Identification of novel mechanisms of silymarin on the carbon tetrachloride-induced liver fibrosis in mice by nuclear factor-κB bioluminescent imaging-guided transcriptomic analysis

Silymarin and Inflammation: Food for Thoughts

Inflammation is a vital defense mechanism, creating hostile conditions for pathogens, preventing the spread of tissue infection and repairing damaged tissues in humans and animals. However, when inflammation resolution is delayed or compromised as a result of its misregulation, the process proceeds from the acute phase to chronic inflammation, leading to the development of various chronic illnesses. It is proven that redox balance disturbances and oxidative stress are among major factors inducing NF-κB and leading to over-inflammation. Therefore, the anti-inflammatory properties of various natural antioxidants have been widely tested in various in vitro and in vivo systems. Accumulating evidence indicates that silymarin (SM) and its main constituent silibinin/silybin (SB) have great potential as an anti-inflammation agent. The main anti-inflammatory mechanism of SM/SB action is attributed to the inhibition of TLR4/NF-κB-mediated signaling pathways and the downregulated expression of pro-inflammatory mediators, including TNF-α, IL-1β, IL-6, IL-12, IL-23, CCL4, CXCL10, etc. Of note, in the same model systems, SM/SB was able to upregulate anti-inflammatory cytokines (IL-4, IL-10, IL-13, TGF-β, etc.) and lipid mediators involved in the resolution of inflammation. The inflammatory properties of SM/SB were clearly demonstrated in model systems based on immune (macrophages and monocytes) and non-immune (epithelial, skin, bone, connective tissue and cancer) cells. At the same time, the anti-inflammatory action of SM/SB was confirmed in a number of in vivo models, including toxicity models, nonalcoholic fatty liver disease, ischemia/reperfusion models, stress-induced injuries, ageing and exercising models, wound healing and many other relevant model systems. It seems likely that the anti-inflammatory activities of SM/SB are key elements on the health-promoting properties of these phytochemicals.

A systematic review of the protective effects of silymarin/silibinin against doxorubicin-induced cardiotoxicity

PURPOSE

Although doxorubicin chemotherapy is commonly applied for treating different malignant tumors, cardiotoxicity induced by this chemotherapeutic agent restricts its clinical use. The use of silymarin/silibinin may mitigate the doxorubicin-induced cardiac adverse effects. For this aim, the potential cardioprotective effects of silymarin/silibinin against the doxorubicin-induced cardiotoxicity were systematically reviewed.

METHODS

In this study, we performed a systematic search in accordance with PRISMA guideline for identifying all relevant studies on "the role of silymarin/silibinin against doxorubicin-induced cardiotoxicity" in different electronic databases up to June 2022. Sixty-one articles were obtained and screened based on the predefined inclusion and exclusion criteria. Thirteen eligible papers were finally included in this review.

RESULTS

According to the echocardiographic and electrocardiographic findings, the doxorubicin-treated groups presented a significant reduction in ejection fraction, tissue Doppler peak mitral annulus systolic velocity, and fractional shortening as well as bradycardia, prolongation of QT and QRS interval. However, these echocardiographic abnormalities were obviously improved in the silymarin plus doxorubicin groups. As well, the doxorubicin administration led to induce histopathological and biochemical changes in the cardiac cells/tissue; in contrast, the silymarin/silibinin co-administration could mitigate these induced alterations (for most of the cases).

CONCLUSION

According to the findings, it was found that the co-administration of silymarin/silibinin alleviates the doxorubicin-induced cardiac adverse effects. Silymarin/silibinin exerts its cardioprotective effects via antioxidant, anti-inflammatory, anti-apoptotic activities, and other mechanisms.

Role of silymarin as antioxidant in clinical management of chronic liver diseases: a narrative review

Chronic liver disease (CLD), manifested as hepatic injury, is a major cause of global morbidity and mortality. CLD progresses to fibrosis, cirrhosis, and-ultimately-hepatocellular carcinoma (HCC) if left untreated. The different phenotypes of CLD based on their respective clinical features and causative agents include alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), metabolic-associated fatty liver disease (MAFLD), and drug-induced liver injury (DILI). The preferred treatment modality for CLD includes lifestyle modification and diet, along with limited pharmacological agents for symptomatic treatment. Moreover, oxidative stress (OS) is an important pathological mechanism underlying all CLD phenotypes; hence, the use of antioxidants to manage the disease is justified. Based on available clinical evidence, silymarin can be utilized as a hepatoprotective agent, given its potent antioxidant, antifibrotic, and anti-inflammatory properties. The role of silymarin in suppressing OS has been well established, and therefore silymarin is recommended for use in ALD and NAFLD in the guidelines approved by the Russian Medical Scientific Society of Therapists and the Gastroenterology Scientific Society of Russia. However, to discuss the positioning of the original silymarin in clinical guidelines and treatment protocols as a hepatoprotective agent for managing CLD concomitantly with other therapies, an expert panel of international and Russian medical professionals was convened on 11 November 2020. The panel reviewed approaches for the prevention and treatment of OS, existing guidelines for patient management for CLD, and available evidence on the effectiveness of silymarin in reducing OS, fibrosis, and hepatic inflammation and presented in the form of a narrative review. Key messagesAn expert panel of international and Russian medical professionals reviewed existing guidelines for ALD, NAFLD, MAFLD, and DILI to establish consensus recommendations that oxidative stress is the common pathophysiological mechanism underlying these conditions.The panel also discussed the positioning of original silymarin in clinical guidelines and treatment protocols as a hepatoprotective agent for managing CLD concomitantly with other therapies.The panel reviewed the effectiveness of 140 mg original silymarin three times a day in reducing oxidative stress in chronic liver diseases such as ALD, NAFLD, MAFLD, and DILI.

D-limonene (5 (one-methyl-four-[1-methylethenyl]) cyclohexane) diminishes CCl4-induced cardiac toxicity by alleviating oxidative stress, inflammatory and cardiac markers

Background: The cardiovascular crisis is advancing rapidly throughout the world. A large number of studies have shown that plant polyphenols affect major mechanisms involved in cardiovascular events through their action on the antioxidant system, signaling, and transcription pathways. D-limonene, a monocyclic monoterpene obtained from citrus fruits, is reported to possess many pharmacological activities.Methods: The experiment was designed to determine the protective effect of D-limonene against cardiac injury induced by CCl4 in Wistar rats. Rats were treated with two doses of D-limonene against cardiac injury induced by CCl4. Serum toxicity markers, cardiac toxicity biomarker enzymes, inflammatory mediators, anti-oxidant armory, lipid peroxidation, lipid profile, and histology were done.Results: CCl4 intoxication resulted in a substantial rise in FFA, TC, TG, PL, LDL, VLDL, and a reduction in HDL, restoring these changes with the administration of D-limonene at a dosage of 200 mg/kg. CCl4 administration also resulted in lipid oxidation and decreased antioxidant activity. At the same time, D-limonene at a dosage of 200 mg/kg body weight inhibited LPO and restored in vivo antioxidant components to normal. CCl4 intoxication also resulted in a significant increase in inflammatory markers like IL-6, TNF-α, high sensitivity Corticotropin Releasing Factor (Hs-CRF), and biomarkers of cardiac toxicity like alanine aminotransferase (ALT), lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase MB (CKMB), and Troponin I & troponin-t activities. D-limonene reversed all these changes to normal. Histology further confirmed our obtained results.Conclusion: These findings indicate that D-limonene can ameliorate cardiac injury at a 200 mg/kg body weight dosage. Henceforth, D-Limonene intervenes in mediating CCl4 induced toxicity by various signaling pathways.

Regulatory Networks, Management Approaches, and Emerging Treatments of Nonalcoholic Fatty Liver Disease

The pathogenesis of NAFLD is complex and diverse, involving multiple signaling pathways and cytokines from various organs. Hepatokines, stellakines, adipokines, and myokines secreted by hepatocytes, hepatic stellate cells, adipose tissue, and myocytes play an important role in the occurrence and development of nonalcoholic fatty liver disease (NAFLD). The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) contributes to the progression of NAFLD by mediating liver inflammation, immune response, hepatocyte death, and later compensatory proliferation. In this review, we first discuss the crosstalk and interaction between hepatokines, stellakines, adipokines, and myokines and NF-κB in NAFLD. The characterization of the crosstalk of NF-κB with these factors will provide a better understanding of the molecular mechanisms involved in the progression of NAFLD. In addition, we examine new expert management opinions for NAFLD and explore the therapeutic potential of silymarin in NAFLD/NASH.

HMGB1 induced endothelial to mesenchymal transition in liver fibrosis: The key regulation of early growth response factor 1

BACKGROUND

Liver fibrosis has been the focus and difficulty of medical research in the world and its concrete pathogenesis remains unclear. This study aims to observe the high-mobility group box 1 (HMGB1)-induced hepatic endothelial to mesenchymal transition (EndoMT) during the development of hepatic fibrosis, and further to explore the crucial involvement of Egr1 in this process.

METHODS

Carbon tetrachloride (CCl₄), diosbulbin B (DB), N-acetyl-p-aminophenol (APAP) and bile duct ligation (BDL) were used to induce liver fibrosis in mice. Serum HMGB1 content, the occurrence of EndoMT and the production of extracellular matrix (ECM) in vitro and in vivo were detected by Western-blot.

RESULTS

The elevated serum HMGB1 content, the occurrence of EndoMT, the production of ECM and the activation of Egr1 were observed in mice with liver fibrosis induced by CCl₄, DB, APAP or BDL. HMGB1 induced EndoMT and ECM production in human hepatic sinusoidal endothelial cells (HHSECs), and then HHSECs lost the ability to inhibit the activation of hepatic stellate cells (HSCs). The hepatic deposition of collagen, the increased serum HMGB1 content and hepatic EndoMT were further aggravated in Egr1 knockout mice. Natural compound silymarin attenuated liver fibrosis in mice induced by CCl₄ via increasing Egr1 nuclear accumulation, decreasing serum HMGB1 content and inhibiting hepatic EndoMT.

CONCLUSION

Egr1 regulated the expression of HMGB1 that induced hepatic EndoMT, which plays an important role in the development of liver fibrosis.

GENERAL SIGNIFICANCE

This study provides a novel therapeutic strategy for the treatment of liver fibrosis in clinic.

Mitochondrial Dysfunction and Oxidative Stress in Liver Transplantation and Underlying Diseases: New Insights and Therapeutics

Mitochondria are essential organelles for cellular energy and metabolism. Like with any organ, the liver highly depends on the function of these cellular powerhouses. Hepatotoxic insults often lead to an impairment of mitochondrial activity and an increase in oxidative stress, thereby compromising the metabolic and synthetic functions. Mitochondria play a critical role in ATP synthesis and the production or scavenging of free radicals. Mitochondria orchestrate many cellular signaling pathways involved in the regulation of cell death, metabolism, cell division, and progenitor cell differentiation. Mitochondrial dysfunction and oxidative stress are closely associated with ischemia-reperfusion injury during organ transplantation and with different liver diseases, including cholestasis, steatosis, viral hepatitis, and drug-induced liver injury. To develop novel mitochondria-targeting therapies or interventions, a better understanding of mitochondrial dysfunction and oxidative stress in hepatic pathogenesis is very much needed. Therapies targeting mitochondria impairment and oxidative imbalance in liver diseases have been extensively studied in preclinical and clinical research. In this review, we provide an overview of how oxidative stress and mitochondrial dysfunction affect liver diseases and liver transplantation. Furthermore, we summarize recent developments of antioxidant and mitochondria-targeted interventions.

Coenzyme Q10 and Silymarin Reduce CCl4-Induced Oxidative Stress and Liver and Kidney Injury in Ovariectomized Rats—Implications for Protective Therapy in Chronic Liver and Kidney Diseases

Oxidative stress is one of the key factors in the pathophysiology of liver disease. The present study aimed to evaluate the potential impact of two antioxidants, namely coenzyme Q10 (CoQ10) and silymarin, on carbon tetrachloride (CCl₄)-induced oxidative stress and hepatic damage in ovariectomized rats. Female Long Evans rats were divided into six groups (n = 6): control, CCl₄, CCl₄ + CoQ10 (200 mg/kg), CCl₄ + silymarin (140 mg/kg), Control + CoQ10, and Control + silymarin. Plasma and tissues from liver and kidney were analyzed for oxidative stress parameters and antioxidant enzyme activities using biochemical assays. Infiltration of inflammatory cells and fibrosis were assessed by histological staining of tissue sections. Both CoQ10 and silymarin significantly lowered serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) levels that were detected to be higher in CCl₄ rats compared to controls. Significant reduction in CCl₄-induced elevated levels of oxidative stress markers malondialdehyde (MDA), nitric oxide (NO), and advanced protein oxidation product (APOP) was observed with both antioxidants. However, in control rats, CoQ10 and silymarin did not produce a significant effect. Histological analysis revealed that CCl₄ markedly increased the level of inflammatory cells infiltration and fibrosis in liver and kidney tissues, but this was significantly reduced in CCl₄ + CoQ10 and CCl₄ + silymarin groups. Taken together, our results suggest that CoQ10 and silymarin can protect the liver against oxidative damage through improved antioxidant enzyme activities and reduced lipid peroxidation. Thus, supplementation of the aforementioned antioxidants may be useful as a therapeutic intervention to protect liver health in chronic liver diseases.

Metabolic profiling and in vivo hepatoprotective activity of Malpighia glabra L. leaves

Although Malpighia glabra Linn. fruits are well studied for their nutritional and medicinal prominence; little attention has been given to the leaves. Our study intends to investigate the leaves metabolic profile using Q-TOF LC/MS/MS (Quadrupole-Time-of-Flight-Liquid-Chromatography-Mass-Spectrometry), and to explore their in vivo hepatoprotective activity in rats using CCL₄ -induced hepatic damage model and silymarin as standard. Fifty metabolites were characterized, belonging to different classes; coumarins (capensine, daphnoretin, and scopoletin), flavonoids (mainly quercetin and apigenin glycosides), phenolic acids (cinnamic acid and quinic acid derivatives) and amino acids (adenosine, homoisoleucine, and phenylalanine).These compounds are detected in the leaves for the first time. The hepatoprotective activity at three doses (200, 400, and 800 mg/kg) was investigated. The dose of 800 mg/Kg showed the highest hepatoprotective effect as it reduced the elevated serum levels of ALT, AST, NO, and TNF-α liver content by 26, 24, 23, and 42%, respectively, it also remarkably increased the serum level of catalase by 102%. All the tested doses showed higher reduction in serum level of TNF-α compared to silymarin which suggests their strong anti-inflammatory potential. M. glabra leaves are revealed to be a rich source of secondary metabolites and proved to possess significant hepatoprotective potential. PRACTICAL APPLICATIONS: The performed analyses in this study shows the richness of Malpighia glabra Linn. leaves in a plethora of beneficial and safe phytochemicals which are well-known to have a pivotal role in protection against different diseases including liver disorders. The carried-out investigations were done using Q-TOF LC/MS/MS analysis which is a reliable technique for the determination, characterization and identification of bioactive metabolites; in addition to evaluation of the hepatoprotective effect of the leaves. Therefore, this study may emphasize that Malpighia glabra Linn. leaves may have the same nutritional and medicinal importance as its fruits, and they could be incorporated into pharmaceuticals and foods instead of discarding them.

The beneficial effects of antioxidants combination on cardiac injury induced by tetrachloromethane

The purpose of this research was to evaluate the efficacy of carsil (CAR) either alone or in combination with α-tocopherol (α-TOCO) and/or turmeric (TUMR) against tetrachloromethane (TCM)-induced cardiomyocyte injury in rats. Administration of CAR either alone or in combination with α-TOCO and/or TUMR post-TCM injection, significantly mitigated the increases in serum troponin T, creatine kinase-MB (CK-MB) as well as interleukin-6 (IL-6), interferon γ (IFN-γ), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP). They also decline the elevation of caspase-3, vascular endothelial growth factor (VEGF) protein expression as well as DNA damage in cardiac tissues induced by TCM. The biochemical results were confirmed by histopathological investigation. Conclusion: The combination of the three antioxidants showed greater cardioprotective potential, compared to individual drugs. Therefore, this combination may be recommended as a complementary therapy to antagonize cardiac injury induced by different insults.

Suaeda vermiculata Aqueous-Ethanolic Extract-Based Mitigation of CCl4-Induced Hepatotoxicity in Rats, and HepG-2 and HepG-2/ADR Cell-Lines-Based Cytotoxicity Evaluations

Suaeda vermiculata, an edible halophytic plant, used by desert nomads to treat jaundice, was investigated for its hepatoprotective bioactivity and safety profile on its mother liquor aqueous-ethanolic extract. Upon LC-MS (Liquid Chromatography-Mass Spectrometry) analysis, the presence of several constituents including three major flavonoids, namely quercetin, quercetin-3-O-rutinoside, and kaempferol-O-(acetyl)-hexoside-pentoside were confirmed. The aqueous-ethanolic extract, rich in antioxidants, quenched the DPPH (1,1-diphenyl-2-picrylhydrazyl) radicals, and also showed noticeable levels of radical scavenging capacity in ABTS (2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid) assay. For the hepatoprotective activity confirmation, the male rat groups were fed daily, for 7 days (n = 8/group, p.o.), either carboxyl methylcellulose (CMC) 0.5%, silymarin 200 mg/kg, the aqueous-ethanolic extract of the plant Suaeda vermiculata (100, 250, and 500 mg/kg extract), or quercetin (100 mg/kg) alone, and on day 7 of the administrations, all the animal groups, excluding a naïve (250 mg/kg aqueous-ethanolic extract-fed), and an intact animal group were induced hepatotoxicity by intraperitoneally administering carbon tetrachloride (CCl₄). All the animals were sacrificed after 24 h, and aspartate transaminase and alanine transaminase serum levels were observed, which were noted to be significantly decreased for the aqueous-ethanolic extract, silymarin, and quercetin-fed groups in comparison to the CMC-fed group (p < 0.0001). No noticeable adverse effects were observed on the liver, kidney, or heart's functions of the naïve (250 mg/kg) group. The aqueous-ethanolic extract was found to be safe in the acute toxicity (5 g/kg) test and showed hepatoprotection and safety at higher doses. Further upon, the cytotoxicity testings in HepG-2 and HepG-2/ADR (Adriamycin resistant) cell-lines were also investigated, and the IC₅₀ values were recorded at 56.19±2.55 µg/mL, and 78.40±0.32 µg/mL (p < 0.001, Relative Resistance RR 1.39), respectively, while the doxorubicin (Adriamycin) IC₅₀ values were found to be 1.3±0.064, and 4.77±1.05 µg/mL (p < 0.001, RR 3.67), respectively. The HepG-2/ADR cell-lines when tested in a combination of the aqueous-ethanolic extract with doxorubicin, a significant reversal in the doxorubicin's IC₅₀ value by 2.77 folds (p < 0.001, CI = 0.56) was noted as compared to the cytotoxicity test where the extract was absent. The mode of action for the reversal was determined to be synergistic in nature indicating the role of the aqueous-ethanolic extract.

Bidens pilosa L. (Asteraceae) cultivated in Brazil on acute liver disease in dogs

ABSTRACT Bidens pilosa L. is a medicinal plant popularly used for treatment of liver diseases. In this study, the dry extract of aerial parts of Bidens pilosa and Silymarin, a phytocomplex obtained from the Silybum marianum fruits and marketed as hepatoprotective, were tested in dogs experimentally acutely intoxicated with carbon tetrachloride. The liver activity was evaluated by hematological and biochemical profiles, and histological and ultrasound analyzes. It was observed that the lowest serum activities of ALT and serum concentrations of total bilirubin occurred in the groups treated with the dry extract of Bidens pilosa, while only decreased serum concentrations of total bilirubin occurred in the group treated with Silymarin. Best liver recovery was also observed for the dry extract of B. pilosa at a 400mg/Kg dose by ultrasonography. This study showed that the dry extract of Bidens pilosa acted more efficiently in the treatment of acute toxic hepatitis induced in dogs than Silymarin.

Aescin and diosmin each alone or in low dose- combination ameliorate liver damage induced by carbon tetrachloride in rats

Objective

This study evaluated hepatoprotective effect of aescin (AES) and diosmin (DIO), individually or in low-dose combination in chemically induced liver injury in rats. Rats were divided into 6 groups; Group 1, control, Group 2, injected with a single dose of a mixture of corn oil and carbon tetrachloride (CCl₄) to induce hepatic toxicity. Before CCl₄ injection, Groups 3–6 were treated daily for 14 days with silymarin (SIL) (200 mg/kg), aescin (AES; 3.6 & 1.75 mg/kg), Diosmin (DIO; 100 & 50 mg/kg). Serum samples were analyzed for different liver function, oxidative stress and antioxidant markers. Moreover, inflammation and tissue damage were confirmed by histological staining of liver tissue sections.

Results

Results indicated that CCl₄ elevated serum levels of all assessed liver function markers and decreased levels of key antioxidants. Administration of AES and/or DIO significantly reversed all those CCl₄-induced effects. Histopathological study showed disruption of the hepatic architecture, necrosis and inflammatory cells and depositions of glycogen and protein in the tissues of CCl₄-treated group. Pretreatment with DIO and/or AES significantly improved histopathological structure of liver tissue. In conclusion, low-dose combination of AES and DIO exhibited significant and preferential hepatoprotective activity compared to individual treatment with AES or DIO.

Silymarin as Supportive Treatment in Liver Diseases: A Narrative Review

Silymarin, an extract from milk thistle seeds, has been used for centuries to treat hepatic conditions. Preclinical data indicate that silymarin can reduce oxidative stress and consequent cytotoxicity, thereby protecting intact liver cells or cells not yet irreversibly damaged. Eurosil 85® is a proprietary formulation developed to maximize the oral bioavailability of silymarin. Most of the clinical research on silymarin has used this formulation. Silymarin acts as a free radical scavenger and modulates enzymes associated with the development of cellular damage, fibrosis and cirrhosis. These hepatoprotective effects were observed in clinical studies in patients with alcoholic or non-alcoholic fatty liver disease, including patients with cirrhosis. In a pooled analysis of trials in patients with cirrhosis, silymarin treatment was associated with a significant reduction in liver-related deaths. Moreover, in patients with diabetes and alcoholic cirrhosis, silymarin was also able to improve glycemic parameters. Patients with drug-induced liver injuries were also successfully treated with silymarin. Silymarin is generally very well tolerated, with a low incidence of adverse events and no treatment-related serious adverse events or deaths reported in clinical trials. For maximum benefit, treatment with silymarin should be initiated as early as possible in patients with fatty liver disease and other distinct liver disease manifestations such as acute liver failure, when the regenerative potential of the liver is still high and when removal of oxidative stress, the cause of cytotoxicity, can achieve the best results.

Dietary supplementation of Pleurotus tuber regium in rat feed ameliorates metabolic and hematotoxicity induced by carbon tetrachloride

Pleurotus tuber regium, a wild edible mushroom can reduce free radical-mediated injury and oxidative stress induced by carbon tetrachloride (CCl4) via improvement of antioxidant capacity. This work evaluates the protective effects of this mushroom against the metabolic and hematological toxicity induced by CCl4. Sixty male Sprague Dawley rats were divided into six groups (n = 10). Group I received olive oil (3 mL/kg) i.p. twice weekly for 13 weeks, while maintaining free access to food and water ad libitum (negative control). Group II received 3 mL/kg (30% CCl4 in olive oil) injected i.p. twice weekly, while Groups III, IV, and V received 100, 200, and 500 mg wild edible P. tuber regium (33.3% in feed) daily in addition to 3 mL/kg CCl4 in olive oil injected twice weekly i.p. Group VI received olive oil (3 mL/kg) i.p. twice weekly for 13 weeks in addition to 500 mg P. tuber regium (33.3% in feed) daily. The body weight (b.w.), feed intake (FI), and water intake (WI) were obtained weekly, while the hematological indices and oxidative stress parameters were carried out shortly after necropsy on days 30, 60, and 90. Treatment with CCl4 significantly (p < 0.05) decreased the b.w., FI and WI, feed efficiency, ascorbic acid, α-tocopherol, and antioxidant enzymes, superoxide dismutase, catalase, total glutathione, and peroxidase, while increasing the oxidative stress as measured by malondialdehyde in CCl4 only group when compared with control. Supplementation of feed with P. tuber regium reversed the effects of CCl4. Pleurotus tuber regium ameliorated the CCl4-induced metabolic and hematotoxicity by improving the antioxidant capacity.

The protective effect of quercetin on retinal inflammation in mice: the involvement of tumor necrosis factor/nuclear factor-κB signaling pathways

Oral administration of quercetin ameliorated LPS-induced retinal inflammation in mice by down-regulating TNF, cytokine, and NF-κB pathways.

Cross Talk Between TGF-β and JAK Expressions and Nepherotoxicity Induced by Tetrachloromethane: Role of Phytotherapy

The aim of the current study is to assess the effectiveness of milk thistle seeds (Mth) in combination with Taraxacum officinale (Tof) and/or Camellia sinensis (Csin) against tetrachloromethane (Tcm) renotoxicity in rats. Tetrachloromethane was injected in a single dose, followed by 1-month treatments with Mth, Tof, and Csin alone or in combination. Serum urea, uric acid, and creatinine levels were significantly increased matched with the control group. Masson trichrome stain revealed increase in the deposition of fibrous tissue in the interstitium between the tubules and the renal corpuscles. Immunohistochemical analysis of kidney tissues revealed that Tcm induced an increase in the immune response of tumor growth factor β (TGF-β) and Janus kinase (JAK) protein expressions and cysteine–aspartic acid protease 3 (caspase 3), while B-cell lymphoma 2 (Bcl2) was downregulated. Treatment with the antioxidants in question either alone or in combination ameliorated all kidney function parameters and showed mild immune reactivity toward TGF-β and JAK protein expressions in blood vessels and glomeruli in the kidney tissues and downregulated caspase 3 and activated Bcl2 protein expression. The combination regimen of the 3 antioxidants showed the most significant renoprotective effect. This was also confirmed histopathologically. It was concluded that the antioxidant mixture is considered as a promising candidate toward renal dysfunction and immune reactivity induced by Tcm and other toxicants.

Milk thistle (Silybum marianum): A concise overview on its chemistry, pharmacological, and nutraceutical uses in liver diseases

Milk thistle (MT; Silybum marianum), a member of the Asteraceae family, is a therapeutic herb with a 2,000-year history of use. MT fruits contain a mixture of flavonolignans collectively known as silymarin, being silybin (also named silibinin) the main component. This article reviews the chemistry of MT, the pharmacokinetics and bioavailability, the pharmacologically relevant actions for liver diseases (e.g., anti-inflammatory, immunomodulating, antifibrotic, antioxidant, and liver-regenerating properties) as well as the clinical potential in patients with alcoholic liver disease, nonalcoholic fatty liver disease, viral hepatitis, drug-induced liver injury, and mushroom poisoning. Overall, literature data suggest that, despite encouraging preclinical data, further well-designed randomized clinical trials are needed to fully substantiate the real value of MT preparations in liver diseases.

Protective effects of Mentha piperita L. leaf essential oil against CCl4 induced hepatic oxidative damage and renal failure in rats

Background

Mentha piperita L. is a flowering plant belonging to the Lamiaceae family. Mentha plants constitute one of the main valuable sources of essential oil used in foods and for medicinal purposes.

Methods

The present study aimed to investigate the composition and in vitro antioxidant activity of Mentha piperita leaf essential oil (MpEO). A single dose of CCl₄ was used to induce oxidative stress in rats, which was demonstrated by a significant rise of serum enzyme markers. MpEO was administrated for 7 consecutive days (5, 15, 40 mg/kg body weight) to Wistar rats prior to CCl₄ treatment and the effects on serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and γ -glutamyl transpeptidase (γ-GT) levels, as well as the liver and kidney superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activity and thiobarbituric acid reactive substances (TBARS) levels were evaluated. In addition, histopathological examinations of livers and kidneys was performed.

Results

The in vitro antioxidant activity of MpEO was lower than that of silymarin. Pretreatment of animals with MpEO at a dose of 5 mg/kg did not have a significant effect on ALT, AST, ALP, LDH, γGT, urea or creatinine levels in CCl₄-induced stress. Whereas pretreatment with MpEO at doses of 15 and 40 mg/kg prior to CCl₄, significantly reduced stress parameters (ALT, AST, ALP, LDH, γGT, urea and creatinine) compared to the CCl₄-only group. Moreover, a significant reduction in hepatic and kidney lipid peroxidation (TBARS) and an increase in antioxidant enzymes SOD, CAT and GPx was also observed after treatment with MpEO (40 mg/kg) compared to CCl₄-treated rats. Furthermore, pretreatment with MpEO at 40 mg/kg can also markedly ameliorate the histopathological hepatic and kidney lesions induced by administration of CCl₄.

Conclusions

We could demonstrate with this study that MpEO protects liver and kidney from CCl₄-induced oxidative stress and thus substantiate the beneficial effects attributed traditionally to this plant.

Role of Different Natural Antioxidants in the Modulation of mRNA-expression of Apoptotic Molecules in the Livers of Carbon Tetrachloride-Intoxicated Rats

Overexpression of nuclear factor (NF-κB) or activation of Smad3 by transforming growth factor β (TGF-β1) induced by oncogenes results in overexpression of fibrotic processes and hence cell death. The objective of this study is to examine whether Silymarin (Sil) alone or in combination with Vitamin E (Vit E) and/or Curcumin (Cur) plays a modulatory role against the overexpression of NF-κB, and TGF-β that induced in response to carbon tetrachloride (CCl₄) administration. The present work revealed that CCl₄ induced elevation of in serum alanine aminotransferase (ALT), Apoptosis regulator (Bax), Smad3, TGF-β, and NF-kB hepatic mRNA expression (using Real-time PCR), administration of Sil alone downregulated these expressions. Treatment with Vit E acid and/ or Cur along with Sil produced best results in this concern. B-cell lymphoma 2 (Bcl-2) expressions were downregulated by CCl₄; whereas concurrent treatment of Vit E and/or Cur along with Sil increased its expression. On conclusion, the use of Vit E and/or Cur could potentiate the antiapoptotic action of Sil.

Beneficial Effects of Silymarin After the Discontinuation of CCl4-Induced Liver Fibrosis

Silymarin (Si) is a herbal product with hepatoprotective potential, well-known for its antioxidant, anti-inflammatory, and immunomodulatory properties. We have recently demonstrated that the usual therapeutic doses of Si are capable of inhibiting the progression of incipient liver fibrosis. We aimed at further investigating the benefits of Si administration upon liver alterations after the hepatotoxin discontinuation, using CCl4 to induce liver injuries on rats. CCl4 administration induces first of all oxidative stress, but other mechanisms, such as inflammation and liver fibrosis are also triggered. Fifty Wistar rats were randomly divided into five groups (n = 10). The control group received sunflower oil twice a week for 8 weeks. Carboxymethyl cellulose group received sunflower oil twice a week, for 8 weeks and CMC daily, for the next 2 weeks. CCl4 group received CCl4 in sunflower oil, by gavage, twice a week, for 8 weeks. CCl4 + Si 50 group received CCl4 twice a week, for 8 weeks, and then 50 mg/body weight (b.w.) Silymarin for the next 2 weeks. CCl4 + Si 200 group was similar to the previous group, but with Si 200 mg/b.w. Ten weeks after the experiment had begun, we assessed inflammation (IL-6, MAPK, NF-κB, pNF-κB), fibrosis (hyaluronic acid), TGF-β1, MMP-9, markers of hepatic stellate cell activation (α-SMA expression), and proliferative capacity (proliferating cell nuclear antigen). Our data showed that Silymarin administered after the toxic liver injury is capable of reducing inflammation and liver fibrosis. The benefits were more important for the higher dose than for the usual therapeutic dose.

Hepatoprotective standardized EtOH-water extract from the seeds of Fraxinus rhynchophylla Hance

Fraxinus rhynchophylla Hance (Oleaceae), its stem barks are known as Cortex fraxini (秦皮 qín pí) listed in Chinese Pharmacopoeia. Phytochemical study has indicated that methanol extracts from Qinpi has protective effect on acute liver injury. The present study investigates the hepatoprotective activity of EtOH–water extract from the seeds of F. rhynchophylla Hance against carbon tetrachloride-induced liver injury in mice. The EtOH–water extract significantly alleviated liver damage as indicated by the decreased levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), the malondialdehyde (MDA) content, and increased the levels of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GSH-Px), and reduced the pathological tissue injury induced by CCl₄. Quantitative analysis of seven major constituents (1–7) in EtOH–water extract (EWE) was developed by high performance liquid chromatography-diode-array detector (HPLC-DAD). The current research indicates that the EWE from the seeds of F. rhynchophylla Hance decreased liver index, inhibited the increase of serum aminotransferase induced by CCl₄, and decreased hepatic MDA content, SOD and GSH-Px activities. These results suggested that the pretreatment with EWE protected mice against CCl₄-induced liver injuries. Based on the results, the EtOH–water extract from the seeds of F. rhynchophylla Hance is efficacious for prevention and treatment of CCl₄-induced hepatic injury in mice. Secoiridoid and tyrosol glucosides might be the active ingredients responsible for the biological and pharmacological activities of hepatoprotection.

Therapeutic efficacy of ethanolic extract of Aerva javanica aerial parts in the amelioration of CCl4-induced hepatotoxicity and oxidative damage in rats

Background

Liver diseases, the fifth most common cause of global death, can be metabolic, toxin-induced, or infective. Though approximately 35 Saudi medicinal plants are traditionally used to treat liver disorders, the hepatoprotective potential of Aerva javanica has not been explored.

Objective

To investigate the antioxidative and hepatoprotective effect of Aerva javanica.

Design

Total ethanol extract of A. javanica aerial parts was prepared and tested on DCFH-toxicated HepG2 cells ex vivo, and in CCl₄-injured Wistar rats in vivo. MTT assay was used to determine cell viability and the serum biochemical markers of liver injury as well as histopathology was performed. In vitro 1,1-diphenyl-2-picrylhydrazyl and β-carotene free-radical scavenging assay and phytochemical screening of the extract were done. Furthermore, A. javanica total extract was standardized and validated by high-performance thin layer chromatographic method.

Results

MTT assay showed that, while DCFH-injured cells were recovered to ~56.7% by 100 µg/ml of the extract, a 200 µg/ml dose resulted in hepatocytes recovery by ~90.2%. Oral administration of the extract (100 and 200 mg/kg.bw/day) significantly normalized the serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, gamma-glutamyl transferase, alkaline phosphatase, bilirubin, cholesterol, high-density lipoprotein, low-density lipoprotein, very-low-density lipoprotein, triglyceride, and malondialdehyde levels, including tissue nonprotein sulfhydryl and total protein in CCl₄-injured rats. In addition, the histopathology of dissected liver also revealed that A. javanica cured the tissue lesion compared to silymarin treatment. In vitro assays revealed strong free-radical scavenging ability of the extract and presence of alkaloids, flavonoids, tannins, sterols, and saponins where rutin, a well-known antioxidant flavonoid, was identified.

Conclusions

Our findings demonstrate the potential of A. javanica in the attenuation of ex vivo and in vivo hepatotoxicity and oxidative damage. This further suggests its therapeutic value in various liver diseases. However, isolations of the active principles, their mechanisms of action, and other therapeutic contributions remain to be addressed.

Ginger and Zingerone Ameliorate Lipopolysaccharide-Induced Acute Systemic Inflammation in Mice, Assessed by Nuclear Factor-κB Bioluminescent Imaging

Ginger is a commonly used spice in cooking. In this study, we comprehensively evaluated the anti-inflammatory activities of ginger and its component zingerone in lipopolysaccharide (LPS)-induced acute systemic inflammation in mice via nuclear factor-κB (NF-κB) bioluminescent imaging. Ginger and zingerone significantly suppressed LPS-induced NF-κB activities in cells in a dose-dependent manner, and the maximal inhibition (84.5% ± 3.5% and 96.2% ± 0.6%) was observed at 100 μg/mL ginger and zingerone, respectively. Moreover, dietary ginger and zingerone significantly reduced LPS-induced proinflammatory cytokine production in sera by 62.9% ± 18.2% and 81.3% ± 6.2%, respectively, and NF-κB bioluminescent signals in whole body by 26.9% ± 14.3% and 38.5% ± 6.2%, respectively. In addition, ginger and zingerone suppressed LPS-induced NF-κB-driven luminescent intensities in most organs, and the maximal inhibition by ginger and zingerone was observed in small intestine. Immunohistochemical staining further showed that ginger and zingerone decreased interleukin-1β (IL-1β)-, CD11b-, and p65-positive areas in jejunum. In conclusion, our findings suggested that ginger and zingerone were likely to be broad-spectrum anti-inflammatory agents in most organs that suppressed the activation of NF-κB, the production of IL-1β, and the infiltration of inflammatory cells in mice.

Hepatoprotective and antiviral efficacy of Acacia mellifera leaves fractions against hepatitis B virus

The present study investigated the hepatoprotective and anti-HBV efficacy of Acacia mellifera (AM) leaves extracts. The crude ethanolic-extract, including organic and aqueous fractions, were tested for cytotoxicity on HepG2 and HepG2.2.15 cells (IC₅₀ = 684 μg/mL). Of these, the ethyl acetate and aqueous fractions showed the most promising, dose-dependent hepatoprotection in DCFH-toxicated cells at 48 h. In CCl₄-injured rats, oral administration of AM ethanol extract (250 and 500 mg/kg·bw) for three weeks significantly normalized the sera aminotransferases, alkaline phosphatase, bilirubin, cholesterol, triglycerides, and lipoprotein levels and elevated tissue nonprotein sulphydryl and total protein. The histopathology of dissected livers also revealed that AM cured the tissue lesions. The phytochemical screening of the fractions showed presence of alkaloids, flavonoids, tannins, sterols, and saponins. Further, anti-HBV potential of the fractions was evaluated on HepG2.2.15 cells. Of these, the n-butanol and aqueous fractions exhibited the best inhibitory effects on HBsAg and HBeAg expressions in dose- and time-dependent manner. Taken together, while the ethyl acetate and aqueous fractions exhibited the most promising antioxidant/hepatoprotective and anti-HBV activity, respectively, the n-butanol partition showed both activities. Therefore, the therapeutic potential of AM extracts warrants further isolation of the active principle(s) and its phytochemical as well as biological studies.

Silymarin as a Natural Antioxidant: An Overview of the Current Evidence and Perspectives

Silymarin (SM), an extract from the Silybum marianum (milk thistle) plant containing various flavonolignans (with silybin being the major one), has received a tremendous amount of attention over the last decade as a herbal remedy for liver treatment. In many cases, the antioxidant properties of SM are considered to be responsible for its protective actions. Possible antioxidant mechanisms of SM are evaluated in this review. (1) Direct scavenging free radicals and chelating free Fe and Cu are mainly effective in the gut. (2) Preventing free radical formation by inhibiting specific ROS-producing enzymes, or improving an integrity of mitochondria in stress conditions, are of great importance. (3) Maintaining an optimal redox balance in the cell by activating a range of antioxidant enzymes and non-enzymatic antioxidants, mainly via Nrf2 activation is probably the main driving force of antioxidant (AO)  action of SM. (4) Decreasing inflammatory responses by inhibiting NF-κB pathways is an emerging mechanism of SM protective effects in liver toxicity and various liver diseases. (5) Activating vitagenes, responsible for synthesis of protective molecules, including heat shock proteins (HSPs), thioredoxin and sirtuins and providing additional protection in stress conditions deserves more attention. (6) Affecting the microenvironment of the gut, including SM-bacteria interactions, awaits future investigations. (7) In animal nutrition and disease prevention strategy, SM alone, or in combination with other hepatho-active compounds (carnitine, betaine, vitamin B₁₂, etc.), might have similar hepatoprotective effects as described in human nutrition.

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.

In vivo efficacy study of milk thistle extract (ETHIS-094™) in STAM™ model of nonalcoholic steatohepatitis

INTRODUCTION

A subcategory of nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH) is characterized by accumulation of fat accompanied by inflammatory infiltration and hepatocellular damage. The active complex of milk thistle is a lipophilic extract from its seeds, comprising three isomers, collectively known as silymarin. Silymarin has demonstrated antioxidant, anti-inflammatory, and antifibrotic properties, and has been extensively studied in the treatment of liver diseases. The majority of published clinical research on silymarin has used Legalon(®) (Rottapharm/Madaus), containing the patented extract of milk thistle ETHIS-094™ (Euromed). The current study was undertaken to examine the effects of ETHIS-094™ in the Stelic Animal Model (STAM™), a validated and widely used animal model for NASH.

METHODS

After 4 h fasting from 4 to 8 weeks of age, 15 male mice in whom NASH had been induced were orally administered, once daily, either (1) vehicle (saline) at a volume of 10 mL/kg, (2) vehicle supplemented with milk thistle at a dose of 500 mg/kg, or (3) vehicle supplemented with milk thistle at a dose of 1,000 mg/kg.

RESULTS

Mean liver weight and the liver-to-body weight ratio were significantly (P < 0.01) decreased in the milk thistle high-dose group compared with the vehicle group. NAFLD activity score (NAS) tended to decrease in the milk thistle treatment groups compared with vehicle group, as did steatosis scores.

CONCLUSION

Milk thistle extract administration induced a decreasing trend in NAS compared with the vehicle group. Milk thistle induced a numerical decrease of the steatosis score compared with vehicle, and this was accompanied by a statistically significant decrease in liver weight and the liver-to-body weight ratio, implying a potential anti-steatosis effect of milk thistle.

Delivery and targeting of miRNAs for treating liver fibrosis

Liver fibrosis is a pathological condition originating from liver damage that leads to excess accumulation of extracellular matrix (ECM) proteins in the liver. Viral infection, chronic injury, local inflammatory responses and oxidative stress are the major factors contributing to the onset and progression of liver fibrosis. Multiple cell types and various growth factors and inflammatory cytokines are involved in the induction and progression of this disease. Various strategies currently being tried to attenuate liver fibrosis include the inhibition of HSC activation or induction of their apoptosis, reduction of collagen production and deposition, decrease in inflammation, and liver transplantation. Liver fibrosis treatment approaches are mainly based on small drug molecules, antibodies, oligonucleotides (ODNs), siRNA and miRNAs. MicroRNAs (miRNA or miR) are endogenous noncoding RNA of ~22 nucleotides that regulate gene expression at post transcription level. There are several miRNAs having aberrant expressions and play a key role in the pathogenesis of liver fibrosis. Single miRNA can target multiple mRNAs, and we can predict its targets based on seed region pairing, thermodynamic stability of pairing and species conservation. For in vivo delivery, we need some additional chemical modification in their structure, and suitable delivery systems like micelles, liposomes and conjugation with targeting or stabilizing the moiety. Here, we discuss the role of miRNAs in fibrogenesis and current approaches of utilizing these miRNAs for treating liver fibrosis.

Potential impact of silymarin in combination with chlorogenic acid and/or melatonin in combating cardiomyopathy induced by carbon tetrachloride

The aim of this study was to investigate the effective role of silymarin either alone or in combination with chlorogenic acid and/or melatonin against the toxic impact of carbon tetrachloride (CCl4) induced cardiac infarction. CCl4 (l.2 ml/kg body weight) was administered as a single dose intraperitoneally. The results revealed that the administration of silymarin alone or in combination with chlorogenic acid (CGA) and/or melatonin for 21 consecutive days, 24 h after CCl4 injection to rats, markedly ameliorated the increases in serum markers of cardiac infarction, including troponin T and creatine kinase-MB (CK-MB), as well as increases in the pro-inflammatory biomarkers, including interleukin-6 (IL-6), interferon-γ (IFN-γ) in serum and tumor necrosis factor-α (TNF-α) and C-reactive protein in cardiac tissue compared to CCl4 intoxicated rats. The used agents also successfully modulated the alteration in vascular endothelial growth factor (VEGF) in serum and the oxidative DNA damage and the increase in the apoptosis marker caspase 3 in cardiac tissue in response to CCl4 toxicity. The present biochemical results are supported by histo-pathological examination. The current results proved that treatment with silymarin in combination with CGA and melatonin was the most effective one in ameliorating the toxicity of CCl4 induced cardiac damage and this may support the use of this combination as an effective drug to treat cardiac damage induced by toxic agents.

Application of transcriptomics in Chinese herbal medicine studies

Transcriptomics using DNA microarray has become a practical and popular tool for herbal medicine study because of high throughput, sensitivity, accuracy, specificity, and reproducibility. Therefore, this article focuses on the overview of DNA microarray technology and the application of DNA microarray in Chinese herbal medicine study. To understand the number and the objectives of articles utilizing DNA microarray for herbal medicine study, we surveyed 297 frequently used Chinese medicinal herbs listed in Pharmacopoeia Commission of People's Republic of China. We classified these medicinal herbs into 109 families and then applied PudMed search using “microarray” and individual herbal family as keywords. Although thousands of papers applying DNA microarray in Chinese herbal studies have been published since 1998, most of the articles focus on the elucidation of mechanisms of certain biological effects of herbs. Construction of the bioactivity database containing large-scaled gene expression profiles of quality control herbs can be applied in the future to analyze the biological events induced by herbs, predict the therapeutic potential of herbs, evaluate the safety of herbs, and identify the drug candidate of herbs. Moreover, the linkage of systems biology tools, such as functional genomics, transcriptomics, proteomics, metabolomics, pharmacogenomics and toxicogenomics, will become a new translational platform between Western medicine and Chinese herbal medicine.

Uncaria rhynchophylla and rhynchophylline improved kainic acid-induced epileptic seizures via IL-1β and brain-derived neurotrophic factor

Uncaria rhynchophylla (UR) has been used for the treatment of convulsions and epilepsy in traditional Chinese medicine. This study reported the major anti-convulsive signaling pathways and effective targets of UR and rhynchophylline (RP) using genomic and immunohistochemical studies. Epileptic seizure model was established by intraperitoneal injection of kainic acid (KA) in rats. Electroencephalogram and electromyogram recordings indicated that UR and RP improved KA-induced epileptic seizures. Toll-like receptor (TLR) and neurotrophin signaling pathways were regulated by UR in both cortex and hippocampus of KA-treated rats. KA upregulated the expression levels of interleukin-1β (IL-1β) and brain-derived neurotrophin factor (BDNF), which were involved in TLR and neurotrophin signaling pathways, respectively. However, UR and RP downregulated the KA-induced IL-1β and BDNF gene expressions. Our findings suggested that UR and RP exhibited anti-convulsive effects in KA-induced rats via the regulation of TLR and neurotrophin signaling pathways, and the subsequent inhibition of IL-1β and BDNF gene expressions.

The use of transcriptomics to unveil the role of nutrients in Mammalian liver

Liver is the organ primarily responding to diet, and it is crucial in determining plasma carbohydrate, protein, and lipid levels. In addition, it is mainly responsible for transformation of xenobiotics. For these reasons, it has been a target of transcriptomic analyses. In this review, we have covered the works dealing with the response of mammalian liver to different nutritional stimuli such as fasting/feeding, caloric restriction, dietary carbohydrate, cholesterol, fat, protein, bile acid, salt, vitamin, and oligoelement contents. Quality of fats or proteins has been equally addressed, and has the influence of minor dietary components. Other compounds, not purely nutritional as those represented by alcohol and food additives, have been included due to their relevance in processed food. The influence has been studied not only on mRNA but also on miRNA. The wide scope of the technology clearly reflects that any simple intervention has profound changes in many metabolic parameters and that there is a synergy in response when more compounds are included in the intervention. Standardized arrays to systematically test the same genes in all studies and analyzing data to establish patterns of response are required, particularly for RNA sequencing. Moreover, RNA is a valuable, easy-screening ally but always requires further confirmation.

Carthamus red from Carthamus tinctorius L. exerts antioxidant and hepatoprotective effect against CCl(4)-induced liver damage in rats via the Nrf2 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Carthamus red isolated from safflower (Carthamus tinctorius L., a Chinese traditional medicine) is evaluated for antioxidant and hepatoprotective activity.

MATERIALS AND METHODS

Carthamus red was isolated from a Na2CO3 extract of safflower and its analysis was carried out by HPLC/MS. Acute toxicity study was determined and the antioxidant activity was investigated using various established in vitro systems. An in vivo study against CCl4-induced liver injury was also conducted and compared with that of silymarin, a known hepatoprotective drug.

RESULTS

Carthamus red did not show any toxicity and mortality up to 2000mg/kg dose, and it showed strong antioxidant ability in vitro. In the in vivo study, carthamus red treatment lowered the serum levels of ALT, AST, ALP and total protein in liver damage rat models. Meanwhile, Nrf2, GSTα and NQO1 expressions were up-regulated at the protein level by carthamus red intervention. Additionally, the activities of antioxidant enzymes and level of GSH were elevated by carthamus red intervention, while the content of TBARS, which is an oxidative stress marker, was lessened. HE stain analysis showed that the condition of liver damage was mitigated.

CONCLUSION

This study demonstrates that carthamus red may serve as a candidate with strong a hepatoprotective effect and antioxidant activity in liver damage.

Antioxidant and hepatoprotective effects of silymarin phytosomes compared to milk thistle extract in CCl4 induced hepatotoxicity in rats

Milk thistle extract is a well-known hepatoprotectant with low bioavailability (20-50%). The objective of the present study is to prepare and characterize silymarin phytosomes and to test the hepatoprotective effect of the phytosomes in CCl4 induced liver injury in rats compared to milk thistle extract. Phytosomes were prepared using lecithin from soybeans and from egg yolk. The prepared phytosomes were examined using scanning electron microscopy, transmission electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy (H(1)NMR). The loading efficiency was >85% in all phytosomal formulations. Formula P2 (with the molar ratio of soybean lecithin to silybin 1:1) and P4 (with the molar ratio of egg-yolk lecithin to silybin 0.25:1) exhibited significantly (p < 0.05) faster release than milk thistle extract. The in vivo study revealed that phytosomes significantly (p < 0.05) decreased glutamic pyruvic transaminase and super oxide dismutase activities compared to milk thistle extract.