Pirfenidone effectively reverses experimental liver fibrosis

Ziziphus spina-christi L. extract attenuates bleomycin-induced lung fibrosis in mice via regulating TGF-β1/SMAD pathway: LC-MS/MS Metabolic profiling, chemical composition, and histology studies

Ancient Egyptians (including Bedouins and Nubians) have long utilized Ziziphus spina-christi (L.), a traditional Arabian medicinal herb, to alleviate swellings and inflammatory disorders. It is also mentioned in Christian and Muslim traditions. Ziziphus spina-christi L. (Family: Rhamnaceae) is a plentiful source of polyphenols, revealing free radical scavenging, antioxidant, metal chelating, cytotoxic, and anti-inflammatory activities. Herein, different classes of the existing bioactive metabolites in Z. spina-christi L. were detected using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the first time. The study also aimed to assess the anti-inflammatory and antifibrotic properties of Z. spina-christi L. extract against bleomycin-induced lung fibrosis in an experimental mouse model. 32 male Swiss Albino mice were assigned into 4 groups; the first and second were the normal control group and the bleomycin positive control (single 2.5 U/kg bleomycin intratracheal dose). The third and fourth groups received 100 and 200 mg/kg/day Z. spina-christi L. extract orally for 3 weeks, 2 weeks before bleomycin, and 1 week after. The bioactive metabolites in Z. spina-christi L. extract were identified as phenolic acids, catechins, flavonoids, chalcones, stilbenes, triterpenoid acids, saponins, and sterols. The contents of total phenolic compounds and flavonoids were found to be 196.62 mg GAE/gm and 33.29 mg QE/gm, respectively. In the experimental study, histopathological examination revealed that lung fibrosis was attenuated in both Z. spina-christi L.- treated groups. Z. spina-christi L. extract downregulated the expression of nuclear factor kappa B (NF-κB) p65 and decreased levels of the inflammatory markers tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and c-Jun N-terminal kinase (JNK) in lung tissue. Z. spina-christi L. also downregulated the expression of the fibrotic parameters collagen-1, alpha-smooth muscle actin (α-SMA), transforming growth factor-beta 1 (TGF-β1), matrix metalloproteinase-9 (MMP-9) and SMAD3, with upregulation of the antifibrotic SMAD7 in lung tissue. Overall, the present study suggests a potential protective effect of Z. spina-christi L. extract against bleomycin-induced lung fibrosis through regulation of the TGF-β1/SMAD pathway.

Novel therapeutics to treat chronic pancreatitis: targeting pancreatic stellate cells and macrophages

INTRODUCTION

Chronic pancreatitis (CP) is a persistent, recurrent, and progressive disorder that is characterized by chronic inflammation and irreversible fibrosis of the pancreas. It is associated with severe morbidity, resulting in intense abdominal pain, diabetes, exocrine and endocrine dysfunction, and an increased risk of pancreatic cancer. The etiological factors are diverse and the major risk factors include smoking, chronic alcoholism, as well as other environmental and genetic factors. The treatment and management of CP is challenging, and no definitive curative therapy is currently available.

AREAS COVERED

This review paper aims to provide an overview of the different cell types in the pancreas that is known to mediate disease progression and outline potential novel therapeutic approaches and drug targets that may be effective in treating and managing CP. The information presented in this review was obtained by conducting a NCBI PubMed database search, using relevant keywords.

EXPERT OPINION

In recent years, there has been an increased interest in the development of novel therapeutics for CP. A collaborative multi-disciplinary approach coupled with a consistent funding for research can expedite progress of translating the findings from bench to bedside.

On a deterministic mathematical model which efficiently predicts the protective effect of a plant extract mixture in cirrhotic rats

In this work, we propose a mathematical model that describes liver evolution and concentrations of alanine aminotransferase and aspartate aminotransferase in a group of rats damaged with carbon tetrachloride. Carbon tetrachloride was employed to induce cirrhosis. A second groups damaged with carbon tetrachloride was exposed simultaneously a plant extract as hepatoprotective agent. The model reproduces the data obtained in the experiment reported in [Rev. Cub. Plant. Med. 22(1), 2017], and predicts that using the plants extract helps to get a better natural recovery after the treatment. Computer simulations show that the extract reduces the damage velocity but does not avoid it entirely. The present paper is the first report in the literature in which a mathematical model reliably predicts the protective effect of a plant extract mixture in rats with cirrhosis disease. The results reported in this manuscript could be used in the future to help in fighting cirrhotic conditions in humans, though more experimental and mathematical work is required in that case.

Extracellular matrix remodelling in obesity and metabolic disorders

Obesity causes extracellular matrix (ECM) remodelling which can develop into serious pathology and fibrosis, having metabolic effects in insulin-sensitive tissues. The ECM components may be increased in response to overnutrition. This review will focus on specific obesity-associated molecular and pathophysiological mechanisms of ECM remodelling and the impact of specific interactions on tissue metabolism. In obesity, complex network of signalling molecules such as cytokines and growth factors have been implicated in fibrosis. Increased ECM deposition contributes to the pathogenesis of insulin resistance at least in part through activation of cell surface integrin receptors and CD44 signalling cascades. These cell surface receptors transmit signals to the cell adhesome which orchestrates an intracellular response that adapts to the extracellular environment. Matrix proteins, glycoproteins, and polysaccharides interact through ligand-specific cell surface receptors that interact with the cytosolic adhesion proteins to elicit specific actions. Cell adhesion proteins may have catalytic activity or serve as scaffolds. The vast number of cell surface receptors and the complexity of the cell adhesome have made study of their roles challenging in health and disease. Further complicating the role of ECM-cell receptor interactions is the variation between cell types. This review will focus on recent insights gained from studies of two highly conserved, ubiquitously axes and how they contribute to insulin resistance and metabolic dysfunction in obesity. These are the collagen-integrin receptor-IPP (ILK-PINCH-Parvin) axis and the hyaluronan-CD44 interaction. We speculate that targeting ECM components or their receptor-mediated cell signalling may provide novel insights into the treatment of obesity-associated cardiometabolic complications.

A Substituted-Rhodamine-Based Reversible Fluorescent Probe for In Vivo Quantification of Glutathione

Quantifying glutathione (GSH) in cells and organisms is of great significance for understanding the mechanism of oxidative stress in various physiological and pathological processes. However, the quantification by fluorescence bioimaging in living tissues has much stricter requirements than the "Petri dish"-cultured cells in flat plates. Based on the evaluation of the electronic structure and steric hindrance-tuned reactivity of phospha-substituted rhodamine with GSH, a reversible Förster resonance energy transfer (FRET) probe ZpSiP with a distinct performance (K_d =4.9 mM, t_1/2 =0.57 s, k=81 M^-1  s^-1 ) is developed for real time quantifying GSH in living cells. Furthermore, the near-infrared (NIR) probe succeeded in sensitively tracking the dynamics of GSH in the real organisms bearing tumors, chronic renal failure, and liver fibrosis for unveiling the related pathological processes. We believe that the advance in chemistry with quantitative analysis methods will initiate more promising progress and broad applications.

Effect and mechanism of pirfenidone combined with 2-methoxy-estradiol perfusion through portal vein on hepatic artery hypoxia-induced hepatic fibrosis

PURPOSE

The aim of this study was to explore the effect and mechanism of pirfenidone (PFD) combined with 2-methoxyestradiol (2-ME2) perfusion through portal vein on hepatic artery hypoxia-induced hepatic fibrosis.

MATERIALS AND METHODS

Sprague-Dawley rats were divided into 5 groups (n ​= ​3/group): control group, hepatic artery ligation (HAL) group, HAL ​+ ​PFD (portal vein perfusion of PFD) group, HAL+2-ME2 (portal vein perfusion of 2-ME2) group and HAL ​+ ​PFD+2-ME2 group depending on whether they received HAL and/or portal vein perfusion (PFD and/or 2-ME2). Livers were harvested for pathology, western blotting (WB), and quantitative real-time PCR (qRT-PCR).

RESULTS

Sirius red staining showed that portal vein perfusion of drugs resulted in degradation of liver fibrosis. Immunohistochemistry showed decreased hypoxia-inducible factor-1 α (HIF-1α) and α-smooth muscle actin (α-SMA) after portal intravenous drugs infusion compared with HAL group (P ​< ​0.05). WB analysis showed increased Smad7 in HAL ​+ ​PFD group compared with HAL group (P ​< ​0.05). qRT-PCR analysis showed decreased matrix metallo-proteinase 2 (MMP2), transforming growth factor β1 (TGF-β1), monocyte chemoattractant protein-1 (MCP-1), and Collagen I mRNA in HAL ​+ ​PFD group except for tissue inhibitor of metalloproteinase-1 (TIMP-1) compared with HAL group (P ​< ​0.05). Compared with HAL ​+ ​PFD group, the addition of 2-ME2 did not lead to better results in qRT-PCR analysis.

CONCLUSIONS

The portal vein perfusion of PFD significantly reduced the hepatic artery hypoxia-induced fibrosis degree in treated rats by down-regulating the expression of HIF-1α, α-SMA, MMP2, TGF-β1, MCP-1, and Collagen I, as well as up-regulating the TIMP-1 expression and Smad7 protein level. Combined 2-ME2 infusion was not better than PFD alone.

Fluorofenidone ameliorates cholestasis and fibrosis by inhibiting hepatic Erk/-Egr-1 signaling and Tgfβ1/Smad pathway in mice

Cholestasis is characterized by intrahepatic accumulation of bile acids (BAs), resulting in liver injury, fibrosis, and liver failure. To date, only ursodeoxycholic acid and obeticholic acid have been approved for the treatment of cholestasis. As fluorofenidone (AKF-PD) was previously reported to play significant anti-fibrotic and anti-inflammatory roles in various diseases, we investigated whether AKF-PD ameliorates cholestasis. A mouse model of cholestasis was constructed by administering a 0.1 % 3,5-diethoxycarbonyl-1,4-dihydroxychollidine (DDC) diet for 14 days. Male C57BL/6 J mice were treated with either AKF-PD or pirfenidone (PD) orally in addition to the DDC diet. Serum and liver tissues were subsequently collected and analyzed. We found that AKF-PD significantly reduced the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and total bile salts (TBA), as well as hepatic bile acids (BAs) levels. Hepatic histological analyses demonstrated that AKF-PD markedly attenuated hepatic inflammation and fibrosis. Further mechanistic analyses revealed that AKF-PD markedly inhibited expression of Cyp7a1, an enzyme key to BAs synthesis, by increasing Fxr nuclear translocation, and decreased hepatic inflammation by attenuating Erk/-Egr-1-mediated expression of inflammatory cytokines and chemokines Tnfα, Il-1β, Il-6, Ccl2, Ccl5 and Cxcl10. Moreover, AKF-PD was found to substantially reduce liver fibrosis via inhibition of Tgfβ1/Smad pathway in our mouse model. Here, we found that AKF-PD effectively attenuates cholestasis and hepatic fibrosis in the mouse model of DDC-induced cholestasis. As such, AKF-PD warrants further investigation as a candidate drug for treatment of cholestasis.

New Drugs for Hepatic Fibrosis

The morbidity and mortality of hepatic fibrosis caused by various etiologies are high worldwide, and the trend is increasing annually. At present, there is no effective method to cure hepatic fibrosis except liver transplantation, and its serious complications threaten the health of patients and cause serious medical burdens. Additionally, there is no specific drug for the treatment of hepatic fibrosis, and many drugs with anti-hepatic fibrosis effects are in the research and development stage. Recently, remarkable progress has been made in the research and development of anti-hepatic fibrosis drugs targeting different targets. We searched websites such as PubMed, ScienceDirect, and Home-ClinicalTrials.gov and found approximately 120 drugs with anti-fibrosis properties, some of which are in phase Ⅱ or Ⅲ clinical trials. Additionally, although these drugs are effective against hepatic fibrosis in animal models, most clinical trials have shown poor results, mainly because animal models do not capture the complexity of human hepatic fibrosis. Besides, the effect of natural products on hepatic fibrosis has not been widely recognized at home and abroad. Furthermore, drugs targeting a single anti-hepatic fibrosis target are prone to adverse reactions. Therefore, currently, the treatment of hepatic fibrosis requires a combination of drugs that target multiple targets. Ten new drugs with potential for development against hepatic fibrosis were selected and highlighted in this mini-review, which provides a reference for clinical drug use.

Pirfenidone ameliorates chronic pancreatitis in mouse models through immune and cytokine modulation

Chronic pancreatitis (CP) is an irreversible fibro-inflammatory disease of the pancreas with no current targeted therapy. Pirfenidone, an anti-fibrotic and anti-inflammatory drug, is FDA approved for treatment of Idiopathic Pulmonary Fibrosis (IPF). Its efficacy in ameliorating CP has never been evaluated before. We recently reported that pirfenidone improves acute pancreatitis in mouse models. The aim of the current study was to evaluate the therapeutic efficacy of pirfenidone in mouse models of CP. We used caerulein and L-arginine models of CP and administered pirfenidone with ongoing injury, or in well-established disease. We evaluated for fibrosis by Sirius-red staining for collagen, immunohistochemistry, western blotting, and qPCR for fibrosis markers to show the salutary effects of pirfenidone in CP. Our results suggest that treatment with pirfenidone ameliorated CP related changes in the pancreas (i.e., atrophy, acinar cell loss, fibrosis, and inflammation) not only when administered with ongoing injury, but also in well-established models of caerulein as well as L-arginine induced CP. It reduces the pro-fibrotic phenotype of macrophages (in-vivo and in-vitro), reduces macrophage infiltration into the pancreas and alters the intra-pancreatic cytokine milieu preceding changes in histology. The therapeutic effect of pirfenidone is abrogated in absence of macrophages. Furthermore, it reduces collagen secretion, cytokine levels and fibrosis markers in pancreatic stellate cells in-vitro. As it is FDA approved, our findings in mouse models simulating clinical presentation of patients to the clinic, can be used as the basis of a clinical trial evaluating the efficacy of this drug as a therapeutic agent for CP.

TGF-β1 mediates pathologic changes of secondary lymphedema by promoting fibrosis and inflammation

Background

Secondary lymphedema is a common complication of cancer treatment, and previous studies have shown that the expression of transforming growth factor‐beta 1 (TGF‐β1), a pro‐fibrotic and anti‐lymphangiogenic growth factor, is increased in this disease. Inhibition of TGF‐β1 decreases the severity of the disease in mouse models; however, the mechanisms that regulate this improvement remain unknown.

Methods

Expression of TGF‐β1 and extracellular matrix molecules (ECM) was assessed in biopsy specimens from patients with unilateral breast cancer‐related lymphedema (BCRL). The effects of TGF‐β1 inhibition using neutralizing antibodies or a topical formulation of pirfenidone (PFD) were analyzed in mouse models of lymphedema. We also assessed the direct effects of TGF‐β1 on lymphatic endothelial cells (LECs) using transgenic mice that expressed a dominant‐negative TGF‐β receptor selectively on LECs (LEC^DN‐RII).

Results

The expression of TGF‐β1 and ECM molecules is significantly increased in BCRL skin biopsies. Inhibition of TGF‐β1 in mouse models of lymphedema using neutralizing antibodies or with topical PFD decreased ECM deposition, increased the formation of collateral lymphatics, and inhibited infiltration of T cells. In vitro studies showed that TGF‐β1 in lymphedematous tissues increases fibroblast, lymphatic endothelial cell (LEC), and lymphatic smooth muscle cell stiffness. Knockdown of TGF‐β1 responsiveness in LEC^DN‐RII resulted in increased lymphangiogenesis and collateral lymphatic formation; however, ECM deposition and fibrosis persisted, and the severity of lymphedema was indistinguishable from controls.

Conclusions

Our results show that TGF‐β1 is an essential regulator of ECM deposition in secondary lymphedema and that inhibition of this response is a promising means of treating lymphedema.

A new approach based on CXCR4-targeted combination liposomes for the treatment of liver fibrosis

Liver fibrosis results from excessive extracellular matrix accumulation due to injury and leads to cirrhosis, cancer, and death. Herein, we propose a chemokine receptor 4 (CXCR4)-targeted combination (CTC) liposomal therapy to treat carbon tetrachloride (CCl₄)-induced liver fibrosis in a mouse model. This study aims to combine small molecules such as pirfenidone and AMD3100 in a single nanoplatform to investigate their synergistic antifibrotic effects in a setting of CCl₄-induced liver fibrosis. CTC liposomes (CTC lipo) were prepared using the thin-film hydration method. CTC lipo exhibited a spherical shape, and the particle size was recorded at the nanoscale which confirms its appropriateness for in vitro and in vivo applications. CTC lipo had good storage and serum stability. The entrapped drugs in CTC lipo showed reduced toxicity at higher concentrations. CTC lipo displayed CXCR4 mediated cell uptake and were internalized by caveolae-mediated endocytosis. CTC lipo showed CXCR4 targeting and stromal cell-derived factor 1α (SDF1-α)/CXCR4 axis blocking activity. CTC lipo reduced the elevated serum aspartate aminotransferase (AST), alanine transaminase (ALT), and hydroxyproline (HYP) levels. The histological studies showed improved liver architecture and reduced collagen deposition after treatment. Transforming growth factor β (TGFβ), alpha-smooth muscle actin (α-SMA), and collagen I were elevated by CCl₄ in comparison with the Sham. Upon CTC liposomal treatment, the quantitative score for the elevated fibrotic proteins such as TGFβ, α-SMA, and collagen I was normalized. CTC lipo displayed significant downregulation of the upregulated TGFβ, α-SMA, collagen I, and P-p38 expressions at the molecular level. The CXCR4 targeted liposomes showed prolonged biodistribution at 24 h. Our findings indicated that CTC lipo might be an alternative antifibrotic therapy that may offer new access to research and development. In a nutshell, the present study suggests that systemic administration of CTC lipo has efficient antifibrotic potential and deserves to be investigated for further clinical applications.

Topical Pirfenidone-Loaded Liposomes Ophthalmic Formulation Reduces Haze Development after Corneal Alkali Burn in Mice

Corneal chemical burns (CCBs) frequently result in corneal fibrosis or haze, an opacity of the cornea that obstructs vision and induces corneal blindness. Diverse strategies have been employed to prevent or reduce CCB-related corneal haze. In this study, we evaluated the physicochemical characteristics and biologic effects of a topical pirfenidone (PFD)-loaded liposomal formulation (PL) on a corneal alkali burn mice model. We found that PL was appropriate for ocular application due to its physiologic tear pH, osmolarity and viscosity suitable for topical ophthalmic use. Regarding its therapeutic activity, PL-treated mice had significantly reduced haze size and density, corneal edema, corneal thickness, and corneal inflammatory infiltration, in contrast to PFD in aqueous solution (p < 0.01). Importantly, the antifibrotic activity of PL (reduction of corneal haze) was associated with modulation of transforming growth factor (TGF)-β and Interleukin (IL)-1β genes. PL suppressed TGF-β expression and restored normal IL-1β expression in corneal tissue more efficiently in contrast to PFD in aqueous solution. In conclusion, PFD showed essential anti-inflammatory and anti-fibrotic effects in the treatment of alkali burns. Noteworthy, a new formulation of PFD-loaded liposomes remarkably improved these effects, standing out as a promising treatment for corneal haze.

Transcriptome analysis reveals the molecular mechanism of Yiqi Rougan decoction in reducing CCl4-induced liver fibrosis in rats

Background

Liver fibrosis develops from various chronic liver diseases, and there is currently a lack of specific treatment strategies. Yiqi Rougan decoction (YQRG) is a traditional Chinese medicine that has shown durative effects in the treatment of liver fibrosis; however, the mechanism associated with YQRG-related improvements in liver fibrosis remains to be experimentally determined. This study evaluated the therapeutic effect of YQRG on carbon tetrachloride (CCl₄)-induced liver fibrosis in rats and its molecular mechanism.

Methods

We used low-, medium-, and high-dose YQRG to treat CCl₄-induced liver fibrosis in rats, followed by assessment of liver injury and fibrosis according to liver appearance, body weight, liver mass index, histopathologic examination, and serum testing. Additionally, we performed transcriptome analysis using RNA-sequencing (RNA-seq) technology, including cluster, Gene Ontology (GO), and pathway analyses, to identify differentially expressed genes (DEGs), and protein and gene expression were detected by immunofluorescence (IFC), western blot and real-time quantitative PCR.

Results

The results showed that YQRG effectively alleviated CCl₄-induced liver injury and fibrosis in rats, including observations of improved liver function, decreased activity of hepatic stellate cells (HSCs), and decreased extracellular matrix (ECM) deposition. Moreover, we identified downregulated and upregulated DEGs in the model group relative to the control and YQRG-treated groups, with GO analysis revealing their enrichment in biological processes, such as endoplasmic reticulum stress (ERS), apoptosis, and autophagy. Furthermore, pathway analysis showed that YQRG treatment downregulated the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase/Akt (PI3K/AKT) signalling pathways and upregulated other signalling pathways, including those related to peroxisome proliferator-activated receptors(PPAR) and AMP-activated protein kinase(AMPK), with these findings subsequently verified experimentally.

Conclusion

These findings showed that YQRG improved CCl₄-induced liver fibrosis through multiple mechanisms and pathways, offering critical insight into the YQRG-related therapeutic mechanism and promoting further research into its potential application.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-021-00552-w.

Tumor Microenvironment Features and Chemoresistance in Pancreatic Ductal Adenocarcinoma: Insights into Targeting Physicochemical Barriers and Metabolism as Therapeutic Approaches

Currently, the median overall survival of PDAC patients rarely exceeds 1 year and has an overall 5-year survival rate of about 9%. These numbers are anticipated to worsen in the future due to the lack of understanding of the factors involved in its strong chemoresistance. Chemotherapy remains the only treatment option for most PDAC patients; however, the available therapeutic strategies are insufficient. The factors involved in chemoresistance include the development of a desmoplastic stroma which reprograms cellular metabolism, and both contribute to an impaired response to therapy. PDAC stroma is composed of immune cells, endothelial cells, and cancer-associated fibroblasts embedded in a prominent, dense extracellular matrix associated with areas of hypoxia and acidic extracellular pH. While multiple gene mutations are involved in PDAC initiation, this desmoplastic stroma plays an important role in driving progression, metastasis, and chemoresistance. Elucidating the mechanisms underlying PDAC resistance are a prerequisite for designing novel approaches to increase patient survival. In this review, we provide an overview of the stromal features and how they contribute to the chemoresistance in PDAC treatment. By highlighting new paradigms in the role of the stromal compartment in PDAC therapy, we hope to stimulate new concepts aimed at improving patient outcomes.

Total C-21 Steroidal Glycosides From Baishouwu Ameliorate Hepatic and Renal Fibrosis by Regulating IL-1β/MyD88 Inflammation Signaling

Fibrosis is a worldwide public health problem, which typically results from chronic diseases and often leads to organ malfunction. Chronic inflammation has been suggested to be the major trigger for fibrogenesis, yet mechanisms by which inflammatory signals drive fibrogenesis have not been fully elucidated. Total C-21 steroidal glycosides (TCSG) from Baishouwu are the main active components of the root of Cynanchum auriculatum Royle ex Wight, which exert hepatoprotective and anti-inflammation properties. In this study, we established a mouse model with the coexistence of hepatic and renal fibrosis and aimed to investigate the effects of TCSG from Baishouwu on fibrosis and explored the potential mechanisms. The results of biochemical and pathological examinations showed that TCSG from Baishouwu improved liver and kidney function and alleviated hepatic and renal fibrosis by reducing collagen and extracellular matrix deposition in bile duct ligation and unilateral ureteral occlusion (BDL&UUO) mice. According to network pharmacology analysis, the mechanisms underlying the effects of TCSG from Baishouwu on hepatic and renal fibrosis were associated with inflammatory response pathways, including “Signaling by interleukins”, “MAP kinase activation”, “MyD88 cascade initiated on plasma membrane”, and “Interleukin-1 family signaling”. Regression analysis and western blot results revealed that IL-1β/MyD88 inflammation signaling played an essential role in the anti-fibrotic effects of TCSG from Baishouwu. Further data displayed that TCSG from Baishouwu affected inflammatory response and extracellular matrix deposition via suppressing the activation of p38 MAPK/JNK and NF-κB p65 signaling cascades both in the liver and kidney of BDL&UUO mice. Thus, our findings suggest TCSG from Baishouwu as a natural regimen against hepatic and renal fibrosis and provide direct evidence that IL-1β/MyD88 signaling crucially contributes to hepatic and renal fibrosis and modulates liver-kidney crosstalk by maintaining tight control over inflammatory responses.

Hepatocarcinogenesis Prevention by Pirfenidone Is PPARγ Mediated and Involves Modification of Nuclear NF-kB p65/p50 Ratio

Targeted therapies for regulating processes such as inflammation, apoptosis, and fibrogenesis might modulate human HCC development. Pirfenidone (PFD) has shown anti-fibrotic and anti-inflammatory functions in both clinical and experimental studies. The aim of this study was to evaluate PPARγ expression and localization in samples of primary human tumors and assess PFD-effect in early phases of hepatocarcinogenic process. Human HCC tissue samples were obtained by surgical resection. Experimental hepatocarcinogenesis was induced in male Fischer-344 rats. TGF-β1 and α-SMA expression was evaluated as fibrosis markers. NF-kB cascade, TNFα, IL-6, and COX-2 expression and localization were evaluated as inflammation indicators. Caspase-3, p53, and PARP-1 were used as apoptosis markers, PCNA for proliferation. Finally, PPARα and PPARγ expression were evaluated to understand the effect of PFD on the activation of such pathways. PPARγ expression was predominantly localized in cytoplasm in human HCC tissue. PFD was effective to prevent histopathological damage and TGF-β1 and α-SMA overexpression in the experimental model. Anti-inflammatory effects of PFD correlate with diminished IKK and decrease in both IkB-phosphorylation/NF-kB p65 expression and p65-translocation into the nucleus. Pro-apoptotic PFD-induced effects are related with p53 expression, Caspase-3 p17 activation, and PARP-1-cleavage. In conclusion, PFD acts as a tumor suppressor by preventing fibrosis, reducing inflammation, and promoting apoptosis in MRHM.

Liver Fibrosis: Therapeutic Targets and Advances in Drug Therapy

Liver fibrosis is an abnormal wound repair response caused by a variety of chronic liver injuries, which is characterized by over-deposition of diffuse extracellular matrix (ECM) and anomalous hyperplasia of connective tissue, and it may further develop into liver cirrhosis, liver failure or liver cancer. To date, chronic liver diseases accompanied with liver fibrosis have caused significant morbidity and mortality in the world with increasing tendency. Although early liver fibrosis has been reported to be reversible, the detailed mechanism of reversing liver fibrosis is still unclear and there is lack of an effective treatment for liver fibrosis. Thus, it is still a top priority for the research and development of anti-fibrosis drugs. In recent years, many strategies have emerged as crucial means to inhibit the occurrence and development of liver fibrosis including anti-inflammation and liver protection, inhibition of hepatic stellate cells (HSCs) activation and proliferation, reduction of ECM overproduction and acceleration of ECM degradation. Moreover, gene therapy has been proved to be a promising anti-fibrosis method. Here, we provide an overview of the relevant targets and drugs under development. We aim to classify and summarize their potential roles in treatment of liver fibrosis, and discuss the challenges and development of anti-fibrosis drugs.

Drug Repurposing, an Attractive Strategy in Pancreatic Cancer Treatment: Preclinical and Clinical Updates

Pancreatic cancer (PC) is one of the deadliest malignancies worldwide, since patients rarely display symptoms until an advanced and unresectable stage of the disease. Current chemotherapy options are unsatisfactory and there is an urgent need for more effective and less toxic drugs to improve the dismal PC therapy. Repurposing of non-oncology drugs in PC treatment represents a very promising therapeutic option and different compounds are currently being considered as candidates for repurposing in the treatment of this tumor. In this review, we provide an update on some of the most promising FDA-approved, non-oncology, repurposed drug candidates that show prominent clinical and preclinical data in pancreatic cancer. We also focus on proposed mechanisms of action and known molecular targets that they modulate in PC. Furthermore, we provide an explorative bioinformatic analysis, which suggests that some of the PC repurposed drug candidates have additional, unexplored, oncology-relevant targets. Finally, we discuss recent developments regarding the immunomodulatory role displayed by some of these drugs, which may expand their potential application in synergy with approved anticancer immunomodulatory agents that are mostly ineffective as single agents in PC.

Fluorofenidone protects liver against inflammation and fibrosis by blocking the activation of NF-κB pathway

Despite the increasing understanding of the pathophysiology of hepatic fibrosis, the therapies to combat it remain inadequate. Fluorofenidone (AKF-PD) is a novel pyridone agent able to ameliorate hepatic fibrosis in an experimental hepatic fibrosis model induced by dimethylnitrosamine. However, the underlying mechanism remains to be further elucidated. In light of the critical role of the NF-κB pathway in inflammation and hepatic fibrosis, together with the preliminary finding that AKF-PD decreases the release of proinflammatory cytokines in the endotoxemia and unilateral ureteral occlusion model, the aim of this study was to explore whether AKF-PD exerts an antifibrotic effect in hepatic fibrosis by inhibiting inflammation and suppressing the activation of the NF-κB pathway in vivo and in vitro. To test this possibility, the effect of AKF-PD on hepatic fibrosis models induced by both carbon tetrachloride (CCL₄ ) and porcine serum (PS) was investigated. Our results showed that AKF-PD treatment ameliorated hepatic injury and fibrosis in both models. Furthermore, the administration of AKF-PD induced a robust anti-inflammatory reaction revealed by the downregulation of the proinflammatory cytokines as well as the suppression of the infiltration of inflammatory cells in the fibrotic liver. The analysis of the mechanism of action demonstrated that the attenuation of the production of proinflammatory cytokines and chemokines mediated by AKF-PD in vivo and in vitro were accompanied by the suppression in the activation of the NF-κB signaling pathway. In conclusion, AKF-PD might be considered as an antifibrotic agent attenuating hepatic inflammation and fibrosis potentially through the suppression of the NF-κB pathway.

Signaling Pathways Involved in Diabetic Renal Fibrosis

Diabetic kidney disease (DKD), as the most common complication of diabetes mellitus (DM), is the major cause of end-stage renal disease (ESRD). Renal interstitial fibrosis is a crucial metabolic change in the late stage of DKD, which is always considered to be complex and irreversible. In this review, we discuss the pathological mechanisms of diabetic renal fibrosis and discussed some signaling pathways that are closely related to it, such as the TGF-β, MAPK, Wnt/β-catenin, PI3K/Akt, JAK/STAT, and Notch pathways. The cross-talks among these pathways were then discussed to elucidate the complicated cascade behind the tubulointerstitial fibrosis. Finally, we summarized the new drugs with potential therapeutic effects on renal fibrosis and listed related clinical trials. The purpose of this review is to elucidate the mechanisms and related pathways of renal fibrosis in DKD and to provide novel therapeutic intervention insights for clinical research to delay the progression of renal fibrosis.

Pirfenidone modifies hepatic miRNAs expression in a model of MAFLD/NASH

miRNAs are involved in the development of metabolic associated fatty liver disease (MAFLD) and nonalcoholic steatohepatitis (NASH). We aimed to evaluate modifications by prolonged-release pirfenidone (PR-PFD) on key hepatic miRNAs expression in a MAFLD/NASH model. First, male C57BL/6J mice were randomly assigned into groups and fed with conventional diet (CVD) or high fat and carbohydrate diet (HFD) for 16 weeks. At the end of the eighth week, HFD mice were divided in two and only one half was treated with 300 mg/kg/day of PR-PFD mixed with food. Hepatic expression of miRNAs and target genes that participate in inflammation and lipid metabolism was determined by qRT-PCR and transcriptome by microarrays. Increased hepatic expression of miR-21a-5p, miR-34a-5p, miR-122-5p and miR-103-3p in MAFLD/NASH animals was reduced with PR-PFD. Transcriptome analysis showed that 52 genes involved in lipid and collagen biosynthesis and inflammatory response were downregulated in PR-PFD group. The expression of Il1b, Tnfa, Il6, Tgfb1, Col1a1, and Srebf1 were decreased in PR-PFD treated animals. MAFLD/NASH animals compared to CVD group showed modifications in gene metabolic pathways implicated in lipid metabolic process, inflammatory response and insulin resistance; PR-PFD reversed these modifications.

Synthesis and anti-fibrotic effects of santamarin derivatives as cytotoxic agents against hepatic stellate cell line LX2

Liver fibrosis is a final result of extensive deposition of extracellular matrix (ECM) and starts with the activation and proliferation of hepatic stellate cells (HSCs). Our previous study showed that eudesmane sesquiterpenoid santamarin had cytotoxicity against hepatic stellate cell line LX2 (HSC-LX2) with IC₅₀ values of 16.5 ± 0.7 μM. To explore the structure-activity relationships, twenty-six derivatives were synthesized by modifying the hydroxyl group, double-bond and unsaturated lactone. Cytotoxicity evaluation suggested that eight derivatives (6, 9, 13, 17, 20 and 25-27) increased activity against HSC-LX2. Especially, derivatives 17, 20 and 25 displayed obvious cytotoxicity with IC₅₀ values of 6.4 ± 0.4, 4.6 ± 0.1, and 3.5 ± 0.1 μM, which were 3 to 5-fold higher than santamarin. Preliminary mechanisms study revealed that the active compound 20 exhibited more than 8-fold and 6-fold enhancement of inhibitory effect on the deposition of human hyaluronic acid (HA) and human laminin (HL) with IC₅₀ values of 7.6 ± 0.6 and 3.3 ± 1.2 μM.

Fraxinellone alleviates kidney fibrosis by inhibiting CUG-binding protein 1-mediated fibroblast activation

Chronic Kidney Disease (CKD) is a serious threat to human health. In addition, kidney fibrosis is a key pathogenic intermediate for the progression of CDK. Moreover, excessive activation of fibroblasts is key to the development of kidney fibrosis and this process is difficult to control. Notably, fraxinellone is a natural compound isolated from Dictamnus dasycarpus and has a variety of pharmacological activities, including hepatoprotective, anti-inflammatory and anti-cancer effects. However, the effect of fraxinellone on kidney fibrosis is largely unknown. The present study showed that fraxinellone could alleviate folic acid-induced kidney fibrosis in mice in a dose dependent manner. Additionally, the results revealed that fraxinellone could effectively down-regulate the expression of CUGBP1, which was highly up-regulated in human and murine fibrotic renal tissues. Furthermore, expression of CUGBP1 was selectively induced by the Transforming Growth Factor-beta (TGF-β) through p38 and JNK signaling in kidney fibroblasts. On the other hand, downregulating the expression of CUGBP1 significantly inhibited the activation of kidney fibroblasts. In conclusion, these findings demonstrated that fraxinellone might be a new drug candidate and CUGBP1 could be a promising target for the treatment of kidney fibrosis.

Identification of hepatic fibrosis inhibitors through morphometry analysis of a hepatic multicellular spheroids model

A chronic, local inflammatory milieu can cause tissue fibrosis that results in epithelial-to-mesenchymal transition (EMT), endothelial-to-mesenchymal transition (EndMT), increased abundance of fibroblasts, and further acceleration of fibrosis. In this study, we aimed to identify potential mechanisms and inhibitors of fibrosis using 3D model-based phenotypic screening. We established liver fibrosis models using multicellular tumor spheroids (MCTSs) composed of hepatocellular carcinoma (HCC) and stromal cells such as fibroblasts (WI38), hepatic stellate cells (LX2), and endothelial cells (HUVEC) seeded at constant ratios. Through high-throughput screening of FDA-approved drugs, we identified retinoic acid and forskolin as candidates to attenuate the compactness of MCTSs as well as inhibit the expression of ECM-related proteins. Additionally, retinoic acid and forskolin induced reprogramming of fibroblast and cancer stem cells in the HCC microenvironment. Of interest, retinoic acid and forskolin had anti-fibrosis effects by decreasing expression of α-SMA and F-actin in LX2 cells and HUVEC cells. Moreover, when sorafenib was added along with retinoic acid and forskolin, apoptosis was increased, suggesting that anti-fibrosis drugs may improve tissue penetration to support the efficacy of anti-cancer drugs. Collectively, these findings support the potential utility of morphometric analyses of hepatic multicellular spheroid models in the development of new drugs with novel mechanisms for the treatment of hepatic fibrosis and HCCs.

Targeting the Stromal Pro-Tumoral Hyaluronan-CD44 Pathway in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignancies. Present-day treatments have not shown real improvements in reducing the high mortality rate and the short survival of the disease. The average survival is less than 5% after 5 years. New innovative treatments are necessary to curtail the situation. The very dense pancreatic cancer stroma is a barrier that impedes the access of chemotherapeutic drugs and at the same time establishes a pro-proliferative symbiosis with the tumor, thus targeting the stroma has been suggested by many authors. No ideal drug or drug combination for this targeting has been found as yet. With this goal in mind, here we have explored a different complementary treatment based on abundant previous publications on repurposed drugs. The cell surface protein CD44 is the main receptor for hyaluronan binding. Many malignant tumors show over-expression/over-activity of both. This is particularly significant in pancreatic cancer. The independent inhibition of hyaluronan-producing cells, hyaluronan synthesis, and/or CD44 expression, has been found to decrease the tumor cell's proliferation, motility, invasion, and metastatic abilities. Targeting the hyaluronan-CD44 pathway seems to have been bypassed by conventional mainstream oncological practice. There are existing drugs that decrease the activity/expression of hyaluronan and CD44: 4-methylumbelliferone and bromelain respectively. Some drugs inhibit hyaluronan-producing cells such as pirfenidone. The association of these three drugs has never been tested either in the laboratory or in the clinical setting. We present a hypothesis, sustained by hard experimental evidence, suggesting that the simultaneous use of these nontoxic drugs can achieve synergistic or added effects in reducing invasion and metastatic potential, in PDAC. A non-toxic, low-cost scheme for inhibiting this pathway may offer an additional weapon for treating pancreatic cancer.

Molecular Mechanisms of Obesity-Linked Cardiac Dysfunction: An Up-Date on Current Knowledge

Obesity is defined as excessive body fat accumulation, and worldwide obesity has nearly tripled since 1975. Excess of free fatty acids (FFAs) and triglycerides in obese individuals promote ectopic lipid accumulation in the liver, skeletal muscle tissue, and heart, among others, inducing insulin resistance, hypertension, metabolic syndrome, type 2 diabetes (T2D), atherosclerosis, and cardiovascular disease (CVD). These diseases are promoted by visceral white adipocyte tissue (WAT) dysfunction through an increase in pro-inflammatory adipokines, oxidative stress, activation of the renin-angiotensin-aldosterone system (RAAS), and adverse changes in the gut microbiome. In the heart, obesity and T2D induce changes in substrate utilization, tissue metabolism, oxidative stress, and inflammation, leading to myocardial fibrosis and ultimately cardiac dysfunction. Peroxisome proliferator-activated receptors (PPARs) are involved in the regulation of carbohydrate and lipid metabolism, also improve insulin sensitivity, triglyceride levels, inflammation, and oxidative stress. The purpose of this review is to provide an update on the molecular mechanisms involved in obesity-linked CVD pathophysiology, considering pro-inflammatory cytokines, adipokines, and hormones, as well as the role of oxidative stress, inflammation, and PPARs. In addition, cell lines and animal models, biomarkers, gut microbiota dysbiosis, epigenetic modifications, and current therapeutic treatments in CVD associated with obesity are outlined in this paper.

hsa-miR-4443 inhibits myocardial fibroblast proliferation by targeting THBS1 to regulate TGF-β1/α-SMA/collagen signaling in atrial fibrillation

Fibrosis caused by the increase in extracellular matrix in cardiac fibroblasts plays an important role in the occurrence and development of atrial fibrillation (AF). The aim of this study was to investigate the role of hsa-miR-4443 in AF, human cardiac fibroblast (HCFB) proliferation, and extracellular matrix remodeling. TaqMan Stem-loop miRNA assay was used to measure hsa-miR-4443 expression in patients with persistent AF (n=123) and healthy controls (n=100). Patients with AF were confirmed to have atrial fibrosis by late gadolinium enhancement. At the cellular level, after hsa-miR-4443 mimic and inhibitor were transfected with HCFBs, proliferation, apoptosis, migration, and invasion were analyzed. Lastly, hsa-miR-4443-targeted gene and transforming growth factor (TGF)-β1/α-SMA/collagen pathway were evaluated by dual-luciferase reporter assay and western blot, respectively. In patients with AF, hsa-miR-4443 decreased significantly and collagen metabolism level increased significantly. Logistic regression analysis showed that low hsa-miR-4443 level was a risk factor of AF (P<0.001). The receiver operating characteristic curve revealed that hsa-miR-4443 was useful for predicting AF (area under the curve: 0.828, sensitivity: 0.71, specificity: 0.78, P<0.001). In HCFBs, hsa-miR-4443 targeted thrombospondin-1 (THBS1) and downregulated TGF-β1/α-SMA/collagen pathway. The inhibition of hsa-miR-4443 expression promoted HCFB proliferation, migration, invasion, myofibroblast differentiation, and collagen production. The significant reduction of hsa-miR-4443 can be used as a biomarker for AF. hsa-miR-4443 protected AF by targeting THBS1 and regulated TGF-β1/α-SMA/collagen pathway to inhibit HCFB proliferation and collagen synthesis.

Liver Cancer: Therapeutic Challenges and the Importance of Experimental Models

Liver cancer is one of the main causes of death related to cancer worldwide; its etiology is related with infections by C or B hepatitis virus, alcohol consumption, smoking, obesity, nonalcoholic fatty liver disease, diabetes, and iron overload, among other causes. Several kinds of primary liver cancer occur, but we will focus on hepatocellular carcinoma (HCC). Numerous cellular signaling pathways are implicated in hepatocarcinogenesis, including YAP-HIPPO, Wnt-β-catenin, and nuclear factor-κB (NF-κB); these in turn are considered novel therapeutic targets. In this review, the role of lipid metabolism regulated by peroxisome proliferator-activated receptor gamma (PPARγ) in the development of HCC will also be discussed. Moreover, recent evidence has been obtained regarding the participation of epigenetic changes such as acetylation and methylation of histones and DNA methylation in the development of HCC. In this review, we provide detailed and current information about these topics. Experimental models represent useful tools for studying the different stages of liver cancer and help to develop new pharmacologic treatments. Each model in vivo and in vitro has several characteristics and advantages to offer for the study of this disease. Finally, the main therapies approved for the treatment of HCC patients, first- and second-line therapies, are described in this review. We also describe a novel option, pirfenidone, which due to its pharmacological properties could be considered in the future as a therapeutic option for HCC treatment.

Artemisinin and artemisinin derivatives as anti-fibrotic therapeutics

Fibrosis is a pathological reparative process that can occur in most organs and is responsible for nearly half of deaths in the developed world. Despite considerable research, few therapies have proven effective and been approved clinically for treatment of fibrosis. Artemisinin compounds are best known as antimalarial therapeutics, but they also demonstrate antiparasitic, antibacterial, anticancer, and anti-fibrotic effects. Here we summarize literature describing anti-fibrotic effects of artemisinin compounds in in vivo and in vitro models of tissue fibrosis, and we describe the likely mechanisms by which artemisinin compounds appear to inhibit cellular and tissue processes that lead to fibrosis. To consider alternative routes of administration of artemisinin for treatment of internal organ fibrosis, we also discuss the potential for more direct oral delivery of Artemisia plant material to enhance bioavailability and efficacy of artemisinin compared to administration of purified artemisinin drugs at comparable doses. It is our hope that greater understanding of the broad anti-fibrotic effects of artemisinin drugs will enable and promote their use as therapeutics for treatment of fibrotic diseases.

The Epithelial-to-Mesenchymal Transition as a Possible Therapeutic Target in Fibrotic Disorders

Fibrosis is a chronic and progressive disorder characterized by excessive deposition of extracellular matrix, which leads to scarring and loss of function of the affected organ or tissue. Indeed, the fibrotic process affects a variety of organs and tissues, with specific molecular background. However, two common hallmarks are shared: the crucial role of the transforming growth factor-beta (TGF-β) and the involvement of the inflammation process, that is essential for initiating the fibrotic degeneration. TGF-β in particular but also other cytokines regulate the most common molecular mechanism at the basis of fibrosis, the Epithelial-to-Mesenchymal Transition (EMT). EMT has been extensively studied, but not yet fully explored as a possible therapeutic target for fibrosis. A deeper understanding of the crosstalk between fibrosis and EMT may represent an opportunity for the development of a broadly effective anti-fibrotic therapy. Here we report the evidences of the relationship between EMT and multi-organ fibrosis, and the possible therapeutic approaches that may be developed by exploiting this relationship.

Pirfenidone attenuates gentamicin-induced acute kidney injury by inhibiting inflammasome-dependent NLRP3 pathway in rats

Acute kidney injury (AKI) is an abrupt and usually reversible decline in renal function. AKI is considered one of the main drawbacks of the use of gentamicin that critically limits its clinical use. In this study, pirfenidone, an oral antifibrotic drug, was given to rats (200 mg/kg, p.o., daily) for seven days alone before the initiation of gentamicin treatment and continued for seven days alongside daily gentamicin injections. In gentamicin group, gentamicin was given to Wistar rats (100 mg/kg, i.p., daily) for seven days to induce AKI. Pirfenidone managed to alleviate gentamicin-induced AKI by improving kidney function parameters including serum creatinine, blood urea nitrogen (BUN), proteinuria, relative kidney-to-body weight ratio and creatinine clearance. Pirfenidone decreased cytotoxicity induced by gentamicin by decreasing lactate dehydrogenase (LDH) activity and improving histologic picture of tubules and glomeruli. Pirfenidone also alleviated oxidative stress induced by gentamicin by reducing malondialdehyde (MDA) and elevating reduced glutathione (GSH). Pirfenidone prevented the upregulated inflammasome pathway markers in the kidney. It succeeded in decreasing toll like recpetor-4 (TLR4), nuclear factor-kappa B (NF-κB), nucleotide-binding oligomerization domain [NOD]-like pyrin domain containing protein 3 (NLRP3), caspase-1, interleukin-1β (IL-1β) and IL-18 levels. Additionally, Pirfenidone caused a decrease in macrophage infiltration displayed by reduction in renal monocyte chemoattractant protein-1 (MCP-1) levels. To sum up, pirfenidone can effectively mitigate gentamicin-induced AKI by inhibiting oxidative stress, macrophage infiltration and inflammasome-dependent NLRP3 pathway-induced inflammation.

Pathophysiology of atrial fibrillation and chronic kidney disease

Atrial fibrillation (AF) and chronic kidney disease (CKD) are closely related conditions with shared risk factors. The growing prevalence of both AF and CKD indicates that more patients will suffer from concurrent conditions. There are various complex interlinking mechanisms with important implications for the management of these patients. Furthermore, there is uncertainty regarding the use of oral anticoagulation (OAC) in AF and CKD that is reflected by a lack of consensus between international guidelines. Therefore, the importance of understanding the implications of co-existing AF and CKD should not be underestimated. In this review, we discuss the pathophysiology and association between AF and CKD, including the underlying mechanisms, risk of thrombo-embolic and bleeding complications, influence on stroke management, and evidence surrounding the use of OAC for stroke prevention.

Pirfenidone Is an Agonistic Ligand for PPARα and Improves NASH by Activation of SIRT1/LKB1/pAMPK

Nonalcoholic steatohepatitis (NASH) is recognized by hepatic lipid accumulation, inflammation, and fibrosis. No studies have evaluated the prolonged‐release pirfenidone (PR‐PFD) properties on NASH features. The aim of this study is to evaluate how PR‐PFD performs on metabolic functions, and provide insight on a mouse model of human NASH. Male C57BL/6J mice were fed with either normo diet or high‐fat/carbohydrate diet for 16 weeks and a subgroup also fed with PR‐PFD (300 mg/kg/day). An insulin tolerance test was performed at the end of treatment. Histological analysis, determination of serum hormones, adipocytokines measurement, and evaluation of proteins by western blot was performed. Molecular docking, in silico site‐directed mutagenesis, and in vitro experiments using HepG2 cultured cells were performed to validate PR‐PFD binding to peroxisome proliferator–activated receptor alpha (PPAR‐α), activation of PPAR‐α promoter, and sirtuin 1 (SIRT1) protein expression. Compared with the high‐fat group, the PR‐PFD‐treated mice displayed less weight gain, cholesterol, very low density lipoprotein and triglycerides, and showed a significant reduction of hepatic macrosteatosis, inflammation, hepatocyte ballooning, fibrosis, epididymal fat, and total adiposity. PR‐PFD restored levels of insulin, glucagon, adiponectin, and resistin along with improved insulin resistance. Noteworthy, SIRT1–liver kinase B1–phospho‐5′ adenosine monophosphate–activated protein kinase signaling and the PPAR‐α/carnitine O‐palmitoyltransferase 1/acyl‐CoA oxidase 1 pathway were clearly induced in high fat + PR‐PFD mice. In HepG2 cells incubated with palmitate, PR‐PFD induced activation and nuclear translocation of both PPARα and SIRT1, which correlated with increased SIRT1 phosphorylated in serine 47, suggesting a positive feedback loop between the two proteins. These results were confirmed with both synthetic PPAR‐α and SIRT1 activators and inhibitors. Finally, we found that PR‐PFD is a true agonist/ligand for PPAR‐α. Conclusions: PR‐PFD provided an anti‐steatogenic effect and protection for inflammation and fibrosis.

Pirfenidone prevents and reverses hepatic insulin resistance and steatohepatitis by polarizing M2 macrophages

Nonalcoholic steatohepatitis (NASH) is associated with lipotoxic liver injury, leading to insulin resistance, inflammation, and fibrosis. Despite its increased global incidence, very few promising treatments for NASH are available. Pirfenidone is an antifibrotic agent used to treat pulmonary fibrosis; it suppresses the pulmonary influx of T cells and macrophages. Here, we investigated the effect of pirfenidone in a mouse model of lipotoxicity-induced NASH via a high-cholesterol and high-fat diet. After 12 weeks of feeding, pirfenidone administration attenuated excessive hepatic lipid accumulation and peroxidation by reducing the expression of genes related to lipogenesis and fatty acid synthesis and enhancing the expression of those related to fatty acid oxidation. Flow cytometry indicated that pirfenidone reduced the number of total hepatic macrophages, particularly CD11c⁺CD206^-(M1)-type macrophages, increased the number of CD11c^-CD206⁺(M2)-type macrophages, and subsequently reduced T-cell numbers, which helped improve insulin resistance and steatohepatitis. Moreover, pirfenidone downregulated the lipopolysaccharide (LPS)-induced mRNA expression of M1 marker genes and upregulated IL-4-induced M2 marker genes in a dose-dependent manner in RAW264.7 macrophages. Importantly, pirfenidone reversed insulin resistance, hepatic inflammation, and fibrosis in mice with pre-existing NASH. These findings suggest that pirfenidone is a potential candidate for the treatment of NASH.

Artificial MicroRNA-Mediated Tgfbr2 and Pdgfrb Co-Silencing Ameliorates Carbon Tetrachloride-Induced Hepatic Fibrosis in Mice

Hepatic stellate cells (HSCs) are the primary cell type responsible for liver fibrogenesis. Transforming growth factor beta 1 (TGF-β1) and platelet-derived growth factor (PDGF) are key profibrotic cytokines that regulate HSC activation and proliferation with functional convergence. Dual RNA interference against their receptors may achieve therapeutic effects. A novel RNAi strategy based on HSC-specific GFAP promoter-driven and lentiviral-expressed artificial microRNAs (amiRNAs) was devised that consists of an microRNA-30a backbone and effective shRNAs against mouse Pdgfrβ and Tgfbr2. Then, its antifibrotic efficacy was tested in primary and cultured HSCs and in mice affected with carbon tetrachloride-induced hepatic fibrosis. The study shows that amiRNA-mediated Pdgfrβ and Tgfbr2 co-silencing inhibits HSC activation and proliferation. After recombinant lentiviral particles were delivered into the liver via tail-vein injection, therapeutic amiRNAs were preferentially expressed in HSCs and efficiently co-knocked down in situ Tgfbr2 and Pdgfrβ expression, which correlates with downregulated expression of target or effector genes of their signaling, which include Pai-1, P70S6K, and D-cyclins. amiRNA-based HSC-specific co-silencing of Tgfbr2 and Pdgfrβ significantly suppressed hepatic expression of fibrotic markers α-Sma and Col1a1, extracellular matrix regulators Mmps and Timp1, and phenotypically ameliorated liver fibrosis, as indicated by reductions in serum alanine aminotransferase activity, collagen deposition, and α-Sma-positive staining. The findings provide proof of concept for the use of amiRNA-mediated co-silencing of two profibrogenic pathways in liver fibrosis treatment and highlight the therapeutic potential of concatenated amiRNAs for gene therapy.

Current Approaches Including Novel Nano/Microtechniques to Reduce Silicone Implant-Induced Contracture with Adverse Immune Responses

Capsular contracture, which is the pathologic development of fibrous capsules around implants, is a major complication of reconstructive and aesthetic breast surgeries. Capsular contracture can cause implant failure with breast hardening, deformity, and severe pain. The exact mechanisms underlying this complication remain unclear. In addition, anaplastic large cell lymphoma is now widely recognized as a very rare disease associated with breast implants. Foreign body reactions are an inevitable common denominator of capsular contracture. A number of studies have focused on the associated immune responses and their regulation. The present article provides an overview of the currently available techniques, including novel nano/microtechniques, to reduce silicone implant-induced contracture and associated foreign body responses.

Targeting the cancer-associated fibroblasts as a treatment in triple-negative breast cancer

Increased collagen expression in tumors is associated with increased risk of metastasis, and triple-negative breast cancer (TNBC) has the highest propensity to develop distant metastases when there is evidence of central fibrosis. Transforming growth factor-β (TGF-β) ligands regulated by cancer-associated fibroblasts (CAFs) promote accumulation of fibrosis and cancer progression. In the present study, we have evaluated TNBC tumors with enhanced collagen to determine whether we can reduce metastasis by targeting the CAFs with Pirfenidone (PFD), an anti-fibrotic agent as well as a TGF-β antagonist. In patient-derived xenograft models, TNBC tumors exhibited accumulated collagen and activated TGF-β signaling, and developed lung metastasis. Next, primary CAFs were established from 4T1 TNBC homograft tumors, TNBC xenograft tumors and tumor specimens of breast cancer patients. CAFs promoted primary tumor growth with more fibrosis and TGF-β activation and lung metastasis in 4T1 mouse model. We then examined the effects of PFD in vitro and in vivo. We found that PFD had inhibitory effects on cell viability and collagen production of CAFs in 2D culture. Furthermore, CAFs enhanced tumor growth and PFD inhibited the tumor growth induced by CAFs by causing apoptosis in the 3D co-culture assay of 4T1 tumor cells and CAFs. In vivo, PFD alone inhibited tumor fibrosis and TGF-β signaling but did not inhibit tumor growth and lung metastasis. However, PFD inhibited tumor growth and lung metastasis synergistically in combination with doxorubicin. Thus, PFD has great potential for a novel clinically applicable TNBC therapy that targets tumor-stromal interaction.

Drug idiosyncrasy due to pirfenidone presenting as acute liver failure: Case report and mini-review of the literature

Idiosyncratic drug‐induced liver injury (DILI) is ranked among the top most common etiologies of acute liver failure (ALF). It carries poor transplant‐free survival. Pirfenidone is an anti‐inflammatory and antifibrotic drug that is commonly used for the treatment of idiopathic pulmonary fibrosis (IPF). Hepatotoxicity due to pirfenidone is rare and generally manifests as a mild rise in serum aminotransferases. In this mini‐review, we report an unusual case of idiosyncratic DILI due to pirfenidone presenting as ALF, with emphasis on the definition, classification, diagnostic criteria, histopathology, molecular markers, and treatment options for DILI and related ALF. A 77‐year‐old man with known Parkinson's disease and IPF presented with jaundice for 7 days and altered mental status for 4 days. His long‐term medications included a levodopa/carbidopa combination with a recent addition of pirfenidone over the previous 1 month; there was no monitoring of liver function tests. The evaluation suggested features of acute liver failure with grade III hepatic encephalopathy, acute kidney injury, and metabolic acidosis. The diagnostic workup ruled out viral, toxic, ischemic, and other etiologies for acute liver failure. Based on a Roussel Uclaf Causality Assessment Method score of 7 and possible DILI‐ALF, pirfenidone was withdrawn. He was evaluated for liver transplantation but was declined. Despite all supportive measures in intensive care, organ failure progressed and he succumbed to the illness on day 4. Postmortem liver biopsy revealed findings consistent with DILI (final Roussel Uclaf Causality Assessment score, 10). Conclusion: DILI‐ALF carries poor prognosis, and liver transplantation should be considered early in the course. Characterization, reporting, monitoring, and labeling of pirfenidone‐related hepatotoxicity is vital given its common use in IPF. (Hepatology Communications 2018;2:142–147)

Effects of pirfenidone in acute and sub-chronic liver fibrosis, and an initiation-promotion cancer model in the mouse

Liver fibrosis results from chronic tissue damage and excessive regeneration with accumulation of extracellular matrix proteins; it is a precursor of liver cirrhosis and hepatocellular carcinoma. Liver fibrosis treatments are primarily directed at inflammation, with few options to combat fibrogenesis. Pirfenidone is a drug approved for idiopathic pulmonary fibrosis and this study was focused on anti-fibrotic and anti-cancer potential of pirfenidone in the liver of male B6C3F1/J mice. In a dose-finding study, mice were treated with CCl₄ (0.2ml/kg ip, 2×wk for 4weeks) while on a pirfenidone-containing (0-600mg/kg) diet. Pirfenidone at doses of 300 and 600mg/kg had significant anti-fibrotic (collagen) and anti-inflammatory (serum transaminases and "ballooning" hepatocyte) effects. In a sub-chronic study (14weeks), mice received CCl₄ while on pirfenidone (300mg/kg) diet. Pirfenidone significantly reduced collagen deposition, but had little effect of inflammation and injury. In an initiation-promotion cancer study with N-nitrosodiethylamine and CCl₄, pirfenidone (300mg/kg) did not affect incidence, size, or multiplicity of liver tumors. Overall, we conclude that while pirfenidone exhibits strong anti-fibrotic effects in early stage liver fibrosis, it is less effective in advanced liver fibrosis and was not protective in an initiation-promotion liver cancer.

Mechanisms of plasminogen activator inhibitor 1 action in stromal remodeling and related diseases

Plasminogen activator inhibitor type 1 (PAI-1) is the main physiologic inhibitor of fibrinolysis. However, it is also involved in many physiological processes such as extracellular matrix (ECM) proteolysis and remodeling, cell adhesion, motility, and apoptosis, angiogenesis, etc. The aim of the study was to summarize current knowledge and gain insights into the mechanisms of PAI-1 action in the processes of stromal remodeling and diseases with considerable matrix pathologies (atherosclerosis, tissue fibrosis, cancer metastasis, pregnancy related complications, etc). As a component of an early cellular response to injury, PAI-1 reacts with membrane surface proteins and participates in the initiation of intracellular signaling, specifically cytoskeletal reorganization and motility. Complexity of ECM homeostasis resides in varying relation of the plasminogen system components and other matrix constituents. Inflammatory mediators (transforming growth factor-β and interferon-γ) and hormones (angiotensin II) are in the close interdependent relation with PAI-1. Also, special attention is devoted to the role of increased PAI-1 concentrations due to the common 4G/5G polymorphism. Some of the novel mechanisms of ECM modification consider PAI-1 dependent stabilization of urokinase mediated cell adhesion, control of the vascular endothelial cadherin trafficking and interaction with endothelial cells proteasome, its relation to matrix metalloproteinase 2 and osteopontin, and oxidative inhibition by myeloperoxidase. Targeting and/or alteration of PAI-1 functions might bring benefit to the future therapeutic approaches in diseases where ECM undergoes substantial remodeling.

Pirfenidone may revert the epithelial-to-mesenchymal transition in human lung adenocarcinoma

The epithelial-to-mesenchymal transition (EMT) in cancer is associated with invasion, metastasis and chemoresistance. Recent studies have revealed the increased expression of programmed death-ligand 1 (PD-L1) in cells undergoing EMT. The underlying mechanism of EMT involves transforming growth factor-β (TGF-β) and fibroblast growth factor-2 (FGF-2). Pirfenidone and the known EMT-suppressor nintedanib suppress pulmonary fibrosis partially through suppression of TGF-β. The present study aimed to determine whether pirfenidone has the potential to induce EMT-reversion, using nintedanib as a reference. The human lung adenocarcinoma cell lines A-549, HCC-827, and PC-9 were treated with TGF-β and FGF-2 to induce EMT. The EMT-induced cells were further treated with pirfenidone or nintedanib. Phenotypic alterations associated with EMT were assessed by examining the following: i) The expression levels of E-cadherin, vimentin, fibronectin and slug, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and fluorescent immunohistochemistry; ii) cell motility via wound-healing assays; and iii) the expression of PD-L1 using RT-qPCR. The combination of TGF-β and FGF-2 successfully induced EMT in all three cell lines, characterized by a significant reduction in E-cadherin expression in the A-549 and HCC-827 cells, increased expression levels of vimentin, fibronectin, slug and PD-L1, and increased cell motility in all three cell lines. Pirfenidone and nintedanib reverted all of these phenotypes, with the exception of unaltered E-cadherin expression in all three cell lines, and inconsistent expression of vimentin in the HCC-827 and PC-9 cells. Thus, pirfenidone and nintedanib have the ability to induce EMT-reversion in human lung adenocarcinoma.

Antifibrotic effect of pirfenidone in a mouse model of human nonalcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is characterized by steatosis with lobular inflammation and hepatocyte injury. Pirfenidone (PFD) is an orally bioavailable pyridone derivative that has been clinically used for the treatment of idiopathic pulmonary fibrosis. However, it remains unknown whether PFD improves liver fibrosis in a mouse model with human NASH-like phenotypes. In this study, we employed melanocortin 4 receptor-deficient (MC4R-KO) mice as a mouse model with human NASH-like phenotypes to elucidate the effect and action mechanisms of PFD on the development of NASH. PFD markedly attenuated liver fibrosis in western diet (WD)-fed MC4R-KO mice without affecting metabolic profiles or steatosis. PFD prevented liver injury and fibrosis associated with decreased apoptosis of liver cells in WD-fed MC4R-KO mice. Pretreatment of PFD inhibited the tumor necrosis factor-α (TNF-α)-induced liver injury and fibrogenic responses associated with decreased apoptosis of liver cells in wild-type mice. PFD also prevented TNF-α-induced hepatocyte apoptosis in vitro with reduced activation of caspase-8 and -3. This study provides evidence for the antifibrotic effect of PFD in a mouse model of human NASH. The data of this study highlight hepatocyte apoptosis as a potential therapeutic target, and suggest that PFD can be repositioned as an antifibrotic drug for human NASH.

Pirfenidone for the treatment of idiopathic pulmonary fibrosis

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a diffuse parenchymal lung disease with no cure. Up until recently, no treatment had been proven to alter its natural history as judged by rate of lung function decline. In 2014 however, the emergence of two novel anti-fibrotic agents, Pirfenidone and Nintedanib revolutionized the management of this condition. Both have demonstrated the ability to deliver a major reduction in the rate of chronic IPF progression. Areas Covered: This review article focuses on Pirfenidone - a pyridone derivative initially designed as an analgesic and anti-pyretic agent. Here we describe the history of the drug from its inception through to exploratory pre-clinical in-vitro and in-vivo studies where its anti-fibrotic potential was identified, and eventually to large multicenter randomized controlled trials. Expert Commentary: This article also summarizes some of the difficulties surrounding clinical end-point selection in IPF trials and addresses some of the challenges facing the IPF community over the coming years.

Management strategies for liver fibrosis

Liver fibrosis resulting from chronic liver injury are major causes of morbidity and mortality worldwide. Among causes of hepatic fibrosis, viral infection is most common (hepatitis B and C). In addition, obesity rates worldwide have accelerated the risk of liver injury due to nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Also liver fibrosis is associated with the consumption of alcohol, or autoimmune hepatitis and chronic cholangiophaties. The response of hepatocytes to inflammation plays a decisive role in the physiopathology of hepatic fibrosis, which involves the recruitment of both pro- and anti-inflammatory cells such as monocytes and macrophages. As well as the production of other cytokines and chemokines, which increase the stimulus of hepatic stellate cells by activating proinflammatory cells. The aim of this review is to identify the therapeutic options available for the treatment of the liver fibrosis, enabling the prevention of progression when is detected in time.

The Relationship between Serum Bilirubin and Elevated Fibrotic Indices among HBV Carriers: A Cross-Sectional Study of a Chinese Population

The study probed the association between bilirubin and hepatitis B virus (HBV) infection and progression. A cross-sectional analysis of 28,500 middle aged and elderly Chinese participants was performed to analyze the differences of bilirubin in terms of hepatitis B surface antigen (HBsAg) positive or negative and the correlation between bilirubin and severity of hepatic fibrosis estimated by non-invasive indices. Bilirubin was significantly higher in the HBsAg (+) group than the HBsAg (−) group. Higher bilirubin levels were consistently associated with elevated liver fibrosis indices among HBsAg carriers. Compared with quartile 1 of total bilirubin (TBil), the multivariable-adjusted ORs (95% CIs) for elevated fibrosis indices of quartile 4 were 2.24 (95% CIs, 1.57–3.21) estimated by fibrosis 4 score (FIB-4) and 2.22 (95% CIs, 1.60–3.08) estimated by aspartate transaminase to platelet ratio index (APRI). In addition, direct bilirubin (DBil) had a stronger association with elevated liver fibrosis indices than did indirect bilirubin (IBil). Furthermore, the relationship between DBil and elevated fibrosis indices was more robust among participants who were female, overweight or had central fat distribution. These findings suggested that bilirubin levels, especially DBil, were independently associated with an increased risk of increased fibrosis indices.

Pirfenidone exerts a suppressive effect on CCL18 expression in U937-derived macrophages partly by inhibiting STAT6 phosphorylation

CONTEXT

CC chemokine ligand 18 (CCL18) is suggested to play a role in the development of pulmonary fibrosis. Macrophages are thought to be the main source of CCL18, and the effect of pirfenidone, an anti-fibrotic agent for idiopathic pulmonary fibrosis, on the expression of CCL18 in macrophages warrants investigation.

OBJECTIVE

The purpose of this study was to investigate the effect of pirfenidone on the expression of CCL18 in macrophages.

MATERIALS AND METHODS

U937 cells were differentiated into macrophages by phorbol myristate acetate and then stimulated with recombinant IL-4 to induce the production of CCL18. The cells were treated with pirfenidone, and the mRNA and protein levels for CCL18 were measured by a reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The effects of pirfenidone on the IL-4 receptor (IL-4R) expression and STAT6 activation were investigated and on the JAK kinase activity were measured using the Z'-LYTE™ kinase assay.

RESULTS

Pirfenidone significantly suppressed the expression of CCL18 when the cells were treated with concentrations of 50-250 μg/mL. Pirfenidone did not affect the expression of the IL-4R components. The selective STAT6 inhibitor AS1517499 suppressed CCL18 expression. Both AS1517499 and pirfenidone suppressed STAT6 phosphorylation (p < .05), although the effect of pirfenidone was less marked than that of AS1517499. The Z'-LYTE™ kinase assay showed a reduction in the activities of JAK1, JAK3 and TYK2 by pirfenidone.

CONCLUSION

Pirfenidone suppresses CCL18 expression in macrophages and this effect is thought to be attributed partly to the inhibition of STAT6 phosphorylation.

Pirfenidone ameliorates concanavalin A-induced hepatitis in mice via modulation of reactive oxygen species/nuclear factor kappa B signalling pathways

Objectives

This study aimed to evaluate the potential protective effects of pirfenidone (PFD) against concanavalin A (Con A)-induced hepatitis in mice.

Methods

Autoimmune model of hepatitis was established using single intravenous injection of Con A. Mice were randomly assigned into four groups as follows: control group; Con A group; and two groups, receiving PFD in two dose levels (200, 300 mg/kg) for 5 days before Con A administration. Extent of hepatitis was studied using biochemical, histopathological and immunohistochemical estimations.

Key findings

Hepatitis was clearly evident through extensive hepatocellular lesions and elevated levels of serum transaminases, alkaline phosphatase and lactate dehydrogenase. Con A induced an imbalance between oxidant and antioxidant status in the hepatic tissue. Furthermore, Con A significantly elevated hepatic nuclear factor kappa B (NF-κB) expression and inflammatory cytokines levels (tumour necrosis factor-alpha, interleukin-6 and nitric oxide). PFD pretreatment potently ameliorated all these pathological changes.

Conclusions

Pirfenidone hepatoprotective activity may be mediated through its antioxidant ability that suppresses NF-κB activation signalling pathways suggesting that PFD may be a new candidate for treatment of acute hepatitis.