CCl4-induced Oxidative Damage Research Articles

Extraction and characterization of hepatoprotective polysaccharides from Anoectochilus roxburghii against CCl4-induced liver injury via regulating lipid metabolism and the gut microbiota

Anoectochilus roxburghii polysaccharides exhibit notable hepatoprotective effects, but the underlying substance basis and mechanisms remain unknown. In this study, four new polysaccharides named ARP-1a, ARP-1b, ARP-2a and ARP-2b, were isolated from A. roxburghii. Their structural characteristics were systematically analyzed using HPGPC, HPLC, GC–MS, IR and NMR analysis. ARP-1a, the leading polysaccharide isolated from A. roxburghii, was further evaluated for its hepatoprotective effects on acute liver injury mice induced by CCl4. ARP-1a significantly reduced the serum ALT, AST, TNF-α, IL-1β and IL-6 levels, liver MDA content, and increased the SOD and CAT activities and GSH level in liver. H&E staining revealed that ARP-1a pretreatment could markedly relieve liver injury. Further mechanism exploration indicated that ARP-1a could relieve CCl4-induced oxidative damage through activating the Nrf2 signaling. In addition, metabolomics, lipidomics and 16S rRNA amplicon sequencing were used to elucidate the underlying mechanisms of ARP-1a. Multi-omics analysis indicated that ARP-1a exerted hepatoprotective effect against CCl4-induced acute liver injury by regulating lipid metabolism and modulating the gut microbiota. In conclusion, the above results suggest that ARP-1a can be considered a promising and safe candidate for hepatoprotective drug, as well as a potential prebiotic for maintaining intestinal homeostasis and promoting human intestinal health.

Antioxidant and Hepatoprotective Effects of L-Glu and NAC against CCl4-induced Oxidative Damage in Rats. Biochemical and Histopathological Evaluation

Background: The imbalance between free radical formation and antioxidant defence leads to the development of oxidative stress. The search for substances that would mitigate or prevent the effects of oxidative stress remains relevant. Objective: Our goal was to compare the antioxidant and mitigation effects of L-glutamic acid (LGlu) and N-acetylcysteine (NAC) alone or in combination using a battery of biomarkers of oxidative stress such as reduced glutathione (GSH) superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione transferase (GST) and lipid peroxidation, determined as a content of lipid hydroperoxides (LOOH) and thiobarbituric acid reactive substances (TBARS). Histopathological examination of the liver was also performed. Methods: Experimental rats were divided into five experimental groups. Exp.1: was treated with CCl4 only, Exp. 2: was treated with CCl4/L-Glu, Exp. 3: was treated with CCl4/Glu/NAC. Exp. 4: was treated with CCl4/NAC, Control 5: served as the control rats. Results: These findings suggest that the CCl4 leads to oxidative stress by depleting the antioxidant enzyme activities and increasing peroxidation products. The studied biochemical parameters were altered by the introduction of CCl4, which was normalised (to one degree or another) by L-Glu, LGlu/ NAC and NAC treatment. Conclusion: The most remarkable protective effect was observed in groups of rats that were treated with L-Glu only. This conclusion was confirmed by histopathological findings which showed less severe hepatocellular necrosis, fibrosis and inflammation in CCl4/L- Glu and CCl4/L-Glu/NAC treated group, compared to the CCl4 group.

Protective effect of Ceiba pentandra (L) Gaertn on CCl4-induced oxidative stress and liver damage in rats

BackgroundCeiba pentandra (L.) Gaertn, popularly known as the white silk-cotton tree and popularly used in Chinese and Indian traditional medicine. The bark is used to treat diarrhea, pain, fever, cardiac problems, asthma, and gastrointestinal problems. The present study aimed to evaluate the hepatoprotective and antioxidant effects of ethanol extract of C. pentandra bark (EECP-BK) against CCl4-induced hepatic damage in rats. MethodsPreliminary phytochemical analysis was performed to identify the bioactive compounds. CCl4 (40 mM) induced enzymatic changes at HepG2 cells were adopted for the in-vitro model. HepG2 cells were pretreated with EECP-BK (25, 50, 100, and 200 µg/ml) and standard (silymarin 12.5 µg/ml) respectively. Rat model of CCl4-induced liver damage for adopted for the in-vivo model. Rats were pretreated orally with EECP-BK 200 & 400 mg/kg and standard (silymarin 100 mg/kg) for 7 days. Rats were injected with 1 ml/kg of 50% CCl4 on day 8 to induce hepatic damage and were observed for antioxidant levels and serum biomarkers. In addition, in-silico studies have been performed to explore the binding properties of compounds from EECP-BK with tumor necrosis factor-alpha converting enzyme (TACE) targeting hepatic inflammation ResultsThe phytochemical analysis confirmed the presence of glycoside, steroids, phenols, tannins, and saponins. EECP-BK 200 µg/ml showed the highest protection against CCl4 in HepG2 cells. Similarly, silymarin 12.5 µg/ml showed good protection against CCl4. In rats, EECP-BK up to 2000 mg/kg did produce any toxic signs or mortality. CCl4 injection in rats showed elevated liver enzymatic and bilirubin levels and causes liver damage. It also decreased the SOD, CAT, and GSH levels. Pre-treatment with EECP-BK 400 mg/kg showed a significant reduction in SGPT, SGOT, ALP, and total bilirubin levels and increased SOD, CAT, and GSH levels. Similar results were observed with, silymarin treatment also. Furthermore, EECP-BK showed protection over hepatocyte necrosis induced by CCl4 in rats which is evident by histopathology. Molecular docking studies revealed that acacetin 7-rutinoside binds favorably with the active site of TACE with a binding affinity of -8.8 kJ/mol. ConclusionOur findings supported the antioxidative capability of EECP-BK by showing that it protected the liver from CCl4-induced hepatic damage. Additional research is needed to determine its safety profile and to find its molecular mechanism for therapeutic application.

Synergistic hepatoprotective effects of ω-3 and ω-6 fatty acids from Indian flax and sesame seed oils against CCl4-induced oxidative stress-mediated liver damage in rats

Flaxseed (FS) and sesame seed (SS) are traditional and functional foods in traditional Indian medicine for treating various disorders. The present study investigated the hepatoprotective effects of bioactive-fatty acids (FAs) from FS and SS against carbon tetrachloride (CCl4)-induced hepatic damage in rats. Pre and post-treatments for 28 consecutive days significantly increased the activities of in vivo antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), and peroxidase (POX), whereas, lipid peroxidation (LPO) activity was markedly decreased in a dose-dependent manner in liver and kidneys. A significant reduction was observed in the hematological parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and total bilirubin in the serum of post-treated animals compared to the negative control. The results were confirmed histopathologically. The results suggested that the ω-3 and ω-6 FAs from flaxseed oil (FSO) and sesame seed oil (SSO), respectively, showed potential synergistic hepatoprotective and antioxidant effects that were mediated mainly by ω-3 and ω-6 FAs present in the respective seed oils.

Ethanolic Extract of Whole Unripe Plantain Musa paradisiaca Ameliorates Carbon Tetrachloride-Induced Hepatotoxicity and Nephrotoxicity in Wistar Rat

Aim: Globally, burden of liver and kidney diseases has been on the increase in recent times. The present study therefore investigates the hepatoprotective and nephroprotective potentials of unripe plantain Musa paradisiaca on CCl4-induced oxidative damage in albino rat. This was with the aim of providing a locally available and potent therapeutic alternative to the conventional drugs used in the management of liver and kidney diseases.
 Place and Duration of Study: The study was conducted at the Department of Medical Biochemistry, College of Medicine, Ekiti State University, Ado Ekiti between July 2018 and January, 2019. 
 Methodology: Twenty-five adult male albino rats were placed into seven groups of 5 animals each. Group I animals received distilled water throughout the duration of the experiment, while group II were exposed to CCl4 only. Groups III, IV, V and VI received 3 ml/kg b.w of CCl4 intraperitoneally but were post treated with 50 mg/kg and 100 mg/kg of unripe plantain extract respectively while group seven were post-treated with silymarin by oral gavage. Animals were sacrificed for the excision of the liver and kidney. Activities of creatinine kinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), as well as levels of urea, uric acid, bilirubin and lipid profile were assessed. Tissue antioxidant level of reduced glutathione (GSH) and activities of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) were also determined.
 Results: Exposure to CCl4 caused a significant derangement in lipid profile, resulting in the increase in serum triglyceride, total cholesterol and low density lipoprotein (LDL) while high density lipoprotein (HDL) level was diminished. Liver and kidney biomarkers (ALT, AST, ALP, CK, urea, uric acid and bilirubin were also significantly elevated in the serum relative to the control animals following exposure to CCl4. Activities of antioxidant enzymes in the serum were markedly inhibited by CCl4 exposure. Treatment with Musa paradisiaca extract caused a dose-dependent restoration of all biochemical parameters determined, while histopathological observation was in agreement with biochemical results.
 Conclusion: These findings showed that Musa paradisiaca extract exhibited positive modulatory effects on the liver and kidney subjected to oxidative attack, hence, its potential usefulness in the management diseases associated with these organs.

Hepatoprotective Potential of Pomegranate in Curbing the Incidence of Acute Liver Injury by Alleviating Oxidative Stress and Inflammatory Response.

Hepatitis is an inflammatory disease of the liver and is considered one of the leading causes of death worldwide. Due to its scavenging activity, Punica granatum may be used for the treatment and prevention of liver diseases. The current study investigated the protective mechanism underlying the effects of pomegranate against a rat model of carbon tetrachloride–induced liver injury. Intraperitoneal injection of CCl4 resulted in liver inflammation, oxidative stress, and accumulation of lipid in hepatocytes. CCl4 induced a downregulation of superoxide dismutase (SOD), glutathione (GSH), and melonaldehyde (MDA). Pomegranate protection was assessed in terms of biochemical parameters, histopathology, and immunohistochemistry. Promegranate administration decreased inflammation, elevated serum enzymes and ROS production, and countered the debilitating effects caused by CCl4. In addition, CCl4-induced histological changes were absent in the crude pomegranate extract group, which also enhanced the scavenging activity of reactive oxygen species by enhancing the antioxidant defense mechanism as confirmed by detecting MDA, SOD, and GSH expressions. The migration of CD68+ macrophages was halted at the injured area of the central vein and the number of macrophages was reduced to the normal control by the crude extract compared to the positive control silymarin group. Likewise, protective effects of ethylacetate and the aqueous fraction of the crude extract were also observed. However, the butanol and n-hexane fractions displayed increased levels of ALT, AST, and ALP as compared to silymarin. About 25% damage to hepatocytes was observed in the butanol and n-hexane group by histopathological examination, which is a little better compared to the CCl4-treated group. The crude extract and its ethyl acetate and aqueous fractions may be accountable for the hepatoprotective potential of Punica granatum, which was further confirmed by in vivo experiments. Together, these findings confirm that pomegranate exerts hepatoprotective activity against CCl4-induced oxidative stress and liver damage.

Antioxidative and hepatoprotective activities of a novel polysaccharide (LSAP) from Lepista sordida mycelia

A novel alkali-soluble polysaccharide from Lepista sordida (LSAP) mycelia with antioxidative and hepatoprotective activities was characterized. The weight-average molecular weight and number-average molecular weight of LSAP were 1.442×103 and 6.05×102kDa, respectively. LSAP was consisted of glucose (57.9%), xylose (31.8%), and small amounts of rhamnose, arabinose, galactose, glucuronic acid, and galacturonic acid (1.2%–3.1%). The FT-IR and 2D NMR confirmed that LSAP was composed of Xylp, Araf, 4-O-Me-α-D-GlcpA, (1→4)-linked β-D-Glcp, and (1→4)-α-D-GalA, and β-glycosidic linkages between these sugar units. LSAP displayed notable effects on 1,1-dephenyl-2-picryhydrazyl (DPPH) radical scavenging, hydrogen peroxide scavenging, lipid peroxidation inhibitory ability, reducing power and Fe2+ chelating property. These biological effects were further verified by suppressing CCl4-induced oxidative liver damage in mice at doses of 100 and 200mg/kg. Administration of LSAP in mice prior to CCl4 significantly prevented the CCl4-induced elevation in serum alanine aminotransferase, aspartate aminotransferase, and hepatic malondialdehyde. Mice treated with LSAP demonstrated to increase activities in superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the liver. We also found out that LSAP prevented CCl4-induced oxidative liver histological alteration. LSAP may exert hepatoprotective effects against CCl4-induced damage through antioxidant mechanisms in model mice.

Hepatoprotective effect of piceatannol against carbon tetrachloride-induced liver fibrosis in mice.

Piceatannol (3,5,3',4'-trans-tetrahydroxystilbene) is a natural analog and a metabolite of resveratrol present in grapes and red wine. Previous studies have reported that piceatannol exerts a broad spectrum of health benefits including antioxidant, anti-inflammatory, chemopreventive, and neuroprotective effects. However, little is known about the hepatoprotective effect of piceatannol against toxin-induced liver fibrosis. Therefore, the objective of this study is to evaluate the protective effect of piceatannol in a mouse model of CCl4-induced hepatic fibrosis. Oral administration of piceatannol significantly improved the hepatic functions of CCl4-treated mice in both therapeutic and preventive models. Additionally, the immunohistochemical staining results revealed that collagen deposition in CCl4-injected mice was significantly reduced by treatment with piceatannol. Moreover, piceatannol remarkably suppressed the expressions of collagen I, α-smooth muscle protein (α-SMA), and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) induced by CCl4. The anti-fibrotic mechanism of piceatannol was associated with the regulation of the transforming growth factor-β (TGF-β)/Smad signaling pathway. Finally, piceatannol also profoundly alleviated CCl4-induced hepatic oxidative damage by elevating the level of glutathione and catalase activity. Altogether, our current findings suggest that piceatannol may serve as a bioactive agent that inhibits or alleviates toxic-induced fibroproliferative diseases, especially in the prevention of liver fibrosis.

Dendrobium nobile Lindl. alkaloids-mediated protection against CCl4-induced liver mitochondrial oxidative damage is dependent on the activation of Nrf2 signaling pathway

The activation of nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated signaling pathway has been involved in the mechanisms of a variety of protective agents against cellular oxidative stress. We recently demonstrated that Dendrobium nobile Lindl. alkaloids (DNLA), the active ingredients of Dendrobium, protects mice from CCl4-induced liver injury, dependent on the Nrf2 signaling pathway. The present study was aimed to determine whether the protection against mitochondrial oxidative damage plays a role in the mode of action of DNLA on CCl4-induced liver injury, and to further investigate whether the DNLA-conferred mitochondrial beneficial effects is dependent on the activation of Nrf2 signaling. The CCl4-induced acute liver injury model was employed in both wild-type (WT) and Nrf2-knockout (Nrf2−/−) mice. The results showed that in WT mice DNLA reduced CCl4-induced liver injury, accompanied by a significant reduction in CCl4-induced mitochondrial oxidative stress as evidenced by a decrease in mitochondrial H2O2 content and MDA production, and a marked increase in GSH level and Mn-SOD activity. However, these protective effects were significantly attenuated in Nrf2−/− mice. Furthermore, the administration of DNLA improved mitochondrial oxygen consumption, elevated ATP production, and decreased CCl4-induced apoptosis in the WT mice, whereas the DNLA-mediated protections on mitochondrial function were diminished in the Nrf2 null mice. These results demonstrate that the improvement of mitochondrial oxidative stress and mitochondrial dysfunction is implicated in the mechanism of DNLA-mediated protection on CCl4-induced liver injury, and this DNLA-modulated mode of action is dependent on the activation of Nrf2 signaling pathway.

Hepatoprotective Effects of Pleurotus ostreatus Protein Hydrolysates Yielded by Pepsin Hydrolysis

Pleurotus ostreatus protein extract (POPE) was prepared by the alkali precipitation method with 0.3% (w/v) NaOH. POPEP-III with a MW of 3000–5000 Da was acquired by pepsin enenzymatic hydrolysis. POPEP-III displayed noteworthy effects of 1,1-diphenyl-2-picrylhydrazyl DPPH and H2O2 scavenging activities, Fe2+ chelating ability, lipid peroxidation inhibition capacity, and metal reducing power. The administration of POPEP-III in mice significantly prevented prior CCl4-induced strengthen serum ALT and AST activities, changing from 365.44 ± 36.87 IU/L to 220.23 ± 22.27 IU/L and 352.52 IU/L to 206.75 ± 17.26 IU/L, respectively (p < 0.001), and suppressed hepatic malondialdehyde (MDA) formation from 15.28 ± 3.47 nmol/mg prot to 10.04 ± 2.06 nmol/mg prot (p < 0.001). Mice treated with POPEP-III demonstrated augmented activities of superoxide dismutase (SOD) in the liver, from 187.49 ± 19.81 U/mg prot to 233.35 ± 34.23 U/mg prot, and of glutathione peroxidase (GSH-Px), from 84.01 ± 14.54 U/mg prot to 115.9 ± 16.57 U/mg prot (p < 0.05). POPEP-III also prevented CCl4-induced oxidative liver histological alteration. The results suggest that POPEP-III can protect the liver from CCl4-induced oxidative damage.

Hepatocyte-specific deficiency of Nrf2 exacerbates carbon tetrachloride-induced liver fibrosis via aggravated hepatocyte injury and subsequent inflammatory and fibrogenic responses

BackgroundLiver fibrosis, in which hepatocyte damage and inflammatory response play critical roles, is a physiological response to chronic or iterative liver injury and can progress to cirrhosis over time. Nuclear factor E2-related factor 2 (Nrf2) is a master transcription factor that regulates oxidative and xenobiotic stress responses as well as inflammation. MethodTo ascertain the cell-specific roles of Nrf2 in hepatocytes and myeloid lineage cells in the progression of liver fibrosis, mice lacking Nrf2 specifically in hepatocytes [Nrf2(L)-KO] and myeloid lineage cells [Nrf2(M)-KO] were generated to evaluate carbon tetrachloride (CCl4)-induced liver injury, subsequent inflammation and fibrosis. In addition, mouse primary hepatocytes were used to investigate the underlying mechanisms. ResultsNrf2-mediated antioxidant response in the liver is responsive to acute CCl4 exposure in mice. With repeated CCl4 administration, Nrf2(L)-KO, but not Nrf2(M)-KO, mice showed more severe liver fibrosis than Nrf2-LoxP control mice. In addition, in response to acute CCl4 exposure, Nrf2(L)-KO mice displayed aggravated liver injury, elevated lipid peroxidation and inflammatory response compared to control mice. In mouse primary hepatocytes, deficiency of Nrf2 resulted in more severe CCl4-induced lipid oxidation and inflammatory response. ConclusionDeficiency of Nrf2 in hepatocytes sensitizes the cells to CCl4-induced oxidative damage and inflammatory response, which are initiator and enhancer of subsequent hepatic inflammation and fibrosis. Thus, Nrf2 is a critical determinant of liver injury and fibrosis in response to CCl4, suggesting that Nrf2 might be a valuable target for the intervention.

The effect of two formulations of carbon enterosorbents on oxidative stress indexes and molecular conformation of serum albumin in experimental animals exposed to CCl4

The liver failure means inability to perform its normal synthetic, biotransformation and excretory functions. The disturbance of metabolic processes leads to the development of "metabolic endogenous intoxication" resulting in oxidative stress. Oxidative stress initiates the processes of oxidation of amino acid residues of blood plasma proteins causing the changes in their structure and functions. The effect of administration of highly activated porous carbonic enterosorbents on oxidative stress manifestations and molecular conformation of serum albumin in blood of experimental animals with acute liver failure induced by carbon tetrachloride (CCl4) needs to be investigated. Two forms of activated carbonic enterosorbents such as AC1 (primary beads with the range of diameters of 125–250 μm) and AC2 (secondary granules prepared from micronized AC1 having the mean particle size of ~1 μm) derived from phenol-formaldehyde resin were used in rat model with CCl4 intoxication. The total level of reactive oxygen species (ROS) in blood plasma, the activity of catalase (CAT) in blood hemolysates; the content of reduced glutathione (GSH) in liver homogenates, and the level of oxidative modification of proteins (OMP) such as aldehyde-dinitrophenylhydrazone (A-DNPH) and ketone-dinitrophenylhydrazone (K-DNPH) derivatives in blood plasma and liver homogenates were determined. In addition, the level of pro/antioxidant ratio in blood hemolysates and the content of lipid peroxidation product - malondialdehyde (MDA), in blood plasma and liver were determined. Melting thermograms of blood plasma proteins (BPP) and molecular conformation changes of serum albumin were analyzed by biophysical methods (differential scanning microcalorimetry and spectrofluorimetry). The extent of CCl4-induced oxidative damage in blood and liver of experimental animals was shown to be less expressed for AC1 in comparison with AC2 enterosorbent. However, AC2 used in the form of secondary granules positively influenced some biophysical properties of albumin molecule (temperature of melting, shape of melting endotherm and intrinsic fluorescence) after rats exposure to CCl4. In general, administration of both AC1 and AC2 led to the reduction of oxidative stress manifestations and partial restoration of native molecular conformation of serum albumin. These observations are promising in terms of achieving recovery of detoxification potential of organism after severe liver injury.

Hepatoprotective Effect of Tagetes Erecta L. Extract on Carbon Tetrachloride Induced Hepatotoxicity in Rats

Tagetes erecta L. is a widespread garden plant that is commonly known as the marigold, and it is widely used as a medicinal herb for its anti-inflammatory, analgesic, and anti-edematous properties, which are important for phytotherapeutic, dermatological and cosmetic applications. In this study, the protective effects of water extract of Tagetes erecta L. against liver damage were evaluated in carbon tetrachloride (CCl4)-induced chronic hepatotoxicity in rats. The results showed that the treatment of extract significantly lowered the CCl4-induced serum levels of hepatic enzyme markers (GOT, GPT, ALP, and total bilirubin Liver histopathology showed that extract reduced the incidence of liver lesions including hepatic cells cloudy swelling, lymphocytes infiltration, hepatic necrosis, and fibrous connective tissue proliferation induced by CCl4 in rats. Therefore, the results of this study suggest that Tagetes erecta L. Extract could protect liver against the CCl4-induced oxidative damage in rats, and this hepatoprotective effect might be contributed to its modulation on detoxification enzymes and its antioxidant and free radical scavenger effects.
 Keywords: Tagetes erecta L., Carbon Tetrachloride, Liver Damage, Hepato-protection

Berberine ameliorates CCl4‑induced liver injury in rats through regulation of the Nrf2‑Keap1‑ARE and p53 signaling pathways.

Berberine (BBR) is an isoquinoline alkaloid, reported to have multiple pharmacological functions. However, its effects against CCl4-induced oxidative damage remain poorly studied. Therefore, the present study investigated the protective action of BBR, and its antioxidant mechanisms, against CCl4-induced liver injury in rats. A total of 48 rats were randomly arranged into six groups: Control; model; positive control (PC); BBR low-dose (BL); BBR middle-dose (BM); and BBR high-dose (BH). The BL, BM and BH animals received BBR (5, 10 and 15 mg/kg by weight, respectively) orally for 7 consecutive days. Rats in the PC group were given silymarin (150 mg/kg), and the control and model groups were administered distilled water orally. At the end of the experiment, blood samples and livers were collected. To measure the liver biochemical indices, the reactive oxygen species (ROS) generation and the expression levels of related genes and protein, the following methods were used: An automatic biochemical analyzer; flow cytometry; spectrophotometry; reverse transcription-quantitative PCR; western blotting; and hematoxylin and eosin staining. The results revealed that BBR significantly decreased the serum levels of alanine transaminase, aspartate transaminase and alkaline phosphatase, and increased those of glutathione and superoxide dismutase, but decreased malondialdehyde activity in hepatic tissue, and significantly decreased the reactive oxygen species level in hepatocytes. In hepatic tissue, the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), kelch-like ECH-associated protein 1 (Keap-1), NAD(P)H quinone dehydrogenase 1 (NQO-1), heme oxygenase 1 (HO-1), Bcl-2 and Bcl-xL mRNA, and HO-1 protein were elevated, and the expression of p53 mRNA was decreased, particularly in the BH group (15 mg/kg). In conclusion, BBR exerts a protective action against CCl4-induced acute liver injury in rats via effectively regulating the expression of Nrf2-Keap1-antioxidant responsive element-related genes and proteins, and inhibiting p53 pathway-mediated hepatocyte apoptosis.

Hepatoprotective properties from the seaweed Bryothamnion triquetrum (S.G.Gmelin) M.A.Howe against CCl4-induced oxidative damage in rats

Context: Seaweeds are seen as a traditional food and folk medicine by different coastal countries. The red seaweed Bryothamnion triquetrum is a widely distributed species that grows in shallow waters, and different authors have demonstrated a possible application of the seaweeds as a source of natural antioxidants and relative diseases. Aims: To evaluate the hepatoprotective properties on CCl4-induced oxidative stress in rats that were associated with the antioxidant activity from the polyphenol-rich fractions of the red seaweed Bryothamnion triquetrum. Methods: Polyphenols were determined by Folin-Cioacalteu. Antioxidant activity from phenolic compounds-rich fractions was measured by different assays (DPPH, Reducing power, β-Carotene/linoleic acid assay and Inhibition of lipoperoxidation). Aqueous extract from B. triquetrum was administered during 20 days to rats and submitted CCl4-Induced oxidative damage. The peroxidation and hepatic damage (TBARS, ASAT and ALAT), antioxidant metabolite and enzymes (glutathione, catalase and superoxide dismutase) were evaluated. Also, it was evaluated the expression of antioxidant enzymes by RT-PCR. Results: The antioxidant activity determined by different assays with polyphenolic fractions. Free Phenolic Acid was more active: DPPH, 20 µg 87%; Reducing power OD = 0.490, 20 µg ; β-carotene/linoleic acid 1 µg 53%, and inhibition of lipid peroxidation 0.250 µg 100%. Rats treated displayed lower liver TBARS, ASAT and ALAT than CCl4-treated group and catalase activity was increased. It was demonstrated expression of catalase. Conclusions: Data suggest that Bryothamnion triquetrum protects the liver against oxidative stress by modulating its antioxidant enzymes and oxidative status with potential use as phytodrug or functional food.

Essential oil from halophyte Lobularia maritima: protective effects against CCl4-induced hepatic oxidative damage in rats and inhibition of the production of proinflammatory gene expression by lipopolysaccharide-stimulated RAW 264.7 macrophages.

The present study evaluates the chemical profiling of the essential oil of a halophyte, L. maritima (LmEO), and its protective potential against CCl4-induced oxidative stress in rats. Forty compounds have been identified in LmEO. The major components are α-pinene (3.51%), benzyl alcohol (8.65%), linalool (22.43%), pulegone (3.33%), 1-phenyl butanone (7.33%), globulol (4.32%), γ-terpinene (6.15%), terpinen-4-ol (4.31%), α-terpineol (3.9%), ledol (3.59%), epi-α-cadinol (3.05%) and α-cadinol (4.91%). In comparison with the CCl4-intoxicated group, LmEO treatment resulted in decreased liver serum marker enzymes, decreased lipid peroxidation and increased antioxidant enzyme levels, with overall further amelioration of oxidative stress. The administration of LmEO to CCl4-treated rats at a dose of 250 mg kg−1 body weight significantly reduced the toxic effects and the oxidative stress on the liver, thus validating the traditional medicinal claim of this plant. Moreover, the anti-inflammatory activity of LmEO was evaluated in lipopolysaccharide-stimulated murine RAW 264.7 cells. Our oil could modulate the inflammatory mode of the macrophages by causing reduction in iNOS and COX2 enzymes as well as in IL-1β, IL-6, and TNF-α cytokine levels. These findings suggest that LmEO exerts anti-inflammatory effects by regulating the expression of inflammatory cytokines.

Chemical characteristics, antioxidant capacities and hepatoprotection of polysaccharides from pomegranate peel

This proposed work aimed to investigate the chemical characteristic, antioxidant capacities and hepatoprotection effect of pomegranate peel polysaccharides (PPP) on CCl4-induced oxidative damage in mice. PPP was identified as the acidic heteropolysaccharides by HPLC methods. In vitro test showed that PPP had excellent reducing power and scavenging effects against free radicals. Administration of PPP (50, 100 and 200 mg/kg·bw) in mice before the injection of CCl4 could observably antagonize the increased serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and hepatic malonaldehyde level in CCl4-induced mice, especially administrated with 200 mg/kg·bw of PPP. Hepatic enzymatic activities of total superoxide dismutase, glutathione peroxidase, catalase and non-enzymatic activity of glutathione were markedly increased at high dosage of PPP, respectively. In addition, histopathological observation of liver further proved these biochemical characteristics. Therefore, it can be concluded that PPP exhibits strong protective effects against CCl4-induced liver injury in mice.

Caffeic acid rich Citrus macroptera peel powder supplementation prevented oxidative stress, fibrosis and hepatic damage in CCl4 treated rats

BackgroundCitrus macroptera has been used as a culinary fruit and medicinal plant in traditional medicine system in Bangladesh. The aim of the present study was to evaluate the presence of phenolic compounds in Citrus macroptera peel powder and the protective effect of Citrus macroptera against carbon tetrachloride (CCl4)-induced liver injury in rats.MethodsThe hepatoprotective activity was assessed using various biochemical parameters such as liver marker enzymes (alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP)) and oxidative stress parameters. Histopathological changes in the liver of different groups were also studied.ResultsAdministration of CCl4 increased the serum ALT, AST, ALP enzymatic activities and lipid peroxidation products but decreased the cellular antioxidant activities and reduced glutathione (GSH) levels in rats which were brought back to near normal levels by the treatment with Citrus macroptera. Citrus macroptera administration has also shown to decrease the necrotic zones, fibrosis and inflammatory cell infiltration in CCl4 treated rats. HPLC-DAD analysis of Citrus macroptera extract showed the great presence of caffeic acid and (−) epicatechin.ConclusionThe results of this study suggest that Citrus macroptera exerts hepatoprotective activity via promoting the antioxidant defense against CCl4-induced oxidative liver damage.

Phytochemical and cytotoxic evaluation of Medicago monantha: In vivo protective potential in rats

This research focuses on screening and evaluation of bioactive constituents in plants through pharmacological assays. In present study, we evaluated phytochemicals, cytotoxic activity, in vivo effect of M. monantha against CCl4 induced toxicity in cardiac and renal tissues and its aphrodisiac potential in rats. Shade dried plant was extracted with methanol. The phytochemical screening indicates the presence of flavonoids and alkaloids. Aphrodisiac study showed improved sexual desire; may be attributed to the presence of saponins that boosts the androgen level. Cytotoxicity of the plant was assessed through brine shrimp lethality assay and nearly all the fractions showed promising results. The in vivo study focused on the protective ability of extract against CCl4-induced oxidative damage in renal and cardiac tissues of rats. Serum analysis revealed that CCl4 intoxication increased the levels of bilirubin and blood urea nitrogen (BUN). Antioxidant enzyme analysis showed that catalase, peroxidase, superoxide dismutase, glutathione-S-transferase, glutathione activity and protein levels declined due to CCl4 induced renal and cardiac toxicity. Moreover, the histopathological studies of both low & high dose plant treated group’s revealed glomerular hypertrophy and glomerular congestion in kidney, cardiac degeneration and vacuolization of germinal epithelium induced by CCl4 intoxication. DNA also shows damage showed the toxic nature of the plant.

Pre- vs. post-treatment with melatonin in CCl4-induced liver damage: Oxidative stress inferred from biochemical and pathohistological studies

AimsThe present study was designed to compare the ameliorating potential of pre- and post-treatments with melatonin, a potent natural antioxidant, in the carbon tetrachloride-induced rat liver damage model by tracking changes in enzymatic and non-enzymatic liver tissue defense parameters, as well as in the occurring pathohistological changes. Main methodsRats from two experimental groups were treated with melatonin before and after CCl4 administration, while the controls, negative and positive, received vehicle/melatonin and CCl4, respectively. Serum levels of transaminases, alkaline phosphates, γ-GT, bilirubin, and albumin, as well as a wide panel of oxidative stress-related parameters in liver tissue, were determined in all experimental animals. Liver tissue specimens were stained with hematoxylin and eosin and further evaluated for morphological changes. Key findingsBoth pre- and post-treatment with melatonin prevented a CCl4-induced increase in serum (ALT, AST, and γ-GT) and tissue (MDA and XO) liver damage markers and a decrease in the tissue total antioxidant capacity, in both enzymatic and non-enzymatic systems. The intensity of pathological changes, hepatocyte vacuolar degeneration, necrosis and inflammatory cell infiltration, was suppressed by the treatment with melatonin. SignificanceIn conclusion, melatonin, especially as a post-intoxication treatment, attenuated CCl4-induced liver oxidative damage, increased liver antioxidant capacities and improved liver microscopic appearance. The results are of interest due to the great protective potential of melatonin that was even demonstrated to be stronger if applied after the tissue damage.