The Role of Butylidenephthalide in Targeting the Microenvironment Which Contributes to Liver Fibrosis Amelioration

Therapeutic potential and mechanism of Chinese herbal medicines in treating fibrotic liver disease

Liver fibrosis is a pathological condition characterized by replacement of normal liver tissue with scar tissue, and also the leading cause of liver-related death worldwide. During the treatment of liver fibrosis, in addition to antiviral therapy or removal of inducers, there remains a lack of specific and effective treatment strategies. For thousands of years, Chinese herbal medicines (CHMs) have been widely used to treat liver fibrosis in clinical setting. CHMs are effective for liver fibrosis, though its mechanisms of action are unclear. In recent years, many studies have attempted to determine the possible mechanisms of action of CHMs in treating liver fibrosis. There have been substantial improvements in the experimental investigation of CHMs which have greatly promoted the understanding of anti-liver fibrosis mechanisms. In this review, the role of CHMs in the treatment of liver fibrosis is described, based on studies over the past decade, which has addressed the various mechanisms and signaling pathways that mediate therapeutic efficacy. Among them, inhibition of stellate cell activation is identified as the most common mechanism. This article provides insights into the research direction of CHMs, in order to expand its clinical application range and improve its effectiveness.

Knockdown of Yap attenuates TAA-induced hepatic fibrosis by interaction with hedgehog signals

Liver fibrosis is an aberrant wound healing response to tissue injury characterized by excessive extracellular matrix deposition and loss of normal liver architecture. Hepatic stellate cells (HSCs) activation is regards to be the major process in liver fibrogenesis which is dynamic and reversible. Both Hippo signaling core factor Yap and Hedgehog (Hh) signaling promote HSCs transdifferentiation thereby regulating the repair process of liver injury. However, the molecular function of YAP and the regulation between Yap and Hh during fibrogenesis remain uncertain. In this study, the essential roles of Yap in liver fibrosis were investigated. Yap was detected to be increased in liver fibrotic tissue by the thioacetamide (TAA)-induced zebrafish embryonic and adult models. Inhibition of Yap by both embryonic morpholino interference and adult's inhibitor treatment was proved to alleviate TAA-induced liver lesions by and histology and gene expression examination. Transcriptomic analysis and gene expression detection showed that Yap and Hh signaling pathway have a cross talking upon TAA-induced liver fibrosis. In addition, TAA induction promoted the nuclear colocalization of YAP and Hh signaling factor GLI2α. This study demonstrates that Yap and Hh play synergistic protective roles in liver fibrotic response and provides new theoretical insight concerning the mechanisms of fibrosis progression.

A DUSP6 inhibitor suppresses inflammatory cardiac remodeling and improves heart function after myocardial infarction

Acute myocardial infarction (MI) results in loss of cardiomyocytes and abnormal cardiac remodeling with severe inflammation and fibrosis. However, how cardiac repair can be achieved by timely resolution of inflammation and cardiac fibrosis remains incompletely understood. Our previous findings have shown that dual-specificity phosphatase 6 (DUSP6) is a regeneration repressor from zebrafish to rats. In this study, we found that intravenous administration of the DUSP6 inhibitor (E)-2-benzylidene-3-(cyclohexylamino)-2,3-dihydro-1H-inden-1-one (BCI) improved heart function and reduced cardiac fibrosis in MI rats. Mechanistic analysis revealed that BCI attenuated macrophage inflammation through NF-κB and p38 signaling, independent of DUSP6 inhibition, leading to the downregulation of various cytokines and chemokines. In addition, BCI suppressed differentiation-related signaling pathways and decreased bone-marrow cell differentiation into macrophages through inhibiting DUSP6. Furthermore, intramyocardial injection of poly (D, L-lactic-co-glycolic acid)-loaded BCI after MI had a notable effect on cardiac repair. In summary, BCI improves heart function and reduces abnormal cardiac remodeling by inhibiting macrophage formation and inflammation post-MI, thus providing a promising pro-drug candidate for the treatment of MI and related heart diseases. This article has an associated First Person interview with the first author of the paper.

HOXA13 promotes liver regeneration through regulation of BMP-7

In-depth knowledge of liver regeneration could facilitate the development of therapies for liver injury and liver failure. As a member of the homeobox superfamily, HOXA13 plays an important role in regulating tumorigenesis and development. However, the exact role of HOXA13 in liver regeneration remains unclear. In this study, we confirmed that HOXA13 promotes hepatocyte proliferation both in vivo and in vitro. HOXA13 was upregulated during liver regeneration, and its overexpression further accelerated hepatocyte proliferation and liver function recovery during liver regeneration. Furthermore, we found that HOXA13 promoted hepatocyte proliferation and liver regeneration by upregulating bone morphogenetic protein-7 (BMP-7) mRNA. These findings provide a new potential target for the treatment of liver failure.

The Potential Application of Chinese Medicine in Liver Diseases: A New Opportunity

Liver diseases have been a common challenge for people all over the world, which threatens the quality of life and safety of hundreds of millions of patients. China is a major country with liver diseases. Metabolic associated fatty liver disease, hepatitis B virus and alcoholic liver disease are the three most common liver diseases in our country, and the number of patients with liver cancer is increasing. Therefore, finding effective drugs to treat liver disease has become an urgent task. Chinese medicine (CM) has the advantages of low cost, high safety, and various biological activities, which is an important factor for the prevention and treatment of liver diseases. This review systematically summarizes the potential of CM in the treatment of liver diseases, showing that CM can alleviate liver diseases by regulating lipid metabolism, bile acid metabolism, immune function, and gut microbiota, as well as exerting anti-liver injury, anti-oxidation, and anti-hepatitis virus effects. Among them, Keap1/Nrf2, TGF-β/SMADS, p38 MAPK, NF-κB/IκBα, NF-κB-NLRP3, PI3K/Akt, TLR4-MyD88-NF-κB and IL-6/STAT3 signaling pathways are mainly involved. In conclusion, CM is very likely to be a potential candidate for liver disease treatment based on modern phytochemistry, pharmacology, and genomeproteomics, which needs more clinical trials to further clarify its importance in the treatment of liver diseases.

N-butylidenephthalide ameliorates high-fat diet-induced obesity in mice and promotes browning through adrenergic response/AMPK activation in mouse beige adipocytes

Thermogenesis (non-exercise activity) in brown adipose tissue (BAT) promotes energy expenditure because of its higher number of mitochondria than white adipose tissue (WAT). The main function of thermogenesis in BAT can counteract obesity through the dissipation of calories as heat. N-butylidenephthalide (BP) is a natural derivative from Angelica sinensis, a Chinese herb that has been used for thousands of years. In this report, we demonstrated that BP improved the metabolic profiles of mice with high fat diet-induced obesity (DIO) by preventing weight gain, improving serum blood parameters, enhancing energy expenditure, stimulating white fat browning, and reversing hepatic steatosis. Further investigations demonstrated that BP administration upregulated the mRNA expression of beige (CD137, TMEM26) and brown fat selected genes (UCP1, PRDM16, PGC-1α, PPARγ) in white adipose tissues. In vitro studies, BP treatment increased multilocular lipid droplet levels, induced β-adrenergic receptor (cAMP/PKA) and AMP-activated protein kinase (AMPK) signaling (AMPK/acetyl-CoA carboxylase/SIRT1), and increased oxygen consumption in murine differentiated beige adipocytes, and the effects of BP were blocked by an AMPK inhibitor. BP promoted the interaction of AMPK with PGC-1α in beige adipocytes. Our findings provide novel insights into the application of BP in regulating energy metabolism and suggest its utility for clinical use in the treatment of obesity and related diseases.

Enhancement of cytotoxicity and induction of apoptosis by cationic nano-liposome formulation of n-butylidenephthalide in breast cancer cells

Breast cancer is the second most common malignancy in women. Current clinical therapy for breast cancer has many disadvantages, including metastasis, recurrence, and poor quality of life. Furthermore, it is necessary to find a new therapeutic drug for breast cancer patients to meet clinical demand. n-Butylidenephthalide (BP) is a natural and hydrophobic compound that can inhibit several tumors. However, BP is unstable in aqueous or protein-rich environments, which reduces the activity of BP. Therefore, we used an LPPC (Lipo-PEG-PEI complex) that can encapsulate both hydrophobic and hydrophilic compounds to improve the limitation of BP. The purpose of this study is to investigate the anti-tumor mechanisms of BP and BP/LPPC and further test the efficacy of BP encapsulated by LPPC on SK-BR-3 cells. BP inhibited breast cancer cell growth, and LPPC encapsulation (BP/LPPC complex) enhanced the cytotoxicity on breast cancer by stabilizing the BP activity and offering endocytic pathways. Additionally, BP and LPPC-encapsulated BP induced cell cycle arrest at the G₀/G₁ phase and might trigger both extrinsic as well as intrinsic cell apoptosis pathway, resulting in cell death. Moreover, the BP/LPPC complex had a synergistic effect with doxorubicin of enhancing the inhibitory effect on breast cancer cells. Consequently, LPPC-encapsulated BP could improve the anti-cancer effects on breast cancer in vitro. In conclusion, BP exhibited an anti-cancer effect on breast cancer cells, and LPPC encapsulation efficiently improved the cytotoxicity of BP via an acceleration of entrapment efficiency to induce cell cycle block and apoptosis. Furthermore, BP/LPPC exhibited a synergistic effect in combination with doxorubicin.

Interleukin-22 regulating Kupffer cell polarization through STAT3/Erk/Akt crosstalk pathways to extenuate liver fibrosis

AIMS

Interleukin (IL)-22 activates multiple signaling pathways to exert anti-inflammatory effects, but few studies have examined whether and how IL-22 may shift macrophage polarization between M1 (pro-inflammatory) and M2 (anti-inflammatory) states and thereby influence the progression of hepatic fibrosis.

MAIN METHODS

Utilized CCl4 to induce liver fibrosis in mice, detected the role of IL-22 in inhibiting liver fibrosis by regulating Kupffer cells (KCs) polarization in vivo and in vitro. U937 cells were used to confirm the mechanism of IL-22 regulating macrophage polarization via the STAT3/Erk/Akt pathways. Human liver specimens were collected to verify the correlation between the levels of IL-22 and KCs during liver fibrogenesis.

KEY FINDINGS

During CCl4-induced liver fibrosis progression in mice, adding exogenous IL-22 significantly inhibited pro-fibrogenic and macrophage phenotype-altering factors secreted by M1-KCs, and it increased the number of M2-KCs. In co-cultures of hepatic stellate cells and KCs from mice treated with IL-22, a high M2/M1-KCs ratio inhibited collagen production and stellate cell activation. These results suggest that IL-22 can increase the ratio of M2-KCs to M1-KCs and thereby attenuate the progression of liver fibrosis. Mechanistic studies in vitro showed that IL-22 promoted polarization of lipopolysaccharide-treated U937 macrophages from M1 to M2. The cytokine exerted these effects by activating the STAT3 pathway while suppressing Erk1/2 and Akt pathways. Furthermore, immunofluorescent staining in human liver specimens confirmed that IL-22 levels positively correlated with the number of M2-KCs during liver fibrogenesis.

SIGNIFICANCE

IL-22 regulates the STAT3/Erk/Akt to increase the M2/M1-KCs ratio and thereby slow liver fibrogenesis.

The Versatile Role of Matrix Metalloproteinase for the Diverse Results of Fibrosis Treatment

Fibrosis is a type of chronic organ failure, resulting in the excessive secretion of extracellular matrix (ECM). ECM protects wound tissue from infection and additional injury, and is gradually degraded during wound healing. For some unknown reasons, myofibroblasts (the cells that secrete ECM) do not undergo apoptosis; this is associated with the continuous secretion of ECM and reduced ECM degradation even during de novo tissue formation. Thus, matrix metalloproteinases (MMPs) are considered to be a potential target of fibrosis treatment because they are the main groups of ECM-degrading enzymes. However, MMPs participate not only in ECM degradation but also in the development of various biological processes that show the potential to treat diseases such as stroke, cardiovascular diseases, and arthritis. Therefore, treatment involving the targeting of MMPs might impede typical functions. Here, we evaluated the links between these MMP functions and possible detrimental effects of fibrosis treatment, and also considered possible approaches for further applications.

Targeting the PI3K/STAT3 axis modulates age-related differences in macrophage phenotype in rats with myocardial infarction

Ageing is associated with impaired repair mechanisms in cardiovascular diseases. Macrophages contribute to cardiac fibrosis after myocardial infarction (MI). The phosphatidyl-inositol-3-kinase (PI3K) pathway has been shown to play a role in cardiac remodelling after MI. It remained unclear whether n-butylidenephthalide, a major component of Angelica sinensis, can attenuate cardiac fibrosis by regulating the PI3K/signal transducer and activator of transcription 3 (STAT3)-mediated macrophage phenotypes in ageing rats after MI. Twenty-four hours after ligation of the left anterior descending artery, young (2-month-old) and ageing (18-month-old) male Wistar rats were treated with either vehicle or n-butylidenephthalide for 4 weeks. There were similar infarct sizes in both age groups. Compared with young rats, ageing rats exhibited significant increased cardiac fibrosis after MI, which can be attenuated after administering n-butylidenephthalide. MI was associated with decreased activities of PI3K and STAT3 in ageing rats compared with young rats. In both age groups, n-butylidenephthalide effectively provided a significant increase of STAT3 phosphorylation, STAT3 activity, STAT3 nuclear translocation, myocardial IL-10 levels and the percentage of M2c macrophage and a decrease of myofibroblast infiltration. The effects of n-butylidenephthalide on increased IL-10 levels were reversed by LY294002 or S3I-201. Furthermore, LY294002 abolished the STAT3 phosphorylation, whereas PI3K activity was not affected following the inhibition of STAT3. In conclusions, the host environment is responsible for ageing-related myofibroblast dysregulation in response to MI which can be improved by administering n-butylidenephthalide via macrophage differentiation towards M2 phenotype by targeting the PI3K/STAT3 axis.

Oral Submucous Fibrosis: A Review on Etiopathogenesis, Diagnosis, and Therapy

Oral submucous fibrosis (OSF) is characterized by abnormal collagen deposition. It is a precancerous disorder and transforms into a malignant tumor in 1.5–15% of all cases. Symptoms include submucous fibrosis, ulceration, xerostomia, a burning sensation, and restricted mouth opening. All of these greatly interfere with patient quality of life. The present review introduces OSF from a molecular perspective and summarizes what is known about its underlying mechanisms, diagnostic biomarkers, and therapeutic interventions. In addition to the aggressive treatment of OSF, its prevention is also important. Future research should, therefore, focus on improving the oral health literacy of the patients susceptible to OSF.

Antitumor Effect of n-Butylidenephthalide Encapsulated on B16/F10 Melanoma Cells In Vitro with a Polycationic Liposome Containing PEI and Polyethylene Glycol Complex

Advanced melanoma can metastasize to distal organs from the skin and yield an aggressive disease and poor prognosis even after treatment with chemotherapeutic agents. The compound n-Butylidenephthalide (BP) is isolated from Angelica sinensis, which is used to treat anemia and gynecological dysfunction in traditional Chinese medicine. Studies have indicated that BP can inhibit cancers, including brain, lung, prostate, liver, and colon cancers. However, because BP is a natural hydrophobic compound, it is quickly metabolized by the liver within 24 h, and thus has limited potential for development in cancer therapy. This study investigated the anticancer mechanisms of BP through encapsulation with a novel polycationic liposome containing polyethylenimine (PEI) and polyethylene glycol complex (LPPC) in melanoma cells. The results demonstrated that BP/LPPC had higher cytotoxicity than BP alone and induced cell cycle arrest at the G₀/G₁ phase in B16/F10 melanoma cells. The BP/LPPC-treated cell indicated an increase in subG₁ percentage and TUNEL positive apoptotic morphology through induction of extrinsic and intrinsic apoptosis pathways. The combination of BP and LPPC and clinical drug 5-Fluorouracil had a greater synergistic inhibition effect than did a single drug. Moreover, LPPC encapsulation improved the uptake of BP values through enhancement of cell endocytosis and maintained BP cytotoxicity activity within 24 h. In conclusion, BP/LPPC can inhibit growth of melanoma cells and induce cell arrest and apoptosis, indicating that BP/LPPC has great potential for development of melanoma therapy agents.

Non-Canonical Regulation of Type I Collagen through Promoter Binding of SOX2 and Its Contribution to Ameliorating Pulmonary Fibrosis by Butylidenephthalide

Pulmonary fibrosis is a fatal respiratory disease that gradually leads to dyspnea, mainly accompanied by excessive collagen production in the fibroblast and myofibroblast through mechanisms such as abnormal alveolar epithelial cells remodeling and stimulation of the extracellular matrix (ECM). Our results show that a small molecule, butylidenephthalide (BP), reduces type I collagen (COL1) expression in Transforming Growth Factor beta (TGF-β)-induced lung fibroblast without altering downstream pathways of TGF-β, such as Smad phosphorylation. Treatment of BP also reduces the expression of transcription factor Sex Determining Region Y-box 2 (SOX2), and the ectopic expression of SOX2 overcomes the inhibitory actions of BP on COL1 expression. We also found that serial deletion of the SOX2 binding site on 3′COL1 promoter results in a marked reduction in luciferase activity. Moreover, chromatin immunoprecipitation, which was found on the SOX2 binding site of the COL1 promoter, decreases in BP-treated cells. In an in vivo study using a bleomycin-induced pulmonary fibrosis C57BL/6 mice model, mice treated with BP displayed reduced lung fibrosis and collagen deposition, recovering in their pulmonary ventilation function. The reduction of SOX2 expression in BP-treated lung tissues is consistent with our findings in the fibroblast. This is the first report that reveals a non-canonical regulation of COL1 promoter via SOX2 binding, and contributes to the amelioration of pulmonary fibrosis by BP treatment.

Mesenchymal Stem Cell Therapy of Pulmonary Fibrosis: Improvement with Target Combination

Although the clinical application of new drugs has been shown to be effective in slowing disease progression and improving the quality of life in patients with pulmonary fibrosis, the damaged lung tissue does not recover with these drugs. Thus, there is an urgent need to establish regenerative therapy, such as stem cell therapy or tissue engineering. Moreover, the clinical application of mesenchymal stem cell (MSC) therapy has been shown to be safe in humans with idiopathic pulmonary fibrosis (IPF). It seems that a combination of MSC transplantation and pharmaceutical therapy might have additional benefits; however, the experimental design for its efficacy is still lacking. In this review, we provide an overview of the mechanisms that were identified when IPF was treated with MSC transplantation or new drugs. To maximize the therapeutic effect, we suggest that MSC transplantation is combined with drug application for synergistic effects. This review provides clinicians and scientists with the most efficient medical options, in the hope that this will spur on future research and lead to an eventual cure for this disease.

Butylidenephthalide abrogates the myofibroblasts activation and mesenchymal transdifferentiation in oral submucous fibrosis

Oral submucous fibrosis (OSF) is a premalignant disorder in the oral cavity, and areca nut chewing habit has been implicated in the persistent activation of myofibroblasts and the subsequent fibrosis. Therefore, it is critical to ameliorate the excessive activities of myofibroblasts prior to the malignant transformation of OSF. In the current study, we evaluated the cytotoxicity of butylidenephthalide (BP), a major phthalide ingredient of Angelica sinensis, in fibrotic buccal mucosal fibroblasts (fBMFs) as well as various myofibroblast hallmarks, including the phenotypical characteristics and fibrosis-related markers. Our results demonstrated that myofibroblast activities, including collagen gel contraction, migration, invasion and wound healing abilities were inhibited in response to BP. The expression levels of myofibroblast marker, α-smooth muscle actin (α-SMA), fibronectin and type 1 collagen A1 were decreased after exposure of BP. Moreover, we found that the EMT-related markers, Twist, Snail and ZEB1 were all downregulated after BP treatment. Most importantly, our findings demonstrated that BP impeded the binding of Snail to the E-box region in the α-SMA promoter, which may lead to inhibition of the arecoline-induced myofibroblast activities. Collectively, our data indicated that BP reduced numerous myofibroblast features in fBMFs and hindered the binding of Snail to α-SMA, thereby may function as an effective and natural antifibrosis compound.

Liver regeneration during the associating liver partition and portal vein ligation for staged hepatectomy procedure in Sus scrofa is positively modulated by stem cells

This present study investigated the impact of the application of stem cells to liver regeneration following the first stage of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). The experiment was conducted on a pig model (n=6, 3 that did not receive application of stem cells, 3 that received application stem cells). Collected samples of liver (day 0 and 9 following surgery) were subjected to complete transcriptome sequencing. In total, 39 differentially expressed genes were found in the group without the application of the stem cells (genes of unwanted processes such as fibrosis and inflammation). In the group that did receive application of stem cells, no significantly differentially expressed genes were found, indicating a properly regenerated liver remnant. The present study therefore demonstrated, to the best of our knowledge for the first time, the positive effect of stem cells application in the liver regeneration process during ALPPS procedure in the pig model.

BMP Signalling at the Crossroad of Liver Fibrosis and Regeneration

Bone Morphogenetic Proteins (BMPs) belong to the Transforming Growth Factor-β (TGF-β) family. Initially identified due to their ability to induce bone formation, they are now known to have multiple functions in a variety of tissues, being critical not only during development for tissue morphogenesis and organogenesis but also during adult tissue homeostasis. This review focus on the liver as a target tissue for BMPs actions, devoting most efforts to summarize our knowledge on their recently recognized and/or emerging roles on regulation of the liver regenerative response to various insults, either acute or chronic and their effects on development and progression of liver fibrosis in different pathological conditions. In an attempt to provide the basis for guiding research efforts in this field both the more solid and more controversial areas of research were highlighted.

n-Butylidenephthalide exhibits protection against neurotoxicity through regulation of tryptophan 2, 3 dioxygenase in spinocerebellar ataxia type 3

Spinocerebellar ataxia type 3 or Machado-Joseph disease (SCA3/MJD) is characterized by the repetition of a CAG codon in the ataxin-3 gene (ATXN3), which leads to the formation of an elongated mutant ATXN3 protein that can neither be denatured nor undergo proteolysis in the normal manner. This abnormal proteolysis leads to the accumulation of cleaved fragments, which have been identified as toxic and further they act as a seed for more aggregate formation, thereby increasing toxicity in neuronal cells. To date, there have been few studies or treatment strategies that have focused on controlling toxic fragment formation. The aim of this study is to develop a potential treatment strategy for addressing the complications of toxic fragment formation and to provide an alternative treatment strategy for SCA3. Our preliminary data on anti-aggregation and toxic fragment formation using an HEK (human embryonic kidney cells) 293T-84Q-eGFP (green fluorescent protein) cell model identified n-butylidenephthalide (n-BP) as a potential drug treatment for SCA3. n-BP decreased toxic fragment formation in both SCA3 cell and animal models. Moreover, results showed that n-BP can improve gait, motor coordination, and activity in SCA3 mice. To comprehend the molecular basis behind the control of toxic fragment formation, we used microarray analysis to identify tryptophan metabolism as a major player in controlling the fate of mutant ATXN3 aggregates. We also demonstrated that n-BP functions by regulating the early part of the kynurenine pathway through the downregulation of tryptophan 2, 3-dioxygenase (TDO2), which decreases the downstream neurotoxic product, quinolinic acid (QA). In addition, through the control of TDO2, n-BP also decreases active calpain levels, an important enzyme involved in the proteolysis of mutant ATXN3, thereby decreasing toxic fragment formation and associated neurotoxicity. Collectively, these findings indicate a correlation between n-BP, TDO2, QA, calpain, and toxic fragment formation. Thus, this study contributes to a better understanding of the molecular interactions involved in SCA3, and provides a novel potential treatment strategy for this neurodegenerative disease.