Andrographolide protects against cigarette smoke-induced lung inflammation through activation of heme oxygenase-1

Mechanistic exploration of the shenlian formula in the suppression of atherosclerosis progression via network pharmacology and in vivo experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

The Shenlian formula (SL) is a Chinese medicine formula used to curb the development of atherosclerosis (AS) and cardiovascular disease in clinical practice. However, owing to the complexity of compounds and their related multiple targets in traditional Chinese medicine (TCM), it remains difficult and urgent to elucidate the underlying mechanisms at a holistic level.

AIM

To investigate the intrinsic mechanisms by which SL suppresses AS progression and to gain new insight into its clinical use.

METHODS

We proposed a network pharmacology-based workflow to evaluate the mechanism by which SL affects AS via data analysis, target prediction, PPI network construction, GO and KEGG analyses, and a "drug-core ingredient-potential target-key pathway" network. Then, non-targeted lipidomic analysis was performed to explore the differential lipid metabolites in AS rats, revealing the possible mechanism by which SL affects atherosclerotic progression. Moreover, an AS rabbit model was constructed and gavaged for SL intervention. Serum lipid profiles and inflammatory cytokine indices were tested as an indication of the mitigating effect of SL on AS.

RESULTS

A total of 89 bioactive compounds and 298 targets related to SL and AS, which play essential roles in this process, were identified, and a component-target-disease network was constructed. GO and KEGG analyses revealed that SL regulated metabolic pathway, lipids and atherosclerosis, the PI3K-Akt pathway, the MAPK pathway and so on. In vivo experimental validation revealed that a total of 43 different lipid metabolites regulated by SL were identified by non-targeted lipidomics, and glycerophospholipid metabolism was found to be an important mechanism for SL to interfere with AS. SL reduced the plaque area and decreased the levels of inflammatory cytokines (TNF-α and IL-4) and blood lipids (TC, TG, LDL-C, and ApoB) in HFD-induced AS models. In addition, HDL and ApoA1 levels are increased. PLA2 and Lipin1 are highly expressed in AS model, indicating their role in destabilizing glycerophosphatidylcholine metabolism and contributing to the onset and progression of ankylosing spondylitis. Moreover, SL intervention significantly reduced the level of pro-inflammatory cytokines; significantly down-regulated NF-kB/p65 expression, exhibiting anti-inflammatory activity.

CONCLUSION

The Shenlian formula (SL) plays a pivotal role in the suppression of AS progression by targeting multiple pathways and mechanisms. This study provides novel insights into the essential genes and pathways associated with the prognosis and pathogenesis of AS.

In vitro and in vivo study of andrographolide nanoparticles for the treatment of Mycoplasma pneumoniae pneumonia

OBJECTIVE(S)

The emergence of antibiotic resistance has led to suboptimal treatment outcomes for Mycoplasma pneumoniae pneumonia (MPP). Exploring naturally occurring drug components that are both effective against MPP and non-toxic may be a promising choice. This study aimed to investigate the therapeutic effect of andrographolide nanoparticles on pneumonia caused by Mycoplasma pneumoniae infection.

METHODS

Andrographolide alginate-poloxamer nanoparticles (AND-ALG-POL/NPs) were obtained by wet medium grinding, and the characterization and in vitro release of the prepared andrographolide nanoparticles were examined by high performance liquid chromatography, particle size analyzer, zeta potential meter and transmission electron microscopy. The cytotoxicity and anti-inflammatory effects of AND-ALG-POL/NPs were evaluated in vitro by MP-infected lung epithelial cells BEAS-2B. Symptoms of pneumonia, total cell count, total protein content and inflammatory factor levels in BALF were assessed by MP-induced pneumonia in BALB/c mice treated with AND-ALG-POL/NPs, and histopathological studies were performed on lung tissues from experimental animals.

RESULTS

The results showed that the prepared AND-ALG-POL/NPs were homogeneous spherical with a diameter of 180 ± 23 nm, a zeta potential of (-14.4 ± 2.1) mV, an average encapsulation rate of 87.74 ± 0.87 %, and an average drug loading of 13.17 ± 0.54 %. AND-ALG-POL/NPs were capable of slow release in vitro and showed significant inhibitory ability against MP (P < 0.001). However, AND-ALG-POL/NPs were not cytotoxic to normal cells and alleviated MP infection-induced apoptosis and elevated inflammatory factors. In the in vivo experiments, AND-ALG-POL/NPs alleviated the symptoms of pneumonia in MPP mice, reduced the abnormally elevated total cell count, total protein content and inflammatory factor levels in BALF, and alleviated lung tissue edema, inflammatory cell infiltration and apoptosis (P < 0.001). Meanwhile, the therapeutic effects of AND-ALG-POL/NPs on MPP were similar to those of azithromycin (AZM) and higher than those of andrographolide (AND) free monotherapy (P < 0.001).

CONCLUSION

In summary, the prepared AND-ALG-POL/NPs can effectively inhibit MPP in vitro and in vivo, and the effect is similar to that of AZM. Therefore, AND- ALG - POL/NPs have the potential to replace AZM as a potential drug for the treatment of MPP.

Andrographolide induced heme oxygenase-1 expression in MSC-like cells isolated from rat bone marrow exposed to environmental stress

BACKGROUND AND OBJECTIVES

Mesenchymal stem cells (MSC-like cells) are the most important stem cells that are used in transplantation clinically in various applications. The survival rate of MSC-like cells is strongly reduced due to adverse conditions in the microenvironment of transplantation, including environmental stress. Heme oxygenase-1 (HO-1) is a member of the heat shock protein, as well as a stress-induced enzyme, present throughout the body. The present study was conducted to investigate the effect of andrographolide, an active derivative from andrographolide paniculate, on HO-1 expression in mesenchymal stem cells derived from rat bone marrow.

MATERIALS AND METHODS

The rat bone marrow-derived mesenchymal stem cells (BMSC-like cells) were extracted and proliferated in several passages. The identity of MSC-like cells was confirmed by morphological observations and differential tests. The flow cytometry method was used to verify the MSC-specific markers. Isolated MSC-like cells were treated with different concentrations of andrographolide and then exposed to environmental stress. Cell viability was assessed using the MTT colorimetric assay. A real-time PCR technique was employed to evaluate the expression level of HO-1 in the treated MSC-like cells.

RESULTS

Isolated MSC-like cells demonstrated fibroblast-like morphology. These cells in different culture mediums differentiated into osteocytes and adipocytes and were identified using alizarin red and oil red staining, respectively. As well, MSC-like cells were verified by the detection of CD105 surface antigen and the absence of CD14 and CD45 antigens. The results of the MTT assay showed that the pre-treatment of MSC-like cells with andrographolide concentration independently increased the viability and resistance of these cells to environmental stress caused by hydrogen peroxide and serum deprivation (SD). Real-time PCR findings indicated a significant increase in HO-1 gene expression in the andrographolide-receiving groups (p < 0.01).

CONCLUSION

Our results suggest that andrographolide creates a promising strategy for enhancing the quality of cell therapy by increasing the resistance of MSC-like cells to environmental stress and inducing the expression of HO-1.

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.

Protective effect of the effective part of Andrographis paniculata (Burm.f.) Nees on PM2.5-induced lung injury in rats by modulating the NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Andrographis paniculata (Burm.f.) Nees, a traditional Chinese herb, has been widely used in various Asian countries as a treatment for upper respiratory tract infections for centuries.

AIM OF THE STUDY

Continuous inhalation of fine particulate matter (PM_2.5) may induce various respiratory diseases. This study elucidated the protective effect of the effective part of Andrographis paniculata (Burm.f.) Nees (AEP) against PM_2.5-induced lung injury and detailed the underlying mechanism.

MATERIALS AND METHODS

Male Wistar rats were orally administered 0.5% sodium carboxymethylcellulose (CMC-Na), andrographolide (AG) (200 mg/kg) and AEP (100 mg/kg, 200 mg/kg and 400 mg/kg) once a day for 28 days. The rats were intratracheally instilled with PM_2.5 suspension (8 mg/kg) every other day beginning on the 24th day for a total of 3 times. On the 29th day, bronchoalveolar lavage fluid (BALF) was collected to analyze the levels of lactate dehydrogenase (LDH), acid phosphatase (ACP), alkaline phosphatase (AKP), total proteins (TP), tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6). Hematoxylin & eosin staining was conducted to evaluate the pathological changes in the lung tissues. The protein expression of NF-κB p65 in the lung tissues was analyzed by immunohistochemistry staining. Moreover, the nuclear translocation of NF-κB p65 and the phosphorylation of IκBα were analyzed by western blotting.

RESULTS

PM_2.5 exposure caused lung toxicity, which was characterized by pathological injury and increased levels of LDH, ACP, AKP and TP in BALF. Meanwhile, PM_2.5 exposure induced lung inflammatory response, including infiltration of inflammatory cells and increased levels of inflammatory factors, such as TNF-α and IL-6 in BALF. AEP treatment significantly ameliorated the PM_2.5-induced lung toxicity and the inflammatory response in rats. Moreover, AEP significantly inhibited the PM_2.5-induced upregulation of NF-κB p65 protein expression, phosphorylation of IκBα and nuclear translocation of NF-κB p65 in lung tissue. Compared to AG, AEP exhibited a better ability to alleviate PM_2.5-induced pathological damage and decrease the TP level in the BALF.

CONCLUSION

AEP could be used to improve PM_2.5-induced lung injury by modulating the NF-κB pathway, and multicomponent therapy with traditional Chinese medicine may be more effective than single-drug therapy.

Pharmacologic Activities of Plant-Derived Natural Products on Respiratory Diseases and Inflammations

Respiratory inflammation is caused by an air-mediated disease induced by polluted air, smoke, bacteria, and viruses. The COVID-19 pandemic is also a kind of respiratory disease, induced by a virus causing a serious effect on the lungs, bronchioles, and pharynges that results in oxygen deficiency. Extensive research has been conducted to find out the potent natural products that help to prevent, treat, and manage respiratory diseases. Traditionally, wider floras were reported to be used, such as Morus alba, Artemisia indica, Azadirachta indica, Calotropis gigantea, but only some of the potent compounds from some of the plants have been scientifically validated. Plant-derived natural products such as colchicine, zingerone, forsythiaside A, mangiferin, glycyrrhizin, curcumin, and many other compounds are found to have a promising effect on treating and managing respiratory inflammation. In this review, current clinically approved drugs along with the efficacy and side effects have been studied. The study also focuses on the traditional uses of medicinal plants on reducing respiratory complications and their bioactive phytoconstituents. The pharmacological evidence of lowering respiratory complications by plant-derived natural products has been critically studied with detailed mechanism and action. However, the scientific validation of such compounds requires clinical study and evidence on animal and human models to replace modern commercial medicine.

Andrographolide and its derivatives: Current achievements and future perspectives

Natural product andrographolide isolated from the plant Andrographis paniculata shows a plethora of biological activities, including anti-tumor, anti-bacterial, anti-inflammation, anti-virus, anti-fibrosis, anti-obesity, immunomodulatory and hypoglycemic activities. Based on extensive chemical structural modifications, a series of andrographolide derivatives with improved bioavailability and druggability has been developed. Moreover, greater understanding of their mechanisms of action at the molecular and cellular level has been thoroughly investigated. In this review, we give an outlook for the therapeutical potential of andrographolide and its derivatives in diverse diseases and highlighted the drug design, pharmacokinetic and mechanistic studies for the past ten years, together with a brief overview of the pharmacological effects. Notably, we focused to provide a critical enlightenment of the area of andrographolide and its derivatives with the intent of indicating the future perspectives, challenges and limitations. We believe that this review paper will benefit drug discovery where andrographolide was used as a template, shed light on the identification of drug targets for andrographolide and its analogs, as well as increase our knowledge for using them for therapeutic application, including the treatment for various forms of cancers.

Current Trends on Repurposing and Pharmacological Enhancement of Andrographolide

Andrographolide, the main bioactive component separated from Andrographis paniculata in 1951, has been scrutinized with a modern drug discovery approach for anti-inflammatory properties since 1984. Identification of new uses of existing drugs can be facilitated by searching for evidence linking them to known or yet undiscovered drug targets and human disease states to develop new therapeutic indications.Furthermore, a wide spectrum of biological properties of andrographolide such as anticancer, antibacterial, antiviral, hepatoprotective, antioxidant, anti-malarial, anti-atherosclerosis are also reported. However, poor water solubility and instability limit its clinical application. It becomes crucial to enhance its pharmacological function and find a new treatment option for more diseases. Therefore, this article reviews the major recent developments in andrographolide, including repurposing applications in different diseases and underlying mechanisms, particularly focusing on pharmacological enhancement of andrographolide such as derivatives, chemical modifications with potent biological activity and drug delivery. The repurposing and pharmacological enhancement of andrographolide would not only have exciting therapeutic potential to different diseases to facilitate drug marketing, but also decrease the economic burden on healthcare worldwide.

Andrographolide Against Lung Cancer-New Pharmacological Insights Based on High-Throughput Metabolomics Analysis Combined with Network Pharmacology

Andrographolide (Andro) has known to treat various illnesses such as colds, diarrhea, fever and infectious diseases. However, the effect mechanism of Andro is still unclear. Therefore, we used high-throughput metabolomics analysis to discover biomarkers, metabolic profiles and pathways to reveal the pharmacological action and effective mechanism of Andro against lung cancer. The metabolic effects of Andro on lung cancer animal was explored by ultra-performance liquid chromatography-triple-time of flight/mass spectrometry (UPLC-TOF/MS) analysis. Our results showed that Andro exhibited significant protective effects against lung cancer. Compared with control group, a total of 25 metabolites biomarkers was identified in urine of model animals, which 18 of them were regulated toward the normal direction after Andro treatment, and network pharmacology analysis showed that they were related with 570 proteins. Biological pathways analysis showed that the 11 metabolism pathways were regulated by Andro treatment in lung cancer mouse, and amino acid metabolism and arachidonic acid metabolism have great potential as target pathways for Andro against lung cancer. It revealed that high-throughput metabolomics combined with network pharmacology analysis provides deeply insight into the therapeutic mechanisms of natural product for promoting medicine development and disease treatment.

Andrographolide Protects against HG-Induced Inflammation, Apoptosis, Migration, and Impairment of Angiogenesis via PI3K/AKT-eNOS Signalling in HUVECs

Andrographolide (Andr) is a major component isolated from the plant Andrographis paniculata. Inflammation, apoptosis, and impaired angiogenesis are implicated in the pathogenesis of high glucose (HG)-induced injury of vascular endotheliocytes. Our study is aimed at evaluating the effect of Andr on HG-induced HUVEC injury and the underlying mechanism. HUVECs were exposed to HG levels (33 mM) and treated with Andr (0, 12.5, 25, and 50 μM). Western blot analysis, real-time PCR, immunofluorescence staining, the scratch test, and the tube formation assay were performed to assess the effects of Andr. We discovered that Andr inhibited the inflammatory response (IL-1β, IL-6, and TNFα), decreased the apoptosis ratio and cell migration, and promoted tube formation in response to HG stimulation. Andr ameliorated the levels of phosphorylated PI3K (p-PI3K), phosphorylated AKT (p-AKT), and phosphorylated eNOS (p-eNOS). The expression of vascular endothelial growth factor (VEGF) protein, a vital factor in angiogenesis, was improved by Andr treatment under HG stimulation. LY294002 is a blocker of PI3K, MK-2206 2HCI (MK-2206) is a highly selective AKT inhibitor, and L-NAME is a suppressor of eNOS, all of which significantly reduce Andr-mediated protective effects in vitro. Hence, Andr may be involved in regulating HG-induced injury by activating PI3K/AKT-eNOS signalling in HUVECs.

Is there a future for andrographolide to be an anti-inflammatory drug? Deciphering its major mechanisms of action

Andrographis paniculata has long been part of the traditional herbal medicine system in Asia and in Scandinavia. Andrographolide was isolated as a major bioactive constituent of A. paniculata in 1951, and since 1984, andrographolide and its analogs have been scrutinized with modern drug discovery approach for anti-inflammatory properties. With this accumulated wealth of pre-clinical data, it is imperative to review and consolidate different sources of information, to decipher the major anti-inflammatory mechanisms of action in inflammatory diseases, and to provide direction for future studies. Andrographolide and its analogs have been shown to provide anti-inflammatory benefits in a variety of inflammatory disease models. Among the diverse signaling pathways investigated, inhibition of NF-κB activity is the prevailing anti-inflammatory mechanism elicited by andrographolide. There is also increasing evidence supporting endogenous antioxidant defense enhancement by andrographolide through Nrf2 activation. However, the exact pathway leading to NF-κB and Nrf2 activation by andrographolide has yet to be elucidated. Validation and consensus on the major mechanistic actions of andrographolide in different inflammatory conditions are required before translating current findings into clinical settings. There are a few clinical trials conducted using andrographolide in fixed combination formulation which have shown anti-inflammatory benefits and good safety profile. A concerted effort is definitely needed to identify potent andrographolide lead compounds with improved pharmacokinetics and toxicological properties. Taken together, andrographolide and its analogs have great potential to be the next new class of anti-inflammatory agents, and more andrographolide molecules are likely moving towards clinical study stage in the near future.

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.

Fabrication and in vitro/in vivo evaluation of amorphous andrographolide nanosuspensions stabilized by d-α-tocopheryl polyethylene glycol 1000 succinate/sodium lauryl sulfate

Andrographolide (ADG) is a diterpenoid isolated from Andrographis paniculata with a wide spectrum of biological activities, including anti-inflammatory, anticancer and hepatoprotective effects. However, its poor water solubility and efflux by P-glycoprotein have resulted in lower bioavailability. In this study, ADG nanosuspensions (ADG-NS) were prepared using a wet media milling technique followed by freeze drying. d-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS), a surfactant that inhibits P-glycoprotein function, and sodium lauryl sulfate were used as surface stabilizers. A Box-Behnken design was used to optimize the nanosuspension preparation. The products of these optimal preparation conditions were amorphous and possessed much faster dissolution in vitro than a coarse powder of ADG. The particle size and redispersibility index of the freeze-dried ADG-NS were 244.6±3.0 nm and 113%±1.14% (n=3), respectively. A short-term stability study indicated that the freeze-dried ADG-NS could remain highly stable as nanosuspensions during the testing period. A test of transport across a Caco-2 cell monolayer revealed that the membrane permeability (P_app) of ADG-NS was significantly higher than the permeability of the ADG coarse powder or ADG-NS without TPGS (P<0.01). Compared to the ADG coarse powder, a physical mixture, commercial dripping pills and ADG-NS without TPGS, ADG-NS exhibited significantly higher plasma exposure with significant enhancements in C_max and area under the curve of plasma concentration versus time from zero to the last sampling time (AUC_0-t ) (P<0.01). An evaluation of the anti-inflammatory effect on Carr-induced paw edema demonstrated that the ADG-NS were more effective in reducing the rate of paw swelling, producing a greater increase in the serum levels of nitric oxide (NO), Interleukin-1 (IL-1) and tumor necrosis factor-α (TNF-α) (P<0.01) and an increase in superoxide dismutase activity (P<0.05) compared to the ADG coarse powder. This study indicated that nanosuspensions could act as an effective delivery device for ADG to enhance its oral bioavailability and biological efficacy.

Cigarette Smoke-Induced Lung Disease Predisposes to More Severe Infection with Nontypeable Haemophilus influenzae: Protective Effects of Andrographolide

Cigarette smoke (CS) is associated with many maladies, one of which is chronic obstructive pulmonary disease (COPD). As the disease progresses, patients are more prone to develop COPD exacerbation episodes by bacterial infection, particularly to nontypeable Haemophilus influenza (NTHi) infection. The present study aimed to develop a CS-exposed mouse model that increases inflammation induced by NTHi challenge and investigate the protective effects of andrographolide, a bioactive molecule with anti-inflammatory and antioxidant properties isolated from the plant Andrographis paniculata. Female BALB/c mice exposed to 2 weeks of CS followed by a single intratracheal instillation of NTHi developed increased macrophage and neutrophil pulmonary infiltration, augmented cytokine levels, and heightened oxidative damage. Andrographolide effectively reduced lung cellular infiltrates and decreased lung levels of TNF-α, IL-1β, CXCL1/KC, 8-OHdG, matrix metalloproteinase-8 (MMP-8), and MMP-9. The protective actions of andrographolide on CS-predisposed NTHi inflammation might be attributable to increased nuclear factor erythroid-2-related factor 2 (Nrf2) activation and decreased Kelch-like ECH-associated protein 1 (Keap1) repressor function, resulting in enhanced gene expression of antioxidant enzymes including heme oxygenase-1 (HO-1), glutathione reductase (GR), glutathione peroxidase-2 (GPx-2), glutamate-cysteine ligase modifier (GCLM), and NAD(P)H quinone oxidoreductase 1 (NQO1). Taken together, these findings strongly support a therapeutic potential for andrographolide in preventing lung inflammation caused by NTHi in cigarette smokers.

Effects of tanshinone IIA on fibrosis in a rat model of cirrhosis through heme oxygenase-1, inflammation, oxidative stress and apoptosis

Tanshinone IIA is extracted from the root of Salvia miltiorrhiza and used in traditional Chinese medicine for its anti-inflammatory activity and antioxidant effects. The aim of the present study was to investigate the potential protective effects of tanshinone IIA against fibrosis in a rat model of cirrhosis and to elucidate the underlying mechanisms. Male Sprague Dawley rats were used as the model of cirrhosis in the present study. In the cirrhotic rats, the extent of fibrosis, levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), heme oxygenase-1 (HO-1) protein expression, serum levels of nuclear factor (NF)-κB, tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-PX), and the protein expression levels of phosphorylated-p38 mitogen-activated protein kinase (MAPK) were all significantly increased. However, the serum malondialdehyde (MDA) activity and protein kinase B (Akt) protein expression were suppressed in cirrhotic rats compared with the sham (control) group. Compared with the cirrhotic group, administration of tanshinone IIA reduced the extent of fibrosis, levels of ALT and AST, HO-1 protein expression, serum NF-κB, TNF-α, IL-1β and IL-6 levels, and the activity of SOD, CAT and GSH-PX. Furthermore, administration of tanshinone IIA significantly increased the inhibition of the serum MDA activity and the Akt protein expression in cirrhotic rats compared with those in the cirrhotic group. The protective effect of tanshinone IIA suppresses fibrosis in a rat model of cirrhosis, and reduces inflammation and oxidative stress, via the HO-1, Akt and p38 MAPK signaling pathway.

Andrographolide inhibits multiple myeloma cells by inhibiting the TLR4/NF-κB signaling pathway

Andrographolide is an active component from the extract of Andrographis paniculata [(Burm.f) Nees], a medicinal plant from the Acanthaceae family. Pharmacological studies have revealed that andrographolide possesses anti-bacterial, anti-inflammatory, anti-viral, immune regulatory and hepatoprotective properties, and is efficacious in the treatment of cardiovascular diseases, while exhibiting low toxicity and low cost. The present study aimed to determine the inhibitory effects of andrographolide on the growth of multiple myeloma (MM) cells and its possible impact on the Toll-like receptor (TLR)4/nuclear factor (NF)-κB signaling pathway. Cell proliferation was detected using an MTT assay, cellular apoptosis was measured using flow cytometry, and caspase-9/3 activation were assessed using colorimetric assay kits. Furthermore, TLR4 and NF-κB protein expression was determined by western blot analysis. The results revealed that andrographolide reduced the proliferation, while increasing cellular apoptosis and caspase-9/3 activation of MM cells, in addition to downregulating the expression of TLR4 and NF-κB protein. Of note, TLR4- or NF-κB-targeting small-interfering (si)RNA enhanced the andrographolide-induced inhibition of cell proliferation and induction of apoptosis of MM cells. The results of the present study therefore suggested that andrographolide inhibited multiple myeloma cells via the TLR4/NF-κB signaling pathway.

Emodin Attenuates Cigarette Smoke Induced Lung Injury in a Mouse Model via Suppression of Reactive Oxygen Species Production

Emodin has antioxidative activities. Here, we investigated the effects of emodin on cigarette smoke (CS)-induced acute lung inflammation. Mice (C57BL/6) were exposed to CS. Emodin was administrated with intraperitoneal bolus injection of emodin (20 or 40 mg/kg) daily 1 h before CS exposure. Emodin inhibited CS-induced inflammatory cells infiltration in mouse lungs, especially at 40 mg/kg. Moreover, emodin resulted in significant reductions in total bronchoalveolar lavage fluid (BALF) cells, as compared with air exposure control, coupled with decreases in BALF cytokines. The activities of superoxide dismutase, catalase, and glutathione peroxidase were remarkably enhanced by emodin in CS-exposed mice. Emodin enhanced CS-induced expression of heme oxygenase-1 and nuclear factor-erythroid 2-related factor-2 (both are antioxidative genes) at both mRNA and protein levels, and profoundly promoted their activities in CS-treated mice. Collectively, our results suggested that emodin protects mouse lung from CS-induced lung inflammation and oxidative damage, most likely through its antioxidant activity.

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.