Inhibitory effect of tanshinone IIA on rat hepatic stellate cells

The nanocrystal-loaded liposome of tanshinone IIA with high drug loading and stability towards efficient liver fibrosis reversion

Tanshinone IIA (TSIIA) is a lipid-soluble pharmacological constituent extracted from the Salvia miltiorrhiza with anti-hepatic fibrosis properties. However, its clinical use has been limited due to its poor water solubility and oral bioavailability. In this paper, we constructed a drug delivery system consisting of a drug nanocrystal core and a liposome shell: TSIIA nanocrystals@liposome (TNC@Lipo). This combination can greatly improve the solubility and bioavailability of poorly water-soluble drugs. TNC@Lipo was prepared by ultrasonic method combined with antisolvent method. In order to obtain the optimal TNC, we optimized the formulation ratio and preparation process of TNC by single-factor experiments. The results showed that TNC@Lipo had higher drug loading (27.86 ± 1.55 %) and superior stability. And TNC@Lipo can significantly reversed CCl4-induced liver fibrosis in mice compared with free-TSIIA. In conclusion, this study provides a new approach for the clinical application of TSIIA.

[18F]AlF-ND-bisFAPI PET imaging of fibroblast activation protein as a biomarker to monitor the progression of liver fibrosis

BACKGROUND

Hepatic fibrosis is a progressive disease, which is reversible in the early stages. The current monitoring methods have notable limitations that pose a challenge to early detection. In this study, we evaluated the utility of [18F]AlF-ND-bisFAPI positron emission tomography imaging of fibroblast activation protein (FAP) to monitor the progression of liver fibrosis.

METHODS

Two mouse models of liver fibrosis were established by bile duct ligation and carbon tetrachloride administration, respectively. Positron emission tomography imaging was performed with the FAP-specific radiotracer [18F]AlF-ND-bisFAPI for the evaluation of rat HSCs and mouse models of fibrosis and combined with histopathology, immunohistochemical staining, and immunoblotting to elucidate the relationships among radioactivity uptake, FAP levels, and liver fibrosis progression. Furthermore, [18F]AlF-ND-bisFAPI autoradiography was performed to assess tracer binding in liver sections from patients with varying degrees of liver fibrosis.

RESULTS

Cell experiments demonstrated that [18F]AlF-ND-bisFAPI uptake was specific in activated HSCs. Compared with control mice, [18F]AlF-ND-bisFAPI uptake in livers increased in the early stages of fibrosis and increased significantly further with disease progression. Immunohistochemistry and western blot analyses demonstrated that FAP expression increased with fibrosis severity. In accordance with the findings in animal models, ex vivo autoradiography on human fibrotic liver sections showed that radioactivity increased as fibrosis progressed from mild to severe.

CONCLUSIONS

[18F]AlF-ND-bisFAPI positron emission tomography imaging is a promising noninvasive method for monitoring the progression of liver fibrosis.

Extracellular matrix turnover: phytochemicals target and modulate the dual role of matrix metalloproteinases (MMPs) in liver fibrosis

Extracellular matrix (ECM) resolution by matrix metalloproteinases (MMPs) is a well-documented mechanism. MMPs play a dual and complex role in modulating ECM degradation at different stages of liver fibrosis, depending on the timing and levels of their expression. Increased MMP-1 combats disease progression by cleaving the fibrillar ECM. Activated hepatic stellate cells (HSCs) increase expression of MMP-2, -9, and -13 in different chemicals-induced animal models, which may alleviate or worsen disease progression based on animal models and the stage of liver fibrosis. In the early stage, elevated expression of certain MMPs may damage surrounding tissue and activate HSCs, promoting fibrosis progression. At the later stage, downregulation of MMPs can facilitate ECM accumulation and disease progression. A number of phytochemicals modulate MMP activity and ECM turnover, alleviating disease progression. However, the effects of phytochemicals on the expression of different MMPs are variable and may depend on the disease models and stage, and the dosage, timing and duration of phytochemicals used in each study. Here, we review the most recent advances in the role of MMPs in the effects of phytochemicals on liver fibrogenesis, which indicates that further studies are warranted to confirm and define the potential clinical efficacy of these phytochemicals.

Therapeutic prospects of naturally occurring p38 MAPK inhibitors tanshinone IIA and pinocembrin for the treatment of SARS-CoV-2-induced CNS complications

P38 mitogen-activated protein kinase (p38 MAPK) signaling pathway is closely related to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) replication and hyperinflammatory responses in coronavirus disease 2019 (COVID-19). Therefore, blood-brain barrier-penetrating p38 MAPK inhibitors have good potential for the treatment of central nervous system (CNS) complications of COVID-19. The aim of the present study is the characterization of the therapeutic potential of tanshinone IIA and pinocembrin for the treatment of CNS complications of COVID-19. Studies published in high-quality journals indexed in databases Scopus, Web of Science, PubMed, and so forth were used to review the therapeutic capabilities of selected compounds. In continuation of our previous efforts to identify agents with favorable activity/toxicity profiles for the treatment of COVID-19, tanshinone IIA and pinocembrin were identified with a high ability to penetrate the CNS. Considering the nature of the study, no specific time frame was determined for the selection of studies, but the focus was strongly on studies published after the emergence of COVID-19. By describing the association of COVID-19-induced CNS disorders with p38 MAPK pathway disruption, this study concludes that tanshinone IIA and pinocembrin have great potential for better treatment of these complications. The inclusion of these compounds in the drug regimen of COVID-19 patients requires confirmation of their effectiveness through the conduction of high-quality clinical trials.

Formulation and Evaluation on Synergetic Anti-Hepatoma Effect of a Chemically Stable and Release-Controlled Nanoself-Assembly with Natural Monomers

Introduction

Hepatoma is the leading cause of death among liver diseases worldwide. Modern pharmacological studies suggest that some natural monomeric compounds have a significant effect on inhibiting tumor growth. However, poor stability and solubility, and side effects are the main factors limiting the clinical application of natural monomeric compounds.

Methods

In this paper, drug-co-loaded nanoself-assemblies were selected as a delivery system to improve the chemical stability and solubility of Tanshinone II A and Glycyrrhetinic acid, and to produce a synergetic anti-hepatoma effect.

Results

The study suggested that the drug co-loaded nanoself-assemblies showed high drug loading capacity, good physical and chemical stability, and controlled release. In vitro cell experiments verified that the drug-co-loaded nanoself-assemblies could increase the cellular uptake and cell inhibitory activity. In vivo studies verified that the drug co-loaded nanoself-assemblies could prolong the MRT_0-∞, increase accumulation in tumor and liver tissues, and show strong synergistic anti-tumor effect and good bio-safety in H22 tumor-bearing mice.

Conclusion

This work indicates that natural monomeric compounds co-loaded nanoself-assemblies would be a potential strategy for the treatment of hepatoma.

Tanshinone IIA and hepatocellular carcinoma: A potential therapeutic drug

Because of its high prevalence and poor long-term clinical treatment effect, liver disease is regarded as a major public health problem around the world. Among them, viral hepatitis, fatty liver, cirrhosis, non-alcoholic fatty liver disease (NAFLD), and autoimmune liver disease are common causes and inducements of liver injury, and play an important role in the occurrence and development of hepatocellular carcinoma (HCC). Tanshinone IIA (TsIIA) is a fat soluble polyphenol of Salvia miltiorrhiza that is extracted from Salvia miltiorrhiza. Because of its strong biological activity (anti-inflammatory, antioxidant), it is widely used in Asia to treat cardiovascular and liver diseases. In addition, TsIIA has shown significant anti-HCC activity in previous studies. It not only has significant anti proliferation and pro apoptotic properties. It can also play an anti-cancer role by mediating a variety of signal pathways, including phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/rapamycin (mTOR), mitogen-activated protein kinase (MAPK), and nuclear factor kappa-B (NF-κB). This review not only reviews the existing evidence and molecular mechanism of TsIIA's anti-HCC effect but also reviews the liver-protective effect of TsIIA and its impact on liver fibrosis, NAFLD, and other risk factors for liver cancer. In addition, we also conducted network pharmacological analysis on TsIIA and HCC to further screen and explore the possible targets of TsIIA against hepatocellular carcinoma. It is expected to provide a theoretical basis for the development of anti-HCC-related drugs based on TsIIA.

Endotoxemia and Gastrointestinal Cancers: Insight into the Mechanisms Underlying a Dangerous Relationship

Lipopolysaccharide (LPS), also known as endotoxin, is a component of the membrane of gram-negative bacteria and a well-recognized marker of sepsis. In case of disruption of the intestinal barrier, as occurs with unhealthy diets, alcohol consumption, or during chronic diseases, the microbiota residing in the gastrointestinal tract becomes a crucial factor in amplifying the systemic inflammatory response. Indeed, the translocation of LPS into the bloodstream and its interaction with toll-like receptors (TLRs) triggers molecular pathways involved in cytokine release and immune dysregulation. This is a critical step in the exacerbation of many diseases, including metabolic disorders and cancer. Indeed, the role of LPS in cancer development is widely recognized, and examples include gastric tumor related to Helicobacter pylori infection and hepatocellular carcinoma, both of which are preceded by a prolonged inflammatory injury; in addition, the risk of recurrence and development of metastasis appears to be associated with endotoxemia. Here, we review the mechanisms that link the promotion and progression of tumorigenesis with endotoxemia, and the possible therapeutic interventions that can be deployed to counteract these events.

Traditional Chinese medicine: An important source for discovering candidate agents against hepatic fibrosis

Hepatic fibrosis (HF) refers to the pathophysiological process of connective tissue dysplasia in the liver caused by various pathogenic factors. Nowadays, HF is becoming a severe threat to the health of human being. However, the drugs available for treating HF are limited. Currently, increasing natural agents derived from traditional Chinese medicines (TCMs) have been found to be beneficial for HF. A systemic literature search was conducted from PubMed, GeenMedical, Sci-Hub, CNKI, Google Scholar and Baidu Scholar, with the keywords of "traditional Chinese medicine," "herbal medicine," "natural agents," "liver diseases," and "hepatic fibrosis." So far, more than 76 natural monomers have been isolated and identified from the TCMs with inhibitory effect on HF, including alkaloids, flavones, quinones, terpenoids, saponins, phenylpropanoids, and polysaccharides, etc. The anti-hepatic fibrosis effects of these compounds include hepatoprotection, inhibition of hepatic stellate cells (HSC) activation, regulation of extracellular matrix (ECM) synthesis & secretion, regulation of autophagy, and antioxidant & anti-inflammation, etc. Natural compounds and extracts from TCMs are promising agents for the prevention and treatment of HF, and this review would be of great significance to development of novel drugs for treating HF.

Salvia miltiorrhiza Bge. (Danshen) in the Treating Non-alcoholic Fatty Liver Disease Based on the Regulator of Metabolic Targets

Non-alcoholic fatty liver disease (NAFLD) is rapidly prevalent due to its strong association with increased metabolic syndrome such as cardio- and cerebrovascular disorders and diabetes. Few drugs can meet the growing disease burden of NAFLD. Salvia miltiorrhiza Bge. (Danshen) have been used for over 2,000 years in clinical trials to treat NAFLD and metabolic syndrome disease without clarified defined mechanisms. Metabolic targets restored metabolic homeostasis in patients with NAFLD and improved steatosis by reducing the delivery of metabolic substrates to liver as a promising way. Here we systematic review evidence showing that Danshen against NAFLD through diverse and crossing mechanisms based on metabolic targets. A synopsis of the phytochemistry and pharmacokinetic of Danshen and the mechanisms of metabolic targets regulating the progression of NAFLD is initially provided, followed by the pharmacological activity of Danshen in the management NAFLD. And then, the possible mechanisms of Danshen in the management of NAFLD based on metabolic targets are elucidated. Specifically, the metabolic targets c-Jun N-terminal kinases (JNK), sterol regulatory element-binding protein-1c (SREBP-1c), nuclear translocation carbohydrate response element–binding protein (ChREBP) related with lipid metabolism pathway, and peroxisome proliferator-activated receptors (PPARs), cytochrome P450 (CYP) and the others associated with pleiotropic metabolism will be discussed. Finally, providing a critical assessment of the preclinic and clinic model and the molecular mechanism in NAFLD.

Lipophilic Constituents in Salvia miltiorrhiza Inhibit Activation of the Hepatic Stellate Cells by Suppressing the JAK1/STAT3 Signaling Pathway: A Network Pharmacology Study and Experimental Validation

Liver fibrosis is currently a global health challenge with no approved therapy, with the activation of hepatic stellate cells being a principal factor. Lipophilic constituents in Salvia miltiorrhiza (LS) have been reported to improve liver function and reduce the indicators of liver fibrosis for patients with chronic hepatitis B induced hepatic fibrosis. However, the pharmacological mechanisms of LS on liver fibrosis have not been clarified. In this study, 71 active compounds, 342 potential target proteins and 22 signaling pathways of LS were identified through a network pharmacology strategy. Through text mining and data analysis, the JAK1/STAT3 signaling pathway was representatively selected for further experimental validation. We firstly confirmed the protective effect of LS on liver fibrosis in vivo by animal experiments. Hepatic stellate cells, which proliferated and displayed a fibroblast-like morphology similar to activated primary stellate cells, were applied to evaluate its underlying mechanisms. The results showed that LS could inhibit the cell viability, promote the cell apoptosis, decrease the expression of liver fibrosis markers, and downregulate the JAK1/STAT3 signaling pathway. These results demonstrated that LS could exert anti-liver-fibrosis effects by inhibiting the activation of HSCs and regulating the JAK1/STAT3 signaling pathway, which is expected to benefit its clinical application.

Tanshinone IIA alleviate rifampicin-induced cholestasis by regulating the expression and function of bile salt export pump

Objective: Rifampicin (RFP) induces cholestasis due to long-term tubercular therapy. Impairment of the canalicular bile acids efflux via the bile salt export pump (BSEP) is a well-recognized cause of cholestasis. Tanshinone IIA (TAN IIA) has a protective effect on the liver. However, there are limited studies on the effects of RFP and TAN IIA on BSEP. In present study, we aimed to elucidate the effects of RFP and TAN IIA on BSEP and provide evidence to support the treatment of RFP-induced cholestasis with TAN IIA. Methods: Firstly, liver histopathological examination and serum biochemical tests were evaluated in rats. Secondly, we evaluated BSEP expression by qRT-PCR and western blotting to explore whether RFP and TAN IIA influence liver function through BSEP. Thirdly, the accumulation of BSEP substrate taurocholic acid (TCA) in bile ducts was determined to investigate the effects of RFP and TAN IIA on BSEP function. Results: Apparent histopathological alterations and significantly increased serum biomarkers were observed in the RFP group (200 mg/kg), while these changes were attenuated in the combination groups. The mRNA and protein levels of BSEP were decreased by RFP. Whereas TAN IIA reversed the downward regulation of BSEP caused by RFP. And RFP primarily inhibited TCA excretion but co-administration of TAN IIA markedly induced TCA excretion mediated by BSEP. Conclusion: Our findings collectively demonstrated that RFP-induced cholestasis could be related to the inhibition of BSEP, and TAN IIA had the potential to prevent RFP-induced cholestasis by regulating BSEP.

Modified Lipid Nanocapsules for Targeted Tanshinone IIA Delivery in Liver Fibrosis

Introduction

Liver fibrosis represents a serious global disease with no approved treatment. Tanshinone IIA (TSIIA) is a phytomedicine with documented activity in treating many hepatic disorders. TSIIA has been reported to have potent anti-inflammatory and antioxidant properties. It can also induce apoptosis for activated hepatic stellate cells, and is thereby considered as a promising herbal remedy for treating fibrotic liver. However, its poor aqueous solubility, short half-life, exposure to the first-pass effect, and low concentration reaching targeted cells constitute the major barriers hindering its effective therapeutic potential. Therefore, this work aimed at enhancing TSIIA systemic bioavailability together with achieving active targeting potential to fibrotic liver via its incorporation into novel modified lipid nanocapsules (LNCs).

Methods

Blank and TSIIA-loaded LNCs modified with either hyaluronate sodium or phosphatidyl serine were successfully prepared, optimized, and characterized both in vitro and in vivo.

Results

The developed LNCs showed good colloidal properties (size ≤100 nm and PDI ≤0.2), high drug-entrapment efficiency (>97%) with sustained-release profile for 24 hours, high storage stability up to 6 months, and good in vitro serum stability. After a single intraperitoneal injection, the administered LNCs exhibited a 2.4-fold significant increase in AUC_0–∞ compared with the TSIIA suspension (p≤0.01). Biodistribution-study results proved the liver-targeting ability of the prepared modified LNCs, with a significant ~1.5-fold increase in hepatic accumulation compared with the unmodified formulation (p≤0.05). Moreover, the modified formulations had an improved antifibrotic effect compared with both unmodified LNCs and TSIIA suspension, as evidenced by the results of biochemical and histopathological evaluation.

Conclusion

The modified TSIIA-LNCs could be regarded as promising novel targeted nanomedicines for effective management of liver fibrosis.

Tanshinone IIA alters the transforming growth factor-1/Smads pathway in angiotensin II-treated rat hepatic stellate cells

Objective

To investigate the effects of tanshinone IIA on the transforming growth factor-β1 (TGF-β1)/Smads signaling pathway in angiotensin II-treated hepatic stellate cells (HSCs).

Methods

HSCs were cultured and treated with angiotensin II (10 μM) or angiotensin II (10 μM) plus tanshinone IIA (3, 10, or 30 μM). Cells were incubated for 48 hours and proliferation was determined with the Cell Counting Kit-8. The relative mRNA expression of TGF-β1, Smad4, and Smad7 was measured by quantitative real-time PCR, and the relative protein expression levels were investigated by western blotting.

Results

After angiotensin II treatment, cell proliferation was significantly accelerated. Furthermore, both the mRNA and protein expression of TGF-β1 and Smad4 was significantly up-regulated, while the mRNA and protein expression of Smad7 was significantly down-regulated compared with the control cells. Tanshinone IIA inhibited the observed effects of angiotensin II in a concentration-dependent manner, with significant inhibition exerted by tanshinone IIA at 10 and 30 μM.

Conclusions

Angiotensin II promotes the proliferation of HSCs, possibly by regulating the expression of components along the TGF-β1/Smads signaling pathway. Tanshinone IIA inhibits the angiotensin II-induced activation of this pathway, and may, therefore, have preventive and therapeutic effects in liver fibrosis.

Hepatoprotective Effect of Jianpi Huoxue Formula on Nonalcoholic Fatty Liver Disease Induced by Methionine-Choline-Deficient Diet in Rat

In parallel with the prevalence metabolic syndrome, nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease in most countries. It features a constellation of simple steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and even hepatocellular carcinoma. There are no approved drugs for effective management of NAFLD and NASH. Jianpi Huoxue formula (JPHX) mainly consists of Atractylodes macrocephal (Baizhu), Salvia miltiorrhiza (Danshen), Rasux Paeonia Alba (Baishao), Rhizoma Alismatis (Zexie), and Fructus Schisandrae Chinensis (Wuweizi), which may have beneficial effects on NAFLD. The aim of the study was to identify the effect of JPHX on NAFLD. A NAFLD model was induced by methionine-choline-deficient food (MCD) in Wistar rats and orally administered with simultaneous JPHX, once a day for 8 weeks. Hepatocellular injury, lipid profile, inflammation, fibrosis, and apoptosis were evaluated. The results showed that JPHX significantly decreased the abnormal serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels compared with the MCD model (P<0.05). Furthermore, JPHX protected MCD diet-fed rats from accumulation of hepatic triglycerides (TG) and total cholesterol (TC). Histological examination demonstrated that JPHX noticeably normalized the NAFLD activity score (NAS). Moreover, JPHX ameliorated liver inflammation by decreasing TNF-α levels and reduced collagen and matrix metalloproteinases in MCD diet-fed rats. In addition, JPHX prevented rats from MCD-induced cellular apoptosis, as suggested by TUNEL staining, and suppressed the activation of caspase 3 and 7 proteins. JPHX also inhibited the phosphorylation of JNK. In conclusion, JPHX exhibited a hepatoprotective effect against NAFLD in an MCD experimental model.

Tanshinone IIA attenuates nerve transection injury associated with nerve regeneration promotion in rats

Tanshinone IIA (Tan IIA) is the major pharmacological constituent of Salvia miltiorrhiza Bunge (Danshen) for the therapeutic purpose of preventing ischemic injury and treating cerebrovascular disease. The aim of the present study was to explore the potential neuroprotective effects of Tan IIA in sciatic nerve transection injury. We investigated the possible beneficial effects of Tan IIA in promoting nerve regeneration after nerve transection injury in rats. Nerve transection injury was induced in male Sprague-Dawley rats by left sciatic nerve transection. After neuroanastomosis, the rats were intraperitoneally (IP) injected with 6mg/kg, 15mg/kg, or 40mg/kg Tan IIA once daily for 12 weeks; the vehicle and positive control groups were injected with normal saline and mecobalamin (MeCbl, 100μg/kg), respectively. Axonal regeneration and functional recovery were evaluated by a range of morphological and functional measures 12 weeks after neuroanastomosis. The administration of 15mg/kg and 40mg/kg Tan IIA and MeCbl achieved better axonal regeneration with significant restoration of motor function as well as a marked decrease in Fluoro-Gold (FG)-labeled neurons and increased nerve regeneration. At 12 weeks post-surgery, 40mg/kg Tan IIA showed a better neuroprotective effect than 15mg/kg Tan IIA and MeCbl. There were no statistical differences between the 15mg/kg Tan IIA and MeCbl groups or the control and 6mg/kg Tan IIA groups. Our findings demonstrate that Tan IIA can alleviate nerve injury and promote nerve regeneration in a sciatic nerve transection model in rats, providing supportive evidence for Tan IIA as an effective potential therapeutic remedy for peripheral nerve injury.

Lipopolysaccharides induce Smad2 phosphorylation through PI3K/Akt and MAPK cascades in HSC-T6 hepatic stellate cells

AIMS

Endotoxemia and its pro-fibrogenic signaling play a significant role in the development of hepatic fibrosis. This study investigated whether lipopolysaccharide (LPS) directly activate cultured HSC-T6 hepatic stellate cells (HSCs) through triggering Smad-dependent pro-fibrogenic signaling pathway.

MAIN METHODS

Direct cell counting and assays for cell proliferation and migration were used to measure the effects of LPS on HSC behaviors. Quantitative PCR, Western blot, and gelatin zymography were used to quantify the molecular effects of LPS on expression of HSC activation markers and signaling activity.

KEY FINDINGS

Long-term exposure to LPS exhibited moderately stimulatory effect on HSC cell growth. A wound-healing cell migration assay showed that LPS suppressed HSC-T6 cell migration. qPCR and Western blotting detection indicated that LPS treatment induced upregulation of type I and IV collagens, α-smooth muscle actin (α-SMA), and matrix metalloproteinase-9 (MMP-9). Gelatin zymography confirmed that LPS elevated MMP-9, but not MMP-2 gelatinolytic activity. Moreover, LPS immediately stimulated Akt, EKR1/2, JNK, p38 MAPK, and Smad2 hyperphosphorylation, supporting that LPS directly triggers pro-fibrogenic Smad signaling cascade without TGF-β1 stimulation. Kinase blockade experiments demonstrated the involvement of PI3K/Akt, JNK, p38 MAPK, but not ERK1/2 signaling activation in the LPS-elicited Smad2 phosphorylation as well as the overexpression of type I collagen and α-SMA in HSC-T6 cells.

SIGNIFICANCE

These findings demonstrate that LPS exerts pro-fibrogenic effect through activation and transformation of HSCs. The tissue-remodeling effect of LPS may be attributable to its ability to activate non-canonical Smad pathway through PI3K/Akt and MAPK signaling cascades.

MicroRNA-146a-5p Negatively Regulates Pro-Inflammatory Cytokine Secretion and Cell Activation in Lipopolysaccharide Stimulated Human Hepatic Stellate Cells through Inhibition of Toll-Like Receptor 4 Signaling Pathways

Lipopolysaccharide (LPS)/toll-like receptor 4 (TLR4) signaling pathway is demonstrated to be involved in the hepatic fibrosis. MicroRNA (miR)-146a-5p is a key regulator of the innate immune response. The functional significance of miR-146a-5p during the LPS/TLR4 mediated hepatic fibrosis process remains unclear. In this study, we found that TLR4 and α-smooth muscle actin (α-SMA) were up-regulated and miR-146a-5p was down-regulated in human hepatic stellate cell (HSC) line LX2 after LPS stimulation. Overexpression of miR-146a-5p inhibited LPS induced pro-inflammatory cytokines secretion through down-regulating the expression levels of TLR-4, IL-1 receptor-associated kinase 1 (IRAK1), TNF receptor associated factor-6 (TRAF6) and phosphorylation of nuclear factor-kappa B (NF-κB). Knockdown of IRAK1 and TRAF6 also suppressed pro-inflammatory cytokine production by inhibiting NF-κB phosphorylation. In addition, miR-146a-5p mimic blocked LPS induced TRAF6 dependent c-Jun N-terminal kinase (JNK) and Smad2 activation as well as α-SMA production. Taken together, these results suggest that miR-146a-5p suppresses pro-inflammatory cytokine secretion and cell activation of HSC through inhibition of TLR4/NF-κB and TLR4/TRAF6/JNK pathway.

Experimental models of liver fibrosis

Hepatic fibrosis is a wound healing response to insults and as such affects the entire world population. In industrialized countries, the main causes of liver fibrosis include alcohol abuse, chronic hepatitis virus infection and non-alcoholic steatohepatitis. A central event in liver fibrosis is the activation of hepatic stellate cells, which is triggered by a plethora of signaling pathways. Liver fibrosis can progress into more severe stages, known as cirrhosis, when liver acini are substituted by nodules, and further to hepatocellular carcinoma. Considerable efforts are currently devoted to liver fibrosis research, not only with the goal of further elucidating the molecular mechanisms that drive this disease, but equally in view of establishing effective diagnostic and therapeutic strategies. The present paper provides a state-of-the-art overview of in vivo and in vitro models used in the field of experimental liver fibrosis research.

Tanshinone IIA Attenuates Renal Fibrosis after Acute Kidney Injury in a Mouse Model through Inhibition of Fibrocytes Recruitment

Acute kidney injury (AKI) is associated with an increased risk of developing advanced chronic kidney disease (CKD). Yet, effective interventions to prevent this conversion are unavailable for clinical practice. In this study, we examined the beneficial effects of Tanshinone IIA on renal fibrosis in a mouse model of folic acid induced AKI. We found that Tanshinone IIA treatment significantly attenuated the folic acid elicited kidney dysfunction on days 3, 14, and 28. This effect was concomitant with a much lessened accumulation of fibronectin and collagen in tubulointerstitium 28 days after folic acid injury, denoting an ameliorated renal fibrosis. The kidney protective and antifibrotic effect of Tanshinone IIA was likely attributable to an early inhibition of renal recruitment of fibrocytes positive for both CD45 and collagen I. Mechanistically, Tanshinone IIA treatment not only markedly diminished renal expression of chemoattractants for fibrocytes such as TGFβ1 and MCP-1, but also significantly reduced circulating fibrocytes at the acute phase of kidney injury. These data suggested that Tanshinone IIA might be a novel therapy for preventing progression of CKD after AKI.

Tanshinone IIA ameliorates dextran sulfate sodium-induced inflammatory bowel disease via the pregnane X receptor

Tanshinone IIA (Tan IIA) (C₁₉H₁₈O₃) is one of the major active lipophilic components in a conventional Chinese medicine called danshen, and it has long been used in the People’s Republic of China and other neighboring countries to treat patients suffering from inflammatory bowel disease (IBD). Previous experiments by many teams determined which mechanism of Tan IIA is relevant to the treatment of IBD associated with inflammation and the pregnane X receptor (PXR). The current study demonstrated that Tan IIA is an efficacious PXR agonist and its ability to induce CYP3A4 mRNA and protein expression was mediated by the transactivation of PXR, a known target of abrogating inflammation in IBD. Clinical symptoms in mice and histological assessment data suggested that administration of Tan IIA in mice demonstrated significant protection and showed that in DSS-induced IBD it acts in a concentration-dependent manner. PXR-silenced mice treated with Tan IIA demonstrated low protection against DSS-induced mouse IBD and exacerbated the severity of IBD compared with wild-type mice; PXR-silenced mice demonstrated the necessity for PXR in Tan IIA-mediated upregulation of xenobiotic metabolism genes. The IBD treatment effects of Tan IIA are partially due to PXR-mediated upregulation of xenobiotic metabolism and downregulation of inflammatory mediators. The novel findings reported here may contribute to the effective utilization of Tan IIA and its derivatives as a PXR ligand in the treatment of human IBD. This suggests that Tan IIA may have considerable clinical utility.

Overexpression of pim-3 and protective role in lipopolysaccharide-stimulated hepatic stellate cells

AIM: To investigate pim-3 expression in hepatic stellate cells (HSCs) stimulated by lipopolysaccharide (LPS), and its protective effect on HSCs.

METHODS: Rat HSC-T6 cells were stimulated by LPS. The effect of LPS on proliferation and apoptosis of HSC-T6 cells was investigated by methyl thiazoyltetrazolium (MTT) assay and flow cytometry after annexin V-fluorescein isothiocyanate/propidium iodide double staining. pim-3 mRNA and protein were detected by reverse transcriptase polymerase chain reaction and Western blotting at 48 h when HSC-T6 cells were stimulated with 1 μg/mL LPS for 0, 3, 6, 12, 24 and 48 h. The cells without stimulation served as controls. To study the effect of pim-3 kinase on HSC-T6 cells, si-pim3 (siRNA against pim-3) was transfected into HSC-T6 cells. HSC-T6 cells were subjected to different treatments, including LPS, si-pim3, or si-pim3 plus LPS, and control cells were untreated. Protein expression of pim-3 was detected at 48 h after treatment, and cell proliferation at 24 and 48 h by MTT assay. Apoptosis was detected by flow cytometry, and confirmed with caspase-3 activity assay.

RESULTS: LPS promoted HSC-T6 cell proliferation and protected against apoptosis. Significantly delayed upregulation of pim-3 expression induced by LPS occurred at 24 and 48 h for mRNA expression (pim-3/β-actin RNA, 24 or 48 h vs 0 h, 0.81 ± 0.20 or 0.78 ± 0.21 vs 0.42 ± 0.13, P < 0.05), and occurred at 12 h and peaked at 24 and 48 h for protein expression (pim-3/GAPDH protein, 12, or 24 or 48 h vs 0 h, 0.68 ± 0.12, 1.47 ± 0.25 or 1.51 ± 0.23 vs 0.34 ± 0.04, P < 0.01). pim-3 protein was ablated by si-pim3 and upregulated by LPS in HSC-T6 cells at 48 h after treatment (pim-3/GAPDH: si-pim3, si-pim3 plus LPS or LPS vs control, 0.11 ± 0.05, 0.12 ± 0.05 or 1.08 ± 0.02 vs 0.39 ± 0.03, P < 0.01). Ablation of pim-3 by si-pim3 in HSC-T6 cells partly abolished proliferation (OD at 24 h, si-pim3 group or si-pim3 plus LPS vs control, 0.2987 ± 0.050 or 0.4063 ± 0.051 vs 0.5267 ± 0.030, P < 0.01; at 48 h 0.4634 ± 0.056 or 0.5433 ± 0.031 vs 0.8435 ± 0.028, P < 0.01; si-pim3 group vs si-pim3 plus LPS, P < 0.01 at 24 h and P < 0.05 at 48 h), and overexpression of pim-3 in the LPS group increased cell proliferation (OD: LPS vs control, at 24 h, 0.7435 ± 0.028 vs 0.5267 ± 0.030, P < 0.01; at 48 h, 1.2136 ± 0.048 vs 0.8435 ± 0.028, P < 0.01). Ablation of pim3 with si-pim3 in HSC-T6 cells aggravated apoptosis (si-pim3 or si-pim3 plus LPS vs control, 42.3% ±1.1% or 40.6% ± 1.3% vs 16.8% ± 3.3%, P < 0.01; si-pim3 vs si-pim3 plus LPS, P > 0.05), and overexpression of pim-3 in the LPS group attenuated apoptosis (LPS vs control, 7.32% ± 2.1% vs 16.8% ± 3.3%, P < 0.05). These results were confirmed by caspase-3 activity assay.

CONCLUSION: Overexpression of pim-3 plays a protective role in LPS-stimulated HSC-T6 cells.

Osthole ameliorates hepatic fibrosis and inhibits hepatic stellate cell activation

Background

Hepatic fibrosis is a dynamic process which ultimately leads to cirrhosis in almost patients with chronic hepatic injury. However, progressive fibrosis is a reversible scarring response. Activation of hepatic stellate cells (HSCs) is the prevailing process during hepatic fibrosis. Osthole is an active component majorly contained in the fruit of Cnidium monnieri (L.) Cusson. This present study investigated the therapeutic effects of osthole on rat liver fibrosis and HSC activation.

Results

We established the thioacetamide (TAA)-model of Sprague–Dawley (SD) rats to induce hepatic fibrosis. Rats were divided into three groups: control, TAA, and TAA + osthole (10 mg/kg). In vivo, osthole significantly reduced liver injury by diminishing levels of plasma AST and ALT, improving histological architecture, decreasing collagen and α-SMA accumulation, and improving hepatic fibrosis scores. Additionally, osthole reduced the expression of fibrosis-related genes significantly. Osthole also suppressed the production of fibrosis-related cytokines and chemokines. Moreover, nuclear translocation of p65 was significantly suppressed in osthole-treated liver. Osthole also ameliorated TAA-induced injury through reducing cellular oxidation. Osthole showed inhibitory effects in inflammation-related genes and chemokines production as well. In vitro, we assessed osthole effects in activated HSCs (HSC-T6 and LX-2). Osthole attenuated TGF-β1-induced migration and invasion in HSCs. Furthermore, osthole decreased TNF-α-triggered NF-κB activities significantly. Besides, osthole alleviated TGF-β1- or ET-1-induced HSCs contractility.

Conclusions

Our study demonstrated that osthole improved TAA-caused liver injury, fibrogenesis and inflammation in rats. In addition, osthole suppressed HSCs activation in vitro significantly.

Electronic supplementary material

The online version of this article (doi:10.1186/s12929-015-0168-5) contains supplementary material, which is available to authorized users.

Effects of Tanshinone IIA on osteogenic differentiation of mouse bone marrow mesenchymal stem cells

Tanshinone IIA (TSA) is a lipophilic diterpene purified from the Chinese herb Danshen, which exhibits potent antioxidant and anti-inflammatory properties. Effect of TSA remains largely uninvestigated on the osteogenic differentiation of bone marrow mesenchymal stem cells (BM-MSCs), which are widely used in cell-based therapy of bone diseases. In the present study, both ALP activity at day 7 and calcium content at day 24 were upregulated during the osteogenesis of mouse BM-MSCs treated with TSA (1 and 5 μM), demonstrating that it promoted the osteogenesis at both early and late stages. We found that TSA promoted osteogenesis and inhibited osteoclastogenesis, evident by RT-PCR analysis of osteogenic marker gene expressions. However, osteogenesis was inhibited by TSA at 20 μM. We further revealed that TSA (1 and 5 μM) upregulated BMP and Wnt signaling. Co-treatment with Wnt inhibitor DKK-1 or BMP inhibitor noggin significantly decreased the TSA-promoted osteogenesis, indicating that upregulation of BMP and Wnt signaling plays a significant role and contributes to the TSA-promoted osteogenesis. Of clinical interest, our study suggests TSA as a promising therapeutic strategy during implantation of BM-MSCs for a more effective treatment of bone diseases.

Deficiency of NOX1 or NOX4 Prevents Liver Inflammation and Fibrosis in Mice through Inhibition of Hepatic Stellate Cell Activation

Reactive oxygen species (ROS) produced by nicotinamide adenine dinucleotide phosphate oxidase (NOX) play a key role in liver injury and fibrosis. Previous studies demonstrated that GKT137831, a dual NOX1/4 inhibitor, attenuated liver fibrosis in mice as well as pro-fibrotic genes in hepatic stellate cells (HSCs) as well as hepatocyte apoptosis. The effect of NOX1 and NOX4 deficiency in liver fibrosis is unclear, and has never been directly compared. HSCs are the primary myofibroblasts in the pathogenesis of liver fibrosis. Therefore, we aimed to determine the role of NOX1 and NOX4 in liver fibrosis, and investigated whether NOX1 and NOX4 signaling mediates liver fibrosis by regulating HSC activation. Mice were treated with carbon tetrachloride (CCl₄) to induce liver fibrosis. Deficiency of either NOX1 or NOX4 attenuates liver injury, inflammation, and fibrosis after CCl₄ compared to wild-type mice. NOX1 or NOX4 deficiency reduced lipid peroxidation and ROS production in mice with liver fibrosis. NOX1 and NOX4 deficiency are approximately equally effective in preventing liver injury in the mice. The NOX1/4 dual inhibitor GKT137831 suppressed ROS production as well as inflammatory and proliferative genes induced by lipopolysaccharide (LPS), platelet-derived growth factor (PDGF), or sonic hedgehog (Shh) in primary mouse HSCs. Furthermore, the mRNAs of proliferative and pro-fibrotic genes were downregulated in NOX1 and NOX4 knock-out activated HSCs (cultured on plastic for 5 days). Finally, NOX1 and NOX4 protein levels were increased in human livers with cirrhosis compared with normal controls. Thus, NOX1 and NOX4 signaling mediates the pathogenesis of liver fibrosis, including the direct activation of HSC.

Tanshinone IIA Rescued the Impairments of Primary Hippocampal Neurons Induced by BV2 Microglial Over-Activation

Activated microglia plays an important role in monitoring the microenvironment and prune neural process in healthy neural tissue, in order to maintain synaptic homeostasis. However, hyperactive microglia may release various cytotoxic factors and induce neuroinflammation, which cause neuronal damages leading to neurodegenerative diseases. Tanshinone IIA (TSA), an extract from traditional Chinese medicine, features potent anti-apoptotic and anti-inflammatory effects both in vitro and in vivo. But little is known on the effects of TSA on microglial-over-activation-induced neural impairments. In this study, by employing murine BV2 cell lines as well as the combinations of ELISA assay, immunostaining, western blotting analysis and RT-PCR, we found that TSA has the potential to exhibit anti-inflammatory effects. We hereby demonstrated that TSA rescued neural growth and development in the primary cultured hippocampal neurons from impairments caused by BV2 microglial over-activation insult. The results show that TSA attenuated the BV2 cell activation by lipopolysaccharide (LPS) stimulation through suppressing the NF-кB signal pathway. Also, conditioned mediums (CM) from TSA treated and activated BV2 cells protected against LPS-CM-induced neuronal death. Furthermore, TSA treatment could recover the inhibitory effects of LPS-CM on growth cone extension, neurite sprouting and outgrowth, as well as spinogenesis. Our findings support that TSA is capable of inhibiting BV2 cell over-activation thus has potential protective effects in the cultured hippocampal neurons. This study may lay a foundation for using TSA to restore cerebral injuries after severe neuroinflammation.

Inhibition of the spinal astrocytic JNK/MCP-1 pathway activation correlates with the analgesic effects of tanshinone IIA sulfonate in neuropathic pain

Background

Neuropathic pain (NP) continues to be challenging to treat due to lack of effective drugs. Accumulating evidence elucidated that glia-mediated inflammatory reactions play a pivotal role in the introduction and development of NP. Besides, activation of the c-Jun N-terminal kinase (JNK)/monocyte chemoattractant protein-1 (MCP-1) pathway in astrocytes has been reported to be critical for spinal astrocytic activation and neuropathic pain development after spinal nerve ligation (SNL). Tanshinone IIA, a major active component of a traditional Chinese drug, Danshen, possesses potent immuno-suppressive activities. The present study was undertaken to assess whether intraperitoneal administration of tanshinone IIA sulfonate (TIIAS) has analgesic effect on SNL-induced neuropathic pain and whether the inhibition of astrocytic activation and JNK/MCP-1 pathway is involved in the analgesic effect of TIIAS.

Methods

The effects of TIIAS on SNL-induced mechanical allodynia were assessed by behavioral testing. Immunofluorescence histochemical staining was used to detect changes of spinal astrocytes and spinal pJNK expression and localization. Immunofluorescence histochemistry and Western blot analysis were used to quantify the SNL-induced spinal pJNK expression after TIIAS administration. Enzyme-linked immunosorbent assay (ELISA) was used to detect the SNL-induced spinal expression of pro-inflammatory cytokines and MCP-1.

Results

Our results indicated that intraperitoneal TIIAS up-regulated the mechanical paw withdrawal threshold (PWT) of NP, while astrocytic activation was suppressed and accompanied by the down-regulation of IL-1β and TNF-α expression, as well as JNK phosphorylation in the spinal dorsal horn. Additionally, the release of MCP-1 was dose dependently decreased. After co-treatment with TIIAS and JNK inhibitor (SP600125), no significant increases in mechanical PWT and MCP-1 expression were observed compared with the TIIAS-treated group.

Conclusions

The present results suggest that the analgesic effects of TIIAS in neuropathic pain are mainly mediated by the down-regulation of SNL-induced astrocytic activation, which is via the inhibition of JNK/MCP-1 pathway.