Phloretin attenuates mucus hypersecretion and airway inflammation induced by cigarette smoke

Mechanisms and potential roles of active ingredients of traditional Chinese medicine in the treatment of chronic obstructive pulmonary disease

OBJECTIVES

Chronic obstructive pulmonary disease (COPD) is a respiratory condition with high rates of morbidity and mortality. Recent studies have shown that the increasing research on Traditional Chinese Medicine (TCM) also plays an important role in COPD. The purpose of this review is to categorize TCM and its active ingredients and to summarize their pharmacological effects.

METHODS

Articles published up to December 2024 were searched through PubMed, X-MOL, and the China National Knowledge Infrastructure. The keywords included TCM and its combination with COPD, pharmacologic activity, anti-inflammatory effects, pharmacology, as well as in vivo and in vitro studies.

KEY FINDINGS

Thus far, we have summarized the progress of research on the mechanisms of action of TCM and its active ingredients, such as flavonoids, terpenoids, and phenols, in the treatment of COPD. These mechanisms encompass the reduction of inflammatory responses and lung injury, regulation of the oxidation-antioxidation balance, and modulation of cellular apoptosis and aging, among other effects.

CONCLUSION

TCM and its active ingredients demonstrate strong anti-COPD properties. This provides a reference for accelerating the development of herbal components for the treatment of COPD and for exploring new potential multi-target therapeutic mechanisms. This will mitigate the geographical limitations of using TCM and enhance its application in future management strategies.

Mucus and mucin: changes in the mucus barrier in disease states

In this review we discuss mucus, the viscoelastic secretion from goblet or mucous producing cells that covers and protects all non-keratinized wet epithelial surfaces. In addition to the surface of organs directly contacting with the external environment such as the eyes, this layer provides protection to the underlying gastrointestinal, respiratory and female reproductive tracts by trapping pathogens, irritants, environmental fine particles and potentially harmful foreign substances. Mucins, the primary structural components of mucus, form structurally different mucus layers at different sites in a process regulated by a variety of factors. Currently, more and more studies have shown that the mucus barrier is not only closely related to various intestinal mucus diseases, but also involved in the occurrence and development of various airway diseases and mucus-related diseases, thus it may become a new target for the treatment of various related diseases in the future. Since the dysfunction of the mucous layer is closely related to various pathological processes, in-depth understanding of its molecular mechanism and physiological role is of great theoretical and practical significance for disease prevention and treatment. Here, we discuss different aspects of the mucus layer by focusing on its chemical composition, synthetic pathways, and some of the characteristics of the mucus layer in physiological and pathological situations.

NR1D1 mitigates IL-17a-induced small airway remodeling in biomass smoke-induced COPD

INTRODUCTION

Biomass smoke (BS) exposure is a critical environmental risk factor for Chronic Obstructive Pulmonary Disease (COPD). In this study, mechanisms of biomass smoke (BS)-induced small airway disease are explored, with a focus on the roles of Interleukin-17a (IL-17a) and Nuclear Receptor Subfamily 1 Group D Member 1 (NR1D1).

METHODS

This study included 20 BS exposure COPD (BS-COPD) patients and 13 controls, who underwent chest high-resolution computed tomography (HRCT) scans to assess emphysema and small airway disease. The control group was divided into a low- and high BS exposure control group. Serum IL-17a levels were measured. Wild-type and IL-17a-/- B6/C57 mice were exposed to wood smoke to establish a COPD model in mice. Airway pathology was evaluated by histological analysis. The effects of IL-17a and NR1D1 on cell proliferation of BEAS-2b cells exposed to wood smoke particulate matter 2.5 were assessed in vitro using flow cytometry and Western blotting.

RESULTS

HRCT revealed significantly higher small airway disease and emphysema in BS-COPD patients compared to controls (p < 0.01). Small airway disease exhibited the strongest negative correlation with FEV1%predicted (r = -0.61, p = 0.004). High-exposure control group showed significant BS Index correlations with small airway disease (r = 0.81, p = 0.049) and emphysema (r = 0.87, p = 0.025). Serum IL-17a levels correlated with small airway disease in BS-COPD (r = 0.48, p = 0.033). The mouse model demonstrated higher airway wall thickness and small airway disease in IL-17a-/- mice exposed to wood smoke. In vitro, IL-17a promoted BEAS-2b cell proliferation, an effect enhanced by NR1D1 downregulation.

CONCLUSIONS

BS exposure drives emphysema and small airway disease in non-COPD individuals. NR1D1 downregulation exacerbates IL-17a-mediated remodeling in vitro, suggesting therapeutic potential.

TRIAL REGISTRATION

ChiCTR-OOC-16008692.

Research advances in polyphenols from Chinese herbal medicine for the prevention and treatment of chronic obstructive pulmonary disease: a review

Chronic obstructive pulmonary disease (COPD) is a global health problem due to its high death and morbidity worldwide, which is characterized by an incompletely reversible limitation in airflow that is not fully reversible. Unfortunately, Western medical treatments are unable to reverse the progressive decline in lung function. Importantly, polyphenolic compounds isolated from Chinese herbal medicine exhibited therapeutic/interventional effects on COPD in preclinical studies. This review systematically analyzed the pathogenesis of COPD, such as inflammation, oxidative stress, protease/antiprotease imbalance, aging, cell death, and dysbiosis of gut microbiota. Moreover, this review summarized the regulatory mechanisms of natural polyphenolic compounds for the treatment of COPD. Several studies have demonstrated that natural polyphenolic compounds have therapeutic effects on COPD by regulating various biological processes, such as anti-inflammatory, reduction of oxidative damage, anti-cell death, and inhibition of airway hyperglycemia. Mechanistically, this review found that the promising effects of natural polyphenolic compounds on COPD were mainly achieved through modulating the NF-κB and MAPK inflammatory pathways, the Nrf2 oxidative stress pathway, and the SIRT1/PGC-1α lung injury pathway. Furthermore, this review analyzed the efficacy and safety of natural polyphenolic compounds for the treatment of COPD in clinical trials, and discussed their challenges and future development directions. In conclusion, this review combined the latest literature to illustrate the various pathogenesis and interrelationships of COPD in the form of graphs, texts, and tables, and sorted out the functional role and mechanisms of natural polyphenols in treating COPD, with a view to providing new ideas and plans for the in-depth research on COPD and the systemic treatment of COPD with Chinese herbal medicine.

Amelioration of Inflammation in Rats with Experimentally Induced Asthma by Spenceria ramalana Trimen Polyphenols via the PI3K/Akt Signaling Pathway

Asthma is a chronic inflammatory respiratory disease that affects millions globally and poses a serious public health challenge. Current therapeutic strategies, including corticosteroids, are constrained by variable patient responses and adverse effects. In this study, a polyphenolic extract derived from the Tibetan medicinal plant Spenceria ramalana Trimen (SRT) was employed and shown to improve experimentally (ovalbumin + cigarette smoke, OVA + CS) induced asthma in rats. Initially, the potential therapeutic mechanism of the polyphenolic components in SRT on OVA + CS-induced asthma was predicated by network pharmacology analysis. Subsequently, in vivo experiments identified that SRT polyphenols exhibit significant anti-asthmatic activities, primarily mediated by lowering inflammatory cell counts such as the WBC (white blood cell), eosinophils, and neutrophils, decreasing the expression of inflammatory cytokines (IL-4, IL-5, IL-13, and TNF-α), alleviating lung histological damage (reduced inflammation, collagen deposition, and mucus secretion), and enhancing the epithelial barrier integrity (upregulation of ZO-1, occludin, and claudin-1). Additionally, SRT polyphenols downregulated the PI3K/Akt (Phosphoinositide 3-kinase/protein kinase B) signaling pathway, improved gut microbiota disruption, and regulated fecal metabolites (glucose-6-glutamate, PS (16:0/0:0), 8-aminocaprylic acid, galactonic acid, Ascr#10, 2,3,4,5,6,7-hexahydroxyheptanoic acid, phosphodimethylethanolamine, muramic acid, 9-oxohexadeca-10e-enoic acid, and sedoheptulose) in asthmatic rats. In conclusion, SRT polyphenols exerted multifaceted protective effects against OVA + CS-induced asthma in rats, highlighting their potential value in preventing asthma via the PI3K/Akt signaling pathway.

Effects of Phaffia rhodozyma on microbial community dynamics and tobacco quality during tobacco fermentation

Introduction

Carotenoids are important precursors of various aroma components in tobacco and play an important role in the sensory quality of tobacco. Phaffia rhodozyma is a species of Xanthophyllomyces capable of synthesizing a highly valuable carotenoid-astaxanthin, but has not yet been used in improving tobacco quality.

Methods

The dynamic changes of microbial community and metabolites during tobacco fermentation were analyzed in combination with microbiome and metabolome, and the quality of tobacco after fermentation was evaluated by sensory scores.

Results

P. rhodozyma could grow and produce carotenoids in tobacco extract, with a maximum biomass of 6.50 g/L and a maximum carotenoid production of 36.13 mg/L at 100 g/L tobacco extract. Meanwhile, the correlation analysis combined with microbiome and metabolomics showed that P. rhodozyma was significantly positively correlated with 11 metabolites such as 6-hydroxyluteolin and quercetin. Furthermore, the contents of alcohols, ketones and esters, which were important aromatic components in fermented tobacco, reached 77.57 μg/g, 58.28 μg/g and 73.51 μg/g, increasing 37.39%, 265.39% and 266.27% compared to the control group, respectively. Therefore, the aroma and flavor, and taste scores of fermented tobacco increased by 0.5 and 1.0 points respectively.

Discussion

This study confirmed that P. rhodozyma fermentation could effectively improve the sensory evaluation of tobacco, and provided a novel microbial fermentation method to improve tobacco quality.

Phloretin inhibits transmissible gastroenteritis virus proliferation via multiple mechanisms

Transmissible gastroenteritis virus (TGEV), an enteropathogenic coronavirus, has caused huge economic losses to the pig industry, with 100% mortality in piglets aged 2 weeks and intestinal injury in pigs of other ages. However, there is still a shortage of safe and effective anti-TGEV drugs in clinics. In this study, phloretin, a naturally occurring dihydrochalcone glycoside, was identified as a potent antagonist of TGEV. Specifically, we found phloretin effectively inhibited TGEV proliferation in PK-15 cells, dose-dependently reducing the expression of TGEV N protein, mRNA, and virus titer. The anti-TGEV activity of phloretin was furthermore refined to target the internalization and replication stages. Moreover, we also found that phloretin could decrease the expression levels of proinflammatory cytokines induced by TGEV infection. In addition, we expanded the potential key targets associated with the anti-TGEV effect of phloretin to AR, CDK2, INS, ESR1, ESR2, EGFR, PGR, PPARG, PRKACA, and MAPK14 with the help of network pharmacology and molecular docking techniques. Furthermore, resistant viruses have been selected by culturing TGEV with increasing concentrations of phloretin. Resistance mutations were reproducibly mapped to the residue (S242) of main protease (Mpro). Molecular docking analysis showed that the mutation (S242F) significantly disrupted phloretin binding to Mpro, suggesting Mpro might be a potent target of phloretin. In summary, our findings indicate that phloretin is a promising drug candidate for combating TGEV, which may be helpful for developing pharmacotherapies for TGEV and other coronavirus infections.

Honokiol ameliorates cigarette smoke-induced damage of airway epithelial cells via the SIRT3/SOD2 signalling pathway

Cigarette smoking can cause damage of airway epithelial cells and contribute to chronic obstructive pulmonary disease (COPD). Honokiol is originally isolated from Magnolia obovata with multiple biological activities. Here, we investigated the protective effects of honokiol on cigarette smoke extract (CSE)-induced injury of BEAS-2B cells. BEAS-2B cells were treated with 300 mg/L CSE to construct an in vitro cell injury model, and cells were further treated with 2, 5 and 10 μM honokiol, then cell viability and LDH leakage were analysed by CCK-8 and LDH assay kits, respectively. Apoptosis was detected by flow cytometry analysis. ELISA was used to measure the levels of tumour necrosis factor (TNF)-ɑ, IL-1β, IL-6, IL-8 and MCP-1. The results showed that honokiol (0.5-20 μM) showed non-toxic effects on BEAS-2B cells. Treatment with honokiol (2, 5 and 10 μM) reduced CSE (300 mg/L)-induced decrease in cell viability and apoptosis in BEAS-2B cells. Honokiol also decreased CSE-induced inflammation through inhibiting expression and secretion of inflammatory cytokines, such as TNF-ɑ, IL-1β, IL-6, IL-8 and MCP-1. Moreover, honokiol repressed CSE-induced reactive oxygen species (ROS) production, decrease of ATP content and mitochondrial biogenesis, as well as mitochondrial membrane potential. Mechanistically, honokiol promoted the expression of SIRT3 and its downstream target genes, which are critical regulators of mitochondrial function and oxidative stress. Silencing of SIRT3 reversed the protective effects of honokiol on CSE-induced damage and mitochondrial dysfunction in BEAS-2B cells. These results indicated that honokiol attenuated CSE-induced damage of airway epithelial cells through regulating SIRT3/SOD2 signalling pathway.

Anti-inflammatory effects of acupuncture in the treatment of chronic obstructive pulmonary disease

Numerous randomised controlled trials have suggested the positive effects of acupuncture on chronic obstructive pulmonary disease (COPD). However, the underlying therapeutic mechanisms of acupuncture for COPD have not been clearly summarized yet. Inflammation is central to the development of COPD. In this review, we elucidate the effects and underlying mechanisms of acupuncture from an anti-inflammatory perspective based on animal studies. Cigarette smoke combined with lipopolysaccharide is often used to establish animal models of COPD. Electroacupuncture can be an effective intervention to improve inflammation in COPD, and Feishu (BL13) and Zusanli (ST36) can be used as basic acupoints in COPD animal models. Different acupuncture types can regulate different types of inflammatory cytokines; meanwhile, different acupuncture types and acupoint options have similar effects on modulating the level of inflammatory cytokines. In particular, acupuncture exerts anti-inflammatory effects by inhibiting the release of inflammatory cells, inflammasomes and inflammatory cytokines. The main underlying mechanism through which acupuncture improves inflammation in COPD is the modulation of relevant signalling pathways: nuclear factor-κB (NF-κB) (e.g., myeloid differentiation primary response 88/NF-κB, toll-like receptor-4/NF-κB, silent information regulator transcript-1/NF-κB), mitogen-activated protein kinase signalling pathways (extracellular signal-regulated kinase 1/2, p38 and c-Jun NH2-terminal kinase), cholinergic anti-inflammatory pathway, and dopamine D2 receptor pathway. The current synthesis will be beneficial for further research on the effect of acupuncture on COPD inflammation. Please cite this article as: Jiang LH, Li PJ, Wang YQ, Jiang ML, Han XY, Bao YD, Deng XL, Wu WB, Liu XD. Anti-inflammatory effects of acupuncture in the treatment of chronic obstructive pulmonary disease. J Integr Med. 2023; 21(6): 518-527.

Roles of autophagy-related genes in the therapeutic effects of Xuanfei Pingchuan capsules on chronic obstructive pulmonary disease based on transcriptome sequencing analysis

Objective: Autophagy plays an important role in the occurrence and development of chronic obstructive pulmonary disease (COPD). We evaluated the effect of Xuanfei Pingchuan capsule (XFPC) on autophagy-related genes of COPD by a bioinformatics analysis and experimental verification. Methods: The best treatment duration was screened by CCK8 assays. HBE cells were divided into three groups: blank, CSE and XFPC. After intervened by XFPC, HBE cells were collected and sent to Shenzhen Huada Gene Company for transcriptome sequencing. Subsequently, differential expression analyses, target gene prediction, and function enrichment analyses were carried out. Expression changes were verified in HBE cells by real-time Quantitative PCR (RT-qPCR) and western blotting (WB). Results: The result of differential expression analysis displayed that 125 target genes of HBE cells were mainly related to mitogen-activated protein kinase (MKK) binding, interleukin 33 binding, 1-Pyrroline-5-carboxylate dehydrogenase activity, and the mitogen-activated protein kinase (MAPK) signal pathway. Among the target genes, the core genes related to autophagy obtained by maximum neighborhood component algorithm were CSF1, AREG, MAPK9, MAP3K7, and AKT3. RT-qPCR and WB methods were used to verify the result, it showed similar expression changes in CSF1, MAPK9, MAP3K7, and AKT3 in bronchial epithelial cells to those in the bioinformatics analysis. Conclusion: Through transcriptome sequencing and validation analysis, we predicted that CSF1, MAPK9, MAP3K7, and AKT3 may be the potential autophagy-related genes that play an important role in the pathogenesis of COPD. XFPC may regulate autophagy by down-regulating the expression of CSF1, MAPK9, MAP3K7, and AKT3, thus achieving the purpose of treating chronic obstructive pulmonary disease.

Effects of Z-VaD-Ala-Asp-Fluoromethyl Ketone (Z-VAD-FMK) and Acetyl-Asp-Glu-Val-Asp-Aldehyde(Ac-DEVD-CHO) on Inflammation and Mucus Secretion in Mice Exposed to Cigarette Smoke

Background and Objectives

Smoking can lead to airway inflammation and mucus secretion through the nucleotide-binding domain-like receptor protein 3/caspase-1 pathway. In this study, z-VaD-Ala-Asp-fluoromethyl ketone(Z-VAD), a pan-caspase inhibitor, and acetyl-Asp-Glu-Val-Asp-aldehyde(Ac-DEVD), a caspase-3 inhibitor, were used to investigate the effect of caspase inhibitors on the expression of interleukin(IL)-1β and IL-8, airway inflammation, and mucus secretion in mice exposed to cigarette smoke(CS).

Methods

Thirty-two C57BL/6J male mice were divided into a control group, Smoke group, Z-VAD group, and Ac-DEVD group. Except for the control group, the animals were all exposed to CS for three months. After the experiment, lung function was measured and hematoxylin and eosin staining and periodic acid-Schiff staining were performed. The levels of IL-1β, IL-8, and mucin 5ac(Muc5ac) in serum and bronchoalveolar lavage fluid(BALF) were determined by enzyme-linked immunosorbent assay.

Results

Compared with the control group, the lung function of mice exposed to smoke was poorer, with a large number of inflammatory cells infiltrating around the airway, collapse of alveoli, expansion and fusion of distal alveoli, and formation of emphysema. The Z-VAD group was relieved compared with the smoke group. Airway inflammation was also reduced in the Ac-DEVD group compared with the Smoke group, but the degree of emphysema was not significantly improved. Although Z-VAD relieved airway inflammation and emphysema, Ac-DEVD only relieved inflammation. Z-VAD and Ac-DEVD decreased serum IL-1β and IL-8 levels. In BALF, IL-1β was decreased in Z-VAD group and IL-8 was highest in Smoke +Ac-DEVD group compared with control group and Ac-DEVD group. There was no significant difference in the expression of Muc5ac in serum. However, in BALF, levels of Muc5ac were higher in the smoking group and the lowest in the Ac-DEVD group.

Conclusion

Mice exposed to smoke had decreased lung function and significant cilia lodging, epithelial cell shedding, and inflammatory cell infiltration, with significant emphysema formation. The pan-caspase inhibitor, Z-VAD, improved airway inflammation and emphysema lesions in the mice exposed to smoke and reduced IL-1β and IL-8 levels in serum. The caspase-3 inhibitor, Ac-DEVD, reduced airway inflammation, serum IL-1β and IL-8 levels, and Muc5ac levels in BALF, but it did not improve emphysema.

The Molecular Pharmacology of Phloretin: Anti-Inflammatory Mechanisms of Action

The isolation of phlorizin from the bark of an apple tree in 1835 led to a flurry of research on its inhibitory effect on glucose transporters in the intestine and kidney. Using phlorizin as a prototype drug, antidiabetic agents with more selective inhibitory activity towards glucose transport at the kidney have subsequently been developed. In contrast, its hydrolysis product in the body, phloretin, which is also found in the apple plant, has weak antidiabetic properties. Phloretin, however, displays a range of pharmacological effects including antibacterial, anticancer, and cellular and organ protective properties both in vitro and in vivo. In this communication, the molecular basis of its anti-inflammatory mechanisms that attribute to its pharmacological effects is scrutinised. These include inhibiting the signalling pathways of inflammatory mediators' expression that support its suppressive effect in immune cells overactivation, obesity-induced inflammation, arthritis, endothelial, myocardial, hepatic, renal and lung injury, and inflammation in the gut, skin, and nervous system, among others.

Integrating Network Pharmacology and Experimental Validation to Explore the Pharmacological Mechanism of Astragaloside IV in Treating Bleomycin-Induced Pulmonary Fibrosis

Purpose

Our study aims to reveal the pharmacological mechanism of Astragaloside IV in the treatment of pulmonary fibrosis(PF) through network pharmacology and experimental validation.

Methods

We first determined the in vivo anti-pulmonary fibrosis effect of Astragaloside IV by HE, MASSON staining, and lung coefficients, then used network pharmacology to predict the signaling pathways and molecularly docked key pathway proteins, and finally validated the results by in vivo and in vitro experiments.

Results

In in vivo experiments, we found that Astragaloside IV improved body weight (P < 0.05), increased lung coefficients (P < 0.05), and reduced lung inflammation and collagen deposition in mice with pulmonary fibrosis. The network pharmacology results showed that Astragaloside IV had 104 cross-targets with idiopathic pulmonary fibrosis, and the results of KEGG enrichment analysis indicated that cellular senescence could be an important pathway for Astragaloside IV in the treatment of pulmonary fibrosis. Astragaloside IV also bound well to senescence-associated proteins, according to molecular docking results. The results of both in vivo and in vitro experiments showed that Astragaloside IV significantly inhibited senescence protein markers such as P53, P21, and P16 and delayed cellular senescence (P < 0.05). In in vivo experiments, we also found that Astragaloside IV reduced the production of SASPs (P < 0.05), and in in vitro experiments, Astragaloside IV also reduced the production of ROS. In addition, by detecting epithelial-mesenchymal transition(EMT)-related marker protein expression, we also found that Astragaloside IV significantly inhibited the development of EMT in both in vivo and in vitro experiments (P < 0.05).

Conclusion

Our research found that Astragaloside IV could alleviate bleomycin-induced PF by preventing cellular senescence and EMT.

Polyphenols, flavonoids and inflammasomes: the role of cigarette smoke in COPD

COPD is predicted to become the third leading cause of morbidity and mortality worldwide by 2030. Cigarette smoking (active or passive) is one of its chief causes, with about 20% of cigarette smokers developing COPD from cigarette smoke (CS)-induced irreversible damage and sustained inflammation of the airway epithelium. Inflammasome activation leads to the cleavage of pro-interleukin (IL)-1β and pro-IL-18, along with the release of pro-inflammatory cytokines via gasdermin D N-terminal fragment membrane pores, which further triggers acute phase pro-inflammatory responses and concurrent pyroptosis. There is currently intense interest in the role of nucleotide-binding oligomerisation domain-like receptor family, pyrin domain containing protein-3 inflammasomes in chronic inflammatory lung diseases such as COPD and their potential for therapeutic targeting. Phytochemicals including polyphenols and flavonoids have phyto-medicinal benefits in CS-COPD. Here, we review published articles from the last decade regarding the known associations between inflammasome-mediated responses and ameliorations in pre-clinical manifestations of CS-COPD via polyphenol and flavonoid treatment, with a focus on the underlying mechanistic insights. This article will potentially assist the development of drugs for the prevention and therapy of COPD, particularly in cigarette smokers.

This review compiles current investigations into the role of polyphenols/flavonoids in the alleviation of cigarette smoke-induced inflammasome; notably it provides a promising hit for rectifying the treatment of COPD.https://bit.ly/36OcUO9

Cocoa Bar Antioxidant Profile Enrichment with Underutilized Apples Varieties

The impact of dried apples (Malus × domestica Borkh.) addition on improving the antioxidant characteristics of dark chocolate was evaluated. The antioxidant activity was measured through DPPH scavenging activity and showed an increase in the cocoa bar with 'Nesta' dry apple (17.3% vs. 46.8%) in comparison to cocoa mass. The 15 polyphenols analyzed by UHPLC-ESI-MS/MS indicated great variability among the apple varieties. Quercetin was detected in the highest concentrations (ranged from 753.3 to 1915.5 µg g-1), while the lowest were for kaempferol 7-O-glucoside, measured only in 'Mora' and 'Nesta' cocoa bars (from 0.034 to 0.069 µg g-1, respectively). P-coumaric acid, trans-ferulic acid, and chlorogenic acid contribute largely to the antioxidant activity in cocoa bars. Principal component analysis shows that a cocoa bar with the addition of 'Nesta' dry apple differ from others due to its higher content of polyphenols (1614 ± 61.8 mg gallic acid equivalents per 100 g). In conclusion, data confirm that cocoa bars with dry apples might be considered as a polyphenol-enriched food.

Potential Natural Small Molecular Compounds for the Treatment of Chronic Obstructive Pulmonary Disease: An Overview

Chronic obstructive pulmonary disease (COPD) is one of the major diseases threatening human life and health. According to the report released by the World Health Organization (WHO) in 2020, COPD has become the third leading cause of death in the world, featuring a sustainable growth of incidence rate as well as population age. The purpose of this review focuses on the advancement of bioactive natural compounds, such as baicalin, quercetin, resveratrol, and curcumin, which demonstrate promising therapeutic/interventional effects on CODP in vitro and in vivo. Information emphasizing on COPD was systematically collected from several authoritative internet databases including Web of Science, PubMed, Elsevier, Wiley Online Library, and Europe PMC, with a combination of keywords containing “COPD” and “natural small molecular compounds”. The new evidence indicated that these valuable molecules featured unique functions in the treatment of COPD through various biological processes such as anti-inflammatory, anti-oxidant, anti-apoptosis, and anti-airway fibrosis. Moreover, we found that the promising effects of these natural compounds on COPD were mainly achieved through JAK3/STAT3/NF-κB and MAPK inflammatory signaling pathways, Nrf2 oxidative stress signaling pathway, and TGF-β1/Smad 2/3 fibrosis signaling pathway, which referenced to multiple targets like TNF-α, IL-6, IL-8, TIMP-1, MMP, AKT, JAK3, IKK, PI3K, HO-1, MAPK, P38, ERK, etc. Current challenges and future directions in this promising field are also discussed at the end of this review. For the convenience of the readers, this review is divided into ten parts according to the structures of potential natural small molecular compounds. We hope that this review brings a quick look and provides some inspiration for the research of COPD.

Recent advancements and application of in vitro models for predicting inhalation toxicity in humans

Animals have been indispensable in testing chemicals that can pose a risk to human health, including those delivered by inhalation. In recent years, the combination of societal debate on the use of animals in research and testing, the drive to continually enhance testing methodologies, and technology advancements have prompted a range of initiatives to develop non-animal alternative approaches for toxicity testing. In this review, we discuss emerging in vitro techniques being developed for the testing of inhaled compounds. Advanced tissue models that are able to recreate the human response to toxic exposures alongside examples of their ability to complement in vivo techniques are described. Furthermore, technology being developed that can provide multi-organ toxicity assessments are discussed.

Antimicrobial and Anti-Inflammatory Activity of Apple Polyphenol Phloretin on Respiratory Pathogens Associated With Chronic Obstructive Pulmonary Disease

Bacterial infections contribute to accelerated progression and severity of chronic obstructive pulmonary disease (COPD). Apples have been associated with reduced symptoms of COPD and disease development due to their polyphenolic content. We examined if phloretin, an apple polyphenol, could inhibit bacterial growth and inflammation induced by the main pathogens associated with COPD. Phloretin displayed bacteriostatic and anti-biofilm activity against nontypeable Haemophilus influenzae (NTHi), Moraxella catarrhalis, Streptococcus pneumoniae, and to a lesser extent, Pseudomonas aeruginosa. In vitro, phloretin inhibited NTHi adherence to NCI-H292 cells, a respiratory epithelial cell line. Phloretin also exhibited anti-inflammatory activity in COPD pathogen-induced RAW 264.7 macrophages and human bronchial epithelial cells derived from normal and COPD diseased lungs. In mice, NTHi bacterial load and chemokine (C-X-C motif) ligand 1 (CXCL1), a neutrophil chemoattractant, was attenuated by a diet supplemented with phloretin. Our data suggests that phloretin is a promising antimicrobial and anti-inflammatory nutraceutical for reducing bacterial-induced injury in COPD.

Low molecular weight fucoidan attenuating pulmonary fibrosis by relieving inflammatory reaction and progression of epithelial-mesenchymal transition

Diffuse alveolar injury and pulmonary fibrosis (PF) are the main causes of death of Covid-19 cases. In this study a low molecular weight fucoidan (LMWF) with unique structural was obtained from Laminaria japonica, and its anti- PF and anti-epithelial-mesenchymal transition (EMT) bioactivity were investigated both in vivo and in vitro. After LWMF treatment the fibrosis and inflammatory factors stimulated by Bleomycin (BLM) were in lung tissue. Immunohistochemical and Western-blot results found the expression of COL2A1, β-catenin, TGF-β, TNF-α and IL-6 were declined in mice lung tissue. Besides, the phosphorylation of PI3K and Akt were inhibited by LMWF. In addition, the progression of EMT induced by TGF-β1 was inhibited by LMWF through down-regulated both TGF-β/Smad and PI3K/AKT signaling pathways. These data indicate that unique LMWF can protect the lung from fibrosis by weakening the process of inflammation and EMT, and it is a promising therapeutic option for the treatment of PF.

Mitochondrial-Targeting Antioxidant SS-31 Suppresses Airway Inflammation and Oxidative Stress Induced by Cigarette Smoke

This study investigated whether the mitochondrial-targeted peptide SS-31 can protect against cigarette smoke- (CS-) induced airway inflammation and oxidative stress in vitro and in vivo. Mice were exposed to CS for 4 weeks to establish a CS-induced airway inflammation model, and those in the experimental group were pretreated with SS-31 1 h before CS exposure. Pathologic changes and oxidative stress in lung tissue, inflammatory cell counts, and proinflammatory cytokine levels in bronchoalveolar lavage fluid (BALF) were examined. The mechanistic basis for the effects of SS-31 on CS extract- (CSE-) induced airway inflammation and oxidative stress was investigated using BEAS-2B bronchial epithelial cells and by RNA sequencing and western blot analysis of lung tissues. SS-31 attenuated CS-induced inflammatory injury of the airway and reduced total cell, neutrophil, and macrophage counts and tumor necrosis factor- (TNF-) α, interleukin- (IL-) 6, and matrix metalloproteinase (MMP) 9 levels in BALF. SS-31 also attenuated CS-induced oxidative stress by decreasing malondialdehyde (MDA) and myeloperoxidase (MPO) activities and increasing that of superoxide dismutase (SOD). It also reversed CS-induced changes in the expression of mitochondrial fission protein (MFF) and optic atrophy (OPA) 1 and reduced the amount of cytochrome c released into the cytosol. Pretreatment with SS-31 normalized TNF-α, IL-6, and MMP9 expression, MDA and SOD activities, and ROS generation in CSE-treated BEAS-2B cells and reversed the changes in MFF and OPA1 expression. RNA sequencing and western blot analysis showed that SS-31 inhibited CS-induced activation of the mitogen-activated protein kinase (MAPK) signaling pathway in vitro and in vivo. Thus, SS-31 alleviates CS-induced airway inflammation and oxidative stress via modulation of mitochondrial function and regulation of MAPK signaling and thus has therapeutic potential for the treatment of airway disorders caused by smoking.

Effect of phloretin on growth performance, serum biochemical parameters and antioxidant profile in heat-stressed broilers

The objective of this work was to evaluate the effect of phloretin on growth performance, serum biochemical parameters, antioxidant profile, glutathione (GSH)-related enzymes, nuclear factor erythroid 2-related 2 (Nrf2) and heat shock protein 70 (HSP70) in heat-stressed broilers. A total of 240, 22-day-old Arbor Acres broilers were divided into 4 groups. The control group was housed at 23.0 ± 0.61°C and fed with basal diet, while the 3 heat-stressed groups (A, B, and C groups) were housed at 30.5 ± 0.69°C and fed with basal diet containing 0, 100, and 200 mg/kg phloretin, respectively. Serum was taken form 42-day-old broilers. Results showed that heat stress decreased (P < 0.05) the final body weight (FBW), body weight gain (BWG), feed intake (FI), serum total protein (TP), triglyceride (TG), triiodothyronine (T3), thyroxine (T4), GSH, catalase (CAT), and total antioxidant capacity (T-AOC) levels, but increased (P < 0.05) the feed-to-gain ratio (FGR) and serum malondialdehyde (MDA) levels in broilers compared with that in the control group. Among the heat-stressed groups, supplementary 200 mg/kg phloretin increased (P < 0.05) the FBW, BWG, FI, serum TP, TG, T4, GSH, CAT, and T-AOC levels, and decreased (P < 0.05) the FGR and serum MDA in broilers. There were significant decreases (P < 0.05) in the glutathione peroxidase (GSH-Px), γ-glutamylcysteine synthetase (γ-GCS), and Nrf2, but significant increases (P < 0.05) in the HSP70 of the broiler serum after heat stress treatment. Among the heat-stressed groups, supplementary 200 mg/kg phloretin increased (P < 0.05) the GSH-Px, γ-GCS, and Nrf2 levels, but decreased (P < 0.05) the serum HSP70 level in the heat-stressed broilers. Under high temperature condition, FBW, BWG, FI, FGR, serum TP, TG, T4, MDA, GSH, CAT, T-AOC, GSH-Px, γ-GCS, Nrf2 and HSP70 were linearly affected by inclusion of phloretin. These results indicated that phloretin may improve growth performance, serum parameters, and antioxidant profiles through regulated GSH-related enzymes, Nrf2 and HSP70 in heat-stressed broilers.

MERTK Inhibition: Potential as a Treatment Strategy in EGFR Tyrosine Kinase Inhibitor-Resistant Non-Small Cell Lung Cancer

Epidermal growth factor tyrosine kinase inhibitors (EGFR-TKIs) are currently the most effective treatment for non-small cell lung cancer (NSCLC) patients, who carry primary EGFR mutations. However, the patients eventually develop drug resistance to EGFR-TKIs after approximately one year. In addition to the acquisition of the EGFR T790M mutation, the activation of alternative receptor-mediated signaling pathways is a common mechanism for conferring the insensitivity of EGFR-TKI in NSCLC. Upregulation of the Mer receptor tyrosine kinase (MERTK), which is a member of the Tyro3-Axl-MERTK (TAM) family, is associated with a poor prognosis of many cancers. The binding of specific ligands, such as Gas6 and PROS1, to MERTK activates phosphoinositide 3-kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK) cascades, which are the signaling pathways shared by EGFR. Therefore, the inhibition of MERTK can be considered a new therapeutic strategy for overcoming the resistance of NSCLC to EGFR-targeted agents. Although several small molecules and monoclonal antibodies targeting the TAM family are being developed and have been described to enhance the chemosensitivity and converse the resistance of EGFR-TKI, few have specifically been developed as MERTK inhibitors. The further development and investigation of biomarkers which can accurately predict MERTK activity and the response to MERTK inhibitors and MERTK-specific drugs are vitally important for obtaining appropriate patient stratification and increased benefits in clinical applications.

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

Chronic obstructive pulmonary disease (COPD) is a common respiratory disease with high morbidity and mortality. The conventional therapies remain palliative and have various undesired effects. Flavonoids from traditional Chinese medicine (TCM) have been proved to exert protective effects on COPD. This review aims to illuminate the poly-pharmacological properties of flavonoids in treating COPD based on laboratory evidences and clinical data and points out possible molecular mechanisms. Animal/laboratory studies and randomised clinical trials about administration of flavonoids from TCM for treating COPD from January 2010 to October 2020 were identified and collected, with the following terms: chronic obstructive pulmonary disease or chronic respiratory disease or inflammatory lung disease, and flavonoid or nature product or traditional Chinese medicine. Pharmacokinetic studies and external application treatment were excluded. A total of 15 flavonoid compounds were listed. Flavonoids could inhibit inflammation, oxidative stress, and cellular senescence, restore corticosteroid sensitivity, improve pulmonary histology, and boost pulmonary function through regulating multiple targets and signaling pathways, which manifest that flavonoids are a group of promising natural products for COPD. Nevertheless, most studies remain in the research phase of animal testing, and further clinical applications should be carried out.

Phloretin, an Apple Polyphenol, Inhibits Pathogen-Induced Mucin Overproduction

SCOPE

Bacterial infection induces mucus overproduction, contributing to acute exacerbations and lung function decline in chronic respiratory diseases. A diet enriched in apples may provide protection from pulmonary disease development and progression. This study examined whether phloretin, an apple polyphenol, inhibits mucus synthesis and secretion induced by the predominant bacteria associated with chronic respiratory diseases.

METHODS AND RESULTS

The expression of mucus constituent mucin 5AC (MUC5AC) in FVB/NJ mice and NCI-H292 epithelial cells is analyzed. Nontypeable Haemophilus influenzae (NTHi)-infected mice developed increased MUC5AC mRNA, which a diet containing phloretin inhibited. In NCI-H292 cells, NTHi, Moraxella catarrhalis, Streptococcus pneumoniae, and Pseudomonas aeruginosa increased MUC5AC mRNA, which phloretin inhibited. Phloretin also diminished NTHi-induced MUC5AC protein secretion. NTHi-induced increased MUC5AC required toll-like receptor 4 (TLR4) and NADH oxidase 4 (NOX4) signaling and subsequent activation of the epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK) pathway. Phloretin inhibited NTHi-induced TLR4/NOX4 and EGFR/MAPK signaling, thereby preventing increased MUC5AC mRNA. EGFR activation can also result from increased EGFR ligand synthesis and subsequent ligand activation by matrix metalloproteinases (MMPs). In NCI-H292 cells, NTHi increased EGFR ligand and MMP1 and MMP13 mRNA, which phloretin inhibited.

CONCLUSIONS

In summary, phloretin is a promising therapeutic candidate for preventing bacterial-induced mucus overproduction.

Mitoquinone ameliorates cigarette smoke-induced airway inflammation and mucus hypersecretion in mice

BACKGROUND

Cigarette smoking, which induces airway inflammation and mucus hypersecretion, is a major risk factor for the development of cigarette smoke (CS)-induced airway disorders. In this study, we investigated the effects and mechanisms of mitoquinone (MitoQ), a mitochondria-targeted antioxidant, on CS-induced airway inflammation and mucus hypersecretion in mice.

METHODS

C57BL/6J mice were exposed to CS for 75 min twice daily, 5 days per week for 4 weeks. MitoQ (2.5, 5 mg/kg/day) was administered intraperitoneally 1 h before CS exposure. Bronchoalveolar lavage fluid (BALF) was obtained for cell counting and determination of pro-inflammatory cytokine levels. Lung tissue was collected for histological examination; Western blotting was used to measure levels of Mfn2, Drp1, cytochrome c, NF-κB p65, and IκBα.

RESULTS

Pretreatment with MitoQ significantly attenuated CS-induced thickening of the airway epithelium, peribronchial inflammatory cell infiltration, goblet cell hyperplasia and Muc5ac staining. The numbers of total cells, neutrophils and macrophages, as well as levels of TNF-α and IL-6 in BALF were remarkably decreased by MitoQ in a dose-dependent manner. MitoQ attenuated oxidative stress by preventing the CS-induced increase in malondialdehyde level and decrease in superoxide dismutase activity and GSH/GSSG ratio. MitoQ decreased the expression of mitochondrial fission protein Drp1 and increased that of mitochondrial fusion protein Mfn2, as well as reduced cytochrome c release into the cytosol. Furthermore, MitoQ suppressed IκBα degradation and NF-κB p65 nuclear translocation.

CONCLUSIONS

MitoQ attenuates inflammation, mucus hypersecretion, and oxidative stress induced by CS. It may exert these effects in part by modulating mitochondrial function and the NF-κB signal pathway.

Fisetin Alleviated Bleomycin-Induced Pulmonary Fibrosis Partly by Rescuing Alveolar Epithelial Cells From Senescence

Idiopathic pulmonary fibrosis is an aging-associated disease, satisfactory therapies are not yet available. Accelerated senescence of alveolar epithelial cells plays an important part in Idiopathic pulmonary fibrosis pathogenesis. Fisetin (FIS) is a natural non-toxic flavonoid, which has many pharmacological functions. However, the role of FIS in pulmonary fibrosis has not been established. In this study, we found that FIS treatment apparently alleviated BLM-induced weight loss, inflammatory cells infiltration, inflammatory factors expression, collagen deposition and alveolar epithelial cell senescence, along with AMPK activation and the down regulation of NF-κB and TGF-β/Smad3 in vivo. In vitro, FIS administration significantly inhibited the senescence of alveolar epithelial cells and senescence-associated secretory phenotype, followed by reduced transdifferentiation of fibroblasts to myofibroblasts as well as collagen deposition in fibroblasts, which was blocked by an AMPK inhibitor, Compound C. Together, these results suggest that FIS can alleviate the development of BLM-induced pulmonary fibrosis, which is related to the inhibition of TGF-β/Smad3 signaling and the reduction of alveolar epithelium cell senescence by regulating AMPK/NF-κB signaling pathway. FIS may be a promising candidate for patients with pulmonary fibrosis.

Airborne PAHs inhibit gap junctional intercellular communication and activate MAPKs in human bronchial epithelial cell line

Inhalation exposures to polycyclic aromatic hydrocarbons (PAHs) have been associated with various adverse health effects, including chronic lung diseases and cancer. Using human bronchial epithelial cell line HBE1, we investigated the effects of structurally different PAHs on tissue homeostatic processes, namely gap junctional intercellular communication (GJIC) and MAPKs activity. Rapid (<1 h) and sustained (up to 24 h) inhibition of GJIC was induced by low/middle molecular weight (MW) PAHs, particularly by those with a bay- or bay-like region (1- and 9-methylanthracene, fluoranthene), but also by fluorene and pyrene. In contrast, linear low MW (anthracene, 2-methylanthracene) or higher MW (chrysene) PAHs did not affect GJIC. Fluoranthene, 1- and 9-methylanthracene induced strong and sustained activation of MAPK ERK1/2, whereas MAPK p38 was activated rather nonspecifically by all tested PAHs. Low/middle MW PAHs can disrupt tissue homeostasis in human airway epithelium via structure-dependent nongenotoxic mechanisms, which can contribute to their human health hazards.

Phloretin protects against cardiac damage and remodeling via restoring SIRT1 and anti-inflammatory effects in the streptozotocin-induced diabetic mouse model

Diabetic cardiomyopathy increases the risk of heart failure independent of coronary artery disease and hypertension. Phloretin (PHL) shows anti-inflammatory effects in macrophages. In this study, we explored the protective effects of PHL on high glucose (HG)-induced injury in diabetic cardiomyopathy in vivo and in vitro. Using streptozotocin-induced diabetic mouse model and incubating cardiac cells line under a HG environment, PHL were evaluated of the activities of anti-inflammation and anti-fibrosis. In the study, PHL treatment ameliorated cardiomyocyte inflammation injury, and reduced fibrosis in vivo and in vitro. PHL also improved cardiac biochemical criterions after 8 weeks of induction of diabetes in C57BL/6 mice. Molecular docking results indicated that silent information regulator 2 homolog 1 (SIRT1) bound to PHL directly and that SIRT1 expression was upregulated in the PHL-treated group in HG-induced H9C2 cells. Protective effect of PHL was been eliminated in silence SIRT1 H9C2 cells. Taken together, these results suggested that PHL suppressed HG-induced cardiomyocyte injury via restoring SIRT1 expression.

A Comparative Study on Polyphenolic Composition of Berries from the Tibetan Plateau by UPLC-Q-Orbitrap MS System

Five traditional medicinal food from the Tibetan plateau including Nitraria tangutorum Bobrov (NT), Hippophae rhamnoides L. (HR), Lycium ruthenicum Murray (LR), Lycium barbarum L. (LB) and Rubus corchorifolius L.f. (RC) are rich in phenolic compounds. However, the detailed studies about the phenolic compounds remain scarce. Therefore, we established a rapid method for the simultaneous identification and quantification of the phenolic compounds from berries via Ultra Performance Liquid Chromatography-Quadruple-Orbitrap MS system (UPLC-Q-Orbitrap MS). This method was verified from many aspects including detection limit, quantification limit, precision, repeatability, stability, average recovery rate and recovery range, and then was used to analyze the phenolic compounds in these five species of berries. Finally, a total of 21 phenolic compounds were directly identified by comparing the retention time and exact mass, of which 14 compounds were identified by us for the first time in berries from the Tibetan plateau, including one flavonoid aglycone (myricetin), 11 phenolic acids (gallic acid, protocatechuate, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, 2-hydroxybenzeneacetic acid and ellagic acid), one flavanol (catechin) and one dihydrochalcone flavonoid (phloretin). Quantitative results showed that rutin, myricetin, quercetin and kaempferol were the main flavonoids. Moreover, a variety of phenolic acid compounds were also detected in most of the berries from the Tibetan plateau. Among these compounds, the contents of protocatechuate and chlorogenic acid were high, and high levels of catechin and phloretin were also detected in these plateau berries.

Safflospermidines from the bee pollen of Helianthus annuus L. exhibit a higher in vitro antityrosinase activity than kojic acid

Background

Ozone deterioration in the atmosphere has become a severe problem causing overexposure of ultraviolet light, which results in humans in melanin overproduction and can lead to many diseases, such as skin cancer and melasma, as well as undesirable esthetic appearances, such as freckles and hyperpigmentation. Although many compounds inhibit melanin overproduction, some of them are cytotoxic, unstable, and can cause skin irritation. Thus, searching for new natural compounds with antityrosinase activity and less/no side effects is still required. Here, bee pollen derived from sunflower (Helianthus annuus L.) was evaluated.

Materials and methods

Sunflower bee pollen (SBP) was collected from Apis mellifera bees in Lopburi province, Thailand in 2017, extracted by methanol and sequentially partitioned with hexane and dichloromethane (DCM). The in vitro antityrosinase activity was evaluated using mushroom tyrosinase and the half maximal inhibitory concentration (IC₅₀) is reported. The antioxidation activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and reported as the half maximal effective concentration. Two pure compounds with antityrosinase activity were isolated by silica gel 60 column chromatography (SG₆₀CC) and high performance liquid chromatography (HPLC), and their chemical structure deduced by Nuclear Magnetic Resonance (NMR) analysis.

Results

The DCM partitioned extract of SBP (DCMSBP) had an antityrosinase activity (IC₅₀, 159.4 μg/mL) and was fractionated by SG₆₀CC, providing five fractions (DCMSBP1-5). The DCMSBP5 fraction was the most active (IC₅₀ = 18.8 μg/mL) and further fractionation by HPLC gave two active fractions, revealed by NMR analysis to be safflospermidine A and B. Interestingly, both safflospermidine A and B had a higher antityrosinase activity (IC₅₀ of 13.8 and 31.8 μM, respectively) than kojic acid (IC₅₀ of 44.0 μM). However, fraction DCMSBP5 had no significant antioxidation activity, while fractions DCMSBP1-4 showed a lower antioxidation activity than ascorbic acid.

Conclusion

Safflospermidine A and B are potential natural tyrosinase inhibitors.

Phloretin as both a substrate and inhibitor of tyrosinase: Inhibitory activity and mechanism

Tyrosinase is the rate-limiting enzyme for controlling the production of melanin in the human body, and overproduction of melanin can lead to a variety of skin disorders. In this paper, the inhibitory kinetics of phloretin on tyrosinase and their binding mechanism were determined using spectroscopy, molecular docking, antioxidant assays and chromatography. The spectroscopic results indicate that phloretin reversibly inhibits tyrosinase in a mix-type manner through a multiphase kinetic process with the IC₅₀ of 169.36 μmol/L. It is shown that phloretin has a strong ability to quench the intrinsic fluorescence of tyrosinase mainly through a static quenching procedure, suggesting that a stable phloretin-tyrosinase complex is generated. Molecular docking results suggest that the dominant conformation of phloretin binds to the gate of the active site of tyrosinase. Moreover, the antioxidant assays demonstrate that phloretin has powerful antioxidant capacity and has the ability to reduce o-dopaquinone to l-dopa just like ascorbic acid. Interestingly, the results of spectroscopy and chromatography indicate that phloretin is a substrate of tyrosinase but also an inhibitor. The possible inhibitory mechanism is proposed, which will be helpful to design and search for tyrosinase inhibitors.

Pistacia weinmannifolia ameliorates cigarette smoke and lipopolysaccharide‑induced pulmonary inflammation by inhibiting interleukin‑8 production and NF‑κB activation

Pistacia weinmannifolia (PW) has been used in traditional Chinese medicine to treat headaches, dysentery, enteritis and influenza. However, PW has not been known for treating respiratory inflammatory diseases, including chronic obstructive pulmonary disease (COPD). The present in vitro analysis confirmed that PW root extract (PWRE) exerts anti-inflammatory effects in phorbol myristate acetate- or tumor necrosis factor α (TNF-α)-stimulated human lung epithelial NCI-H292 cells by attenuating the expression of interleukin (IL)-8, IL-6 and Mucin A5 (MUC5AC), which are closely associated with the pulmonary inflammatory response in the pathogenesis of COPD. Thus, the aim of the present study was to evaluate the protective effect of PWRE on pulmonary inflammation induced by cigarette smoke (CS) and lipopoly-saccharide (LPS). Treatment with PWRE significantly reduced the quantity of neutrophils and the levels of inflammatory molecules and toxic molecules, including tumor TNF-α, IL-6, IL-8, monocyte chemoattractant protein-1, neutrophil elastase and reactive oxygen species, in the bronchoalveolar lavage fluid of mice with CS- and LPS-induced pulmonary inflammation. PWRE also attenuated the influx of inflammatory cells in the lung tissues. Furthermore, PWRE downregulated the activation of nuclear factor-κB and the expression of phosphodiesterase 4 in the lung tissues. Therefore, these findings suggest that PWRE may be a valuable adjuvant treatment for COPD.

Role of Apple Phytochemicals, Phloretin and Phloridzin, in Modulating Processes Related to Intestinal Inflammation

Plant-derived food consumption has gained attention as potential intervention for the improvement of intestinal inflammatory diseases. Apple consumption has been shown to be effective at ameliorating intestinal inflammation symptoms. These beneficial effects have been related to (poly)phenols, including phloretin (Phlor) and its glycoside named phloridzin (Phldz). To deepen the modulatory effects of these molecules we studied: i) their influence on the synthesis of proinflammatory molecules (PGE2, IL-8, IL-6, MCP-1, and ICAM-1) in IL-1β-treated myofibroblasts of the colon CCD-18Co cell line, and ii) the inhibitory potential of the formation of advanced glycation end products (AGEs). The results showed that Phlor (10-50 μM) decreased the synthesis of PGE2 and IL-8 and the formation of AGEs by different mechanisms. It is concluded that Phlor and Phldz, compounds found exclusively in apples, are positively associated with potential beneficial effects of apple consumption.

Fine-particulate matter aggravates cigarette smoke extract-induced airway inflammation via Wnt5a-ERK pathway in COPD

Background

Exposure to environmental particulate matter (PM) ≤2.5 μm in diameter (PM_2.5) and smoking are common contributors to COPD, and pertinent research implicates both factors in pulmonary inflammation. Using in vivo mouse and in vitro human cellular models, we investigated the joint impact of PM_2.5 pollution, and cigarette smoke (CS) in mice or cigarette-smoke extract (CSE) in cells on COPD inflammation, and explored potential mechanisms.

Methods

Tissue changes in lungs of C57BL/6 mice exposed to PM_2.5 and CS were studied by light microscopy, H&E, immunochemistry, and immunofluorescence-stained sections. Levels of inflammatory factors induced by PM_2.5/CS in mice and PM_2.5/CSE in 16HBE cells were also monitored by quantitative reverse-transcription (qRT)-PCR and ELISA. Expression of genes related to the Wnt5a-signaling pathway was assessed at transcriptional and protein levels using immunofluorescence, qRT-PCR, and Western blotting.

Results

Inflammatory response to combined exposure of PM_2.5 and CS or CSE in mouse and 16HBE cells surpassed responses incited separately. Although separate PM_2.5 and CS/CSE exposure upregulated the expression of Wnt5a (a member of the Wnt-secreted glycoprotein family), combined PM_2.5 and CS/CSE exposure produced a steeper rise in Wnt5a levels. Use of a Wnt5a antagonist (BOX5) successfully blocked related inflammatory effects. ERK phosphorylation appeared to mediate the effects of Wnt5a in the COPD model, promoting PM_2.5 aggravation of CS/CSE-induced airway inflammation.

Conclusion

Our findings suggest that combined PM_2.5 and CS/CSE exposure induce airway inflammation and Wnt5a expression in vivo in mice and in vitro in 16HBE cells. Furthermore, PM_2.5 seems to aggravate CS/CSE-induced inflammation via the Wnt5a–ERK pathway in the context of COPD.

Biochemical Basis of Anti-Cancer-Effects of Phloretin-A Natural Dihydrochalcone

Apple is a rich source of bioactive phytochemicals that help improve health by preventing and/or curing many disease processes, including cancer. One of the apple polyphenols is phloretin [2′,4′,6′-Trihydroxy-3-(4-hydroxyphenyl)-propiophenone], which has been widely investigated for its antioxidant, anti-inflammatory and anti-cancer activities in a wide array of preclinical studies. The efficacy of phloretin in suppressing xenograft tumor growth in athymic nude mice implanted with a variety of human cancer cells, and the ability of the compound to interfere with cancer cells signaling, have made it a promising candidate for anti-cancer drug development. Mechanistically, phloretin has been reported to arrest the growth of tumor cells by blocking cyclins and cyclin-dependent kinases and induce apoptosis by activating mitochondria-mediated cell death. The blockade of the glycolytic pathway via downregulation of GLUT2 mRNA and proteins, and the inhibition of tumor cells migration, also corroborates the anti-cancer effects of phloretin. This review sheds light on the molecular targets of phloretin as a potential anti-cancer and anti-inflammatory natural agent.

Rapid qualitative and quantitative analyses of eighteen phenolic compounds from Lycium ruthenicum Murray by UPLC-Q-Orbitrap MS and their antioxidant activity

Lycium ruthenicum Murray (LR) is a functional food, and it has long been used in traditional folk medicine. However, detailed qualitative and quantitative analyses related to its phenolic compounds remains scarce. This work reports, for the first time, the establishment of a rapid method for simultaneous identification and quantification of 25 phenolic compounds by UPLC-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS). This method was validated by LODs, LOQs, precision, repeatability, stability, mean recovery, recovery range and RSD. The confirmed method was applied to the analysis of phenolic compounds in LR. Finally, 18 phenolic compounds in LR were qualitatively and quantitatively analyzed. Among them, 11 constituents were detected for the first time, which included two flavonoids (catechin and naringenin) and seven phenolic acids (gallic acid, vanillic acid, 2,4-dihydroxybenzoic acid, veratronic acid, benzoic acid, ellagic acid and salicylic acid). Moreover, Phloretin and protocatechuate, belonging to the dihydrochalcone flavonoid and protocatechuic acid respectively, were also identified and quantified. The total phenolics content (20.17 ± 2.82 mg/g) and the total anthocyanin content (147.43 ± 1.81 mg/g) were determined. In addition, the antioxidant activities of the LR extract were evaluated through 2,2-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity, ferric reducing antioxidant power (FRAP) and total antioxidant activity (T-AOC) assays.