Green tea extract supplement reduces D-galactosamine-induced acute liver injury by inhibition of apoptotic and proinflammatory signaling

Injectable hydrogel with doxorubicin-loaded ZIF-8 nanoparticles for tumor postoperative treatments and wound repair

The need for tumor postoperative treatments aimed at recurrence prevention and tissue regeneration have raised wide considerations in the context of the design and functionalization of implants. Herein, an injectable hydrogel system encapsulated with anti-tumor, anti-oxidant dual functional nanoparticles has been developed in order to prevent tumor relapse after surgery and promote wound repair. The utilization of biocompatible gelatin methacryloyl (GelMA) was geared towards localized therapeutic intervention. Zeolitic imidazolate framework-8@ceric oxide (ZIF-8@CeO2, ZC) nanoparticles (NPs) were purposefully devised for their proficiency as reactive oxygen species (ROS) scavengers. Furthermore, injectable GelMA hydrogels loaded with ZC NPs carrying doxorubicin (ZC-DOX@GEL) were tailored as multifunctional postoperative implants, ensuring the efficacious eradication of residual tumor cells and alleviation of oxidative stress. In vitro and in vivo experiments were conducted to substantiate the efficacy in cancer cell elimination and the prevention of tumor recurrence through the synergistic chemotherapy approach employed with ZC-DOX@GEL. The acceleration of tissue regeneration and in vitro ROS scavenging attributes of ZC@GEL were corroborated using rat models of wound healing. The results underscore the potential of the multifaceted hydrogels presented herein for their promising application in tumor postoperative treatments.

Assessing the Hepatic Safety of Epigallocatechin Gallate (EGCG) in Reproductive-Aged Women

A similar abstract of the interim analysis was previously published in Fertility and Sterility. EPIGALLOCATECHIN GALLATE (EGCG) FOR TREATMENT OF UNEXPLAINED INFERTILITY ASSOCIATED WITH UTERINE FIBROIDS (PRE-FRIEND TRIAL): EARLY SAFETY ASSESSMENT. Uterine fibroids are the most common cause of unexplained infertility in reproductive-aged women. Epigallocatechin gallate (EGCG), a green tea catechin, has demonstrated its ability to shrink uterine fibroids in prior preclinical and clinical studies. Hence, we developed an NICHD Confirm-funded trial to evaluate the use of EGCG for treating women with fibroids and unexplained infertility (FRIEND trial). Prior to embarking on that trial, we here conducted the pre-FRIEND study (NCT04177693) to evaluate the safety of EGCG in premenopausal women. Specifically, our aim was to assess any adverse effects of EGCG alone or in combination with an ovarian stimulator on serum liver function tests (LFTs) and folate level. In this randomized, open-label prospective cohort, participants were recruited from the FRIEND-collaborative clinical sites: Johns Hopkins University, University of Chicago, University of Illinois at Chicago, and Yale University. Thirty-nine women, ages ≥18 to ≤40 years, with/without uterine fibroids, were enrolled and randomized to one of three treatment arms: 800 mg of EGCG daily alone, 800 mg of EGCG daily with clomiphene citrate 100 mg for 5 days, or 800 mg of EGCG daily with Letrozole 5 mg for 5 days. No subject demonstrated signs of drug induced liver injury and no subject showed serum folate level outside the normal range. Hence, our data suggests that a daily dose of 800 mg of EGCG alone or in combination with clomiphene citrate or letrozole (for 5 days) is well-tolerated and is not associated with liver toxicity or folate deficiency in reproductive-aged women.

Bromelain ameliorates D-galactosamine-induced acute liver injury: role of SIRT1/LKB1/AMPK, GSK3β/Nrf2 and NF-κB p65/TNF-α/caspase-8, -9 signalling pathways

OBJECTIVES

The present research focused on estimating, for the first time, the potential protective effects of bromelain against D-galactosamine-induced acute liver injury in rats as well as identifying the possible underlying mechanisms.

METHODS

Silymarin (100 mg/kg/day, p.o.) as a reference drug or bromelain (20 and 40 mg/kg/day, p.o.) were administered for 10 days, and on the 8th day of the experiment, a single dose of galactosamine (400 mg/kg/i.p.) induced acute liver injury.

KEY FINDINGS

Pretreatment with bromelain improved liver functions and histopathological alterations induced by galactosamine. Bromelain ameliorated oxidative stress by inducing SIRT1 protein expression and increasing LKB1 content. This resulted in phosphorylating the AMPK/GSK3β axis, which stimulated Nrf2 activation in hepatic cells and thus increased the activity of its downstream antioxidant enzymes [HO-1 and NQO1]. Besides, bromelain exerted significant anti-apoptotic and anti-inflammatory effects by suppressing hepatic contents of TNF-α, NF-κB p65, as well as caspase-8 and caspase-9. The protective effects of bromelain40 were proved to be better than silymarin and bromelain20 in most of the assessed parameters.

CONCLUSIONS

Our results highlight the significant hepatoprotective effects of bromelain against acute liver injury through modulation of SIRT1/LKB1/AMPK, GSK3β/Nrf2 signalling in addition to NF-κB p65/TNF-α/ caspase-8 and -9 pathway.

Ginger and 6-gingerol prevent lipopolysaccharide-induced intestinal barrier damage and liver injury in mice

BACKGROUND

Inflammation-related diseases present a significant public health problem. Ginger is a flavoring spice and medicinal herb with anti-inflammatory activity. This study investigated the preventive effects of ginger extract (GE) and its main bioactive component, 6-gingerol (6G), on lipopolysaccharide (LPS)-induced intestinal barrier dysfunction and liver injury in mice.

RESULTS

GE and 6G were orally administered to mice for seven consecutive days before LPS administration. After 24 h, the mice were sacrificed. GE and 6G were found to significantly reverse LPS-induced inflammation in the mouse ileum by modifying the NF-κB pathway. They also alleviated apoptosis in the ileum by downregulating Bax and cytochrome c gene expression and by inhibiting the caspase-3 pathway. Through the aforementioned mechanisms, GE and 6G restored the intestinal barrier by increasing ZO-1 and claudin-1 protein expressions. Gut-derived LPS induced inflammation and apoptosis in the liver; these effects were markedly reversed through GE and 6G treatment. 6G was the most abundant component in GE, as evidenced through liquid chromatography-mass spectrometry, and accounted for >50% of total gingerols and shogaols in GE.

CONCLUSION

The current results support the use of GE and 6G as dietary supplements to protect against gut-derived endotoxemia-associated inflammatory response and disorders. © 2021 Society of Chemical Industry.

Green Tea Polyphenol Catechins Inhibit Coronavirus Replication and Potentiate the Adaptive Immunity and Autophagy-Dependent Protective Mechanism to Improve Acute Lung Injury in Mice

Effective antiviral therapeutics are urgently required to fight severe acute respiratory syndrome (SARS) caused by a SARS coronavirus (SARS-CoV). Because polyphenol catechins could confer antioxidative, anti-inflammatory, antiviral, and antimicrobial activities, we assessed the therapeutic effects of catechins against SARS-CoV replication in Vero E6 cells, the preventive effect of catechins on CD25/CD69/CD94/CD8⁺ cytotoxic T lymphocytes-mediated adaptive immunity, and the protective effect on lipopolysaccharide-induced acute lung injury (ALI) in mice. We found that catechins containing 32.8% epigallocatechin gallate, 15.2% epicatechin gallate, 13.2 epicatechin, 10.8% epigallocatechin, 10.4% gallocatechin, and 4.4% catechin directly inhibited SARS-CoV replication at sub-micromolecular concentrations. Four-week catechins ingestion increased CD8⁺ T cell percentage, upregulated CD69⁺/CD25⁺/CD94-NKG2A/CD8⁺ T lymphocytes-mediated adaptive immunity, and increased type I cytokines release responding to ovalbumin/alum. Catechins significantly reduced lipopolysaccharide-induced cytokine storm and oxidative stress and ALI by inhibiting PI3K/AKT/mTOR signaling to upregulate Beclin-1/Atg5-Atg12/LC3-II-mediated autophagy mechanism. Pretreatment of autophagy inhibitor 3-Methyladenine reversed the inhibiting effects of catechins on the cytokines and oxidative stress levels and ALI. In conclusion, our data indicated that catechins directly inhibited SARS-CoV replication, potentiated the CD25/CD69/CD94/CD8⁺ T lymphocytes-mediated adaptive immunity and attenuated lipopolysaccharide-induced ALI and cytokine storm by PI3K/AKT/mTOR-signaling-mediated autophagy, which may be applied to prevent and/or treat SARS-CoV infection.

Investigating the Opposing Effect of Two Different Green Tea Supplements on Oxidative Stress, Mitochondrial Function and Cell Viability in HepG2 Cells

Green tea extract (GTE) improves exercise outcomes and reduces obesity. However, case studies indicate contradictory physiology regarding liver function and toxicity. We studied the effect of two different decaffeinated GTE (dGTE) products, from a non-commercial (dGTE1) and commercial (dGTE2) supplier, on hepatocyte function using the human cell model, HepG2. dGTE1 was protective against hydrogen peroxide (H₂O₂)-induced apoptosis and cell death by attenuating oxidative stress pathways. Conversely, dGTE2 increased cellular and mitochondrial oxidative stress and apoptosis. A bioavailability study with dGTE showed the major catechin in GTE, EGCG, reached 0.263 µg·ml^-1. In vitro, at this concentration, EGCG mimicked the protective effect of dGTE1. GC/MS analysis identified steric acid and higher levels of palmitic acid in dGTE2 versus dGTE1 supplements. We demonstrate the significant biological differences between two GTE supplements which may have potential implications for manufacturers and consumers to be aware of the biological effects of supplementation.

The Receptor for Advanced Glycation Endproducts (RAGE) Contributes to Severe Inflammatory Liver Injury in Mice

Background: The receptor for advanced glycation end products (RAGE) is a multiligand receptor involved in a number of processes and disorders. While it is known that RAGE-signaling can contribute to toxic liver damage and fibrosis, its role in acute inflammatory liver injury and septic multiorgan failure is yet undefined. We examined RAGE in lipopolysaccharide (LPS) induced acute liver injury of D-galN sensitized mice as a classical model for tumor necrosis factor alpha (TNF-α) dependent inflammatory organ damage.

Methods: Mice (Rage–/– and C57BL/6) were intraperitoneally injected with D-galN (300 mg/kg) and LPS (10 μg/kg). Animals were monitored clinically, and cytokines, damage associated molecular pattern molecules (DAMPs) as well as liver enzymes were determined in serum. Liver histology, hepatic cytokines as well as RAGE mRNA expression were analyzed. Cellular activation and functionality were evaluated by flow cytometry both in bone marrow- and liver-derived cells.

Results: Genetic deficiency of RAGE significantly reduced the mortality of mice exposed to LPS/D-galN. Hepatocyte damage markers were reduced in Rage–/– mice, and liver histopathology was less severe. Rage–/– mice produced less pro-inflammatory cytokines and DAMPs in serum and liver. While immune cell functions appeared normal, TNF-α production by hepatocytes was reduced in Rage–/– mice.

Conclusions: We found that RAGE deletion attenuated the expression of pro-inflammatory cytokines and DAMPs in hepatocytes without affecting cellular immune functions in the LPS/D-galN model of murine liver injury. Our data highlight the importance of tissue-specific RAGE-signaling also in acute inflammatory liver stress contributing to sepsis and multiorgan failure.

Quercetin Attenuates d-GaLN-Induced L02 Cell Damage by Suppressing Oxidative Stress and Mitochondrial Apoptosis via Inhibition of HMGB1

High mobility group box-1 (HMGB1) plays an important role in various liver injuries. In the case of acute liver injury, it leads to aseptic inflammation and other reactions, and also regulates specific cell death responses in chronic liver injury. HMGB1 has been demonstrated to be a good therapeutic target for treating liver failure. Quercetin (Que), as an antioxidant, is a potential phytochemical with hepatocyte protection and is also considered to be an inhibitor of HMGB1. However, the mechanism of its hepatoprotective effects remains to be characterized. The present study explored whether the hepatoprotective effect of Que antagonizes HMGB1, and subsequent molecular signaling events. Our results indicated that Que protects L02 cells from d-galactosamine (d-GaLN)-induced cellular damage by reducing intracellular reactive oxygen species (ROS) production and apoptotic responses in the mitochondrial pathway. Immunofluorescence and Western blot assays showed that HMGB1 was involved in d-GaLN-induced L02 cell damage. Further research showed that after transfection with HMGB1 short hairpin RNA (shRNA), cell viability was improved, and intracellular ROS production and apoptosis were suppressed. When co-treated with Que, the expression of HMGB1 was decreased significantly, the expression of proteins in the corresponding signal pathway were further reduced, and the production of ROS and apoptosis were further suppressed. Molecular docking also indicated the binding of Que and HMGB1. Taken together, these results indicate that Que significantly improves d-GaLN-induced cellular damage by inhibiting oxidative stress and mitochondrial apoptosis via inhibiting HMGB1.

The antagonistic effect of tamoxifen against d-galactosamine/lipopolysaccharide-induced acute liver failure is associated with reactivation of hepatic nuclear factor-κB

Context: Tamoxifen (TAM) ameliorates D-galactosamine/lipopolysaccharide (Gal/LPS)-induced acute liver failure (ALF) through its antioxidative effect; thus, this study was designed to determine whether the effectiveness of TAM is related to nuclear factor-κB (NF-κB) reactivation. Materials and methods: Experimental mice were injected with TAM once daily for 3 consecutive days intraperitoneally (i.p). Twelve hours after pretreatment, Gal/LPS was given to mice (i.p) for ALF induction. In the positive control group, N-acetylcysteine (NAC) was administered immediately after ALF establishment. Except for survival observation, other animals were sacrificed 7 h after Gal/LPS treatment. Survival and hepatic failure were evaluated. For the oxidation assessment, the reduced/oxidized glutathione (GSH/GSSG) ratio and hepatic superoxide dismutase (SOD) activity were analyzed using both colorimetry and Western blotting. Lastly, hepatic NF-κB activation was measured through Western blot analysis of p65 and IκBα. Results: The results indicated that pretreatment with TAM dramatically attenuated Gal/LPS-induced ALF, as demonstrated by improved survival (70%), decreased transaminase levels, and reversed histopathological manifestation. In addition, the hepatic GSH/GSSG ratio and SOD activity were decreased in the ALF model. However, to some degree, TAM and NAC effectively prevented this undesirable phenomenon in contrast to the ALF model. Western blotting revealed that compared with mice in the ALF model group, mice treated with TAM or NAC showed reactivation of hepatic NF-κB. Conclusions: Taking the results together with those of other studies, we conclude that TAM may attenuate Gal/LPS-induced ALF by antagonizing oxidative stress through NF-κB reactivation.

Bicyclol Attenuates Liver Inflammation Induced by Infection of Hepatitis C Virus via Repressing ROS-Mediated Activation of MAPK/NF-κB Signaling Pathway

Treatment with direct-acting antivirals (DAAs) cures most patients infected with hepatitis C virus (HCV) in the real world. However, some patients, especially those with the underlying advanced liver disease, have a limited reduction of liver injury after achieving a sustained viral response (SVR). Bicyclol was widely used in clinics for the treatment of a variety of liver injuries but with an unknown mechanism for the treatment of hepatitis C. We investigated the anti-inflammatory effects and mechanisms of bicyclol in HCV-infected hepatocytes and further confirmed the putative results in a mouse hepatitis model induced by the coinjection of polyinosinic-polycytidylic acid [poly (I:C)] and D-galactosamine (D-GalN). The results showed that the activation of nuclear factor kappa B (NF-κB) and the subsequent increase of inflammatory factors were directly induced by HCV infection and were persistent after clearance of the virus in Huh7.5 cells. Bicyclol decreased the activation of NF-κB and the levels of inflammatory factors in HCV-infected hepatocytes by inhibiting the activation of the ROS-MAPK-NF-κB pathway, and the effect was synergistic with DAAs in HCV-infected hepatocytes. Bicyclol attenuated the ROS-MAPK-NF-κB axis via recovering mitochondrial function without a dependence on dihydronicotinamide adenine dinucleotide phosphate oxidase and superoxide dismutases. The anti-inflammatory effects and mechanism of bicyclol were verified in mouse hepatitis induced by the coinjection of poly(I:C)/D-GalN. Bicyclol directly ameliorates the chronic inflammation caused by HCV infection and might be used with DAAs or after DAA therapy for ultimately curing chronic hepatitis C.

Green tea extract modulates oxidative tissue injury in beta-thalassemic mice by chelation of redox iron and inhibition of lipid peroxidation

Iron overload in patients with β-thalassemia can cause oxidative organ dysfunction. Iron chelation along with antioxidant supplementation can ameliorate such complications and prolong lives. Green tea extract (GTE) rich in epigallocatechin-3-gallate (EGCG) exhibits anti-oxidation and iron chelation properties in β-knockout thalassemic (BKO) mice diagnosed with iron overload. We investigated the effects of GTE and deferiprone (DFP) alone in combination with one another, and upon the levels of redox-active iron, lipid-peroxidation product, insulin and hepcidin in BKO mice. A state of iron overload was induced in the mice via a trimethylhexanoyl-ferrocene supplemented (Fe) diet for 3 months, and the mice were treated daily with either: DFP (50 mg/kg), DFP (50 mg/kg) plus GTE (50 mg EGCG equivalent/kg), or GTE alone for 2 months. Plasma non-transferrin bound iron (NTBI), malondialdehyde (MDA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepcidin and insulin; tissue iron and MDA were measured. DFP, GTE and GTE + DFP effectively decreased plasma MDA (p < 0.05), NTBI and ALT, and increased plasma hepcidin and insulin. All the treatments also reduced iron accumulation and MDA production in both the pancreas and liver in the mice. However, the combination therapy demonstrated no advantages over monotherapy. The findings suggest GTE improved liver and pancreatic β-cell functions in iron-overloaded β-thalassemia mice by diminishing redox iron and free radicals, while inhibiting lipid peroxidation. Consequently, there are indications that GTE holds significant potential for clinical use.

Modulatory effects of green tea extract against the hepatotoxic effects of 4-nonylphenol in catfish (Clarias gariepinus)

The antioxidant role of the green tea (Camellia sinensis) extract (GTE) was examined to remedy the toxic effects of (0.2mgl^-1) 4-nonylphenol(4-NP). Biochemical parameters, antioxidant enzymes, liver lipid peroxidation (LPO), DNA fragmentation, and apoptosis as well as histopathology of liver of African catfish Clarias gariepinus were considered. Catfishes were divided into four groups: first group (control), second group (0.2mgl^-1 of 4-NP), third group (0.2mgl^-1of 4-NP +100mg GTE l^-1water), and fourth group (0.2mgl^-1 of 4-NP +200mg GTE l^-1water). The results showed that significant increments of serum glucose, AST, ALT, total protein, total lipids, cholesterol, G6PDH, and cortisol. Meanwhile, serum acetylcholinesterase, ALP, and LDH were significantly reduced. In addition, antioxidant enzymes (SOD, CAT, GST, and TAC) levels were reduced in 4-NP treated fish compared to control. Also, there were significant increments in hepatic LPO, DNA fragmentation, and apoptotic erythrocytes in 4-NP treated fish compared to control. Liver of 4-NP treated fish showed some histopathological alterations such as, vacuolization in hepatocytes, congestion in central vein, infiltration of mononuclear inflammatory cells, and necrosis as well as depletion of glycogen content of liver. Addition of green tea extract into the water restored the alterations in most of those biomarkers induced by 4-NP. We concluded that, GTE has a protective role against hepatic failure, depletion of antioxidant defense, and genotoxicity induced 4-NP in C. gariepinus.

Vitamin E (α‑tocopherol) ameliorates aristolochic acid‑induced renal tubular epithelial cell death by attenuating oxidative stress and caspase‑3 activation

Aristolochic acid (AA) is a component identified in traditional Chinese remedies for the treatment of arthritic pain, coughs and gastrointestinal symptoms. However, previous studies have indicated that AA can induce oxidative stress in renal cells leading to nephropathy. α-tocopherol exists in numerous types of food, such as nuts, and belongs to the vitamin E isoform family. It possesses antioxidant activities and has been used previously for clinical applications. Therefore, the aim of the present study was to determine whether α-tocopherol could reduce AA-induced oxidative stress and renal cell cytotoxicity, determined by cell survival rate, reactive oxygen species detection and apoptotic features. The results indicated that AA markedly induced H₂O₂ levels and caspase-3 activity in renal tubular epithelial cells. Notably, the presence of α-tocopherol inhibited AA-induced H₂O₂ and caspase-3 activity. The present study demonstrated that antioxidant mechanisms of α-tocopherol may be involved in the increased survival rates from AA-induced cell injury.

Role of Human Wharton's Jelly Derived Mesenchymal Stem Cells (WJ-MSCs) for Rescue of d-Galactosamine Induced Acute Liver Injury in Mice

BACKGROUND/AIM

Mesenchymal stem cells (MSCs) are multipotent precursor cells having self-renewal ability making them a candidate for use in regenerative medicine. Acute liver injury results in sudden loss of hepatic function leading to organ failure. Liver transplantation is often required to salvage patients with acute liver failure. Due to shortage of organs, identification of alternate method is the need of the hour. In view of this, an attempt has been made to check the regenerative ability of WJ-MSCs (wharton's jelly derived MSC) in mice models for acute liver injury.

METHODS

Swiss albino mice weighing 25 ± 5 g were used in this study. The control mice (Group I), was given saline. Group II mice received d-Galactosamine (d-GalN-800 mg/kg; i.p). Group III mice similar with Group II, received WJ-MSCs (5 × 105 cells/0.5 ml DMEM) through tail vein, 24 h after d-GalN administration and Group IV mice received MSC alone.

RESULTS

Parameters, indicative of hepatotoxicity and oxidative stress were analyzed. A two-fold elevation in the marker enzymes of liver toxicity such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (SAP), and total serum bilirubin (TBIL) confirms hepatocellular injury, while a greater than four-fold increase in malondialdehyde (MDA) formation, along with around 40% fall in superoxide-dis-mutase (SOD) activity was indicative of oxidative stress and loss of hepatocellular membrane integrity induced by d-GalN. The above biochemical and pathological changes were significantly restored in mice that received WJ-MSCs indicating hepatoprotective and probable regenerative property.

CONCLUSION

The present study showed that WJ-MSC treatment is able to rescue/ameliorate the hepatotoxicity induced by d-GalN in mice.

Liver toxicity mechanisms of herbs commonly used in Latin America

Mexico owns approximately 4500 medicinal plants species, a great diversity that position it at the second place after China. According to the Mexican health department, 90% of common population consumes them to treat various diseases. Additionally, herbal remedies in Latin America (LA) are considered a common practice, but the frequency of use and the liver damage related to its consumption is still unknown. Despite the high prevalence and indiscriminate herbal consumption, the exact mechanism of hepatotoxicity and adverse effects is not fully clarified and is still questioned. Some herb products associated with herb induced liver injury (HILI) are characterized by presenting a different chemical composition that may vary from batch to batch, also the biological activity of many medicinal plants and other natural products are directly related to their most active component and its concentration. There are two main biological components that are associated with liver damage, alkaloids, and flavonoids, which are frequent constituents of commonly used herbs. The interaction with the different cytochrome P-450 isoforms, inflammatory, and oxidative activities seem to be the main damage pathway involved in the liver. It is important to know the herbal adverse effects and mechanisms involved; therefore, this article is focused on the beneficial and deleterious effects as well as the possible toxicity mechanisms and interactions of the herbs that are frequently used in LA, since the herb-host interaction may not always be the expected or desired depending on the clinical context in which it is administered.

Steroidal Alkaloids as an Emerging Therapeutic Alternative for Investigation of Their Immunosuppressive and Hepatoprotective Potential

The compounds, sarcovagine-D, alkaloid-C, and holaphylline isolated from Sarcococca saligna were found to possess immunosuppressive activities. These compounds were characterized for in vitro inhibition on human T-cells proliferation and IL-2 production. The compounds showed significant immunosuppressive effect on IL-2 production as well as on phytohemagglutinin stimulated T-cell proliferation in a dose dependent manner. Of all the tested compounds holaphylline was found to be less toxic and safe. These compounds were then evaluated for their in vivo hepatoprotective potential against CCl₄, in which alkaloid-C and holaphylline showed markedly reduced liver inflammation and biochemical parameter (ALT, AST, and ALP) of liver injury. The decrease in the activity of hepatic antioxidant enzyme (SOD) was significantly prevented by holaphylline, likewise gradually the levels of MDA and GSH were also normalized compared to silymarin. The CCl₄ induced inflammation and necrosis around the central vein of liver was reduced by sarcovagine-D, alkaloid-C and holaphylline, to 8%, 4% to 1% respectively as assessed by histopathology, thus having better hepatoprotective effect compared to positive control. Steroidal alkaloids attenuated the inflammation of liver around the injured central vein region by down regulating the CCl₄ induced activation of hepatic macrophages as well as their number respectively. Therefore, the in vitro and in vivo results suggest that steroidal alkaloids from S. saligna could be excellent immunosuppressive and hepatoprotective agents.

Combined treatment with vitamin C and methotrexate inhibits triple-negative breast cancer cell growth by increasing H2O2 accumulation and activating caspase-3 and p38 pathways

Methotrexate (MTX) is widely used as both an anticancer and anti-rheumatoid arthritis drug. Although MTX has been used to inhibit the growth of many cancer cells, it cannot effectively inhibit growth of triple-negative breast cancer cells (TNBC cells). Vitamin C is an antioxidant that can prevent oxidative stress. In addition, vitamin C has been applied as adjunct treatment for growth inhibition of cancer cells. Recent studies indicated that combined treatment with vitamin C and MTX may inhibit MCF-7 and MDA-MB-231 breast cancer cell growth through G2/M elongation. However, the mechanisms remain unknown. The aim of the present study was to determine whether combined treatment with low-dose vitamin C and MTX inhibits TNBC cell growth and to investigate the mechanisms of vitamin C/MTX-induced cytotoxicity. Neither low-dose vitamin C alone nor MTX alone inhibited TNBC cell growth. However, combined low-dose vitamin C and MTX had synergistic anti-proliferative/cytotoxic effects on TNBC cells. In addition, co-treatment increased H2O2 levels and activated both caspase-3 and p38 cell death pathways.

Absence of DCIR1 reduces the mortality rate of endotoxemic hepatitis in mice

Dendritic cell immunoreceptor (DCIR) is a C-type lectin with an immunoreceptor tyrosine-based inhibitory motif (ITIM). Mice lacking DCIR1 (Dcir1^-/- mice) show higher susceptibility to chronic arthritis with increasing age, suggesting that DCIR1 is involved in immune modulation via its ITIM. However, the role of DCIR1 in acute immune responses is not clear. In this study, we explored its role in acute experimental hepatitis. Upon injection of d-galactosamine and lipopolysaccharide, Dcir1^-/- mice showed decreased mortality rates and serum levels of alanine aminotransferase. In early onset hepatitis, serum levels of TNF-α, which primarily cause inflammation and hepatocyte apoptosis, were significantly lower in Dcir1^-/- mice than in WT mice. In the liver of Dcir1^-/- mice, influx of neutrophils and other leukocytes decreased. Consistently, the levels of neutrophil-chemoattractant chemokine CXCL1/KC, but not CXCL2/MIP-2, were lower in Dcir1^-/- mice than in WT mice. However, chemotaxis of Dcir1^-/- neutrophils to CXCL1/KC appeared normal. Pervanadate treatment induced binding of DCIR1 and Src homology region 2 domain-containing phosphatase (SHP)-2, possibly leading to CXCL1/KC expression. These results suggest that DCIR1 is involved in exacerbation of endotoxemic hepatitis, providing a new therapeutic target for lethal hepatitis.

Hepatoprotective activity of viscosine is mediated by attenuation of hepatic macrophages and iNOS expression in CCl4-intoxicated rats

This study investigated the molecular mechanism(s) of the protective effects of a C-alkylated flavonoid, viscosine on an animal model of CCl₄-induced hepatotoxicity. Viscosine at 20, 50 and 100 mg kg^-1 was orally administered in a dose dependent manner per day for 3 days before the CCl₄ (1 : 1 v/v in olive oil, 1 ml kg^-1) treatment and 2 days after the treatment. Hepatoprotection was assessed in terms of reduction in serum enzyme activities (ALT, AST, and ALP) that occur after CCl₄ injury, and by histopathology and immunohistochemistry. The rise in serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in CCl₄-intoxicated rats was markedly suppressed by viscosine in a concentration dependent manner. The decrease in the activity of hepatic antioxidant enzyme, SOD, was significantly prevented by viscosine, likewise gradually the levels of MDA and GSH were also normalized compared to silymarin. Viscosine also reduced the CCl₄-induced damaged area from 2% to 0% as assessed by histopathology and prevented the mixed inflammatory infiltrate. Viscosine attenuated the inflammation in the liver around the injured central vein region by downregulating the CCl₄ induced activation of hepatic CD68+ macrophages, thereby reducing their number as well. The expression of inducible nitric oxide synthase (iNOS) was more potentially suppressed by viscosine compared to the FDA approved positive control silymarin. The results of this study indicate that viscosine could be effective in protecting the liver from acute CCl₄-induced injury. The hepatoprotective mechanisms of viscosine may be related to the free radical scavenging and attenuation of oxidative stress, as well as to the inhibition of inflammatory response in the liver. Here, we are proposing a novel mechanism of action of viscosine and suggesting that it may be a safe and better in vivo antioxidant.

Correlation of In Vivo and In Vitro Assay Results for Assessment of Free Radical Scavenging Activity of Green Tea Nutraceuticals

Green tea (GT)-derived catechins; epigallocatechin gallate (EGCG) in particular are commonly used nutraceuticals for their free-radical scavenging activity (FRSA). The influence of photodegradation on the protective power of GT nutracenticals against oxidative stress was thoroughly explored. Photodegradation of GT extracts was carried out and monitored using orthogonal stability-indicating testing protocol; in vitro and in vivo assays. Total polyphenol content (TPC) and FRSA were determined spectrophotometrically while EGCG was selectively monitored using SPE-HPLC. In vivo assessment of photodegraded samples was investigated via measuring a number of biomarkers for hepatic oxidative stress and apoptosis (caspase-3, inducible nitric oxide synthase, nitric oxide, mitogen-activated protein kinase, glutathione, thiobarbituric acid reactive substances, nuclear factor kappa beta, and nuclear factor erythroid 2-related factor) as well as liver damage (alanine transaminase and aspartate transaminase) in serum of rats previously subjected to oxidative stress. Results showed complete degradation of EGCG in photodegraded green tea samples with no correlation with either TPC or FRSA. On the other hand, in vivo assay results revealed not only loss of activity but formation of harmful pro-oxidants. Photostability was found crucial for the protective effect of GT extract against lead acetate insult. Results confirmed that careful design of quality control protocols requires correlation of chemical assays to bioassays to verify efficacy, stability, and most importantly safety of nutraceuticals.

Hepatotoxicity by Dietary Supplements: A Tabular Listing and Clinical Characteristics

Dietary supplements (DS) are extensively consumed worldwide despite unproven efficacy. The true incidence of DS-induced liver injury (DSILI) is unknown but is probably under-diagnosed due to the general belief of safety of these products. Reported cases of herbals and DS-induced liver injury are increasing worldwide. The aim of this manuscript is to report a tabular listing with a description of DS associated with hepatotoxicity as well as review the phenotype and severity of DSILI. Natural remedies related to hepatotoxicity can be divided into herbal product-induced liver injury and DS-induced liver injury. In this article, we describe different DS associated with liver injury, some of them manufactured DS containing several ingredients (Herbalife™ products, Hydroxycut™, LipoKinetix™, UCP-1 and OxyELITE™) while others have a single ingredient (green tea extract, linoleic acid, usnic acid, 1,3-Dimethylamylamine, vitamin A, Garcinia cambogia and ma huang). Additional DS containing some of the aforementioned ingredients implicated in liver injury are also covered. We have also included illicit androgenic anabolic steroids for bodybuilding in this work, as they are frequently sold under the denomination of DS despite being conventional drugs.

Green tea extract attenuates CCl4-induced hepatic injury in male hamsters via inhibition of lipid peroxidation and p53-mediated apoptosis

Keeping in mind the beneficial effects of GTE administration on liver damage, the present study was undertaken to evaluate the hepatoprotective effect of green tea extract (GTE) against carbon tetrachloride (CCl4)-induced liver injuries in male hamsters for 8 weeks. Twenty hamsters were equally divided into 4 groups, the control ones (group I) received only dis. water. Hamsters of group II had free access to 10% of GTE, while hamsters of group III received 1 ml/kg of 50% CCl4 in corn oil via gavage daily. Hamsters of group IV (GTE + CCl4) received a free access to GTE supplementation in combination with 1 ml/kg of 50% CCl4 in corn oil via gavage daily. Lipid profile, hepatic enzyme levels and apoptosis molecular marker (p53) were investigated in hamsters. GTE + CCl4 treated hamsters showed lower levels of hepatic malondialdehyde (MDA) than CCl4 exposed hamsters. Hepatic activity levels of GSH, ALD and cytochrome 450 reductase were declined after CCl4 administration while they were remarkably improved with GTE administration. Serum lipid profiles as T-cholesterol (TC), triglyceride (TG) and low density lipoproteins (LDL) were improved in GTE and CCl4 treated hamsters than CCl4 group. Moreover, hepatic tissue damage and p53 expression induced with CCl4 were improved with the treatment of GTE. These results suggested that GTE possesses hepatoprotective properties against the effect of CCl4.

Vitamin C attenuates the toxic effect of aristolochic acid on renal tubular cells via decreasing oxidative stress‑mediated cell death pathways

Aristolochic acid (AA) is a component of Chinese medicinal herbs, including asarum and aristolochia and has been used in Traditional Chinese Medicine for a long time. Recent studies found that AA has a cytotoxic effect resulting in nephropathy. These studies indicated that AA‑induced cytotoxicity is associated with increases in oxidative stress and caspase‑3 activation. The present study further demonstrated that AA mainly elevates the H2O2 ratio, leading to increases in oxidative stress. Furthermore, the results indicated that AA induces cell death can via caspase‑dependent and ‑independent pathways. It is desirable to identify means of inhibiting AA‑induced renal damage; therefore, the present study applied an anti‑oxidative nutrient, vitamin C, to test whether it can be employed to reduce AA‑induced cell cytotoxicity. The results showed that vitamin C decreased AA‑induced H2O2 levels, caspase‑3 activity and cytotoxicity in renal tubular cells. In conclusion, the present study was the first to demonstrate that AA‑induced increases of the H2O2 ratio resulted in renal tubular cell death via caspase‑dependent and ‑independent pathways, and that vitamin C can decrease AA‑induced increases in H2O2 levels and caspase‑3 activity to attenuate AA‑induced cell cytotoxicity.

Ascorbic acid inhibits TPA-induced HL-60 cell differentiation by decreasing cellular H₂O₂ and ERK phosphorylation

Retinoic acid (RA), vitamin D and 12-O‑tetradecanoyl phorbol-13-acetate (TPA) can induce HL-60 cells to differentiate into granulocytes, monocytes and macrophages, respectively. Similar to RA and vitamin D, ascorbic acid also belongs to the vitamin family. High‑dose ascorbic acid (>100 µM) induces HL‑60 cell apoptosis and induces a small fraction of HL‑60 cells to express the granulocyte marker, CD66b. In addition, ascorbic acid exerts an anti‑oxidative stress function. Oxidative stress is required for HL‑60 cell differentiation following treatment with TPA, however, the effect of ascorbic acid on HL‑60 cell differentiation in combination with TPA treatment remains to be fully elucidated. The aim of the present study was to investigate the cellular effects of ascorbic acid treatment on TPA-differentiated HL-60 cells. TPA-differentiated HL-60 cells were used for this investigation, this study and the levels of cellular hydrogen peroxide (H2O2), caspase activity and ERK phosphorylation were determined following combined treatment with TPA and ascorbic acid. The results demonstrated that low‑dose ascorbic acid (5 µM) reduced the cellular levels of H2O2 and inhibited the differentiation of HL‑60 cells into macrophages following treatment with TPA. In addition, the results of the present study further demonstrated that low‑dose ascorbic acid inactivates the ERK phosphorylation pathway, which inhibited HL‑60 cell differentiation following treatment with TPA.

Role of PECAM-1 in radiation-induced liver inflammation

Platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31) is known to play an important role in hepatic inflammation. Therefore, we investigated the role of PECAM-1 in wild-type (WT) and knock-out (KO)-mice after single-dose liver irradiation (25 Gy). Both, at mRNA and protein level, a time-dependent decrease in hepatic PECAM-1, corresponding to an increase in intercellular cell adhesion molecule-1 (ICAM-1) (6 hrs) was detected in WT-mice after irradiation. Immunohistologically, an increased number of neutrophil granulocytes (NG) (but not of mononuclear phagocytes) was observed in the liver of WT and PECAM-1-KO mice at 6 hrs after irradiation. The number of recruited NG was higher and prolonged until 24 hrs in KO compared to WT-mice. Correspondingly, a significant induction of hepatic tumour necrosis factor (TNF)-α and CXC-chemokines (KC/CXCL1 interleukin-8/CXCL8) was detected together with an elevation of serum liver transaminases (6–24 hrs) in WT and KO-mice. Likewise, phosphorylation of signal transducer and activator of transcription-3 (STAT-3) was observed in both animal groups after irradiation. The level of all investigated proteins as well as of the liver transaminases was significantly higher in KO than WT-mice. In the cell-line U937, irradiation led to a reduction in PECAM-1 in parallel to an increased ICAM-1 expression. TNF-α-blockage by anti-TNF-α prevented this change in both proteins in cell culture. Radiation-induced stress conditions induce a transient accumulation of granulocytes within the liver by down-regulation/absence of PECAM-1. It suggests that reduction/lack in PECAM-1 may lead to greater and prolonged inflammation which can be prevented by anti-TNFα.

Acetaminophen induces JNK/p38 signaling and activates the caspase-9-3-dependent cell death pathway in human mesenchymal stem cells

Acetaminophen (APAP) is a widely used analgesic and antipyretic drug. Generally, the therapeutic dose of APAP is clinically safe, however, high doses of APAP can cause acute liver and kidney injury. Therefore, the majority of previous studies have focussed on elucidating the mechanisms of APAP-induced hepatotoxicity and nephrotoxicity, in addition to examining ways to treat these conditions in clinical cases. However, few studies have reported APAP-induced intoxication in human stem cells. Stem cells are important in cell proliferation, differentiation and repair during human development, particularly during fetal and child development. At present, whether APAP causes cytotoxic effects in human stem cells remains to be elucidated, therefore, the present study aimed to investigate the cellular effects of APAP treatment in human stem cells. The results of the present study revealed that high-dose APAP induced more marked cytotoxic effects in human mesenchymal stem cells (hMSCs) than in renal tubular cells. In addition, increased levels of hydrogen peroxide (H2O2), phosphorylation of c-Jun N-terminal kinase and p38, and activation of caspase-9/-3 cascade were observed in the APAP-treated hMSCs. By contrast, antioxidants, including vitamin C reduced APAP-induced augmentations in H2O2 levels, but did not inhibit the APAP-induced cytotoxic effects in the hMSCs. These results suggested that high doses of APAP may cause serious damage towards hMSCs.

Lycopene stabilizes lipoprotein levels during D-galactosamine/lipopolysaccharide induced hepatitis in experimental rats

OBJECTIVE

To investigate the effect of lycopene on lipoprotein metabolism during D-galactosamine/lipopolysaccharide (D-Gal/LPS) induced hepatitis in experimental rats.

METHODS

The efficacy of lycopene was validated during D-Gal/LPS induced hepatitis by analyzing the activity of lipid metabolizing enzymes such as lipoprotein lipase (LPL), lecithin-cholesterol acyl transferase (LCAT) and hepatic triglyceride lipase (HTGL). Lipo protein analyses were done by the estimation of very low density lipoprotein cholesterol (VLDL), low density lipoprotein cholesterol (LDL) and high density lipoprotein cholesterol (HDL).

RESULTS

The toxic insult of D-galactosamine/lipopolysaccharide (D-Gal/LPS) in experimental group of animals reduces the normal values of lipid metabolizing enzymes due to liver injury. The significant drop in the levels of HDL and concomitant increase in the values of VLDL and LDL were observed. The pretreatment of lycopene restore these altered values to near normal level in experimental group of animals.

CONCLUSIONS

In the light of results, it can be concluded that administration lycopene stabilizes the lipoprotein levels by regulating the lipid metabolizing enzymes through its antioxidant defense and helps to maintain the normal lipid metabolism during toxic injury in liver.

Reduction of oxidative stress attenuates lipoapoptosis exacerbated by hypoxia in human hepatocytes

Chronic intermittent hypoxia, a characteristic of obstructive sleep apnea (OSA), is associated with the progression of simple hepatic steatosis to necroinflammatory hepatitis. We determined whether inhibition of a hypoxia-induced signaling pathway could attenuate hypoxia-exacerbated lipoapoptosis in human hepatocytes. The human hepatocellular carcinoma cell line (HepG2) was used in this study. Palmitic acid (PA)-treated groups were used for two environmental conditions: Hypoxia (1% O2) and normoxia (20% O2). Following the treatment, the cell viability was determined by the 3,4-(5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt (MTS) assay, and the mechanism of lipoapoptosis was evaluated by Western blotting. Hypoxia exacerbated the suppression of hepatocyte growth induced by palmitic acid via activation of mitochondrial apoptotic pathways as a result of endoplasmic reticulum (ER) and oxidative stresses. Ammonium pyrrolidine dithiocarbamate, a scavenger of reactive oxygen species, attenuated the hypoxia-exacerbated lipoapoptosis in hepatocytes, whereas glycerol, which reduces ER stress, did not. This may have been because inhibition of oxidative stress decreases the expression of pro-apoptotic proteins, such as caspase 9 and cytochrome c. These results suggested that modulation of apoptotic signaling pathways activated by oxidative stress can aid in identifying novel therapeutic strategies for the treatment of nonalcoholic steatohepatitis (NASH) with OSA. Further in vivo studies are necessary to understand the pathophysiologic mechanism of NASH with OSA and to prove the therapeutic effect of the modulation of the signaling pathways.

Antioxidative effect of epigallocatechin gallate against D-galactosamine-induced injury in primary culture of rat hepatocytes

Literature data support that green tea and its major component epigallocatechin gallate (EGCG) have powerful antioxidant effects. Contrary, hepatotoxicity can be induced by high-dose EGCG. The timing of exposure to green tea in relation to administration of hepatotoxic agent plays an import role too. The aim of our work was a verification of antioxidative effect of EGCG on D-galactosamine-induced injury in primary culture of rat hepatocytes. Hepatocytes were incubated with EGCG at concentrations of 1.25-10 μM and toxic D-galactosamine (GalN) for 24 hrs. Alternatively, hepatocytes were pretreated with EGCG for 24 hrs, and then incubated with EGCG and GalN for further 24 hrs. Cytotoxicity was analysed by lactate dehydrogenase activity, functional capacity by albumin production. Oxidative stress was evaluated from a production of malondialdehyde and glutathione content in the cells. EGCG protected hepatocytes against GalN-induced cytotoxicity but preventive treatment of intact hepatocytes with EGCG was required to diminish the development of hepatocyte injury. Oxidative stress induced in our study seems to overcome the ability of hepatocytes to improve GSH depletion and albumin production. Prolongation of the pretreatment with EGCG could be a promising strategy leading to amelioration of its hepatoprotective effect.

Vitamin C enhances anticancer activity in methotrexate‑treated Hep3B hepatocellular carcinoma cells

Methotrexate (MTX) has been widely used for rheumatoid arthritis therapy for a long time. MTX is also used as an anticancer drug for various tumors. However, many studies have shown that high-dose MTX treatment for cancer therapy may cause liver and renal damage. Alhough the mechanisms involved in MTX-induced liver and renal damage require further research, many studies have indicated that MTX-induced cytotoxicity is associated with increases in oxidative stress and caspase activation. In order to reduce MTX-induced side-effects and increase anticancer efficiency, currently, combination treatments of low-dose MTX and other anticancer drugs are considered and applied for various tumor treatments. The present study showed that MTX induces increases in H₂O₂ levels and caspase-9/-3 activation leading to cell death in hepatocellular carcinoma Hep3B cells. Importantly, this study is the first to demonstrate that vitamin C can efficiently aid low-dose MTX in inducing cell death in Hep3B cells. Therefore, the present study provides a possible powerful therapeutic method for tumors using a combined treatment of vitamin C and low-dose MTX.

Therapeutic potential of traditional chinese medicine on inflammatory diseases

Increased oxidative stress induces inflammation to several tissues/organs leading to cell death and long-term injury. Traditional Chinese Medicine (TCM) with antioxidant, anti-inflammatory, anti-apoptotic, and autophagic regulatory functions has been widely used as preventive or therapeutic strategy in modern medicine. Oxidative stress and inflammation have been widely reported to contribute to cigarette smoke-induced lung inflammation, hepatotoxicity, or sympathetic activation-induced liver inflammation, lipopolysaccharide-induced renal inflammation, and substance P-mediated neurogenic hyperactive bladder based on clinical findings. In this review, we introduce several evidences for TCM treatment including Monascus adlay (MA) produced by inoculating adlay (Cois lachrymal-jobi L. var. ma-yuen Stapf) with Monascus purpureus on lung injury, Amla (Emblica officinalis Gaertn. of Euphorbiaceae family) on hepatotoxin-induced liver inflammation, Virgate Wormwood Decoction (Yīn Chén Hāo tāng) and its active component genipin on sympathetic activation–induced liver inflammation, and green tea extract and its active components, catechins, or a modified TCM formula Five Stranguries Powder (Wǔ Lén Sǎn) plus Crataegi Fructus (Shān Zhā) on hyperactive bladder. The pathophysiologic and molecular mechanisms of TCM on ameliorating inflammatory diseases are discussed in the review.

Dual role of acetaminophen in promoting hepatoma cell apoptosis and kidney fibroblast proliferation

Acetaminophen (APAP), is a safe analgesic and antipyretic drug at therapeutic dose, and is widely used in the clinic. However, high doses of APAP can induce hepatotoxicity and nephrotoxicity. Most studies have focused on high‑dose APAP‑induced acute liver and kidney injury. So far, few studies have investigated the effects of the therapeutic dose (1/10 of the high dose) or of the low dose (1/100 of the high dose) of APAP on the cells. The aim of this study was to investigate the cellular effects of therapeutic- or low‑dose APAP treatment on hepatoma cells and kidney fibroblasts. As expected, high‑dose APAP treatment inhibited while therapeutic and low‑dose treatment did not inhibit cell survival of kidney tubular epithelial cells. In addition, therapeutic-dose treatment induced an increase in the H2O2 level, activated the caspase‑9/‑3 cascade, and induced cell apoptosis of hepatoma cells. Notably, APAP promoted fibroblast proliferation, even at low doses. This study demonstrates that different cellular effects are exerted upon treatment with different APAP concentrations. Our results indicate that treatment with the therapeutic dose of APAP may exert an antitumor activity on hepatoma, while low‑dose treatment may be harmful for patients with fibrosis, since it may cause proliferation of fibroblasts.

Hautriwaic acid as one of the hepatoprotective constituent of Dodonaea viscosa

It is widely known that hepatitis and its complications such as cirrhosis or hepatocellular carcinoma are one of the major health problems of the world especially since no specific treatment is available. In the present study we investigated the hepatoprotective potential of the methanolic extract of the whole plant of Dodonaea viscosa and its ethyl acetate, aqueous, butanol and n-hexane fractions against carbon tetrachloride (CCl₄) induced hepatoxicity in rats. Hepatoprotection was assessed in terms of reduction in serum enzymes (ALT, AST, and ALP) that occur after CCl₄ injury, and by histopathology and immunohistochemistry. The methanolic extract reduced the serum enzyme level (ALT, AST, and ALP) down to control levels despite CCl₄ treatment. It also reduced the CCl₄-induced damaged area to 0% as assessed by histopathology. The CD68+ macrophages were also reduced in number around the central vein area by the methanolic extract. These hepatoprotective effects were better than the positive control silymarin. Similar hepatoprotective activities were found with the ethyl acetate, and aqueous fractions of the methanolic extract. The butanol and n-hexane fractions showed elevated levels of ALT, AST and ALP as compared to the positive control silymarin. Histopathology showed ∼30% damage to the liver cells with the butanol and n-hexane fractions which still showed some protective activity compared to the CCl₄ treated control. HPLC fingerprinting suggested that hautriwaic acid present in the methanolic extract and its ethyl acetate, and aqueous fractions may be responsible for this hepatoprotective activity of Dodonaea viscosa which was confirmed by in vivo experiments.

Inhibitory effect of Coptis chinensis on inflammation in LPS-induced endotoxemia

ETHNOPHARMACOLOGICAL RELEVANCE

Rhizoma coptidis (RC) has been used as a remedy for inflammation-related diseases in traditional medicine. Although it is known to have anti-inflammatory activities, its mechanism of action on lipopolysaccharide (LPS)-induced inflammation has not yet been identified in detail.

AIM OF THE STUDY

This study was designed to assess the beneficial effects of pretreatment with RC in ameliorating LPS-induced liver inflammation.

MATERIALS AND METHODS

Mice were orally administered RC (500, 1000 mg/kg) for three days in a row. 1h after the last RC administration, the mice were intraperitoneally injected with LPS (35 mg/kg). After treatment, histological alterations and inflammatory factor levels in the liver and proinflammatory cytokines in the serum associated with inflammation were examined.

RESULTS

We found that pretreatment with RC (500 and 1000 mg/kg) exerted a significant protective effect by attenuating liver histopathological changes in endotoxemic mice. The results also demonstrated that RC suppressed secretion of LPS-stimulated pro-inflammatory cytokines, such as interleukin-6 (IL-6). Furthermore, RC inhibited LPS-mediated nuclear factor (NF)-κB activation via the prevention of IκB-α phosphorylation, as well as the phosphorylation of ERK1/2, JNK, and p38 MAPKs. These results were associated with decreases in the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (I-NOS).

CONCLUSIONS

The results presented here clearly demonstrate that RC could significantly protect mice against LPS-induced acute liver injury.

Dried Ginger (Zingiber officinalis) Inhibits Inflammation in a Lipopolysaccharide-Induced Mouse Model

Objectives. Ginger rhizomes have a long history of human use, especially with regards to their anti-inflammatory properties. However, the mechanisms by which ginger acts on lipopolysaccharide-(LPS-)induced inflammation have not yet been identified. We investigated the anti-inflammatory effects of dried Zingiber officinalis (DZO) on LPS-induced hepatic injury. Methods. ICR mice were given a DZO water extract (100, 1000 mg/kg) orally for three consecutive days. On the third day, they were administered by LPS intraperitoneally. To investigate the anti-inflammatory effects of DZO, histological, cytokine expression, and protein factor analyses were performed. Results. Oral administration of DZO significantly reduced pathological changes in the liver and proinflammatory cytokines including interferon-(IFN-)γ and interleukin-(IL-)6 in the serum. In addition, DZO inhibited LPS-induced NF-κB activation by preventing degradation of the IκB-α, as well as the phosphorylation of ERK1/2, SAPK/JNK, and p38 MAPKs. These were associated with a decrease in the expression of inducible nitric oxide synthase (iNOS) and cyclooxyenase-2 (COX-2). Conclusions. Our data provide evidence for the hepatoprotective mechanisms of DZO as an anti-inflammatory effect. Furthermore, use of DZO to treat could provide therapeutic benefits in clinical settings.

Catechins and Sialic Acid Attenuate Helicobacter pylori-Triggered Epithelial Caspase-1 Activity and Eradicate Helicobacter pylori Infection

The inflammasome/caspase-1 signaling pathway in immune cells plays a critical role in bacterial pathogenesis; however, the regulation of this pathway in the gastric epithelium during Helicobacter pylori infection is yet to be elucidated. Here, we investigated the effect of catechins (CAs), sialic acid (SA), or combination of CA and SA (CASA) on H. pylori-induced caspase-1-mediated epithelial damage, as well as H. pylori colonization in vitro (AGS cells) and in vivo (BALB/c mice). Our results indicate that the activity of caspase-1 and the expression of its downstream substrate IL-1β were upregulated in H. pylori-infected AGS cells. In addition, we observed increased oxidative stress, NADPH oxidase gp91phox, CD68, caspase-1/IL-1β, and apoptosis, but decreased autophagy, in the gastric mucosa of H. pylori-infected mice. We have further demonstrated that treatment with CASA led to synergistic anti-H. pylori activity and was more effective than treatment with CA or SA alone. In particular, treatment with CASA for 10 days eradicated H. pylori infection in up to 95% of H. pylori-infected mice. Taken together, we suggest that the pathogenesis of H. pylori involves a gastric epithelial inflammasome/caspase-1 signaling pathway, and our results show that CASA was able to attenuate this pathway and effectively eradicate H. pylori infection.

Hepatoprotective effects of cathepsin B inhibitor on acute hepatic failure induced by lipopolysaccharide/D-galactosamine in mice

BACKGROUND

Increasing evidence suggests that the inactivation of cathepsin B attenuates hepatocyte apoptosis and liver damage. This study aimed to investigate the protective effects of a cathepsin B inhibitor (CA-074me) on lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced acute hepatic failure (AHF) in mice.

METHODS

Mice were intraperitoneally injected with a combination of LPS/D-GalN to induce AHF with or without CA-074me pretreatment. The cumulative survival rates were calculated 48 hours after the induction of AHF. As well as changes in biochemical indicators and liver histology, hepatocyte apoptosis was assessed using a TUNEL method. Serum tumor necrosis factor-alpha (TNF-alpha) production, caspase-3, caspase-8, and caspase-9 activity was evaluated. Cytosolic cytochrome c and Bcl-2 expression were measured by Western blotting.

RESULTS

The marked elevation in serum aminotransferase activity and prothrombin time found in LPS/D-GalN-treated mice was significantly improved by pretreatment with CA-074me. The efficacy of CA-074me was also confirmed by histological analysis and TUNEL assay. The survival rate significantly improved in LPS/D-GalN-induced mice given CA-074me compared with untreated mice. LPS/D-GalN-induced caspase-3 and caspase-9 activation was remarkably suppressed by CA-074me. However, the increased levels of serum TNF-alpha and elevated caspase-8 activity in AHF mice were not significantly reduced by CA-074me. Moreover, CA-074me sharply reduced the increased expression of cytosolic cytochrome c and markedly augmented Bcl-2 expression.

CONCLUSION

These results suggest that CA-074me has a protective effect in acute hepatic failure induced by LPS/D-GalN.

Protective Effects of HV-P411 Complex Against D-Galactosamine-Induced Hepatotoxicity in Rats

This study examined the hepatoprotective effect of the HV-P411 complex, an herbal extract mixture from the seeds of Vitis vinifera, Schisandra chinensis and Taraxacum officinale, against D-galactosamine (D-GalN)-induced hepatitis. Hepatotoxicity was induced by D-GalN (700 mg/kg, i.p.), and the HV-P411 complex was administered orally 48, 24, and 2 h before and 6 h after D-GalN injection. Increases in serum aminotransferase activity and lipid peroxidation and a decrease in hepatic glutathione content were attenuated by the HV-P411 complex 24 h after D-GalN treatment. The HV-P411 complex attenuated the increases in serum tumor necrosis factor-α, interleukin (IL)-6 level and cyclooxygenase-2 protein production and their mRNA expressions, while increases in serum IL-10 level and heme oxygenase-1 protein production and their mRNA expressions were augmented by the HV-P411 complex. The increased translocation of nuclear factor-κB and c-Jun phosphorylation were attenuated by treatment with the HV-P411 complex. Our results suggest that the HV-P411 complex prevents D-GalN-induced hepatotoxicity via antioxidative and anti-inflammatory activities.

Green tea extract supplementation ameliorates CCl4-induced hepatic oxidative stress, fibrosis, and acute-phase protein expression in rat

BACKGROUND/PURPOSE

We evaluated the long-term effects of green tea extract (GTE) supplementation on oxidative stress, biliary acute phase protein expression, and liver function in CCl(4)-induced chronic liver injury.

METHODS

We evaluated the antioxidant activity of GTE in comparison with those of vitamin C, vitamin E, and β-carotene in vitro by using an ultrasensitive chemiluminescence analyzer. Chronic liver injury was induced by intraperitoneally administering carbon tetrachloride (CCl(4)) (1 mL/kg body weight, twice weekly) to female Wistar rats for 8 weeks. The effects of low (4 mg/kg body weight per day) and high (20 mg/kg body weight per day) doses of intragastric GTE on CCl(4)-induced liver dysfunction and fibrosis were examined by measuring the bile and blood reactive oxygen species levels and biochemical parameters by using Western blot and two-dimensional polyacrylamide gel electrophoresis techniques.

RESULTS

GTE has greater scavenging activity against O(2)(-), H(2)O(2), and Hypochlorous acid (HOCl) in vitro than vitamin C, vitamin E, and β-carotene do. In vivo, CCl(4) markedly increased bile and blood reactive oxygen species production, lipid accumulation, number of infiltrated leukocytes, fibrosis, hepatic hydroxyproline content, and plasma alanine aminotransferase and aspartate aminotransferase activities, and reduced plasma albumin levels. Two-dimensional polyacrylamide gel electrophoresis revealed that CCl(4) increased the acute-phase expression of six biliary proteins and decreased hepatic B-cell lymphoma 2 (Bcl-2), catalase, and CuZn superoxide dismutase protein expression. GTE supplementation attenuated CCl(4)-enhanced oxidative stress, levels of biochemical parameters, pathology, and acute-phase protein secretion, and preserved antioxidant/antiapoptotic protein expression.

CONCLUSION

GTE supplementation attenuates CCl(4)-induced hepatic oxidative stress, fibrosis, acute phase protein excretion, and hepatic dysfunction via the antioxidant and antiapoptotic defense mechanisms.