Salvianolic Acid B Attenuates Experimental Pulmonary Fibrosis through Inhibition of the TGF-β Signaling Pathway

pH-responsive hydrogel with dual-crosslinked network of polyvinyl alcohol/boric acid for controlled release of salvianolic acid B: novel pro-regenerative mechanisms in scar inhibition and wound healing

This study investigates a novel pH-responsive hydrogel composed of polyvinyl alcohol (PVA) and boric acid (BA) designed for the controlled release of salvianolic acid B (SAB), addressing the critical challenge of scar formation and skin regeneration. The dual-crosslinked network architecture of the hydrogel exhibits remarkable pH sensitivity, enabling it to achieve a peak SAB release within 48 hours in the acidic microenvironment characteristic of early-stage wound healing. In vitro assessments demonstrated that the PVA-BA-SAB hydrogel significantly inhibits fibroblast activation and mitigates abnormal collagen deposition, effectively preventing excessive scar formation. Transcriptome sequencing reveals the potential role of PVA-BA-SAB hydrogel in balancing TGF-β and Wnt signaling pathways. Furthermore, in vivo studies revealed enhanced tissue regeneration, characterized by improved collagen organization and increased vascularization, as well as the promotion of mature hair follicle development. The hydrogel's biocompatibility, mechanical robustness and adhesive properties were also thoroughly evaluated, confirming its suitability for clinical applications. These findings suggest that the PVA-BA-SAB hydrogel fully exerts the excellent characteristics of biomaterials and maximizes the pharmacological effect of SAB. Our innovative drug delivery system not only facilitates enhanced wound healing but also offers a strategic approach to minimize scarring. This research provides valuable insights into innovative therapeutic strategies for effective wound management and tissue repair.

Novel therapeutic strategies and drugs for idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease of unknown etiology. Currently, drugs used to treat IPF in clinical practice exhibit severe side effects and limitations. To address these issues, this paper discusses the therapeutic effects of preclinical targeted drugs (such as STAT3 and TGF-β/Smad pathway inhibitors, chitinase inhibitors, PI3K and phosphodiesterase inhibitors, etc.) and natural products on IPF. Through a summary of current research progress, it is found that natural products possess multitarget effects, stable therapeutic efficacy, low side effects, and nondrug dependence. Furthermore, we discuss the significant prospects of natural product molecules in combating fibrosis by influencing the immune system, expecting that current analytical data will aid in the development of new drugs or the investigation of active ingredients in natural products for potential IPF treatments in the future.

Monomeric compounds from natural products for the treatment of pulmonary fibrosis: a review

Pulmonary fibrosis (PF) is the end stage of lung injury and chronic lung diseases that results in diminished lung function, respiratory failure, and ultimately mortality. Despite extensive research, the pathogenesis of this disease remains elusive, and effective therapeutic options are currently limited, posing a significant clinical challenge. In addition, research on traditional Chinese medicine and naturopathic medicine is hampered by several complications due to complex composition and lack of reference compounds. Natural product monomers, possessing diverse biological activities and excellent safety profiles, have emerged as potential candidates for preventing and treating PF. The effective anti-PF ingredients identified can be generally divided into flavonoids, saponins, polysaccharides, and alkaloids. Specifically, these monomeric compounds can attenuate inflammatory response, oxidative stress, and other physiopathological processes of the lung through many signaling pathways. They also improve pulmonary factors. Additionally, they ameliorate epithelial-mesenchymal transition (EMT) and fibroblast-myofibroblast transdifferentiation (FMT) by regulating multiple signal amplifiers in the lungs, thereby mitigating PF. This review highlights the significant role of monomer compounds derived from natural products in reducing inflammation, oxidative stress, and inhibiting EMT process. The article provides comprehensive information and serves as a solid foundation for further exploration of new strategies to harness the potential of botanicals in the treatment of PF.

Salvianolic acid B in fibrosis treatment: a comprehensive review

Fibrosis is a public health issue of great concern characterized by the excessive deposition of extracellular matrix, leading to the destruction of parenchymal tissue and organ dysfunction that places a heavy burden on the global healthcare system due to its high incidence, disability, and mortality. Salvianolic acid B (SalB) has positively affected various human diseases, including fibrosis. In this review, we concentrate on the anti-fibrotic effects of SalB from a molecular perspective while providing information on the safety, adverse effects, and drug interactions of SalB. Additionally, we discuss the innovative SalB formulations, which give some references for further investigation and therapeutic use of SalB's anti-fibrotic qualities. Even with the encouraging preclinical data, additional research is required before relevant clinical trials can be conducted. Therefore, we conclude with recommendations for future studies. It is hoped that this review will provide comprehensive new perspectives on future research and product development related to SalB treatment of fibrosis and promote the efficient development of this field.

Global research status and trends of interactions between Traditional Chinese medicine and pulmonary fibrosis: A new dawn in treatment

Background

Pulmonary fibrosis (PF) remains a major sequela of COVID-19, yet its pharmacotherapy remains unsatisfactory. Recently, Traditional Chinese medicine (TCM) has garnered increasing recognition among patients and researchers because of its few side effects and efficacy. The objective of this study is to use bibliometric analysis to explore the current research landscape and emerging trajectories of TCM treating PF(TCM/PF) researches, and comprehensively evaluate publications with substantial citations within the domain of TCM/PF.

Materials and methods

TCM/PF publications from 1996 to June 15, 2023 were identified by a comprehensive search of the Web of Science Core Collection (WoSCC). The Bibliometrix of Origin, CiteSpace, Gephi, dycharts and VOSviewer were used for bibliometric analysis.

Results

A total of 358 papers were included. A rapid increase in the number of papers after 2013 was observed. China had the highest publication output and research contributions in this field. Beijing University of Traditional Chinese Medicine and Nanjing University of Traditional Chinese Medicineare leaders in productive research of this field. Nanjing University of Traditional Chinese Medicine had the highest citations (227). LI JIANSHENG from Henan University of Chinese Medicine was the most prolific author (8), with the highest number of citations (61), and TONG XIAO LIN from China Academy of Chinese Medical Sciences had the highest H-index (30). The leading journal publishing the most research (37) is Frontiers in Pharmacology and the Journal of Ethnopharmacology had the highest total citations (486). Burst analysis of keywords revealed three distinct phases of research. 1996 to 2013 marked the nascent stage of TCM/PF research; from 2014 to 2018, studies gradually focused on the underlying mechanisms governing TCM/PF. The most significant phase occurred from 2019 onward, where TCM/PF exhibited an explosive growth trend. This progression signifies a transition from foundational explorations to a comprehensive understanding of the mechanisms involved, ultimately leading to the current surge in research activities focused on TCM/PF. Notable research teams of this stage, led by LI JIAN SHENG and TONG XIAO LIN, have been at the forefront of advancing TCM/PF research. Their studies on Jinshui Huanxian formula and Qimai Feiluoping decoction have been pivotal in advancing the frontier of research in this domain. Furthermore, the monomeric compounds, including emodin, curcumin, salvianolic acid, baicalin, and oxymatrine, have sustained longstanding prominence.

Conclusions

This study gained insight into the research status, focal areas and evolving trends of global TCM/PF research. It also identified the most cited articles in TCM/PF and analyzed their characteristics, which may hold significant relevance for both clinical researchers and practitioners on future directions in this field.

A two-way street - cellular metabolism and myofibroblast contraction

Tissue fibrosis is characterised by the high-energy consumption associated with myofibroblast contraction. Although myofibroblast contraction relies on ATP production, the role of cellular metabolism in myofibroblast contraction has not yet been elucidated. Studies have so far only focused on myofibroblast contraction regulators, such as integrin receptors, TGF-β and their shared transcription factor YAP/TAZ, in a fibroblast-myofibroblast transition setting. Additionally, the influence of the regulators on metabolism and vice versa have been described in this context. However, this has so far not yet been connected to myofibroblast contraction. This review focuses on the known and unknown of how cellular metabolism influences the processes leading to myofibroblast contraction and vice versa. We elucidate the signalling cascades responsible for myofibroblast contraction by looking at FMT regulators, mechanical cues, biochemical signalling, ECM properties and how they can influence and be influenced by cellular metabolism. By reviewing the existing knowledge on the link between cellular metabolism and the regulation of myofibroblast contraction, we aim to pinpoint gaps of knowledge and eventually help identify potential research targets to identify strategies that would allow switching tissue fibrosis towards tissue regeneration.

Salvianolic Acid B Significantly Suppresses the Migration of Melanoma Cells via Direct Interaction with β-Actin

Melanoma is the most aggressive and difficult to treat of all skin cancers. Despite advances in the treatment of melanoma, the prognosis for melanoma patients remains poor, and the recurrence rate remains high. There is substantial evidence that Chinese herbals effectively prevent and treat melanoma. The bioactive ingredient Salvianolic acid B (SAB) found in Salvia miltiorrhiza, a well-known Chinese herbal with various biological functions, exhibits inhibitory activity against various cancers. A375 and mouse B16 cell lines were used to evaluate the main targets and mechanisms of SAB in inhibiting melanoma migration. Online bioinformatics analysis, Western blotting, immunofluorescence, molecular fishing, dot blot, and molecular docking assays were carried out to clarify the potential molecular mechanism. We found that SAB prevents the migration and invasion of melanoma cells by inhibiting the epithelial-mesenchymal transition (EMT) process of melanoma cells. As well as interacting directly with the N-terminal domain of β-actin, SAB enhanced its compactness and stability, thereby inhibiting the migration of cells. Taken together, SAB could significantly suppress the migration of melanoma cells via direct binding with β-actin, suggesting that SAB could be a helpful supplement that may enhance chemotherapeutic outcomes and benefit melanoma patients.

Tanshinone IIA ameliorates the development of dermal fibrosis in systemic sclerosis

OBJECTIVES

We previously revealed the role of tanshinone IIA (TAN IIA) on endothelial cells and the impact of TAN IIA on the endothelial-to-mesenchymal transition in systemic sclerosis (SSc). In this study, we sought to further determine whether TAN IIA can directly act on the skin fibroblasts of scleroderma and look into its underlying anti-fibrotic mechanisms.

METHODS

Bleomycin was used to establish the SSc mouse model. After TAN IIA treatment, dermal thickness, type I collagen and hydroxyproline content were measured. Primary fibroblasts were acquired from SSc patients and cultured in vitro, and the effects of TAN IIA on proliferation, apoptosis and the cell cycle of fibroblasts were detected.

RESULTS

In a bleomycin-induced SSc model, we discovered that TAN IIA significantly improved skin thickness and collagen deposition, demonstrating a potent anti-fibrotic action. TAN IIA inhibits the proliferation of skin fibroblasts derived from SSc patients by causing G2/M cell cycle arrest and promoting apoptosis. Additionally, TAN IIA downregulated extracellular matrix gene transcription and collagen protein expression in skin fibroblasts in a dose-gradient-dependent manner. Furthermore, we showed how TAN IIA can reduce the activation of the transforming growth factor-β (TGF-β)/Smad and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathways, which are important factors in SSc.

CONCLUSIONS

In summary, these data suggest that TAN IIA can reduce SSc-related skin fibrosis by modulating the TGF-β/Smad and MAPK/ERK signalling pathways. More importantly, our results imply that TAN IIA can directly act on the skin fibroblasts of SSc, therefore, inhibiting fibrosis.

Salvianolic acid B protects against pulmonary fibrosis by attenuating stimulating protein 1-mediated macrophage and alveolar type 2 cell senescence

Idiopathic pulmonary fibrosis (IPF), as the most common idiopathic interstitial pneumonia, is caused by a complex interaction of pathological mechanisms. Interestingly, IPF frequently occurs in the middle-aged and elderly populations but rarely affects young people. Salvianolic acid B (SAB) exerts antioxidant, antiinflammatory, and antifibrotic bioactivities and is considered a promising drug for pulmonary disease treatment. However, the pharmacological effects and mechanisms of SAB on cellular senescence of lung cells and IPF development remain unclear. We used bleomycin (BLM)-induced pulmonary fibrosis mice and different lung cells to investigate the antisenescence impact of SAB and explain its underlying mechanism by network pharmacology and the Human Protein Atlas database. Here, we found that SAB significantly prevented pulmonary fibrosis and cellular senescence in mice, and reversed the senescence trend and typical senescence-associated secretory phenotype (SASP) factors released from lung macrophages and alveolar type II (AT2) epithelial cells, which further reduced lung fibroblasts activation. Additionally, SAB alleviated the epithelial-mesenchymal transition process of AT2 cells induced by transforming growth factor beta. By predicting potential targets of SAB that were then confirmed by chromatin immunoprecipitation-qPCR technology, we determined that SAB directly hampered the binding of transcription factor stimulating protein 1 to the promoters of SASPs (P21 and P16), thus halting lung cell senescence. We demonstrated that SAB reduced BLM-induced AT2 and macrophage senescence, and the subsequent release of SASP factors that activated lung fibroblasts, thereby dual-relieving IPF. This study provides a new scientific foundation and perspective for pulmonary fibrosis therapy.

Salvianolic acid B-loaded polydopamine-modified hollow mesoporous organic silica nanoparticles for treatment of breast cancer metastasis via suppressing cancer-associated fibroblasts

OBJECTIVE

Drug Delivery System was constructed using dopamine-coated organic-inorganic hybrid hollow mesoporous organic silica nanoparticles (HMON-PDA) as drug carriers and salvianolic acid B (SAB) as a model drug. Then, we further investigated whether it can inhibit lung metastasis of breast cancer by inhibiting cancer-associated fibroblasts (CAFs).

METHODS

The organic-inorganic hybrid hollow mesoporous organic silica nanoparticles (HMON) were prepared. The particle size, zeta potential, and polydispersion coefficient were characterized. High-performance liquid chromatography was used to determine the effect of different feed ratios of HMON and SAB on drug loading rate. Then, SAB-loaded HMON were modified by polydopamine, which is called SAB@HMON-PDA. Cell viability was detected by MTT assay. The migration of 4T1 cells was investigated by wound healing experiment, and the invasion of 4T1 cells was detected by the transwell method. Finally, the mouse breast cancer lung metastasis models were used to explore whether SAB@HMON-PDA can inhibit lung metastasis of breast cancer by inhibiting CAFs.

RESULTS

The obtained nanoparticles have hollow spherical structure. The average particle sizes of HMON, SAB@HMON, and SAB@HMON-PDA were 143.5 ± 0.03, 138.3 ± 0.02, and 172.3 ± 0.18 nm, respectively. The zeta potentials were -44.33±0.15, -41.4 ± 1.30, and -24.13±0.47 mV, respectively. When the ratio of HMON to SAB was 2:1, the drug loading rate reached (18.37±0.04)%. In addition, the prepared SAB@HMON-PDA responded to release SAB under acidic and GSH conditions. The prepared SAB@HMON-PDA could inhibit the migration and invasion of 4T1 cells. The results showed that SAB@HMON-PDA and SAB could inhibit lung metastasis of breast cancer in mice, and SAB@HMON-PDA had a more significant inhibitory effect than SAB.

CONCLUSION

We successfully prepared SAB@HMON-PDA with the dual response of pH and GSH. SAB@HMON-PDA can inhibit the migration and invasion of 4T1 cells, and the effect is more significant than free SAB. This inhibitory effect may be related to the inhibition of CAFs. In vivo experiments demonstrated that SAB@HMON-PDA can inhibit lung metastasis of breast cancer by inhibiting CAFs, and its effect was more significant than that of free SAB.

PAI-1 mediates TGF-β1-induced myofibroblast activation in tenocytes via mTOR signaling

Transforming growth factor-beta (TGF-β1) induces plasminogen activator inhibitor 1 (PAI-1) to effect fibrotic pathologies in several organs including tendon. Recent data implicated PAI-1 with inhibition of phosphatase and tensin homolog (PTEN) suggesting that PAI-1-induced adhesions involves phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (mTOR) signaling. Ergo, we investigated effects of TGF-β1, PAI-1, and mTOR signaling crosstalk on myofibroblast activation, senescence, and proliferation in primary flexor tenocytes from wild-type (WT) and PAI-1 knockout (KO) mice. PAI-1 deletion blunted TGF-β1-induced myofibroblast activation in murine flexor tenocytes and increased the gene expression of Mmp-2 to confer protective effects against fibrosis. While TGF-β1 significantly reduced phosphorylation of PTEN in WT cells, PAI-1 deletion rescued the activation of PTEN. Despite that, there were no differences in TGF-β1-induced activation of mTOR signaling (AKT, 4EBP1, and P70S6K) in WT or KO tenocytes. Phenotypic changes in distinct populations of WT or KO tenocytes exhibiting high or low mTOR activity were then examined. TGF-β1 increased alpha-smooth muscle actin abundance in WT cells exhibiting high mTOR activity, but this increase was blunted in KO cells exhibiting high 4EBP1 activity but not in cells exhibiting high S6 activity. DNA damage (γH2AX) was increased with TGF-β1 treatment in WT tenocytes but was blunted in KO cells exhibiting high mTOR activity. Increased mTOR activity enhanced proliferation (Ki67) in both WT and KO tenocytes. These findings point to a complex nexus of TGF-β1, PAI-1, and mTOR signaling in regulating proliferation, myofibroblast differentiation, and senescence in tenocytes, which could define therapeutic targets for chronic tendon adhesions and other fibrotic pathologies.

GRB2 serves as a viable target against skin fibrosis in systemic sclerosis by regulating endothelial cell apoptosis

BACKGROUND

Systemic Sclerosis (SSc) is an autoimmune disease characterized by vascular and immune system dysfunction, along with tissue fibrosis. Our previous study found GRB2 was downregulated by salvianolic acid B, a small molecule drug that attenuated skin fibrosis of SSc.

OBJECTIVES

Here we aim to investigate the role of GRB2 in SSc.

METHODS

The microarray data of SSc skin biopsies in Caucasians were obtained from the Gene Expression Omnibus (GEO) database. The expression of GRB2 was further detected in Chinese SSc and healthy controls. Bleomycin (BLM)-induced skin fibrosis mice were used to explore how GRB2 downregulation affected fibrosis. The apoptosis of EA.hy926 endothelial cells was induced by H2O2 and apoptosis ratio was measured by flow cytometric. Transcriptome and phosphoproteomic analyses were performed to explore the regulated pathway.

RESULTS

The expression of GRB2 was significantly enhanced in SSc patient skin, 1.51-fold in Caucasians and 1.40-fold in Chinese. Double immunofluorescence staining showed the endothelial cells of SSc patient's skin highly expressed GRB2. The in vivo study revealed that GRB2 knockdown alleviated skin fibrosis and apoptosis of endothelial cells in BLM mouse skin. The in vitro study showed that GRB2 downregulation inhibited the apoptosis of EA.hy926 and protected them from H2O2-induced hyperpermeability. Moreover, transcriptome and phosphoproteomic analysis suggested the focal adhesion pathway was enriched in GRB2 siRNA transfected endothelial cells.

CONCLUSIONS

Our results demonstrated GRB2 highly expressed in endothelial cells of SSc skin, and inhibiting GRB2 could effectively attenuate BLM-induced skin fibrosis and endothelial cell apoptosis. GRB2 is expected to be a new therapeutic target for SSc.

Salvianolic Acid B Attenuates Hypertrophic Scar Formation In Vivo and In Vitro

BACKGROUND

Hypertrophic scars (HTSs) are a fibroproliferative disorder that occur following skin injuries. Salvianolic acid B (Sal-B) is an extractant from Salvia miltiorrhiza that has been reported to ameliorate fibrosis in multiple organs. However, the antifibrotic effect on HTSs remains unclear. This study aimed to determine the antifibrotic effect of Sal-B in vitro and in vivo.

METHODS

In vitro, hypertrophic scar-derived fibroblasts (HSFs) were isolated from human HTSs and cultured. HSFs were treated with (0, 10, 50, 100 μmol/L) Sal-B. Cell proliferation and migration were evaluated by EdU, wound healing, and transwell assays. The protein and mRNA levels of TGFβI, Smad2, Smad3, α-SMA, COL1, and COL3 were detected by Western blots and real-time PCR. In vivo, tension stretching devices were fixed on incisions for HTS formation. The induced scars were treated with 100 μL of Sal-B/PBS per day according to the concentration of the group and followed up for 7 or 14 days. The scar condition, collagen deposition, and α-SMA expression were analyzed by gross visual examination, H&E, Masson, picrosirius red staining, and immunofluorescence.

RESULTS

In vitro, Sal-B inhibited HSF proliferation, migration, and downregulated the expression of TGFβI, Smad2, Smad3, α-SMA, COL1, and COL3 in HSFs. In vivo, 50 and 100 μmol/L Sal-B significantly reduced scar size in gross and cross-sectional observations, with decreased α-SMA expression and collagen deposition in the tension-induced HTS model.

CONCLUSIONS

Our study demonstrated that Sal-B inhibits HSFs proliferation, migration, fibrotic marker expression and attenuates HTS formation in a tension-induced HTS model in vivo.

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2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside ameliorates bleomycin-induced pulmonary fibrosis via regulating pro-fibrotic signaling pathways

2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-Glucoside (THSG) is the main active ingredient extracted from Polygonum multiflorum Thunb. (PMT), which has been reported to possess extensive pharmacological properties. Nevertheless, the exact role of THSG in pulmonary fibrosis has not been demonstrated yet. The main purpose of this study was to investigate the protective effect of THSG against bleomycin (BLM)-induced lung fibrosis in a murine model, and explore the underlying mechanisms of THSG in transforming growth factor-beta 1 (TGF-β1)-induced fibrogenesis using MRC-5 human lung fibroblast cells. We found that THSG significantly attenuated lung injury by reducing fibrosis and extracellular matrix deposition. THSG treatment significantly downregulated the expression levels of TGF-β1, fibronectin, α-SMA, CTGF, and TGFBR2, however, upregulated the expression levels of antioxidants (SOD-1 and catalase) and LC3B in the lungs of BLM-treated mice. THSG treatment decreased the expression levels of fibronectin, α-SMA, and CTGF in TGF-β1-stimulated MRC-5 cells. Conversely, THSG increased the expression levels of SOD-1 and catalase. Furthermore, treatment of THSG profoundly reduced the TGF-β1-induced generation of reactive oxygen species (ROS). In addition, THSG restored TGF-β1-induced impaired autophagy, accompany by increasing the protein levels of LC3B-II and Beclin 1. Mechanism study indicated that THSG significantly reduced TGF-β1-induced increase of TGFBR2 expression and phosphorylation of Smad2/3, Akt, mTOR, and ERK1/2 in MRC-5 cells. These findings suggest that THSG may be considered as an anti-fibrotic drug for the treatment of pulmonary fibrosis.

Salvia miltiorrhiza in thorax and abdomainal organ fibrosis: A review of its pharmacology

Organ fibrosis is a common pathological change that finally results in organ failure, which involves the destruction of parenchyma cells, the activation of mesenchymal cells and the imbalance of immunological cells. In recent years, although some breakthroughs have been made in understanding the pathogenesis and therapeutics of organ fibrosis, no registered drugs could directly target the fibrotic process, which constitutes a major biomedical challenge. Salvia miltiorrhiza (SM) is a well-known medicinal plant in China, which has been widely applied because of its pharmacological effects on anti-oxidative, anti-myocardial infarction, anti-fibrotic, anti-inflammatory, and anti-neoplastic properties. Accumulated evidence suggested that SM played critical roles against organ fibrosis in vivo and in vitro experiments by its multiple biological compounds. In this review, we discussed the recent advances on the phytochemistry and pharmacological mechanisms of SM and its active ingredients in liver, lung, kidney, and heart fibrosis, which might help to promote the treatment of fibrotic diseases in thorax and abdomainal viscera in clinic.

Therapeutic Effects of Salvianolic Acid B on Angiotensin II-Induced Atrial Fibrosis by Regulating Atrium Metabolism via Targeting AMPK/FoxO1/miR-148a-3p Axis

The present study highlights the effects of salvianolic acid B (Sal B) on angiotensin II (Ang II)-activated atrial fibroblasts as well as the associated potential mechanism from the metabonomics perspective. Metabolic profile analysis performed an optimal separation of the Ang II and control group, indicating a recovery impact of Sal B on Ang II-activated fibroblasts (FBs). We found that metabolite levels in the Ang II + Sal B group were reversed to normal. Moreover, 23 significant metabolites were identified. Metabolic network analysis indicated that these metabolites participated in purine metabolism and FoxO signaling pathway. We found that Sal B activated AMP-activated protein kinase (AMPK) phosphorylation, which further promoted FoxO1 activation and increased miR-148a-3p level. We further verified that Sal B modulate the abnormal AMP, phosphocreatine, glutathione (GSH), and reactive oxygen species (ROS) production in Ang II-stimulated FBs. Collectively, Sal B can protect the Ang II-activated FBs from fibrosis and oxidative stress via AMPK/FoxO1/miRNA-148a-3p axis.

Salvianolic acid B inhibits autophagy and activation of hepatic stellate cells induced by TGF-β1 by downregulating the MAPK pathway

In liver fibrosis, transforming growth factor-β1 (TGF-β1) can stimulate autophagy and activation of hepatic stellate cells (HSCs). Autophagy, playing a crucial role in HSCs activation, is related to liver fibrosis. Increasing evidence have suggested that antifibrosis effects of salvianolic acid B (Sal B) and their mechanisms of action, however, remain unclear. The aim of the article is to understand the role of Sal B in HSCs autophagy in liver fibrosis. Herein, we demonstrated that inducing TGF-β1 led to dramatic increase in autophagosome formation and autophagic flux in JS1 and LX2, which was mediated through the ERK, JNK, and p38 MAPK cascades. TGF-β1 significantly increased the protein of autophagy and liver fibrosis, including LC3BⅡ, ATG5, α-SMA, and Col.I; Sal B inhibits JS1 autophagy and activation by inhibiting the formation of autophagosomes and autophagic flux. Sal B significantly decreased the LC3BⅡ, ATG5, α-SMA, and Col.I protein expressions; pretreatment with autophagy inhibitors, chloroquine (CQ) and 3-methyladenine (3-MA) or silencing ATG7 further increase these reductions. However, pretreatment with autophagy agonist, rapamycin (Rapa), or overexpressed ATG5 attenuated this decrease. To further assess the importance of this mechanism, the antibody chip was used to detect the change of phosphorylation protein expression of the MAPK signaling pathway after treating JS1 with Sal B. Eleven differentially expressed proteins were verified. Sal B inhibits activation and autophagy of JS1 induced by TGF-β1 through downregulating the ERK, p38, and JNK signaling pathways, as demonstrated by downregulating p-ERK, p-JNK, and p-p38 MAPK protein expressions. In conclusion, Sal B inhibits autophagy and activation induced by TGF-β1 of HSCs possibly by downregulating the MAPK pathway.

Polyphenols from Chinese Herbal Medicine: Molecular Mechanisms and Therapeutic Targets in Pulmonary Fibrosis

Pulmonary fibrosis (PF) is a highly confounding and fatal pathological process with finite treatment options. Multiple factors such as oxidative and immune/inflammation involve key pathological processes in chronic lung disease, and their intimate interactions mediate chronic lung damage, denudation of the alveolar epithelium, hyperproliferation of type II alveolar epithelial cells (AECIIs), proliferation and differentiation of fibroblasts, and the permeability of microvessels. We reviewed the classic mechanism of PF and highlighted a few emerging mechanisms for studying complex networks in lung disease pathology. Polyphenols, as a multi-target drug, has excellent potential in the treatment of pulmonary fibrosis. We then reviewed recent advances in discovering phenolic compounds from fruits, tea, and medical herbs with the bioactivities of simultaneously regulating multiple factors (e.g., oxidative stress, inflammation, autophagy, apoptosis, pyroptosis) for minimizing pulmonary fibrosis injury. These compounds include resveratrol, curcumin, salvianolic acid B, epigallocatechin-3-gallate, gallic acid, corilagin. Each phenolic compound can exert its anti-PF effect through various mechanisms, and the signaling pathways involved in different phenolic compounds are not the same. This review summarized the available evidence on phenolic compounds' effectiveness in pulmonary diseases and explored the molecular mechanisms and therapeutic targets of phenolic compounds from Chinese herbal medicine with the properties of inhibition of ongoing fibrogenesis and resolution of existing fibrosis.

An Overview of Herbal Medicines for Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung scarring condition with the histological characteristic of typical interstitial pneumonia. Injury to alveolar epithelial cells is a critical precursor in the pathogenesis of this disease. The prevalence of IPF is growing exponentially, with substantial morbidity and mortality rates increasing the burden on economic healthcare costs. A multidisciplinary approach for diagnosis is used to rule out the alternative causes of interstitial lung disease. Pirfenidone and nintedanib, two innovative antifibrotic medicines introduced in recent years, have provided therapeutic benefits to many IPF patients, and several IPF medications are in the early phases of clinical trials. However, available medications can cause unpleasant symptoms such as nausea and diarrhoea. More efforts have been made to uncover alternative treatments towards a more personalised patient-centred care and hence improve the outcomes in the IPF patients. Through a multi-level and multi-target treatment approach, herbal medicines, such as Traditional Chinese Medicine (TCM), have been identified as revolutionary medical treatment for IPF. Due to their natural properties, herbal medicines have shown to possess low adverse effects, stable therapeutic impact, and no obvious drug dependencies. Herbal medicines have also shown anti-inflammatory and anti-fibrotic effects, which make them a promising therapeutic target for IPF. A growing number of formulas, herbal components, and various forms of Chinese herbal medicine extracts are available for IPF patients in China. This review summarises the role of herbal medicines in the prevention and treatment of IPF.

Screening and evaluation of quality markers from Shuangshen Pingfei formula for idiopathic pulmonary fibrosis using network pharmacology and pharmacodynamic, phytochemical, and pharmacokinetic analyses

BACKGROUND

The Shuangshen Pingfei formula (SSPF), a classic Chinese medicine derivative formula, has been shown to exert therapeutic effects on idiopathic pulmonary fibrosis (IPF). However, the quality control compounds of SSPF remain unclear.

PURPOSE

To select and confirm Q-markers of SSPF based on network pharmacology, cytobiology, animal-based pharmacodynamics, and phytochemical and pharmacokinetic analyses.

METHODS

A compound-target network was constructed based on previous research. In addition, high-degree compounds of SSPF were chosen as potential Q-marker candidates. Animal and cytological experiments were performed to verify key targets of IPF. Haematoxylin-eosin and Masson's trichrome staining were used to observe lung tissue pathology. Cytokine levels in the bronchoalveolar lavage fluid (BALF) were measured using ELISA kits. Gene and protein expression levels were determined using PCR and western blotting, respectively. The contents of Q-marker candidates in different batches of SSPF were then determined for traceability research, and the quality consistency of SSPF was objectively evaluated using principal component analysis (PCA). Finally, pharmacokinetic research was performed, and candidates with desirable metabolite and bioavailability parameters were confirmed as Q-markers of SSPF.

RESULTS

The compound-target network included 56 compounds and 14 therapeutic targets. Animal experiments showed that SSPF attenuates lung fibrosis. SSPF decreased CC motif chemokine 2 (CCL2) and CC chemokine receptor type 2 (CCR2) levels in the BALF and downregulated the gene and protein expression of IPF therapy-related molecules, such as 5-hydroxytryptamine receptor 2A (HTR2A), CCL2, and CCR2, in the lungs. Cell experiments showed that nine Q-marker candidates in SSPF regulated the expression of CCL2 and CCR2, as predicted. Phytochemical analysis and PCA indicated that the qualities of SSPF in the nine batches were relatively stable. Pharmacokinetic studies demonstrated that mangiferin, salvianolic acid B, tanshinone IIA, naringin, and glycyrrhizic acid could be effectively absorbed into rat plasma, which ensured desirable bioavailability and confirmed their roles as Q-markers to represent anti-pulmonary fibrotic activity.

CONCLUSION

Our study is an integrated strategy, based on network pharmacology with experimental verification and phytochemical and pharmacokinetic analyses that provides a novel approach for Q-marker selection and validation of SSPF for IPF treatment.

The Roles of Noncoding RNAs in Systemic Sclerosis

Noncoding RNAs (ncRNAs) constitute more than 90% of the RNAs in the human genome. In the past decades, studies have changed our perception of ncRNAs from “junk” transcriptional products to functional regulatory molecules that mediate critical processes, including chromosomal modifications, mRNA splicing and stability, and translation, as well as key signaling pathways. Emerging evidence suggests that ncRNAs are abnormally expressed in not only cancer but also autoimmune diseases, such as systemic sclerosis (SSc), and may serve as novel biomarkers and therapeutic targets for the diagnosis and treatment of SSc. However, the functions and underlying mechanisms of ncRNAs in SSc remain incompletely understood. In this review, we discuss the current findings on the biogenetic processes and functions of ncRNAs, including microRNAs and long noncoding RNAs, as well as explore emerging ncRNA-based diagnostics and therapies for SSc.

Salvianolic acid B acts against non‑small cell lung cancer A549 cells via inactivation of the MAPK and Smad2/3 signaling pathways

Salvianolic acid B (Sal B) is a potential cytotoxic polyphenol against cancer. In the present study the effect of Sal B and its molecular mechanism were investigated in the non‑small cell lung cancer (NSCLC) A549 cell line. The TGF‑β/MAPK/Smad signaling axis was explored. A549 cells were co‑cultured with and without different concentrations of Sal B (25, 50 and 100 µM respectively) and TGF‑β1 (9 pM) for 24 h. Cell epithelial‑mesenchymal transition (EMT), cell migration, cell cycle distribution, autophagy and apoptosis were assessed by western blotting (WB), wound healing assay and flow cytometry, respectively. Moreover, activation of MAPK, Smad2/3 and the downstream target, plasminogen activator inhibitor 1 (PAI‑1), were assessed by WB. The results demonstrated that Sal B inhibited TGF‑β1‑induced EMT and migration of A549 cells, hampered cell cycle progression and induced cell autophagy and apoptosis. Furthermore, Sal B inactivated MAPK signaling pathways and the phosphorylation of Smad2/3, especially the phosphorylation of Smad3 at the linker region, which resulted in decreased protein expression levels of PAI‑1 in TGF‑β1‑stimulated A549 cells. Overall, these results demonstrated that Sal B may have a potential therapeutic effect against NSCLC in vitro. The results of the present study indicated that the underlying active mechanism of Sal B in NSCLC may be closely related to the impeded activation of the MAPK and Smad2/3 signaling pathways. Therefore, Sal B may be a potential candidate NSCLC therapeutic agent.

Natural Product-Based Potential Therapeutic Interventions of Pulmonary Fibrosis

Pulmonary fibrosis (PF) is a disease-refractive lung condition with an increased rate of mortality. The potential factors causing PF include viral infections, radiation exposure, and toxic airborne chemicals. Idiopathic PF (IPF) is related to pneumonia affecting the elderly and is characterized by recurring scar formation in the lungs. An impaired wound healing process, defined by the dysregulated aggregation of extracellular matrix components, triggers fibrotic scar formation in the lungs. The potential pathogenesis includes oxidative stress, altered cell signaling, inflammation, etc. Nintedanib and pirfenidone have been approved with a conditional endorsement for the management of IPF. In addition, natural product-based treatment strategies have shown promising results in treating PF. In this study, we reviewed the recently published literature and discussed the potential uses of natural products, classified into three types-isolated active compounds, crude extracts of plants, and traditional medicine, consisting of mixtures of different plant products-in treating PF. These natural products are promising in the treatment of PF via inhibiting inflammation, oxidative stress, and endothelial mesenchymal transition, as well as affecting TGF-β-mediated cell signaling, etc. Based on the current review, we have revealed the signaling mechanisms of PF pathogenesis and the potential opportunities offered by natural product-based medicine in treating PF.

Wenfei Buqi Tongluo Formula Against Bleomycin-Induced Pulmonary Fibrosis by Inhibiting TGF-β/Smad3 Pathway

Pulmonary fibrosis (PF) is the end stage of various chronic and progressive interstitial lung diseases. TGF-β, a profibrotic cytokine, can promote epithelial–mesenchymal transition (EMT), extracellular matrix (ECM) accumulation, and fibroblast proliferation, which contribute to progressive lung remodeling in PF. The Wenfei Buqi Tongluo (WBT) formula has been certified to be effective in the prevention and treatment of PF in clinical practice and has inhibitory effects on EMT, inflammation, and profibrotic factors. However, the pharmacological mechanisms of WBT against PF need to be further explored. In this study, we first analyzed the chemical components of the WBT formula using the UHPLC/Q-TOF-MS analysis. The potential targets of the identified compounds from WBT were predicted by the network pharmacology, which was confirmed by in vivo and in vitro study. After screening by the PubChem database, we first identified the 36 compounds of WBT and predicted the TGF-β signaling pathway, with ECM degradation as potential mechanism of WBT against PF by the network pharmacology. Furthermore, WBT treatment inhibited the levels of TGF-β and Smad3 phosphorylation and subsequently alleviated EMT and ECM accumulation in the bleomycin-induced mouse model and TGF-β1–induced cell model. These findings indicate that WBT can block the progressive process of PF by inhibiting EMT and promoting ECM degradation via the TGF-β/Smad3 pathway. This study may provide new insights into the molecular mechanism of WBT for the prevention and treatment of PF in the clinical application.

Xuanfei Baidu Decoction protects against macrophages induced inflammation and pulmonary fibrosis via inhibiting IL-6/STAT3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Xuanfei Baidu Decoction (XFBD), one of the "three medicines and three prescriptions" for the clinically effective treatment of COVID-19 in China, plays an important role in the treatment of mild and/or common patients with dampness-toxin obstructing lung syndrome.

AIM OF THE STUDY

The present work aims to elucidate the protective effects and the possible mechanism of XFBD against the acute inflammation and pulmonary fibrosis.

METHODS

We use TGF-β1 induced fibroblast activation model and LPS/IL-4 induced macrophage inflammation model as in vitro cell models. The mice model of lung fibrosis was induced by BLM via endotracheal drip, and then XFBD (4.6 g/kg, 9.2 g/kg) were administered orally respectively. The efficacy and molecular mechanisms in the presence or absence of XFBD were investigated.

RESULTS

The results proved that XFBD can effectively inhibit fibroblast collagen deposition, down-regulate the level of α-SMA and inhibit the migration of fibroblasts. IL-4 induced macrophage polarization was also inhibited and the secretions of the inflammatory factors including IL6, iNOS were down-regulated. In vivo experiments, the results proved that XFBD improved the weight loss and survival rate of the mice. The XFBD high-dose administration group had a significant effect in inhibiting collagen deposition and the expression of α-SMA in the lungs of mice. XFBD can reduce bleomycin-induced pulmonary fibrosis by inhibiting IL-6/STAT3 activation and related macrophage infiltration.

CONCLUSIONS

Xuanfei Baidu Decoction protects against macrophages induced inflammation and pulmonary fibrosis via inhibiting IL-6/STAT3 signaling pathway.

Targeting Oxidative Stress as a Therapeutic Approach for Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease characterized by an abnormal reepithelialisation, an excessive tissue remodelling and a progressive fibrosis within the alveolar wall that are not due to infection or cancer. Oxidative stress has been proposed as a key molecular process in pulmonary fibrosis development and different components of the redox system are altered in the cellular actors participating in lung fibrosis. To this respect, several activators of the antioxidant machinery and inhibitors of the oxidant species and pathways have been assayed in preclinical in vitro and in vivo models and in different clinical trials. This review discusses the role of oxidative stress in the development and progression of IPF and its underlying mechanisms as well as the evidence of oxidative stress in human IPF. Finally, we analyze the mechanism of action, the efficacy and the current status of different drugs developed to inhibit the oxidative stress as anti-fibrotic therapy in IPF.

JUN promotes hypertrophic skin scarring via CD36 in preclinical in vitro and in vivo models

[Figure: see text].

Evaluation of Wound Healing Activity of Salvianolic Acid B on In Vitro Experimental Model

Despite a wide range of bactericides and antiseptics, the treatment of chronic or complicated wounds is still a major challenge for modern medicine. Topical medications are the most sought-after new agents for use as treatment. The therapeutic concentration of their active substances is easy to achieve with the lowest possible burden on the patient’s body. This study assesses the effect of salvianolic acid B (Sal B) on the proliferation, migration, and production of collagen type III by fibroblasts, which are the most important processes in wound healing. The study was conducted on human gingival fibroblasts obtained from primary cell culture. The results showed that Sal B at a dose of 75 µg/mL increases the cell viability with significant stimulation of the cell migration as demonstrated in the wound healing assay, as well as an increase in the expression of collagen type III, which has great importance in the initial stages of wound scarring. The results obtained in the conducted studies and previous scientific reports on the antibacterial properties and low toxicity of Sal B indicate its high potential in wound healing.

The role of natural products in the prevention and treatment of pulmonary fibrosis: a review

Pulmonary fibrosis is an incurable end-stage lung disease and remains a global public health problem. Although there have been some breakthroughs in understanding the pathogenesis of pulmonary fibrosis, effective intervention methods are still limited. Natural products have the advantages of multiple biological activities and high levels of safety, which are important factors for preventing and treating pulmonary fibrosis. In this review, we summarized the mechanisms and health benefits of natural products against pulmonary fibrosis. These natural products target oxidative stress, inflammatory injury, epithelial-mesenchymal transition (EMT), fibroblast activation, extracellular matrix accumulation and metabolic regulation, and the mechanisms involve the NF-κB, TGF-β1/Smad, PI3K/Akt, p38 MAPK, Nrf2-Nox4, and AMPK signaling pathways. We hope to provide new ideas for pulmonary fibrosis prevention and treatment strategies.

Anti-Fibrosis Effects of Magnesium Lithospermate B in Experimental Pulmonary Fibrosis: By Inhibiting TGF-βRI/Smad Signaling

Pulmonary fibrosis is a severe and irreversible interstitial pulmonary disease with high mortality and few treatments. Magnesium lithospermate B (MLB) is a hydrosoluble component of Salvia miltiorrhiza and has been reported to have antifibrotic effects in other forms of tissue fibrosis. In this research, we studied the effects of MLB on pulmonary fibrosis and the underlying mechanisms. Our results indicated that MLB treatment (50 mg/kg) for seven days could attenuate bleomycin (BLM)-induced pulmonary fibrosis by reducing the alveolar structure disruption and collagen deposition in the C57 mouse model. MLB was also found to inhibit transforming growth factor-beta (TGF-β)-stimulated myofibroblastic transdifferentiation of human lung fibroblast cell line (MRC-5) cells and collagen production by human type II alveolar epithelial cell line (A549) cells, mainly by decreasing the expression of TGF-β receptor I (TGF-βRI) and regulating the TGF-β/Smad pathway. Further studies confirmed that the molecular mechanisms of MLB in BLM-induced pulmonary fibrosis mice were similar to those observed in vitro. In summary, our results demonstrated that MLB could alleviate experimental pulmonary fibrosis both in vivo and in vitro, suggesting that MLB has great potential for pulmonary fibrosis treatment.

Traditional Chinese medicine combined with pulmonary drug delivery system and idiopathic pulmonary fibrosis: Rationale and therapeutic potential

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Pathogenesis and characteristics of idiopathic pulmonary fibrosis (IPF) are presented.

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The history and current situation of traditional Chinese medicine (TCM) in treating lung diseases are introduced.

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Therapeutic mechanisms of different TCM to treat IPF are summarized.

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Advantages and types of pulmonary drug delivery systems (PDDS) are emphasized.

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Combining TCM with PDDS is a potential strategy to treat IPF.

Idiopathic pulmonary fibrosis (IPF) is a progressive pulmonary interstitial inflammatory disease of unknown etiology, and is also a sequela in severe patients with the Coronavirus Disease 2019 (COVID-19). Nintedanib and pirfenidone are the only two known drugs which are conditionally recommended for the treatment of IPF by the FDA. However, these drugs pose some adverse side effects such as nausea and diarrhoea during clinical applications. Therefore, it is of great value and significance to identify effective and safe therapeutic drugs to solve the clinical problems associated with intake of western medicine. As a unique medical treatment, Traditional Chinese Medicine (TCM) has gradually exerted its advantages in the treatment of IPF worldwide through a multi-level and multi-target approach. Further, to overcome the current clinical problems of oral and injectable intakes of TCM, pulmonary drug delivery system (PDDS) could be designed to reduce the systemic metabolism and adverse reactions of the drug and to improve the bioavailability of drugs. Through PubMed, Google Scholar, Web of Science, and CNKI, we retrieved articles published in related fields in recent years, and this paper has summarized twenty-seven Chinese compound prescriptions, ten single TCM, and ten active ingredients for effective prevention and treatment of IPF. We also introduce three kinds of inhaling PDDS, which supports further research of TCM combined with PDDS to treat IPF.

Inhibiting TGF-[Formula: see text] 1-Mediated Cellular Processes as an Effective Strategy for the Treatment of Pulmonary Fibrosis with Chinese Herbal Medicines

Pulmonary fibrosis (PF) is a chronic and irreversible interstitial lung disease that even threatens the lives of some patients infected with COVID-19. PF is a multicellular pathological process, including the initial injuries of epithelial cells, recruitment of inflammatory cells, epithelial-mesenchymal transition, activation and differentiation of fibroblasts, etc. TGF-[Formula: see text]1 acts as a key effect factor that participates in these cellular processes of PF. Recently, much attention was paid to inhibiting TGF-[Formula: see text]1 mediated cell processes in the treatment of PF with Chinese herbal medicines (CHM), an important part of traditional Chinese medicine. Here, this review first summarized the effects of TGF-[Formula: see text]1 in different cellular processes of PF. Then, this review summarized the recent research on CHM (compounds, multi-components, single medicines and prescriptions) to directly and/or indirectly inhibit TGF-[Formula: see text]1 signaling (TLRs, PPARs, micrRNA, etc.) in PF. Most of the research focused on CHM natural compounds, including but not limited to alkaloids, flavonoids, phenols and terpenes. After review, the research perspectives of CHM on TGF-[Formula: see text]1 inhibition in PF were further discussed. This review hopes that revealing the inhibiting effects of CHM on TGF-[Formula: see text]1-mediated cellular processes of PF can promote CHM to be better understood and utilized, thus transforming the therapeutic activities of CHM into practice.

[Expression of pituitary tumor-transforming gene-1 and its pathogenic role in systemic sclerosis]

OBJECTIVE

To investigate the expression of tumor-transforming gene-1 (PTTG1) in systemic sclerosis (SSc) and its role in fibrosis.

METHODS

Skin biopsy samples were collected from 21 patients with SSc and 22 patients with healthy skin for detecting the mRNA and protein expressions of PTTG1 using real-time PCR (RT-PCR) and immunohistochemistry, respectively. In cultured primary human dermal fibroblasts, PTTG1 expression was knocked down via RNA interference (siRNA), and the mRNA expression levels of PTTG1 and the fibrosis-related genes α-SMA, COL1A1, COL1A2, and COL3A1 were detected using RT-PCR; the proliferation of the cells was assessed using a real-time cell proliferation detection system.

RESULTS

Compared with those in normal skin samples, the mRNA and protein expressions of PTTG1 increased significantly in the skin tissue of patients with SSc (P < 0.05). In cultured primary skin fibroblasts, the expression of PTTG1 mRNA was positively correlated with those of α-SMA (R²=0.8192, P < 0.05), COL1A1 (R²=0.6398, P < 0.05), COL1A2 (R²=0.316, P < 0.05) and COL3A1 mRNAs (R²=0.3727, P < 0.05). Interference of PTTG1 expression significantly inhibited the cell proliferation, obviously lowered the expressions of fibrosis-related genes, and down-regulated the expression of collagen in the fibroblasts.

CONCLUSIONS

PTTG1 is highly expressed in skin tissues of patients with SSc, and PTTG1 knockdown can reduce the activity of the dermal fibroblasts, suggesting a close correlation of PTTG1 with fibrosis in SSc.

A dry powder inhalable formulation of salvianolic acids for the treatment of pulmonary fibrosis: safety, lung deposition, and pharmacokinetic study

Salvianolic acids (SAL), the main bioactive component extracted from Salvia miltiorrhiza, is a natural product with a reported anti-pulmonary fibrosis (PF) effect. SAL is commonly administrated orally; however, it has a low oral bioavailability (less than 5%). The objective of this work was to develop a new dry powder inhalable formulation intended to facilitate the access of SAL to the target place. We prepared the new SAL powder formulation containing L-arginine and 2% of lecithin using the ball milling technique. L-arginine was used to regulate the strong acidity of the SAL solution, and lecithin was added to disperse the powder and improve the flowability. The resulting powder had a content in salvianolic acid B (SALB, the main active principle of SAL) of 66.67%, a particle size of less than 5 μm and a good flowability. In vivo fluorescence imaging showed that the powder could be successfully aerosolized and delivered to the lung. The acute lung irritation study proved that the presence of L-arginine improved the biocompatibility of the powder. Finally, according to the pharmacokinetic study, the new SAL powder formulation was found to significantly increase drug concentration in the lung and the bioavailability. In conclusion, the new dry powder inhalable formulation of SAL developed in this study could be a strategy to enhance the performance of SAL at the lung level. Graphical abstract.

Involvement of Disabled-2 on skin fibrosis in systemic sclerosis

BACKGROUND

Systemic sclerosis (SSc) is a connective tissue disease characterized by inflammation and fibrosis. Our previous research found Disabled-2 (DAB2) expression was significantly downregulated by salvianolic acid B, a small molecular medicine which attenuated experimental skin fibrosis of SSc. These suggest that DAB2 plays an important role in SSc skin fibrosis, but the role of DAB2 in SSc remains unclear.

OBJECTIVES

To investigate the role of DAB2 in SSc.

METHODS

DAB2 expression level was detected in the skin and peripheral blood mononuclear cells of SSc patients. Bleomycin (BLM)-induced SSc mice and primary SSc skin fibroblasts were used to investigate the effect of DAB2 downregulation on fibrosis. RNA-seq transcriptome analysis was performed to underlie the mechanism of DAB2 in fibroblasts.

RESULTS

DAB2 expression was enhanced in SSc lesion skin and was positively correlated with fibrotic genes, such as α-SMA and PAI-1. The in vivo study revealed that DAB2 downregulation alleviated skin fibrosis, alleviating skin thickness and reducing collagen deposition, and DAB2 knockdown ameliorated the inflammatory cell infiltration. The in vitro study showed that DAB2 knockdown reduced extracellular matrix genes and proteins expression. Moreover, Transcriptome analysis revealed TGF-β and focal adhesion signaling pathways were the main downregulated pathways involved in DAB2 siRNA treated fibroblasts.

CONCLUSIONS

Taken together, our results revealed that DAB2 was increased in SSc skin, and DAB2 downregulation inhibited BLM-induced mouse skin fibrosis and SSc skin fibroblasts activation. DAB2 played an important role in the pathogenesis of SSc and DAB2 modulation may represent a potential therapeutic method for SSc.

Phlorofucofuroeckol A from Ecklonia cava ameliorates TGF-β1-induced fibrotic response of human tracheal fibroblasts via the downregulation of MAPKs and SMAD 2/3 pathways inactivated TGF-β receptor

The objective of this study was to investigate inhibitory effects of a bioactive compound isolated from Ecklonia cava on fibrotic responses to transforming growth factor-β1 (TGF-β1)-stimulated Hs680. Tr human tracheal fibroblasts and the associated mechanisms of action. Post consecutive purification, a potent bioactive compound was identified phlorofucofuroeckol A. Phlorofucofuroeckol A significantly suppressed protein expression levels of collagen type I and α-smooth muscle actin (α-SMA) on TGF-β1-stimulated Hs680. Tr human tracheal fibroblasts. Further mechanistic studies determined that phlorofucofuroeckol A suppressed the phosphorylation of p38, extracellular regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) and SMAD 2/3 in TGF-β1-stimulated Hs680. Tr human tracheal fibroblasts. Moreover, we could show that phlorofucofuroeckol A inhibits binding of TGF-β1 to its TGF-β receptor by molecular docking. Based on the results, we propose that phlorofucofuroeckol A suppresses the MAPKs and SMAD 2/3 pathways and relieves cellular fibrotic activities, thus preventing tracheal fibrosis.

Buyang Huanwu Tang inhibits cellular epithelial-to-mesenchymal transition by inhibiting TGF-β1 activation of PI3K/Akt signaling pathway in pulmonary fibrosis model in vitro

Background

Pulmonary fibrosis (PF) is a chronic and progressive interstitial lung disease. Buyang Huanwu Tang (BYHWT), a classical traditional Chinese medicine formula, has been widely utilized for the treatment of PF in China. This present study aimed to explore the mechanism of BYHWT in the treatment of PF in vitro.

Methods

TGF-β1 stimulated human alveolar epithelial A549 cells were used as in vitro model for PF. Post the treatment of BYHWT, cell viability was measured by MTT assay, and cell morphology was observed under microscope. The epithelial-to-mesenchymal transition (EMT) markers (E-cadherin, Vimentin) and collagen I (Col I) were detected by western blot, immunofluorescence staining and real-time quantitative polymerase chain reaction. With the co-administration of activators (IGF-1, SC79) and inhibitors (LY294002, MK2206), the effect of BYHWT on PI3K/Akt pathway was analyzed by western blot.

Results

BYHWT inhibited cell growth, and prevented cell morphology changed from epithelial to fibroblasts in TGF-β1 induced A549 cells. BYHWT decreased Vimentin and Col I, while increased E-cadherin at both protein and mRNA levels. Moreover, phosphorylation of PI3K (p-PI3K) and phosphorylation of Akt (p-Akt) were significantly down-regulated by BYHWT in TGF-β1 stimulated A549 cells.

Conclusion

These results indicate that BYHWT suppressed TGF-β1-induced collagen accumulation and EMT of A549 cells by inhibiting the PI3K/Akt signaling pathway. These findings suggest that BYHWT may have potential for the treatment of PF.

New therapeutic strategies for IPF: Based on the "phagocytosis-secretion-immunization" network regulation mechanism of pulmonary macrophages

Pulmonary fibrosis is a chronic and progressive interstitial lung disease of known and unknown etiology. Over the past decades, macrophages have been recognized to play a significant role in IPF pathogenesis. According to their anatomical loci, macrophages can be divided to alveolar macrophages (AMs) subtypes and interstitial macrophages subtypes (IMs) with different responsibility in the damage defense response. Depending on diverse chemokines and cytokines in local microenvironments, macrophages can be induced and polarized to either classically activated (M1) or alternatively activated (M2) phenotypes in different stages of immunity. Therefore, we hypothesize that there is a "phagocytosis-secretion-immunization" network regulation of pulmonary macrophages related to a number of chemokines and cytokines. In this paper, we summarize and discuss the role of chemokines and cytokines involved in the "phagocytosis-secretion-immunization" network regulation mechanism of pulmonary macrophages, pointing toward novel therapeutic approaches based on the network target regulation in the field. Therapeutic strategies focused on modifying the chemokines, cytokines and the network are promising for the pharmacotherapy of IPF. Some Traditional Chinese medicines may have more superiorities in delaying the progression of pulmonary fibrosis for their multi-target activities of this network regulation.

Cryptotanshinone protects against pulmonary fibrosis through inhibiting Smad and STAT3 signaling pathways

Cryptotanshinone (CTS), a lipophilic compound extracted from root of Salvia miltiorrhiza (Danshen), has demonstrated multiple pharmacological activities, including anti-inflammation, anti-proliferation and anti-infection. However, the effect of CTS on pulmonary fibrosis is unknown. This study aims to investigate the effects of CTS treatment on pulmonary fibrosis and its underlying mechanism. The pulmonary fibrosis model was established by intratracheal instillation of bleomycin (5 mg/kg) in Sprague-Dawley rats (in vivo) and stimulating human fetal lung fibroblasts (HLFs) with transforming growth factor-beta 1 (TGF-β1) (in vitro). CTS (7.5, 15, 30, 60 mg/kg/day) and pirfenidone (150 mg/kg/day, positive control) were administered by oral gavage for 28 days. In this study, we found CTS treatment improved pulmonary function, relieved pathological changes and attenuated the accumulation of extracellular matrix in pulmonary fibrosis rat model induced by bleomycin. Mechanistically, CTS suppressed phosphorylation of Smad2/3 and STAT3 induced by TGF-β1 in HLFs. Stattic, a 1-benzothiophene based small-molecule STAT3 inhibitor, resulted in a significant down-regulation of fibrosis biomarkers including fibronectin, collagen type I and alpha smooth muscle actin (α-SMA). Overexpression of STAT3 promoted expression of fibrosis biomarkers in HLFs cell model induced by TGF-β1 and partially blocked the inhibitory effect of CTS on TGF-β1-induced fibrosis response. Taken together, these results suggested that CTS protects against pulmonary fibrosis via inhibition of Smad and STAT3 signaling pathways. Thus, CTS may represent a promising drug candidate for treating pulmonary fibrosis.

Salvianolic Acids: Potential Source of Natural Drugs for the Treatment of Fibrosis Disease and Cancer

Salvianolic acids, the most effective and abundant compounds extracted from Salvia miltiorrhiza (Danshen), are well known for its good anti-oxidative activity. Danshen has been extensively used as a traditional medicine to treat cardiovascular-related diseases in China and other Asian countries for hundreds of years. Recently, more and more studies have demonstrated that salvianolic acids also have a good effect on the alleviation of fibrosis disease and the treatment of cancer. In vivo and in vitro experiments have demonstrated that salvianolic acids can modulate signal transduction within fibroblasts and cancer cells. It is discovered that the cancer treatment of salvianolic acids is not only because salvianolic acids promote the apoptosis of cancer cells, but also due to the inhibition of cancer-associated epithelial-mesenchymal transition processes. In this article, we review a variety of studies focusing on the comprehensive roles of salvianolic acids in the treatment of fibrosis disease and cancer. These perspectives on the therapeutic potential of salvianolic acids highlight the importance of these compounds, which could be the novel and attractive drugs for fibrosis disease and cancer.

Polydatin ameliorates pulmonary fibrosis by suppressing inflammation and the epithelial mesenchymal transition via inhibiting the TGF-β/Smad signaling pathway

Pulmonary fibrosis is a chronic and progressive lung disease which results in a loss of pulmonary function and eventually respiratory failure. Inflammation and epithelial mesenchymal transition (EMT) play important roles in the pathogenesis of pulmonary fibrosis. This study aimed to investigate the therapeutic effect of polydatin (PD) in bleomycin-induced pulmonary fibrosis. A bleomycin-induced pulmonary fibrosis animal model used SD rats. Morphological changes were analyzed by hematoxylin-eosin staining. RT-qPCR and western blot were used for the detection of the expression of TGF-β1, collagen I, collagen III, E-cadherin, fibronectin and the ratios of p-Smad2/Smad2, p-Smad3/Smad3. The concentrations of PICP, PIIINP, TNF-α, IL-1β, IL-6 and IL-17 were measured by enzyme linked immunosorbent assay (Elisa) assay. Results showed that PD attenuated bleomycin-induced pulmonary fibrosis. The beneficial effect of PD was possibly related to the inhibition of inflammation and EMT through suppressing the TGF-β/Smad signaling pathway. Our findings suggested that PD might be a potential therapeutic candidate in the treatment of pulmonary fibrosis.

Pulmonary fibrosis is a chronic and progressive lung disease which results in a loss of pulmonary function and eventually respiratory failure.

Salvianolic acid B attenuates experimental skin fibrosis of systemic sclerosis

Systemic sclerosis (SSc) is a connective tissue disease characterized mainly by fibrosis of skin and internal organs. Our previous study has shown that salvianolic acid B (SAB), a bioactive component extracted from Salvia miltiorrhiza (SM), was one of the essential ingredients in the traditional Chinese medicine Yiqihuoxue formula, which has been used to treat SSc-related dermal and pulmonary fibrosis. The aim of the present study was to evaluate the effect of SAB on skin fibrosis and explore its underlying anti-fibrotic mechanism. We found that SAB was capable of alleviating skin fibrosis in a bleomycin-induced SSc mouse model, alleviating skin thickness and reducing collagen deposition. in vitro studies indicated that SAB reduced SSc skin fibroblast proliferation and downregulated extracellular matrix gene transcription and collagen protein expression. TGF-β/SMAD and MAPK/ERK pathway activation were also shown to be suppressed in SAB treated fibroblasts. Moreover, RNA-seq revealed that the anti-fibrotic effect of SAB might be related to antioxidant activity, the cell cycle, and the p53 signaling pathway. Taken together, our results suggest that SAB has the ability to alleviate SSc-related skin fibrosis both in vivo and in vitro.

Salvianolate reduces atrial fibrillation through suppressing atrial interstitial fibrosis by inhibiting TGF-β1/Smad2/3 and TXNIP/NLRP3 inflammasome signaling pathways in post-MI rats

BACKGROUND

Salvianolate is the main water-soluble bioactive compound of Salvia Miltiorrhiza Bunge and is now clinically used in the treatment of cardiovascular diseases in China. However, its applications in the prevention of atrial interstitial fibrosis (AIF) and atrial fibrillation (AF) are not fully revealed.

PURPOSES

To investigate the preventive effect of salvianolate on the pathogenesis of AF in post-myocardial infarction (MI) rats and to elucidate the potential mechanisms.

MATERIALS AND METHODS

Rats underwent left anterior descending coronary artery ligation were randomized into four groups and administered intraperitoneally with vehicle (MI group, n = 13), or 10, 20 and 40 mg/kg salvianolate (Sal-L, Sal-M and Sal-H group, n = 13, 14 and 13 respectively) for totally five weeks. Rats underwent sham operation was used as control group (Sham, n = 10). Then, echocardiography and AF inducibility test were detected. Tissues and serum were collected for Sirius red and fast green counter stain or hematoxylin-eosin to assess atrial interstitial fibrosis and hypertrophy, or for western blot and ELISA analysis.

RESULTS

Salvianolate injection significantly improved cardiac function, reduced left atrial enlargement and P-wave duration, and decreased not only the vulnerability to AF but also AF duration. Histologic analysis showed that salvianolate mitigated AIF and atrial hypertrophy. Western blot analysis found that salvianolate inhibited the TGFβ1/Smad2/3 mediated-collagen deposition and inhibited the TXNIP/NLRP3 inflammasome /IL-1β and IL-18 signal pathway. ELISA analysis showed that salvianolate significantly reduced the serum concentrations of BNP, IL-6, CRP and TGFβ1.

CONCLUSIONS

Salvianolate may constitute a novel upstream therapy for AF by suppressing AIF. The underlying mechanism may be attributable to its inhibitory effects on TGF-β1/Smad2/3 and TXNIP/NLRP3 inflammasome signaling pathway.

Salvianolic Acid B-Alleviated Angiotensin II Induces Cardiac Fibrosis by Suppressing NF-κB Pathway In Vitro

BACKGROUND Salvianolic acid B (SalB) is the representative component of phenolic acids derived from the roots and rhizomes of Salvia miltiorrhiza Bge (Labiatae), which has been used widely in Asian countries for clinical therapy of various cardiovascular dysfunction-related diseases. However, cardiac protection effects and the underlying mechanism for clinical application are still poorly understood. Here, we investigated the potential anti-myocardial fibrosis effect and mechanism of SalB on Angiotensin II (Ang II)-induced cardiac fibrosis in vitro. MATERIAL AND METHODS The proliferation and migration capacity of cardiac fibroblasts (CFBs) were measured by MTT assay and scratch analysis, respectively. The colorimetric assay determined the hydroxyproline content in medium. Western blotting detected the protein expressions of nuclear transcription factor-kappa B (NF-κB) pathway-associated proteins, fibronectin (FN), collagen type I (Coll I), α-smooth muscle actin (α-SMA), and connective tissue growth factor (CTGF). The expression of α-SMA protein was observed by immunofluorescence staining. qRT-PCR detected the mRNA expression of NF-κB. RESULTS SalB attenuated Ang II-induced the proliferation and the migration ability of CFBs. Ang II-induced the extracellular matrix protein Coll I, FN, and α-SMA, the pro-fibrotic cytokine CTGF protein expression was inhibited, and the nuclear translocation of NF-κB p65 subunit was reduced by SalB. Western blotting and qRT-PCR confirmed that SalB blocked the activation of NF-κB induced by Ang II. PDTC (the NF-κB inhibitor) also inhibited proliferation of CFBs and reduced α-SMA and Coll I expression induced by Ang II. CONCLUSIONS SalB can alleviate Ang II-induced cardiac fibrosis via suppressing the NF-κB pathway in vitro.

Salvianolic acid B as an anti-emphysema agent I: In vitro stimulation of lung cell proliferation and migration, and protection against lung cell death, and in vivo lung STAT3 activation and VEGF elevation

Emphysema causes progressive and life-threatening alveolar structural destruction/loss, yet remains irreversible and incurable to date. Impaired vascular endothelial growth factor (VEGF) signaling has been proposed as a new pathogenic mechanism, and if so, VEGF recovery may enable reversal of emphysema. Thus, we hypothesized that salvianolic acid B (Sal-B), a polyphenol in traditional Chinese herbal danshen, is an alveolar structural recovery agent for emphysema by virtue of VEGF stimulation/elevation via activation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), as stimulating lung cell proliferation and migration, and protecting against lung cell death. Using in vitro human lung microvascular endothelial (HMVEC-L) and alveolar epithelial (A549) cell systems, Sal-B was examined for 1) stimulation of cell proliferation by the MTT and BrdU assays; 2) promotion of cell migration by the scratch wound closure assay; 3) protection against emphysema-like induced cell death by the trypan blue exclusion and flow cytometry assays; and 4) mechanistic involvement of JAK2/STAT3/VEGF in these activities. Sal-B was also spray-dosed to the lungs of healthy rats for two weeks to verify the lung's STAT3 activation and VEGF elevation by western blot, as well as the absence of functional and morphological abnormalities. All the in vitro cell-based activities were concentration-dependent. At 25 μM, Sal-B 1) stimulated cell proliferation by 1.4-2.6-fold; 2) promoted migratory cell wound closure by 1.5-1.7-fold; and 3) protected against cell death induced with H₂O₂ (oxidative stress) and SU5416 (VEGF receptor blockade) by 49-86%. JAK2 and STAT3 inhibitors and VEGF receptor antagonist each opposed these Sal-B's activities by over 65%, suggesting the mechanistic involvement of JAK2/STAT3 activation and VEGF stimulation/elevation. In rats, Sal-B at 0.2 mg/kg enabled 1.9 and 1.5-fold increased STAT3 phosphorylation and VEGF elevation in the lungs, respectively, while causing no functional and morphological abnormalities. Hence, Sal-B was projected to be a new class of anti-emphysema agent capable of reversing alveolar structural destruction/loss via JAK2/STAT3/VEGF-dependent stimulation of lung cell proliferation and migration, and inhibition of induced lung cell death.

Salvianolic acid B attenuates experimental pulmonary inflammation by protecting endothelial cells against oxidative stress injury

Endothelial cell injury and subsequent inflammation play pivotal roles in the pathogenesis of pulmonary fibrosis, a progressive and fatal disorder. We found previously that salvianolic acid B (SAB) attenuated experimental pulmonary fibrosis. Pulmonary fibrosis is driven by inflammation, but the anti-inflammatory role and mechanism of SAB on the treatment of pulmonary fibrosis is still unknown. Here, our in vivo studies showed that SAB had a strong anti-inflammatory effect on bleomycin-instilled mice by inhibiting inflammatory cell infiltration and inflammatory cytokine production. Moreover, SAB protected endothelial cells against oxidative stress injury and inhibited endothelial cell apoptosis in bleomycin-treated mice. The in vitro studies also showed that SAB decreased the H₂O₂-induced overproduction of reactive oxygen species to protect EA.hy926 endothelial cells from oxidative damage, and further inhibited H₂O₂-induced permeability and overexpression of pro-inflammatory molecules. The next studies revealed that SAB inhibited the H₂O₂-induced cell apoptosis and attenuated the decrease of tight junction-related gene expression, resulting in a decrease of the endothelial permeability in injured endothelial cells. Furthermore, Western blot analysis suggested that SAB decreased endothelial cell permeability and expression of pro-inflammatory cytokines by inhibiting MAPK and NF-κB signaling pathways. Taken together, these data indicate that SAB exerted anti-inflammatory roles in pulmonary fibrosis by protection of the endothelial cells against oxidative stress injury, mediated by inhibition of endothelial permeability and expression of pro-inflammatory cytokine via the MAPK and NF-κB signaling pathways.

MiR-3606-3p inhibits systemic sclerosis through targeting TGF-β type II receptor

Systemic sclerosis (SSc) is a multisystemic fibrotic disease characterized by excessive collagen deposition and extracellular matrix synthesis. Though transforming growth factor-β (TGF-β) plays a fundamental role in the pathogenesis of SSc, the mechanism by which TGF-β signaling acts in SSc remains largely unclear. Here, we showed that TGF-β type II receptor (TGFBR2) was significantly upregulated in both human SSc dermal tissues and primary fibroblasts. In fibroblasts, siRNA-induced knockdown of TGFBR2 resulted in a reduction of p-SMAD2/3 levels and reduced production of type I collagen. Additionally, functional experiments revealed that downregulation of TGFBR2 yielded an anti-growth effect on fibroblasts through inhibiting cell cycle progression. Further studies showed that miR-3606-3p could directly target the 3'-UTR of TGFBR2 and significantly decrease the levels of both TGFBR2 mRNA and protein. Furthermore, SSc dermal tissues and primary fibroblasts contain significantly reduced amounts of miR-3606-3p, and the overexpression of miR-3606-3p in fibroblasts replicates the phenotype of TGFBR2 downregulation. Collectively, our findings demonstrated that increased TGFBR2 could be responsible for the hyperactive TGF-β signaling observed in SSc. Moreover, we identified a pivotal role for miR-3606-3p in SSc, which acts, at least partly, through the attenuation of TGF-β signaling via TGFBR2 repression, suggesting that the regulation of miR-3606-3p/TGFBR2 could be a promising therapeutic target that could improve the treatment strategy for fibrosis.