Protective effect of Curcuma longa L. extract on CCl4-induced acute hepatic stress

Protective effect of sinomenine against CCl4-induced acute liver injury through regulation of mitochondrial biogenesis

Carbon tetrachloride (CCl4)-provoked acute liver injury (ALI) is typified by intensified apoptotic, inflammatory, and oxidative changes besides mitochondrial dysfunction. Sinomenine is an active constituent in the medicinal plant Sinomenium acutum. The main objective of this study was to determine sinomenine-induced hepatoprotection following CCl4 challenge with an emphasis on unraveling the contribution of mitochondrial biogenesis-related factors. To induce ALI, CCl4 was injected i.p. and sinomenine was orally administered at 10, 25, and 50 mg/kg. Serum factors in relation to liver dysfunction were measured in addition to hepatic analysis of apoptotic, mitochondrial biogenesis, oxidative, and inflammatory parameters. Sinomenine pretreatment significantly lowered ALT and AST, MDA, IL-6, apoptosis intensity, and TNF-α and restored mitochondrial biogenesis besides enhancement of SOD, sirtuin-1, and AMPK. Sinomenine also conferred hepatoprotective impact, as was apparent by lower pathologic changes. These effects were accompanied by changes in gene expression for AMPK/sirtuin-1/PGC-1α/PPARγ. The current study showed sinomenine hepatoprotective impact in CCl4-induced ALI that is associated with its regulation of mitochondrial biogenesis and parallel enhancement of AMPK/sirtuin-1.

Screening of Multitarget Compounds against Acetaminophen Hepatic Toxicity Using In Silico, In Vitro, and In Vivo Approaches

Combination therapy and multitarget drugs have recently attracted much attention as promising tools to fight against many challenging diseases and, thus, represent a new research focus area. The aim of the current project was to screen multitarget compounds and to study their individual and combined effects on acetaminophen-induced liver injury. In this study, 2 of the best hepatoprotective multitargeting compounds were selected from a pool of 40 major compounds present in Curcuma longa and Cinnamomum zeylanicum by using molecular docking, ADMET profiling, and Pfizer's rule of five. The two selected compounds, quercetin and curcumin, showed a high binding affinity for the CYP2E1 enzyme, MAPK, and TLR4 receptors that contribute to liver injury. The candidates caused the decreased viability of cancer cell lines (HepG2 and Huh7) but showed no effect on a normal cell line (Vero). Examination of biochemical parameters (ALT, AST, ALP, and bilirubin) showed the hepatoprotective effect of the candidate drugs in comparison with the control group, which was confirmed by histological findings. Taken together, quercetin and curcumin not only satisfied the drug-like assessment criterion and proved to be multitargeting by preventing liver damage but also showed anticancer activities.

Turmeric extract (Curcuma longa L.) regulates hepatic toxicity in a single ethanol binge rat model

Hepatic alcohol clearance is a key factor to overcome alcohol hangovers, and over the period, alcohol hangovers may lead to inflammation and oxidative stress. Natural food products with high antioxidant and anti-inflammatory effects might contribute to hepatic alcohol clearance, a hypothesis in this study. The present study aimed to evaluate the influence of turmeric (Curcuma longa L., Zingiberaceae) is an herbal product having antioxidant and anti-inflammatory activities, on alcohol metabolism using binge alcohol drinking rat model. In vivo investigations revealed that pretreatment with turmeric extract enhanced alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activities upon binge ethanol (3 g/kg). Additionally, pretreatment with turmeric extract regulated CYP2E1 activity and levels of reactive oxygen species (ROS), Bax, Bcl-2, and inflammatory mediators like IL-1β, IL-6, and TNF-α. Moreover, turmeric extract upregulated superoxide dismutase, catalase, and glutathione peroxidase activities in liver tissues. Together, these observations shed light on the potential beneficial effects of turmeric extract against acute liver toxicity. The results offer an alternative natural functional food product, turmeric extract, to prevent the negative implications of binge drinking.

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.

Hura crepitans stem bark extract: A potential remedy to sub-acute liver damage

ETHNOPHARMACOLOGICAL SIGNIFICANCE AND AIM

Hura crepitans is commonly used to treat liver diseases in Nigeria and Ghana. Previous studies have supported its ethnomedicinal use in protecting the liver. The present study aimed at assessing the effect of H. crepitans stem bark on the subacute carbon tetrachloride (CCl₄)-induced liver damage in rats.

MATERIALS AND METHODS

The protective activities of ethanolic extract of H. crepitans stem bark was evaluated in CCl₄-induced subacute liver damage in rats (1:1 v/v in olive oil, intraperitoneally (i.p.), twice weekly for 8 weeks). Blood samples were obtained from the rats and used for some biochemical analysis such as liver function test (Aspartate transaminase, AST; Alanine aminotransferase, ALT; and Alkaline phosphatase, ALP), liver fibrotic indices (Aspartate platelet ratio index, APRI; AST/ALT and AST/PLT ratios) and oxidative stress markers (Malondialdehyde, MDA; Reduced glutathione, GSH; Glutathione S-transferase, GST; Glutathione peroxidase, GPx; and superoxide dismutase, SOD). Histopathological analyses were carried out to determine the expression of pro-inflammatory (NF-κB, COX-2, IL-17 and IL-23) using immunohistochemical techniques.

RESULTS

Oral administration of H. crepitans to CCl₄-induced hepatic injured rats significantly decreased oxidative stress, increased the levels of SOD, GSH, GST and GPx with reduced MDA levels. The plant also mitigated liver injury as evidenced in the significantly reduced levels of AST, ALT and ALP, while it inhibited the inflammatory process via the inhibition of NF-κB, and consequently down-regulateed the pro-inflammatory cytokines COX-2, IL-17 and IL-23, respectively. Biochemical observations were supported by improvement in liver microarchitecture.

CONCLUSION

The Hura crepitans demonstrated antioxidant, antiinflammatory and antifibrotic effect in hepatic injured rats. The study in a way justifies the traditional use of the plant for the treatment of subacute liver diseases in Nigerian Traditional medicine.

Medicinal plants with hepatoprotective potentials against carbon tetrachloride-induced toxicity: a review

Background

Carbon tetrachloride (CCl4) is a well-characterized hepatotoxic agent. With rising cases of liver diseases, the identification, assessment, and development of hepatoprotective agents from plants source has become imperative.

Main body

With arrays of literature on plants with hepatoprotective potentials, this review sourced published literatures between 1998 and 2020 and systematically highlighted about 92 medicinal plants that have been reported to protect against CCl4-induced liver injury in animal models. The results show that herbal plants provide protection for the liver against CCl4 by downregulation of the liver marker enzymes and activation of antioxidant capacity of the liver cells with the restoration of liver architecture. We also provided the traditional and accompanying pharmacological uses of the plants. A variety of phytochemicals mostly flavonoids and polyphenols compounds were suggested to offer protection against liver injuries.

Conclusion

It can be concluded that there are a variety of phytochemicals in plant products with hepatoprotective activity against CCl4-induced toxicity in animal models.

The Potential Application of Chinese Medicine in Liver Diseases: A New Opportunity

Liver diseases have been a common challenge for people all over the world, which threatens the quality of life and safety of hundreds of millions of patients. China is a major country with liver diseases. Metabolic associated fatty liver disease, hepatitis B virus and alcoholic liver disease are the three most common liver diseases in our country, and the number of patients with liver cancer is increasing. Therefore, finding effective drugs to treat liver disease has become an urgent task. Chinese medicine (CM) has the advantages of low cost, high safety, and various biological activities, which is an important factor for the prevention and treatment of liver diseases. This review systematically summarizes the potential of CM in the treatment of liver diseases, showing that CM can alleviate liver diseases by regulating lipid metabolism, bile acid metabolism, immune function, and gut microbiota, as well as exerting anti-liver injury, anti-oxidation, and anti-hepatitis virus effects. Among them, Keap1/Nrf2, TGF-β/SMADS, p38 MAPK, NF-κB/IκBα, NF-κB-NLRP3, PI3K/Akt, TLR4-MyD88-NF-κB and IL-6/STAT3 signaling pathways are mainly involved. In conclusion, CM is very likely to be a potential candidate for liver disease treatment based on modern phytochemistry, pharmacology, and genomeproteomics, which needs more clinical trials to further clarify its importance in the treatment of liver diseases.

Hepatoprotective Plants from Bangladesh: A Biophytochemical Review and Future Prospect

Liver diseases are quite prevalant in many densely populated countries, including Bangladesh. The liver and its hepatocytes are targeted by virus and microbes, as well as by chemical environmental toxicants, causing wide-spread disruption of metabolic fuctions of the human body, leading to death from end-stage liver diseases. The aim of this review is to systematically explore and record the potential of Bangladeshi ethnopharmacological plants to treat liver diseases with focus on their sources, constituents, and therapeutic uses, including mechanisms of actions (MoA). A literature survey was carried out using Pubmed, Google Scholar, ScienceDirect, and Scopus databases with articles reported until July, 2020. A total of 88 Bangladeshi hepatoprotective plants (BHPs) belonging to 47 families were listed in this review, including Euphorbiaceae, Cucurbitaceae, and Compositae families contained 20% of plants, while herbs were the most cited (51%) and leaves were the most consumed parts (23%) as surveyed. The effect of BHPs against different hepatotoxins was observed via upregulation of antioxidant systems and inhibition of lipid peroxidation which subsequently reduced the elevated liver biomarkers. Different active constituents, including phenolics, curcuminoids, cucurbitanes, terpenoids, fatty acids, carotenoids, and polysaccharides, have been reported from these plants. The hepatoameliorative effect of these constituents was mainly involved in the reduction of hepatic oxidative stress and inflammation through activation of Nrf2/HO-1 and inhibition of NF-κB signaling pathways. In summary, BHPs represent a valuable resource for hepatoprotective lead therapeutics which may offer new alternatives to treat liver diseases.

Preclinical Evidence of Curcuma longa and Its Noncurcuminoid Constituents against Hepatobiliary Diseases: A Review

Hepatobiliary disease currently serves as an important public health issue due to the fact that it is one of the major causes of death among economically active individuals and can easily progress to chronic diseases. Despite the development of vaccines and numerous drugs, a definite treatment remains lacking owing to different stages of the disease itself, its intricate pathogenesis, an effect uncertainty for long-term use, resistance, and side effects. Curcuma longa (C. longa), which belongs to the family Zingiberaceae and the genus Curcuma, has long been used not only as spice for curry or dye but also as a constituent of herbal formula for the treatment of different diseases due to its bioactive activities. Recently, many studies on the experimental results of C. longa have been published relative to hepatobiliary diseases such as fatty liver, hepatitis, cirrhosis, and tumors. Therefore, in this review, we aimed to summarize the pharmacological effects and underlying molecular mechanisms of C. longa and its four compounds, β-elemene, germacrone, ar-turmerone, and bisacurone, against hepatobiliary diseases. C. longa exhibited antioxidant, hepatoprotective, antisteatotic, anti-inflammatory, antifibrotic, antitumor, and cholagogic effects by regulating apoptosis, CYP2E1, Nrf, lipid metabolism-related factors, TGF-β, NF-κB, CYP7A1, and so on. In particular, β-elemene could be an attractive compound owing to its remarkable hepatoprotective, anti-inflammatory, antifibrotic, and antitumor activities. Altogether, the present review provides a preclinical basis for the efficacy of C. longa as an effective therapeutic agent for the prevention and treatment of hepatobiliary diseases, despite the need for further studies to establish the extraction conditions and separation of active constituents with high bioavailability, and warrants further evaluation in clinical trials.

Kaempferol Protects Cell Damage in In Vitro Ischemia Reperfusion Model in Rat Neuronal PC12 Cells

Ischemic cerebral stroke is a severe neurodegenerative disease with high mortality. Ischemia and reperfusion injury plays a fundamental role in ischemic cerebral stroke. To date, the strategy for ischemic cerebral stroke treatment is limited. In the present study, we aimed to investigate the effect of kaempferol (KFL), a natural flavonol, on cell injury induced by oxygen and glucose deprivation (OGD) and reoxygenation (OGD-reoxygenation) in PC12 cells. We found that KFL inhibited OGD-induced decrease of cell viability and the increase of lactate dehydrogenase (LDH) release. OGD-induced activation of mitochondrial dysfunction, mitochondrial apoptotic pathway, and apoptosis was inhibited by KFL. KFL also reduced OGD-induced oxidative stress in PC12 cells. P66shc expression and acetylation were increased by OGD and KFL inhibited these changes. Upregulation of P66shc suppressed KFL-induced decrease of apoptosis, the decrease of LDH release, and the increase of cell viability. Furthermore, KFL inhibited OGD-induced decrease of sirtuin 1 (SIRT1) expression and downregulation of SIRT1 blocked KFL-induced decrease of apoptosis, the decrease of LDH release, and the increase of cell viability. In summary, we identified that KFL exhibited a beneficial effect against OGD-induced cytotoxicity in an ischemia/reperfusion injury cell model. The findings suggest that KFL may be a promising choice for the intervention of ischemic stroke and highlighted the SIRT1/P66shc signaling.

Ultrastructural Changes in Hepatocytes and Chemopreventive Effects of Short-Term Administration of Curcuma longa L. against Oxidative Stress-Induced Toxicity: Improvement Mechanisms of Liver Detoxification

The rhizomes of Curcuma longa L. (CL) have been widely used in herbal medicines worldwide. It has been shown to possess prophylactic effects against oxidative stress. However, there is a paucity of information regarding the protective role of CL against oxidative stress in the absence of toxic agents. The aim of the study was to elucidate the antioxidative stress pharmacodynamics of CL. Eighteen 12-week-old Sprague-Dawley rats weighing about 300 ± 25 gm were divided equally into six groups. Four of the groups were supplemented with CL at 100 mg/kg b.w./day orally (P.O.) and labeled as 1^st, 3^rd, 5^th, and 6^th day groups. The PCx (positive control) group was given distilled water orally, and the NCx (negative control) group rats were provided with food and water ad libitum. Blood samples were collected, and rats were sacrificed on days 1, 3, 5, and 6 (2 h) posttreatment. The blood was used for oxidative stress enzyme analysis (SOD, GSH-Px, and MDA) and liver (ALT) and kidney (creatinine) function assay, and the liver was dissected for histology. The results revealed that CL exhibited an antioxidative stress effect in the liver and kidneys as indicated by the low levels of ALT and creatinine. In response to antioxidant enzymes, especially that of the 3^rd-day treatment group, an increase in SOD and GSH-Px indirectly caused an alleviation of oxidative stress, leading to a much lower level of MDA. It was concluded that treatment with CL at 100 mg/kg b.w./per day for three consecutive days demonstrated the highest efficacy in abating oxidative stress in rats.

Therapeutic effects of AdipoRon on liver inflammation and fibrosis induced by CCl4 in mice

OBJECTIVE

The present work aimed to investigate the effects of AdipoRon against acute hepatitis and liver fibrosis induced by carbon tetrachloride (CCl₄) in mice.

METHODS

C57BL/6 mice were randomly divided into five groups: control, model, AdipoRon groups (three different dosages), CCl₄ was administered to induce acute hepatitis or liver fibrosis except for control group. The liver function, inflammatory and fibrotic profiles were evaluated by histology, immunohistochemistry and expression analysis, respectively.

RESULTS

AdipoRon pretreatment effectively attenuated oxidative stress and hepatocellular damage in acute CCl₄ intoxication, demonstrated by marked reduction in peroxidation indexes [hepatic malonaldehyde (MDA), total nitric oxide synthase (tNOS), inducible nitric oxide synthase (iNOS)] and serum transaminases [alanine aminotransferase (ALT), aspartate transaminase (AST)]. Moreover, AdipoRon attenuated the severity of fibrosis induced by sustaining CCl₄ challenge, with the alleviation of fibrous deposit and architecture distortion. The levels of canonical fibrosis markers (aminotransferases, hydroxyproline, hyaluronic acid, laminin) were also dose-dependently modulated by AdipoRon. Immunochemistry and expression analysis showed AdipoRon restrained the proinflammatory and profibrotic cytokines (TNF-α, TGF-β1, α-SMA, COL1A1), which somehow, ascribed the anti-fibrotic action to inhibiting hepatic stellate cells (HSCs) activation and quenching specific inflammation-fibrogenesis pathways.

CONCLUSIONS

AdipoRon demonstrates a remedial capacity against hepatitis and fibrosis induced by CCl₄, potentially by inflammation restraint and HSC deactivation, which might pave the way for its therapeutical application in hepatic fibrosis.

Effect of curcumin supplementation on TLR4 mediated non-specific immune responses in liver of laying hens under high-temperature conditions

The liver performs a significant role in innate and adaptive immunity. Heat stress causes oxidative stress in liver tissues and reduces the immune responses of laying hens which can cause several diseases affecting poultry-production performance. Hepatic inflammation is a common trigger of liver disease, which is reflected by hepatic tissue damage leading to fibrogenesis and hepatocellular carcinoma. Dietary manipulation of curcumin has been proposed to ameliorate the immune status of chickens under heat stress. Thus, this study aimed to investigate the effect of curcumin supplementation on TLR4 mediated non-specific immune response in liver of laying hens under high-temperature conditions. Experimental groups contained two controls groups (high temperature and thermo-neutral control (HC and NC) fed basal diet) and three high-temperature curcumin treatments groups (HT100, HT200 and HT300). Laying hens in HC and HT groups exposed 6 h/day heat stress (32 ± 1 °C). The results of present study showed that heat stress curcumin treatment group had reduced inflammatory responses (IL-6, IL-1β, TNF-α) as compared to HC and NC group. Pathological lesions and DNA damage of immune tissues were decreased in heat stress curcumin supplementation as compared to HC and NC group. Furthermore, PCNA, TLR4 and its downstream gene expression as well as protein expression (TLR4, NF-κB and PCNA) were significantly down regulated in heat stress curcumin supplemented group as compared to HC and NC group. Therefore, it is concluded that heat stressed hens supplemented with dietary curcumin enhance the immunity of laying hens and combat stressful environmental conditions.

Herbal Drugs: Friend or Foe?

We herein report a rather peculiar case of acute liver injury. A 78-year-old woman developed asthenia and weakness. Her previous medical history was irrelevant, except for having received etoricoxib 60 mg/24 h for osteoarthritis 1 month before. Liver biochemistry indicated hepatic failure; all tests for viral, bacterial, or parasitic infections were negative, as were the autoimmunity tests. As the patient's status gradually declined, a transjugular hepatic biopsy was obtained and confirmed hepatocyte necrosis with severe inflammation and presence of numerous eosinophils. Suspecting a potential toxic cause of the disorder, the patient was requestioned and admitted curcuma consumption for a long time. She was asked to discontinue it and her status gradually improved, with normalization of all the analytical parameters. On the long-term follow-up, she remains well. We consider that this case of acute liver injury can be explained with the combination of the acute toxic effect of a drug, etoricoxib, and the herbal remedy curcuma. This case is illustrative of the risk of interactions between drugs and natural remedies, and to the best of our knowledge, it is the first case of severe hepatotoxicity related to etoricoxib, probably potentiated by long-term curcumin intake. Besides, it illustrates the fact that patients do not generally consider natural remedies as potential source of toxicity, and this can lead to a delay in diagnosis.

Chinese Herbal Medicine for Wilson's Disease: A Systematic Review and Meta-Analysis

Wilson's disease (WD) is a rare autosomal recessive inherited disorder of chronic copper toxicosis. Currently, Chinese herbal medicines (CHM) is widely used for WD. Here, we conducted an updated systematic review to investigate the efficacy and safety of CHM for WD and its possible mechanisms. Randomized-controlled clinical trials (RCTs), which compared CHM with Western conventional medicine or placebo for WD, were searched in six databases from inception to July 2017. The methodological quality was assessed using 7-item criteria from the Cochrane's collaboration tool. All the data were analyzed using Rev-Man 5.3 software. Eighteen studies involving 1,220 patients were identified for the final analyses. A score of study quality ranged from 2/7 to 4/7 points. Meta-analyses showed that CHM could significantly increase 24-h urinary copper excretion and improve liver function and the total clinical efficacy rate for WD compared with control (p < 0.05). Additionally, CHM was well tolerated in patients with WD. The underlying mechanisms of CHM for WD are associated with reversing the ATP7B mutants, exerting anti-oxidation, anti-inflammation, and anti-hepatic fibrosis effects. In conclusion, despite the apparent positive results, the present evidence supports, to a limited extent because of the methodological flaws and CHM heterogeneity, that CHM paratherapy can be used for patients with WD but could not be recommended as monotherapy in WD. Further rigorous RCTs focusing on individual CHM formula for WD are warranted.

Mechanistic insights of hepatoprotective effects of curcumin: Therapeutic updates and future prospects

The liver is the most essential organ of the body performing vital functions. Hepatic disorders affect the physiological and biochemical functions of the body. These disorders include hepatitis B, hepatitis C, alcoholic liver disease (ALD), nonalcoholic fatty liver disease (NAFLD), liver cirrhosis, hepatic failure and hepatocellular carcinoma (HCC). Drugs related hepatotoxicity is one of the major challenges facing by clinicians as it is a leading cause of liver failure. During post-marketing surveillance studies, detection and reporting of drug-induced hepatotoxicity may lead to drug withdrawal or warnings. Several mechanisms are involved in hepatotoxicity such as cell membrane disruption, initiating an immune response, alteration of cellular pathways of drug metabolism, accumulation of reactive oxygen species (ROS), lipid peroxidation and cell death. Curcumin, the active ingredient of turmeric and exhibits therapeutic potential for the treatment of diabetes, cardiovascular disorders and various types of cancers. Curcumin is strong anti-oxidant and anti-inflammatory effects and thus it possesses hepatoprotective properties. Despite its low bioavailability, its hepatoprotective effects have been studied in various protocols of hepatotoxicity including acetaminophen, alcohol, lindane, carbon tetrachloride (CCL4), diethylnitrosamine and heavy metals induced hepatotoxicities. This report reviews the hepatoprotective effects of curcumin with a focus on its mechanistic insights in various hepatotoxic protocols.

Synthesis, characterization, and pharmacological evaluation of zinc oxide nanoparticles formulation

Zinc oxide nanoparticles (ZnONPs) are being used extensively in manufacturing skin lotions and food products and in various biological and pharmaceutical industries because of their immunomodulatory and antimicrobial properties. In this study, ZnONPs were synthesized by a precipitation method and characterized by X-ray diffraction (XRD) techniques, scanning electron microscopy (SEM), and ultraviolet-visible spectroscopy to investigate their structural, morphological, and optical properties. For in vivo evaluation, 40 healthy albino mice were randomly allocated to four equal groups among which the first one was the control group, while the second, third, and fourth were treated with carbon tetrachloride (CCl₄), a blend of CCl₄ and ZnONPs, and ZnONPs alone, respectively, for 21 days. The XRD analysis confirmed hexagonal wurtzite type structures having an average crystallite size of 41.54 nm. The morphology of ZnONPs analyzed through SEM showed uniform distribution of the grains and shape of the synthesized oxide. The energy band gap of the ZnONPs was found to be 3.498 eV. Hepatic and renal damage following CCl₄ administration was apparent after 14 days and was increased at the 21st day, showing nodular fibrotic masses in the liver and bumpy surfaces in the kidney as observed by gross and histological examination. Coadministration of ZnONPs (15 mg/kg b.w. intragastrically 5 days a week) significantly prevented the CCl₄-dependent increases in alanine transaminase, aspartate transaminase, creatinine, and urea levels, suggesting a protective potential of ZnONPs.

Dual protective effect of ginger and rosemary extracts against CCl4-induced hepatotoxicity in rats

The present study aimed to investigate the protective effect of aqueous extracts of ginger (GE) and rosemary (RE), both individually and in combination, on carbon tetrachloride (CCl4)-induced liver injury in adult male rats. CCl4 induced significant increase in liver enzymes, bilirubin, triglycerides, and total cholesterol while total protein, albumin, and globulin were significantly decreased. Also, the activity of cytochrome P450 (CYP) and oxidative stress markers were found to be elevated with a concomitant decrease in the activity of antioxidant enzymes in hepatic tissue. Supplementation with extracts of ginger or rosemary effectively relieved most of the CCl4-induced alterations when administered singly. The joint therapy of the two extracts was more effective. The histological investigation strongly confirmed the highly protective effect of the two plant extracts in the hepatocytes. These findings suggest that rosemary and ginger extracts are effective in improving both the function and structure of the hepatocytes through their potent antioxidant effect and point out to the possibility of using a combination of both as an adjunct therapy in liver diseases.

Oral Delivery of Curcumin Polymeric Nanoparticles Ameliorates CCl₄-Induced Subacute Hepatotoxicity in Wistar Rats

Curcumin is the major bioactive compound of Curcuma longa, an important medicinal plant used in traditional herbal formulations since ancient times. In the present study, we report that curcumin nanoparticles (ηCur) protects Wistar rats against carbon tetrachloride (CCl₄)-induced subacute hepatotoxicity. Nanoparticles of sizes less than 220 nm with spherical shape were prepared using PLGA and PVA respectively as polymer and stabilizer. Test animals were injected via intraperitoneal route with 1 mL/kg CCl₄ (8% in olive oil) twice a week over a period of 8 weeks to induce hepatotoxicity. On the days following the CCl₄ injection, test animals were orally administered with either curcumin or its equivalent dose of ηCur. Behavioural observation, biochemical analysis of serum and histopathological examination of liver of the experimental animals indicated that ηCur offer significantly higher hepatoprotection compared to curcumin.

An in vitro comparative study of the antioxidant activity and SIRT1 modulation of natural compounds

Oxidative stress arises from an imbalance between the production of free radicals and antioxidant defences. Several studies have suggested that dietary antioxidants (such as polyphenols and berberine) may counteract oxidative stress through the involvement of the Sirtuin 1/Adenosine Monophosphate-Activated Protein Kinase (SIRT1/AMPK) pathway. The aim of this study was to evaluate the direct and specific antioxidant activity of some natural compounds, as well as their ability to modulate the expression of SIRT1 and the activation of AMPK. Quercetin, tyrosol, ferulic acid, catechin, berberine and curcumin were evaluated for their specific and direct antioxidant activity with TOSC assay. Their ability to modulate SIRT1 and AMPK was assessed by immunoblotting assay, while their cytotoxicity by CellTiter-Blue Cell Viability Assay. No statistically significant decrease (p > 0.05) in the number of viable cells was found upon challenging with the natural compounds. Quercetin exhibited the highest antioxidant activity against peroxyl radical and peroxinitrate derivates, while curcumin showed the best anti-hydroxyl activity with respect to the other compounds and, most importantly, respect to the reference antioxidants. Finally, all the tested compounds significantly increased the SIRT1 expression and the activation of AMPK. Our results clearly disclose the specific antioxidant activity of these natural compounds and their ability to increase SIRT1 expression and AMPK activation.

Curcumin Attenuates on Carbon Tetrachloride-Induced Acute Liver Injury in Mice via Modulation of the Nrf2/HO-1 and TGF-β1/Smad3 Pathway

This study aimed to investigate the protective effect of curcumin against carbon tetrachloride (CCl₄)-induced acute liver injury in a mouse model, and to explain the underlying mechanism. Curcumin at doses of 50, 100 and 200 mg/kg/day were administered orally once daily for seven days prior to CCl₄ exposure. At 24 h, curcumin-attenuated CCl₄ induced elevated serum transaminase activities and histopathological damage in the mouse's liver. Curcumin pre-treatment at 50, 100 and 200 mg/kg significantly ameliorated CCl₄-induced oxidative stress, characterized by decreased malondialdehyde (MDA) formations, and increased superoxide dismutase (SOD), catalase (CAT) activities and glutathione (GSH) content, followed by a decrease in caspase-9 and -3 activities. Curcumin pre-treatment significantly decreased CCl₄-induced inflammation. Furthermore, curcumin pre-treatment significantly down-regulated the expression of TGF-β1 and Smad3 mRNAs (both p < 0.01), and up-regulated the expression of nuclear-factor erythroid 2-related factor 2 (Nrf2) and HO-1 mRNA (both p < 0.01) in the liver. Inhibition of HO-1 attenuated the protective effect of curcumin on CCl₄-induced acute liver injury. Given these outcomes, curcumin could protect against CCl₄-induced acute liver injury by inhibiting oxidative stress and inflammation, which may partly involve the activation of Nrf2/HO-1 and inhibition of TGF-β1/Smad3 pathways.