Chronic intermittent hypoxia and hypertension: A review of systemic inflammation and Chinese Medicine

Phytochemistry and Biological Profile of the Chinese Endemic Herb Genus Notopterygium

Notopterygium, a plant genus belonging to the Apiaceae family, is utilized in traditional Chinese medicine for its medicinal properties. Specifically, the roots and rhizomes of these plants are employed in phytotherapy to alleviate inflammatory conditions and headaches. This review provides a concise overview of the existing information regarding the botanical description, phytochemistry, pharmacology, and molecular mechanisms of the two Notopterygium species: Notopterygium incisum and N. franchetii. More than 500 distinct compounds have been derived from these plants, with the root being the primary source. These components include volatile oils, coumarins, enynes, sesquiterpenes, organic acids and esters, flavonoids, and various other compounds. Research suggests that Notopterygium incisum and N. franchetii exhibit a diverse array of pharmacological effects, encompassing antipyretic, analgesic, anti-inflammatory, antiarrhythmic, anticoagulant, antibacterial, antioxidant, and anticancer properties on various organs such as the brain, heart, digestive system, and respiratory system. Building activity screening models based on the pharmacological effects of Notopterygium species, as well as discovering and studying the pharmacological mechanisms of novel active ingredients, will constitute the primary development focus of Notopterygium medicinal research in the future.

Active metabolites and potential mechanisms of Notopterygium incisum against obstructive sleep apnea Syndrome (OSAS): network analysis and experimental assessment

Background: Notopterygium incisum K.C. Ting ex H.T. Chang, a synonym of Hansenia weberbaueriana (Fedde ex H. Wolff) Pimenov & Kljuykov, is an anti-inflammatory medicinal plant. Although abrnotopterol has been reported to be its primary active metabolite, the other metabolites and their mechanisms of action remain unclear. This study aims to investigate the potential mechanisms by which its active metabolites treat Obstructive Sleep Apnea Syndrome (OSAS) through network analysis and experimental assessment. Methods: The metabolites and potential targets of Notopterygium incisum were extracted from public databases. We searched for OSAS-related genes in the Genecards, OMIM, PharmGkb, TTD, and DrugBank databases. Cytoscape 3.9.0 was used to construct the drug-target-disease network and screen for hub genes. Human bronchial epithelial (HBE) cells were cultivated in normoxia and chronic intermittent hypoxia (CIH) medium for 24 h. Interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and prostaglandin E2 (PGE2) were quantified using enzyme-linked immunosorbent assay (ELISA). Prostaglandin-endoperoxide synthase 2(PTGS2) mRNA was detected using RT-qPCR, while PTGS2 and nuclear factor-kappa B (NF-κB) proteins were identified using Western blot analysis. Co-Immunoprecipitation (CoIP) and Western blotting were utilized to evaluate the ubiquitination of PTGS2 in HBE cells. Results: Pterostilbene and notopterol, isolated from Notopterygium incisum, had potential therapeutic effects on OSAS. The PTGS2 and estrogen receptor alpha (ESR1) hub genes were associated with OSAS. The pathway enrichment analysis focuses on the NF-κB, apoptosis, and HIF-1A pathways. In response to CIH, pterostilbene and notopterol decreased IL-6, TNF-α, and PGE2 levels. The NF-κB pathway was activated by an increase in PTGS2 levels. Pterostilbene promoted proteasome-mediated ubiquitination of PTGS2 protein and reduced PTGS2 levels, inhibiting the NF-κB pathway. Conclusion: This study reveals the active metabolites of Notopterygium incisum and hub genes involved in treating OSAS, which provide a basis for the follow-up development and exploitation of the botanical drug.

Traditional herbal medicine and nanomedicine: Converging disciplines to improve therapeutic efficacy and human health

Traditional herbal medicine (THM), an ancient science, is a gift from nature. For thousands of years, it has helped humans fight diseases and protect life, health, and reproduction. Nanomedicine, a newer discipline has evolved from exploitation of the unique nanoscale morphology and is widely used in diagnosis, imaging, drug delivery, and other biomedical fields. Although THM and nanomedicine differ greatly in time span and discipline dimensions, they are closely related and are even evolving toward integration and convergence. This review begins with the history and latest research progress of THM and nanomedicine, expounding their respective developmental trajectory. It then discusses the overlapping connectivity and relevance of the two fields, including nanoaggregates generated in herbal medicine decoctions, the application of nanotechnology in the delivery and treatment of natural active ingredients, and the influence of physiological regulatory capability of THM on the in vivo fate of nanoparticles. Finally, future development trends, challenges, and research directions are discussed.

The combination of intermittent electrical stimulation with acute intermittent hypoxia strengthens genioglossus muscle discharge in chronic intermittent hypoxia-pretreated rats

OBJECTIVE

Exploring whether the genioglossus discharge in chronic intermittent hypoxia(CIH) - pretreated rats could be enhanced by intermittent electrical stimulation combined with acute intermittent hypoxia(AIH).

METHODS

Rats were pretreated with CIH for 4 weeks and then were randomly divided into 6 groups: time control, intermittent electric stimulation, AIH, intermittent electric stimulation + AIH, continuous electric stimulation and continuous hypoxia exposure. The genioglossus discharges were recorded and compared before and after stimulation. Normoxic-treated rats were grouped and treated with the same stimulation protocols.

RESULTS

Intermittent electrical stimulation or AIH temporarily increased the activity of the genioglossus discharge, in which the degree of the increase was significantly higher in CIH-pretreated rats than in normoxic rats.After intermittent electrical stimulation, AIH evoked a sustained elevation of genioglossus discharge activities in CIH-pretreated rats, in which the degree of the increase was significantly higher than in rats induced by a single intermittent electric stimulation.

CONCLUSION

Intermittent electrical stimulation combined with AIH strengthens the genioglossus plasticity in CIH-pretreated rats.

miR-126a-3p targets HIF-1α and alleviates obstructive sleep apnea syndrome with hypertension

The obstructive sleep apnea syndrome (OSAS) is a common sleep-related breathing disorder and an important cause of refractory hypertension. MicroRNAs (miRNAs) are involved in the development of hypertension, but their role in OSAS with hypertension (OSAS-hypertension) has been little studied. Evidence indicates that miR-126a-3p expression is lower in patients with OSAS-hypertension compared with the patients with OSAS alone. However, its role in the pathogenesis of OSAS-hypertension remains unclear. Therefore, this study aims to investigate the role of miR-126a-3p in OSAS-hypertension and to determine whether HIF-1α is involved in this process. Sprague Dawley rats were exposed to chronic intermittent hypoxia (CIH) for 8 weeks to induce OSAS-hypertension. Rat aortic smooth muscle cells (A7r5) were cultured under hypoxia as an in vitro model. Our results showed that rats exposed to 8 week CIH exhibited decreased miR-126a-3p and increased HIF-1α expression. Furthermore, administration of recombinant adeno-associated virus expressing miR-126a-3p (rAAV-miR-126a) counteracted the CIH-induced systolic blood pressure upregulation, oxidase stress, inflammation, and heart and abdominal aorta vascular remodeling. Moreover, the mechanism was associated with its targeted suppression of HIF-1α. These findings suggest that miR-126a-3p might be a novel potential therapeutic target for the treatment of OSAS-hypertension.

Cashew (Anacardium occidentale L.) Nuts Counteract Oxidative Stress and Inflammation in an Acute Experimental Model of Carrageenan-Induced Paw Edema

Background: Anacardium occidentale L. is a medicinal plant with powerful anti-oxidative and anti-inflammatory properties. Acute inflammatory events cause tissue alterations, decrease of anti-oxidative endogenous enzymes such as superoxide dismutase, catalase and glutathione, neutrophils infiltration, increase in the activities of myeloperoxidase, malondialdehyde, and pro-inflammatory release. Methods: Paw edema was induced by subplantar injection of carrageenan into the right hind paw in rats, but 30 min before a group of animals were orally treated with 100 mg/kg of cashew nuts to evaluate the anti-inflammatory and anti-oxidative response. Results: In the present work, we found that (1) cashew nuts reduced the development of carrageenan-induced paw edema limiting the formation of edema and pain; (2) cashew nuts ameliorated the diminutions of the anti-oxidative enzymes caused by carrageenan injection; (3) cashew nuts decreased myeloperoxidase malondialdehyde activity induced by carrageenan; and (4) cashew nuts acted by blocking pro-inflammatory cytokines response and nitrate/nitrite formation stimulated by carrageenan injection. Conclusions: The mechanisms of anti-inflammatory and analgesic effects exerted by cashew nuts were relevant to oxygen free radical scavenging, anti-lipid peroxidation, and inhibition of the formation of inflammatory cytokines.

TLR4 mediates inflammation and hepatic fibrosis induced by chronic intermittent hypoxia in rats

Obstructive sleep apnea syndrome (OSAS) is a common and complex disorder that is associated with liver injury. Moreover, previous studies have revealed that chronic intermittent hypoxia (CIH) is associated with the development of non-alcoholic fatty liver disease and hepatic fibrosis. However, the underlying molecular mechanisms remain largely unknown. The present study aimed to investigate whether chronic intermittent hypoxia induced hepatic fibrosis, in addition to determining its underlying mechanisms, in CIH model rats using immunohistochemistry, western blotting and reverse transcription-quantitative PCR. The present results suggested that CIH caused hepatic fibrosis and increased the expression levels of interleukin (IL)-1β, IL-8, monocyte chemotactic-1, tumor necrosis factor-α, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in the liver; these conditions could be reversed by Toll-like receptor 4 (TLR4) short hairpin RNA lentivirus treatment. Moreover, immunohistochemistry and western blotting results indicated that TLR4 and NF-κB expression levels were significantly increased in the CIH and CIH-TLR4 empty vector lentivirus group. However, protein expression levels of TLR4, NF-κB, inhibitor of NF-κB and phosphorylated-mitogen-activated protein kinase (MAPK)-1 in the hypoxia/reoxygenation group were significantly higher compared with the control group (P<0.05), and these results were reversed by the MAPK inhibitor U0126 in vitro. Collectively, the present preliminary results suggested that inflammation and the TLR4/NF-κB/MAPK signaling pathway may be involved in CIH-induced liver fibrosis.

A review of the association between oral bacterial flora and obstructive sleep apnea-hypopnea syndrome comorbid with cardiovascular disease

PURPOSE

Obstructive sleep apnea-hypopnea syndrome (OSAHS), a common sleep disorder, has been shown to be an independent risk factor for cardiovascular disease (CVD). Recent studies have focused on the important roles of microorganisms in human health; for example, microorganisms are reportedly associated with obesity, metabolic disorders, and CVD. The number of oral bacteria in patients with OSAHS is considerably higher than that in healthy individuals, and infection with oral bacterial pathogens is associated with the development of CVD. However, whether changes in the oral microbiota mediate the development of OSAHS and CVD remains unknown.

METHODS

Therefore, we attempted to review the association between changes in oral microbiota in patients with OSAHS and the development of CVD.

RESULTS

Oral microbiota possibly acts via multiple pathways including direct invasion, platelet aggregation, immune response, inflammatory response, and oxidative stress response, leading to the development of CVD in patients with OSAHS. In particular, the strains Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia have demonstrated profound effects. OSAHS leads to changes in the oral bacterial flora and thus may facilitate the occurrence and development of CVD.

CONCLUSION

We propose that the underlying mechanism of CVDs resulting from oral microbiota in patients with OSAHS should be elucidated in further studies.

Tumor necrosis factor receptor-associated protein 1 regulates hypoxia-induced apoptosis through a mitochondria-dependent pathway mediated by cytochrome c oxidase subunit II

Background

Tumor necrosis factor receptor-associated protein 1 (TRAP1) plays a protective effect in hypoxic cardiomyocytes, but the precise mechanisms are not well clarified. The study is aimed to identify the mechanism of TRAP1 on hypoxic damage in cardiomyocytes.

Methods

In this study, the effects of TRAP1 and cytochrome c oxidase subunit II (COXII) on apoptosis in hypoxia-induced cardiomyocytes were explored using overexpression and knockdown methods separately.

Results

Hypoxia induced cardiomyocyte apoptosis, and TRAP1 overexpression notably inhibited apoptosis induced by hypoxia. Conversely, TRAP1 silencing promoted apoptosis in hypoxic cardiomyocytes. Further investigation revealed that the proapoptotic effects caused by the silencing of TRAP1 were prevented by COXII overexpression, whereas COXII knockdown reduced the antiapoptotic function induced by TRAP1 overexpression. Additionally, changes in the release of cytochrome c from mitochondria into the cytosol and the caspase-3 activity in the cytoplasm, as well as reactive oxygen species production, were found to be correlated with the changes in apoptosis.

Conclusions

The current study uncovered that TRAP1 regulates hypoxia-induced cardiomyocyte apoptosis through a mitochondria-dependent apoptotic pathway mediated by COXII, in which reactive oxygen species presents as an important component.

Electronic supplementary material

The online version of this article (10.1186/s41038-019-0154-3) contains supplementary material, which is available to authorized users.

Analysis of oral microbiota in patients with obstructive sleep apnea-associated hypertension

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is an independent risk factor for hypertension (HTN). The oral microbiota plays a pathophysiological role in cardiovascular diseases; however, there are few reports directly investigating and identifying the organisms involved in OSAHS-related HTN. Therefore, this study aimed to identify those organisms. We obtained 139 oral samples and determined the microbiome composition using pyrosequencing and bioinformatic analyses of the 16S rRNA. We examined the fasting levels of cytokines and homocysteine in all participants and analyzed the correlations between the oral microbiota and homocysteine levels. We determined the molecular mechanism underlying HTN by investigating the genetic composition of the strains in the blood. We detected higher relative abundances of Porphyromonas and Aggregatibacter and elevated proinflammatory cytokines in patients with OSAHS of varying severity compared with individuals without OSAHS; however, the two organisms were not measured in the blood samples from all participants. High levels of specific Porphyromonas bacteria were detected in patients with OSAHS with and without HTN, whereas the relative abundance of Aggregatibacter was negatively correlated with the homocysteine level. The receiver operating characteristic curve analysis of controls and patients with OSAHS resulted in area under the curve values of 0.759 and 0.641 for patients with OSAHS with or without HTN, respectively. We found that the predictive function of oral microbiota was different in patients with OSAHS with and without HTN. However, there was no direct invasion by the two organisms causing endothelial cell injury, leading to speculation regarding the other mechanisms that may lead to HTN. Elucidating the differences in the oral microbiome will help us understand the pathogenesis of OSAHS-related HTN.

Evaluation of Analgesic and Anti-Inflammatory Activities of Water Extract of Galla Chinensis In Vivo Models

AIM

Pain and inflammation are associated with many diseases in humans and animals. Galla Chinensis, a traditional Chinese medicine, has a variety of pharmacological properties. The purpose of this study was to evaluate analgesic and anti-inflammatory activities of Galla Chinensis through different animal models.

METHOD

The analgesic activities were evaluated by hot-plate and writhing tests. The anti-inflammatory effects were assessed by ear edema, capillary permeability, and paw edema tests. The contents of cytokines (NO, iNOS, PGE2, and IL-10) in serum of rats in paw edema test were inspected by ELISA assays.

RESULTS

In the hot-plate test, Galla Chinensis could significantly extend pain threshold when compared to control group. The inhibitory rates of writhes ranged from 36.62% to 68.57% in Galla Chinensis-treated mice. Treatment with Galla Chinensis (1 and 0.5 g/kg) could significantly inhibit ear edema (47.45 and 36.91%, resp.; P < 0.01). Galla Chinensis (1 g/kg) had significant (P < 0.05) anti-inflammatory activity in capillary permeability test (29.04%). In carrageenan-induced edema test, the inhibitory rates were 43.71% and 44.07% (P < 0.01) at 1 h and 2 h after administration of Galla Chinensis (1 g/kg), respectively, and the levels of proinflammatory cytokines were significantly reduced.

CONCLUSION

These results suggest that Galla Chinensis has analgesic and anti-inflammatory effects, which may be a candidate drug for the treatment of inflammation and pain.

Changes in inflammatory mediators as a result of intermittent hypoxia in obstructive sleep apnea syndrome

BACKGROUND

Inflammation plays an important role in obstructive sleep apnea syndrome (OSAS). The objective of this study was to investigate the relationship of serum C-reactive protein (CRP), pentraxin-3 (PTX-3), procalcitonin (ProCT), interleukin-33 (IL-33) and its soluble receptor ST2 (sST2) with the syndrome severity and to show theirs importance as biomarkers.

METHODS

This study comprises a total of 84 identical (sex and age wise) cases. Full-night polysomnography was performed in each patient. OSAS diagnosis and severity index being based on the widely used criterion known as Apnea Hypopnea Index(AHI). Subgroups were as follows: 24(AHI < 5) controls, 28 mild-moderate OSAS(AHI 5-30) and 32 severe OSAS(AHI > 30).

RESULTS

PTX-3, IL-33 and sST2 receptors were significantly higher in OSAS groups than the control group (P < .001). However, both CRP and ProCT levels were similar in all subjects. There was a positive correlation between PTX-3 and BMI (r = 0.446; P < .01), ODI (r = 0.555; P < .01), IL-33 (r = 0.348; P = .001) and sST2 (r = 326; P = .002), while there was a negative correlation with minimum SaO₂ (r = -0.672; P < .01) in patient group. PTX-3 as a predictor of OSAS showed highest specificity (%91.7) and sensitivity (%91.7) (P < .001).

CONCLUSIONS

PTX-3 can be a new indicator reflecting the inflammatory state in patients with OSAS. Since patients with OSAS could have more hypoxic state during sleep, we found higher PTX-3 level in those patients and a negative correlation between PTX-3 and minimum SaO₂ , which could explain that PTX-3 levels can increase with the severity of disease. Our results suggest that PTX-3 as an inflammatory biomarker may play a crucial role as an indicator of syndrome severity in OSAS.

Obstructive sleep apnea: Influence of hypertension on adiponectin, inflammatory markers and dyslipidemia

Obstructive sleep apnea (OSA) is a common but often unrecognized condition with potentially serious complications. The aim of this study was to explore the possible mechanisms linking hypertension (HT), a common cardiovascular disease (CVD), with obstructive sleep apnea (OSA) by investigating the levels of morning and evening serum adiponectin, inflammatory markers (TNF-α, IL-6), and lipid profiles in OSA patients with and without HT. Four groups were enrolled in this case-control analytic study: control, OSA, OSA+HT, and HT groups, each of which included 22 subjects. The results revealed low morning and evening serum adiponectin levels in patients with OSA and OSA+HT compared with their control and HT counterparts. Serum adiponectin levels declined progressively with increasing severity of OSA. Also, morning adiponectin levels were significantly decreased at the same time that a loss of the normal diurnal rhythm was observed in the OSA and OSA+HT groups. Both TNF-α and IL-6 levels were significantly increased in the OSA and OSA+HT groups compared with levels in the control and HT groups. Altered lipid profiles was noticed in the same groups. These findings were more pronounced in the OSA+HT than in the OSA group. In conclusion, the biochemical findings of this study demonstrate predominantly low adiponectin levels, increased levels of inflammatory markers, and atherogenic lipid profiles in OSA patients with HT compared with those of the other patients studied. This highlights the possible contributing role of these factors to the pathogenesis of HT as a common cardiovascular complication in OSA patients.

WITHDRAWN: Detection and analysis of apoptosis- and autophagy-related miRNAs of vascular endothelial cells in a mouse chronic intermittent hypoxia model

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Roles and Mechanisms of Obstructive Sleep Apnea-Hypopnea Syndrome and Chronic Intermittent Hypoxia in Atherosclerosis: Evidence and Prospective

The morbidity and mortality of obstructive sleep apnea-hypopnea syndrome (OSAHS) are regarded as consequences of its adverse effects on the cardiovascular system. Chronic intermittent hypoxia (CIH) induced by OSAHS can result in vascular endothelial injury, thus promoting development of atherosclerosis (AS). Studies have shown that CIH is an independent risk factor for the occurrence and development of AS, but the underlying mechanism remains unclear. Here, we review clinical and fundamental studies reported during the last 10 years on the occurrence and development of AS mediated by CIH, focusing on inflammation, oxidative stress, insulin resistance, cell apoptosis, vascular endothelial injury, platelet activation, and neuroendocrine disorders. This review will offer current evidence and perspective to researchers for the development of effective intervention strategies for OSAHS-related cardiocerebrovascular diseases.