(Z)2-(5-(4-methoxybenzylidene)-2, 4-dioxothiazolidin-3-yl) acetic acid protects rats from CCl(4) -induced liver injury

Background and Aim: (Z)2‐(5‐(4‐methoxybenzylidene)‐2, 4‐dioxothiazolidin‐3‐yl) acetic acid (MDA) is an aldose reductase (AR) inhibitor. Recent studies suggest that AR contributes to the pathogenesis of inflammation by affecting the nuclear factor κB (NF‐κB)‐dependent expression of cytokines and chemokines and therefore could be a novel therapeutic target for inflammatory pathology. The current study evaluated the in vivo role of MDA in protecting the liver against injury and fibrogenesis caused by CCl₄ in rats, and the underlying mechanisms. Methods: A single injection of CCl₄ induced acute hepatitis, and repeated injections were used to induce hepatic fibrosis in rats. Therapeutic efficacy was assessed by comparison of the severity of hepatic injury and fibrosis in MDA ‐ treated rats versus untreated controls. Results: MDA significantly protected the liver from injury by reducing the activity of serum alanine aminotransferase, and improving the histological architecture of the liver. MDA modulated NF‐κB‐dependent activation of inflammatory cytokines by reducing hepatic mRNA levels of tumor necrosis factor‐α, interleukin‐1β, inducible nitric oxide (NO) synthase and transforming growth factor‐β. In addition, MDA attenuated oxidative stress by increasing the content of hepatic glutathione. These favorable changes were associated with suppressed hepatic NF‐κB activation by MDA. MDA treatment improved liver fibrosis in rats that received repeated CCl₄ injections. In vitro, MDA attenuated phosphorylation of IκB and activation of NF‐κB, and thus prevented biosynthesis of NO in lipopolysaccharide‐activated RAW264.7 cells. Conclusions: The present study suggests that AR is a novel therapeutic anti‐inflammatory target for the treatment of hepatitis and liver fibrosis.     

Hepatoprotective effect of the selective mineralocorticoid receptor antagonist, eplerenone against carbon tetrachloride-induced liver injury in rats

Background. Eplerenone is a selective mineralocorticoid receptor (MR) antagonist, and its potential protective role in cardiovascular injury has been reported by several studies. However, whether and how this drug can ameliorate hepatic injury in rats is unknown.Material and methods. The present study was conducted to investigate effect of eplerenone against liver injury induced by carbon tetrachloride (CCl₄) in rats. The biochemical liver function tests and oxidative stress parameters including malondialdehyde (MDA), reactive oxygen species (ROS), in addition to the reduced glutathione (GSH) levels were evaluated. Moreover, serum tumor necrotic factors (TNF-α) level and histopathological changes were examined.Results. Our results show that pre-treatment with eplerenone (4 mg/kg per day for 4 weeks) revealed attenuation in serum activities of alanine aminotransferase (ALT), aspartate aminotransferase, (AST), alkaline phosphatase (ALP) and bilirubin levels that were enhanced by CCl₄. Further, pre-treatment with eplerenone inhibited the elevated hepatic MDA content and restored hepatic GSH to its normal level. The enhanced hepatic ROS production in CCl₄-treated group was markedly decreased by eplerenone administration. Eple-renone pre-treatment significantly attenuated the inflammatory responses caused by CCl₄ as evident by the decreased serum TNF-α level. Histopathological studies showed that eplerenone alleviated the liver damage and reduced the lesions caused by CCl₄.Conclusion. Collectively, the present study provides a proof to hepatoprotective actions of eplerenone via reducing oxidative stress and inflammatory responses in CCl₄-induced liver damage in rat model.     

Melatonin promotes hepatic differentiation of human dental pulp stem cells: clinical implications for the prevention of liver fibrosis

Melatonin's effect on hepatic differentiation of stem cells remains unclear. The aim of this study was to investigate the action of melatonin on hepatic differentiation as well as its related signaling pathways of human dental pulp stem cells (hDPSCs) and to examine the therapeutic effects of a combination of melatonin and hDPSC transplantation on carbon tetrachloride (CCl₄)‐induced liver fibrosis in mice. In vitro hepatic differentiation was assessed by periodic acid‐Schiff (PAS) staining and mRNA expression for hepatocyte markers. Liver fibrosis model was established by injecting 0.5 mL/kg CCl₄ followed by treatment with melatonin (5 mg/kg, twice a week) and hDPSCs. In vivo therapeutic effects were evaluated by histopathology and by means of liver function tests including measurement of alanine transaminase (ALT), aspartate transaminase (AST), and ammonia levels. Melatonin promoted hepatic differentiation based on mRNA expression of differentiation markers and PAS‐stained glycogen‐laden cells. In addition, melatonin increased bone morphogenic protein (BMP)‐2 expression and Smad1/5/8 phosphorylation, which was blocked by the BMP antagonist noggin. Furthermore, melatonin activated p38, extracellular signal‐regulated kinase (ERK), and nuclear factor‐κB (NF‐κB) in hDPSCs. Melatonin‐induced hepatic differentiation was attenuated by inhibitors of BMP, p38, ERK, and NF‐κB. Compared to treatment of CCl₄‐injured mice with either melatonin or hDPSC transplantation alone, the combination of melatonin and hDPSC significantly suppressed liver fibrosis and restored ALT, AST, and ammonia levels. For the first time, this study demonstrates that melatonin promotes hepatic differentiation of hDPSCs by modulating the BMP, p38, ERK, and NF‐κB pathway. Combined treatment of grafted hDPSCs and melatonin could be a viable approach for the treatment of liver cirrhosis.     

Antioxidant,hepatoprotective and hypolipidemic effects of methanolic root extract of Cassia singueana in rats following acute and chronic carbon tetrachloride intoxication

ObjectiveTo evaluate in vivo antioxidant and hepatoprotective activities of the methanolic extract of the root of Cassia singueana in rats following acute and chronic carbon tetrachloride intoxication.MethodsMalondialdehyde (MDA), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin as indices of liver damage and lipid peroxidation were detected in rats after intraperitoneal administration of extract (5 mg/kg).ResultsThe liver, kidney and heart showed significant reduction (P<0.05) in the levels of MDA from (0.18±0.04), (0.23±0.07) and (0.26±0.10) nmol/mg respectively in the CCl₄ control to (0.15±0.03), (0.17±0.04) and (0.17±0.07) nmol/mg protein in groups pre-treated with the extract for three days at 5 mg/kg). Similarly, compared to the CCl₄ control, significant reduction (P<0.05) in serum AST, ALT and bilirubin as well as in level of total cholesterol and MDA with concomitant increase in HDL cholesterol, superoxide dismutase and catalase levels when CCl₄-intoxicated rats were treated with Cassia singueana root extract for two weeks.ConclusionsThese results suggest that methanolic extract of Cassia singueana contain potent antioxidant compounds that can offer significant protection against hepatic and oxidative injuries.     

The protective effects of n-acetylcysteine against acute hepatotoxicity

Objectives

N-acetylcysteine (NAC) increases tissue levels of glutathione and has been widely investigated as a protective and antioxidative agent. This study evaluated the protective effect of NAC on under carbon tetrachloride (CCl₄)-induced acute liver injury in the rat.

Methods

Three-month-old Sprague–Dawley rats were intraperitoneally administered 4 mL/kg CCl₄ (1:1 dissolved in olive oil, group 1) or 4 mL/kg CCl₄?+?NAC 150 mg/kg, 3 and 6 h after CCL₄ (group 2) or 4 mL/kg olive oil (group 3, control). Twenty-four hours after administering CCl₄, all of the rats were sacrificed. Biochemical assessment of serum transaminases and malonaldehyde (MDA) and tissue MDA, myeloperoxidase (MPO), and nitric oxide was done. Histopathological assessments were performed.

Results

Serum transaminases and tissue and serum MDA and tissue MPO were all increased in group 1 compared to control and were significantly decreased in the group treated with NAC. Histopathological comparison of the groups showed a decrease in congestion, polymorphonuclear leukocytes, mononuclear leukocytes, vacuolar degeneration of hepatocyte, and hepatocellular necrosis in the group treated with NAC.

Conclusion

Our results suggest that NAC prevents experimental acute hepatic failure by preventing oxidative stress.     

Effects of salviainolic acid A (SA‐A) on liver injury: SA‐A action on hepatic peroxidation

Abstract: Background/Aims: This study aimed to investigate the actions of salviainolic acid A (SA‐A), an antiperoxidative component of Salvia miltiorrhiza (Sm), on rat liver injury and fibrosis. Methods: Acute and chronic rat liver injury models were established using carbon tetrachloride (CCl₄). After 48 h (acute) or during 6 weeks of CCl₄ injection, rats were further divided and treated with biphenyl dimethyl‐dicarboxylate (BDD) or colchicine, as a control antifibrotic treatment, with Sm, a herbal compound, or SA‐A, a water‐soluble extract of Sm. Liver function was investigated by assessing alanine transaminase (ALT) and aspartate transaminase (AST) activities, histological analysis, hydroxyproline (Hyp) and malondiadehyde (MDA) content. In vitro, isolated cultured hepatocytes were injured with CCl₄ gas for 24 h, followed by treatment with either vitamin E or various concentrations of SA‐A. The extent of hepatocyte injury was monitored by analyzing various lipid peroxidative parameters such as superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), lactase dehydrogenase (LDH), and glutathione peroxidase (GSH‐PX) levels in hepatocyte supernatants. Results: SA‐A significantly decreased abnormal serum ALT activity both in acutely and chronically injured rat livers, decreased abnormal serum AST activity, Hyp and MDA content and attenuated hepatic collagen deposition. After CCl₄ incubation and injury, the activities of AST, ALT CAT, GSH‐PX and LDH and MDA content in hepatocyte supernatants increased significantly, but GSH levels decreased significantly. SA‐A markedly improved these pathological changes in a dose‐dependent manner. 10^?4 mol/l SA‐A had stronger inhibitory action than vitamin E. Conclusions: Our studies suggest that SA‐A has antiperoxidative effects on injured hepatocytes in liver injury and fibrosis induced by CCl₄.     

Hepatoprotective and antioxidant activity of methanolic extract of flowers of Nerium oleander against CCl4-induced liver injury in rats

ObjectiveTo investigate the antioxidant and hepatoprotective activity of methanolic flower extract of Nerium oleander against CCl₄-induced hepatotoxicity in rats.MethodsIn vitro antioxidant activity of methanolic extract of flowers of Nerium oleander (MENO–F) was evaluated by various assays, including reducing power, lipid peroxidation, DPPH, ABTS, superoxide anion, hydroxyl radicals and metal chelation. The hepatoprotective and in vivo antioxidant activity of MENO-F were evaluated against CCl₄–induced hepatic damage in rats. The MENO-F at dose of 100, 200 and 400 mg/kg were administered orally once daily for seven days. Serum enzymatic levels of serum glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), serum alkaline phosphatase (ALP) and total bilirubin were estimated along with estimation of superoxide dismutase (SOD) and malondialdehyde (MDA) levels in liver tissues. Further histopathological examination of the liver sections was carried out to support the induction of hepatotoxicity and hepatoprotective efficacy.ResultsThe extract showed potent activities on reducing power, lipid peroxide, DPPH, ABTS, superoxide anion, hydroxyl radical and metal chelation. The substantially elevated serum enzymatic levels of AST, ALT, ALP and total bilirubin were found to be restored towards normalization significantly by the MENO-F in a dose dependent manner with maximum hepatoprotection at 400 mg/kg dose level. The histopathological observations supported the biochemical evidences of hepatoprotection. Elevated level of SOD and decreased level of MDA further strengthen the hepatoprotective observations.ConclusionsThe results of the present study strongly reveal that MENO-F has potent antioxidant activity and hepatoprotective activity against CCl₄-induced hepatic damage in experimental animals.     

Effects of 1‐O‐hexyl‐2,3,5‐trimethylhydroquinone on carbon tetrachloride‐induced hepatic cirrhosis in rats

Aim: The present study was undertaken to evaluate the effects of 1‐O‐hexyl‐2,3,5‐trimethylhydroquinone (HTHQ), a synthesized vitamin E derivative, on carbon tetrachloride (CCl₄)‐induced cirrhosis. Methods: Rats were treated with hypodermic injections of CCl₄ twice a week to induce the hepatic cirrhosis, and given drinking water containing HTHQ or solvent. Primary cultures of rat hepatocytes were performed to evaluate the effects of HTHQ on the expression of inducible nitric oxide synthase (iNOS). Results: Masson's staining of rat livers showed fibrosis around pseudo‐lobules in the CCl₄ group, the lesions being reduced in the CCl₄ HTHQ group. Increases in liver tissue hydroxyproline and α₁(I) collagen, α‐smooth muscle actin and iNOS induced by CCl₄, were also markedly diminished by HTHQ. Furthermore, both HTHQ and vitamin E attenuated interleukin‐1β‐induced iNOS protein expression in cultured hepatocytes, the potency of HTHQ being 10‐times higher than that of vitamin E. Conclusion: HTHQ may inhibit development of hepatic cirrhosis in rats, more potently than vitamin E, by inhibiting the iNOS expression in hepatocytes. Because vitamin E has a radical scavenging action, roles of NO and peroxynitrite will be discussed in the effects of HTHQ on the fibrosis.     

Pharmacological aspects of N-acetyl-5-methoxytryptamine (melatonin) and 6-methoxy- 1,2,3,4-tetrahydro-β-carboline (pinoline) as antioxidants: Reduction of oxidative damage in brain region homogenates

Oxygen consumption is a necessity for all aerobic organisms, but oxygen is also a toxic molecule that leads to the generation of free radicals. The brain consumes a high percentage of the oxygen inhaled (18.5%), and it contains large amounts of unsaturated fatty acids, which makes it highly susceptible to lipid peroxidation. Melatonin (N-acetyl-5-methoxytryptamine), the main secretory product of the pineal gland, is a free radical scavenger that was found to protect against lipid peroxidation in many experimental models. Another compound found in the pineal gland is pinoline (6-methoxy-1,2,3,4-tetrahydro-beta-carboline). Pinoline is structurally related to melatonin. Evidence suggests that pinoline may have an antioxidant capacity similar to that of melatonin. In this study, the ability of pinoline to protect against H2O2-induced lipid peroxidation of different rat brain homogenates (frontal cortex, striatum, cerebellum, hippocampus, and hypothalamus) was investigated. The degree of lipid peroxidation was assessed by estimating the levels of thiobarbituric acid reactive substances, malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA). Pinoline's antioxidant capacity was compared with that of melatonin. Both melatonin and pinoline reduced the level of MDA and 4-HDA in a dose-dependent manner in all brain regions tested. To compare the antioxidant capacities, percent-inhibition curves were created, and the IC50 values were calculated. The IC50 values for melatonin were higher in all brain regions than were those for pinoline. The IC50 values for melatonin in the five different brain regions ranged from 0.16 mM-0.66 mM, and for pinoline, they ranged from 0.04 mM-0.13 mM. The possibility of synergistic interactions between melatonin and pinoline were also determined using the method of Berenbaum. Little evidence for either synergistic, additive, or antagonistic interactions between melatonin and pinoline was found.     

Restorative effect of Eclipta alba in CCl4 induced hepatotoxicity in male albino rats

ObjectiveTo elucidate the restorative effect of the aqueous leaf extract (85%) of the traditional medicinal plant Eclipta alba (E. alba) against CCl₄ induced hepatotoxicity in male albino rats.MethodsRestorative activity was assessed using CCl₄-induced hepatic injury in rats by monitoring biochemical parameters. Biochemical markers of hepatic damage such as aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) were assessed in serum. The oxidative stress was evaluated by measuring the levels of thiobarbutric acid reactive substance (TBARS), hydroperoxides, activity levels of enzymes viz. superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione-s-transferase (GST) in hepatic tissue.ResultsCCl₄ and olive oil mixture (1:1 dosage of 1 mL/kg b.w.) induced oxidative stress was indicated by elevated levels of TBARS and hydroperoxides, and augmented levels of serum AST, ALT and ALP. The depleted activity levels of antioxidant enzymes such as SOD, CAT, GPX and GST were found in CCl₄ induced animals. The aqueous leaf extract of E. alba (250 mg/kg b.w.) ameliorated the effects of CCl₄ and returned the alter levels of the biochemical markers near to the normal levels.ConclusionsThe study indicates that aqueous leaf extract of E. alba has potential restorative effect on CCl₄ induced hepatotoxicity in male albino rats.     

Efficacy evaluation of the protein isolated from Peganum harmala seeds as an antioxidant in liver of rats

ObjectiveTo evaluate the curative effect of the 132 KD protein isolated from the seeds of Peganum harmala (P. harmala) L. against carbon tetrachloride (CCl₄) induced oxidative stress in rats.MethodsAnimals were post treated intraperitoneally with 132 KD isolated protein at doses of 4 and 8 mg/kg body weight and bovine serum albumin (BSA) (8 mg/kg body weight) as well as vitamin C (250 mg/kg body weight p.o.) for 7 d after they challenged with CCl₄ orally (1 mL/kg body weight) in olive oil (50%) for 2 d.ResultsThe purified protein from seeds of P. harmala plant showed in vitro antioxidant activity with DPPH assay. Administration of CCl₄ induced induction in serum aminotransferases (AST, ALT), alkaline phosphatase (ALP), lipid profile parameters and liver malondialdehyde (MDA) and decrease in serum total protein, liver superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) levels. 132 KD protein treatment of rats post CCl₄ intoxication successfully alleviated the toxic effects of CCl₄.ConclusionsThe isolated protein possessed strong antioxidant activity comparable to that of BSA (negative control) and vitamin C (positive control).     

Overexpression of NK2 promotes liver fibrosis in carbon tetrachloride‐induced chronic liver injury

Background/Aims: Hepatocyte growth factor (HGF) inhibits liver fibrosis induced by carbon tetrachloride (CCl₄) in animal models. NK2 is a natural splice variant of HGF, but its in vivo function remains to be elucidated. We investigated the in vivo effects of NK2 on CCl₄‐induced liver fibrosis. Methods: NK2 transgenic mice and wild‐type (WT) mice were injected intraperitoneally with CCl₄ twice a week. The extent of hepatic fibrosis was evaluated by Azan–Mallory staining. Expression levels of mRNAs of transforming growth factor‐β1 (TGF‐β1) and matrix metalloproteinase‐13 (MMP‐13) were examined by real‐time polymerase chain reaction. The protein levels of α‐smooth muscle actin (α‐SMA), c‐Met and its phosphorylation were determined by Western blot analysis. Results: Liver fibrosis was significantly more severe in NK2 transgenic mice than in WT mice. CCl₄ administration increased the expression levels of TGF‐β1 mRNA and α‐SMA protein, and decreased the expression of MMP‐13 mRNA in livers of NK2 transgenic mice compared with those of WT mice. c‐Met protein expression in the liver was compatible with the degree of fibrosis. As for c‐Met activation, no difference was found between NK2 and WT livers. Conclusion: Overexpression of NK2 acts as an antagonist of HGF and promotes liver fibrosis in CCl₄‐induced chronic liver injury.     

N-methyl-4-isoleucine cyclosporine attenuates CCl -induced liver fibrosis in rats by interacting with cyclophilin B and D

Background and Aim: N‐methyl‐4‐isoleucine cyclosporine (NIM811), a new analogue of cyclosporine A, can inhibit collagen deposition in vitro and reduce liver necrosis in a bile‐duct‐ligation animal model. However, whether NIM811 effects on CCl₄‐induced rat liver fibrosis, and the related mechanism has not been determined. Methods: A liver fibrosis model was induced in Wistar rats using CCl₄ for 6 weeks. Meanwhile, two different doses of NIM811 (low‐dose 10 mg/kg and high‐dose 20 mg/kg) were given to the CCl₄‐treated rats. Liver fibrosis was then evaluated according to histopathological scoring and liver hydroxyproline content. Serum alanine aminotransferase, aspartate aminotransferase and albumin levels, expression of matrix metalloproteinase‐13, tissue inhibitor of metalloproteinase‐1, α‐smooth muscle actin and cyclophilin B and D in liver tissue were determined. Cyclophilin B and D were also studied in an hepatic stellate cell line. Results: Hydroxyproline content was decreased in both NIM811 groups compared with the model (P < 0.05). Liver necrosis and fibrosis were also attenuated in the NIM811 groups. NIM811 suppressed the expression of tissue inhibitor of metalloproteinase‐1, transforming growth factor beta mRNA and α‐smooth muscle actin protein in liver tissue. Expression of cyclophilin B in the fibrosis model was increased compared with the normal group (P < 0.05), and was decreased significantly in the low‐dose NIM811 treatment group (P < 0.05), which indicated that cyclophilin B might have a profibrotic effect. In vitro studies revealed that cyclophilin B and/or D knockout were associated with collagen inhibition. Conclusions: NIM811 attenuates liver fibrosis in a CCl₄‐induced rat liver fibrosis model, which may be related to binding with cyclophilin B and D.     

Protection of Regenerating Liver After Partial Hepatectomy from Carbon Tetrachloride Hepatotoxicity in Rats: Roles of Mitochondrial Uncoupling Protein 2 and ATP Stores

Uncoupling protein 2 (UCP₂), an inner mitochondrial membrane protein, can limit the generation of reactive oxygen species (ROS) and protect cells from injuries mediated by oxidative stress. We investigated the effect of upregulation of UCP₂ in the regenerating liver 96 h after 68% partial hepatectomy (PH) on the self-protection of regenerating liver against carbon tetrachloride (CCl₄) poisoning. Hepatotoxicity was induced in vivo by administering CCl₄ to rats that had undergone PH. After CCl₄ poisoning, the regenerating liver appeared to have less histological damage and lower serum alanine aminotransferase (ALT) levels. Lower malondialdehyde production and higher glutathione contents were also observed in the regenerating liver compared with the sham-operated liver after CCl₄ poisoning. UCP₂ expression was markedly elevated in the regenerating liver, and further increased after CCl₄ intoxication. Mitochondrial membrane potential and adenosine triphosphate stores maintained higher levels in the regenerating liver than in sham-operated liver after CCl₄ intoxication. The results showed that the regenerating liver exhibited a potent ability to resist CCl₄ intoxication, and the autoprotection of regenerating liver might result from reduction of ROS by UCP₂ and maintenance of higher ATP stores.     

The neuroprotective and anti‐apoptotic effects of melatonin on hemolytic hyperbilirubinemia‐induced oxidative brain damage

Melatonin exerts protection in several inflammatory and neurodegenerative disorders. To investigate the neuroprotective effects of melatonin in an experimental hemolysis‐induced hyperbilirubinemia, newborn Sprague–Dawley rats (25–40 g, n = 72) were injected with phenylhydrazine hydrochloride (PHZ; 75 mg/kg) and the injections were repeated at the 24th hour. Rats were treated with saline or melatonin (10 mg/kg) 30 min before the first and second PHZ injections and 24 h after the 2nd PHZ injections. Control rats (n = 24) were injected with saline, but not PHZ. At sixth hours after the last injections of saline or melatonin, all rats were decapitated. Tumor necrosis factor (TNF)‐α, IL–1β, IL‐10 and brain‐derived neurotrophic factor (BDNF) and S100B levels in the plasma were measured. Brain tissue malondialdehyde (MDA), glutathione (GSH) levels and myeloperoxidase (MPO) activities were measured, and brain tissues were evaluated for apoptosis by TUNEL method. In the saline‐treated PHZ group, hemoglobin, hematocrit levels were reduced, and total/direct bilirubin levels were elevated when compared to control group. Increased plasma TNF‐α, IL‐1β levels, along with decreased BDNF, S100B and IL‐10 values were observed in the saline‐treated PHZ group, while these changes were all reversed in the melatonin‐treated group. Increased MDA levels and MPO activities in the brain tissues of saline‐treated hyperbilirubinemic rats, concomitant with depleted brain GSH stores, were also reversed in the melatonin‐treated hyperbilirubinemic rats. Increased TUNEL(+) cells in the hippocampus of saline‐treated PHZ group were reduced by melatonin treatment. Melatonin exerts neuroprotective and anti‐apoptotic effects on the oxidative neuronal damage of the newborn rats with hemolysis and hyperbilirubinemia.     

Protective role of Juniperus phoenicea and Cupressus sempervirens against CCl(4)

AIM: To investigate the role of Cupressus sempervirens (C. sempervirens) and Juniperus phoenicea (J. phoenicea) extracts as therapeutic effect against CCl₄ with biochemical, histopathological evaluations.METHODS: A single intraperitoneal dose of 10% CCl₄ in olive oil (1 mL/kg body weight) was administered to a group of female Wister rats, sacrificed after 24 h (as the injury group). The other groups were given CCl₄ as described above and divided as follows: two groups of ten rats each were orally administered either J. phoenicea extract or C. sempervirens extract three times per week for six weeks and a further group administered CCl₄ was left for six weeks to allow self-recovery. At the end of experiment, the rats from all groups were sacrificed for sampling and for biochemical and histological analysis.RESULTS: Remarkable disturbances were observed in the levels of all tested parameters. On the other hand, rats injected with the toxic agent and left for one and a half month to self recover showed moderate improvements in the studied parameters while, treatment with both medicinal herbal extracts ameliorated the levels of the disturbed biochemical parameters. The group treated with J. phoenicea extract showed a remarkable improvement in comparison to the CCl₄ treated group. The C. sempervirens group revealing an even more remarkable effect showing histopathological liver& kidney profiles close to those of the control group.CONCLUSION: C. sempervirens and J. phoenicea leaf extracts show a remarkable effect in enhancing liver and kidney functions and may thus be of therapeutic potential in treatment hepatotoxicity and nephrotoxicity.     

Effect of human umbilical cord blood‐derived mesenchymal stem cells in a cirrhotic rat model

Background/Aim: Cirrhosis is a long‐term consequence of chronic hepatic injury and no effective therapy is currently available for this disease. Recent reports have shown that the mesenchymal stem cells (MSCs) have the capacity to differentiate into hepatocytes, and umbilical cord blood is a rich source of MSCs. Hence, we investigated the effect of infusing of human umbilical cord blood‐derived MSCs (HMSCs) in carbon tetrachloride (CCl₄)‐induced cirrhosis in a rat model. Methods: The effect of HMSCs on cirrhosis was evaluated using haematoxylin and eosin and Masson's trichrome staining. To evaluate cirrhosis‐related factors, we measured protein and mRNA expression of transforming growth factor β₁ (TGF‐β₁), collagen type I and α‐smooth muscle actin (α‐SMA). Results: Histological findings showed that liver fibrosis in rats was alleviated by HMSCs infusion. Interestingly, CM‐DiI‐labelled HMSCs expressed the hepatocyte‐specific markers, human albumin and α‐fetoprotein. Infusion of HMSCs significantly inhibited TGF‐β₁, collagen type I and α‐SMA expressions in CCl₄‐induced cirrhotic rats. Conclusion: Our results showed that HMSCs infusion could improve liver fibrosis in rats with CCl₄‐induced cirrhosis, raising the possibility for clinical use of HMSCs in the treatment of cirrhosis.     

Therapeutic value of melatonin in an experimental model of liver injury and regeneration

Melatonin has marked antioxidant properties. The aim of the present study was to evaluate the therapeutic effect of melatonin on acute liver injury induced in rats by carbon tetrachloride (CCl4), allyl alcohol (AA) and their combination. A total of 108 male Wistar rats were divided into 12 experimental groups according to their treatment regimen (n = 5-10 rats in each group). Melatonin (100 mg/kg body weight, BW) was administered 6 hr (a) after a single dose of CCl4 (intragastrically 0. 66 mL/kg BW diluted 1:1 v/v with corn oil); (b) a single dose of AA (intraperitonealy, 0.62 mmol/kg BW 1:50 v/v in 0.9% saline solution); and (c) a combination of the above substances. Rats were sacrificed at 24 and 48 hr post-toxin administration and the therapeutic effect of melatonin was investigated by assessment of histopathological changes and lipid peroxidation alterations determined by measuring tissue malondialdehyde plus 4-hydroxy-nonenal (MDA + 4-HNE), plasma MDA and plasma levels of liver enzymes. The levels of a key antioxidant, glutathione (GSH), were measured in liver tissue homogenates. Hepatic necrosis was significantly reduced in the melatonin-treated rats 48 hr after administration of CCl4, AA and CCl4 + AA. The levels of hepatic enzymes in plasma were found to be significantly reduced at 24 and 48 hr in the CCl4 + AA treated rats after melatonin administration. Additionally, MDA and MDA + 4-HNE concentrations were significantly reduced at 24 and 48 hr time-points in all groups that received melatonin. GSH levels were decreased in liver after the toxic substances administration, whereas melatonin reversed this effect. In conclusion, a single dose of melatonin decreased hepatic injury induced by CCl4, AA and CCl4 + AA. The inhibition of the oxidative stress and therefore lipid peroxidation by melatonin in CCl4 and AA administered animals, may constitute the protective mechanism of melatonin against acute liver injury.