Advances in Pharmacological Actions and Mechanisms of Flavonoids from Traditional Chinese Medicine in Treating Chronic Obstructive Pulmonary Disease

Baicalin Relieves Airway Inflammation in COPD by Inhibiting miR-125a

To investigate the effects of Baicalin on the apoptosis of human bronchial epithelial cells (16HBE) induced by cigarette smoke extract (CSE) and the release of inflammatory factors, and to clarify its possible mechanism. CSE was used to treat 16HBE cells and construct COPD cell model. The activity of 16HBE cells was detected by CCK-8 and BrdU. Real-time fluorescence quantitative PCR (RT-QPCR) was used to detect the expression level of miR-125a in each group of 16HBE cells. At the same time, the levels of 16HBE inflammatory cytokines IL-1β, IL-8, IL-6, and TNF-α were detected. The apoptosis rate of 16HBE cells in each group was detected by TUNEL. Compared with the control group, the proliferation of 16HBE cells in CSE group was decreased. Baicalin reversed the effect of 2% CSE on the proliferation of 16HBE cells. Baicalin also reversed the effect of 2% CSE on apoptosis and inflammatory factors in 16HBE cells. miR-125a is highly expressed in COPD, and Baicalin can inhibit the expression of miR-125a. Silencing miR-125a reduces apoptosis and inflammatory response of 16HBE cells in COPD. miR-125a reversed the effects of Baicalin on apoptosis and inflammation of 16HBE cells. Baicalin can reduce CSE-induced apoptosis of human bronchial epithelial cells and release of inflammatory factors, and its mechanism may be related to the inhibition of miR-125a.

Efficacy of acupuncture-related therapy in the treatment of primary dysmenorrhea: A network meta-analysis of randomized controlled trials

Objectives

In order to compare and rank the most effective acupuncture therapy for primary dysmenorrhea and provide evidence-based medical support for clinical treatment of this disease.

Methods

A comprehensive search was conducted on China National Knowledge Infrastructure (CNKI), Wanfang Database, Information Chinese Journal Service Platform (VIP), China Biomedical Literature Service System (SinoMed), PubMed, Web of Science, Embase, and Cochrane Library databases from their inception to May 1, 2023. The Cochrane Collaboration Risk of Bias Tool was used to evaluate bias risk, and the GeMTC package of Stata 15.1 software and R 4.3.1 software was used to perform network Meta-analysis.

Results

70 studies were included, including 5772 patients with primary dysmenorrhea, involving 25 kinds of acupuncture techniques commonly used in clinic. The quality of the included literature was low, most of them did not mention the registration information of clinical trial centers, and the specific sample size estimation method was unclear. Some literature did not explain the specific random method, distribution concealment and blindness, so there was a certain publication bias and small sample effect. Results showed that for improving the clinical effective rate, the top three treatments were salt-separated moxibustion, massotherapy + acupoint patching, acupuncture + heat-sensitive moxibustion. In terms of reducing the visual analogue scale(VAS), the top three treatments were massotherapy + acupoint patching, acupuncture + acupoint patching and warm acupuncture. In terms of alleviating cox menstrual symptom scale (CMSS), the top three treatments were acupuncture + acupoint patching, acupoint patching and point embedding. In relieving TCM symptom score, the top three treatments were acupoint patching + heat-sensitive moxibustion, acupoint patching and moxibustion.

Conclusion

Different acupuncture therapies have more advantages than oral analgesics in improving the clinical effective rate, reducing VAS score, reducing CMSS score, and alleviating TCM symptom score. Among them, massage therapy + acupoint patching, acupuncture + acupoint patching and acupoint patching may be the best solutions for the treatment of primary dysmenorrhea. However, more large-sample, multi-center and high-quality randomized controlled trials are needed to demonstrate.

Association of dietary flavonoid intakes with prevalence of chronic respiratory diseases in adults

BACKGROUND AND AIMS

Flavonoids are a class of secondary plant metabolites that have been shown to have multiple health benefits, including antioxidant and anti-inflammatory. This study was to explore the association between dietary flavonoid consumption and the prevalence of chronic respiratory diseases (CRDs) in adults.

METHODS AND RESULTS

The six main types of flavonoids, including isoflavones, anthocyanidins, flavan-3-ols, flavanones, flavones, and flavonols, were obtained from the National Health and Nutrition Examination Survey (NHANES) 2007-2010 and 2017-2018 by the two 24-h recall interviews. The prevalence of CRDs, including asthma, emphysema, and chronic bronchitis, was determined through a self-administered questionnaire. The analysis included 15,753 participants aged 18 years or older who had completed a diet history interview. After adjustment for potential confounders, the inverse link was found with total flavonoids, anthocyanidins, flavanones, and flavones, with an OR (95%CI) of 0.86 (0.75-0.98), 0.84 (0.72-0.97), 0.80(0.69-0.92), and 0.85(0.73-0.98) for the highest group compared to the lowest group. WQS regression revealed that the mixture of flavonoids was negatively linked with the prevalence of CRDs (OR = 0.88 [0.82-0.95], P < 0.01), and the largest effect was mainly from flavanones (weight = 0.41). In addition, we found that flavonoid intake was negatively linked with inflammatory markers, and systemic inflammation significantly mediated the associations of flavonoids with CRDs, with a mediation rate of 12.64% for CRP (P < 0.01).

CONCLUSION

Higher flavonoid intake was related with a lower prevalence of CRDs in adults, and this relationship may be mediated through systemic inflammation.

Exploration of the Mechanism of Shengxian Decoction Against Chronic Obstructive Pulmonary Disease Based on Network Pharmacology and Experimental Verification

Shengxian decoction (SXT) is clinically used in chronic obstructive pulmonary disease (COPD) treatment. This study aimed to explore the mechanism and target genes of SXT acting on COPD. Differentially expressed genes (DEGs) between COPD and controls were identified and then performed enrichment analysis. The effective active compounds and corresponding target genes were obtained from the traditional Chinese medicine systems pharmacology database. We also compiled COPD related genes from the GeneCards database. Through the protein-protein interaction (PPI) network and least absolute shrinkage and selection operator (LASSO) regression was performed to identify key genes. Molecular docking was used for docking of key genes and compounds. The expression of key genes was detected by quantitative real-time PCR in COPD patients and bronchial epithelial cells stimulated with cigarette stroke extract (CSE). We identified 1,458 intersected DEGs from GSE47460 and GSE57148 datasets. Compared with intersected DEGs, we obtained 33 SXT target COPD-related genes. PI3K-Akt signaling pathway, MAPK signaling pathway, and focal adhesion were enriched by these 33 genes, as well as intersected DEGs. According to LASSO regression, there were 12 genes considered as signature genes. Then we constructed active compounds and corresponding six target genes. Finally, HIF1A and IL1B were selected as key genes by combining PPI network. HIF1A and IL1B were all upregulated expression in COPD and CSE stimulated cells and recovered in SXT treated CSE stimulated cells. This study provides a scientific basis for the identification of active compounds and target genes of SXT in the treatment of COPD.

Effects of Ipratropium Bromide Combined with Traditional Chinese Medicine Intervention on the Pulmonary Function and Psychological Status of Patients with Chronic Obstructive Pulmonary Disease

Recently, most scholars have advocated multidisciplinary comprehensive intervention measures for chronic obstructive pulmonary disease (COPD) to improve lung function, relieve symptoms of dyspnea, and improve quality of life. Traditional Chinese medicine (TCM) has rich experience in the treatment of various respiratory system diseases and the rehabilitation of their syndrome differentiation. In this study, total 68 patients with COPD from November 2019 to November 2021 in the hospitals were divided into the control group, ipratropium bromide (IB)-treated group, and IB + TCM-treated group for clinical efficacy observation and to explore the effect of IB combined with TCM on the pulmonary function and psychological status of COPD patients. Patients in the control group were subjected to routine oxygen inhalation, cough and expectorant, and antiviral treatments, while the patients in the IB-treated group were treated with IB and those received in the control group. Patients in the IB + TCM-treated group were treated with IB and TCM intervention. All patients were treated for a month. The results showed that after different interventions, the levels of FEV1, FEV1% pred, FVC, and PEF (P < 0.05) were significantly increased in all the groups, while levels of TNF-α, IL-6, IL-8, and CRP in serum as well as Hamilton Anxiety Scale and Hamilton Depression scores were significantly decreased. Compared with the control group and IB-treated group, the IB + TCM-treated group presented the greatest changes on all abovementioned indicators and the lowest total incidence of adverse reactions, indicating the biggest improvement of IB + TCM on the symptoms of COPD patients. Therefore, the combination of IB and TCM intervention effectively improved the pulmonary function and psychological status of COPD patients and could be used as an important adjunct for COPD treatment.

The therapeutic potential of quercetin for cigarette smoking-induced chronic obstructive pulmonary disease: a narrative review

Quercetin is a flavonoid with antioxidant and anti-inflammatory properties. Quercetin has potentially beneficial therapeutic effects for several diseases, including cigarette smoking-induced chronic obstructive pulmonary disease (CS-COPD). Many studies have shown that quercetin's antioxidant and anti-inflammatory properties have positive therapeutic potential for CS-COPD. In addition, quercetin's immunomodulatory, anti-cellular senescence, mitochondrial autophagy-modulating, and gut microbiota-modulating effects may also have therapeutic value for CS-COPD. However, there appears to be no review of the possible mechanisms of quercetin for treating CS-COPD. Moreover, the combination of quercetin with common therapeutic drugs for CS-COPD needs further refinement. Therefore, in this article, after introducing the definition and metabolism of quercetin, and its safety, we comprehensively presented the pathogenesis of CS-COPD related to oxidative stress, inflammation, immunity, cellular senescence, mitochondrial autophagy, and gut microbiota. We then reviewed quercetin's anti-CS-COPD effects, performed by influencing these mechanisms. Finally, we explored the possibility of using quercetin with commonly used drugs for treating CS-COPD, providing a basis for future screening of excellent drug combinations for treating CS-COPD. This review has provided meaningful information on quercetin's mechanisms and clinical use in treating CS-COPD.

Gou Qi Zi inhibits proliferation and induces apoptosis through the PI3K/AKT1 signaling pathway in non-small cell lung cancer

Background

Gou Qi Zi (Lycium barbarum) is a traditional herbal medicine with antioxidative effects. Although Gou Qi Zi has been used to prevent premature aging and in the treatment of non-small cell lung cancer (NSCLC), its mechanism of action in NSCLC remains unclear. The present study utilized network pharmacology to assess the potential mechanism of action of Gou Qi Zi in the treatment of NSCLC.

Methods

The TCMSP, TCMID, SwissTargetPrediction, DrugBank, DisGeNET, GeneCards, OMIM and TTD databases were searched for the active components of Gou Qi Zi and their potential therapeutic targets in NSCLC. Protein-protein interaction networks were identified and the interactions of target proteins were analyzed. Involved pathways were determined by GO enrichment and KEGG pathway analyses using the Metascape database, and molecular docking technology was used to study the interactions between active compounds and potential targets. These results were verified by cell counting kit-8 assays, BrdU labeling, flow cytometry, immunohistochemistry, western blotting, and qRT-PCR.

Results

Database searches identified 33 active components in Gou Qi Zi, 199 predicted biological targets and 113 NSCLC-related targets. A network of targets of traditional Chinese medicine compounds and potential targets of Gou Qi Zi in NSCLC was constructed. GO enrichment analysis showed that Gou Qi Zi targeting of NSCLC was mainly due to the effect of its associated lipopolysaccharide. KEGG pathway analysis showed that Gou Qi Zi acted mainly through the PI3K/AKT1 signaling pathway in the treatment of NSCLC. Molecular docking experiments showed that the bioactive compounds of Gou Qi Zi could bind to AKT1, C-MYC and TP53. These results were verified by experimental assays.

Conclusion

Gou Qi Zi induces apoptosis and inhibits proliferation of NSCLC in vitro and in vivo by inhibiting the PI3K/AKT1 signaling pathway.

Scutellaria barbata D. Don inhibits cervical cancer cell proliferation, migration, and invasion via miR-195-5p/LOXL2 axis

Background

Scutellaria barbata D. Don (SB) is a widely used herbal medicine in China, with various pharmacological effects such as anti-oxidation, anti-inflammation, and anti-cancer. This work is aimed to investigate the tumor-suppressive effect of SB in cervical cancer (CC) and to identify its underlying mechanisms.

Methods and materials

CC cell lines (HeLa and HT-3) were treated with different concentrations of SB chloroform extract (ECSB) (0, 0.2, 0.5 mg/ml). MiR-195-5p and LOXL2 mRNA expression in CC cell lines and tissue samples was detected by quantitative real-time polymerase chain reaction. Cell counting kit-8 experiment was utilized to examine cell viability; TUNEL assay and Transwell experiment was executed to examine cell apoptosis, migration, and invasion. Western blotting experiments were implemented to detect LOXL2 protein expression. Bioinformatics and dual-luciferase reporter gene experiment were executed to examine the binding relationship between miR-195-5p and LOXL2.

Results

ECSB repressed the viability, migration, and invasion of HeLa and HT-3 cells, and promoted cell apoptosis in a dose-dependent manner. MiR-195-5p was remarkably under-expressed in CC tissues and cells, and ECSB up-regulated miR-195-5p expression. MiR-195-5p inhibitors partially counteracted the suppressive effects of ECSB on the malignant phenotypes of HeLa and HT-3 cells. LOXL2 was a downstream target of miR-195-5p, and ECSB up-modulated LOXL2 expression by specifically repressing miR-195-5p.

Conclusion

SB restrains CC cell proliferation and metastasis and promotes cell apoptosis via miR-195-5p/LOXL2, which may be a potential therapeutic agent for CC treatment.

Chemical Structures and Pharmacological Properties of Typical Bioflavonoids in Polygonati Rhizoma (PGR)

Most medicines are coming with toxic and detrimental side effects. In addition, microbials are resisting the medicine. Therefore, alternative drugs with low toxic and side effects and low microbial resistance are needed. Plants offer good potential candidates due to a broad range of chemicals they contain. These chemicals have been studied, and research is still going on to probe chemical properties of plant chemicals. In China, traditional Chinese medicine is practised, whereby plant extracts are obtained, and then sold in packages for reasons like memory enhancement, cancer treatment, boosting immune system, and so on. Among the herbs cultivated in China is Polygonati rhizoma (PGR). This plant contains various bioflavonoids such as diosgenin, kaempferol, catechin, daidzein, and 3'-methoxydaidzein. In this review, we discussed the pharmacological effects of these chemicals, including luteolin antimicrobial activity in a manner that it circumvents antibiotic resistance; rutin antivenom property; kaempferol as an agent that mitigates neuropathic pain; genistein anticancer property; isorhamnetin's ability to alleviate chronic obstructive pulmonary diseases (COPD); proanthocyanidins' ability to deal with diabetic neuropathy and analgesic property of catechin.

Combined Tai Chi and cognitive interventions for older adults with or without cognitive impairment: A meta-analysis and systematic review

BACKGROUND AND PURPOSE

Evidence from the field of cognitive interventions indicates that nonpharmaceutical interventions seem more promising in enhancing cognition. The number of clinical trials that examine the cognitive benefits of combined physical exercise with cognitive intervention on older adults has recently increased. Tai Chi (TC) has been recommended as an effective and safe exercise for older adults aged 60 and over. However, there is a lack of conclusion about whether combined TC with cognitive interventions can show more benefits than a single intervention for older adults. Thus, this review aimed to evaluate the effects of combined TC and cognitive interventions on older adults.

METHODS

PubMed, Embase, PsycINFO, and Web of Science were searched for English peer-reviewed papers from inception until November 12, 2021. Data were extracted by two independent reviewers.

RESULTS

A total of 1524 records were generated and nine studies were included. The pooled results showed that combined TC and cognitive interventions showed significantly large gains on memory [standardised mean difference (SMD) = 0.87, 95% confidence interval (CI): (0.01, 1.74), P 0.05], moderate gains on cognition [SMD = 0.74, 95% CI:(0.19, 1.29), P 0.05], and small size effects on balance. No statistically significant difference was found in executive function, depression, risk of falls, or well-being.

CONCLUSION

Combined TC and cognitive interventions have positive effects on improving cognition and balance in older adults, but their superiority over the single intervention, as well as their additional effects on the physical and psychological function, are required further investigation.

Effect of Yifei-Huoxue Decoction Combined with Tiotropium on Inflammatory Cytokine Levels, Pulmonary Function, and Quality of Life in Patients with Chronic Obstructive Pulmonary Disease

Objective

The main objective is to investigate the effect of Yifei-Huoxue decoction combined with tiotropium on the inflammatory cytokine levels, pulmonary function, and quality of life in patients with chronic obstructive pulmonary disease (COPD).

Methods

Ninety-eight COPD patients who were treated in our hospital from January 2021 to January 2022 were selected as the research objects, and they were divided into reference group (routine treatment) and study group (Yifei-Huoxue decoction combined with tiotropium), with 49 cases in each group. The patients' clinical indexes were compared between the two groups, and the clinical efficacy in the two groups was analyzed.

Results

Compared with the reference group, the study group had remarkably lower inflammatory cytokine levels (including tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and interleukin-6 (IL-6)) after treatment (P > 0.05). In terms of the patients' pulmonary function indexes after treatment, the study group achieved lower forced vital capacity (FVC), forced expiratory volume in 1s (FEV1), and FEV1/FVC levels compared with the reference group (P < 0.05). Both groups had a lower erythrocyte sedimentation rate (ESR) after treatment compared with that before treatment. However, the intergroup difference in the ESRs after treatment was remarkable, and the study group had a much lower ESR compared with the reference group (P < 0.05). Compared with the reference group, the study group achieved much higher 36-item short form health survey (SF-36) scores in dimensions of general health, physical functioning, social functioning, and mental health after treatment (P < 0.05).

Conclusion

Yifei-Huoxue decoction combined with tiotropium not only enhances the COPD patients' pulmonary function but also decreases their inflammatory levels. Therefore, this treatment is conducive to promoting the COPD patients' recovery and exerts positive effect on improving their quality of life.

lncRNA GAS5 promotes pyroptosis in COPD by functioning as a ceRNA to regulate the miR‑223‑3p/NLRP3 axis

Chronic obstructive pulmonary disease (COPD) is characterized by irreversible and progressive airflow limitation and encompasses a spectrum of diseases, including chronic obstructive bronchitis and emphysema. Pyroptosis is a unique form of inflammatory cell death mediated by the activation of caspase-1 and inflammasomes. The long non-coding RNA (lncRNA) growth arrest-specific 5 (GAS5) is a well-documented tumor suppressor, which is associated with cell proliferation and death in various diseases. The aim of the present study was to evaluate whether lncRNA GAS5 is associated with the pyroptosis in COPD. To create a COPD cell model, MRC-5 cells were treated with 10 µg/ml lipopolysaccharide (LPS) for 48 h. Then the level of pro-caspase 1, caspase 1, IL-1β, IL-18, NLRP3 and cleaved gasdermin D (GSDMD) was examined by western blotting. GAS5 mRNA level was detected by qualitative PCR following LPS treatment in MRC-5 cells. Subsequently, IL-2, IL-6, IL-10 and TNF-α in MRC-5 cells was measured by ELISA. Then the proliferation ability of MRC-5 cells was detected by CCK-8. Cell death was detected by TUNEL assay. LDH release was measured using an LDH Cytotoxicity Assay kit. The Magna RIP kit was used to validate the interaction between GAS5 and miR-223-3p. The present study revealed that increased expression levels of caspase-1, IL-1β, IL-18 and cleaved GSDMD were observed in LPS-treated MRC-5 cells, indicating that pyroptosis is involved in COPD progression. Additionally, LPS induced the increase in GAS5 mRNA expression levels and the release of inflammatory factors (IL-2, IL-6, IL-10 and TNF-α), suggesting that GAS5 is implicated in pyroptosis in COPD. Furthermore, upregulation of GAS5 promoted cell death and inhibited proliferation in the MRC-5 cell line. Additionally, increased GAS5 expression significantly promoted the production of caspase-1, IL-1β, IL-18, cleaved GSDMD and NLR pyrin domain containing protein 3 (NLRP3). A dual-luciferase assay demonstrated that GAS5 could directly bind to microRNA-223-3p (miR-223-3p), and NLRP3 is a direct target of miR-223-3p. Furthermore, GAS5 reduced the expression levels of miR-223-3p, while it increased the expression levels of NLRP3. The present study concluded that lncRNA GAS5 promoted pyroptosis in COPD by targeting the miR-223-3p/NLRP3 axis, implying that GAS5 could be a potential target for COPD.

Isorhamnetin Alleviates Airway Inflammation by Regulating the Nrf2/Keap1 Pathway in a Mouse Model of COPD

Chronic obstructive pulmonary disease (COPD) is a severely disabling chronic lung disease characterized by persistent airway inflammation, which leads to limited expiratory airflow that deteriorates over time. Isorhamnetin (Iso) is one of the most important active components in the fruit of Hippophae rhamnoides L. and leaves of Ginkgo biloba L, which is widely used in many pulmonary disease studies because of its anti-inflammatory effects. Here, we investigated the pharmacological action of Iso in CS-induced airway inflammation and dissected the anti-inflammation mechanisms of Iso in COPD mice. A mouse model of COPD was established by exposure to cigarette smoke (CS) and intratracheal inhalation of lipopolysaccharide (LPS). Our results illustrated that Iso treatment significantly reduced leukocyte recruitment and excessive secretion of interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and regulated upon activation, normal T-cell expressed and secreted (RANTES) in BALF of CS-induced COPD mice in a dose-dependent manner. This improved airway collagen deposition and emphysema, and further alleviated the decline in lung functions and systemic symptoms of hypoxia and weight loss. Additionally, Iso treatment obviously improves the T lymphocyte dysregualtion in peripheral blood of COPD mice. Mechanistically, Iso may degrade Keap1 through ubiquitination of p62, thereby activating the nuclear factor erythroid 2-related factor (Nrf2) pathway to increase the expression of protective factors, such as heme oxygenase-1 (HO-1), superoxide dismutase (SOD) 1, and SOD2, in lungs of CS-exposed mice, which plays an anti-inflammatory role in COPD. In conclusion, our study indicates that Iso significantly alleviates the inflammatory response in CS-induced COPD mice mainly by affecting the Nrf2/Keap1 pathway. More importantly, Iso exhibited anti-inflammatory effects comparable with Dex in COPD and we did not observe discernible side effects of Iso. The high safety profile of Iso may make it a potential drug candidate for COPD.

Accumulation Pattern of Flavonoids during Fruit Development of Lonicera maackii Determined by Metabolomics

Lonicera maackii (Caprifoliaceae) is a large, upright shrub with fruits that contain many bioactive compounds. Flavonoids are common active substances in L. maackii. However, there is a dearth of information about the accumulation of these flavonoids and their possible medicinal value. We used targeted metabolomics analysis based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to analyze five developmental stages of L. maackii fruit. A total of 438 metabolites were identified in the five developmental stages, including 81 flavonoids and derivatives. The 81 flavonoids included 25 flavones and derivatives, 35 flavonols and derivatives, two isoflavones, three cyanidins and derivatives, eight procyanidins, and eight flavanones. In addition, we outlined the putative flavonoid biosynthesis pathway and screened their upstream metabolites. More importantly, we analyzed the accumulation patterns of several typical flavones and flavonols. The results reported here improved our understanding of the dynamic changes in flavonoids during fruit development and contributed to making full use of the medicinal value of L. maackii fruit.

Herbal Medicine Compared to Placebo for Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

Chronic obstructive pulmonary disease (COPD) is a respiratory disease characterized by irreversible airflow limitation. Many COPD patients use complementary and alternative modalities, including herbal medicines (HMs). This systematic review investigated the effectiveness and safety of HM in managing COPD symptoms compared to placebo. Nine electronic databases were searched to identify relevant randomized controlled trials (RCTs) up to February 12, 2021. The Cochrane risk of bias tool was used to assess the methodological qualities of the included studies. Primary outcomes were lung function parameters and exercise capacity. A meta-analysis was conducted to determine the effect size for homogeneous outcomes. Fourteen studies were included. There was low to very low quality evidence that HM significantly improved forced expiratory volume in 1  s (FEV1) (L), FEV1 (%) and 6-minute walk distance, as well as moderate quality evidence that HM significantly improved forced vital capacity (FVC) (L) compared to placebo. However, according to low quality evidence, there was no significant difference in FEV1/FVC (%) or vital capacity (L) between the groups. Low to moderate evidence suggests that HM has the potential to help improve some respiratory functions, COPD symptoms, and some aspects of quality of life in COPD patients compared to placebo. However, these findings are challenged by the poor methodological quality of the included studies, the heterogeneity of HMs used, and potential publication bias. Therefore, the findings could be significantly influenced by further larger, more rigorous RCTs on this topic. Moreover, it may also be recommended to develop standardized HMs focused on some individual herbs that are frequently used or expected to play an important role in patients with COPD, and to elucidate the underlying mechanisms.

Therapeutic Effects and Molecular Mechanisms of Bioactive Compounds Against Respiratory Diseases: Traditional Chinese Medicine Theory and High-Frequency Use

Respiratory diseases, especially the pandemic of respiratory infectious diseases and refractory chronic lung diseases, remain a key clinical issue and research hot spot due to their high prevalence rates and poor prognosis. In this review, we aimed to summarize the recent advances in the therapeutic effects and molecular mechanisms of key common bioactive compounds from Chinese herbal medicine. Based on the theories of traditional Chinese medicine related to lung diseases, we searched several electronic databases to determine the high-frequency Chinese medicines in clinical application. The active compounds and metabolites from the selected medicines were identified using the Traditional Chinese Medicine Systems Pharmacology Database (TCMSP) by analyzing oral bioavailability and drug similarity index. Then, the pharmacological effects and molecular mechanisms of the selected bioactive compounds in the viral and bacterial infections, inflammation, acute lung injury (ALI), chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, asthma, and lung cancer were summarized. We found that 31 bioactive compounds from the selected 10 common Chinese herbs, such as epigallocatechin-3-gallate (EGCG), kaempferol, isorhamnetin, quercetin, and β-sitosterol, can mainly regulate NF-κB, Nrf2/HO-1, NLRP3, TGF-β/Smad, MAPK, and PI3K/Akt/mTOR pathways to inhibit infection, inflammation, extracellular matrix deposition, and tumor growth in a series of lung-related diseases. This review provides novel perspectives on the preclinical study and clinical application of Chinese herbal medicines and their bioactive compounds against respiratory diseases.