Aqueous extract of Platycodon grandiflorus attenuates lipopolysaccharide-induced apoptosis and inflammatory cell infiltration in mouse lungs by inhibiting PI3K/Akt signaling.

BACKGROUND: Acute lung injury (ALI), an acute inflammatory lung disease, can cause a rapid inflammatory response in clinic, which endangers the patient's life. The components of platycodon grandiflorum, such as platycodins have a wide range of pharmacological activities such as expectorant, anti-apoptotic, anti-inflammatory, anti-tumor and anti-oxidant properties, and can be used for improving human immunity. Previous studies have shown that aqueous extract of platycodon grandiflorum (PAE) has a certain protective effect on ALI, but the main pharmacodynamic components and the mechanism of action are not clear. METHODS: The anti-inflammatory properties of PAE were studied using the lipopolysaccharide (LPS)-induced ALI animal model. Hematoxylin and eosin stains were used to assess the degree of acute lung damage. Changes in RNA levels of pro-inflammatory cytokines in the lungs were measured using quantitative RT-qPCR. The potential molecular mechanism of PAE preventing ALI was predicted by lipidomics and network pharmacology. To examine the anti-apoptotic effects of PAE, TdT-mediated dUTP nick-end labelling (TUNEL) was employed to determine apoptosis-related variables. The amounts of critical pathway proteins and apoptosis-related proteins were measured using Western blotting. RESULTS: Twenty-six chemical components from the PAE were identified, and their related pathways were obtained by the network pharmacology. Combined with the analysis of network pharmacology and literature, it was found that the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) signaling pathway is related to ALI. The results of lipidomics show that PAE alleviates ALI via regulating lung lipids especially phosphatidylinositol (PI). Finally, the methods of molecular biology were used to verify the mechanism of PAE. It can be found that PAE attenuates the inflammatory response to ALI by inhibiting apoptosis through PI3K/Akt signaling pathway. CONCLUSION: The study revealed that the PAE attenuates lipopolysaccharide-induced apoptosis and inflammatory cell infiltration in mouse lungs by inhibiting PI3K/Akt signaling. Furthermore, our findings provide a novel strategy for the application of PAE as a potential agent for preventing patients with ALI.

Biomechanical Responses of Different Cap Thicknesses of Corneas After Small Incision Lenticule Extraction: Finite Element Analysis.

Purpose: This study analyzed the biomechanical responses of different corneal cap thicknesses after small incision lenticule extraction (SMILE). Methods: Individual finite element models of myopic eyes were constructed based on the clinical data. Then, four types of corneal cap thicknesses after SMILE were included for each model. The biomechanical effects of material parameters and intraocular pressure on corneas with different cap thicknesses were analyzed. Results: When the cap thickness increased, the vertex displacements of the anterior and posterior corneal surfaces decreased slightly. The corneal stress distributions demonstrated little change. Regarding wave-front aberrations caused by the displacements of the anterior surface, the absolute defocus value decreased slightly, but the magnitude of primary spherical aberration increased slightly. The horizontal coma increased, and the levels of other low-order and high-order aberrations were small and demonstrated little change. The corneal vertex displacement and wave-front aberration were significantly affected by elastic modulus and intraocular pressure, whereas the corneal stress distribution was greatly affected by intraocular pressure. There were obvious individual differences in the biomechanical responses of human eyes. Conclusions: The biomechanical difference of different corneal cap thicknesses after SMILE was small. The effect of corneal cap thickness was significantly less than that resulting from material parameters and intraocular pressure. Translational Relevance: Individual models were constructed based on the clinical data. The elastic modulus was controlled by programming to simulate its heterogeneous distribution in the actual human eye. The simulation was improved to bridge the gap between basic research and clinical care.

Platycodon grandiflorus root extract activates hepatic PI3K/PIP3/Akt insulin signaling by enriching gut Akkermansia muciniphila in high fat diet fed mice.

BACKGROUND: Increasing hepatic insulin signaling is found to be an important mechanism of Platycodon grandiflorus root to alleviate metabolic syndrome (MetS) symptoms such as insulin resistance, obesity, hyperlipidemia and hepatic steatosis, but the details are not yet clear. Since the main constituents of Platycodon grandiflorus root were hard to be absorbed by gastrointestinal tract, getting opportunity to interact with gut microbiota, we speculate the gut microorganisms may mediate its effect. PURPOSE: Our work aimed to confirm the critical role of gut microbes in the intervention of Platycodon grandiflorus root extract (PRE) on MetS, and investigate the mechanism. METHODS: Biochemical analyses, glucose tolerance test and hepatic lipidomics analysis were used to evaluate the anti-MetS effect of PRE on high fat diet (HFD) fed mice. Perform 16S rDNA analysis, qPCR analysis and in vitro co-incubation experiment to study its effect on gut microbes, followed by fecal microbiota transplantation (FMT) experiment and antibiotics intervention experiment. Also, the effect of Akkermansia muciniphila treatment on HFD mice was investigated. RESULTS: PRE alleviated lipid accumulation and insulin resistance in HFD mice and remodeled the fecal microbiome. It also increased the gene expression of colonic tight junction proteins, alleviated metabolic endotoxemia and inflammation, so that reduced TNF-α induced hepatic JNK-dependent IRS-1 serine phosphorylation and the impairment of PI3K/PIP3/Akt insulin signaling pathway. A. muciniphila was one of the most significantly enriched microbes by PRE treatment, and its administration to HFD mice showed similar effects to PRE, repairing the gut barrier and activating hepatic PI3K/PIP3/Akt pathway. Finally, anti-MetS effect of PRE could be delivered to FMT recipients, and PRE could not further attenuate MetS in gut microbiota depleted mice. CONCLUSION: We demonstrated for the first time that PRE alleviated MetS in a gut microbiota dependent manner, and found activation of hepatic insulin signaling mediated by gut A. muciniphila was a potential mechanism of it.

Acteoside attenuates RSV-induced lung injury by suppressing necroptosis and regulating metabolism.

Background: Necroptosis and inflammation are closely related to the pathogenesis of respiratory syncytial virus (RSV). Acteoside (AC), a natural phenylpropanoid glycoside from Kuding Tea, has significant anti-RSV effect. However, the roles of AC on RSV-induced lung necroptosis and inflammation are yet to be elucidated. Methods: The effects of AC were investigated in BALB/c mice and A549 cells. Lung histopathology was observed through H&E staining. The viral titer was assessed via plaque assay. The RSV-F expression was determined by RT-qPCR and immunohistochemistry assay. The levels of cytokines were detected by ELISA and RT-qPCR. The necroptosis rate and mitochondrial membrane potential were evaluated via flow cytometry. The expressions of HMGB1/NF-κB and RIP1/RIP3/MLKL/PGAM5/DRP1 were detected by western blot. Additionally, untargeted metabolomics was conducted to investigate the metabolic profiles and related metabolic pathways via Gas Chromatography-Mass Spectrometry. Results: The results showed that compared with the RSV-infected group, AC treatment significantly attenuated lung pathological damage, virus replication, and cytokines levels. AC also alleviated RSV-induced necroptosis and mitochondrial dysfunction in vitro and in vivo. Moreover, AC treatment down-regulated the expression of HMGB1, p-Iκbα/Iκbα, p-p65/p65, RIP1, RIP3, MLKL, PGAM5, and DRP1. Furthermore, metabolomic analyses suggested that the perturbations in major metabolites of AC therapy were related to variations in amino acid and energy metabolism. Conclusion: Our findings validated the beneficial effects of AC in suppressing necroptosis and regulating metabolism, suggesting AC may be a new drug candidate for RSV infection.

Revealing the mechanism of Jiegeng decoction attenuates bleomycin-induced pulmonary fibrosis via PI3K/Akt signaling pathway based on lipidomics and transcriptomics.

BACKGROUND: Pulmonary fibrosis (PF) is a serious lung disease with unknown etiology and irreversible course. Jiegeng decoction (JGD), a traditional prescription, is widely used to treat lung diseases due to its anti-inflammatory and expectorant effects. PURPOSE: To explore the effect of JGD on mice with PF and its underlying mechanism. For this purpose, we established a mouse model with PF by bleomycin (BLM) and then administered JGD and pirfenidone at different concentrations. RESULTS: In vivo, JGD was found to reduce lung inflammation, improve lung function and decrease collagen deposition to alleviate bleomycin-induced PF in mice. The mouse lung tissue was analyzed using lipidomics and transcriptomics. We found phosphatidylinositol was decreased after JGD treatment in lipidomics results, while transcriptomics results showed the critical roles of PI3K/Akt signaling pathway in JGD treatment group. Then, Western Blot and Immunohistochemistry were used to validate that JGD may regulate the expression of Bax, Caspase3, Caspase8, Caspase9 and Bcl-2 apoptosis-related proteins via PI3K/Akt signaling pathway. TUNEL staining revealed that apoptosis mainly occurs on AEC IIs. CONCLUSION: Our results showed that JGD inhibits apoptosis through the PI3K/Akt signaling pathway, thereby protecting against BLM-induced PF. Hence, JGD is expected to be a potential drug candidate for the treatment of PF.