Antifibrotic effects of magnesium lithospermate B on hepatic stellate cells and thioacetamide-induced cirrhotic rats

Magnesium lithospermate B enhances the potential of human-induced pluripotent stem cell-derived cardiomyocytes for myocardial repair

BACKGROUND

We previously reported that activation of the cell cycle in human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) enhances their remuscularization capacity after human cardiac muscle patch transplantation in infarcted mouse hearts. Herein, we sought to identify the effect of magnesium lithospermate B (MLB) on hiPSC-CMs during myocardial repair using a myocardial infarction (MI) mouse model.

METHODS

In C57BL/6 mice, MI was surgically induced by ligating the left anterior descending coronary artery. The mice were randomly divided into five groups (n = 10 per group); a MI group (treated with phosphate-buffered saline only), a hiPSC-CMs group, a MLB group, a hiPSC-CMs + MLB group, and a Sham operation group. Cardiac function and MLB therapeutic efficacy were evaluated by echocardiography and histochemical staining 4 weeks after surgery. To identify the associated mechanism, nuclear factor (NF)-κB p65 and intercellular cell adhesion molecule-1 (ICAM1) signals, cell adhesion ability, generation of reactive oxygen species, and rates of apoptosis were detected in human umbilical vein endothelial cells (HUVECs) and hiPSC-CMs.

RESULTS

After 4 weeks of transplantation, the number of cells that engrafted in the hiPSC-CMs + MLB group was about five times higher than those in the hiPSC-CMs group. Additionally, MLB treatment significantly reduced tohoku hospital pediatrics-1 (THP-1) cell adhesion, ICAM1 expression, NF-κB nuclear translocation, reactive oxygen species production, NF-κB p65 phosphorylation, and cell apoptosis in HUVECs cultured under hypoxia. Similarly, treatment with MLB significantly inhibited the apoptosis of hiPSC-CMs via enhancing signal transducer and activator of transcription 3 (STAT3) phosphorylation and B-cell lymphoma-2 (BCL2) expression, promoting STAT3 nuclear translocation, and downregulating BCL2-Associated X, dual specificity phosphatase 2 (DUSP2), and cleaved-caspase-3 expression under hypoxia. Furthermore, MLB significantly suppressed the production of malondialdehyde and lactate dehydrogenase and the reduction in glutathione content induced by hypoxia in both HUVECs and hiPSC-CMs in vitro.

CONCLUSIONS

MLB significantly enhanced the potential of hiPSC-CMs in repairing injured myocardium by improving endothelial cell function via the NF-κB/ICAM1 pathway and inhibiting hiPSC-CMs apoptosis via the DUSP2/STAT3 pathway.

Severity of Hepatocyte Damage and Prognosis in Cirrhotic Patients Correlate with Hepatocyte Magnesium Depletion

We aimed to evaluate the magnesium content in human cirrhotic liver and its correlation with serum AST levels, expression of hepatocellular injury, and MELDNa prognostic score. In liver biopsies obtained at liver transplantation, we measured the magnesium content in liver tissue in 27 cirrhotic patients (CIRs) and 16 deceased donors with healthy liver (CTRLs) by atomic absorption spectrometry and within hepatocytes of 15 CIRs using synchrotron-based X-ray fluorescence microscopy. In 31 CIRs and 10 CTRLs, we evaluated the immunohistochemical expression in hepatocytes of the transient receptor potential melastatin 7 (TRPM7), a magnesium influx chanzyme also involved in inflammation. CIRs showed a lower hepatic magnesium content (117.2 (IQR 110.5-132.9) vs. 162.8 (IQR 155.9-169.8) μg/g; p < 0.001) and a higher percentage of TRPM7 positive hepatocytes (53.0 (IQR 36.8-62.0) vs. 20.7 (10.7-32.8)%; p < 0.001) than CTRLs. In CIRs, MELDNa and serum AST at transplant correlated: (a) inversely with the magnesium content both in liver tissue and hepatocytes; and (b) directly with the percentage of hepatocytes stained intensely for TRPM7. The latter also directly correlated with the worsening of MELDNa at transplant compared to waitlisting. Magnesium depletion and overexpression of its influx chanzyme TRPM7 in hepatocytes are associated with severity of hepatocyte injury and prognosis in cirrhosis. These data represent the pathophysiological basis for a possible beneficial effect of magnesium supplementation in cirrhotic patients.

Natural Compounds as Source of Aldose Reductase (AR) Inhibitors for the Treatment of Diabetic Complications: A Mini Review

BACKGROUND

Aldol reductase (AR) is the polyol pathway's main enzyme that portrays a crucial part in developing 'complications of diabetes' involving cataract, retinopathy, nephropathy, and neuropathy. These diabetic abnormalities are triggered tremendously via aggregation of sorbitol formation (catalyzed by AR) in the polyol pathway. Consequently, it represents an admirable therapeutic target and vast research was done for the discovery of novel molecules as potential AR inhibitors for diabetic complications.

OBJECTIVE

This review article has been planned to discuss an outline of diabetic complications, AR and its role in diabetic complications, natural compounds reported as AR inhibitors, and benefits of natural/plant derived AR inhibitors for the management of diabetic abnormalities.

RESULTS

The goal of AR inhibition remedy is to stabilize the increased flux of blood glucose and sorbitol via the 'polyol pathway' in the affected tissues. A variety of synthetic inhibitors of AR have been established such as tolrestat and sorbinil, but both of these face limitations including low permeability and health problems. Pharmaceutical industries and other scientists were also undertaking work to develop newer, active, and 'safe' AR inhibitors from natural sources. Therefore, several naturally found molecules were documented to possess a potent inhibitory action on AR activity.

CONCLUSION

Natural inhibitors of AR appeared as harmless pharmacological agents for controlling diabetic complications. The detailed literature throughout this article shows the significance of herbal extracts and phytochemicals as prospective useful AR inhibitors in treating diabetic complications.

Protective rules of natural antioxidants against gamma-induced damage-A review

Phytochemicals accessible in food have demonstrated efficiency against impairment by gamma radiation. The review presented here is an attempt to show the pharmacological outline of the activity of the natural antioxidants and its primary action of molecular mechanism against the damage induced by gamma rays. This research focused on the results of the in vitro dosage of natural antioxidants relationship, and on the correlation of this information with the statistical variables. Moreover, it deliberated the natural compounds which could decrease the unwelcome impacts of gamma radiation and safeguard biological systems from radiation-stimulated genotoxicity. The outcomes indicated that natural compounds can be utilized as an adjunct to orthodox radiotherapy and cultivate it as an effectual drug for the clinical administration of ailments.

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

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

Magnesium, Little Known But Possibly Relevant: A Link between NASH and Related Comorbidities

Non-alcoholic steatohepatitis (NASH) is characterized by an abnormal hepatic lipid accumulation accompanied by a necro-inflammatory process and a fibrotic response. It comprises from 10% to 30% of cases of patients with non-alcoholic liver disease, which is a global health problem affecting around a quarter of the worldwide population. Nevertheless, the development of NASH is often surrounded by a pathological context with other comorbidities, such as cardiovascular diseases, obesity, insulin resistance or type 2 diabetes mellitus. Dietary imbalances are increasingly recognized as the root cause of these NASH-related comorbidities. In this context, a growing concern exists about whether magnesium consumption in the general population is sufficient. Hypomagnesemia is a hallmark of the aforementioned NASH comorbidities, and deficiencies in magnesium are also widely related to the triggering of complications that aggravate NASH or derived pathologies. Moreover, the supplementation of this cation has proved to reduce mortality from hepatic complications. In the present review, the role of magnesium in NASH and related comorbidities has been characterized, unraveling the relevance of maintaining the homeostasis of this cation for the correct functioning of the organism.

Decellularized hepatic extracellular matrix hydrogel attenuates hepatic stellate cell activation and liver fibrosis

Liver fibrosis results from excessive accumulation of extracellular matrix (ECM) proteins that distort the hepatic architecture. Progression of liver fibrosis results in cirrhosis and liver failure, and often, liver transplantation is required. The decellularized liver tissue contains different components that mimic the natural hepatic environment. We hypothesized that a decellularized liver hydrogel can be used to replace the necrotic hepatocytes and damaged ECM. Therefore, our aim in this study is to develop a therapy for treating liver fibrosis. Mice livers were decellularized and processed to form a hepatic hydrogel. We evaluated the biocompatibility and bioactivity of the hydrogel. The ability of the hydrogel to enhance the migration of hepatocytes and endothelial cells was investigated. Human hepatic stellate cell line (LX-2) activated by transforming growth factor-β1 (TGF-β1) was used as in vitro model for fibrogenesis. Then, the hydrogel was injected into the liver parenchyma of mice after the induction of liver fibrosis using thioacetamide. The resulting hydrogel maintained a complex composition, which included glycosaminoglycans, collagen, elastin, and growth factors. Hepatocytes and endothelial cells were shown to migrate toward the hydrogel in vitro. Liver hydrogel improved TGF-β1-induced LX-2 cells activation via blocking the TGF-β1/Smad pathway. The matrix was delivered successfully in vivo and enhanced the reduction of fibrosis and recovery to a nearly normal structure. In conclusion, we have demonstrated that the liver hydrogel can be utilized as an injectable biomaterial for liver tissue engineering in order to reduce the degree of fibrosis.

Dunaliella salina microalgae oppose thioacetamide-induced hepatic fibrosis in rats

Several hepatic pathological conditions are correlated with the stimulation of hepatic stellate cells. This induces a cascade of events producing accretion of extracellular matrix components triggering fibrosis. Dunaliella salina, rich in carotenoids, was investigated for its potential antagonizing activity; functionally and structurally against thioacetamide (TAA) - induced hepatic fibrosis in rats. Adult male albino Wistar rats were treated with three dose levels of D. salina powder or extract (daily, p.o.); for 6 weeks, concomitantly with TAA injection. Serum levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), bilirubin and albumin were determined. Reduced glutathione (GSH), malondialdehyde (MDA), smooth muscle actin alpha (α-SMA) and collagen I hepatic contents were also estimated. Treatment with D. salina powder or extract caused a significant decline in serum levels of AST, ALT, ALP, bilirubin, MDA and hepatic contents of α-SMA and collagen I. Additionally, serum albumin and GSH hepatic content were highly elevated. Liver histopathological examination also indicated that D. salina reduced fibrosis, centrilobular necrosis, and inflammatory cell infiltration evoked by TAA. The results implied that D. salina exerts protective action against TAA-induced hepatic fibrosis in rats. The phytochemical investigation revealed high total carotenoid content prominently β-carotene (15.2 % of the algal extract) as well as unsaturated fatty acids as alpha-linolenic acid which accounts for the hepatoprotective activity.

Magnesium and liver disease

Magnesium is a vital cation that takes part in many cellular processes. Magnesium balance can be disturbed in multiple conditions, and differences in magnesium concentration can be responsible for numerous physiological and pathological processes. Magnesium deficiency is commonly associated with liver diseases, and may result from low nutrient uptake, greater urinary secretion, low serum albumin concentration, or hormone inactivation. In turn, low magnesium content in serum and liver tissue can lead to the progression of these diseases, due to a disruption in mitochondrial function, defective protein kinase C (PKC) translocation, inflammatory responses, oxidative stress, or metabolic disorders. Furthermore, magnesium supplementation can improve liver function in certain liver diseases. This paper comprehensively reviews the changes in magnesium concentrations associated with liver cirrhosis, alcoholic liver disease (ALD), liver cancer, and viral hepatitis, and explains how such changes may in turn impact these disease processes.

Danshen: a phytochemical and pharmacological overview

Danshen, the dried root or rhizome of Salvia miltiorrhiza Bge., is a traditional and folk medicine in Asian countries, especially in China and Japan. In this review, we summarized the recent researches of Danshen in traditional uses and preparations, chemical constituents, pharmacological activities and side effects. A total of 201 compounds from Danshen have been reported, including lipophilic diterpenoids, water-soluble phenolic acids, and other constituents, which have showed various pharmacological activities, such as anti-inflammation, anti-oxidation, anti-tumor, anti-atherogenesis, and anti-diabetes. This article intends to provide novel insight information for further development of Danshen, which could be of great value to its improvement of utilization.

The Protective Effect of Magnesium Lithospermate B on Hepatic Ischemia/Reperfusion via Inhibiting the Jak2/Stat3 Signaling Pathway

Acute inflammation is an important component of the pathogenesis of hepatic ischemia/reperfusion injury (HIRI). Magnesium lithospermate B (MLB) has strong neuroprotective and cardioprotective effects. The purpose of this study was to determine whether MLB had underlying protective effects against hepatic I/R injury and to reveal the potential mechanisms related to the hepatoprotective effects. In this study, we first examined the protective effect of MLB on HIRI in mice that underwent 1 h ischemia followed by 6 h reperfusion. MLB pretreatment alleviated the abnormal liver function and hepatocyte damage induced by I/R injury. We found that serum inflammatory cytokines, including IL-6, IL-1β, and TNF-α, were significantly decreased by MLB during hepatic ischemia/reperfusion (I/R) injury, suggesting that MLB may alleviate hepatic I/R injury via inhibiting inflammatory signaling pathways. Second, we investigated the protein level of p-Jak2/Jak2 and p-Stat3/Stat3 using Western blotting and found that MLB could significantly inhibit the activation of the Jak2/Stat3 signaling pathway, which was further verified by AG490 in a mouse model. Finally, the effect of MLB on the Jak2/Stat3 pathway was further assessed in an in vitro model of RAW 264.7 cells; 1 µg/ml LPS induced the secretion of inflammatory mediators, including IL-6, TNF-α, and activation of the Jak2/Stat3 signaling pathway. MLB significantly inhibited the abnormal secretion of inflammatory factors and the activation of the Jak2/Stat3 signaling pathway in RAW264.7 cells. In conclusion, MLB was found for the first time to reduce inflammation induced by hepatic I/R via suppressing the Jak2/Stat3 pathway.

Salvianolic acid B, an antioxidant derived from Salvia militarize, protects mice against γ‑radiation‑induced damage through Nrf2/Bach1

Salvianolic acid B (SB) is an antioxidant derived from Salvia militarize, and is one of the most widely used herbs in traditional Chinese medicine. SB is a potent antioxidant that has been well documented as a scavenger of oxygen free radicals, and has been used for the prevention and treatment of atherosclerosis-associated disorders. To explore its potential therapeutic effects in treating radiation damage, in this study, mice were treated with SB at different doses of 5, 12.5 and 20 mg/kg, subsequent to receiving γ-irradiation. The effects of SB on peripheral blood, bone marrow nucleated cells, spleen and thymus indices, and oxidation resistance were evaluated in both radiated mice and control groups. The results indicated that SB significantly increased the counts of peripheral white blood cells, red blood cells and platelets. The number of nucleated cells in the bone marrow and the level of protein increased as well. In addition, improved spleen and thymus indices in the bone marrow were observed. SB treatment additionally reversed the deterioration of both the thymus and spleen indices, which is associated with increased serum superoxide dismutase activity and decreasing malondialdehyde levels via nuclear factor (erythroid-derived 2)-like 2 protein/BTB and CNC homology 1 mediated antioxidant effect. Furthermore, ROS levels and Bax protein expression were also suppressed by SB. The data suggested that SB is effective in protecting mice from γ-radiation injury, and could potentially be applicable for clinical use. Notably, the present study identified a promising candidate drug for enhancing the hematopoietic and immune systems.

Comparative study of antifibrotic activity of some magnesium-containing supplements on experimental liver toxicity. Molecular study

INTRODUCTION

Liver fibrosis is the excessive accumulation of extracellular matrix (ECM) proteins including collagen that occurs in most types of chronic liver diseases. This study aimed to investigate and compare the therapeutic efficacy of different magnesium (Mg)-containing supplements (formulations A, B, and C) on carbon tetrachloride (CCl₄)-induced liver fibrosis in rats.

METHODS

Liver fibrosis was induced by intraperitoneal injection of rats with CCl₄ (1:1 in olive oil, 2 mL/kg, three times/week) for 4 weeks, and then rats were orally treated with different Mg-containing supplements (formulations A, B, and C) once daily for another one month. Liver fibrosis was quantified by evaluation of expressions of Collagen I, transforming growth factor β-1 (TGFβ1), platelet-derived growth factor-C (PDGF-C), nuclear factor kappa-β (NF-κβ), and measurement of hepatic collagen (hydroxyproline) level. Also, malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH) level, superoxide dismutase (SOD), and glutathione-S-transferase (GST) activities were estimated.

RESULTS

CCl₄ administration significantly elevated expressions of the studied genes, hepatic hydroxyproline, MDA, and NO levels and caused depletion of GSH level, decreased SOD, and GST activities when compared with those of their corresponding control, p < 0.05. All magnesium supplements significantly inhibited expressions of the studied genes and attenuated the hepatic hydroxyproline level as compared with those of CCl₄-treated group_; p < 0.05; for NF-κβ, the highest inhibition was by formulations B and C. Regarding Collagen I, TGFβ1, and hepatic hydroxyproline content, the highest inhibition was by Formulation C, and Formulation A revealed highest inhibition for PDGF-C. All magnesium supplements revealed normalization of oxidant and antioxidants parameters. Histopathological examination supports the biochemical and molecular findings.

CONCLUSION

Mg supplements were effective in the treatment of hepatic CCl₄-induced fibrosis-rat model.

Preclinical Models for Investigation of Herbal Medicines in Liver Diseases: Update and Perspective

Liver disease results from a dynamic pathological process associated with cellular and genetic alterations, which may progress stepwise to liver dysfunction. Commonly, liver disease begins with hepatocyte injury, followed by persistent episodes of cellular regeneration, inflammation, and hepatocyte death that may ultimately lead to nonreversible liver failure. For centuries, herbal remedies have been used for a variety of liver diseases and recent studies have identified the active compounds that may interact with liver disease-associated targets. Further study on the herbal remedies may lead to the formulation of next generation medicines with hepatoprotective, antifibrotic, and anticancer properties. Still, the pharmacological actions of vast majority of herbal remedies remain unknown; thus, extensive preclinical studies are important. In this review, we summarize progress made over the last five years of the most commonly used preclinical models of liver diseases that are used to screen for curative herbal medicines for nonalcoholic fatty liver disease, liver fibrosis/cirrhosis, and liver. We also summarize the proposed mechanisms associated with the observed liver-protective, antifibrotic, and anticancer actions of several promising herbal medicines and discuss the challenges faced in this research field.

Salvia miltiorrhiza: Traditional medicinal uses, chemistry, and pharmacology

Salvia miltiorrhiza Bunge (SM) is a very popular medicinal plant that has been extensively applied for many years to treat various diseases, especially coronary heart diseases and cerebrovascular diseases, either alone or in combination with other Chinese plant-based medicines. Although a large number of studies on SM have been performed, they are scattered across a variety of publications. The present review is an up-to-date summary of the published scientific information about the traditional uses, chemical constituents, pharmacological effects, side effects, and drug interactions with SM, in order to lay the foundation for further investigations and better utilization of SM. SM contains diverse chemical components including diterpenoid quinones, hydrophilic phenolic acids, and essential oils. Many pharmacological studies have been done on SM during the last 30 years, focusing on the cardiovascular and cerebrovascular effects, and the antioxidative, neuroprotective, antifibrotic, anti-inflammatory, and antineoplastic activities. The research results strongly support the notion that SM has beneficial therapeutic properties and has a potential of being an effective adaptogenic remedy.

Hepatoprotective and Anti-fibrotic Agents: It's Time to Take the Next Step

Hepatic fibrosis and cirrhosis cause strong human suffering and necessitate a monetary burden worldwide. Therefore, there is an urgent need for the development of therapies. Pre-clinical animal models are indispensable in the drug discovery and development of new anti-fibrotic compounds and are immensely valuable for understanding and proofing the mode of their proposed action. In fibrosis research, inbreed mice and rats are by far the most used species for testing drug efficacy. During the last decades, several hundred or even a thousand different drugs that reproducibly evolve beneficial effects on liver health in respective disease models were identified. However, there are only a few compounds (e.g., GR-MD-02, GM-CT-01) that were translated from bench to bedside. In contrast, the large number of drugs successfully tested in animal studies is repeatedly tested over and over engender findings with similar or identical outcome. This circumstance undermines the 3R (Replacement, Refinement, Reduction) principle of Russell and Burch that was introduced to minimize the suffering of laboratory animals. This ethical framework, however, represents the basis of the new animal welfare regulations in the member states of the European Union. Consequently, the legal authorities in the different countries are halted to foreclose testing of drugs in animals that were successfully tested before. This review provides a synopsis on anti-fibrotic compounds that were tested in classical rodent models. Their mode of action, potential sources and the observed beneficial effects on liver health are discussed. This review attempts to provide a reference compilation for all those involved in the testing of drugs or in the design of new clinical trials targeting hepatic fibrosis.

Antidepressant-like effects of magnesium lithospermate B in a rat model of chronic unpredictable stress

CONTEXT

Magnesium lithospermate B (MLB), an active polyphenol acid of Danshen [Radix Salviae miltiorrhizae (Labiatae)], shows neuroprotective and anti-inflammatory effects in vivo and in vitro.

OBJECTIVE

We hypothesized that MLB might exert antidepressant-like effects by targeting the neuroinflammatory signals.

MATERIALS AND METHODS

Sprague-Dawley rats were subjected to the chronic unpredictable stress (CUS) protocol. Rats in the control group received no CUS during the whole experiment. In the model group, rats were exposed to CUS for 7 weeks. From the beginning of the 5th week, model group rats were randomly grouped and subjected to different treatments. In the experiment, control and model group rats were intraperitoneally (i.p.) injected with saline. MLB was dissolved in saline to give a final concentration, and the rats were injected (i.p.) with 15, 30, or 60 mg/kg MLB once a day for 3 weeks.

RESULTS

MLB administration significantly reduced: (1) the immobility time in the forced swimming test (19 s, p < 0.05); (2) the immobility time in the tail suspension test (76.3 s, p < 0.05); (3) the corticosterone (CORT) concentrations in the serum (21.7 nmol/L, p > 0.05); (4) the pro-inflammatory cytokine levels in the serum - TNF-α (92.1 pg/ml, p < 0.05), IL-1β (86.9 pg/ml, p < 0.05), and IL-6 (93.8 pg/ml, p < 0.05); (5) pro-inflammatory cytokine levels in tissue - TNF-α (3.2 pg/mg protein, p < 0.05), IL-1β (1.5 pg/mg protein, p > 0.05), and IL-6 (6.3 pg/mg protein, p < 0.05); and (6) phospho-NF-κB (1.6, p < 0.05) and phospho-IκB-α (0.4, p < 0.05) expression in tissue.

DISCUSSION AND CONCLUSION

The results suggested that MLB might exert therapeutic actions on depression-like behavior and the HPA axis hyperactivity in CUS rats, and the mechanisms underlying the antidepressant-like effects of MLB might be mediated by regulation of the expression of NF-κB and IκB-α in rats.

Liver fibrosis and mechanisms of the protective action of medicinal plants targeting inflammation and the immune response

Inflammation is a central feature of liver fibrosis as suggested by its role in the activation of hepatic stellate cells leading to extracellular matrix deposition. During liver injury, inflammatory cells are recruited in the injurious site through chemokines attraction. Thus, inflammation could be a target to reduce liver fibrosis. The pandemic trend of obesity, combined with the high incidence of alcohol intake and viral hepatitis infections, highlights the urgent need to find accessible antifibrotic therapies. Medicinal plants are achieving popularity as antifibrotic agents, supported by their safety, cost-effectiveness, and versatility. The aim of this review is to describe the role of inflammation and the immune response in the pathogenesis of liver fibrosis and detail the mechanisms of inhibition of both events by medicinal plants in order to reduce liver fibrosis.

Protective mechanisms of medicinal plants targeting hepatic stellate cell activation and extracellular matrix deposition in liver fibrosis

During chronic liver injury, hepatic stellate cells (HSC) are activated and proliferate, which causes excessive extracellular matrix (ECM) deposition, leading to scar formation and fibrosis. Medicinal plants are gaining popularity as antifibrotic agents, and are often safe, cost-effective, and versatile. This review aims to describe the protective role and mechanisms of medicinal plants in the inhibition of HSC activation and ECM deposition during the pathogenesis of liver fibrosis. A systematic literature review on the anti-fibrotic mechanisms of hepatoprotective plants was performed in PubMed, which yielded articles about twelve relevant plants. Many of these plants act via disruption of the transforming growth factor beta 1 signaling pathway, possibly through reduction in oxidative stress. This reduction could explain the inhibition of HSC activation and reduction in ECM deposition. Medicinal plants could be a source of anti-liver fibrosis compounds.

Combined effects of an antioxidant and caspase inhibitor on the reversal of hepatic fibrosis in rats

We sought to determine the hepatic fibrosis-reversal effects upon simultaneous administration of lithospermate B (LAB), an anti-oxidant, and nivocasan, a caspase inhibitor, to rats compared with each compound alone. Liver fibrosis was induced in Sprague-Dawley rats by thioacetamide (TAA). Rats were treated with TAA and then given LAB and (or) nivocasan. Fibrotic areas were evaluated quantitatively by computerized morphometry. Apoptosis was assessed using a TUNEL assay, and immunohistochemical staining for malondialdehyde (MDA) and 4-hydroxy-2-nonenal (4HNE) was performed to assess oxidative stress levels. Real-time quantitative PCR was used to quantify expression of fibrosis-related genes. The degree of hepatic fibrosis was significantly reduced in rats treated with LAB and nivocasan compared to either treatment alone (P < 0.001). Treatment with each compound significantly decreased expression of fibrosis-related genes, such as type I collagen α1 (col1α1), α-SMA and TGF-β1 (P < 0.05). Co-treatment with LAB and nivocasan further reduced col1α1 expression compared to treatment with either compound. A TUNEL assay revealed that hepatocyte apoptosis was significantly decreased in the group treated with nivocasan compared to other groups (P < 0.01). Immunohistochemistry showed a decrease in MDA and 4HNE, reflecting amelioration of oxidative stress, when LAB or LAB+nivocasan was administered compared to nivocasan alone (P < 0.01). Nivocasan was found to inhibit caspase-1, -3, -7, -9 and gliotoxin-induced death of rat-derived hepatic stellate cells was inhibited by nivocasan administration without overexpression of α-SMA.

CONCLUSIONS

Co-incidental administration of LAB and nivocasan suppressed oxidative stress and apoptosis, resulting in enhanced reversal of hepatic fibrosis in rat.

Effects of oral intake of hydrogen water on liver fibrogenesis in mice

AIM

Liver fibrosis is the universal consequence of chronic liver diseases. Sustained hepatocyte injury initiates an inflammatory response, thereby activating hepatic stellate cells, the principal fibrogenic cells in the liver. Reactive oxygen species are involved in liver injury and are a promising target for treating liver fibrosis. Hydrogen water is reported to have potential as a therapeutic tool for reactive oxygen species-associated disorders. This study aimed to investigate the effects of hydrogen water on liver fibrogenesis and the mechanisms underlying these effects.

METHODS

C57BL/6 mice were fed with hydrogen water or control water, and subjected to carbon tetrachloride, thioacetamide and bile duct ligation treatments to induce liver fibrosis. Hepatocytes and hepatic stellate cells were isolated from mice and cultured with or without hydrogen to test the effects of hydrogen on reactive oxygen species-induced hepatocyte injuries or hepatic stellate cell activation.

RESULTS

Oral intake of hydrogen water significantly suppressed liver fibrogenesis in the carbon tetrachloride and thioacetamide models, but these effects were not seen in the bile duct ligation model. Treatment of isolated hepatocyte with 1 μg/mL antimycin A generated hydroxyl radicals. Culturing in the hydrogen-rich medium selectively suppressed the generation of hydroxyl radicals in hepatocytes and significantly suppressed hepatocyte death induced by antimycin A; however, it did not suppress hepatic stellate cell activation.

CONCLUSION

We conclude that hydrogen water protects hepatocytes from injury by scavenging hydroxyl radicals and thereby suppresses liver fibrogenesis in mice.

Magnesium lithospermate B improves myocardial function and prevents simulated ischemia/reperfusion injury-induced H9c2 cardiomyocytes apoptosis through Akt-dependent pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Magnesium lithospermate B (MLB), an active polyphenol acid of Radix Salviae Miltiorrhizae (Danshen), showed a wide range of pharmacological activities in cardiovascular diseases. However, its role in protection against ischemia/reperfusion injury in H9c2 cardiomyocytes has not been elucidated. This study was aimed to investigate the protective effect and potential molecular mechanisms of MLB on apoptosis in H9c2 cardiomyocytes in vitro.

MATERIALS AND METHODS

We tested cell viability, shortening amplitude, necrosis, apoptosis, and the expression levels of Akt, phosphorylated Akt, Bcl-2 and Bax after 2-h simulated ischemia and 24-h simulated reperfusion in H9c2 cardiomyocytes. We further observed the contractile function in hearts after they were subjected to global 30-min ischemia and 180-min reperfusion.

RESULTS

Pretreatment with MLB markedly increased cell viability and while reducing evidence of necrosis and apoptosis in H9c2 cardiomyocytes. In addition, the expression of Bcl-2 and Bax protein was modulated. The results also showed that MLB significantly increased phosphorylation of Akt and that this phosphorylation can be partially inhibited by phosphoinositide 3-kinase/Akt inhibitor. Furthermore, MLB improved MI/R-induced myocardial contractile function.

CONCLUSION

Our results showed that MLB prevents I/R-induced myocardial damage by reducing necrosis and apoptosis in H9c2 cardiomyocytes and improving myocardial function in rat hearts.

Magnesium lithospermate B reduces myocardial ischemia/reperfusion injury in rats via regulating the inflammation response

CONTEXT

Magnesium lithospermate B (MLB), an active polyphenol acid of Danshen [Radix Salviae miltiorrhizae (Labiatae)], showed renoprotective, neuroprotective and myocardial salvage effects. Previous studies demonstrated that MLB could effectively suppress the production of cytokines and their associated signaling pathways in activated human T cells.

OBJECTIVE

The purpose of this study was to examine the beneficial effects of MLB on myocardial ischemia/reperfusion (MI/R) injury and to explore its potential mechanisms related to anti-inflammation.

MATERIALS AND METHODS

Sprague-Dawley rats were grouped as sham group, model group and MLB-treated (15, 30 and 60 mg/kg) groups. Animals were subjected to MI/R injury by the occlusion of left anterior descending artery for 30 min followed by reperfusion for 3 h. At the end of reperfusion, blood samples were collected to determine the serum levels of cardiac troponin (cTnI), creatine kinase-MB (CK-MB), tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β) and interleukin 6 (IL-6). Hearts were harvested to assess infarct size, histopathological changes and the activity of myeloperoxidase (MPO). The expression of phosphor-IkB-α and phosphor-nuclear factor kappa B (NF-κB) were assayed by western blot.

RESULTS

MLB administration significantly (p < 0.05) reduced: (1) ST-segment elevation (0.23 mv), (2) the infarct size (22.5%), (3) histological scores of myocardial injury (1.67 score), (4) myocardial injury marker enzymes: cTnI (5.64 ng/ml) and CK-MB (49.57 ng/ml) levels, (5) pro-inflammatory cytokines: TNF-α (97.36 pg/ml), IL-1β (93.35 pg/ml) and IL-6 (96.84 pg/ml) levels, (6) MPO activity (1.82 U/mg), (7) phosphor-NF-κB (0.87) and phosphor-IkB-α (0.96) expression.

DISCUSSION AND CONCLUSION

Our study provided evidence that MLB ameliorated the inflammatory process associated with MI/R injury via NF-κB inactivation.

Real time in vivo investigation of superoxide dynamics in zebrafish liver using a single-fiber fluorescent probe

Superoxide anion is the key radical that causes intracellular oxidative stress. The lack of a method to directly monitor superoxide concentration in vivo in real time has severely hindered our understanding on its pathophysiology. We made transgenic zebrafish to specifically express yellow fluorescent proteins, a reversible superoxide-specific indicator, in the liver and used a fiber-optic fluorescent probe to noninvasively monitor the superoxide concentration in real time. Several superoxide-inducing and scavenging reagents were administrated onto the fish to alter superoxide concentrations. The distinct biochemical pathways of the reagents can be discerned from the transient behaviors of fluorescence time courses. These results demonstrate the feasibility of this method for analyzing superoxide dynamics and its potential as an in vivo pharmaceutical screening platform.

Multitargeted inhibition of hepatic fibrosis in chronic iron-overloaded mice by Salvia miltiorrhiza

ETHNOPHARMACOLOGICAL RELEVANCE

Salvia miltiorrhiza (SM, also known as Danshen) is a well-known Chinese medicinal herb, which has shown hepatoprotective effects with anti-fibrotic, anti-oxidative, anti-inflammatory and anti-apoptotic properties. To explore the effects and potential mechanism of SM against hepatic fibrosis induced by chronic iron overload in mice.

MATERIALS AND METHODS

Sixty male mice were randomized into five groups (n=12 in each group): control (saline), iron overload, iron overload with low-dose SM (3g/kg/day), iron overload with high-dose SM (6g/kg/day) and iron overload with deferoxamine (100mg/kg/day) groups. The iron overload model was established by intraperitoneal injection with iron dextran at 50mg/kg body weight/day, and the entire course lasted for 7 weeks. The major constituents of SM injection were quantified by high performance liquid chromatography. Changes of hepatic iron, hydroxyproline (Hyp), glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) were assayed by standard procedures. Protein expression levels of type I collagen, type III collagen, tumor necrosis factor-α (TNF-α) and interleukin-1α (IL-1α) were analyzed by immunohistochemistry, and mRNA levels of transforming growth factor-β (TGF-β), matrix metal proteinase-9 (MMP-9) and caspase-3 were detected by RT-PCR. Morphological changes were observed with Prussian blue, Masson's trichrome and hematoxylin-eosin staining.

RESULTS

Treatment of chronic iron-overloaded mice with SM dose-dependently ameliorated changes in hepatic morphology and coefficient, reduced iron deposition and Hyp content, suppressed overexpression of type I collagen and type III collagen, downregulated expression of TGF-β mRNA, and upregulated expression of MMP-9 mRNA in the liver. Moreover, SM treatment contributed to decreased MDA content, increased SOD activity and GSH content, while it reduced expression of TNF-α, IL-1α and caspase-3.

CONCLUSIONS

SM displayed anti-fibrotic activity in the liver induced by chronic iron overload, which may be attributed to multitargeted inhibition of iron deposition and collagen accumulation, as well as oxidative stress, inflammation and apoptosis.

Alteration of micronutrient status in compensated and decompensated liver cirrhosis

Decompensation followed by death is the most serious outcome in patients suffering from cirrhosis of the liver. Alteration of trace elements may play a vital role in the process of decompensation. To examine the change in status of trace elements during the decompensation process, we analysed the zinc, copper, iron, magnesium, bilirubin and albumin levels in the serum of compensated (n = 34) and decompensated (n = 31) liver cirrhosis patients and compared them with healthy control group (n = 36) by post hoc ANOVA. We observed significant alteration in the selected micronutrients in the diseased group relative to healthy controls (P < 0.05). Moreover, mean serum zinc and iron levels were significantly lower with a higher level of serum copper in decompensated cirrhosis group than in compensated group (P < 0.05). However, no significant decrease of serum magnesium was found between the two diseased groups. Our findings imply that the trace elements like zinc, copper and iron might exert important contributory roles in decompensation process in liver cirrhosis and hence, may be utilized as important biomarkers for these patients. Furthermore, we propose that replacements of those micronutrients at an early stage can delay or prevent the severe outcomes like hepatic encephalopathy, gastrointestinal bleeding, severe jaundice or ascites in these patients.

The cochlea magnesium content is negatively correlated with hearing loss induced by impulse noise

OBJECTIVE

Magnesium is proved to attenuate acoustic trauma, and reactive oxygen species (ROS) formation is a critical role that involves hearing loss induced by impulse noise. We aimed to investigate the relationship between the cochlea magnesium content, ROS formation and hearing loss induced by impulse noise.

METHODS

Ninety pigmented guinea pigs were exposed to impulse noise. Auditory thresholds were assessed by sound-evoked auditory brainstem response (ABR) 24h before and 72h after exposure to impulse noise. 4-Hydroxynonenal(HNE) used as a marker of ROS was determined immunohistochemically. The cochlea magnesium content was examined with the method of energy dispersive x-ray analysis, and the cochlea was also detected with scanning electron microscope. The relationship between the cochlea magnesium content, ROS formation and hearing loss was analyzed.

RESULTS

There was loss of outer hair cell cilia accompanying with significant auditory threshold shift after impulse noise exposure. ROS was positive in the organ of Corti of all animals. The cochlea magnesium content was negatively correlated with ROS formation and hearing loss.

CONCLUSIONS

Inhibiting ROS formation is one of the mechanisms for magnesium to reduce acoustic trauma, and difference in cochlea magnesium contents is one of the factors that induce varying degrees of cochlear damage among each individual after acoustic trauma.

Spectral analysis of thioacetamide-induced electroencephalographic changes in rats

Thioacetamide (TAA) is widely used as a model of hepatic encephalopathy (HE). The aim of our study was to investigate the effects of TAA on electroencephalographic (EEG) changes in rats and to compare them with human HE. Male Wistar rats were divided into groups: (1) saline-treated group and (2) TAA-treated groups: TAA300 (300 mg/kg), TAA600 (600 mg/kg), and TAA900 (900 mg/kg). Daily dose of TAA (300 mg/kg) was administered intraperitoneally once (TAA300), twice (TAA600), or thrice (TAA900) in subsequent days. EEG changes were recorded about 24 h after the last dose of TAA. Absolute and relative power density in alpha bands were significantly higher in TAA300 versus control group. In TAA300, absolute beta power density was higher and relative beta power density was lower versus control group. Absolute alpha, theta, delta, and relative theta power were significantly lower, while relative power in delta band was significantly higher in TAA900 versus control group ( p < 0.01). In conclusion, decrease in EEG voltage with an increase in delta relative power, which correspond to the EEG manifestations of severe HE in humans, was observed in TAA900 group. Electrical activity in TAA300 group correlates with mild HE in humans.

Pharmacological actions and therapeutic applications of Salvia miltiorrhiza depside salt and its active components

Salvia miltiorrhiza, a traditional medical herb known as danshen, has been widely used in China to improve blood circulation, relieve blood stasis, and treat coronary heart disease. S miltiorrhiza depside salt is a novel drug recently developed at the Shanghai Institute of Materia Medica; it contains magnesium lithospermate B (MLB) and its analogs, rosmarinic acid (RA) and lithospermic acid (LA), as active components. The drug has been used in the clinic to improve blood circulation and treat coronary heart disease. The pharmacological effects of the depside salt from S miltiorrhiza and its components have been extensively investigated. Experimental studies have demonstrated that magnesium lithospermate B possesses a variety of biological activities, especially protective effects in the cardiovascular system such as attenuation of atherosclerosis and protection against myocardial ischemia-reperfusion injury. Rosmarinic acid and lithospermic acid also show beneficial effects on the cardiovascular system. This paper reviews the recent findings regarding the mechanisms underlying the pharmacological actions of the active components of S miltiorrhiza depside salt, based on published works and our own observations.

Magnesium lithospermate B mediates anti-inflammation targeting activator protein-1 and nuclear factor-kappa B signaling pathways in human peripheral T lymphocytes

The activation of T lymphocytes contributes to the inflammatory processes of atherosclerotic diseases. Danshen is a traditional Chinese medicine and has shown therapeutic effects in patients with cardiovascular and cerebrovascular diseases. We investigated the effects of aqueous extract of Danshen (magnesium lithospermate B (MLB)) on phorbol 12-myristate acetate+ionomycin and anti-CD3+anti-CD28 monoclonal antibody-activated T cells. We showed that MLB inhibited interleukin (IL)-2, IL-4, tumor necrosis factor-alpha and interferon-gamma production from activated T cells. The expressions of T cell activation markers CD 25 and CD 69 were effectively reduced. EMSA analysis indicated that MLB down-regulated activator protein-1 (AP-1), nuclear factor kappa B (NF-κB) and octamer binding transcription factor (Oct-1) DNA-binding activity. In addition, MLB inhibited c-jun N-terminal kinase (JNK) but not extracellular signal regulated protein kinase activity. MLB also inhibited IκBα degradation, nuclear translocation of p65 and p50 as well as decreased IκBα kinase (IKK) activity. Through suppressing JNK-AP-1, IKK-IκBα-NF-κB and Oct-1 signaling pathways by MLB in activated T cells, our results provide support for efficacy of MLB in inflammatory diseases and raise its therapeutic potential in activated T cell-mediated pathologies.