Protective Effect of Fluorofenidone Against Acute Lung Injury Through Suppressing the MAPK/NF-κB Pathway

AFK-PD alleviated osteoarthritis progression by chondroprotective and anti-inflammatory activity

Osteoarthritis (OA) is the most prevalent cartilage degenerative and low-grade inflammatory disease of the whole joint. However, there are currently no FDA-approved drugs or global regulatory agency-approved treatments OA disease modification. Therefore, it's essential to explore novel effective therapeutic strategies for OA. In our study, we investigated the effects of AFK-PD, a novel pyridone agent, on the development of OA induced by destabilization of the medial meniscus (DMM) in vivo, and its impact on the function of chondrocytes treated with IL-1β in vitro. Our results demonstrated AFK-PD alleviated OA progression through inhibiting cartilage degeneration, articular inflammation and osteophyte formation. Notably, AFK-PD inhibited chondrocyte inflammation and synovial macrophage M1 polarization, leading to the attenuation of articular inflammation. Additionally, AFK-PD promoted chondrocyte anabolism while mitigating catabolism and apoptosis, effectively inhibiting cartilage degeneration. Mechanistically, AFK-PD suppressed the expression of key signaling molecules involved in the MAPK pathway, such as p-ERK1/2 and p-JNK, as well as the NF-κB signaling molecule p-p65, in IL-1β-induced chondrocytes. These findings suggest AFK-PD ameliorates the development of OA by protecting chondrocyte functions and inhibiting articular inflammation in chondrocytes and synovial macrophages. Overall, our study highlights AFK-PD as a promising therapeutic candidate for the treatment of OA.

Urolithin A exerts a protective effect on lipopolysaccharide-induced acute lung injury by regulating HMGB1-mediated MAPK and NF-κB signaling pathways

Acute lung injury (ALI) is a severe inflammatory disorder that has a high morbidity and mortality rate. Urolithin A (UA) is reported to have anti-inflammatory and anti-oxidative effects in ALI. However, its molecular mechanisms in ALI remain to be explored. Mice and BEAS-2B cells were administrated with lipopolysaccharide (LPS) to mimic the ALI model in vivo and in vitro. Hematoxylin-eosin (HE) staining was used to detect the pathological injury of lung tissues. The levels of proinflammatory cytokines in bronchoalveolar lavage fluid (BALF) and culture supernatant and the levels of oxidative stress markers in lung tissues were measured using ELISA. DCFH-DA probe was used to assess the reactive oxygen species (ROS) level. TUNEL staining and flow cytometry were performed to determine cell apoptosis. The key targets and pathways were confirmed by immunohistochemistry (IHC) and western blot. UA suppressed the pathologic damage, wet/dry weight ratio, and total protein and inflammatory cells in BALF. UA decreased neutrophil infiltration and proinflammatory cytokines production. UA reduced the level of malondialdehyde (MDA) and increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in pulmonary tissues. UA also inhibited cell apoptosis in lung tissues by decreasing Bax expression and increasing Bcl-2 expression. In addition, UA suppressed LPS-induced inflammatory factor production, ROS level, and cell apoptosis in BEAS-2B. Importantly, UA decreased the expression of HMGB1 in LPS-treated mice and BEAS-2B cells. HMGB1 overexpression greatly abrogated the inhibition of UA on inflammation, ROS, and cell apoptosis in LPS-administrated BEAS-2B. Furthermore, UA treatment suppressed the phosphorylated levels of p38, JNK, ERK, and p65 in LPS-administrated mice and BEAS-2B cells. UA alleviated lung inflammation, oxidative stress, and apoptosis in ALI by targeting HMGB1 to inactivate the MAPK/NF-κB signaling, suggesting the potential of UA to treat ALI.

Exploring immune-related pathogenesis in lung injury: Providing new insights Into ALI/ARDS

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) represent a significant global burden of morbidity and mortality, with lung injury being the primary cause of death in affected patients. The pathogenesis of lung injury, however, remains a complex issue. In recent years, the role of the immune system in lung injury has attracted extensive attention worldwide. Despite advancements in our understanding of various lung injury subtypes, significant limitations persist in both prevention and treatment. This review investigates the immunopathogenesis of ALI/ARDS, aiming to elucidate the pathological processes of lung injury mediated by dendritic cells (DCs), natural killer (NK) cells, phagocytes, and neutrophils. Furthermore, the article expounds on the critical contributions of gut microbiota, inflammatory pathways, and cytokine storms in the development of ALI/ARDS.

6-Gingerol via overexpression of miR-322-5p impede lipopolysaccharide-caused inflammatory response in RAW264.7 cells

Acute lung injury (ALI) and sepsis are complicated syndromes that are often left untreated in critically ill patients. 6-Gingerol is a phenolic phytochemical compound that is found in fresh ginger, has pharmacological effects against inflammation. This study explored the roles of 6-gingerol in a mouse model of acute lung injury caused by lipopolysaccharide (LPS) and RAW-264.7 cells inflammation. The LPS-induced animal model underwent histopathological examinations, and RAW-264.7 cells viability was determined by Cell counting Kit-8 (CCk-8) assay. Additionally, qRT-PCR, Immunofluorescence, Western blot, and ELISA were used in vivo and in vitro to identify inflammatory factors and proteins associated with NF-κB and MAPK signaling pathways. In a histological examination 6-gingerol exhibited protective effects. Moreover, 6-gingerol elevated cell viability and downregulated inflammatory factors Interlukin-1β (IL-1β), Interlukin-6 (IL-6) and Tumor necrosis factor-α (TNF-α) in LPS-treated RAW-264.7 cells. Furthermore, 6-gingerol decreased phosphorylation of P65, P38 and the level of JNK in NF-κB and MAPK pathways. Importantly, 6-gingerol increased transcript abundance of miR-322-5p which suppressed by LPS and miR-322-5p downregulation negated the protective functions of 6-gingerol. The protective activity of 6-gingerol was mediated by miR-322-5p up-regulation.

Current investigations for liver fibrosis treatment: between repurposing the FDA-approved drugs and the other emerging approaches

Long-term liver injuries lead to hepatic fibrosis, often progressing into cirrhosis, liver failure, portal hypertension, and hepatocellular carcinoma. There is currently no effective therapy available for liver fibrosis. Thus, continuous investigations for anti-fibrotic therapy are ongoing. The main theme of anti-fibrotic investigation during recent years is the rationale-based selection of treatment molecules according to the current understanding of the pathology of the disease. The research efforts are mainly toward repurposing current FDA-approved drugs targeting etiological molecular factors involved in developing liver fibrosis. In parallel, investigations also focus on experimental small molecules with evidence to hinder or reverse the fibrosis. Natural compounds, immunological, and genetic approaches have shown significant encouraging effects. This review summarizes the efficacy and safety of current under-investigation antifibrosis medications targeting various molecular targets, as well as the properties of antifibrosis medications, mainly in phase II and III clinical trials.

Metabolomic profiling combined with network analysis of serum pharmacochemistry to reveal the therapeutic mechanism of Ardisiae Japonicae Herba against acute lung injury

Introduction: Acute lung injury (ALI) is a common and devastating respiratory disease associated with uncontrolled inflammatory response and transepithelial neutrophil migration. In recent years, a growing number of studies have found that Ardisiae Japonicae Herba (AJH) has a favorable anti-inflammatory effect. However, its serum material basis and molecular mechanism are still unknown in ALI treatment. In this study, metabolomics and network analysis of serum pharmacochemistry were used to explore the therapeutic effect and molecular mechanism of AJH against lipopolysaccharide (LPS)-induced ALI. Methods: A total of 12 rats for serum pharmacochemistry analysis were randomly divided into the LPS group and LPS + AJH-treated group (treated with AJH extract 20 g/kg/d), which were administered LPS (2 mg/kg) by intratracheal instillation and then continuously administered for 7 days. Moreover, 36 rats for metabolomic research were divided into control, LPS, LPS + AJH-treated (5, 10, and 20 g/kg/d), and LPS + dexamethasone (Dex) (2.3 × 10-4 g/kg/d) groups. After 1 h of the seventh administration, the LPS, LPS + AJH-treated, and LPS + Dex groups were administered LPS by intratracheal instillation to induce ALI. The serum pharmacochemistry profiling was performed by UPLC-Orbitrap Fusion MS to identify serum components, which further explore the molecular mechanism of AJH against ALI by network analysis. Meanwhile, metabolomics was used to select the potential biomarkers and related metabolic pathways and to analyze the therapeutic mechanism of AJH against ALI. Results: The results showed that 71 serum components and 18 related metabolites were identified in ALI rat serum. We found that 81 overlapping targets were frequently involved in AGE-RAGE, PI3K-AKT, and JAK-STAT signaling pathways in network analysis. The LPS + AJH-treated groups exerted protective effects against ALI by reducing the infiltration of inflammatory cells and achieved anti-inflammatory efficacy by significantly regulating the interleukin (IL)-6 and IL-10 levels. Metabolomics analysis shows that the therapeutic effect of AJH on ALI involves 43 potential biomarkers and 14 metabolic pathways, especially phenylalanine, tyrosine, and tryptophan biosynthesis and linoleic acid metabolism pathways, to be influenced, which implied the potential mechanism of AJH in ALI treatment. Discussion: Our study initially elucidated the material basis and effective mechanism of AJH against ALI, which provided a solid basis for AJH application.

Fluorofenidone protects against acute liver failure in mice by regulating MKK4/JNK pathway

AIMS

Acute liver failure (ALF) is a life-threatening disease characterized by abrupt and extensive hepatic necrosis and apoptosis, resulting in high mortality. The approved drug, N-acetylcysteine (NAC), is only effective for acetaminophen (APAP)-associated ALF at the early stage. Thus, we investigate whether fluorofenidone (AKF-PD), a novel antifibrosis pyridone agent, protects against ALF in mice and explore its underlying mechanisms.

METHODS

ALF mouse models were established using APAP or lipopolysaccharide/D-galactosamine (LPS/D-Gal). Anisomycin and SP600125 were used as JNK activator and inhibitor, respectively, and NAC served as a positive control. Mouse hepatic cell line AML12 and primary mouse hepatocytes were used for in vitro studies.

RESULTS

AKF-PD pretreatment alleviated APAP-induced ALF with decreased necrosis, apoptosis, reactive oxygen species (ROS) markers, and mitochondrial permeability transition in liver. Additionally, AKF-PD alleviated mitochondrial ROS stimulated by APAP in AML12 cells. RNA-sequencing in the liver and subsequent gene set enrichment analysis showed that AKF-PD significantly impacted MAPK and IL-17 pathway. In vitro and in vivo studies demonstrated that AKF-PD inhibited APAP-induced phosphorylation of MKK4/JNK, while SP600125 only inhibited JNK phosphorylation. The protective effect of AKF-PD was abolished by anisomycin. Similarly, AKF-PD pretreatment abolished hepatotoxicity caused by LPS/D-Gal, decreased ROS levels, and diminished inflammation. Furthermore, unlike NAC, AKF-PD, inhibited the phosphorylation of MKK4 and JNK upon pretreatment, and improved survival in cases of LPS/D-Gal-induced mortality with delayed dosing.

CONCLUSIONS

In summary, AKF-PD can protect against ALF caused by APAP or LPS/D-Gal, in part, via regulating MKK4/JNK pathway. AKF-PD might be a novel candidate drug for ALF.

Downregulation of ROR2 attenuates LPS-induced A549 cell injury through JNK and ERK signaling pathways

BACKGROUND

We aimed to determine whether receptor tyrosine kinase-like orphan receptor 2 (ROR2) is involved in the occurrence of acute lung injury (ALI) by an animal study and explore the effect of ROR2 downregulation on lipopolysaccharide (LPS)-treated human lung carcinoma A549 cells by a cytological study.

METHODS

Murine models of ALI were successfully constructed by intratracheal instillation of LPS. Meanwhile, A549 cell line stimulated with LPS was used for a cytological study. The expression of ROR2 and its effect on proliferation, cell cycle, apoptosis, and inflammation were detected.

RESULTS

It was found that LPS administration markedly inhibited the cell proliferation, resulted in cell cycle arrest at G1 phage, elevated levels of pro-inflammatory cytokines and apoptosis rate of A549 cells. However, LPS-mediated adverse effects mentioned above were significantly ameliorated by downregulation of ROR2 in comparison with LPS treatment. In addition, administration of ROR2 siRNA notably decreased the phosphorylation level of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) in LPS-challenged A549 cells.

CONCLUSIONS

Thus, the present data indicate that downregulation of ROR2 may decrease LPS-induced inflammatory responses and cell apoptosis through inhibiting JNK and ERK signaling pathway, which attenuates ALI.

Irigenin attenuates lipopolysaccharide-induced acute lung injury by inactivating the mitogen-activated protein kinase (MAPK) signaling pathway

Acute lung injury (ALI) is a serious pulmonary inflammation disease with high mortality. Irigenin, an isoflavone from rhizomes of the Belamcanda chinensis, has been reported to exert anti-inflammatory, anti-oxidative, and anti-apoptotic activities in several diseases. However, it is still unclear whether irigenin can exert a beneficial effect in ALI. A network pharmacology method was utilized to predict the hub targets and potential therapeutic mechanisms of irigenin against ALI. Lipopolysaccharide (LPS) was used to establish the mice model of ALI for evaluating the effects of irigenin. According to the protein-protein interaction (PPI) network, we identified EGFR, HRAS, AKT1, SRC, and HSP90AA1 as the top five significant genes. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment assays showed that irigenin might affect inflammatory response, cytokine production, and cell death by the mitogen-activated protein kinase (MAPK) signaling pathway. In vivo experiment results manifested that irigenin decreased pathological changes, lung Wet/Dry weight ratio, and total protein content in bronchoalveolar lavage fluid (BALF). Irigenin also reduced the production of inflammatory cytokines, including tumor necrosis factor-a (TNF-a), interleukin-1β (IL-1β), interleukin-6 (IL-6), and interleukin-18 (IL-18), and neutrophil infiltration. Additionally, irigenin inhibited pulmonary apoptosis in LPS-treated ALI mice. Moreover, LPS-induced phosphorylation of p38, JNK, and ERK was significantly abated due to the treatment of irigenin. In summary, irigenin ameliorates LPS-induced ALI by suppressing pulmonary inflammation and apoptosis via inactivation of the MAPK signaling pathway. These findings indicated the therapeutic potential of irigenin in ALI.

Mefunidone ameliorates lipopolysaccharide-induced acute lung injury through inhibiting MAPK signaling pathway and enhancing Nrf2 pathway

BACKGROUND AND OBJECTIVE

Acute lung injury (ALI) is a life-threatening disease which has high mortality and lacks effective pharmacological treatments. Excessive inflammation and oxidative stress are the key pathogenesis of ALI. Mefunidone (MFD), a novel small molecule compound, displayed anti-inflammation and anti-oxidative stress effects on streptozocin (STZ) and db/db mice in our previous studies. In this study, we aimed to investigate the effects of MFD on lipopolysaccharide (LPS)-induced ALI and explore the potential molecular mechanisms.

METHODS

We investigated the effects of MFD on LPS-induced ALI mouse model and LPS-stimulated immortalized mouse bone marrow-derived macrophages (iBMDMs).

RESULTS

MFD could alleviate pulmonary structure disorder and attenuate pulmonary neutrophils infiltration induced by LPS. MFD could also decreased proinflammatory cytokines release and reduce reactive oxygen species (ROS) generation stimulated by LPS. Further, MFD could significantly reduce LPS-induced phosphorylation levels of mitogen-activated protein kinase (MAPK), increase expression of nuclear factor-erythroid 2 related factor 2 (Nrf2) and restore the expressions of antioxidant enzymes.

CONCLUSION

Our results firstly supported that MFD effectively protected LPS-induced ALI against inflammation and oxidative stress through inhibiting MAPK signaling pathway and activating Nrf2 pathway.

Fluorofenidone ameliorates cholestasis and fibrosis by inhibiting hepatic Erk/-Egr-1 signaling and Tgfβ1/Smad pathway in mice

Cholestasis is characterized by intrahepatic accumulation of bile acids (BAs), resulting in liver injury, fibrosis, and liver failure. To date, only ursodeoxycholic acid and obeticholic acid have been approved for the treatment of cholestasis. As fluorofenidone (AKF-PD) was previously reported to play significant anti-fibrotic and anti-inflammatory roles in various diseases, we investigated whether AKF-PD ameliorates cholestasis. A mouse model of cholestasis was constructed by administering a 0.1 % 3,5-diethoxycarbonyl-1,4-dihydroxychollidine (DDC) diet for 14 days. Male C57BL/6 J mice were treated with either AKF-PD or pirfenidone (PD) orally in addition to the DDC diet. Serum and liver tissues were subsequently collected and analyzed. We found that AKF-PD significantly reduced the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and total bile salts (TBA), as well as hepatic bile acids (BAs) levels. Hepatic histological analyses demonstrated that AKF-PD markedly attenuated hepatic inflammation and fibrosis. Further mechanistic analyses revealed that AKF-PD markedly inhibited expression of Cyp7a1, an enzyme key to BAs synthesis, by increasing Fxr nuclear translocation, and decreased hepatic inflammation by attenuating Erk/-Egr-1-mediated expression of inflammatory cytokines and chemokines Tnfα, Il-1β, Il-6, Ccl2, Ccl5 and Cxcl10. Moreover, AKF-PD was found to substantially reduce liver fibrosis via inhibition of Tgfβ1/Smad pathway in our mouse model. Here, we found that AKF-PD effectively attenuates cholestasis and hepatic fibrosis in the mouse model of DDC-induced cholestasis. As such, AKF-PD warrants further investigation as a candidate drug for treatment of cholestasis.

FLUOROFENIDONE ATTENUATES PULMONARY INFLAMMATION AND FIBROSIS BY INHIBITING THE IL-11/MEK/ERK SIGNALING PATHWAY

ABSTRACT

Idiopathic pulmonary fibrosis is defined as a specific form of chronic, progressive fibrosing interstitial pneumonia of unknown cause. Interleukin (IL)-11 plays an important role in the pathogenesis of idiopathic pulmonary fibrosis. In this study, we explore whether a potential antifibrotic agent fluorofenidone (FD) exerts its anti-inflammatory and antifibrotic effects through suppressing activation of the IL-11/MEK/ERK signaling pathway in vivo and in vitro. Male C57BL/6 J mice were intratracheally injected with bleomycin or saline. Fluorofenidone was administered throughout the course of the experiment. Lung tissue sections were stained with hemotoxylin and eosin, and Masson trichrome. Cytokines were measured using the enzyme-linked immunosorbent assay. The α-smooth muscle actin (α-SMA), fibronectin, and collagen I were measured using immunohistochemistry, and the phosphorylated extracellular signal-regulated kinase, phosphorylated mitogen-activated protein kinase, IL-11RA, and gp130 were measured using Western blot. The RAW264.7 cells and the normal human lung fibroblasts were treated with IL-11 and/or FD, IL-11RA-siRNA, or MEK inhibitor. The expressions of phosphorylated extracellular signal-regulated kinase, phosphorylated mitogen-activated protein kinase, IL-11RA, gp130, α-SMA, fibronectin, and collagen I were measured using Western blot and/or real-time polymerase chain reaction, and the cytokines were measured using enzyme-linked immunosorbent assay. Results showed that FD markedly reduced the expressions of IL-8, IL-18, IL-11, monocyte chemotactic protein-1, α-SMA, fibronectin, and collagen I in mice lung tissues. In addition, FD attenuated IL-11-induced expressions of α-SMA, fibronectin, and collagen I and inhibited IL-11RA, gp130, and phosphorylation of the ERK and MEK protein expression, as well as reduced the expressions of IL-8, IL-18, and monocyte chemotactic protein-1 in vitro. This study demonstrated that FD attenuated bleomycin-induced pulmonary inflammation and fibrosis in mice by inhibiting the IL-11/MEK/ERK signaling pathway.