Attenuating effect of Ginkgo biloba leaves extract on liver fibrosis induced by thioacetamide in mice

The interplay of p38 MAPK signaling and mitochondrial metabolism, a dynamic target in cancer and pathological contexts

Mitochondria play a crucial role in cellular metabolism and bioenergetics, orchestrating various cellular processes, including energy production, metabolism, adaptation to stress, and redox balance. Besides, mitochondria regulate cellular metabolic homeostasis through coordination with multiple signaling pathways. Importantly, the p38 mitogen-activated protein kinase (MAPK) signaling pathway is a key player in the intricate communication with mitochondria, influencing various functions. This review explores the multifaced interaction between the mitochondria and p38 MAPK signaling and the consequent impact on metabolic alterations. Overall, the p38 MAPK pathway governs the activities of key mitochondrial proteins, which are involved in mitochondrial biogenesis, oxidative phosphorylation, thermogenesis, and iron homeostasis. Additionally, p38 MAPK contributes to the regulation of mitochondrial responses to oxidative stress and apoptosis induced by cancer therapies or natural substances by coordinating with other pathways responsible for energy homeostasis. Therefore, dysregulation of these interconnected pathways can lead to various pathologies characterized by aberrant metabolism. Consequently, gaining a deeper understanding of the interaction between mitochondria and the p38 MAPK pathway and their implications presents exciting forecasts for novel therapeutic interventions in cancer and other disorders characterized by metabolic dysregulation.

Type-1 diabetes: Lessons from a decade of preclinical studies on phytotherapy

BACKGROUND

In recent decades, numerous herbal products have been shown to have antihyperglycemic and beta cell-regenerative effects in animal studies. However, there is no clinical evidence that those products completely cure patients with type-1 diabetes (T1D). Therefore, it seems that most of the phytochemicals do not have a significant impact on human beta cells, and the results of experimental studies conducted on them may not be generalizable to the clinic.

PURPOSE

The present work aims to review extensively the methods and results of preclinical studies on phytotherapy of T1D published in the last 10 years.

METHODS

This paper critically analyzes the designs of studies, treatment protocols, methods of diabetes induction, characteristics of the studied animals, clinical relevance, reproducibility of research, and other aspects related to conducting preclinical studies on T1D. We discussed limitations that make many of the results of these studies not generalizable to the clinic. Finally, some recommendations were given to improve studies on the phytotherapy of T1D to avoid misleading interpretations about the antidiabetic effect of herbal compounds.

CONCLUSION

This paper can be considered a practical guide for researchers interested in the field of phytotherapy of T1D to increase the reliability, reproducibility, and validity of their preclinical studies.

Ginkgo biloba extract ameliorates skin fibrosis in a bleomycin-induced mouse model of systemic sclerosis

Systemic sclerosis (SSc) is a chronic autoimmune disease characterized by skin and internal organ fibrosis and obliterative vasculopathy. Few effective treatments are currently available for fibrosis in SSc, therefore, demand persists for novel therapies. Although use of Ginkgo biloba extract (GBE) has been reported to improve blood circulation and alleviate liver and lung fibrosis, its effect on skin fibrosis in SSc remains unclear. In this study, the effects and underlying mechanisms of GBE on skin fibrosis in bleomycin (BLM)-induced mouse model of SSc was investigated. GBE significantly reduced dermal thickness and protein levels of profibrotic factors in the BLM-induced SSc mouse model. Moreover, GBE inhibited the gene expression of profibrotic factors, such as COL1A1, α-SMA, and connective tissue growth factor (CTGF), in fibroblasts by suppressing transforming growth factor (TGF)-β signaling. Furthermore, GBE inhibited the transdifferentiation of adipocytes into myofibroblasts. Thus, our findings suggest that GBE is a promising therapeutic candidate for the treatment of SSc.

Study of the effect of bezafibrate with ginkgo biloba extracts in an animal model of hepatotoxicity induced by doxorubicin

This study aimed to evaluate the hepatoprotective effect of combining bezafibrate with ginkgo biloba in doxorubicin-induced hepatotoxicity in rats. Thirty Wister albino rats were allocated into five groups: The negative control group, the positive control group, both received 1 ml of D.W, bezafibrate group received (100 mg/kg), ginkgo biloba group received (60 mg/kg) and the fifth group received bezafibrate + ginkgo biloba. All the treatments were for 14 days along with doxorubicin on days 11-14 except for the negative control. Blood samples were used for the measurement of ALT, AST, ALP, total protein, total bilirubin, albumin, globulin, GSH, catalase, and IL-6. Liver tissue was sent for histopathological examination. The combination of ginkgo biloba and bezafibrate significantly decreased AST, ALP, AST/ALT ratio, albumin/globulin ratio, and IL-6 with significant elevations of catalase, and GSH. The combination group produced more hepatoprotection. This could be attributed to the additive anti-inflammatory and antioxidant effects of the combination.

Progress on traditional Chinese medicine in improving hepatic fibrosis through inhibiting oxidative stress

Hepatic fibrosis is a common pathological process that occurs in the development of various chronic liver diseases into cirrhosis and liver cancer, characterized by excessive deposition of the extracellular matrix. In the past, hepatic fibrosis was thought to be a static and irreversible pathological process. In recent years, with the rapid development of molecular biology and the continuous in-depth study of the liver at the microscopic level, more and more evidence has shown that hepatic fibrosis is a dynamic and reversible process. Therefore, it is particularly important to find an effective, simple, and inexpensive method for its prevention and treatment. Traditional Chinese medicine (TCM) occupies an important position in the treatment of hepatic fibrosis due to its advantages of low adverse reactions, low cost, and multi-target effectiveness. A large number of research results have shown that TCM monomers, single herbal extracts, and TCM formulas play important roles in the prevention and treatment of hepatic fibrosis. Oxidative stress (OS) is one of the key factors in the occurrence and development of hepatic fibrosis. Therefore, this article reviews the progress in the understanding of the mechanisms of TCM monomers, single herbal extracts, and TCM formulas in preventing and treating hepatic fibrosis by inhibiting OS in recent years, in order to provide a reference and basis for drug therapy of hepatic fibrosis.

Limonin relieves TGF-β-induced hepatocyte EMT and hepatic stellate cell activation in vitro and CCl4-induced liver fibrosis in mice via upregulating Smad7 and subsequent suppression of TGF-β/Smad cascade

Liver fibrosis is a pathological process as a result of intrahepatic deposition of excessive extracellular matrix. Epithelial-mesenchymal transition (EMT) of hepatocytes and activation of hepatic stellate cells (HSCs) both play important roles in the etiology of liver fibrosis. Here, we found that limonin repressed transforming growth factor-β1 (TGF-β)-induced EMT in AML-12 hepatocytes and activation of LX-2 HSCs. In both kinds of cells, limonin suppressed TGF-β-provoked Smad2/3 C-terminal phosphorylation and subsequent nuclear translocation. Transcription of Smad2/3-downstream genes was in turn reduced. However, limonin exerted few effects on Smad2/3 phosphorylation at linker region. Mechanistically, limonin increased Smad7 at mRNA level in both AML-12 and LX-2 cells. Knockdown of Smad7 abrogated inhibitory effects of limonin on TGF-β-induced EMT in AML-12 cells and activation of LX-2 cells. Further studies revealed that limonin alleviated mouse liver fibrosis induced by CCl₄. In livers of model mice, limonin upregulated Smad7 and declined C-terminal phosphorylation and nuclear translocation of Smad2/3. Transcription of Smad2/3-responsive genes was also attenuated. Our findings indicated that limonin inhibits TGF-β-induced EMT of hepatocytes and activation of HSCs in vitro and CCl₄-induced liver fibrosis in mice. Upregulated Smad7 which suppresses Smad2/3-dependent gene transcription is implicated in the hepatoprotective activity of limonin.

Improved hepatoprotective activity of Beta vulgaris L. leaf extract loaded self-nanoemulsifying drug delivery system (SNEDDS): in vitro and in vivo evaluation

OBJECTIVE

Beta vulgaris L. (beetroot) is a vegetable plant rich in phytochemical compounds such as phenolic acids, carotenoids and flavonoids. The objective of the current study is the development and optimization of self-nanoemulsifying drug delivery systems (SNEDDSs) to enhance the hepatoprotective activity of beet leaf (BL) extract.

METHODS

Total flavonoids content was estimated in the BL extract and its solubility was evaluated in various vehicles to select proper component combinations. Pseudo-ternary phase diagrams were constructed employing olive, linseed, castor and sesame oils (oil phase), Tween^® 20 (Tw20) and Tween^® 80 (Tw80) (surfactants (SAs)) as well as dimethyl sulfoxide (DMSO) and propylene glycol (PG) (co-surfactants (Co-SAs)). Optimization of formulations from the phase diagrams took place through testing their thermodynamic stability, dispersibility and robustness to dilution.

RESULTS

Four optimized BL-SNEDDS formulations, comprising linseed oil or olive oil, Tw80 and DMSO at two SA/Co-SA ratios (2:1 or 3:1) were chosen. They exhibited high cloud point and percentage transmittance values with spherical morphology of mean droplet sizes ranging from 14.67 to 16.06 nm and monodisperse distribution with negatively charged zeta potential < -9.51 mV. The in vitro release profiles of the optimized formulations in pH 1.2 and 6.8 were nearly similar, with a non-Fickian release mechanism. In vivo evaluation of BL-SNEDDSs hepatoprotective activity in a thioacetamide-induced hepatotoxicity rat model depicted promoted liver functions, inflammatory markers and histopathological findings, most prominently in the group treated by F7.

CONCLUSION

The results indicate that SNEDDS, as a nanocarrier system, has potential to improve the hepatoprotective activity of the BL extract.

Dunaliella salina microalgae oppose thioacetamide-induced hepatic fibrosis in rats

Several hepatic pathological conditions are correlated with the stimulation of hepatic stellate cells. This induces a cascade of events producing accretion of extracellular matrix components triggering fibrosis. Dunaliella salina, rich in carotenoids, was investigated for its potential antagonizing activity; functionally and structurally against thioacetamide (TAA) - induced hepatic fibrosis in rats. Adult male albino Wistar rats were treated with three dose levels of D. salina powder or extract (daily, p.o.); for 6 weeks, concomitantly with TAA injection. Serum levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), bilirubin and albumin were determined. Reduced glutathione (GSH), malondialdehyde (MDA), smooth muscle actin alpha (α-SMA) and collagen I hepatic contents were also estimated. Treatment with D. salina powder or extract caused a significant decline in serum levels of AST, ALT, ALP, bilirubin, MDA and hepatic contents of α-SMA and collagen I. Additionally, serum albumin and GSH hepatic content were highly elevated. Liver histopathological examination also indicated that D. salina reduced fibrosis, centrilobular necrosis, and inflammatory cell infiltration evoked by TAA. The results implied that D. salina exerts protective action against TAA-induced hepatic fibrosis in rats. The phytochemical investigation revealed high total carotenoid content prominently β-carotene (15.2 % of the algal extract) as well as unsaturated fatty acids as alpha-linolenic acid which accounts for the hepatoprotective activity.

The potential protective influence of flaxseed oil against renal toxicity induced by thioacetamide in rats

The present study was aimed to evaluate the influence of flaxseed oil on renal toxicity induced by thioacetamide in male rats. The animals were distributed into four groups. Rats of the first group were served as control. Rats of the second group were exposed to thioacetamide. Rats of the third group were treated with flaxseed oil and thioacetamide. Rats of the fourth group were treated with flaxseed oil. Significant increases of blood creatinine and uric acid were observed in TAA-treated rats after three weeks. In thioacetamide group, the levels of serum creatinine, blood urea nitrogen and uric acid were significantly elevated after six weeks. Histopathologically, the renal sections from thioacetamide-treated rats showed severe alterations in the structure of renal corpuscles including a degeneration of glomeruli and Bowman's capsules. Administration of flaxseed oil protects the observed biochemical and histopathological alterations induced by thioacetamide exposure. Hence, the results of this study suggest that flaxseed oil protects against thioacetamide-induced renal injury and the protective influence of flaxseed oil may be attributed to its antioxidant role.

Glibenclamide protects against thioacetamide-induced hepatic damage in Wistar rat: investigation on NLRP3, MMP-2, and stellate cell activation

Glibenclamide (GLB), most widely used in the treatment of type II diabetes mellitus, inhibits K+ATP channel in pancreatic-β cells and releases insulin, while thioacetamide (TAA) is a well-known hepatotoxicant and most recommended for the induction of acute and chronic liver disease. The purpose of this study was to evaluate the hepatoprotective potential of GLB against TAA-induced hepatic damage in Wistar rats. TAA (200 mg/kg, ip, twice weekly) and GLB (1.25, 2.5, and 5 mg/kg/day, po) were administered for 6 consecutive weeks. Different biochemical, DNA damage, histopathological, TEM, immunohistochemical, and western blotting parameters were evaluated. GLB treatment has no effects on the TAA-induced significant decrease in body and liver weights. TAA treatment significantly increased liver index and treatment with GLB has no effect the same. TAA treatment altered the liver morphology, whereas treatment with GLB normalized the alteration in morphology. Further, significant increase in oxidative stress, apoptosis, and DNA damage was found in TAA-treated animals and GLB treatment significantly reduced these effects. TAA-induced plasma transaminases and serum ALP levels were significantly restored by GLB. Furthermore, histopathological findings showed the presence of lymphocyte infiltration, collagen deposition, bridging fibrosis, degeneration of portal triad, and necrosis in TAA-treated animals and GLB intervention significantly reduced the same. TEM images revealed that GLB significantly normalized the hepatic stellate cell morphology as well as restored the number of lipid droplets. GLB treatment significantly downregulated the expressions of TGF-β1, α-SMA, NLRP3, ASC, caspase-1, and IL-1β, and upregulated MMP-2 and catalase against TAA-induced liver damage. The outcomes of the present study confirmed that GLB ameliorated the liver damage induced by TAA.

Ginkgo biloba extract (EGb761) did not express estrogenic activity in an immature rat uterotrophic assay

Ginkgo biloba is a dioecious tree that has been used in traditional Chinese medicine for about 5,000 years. In previous studies on ginkgo biloba extract (EGb761) using in vitro systems, we confirmed that EGb761 has biphasic effects on estrogenicity. In this study, we evaluated the agonistic and antagonistic activities of EGb761 using a uterotrophic assay in immature female rats. To evaluate agonistic and antagonistic effects of EGb761 on uterus, 21-day-old immature Sprague-Dawley (SD) female rats were treated with EGb761 (100, 200, or 400 mg/kg) by oral gavage, 10 μg/kg of estradiol (E2) or 1 mg/kg tamoxifen (TM) by subcutaneous injection, or with EGb761 plus E2 or TM for 3 consecutive days. At the end of the treatment period, animals were sacrificed and their body weights and organ weights (liver, lung, spleen and kidney) were measured. In addition, estrogen-related gene expressions (IGFBP-1 in liver and CaBP-9 in uterus) were determined. During the experiment, no animal showed clinical signs, a change in body weight or died. EGb761 treatment alone had no effect on absolute/relative uterine weight, luminal epithelial cell height (LECH, μm), or luminal circumference (LC, μm). In addition, uterine weights, LECHs, and LC induced by E2 or TM were not significantly changed by EGb761 at any dose. These results collectively suggested EGb761 has no agonistic/antagonistic effects in utero.

Preventive effects of total saponins of Panax japonicus on fatty liver fibrosis in mice

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a condition in which excess fat accumulates in the liver of a patient without a history of alcohol abuse. Fatty liver fibrosis, a severe form of NAFLD, is a key step which can be reversed by effective medical intervention. This paper aims to describe the protective role and mechanisms of action of total saponins of Panax japonicus (SPJ) against fatty liver fibrosis in mice. In this study, fatty liver fibrosis was induced by a high-fat (HF) diet combined with intraperitoneal injection of porcine serum.

MATERIAL AND METHODS

The fatty liver fibrosis model was induced by HF diet combined with intraperitoneal injection of porcine serum. The endoplasmic reticulum stress (ERS) response and C/EBP homologous protein (CHOP) and p-Jun N-terminal kinase (JNK)-mediated apoptosis and inflammation were assessed by serum biochemistry, hematoxylin-eosin (H + E), Masson and electronic microscopy staining, Hyp content detection, Western blotting and real time polymerase chain reaction (RT-PCR).

RESULTS

Saponins of Panax japonicus could significantly improve liver function and decrease the lipid level in the serum. The liver steatosis, collagen fibers and inflammatory cell infiltration were significantly improved in the SPJ group according to microscope observation. The RT-PCR analysis revealed that the collagen I (Coll), α smooth muscle actin (α-SMA), tissue inhibitors of MMPs (TIMP), CHOP and GRP78 mRNA expression levels were distinctly weakened by SPJ treatment; and western blotting analysis indicated that the phosphorylated JNK (p-JNK), Coll and 78 kD glucose-regulated protein (GRP78) protein expression levels were significantly alleviated, which might be associated with the inhibition of the ERS response and the CHOP and JNK-mediated apoptosis and inflammation pathway.

CONCLUSIONS

Based on this research, SPJ as a preventive medicine has great potential in prevention of liver fibrosis.

Caffeine intake decreases oxidative stress and inflammatory biomarkers in experimental liver diseases induced by thioacetamide: Biochemical and histological study

Liver disease remains a significant global health problem. Increased caffeine consumption has been associated with a lower prevalence of chronic liver disease. This study aimed to investigate the modifying effects of caffeine on liver injury induced by thioacetamide (TAA) administration in male rats and the possible underlying mechanisms. Forty adult male rats were equally classified into four groups: control group, received only tap water; caffeine-treated group, received caffeine (37.5 mg/kg per day); TAA-treated group, received intraperitoneal (i.p.) TAA (200 mg/kg b.w.) twice a week; and caffeine + TAA-treated group, received combined TAA and caffeine in the same previous doses. After eight weeks of treatment, blood samples were collected for biochemical analysis and liver specimens were prepared for histological and immunohistochemical studies and for assessment of oxidative stress. TAA induced liver toxicity with elevated liver enzymes and histological alterations, fatty changes, apoptosis, and fibrosis evidenced by increased immunohistochemical reaction to matrix metalloproteinase-9 (MMP-9) and collagen type IV in hepatocytes. Also, the levels of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) in serum were significantly elevated. Co-treatment with caffeine and TAA restored normal liver structure and function. Caffeine provided an anti-fibrogenic, anti-inflammatory, and antioxidant effect that was associated with recovery of hepatic histological and functional alterations from TAA-induced hepatotoxicity.

Silymarin Protects Mouse Liver and Kidney from Thioacetamide Induced Toxicity by Scavenging Reactive Oxygen Species and Activating PI3K-Akt Pathway

Silymarin (SMN) has been shown to possess a wide range of biological and pharmacological effects. Besides, SMN has antioxidant and free radical scavenging activities. Thioacetamide (TAA) is a well-documented liver toxin that requires oxidative bioactivation to elicit its hepatotoxic effect which ultimately modifies amine-lipids and proteins. Our study has been designed in a TAA exposed mouse model to investigate whether SMN could protect TAA-induced oxidative stress mediated hepatic and renal damage. Results suggest that TAA generated reactive oxygen species (ROS), caused oxidative stress and induced apoptosis in the liver and kidney cells via JNK as well as PKC and MAPKs signaling. All these detrimental effects of TAA could, however, be suppressed by SMN which not only scavenged ROS but also induced PI3K-Akt cell survival pathway in the liver and prevented apoptotic pathways in both the organs. Histological studies, collagen staining and DNA fragmentation analysis also supported our results. Combining, we say that SMN possess beneficial role against TAA mediated hepatic and renal pathophysiology.

Chemoprotective effect of omega-3 fatty acids on thioacetamide induced hepatic fibrosis in male rats

The current study was designed to investigate the possible protective effect of omega-3 fatty acids from fish oil on hepatic fibrosis induced by thioacetamide (TAA) in male rats. The experimental animals were divided into four groups. The first group was received saline solution and served as control. The second group was given 250 mg/kg body weight of TAA. The third group was treated with omega-3 fatty acids and TAA. The fourth group was given saline solution and supplemented with omega-3 fatty acids. Treatment of rats with TAA for three and six weeks resulted in a significant decrease in body weight gain, while the value of liver/body weight ratio was statistically increased. Furthermore, the levels of serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase and total bilirubin were significantly increased. After three weeks of exposure to only TAA, liver sections showed an abnormal morphology characterized by noticeable fibrosis with the extracellular matrix collagen contents and damage of liver cells’ structure. Liver sections from rats treated with only TAA for six weeks revealed an obvious increase in extracellular matrix collagen content and bridging fibrosis. Treating TAA-intoxicated rats with omega-3 fatty acids significantly attenuated the severe physiological and histopathological changes. Finally, the present investigation suggests that omega-3 fatty acids could act against hepatic fibrosis induced by TAA due to its antioxidant properties, thus supporting its use in hepatic fibrosis therapy.

Ginkgo biloba extract mitigates liver fibrosis and apoptosis by regulating p38 MAPK, NF-κB/IκBα, and Bcl-2/Bax signaling

Background

Liver fibrosis is the consequence of diverse liver injuries and can eventually develop into liver cirrhosis. Ginkgo biloba extract (GBE) is an extract from dried ginkgo leaves that has many pharmacological effects because of its various ingredients and has been shown to be hepatoprotective.

Purpose and methods

Aimed to investigate the underlying protective mechanisms of GBE on carbon tetrachloride (CCl₄)-induced liver fibrosis in rats. Male Sprague Dawley rats were randomly divided into four groups: control group (C), model group (M), low-dose group (L), and high-dose group (H). Liver fibrosis was induced by CCl₄ groups M, L, and H: group C was administered saline. In addition, GBE at different doses was used to treat groups L and H.

Results

The results of hematoxylin and eosin staining, Masson’s trichrome staining, a liver function index, and a liver fibrosis index showed that GBE application noticeably mitigated fibrosis and improved the function of the liver. The western blotting and immunohistochemistry analyses indicated that GBE reduced liver fibrosis not only by inhibiting p38 MAPK and NF-κBp65 via inhibition of IκBα degradation but also by inhibiting hepatocyte apoptosis via downregulation of Bax, upregulation of Bcl-2, and subsequent inhibition of caspase-3 activation. Inflammation-associated factors and hepatic stellate cell (HSC)-activation markers further demonstrated that GBE could effectively inhibit HSC activation and inflammation as a result of its regulation of p38 MAPK and nuclear factor-kappa B/IκBα signaling.

Conclusion

Our findings indicated a novel role for GBE in the treatment of liver fibrosis. The potential mechanisms may be associated with the following signaling pathways: 1) the p38 MAPK and nuclear factor-kappa B/IκBα signaling pathways (inhibiting inflammation and HSCs activation) and 2) the Bcl-2/Bax signaling pathway (inhibiting the apoptosis of hepatocytes).

Effect of Olea oleaster and Juniperus procera leaves extracts on thioacetamide induced hepatic cirrhosis in male albino mice

The effect of Olea oleaster and Juniperus procera leaves extracts and their combination on thioacetamide (TAA)-induced hepatic cirrhosis were investigated in male albino mice. One hundred sixty mice were used in this study and were randomly distributed into eight groups of 20 each. Mice of group 1 served as controls. Mice of group 2 were treated with TAA. Mice of group 3 were exposed to TAA and supplemented with O. oleaster leaves extracts. Mice of group 4 were treated with TAA and supplemented with J. procera leaves extracts. Mice of group 5 were subjected to TAA and supplemented with O. oleaster and J. procera leaves extracts. Mice of groups 6, 7 and 8 were supplemented with O. oleaster, J. procera, and O. oleaster and J. procera leaves extracts respectively. Administration of TAA for six and twelve weeks resulted in a decline in body weight gain and increased the levels of serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and total bilirubin. Histopathological evaluations of hepatic sections from mice treated with TAA showed severe alterations including increase of fibrogenesis processes with structural damage. Treatment of mice with these extracts showed a pronounced attenuation in TAA induced hepatic cirrhosis associated with physiological and histopathological alterations. Finally, this study suggests that the supplementation of these extracts may act as antioxidant agents and could be an excellent adjuvant support in the therapy of hepatic cirrhosis.

Pyrroloquinoline-quinone suppresses liver fibrogenesis in mice

Liver fibrosis represents the consequences of a sustained wound healing response to chronic liver injuries, and its progression toward cirrhosis is the major cause of liver-related morbidity and mortality worldwide. However, anti-fibrotic treatment remains an unconquered area for drug development. Accumulating evidence indicate that oxidative stress plays a critical role in liver fibrogenesis. In this study, we found that PQQ, a natural anti-oxidant present in a wide variety of human foods, exerted potent anti-fibrotic and ROS-scavenging activity in Balb/C mouse models of liver fibrosis. The antioxidant activity of PQQ was involved in the modulation of multiple steps during liver fibrogenesis, including chronic liver injury, hepatic inflammation, as well as activation of hepatic stellate cells and production of extracellular matrix. PQQ also suppressed the up-regulation of RACK1 in activated HSCs in vivo and in vitro. Our data suggest that PQQ suppresses oxidative stress and liver fibrogenesis in mice, and provide rationale for the clinical application of PQQ in the prevention and treatment of liver fibrosis.

Physiological investigations on the effect of olive and rosemary leaves extracts in male rats exposed to thioacetamide

Physiologically, it is known that thioacetamide (TAA) toxicity is generally associated with hepatic fibrosis induction, complicated metabolic disorders and health problems. The capability of extracts of olive and rosemary leaves to attenuate the severe physiological disturbances induced by thioacetamide (TAA) intoxication in male rats has been evaluated. Healthy male Wistar rats were used in the present study and were divided randomly into eight groups. Rats of the first group were served as normal control. Rats of the second group were administrated with TAA. Rats of the third, fourth and fifth groups were exposed to TAA plus olive leaves extract, TAA plus rosemary leaves extract and TAA plus olive and rosemary leaves extracts respectively. The sixth, seventh and eighth groups were supplemented with olive leaves extract, rosemary leaves extract, and olive and rosemary leaves extracts respectively. After 12 weeks of experimental treatments, the levels of serum glucose, total protein, albumin and high density lipoprotein cholesterol were significantly decreased, while the levels of triglycerides, cholesterol, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, creatine kinase and lactate dehydrogenase were statistically increased in rats exposed to TAA. Administration of the studied extracts inhibited the hematobiochemical parameters and improved the physiological disturbances induced by TAA intoxication. Additionally, most improvements were noted in rats administrated with rosemary leaves extract followed by olive and rosemary leaves extracts and olive leaves extract. These results suggested that the effect of these extracts might be due to their antioxidant activities against TAA toxicity.

Influence of olive and rosemary leaves extracts on chemically induced liver cirrhosis in male rats

The current study was undertaken to evaluate the protective activity of olive and rosemary leaves extracts on experimental liver cirrhosis induced by thioacetamide (TAA) in Wistar male rats. Highly significant decline in the values of body weight gain and highly statistically increase of liver/body weight ratio were noted in rats treated with TAA. Furthermore, the levels of serum alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase and total bilirubin were statistically increased. Additionally, light microscopic examination of liver sections from rats treated with TAA showed a marked increase in the extracellular matrix collagen content and bridging fibrosis was prominent. There were bundles of collagen surrounding the lobules that resulted in large fibrous septa and distorted tissue architecture. Interestingly, the findings of this experimental study indicated that the extracts of olive and rosemary leaves and their combination possess hepatoprotective properties against TAA-induced hepatic cirrhosis by inhibiting the physiological and histopathological alterations. Moreover, these results suggest that the hepatoprotective effects of these extracts may be attributed to their antioxidant activities.

Carvacrol ameliorates thioacetamide-induced hepatotoxicity by abrogation of oxidative stress, inflammation, and apoptosis in liver of Wistar rats

The present study was designed to investigate the protective effects of carvacrol against thioacetamide (TAA)-induced oxidative stress, inflammation and apoptosis in liver of Wistar rats. In this study, rats were subjected to concomitant prophylactic oral pretreatment of carvacrol (25 and 50 mg kg(-1) body weight (b.w.)) against the hepatotoxicity induced by intraperitoneal administration of TAA (300 mg kg(-1) b.w.). Efficacy of carvacrol against the hepatotoxicity was evaluated in terms of biochemical estimation of antioxidant enzyme activities, histopathological changes, and expressions of inflammation and apoptosis. Carvacrol pretreatment prevented deteriorative effects induced by TAA through a protective mechanism in a dose-dependent manner that involved reduction of oxidative stress, inflammation and apoptosis. We found that the protective effect of carvacrol pretreatment is mediated by its inhibitory effect on nuclear factor kappa B activation, Bax and Bcl-2 expression, as well as by restoration of histopathological changes against TAA administration. We may suggest that carvacrol efficiently ameliorates liver injury caused by TAA.