Hypoxia Induces Alterations in the Circadian Rhythm in Patients with Chronic Respiratory Diseases

Assessment of continuous positive airway pressure effect on the circadian clock signaling pathway in obstructive sleep apnea patients

Obstructive sleep apnea (OSA) is associated with circadian rhythm dysregulation plausibly through affecting clock genes. The study's purpose was to investigate the effect of one-night continuous positive airway pressure treatment (CPAP treatment) on circadian clock genes: BMAL1, CLOCK, CRY1, and PER1 at mRNA and protein levels. The study included 30 OSA patients, who underwent diagnostic polysomnography (PSG) and next a one-night effective CPAP treatment with PSG monitoring (CPAP). The blood was collected in the evening before and the morning after PSG and CPAP. Protein levels and mRNA expression were measured using ELISA and qRT-PCR, respectively. The increase in PER1 expression was observed in the morning after compared to the evening before CPAP (p = 0.005); additionally, PER1 protein level decreased in the morning after CPAP compared to the morning after PSG (p = 0.035). In CLOCK protein levels significant changes were observed: an increase in the morning after CPAP compared to the morning after PSG (p = 0.049), an increase in the morning after CPAP compared to the evening before (p = 0.006), and an increase in difference between the morning after and evening before CPAP vs. difference between morning after and evening before PSG (p = 0.012). Obtained results suggest that even short-term effective CPAP treatment might reverse circadian clock signaling pathway disruption in OSA.

Clinical Characteristics of Postpartum Women With Hypoxia: A Retrospective Analysis of 92 Cases

Purpose

Postpartum hypoxia is a significant concern among clinicians due to its association with fatal diseases such as amniotic fluid embolism. This study analyzed the clinical characteristics of patients with different etiologies of postpartum hypoxia.

Patients and Methods

Ninety-two postpartum cases with hypoxia, defined as oxygen saturation (SpO2) < 95% within 48 h postpartum without supplemental oxygen inhalation, and 100 normal gravidas were enrolled. All patients with postpartum hypoxia underwent 24 h vital sign monitoring and relevant examinations, including hematological tests, chest computed tomography (CT) scans, or CT pulmonary angiography, to determine the cause of hypoxia and received appropriate treatments. All patients were followed up for 1 month.

Results

Compared with normal gravidas, the patients with postpartum hypoxia had a higher occurrence rate of complications, including gestational hypertension (26.09% vs 8.00%), eclampsia (20.65% vs 4.00%), and a lower level of albumin (29.09 ± 0.57 vs 32.74 ± 0.94), thus tended to have longer hospitalization days (7.98 ± 0.40 vs 4.90 ± 0.16), with all P < 0.05. In all 92 cases, the most common cause of postpartum hypoxia was partial atelectasis with pleural effusion (65/92), followed by pulmonary edema (18/92), pneumonia (9/92), pulmonary embolism (6/92), and asthma (4/92). Among the five groups, patients with pneumonia had the longest hospital stay, whereas most patients with partial atelectasis accompanied by pleural effusion were asymptomatic. From the 1-month follow-up, all patients had a favorable prognosis with no apparent symptoms. Among those who underwent re-examination (27/92), no apparent imaging abnormalities were detected.

Conclusion

Postpartum hypoxia, which occurs more commonly in patients with gestational hypertension, is often caused by partial atelectasis with pleural effusion or pulmonary edema. The patient's prognosis was generally satisfactory after treatment.

Miquelianin inhibits IAV infection via the MAPK signaling pathway both in vitro and in vivo

Background

Influenza is an acute respiratory infectious disease primarily transmitted through airborne droplets. The prevalence and spread of influenza viruses have significant impacts on global economic development and public health. Current prevention and control strategies for influenza virus infections mainly rely on vaccines and antiviral drugs. However, vaccine efficacy is limited by the antigenic drift and mutation characteristics of influenza viruses, while antiviral drug resistance is increasingly prevalent. Therefore, there is an urgent need for the development of novel antiviral agents. Flavonoids, widely distributed in plants, possess various potent biological properties, including antioxidant, anti-inflammatory, antibacterial, and anticancer activities, which contribute to the management and prevention of numerous diseases. This study aims to investigate the in vitro and in vivo anti-influenza A virus activity of quercetin, taxifolin, and miquelianin, as well as their underlying.

Methods

In vitro infection model (MDCK cells) and mouse lethal infection model of Infuenza A virus were used to evaluate the antiviral activity of quercetin, taxifolin and miquelianin. Subsequently, we applied network pharmacology to elucidate the mechanism of action and validate the findings for miquelianin.

Results

Miquelianin effectively inhibits the replication of H1N1-UI182 both in vitro and in vivo and provides protection against lethal H1N1-UI182 infection in mice. Compared to virus-infected controls, miquelianin reduces lung injury. Furthermore, by inhibiting the MAPK signaling pathway, miquelianin prevents the overproduction of cytokines, such as IL-6 and IL-1β, induced by viral infection, thereby alleviating inflammatory responses.

Conclusion

Miquelianin is a monomer extracted from traditional Chinese medicine, exhibiting inhibitory effects on H1N1-UI182 replication and lung injury mitigation.

A conjoint analysis of renal structure and omics characteristics reveal new insight to yak high-altitude hypoxia adaptation

BACKGROUND

Yaks have unique adaptive mechanisms to the hypoxic environment, in which the kidney plays an important role. The aim of this study was to explore the histological changes of yak kidney at different altitudes and the metabolites and genes associated with adaptation to the hypoxic environment.

METHODS

We analyzed the tissue structure and transcriptomic metabolomic data of yak kidney tissue at two altitudes, 2600 and 4400 m. We compared and identified the morphological adaptations of the kidney and the metabolites and genes associated with hypoxia adaptation in yaks. Changes in renal morphological adaptations, differential metabolites and genes were compared and identified, combining the two in a joint analysis.

RESULTS

High-altitude yak kidneys showed significant adaptive changes: increased mitochondria, increased glomerular thylakoid area, and decreased localized ribosomes. Transcriptomics and metabolomics identified 69 DAMs (Differential metabolites) and 594 DEGs (differential genes). Functional enrichment analysis showed that the DAMs were associated with protein digestion and absorption, ABC transporter, and MTOR signaling pathway; the DEGs were significantly enriched in Cholesterol metabolism and P53 signaling pathway. The joint analysis indicated that metabolites such as lysine and arginine, as well as key genes such as ABCB5 and COL1A2, were particularly affected under hypoxic conditions, whereas changes in mitochondria in the tissue structure may be related to the expression of MFN1 and OPA1, and changes in glomerular thylakoid membranes are related to VEGFA and TGFB3.

CONCLUSION

The kidney regulates metabolites and gene expression related to hormone synthesis, protein metabolism, and angiogenesis by adjusting the mitochondrial and glomerular thylakoid membrane structure to support the survival of yaks in high-altitude environments.

Circadian Clock and Hypoxia

The timing of life on Earth is remarkable: between individuals of the same species, a highly similar temporal pattern is observed, with shared periods of activity and inactivity each day. At the individual level, this means that over the course of a single day, a person alternates between two states. They are either upright, active, and communicative or they lie down in a state of (un)consciousness called sleep where even the characteristic of neuronal signals in the brain shows distinctive properties. The circadian clock governs both of these time stamps-activity and (apparent) inactivity-making them come and go consistently at the same approximate time each day. This behavior thus represents the meeting of two pervasive systems: the circadian clock and metabolism. In this article, we will describe what is known about how the circadian clock anticipates daily changes in oxygen usage, how circadian clock regulation may relate to normal physiology, and to hypoxia and ischemia that can result from pathologies such as myocardial infarction and stroke.