Baicalin is anti-inflammatory in cigarette smoke-induced inflammatory models in vivo and in vitro: A possible role for HDAC2 activity

Baicalin Protects Broilers against Avian Coronavirus Infection via Regulating Respiratory Tract Microbiota and Amino Acid Metabolism

An increasing amount of evidence indicates that Baicalin (Bai, a natural glycosyloxyflavone compound) exhibits an antiviral effect against avian viruses. However, it remains unclear if the antiviral effect of Bai against infectious bronchitis virus (IBV) is exerted indirectly by modulating respiratory tract microbiota and/or their metabolites. In this study, we investigated the protection efficacy of Bai in protecting cell cultures and broilers from IBV infection and assessed modulation of respiratory tract microbiota and metabolites during infection. Bai was administered orally to broilers by being mixed in with drinking water for seven days. Ultimately, broilers were challenged with live IBV. The results showed that Bai treatment reduced respiratory tract symptoms, improved weight gain, slowed histopathological damage, reduced virus loads and decreased pro-inflammation cytokines production. Western blot analysis demonstrated that Bai treatment significantly inhibited Toll-like receptor 7 (TLR7), myeloid differentiation factor 88 (MyD88) and nuclear factor kappa-B (NF-κB) expression both in cell culture and cells of the trachea. Bai treatment reversed respiratory tract microbiota dysbiosis, as shown by 16S rDNA sequencing in the group of broilers inoculated with IBV. Indeed, we observed a decrease in Proteobacteria abundance and an increase in Firmicutes abundance. Metabolomics results suggest that the pentose phosphate pathway, amino acid and nicotinamide metabolism are linked to the protection conferred by Bai against IBV infection. In conclusion, these results indicated that further assessment of anti-IBV strategies based on Bai would likely result in the development of antiviral molecule(s) which can be administered by being mixed with feed or water.

Hippocampus protection from apoptosis by Baicalin in a LiCl-pilocarpine-induced rat status epilepticus model through autophagy activation

BACKGROUND

Autophagy is associated with hippocampal injury following status epilepticus (SE) and is considered a potential therapeutic mechanism. Baicalin, an emerging multitherapeutic drug, has shown neuroprotective effects in patients with nervous system diseases due to its antioxidant properties.

AIM

To investigate the potential role of autophagy in LiCl-pilocarpine-induced SE.

METHODS

The drugs were administered 30 min before SE. Nissl staining showed that Baicalin attenuated hippocampal injury and reduced neuronal death in the hippocampus. Western blotting and terminal deoxynucleotidyl transferase dUTP nick end labeling assay confirmed that Baicalin reversed the expression intensity of cleaved caspase-3 and apoptosis in hippocampal CA1 following SE. Fur-thermore, western blotting and immunofluorescence staining were used to measure the expression of autophagy markers (p62/SQSTM1, Beclin 1, and LC3) and apoptotic pathway markers (cleaved caspase-3 and Bcl-2).

RESULTS

Baicalin significantly upregulated autophagic activity and downregulated mitochondrial apoptotic pathway markers. Conversely, 3-methyladenine, a commonly used autophagy inhibitor, was simultaneously administered to inhibit the Baicalin-induced autophagy, abrogating the protective effect of Baicalin on the mitochondrial apoptotic level.

CONCLUSION

We illustrated that Baicalin-induced activation of autophagy alleviates apoptotic death and protects the hippocampus of SE rats.

Pharmacological effects of baicalin in lung diseases

The flavonoids baicalin and baicalein were discovered in the root of Scutellaria baicalensis Georgi and are primarily used in traditional Chinese medicine, herbal supplements and healthcare. Recently, accumulated investigations have demonstrated the therapeutic benefits of baicalin in treating various lung diseases due to its antioxidant, anti-inflammatory, immunomodulatory, antiapoptotic, anticancer, and antiviral effects. In this review, the PubMed database and ClinicalTrials website were searched with the search string "baicalin" and "lung" for articles published between September 1970 and March 2023. We summarized the therapeutic role that baicalin plays in a variety of lung diseases, such as chronic obstructive pulmonary disease, asthma, pulmonary fibrosis, pulmonary hypertension, pulmonary infections, acute lung injury/acute respiratory distress syndrome, and lung cancer. We also discussed the underlying mechanisms of baicalin targeting in these lung diseases.

Baicalin inhibits oxidative injures of mouse uterine tissue induced by acute heat stress through activating the Keap1/Nrf2 signaling pathway

Heat stress effect the physiological functions of body, and reproductive system is one of the most sensitive. It's imperative to find out suitable measures to alleviate harmful effects of heat stress. Baicalin is well-known with its antioxidative property. To examine whether Baicalin could reduce oxidative injures of uterine tissue in heat-stressed mice. The mice were divided into four groups: control (Con), Baicalin (Bai), heat stress (H) and heat stress plus Baicalin (H + Bai). The oxidative damage of uterine tissue was detected by ELISA, H&E staining, tunnel assay and immunohistochemical staining. The protein/mRNA expressions of Keap1/Nrf2 related factors were detected by Western blot or QPCR. The results showed that mice heat-stressed at 41 °C for 2 h induced macroscopic changes, significantly increased MDA content and reduced activities of antioxidant enzymes including SOD, CAT and GSH-Px of the uterine tissue. Compared with Con group, heat stress up-regulated caspase-3 and caspase-9, enhanced the apoptosis of endometrial epithelial and glandular epithelial cells, improved the HO-1 mRNA/protein and NQO1 protein expressions, while down-regulated the mRNA/protein of Keap1. Compared with H group, antioxidant enzyme activities, Nrf2 protein and Nrf2, NQO1 and GCLC mRNA expressions were significantly increased in the H + Bai group. While the uterine epithelial cells apoptosis, MDA contents, caspase-3, caspase-9 and Keap1 protein and HO-1 mRNA expressions were decreased in the H + Bai group of mice compared with that in H group. Briefly, acute heat stress causes oxidative injures and apoptosis of mouse uterine tissue and Baicalin protects uterine tissue from the damages possibly through Keap1/Nrf2 signaling pathway.

Antibacterial and Anti-Inflammatory Potential of Chinese Medicinal Herbs: Lonicerae flos, Lonicerae japonicae flos, Scutellaria baicalensis Georgi, and Forsythia suspensa

Chinese herbal medicine (CHM) represents a potent, safe, and efficacious reservoir of treatment options against an array of microbial infections and inflammatory diseases. It has a long history of positive clinical outcomes with minimal or no side effects while enhancing and bolstering the host's protection against infections. With its unique ability to prevent, treat, and manage a wide range of diseased conditions, CHM has been successfully practiced in China for thousands of years. In the modern medical era, where harsh therapeutic drugs and antimicrobial resistance (AMR) present a significant challenge, CHM warrants further exploration. The present review highlights and focuses on 4 major CHM-based herbs, that is, ( Lonicerae flos [ LF] , Lonicerae japonicae flos [ LJF] , Scutellaria baicalensis Georgi [ SBG] , and Forsythia suspensa [ FS]) in terms of their antibacterial and anti-inflammatory efficacies. A detailed literature survey was done by the team using a systematic electronic search from PubMed, Science Direct, Google Scholar, Research Gate, books, etc. This was followed by data collecting, pertinent data extraction, in-depth analysis, and composing the final review. Each herb has been discussed in detail describing its mechanism adopted and the bioactive components involved in alleviating bacterial infections and inflammatory damage. Further, proof of efficacy by detailing the major past studies and major findings has been discussed for each of the 4 herbs. This review will give the scientific community the opportunity to update their knowledge on the subject, which is crucial for heralding the process of bringing CHM-based medicines closer to clinical development given the area of alternative medicine's rapid advancements.

Exploring the protective mechanism of baicalin in treatment of atherosclerosis using endothelial cells deregulation model and network pharmacology

Background

Baicalin is a generally available flavonoid with potent biological activity. The present study aimed to assess the underlying mechanism of baicalin in treatment of atherosclerosis (AS) with the help of network pharmacology, molecular docking and experimental validation.

Methods

The target genes of baicalin and AS were identified from public databases, and the overlapping results were considered to be baicalin-AS targets. Core target genes of baicalin were obtained through the PPI network and validated by a clinical microarray dataset (GSE132651). Human aortic endothelial cells (HAECs) were treated with Lipopolysaccharide (LPS) to construct an endothelial injury model. The expression of NOX4 was examined by real-time qPCR and western blot. Flow cytometry was used to detect intracellular levels of reactive oxygen species (ROS). Furthermore, HAECs were transfected with NOX4-specific siRNA and then co-stimulated with baicalin and LPS to investigate whether NOX4 was involved in the anti-oxidative stress effects of baicalin.

Results

In this study, baicalin had 45 biological targets against AS. Functional enrichment analysis demonstrated that most targets were involved in oxidative stress. Using the CytoHubba plug-in, we obtained the top 10 genes in the PPI network ranked by the EPC algorithm. Molecular docking and microarray dataset validation indicated that NOX4 may be an essential target of baicalin, and its expression was significantly suppressed in AS samples compared to controls. In endothelial injury model, intervention of HAECs with baicalin increased the expression levels of NOX4 and NOS3 (eNOS), and decreased LPS-induced ROS generation. After inhibition of NOX4, the anti-ROS-generating effect of baicalin was abolished.

Conclusion

Collectively, we combined network pharmacology and endothelial injury models to investigate the anti-AS mechanism of baicalin. The results demonstrate that baicalin may exert anti-oxidative stress effects by targeting NOX4, providing new mechanisms and insights to baicalin for the treatment of AS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03738-3.

Baicalin Inhibits Inflammation in Rats with Chronic Obstructive Pulmonary Disease by the TLR2/MYD88/NF-κBp65 Signaling Pathway

Objective

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease with a relatively high morbidity and death rate. This study aimed to investigate the inhibitory effect of baicalin (BA) on inflammation in COPD rats and its possible mechanism.

Methods

The experimental COPD of SD rats were induced by LPS, smoking, and cold stimulation, and they were randomly divided into the control group, COPD group, COPD + LB group, COPD + MB group, and COPD + HB group. The test of pulmonary function and the HE staining were carried out in COPD rats. The levels of TNF-α, IL-1β, IL-6, IL-10, and IL-8, as well as GSH, SOD, and MDA in serum, were detected by ELISA. The levels of TLR2, MYD88, TNF-α, and IL-1β mRNA in BALF were detected by qPCR. The expression of TLR2/MYD88/NF-κBp65 pathway-related proteins was also detected by the Western blot and immunohistochemistry assays.

Results

Compared to the COPD model group, BA treatment significantly improved the pulmonary function and pathologic changes, reduced the levels of TNF-α, IL-1β, IL-6, IL-10, IL-8, and MDA, and increased the levels of IL-10, SOD, and GSH in COPD rats. In addition, BA could also decrease the protein levels of MYD88, p–NF–κBp65/NF-κBp65, TLR2, and TLR4 but increase the protein level of p-IκBa/IκB in lung tissue of COPD rats.

Conclusion

BA ameliorated inflammatory response and oxidative stress in COPD rats by regulating the TLR2/MYD88/NF-κBp65 signaling pathway.

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

Scutellaria baicalensis and its constituents baicalin and baicalein as antidotes or protective agents against chemical toxicities: a comprehensive review

Scutellaria baicalensis (SB), also known as the Chinese skullcap, has a long history of being used in Chinese medicine to treat a variety of conditions ranging from microbial infections to metabolic syndrome and malignancies. Numerous studies have reported that treatment with total SB extract or two main flavonoids found in its root and leaves, baicalin (BA) and baicalein (BE), can prevent or alleviate the detrimental toxic effects of exposure to various chemical compounds. It has been shown that BA and BE are generally behind the protective effects of SB against toxicants. This paper aimed to review the protective and therapeutic effects of SB and its main components BA and BE against chemical compounds that can cause intoxication after acute or chronic exposure and seriously affect different vital organs including the brain, heart, liver, and kidneys. In this review paper, we had a look into a total of 221 in vitro and in vivo studies from 1995 to 2021 from the scientific databases PubMed, Scopus, and Web of Science which reported protective or therapeutic effects of BA, BE, or SB against drugs and chemicals that one might be exposed to on a professional or accidental basis and compounds that are primarily used to simulate disease models. In conclusion, the protective effects of SB and its flavonoids can be mainly attributed to increase in antioxidants enzymes, inhibition of lipid peroxidation, reduction of inflammatory cytokines, and suppression of apoptosis pathway.

Unravelling the Therapeutic Potential of Botanicals Against Chronic Obstructive Pulmonary Disease (COPD): Molecular Insights and Future Perspectives

Background: COPD (chronic obstructive pulmonary disease) is a serious health problem worldwide. Present treatments are insufficient and have severe side effects. There is a critical shortage of possible alternative treatments. Medicinal herbs are the most traditional and widely used therapy for treating a wide range of human illnesses around the world. In several countries, different plants are used to treat COPD. Purpose: In this review, we have discussed several known cellular and molecular components implicated in COPD and how plant-derived chemicals might modulate them. Methods: We have discussed how COVID-19 is associated with COPD mortality and severity along with the phytochemical roles of a few plants in the treatment of COPD. In addition, two tables have been included; the first summarizes different plants used for the treatment of COPD, and the second table consists of different kinds of phytochemicals extracted from plants, which are used to inhibit inflammation in the lungs. Conclusion: Various plants have been found to have medicinal properties against COPD. Many plant extracts and components may be used as novel disease-modifying drugs for lung inflammatory diseases.

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.

Targeting phytoprotection in the COVID-19-induced lung damage and associated systemic effects-the evidence-based 3PM proposition to mitigate individual risks

The risks related to the COVID-19 are multi-faceted including but by far not restricted to the following: direct health risks by poorly understood effects of COVID-19 infection, overloaded capacities of healthcare units, restricted and slowed down care of patients with non-communicable disorders such as cancer, neurologic and cardiovascular pathologies, among others; social risks-restricted and broken social contacts, isolation, professional disruption, explosion of aggression in the society, violence in the familial environment; mental risks-loneliness, helplessness, defenceless, depressions; and economic risks-slowed down industrial productivity, broken delivery chains, unemployment, bankrupted SMEs, inflation, decreased capacity of the state to perform socially important programs and to support socio-economically weak subgroups in the population. Directly or indirectly, the above listed risks will get reflected in a healthcare occupation and workload which is a tremendous long-term challenge for the healthcare capacity and robustness. The article does not pretend to provide solutions for all kind of health risks. However, it aims to present the scientific evidence of great clinical utility for primary, secondary, and tertiary care to protect affected individuals in a cost-effective manner. To this end, due to pronounced antimicrobial, antioxidant, anti-inflammatory, and antiviral properties, naturally occurring plant substances are capable to protect affected individuals against COVID-19-associated life-threatening complications such as lung damage. Furthermore, they can be highly effective, if being applied to secondary and tertiary care of noncommunicable diseases under pandemic condition. Thus, the stratification of patients evaluating specific health conditions such as sleep quality, periodontitis, smoking, chronic inflammation and diseases, metabolic disorders and obesity, vascular dysfunction, and cancers would enable effective managemenet of COVID-19-associated complications in primary, secondary, and tertiary care in the context of predictive, preventive, and personalized medicine (3PM).

Baicalin ameliorates cigarette smoke-induced airway inflammation in rats by modulating HDAC2/NF-κB/PAI-1 signalling

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease distinguished by airway remodelling and progressive inflammation. PAI-1 is an important regulator of fibrosis. Recent studies have shown that PAI-1 seems to be involved in COPD progression. Elevated levels of PAI-1 have been found in the lungs of patients with acute inflammation. PAI-1 has been shown to regulate the levels of proinflammatory cytokines in the lungs, such as tumour necrosis factor (TNF)-α and interleukin (IL)-6, indicating that PAI-1 may play a fundamental role during inflammation. In the present study, we investigated the anti-inflammatory role of baicalin, the main active component of Scutellaria baicalensis, against cigarette smoke (extract) (CS/CSE)-induced airway inflammation in vivo and in vitro. For the in vivo study, SD rats were exposed to CS for 1 h/day, 6 days/week, for 24 weeks and treated with baicalin (40, 80 and 160 mg/kg) or budesonide (0.2 mg/kg). For this study, HBE cells were pretreated with baicalin (10, 20, 40 μM) or dexamethasone (10^-7 M) and then exposed to CSE. We found that baicalin treatment could ameliorate CS-induced airway inflammatory infiltration in rats and decrease PAI-1 expression. The ELISA results showed that baicalin significantly inhibited the levels of TNF-α and IL-1β in CS/CSE-exposed rats and cells. Mechanistic studies showed that baicalin enhanced histone deacetylase 2 (HDAC2) protein expression and inhibited the expression of NF-κB and its downstream target PAI-1, and these effects were reversed by the HDAC2 inhibitor CAY-10683. In conclusion, baicalin ameliorated CS-induced airway inflammation in rats, and these effects were partially attributed to the modulation of HDAC2/NF-κB/PAI-1 signalling.

Baicalin alleviates chronic obstructive pulmonary disease through regulation of HSP72-mediated JNK pathway

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by airway obstruction and progressive lung inflammation. As the primary ingredient of a traditional Chinese medical herb, Baicalin has been previously shown to possess anti-inflammatory abilities. Thus, the current study aimed to elucidate the mechanism by which baicalin alleviates COPD.

METHODS

Baicalin was adopted to treat cigarette smoke in extract-exposed MLE-12 cells after which cell viability and apoptosis were determined. The production of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), IL-8 were determined by enzyme-linked immunoassay. A COPD mouse model was constructed via exposure to cigarette smoke and lipopolysaccharide, baicalin treatment. Lung function and inflammatory cell infiltration were determined and the production of Muc5AC, TNF-α, IL-6, IL-8 in the bronchoalveolar lavage fluid (BALF) was assayed by ELISA. The effect of HSP72 and JNK on COPD following treatment with baicalin was assessed both in vivo and in vitro by conducting loss- and gain- function experiments.

RESULTS

Baicalin improved lung function evidenced by reduction in inflammatory cell infiltration and Muc5AC, TNF-α, IL-6 and IL-8 levels observed in BALF in mice. Baicalin was further observed to elevate cell viability while inhibited apoptosis and TNF-α, IL-6 and IL-8 levels in MLE-12 cells. Baicalin treatment increased HSP72 expression, while its depletion reversed the effect of baicalin on COPD. HSP72 inhibited the activation of JNK, while JNK activation was found to inhibit the effect of baicalin on COPD.

CONCLUSIONS

Baicalin upregulated the expression of HSP72, resulting in the inhibition of JNK signaling activation, which ultimately alleviates COPD.

Treatment of chronic airway diseases using nutraceuticals: Mechanistic insight

Respiratory diseases, both acute and chronic, are reported to be the leading cause of morbidity and mortality, affecting millions of people globally, leading to high socio-economic burden for the society in the recent decades. Chronic inflammation and decline in lung function are the common symptoms of respiratory diseases. The current treatment strategies revolve around using appropriate anti-inflammatory agents and bronchodilators. A range of anti-inflammatory agents and bronchodilators are currently available in the market; however, the usage of such medications is limited due to the potential for various adverse effects. To cope with this issue, researchers have been exploring various novel, alternative therapeutic strategies that are safe and effective to treat respiratory diseases. Several studies have been reported on the possible links between food and food-derived products in combating various chronic inflammatory diseases. Nutraceuticals are examples of such food-derived products which are gaining much interest in terms of its usage for the well-being and better human health. As a consequence, intensive research is currently aimed at identifying novel nutraceuticals, and there is an emerging notion that nutraceuticals can have a positive impact in various respiratory diseases. In this review, we discuss the efficacy of nutraceuticals in altering the various cellular and molecular mechanisms involved in mitigating the symptoms of respiratory diseases.

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.

Natural product derived phytochemicals in managing acute lung injury by multiple mechanisms

Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS) as common life-threatening lung diseases with high mortality rates are mostly associated with acute and severe inflammation in lungs. With increasing in-depth studies of ALI/ARDS, significant breakthroughs have been made, however, there are still no effective pharmacological therapies for treatment of ALI/ARDS. Especially, the novel coronavirus pneumonia (COVID-19) is ravaging the globe, and causes severe respiratory distress syndrome. Therefore, developing new drugs for therapy of ALI/ARDS is in great demand, which might also be helpful for treatment of COVID-19. Natural compounds have always inspired drug development, and numerous natural products have shown potential therapeutic effects on ALI/ARDS. Therefore, this review focuses on the potential therapeutic effects of natural compounds on ALI and the underlying mechanisms. Overall, the review discusses 159 compounds and summarizes more than 400 references to present the protective effects of natural compounds against ALI and the underlying mechanism.

Pharmacological and computer-aided studies provide new insights into Millettia peguensis Ali (Fabaceae)

Millettia peguensis, popular for its ethnopharmacological uses, was employed to evaluate its different pharmacological properties in this study. The analgesic studies of the plant have been performed by acetic acid-induced writhing and formalin-induced licking tests respectively, whereas the antidiarrheal experiment was done by castor oil-induced diarrheal test. Besides, antioxidant, cytotoxic, antimicrobial, thrombolytic evaluations were performed by DPPH scavenging with phenol content determination, brine shrimp lethality, disc diffusion and clot lysis methods respectively. Moreover, in silico study of the phytoconstituents was carried out by molecular docking and ADME/T analysis.

The methanol extract of Millettia peguensis (MEMP) revealed significant biological activity in the analgesic and antidiarrheal test (p < 0.001) compared to the standards. Antioxidant assay displayed promising IC₅₀ values (15.96 μg/mL) with the total phenol content (65.27 ± 1.24 mg GAE/g). In the cytotoxicity study, the LC₅₀ value was found to be 1.094 μg/mL. Besides, MEMP was highly sensitive to the bacteria but less liable to clot lysis. Furthermore, phytoconstituents exposed potential binding affinity towards the selected receptors, whereas the ADME/T properties indicated the drug likeliness of the plant. The outcomes of these findings suggest the therapeutic potential of this plant against pain, diarrhea, inflammation, and tissue toxicity.

Comparative effectiveness of six Chinese herb formulas for acute exacerbation of chronic obstructive pulmonary disease: a systematic review and network meta-analysis

Background

Six Chinese herb formulas, namely, the Weijing decoction (WJ), the Maxingshigan decoction (MXSG), the Yuebijiabanxia decoction (YBBX), the Qingqihuatan decoction (QQHT), the Dingchuan decoction (DC) and the Sangbaipi decoction (SBP), are commonly used, along with routine pharmacotherapy, to manage the acute exacerbation of chronic obstructive pulmonary disease (AECOPD). In this study, we conducted a systematic review to summarize the efficacy of these six formulas, and we also conducted a network meta-analysis (NMA) to rank these formulas.

Methods

We searched five English databases and four Chinese databases, with dates ranging from the starting dates of these databases to December 2016. Randomized controlled trials that evaluated any of the six Chinese herb formulas combined with the use of pharmacotherapy for AECOPD were identified.

Results

Fifty-five studies involving 4560 participants were included. The pairwise meta-analyses showed that WJ and QQHT had superior effects on the improvement of lung function (forced expiratory volume in 1 seconds; FEV1) (mean difference (MD): 0.25, 95% confidence interval (CI): 0.19–0.30 and 0.34, 95%CI: 0.10–0.58). MXSG, WJ and QQHT were found to be more effective for improving arterial blood gases (PaO2 and PaCO2). In terms of effective rates, all of these formulas had additional favourable effects compared to routine pharmacotherapy. The results of the NMA analyses indicated that only MXSG showed superior add-on effects for the improvement of FEV1 (MD: 0.37, 95% credible interval (CrI): 0.03–0.72). Most of the formulas combined with routine pharmacotherapy were superior to pharmacotherapy alone for the improvement of arterial blood gases and effective rates. The ranking tests suggested that QQHT and MXSG combined with routine pharmacotherapy might be optimal options for the treatment of AECOPD.

Conclusions

This NMA indicated that QQHT and MXSG might be more effective treatment regimens for AECOPD. Further well-designed studies that specifically examine the direct comparisons of these formulas are needed to support our conclusions.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2633-2) contains supplementary material, which is available to authorized users.

Effects of Scutellaria baicalensis Extract on Cigarette Smoke-Induced Airway Inflammation in a Murine Model of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD), including pulmonary emphysema and chronic bronchitis as well as structural and inflammatory changes in small airways, is insensitive to corticosteroid therapies. This study aimed to evaluate the effects of Scutellaria baicalensis root extract (SB_E) in a mouse model of COPD. The COPD mouse model was produced by challenging C57BL/6 mice with a cigarette smoke extract and lipopolysaccharide (LPS). SB_E significantly decreased the neutrophil counts in blood and bronchoalveolar lavage fluid (BALF), and the production of tumor necrosis factor (TNF)-α, interleukin (IL)-17A, macrophage inflammatory protein 2 (MIP2), and chemokine (C-X-C motif) ligand 1 (CXCL-1) in BALF, and TNF-α mRNA expression in lung tissue. The histological lung injury was also alleviated by treatment with SB_E. Thus, SB_E effectively inhibited airway inflammation by regulating the expression of inflammatory cytokines by blocking MIP2 and CXCL-1 secretion. Therefore, S. baicalensis may be a potential therapeutic agent for COPD.

Metabolic profiling of endogenous bile acids: a novel method to assess hepatoprotective effect of Tanreqing capsule on carbon-tetrachloride-induced liver injury in rats

Tanreqing (TRQ), a traditional Chinese medicine (TCM) formula, can alleviate liver injury and improve liver function. Its pharmacological mechanisms of actions are still unclear due to its complex components and multi-target natures. Metabolomic study is an effective approach to investigating drug pharmacological actions, new diagnostic markers, and potential mechanisms of actions. In the present study, a new strategy was used to evaluate the protective effect of TRQ capsule against carbon tetrachloride (CCl₄)-induced hepatotoxicity in rats, by analyzing metabolic profiling of endogenous bile acids (BAs) along with biochemical and histological analyses. BAs concentrations were determined by ultra-performance liquid chromatography coupled with quadrupole mass spectrometry (UPLC-MS). Principal component analysis and partial least squares discriminant analysis were then employed to analyze the UPLC-MS results and compare the hepatoprotective effect of TRQ capsule in different groups at the doses of 0.36, 1.44, and 2.88 g·kg^-1 body weight, respectively. Moreover, our results suggested that taurocholic acid (TCA) and taurohyodesoxycholic acid (THDCA) were the most important biochemical markers, which were indicative of CCl₄-induced acute hepatic damage and hepatoprotective effect of TRQ capsule. Therefore, this new strategy would be an excellent alternative method for evaluating hepatoprotective effect and proposing potential mechanisms of action for other drugs as well.

Baicalin Exerts Anti-Airway Inflammation and Anti-Remodelling Effects in Severe Stage Rat Model of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a worldwide epidemic. Current approaches are disappointing due to limited improvement of the disease development. The present study established 36-week side stream cigarette smoke induced rat model of COPD with advanced stage feature and evaluted the effects of baicalin on the model. Fifty-four Sprague–Dawley rats were randomly divided into six groups including room air control, cigarette smoke exposure, baicalin (40 mg/kg, 80 mg/kg, and 160 mg/kg), and budesonide used as a positive control. Rats were exposed to cigarette smoke from 3R4F research cigarettes. Pulmonary function was evaluated and pathological changes were also observed. Cytokine level related to airway inflammation and remodelling in blood serum, bronchoalveolar lavage fluid, and lung tissue was determined. Blood gases and HPA axis function were also examined, and antioxidant levels were quantified. Results showed that, after treatment with baicalin, lung function was improved and histopathological changes were ameliorated. Baicalin also regulated proinflammatory and anti-inflammatory balance and also airway remodelling and anti-airway remodelling factors in blood serum, bronchoalveolar lavage fluid, and lung tissue. Antioxidant capacity was also increased after treatment with baicalin in COPD rat model. HPA axis function was improved in baicalin treated groups as compared to model group. Therefore, baicalin exerts lung function protection, proinflammatory and anti-inflammatory cytokine regulation, anti-airway remodelling, and antioxidant role in long term CS induced COPD model.

Baicalin attenuates lipopolysaccharide-induced pro-inflammatory cytokine expression in murine macrophage cell line RAW264.7 through miR-124-STAT3 axis

Baicalin, a flavonoid isolated from Scutellaria baicalensis Georgi, has shown a wide range of anti-inflammatory, antioxidative, antiviral, and antitumor properties. However, the molecular mechanism of how baicalin exerts its effects, especially on inflammation regulation, has not been fully investigated. In this article, we report the effects of baicalin on the mouse macrophage cell line RAW264.7. Our results demonstrate that baicalin inhibits the production of inflammatory factors interleukin-6 and tumor necrosis factor-alpha upon lipopolysaccharide stimulation of macrophages. We observed that baicalin inhibits STAT3 activation through retarding its expression and phosphorylation. Interestingly, baicalin treatment promotes the elevation of miR-124 in lipopolysaccharide-treated macrophages. Overexpression of the miR-124 mimic in RAW264.7 reduced STAT3 expression and phosphorylation. Furthermore, inhibition of miR-124 attenuated the dysregulation of STAT3 and reduction of inflammatory factors upon baicalin treatment. Our results revealed the molecular mechanism that baicalin attenuates pro-inflammatory cytokine production through miR-124-STAT3 signaling pathway, suggesting that miR-124 is an important modulator in regulating anti-inflammation by baicalin in macrophages.

Food Bioactive HDAC Inhibitors in the Epigenetic Regulation of Heart Failure

Approximately 5.7 million U.S. adults have been diagnosed with heart failure (HF). More concerning is that one in nine U.S. deaths included HF as a contributing cause. Current HF drugs (e.g., β-blockers, ACEi) target intracellular signaling cascades downstream of cell surface receptors to prevent cardiac pump dysfunction. However, these drugs fail to target other redundant intracellular signaling pathways and, therefore, limit drug efficacy. As such, it has been postulated that compounds designed to target shared downstream mediators of these signaling pathways would be more efficacious for the treatment of HF. Histone deacetylation has been linked as a key pathogenetic element for the development of HF. Lysine residues undergo diverse and reversible post-translational modifications that include acetylation and have historically been studied as epigenetic modifiers of histone tails within chromatin that provide an important mechanism for regulating gene expression. Of recent, bioactive compounds within our diet have been linked to the regulation of gene expression, in part, through regulation of the epi-genome. It has been reported that food bioactives regulate histone acetylation via direct regulation of writer (histone acetyl transferases, HATs) and eraser (histone deacetylases, HDACs) proteins. Therefore, bioactive food compounds offer unique therapeutic strategies as epigenetic modifiers of heart failure. This review will highlight food bio-actives as modifiers of histone deacetylase activity in the heart.

Scutellaria baicalensis Attenuates Airway Remodeling via PI3K/Akt/NF-κB Pathway in Cigarette Smoke Mediated-COPD Rats Model

Background. Scutellaria baicalensis (SB) is commonly used in traditional Chinese medicine for chronic inflammatory diseases. This study aims to investigate the effects of the early intervention with SB on airway remodeling in a well-established rat model of COPD induced by cigarette smoking. Methods. COPD model in Sprague Dawley (SD) rats were established by exposing them to smoke for 6 days/week, for 12 weeks, 24 weeks, or 36 weeks. Meanwhile, rats were randomly divided into normal control group, model group, Budesonide (BUD) group, and the SB (low, middle, and high) dose groups with 8 rats in each group and 3 stages (12 weeks, 24 weeks, and 36 weeks). After treatment, the pulmonary function was evaluated by BUXCO system and the morphology changes of the lungs were observed with HE and Masson staining. The serum IL-6, IL-8, and IL-10 and TNF-α, TGF-beta (TGF-β1), MMP-2, MMP-9, and TIMP-1 levels in BALF were detected by ELISA-kit assay. The protein expression levels of AKT and NF-κB (p65) were determined by western blot (WB). Results. The oral of SB significantly improved pulmonary function (PF) and ameliorated the pathological damage and attenuated inflammatory cytokines infiltration into the lungs. Meanwhile, the levels of TGF-β, MMP-2, MMP-9, and TIMP-1 were partially significantly decreased. The levels of PI3K/AKT/NF-κB pathway were also markedly suppressed by SB. Conclusions. SB could significantly improve the condition of airway remodeling by inhibiting airway inflammation and partially quenching TGF-β and MMPs via PI3K/AKT/NF-κB pathway.

Baicalin Alleviates Lipopolysaccharide-Induced Liver Inflammation in Chicken by Suppressing TLR4-Mediated NF-κB Pathway

As a kind of potent stimulus, lipopolysaccharide (LPS) has the ability to cause cell damage by activating toll-like receptor(TLR)4, then nuclear factor kappa B (NF-κB) translocates into the nucleus and changes the expression of related inflammatory genes. Baicalin is extracted from Radix Scutellariae, which possesses anti-inflammation, antioxidant and antibacterial properties. However, the effects of it on LPS-induced liver inflammation have not been fully elucidated. This study aims to investigate the anti-inflammatory effects of Baicalin on the LPS-induced liver inflammation and its underlying molecular mechanisms in chicken. The results of histopathological changes, serum biochemical analysis, NO levels and myeloperoxidase activity showed that Baicalin pretreatment ameliorated LPS-induced liver inflammation. ELISA and qPCR assays showed that Baicalin dose-dependently suppressed the production of IL-1β, IL-6, and TNF-α. Furthermore, the mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were significantly decreased by Baicalin. TLR4 is an important sensor in LPS infection. Molecular studies showed that the expression of TLR4 was inhibited by Baicalin pretreatment. In addition, Baicalin pretreatment inhibited NF-kB signaling pathway activation. All results demonstrated the protective effects of Baicalin pretreatment against LPS-induced liver inflammation in chicken via negative regulation of inflammatory mediators through the down-regulation of TLR4 expression and the inhibition of NF-kB activation.

Therapeutic Potential of Medicinal Plants and Their Constituents on Lung Inflammatory Disorders

Acute bronchitis and chronic obstructive pulmonary diseases (COPD) are essentially lung inflammatory disorders. Various plant extracts and their constituents showed therapeutic effects on several animal models of lung inflammation. These include coumarins, flavonoids, phenolics, iridoids, monoterpenes, diterpenes and triterpenoids. Some of them exerted inhibitory action mainly by inhibiting the mitogen-activated protein kinase pathway and nuclear transcription factor-κB activation. Especially, many flavonoid derivatives distinctly showed effectiveness on lung inflammation. In this review, the experimental data for plant extracts and their constituents showing therapeutic effectiveness on animal models of lung inflammation are summarized.

Effects of Astragalus and Codonopsis pilosula polysaccharides on alveolar macrophage phagocytosis and inflammation in chronic obstructive pulmonary disease mice exposed to PM2.5

Astragalus and Codonopsis pilosula are used for their immunomodulatory and anti-inflammatory effects. Here, we investigated the effects of Astragalus polysaccharides (APS) and Codonopsis pilosula polysaccharides (CPP) on alveolar macrophage (AM) phagocytosis and inflammation in chronic obstructive pulmonary disease (COPD) associated with exposure to particulate matter with a mean aerodynamic diameter ≤2.5μm (PM2.5). A mouse model of COPD was established by cigarette smoke exposure. PM2.5 exposure was performed by inhalation of a PM2.5 solution aerosol. APS and CPP were administered intragastrically. COPD showed defective AM phagocytosis and increased levels of interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α in bronchoalveolar lavage fluid and serum. PM2.5 exposure aggravated the damage, and this effect was reversed by APS and CPP gavage. The results indicate that APS and CPP may promote defective AM phagocytosis and ameliorate the inflammatory response in COPD with or without PM2.5 exposure.

Baicalin promoted site-2 protease and not site-1 protease in endoplasmic reticulum stress-induced apoptosis of human hepatocellular carcinoma cells

Baicalin (5,6-dihydroxy-7-o-glucuronide flavone) is an extract from the roots of Chinese herb Huang Qin (Scutellaria baicalensis Georgi) and is reported to have antioxidative, antiproliferative, anti-inflammatory, and anticancer activities. This study aimed to investigate the inhibitory effect of baicalin on human hepatocellular carcinoma (HCC) cells and the involvement of endoplasmic reticulum stress-induced cell apoptosis. Two human HCC cell lines, HepG2 and SMMC7221, were used in this study. The cells were incubated with baicalin solutions at various concentrations. A 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess cell proliferation inhibition; a TUNEL assay was used to evaluate cell apoptosis; small RNA interference was applied to silence IRE1, ATF6, and protein kinase R-like ER kinase (PERK), which are transmembrane proteins inducing cell apoptosis, and two proteases (S1P and S2P) which cleave ATF6. Real-time PCR was used to evaluate the silencing effects of specific siRNA. Expression levels of specific proteins were analyzed by western blotting. Baicalin was found to inhibit the proliferation of HCC cells by inducing apoptosis in a concentration-dependent manner. Elevated expression levels of GRP78, CHOP, p50-ATF6, and caspase12 were found after baicalin incubation. Compared with IRE1 and PERK silencing, ATF6 knockdown dramatically impaired baicalin's apoptosis-inducing activity. Furthermore, S2P silencing, rather than S1P silencing, was also found to impair baicalin-induced HCC cell apoptosis significantly. In conclusion, (a) baicalin inhibits human HCC cells by inducing apoptosis; (b) baicalin induces cell apoptosis by activating ATF6 signaling pathway in endoplasmic reticulum (ER) stress;

Baicalin attenuates lipopolysaccharide induced inflammation and apoptosis of cow mammary epithelial cells by regulating NF-κB and HSP72

Baicalin is the main ingredient of traditional Chinese herbal medicine, Scutellaria baicalensis, which has been widely used clinically as an anti-inflammatory agent. However, molecular mechanism of action of this drug is not yet clear. In the present study, the protective mechanism of baicalin against lipopolysaccharide (LPS) induced inflammatory injury in cow mammary epithelial cells (CMECs) was explored. For this purpose, in vitro cultured CMECs were treated with baicalin (10μg/mL) and LPS (10μg/mL) for 24 and 12h, respectively, and the cell viability was measured by using cell counting kit-8 (CCK-8). The results revealed that LPS induced inflammatory responses, as p-p65/p65 and p-IκBα/IκBα ratios and TNF-α and IL-1β production was increased in the CMECs. Both Bcl-2/Bax ratio and cell viability were decreased and caspase-3 cleaved following LPS treatment, indicating apoptosis of CMECs. Moreover, both LPS and baicalin increased HSP72 expression of the CMECs. However, cellular inflammatory responses and apoptosis were significantly reduced in baicalin treated CMECs. In conclusion, baicalin ameliorated inflammation and apoptosis of the CMECs induced by LPS via inhibiting NF-κB activation and up regulation of HSP72.

Effect of baicalin on hippocampal damage in kainic acid-induced epileptic mice

The aim of the present study was to determine the effect of baicalin on the expression of miR-497 and its target B-cell lymphoma-2 (Bcl-2) in the hippocampus of kainic acid (KA)-induced epileptic mice. To establish status epilepticus (SE), 0.1 µg/5 µl KA was injected into the lateral cerebral ventricle in mice, which then received an intraperitoneal injection of baicalin (100 mg/kg) after 1 and 8 h. Hematoxylin and eosin staining was used to observe the pathological changes in morphology and neuronal apoptosis was determined by terminal transferase-mediated dUTP nick end-labeling staining. Western blot analysis was used to detect the expression of Bcl-2 and cleaved caspase-3 proteins in the hippocampus, while reverse transcription-quantitative polymerase chain reaction was used to quantify hippocampal miR-497 expression. The results showed that baicalin significantly attenuated neuronal damage and apoptosis in the hippocampus 72 h after SE. In addition, baicalin decreased SE-induced expression of miR-497 and cleaved caspase-3 protein, while upregulating the expression of Bcl-2 protein. In conclusion, the present results suggest that baicalin possesses potent antiapoptotic properties and attenuates hippocampal injury in mice after SE, which may be associated with the downregulation of miR-497 and cleaved caspase-3 and the upregulation of Bcl-2.

The anti-malaria drug artesunate inhibits cigarette smoke and ovalbumin concurrent exposure-induced airway inflammation and might reverse glucocorticoid insensitivity

BACKGROUND

The anti-malaria drug artesunate has been shown to attenuate experimental allergic asthma via inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. This study was to further determine the effects of artesunate on cigarette smoke and ovalbumin (OVA) concurrent exposure-induced airway inflammation, the related mechanism, and glucocorticoid insensitivity.

METHODS AND RESULTS

In vivo: Female BALB/c mice concurrently exposed to cigarette smoke and OVA developed mixed eosinophilic and neutrophilic airway inflammation. Airway hyper-responsiveness, total and differential cell counts, and pro-inflammatory cytokine levels (interleukin (IL)-4, IL-8, IL-13 and tumor necrosis factor (TNF)-α) in bronchoalveolar lavage fluid (BALF) were measured. Lung tissue sections were stained for histological analysis, and proteins were extracted for Western blotting. Artesunate reduced methacholine-induced airway hyper-responsiveness, suppressed pulmonary inflammation cell recruitment and IL-4, IL-8, IL-13 and TNF-α levels, selectively inhibited PI3Kδ/Akt pathway, and restored HDAC2 activity. In vitro: BEAS-2B cells were exposed to cigarette smoke extract (CSE) for 6h and then stimulated with TNF-α overnight. Glucocorticoid sensitivity was evaluated by the inhibition of TNF-α-induced IL-8 production by dexamethasone. CSE reduced the effects of dexamethasone on TNF-α-induced IL-8 production in BEAS-2B cells, while artesunate reversed CSE-induced glucocorticoid insensitivity and restored HDAC2 deactivation induced by CSE.

CONCLUSION

Artesunate ameliorated cigarette smoke and OVA concurrent exposure-induced airway inflammation, inhibited the PI3Kδ/Akt pathway, restored HDAC2 activity, and reversed CSE-induced glucocorticoid insensitivity in BEAS-2B cells. These findings indicate that artesunate might play a protective role in asthma induced by cigarette smoke and glucocorticoid insensitivity.

Long-term effects of acupuncture treatment on airway smooth muscle in a rat model of smoke-induced chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is one of the most common lung diseases. It is a chronic inflammatory process characterised by airway obstruction and progressive lung inflammation, associated with difficulty breathing and insensitivity to corticosteroid therapy. Although there is some preliminary evidence to suggest a beneficial effect of acupuncture on COPD, its mechanism of action has not been investigated. Our aim was to examine the anti-inflammatory effects of acupuncture in a rat model of COPD induced by exposure to cigarette smoke (CS).

Methods

Sixty Sprague–Dawley rats were exposed to the smoke of 15 cigarettes for 1 h/day, 6 days/week for 3 months to induce COPD and treated with acupuncture at BL13 (Feishu), BL23 (Shenshu) and Dingchuan (COPD+Acupuncture, n=15), sham acupuncture (COPD+Sham, n=15) or left untreated (n=15). Exposed rats were compared with controls not exposed to CS (control, n=15). Pulmonary function was measured, and tumour necrosis factor-α (TNF-α) and interleukin-8 (IL-8) levels were determined in bronchoalveolar lavage fluid by ELISA. Histone deacetylase 2 (HDAC2) protein and mRNA expression were examined in lung tissue and in bronchus.

Results

Acupuncture treatment appeared to protect pulmonary function and reduce the COPD-induced inflammatory response by decreasing cell inflammation and the production of TNF-α and IL-8. Acupuncture also enhanced HDAC2 mRNA and protein expression, suggesting a possible direct effect on protein structure through post-translational modifications.

Conclusions

Our results suggest that acupuncture regulates inflammatory cytokines and contributes to lung protection in a rat model of smoke-induced COPD by modulating HDAC2.

Effect of baicalin-copper on the induction of apoptosis in human hepatoblastoma cancer HepG2 cells

The medical properties of baicalin have been well known for many years. However, the discovery that baicalin in the presence of metal ions is more effective than baicalin alone changed the course of drug research. The present study was designed to investigate the effect and possible mechanism of apoptosis induced by baicalin-copper in a human hepatoblastoma cancer cell line (HepG2) and in vivo. This study demonstrated that baicalin-copper suppresses the proliferation of HepG2 cells in a dose-dependent manner. Intraperitoneal injection of baicalin-copper resulted in a significant decrease in tumor growth in xenografts in nude mice. Acridine orange staining and flow cytometry analysis demonstrated that baicalin-copper induced apoptosis in HepG2 cells and caused cells to arrest in G2-M phase of the cell cycle. Furthermore, baicalin-copper treatment significantly increased the Bax/Bcl-2 ratio and p38 levels, as well as decreased the expression of caspase-3, p-PI3K, p-Akt and p-mTOR (P < 0.01). All of the evidences above indicate that baicalin-copper induces apoptosis in HepG2 cells by down-regulating the PI3K/Akt/mTOR signaling pathway.

Effects of baicalin against UVA-induced photoaging in skin fibroblasts

Ultraviolet A (UVA) radiation contributes to skin photoaging. Baicalin, a plant-derived flavonoid, effectively absorbs UV rays and has been shown to have anti-oxidant and anti-inflammatory properties that may delay the photoaging process. In the current study, cultured human skin fibroblasts were incubated with 50 μg/ml baicalin 24 hours prior to 10 J/cm(2) UVA irradiation. In order to examine the efficacy of baicalin treatment in delaying UVA-induced photoaging, we investigated aging-related markers, cell cycle changes, anti-oxidant activity, telomere length, and DNA damage markers. UVA radiation caused an increased proportion of β-Gal positive cells and reduced telomere length in human skin fibroblasts. In addition, UVA radiation inhibited TGF-β1 secretion, induced G1 phase arrest, reduced SOD and GSH-Px levels, increased MDA levels, enhanced the expression of MMP-1, TIMP-1, p66, p53, and p16 mRNA, reduced c-myc mRNA expression, elevated p53 and p16 protein expression, and reduced c-myc protein expression. Baicalin treatment effectively protected human fibroblasts from these UVA radiation-induced aging responses, suggesting that the underlying mechanism involves the inhibition of oxidative damage and regulation of the expression of senescence-related genes, including those encoding for p53, p66(Shc) and p16.

Baicalin, a component of Scutellaria baicalensis, alleviates anorexia and inhibits skeletal muscle atrophy in experimental cancer cachexia

Inflammatory responses are key contributors to cancer cachexia and foster a complex cascade of biological outcomes. Baicalin is a natural compound derived from Scutellaria baicalensis that possesses anti-inflammatory properties in many diseases; therefore, the aim of this study was to verify whether baicalin could ameliorate cachexia in a CT26 adenocarcinoma-induced model. Tumour-bearing and control mice were injected with CT26 adenocarcinoma cells and phosphate-buffered saline (PBS), respectively, and baicalin was administered intraperitoneally for 15 days. During the study, food intake, body weight, major organ weight, gastrocnemius muscle weight, tibialis muscle weight, epididymal fat weight and serum cytokine levels were measured and evaluated. Additionally, the expression of two E3 ubiquitin ligases and NF-κB pathway proteins were detected by Western blot. The total food intake in tumour-bearing mice receiving baicalin from days 1-16, as well as the average food intake on days 10-16, were less than normal but were significantly higher than in vehicle-treated tumour-bearing mice. Loss of tumour-free body mass in vehicle-treated tumour-bearing mice was significantly increased compared with control mice and tumour-bearing mice receiving baicalin. Serum cytokines, including tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6), were lowered in tumour-bearing mice treated with baicalin. Gastrocnemius muscle, epididymal fat, heart and kidney weight were significantly greater in the baicalin treatment groups compared with the vehicle-treated tumour-bearing mice. In addition, the expression of two E3 ubiquitin ligases, as well as phospho-p65, was significantly downregulated, whereas the expression of IκBα was up-regulated in tumour-bearing mice treated with baicalin, as determined by Western blotting. The present study demonstrates that baicalin effectively ameliorates anorexia by inhibiting cytokine expression and prevents skeletal muscle atrophy most likely by inhibiting activation of NF-κB in an experimental cancer cachexia model, suggesting that baicalin represents a promising natural medicine for treating cancer-induced cachexia.

Anti-inflammatory and Antimicrobial Effects of Heat-Clearing Chinese Herbs: A Current Review

Inflammation is a normal immune response; but if the body's regulation of inflammation is dysfunctional, then it will have an adverse effect on the body. Although use of modern drugs for inflammation has a relieving effect, it is still unsatisfactory. Moreover, the emergence of drug-resistant strains and even new kinds of microorganisms is causing significant morbidity and mortality. Recently, more attention has been focused on herbal medicine to treat various diseases because of the ability of the herbs to affect multiple target signaling pathways and their multiple mechanisms of action. Thus, a large number of studies have reported on the anti-inflammatory and antimicrobial effects of the traditional Chinese herbs. Literature survey was performed by conducting systematic electronic search in PubMed, Science Direct, Google Scholar, and in books. This review has listed 11 heat-clearing Chinese herbs (HCCHs) including Scutellaria baicalensis ( Huáng Qín), Coptis chinensis ( Huáng Lián), Flos Lonicerae ( Jīn Yín Hūa), Forsythia suspensa ( Lián Qiào), Isatidis Folium ( Dà Qīn Yè), Radix Isatidis ( Bǎn Lán Gēn), Viola yedoensis ( Zǐ Huā Dì Dīn), Pulsatilla Radix ( Bái Tóu Wēn), Andrographis paniculata ( Chuān Xīn Lián), Houttuynia cordata ( Yú Xīng Cǎo), and Patrinia Herba ( Bài Jiàn Cǎo), which have anti-inflammatory and antimicrobial effects, and has described their effects through different mechanisms of action and multiple targets. Their ability to affect multiple target signaling pathways and their potential mechanisms of action contributing to their anti-inflammatory and antimicrobial activity may be related to their action of removing heat and counteracting toxicity. Further studies are needed on the collection of HCCHs to know the detailed mechanism of action of herbs in this group for the assessment of effective drug.

Flavonoids from each of the six structural groups reactivate BRM, a possible cofactor for the anticancer effects of flavonoids

Flavonoids have been extensively studied and are well documented to have anticancer effects, but it is not entirely known how they impact cellular mechanisms to elicit these effects. In the course of this study, we found that a variety of different flavonoids readily restored Brahma (BRM) in BRM-deficient cancer cell lines. Flavonoids from each of the six different structural groups were effective at inducing BRM expression as well as inhibiting growth in these BRM-deficient cancer cells. By blocking the induction of BRM with shRNA, we found that flavonoid-induced growth inhibition was BRM dependent. We also found that flavonoids can restore BRM functionality by reversing BRM acetylation. In addition, we observed that an array of natural flavonoid-containing products both induced BRM expression as well as deacetylated the BRM protein. We also tested two of the BRM-inducing flavonoids (Rutin and Diosmin) at both a low and a high dose on the development of tumors in an established murine lung cancer model. We found that these flavonoids effectively blocked development of adenomas in the lungs of wild-type mice but not in that of BRMnull mice. These data demonstrate that BRM expression and function are regulated by flavonoids and that functional BRM appears to be a prerequisite for the anticancer effects of flavonoids both in vitro and in vivo.

Structure-activity association of flavonoids in lung diseases

Flavonoids are polyphenolic compounds classified into flavonols, flavones, flavanones, isoflavones, catechins, anthocyanidins, and chalcones according to their chemical structures. They are abundantly found in Nature and over 8,000 flavonoids have from different sources, mainly plant materials, have been described. Recently reports have shown the valuable effects of flavonoids as antiviral, anti-allergic, antiplatelet, antitumor, antioxidant, and anti-inflammatory agents and interest in these compounds has been increasing since they can be helpful to human health. Several mechanisms of action are involved in the biological properties of flavonoids such as free radical scavenging, transition metal ion chelation, activation of survival genes and signaling pathways, regulation of mitochondrial function and modulation of inflammatory responses. The anti-inflammatory effects of flavonoids have been described in a number of studies in the literature, but not frequently associated to respiratory disease. Thus, this review aims to discuss the effects of different flavonoids in the control of lung inflammation in some disorders such as asthma, lung emphysema and acute respiratory distress syndrome and the possible mechanisms of action, as well as establish some structure-activity relationships between this biological potential and chemical profile of these compounds.

Flavonoid components in Scutellaria baicalensis inhibit nicotine-induced proliferation, metastasis and lung cancer-associated inflammation in vitro

The objective of the present study was to investigate the therapeutic efficacy of flavonoid components in Scutellaria baicalensis on proliferation, metastasis and lung cancer-associated inflammation during nicotine induction in the A549 and H1299 lung cancer cell lines. After experimental period, augmentation of proliferation was observed, accompanied by marked decrease in apoptotic cells in nicotine-induced lung cancer cells; additionally, nicotine-exposed cells exhibited increased invasive and migratory abilities based on invasion and wound-healing assay. Flavones in Scutellaria, baicalin, baicalein and wogonin significantly counteracted the above deleterious changes. Moreover, assessment of tumor apoptotic and metastatic factors on mRNA levels by quantitative PCR and protein levels by western blotting revealed that these phytochemical treatments effectively negated nicotine-induced upregulated expression of bcl-2, bcl-2/bax ratio, caspase-3, matrix metalloproteinase (MMP)-2 and MMP-9 as well as downregulated expression of bax. Further analysis of inflammatory markers such as tumor necrosis factor (TNF)-α and interleukin (IL)-6 in cell culture supernatant and mRNA and protein expression of nuclear transcription factor-kappaB (NF-κB) and I kappa B-alpha (IκB-α) was carried out to substantiate the anti-inflammatory effect of flavones in Scutellaria in nicotine-exposed lung cancer cells. The therapeutic effects observed in the present study are attributed to the potent potential against proliferation, metastasis and inflammatory microenvironment by flavonoid components in Scutellaria in nicotine-induced lung cancer cells.

Lipopolysaccharide induces up-regulation of TGF-α through HDAC2 in a rat model of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is characterized by alveolar simplification with decreased alveolar number and increased airspace. Previous studies suggested that transforming growth factor-α (TGF-α) may contribute to arrested alveolar development in BPD. Histone deacetylases (HDACs) control cellular signaling and gene expression. HDAC2 is crucial for suppression of inflammatory gene expression. Here we investigated whether HDAC2 was involved in the arrest of alveolarization, as well as the ability of HDAC2 to regulate TGF-α expression in a rat model of BPD induced by intra-amniotic injection of lipopolysaccharide (LPS). Results showed that LPS exposure led to a suppression of both HDAC1 and HDAC2 expression and activity, induced TGF-α expression, and disrupted alveolar morphology. Mechanistic studies showed that overexpression of HDAC2, but not HDAC1, suppressed LPS-induced TGF-α expression. Moreover, the HDAC inhibitor TSA or downregulation of HDAC2 by siRNA both significantly increased TGF-α expression in cultured myofibroblasts. Finally, preservation of HDAC activity by theophylline treatment improved alveolar development and attenuated TGF-α release. Together, these findings indicate that attenuation of TGF-α-mediated effects in the lung by enhancing HDAC2 may have a therapeutic effect on treating BPD.

Contribution of baicalin on the plasma protein binding displacement and CYP3A activity inhibition to the pharmacokinetic changes of nifedipine in rats in vivo and in vitro

Baicalin purified from the root of Radix scutellariae is widely used in clinical practices. This study aimed to evaluate the effect of baicalin on the pharmacokinetics of nifedipine, a CYP3A probe substrate, in rats in vivo and in vitro. In a randomised, three-period crossover study, significant changes in the pharmacokinetics of nifedipine (2 mg/kg) were observed after treatment with a low (0.225 g/kg) or high (0.45 g/kg) dose of baicalin in rats. In the low- and high-dose groups of baicalin-treated rats, C max of total nifedipine decreased by 40%±14% (P<0.01) and 65%±14% (P<0.01), AUC0-∞ decreased by 41%±8% (P<0.01) and 63%±7% (P<0.01), Vd increased by 85%±43% (P<0.01) and 224%±231% (P<0.01), and CL increased by 97%±78% (P<0.01) and 242%±135% (P<0.01), respectively. Plasma protein binding experiments in vivo showed that C max of unbound nifedipine significantly increased by 25%±19% (P<0.01) and 44%±29% (P<0.01), respectively, and there was a good correlation between the unbound nifedipine (%) and baicalin concentrations (P<0.01). Furthermore, in vitro results revealed that baicalin was a competitive displacer of nifedipine from plasma proteins. In vitro incubation experiments demonstrated that baicalin could also competitively inhibit CYP3A activity in rat liver microsomes in a concentration-dependent manner. In conclusion, the pharmacokinetic changes of nifedipine may be modulated by the inhibitory effects of baicalin on plasma protein binding and CYP3A-mediated metabolism.

The protective effect of baicalin against renal ischemia-reperfusion injury through inhibition of inflammation and apoptosis

Background

Renal ischemia-reperfusion injury (IRI) increases the rates of acute kidney failure, delayed graft function, and early mortality after kidney transplantation. The pathophysiology involved includes oxidative stress, mitochondrial dysfunction, and immune-mediated injury. The anti-oxidation, anti-apoptosis, and anti-inflammation properties of baicalin, a flavonoid glycoside isolated from Scutellaria baicalensis, have been verified. This study therefore assessed the effects of baicalin against renal IRI in rats.

Methods

Baicalin was intraperitoneally injected 30 min before renal ischemia. Serum and kidneys were harvested 24 h after reperfusion. Renal function and histological changes were assessed. Markers of oxidative stress, the Toll-like receptor (TLR)2 and TLR4 signaling pathway, mitochondrial stress, and cell apoptosis were also evaluated.

Results

Baicalin treatment decreased oxidative stress and histological injury, and improved kidney function, as well as inhibiting proinflammatory responses and tubular apoptosis. Baicalin pretreatment also reduced the expression of TLR2, TLR4, MyD88, p-NF-κB, and p-IκB proteins, as well as decreasing caspase-3 activity and increasing the Bcl-2/Bax ratio.

Conclusions

Baicalin may attenuate renal ischemia-reperfusion injury by inhibiting proinflammatory responses and mitochondria-mediated apoptosis. These effects are associated with the TLR2/4 signaling pathway and mitochondrial stress.

Andrographolide antagonizes cigarette smoke extract-induced inflammatory response and oxidative stress in human alveolar epithelial A549 cells through induction of microRNA-218

Andrographolide is a major bioactive labdane diterpenoid isolated from Andrographis paniculata and has protective effects against cigarette smoke (CS)-induced lung injury. This study was done to determine whether such protective effects were mediated through modulation of microRNA (miR)-218 expression. Therefore, we exposed human alveolar epithelial A549 cells to cigarette smoke extract (CSE) with or without andrographolide pretreatment and measured the level of glutathione, nuclear factor-kappaB (NF-κB) activation, proinflammatory cytokine production, and miR-218 expression. We found that andrographolide pretreatment significantly restored the glutathione level in CSE-exposed A549 cells, coupled with reduced inhibitor κB (IκB)-α phosphorylation and p65 nuclear translocation and interleukin (IL)-8 and IL-6 secretion. The miR-218 expression was significantly upregulated by andrographolide pretreatment. To determine the biological role of miR-218, we overexpressed and downregulated its expression using miR-218 mimic and anti-miR-218 inhibitor, respectively. We observed that miR-218 overexpression led to a marked reduction in IκB-α phosphorylation, p65 nuclear accumulation, and NF-κB-dependent transcriptional activity in CSE-treated A549 cells. In contrast, miR-218 silencing enhanced IκB-α phosphorylation and p65 nuclear accumulation in cells with andrographolide pretreatment and reversed andrographolide-mediated reduction of IL-6 and IL-8 production. In addition, depletion of miR-218 significantly reversed the upregulation of glutathione levels in A549 cells by andrographolide. Taken together, our results demonstrate that andrographolide mitigates CSE-induced inflammatory response in A549 cells, largely through inhibition of NF-κB activation via upregulation of miR-218, and thus has preventive benefits in CS-induced inflammatory lung diseases.