Analyzing the molecular mechanism of xuefuzhuyu decoction in the treatment of pulmonary hypertension with network pharmacology and bioinformatics and verifying molecular docking.

BACKGROUND: XueFuZhuYu (XFZY), a typical Chinese herbal formula, has remarkable clinical effects for treating Pulmonary Hypertension (PH) with unclear mechanisms. Our research involved the utilization of network pharmacology to explore the traditional Chinese herbal monomers and their related targets within XFZY for PH treatment. Furthermore, molecular docking verification was performed. METHODS: The XFZY's primary active compounds, along with their corresponding targets, were both obtained from the TCMSP, ChEMBL, and UniProt databases. The target proteins relevant to PH were sifted through OMIM, GeneCards and TTD databases. The common "XFZY-PH" targets were evaluated with Disease Ontology (DO), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses with the assistance of R software. The Protein-Protein Interaction (PPI) network and compound-target-pathway network were constructed and a systematic analysis of network parameters was performed by the powerful software Cytoscape. Molecular docking was employed for assessing and verifying the interactions between the core targets and the top Chinese herbal monomer. RESULTS: The screening included 297 targets of active compounds in XFZY and 8400 PH-related targets. DO analysis of the above common 268 targets indicated that the treatment of the diseases by XFZY is mediated by genes related to Chronic Obstructive Pulmonary Disease (COPD), Obstructive Lung Disease (OLD), ischemia, and myocardial infarction. The findings from molecular docking indicated that the binding energies of 57 ligand-receptor pairs in PH and 20 ligand-receptor pairs in COPD-PH were lower than -7kJ•mol-1. CONCLUSIONS: This study indicates that XFZY is a promising option within traditional Chinese medicine compound preparation for combating PH, particularly in cases associated with COPD. Our demonstration of the specific molecular mechanism of XFZY anti-PH and its effective active ingredients provides a theoretical basis for better clinical application of the compound.

Synergizing the enhanced RIME with fuzzy K-nearest neighbor for diagnose of pulmonary hypertension.

Pulmonary hypertension (PH) is an uncommon yet severe condition characterized by sustained elevation of blood pressure in the pulmonary arteries. The delaying treatment can result in disease progression, right ventricular failure, increased risk of complications, and even death. Early recognition and timely treatment are crucial in halting PH progression, improving cardiac function, and reducing complications. Within this study, we present a highly promising hybrid model, known as bERIME_FKNN, which constitutes a feature selection approach integrating the enhanced rime algorithm (ERIME) and fuzzy K-nearest neighbor (FKNN) technique. The ERIME introduces the triangular game search strategy, which augments the algorithm's capacity for global exploration by judiciously electing distinct search agents across the exploratory domain. This approach fosters both competitive rivalry and collaborative synergy among these agents. Moreover, an random follower search strategy is incorporated to bestow a novel trajectory upon the principal search agent, thereby enriching the spectrum of search directions. Initially, ERIME is meticulously compared to 11 state-of-the-art algorithms using the IEEE CEC2017 benchmark functions across diverse dimensionalities such as 10, 30, 50, and 100, ultimately validating its exceptional optimization capability within the model. Subsequently, employing the color moment and grayscale co-occurrence matrix methodologies, a total of 118 features are extracted from 63 PH patients' and 60 healthy individuals' images, alongside an analysis of 14,514 recordings obtained from these patients utilizing the developed bERIME_FKNN model. The outcomes manifest that the bERIME_FKNN model exhibits a conspicuous prowess in the realm of PH classification, attaining an accuracy and specificity exceeding 99%. This implies that the model serves as a valuable computer-aided tool, delivering an advanced warning system for diagnosis and prognosis evaluation of PH.

Inhibition of pulmonary artery smooth muscle cells via the delivery of curcuminoid WZ35 by Cu-based metal organic frameworks.

Hypoxic pulmonary hypertension (HPH) is a life-threatening disease that occurs due to a lack of oxygen in the lungs, leading to an increase in pulmonary vascular resistance, right ventricular failure, and ultimately death. HPH is a multifactorial disorder that involves multiple molecular pathways, making it a challenge for clinicians to identify effective therapies. Pulmonary artery smooth muscle cells (PASMCs) play a crucial role in HPH pathogenesis by proliferating, resisting apoptosis, and promoting vascular remodelling. Curcumin, a natural polyphenolic compound, has shown potential as a therapeutic agent for HPH by reducing pulmonary vascular resistance, inhibiting vascular remodelling, and promoting apoptosis of PASMCs. Regulation of PASMCs could significantly inhibits HPH. However, curcumin has the disadvantages of poor solubility and low bioavailability, and its derivative WZ35 has better biosafety. Here, Cu-based metal organic frameworks (MOFCu ) was fabricated to encapsulate the curcumin analogue WZ35 (MOFCu @WZ35) for the inhibition of PASMCs proliferation. The authors found that the MOFCu @WZ35 could promote the death of PASMCs. Furthermore, the authors believed that this drug delivery system will effectively alleviate the HPH.

Directional mutation and crossover boosted ant colony optimization with application to COVID-19 X-ray image segmentation.

This paper focuses on the study of Coronavirus Disease 2019 (COVID-19) X-ray image segmentation technology. We present a new multilevel image segmentation method based on the swarm intelligence algorithm (SIA) to enhance the image segmentation of COVID-19 X-rays. This paper first introduces an improved ant colony optimization algorithm, and later details the directional crossover (DX) and directional mutation (DM) strategy, XMACO. The DX strategy improves the quality of the population search, which enhances the convergence speed of the algorithm. The DM strategy increases the diversity of the population to jump out of the local optima (LO). Furthermore, we design the image segmentation model (MIS-XMACO) by incorporating two-dimensional (2D) histograms, 2D Kapur's entropy, and a nonlocal mean strategy, and we apply this model to COVID-19 X-ray image segmentation. Benchmark function experiments based on the IEEE CEC2014 and IEEE CEC2017 function sets demonstrate that XMACO has a faster convergence speed and higher convergence accuracy than competing models, and it can avoid falling into LO. Other SIAs and image segmentation models were used to ensure the validity of the experiments. The proposed MIS-XMACO model shows more stable and superior segmentation results than other models at different threshold levels by analyzing the experimental results.

Multilevel threshold image segmentation for COVID-19 chest radiography: A framework using horizontal and vertical multiverse optimization.

COVID-19 is currently raging worldwide, with more patients being diagnosed every day. It usually is diagnosed by examining pathological photographs of the patient's lungs. There is a lot of detailed and essential information on chest radiographs, but manual processing is not as efficient or accurate. As a result, how efficiently analyzing and processing chest radiography of COVID-19 patients is an important research direction to promote COVID-19 diagnosis. To improve the processing efficiency of COVID-19 chest films, a multilevel thresholding image segmentation (MTIS) method based on an enhanced multiverse optimizer (CCMVO) is proposed. CCMVO is improved from the original Multi-Verse Optimizer by introducing horizontal and vertical search mechanisms. It has a more assertive global search ability and can jump out of the local optimum in optimization. The CCMVO-based MTIS method can obtain higher quality segmentation results than HHO, SCA, and other forms and is less prone to stagnation during the segmentation process. To verify the performance of the proposed CCMVO algorithm, CCMVO is first compared with DE, MVO, and other algorithms by 30 benchmark functions; then, the proposed CCMVO is applied to image segmentation of COVID-19 chest radiography; finally, this paper verifies that the combination of MTIS and CCMVO is very successful with good segmentation results by using the Feature Similarity Index (FSIM), the Peak Signal to Noise Ratio (PSNR), and the Structural Similarity Index (SSIM). Therefore, this research can provide an effective segmentation method for a medical organization to process COVID-19 chest radiography and then help doctors diagnose coronavirus pneumonia (COVID-19).

An Effective Machine Learning Approach for Identifying Non-Severe and Severe Coronavirus Disease 2019 Patients in a Rural Chinese Population: The Wenzhou Retrospective Study.

This paper has proposed an effective intelligent prediction model that can well discriminate and specify the severity of Coronavirus Disease 2019 (COVID-19) infection in clinical diagnosis and provide a criterion for clinicians to weigh scientific and rational medical decision-making. With indicators as the age and gender of the patients and 26 blood routine indexes, a severity prediction framework for COVID-19 is proposed based on machine learning techniques. The framework consists mainly of a random forest and a support vector machine (SVM) model optimized by a slime mould algorithm (SMA). When the random forest was used to identify the key factors, SMA was employed to train an optimal SVM model. Based on the COVID-19 data, comparative experiments were conducted between RF-SMA-SVM and several well-known machine learning algorithms performed. The results indicate that the proposed RF-SMA-SVM not only achieves better classification performance and higher stability on four metrics, but also screens out the main factors that distinguish severe COVID-19 patients from non-severe ones. Therefore, there is a conclusion that the RF-SMA-SVM model can provide an effective auxiliary diagnosis scheme for the clinical diagnosis of COVID-19 infection.

Gaussian Barebone Salp Swarm Algorithm with Stochastic Fractal Search for medical image segmentation: A COVID-19 case study.

An appropriate threshold is a key to using the multi-threshold segmentation method to solve image segmentation problems, and the swarm intelligence (SI) optimization algorithm is one of the popular methods to obtain the optimal threshold. Moreover, Salp Swarm Algorithm (SSA) is a recently released swarm intelligent optimization algorithm. Compared with other SI optimization algorithms, the optimization solution strategy of the SSA still needs to be improved to enhance further the solution accuracy and optimization efficiency of the algorithm. Accordingly, this paper designs an effective segmentation method based on a non-local mean 2D histogram and 2D Kapur's entropy called SSA with Gaussian Barebone and Stochastic Fractal Search (GBSFSSSA) by combining Gaussian Barebone and Stochastic Fractal Search mechanism. In GBSFSSSA, the Gaussian Barebone and Stochastic Fractal Search mechanism effectively balance the global search ability and local search ability of the basic SSA. The CEC2017 competition data set is used to prove the algorithm's performance, and GBSFSSSA shows an absolute advantage over some typical competitive algorithms. Furthermore, the algorithm is applied in image segmentation of COVID-19 CT images, and the results are analyzed based on three different metrics: peak signal-to-noise ratio (PSNR), structural similarity (SSIM), and feature similarity (FSIM), which can lead to the conclusion that the overall performance of GBSFSSSA is better than the comparison algorithm and can effectively improve the segmentation of medical images. Therefore, it is justified that GBSFSSSA is a reliable and effective method in solving the multi-threshold image segmentation problem.

Erratum: Astaxanthin prevents against lipopolysaccharide-induced acute lung injury and sepsis via inhibiting activation of MAPK/NF-κB.

[This corrects the article on p. 1884 in vol. 11, PMID: 30972212.].

Integrated bioinformatic analysis reveals the underlying molecular mechanism of and potential drugs for pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a devastating cardiovascular disease without a clear mechanism or drugs for treatment. Therefore, it is crucial to reveal the underlying molecular mechanism and identify potential drugs for PAH. In this study, we first integrated three human lung tissue datasets (GSE113439, GSE53408, GSE117261) from GEO. A total of 151 differentially expressed genes (DEGs) were screened, followed by KEGG and GO enrichment analyses and PPI network construction. Five hub genes (CSF3R, NT5E, ANGPT2, FGF7, and CXCL9) were identified by Cytoscape (Cytohubba). GSEA and GSVA were performed for each hub gene to uncover the potential mechanism. Moreover, to repurpose known and therapeutic drugs, the CMap database was retrieved, and nine candidate compounds (lypressin, ruxolitinib, triclabendazole, L-BSO, tiaprofenic acid, AT-9283, QL-X-138, huperzine-a, and L-741742) with a high level of confidence were obtained. Then ruxolitinib was selected to perform molecular docking simulations with ANGPT2, FGF7, NT5E, CSF3R, JAK1, JAK2, JAK3, TYK2. A certain concentration of ruxolitinib could inhibit the proliferation and migration of rat pulmonary artery smooth muscle cells (rPASMCs) in vitro. Together, these analyses principally identified CSF3R, NT5E, ANGPT2, FGF7 and CXCL9 as candidate biomarkers of PAH, and ruxolitinib might exert promising therapeutic action for PAH.

A history of cigarette smoking is associated with faster functional decline and reduction of entorhinal cortex volume in mild cognitive impairment.

Little is known about the longitudinal association of cigarette smoking with Alzheimer's Disease (AD) related markers in subjects with mild cognitive impairment (MCI). In this study, we aimed to examine the effect of a history of cigarette smoking on change in global cognition, verbal memory, functional performance, hippocampal volume, entorhinal cortex volume, brain glucose metabolism, and CSF AD pathologies over time in MCI subjects. At baseline, there were 870 subjects with MCI, including 618 non-smokers (no history of smoking) and 252 smokers (any lifetime history of smoking). Linear mixed models were fitted for each outcome with adjustment of several covariates. The major findings were: (1) Among older people with MCI, smokers showed faster decline in functional performance compared to non-smokers; (2) Smokers demonstrated steeper decline in entorhinal cortex volume than non-smokers; (3) A history of cigarette smoking was not associated with change in CSF Aß42, t-tau or p-tau levels over time in MCI subjects. In conclusion, we found that a history of cigarette smoking was associated with faster decline in functional performance and entorhinal cortex volume over time at the prodromal stage of dementia.

Elucidation of the Mechanisms and Molecular Targets of Qishen Yiqi Formula for the Treatment of Pulmonary Arterial Hypertension using a Bioinformatics/Network Topology-based Strategy.

BACKGROUND AND OBJECTIVE: Qishen Yiqi formula (QSYQ) is used to treat cardiovascular disease in the clinical practice of traditional Chinese medicine. However, few studies have explored whether QSYQ affects pulmonary arterial hypertension (PAH), and the mechanisms of action and molecular targets of QSYQ for the treatment of PAH are unclear. A bioinformatics/network topology-based strategy was used to identify the bioactive ingredients, putative targets, and molecular mechanisms of QSYQ in PAH. METHODS: A network pharmacology-based strategy was employed by integrating active component gathering, target prediction, PAH gene collection, network topology, and gene enrichment analysis to systematically explore the multicomponent synergistic mechanisms. RESULTS: In total, 107 bioactive ingredients of QSYQ and 228 ingredient targets were identified. Moreover, 234 PAH-related differentially expressed genes with a |fold change| >2 and an adjusted P value < 0.005 were identified between the PAH patient and control groups, and 266 therapeutic targets were identified. The pathway enrichment analysis indicated that 85 pathways, including the PI3K-Akt, MAPK, and HIF-1 signaling pathways, were significantly enriched. TP53 was the core target gene, and 7 other top genes (MAPK1, RELA, NFKB1, CDKN1A, AKT1, MYC, and MDM2) were the key genes in the gene-pathway network based on the effects of QSYQ on PAH. CONCLUSION: An integrative investigation based on network pharmacology may elucidate the multicomponent synergistic mechanisms of QSYQ in PAH and lay a foundation for further animal experiments, human clinical trials and rational clinical applications of QSYQ.

Asiaticoside attenuates bleomycin-induced pulmonary fibrosis in A2aR-/- mice by promoting the BMP7/Smad1/5 signaling pathway.

Idiopathic Pulmonary fibrosis(PF)is a chronic progressive disease, which is a lack of effective treatment,and the pathogenesis of IPF is not fully elucidated. Asiaticoside(AS) is isolated from Centella asiatica and has the effect of promoting scar healing and reducing scar formation. However,its possible role in idiopathic pulmonary fibrosis remains unclear. Adenosine A2A receptor (A2AR) is reported a protective factor in pulmonary fibrosis, and the bone morphogenetic protein 7 (BMP7) signaling pathway plays a crucial role in fibrosis in multiple organs. But the impact of A2AR on the BMP7 pathway has not yet been reported. Therefore, we hypothesized AS may promote the expression of A2AR, and then influence the BMP7/Smad1/5 pathway to alleviate pulmonary fibrosis. A2AR-/- mice and wild-type (WT) mice were administered bleomycin (BLM) by intratracheal injection. AS (50 mg/kg/d) was given daily for 28 days. AS reduced collagen deposition in lung tissue, interstitial lung inflammation. Furthermore, AS promoted A2AR expression and BMP7 pathway. Collectively, AS may attenuate BLM-induced pulmonary fibrosis by upregulating the BMP7 signaling pathway through A2AR.

Associations of cigarette smoking with memory decline and neurodegeneration among cognitively normal older individuals.

Cigarette smoking is associated with a higher risk of Alzheimer's disease (AD), but the underlying mechanisms remain to be clarified. In this study, we aimed to examine the effects of cigarette smoking on multiple AD biomarkers among older individuals with normal cognition (NC). Among 415 older individuals with NC from the Alzheimer's disease Neuroimaging Initiative (ADNI) cohort, we examined the associations between smoking status (non-smokers vs smokers) and global cognition, verbal memory, hippocampal volumes, cerebral glucose metabolism and CSF AD pathologies. The primary findings of this study were: (1) In NC, smokers showed worse performance on verbal memory tests [Rey Auditory Verbal Learning Test (RAVLT) total learning score and delayed recall] than non-smokers; (2) Compared with non-smokers, smokers had significantly lower HpVR; (3) Smokers, relative to non-smokers, demonstrated lower levels of cerebral glucose metabolism as measured by FDG-PET; and (4) there were no significant differences in CSF AD pathologies (CSF Aß42, t-tau or p-tau) between non-smokers and smokers. Longitudinal studies are needed to investigate the relationship between cigarettes smoking and changes in AD-related markers over time. Further, ADNI participants were highly educated and predominantly white. This may limit the generalizability of our results. In summary, among individuals with NC, cigarette smoking was associated with memory impairment, hippocampal atrophy and cerebral glucose hypometabolism, but not CSF AD pathologies.

L6H9 attenuates LPS-induced acute lung injury in rats through targeting MD2.

Acute lung injury (ALI) is a clinical syndrome characterized by respiratory failure and acute inflammatory response. Myeloid differentiation protein 2 (MD2) has been reported to play a pivotal role in the recognition of LPS and LPS-mediates inflammatory response. There have been no clinically effective therapeutic drugs for ALI. L6H9, an inhibitor of MD2, showed anti-inflammatory effects and cardiac protective activity. However, its effect on ALI has not been elucidated. In this study, intratracheal instillation of LPS was employed to induce ALI in rats. L6H9 pretreatment attenuates LPS-induced pathological variations in lung tissue and pulmonary edema. LPS instillation enhanced lung microvascular permeability, thereby causing inflammatory cells flow into bronchoalveolar lavage fluid (BALF). However, L6H9 inhibited the LPS-induced upregulation of total protein concentration and the number of inflammatory cells in BALF. In the meantime, macrophages infiltration in lung tissue induced by LPS was also mitigated by L6H9 treatment. Furthermore, L6H9 suppressed LPS-induced inflammatory cytokines expression in BALF, serum, and lung tissue. It is noteworthy that LPS-induced MD2/TLR4 complex formation was inhibited by L6H9 in lung tissue. On the whole, these results show that L6H9 can attenuate LPS-induced ALI in vivo by targeting MD2. Our study provide new candidate for the treatment of ALI.

Astaxanthin prevents against lipopolysaccharide-induced acute lung injury and sepsis via inhibiting activation of MAPK/NF-κB.

BACKGROUND: Endotoxin-induced acute inflammatory diseases such as sepsis, mediated by excessive production of various pro-inflammatory cytokines remain the leading cause of mortality in critically ill patients. Lipopolysaccharide (LPS), the characteristic endotoxin found in the outer membrane of Gram-negative bacteria, can induce the innate immunity system and through Mitogen activated protein kinase (MAPK) and Nuclear Factor-κB (NF-κB), increase the production of inflammatory mediators. Astaxanthin (ASX), a xanthophyll carotenoid, exerts beneficial effects against oxidation, inflammation, and cancer. But poor evidence has been reported that whether it has protective effects on LPS-induced injury. This study aims to investigate the effects of ASX on LPS-induced sepsis and acute lung injury and to demonstrate its mechanisms. METHODS: Mouse prime macrophage (MPM) challenged with LPS were used for in vitro pharmacological activity and mechanistic studies. Inflammatory facors (tumor necrosis factor-alpha and interleukin-6 levels) in MPM were determined. The mouse models of LPS-induced sepsis and acute lung injury administrated with or without the compound were used for in vivo studies. RESULTS: Pre-treatment of MPM with ASX inhibited MAPK/NF-κB signaling pathway, and attenuated LPS-increased inflammatory factors in vitro. In animal models of LPS-induced sepsis and acute lung injury, administration of ASX significantly improved survival and protected lung injury. Subsequently, ASX was shown to suppress LPS-induced inflammatory factors increase, MAPK phosphorylation, and NF-κB activation in vivo. CONCLUSIONS: ASX exerts impressively protective effects on LPS-induced injury in vitro and in vivo. Taken together, it might be used as a potential candidate for clinical sepsis.

T. marneffei infection complications in an HIV-negative patient with pre-existing pulmonary sarcoidosis: a rare case report.

BACKGROUND: Talaromyces marneffei (T. marneffei) is a thermal dimorphic pathogenic fungus that often causes fatal opportunistic infections in human immunodeficiency virus (HIV)-infected patients. Although T. marneffei-infected cases have been increasingly reported among non-HIV-infected patients in recent years, no cases of T. marneffei infection have been reported in pulmonary sarcoidosis patients. In this case, we describe a T. marneffei infection in an HIV-negative patient diagnosed with pulmonary sarcoidosis. CASE PRESENTATION: A 41-year-old Chinese man who had pre-existing pulmonary sarcoidosis presented with daily hyperpyrexia and cough. Following a fungal culture from bronchoalveolar lavage (BAL), the patient was diagnosed with T. marneffei infection. A high-resolution computed tomography (HRCT) chest scan revealed bilateral lung diffuse miliary nodules, multiple patchy exudative shadows in the bilateral superior lobes and right inferior lobes, air bronchogram in the consolidation of the right superior lobe, multiple hilar and mediastinal lymphadenopathies and local pleural thickening. After 3 mos of antifungal therapy, the patient's pulmonary symptoms rapidly disappeared, and the physical condition improved markedly. A subsequent CT re-examination demonstrated that foci were absorbed remarkably after treatment. The patient is receiving follow-up therapy and assessment for a cure. CONCLUSION: This case suggested that clinicians should pay more attention to non-HIV-related lung infections in patients with pulmonary sarcoidosis. Early diagnosis and treatment with antifungal therapy can improve the prognosis of T. marneffei infection.

FGF21 attenuates hypoxia­induced dysfunction and apoptosis in HPAECs through alleviating endoplasmic reticulum stress.

Vascular endothelial apoptosis and dysfunction have a crucial role in triggering pathological vascular remodeling of hypoxia­induced pulmonary arterial hypertension (PAH). Fibroblast growth factor (FGF)21, an endocrine regulator, has recently been reported to protect cardiac endothelial cells from damage and suppress inflammatory responses. In addition, FGF21 is reported to be involved in endoplasmic reticulum stress (ERS). Previous studies have suggested that ERS participates in the development of PAH, and attenuation of ERS could be an effective therapeutic strategy for the protection of pulmonary arteries. However, whether FGF21 has a protective function via suppression of ERS in pulmonary arterial endothelial cells in hypoxia remains unclear. The present study aimed to explore whether FGF21 could reduce the hypoxia­induced apoptosis of human pulmonary arterial endothelial cells (HPAECs) and prevent endothelial dysfunction via the inhibition of ERS. HPAECs were divided into six groups: Normoxia, hypoxia, hypoxia plus FGF21, hypoxia plus salubrinal (an ERS inhibitor), hypoxia plus tunicamycin (an ERS agonist), and hypoxia plus tunicamycin plus FGF21. The endoplasmic reticulum ultrastructure in HPAECs was assessed by transmission electron microscopy, and proliferation and apoptosis were examined by cell counting kit­8 and terminal deoxyribonucleotide transferase­mediated dUTP nick end­labelling assays, respectively. The expression levels of ERS­related proteins, including binding immunoglobulin protein (BiP), protein kinase R­like endoplasmic reticulum kinase (PERK), phosphorylated (p­) PERK, transcription factor C/EBP homologous protein (CHOP), B­cell lymphoma-2 (Bcl­2) and caspase­4 were detected by western blotting. Transwell migration chamber assays were performed, and the concentration of nitric oxide (NO)/endothelin­1 (ET­1) in the culture medium was determined to examine endothelial function. The results revealed that hypoxia increased the % of apoptotic cells and diminished the viability of HPAECs, accompanied by an upregulation of ERS­dependent apoptosis by increasing the expression of the proapoptotic caspase­4 and decreasing the antiapoptotic Bcl­2. Additionally, hypoxia upregulated the expression of representative proteins in the PERK branch of ERS, including BiP, p­PERK and CHOP, while it downregulated the expression of PERK. Furthermore, the secretion of NO/ET­1 and the migration rate of HPAECs were downregulated under conditions of hypoxia. FGF21 significantly attenuated the hypoxia­induced apoptosis and dysfunction of HPAECs through alleviating the aforementioned changes in ERS­dependent signaling pathways. In conclusion, ERS may be a crucial mechanism in the hypoxia­induced apoptosis and endothelial dysfunction of HPAECs. FGF21 may attenuate the hypoxia­induced apoptosis and dysfunction of HPAECs through alleviating ERS, via the PERK/CHOP signaling pathway and inhibition of caspase­4 expression.

Effect of asiaticoside on endothelial cells in hypoxia­induced pulmonary hypertension.

Pulmonary hypertension (PH) is a chronic progre-ssive disease with limited treatment options. The exact etiology and pathogenesis of PH remain to be elucidated, however there is novel evidence that implicates abnormal endothelial cells (ECs) apoptosis and dysfunction of ECs to be involved in the initiation of PH. Asiaticoside (AS) is a saponin monomer extracted from a medicinal plant called Centella asiatica, which had a preventing effect of hypoxia­induced pulmonary hypertension (hypoxic PH) by blocking transforming growth factor­ß1/SMAD family member 2/3 signaling in our previous study. The present study demonstrated that AS can prevent the development of hypoxic PH and reverse the established hypoxic PH. AS may activate the nitric oxide (NO)­mediated signals by enhancing the phosphorylation of serine/threonine­specific protein kinase/eNOS, thus promoting NO production, and prevent ECs from hypoxia­induced apoptosis. All these findings imply that AS may be a potential therapeutic option for hypoxic PH patients due to its effect on the vitality and function of endothelial cells.

Salidroside attenuates hypoxia-induced pulmonary arterial smooth muscle cell proliferation and apoptosis resistance by upregulating autophagy through the AMPK-mTOR-ULK1 pathway.

BACKGROUND: Recent studies have shown that both adenosine monophosphate activated protein kinase (AMPK) and the mammalian target of rapamycin (mTOR) are energy sensors and are related to autophagy. Our recent reports have shown that salidroside can exert protective effects against hypoxia-induced pulmonary arterial smooth muscle cell (PASMC) proliferation and apoptosis resistance through the AMPK pathway. This study aims to explore the relationship among AMPK, mTOR and ULK1 in PASMCs under hypoxic conditions and to investigate whether the protective effects of salidroside are related to the autophagic cell death pathway. METHODS: Rat PASMCs were cultured and divided into five groups: the normoxia, hypoxia, hypoxia + MHY1485 (mTOR agonist), hypoxia + rapamycin (mTOR inhibitor) and hypoxia + salidroside groups. Hypoxic cells were treated as indicated for 24 h. Cell viability was evaluated by the CCK-8 assay. Cell apoptosis was measured by the TUNEL assay. The autophagy flux of PASMCs was evaluated with tandem mRFP-GFP fluorescence microscopy. Autophagosomes were detected by electron microscopy. Protein expression of LC3, p62, AMPK, P-AMPK (Thr 172), P-ULK1 (Ser 555 and Ser 317), mTOR, P-mTOR (Ser 2448), ULK1 and P-ULK1 (Ser 757) was detected by western blot assay. RESULTS: PASMC proliferation and apoptosis resistance were observed under hypoxic conditions. Autophagy flux, the number of autophagosomes and the LC3II/LC3I ratio were increased in the hypoxia group compared with the normoxia group, whereas p62 expression was decreased. Treatment with rapamycin or salidroside reversed hypoxia-induced PASMC proliferation and apoptosis resistance and further increased autophagy flux, autophagosome levels and the LC3II/LC3I ratio but decreased p62 expression. Treatment with MHY1485 reversed hypoxia-induced PASMC apoptosis resistance and decreased autophagy flux as well as increased autophagosome levels, the LC3II/LC3I ratio and p62 expression. P-AMPK (Thr 172) and P-ULK1 (Ser 555) of the AMPK-ULK1 pathway were increased in the hypoxia group and were further increased in the salidroside group. Rapamycin and MHY1485 had no effect on either P-AMPK (Thr 172) or P-ULK1 (Ser 555). Phosphorylation of ULK1 at serine 317 did not significantly affect the five groups. Furthermore, P-mTOR (Ser 2448) and P-ULK1 (Ser 757) of the AMPK-mTOR-ULK1 pathway were decreased in the hypoxia group and were further decreased in the salidroside group. MHY1485 increased the expression of both P-mTOR(Ser 2448) and P-ULK1(Ser 757), whereas rapamycin had the opposite effect. CONCLUSIONS: Salidroside might inhibit hypoxia-induced PASMC proliferation and reverse apoptosis resistance via the upregulation of autophagy through both the AMPKα1-ULK1 and AMPKα1-mTOR-ULK1 pathways.

Activation of A2aR attenuates bleomycin-induced pulmonary fibrosis via the SDF-1/CXCR4 axis-related pathway.

Previous studies in our lab have demonstrated that Adenosine A2a receptor (A2aR) gene-knockout mice were vulnerable to pulmonary fibrosis induced by bleomycin (BLM). Inhibition of the SDF-1/CXCR4 axis has been reported to protect the lungs from fibrogenesis in BLM-exposed mice. Little is yet known about the relationships between A2aR and the SDF-1/CXCR4 axis in idiopathic pulmonary fibrosis (IPF). This study probes the role of A2aR in the fibrotic process and explores the relationship between A2aR and the SDF-1/CXCR4 axis in BLM-induced pulmonary fibrosis in mice. In the study, A2aR-/- and A2aR+/+ BALB/c mice were exposed to BLM by intratracheal instillation, and CGS-21680 (CGS), an A2aR agonist, was administered daily for 28 days to the A2aR+/+ mice in the BLM-induced fibrosis group. Activation of A2aR produced an anti-fibrotic effect as indicated by the evaluations of the lung architecture, microstructure and ultrastructure. The quantitative analysis indicated that treatment with CGS significantly reduced the collagen content in lungs. To explore the potential mechanisms, the expression levels of A2aR, SDF-1, and CXCR4 were subsequently determined using ELISA, in situ hybridization (ISH), immunohistochemical staining and western blotting techniques. Administration of CGS markedly suppressed the elevated expression levels of SDF-1 and CXCR4. Moreover, the A2aR-/- mice developed more severe pulmonary fibrosis than the normal mice when exposed to BLM. Furthermore, the SDF-1/CXCR4 axis was aberrantly uninhibited in the knockout mice. Together, these findings indicated that A2aR alleviated BLM-induced lung fibrosis, at least partially via the SDF-1/CXCR4 pathway, which could be a potential therapeutic target for the treatment of IPF.