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

The milk thistle (Silybum marianum) compound Silibinin stimulates leukopoiesis from mouse embryonic stem cells

The milk thistle compound Silibinin (i.e., a 1:1 mixture of Silybin A and Silybin B) stimulates vasculogenesis of mouse embryonic stem (ES) cells. Because vasculogenesis and leukopoiesis are interrelated, the effect of Silibinin on leukopoiesis of ES cells was investigated. Treatment of differentiating ES cells with hydrosoluble Silibinin-C-2',3-dihydrogen succinate dose-dependent increased the number of CD18+ , CD45+ , and CD68+ cells, indicating leukocyte/macrophage differentiation. Silibinin treatment activated phosphoinositide 3-kinase (PI3K), AKT (protein kinase B), signal transducer and activator of transcription 3 (STAT3), stimulated hypoxia-induced factor-1α (HIF-1α), and vascular endothelial growth factor receptor 2 (VEGFR2) expression and raised intracellular nitric oxide (NO). Western blot experiments showed that upon coincubation with either the PI3K inhibitor LY294002, the STAT3 inhibitor Stattic, the AKT antagonist AKT inhibitor VIII, or the NO inhibitor L-NAME, the Silibinin-induced expression of CD18, CD45, and CD68 was abolished. Moreover, the stimulation of HIF-1α and VEGFR2 expression was blunted upon STAT3 and PI3K/AKT inhibition. Treatment of differentiating ES cells with L-NAME abolished the stimulation of VEGFR2 and VE-cadherin expression achieved with Silibinin, indicating that NO is involved in vasculogenesis and leukocyte differentiation pathways. In summary, the data of the present study demonstrate that Silibinin stimulates leukocyte differentiation of ES cells, which is associated to vasculogenesis and regulated by PI3K/AKT-, STAT3-, and NO-mediated signaling.

Antioxidant Supplementation in Renal Replacement Therapy Patients: Is There Evidence?

The disruption of balance between production of reactive oxygen species and antioxidant systems in favor of the oxidants is termed oxidative stress (OS). To counteract the damaging effects of prooxidant free radicals, all aerobic organisms have antioxidant defense mechanisms that are aimed at neutralizing the circulating oxidants and repair the resulting injuries. Antioxidants are either endogenous (the natural defense mechanisms produced by the human body) or exogenous, found in supplements and foods. OS is present at the early stages of chronic kidney disease, augments progressively with renal function deterioration, and is further exacerbated by renal replacement therapy. End-stage renal disease patients, on hemodialysis (HD) or peritoneal dialysis (PD), suffer from accelerated OS, which has been associated with increased risk for mortality and cardiovascular disease. During HD sessions, the bioincompatibility of dialyzers and dialysate trigger activation of white blood cells and formation of free radicals, while a significant loss of antioxidants is also present. In PD, the bioincompatibility of solutions, including high osmolality, elevated lactate levels, low pH, and accumulation of advanced glycation end-products trigger formation of prooxidants, while there is significant loss of vitamins in the ultrafiltrate. A number of exogenous antioxidants have been suggested to ameliorate OS in dialysis patients. Vitamins B, C, D, and E, coenzyme Q10, L-carnitine, a-lipoic acid, curcumin, green tea, flavonoids, polyphenols, omega-3 polyunsaturated fatty acids, statins, trace elements, and N-acetylcysteine have been studied as exogenous antioxidant supplements in both PD and HD patients.

In vivo antioxidant activity of mackerel (Scomber japonicus) muscle protein hydrolysate

Pacific chub mackerel (Scomber japonicus) is an important fish throughout the world, especially in East Asian countries, including Korea, China, and Japan. Protein hydrolysates from marine sources are commonly used as nutritional supplements, functional ingredients, and flavor enhancers in the food, beverage, and pharmaceutical industries. Antioxidants isolated from fish are relatively easy to prepare, are cost effective, and have no reported side effects. Hence, the present study aimed to investigate the in vivo antioxidant activities of mackerel muscle protein hydrolysate (MMPH) prepared using Protamex. The in vivo bioactivities of MMPH were investigated in alcoholic fatty liver mice (C57BL/6). Serum alanine aminotransferase and aspartate aminotransferase levels were comparable in test and control mice, whereas serum triglyceride and lipid peroxidation levels significantly (p < 0.05; p < 0.001) decreased after administration of MMPH (100-500 mg kg^-1), especially at a concentration of 100 mg kg^-1. A significant (p < 0.05) reduction in xanthine oxidase activity was observed in all groups treated with MMPH (100-500 mg kg^-1), as compared with the control group. Significantly (p < 0.05) higher superoxide dismutase (SOD) activity/protein expression and regulated catalase (CAT) activity/protein expression levels were observed in groups administered MMPH (100-500 mg kg^-1), especially at a concentration of 100 mg kg^-1. These results show that the abundant amino acids of S. japonicus play an important role in the cytosol of the liver cells by directly participating in the expression of xanthine oxidase and the detoxifying SOD and CAT proteins, thereby enhancing antioxidant ability and ultimately, inhibiting lipid peroxidation. This study demonstrated that muscle protein hydrolysate from S. japonicus has strong antioxidant activities.

The Milk Thistle (Silybum marianum) Compound Silibinin Inhibits Cardiomyogenesis of Embryonic Stem Cells by Interfering with Angiotensin II Signaling

The milk thistle (Silybum marianum (L.) Gaertn.) compound silibinin may be an inhibitor of the angiotensin II type 1 (AT₁) receptor which is expressed in differentiating embryonic stem (ES) cells and is involved in the regulation of cardiomyogenesis. In the present study, it was demonstrated that silibinin treatment decreased the number of spontaneously contracting cardiac foci and cardiac cell areas differentiated from ES cells as well as contraction frequency and frequency of calcium (Ca²⁺) spiking. In contrast, angiotensin II (Ang II) treatment stimulated cardiomyogenesis as well as contraction and Ca²⁺ spiking frequency, which were abolished in the presence of silibinin. Intracellular Ca²⁺ transients elicited by Ang II in rat smooth muscle cells were not impaired upon silibinin treatment, excluding the possibility that the compound acted on the AT₁ receptor. Ang II treatment activated extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH₂-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) pathways in embryoid bodies which were abolished upon silibinin pretreatment. In summary, our data suggest that silibinin inhibits cardiomyogenesis of ES cells by interfering with Ang II signaling downstream of the AT₁ receptor.

Therapeutic Potential of Plants and Plant Derived Phytochemicals against Acetaminophen-Induced Liver Injury

Acetaminophen (APAP), which is also known as paracetamol or N-acetyl-p-aminophenol is a safe and potent drug for fever, pain and inflammation when used at its normal therapeutic doses. It is available as over-the-counter drug and used by all the age groups. The overdose results in acute liver failure that often requires liver transplantation. Current clinical therapy for APAP-induced liver toxicity is the administration of N-acetyl-cysteine (NAC), a sulphydryl compound an approved drug which acts by replenishing cellular glutathione (GSH) stores in the liver. Over the past five decades, several studies indicate that the safety and efficacy of herbal extracts or plant derived compounds that are used either as monotherapy or as an adjunct therapy along with conventional medicines for hepatotoxicity have shown favorable responses. Phytochemicals mitigate necrotic cell death and protect against APAP-induced liver toxicityby restoring cellular antioxidant defense system, limiting oxidative stress and subsequently protecting mitochondrial dysfunction and inflammation. Recent experimental evidences indicat that these phytochemicals also regulate differential gene expression to modulate various cellular pathways that are implicated in cellular protection. Therefore, in this review, we highlight the role of the phytochemicals, which are shown to be efficacious in clinically relevant APAP-induced hepatotoxicity experimental models. In this review, we have made comprehensive attempt to delineate the molecular mechanism and the cellular targets that are modulated by the phytochemicals to mediate the cytoprotective effect against APAP-induced hepatotoxicity. In this review, we have also defined the challenges and scope of phytochemicals to be developed as drugs to target APAP-induced hepatotoxicity.

INTENSIFICATION OF PRODUCTION PROCESS OF THICK EXTRACT OF MILK THISTLE FRUITS BY ULTRASONIC PROCESSING OF RAW MATERIALS

The aim. This article is devoted to the intensification of the production process of a thick extract of milk thistle fruits using ultrasonic processing of raw materials.Materials and methods.As an object of the study, the crushed milk thistle fruitss from Penza “Biokor” company were used. As the extractant, an aqueous solution of ethanol 70% vol. was used. For ultrasonic processing of plant materials and extractant, the installation “Bandelin SONOPULS HD 3200” was used, the ultrasound frequency was 20 kHz, the radiator power was 280 W, and the temperature was 25°С. The concentration of the extract was performed using a rotary evaporator RV-10 at the temperature of 60°C and a vacuum of 600–650 Mmhg to a residual moisture content of 25%. Qualitative and quantitative analysis of the thick extract was carried out using spectrophotometry and chromatography. Quantitative analysis of the amount of flavolignans was performed on an SF-56 spectrophotometer. The separation of the flavolignan complex and the quantification of silibinin was performed on a liquid chromatograph “Agilent Technologies 1200 Infinity”.Results and discussion. During the study it was found out, that processing of the crushed milk thistle fruits by ultrasound at the soaking stage almost doubles the output of the flavoligan complex from medicinal plant materials. The maximum amount of flavolignans is extracted when the fruits of milk thistle and extractant are processed with ultrasound at the frequency of 20 kHz for 5 minutes. Thus the obtained thick extract of milk thistle fruits in the component composition contains both the target flavolignan complex (87.39%, silibinin – 24.36%), providing the hepatoprotective effect, and flavonoids – chlorogenic acid (1.69%) and dihydroquercetin (10.92%) exhibiting antioxidant activity. It was established that, according to the qualitative composition of flavolignans, the obtained thick extract corresponds to preparations based on milk thistle. Thus, for the first time, the method was proposed for obtaining a thick extract of milk thistle fruits using ultrasonic processing of raw materials and extractant at the soaking stage. The obtained thick extract is proposed to be used as an active pharmaceutical substance for the production of granules based on methionine and milk thistle flavolignans.Conclusion. The results of the experiments allow us to recommend obtaining a thick extract of the milk thistle fruits, using the stage of ultrasonic processing of raw materials and extractant for 5 minutes at the ultrasound frequency of 20 kHz.

The anti-inflammatory and anti-fibrotic effects of tadalafil in thioacetamide-induced liver fibrosis in rats

Liver fibrosis is a health concern that leads to organ failure mediated via production of inflammatory cytokines and fibrotic biomarkers. This study aimed to explore the protective effect of tadalafil, a phosphodiesterase-5 inhibitor, against thioacetamide (TAA)-induced liver fibrosis. Fibrosis was induced by administration of TAA (200 mg/kg, i.p.) twice weekly for 6 weeks. Serum transaminases activities, liver inflammatory cytokines, fibrotic biomarkers, and liver histopathology were assessed. TAA induced marked histopathological changes in liver tissues coupled with elevations in serum transaminases activities. Furthermore, hepatic content of nitric oxide and tumor necrosis factor-alpha, interleukin-6, and interleukin-1 beta were elevated, together with a reduction of interleukin-10 in the liver. In addition, TAA increased hepatic contents of transforming growth factor-beta, hydroxyproline, alpha-smooth muscle actin, and gene expression of collagen-1. Pretreatment with tadalafil protected against TAA-induced liver fibrosis, in a dose-dependent manner, as proved by the alleviation of inflammatory and fibrotic biomarkers. The effects of tadalafil were comparable with that of silymarin, a natural antioxidant, and could be assigned to its anti-inflammatory and anti-fibrotic properties.

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.

Sylimarin as hepatic protector and immunomodulator in Nile tilapia during Streptococcus agalactiae infection

This study investigated the use of silymarin, an extract obtained from the milk thistle (Silybum marianum) and its effects as a possible hepatoprotector in Nile tilapia (Oreochromis niloticus). Silymarin was used as feed additive to the diet at a concentration of 0.1% (1 kg per ton of dry ration) with the commercial product named Di-Heptarine S^® (16% silymarin phosphatide). A total of 90 juvenile tilapia with approximately 45 days old and mean weight of 0.72 ± 0.04 g were distributed in two groups, one fed with a diet with the hepatoprotector and the other without the additive. At the end of the assay (55 days after feeding), samples of blood were collected for hematological, immunological, histological (liver, spleen and intestine) and enzymatic analysis such as superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST). After 55 days all fish were challenged with Streptococcus agalactiae serotype Ib to verify the sylimarin effects on the immunological parameters and its protection effect while challenged. During the challenge period another biological material sample was collected for hematological, immunological and histopathological analysis (liver, spleen and intestine). Before the challenge, an increase on the count of thrombocyte was found in the supplemented fish. In the liver, dilation of the sinusoids was observed in unsupplemented fish while supplemented fish the alteration was less severe. No significant alteration was found in SOD, CAT and GST between the groups. Histological changes after the challenge were provoked by bacterial toxins as a result of inflammatory processes. Periacinar degeneration was less intense in unsupplemented fish when compared to supplemented fish. On the other hand, eosinophilic and lymphocytic infiltrate did occur in unsupplemented fish differently from supplemented fish which did not show the alteration. The survival was 28% higher in silymarin supplemented fish when compared to unsupplemented fish that presented no survival. Silymarin supplementation in the diet provided a hepatoprotective and immunomodulatory effect on Nile tilapia.

Silymarin Ameliorates Oxidative Stress and Enhances Antioxidant Defense System Capacity in Cadmium-Treated Mice

OBJECTIVE

Cadmium is an environmental pollutant which induces oxidative stress while silymarin as an antioxidant is able to scavenge free radicals. The aim of the present study was to investigate the effect of silymarin on oxidative stress markers and antioxidant defense system capacity in mice treated with cadmium chloride.

MATERIALS AND METHODS

In this experimental study, adult mice were divided into four groups as follow: i. Control, ii. Cadmium chloride (5 mg/kg b.w., s.c.), iii. Silymarin+cadmium chloride, and iv. Silymarin (100 mg/kg b.w., i.p.). Mice were treated with cadmium chloride for 24 hours and silymarin was administered 24 hours before the cadmium. Blood samples were then collected from the experimental groups and their sera were prepared. To investigate oxidative stress markers in the serum, the amount of malondialdehyde (MDA) and thiol groups (-SH) were evaluated. To measure the total antioxidant power in the serum, Ferric Reducing/ Antioxidant Power (FRAP) method was used. In addition, the activity of enzymes including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) was assessed to evaluate serum antioxidant defense power.

RESULTS

In the cadmium-treated group, the amount of MDA significantly increased as compared to the control group. In silymarin+cadmium group, silymarin significantly ameliorated the level of MDA compared to the cadmium group. In addition, cadmium significantly reduced serum FRAP, the activity of antioxidant defense system enzymes and thiol groups compared to the control. In silymarin+cadmium group, silymarin could significantly reverse the reduction of these markers compared to the cadmium group. Administration of silymarin alone caused a significant increase in serum FRAP, the activity of antioxidant defense system enzymes and thiol groups compared to the control group.

CONCLUSION

Silymarin as a powerful antioxidant reverses the toxic effect of cadmium on the serum levels of lipid peroxidation, total antioxidant power, antioxidant defense system enzymes activity and thiol groups.

Formulation and Evaluation of Silymarin-Loaded Chitosan-Montmorilloite Microbeads for the Potential Treatment of Gastric Ulcers

Silymarin-loaded mucoadhesive microbeads of Chitosan-MMT were developed using the ionotropic gelation technique. Characterization of the microbeads was performed by DSC, XRD, SEM, and FTIR techniques. In vitro mucoadhesion and drug release studies; gastroprotective studies including the measurement of ulcerative index; the determination of gastric wall mucus; and the determination of percentage protection, biochemical, and histopathological studies were also performed. Microbeads batches were evaluated for particle size (120⁻140 µm), actual drug content, (49.36⁻58.18%) and entrapment efficiency (72.52⁻92.39%).Biochemical estimation of myeloperoxidase was found to be 0.10⁻0.75 µmoles/g/tissue. Significant reduction in the ulcerative index showed the gastroprotective effect of the formulation. Silymarin-loaded beads of Chitosan-MMT were found to exhibit good mucoadhesion and efficient release of the drug, and were found to be a promising drug carrier system for the treatment of gastric ulcers.

Nutraceutical Approach to Non-Alcoholic Fatty Liver Disease (NAFLD): The Available Clinical Evidence

Non-alcoholic fatty liver disease (NAFLD) is a clinical condition characterized by lipid infiltration of the liver, highly prevalent in the general population affecting 25% of adults, with a doubled prevalence in diabetic and obese patients. Almost 1/3 of NAFLD evolves in Non-Alcoholic SteatoHepatitis (NASH), and this can lead to fibrosis and cirrhosis of the liver. However, the main causes of mortality of patients with NAFLD are cardiovascular diseases. At present, there are no specific drugs approved on the market for the treatment of NAFLD, and the treatment is essentially based on optimization of lifestyle. However, some nutraceuticals could contribute to the improvement of lipid infiltration of the liver and of the related anthropometric, haemodynamic, and/or biochemical parameters. The aim of this paper is to review the available clinical data on the effect of nutraceuticals on NAFLD and NAFLD-related parameters. Relatively few nutraceutical molecules have been adequately studied for their effects on NAFLD. Among these, we have analysed in detail the effects of silymarin, vitamin E, vitamin D, polyunsaturated fatty acids of the omega-3 series, astaxanthin, coenzyme Q10, berberine, curcumin, resveratrol, extracts of Salvia milthiorriza, and probiotics. In conclusion, Silymarin, vitamin E and vitamin D, polyunsaturated fatty acids of the omega-3 series, coenzyme Q10, berberine and curcumin, if well dosed and administered for medium–long periods, and associated to lifestyle changes, could exert positive effects on NAFLD and NAFLD-related parameters.

Silymarin nanoformulation as potential anticancer agent in experimental Ehrlich ascites carcinoma-bearing animals

Aim: This study aimed to evaluate, for the first time the potential use of a safe biocompatible nanoformulation of silymarin (SM) as antitumor agent and to provide its mechanism of action compared with native SM. Materials & methods: SM was loaded into pluronic nanomicelles and Ehrlich ascites carcinoma-tumor-bearing mice were used as experimental model. Biochemical parameters including SOD, CAT and GSH, lipid peroxidation biomarkers (MDA), histopathological, ultrastructural and immunohistochemical studies were applied on the Ehrlich ascites carcinoma cells. Furthermore, the cell cycle as well as caspase-3 were examined. Results & conclusion: Nanoformulated SM (SMnp) destroyed tumors via increasing SOD, CAT and GSH concomitant with decreasing MDA. Moreover, SMnp-induced apoptosis through decreasing Ki-67 and Bcl2 expression, along with the activation of caspase-3, leads to inhibition of proliferation and the arrest of ceel cycle progression at the G1/S phase. Electron microscopy studies presented the superiority of SMnp over native SM in causing mitochondrial and nuclear degeneration in cancer cells.

A comparison of the effects of thymoquinone, silymarin and N-acetylcysteine in an experimental hepatotoxicity

This study investigated the effects of thymoquinone, silymarin, and N-acetylcysteine in a rat model with carbon tetrachloride (CCl₄)-induced hepatotoxicity. Although numerous similar studies are available, we aimed to compare the efficacy of these agents by considering N-acetylcysteine as a reference compound. A total of 50 male Wistar albino rats were randomly designated as 5 groups: Group I, CCl₄; group II, thymoquinone and CCl₄; group III, silymarin and CCl₄; group IV, N-acetylcysteine and CCl₄; group V, control group. CCl₄ was administered intraperitoneally at a dose of 1.5 mL/kg (a mixture of CCl₄: olive oil, 1:2) twice a week. Thymoquinone was administered at a dose of 10 mg/kg, silymarin was administered at a dose of 100 mg/kg, and N-acetylcysteine was administered at a dose of 100 mg/kg by daily intraperitoneal injection. At the end of four weeks, blood and liver tests were analyzed. The results were evaluated statistically via the one-way ANOVA test. A p-value <0.05 was considered statistically significant. Thymoquinone, silymarin, and N-acetylcysteine improved the levels of alanine aminotransferase, tumor necrosis factor-α, platelet-derived growth factor-BB, and interleukin-6, which were increased by CCl₄. Thymoquinone and silymarin showed the positive increase in liver glutathione levels. Thymoquinone, silymarin, and N-acetylcysteine improved blood total oxidant status. In the histological examinations of liver tissue, thymoquinone decreased necrosis, and inflammation. The most positive decrease in the α-smooth muscle actin-stained hepatic stellate cell count was only observed with thymoquinone. These findings suggest that thymoquinone, silymarin, and N-acetylcysteine have potential for the treatment of diseases causing liver injury. Among these agents, thymoquinone showed the best results on most of the parameters. Since TQ appears to be at least as effective as SM and NAC in our in-vitro study, we propose that it is time for clinical studies with thymoquinone on hepatotoxicity.

Performance and serum biochemical profile of Japanese quail supplemented with silymarin and contaminated with aflatoxin B1

The aim of this study was to evaluate the hepatoprotective effect of silymarin in diets contaminated or not with aflatoxin B1 (AFB1) on the productive performance and serum biochemical profile of Japanese quail (Coturnix coturnix japonica) in the laying phase. A total of 240 12-week-old Japanese quail was used in a completely randomized design in a 3 × 2 factorial scheme (additives x contaminated or not with AFB1 - 1,500 μg/kg), totaling 6 treatments and 5 replicates of 8 birds each. The additives used were silymarin (500 g/ton), adsorbent (1 kg/ton), and a control diet (without additive). Of the total aflatoxin content, 84.64% was AFB1; 4.28% was AFB2; 11.07% was AFG1; and AFG2 was not detected. The data were submitted to ANOVA, and means were compared by Tukey's test. There was no interaction (P > 0.05) between the additive and AFB1 on performance parameters. However, the inclusion of AF in diets reduced (P < 0.05) egg weight and feed intake, impairing feed conversion compared to the unchallenged groups. There was an increase (P < 0.05) in blood concentrations of aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), and creatine kinase (CK) in birds challenged with AFB1, regardless of the additive used, characterizing a possible alteration in hepatic metabolism. Serum total protein and globulin levels were reduced (P < 0.05) in birds challenged with toxins. The consumption of diets contaminated with 1,500 μg AFB1/kg altered hepatic function in quail, impairing productive performance and egg weight. The concentrations of silymarin and adsorbent evaluated in this study were not able to mitigate the negative effect of toxins on the metabolism and performance of laying quail.

Silibinin protects human endothelial cells from high glucose-induced injury by enhancing autophagic response

Silibin, a flavonoid from the seeds of Silybum marianum (L.) Gaertn. (Asteraceae) has been reported to produce curative properties in diabetes. Autophagy is generated by a vast array of insults for removal of damaged proteins and organelles from the cell. Inadequate autophagy promotes endothelial cells dysfunction and delays in diabetic ulcers recovery. We hypothesized that silibinin could protect endothelial cells against high glucose-induced damage by engaging autophagic responses. HUVECs viability was evaluated by MTT assay. The Griess method and TBARS assay were used to monitor changes in the levels of nitric oxide and malondialdehyde, respectively. ROS generation was recorded in DCFDA-stained cells analyzed by flow cytometry. To investigate the role of silibinin on migration, we used scratch test. The level of autophagy proteins LC3, Becline-1, and P62 were measured by Western blotting. Our data showed that silibinin had potential to increase cell survival after exposure to high glucose condition. Total levels of oxidative stress markers were profoundly reduced and the activity of GSH was increased by silibinin. High glucose suppressed HUVECs migration to the scratched area. However, a significant increase in cell migration was observed after exposure to silibinin. Autophagy was blocked at the late stage by high glucose concentration and silibinin initiated an autophagic response by reducing P62 and enhancing Beclin-1 and LC3-II-LC3-I ratio. These effects were blocked by autophagy inhibitor of 3-Methyladenine. These observations suggest that silibinin could protect HUVECs from high glucose induced-damage possibly by activation of autophagy pathway.

Anti-inflammatory effects and anti-oxidant capacity of Myrathius arboreus (Cecropiaceae) in experimental models

BACKGROUND

Inflammation is involved in various diseases; search for safe treatments is warranted. Anti-inflammatory effects of ethanol extract of Myrathius arboreus (EEMa) were studied in carrageenan-induced model, formaldehyde sub-acute-induced model, and in 48 h lipopolysaccharide-induced air pouch model of inflammation. EEMa membrane-stabilizing activities and anti-oxidant capacity were determined in vitro.

METHODS

In the carrageenan model EEMa (125, 250, or 500 mg/kg), indomethacin (5 mg/kg), or vehicle 3 mL/kg was administered orally in rats (n=5). After 1 h, 0.1 mL of 1% carrageenan was injected into the right hind paw of rats. Change in edema sizes was measured for 3 h with plethysmometer. One-tenth milliliter (0.1 mL) of 2.5% formaldehyde was injected into the rat paw on the first day and the third day to induce sub-acute inflammation; changes in the edema sizes were determined, and percentages of inhibitions were calculated. Anti-inflammatory effects of EEMa were further examined in lipopolysaccharide (LPS)-induced air-pouch based on leukocytes count, volume of exudates, levels of malondialdehyde, glutathione, superoxide dismutase, nitric oxides, and tumor necrosis factor released into the inflammatory fluids. EEMa-free radicals scavenging activities were studied in DPPH and reducing power tests. Membrane-stabilizing activities of EEMa were evaluated in the red blood cell lysis induced by thermal and hypotonic solution.

RESULTS

EEMa (250, 500 mg/kg) produced significant (p<0.001; p<0.05) inhibition of inflammation when compared with vehicle. Also, EEMa (250, 500, or 1000 μg/mL) significantly stabilized membrane and produced free radical scavenging activities.

CONCLUSIONS

M. arboreus possesses anti-inflammatory and the anti-oxidant properties that might benefit translational medicine.

Betaine and ascorbic acid modulate indoor behavior and some performance indicators of broiler chickens in response to hot-dry season

Heat stress causes lipid peroxidation in poultry, necessitating antioxidant administration. The experiment evaluated the modulating effects of betaine and ascorbic acid (AA) on indoor behavior and some performance parameters of broiler chickens during the hot-dry season. Experimental groups were: Group I (control) was daily given sterile water; Group II, betaine at 250 mg/kg; Group III, AA (50 mg/kg), and Group IV, betaine (250 mg/kg) + AA (50 mg/kg), orally for 42 days. The natural occurring dry-bulb temperature (28.0-37.0 °C), relative humidity (69.0-93.0%), and temperature-humidity index (27.9-36.1 °C) were predominantly outside the thermo-neutral zone for broiler chickens, indicating heat stress conditions. Scan test, used to assess the percentage of birds sitting/lying, panting, feeding, drinking and spreading wings, was performed at 06:00 h, 13:00 h and 18:00 h on each of days 35 and 42. Feed intakes (FD), water consumption (WC), body weight, average daily weight gain (ADG) and feed-to-gain ratio (FGR) were obtained. Betaine+AA reduced (P < 0.05) percentage of birds panting; AA decreased (P < 0.05) percentage of birds spreading wing, compared with control. Finisher phase: betaine and/or AA, decreased FGR, increased ADG (P < 0.05); betaine reduced (P < 0.01) FD compared with control. Grower phase: betaine, either alone or with AA, lowered FGR and FD (P < 0.01); AA reduced (P < 0.01) FD, compared with control. Starter phase: betaine and/or AA decreased WC (P < 0.05); AA lowered FGR, compared with controls. Betaine administration decreased (P < 0.05) FD at 4 week-old, but its administration, either alone or with AA, reduced WC at 1 week-old, compared with control. Overall, betaine and/or AA group lowered FGR compared with controls. In conclusion, administration of betaine and/or AA to broiler chickens modulated indoor behavior, some performance indicators and water consumption during the hot-dry season.

RAGE-dependent mitochondria pathway: a novel target of silibinin against apoptosis of osteoblastic cells induced by advanced glycation end products

Advanced glycation end products (AGEs) can stimulate osteoblast apoptosis and have a critical role in the pathophysiology of diabetic osteoporosis. Mitochondrial abnormalities are closely related to osteoblast dysfunction. However, it remains unclear whether mitochondrial abnormalities are involved in AGE-induced osteoblastic cell apoptosis. Silibinin, a major flavonolignan compound of silimarin, has strong antioxidant and mitochondria-protective properties. In the present study, we explored the possible mitochondrial mechanisms underlying AGE-induced apoptosis of osteoblastic cells and the effect of silibinin on osteoblastic cell apoptosis. We demonstrated that mitochondrial abnormalities largely contributed to AGE-induced apoptosis of osteoblastic cells, as evidenced by enhanced mitochondrial oxidative stress, conspicuous reduction in mitochondrial membrane potential and adenosine triphosphate production, abnormal mitochondrial morphology, and altered mitochondrial dynamics. These AGE-induced mitochondrial abnormalities were mainly mediated by the receptor of AGEs (RAGE). In addition, we found that silibinin directly downregulated the expression of RAGE and modulated RAGE-mediated mitochondrial pathways, thereby preventing AGE-induced apoptosis of osteoblastic cells. This study not only provides a new insight into the mitochondrial mechanisms underlying AGE-induced osteoblastic cell apoptosis, but also lays a foundation for the clinical use of silibinin for the prevention or treatment of diabetic osteoporosis.

Silibinin Improves TNF-α and M30 Expression and Histological Parameters in Rat Kidneys After Hepatic Ischemia/Reperfusion

BACKGROUND

Remote kidney damage is a sequel of hepatic ischemia-reperfusion (I/R) injury. Silibinin is the main ingredient of the milk thistle plant seed extract with known antioxidant and hepatoprotective activity. Our study investigates the nephroprotective potential of intravenously administered silibinin, as a lyophilized SLB-hydoxypropyl-beta-cyclodextrin product, in hepatic I/R injury.

MATERIAL AND METHODS

63 Wistar rats were divided into three groups: Sham (virtual intervention); Control (45 min ischemia and reperfusion); and Silibinin (200 μL intravenous silibinin administration after 45 min of ischemia). Kidney tissues were collected to determine TNF-α, M30 and histopathological changes at predetermined time intervals.

RESULTS

Comparing Sham vs. Control groups, proved that hepatic I/R injury increased renal TNF-α and M30 expression. Deterioration was observed in hyperemia/filtration of renal parenchyma and tubules, cortical filtration, tubular necrosis and edema (tissue swelling index). Intravenous silibinin administration and comparison of the Control vs. Silibinin groups showed a statistically significant decrease in TNF-α levels at 240 min following I/R (p < 0.0001), and in M30 at 180 min (p = 0.03) and 240 min (p < 0.0001). Renal parameters have significantly decreased in: hyperemia/filtration of renal parenchyma at 120 min (p = 0.003), 180 min (p = 0.0001) and 240 min (p = 0.0002); hyperemia/filtration of renal tubules at 120 min (p = 0.02), 180 min (p = 0.0001) and 240 min (p = 0.0005); cortical filtration (240 min - p = 0.005); tubular necrosis (240 min - p = 0.021); and edema (240 min - p = 0.001).

CONCLUSION

Our study confirms that hepatic I/R injury causes remote renal damage while the intravenous administration of silibinin leads to statistically significant nephroprotective action.

Differential accumulation of silymarin induced by exposure of Silybum marianum L. callus cultures to several spectres of monochromatic lights

Silybum marianum L. (Milk thistle) is one of the most extensively studied medicinal herbs with well-known hepatoprotective activity. Light is considered as a key abiotic elicitor influencing several physiological processes in plants, including the biosynthesis of secondary metabolites. In this study, we investigated the influence of light quality on morphological and biochemical aspects in in vitro grown leaf-derived callus cultures of S. marianum. Combination of 6-benzylaminopurine (BAP 2.5 mg/L) and α-naphthalene acetic acid (NAA 1.0 mg/L) resulted in optimum callogenic response (97%) when placed under cool-white light with 16 h light and 8 h dark. Red light significantly increased the total phenolic content (TPC), total flavonoid content (TFC), antioxidant and superoxide dismutase (SOD) activities while highest peroxidase (POD) activity was recorded for the dark grown cultures, followed by green light grown cultures. HPLC analysis revealed enhanced total silymarin content under red light (18.67 mg/g DW), which was almost double than control (9.17 mg/g DW). Individually, the level of silychristin, isosilychristin, silydianin, silybin A and silybin B were found greatest under red light, whereas green spectrum resulted in highest accumulation of isosilybin A and isosilybin B. Conversely, the amount of taxifolin was found maximum under continuous white light (0.480 mg/g DW) which was almost 8-fold greater than control (0.063 mg/g DW). A positive correlation was found between the TPC, TFC and antioxidant activities. This study will assist in comprehending the influence of light quality on production of valuable secondary metabolites in in vitro cultures of S. marianum L.

Discovery of C-3 Tethered 2-oxo-benzo[1,4]oxazines as Potent Antioxidants: Bio-Inspired Based Design, Synthesis, Biological Evaluation, Cytotoxic, and in Silico Molecular Docking Studies

The discovery of C-3 tethered 2-oxo-benzo[1,4]oxazines as potent antioxidants is disclosed. All the analogs 20a-20ab have been synthesized via “on water” ultrasound-assisted irradiation conditions in excellent yields (upto 98%). All the compounds have been evaluated for their in vitro antioxidant activities using DPPH free radical scavenging assay as well as FRAP assay. The result showed promising antioxidant activities having IC₅₀ values in the range of 4.74 ± 0.08 to 92.20 ± 1.54 μg/mL taking ascorbic acid (IC₅₀ = 4.57 μg/mL) as standard reference. In this study, compounds 20b and 20t, the most active compound of the series, showed IC₅₀ values of 6.89 ± 0.07 μg/mL and 4.74 ± 0.08 μg/mL, respectively in comparison with ascorbic acid. In addition, the detailed SAR study shows that electron-withdrawing group increases antioxidant activity and vice versa. Furthermore, in the FRAP assay, eight compounds (20c, 20j, 20m, 20n, 20r, 20u, 20z, and 20aa) were found more potent than standard reference BHT (C_0.5FRAP = 546.0 ± 13.6 μM). The preliminary cytotoxic study reveals the non-toxic nature of active compounds 20b and 20t in non-cancerous 3T₃ fibroblast cell lines in MTT assay up to 250 μg/mL concentration. The results were validated via carrying out in silico molecular docking studies of promising compounds 20a, 20b, and 20t in comparison with standard reference. To the best of our knowledge, this is the first detailed study of C-3 tethered 2-oxo-benzo[1,4]oxazines as potential antioxidant agents.

Protective Effects of Silymarin Against Age-Related Hearing Loss in an Aging Rat Model

Age-related hearing loss (ARHL) is one of the most common chronic degenerative disorders. Several studies have indicated that supplementation with some antioxidants can slow down the progression of ARHL. Despite several lines of evidence about the potent antioxidant and anti-aging effects of silymarin, its protective effect against ARHL has not evaluated yet. The aim of the current study was to investigate the effects of silymarin in prevention of ARHL in a d-Galactose-induced aging rat model for the first time. 45 male wistar rats aged 3-month old were divided into 5 groups: group 1, 2 and 3 received 500 mg/kg/day d-Gal plus 100, 200 and 300 mg/kg/day silymarin respectively for 8 weeks, placebo group received 500 mg/kg/day d-Gal plus propylene glycol as placebo, and control group received normal saline during this period of time. Auditory brainstem responses were measured at several frequencies (4, 6, 8, 12 and 16 kHz) before and after the intervention. Placebo group and group 3 showed significant ABR threshold increase across frequencies of 4, 6, 16 kHz compared with the other groups (P < 0.05). However, rats treated with silymarin 100 and 200 mg/kg/day plus d-Gal did not show any significant ABR threshold shifts. Similarly, ABR amplitude of P2 at 4, 8 kHz and P1, P4 at 4 kHz in the placebo group and group 3 were decreased significantly compared with other groups (P < 0.05). However, no significant differences are found in ABR absolute and inter-peak latencies between groups (P > 0.05). The findings indicates that silymarin with doses of 100 and 200 mg/kg/day has protective effect against ARHL and it can be supplemented into the diet of older people to slow down the progression of age-related hearing loss.

Silymarin ameliorates expression of urotensin II (U-II) and its receptor (UTR) and attenuates toxic oxidative stress in the heart of rats with type 2 diabetes

Type 2 diabetes mellitus (T2DM) is associated with an increased risk of cardiovascular disease (CVD). Urotensin II ((U-II)) and its receptor (UTR) are involved in the progression of CVD through enhancement in the production of reactive oxygen species (ROS). Since silymarin (SMN) is a natural agent with anti-diabetic effects, this study aimed to investigate the antioxidant potency of SMN on the expression of (U-II)/UTR system and oxidative stress status in the heart of type 2 diabetic rats. Thirty-six male Wistar rats were randomly divided into six groups (n = 6). Control and diabetic groups treated with or without SMN (60 and 120 mg/kg/day) for 2 months. Fasting blood sugar (FBS), insulin, lipid profile, creatine kinase-MB ((CK-MB)), lactate dehydrogenase (LDH) and markers of oxidative stress were measured by spectrophotometric methods while (U-II) and UTR gene expression was determined by qPCR method. SMN significantly reduced the FBS level, increased the concentration of insulin and improved HOMA-IR. SMN prevented diabetes-induced weight loss, and attenuated the increased levels of total oxidative status (TOS), malondialdehyde (MDA), and nitric oxide (NO). Diabetes-induced reduction of total thiol molecules content (TTM) was normalized to the normal level in SMN treated rats. SMN significantly modulated serum lipid profile, reduced the expression of (U-II) and UTR in the heart, and improved histopathological changes in the heart tissues. Therefore, the current study indicated that SMN ameliorated unpleasant diabetic characteristics via down-regulation of (U-II) and UTR gene expression and modulation of oxidative stress in the heart tissue of type 2 diabetic rats.

Phytochemical analysis, molecular docking and antiamnesic effects of methanolic extract of Silybum marianum (L.) Gaertn seeds in scopolamine induced memory impairment in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Silybum marianum (L.) Gaertn and its main component silymarin have been extensively studied and have been found effective in various neurological disorders.

AIMS OF THE STUDY

The aim of the current study is to identify phytoconstituents in the methanolic extract (Me. Ext) of Silybum marianum (L.) Gaertn seeds and to study in-vivo the anti-amnesic effects along with in vitro antioxidant and acetylcholinesterase (AChE) and buteryl cholinesterase (BChE) inhibition potential. Induced fir docking (IFD) results have confirmed that quercetin, morin and rutin showed good affinity when docked into AChE binding site.

MATERIALS AND METHODS

The present study investigates the in-vitro AChE and BChE inhibition potential of the Me-Ext of Silybum marianum (L.) Gaertn at various concentrations (31.25, 62.50, 125, 250, 500, 1000µg/mL) using Ellman's spectrophotometric analysis, while antioxidant potential against DPPH and ABTS were determined using Brand-Williams spectrophotometric method. Furthermore, the in-vivo anti-amnesic effects of Me. Ext at the dose level of 50, 100 and 200mg/kg were also evaluated using scopolamine -induced memory impairment in mice in the novel object recognition test (NORT) and Y-maze test.

RESULTS

The Me. Ext showed a concentration dependent inhibition of AChE and BChE with IC50 values of 110 and 130µg/mL respectively and antioxidant activity against DPPH and ABTS with IC50 values 280 and 220µg/mL, respectively. In mice, Me. Ext reversed the amnesia induced by scopolamine as indicated by a dose-dependent increase in spontaneous alternation performance in the Y-maze task (p< 0.05 versus scopolamine) and increase in the discrimination index in the NORT comparable to the standard drug donepezil 2mg/kg. HPLC-UV analysis showed the presence of quercetin, rutin and morin. Induced fit docking (IFD) was performed using quercetin, rutin and morin, Glide Gscore and IFD score of all compounds were consistent with their experimental AChE inhibitory activities.

CONCLUSION

The results indicate that Silybum marianum (L.) Gaertn could be a new source for the isolation of phytoconstituents useful in cognition and memory disorders such as Alzheimer's disease.

Protective effects of silymarin on triptolide-induced acute hepatotoxicity in rats

Silymarin has been used in the treatment of a number of liver diseases for a long time, but its efficacy in preventing triptolide induced acute hepatotoxicity has not been reported previously. The present study aimed to assess the protective effect of silymarin against triptolide (TP)-induced hepatotoxicity in rats. Rats were orally administrated with silymarin (50, 100 and 200 mg/kg) for 7 days and received intraperitoneal TP (2 mg/kg) on the day 8. Hepatic injuries were comprehensively evaluated in terms of serum parameters, morphological changes, oxidative damage, inflammation and apoptosis. The results demonstrated that TP-induced increases in serum parameters, including alanine transaminase, aspartate aminotransferase, alkaline phosphatase, total cholesterol and γ-glutamyl transpeptidase, which were determined using a biochemical analyzer, and histopathological alterations and hepatocyte apoptosis as determined by hematoxylin and eosin and TUNEL staining, respectively, were prevented by silymarin pretreatment in a dose-dependent manner. TP-induced depletions in the activity of the antioxidant enzymes superoxide dismutase, glutathione peroxidase, glutathione S-transferase and catalase, and glutathione levels, were also significantly reversed by silymarin, as determined using specific kits. Additionally, silymarin dose-dependently exhibited inhibitory effects on malonaldehyde content in the liver. The production of proinflammatory cytokines was investigated using ELISA kits, and the results demonstrated that silymarin dose-dependently inhibited the production of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10 and IL-1β in the liver. To determine the mechanism of silymarin, western blot analysis was performed to investigate the protein expression of phosphorylated (p)-p38 and p-c-Jun N-terminal kinase (JNK) of the TNF-α induced inflammatory response and apoptotic pathways. Silymarin significantly blocked p38 and JNK phosphorylation and activation. Additionally, the expression of the proapoptotic proteins cytochrome c, cleaved caspase-3 and Bcl-2-associated X was also reduced following treatment with silymarin, as determined by ELISA, western blotting and immunohistochemistry, respectively. In conclusion, silymarin was demonstrated to dose-dependently protect rat liver from TP-induced acute hepatotoxicity, with the high dose (200 mg/kg) achieving a superior effect. This protective effect may be associated with the improvement of antioxidant and anti-inflammatory status, as well as the prevention of hepatocyte apoptosis. Therefore, silymarin may have the potential to be applied clinically to prevent TP-induced acute hepatotoxicity.

Radioprotective effects of Silymarin on the sperm parameters of NMRI mice irradiated with γ-rays

Free radicals and reactive oxygen species (ROS) are generated using various endogenous systems or from external sources such as exposure to different physiochemicals. Ionizing radiation damage to the cell can be caused by the direct or indirect effects of radiotherapy processes. Silymarin (SM), a flavanolignan compound, has been identified as a natural potent antioxidant with cytoprotection activities due to scavenging free radicals. The aim of the present study was to evaluate the radioprotective effect of SM on sperm parameters of mice induced by γ-rays. A total number of 40 adult, male NMRI mice were randomly divided into four equal groups. The control group was neither treated with SM nor irradiated by γ-rays. The second group was only irradiated with 2Gy of γ-rays. The third group was firstly treated with 50mg/kg of SM for 7 consecutive days, and one day later, last injections were irradiated by 2Gy of γ-rays. The fourth groups received only 50mg/kg of SM for 7 consecutive days. All the animals were treated intraperitoneally. Histopathological and morphometrical examinations were performed. The data were analyzed using ANOVA and Tukey post hoc test. A value of p<0.05 was considered significant. The results showed that in the radiation-only group when compared with those treated with SM and irradiated, a significant different was observed in testicular parameters and DNA damage (p<0.05). In conclusion, SM can be considered as a promising herbal radioprotective agent in complementary medicine which may play an important role to protect normal spermatocytes against possible effects of γ-radiation-induced cellular damage.

Esomeprazole ameliorates CCl4 induced liver fibrosis in rats via modulating oxidative stress, inflammatory, fibrogenic and apoptotic markers

BACKGROUND

Hepatic fibrosis is a major health problem that requires further medical attention. Proton pump inhibitors are proven to possess other therapeutic potentials apart of their acid anti-secretory actions.

AIM OF THE WORK

To test possible anti-fibrotic effect of esomeprazole magnesium trihydrate in management of liver fibrosis compared to silymarin, the well-known hepatoprotective agent.

MATERIALS & METHODS

40 male albino rats were divided into 4 groups: normal control group; CCl₄-treated group (1 mL/kg 40% CCl₄, diluted in olive oil) I.P twice weekly for 6 weeks; esomeprazole-treated group (30 mg/kg body weight); and Silymarin-treated group (100 mg/kg body weight). Both esomeprazole and silymarin were given orally daily for two weeks after the last CCl₄ dose. Serum and tissue samples were assessed for histopathological and biochemical analyses.

RESULTS

Esomeprazole reversed hepatocellular damage, improved liver integrity, corrected major histopathological disturbances induced by CCl₄ and lowered fibrosis scoring. It also improved anti-oxidant capacity and attenuated lipid peroxidation. Esomeprazole treatment resulted in down-regulation of hepatic pro-apoptotic Bax and up-regulation of anti-apoptotic Bcl2 protein expressions. In addition, it resulted in inhibition of TNF-α, TGF-β and IL-6 -mediated inflammatory responses, and retrieval of the epithelial marker e-cadherin.

CONCLUSION

Esomeprazole confers significant anti-fibrotic actions. Further study is needed to elucidate other probable mechanisms for this effect and to test their anti-fibrotic potential clinically.

Clinical characteristics and outcome of toxicity from Amanita mushroom poisoning

Objective

To describe and analyze the clinical characteristics and outcome of amatoxin poisoning cases.

Methods

We performed a retrospective cohort study of amatoxin poisoning cases from Ramathibodi Poison Center Toxic Exposure Surveillance System, from May 2013 to August 2015.

Results

There were 30 consultations with a total of 55 poisoning cases. Most cases were male and from the north-east region. Hepatitis, acute kidney injury, jaundice, and coagulopathy accounted for 74%, 46.3%, 44.7%, and 52.8% of the cases, respectively. Almost all of the patients were admitted to the hospital, and the median duration of hospital stay was found to be 4 days. Mortality rate was found to be 27.3%. Most patients (73%) received the treatment including multiple-dose activated charcoal (67.5%), intravenous N-acetylcysteine (87.5%), and benzylpenicillin (45%). In 60% of the cases, the treatment was initiated within 24 h after eating mushrooms. Exchange transfusion and liver transplantation were performed in one severe case. However, this patient died eventually. Because intravenous silybinin is not available in Thailand during the study period, 8 patients received oral silymarin instead. All 8 patients had hepatitis and were treated with high dosage of oral silymarin (5 patients with 4.48 g/day, 2 patients with 1.68 g/day, and 1 patient with 1.4 g/day) for a couple of days. One of these patients died as she received treatment very late; she was treated with silymarin at 1.68 g/day dosage. Thus, the fatality in oral silymarin treatment group was 12.5%. We performed the analysis between the dead and survival groups. We found that in hepatitis, initial and maximum serum aspartate transaminase, initial and maximum serum alanine transaminase, and acute kidney injury were significantly different between the two groups.

Conclusion

Amanita mushroom poisoning caused high fatalities. Serum transaminase and creatinine were the factors associated with death. Treatment with oral high dose silymarin should be investigated further as one of the principal therapies in amatoxin poisoning.

Hepatoprotective properties of Penthorum chinense Pursh against carbon tetrachloride-induced acute liver injury in mice

Background

Penthorum chinense Pursh (Penthoraceae, PCP), a well-known Miao ethnomedicine, has been traditionally used to treat several liver-related diseases, such as jaundice and viral hepatitis. The aims of the present study were to evaluate the probable properties of the aqueous extract of PCP on carbon tetrachloride (CCl₄)—induced acute liver injury in mice.

Methods

C57BL/6 mice were orally administered an aqueous extract of PCP (5.15 and 10.3 g/kg BW) or silymarin (100 mg/kg) once daily for 1 week prior to CCl₄ exposure. Silymarin serves as a positive drug to validate the effectivenes of PCP.

Results

A single dose of CCl₄ exposure caused severe acute liver injury in mice, as evidenced by the elevated serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alanine phosphatase (ALP), and the increased TUNEL-positive cells in liver, which were remarkably ameliorated by the pretreatment of PCP. PCP was also found to decrease the levels of malondialdehyde (MDA), restore the glutathione (GSH) and enhance the activities of superoxide dismutase (SOD) and catalase (CAT) in the liver. In addition, the pretreatment of PCP inhibited the degradation of hepatic cytochrome P450 2E1 (CYP2E1), up-regulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its target proteins in CCl₄-treated mice.

Conclusion

Results indicated that the pretreatment of PCP (10.3 g/kg BW) effectively protected against CCl₄-induced acute liver injury, which was comparable to efficacy of silymarin (100 mg/kg). This hepatoprotective effects might be attributed to amelioration of CCl₄-induced oxidative stress via activating Nrf2 signaling pathway.

Electronic supplementary material

The online version of this article (10.1186/s13020-017-0153-x) contains supplementary material, which is available to authorized users.

Selected hepatoprotective herbal medicines: Evidence from ethnomedicinal applications, animal models, and possible mechanism of actions

Insight into the hepatoprotective effects of medicinally important plants is important, both for physicians and researchers. Main reasons for the use of herbal medicine include their lesser cost compared with conventional drugs, lesser undesirable drug reactions and thus high safety, and reduced side effects. The present review focuses on the composition, pharmacology, and results of experimental trials of selected medicinal plants: Silybum marianum (L.) Gaertn., Glycyrrhiza glabra, Phyllanthus amarus Schumach. & Thonn., Salvia miltiorrhiza Bunge., Astragalus membranaceus (Fisch.) Bunge, Capparis spinosa (L.), Cichorium intybus (L.), Solanum nigrum (L.), Sapindus mukorossi Gaertn., Ginkgo biloba (L.), Woodfordia fruticosa (L.) Kurz, Vitex trifolia (L.), Schisandra chinensis (Turcz.) Baill., Cuscuta chinensis (Lam.), Lycium barbarum, Angelica sinensis (Oliv.) Diels, and Litsea coreana (H. Lev.). The probable modes of action of these plants include immunomodulation, stimulation of hepatic DNA synthesis, simulation of superoxide dismutase and glutathione reductase to inhibit oxidation in hepatocytes, reduction of intracellular reactive oxygen species by enhancing levels of antioxidants, suppression of ethanol-induced lipid accumulation, inhibition of nucleic acid polymerases to downregulate viral mRNA transcription and translation, free radical scavenging and reduction of hepatic fibrosis by decreasing the levels of transforming growth factor beta-1, and collagen synthesis in hepatic cells. However, further research is needed to identify, characterize, and standardize the active ingredients, useful compounds, and their preparations for the treatment of liver diseases.

Genistein Binding to Copper(II)-Solvent Dependence and Effects on Radical Scavenging

Genistein, but not daidzein, binds to copper(II) with a 1:2 stoichiometry in ethanol and with a 1:1 stoichiometry in methanol, indicating chelation by the 5-phenol and the 4-keto group of the isoflavonoid as demonstrated by the Jobs method and UV-visible absorption spectroscopy. In ethanol, the stability constants had the value 1.12 × 10¹¹ L²∙mol^-2 for the 1:2 complex and in methanol 6.0 × 10⁵ L∙mol^-1 for the 1:1 complex at 25 °C. Binding was not detected in water, as confirmed by an upper limit for the 1:1 stability constant of K = 5 mol^-1 L as calculated from the difference in solvation free energy of copper(II) between methanol and the more polar water. Solvent molecules compete with genistein as demonstrated in methanol where binding stoichiometry changes from 1:2 to 1:1 compared to ethanol and methanol/chloroform (7/3, v/v). Genistein binding to copper(II) increases the scavenging rate of the stable, neutral 2,2-diphenyl-1-picrylhydrazyl radical by more than a factor of four, while only small effects were seen for the short-lived but more oxidizing β-carotene radical cation using laser flash photolysis. The increased efficiency of coordinated genistein is concluded to depend on kinetic rather than on thermodynamic factors, as confirmed by the small change in reduction potential of -0.016 V detected by cyclic voltammetry upon binding of genistein to copper(II) in methanol/chloroform solutions.

European contribution to the study of ROS: A summary of the findings and prospects for the future from the COST action BM1203 (EU-ROS)

The European Cooperation in Science and Technology (COST) provides an ideal framework to establish multi-disciplinary research networks. COST Action BM1203 (EU-ROS) represents a consortium of researchers from different disciplines who are dedicated to providing new insights and tools for better understanding redox biology and medicine and, in the long run, to finding new therapeutic strategies to target dysregulated redox processes in various diseases. This report highlights the major achievements of EU-ROS as well as research updates and new perspectives arising from its members. The EU-ROS consortium comprised more than 140 active members who worked together for four years on the topics briefly described below. The formation of reactive oxygen and nitrogen species (RONS) is an established hallmark of our aerobic environment and metabolism but RONS also act as messengers via redox regulation of essential cellular processes. The fact that many diseases have been found to be associated with oxidative stress established the theory of oxidative stress as a trigger of diseases that can be corrected by antioxidant therapy. However, while experimental studies support this thesis, clinical studies still generate controversial results, due to complex pathophysiology of oxidative stress in humans. For future improvement of antioxidant therapy and better understanding of redox-associated disease progression detailed knowledge on the sources and targets of RONS formation and discrimination of their detrimental or beneficial roles is required. In order to advance this important area of biology and medicine, highly synergistic approaches combining a variety of diverse and contrasting disciplines are needed.

Molecular and biochemical evidence on the protective role of ellagic acid and silybin against oxidative stress-induced cellular aging

Aging is a natural process in living organisms that is defined by some molecular and cellular changes with time. Various causes such as mitochondrial DNA aberrations, aggregation of proteins, telomere shortening, and oxidative stress have an influential role in aging of the cells. Natural antioxidants are compounds that are potent to protect the body from detrimental effects of molecules such as free radicals. The aim of this study was to evaluate the anti-aging properties of ellagic acid (EA) and silybin (SIL), as natural antioxidant compounds on rat embryonic fibroblast (REF) cells. These cells were pre-incubated with EA and SIL, thereafter were exposed to hydrogen peroxide (H₂O₂). Then, the cell viability, SA-β-GAL activity, distribution of cell cycle, NF-κB, and mitochondrial complex I, II/IV enzyme activity were measured. The results of this study revealed the protective effects of EA and SIL in H₂O₂-treated REF cells, which confirm the previous achieved data on antioxidant and anti-inflammatory characteristics of EA and SIL against H₂O₂ in the treated REF cells. However, more new in vivo experiments are required to discover the anti-aging effects and mechanism of action of such compounds.

Modulatory effect of silymarin on nuclear factor-erythroid-2-related factor 2 regulated redox status, nuclear factor-κB mediated inflammation and apoptosis in experimental gastric ulcer

Non-steroidal anti-inflammatory drugs (NSAIDs) consumption has been commonly associated with gastric mucosal lesions including gastric ulcer. Silymarin (SM) is a flavonoid mixture with anti-oxidant and anti-inflammatory activities which explain its protective role against hepatic and renal injuries. However, its impact on gastric ulcer has not yet been elucidated. Thus we went further to investigate the potential protective effects of SM against indomethacin-induced gastric injury in rats. Pretreatment with SM (50 mg/kg orally) attenuated the severity of gastric mucosal damage as evidenced by decreasing ulcer index (UI) and ulcer score, improvement of disturbed histopathologicl features to be insignificant with those induced by the reference anti-ulcer drug. Pretreatment with SM also suppressed gastric inflammation by decreasing myeloperoxidase activity, tumer necrosis factor-α (TNF- α) and interleukin 6 (IL6) levels along with nuclear factor kappa B p65 (NF-κB) expression. Meanwhile, SM prevent gastric oxidative stress via inhibition of lipid peroxides formation, enhancement of glutathione peroxidase, superoxide dismutase activities and up-regulation of nuclear factor-erythroid-2-related factor 2 (Nrf2), the redox-sensitive master regulator of oxidative stress signaling. In conclusion, the results herein revealed that SM has a gastro-protective effect which is mediated via suppression of gastric inflammation, oxidative stress, increased the anti-oxidant and the cyto-protective defense mechanisms.

Rationale of combination therapy with antioxidants in medical management of Peyronie's disease: results of clinical application

Peyronie's disease (PD) is a connective tissue disorder involving the tunica albuginea of the corpora cavernosa of the penis. We have published several studies describing a "combined therapy" for PD patients, but the present study aims to clearly demonstrate how the association between various antioxidants in PD treatment can significantly increase the likelihood of therapeutic success. We used the following substances: silymarin, ginkgo biloba, vitamin E, bilberry, topical diclofenac sodium, and pentoxifylline (PTX). We analyzed the therapeutic impact and possible side effects of one or more antioxidants in patients with early-stage PD. To clearly prove that it is possible to achieve better results when combining more than one agent, we designed this study with five treatment groups, corresponding, respectively, to the administration of a single oral antioxidant; two oral antioxidants; three oral antioxidants; five oral antioxidants + local diclofenac; and five oral antioxidants + local diclofenac + PTX by perilesional injection. One hundred and twenty patients were assigned to five groups of treatment designed according to the abovementioned study aim. Outcomes after 6 months of treatment showed that combined antioxidant therapy is effective in treating PD. Statistical analysis showed significant differences between the treatment groups with regard to: improvement and disappearance of penile pain; percentage of reduction in the volume of penile plaque; reduction in penile curvature; recovery of erectile function in patients with erectile dysfunction; increase in the International Index of Erectile Function score; and reduction of psychosexual impact. Furthermore, we observed that the clinical efficacy of combined therapy is greater when topical use of diclofenac gel and perilesional injection of PTX are added to oral treatment with more than one antioxidant. Although several articles have already been published reporting the effectiveness of combined treatment in PD, this is the first study clearly proving how, as the number of substances used in treatment rises, a proportionally greater therapeutic effect is achieved.

Herbal Medications in Cardiovascular Medicine

Herbal medications are commonly used for clinical purposes, including the treatment of cardiovascular conditions. Compared with conventional medications, herbal medications do not require clinical studies before their marketing or formal approval from regulatory agencies, and for this reason their efficacy and safety are rarely proven. In this review, we summarize available evidence on herbal medications mostly used in cardiovascular medicine. We show that the use of these medications for the treatment of cardiovascular diseases is often not supported by scientific evidence. Despite most of these herbs showing an effect on biological mechanisms related to the cardiovascular system, data on their clinical effects are lacking. Potential relevant side effects, including increased risk of drug interactions, are described, and the possibility of contamination or substitution with other medications represents a concern. Physicians should always assess the use of herbal medications with patients and discuss the possible benefits and side effects with them.

Antigenotoxicity protection of Carapa guianensis oil against mitomycin C and cyclophosphamide in mouse bone marrow

The aim of this study was to evaluate the possible protective of C. guianensis oil against MMC and CP, which are direct- and indirect-acting chemical mutagens, using the micronucleus test. Three experiments were performed. First the C. guianensis oil was co-administered to mice at doses of 250, 500 and 1000 mg/kg bw with 4 mg/kg bw MMC or 50 mg/kg bw CP. Second, the mutagenic drug (CP) was administered ip 50 mg/kg bw and after 6 and 12 hours 250 and 500 mg/kg bw of C. guianensis oil were administered. In the last, C. guianensis oil was administrated (250 and 500 mg/kg bw) during five days and after it was administered ip 50 mg/kg bw CP. The results obtained showed that the C. guianensis oil is not cytotoxic neither genotoxic to mouse bone marrow. Regarding the antimutagenic effect, all doses of C. guianensis oil were significantly (p < 0.05) effective in reducing the frequency of micronucleated polychromatic erythrocytes, when compared with MMC or CP alone. Based on these results, our results suggest that the C. guianensis oil shows medicinal potential as an antimutagenic agent, modulating the mutagenicity caused by both direct- and indirect-acting chemical mutagens, in a mammalian model.