hg, miR-450b-5p, miR-450b-5p, and HIF-1α targets were predicted using LncTar and miRWalk and confirmed in dual-luciferase reporter assays.

RESULTS

In mice with ALI and MLE-12 cells induced by lipopolysaccharide (LPS), Lncmir155hg was high-expressed and miR-450b-5p was low-expressed. sh-Lncmir155hg reduced the damage of lung tissue, the production of inflammatory cytokines and oxidative stress reaction induced by LPS，miR-450b-5p reverses the effect of Lncmir155hg in mice. sh-Lncmir155hg decreased the protein levels of HIF-1α, NLRP3 and caspase-1 in LPS-induced lung tissues. sh-Lncmir155hg + miR-450b-5p inhibitor transfection reversed the effect of sh-Lncmir155hg on the expression of HIF-1α, NLRP3 and caspase-1. Lncmir155hg knockdown induced proliferation and inhibited NLRP3-inflammasome activation and oxidative stress in MLE-12 cells of ALI. miR-450b-5p was identified to have binding with Lncmir155hg, and inhibition of miR-450b-5p eliminated the effect of si-Lncmir155hg in MLE-12 cells of ALI. More importantly, miR-450b-5p was directly combined with HIF-1α, miR-450b-5p mimic promoted proliferation and inhibited activation of inflammasome associated proteins and reaction of oxidative stress, and HIF-1α overexpression abolished these effects.

CONCLUSION

Lncmir155hg aggravated ALI via the miR-450b-5p/HIF-1α axis.

RNA-Seq profiling of circular RNAs in mice with lipopolysaccharide-induced acute lung injury

Acute lung injury (ALI) is a serious illness that develops suddenly, progresses rapidly, has a poor treatment response and a high mortality rate. Studies have found that circular RNAs (circRNA) play a critical role in several diseases, but their role in ALI remains unclear. The aim of this study was to identify circRNAs that are associated with ALI and investigate their potential molecular mechanisms. A comparison of lung circRNA and microRNA expression profiles in mice with ALI and controls was performed by RNA-sequencing. A bioinformatic analysis was conducted to identify differentially expressed (DE) RNAs, to construct competitive endogenous RNA (ceRNA) networks, and to analyze their function and pathways. Then, a protein-protein interaction (PPI) network was generated by the Search Tool for the Retrieval of Interacting Genes database, and hub genes were identified using Cytoscape. Furthermore, a key ceRNA subnetwork was constructed based on these hub genes. Overall, we found 239 DE circRNAs and 42 DE microRNAs in ALI mice compared to controls. Additionally, the molecular mechanism of ALI was further understood by building ceRNA networks based on these DE genes. ALI-induced circRNAs are mostly function in the inflammatory response and metabolic processes. Moreover, DE circRNAs are primarily involved in the nuclear factor (NF)-kappa B and PI3K-Akt signaling pathways. Seven hub genes were derived from the PPI network of 191 genes, followed by the construction of circRNA-miRNA-hub gene subnetworks. In this study, circRNA profiles are remarkably changed in mice with LPS-triggered ALI, and their potential contribution to the disease is revealed.

Protective Effects and Mechanisms of Luteolin against Acute Respiratory Distress Syndrome: Network Pharmacology and In vivo and In vitro Studies

BACKGROUND

Acute Respiratory Distress Syndrome (ARDS) is an acute life-threatening disease, and luteolin has the potential to become a therapeutic agent for ARDS. However, its mechanism of action has not yet been clarified.

OBJECTIVE

The present study explored the potential effects and mechanisms of luteolin in the treatment of ARDS through network pharmacology analysis and verified them through biological experiments.

METHODS

The potential targets of luteolin and ARDS were obtained from online databases. Functional enrichment and protein-protein interaction (PPI) analyses were performed to explore the underlying molecular mechanisms and to identify hub targets. Molecular docking was used to verify the relationship between luteolin and target proteins. Finally, the effects of luteolin on key signaling pathways and biological processes were verified by in vitro and in vivo experiments.

RESULTS

A total of 146 luteolin- and 496 ARDS-related targets were extracted from public databases. The network pharmacological analysis suggested that luteolin could inhibit ARDS through the following potential therapeutic targets: AKT1, RELA, and NFKBIA. Inflammatory and oxidative stress responses were the main biological processes involved, with the AKT/NF-κB signaling pathway being the key signaling pathway targeted by luteolin for the treatment of ARDS. Molecular docking analysis indicated that luteolin had a good binding affinity to AKT1, RELA, and NFKBIA. The in vitro and in vivo experiments revealed that luteolin could regulate the inflammatory response and oxidative stress in the treatment of ARDS by inhibiting the AKT/NF- κB signaling pathway.

CONCLUSION

Luteolin could reduce the production of reactive oxygen species and inflammatory factors by inhibiting the AKT/NF-κB signaling pathway, thus reducing apoptosis and attenuating ARDS.

Flavone attenuates nicotine-induced lung injury in rats exposed to gamma radiation via modulating PI3K/Nrf2 and FoxO1/NLRP3 inflammasome

Prolonged exposure to different occupational or environmental toxicants triggered oxidative stress and inflammatory reactions mediated lung damage. This study was designed to explore the influence and protective impact of flavone on lung injury in rats intoxicated with nicotine (NIC) and exposed to radiation (IR). Forty rats were divided into four groups; group I control, group II flavone; rats were administered with flavone (25 mg/kg/day), group III NIC + IR; rats were injected intraperitoneally with NIC (1 mg/kg/day) and exposed to γ-IR (3.5 Gy once/week for 2 weeks) while group IV NIC + IR + flavone; rats were injected with NIC, exposed to IR and administered with flavone. Redox status parameters and histopathological changes in lung tissue were evaluated. Nuclear factor-kappa B (NF-κB), forkhead box O-class1 (FoxO1) and nucleotide-binding domain- (NOD-) like receptor pyrin domain-containing-3 (NLRP3) gene expression were measured in lung tissues. Moreover, nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and phosphatidylinositol three kinase (PI3K) were measured using ELISA kits. Our data demonstrates, for the first time, that flavone protects the lung from NIC/IR-associated cytotoxicity, by attenuating the disrupted redox status and aggravating the antioxidant defence mechanism via activation of the PI3K/Nrf2. Moreover, flavone alleviates pulmonary inflammation by inhibiting the inflammatory signaling pathway FOXO1/NF-κB/NLRP3- Inflammasome. Collectively, the obtained results exhibited a notable efficiency of flavone in alleviating lung injury induced by NIC and IR via modulating PI3K/Nrf2 and FoxO1/NLRP3 Inflammasome.

IRE1α/XBP-1 promotes β-catenin signaling activation of airway epithelium in lipopolysaccharide-induced acute lung injury

BACKGROUND

Acute lung injury (ALI), along with the more severe condition--acute respiratory distress syndrome (ARDS), is a major cause of respiratory failure in critically ill patients with high morbidity and mortality. Inositol-requiring protein 1α (IRE1α)/X box protein-1 (XBP1) pathway was proved to regulate lipopolysaccharide (LPS)-induced lung injury and inflammation. Yet, its role on epithelial β-catenin in LPS-induced ALI remains to be elucidated.

METHODS

LPS-induced models were generated in mice (5 mg/kg) and Beas-2B cells (200 μg/mL). Two selective antagonists of IRE1α (4μ8c and STF-083010) were respectively given to LPS-exposed mice and cultured cells.

RESULTS

Up-regulated expression of endoplasmic reticulum (ER) stress markers immunoglobulin-binding protein (BIP) and spliced X box protein-1(XBP-1s) was detected after LPS exposure. Besides, LPS also led to a down-regulated total β-catenin level in the lung and Beas-2B cells, with decreased membrane distribution as well as increased cytoplasmic and nuclear accumulation, paralleled by extensively up-regulated downstream targets of the Wnt/β-catenin signaling. Treatment with either 4μ8c or STF-083010 not only significantly attenuated LPS-induced lung injury and inflammation, but also recovered β-catenin expression in airway epithelia, preserving the adhesive function of β-catenin while blunting its signaling activity.

CONCLUSION

These results illustrated that IRE1α/XBP1 pathway promoted the activation of airway epithelial β-catenin signaling in LPS-induced ALI.

Diosmetin induces apoptosis and protective autophagy in human gastric cancer HGC-27 cells via the PI3K/Akt/FoxO1 and MAPK/JNK pathways

Gastric cancer represents a significant global health concern, necessitating the exploration of novel therapeutic options. Diosmetin, a natural flavonoid derived from citrus and vegetables, has demonstrated promising anti-tumor activity against various tumor cells. However, the potential anticancer effect of diosmetin in gastric cancer and its underlying mechanism have yet to be elucidated. In this study, we aimed to investigate the impact of diosmetin on cell proliferation, migration, cell cycle progression and apoptosis in human gastric cancer HGC-27 cells. Our findings revealed that diosmetin effectively suppressed cell proliferation, induced G2/M phase cell cycle arrest, and triggered cell apoptosis. Mechanistically, diosmetin downregulated the expression of antiapoptotic proteins Bcl-2 and Bcl-xL, while upregulated the level of proapoptotic proteins such as Bax, cleaved PARP and cleaved caspase-3. Additionally, diosmetin inhibited Akt and FoxO1 phosphorylation, while activated the MAPK signaling pathway. Notably, pretreatment of IGF-1, an Akt activator, attenuated the diosmetin-induced apoptosis. Furthermore, pretreatment with SP600125, a JNK inhibitor, significantly reduced the protein level of LC3B, while promoted the expression of cleaved caspase-3 and cleaved PARP. Collectively, our results suggest that diosmetin holds promise as an effective therapeutic agent against gastric cancer by inducing apoptosis through inhibition of the Akt/FoxO1 pathway and promoting protective autophagy via the MAPK/JNK signaling pathway.

Potential tactics with vitamin D and certain phytochemicals for enhancing the effectiveness of immune-checkpoint blockade therapies

Immunotherapy strategies targeting immune checkpoint molecules such as programmed cell death-1 (PD-1) and cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) are revolutionizing oncology. However, its effectiveness is limited in part due to the loss of effector cytotoxic T lymphocytes. Interestingly, supplementation of vitamin D could abolish the repressive effect of programmed cell death-ligand 1 (PD-L1) on CD8⁺ T cells, which might prevent the lymphocytopenia. In addition, vitamin D signaling could contribute to the differentiation of T-regulatory (Treg) cells associated with the expression of Treg markers such as forkhead box P3 (FOXP3) and CTLA-4. Furthermore, vitamin D may be associated with the stimulation of innate immunity. Peroxisome proliferator-activated receptor (PPAR) and estrogen receptor (ESR) signaling, and even the signaling from phosphoinositide-3 kinase (PI3K)/AKT pathway could have inhibitory roles in carcinogenesis possibly via the modulation of immune checkpoint molecules. In some cases, certain small molecules including vitamin D could be a novel therapeutic modality with a promising potential for the better performance of immune checkpoint blockade cancer therapies.

HDAC3 deficiency protects against acute lung injury by maintaining epithelial barrier integrity through preserving mitochondrial quality control

Sepsis is one common cause of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), which is closely associated with high mortality in intensive care units (ICU). Histone deacetylase 3 (HDAC3) serves as an important epigenetic modifying enzyme which could affect chromatin structure and transcriptional regulation. Here, we explored the effects of HDAC3 in type II alveolar epithelial cells (AT2) on lipopolysaccharide (LPS)-induced ALI and shed light on potential molecular mechanisms. We generated ALI mouse model with HDAC3 conditional knockout mice (Sftpc-cre; Hdac3^f/f) in AT2 and the roles of HDAC3 in ALI and epithelial barrier integrity were investigated in LPS-treated AT2. The levels of HDAC3 were significantly upregulated in lung tissues from mice with sepsis and in LPS-treated AT2. HDAC3 deficiency in AT2 not only decreased inflammation, apoptosis, and oxidative stress, but also maintained epithelial barrier integrity. Meanwhile, HDAC3 deficiency in LPS-treated AT2 preserved mitochondrial quality control (MQC), evidenced by the shift of mitochondria from fission into fusion, decreased mitophagy, and improved fatty acid oxidation (FAO). Mechanically, HDAC3 promoted the transcription of Rho-associated protein kinase 1 (ROCK1) in AT2. In the context of LPS stimulation, the upregulated ROCK1 elicited by HDAC3 could be phosphorylated by Rho-associated (RhoA), thus disturbing MQC and triggering ALI. Furthermore, we found that forkhead box O1 (FOXO1) was one of transcription factors of ROCK1. HDAC3 directly decreased the acetylation of FOXO1 and promoted its nuclear translocation in LPS-treated AT2. Finally, HDAC3 inhibitor RGFP966 alleviated epithelial damage and improved MQC in LPS-treated AT2. Altogether, HDAC3 deficiency in AT2 alleviated sepsis-induced ALI by preserving mitochondrial quality control via FOXO1-ROCK1 axis, which provided a potential strategy for the treatment of sepsis and ALI.

The potential mechanism of the Ruhao Dashi formula in treating acute pneumonia via network pharmacology and molecular docking

BACKGROUND

Acute pneumonia (AP) has a high seasonal prevalence every year, which seriously threatens the lives and health of patients. Six traditional Chinese medicines in Ruhao Dashi formula (RDF) have excellent antiinflammatory, antibacterial, and antiviral effects. RDF is commonly used in the clinical treatment of AP. However, the mechanism and target of RDF are unclear. Therefore, this study aimed to use network pharmacology and molecular docking to evaluate the target and mechanism of RDF in the treatment of AP.

METHODS

The Herbs and Disease Gene databases were searched to identify common targets of AP and RDF. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and Protein-Protein Interaction (PPI) network analyses were performed to identify the potential molecular mechanisms behind RDF. Molecular docking was performed to compare the binding activities of the active molecules with that of the target protein.

RESULTS

The "drug-component-common target" network contained 64 active compounds and 134 targets. GO and KEGG analyses indicated that RDF could act by regulating cell death, cell proliferation, apoptosis, and hypoxic response. The PPI network and "pathway-target" network identified 31 core targets. Molecular docking revealed that the 14 active ingredients of RDF bind vigorously to the core targets.

CONCLUSION

Through network pharmacology and molecular docking, we found that RDF contains 14 active components and 31 core AP targets. These targets were linked to the development of an antiinflammatory response and could be used to develop new drugs to treat AP.

BAP31 regulates the expression of ICAM-1/VCAM-1 via MyD88/NF-κB pathway in acute lung injury mice model

AIMS

The cell adhesion molecules (CAMs) that mediate neutrophil-endothelium cell adhesion are deeply involved in the pathogenesis of acute lung injury (ALI). B-cell receptor associated protein 31 (BAP31) has been reported to engage in the expression of some CAMs. This study was undertaken to explore whether BAP31 in endotheliocyte affects the pathological process of ALI by regulating CAMs, and its possible mechanism.

MAIN METHODS

Our study used the shBAP31 endothelium cell lines and endothelial-specific BAP31 conditional knockdown mice constructed via Cre/loxP system. Hematoxylin and eosin staining was used to observe the histopathological manifestations. The adhesion of neutrophils to vascular wall was examined by intravital microscopy. The nuclear translocation of NF-κB was observed by immunofluorescence staining assay. Flow cytometric, real-time polymerase chain reaction and Western blot assay were performed to determine the expression of CAMs and key proteins in MyD88/NF-κB-related signaling pathway. Luciferase reporter and chromatin immunoprecipitation assay were analyzed for transcriptional activity of ICAM-1 and VCAM-1.

KEY FINDINGS

Mechanistic investigations indicated that endothelium-specific BAP31 depletion dramatically reduced the capacity of neutrophils adherence to endothelial cells (ECs), which was mainly attributed to the significant downregulation of ICAM-1 (p < 0.05) and VCAM-1 (p < 0.05) expression. Interestingly, BAP31 knockdown apparently deactivated MyD88/TRAF6-mediated TAK1/NF-κB and PI3K/Akt signaling cascades, resulting in the inhibition of NF-κB activation and nuclear translocation.

SIGNIFICANCE

Our data furnished convincing evidence that BAP31 deficiency performs a mitigative effect on ALI by decreasing neutrophils-ECs adhesion. These findings identified BAP31 as a promising protein for regulating the pathogenesis process of ALI.

Anti-Inflammatory Effects of Polyphenols from Plum (Prunus salicina Lindl) on RAW264.7 Macrophages Induced by Monosodium Urate and Potential Mechanisms

Acute gouty arthritis is an acute inflammatory reaction caused by the deposition of monosodium urate (MSU) crystals in joints and surrounding soft tissues. Controlling inflammation is the key to preventing acute gouty arthritis. Anti-inflammatory activities and the possible molecular mechanisms of plum (Prunus salicina Lindl cv. "furong") polyphenols (PSLP) on RAW264.7 macrophage cells induced by monosodium urate were investigated. PPSF significantly inhibited the activity of inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-18 (IL-18). In addition, PPSF exhibited excellent activation of superoxide dismutase (SOD) activity and reduction of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) levels in RAW264.7 macrophages. The results of global screening of all transcripts by RNA-seq revealed 8585 differentially expressed genes between the PSLP-treated group and the MUS group. From GO analysis, PSLP could affect the occurrence and development of RAW264.7 macrophage inflammation through biological processes, such as organic substance metabolism, intracellular organelles, and binding function. The regulation mechanism of PSLP on MSU-induced RAW264.7 macrophage inflammation may be achieved through the HIF-1 signaling pathway, renal cell carcinoma, the ErbB signaling pathway, and the FoxO signaling pathway. Therefore, PSLP has great prospects in the prevention of gout and similar inflammatory diseases.

Attenuation of the Severity of Acute Respiratory Distress Syndrome by Pomiferin through Blocking Inflammation and Oxidative Stress in an AKT/Foxo1 Pathway-Dependent Manner

Acute respiratory distress syndrome (ARDS) gives rise to uncontrolled inflammatory response and oxidative stress, causing very high mortality globally. Pomiferin is a kind of prenylated isoflavonoid extracted from Maclura pomifera, owning anti-inflammatory and antioxidant properties. However, the functions and possible mechanisms of pomiferin in lipopolysaccharide- (LPS-) induced ARDS remain unknown. C57BL/6 mice were injected with LPS (5 mg/kg) intratracheally to induce an in vivo ARDS model while RAW264.7 macrophages were stimulated with LPS (100 ng/ml) to induce an in vitro model. Our data demonstrated that pomiferin (20 mg/kg) significantly improved pulmonary function and lung pathological injury in mice with ARDS, apart from increasing survival rate. Meanwhile, pomiferin treatment also inhibited LPS-induced inflammation as well as oxidative stress in lung tissues. LPS stimulation significantly activated AKT/Foxo1 signal pathway in lung tissues, which could be reversed after pomiferin treatment. In vitro experiments further showed that 10, 20, and 50 μM of pomiferin could enhance cell viability of RAW264.7 macrophages stimulated with LPS. What is more, 3-deoxysappanchalcone (3-DE), one AKT agonist, was used to active AKT in RAW264.7 macrophages. The results further showed that 3-DE could abolish pomiferin-elicited protection in LPS-treated RAW264.7 macrophages, evidenced by activated inflammation and oxidative stress. Taken together, our study showed that pomiferin could exert an ARDS-protective effect by blocking the AKT/Foxo1 signal pathway to inhibit LPS-induced inflammatory response and oxidative injury, which may serve as a potential candidate for the treatment of ARDS in the future.

Avanafil as a Novel Therapeutic Agent Against LPS-Induced Acute Lung Injury via Increasing CGMP to Downregulate the TLR4-NF-κB-NLRP3 Inflammasome Signaling Pathway

AIM

We demonstrate the effect of PDE5 inhibitors in cases of acute lung injury via the relationship between cGMP/NO and the TLR4-NF-κB-NLRP3 pathway.

MATERIALS AND METHODS

This study was performed with 30 male Wistar albino rats. Lipopolysaccharide (LPS) was administered intratracheally to the rats and acute lung injury (ALI) was induced. Twelve hours after LPS administration, avanafil, prepared at suitable doses according to the body weights of the animals, was administered by oral gavage. Lung tissue samples of all groups were examined histopathologically and by immunochemical staining (IL-1β, iNOS, TLR4, and NF-κB). The iNOS, NLRP3, and IL-1B mRNA expression levels in the lung tissues were measured by RT-PCR. The left upper lobes of the rat lungs were dried at 70 °C for 48 h and lung water content was calculated.

RESULT

Statistically significant increases in iNOS, NLRP3, and IL-1β mRNA expressions were observed in the rats with ALI compared to the healthy controls (p < 0.0001). Those increased expressions were reduced at both doses of avanafil (p < 0.0001). This reduction was found to be greater at 20 mg/kg (p < 0.0001). IL-1β, iNOS, TLR4, and NF-κB immunopositivity was moderate/severe in the ALI group and mild in the group with ALI + avanafil at 20 mg/kg (p < 0.05). When the wet/dry lung ratios were calculated, a statistically significant increase was seen in the ALI group compared to the healthy rats (p < 0.05). That increase was decreased with both avanafil doses (p < 0.05).

CONCLUSION

We suggest that avanafil may prevent the progression of ALI and be effective in its treatment. We hope that this study will be supported by future clinical studies to yield a new indication for avanafil.

Dexmedetomidine Attenuates LPS-Stimulated Alveolar Type II Cells’ Injury through Upregulation of miR-140-3p and Partial Suppression of PD-L1 Involving Inactivating JNK-Bnip3 Pathway

Dexmedetomidine (DEX), which is reported to be a newly discovered, novel α-2 adrenoceptor agonist, is known to exhibit anti-inflammatory properties in several diseases. DEX regulates inflammation-related signaling pathways and genes through interactions with several miRNAs. This study verified that expression levels of miR-140-3p were diminished when alveolar type II cells were exposed to LPS. However, the levels of miR-140-3p were confirmed as showing an increase with DEX treatment. These observations revealed that the expression of miR-140-3p was related to the beneficial effects that accompanied the DEX treatment of LPS-induced ALI. In addition, PD-1/PD-L1 expression increased extensively when RLE-6TN cells were induced by LPS. The increased expression was reduced after treatment with DEX. Thus, it appears that the PD-L1 expression was targeted directly by miR-140-3p, resulting in the partial repression of PD-L1 levels, which involved the inhibition of p-JNK and Bnip3 expression. Therefore, DEX was shown to inhibit the PD-L1 expression by promoting partially increased miR-140-3p levels in RLE-6TN cells. DEX also inactivated the JNK-Bnip3 pathway, resulting in the inhibition of inflammation and alleviating alveolar type II cell injury.

Dexmedetomidine protects against acute lung injury in mice via the DUSP1/MAPK/NF-κB axis by inhibiting miR-152-3p

OBJECTIVE

Acute lung injury (ALI) is a debilitating condition in clinics. Dexmedetomidine (Dex) is known for its anti-apoptotic and anti-inflammatory properties. This study attempted to investigate the protective mechanism of Dex in ALI mice.

METHODS

Mice were pretreated with Dex before model establishment by tracheal injection of lipopolysaccharide (LPS). Pulmonary function indexes and wet-to-dry (W/D) ratio were measured. Pulmonary pathological changes were observed through HE staining, CD31+-positive mouse pulmonary microvascular endothelial cells (MPMVECs) were counted through immunofluorescence staining, and apoptosis was detected through TUNEL staining. miR-152-3p mimic, sh-DUSP1, or p38 MAPK inhibitor was delivered into MPMVECs, followed by combined treatment of Dex and LPS. miR-152-3p expression, apoptosis, levels of apoptosis- and MAPK/NF-κB pathway-associated proteins, and inflammatory factors were measured through RT-qPCR, flow cytometry, Western blot, and ELISA. The binding relationship of miR-152-3p and DUSP1 was verified through bioinformatics software and dual-luciferase assay. ALI mouse model was established after injection of miR-152-3p antagomir.

RESULTS

Dex improved ALI mouse pulmonary function and mitigated injury in mice and MPMVECs. miR-125-3p overexpression or sh-DUSP1 partially abolished the protection of Dex on MPMVECs. miR-152-3p targeted DUSP1. sh-DUSP1 partially averted the protection of Dex on MPMVECs. Dex inhibited the activation of the MAPK/NF-κB pathway in MPMVECs mediated by LPS, which was partially reversed by sh-DUSP1. The p38 MAPK inhibitor SB203580 antagonized the protective effect of Dex on MPMVECs mediated by sh-DUSP1. Similarly, downregulation of miR-152-3p mitigated ALI via the DUSP1/MAPK/NF-κB axis in vivo.

CONCLUSION

Dex relieved ALI in mice via the DUSP1/MAPK/NF-κB axis by down-regulating miR-152-3p.

Exploration of the Function of Ginsenoside RD Attenuates Lipopolysaccharide-Induced Lung Injury: A Study of Network Pharmacology and Experimental Validation

OBJECTIVE

Ginsenoside Rd (GSRd) displays a variety of pharmacological effects. However, the underlying role in acute lung injury (ALI) is not clear. In this study, the protective effect of GSRd on lipopolysaccharide (LPS)-induced ALI is investigated to explore the potential mechanisms.

METHODS

GSRd-target-ALI-related gene set was constructed. And bioinformatics tools were used to discover the potential mechanism. We observed the survival of subjects for 72 h. In addition, male BALB/c mice were intraperitoneal injected with GSRd (25 and 50 mg/kg) after received one intratracheal instillation of LPS. Inflammatory changes, oxidative stress, and phosphorylation were assessed to study the biological effects.

RESULTS

A total of 245 interaction genes were collected. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were enriched in immune-inflammatory system. Among them, PI3K-Akt signaling pathway was the highest-ranked pathway of inflammatory response. In vivo study, it was found that GSRd improved survival in endotoxemic mice and inhibited the major characteristic of ALI. And the p-PI3K and p-Akt expression was significantly decreased by GSRd treatment.

CONCLUSION

GSRd could protect mice against LPS-induced ALI effectively by inhibiting the PI3K-Akt signaling pathway.