Clinical and experimental phenotype of azole-resistant Aspergillus fumigatus with a HapE splice site mutation: a case report.

BACKGROUND: The recent increase in cases of azole-resistant Aspergillus fumigatus (ARAf) infections is a major clinical concern owing to its treatment limitations. Patient-derived ARAf occurs after prolonged azole treatment in patients with aspergillosis and involves various cyp51A point mutations or non-cyp51A mutations. The prognosis of patients with chronic pulmonary aspergillosis (CPA) with patient-derived ARAf infection remains unclear. In this study, we reported the case of a patient with ARAf due to HapE mutation, as well as the virulence of the isolate. CASE PRESENTATION: A 37-year-old male was presented with productive cough and low-grade fever. The patient was diagnosed with CPA based on the chronic course, presence of a fungus ball in the upper left lobe on chest computed tomography (CT), positivity for Aspergillus-precipitating antibody and denial of other diseases. The patient underwent left upper lobe and left S6 segment resection surgery because of repeated haemoptysis during voriconazole (VRC) treatment. The patient was postoperatively treated with VRC for 6 months. Since then, the patient was followed up without antifungal treatment but relapsed 4 years later, and VRC treatment was reinitiated. Although an azole-resistant isolate was isolated after VRC treatment, the patient did not show any disease progression in either respiratory symptoms or radiological findings. The ARAf isolated from this patient showed slow growth, decreased biomass and biofilm formation in vitro, and decreased virulence in the Galleria mellonella infection model compared with its parental strain. These phenotypes could be caused by the HapE splice site mutation. CONCLUSIONS: This is the first to report a case demonstrating the clinical manifestation of a CPA patient infected with ARAf with a HapE splice site mutation, which was consistent with the in vitro and in vivo attenuated virulence of the ARAf isolate. These results imply that not all the ARAf infections in immunocompetent patients require antifungal treatment. Further studies on the virulence of non-cyp51A mutations in ARAf are warranted.

Current pharmacological modalities for management of novel coronavirus disease 2019 (COVID-19) and the rationale for their utilization: A review.

SARS-CoV-2 has caused a pandemic which is putting strain on the health-care system and global economy. There is much pressure to develop both preventative and curative therapies for SARS-CoV-2 as there is no evidence to support therapies to improve outcomes in patients with SARS-CoV-2. Medications that inhibit certain steps of virus life cycle that are currently used to treat other illnesses such as Malaria, Ebola, HIV and Hepatitis C are being studied for use against SARS-CoV-2. To date, data is limited for medications that facilitate clinical improvement of COVID-19 infections.

Pneumolysis and "Silent Hypoxemia" in COVID-19.

COVID-19 can evolve to a severe lung compromise with life-threatening hypoxemia. The mechanisms involved are not fully understood. Their understanding is crucial to improve the outcomes. Initially, past-experience lead to the implementation of standardized protocols assuming this disease would be the same as SARS-CoV. Impulsive use of ventilators in extreme cases ended up in up to 88% fatality. We compare medical and physiological high altitude acute and chronic hypoxia experience with COVID-19 hypoxemia. A pathophysiological analysis is performed based on literature review and histopathological findings. Application of the Tolerance to Hypoxia formula = Hemoglobin/PaCO2 + 3.01 to COVID-19, enlightens its critical hypoxemia. Pneumolysis is defined as progressive alveolar-capillary destruction resulting from the CoV-2 attack to pneumocytes. The adequate interpretation of the histopathological lung biopsy photomicrographs reveals these alterations. The three theoretical pathophysiological stages of progressive hypoxemia (silent hypoxemia, gasping, and death zone) are described. At high altitude, normal low oxygen saturation (SpO2) levels (with intact lung tissue and adequate acid-base status) could be considered silent hypoxemia. At sea level, in COVID-19, the silent hypoxemia starting at SpO2 ≤ 90% (comparable to a normal SPO2 {88-92%} at 3500 m) suddenly evolves to critical hypoxemia. This, as a consequence of progressive pneumolysis + inflammation + overexpressed immunity + HAPE-type edema resulting in pulmonary shunting. The proposed treatment is based on the improvement of the Tolerance to Hypoxia (Hemoglobin factor), oxygen therapy, inflammation reduction, antibiotics, antitussives, rehydration & anticoagulation if required. Understanding the pathophysiology of COVID-19 may assist in this disease's management.

Nitric oxide restores peripheral blood mononuclear cell adhesion against hypoxia via NO-cGMP signalling.

Hypoxia is the most detrimental threat to humans residing at high altitudes, affecting multifaceted cellular responses that are crucial for normal homeostasis. Inhalation of nitric oxide has been successfully implemented to combat the hypoxia effect in the high altitude patients. We hypothesize that nitric oxide (NO) restores the peripheral blood mononuclear cell-matrix deadhesion during hypoxia. In the present study, we investigate the cellular action of exogenous NO in the hypoxia-mediated diminution of cell-matrix adhesion of PBMNC and NO bioavailability in vitro. The result showed that NO level and cell-matrix adhesion of PBMNC were significantly reduced in hypoxia as compared with normoxia, as assessed by the DAF-FM and cell adhesion assay, respectively. In contrast, cellular oxidative damage response was indeed upregulated in hypoxic PBMNC. Further, gene expression analysis revealed that mRNA transcripts of cell adhesion molecules (Integrin α5 and ß1) and eNOS expressions were significantly downregulated. The mechanistic study revealed that administration of NO and 8-Br-cGMP and overexpression of eNOS-GFP restored the basal NO level and recovers cell-matrix adhesion in PBMNC via cGMP-dependent protein kinase I (PKG I) signalling. In conclusion, NO-cGMP/PKG signalling may constitute a novel target to recover high altitude-afflicted cellular deadhesion. SIGNIFICANCE OF THIS STUDY: Cellular adhesion is a complex multistep process. The ability of cells to adhere to extracellular matrix is an essential physiological process for normal homeostasis and function. Hypoxia exposure in the PBMNC culture has been proposed to induce oxidative damage and cellular deadhesion and is generally believed to be the key factor in the reduction of NO bioavailability. In the present study, we demonstrated that NO donor or overexpression of eNOS-GFP has a protective effect against hypoxia-induced cellular deadhesion and greatly improves the redox balance by inhibiting the oxidative stress. Furthermore, this protective effect of NO is mediated by the NO-cGMP/PKG signal pathway, which may provide a potential strategy against hypoxia.

High Altitude Pulmonary Edema in Children: A Single Referral Center Evaluation.

OBJECTIVE: To describe the clinical features of children who presented to Children's Hospital Colorado (CHCO) with high-altitude pulmonary edema (HAPE). STUDY DESIGN: We performed a retrospective chart review in children discharged from CHCO (an elevation of 1668 m) with a clinical diagnosis of HAPE and a chest radiograph consistent with noncardiogenic pulmonary edema. Descriptive statistics were used to describe the demographics, presentations, and treatment strategies. RESULTS: From 2004 to 2014, 50 children presented to CHCO who were found to have a clinical diagnosis of HAPE and a chest radiograph consistent with noncardiogenic pulmonary edema. Most (72%) patients were male, and most (60%) of the children in the study were diagnosed with classic HAPE, 38% with re-entry HAPE, and 2% with high altitude resident pulmonary edema. Elevation at symptom presentation ranged from 1840 to 3536 m. Patients were treated with a variety of medications, including diuretics, steroids, and antibiotics. Four patients were newly diagnosed with structural heart findings: 2 patients with patent foramen ovale and 2 with atrial septal defects. Eleven patients had findings consistent with pulmonary hypertension at the time of echocardiography. CONCLUSIONS: HAPE symptoms may develop below 2500 m, so providers should not rule out HAPE based on elevation alone. Structural heart findings and pulmonary hypertension are associated with HAPE susceptibility and their presence may inform treatment. Inappropriate use of antibiotics and diuretics in children with HAPE suggest that further education of providers is warranted.

Successful Summit of Two 8000 m Peaks After Recent High Altitude Pulmonary Edema.

There is little information in the literature on the safety of reascent to high altitude shortly after resolution of severe acute altitude illness, including high altitude pulmonary or cerebral edema. We present a case of a 52-y-old male climber who was diagnosed with high altitude pulmonary edema during the 2018 Everest spring climbing season, descended to low altitude for 9 d, received treatment, and returned to continue climbing with a very rapid ascent rate. Despite a very recent history of high altitude pulmonary edema and not using pharmacologic prophylaxis over a very rapid reascent profile, the climber successfully summited Mt. Everest (8848 m) and Lhotse (8516 m) without any problems.

NR3C2 Gene is Associated with Susceptibility to High-Altitude Pulmonary Edema in Han Chinese.

INTRODUCTION: The mineralocorticoid receptor is encoded by the NR3C2 gene and plays an important role in regulating vascular tone in high-altitude pulmonary edema (HAPE). This study aimed to investigate the association of the polymorphisms in the NR3C2 gene with HAPE susceptibility in Han Chinese. METHODS: We enrolled 133 HAPE patients and 131 matched healthy Han Chinese from the Yushu area in Qinghai, where the altitude is greater than 3500 m. Two single nucleotide polymorphisms (SNPs) of the NR3C2 gene, rs2070951 and rs5522, were genotyped by the Sequenom MassARRAY SNP assay. RESULTS: The genotypic distributions and allele frequencies of NR3C2 SNP rs5522 were significantly different between the HAPE and control groups (P<0.05). The frequency of the A allele of rs5522 was significantly higher in the HAPE group than in the control group (P<0.05) with an odds ratio of 1.7 (95% CI: 1.0-2.8). There were no significant differences in the genotypic distributions and allele frequencies of NR3C2 SNP rs2070951 between the HAPE and control groups. The frequencies of the C-A and C-G haplotypes were significantly higher in the HAPE group than in control group. CONCLUSIONS: The rs5522 polymorphism of the NR3C2 gene was associated with HAPE susceptibility in Chinese subjects. The A allele may contribute to the susceptibility to HAPE. The frequency of the C-A and C-G haplotypes of rs2070951 and rs5522 in the NR3C2 gene may increase the risk of HAPE.

Culture-Based Methods and Molecular Tools for Azole-Resistant Aspergillus fumigatus Detection in a Belgian University Hospital.

Azole-resistant Aspergillus fumigatus is an increasing worldwide problem with major clinical implications. Surveillance is warranted to guide clinicians to provide optimal treatment to patients. To investigate azole resistance in clinical Aspergillus isolates in our institution, a Belgian university hospital, we conducted a laboratory-based surveillance between June 2015 and October 2016. Two different approaches were used: a prospective culture-based surveillance using VIPcheck on unselected A. fumigatus (n = 109 patients, including 19 patients with proven or probable invasive aspergillosis [IA]), followed by molecular detection of mutations conferring azole resistance, and a retrospective detection of azole-resistant A. fumigatus in bronchoalveolar lavage fluid using the commercially available AsperGenius PCR (n = 100 patients, including 29 patients with proven or probable IA). By VIPcheck, 25 azole-resistant A. fumigatus specimens were isolated from 14 patients (12.8%). Of these 14 patients, only 2 had proven or probable IA (10.5%). Mutations at the cyp51A gene were observed in 23 of the 25 A. fumigatus isolates; TR34/L98H was the most prevalent mutation (46.7%), followed by TR46/Y121F/T289A (26.7%). Twenty-seven (27%) patients were positive for the presence of Aspergillus species by AsperGenius PCR. A. fumigatus was detected by AsperGenius in 20 patients, and 3 of these patients carried cyp51A mutations. Two patients had proven or probable IA and cyp51A mutation (11.7%). Our study has shown that the detection of azole-resistant A. fumigatus in clinical isolates was a frequent finding in our institution. Hence, a rapid method for resistance detection may be useful to improve patient management. Centers that care for immunocompromised patients should perform routine surveillance to determine their local epidemiology.

Telomere length-related gene ACYP2 polymorphism is associated with the risk of HAPE in Chinese Han population.

BACKGROUND: High altitude pulmonary edema (HAPE) is a type of pneumonedema that mostly occurs under conditions such as high altitude, rapid ascent and hypoxia, amongst others. The ACYP2 polymorphism is suggested to be associated with mean telomere length, and telomere length is significantly longer at a moderate attitude than at sea-level or at simulated high attitude. The present study aimed to determine whethher there is any association between ACYP2 polymorphism and the risk of HAPE. METHODS: A total of 265 patients and 303 healthy controls were enrolled in our case-control study. Six SNPs were selected and genotyped using the Sequenom MassARRAY method. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated by unconditional logistic regression with adjustment for gender and age. RESULTS: Using chi-squared tests, we found that the minor allele G of rs11896604 is significantly associated with a decreased risk of HAPE [odds ratio (OR) = 0.87, 95% confidence interval (CI) = 0.65-1.16, p = 0.048]. We also found that the 'A/A' genotype of rs12615793 is associated with a decreased risk of HAPE based on the recessive model (OR =0.28; 95% CI = 0.09-0.88; p = 0.017). Additionally, the 'G/G' genotype of rs11896604 was found to be associated with a decreased risk of HAPE based on the codominant model (OR =0.26; 95% CI = 0.08-0.79; p = 0.025) and recessive model (OR =0.25; 95% CI = 0.08-0.77; p = 0.007). However, only rs11896604 remained significant after Bonferroni correction (p < 0.0083). CONCLUSIONS: The present study found that the ACYP2 gene polymorphism significantly decreased the risk of HAPE. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Hypoxia-Induced Inflammatory Chemokines in Subjects with a History of High-Altitude Pulmonary Edema.

High altitude hypoxia is known to induce an inflammatory response in immune cells. Hypoxia induced inflammatory chemokines may contribute to the development of high altitude pulmonary edema (HAPE) by causing damage to the lung endothelial cells and thereby capillary leakage. In the present study, we were interested to know whether chronic inflammation may contribute to HAPE susceptibility. We examined the serum levels of macrophage inflammatory protein-1α (MIP-1α), monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 in group (1) HAPE Susceptible subjects (n = 20) who had past history of HAPE and group (2) Control (n = 18) consist of subjects who had stayed at high altitude for 2 years without any history of HAPE. The data obtained confirmed that circulating MCP-1, MIP-1α were significantly upregulated in HAPE-S individuals as compared to the controls suggestive of chronic inflammation. However, it is not certain whether chronic inflammation is cause or consequence of previous episode of HAPE. The moderate systemic increase of these inflammatory markers may reflect considerable local inflammation. The existence of enhanced level of inflammatory chemokines found in this study support the hypothesis that subjects with past history of HAPE have higher baseline chronic inflammation which may contribute to HAPE susceptibility.

Positive Association of D Allele of ACE Gene With High Altitude Pulmonary Edema in Indian Population.

OBJECTIVE: High altitude pulmonary edema (HAPE) is a potentially fatal high altitude illness occurring as a result of hypobaric hypoxia with an unknown underlying genetic mechanism. Recent studies have shown a possible association between HAPE and polymorphisms in genes of the renin-angiotensin-aldosterone system (RAAS), which play a key role in sensitivity of an individual toward HAPE. METHODS: For the present investigation, study groups consisted of HAPE patients (HAPE) and acclimatized control subjects (rCON). Four single-nucleotide polymorphisms (SNPs) were genotyped using restriction fragment length polymorphism (RFLP) analysis in genes of the RAAS pathway, specifically, renin (REN) C(-4063)T (rs41317140) and RENi8-83 (rs2368564), angiotensin (AGT) M(235)T (rs699), and angiotensin-converting enzyme (ACE) insertion/deletion (I/D) (rs1799752). RESULTS: Only the I/D polymorphism of the ACE gene showed a significant difference between the HAPE and rCON groups. The frequency of the D allele was found to be significantly higher in the HAPE group. Arterial oxygen saturation levels were significantly lower in the HAPE group compared with the rCON group and also decreased in the I/D and D/D genotypes compared with the I/I genotype in these groups. The other polymorphisms occurring in the REN and AGT genes were not significantly different between the 2 groups. CONCLUSIONS: These findings demonstrate a possible association of the I/D polymorphism of the ACE gene with the development of HAPE, with D/D being the at-risk genotype.

Altitude-Related Illness.

Altitude-related illness occurs as a result of inadequate acclimatization. The mainstay of prevention is a slow, graded ascent profile which gives the body time to respond to a low-oxygen environment. The diagnosis of these conditions is often difficult in resource-limited environments, so history and a physical exam are key in identifying patients who will require descent and evacuation. Treatment modalities such as supplemental oxygen, portable hyperbaric chambers, and medications, are all temporizing measures until the patient can be safely evacuated to a lower elevation.

Preliminary study of identified novel susceptibility loci for HAPE risk in a Chinese male Han population.

High altitude pulmonary edema (HAPE) is a life-threatening form of non-cardiogenic pulmonary edema. In recent years, association studies have become the main method for identifying HAPE genetic loci. A genome-wide association study (GWAS) of HAPE risk-associated loci was performed in Chinese male Han individuals (164 HAPE cases and 189 healthy controls) by the Precision Medicine Diversity Array Chip with 2,771,835 loci (Applied Biosystems Axiom™). Eight overlapping candidate loci in CCNG2, RP11-445O3.2, NUPL1 and WWOX were finally selected. In silico functional analyses displayed the PPI network, functional enrichment and signal pathways related to CCNG2, NUPL1, WWOX and NRXN1. This study provides data supplements for HAPE susceptibility gene loci and new insights into HAPE susceptibility.

High-Altitude Pulmonary Edema Combined with Spontaneous Pneumomediastinum: A Case Report.

Background: High-altitude pulmonary edema (HAPE) is a serious life-threatening disease that occurs after rapid ascent to high altitude; its main early-stage presentations include fatigue, headache, low-grade fever, dyspnea, and cough. X-ray and computed tomography (CT) images show pulmonary shadows and patches, which may be localized (initial right lung field predomination) or generalized to the bilateral lung base. Case Presentation: In this report, we present a case of a 25-year-old man diagnosed with HAPE combined with spontaneous pneumomediastinum. After a quick descent and effective medical treatment, this patient made a full recovery. The case may provide helpful information for the prevention and treatment of this disease since an increased number of people, especially young men, currently travel and work at high altitudes. Conclusion: After accurate clinical diagnosis with the help of CT or X-ray, immediate descent and appropriate oxygen supplementation are the most effective treatments for HAPE at high altitude.

Three rare presentations of high-altitude pulmonary edema at a high-altitude clinic in the Everest region (4371 m): A case series.

Diagnosis of HAPE can be challenging when the presentation deviates from usual natural history. Point of care ultrasonography serves as a great diagnostic tool in such settings. An umbrella treatment could be beneficial during such scenarios.

Unique mutations in mitochondrial DNA and associated pathways involved in high altitude pulmonary edema susceptibility in Indian lowlanders.

High altitude pulmonary edema (HAPE) is a life threatening non-cardiogenic pulmonary edema that occurs in an otherwise healthy individuals travelling to altitude above 2500 m. Earlier studies have reported association of mutations in nuclear (nDNA) and mitochondrial DNA (mtDNA) with HAPE susceptibility. However, the molecular mechanisms involved in the pathobiology of HAPE have not been fully understood. The present study investigates the genetic predisposition to HAPE by analyzing the mtDNA mutations in HAPE susceptibles (n = 23) and acclimatized controls (n = 23) using next generation sequencing. Structural analysis of mutations was done using SWISS Model server and stability was determined using ΔΔG values. Meta-analysis of GSE52209 dataset was done to identify differentially expressed genes (DEGs) in HAPE susceptibles and acclimatized controls. Fourteen non-synonymous, conserved and pathogenic mutations were predicted using SIFT and PolyPhen scoring in protein coding genes, whereas six mutations in mt-tRNA genes showed association with HAPE (p ≤ 0.05). The structural analysis of these mutations revealed conformational changes in critical regions in Complexes I-V which are involved in subunit assembly and proton pumping activity. The protein-protein interaction network analysis of DEGs showed that HIF1α, EGLN2, EGLN3, PDK1, TFAM, PPARGC1α and NRF1 genes form highly interconnected cluster. Further, pathway enrichment analysis using DAVID revealed that "HIF-1 signaling", "oxidative phosphorylation" and "Metabolic pathways" had strong association with HAPE. Based on the findings it appears that the identified mtDNA mutations may be a potential risk factor in development of HAPE with the associated pathways providing mechanistic insight into the understanding of pathobiology of HAPE and sites for development of therapeutic targets.Communicated by Ramaswamy H. Sarma.

Morphological and functional findings in COVID-19 lung disease as compared to Pneumonia, ARDS, and High-Altitude Pulmonary Edema.

Coronavirus disease-2019 (COVID-19) may severely affect respiratory function and evolve to life-threatening hypoxia. The clinical experience led to the implementation of standardized protocols assuming similarity to severe acute respiratory syndrome (SARS-CoV-2). Understanding the histopathological and functional patterns is essential to better understand the pathophysiology of COVID-19 and then develop new therapeutic strategies. Epithelial and endothelial cell damage can result from the virus attack, thus leading to immune-mediated response. Pulmonary histopathological findings show the presence of Mallory bodies, alveolar coating cells with nuclear atypia, reactive pneumocytes, reparative fibrosis, intra-alveolar hemorrhage, moderate inflammatory infiltrates, micro-abscesses, microthrombus, hyaline membrane fragments, and emphysema-like lung areas. COVID-19 patients may present different respiratory stages from silent to critical hypoxemia, are associated with the degree of pulmonary parenchymal involvement, thus yielding alteration of ventilation and perfusion relationships. This review aims to: discuss the morphological (histopathological and radiological) and functional findings of COVID-19 compared to acute interstitial pneumonia, acute respiratory distress syndrome (ARDS), and high-altitude pulmonary edema (HAPE), four entities that share common clinical traits, but have peculiar pathophysiological features with potential implications to their clinical management.

hapE and hmg1 Mutations Are Drivers of cyp51A-Independent Pan-Triazole Resistance in an Aspergillus fumigatus Clinical Isolate.

Aspergillus fumigatus is a ubiquitous environmental mold that can cause severe disease in immunocompromised patients and chronic disease in individuals with underlying lung conditions. Triazoles are the most widely used class of antifungal drugs to treat A. fumigatus infections, but their use in the clinic is threatened by the emergence of triazole-resistant isolates worldwide, reinforcing the need for a better understanding of resistance mechanisms. The predominant mechanisms of A. fumigatus triazole resistance involve mutations affecting the promoter region or coding sequence of the target enzyme of the triazoles, Cyp51A. However, triazole-resistant isolates without cyp51A-associated mutations are frequently identified. In this study, we investigate a pan-triazole-resistant clinical isolate, DI15-105, that simultaneously carries the mutations hapEP88L and hmg1F262del, with no mutations in cyp51A. Using a Cas9-mediated gene-editing system, hapEP88L and hmg1F262del mutations were reverted in DI15-105. Here, we show that the combination of these mutations accounts for pan-triazole resistance in DI15-105. To our knowledge, DI15-105 is the first clinical isolate reported to simultaneously carry mutations in hapE and hmg1 and only the second with the hapEP88L mutation. IMPORTANCE Triazole resistance is an important cause of treatment failure and high mortality rates for A. fumigatus human infections. Although Cyp51A-associated mutations are frequently identified as the cause of A. fumigatus triazole resistance, they do not explain the resistance phenotypes for several isolates. In this study, we demonstrate that hapE and hmg1 mutations additively contribute to pan-triazole resistance in an A. fumigatus clinical isolate lacking cyp51-associated mutations. Our results exemplify the importance of and the need for a better understanding of cyp51A-independent triazole resistance mechanisms.

The Association of Methylation Level in the CYP39A1 Gene with High Altitude Pulmonary Edema in the Chinese Population.

Background: High altitude pulmonary edema (HAPE) is still the most common fatal disease at high altitudes. DNA methylation proceeds with an important role in HAPE progression. This study was designed to investigate the association between CYP39A1 methylation and HAPE. Methods: Peripheral blood samples were enrolled from 106 participants (53 HAPE patients and 53 healthy subjects) to study the association of CYP39A1 methylation with HAPE. DNA methylation site in the promoter region of CYP39A1 was detected by Sequenom MassARRAY EpiTYPER platform. Results: Probability analysis showed that the methylation probabilities of CYP39A1_1_CpG_5 and CYP39A1_3_CpG_21 are significant differences between the cases and controls (p< 0.05). The methylation level analysis indicated that CYP39A1_1_CpG_2.3.4, CYP39A1_5_CpG_6.7, and CYP39A1_5_CpG_9.10 were higher methylation in HAPE compared to the controls (p< 0.05). CYP39A1_3_CpG_21 and CYP39A1_4_CpG_3 exhibited a lower methylation level in HAPE than that in the controls (p< 0.05). The association analysis given that CYP39A1_1_CpG_2.3.4 (OR 2.56, p= 0.035), CYP39A1_5_CpG_6.7 (OR 3.99, p= 0.003), CYP39A1_5_CpG_9.10 (OR 3.99, p= 0.003), CYP39A1_5_CpG_16.17.18 (OR 2.53, p= 0.033), and CYP39A1_5_CpG_20 (OR 3.05, p= 0.031) are associated with an increased risk of HAPE. Whereas CYP39A1_1_CpG_5 (OR 0.33, p= 0.016) and CYP39A1_3_CpG_21 (OR 0.18, p= 0.005) have a protective role in HAPE. Besides, age-stratification analysis showed that CYP39A1_1_CpG_5 (OR 0.16, p= 0.014) and CYP39A1_3_CpG_21 (OR 0.08, p= 0.023) had a protective impact on HAPE in people aged ≤32 years. CYP39A1_5_CpG_6.7 (OR 6.70, p= 0.008) and CYP39A1_5_CpG_9.10 (OR 6.70, p= 0.008) were related to an increased susceptibility to HAPE aged >32 years. Moreover, the diagnostic value of CYP39A1_3_CpG_21 (AUC = 0.712, p< 0.001) was significantly better than other CpG sites. Conclusion: The methylation level of CYP39A1 was associated with a risk of HAPE in the Chinese population, which provided new perspective for preventing and diagnosing of HAPE.

Low-dose of caffeine alleviates high altitude pulmonary edema via regulating mitochondrial quality control process in AT1 cells.

Backgrounds: High-altitude pulmonary edema (HAPE) is a life-threatening disease without effective drugs. Caffeine is a small molecule compound with antioxidant biological activity used to treat respiratory distress syndrome. However, it is unclear whether caffeine plays a role in alleviating HAPE. Methods: We combined a series of biological experiments and label-free quantitative proteomics analysis to detect the effect of caffeine on treating HAPE and explore its mechanism in vivo and in vitro. Results: Dry and wet weight ratio and HE staining of pulmonary tissues showed that the HAPE model was constructed successfully, and caffeine relieved pulmonary edema. The proteomic results of mice lungs indicated that regulating mitochondria might be the mechanism by which caffeine reduced HAPE. We found that caffeine blocked the reduction of ATP production and oxygen consumption rate, decreased ROS accumulation, and stabilized mitochondrial membrane potential to protect AT1 cells from oxidative stress damage under hypoxia. Caffeine promoted the PINK1/parkin-dependent mitophagy and enhanced mitochondrial fission to maintain the mitochondria quality control process. Conclusion: Low-dose of caffeine alleviated HAPE by promoting PINK1/parkin-dependent mitophagy and mitochondrial fission to control the mitochondria quality. Therefore, caffeine could be a potential treatment for HAPE.