[This corrects the article DOI: 10.1371/journal.pone.0083895.].

Objective To analyze the risk factors for chronic mountain sickness(CMS)in young male migrants living in high-altitude areas and to construct a diagnostic model and evaluate its diagnostic efficacy.Methods From June 10 to December 29,2023,a cross-sectional study was conducted on young male migrants subjected with convenience sampling who had been living in high-altitude areas(4 500～5 000 m)for 6 months or longer.Their demographic data were collected and blood samples were collected for laboratory test.According to the Qinghai Score for Chronic Mountain Sickness,they were divided into CMS group and non-CMS group.Then the participants were randomly divided into a training set and a test set in a ratio of 8∶2.Independent risk factors for CMS occurrence were screened out,through random forest variable importance ranking,univariate and multivariable logistic regression analysis,and a diagnostic model was constructed based on these factors.Receiver operating characteristic(ROC)curve analysis,calibration curve analysis,clinical decision curve analysis,and influence curve analysis were used to comprehensively evaluate the diagnostic performance of the model.Results According to the inclusion and exclusion criteria,308 out of 376 participants were finally subjected,and 17.53%of them were diagnosed with CMS.The major clinical symptoms of the CMS patients were dyspnea or palpitations(79.63%)and sleep disorders(85.19%).Further analysis revealed that creatine kinase-MB/creatine kinase(CK-MB/CK,OR=2.17,95%CI:1.43～3.28),high-altitude residence time(OR=2.44,95%CI:1.08～5.54),and body mass index(BMI,OR=1.62,95%CI:1.05～2.50)were 3 major independent risk factors for CMS.The area under the curve(AUC)value of the CMS diagnostic model in the training set and test set was 0.821(95%CI:0.756～0.886)and 0.821(95%CI:0.700～0.944),the specificity was 66.30%and 73.90%,the sensitivity was 89.50%and 81.20%,respectively,indicating good discrimination ability.Hosmer-Lemeshow goodness-of-fit test showed consistency between predicted results and actual observations(χ2=10.029,P=0.263;χ2=4.477,P=0.812).Clinical decision curve analysis demonstrated that within the threshold probability range from 0.1 to 0.7,the net benefit of the model exceeded both full intervention and no intervention strategies.The influence curve analysis showed high consistency between the model predictions and actual incidence when the threshold probability exceeded 0.4.These two analyses together confirmed the clinical application value of the model.Conclusion CK-MB/CK,high-altitude residence time and BMI are independent risk factors for CMS,and their diagnostic model helps identify potential individuals at risk for CMS.Early intervention can prevent the harm of CMS to the health of young men migrating to high-altitude areas.

Xiaoying Zhou, Wenting Su, Quanwei Bao, Yu Cui, Xiaoxu Li, Yidong Yang, Chengzhong Yang, Chengyuan Wang, Li Jiao, Dewei Chen, and Jian Huang. Nitric oxide ameliorates the effects of hypoxia in mice by regulating oxygen transport by hemoglobin. High Alt Med Biol. 00:00-00, 2024.-Hypoxia is a common pathological and physiological phenomenon in ischemia, cancer, and strenuous exercise. Nitric oxide (NO) acts as an endothelium-derived relaxing factor in hypoxic vasodilation and serves as an allosteric regulator of hemoglobin (Hb). However, the ultimate effects of NO on the hematological system in vivo remain unknown, especially in extreme environmental hypoxia. Whether NO regulation of the structure of Hb improves oxygen transport remains unclear. Hence, we examined whether NO altered the oxygen affinity of Hb (Hb-O2 affinity) to protect extremely hypoxic mice. Mice were exposed to severe hypoxia with various concentrations of NO, and the survival time, exercise capacity, and other physical indexes were recorded. The survival time was prolonged in the 5 ppm NO (6.09 +/- 1.29 minutes) and 10 ppm NO (6.39 +/- 1.58 minutes) groups compared with the 0 ppm group (4.98 +/- 1.23 minutes). Hypoxia of the brain was relieved, and the exercise exhaustion time was prolonged when mice inhaled 20 ppm NO (24.70 +/- 6.87 minutes vs. 20.23 +/- 6.51 minutes). In addition, the differences in arterial oxygen saturation (SO2%) (49.64 +/- 7.29% vs. 42.90 +/- 4.30%) and arteriovenous SO2% difference (25.14 +/- 8.95% vs. 18.10 +/- 6.90%) obviously increased. In ex vivo experiments, the oxygen equilibrium curve (OEC) left shifted as P50 decreased from 43.77 +/- 2.49 mmHg (0 ppm NO) to 40.97 +/- 1.40 mmHg (100 ppm NO) and 38.36 +/- 2.78 mmHg (200 ppm NO). Furthermore, the Bohr effect of Hb was enhanced by the introduction of 200 ppm NO (-0.72 +/- 0.062 vs.-0.65 +/- 0.051), possibly allowing Hb to more easily offload oxygen in tissue at lower pH. The crystal structure reveals a greater distance between Asp94 beta-His146 beta in nitrosyl -Hb(NO-Hb), NO-Hb beta CSO93, and S-NitrosoHb(SNO-Hb) compared to tense Hb(T-Hb, 3.7 & Aring;, 4.3 & Aring;, and 5.8 & Aring; respectively, versus 3.5 & Aring; for T-Hb). Moreover, hydrogen bonds were less likely to form, representing a key limitation of relaxed Hb (R-Hb). Upon NO interaction with Hb, hydrogen bonds and salt bridges were less favored, facilitating relaxation. We speculated that NO ameliorated the effects of hypoxia in mice by promoting erythrocyte oxygen loading in the lung and offloading in tissues.

Erythrocytosis moderately enhances the oxygen-carrying capacity of the blood and is considered a characteristic response of individuals adapting from low-altitude regions to high-altitude regions. Nevertheless, erythrocytosis can also turn excessive and result in maladaptive syndromes, such as high altitude polycythemia (HAPC). The increased differentiation or proliferation of erythroid cells in the bone marrow may be a crucial factor leading to accumulation of peripheral erythroid cells. However, the mechanism of erythroid regulation within the bone marrow of high-altitude erythrocytosis remains insufficiently systematically observed. We utilized single-cell transcription sequencing to characterize bone marrow cells following chronic hypoxic exposure and found that bone marrow erythrocytosis is associated with the accumulation of Baso-E, Poly-E, and Ortho-E cells at the terminal stage of erythroid lineage differentiation. Through analysis of differential gene expression and localization in differentiated cells within the erythroid lineage, we confirmed that DDIT4 expression was localized in advanced differentiated erythroblast including Baso-E, Poly-E and Ortho-E, its expression was significantly enhanced by hypoxia exposure. We demonstrated that overexpression of DDIT4 could promote K562 cell differentiation, and through the IP pull-down interaction protein profile, we found that DDIT4 might participate in regulating the cell cycle by interacting with SIPA1 to promote the proliferation of erythroid cells and may be involved in HAPC.

Li, Xiaoxu, Zhijun Pu, Gang Xu, Yidong Yang, Yu Cui, Xiaoying Zhou, Chenyuan Wang, Zhifeng Zhong, Simin Zhou, Jun Yin, Fabo Shan, Chengzhong Yang, Li Jiao, Dewei Chen, and Jian Huang. Hypoxia-induced myocardial hypertrophy companies with apoptosis enhancement and p38-MAPK pathway activation. High Alt Med Biol. 00:00-00, 2024.Background: Right ventricular function and remodeling are closely associated with symptom severity and patient survival in hypoxic pulmonary hypertension. However, the detailed molecular mechanisms underlying hypoxia-induced myocardial hypertrophy remain unclear.Methods: In Sprague-Dawley rats, hemodynamics were assessed under both normoxia and hypobaric hypoxia at intervals of 7 (H7), 14 (H14), and 28 (H28) days. Morphological changes in myocardial tissue were examined using hematoxylin and eosin (HE) staining, while myocardial hypertrophy was evaluated with wheat germ agglutinin (WGA) staining. Apoptosis was determined through TUNEL assays. To further understand the mechanism of myocardial hypertrophy, RNA sequencing was conducted, with findings validated via Western blot analysis.Results: The study demonstrated increased hypoxic pulmonary hypertension and improved right ventricular diastolic and systolic function in the rat models. Significant elevations in pulmonary arterial systolic pressure (PASP), mean pulmonary arterial pressure (mPAP), right ventricular mean pressure (RVMP), and the absolute value of +dp/dtmax were observed in the H14 and H28 groups compared with controls. In addition, right ventricular systolic pressure (RVSP), -dp/dtmax, and the mean dp/dt during isovolumetric relaxation period were notably higher in the H28 group. Heart rate increased in the H14 group, whereas the time constant of right ventricular isovolumic relaxation (tau) was reduced in both H14 and H28 groups. Both the right heart hypertrophy index and the heart weight/body weight ratio (HW/BW) were elevated in the H14 and H28 groups. Myocardial cell cross-sectional area also increased, as shown by HE and WGA staining. Western blot results revealed upregulated HIF-1 alpha levels and enhanced HIF-2 alpha expression in the H7 group. In addition, phosphorylation of p38 and c-fos was augmented in the H28 group. The H28 group showed elevated levels of Cytochrome C (Cyto C), whereas the H14 and H28 groups exhibited increased levels of Cleaved Caspase-3 and the Bax/Bcl-2 ratio. TUNEL analysis revealed a rise in apoptosis with the extension of hypoxia duration in the right ventricle.Conclusions: The study established a link between apoptosis and p38-MAPK pathway activation in hypoxia-induced myocardial hypertrophy, suggesting their significant roles in this pathological process.

Objective To analyze the differential expressed genes (DEGs) in the lung tissues of rat model of high altitude pulmonary edema (HAPE) by using microarray analysis in order to provide new clues for molecular mechanism of HAPE. Methods Healthy male SD rats (8 weeks old, weighing 200±20 g) were randomized into normoxia control (NC) group, lipopolysaccharide (LPS) group, hypoxia group and hypoxia +low-dose LPS (HL) group. The rats of the LPS group and HL group were injected with 0.1 mL 0.05% LPS per 100 g body weight, and those of the NC group and the hypoxia group were administered with an equivalent volume of normal saline. The rats of the hypoxia group and the HL group were housed in a hypobaric chamber simulating an altitude of 5 000 m, and those of the NC group and the LPS group were raised simultaneously outside of the chamber. The wet/dry mass ratio (WDR) of lung tissue and total protein content in bronchoalveolar lavage fluid (BALF) were measured, and the histopathological changes of lung tissue was observed using HE staining. The total RNA was extracted from the lung tissues, and the mRNA expression profile was obtained with Affymetrix microarray followed by Gene Ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis with Metascape (http://metascape.org). Results The rats of the HL group showed significant congestion, edema, and widened alveolar septa. Compared with the NC group, the HL group had significantly increased lung WDR (P<0.01) and total protein content in BALF (P<0.05). Gene expression analysis revealed that there were 79 genes up-regulated and 59 genes down-regulated in the hypoxia group, 473 genes up-regulated and 695 genes down-regulated in the LPS group, and especially, 669 genes up-regulated and 1 253 genes down-regulated in the HL group. GO and KEGG pathway analyses revealed that the upregulated genes in the HL group were mainly enriched in biological processes, such as cytokine mediated signaling pathways, response to IL-1, regulation of inflammatory response, as well as signaling pathways, including cytokine-cytokine receptor interactions, TNF, NF-κB, IL-17, complement and coagulation cascades, etc. The down-regulated genes were mainly enriched in biological processes, such as extracellular matrix organization, regulation of endothelial cell migration, cell substrate adhesion, as well as signaling pathways, such as focal adhesion, Wnt, cGMP-PKG, PI3K-Akt, Rap1, etc. The mRNA expression of NF-κB, TNF-α, IL-1β and IL-6 was significantly up-regulated in the lung tissue of the HL group (P<0.01). Conclusion Hypoxia+low-dose LPS is an effective procedure to establish a reliable model for HAPE in rats. Hypoxia can significantly aggravate LPS-induced inflammation and immune response, enhance the expression of inflammatory mediators, and thus promote the pathogenesis of HAPE.

ObjectiveTo investigate the mechanism of hypoxia-induced free iron reduction in mouse pulmonary artery smooth muscle cells（PASMCs）and its role in the proliferation of PASMCs and pulmonary vascular remodeling.Methods①Primary mouse PASMCs were cultured and divided into normoxic group（C）, normoxic ferric ammonium citrate group（C+FAC）, normoxic rapamycin group（C+R）, hypoxic group（H）, hypoxic ferric ammonium citrate group（H+FAC）and hypoxic rapamycin group（H+R）. The C, C＋FAC and C＋R groups were incubated in normoxic（21% O2）enviroment for 48 h. The H, H+FAC and H+R groups were incubated in hypoxic（1% O2）environment for 48 h. The C+FAC and H+FAC groups were treated with ferrous ammonium citrate（FAC）, and the C+R and H+R groups were treated with rapamycin（R）. Cell proliferation was detected with CCK-8 assay and EdU proliferation assay. The content of intracellular free iron was measured by FerroOrange staining. The protein levels of iron regulatory proteins（IRPs）, transferrin receptor（TFR）, ferroportin（FPN）and ferritin heavy chain（FTH）were detected with Western blotting. ②Twenty-four C57/BL6N mice（male, 6 weeks old, weighting 18~22 g）were divided into normoxic group（C-4W）, normoxic high-iron diet group（C+HID-4W）, hypoxic group（H-4W）and hypoxic high-iron diet group（H+HID-4W）（n=6）. The H-4W and H+HID-4W groups were placed in a low-pressure hypoxic environment at a simulated altitude of 5 000 m for 4 weeks. Right heart function, right ventricular systolic pressure, and pulmonary vascular remodeling in each group were observed and measured.ResultsCompared with C group, significantly enhanced proliferation（P<0.01）, reduced intracellular free iron content（P<0.01）, and up-regulated protein level of FTH were observed in the PASMCs of H group（P<0.01）. Compared with H group, the free iron content was obviously increased（P<0.01）and cell proliferation was decreased in H+FAC group（P<0.01）. The H+R group had notably increased free iron content（P<0.01）, decreased cell proliferation（P<0.05）, and reduced protein level of FTH when compared with H group（P<0.05）. Compared with H-4W group, the mice in the H+HID-4W group showed significantly improved right heart function（P<0.01）, lower right ventricular systolic pressure（P<0.05）, reduced right heart hypertrophy（P<0.01）, and inhibited pulmonary artery thickening（P<0.01）.ConclusionHypoxia mediates the reduction of free iron by inhibiting the ferritinophagy pathway, and thus promotes the proliferation of PASMCs and pulmonary artery remodeling.

Right ventricular remodeling and its function are closely related to the symptom severity and survival of hypoxia pulmonary hypertension, but molecular mechanisms of cardiomyocyte hypertrophy and myocardial injury remain unclear. It evaluated the cardiac function (by right cardiac catheterization to measure right ventricular systolic pressure and mean pulmonary artery pressure), myocardial tissue morphology（Haematoxylin and Eosin）, myocardial hypertrophy (Wheat Germ Agglutinin Staining), then RNA sequencing was applied to explore the mechanism, which results were verified by western blot in final. Hypoxia developed pulmonary hypertension, right ventricular diastolic and systolic functions were enhanced in rats, such as the mean pulmonary artery pressure, systolic pressure of pulmonary artery, the max pressure of right ventricular, the mean right ventricular pressure, and the heart rate was significantly higher than that in control. We found that Hif-1 signaling pathway and p38-MAPK signaling pathway have been activated by hypoxia, and cardiomyocyte apoptosis also aggravated in the right ventricular, which might be one cause of cardiomyocyte hypertrophy and myocardial injury, and targeted intervention might be one potential prevention for cardiomyocyte hypertrophy and myocardial injury induced by hypoxia.

Evidence is mounting that sinomenine and peroxisome proliferator-activated receptor β/δ (PPARβ/δ) are effective against lipopolysaccharide (LPS)-induced acute lung injury (ALI) via anti-inflammatory properties. However, it is unknown whether PPARβ/δ plays a role in the protective effect of sinomenine on ALI. Here, we initially observed that preemptive administration of sinomenine markedly alleviated lung pathological changes, pulmonary edema and neutrophil infiltration, accompanied by inhibition of the expression of the pro-inflammatory cytokines Tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6), which were largely reversed following the addition of a PPARβ/δ antagonist. Subsequently, we also noticed that sinomenine upregulated adenosine A2A receptor expression in a PPARβ/δ-dependent manner in LPS-stimulated bone marrow-derived macrophages (BMDMs). Further investigation indicated that PPARβ/δ directly bound to the functional peroxisome proliferator responsive element (PPRE) in the adenosine A2A receptor gene promoter region to enhance the expression of the adenosine A2A receptor. Sinomenine was identified as a PPARβ/δ agonist. It could bind with PPARβ/δ, and promote the nuclear translocation and transcriptional activity of PPARβ/δ. In addition, combined treatment with sinomenine and an adenosine A2A receptor agonist exhibited synergistic effects and better protective roles than their single use against ALI. Taken together, our results reveal that sinomenine exerts advantageous effects on ALI by activating of PPARβ/δ, with the subsequent upregulation of adenosine A2A receptor expression, and provide a novel and potential therapeutic application for ALI.

Objective To explore the role and mechanism of DNase 2α on hypoxia-induced proliferation of rat pulmonary artery smooth muscle cells (RPASMCs). Methods Primary RPASMCs were cultured with 3%O2 to establish a hypoxia-induced cell proliferation model. Small interference RNA (siRNA) was used to decrease the expression of Dnase2a, and corresponding plasmids were employed to up-regulate the expression of Dnase2a and Hif1a. Cell proliferation was induced by exogenous mitochondrial DNA (mtDNA). Proline hydroxylase inhibitor ROXA was adopted to enhance the expression of HIF-1α. The proliferation of cells in each group was detected by MTS assay, the mRNA level of Dnase2a was detected by qPCR, and the protein levels of DNase 2α, proliferating cell nuclear antigen (PCNA) and cell cycle protein D1 (Cyclin D1) were detected by Western blotting. Results Hypoxia induced the proliferation of RPASMCs and up-regulated the expression of DNase 2α. siRNA significantly decreased the expression of Dnase2a (P < 0.05) and promoted the hypoxia-induced proliferation of RPASMCs (P < 0.05), and the protein expression of PCNA and Cyclin D1 was up-regulated (P < 0.05). Overexpression of Dnase2a up-regulated the expression of Dnase2a (P < 0.05) and inhibited the proliferation of RPASMCs induced by hypoxia (P < 0.05). Exogenous mtDNA also promoted the proliferation of RPASMCs, while, overexpression of DNase 2α inhibited the above proliferation (P < 0.05). Overexpression of Hif1a or proline hydroxylase inhibitor ROXA could significantly up-regulate the protein expression of HIF-1α and DNase 2α (P < 0.05). Conclusion DNase 2α inhibits the proliferation of RPASMCs induced by hypoxia or mtDNA, whose expression induced by hypoxia is associated with HIF-1α.

目的 通过对久居高海拔地区人群进行慢性高原病(CMS)调查,并与10年前调查数据进行比较分析,了解CMS患病情况及10年前后变化情况,为CMS的预防和诊断提供依据.方法 应用CMS调查量表对2019年3300～5400 m海拔地区的218名受试对象进行调查,分析其患病情况,并与2009年相同海拔范围的510名受试对象的调查数据进行比较,分析两批数据间的差异.结果 2019年调查对象的CMS患病率(15.60％)较2009年(31.18％)显著降低;在2019年调查对象中,低氧血症、呼吸困难、静脉曲张、局部感觉异常、头痛、耳鸣和血红蛋白浓度升高(≥21 g/dl)的发生率显著降低,紫绀、静脉曲张、局部感觉异常和头痛的评分显著降低,但在CMS患病人群中,睡眠障碍评分显著增高;CMS患病风险随累计高原生活时间显著增高.结论 与2009年相比,2019年高原人群健康水平显著提高,可能与近年来高原人群健康关注度及生活水平提高有关;在各项症状反应评分中,睡眠障碍是影响居民健康的重要指标,在CMS预防和诊断过程中值得重点关注;科学控制高原停留时间,是减少CMS患病的关键手段.

Objective To investigate the role and possible mechanism of mitochondrial DNA (mtDNA) release in the proliferation of rat pulmonary arterial smooth muscle cells (RPASMCs) induced by hypoxia. Methods ① RPASMCs were divided into normoxia group, hypoxia 24-hour group and hypoxia 48-hour group (n=3 for each groups), and the latter 2 groups were exposed to 1%O2 for 24 or 48 h respectively. ② Cyclosporine A (CsA) was used to inhibit the mitochondrial permeability transition pore (MPTP), and then the RPASMCs were divided into normoxia, simple hypoxia 48-hour and hypoxia 48-hour+CsA groups (n=3 for each). ③ SiRNA was adopted to knockdown the expression of stimulator of interferon genes (STING), and the cells were subsequently divided into normoxia+NC, hypoxia 48-hour+NC and hypoxia 48-hour+si-STING (n=3 for each). ④ The proliferation of the cells was measured by CCK-8 assay. The expression of cyclic GMP-AMP synthase (cGAS), STING and proliferating cell nuclear antigen (PCNA) at mRNA and protein levels was detected by RT-qPCR and Western blotting, respectively. Cytosolic mtDNA release was determined by qPCR, and the level of C-X-C motif chemokine ligand 10 (CXCL10) in the culture supernatant was tested by ELISA. Results Hypoxia induced RPASMCs to release mtDNA (P < 0.01), significantly up-regulated the expression of cGAS, STING and PCNA (P < 0.05), enhanced the secretion of CXCL10 (P < 0.01), and thus promoted the proliferation of RPASMCs (0.44±0.02 vs 0.72±0.03, P < 0.05). However, inhibition of MPTP blocked mtDNA release (P < 0.01), down-regulated cGAS, STING and PCNA (P < 0.01), and decreased CXCL10 level (P < 0.01) and hypoxia-induced proliferation of RPASMCs (0.74±0.12 vs 0.43±0.06, P < 0.01). The knockdown of STING also suppressed PCNA expression (P < 0.05), reduced CXCL10 secretion (P < 0.01), and inhibited the proliferation of RPASMCs (0.68±0.03 vs 0.58±0.01, P < 0.01). Conclusion Hypoxia can induce smooth muscle cells to release mtDNA and promote the proliferation of RPASMCs, which may be related to the activation of the cGAS-STING pathway.

Pulmonary arterial hypertension (PAH) is an incurable disease with high mortality. Chemerin has been found to be associated with pulmonary hypertension (PH). However, the specific role of chemerin in mediating PH development remains unclear. This study aimed to elucidate the regulatory effects and the underlying mechanism of chemerin on PH and to investigate the expression levels of chemerin protein in plasma in PAH patients. In vivo, two animal models of PH were established in rats by monocrotaline (MCT) injection and hypoxia. We found that the expression levels of chemerin and its receptor, chemokine-like receptor 1 (CMKLR1), were significantly upregulated in the lungs of PH rats. Primary cultured pulmonary arterial smooth muscle cells [(PASMCs) (isolated from pulmonary arteries of normal healthy rats)] were exposed to hypoxia or treated with recombinant human chemerin, we found that CMKLR1 expression was upregulated in PASMCs in response to hypoxia or chemerin stimulation, whereas the exogenous chemerin significantly promoted the migration and proliferation of PASMCs. Notably, the regulatory effects of chemerin on PASMCs were blunted by PD98059 (a selective ERK1/2 inhibitor). Using enzyme linked immunosorbent assay (ELISA), we found that the protein level of chemerin was also markedly increased in plasma from idiopathic pulmonary arterial hypertension (IPAH) patients compared to that from healthy controls. Moreover, the diagnostic value of chemerin expression in IPAH patients was determined through receiver operating characteristic (ROC) curve analysis and the result revealed that area under ROC curve (AUC) for plasma chemerin was 0.949. Taken together, these results suggest that chemerin exacerbates PH progression by promoting the proliferation and migration of PASMCs via the ERK1/2 signaling pathway, and chemerin is associated with pulmonary hypertension.

The treatment of persistent erythema and rosacea flushing is extremely challenging, especially for patients with anxiety. The aim of this study was to verify the efficacy of carvedilol in rosacea patients with persistent erythema and flushing. A total of 156 patients were randomized to use oral carvedilol 5 mg bid (twice per day) (n = 105) or topical brimonidine (n = 51) for a 10-week period with 6 weeks of follow-up. Both the efficacy of carvedilol and the status of anxiety/depression were analyzed by patient self-assessment (PSA), clinician erythema assessment (CEA), generalized anxiety disorder (GAD-7), and patient health questionnaire-9 (PHQ-9). Our study found that carvedilol exerted a dramatic reduction in CEA/PSA scores and sting/burning sensation scores in comparison to topical brimonidine. Additionally, carvedilol treatment dramatically improved telangiectasia, erythema, and pigmentation with no obvious side effects. Patients with carvedilol treatment showed an improvement of depression/anxiety, as reflected by lower GAD-7 and PHQ-9 scores than patients with topical brimonidine. Notably, we found carvedilol treatment had better outcomes among patients under 30 years of age with rosacea younger than 30 years old. Conclusively, our findings reveal that carvedilol could quickly and effectively improve facial erythema, which might stem from the improved the status of anxiety/depression.

Monocyte subsets, including classical, intermediate and non-classical monocytes, are involved in the pathogenesis of inflammatory or autoimmune diseases. The pathogenic role of monocytes in the peripheral blood mononuclear cells (PBMCs) of patients with rosacea remains unclear. This study aimed to assess frequencies of monocyte subsets in PBMCs from rosacea patients before and after clinical treatment. We applied flow cytometry to examine frequencies of monocyte subsets in 116 patients with rosacea，while patients with 26 systemic lupus erythematosus (SLE), 28 acne and 42 normal healthy subjects without skin problems (HC) were recruited as controls. Expression of CCR2 on monocytes and plasma levels of CCL2, HMGB-1, IL-1β and TNF-α were measured in HC and rosacea patients before and after treatment. The frequency of classical monocytes, but not intermediate or non-classical monocytes, was higher in rosacea as compared with HC, which decreased after treatment. Frequencies of monocyte subsets showed no gender difference, while increased with age in patients but not in HC. Frequencies of classical monocytes in patients with erythromatotelangiectatic rosacea (ETR) and ETR-papulopaustula rosacea (PPR) overlap were significantly higher than HC or patients with only PPR or phytomatous rosacea (PhR). There was a significant higher expression of CCR2 in classical monocytes, with higher plasma levels of CCL2, HMGB-1, IL-1β and TNF-α in patients than in HC, which all significantly decreased after treatment. Our data indicated a possible association between abnormal classical monocytes frequencies and rosacea.

BackgroundChronic mountain sickness (CMS), is a common disease occurred to people who migrate to plateau. Current CMS studies in different periods or areas have poor comparability due to the inconsistent diagnosis methods. Here we carried out a comparative study of the CMS prevalence in the year 2019 and 2009, to provide evidence for the prevention and diagnosis of CMS. Methods The Qinghai CMS Scoring System (Qinghai standard) was used to investigate the subjects who lived for at least months in the 3300-5400 m altitude area in 2019 and 2009, respectively. Their prevalence and symptom scores were also analyzed and statistically compared.ResultsThe prevalence of CMS in 2019 survey subjects (15.60%) was significantly lower than that in 2009 (31.18%). The prevalence of dyspnea, venous dilatation, paresthesia, headache, tinnitus, and hemoglobin concentration reached 21g/dL or above decreased significantly among the survey subjects in 2019. The scores of cyanosis, venous dilatation, paresthesia, and headache significantly decreased in the 2019 survey subjects. But among the CMS patients, the sleep disturbance scores of the 2019 survey subjects increased significantly. ConclusionCompared to 2009, the health level of high altitude living population in 2019 has been significantly improved, indicating that the sleep research on high-altitude living population and the application of high altitude oxygen therapy has been effective in the past ten years. Among the CMS associated symptoms, sleep disturbance is an important indicator for the prevention and diagnosis of CMS, which deserves special attention.

EPAS1 (endothelial PAS domain protein 1), as the major effect gene for the adaptation to chronic hypoxia, is required for hypoxic pulmonary hypertension (HPH). Downregulated EPAS1 ameliorates the development of HPH. We confirmed that EPAS1-specific inhibitor PT2385 ameliorated HPH features, as demonstrated by right ventricle hypertrophy, right ventricular systolic pressure, and pulmonary vascular remodeling. However, the mechanism of EPAS1 in HPH pathogenesis remains unclear. RNA sequencing in human pulmonary artery endothelial cells with EPAS1 knockdown identified EPAS1-regulated genes, including ICAM1 (intercellular adhesion molecule 1), which created a proinflammatory perivascular microenvironment associated with HPH by elevating leukocyte adhesion to the vascular endothelium. Chromatin immunoprecipitation assays revealed that EPAS1 directly bound to ICAM1 promoter. The long noncoding RNA small nucleolar RNA host gene 5 (SNHG5), significantly increased in acute exacerbation period of chronic obstructive pulmonary disease and hypoxic human pulmonary artery endothelial cells, also contributed to the regulation of ICAM1 expression. Endothelial-specific deletion of Snhg5 also rescued HPH in mice. Overexpression of EPAS1 or SNHG5 enhanced, while the depletion of EPAS1 or SNHG5 attenuated, ICAM1 transactivation. SNHG5 was directly regulated by EPAS1, and interestingly, the upregulated SNHG5 could further enhance the levels of EPAS1, which consequently led to hypoxia-induced ICAM1 transactivation. RNA pull-down assay followed by high-throughput sequencing demonstrated that miR-625-5p could bind to SNHG5. Manipulating miR-625-5p altered the levels of EPAS1 during hypoxia. Our data showed a positive feed-forward exists between EPAS1 and SNHG5 signaling during hypoxia-induced ICAM1 transactivation in endothelial cells. Targeting EPAS1 and SNHG5 may provide promising strategies for the prevention of HPH.

Objective To investigate the role of SRY-Box transcription factor 6 (SOX6)-suppressor of cytokine signaling 3 (SOCS3) on hypoxia-induced proliferation of human pulmonary artery smooth muscle cells (HPASMCs) and explore the possible mechanism. Methods ① The HPASMCs were treated with 4% O2 for 24 h or 48 h. ② siRNA was used to decrease the expression of SOX6 (si-SOX6-NC, si-SOX6-1, si-SOX6-2, si-SOX6-3) and SOCS3 (si-SOCS3-NC, si-SOCS3-1, si-SOCS3-2) in the cells. ③The HPASMCs with stable SOX6 overexpression induced by transfection with a lentiviral vector were exposed to hypoxia for 48 h, with the cells cultured in normoxia condition, or simple hypoxia condition as control. ④CCK-8 assay was used to testify the proliferation of the above groups of cells. The expression of SOX6, SOCS3, proliferating cell nuclear antigen (PCNA) and phosphorylated-signal transduction and activators of transcription 3 (p-STAT3) at mRNA and protein levels were detected by RT-qPCR and Western blotting, respectively. Results Hypoxia decreased the expression levels of SOX6 and SOCS3 (P<0.01), induced the proliferation of HPASMCs and up-regulated the levels of p-STAT3 and PCNA (P<0.05). Under normoxia condition, the reduction of SOX6 or SOCS3 not only significantly increased the proliferation of HPASMCs (P<0.05) butalso the levels of p-STAT3 and PCNA (P<0.01). Under hypoxia, overexpression of SOX6 obviously suppressed hypoxia-induced proliferation and the expression levels of p-STAT3 and PCNA (P<0.01). Conclusion SOX6-SOCS3 can suppress the hypoxia-induced proliferation of HPASMCs. Its mechanisms may be related to the inhibition of STAT3 signaling pathway.

Objective To investigate the damage of seminiferous tubules in mice exposed to hypoxia and the effects of hypoxia on apoptosis of mouse spermatocytes in the seminiferous tubules. Methods Forty 3-week-old male Balb/c mice were randomly assigned into a normoxia group (housed in a normoxic condition at an altitude of 300 m) and 3 hypoxia groups exposed to hypoxia for 15, 30 or 60 d in a hypobaric chamber simulating the condition at an altitude of 6 000 m. After hypoxic exposures, the mice were euthanized and the testicular tissues were examined for pathological changes in the seminiferous tubules using HE and TUNEL staining. A mouse spermatocyte-derived cell line, GC-2spd, was also cultured in a normoxic condition or a hypoxic condition (1% O2 and 5% CO2) for 48, 60, or 72 h, and the cell apoptosis was detected using flow cytometry and TUNEL staining and by examining LDH, caspase-3, caspase-8, and caspase-9 levels in the culture medium. Results The apoptotic rates of the spermatocytes in the testicular seminiferous tubules of the mice increased significantly after hypoxic exposure for 15, 30 and 60 d as compared with the apoptosis rate of (4.6±1.4)% in the normoxia group (P < 0.01). In cultured GC-2spd cells, hypoxic exposure for 48, 60 and 72 h also significantly increased the cell apoptotic rate to (15.43±1.47)%, (44.10±14.10)% and (63.36±12.74)%, as compared with the rates of (4.18±1.40)%, (5.45%±2.30)%, and (14.47±8.21)% in the normoxia group, respectively (P < 0.01). Microscopically, the numbers of apoptotic spermatocytes per field were 22±3, 55±5, and 82±12 in the hypoxia group at 48, 60 and 72 h, respectively, significantly greater than those in the normoxia group (5±1, 8±2, and 15±4, respectively; P < 0.01). The absolute value of LDH activity in cultured GC-2spd cells at 48 h was significantly higher in the hypoxia group than in the normoxia group (1.28±0.18 vs 0.48±0.09, P < 0.01); the values of caspase-3/8/9 in the hypoxia group at 48 h were 12.20±0.40, 22.73±0.60, and 10.90±0.40, respectively, significantly higher than those in the normoxia group (7.67±0.45, 16.20±0.56, and 7.03±0.25, respectively, P < 0.01). Conclusion Exposure to hypoxia simulating the condition at an altitude of 6 000 m for 15 d can cause decreased spermatogenesis and increased apoptosis of the spermatogenic cells in mice, suggesting that spermatocyte apoptosis is one of the mechanisms by which hypobaric hypoxia reduces spermatogenesis.

High-altitude physiology is a basic and core discipline of high-altitude medicine and also a required course for undergraduates majoring in high-altitude medicine. At present, high-altitude physiology teaching mainly adopts the traditional teaching mode, with a monotony teaching method. MOOC is a newly emerging online course model with advanced educational concepts. Under the background of the current military reform, the MOOC combined with the traditional teaching mode in high-altitude teaching can not only comprehensively improve the teaching quality and learning ability, but also effectively enhance the competency of students in high-altitude military medicine.