Curcumin attenuated paracetamol overdose induced hepatitis

Post-COVID-19 approach to teaching an undergraduate laboratory class focused on experimental design and data interpretation

To best prepare students for the real-world research environment, key skills, including experimental design, data analysis, communication of results, and critical thinking, should be key components of undergraduate science courses. Furthermore, the impact of the COVID-19 pandemic on in-person teaching has resulted in a need to develop courses that enable flexible learning. This paper details the laboratory component of a senior-level toxicology class that was developed to emphasize all these skills and allow for flexible learning. The aim of the laboratory class was for students to determine how curcumin protected against acetaminophen-induced hepatoxicity. To stimulate critical thinking, students were required to choose a maximum of four experiments from the six on offer. Before conducting an experiment, students stated a hypothesis and selected the appropriate treatment groups. Once an experiment was completed, students were given access to a complete dataset, on which they performed statistical analysis and drew conclusions. Students who were unable to attend the laboratory session in person were able to complete the required pre-lab work and access the dataset. Following each experiment, students could write a lab summary, and receive thorough feedback. The final assessment was a written manuscript of their findings as well as a chance to respond to reviewer comments. This teaching approach prioritized the critical thinking, analysis, and experimental design aspects of scientific research. Overall, this structure was well received by students and it could easily be adapted for use on other life science courses.

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.

Involvement of Nrf2, JAK and COX pathways in acetaminophen-induced nephropathy: Role of some antioxidants

Objectives

Acetaminophen (APAP)-induced nephrotoxicity is detrimental consequence for which there has not been a standardized therapeutic regimen. Although, N-acetylcysteine (NAC) is a well-known antidote used in APAP-induced hepatotoxicity, its benefit in nephrotoxicity caused by APAP is almost lacking. This study aimed to compare the possible protective effect of thymoquinone (TQ), curcumin (CR), and α-lipoic acid (α-LA), either in solo or in combination regimens with that of NAC against APAP-induced renal injury.

Design and method

Rats were divided into nine groups; control group, APAP intoxicated group (1000 mg/kg; orally), and the remaining seven groups received, in addition to APAP, oral doses of NAC, TQ, CR, α-LA, CR plus TQ, TQ plus α-LA, or CR plus α-LA. The first dose of the aforementioned antioxidants was given 24 h before APAP, and then the second dose was given 2 h after APAP, whereas the last dose was given 10 h after administration of APAP.

Results

Treatment with APAP elevated kidney markers like serum uric acid, urea, and creatinine. In addition, it increased the serum level of tumor necrosis factor alpha (TNF-α), interleukin-1beta (IL-1β) and thiobarbituric acid reactive species (TBARS). Also, the protein expression of renal janus kinase (JAK) and cyclooxygenase (COX)-2 were all upregulated by APAP. In contrast, the expression of Nrf2 and the renal levels of superoxide dismutase and glutathione were downregulated. Treatment with the indicated natural antioxidants resulted in amelioration of the aberrated parameters through exhibiting anti-inflammatory, antioxidant and free radical-scavenging effects with a variable degree.

Conclusion

The combined administration of CR and TQ exerted the most potent protection against APAP-induced nephrotoxicity through its anti-inflammatory and free radical-scavenging effects (antioxidant) which were comparable to that of NAC-treatment.

Calcitriol Protects against Acetaminophen-Induced Hepatotoxicity in Mice

Acetaminophen (APAP) overdose is one of the major causes of acute liver failure. Severe liver inflammation and the production of oxidative stress occur due to toxic APAP metabolites and glutathione depletion. Growing evidence has proved that vitamin D (VD) exerts anti-inflammatory and antioxidative functions. Our objective was to explore the protective role of calcitriol (VD3) in acute APAP-induced liver injury. Methods: Adult male mice were randomized into three groups; control (n = 8), APAP (n = 8), and VD3 group (n = 8). All mice, except controls, received oral administration of APAP (400 mg/kg) and were sacrificed 24 h later. In the VD3 group, calcitriol (10 µg/kg) was injected intraperitoneally 24 h before and after exposure to APAP. Blood samples were collected to assess serum aminotransferase and inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6)]. Liver tissues were analyzed for hepatic glutathione (GSH), malondialdehyde (MDA), and histopathology. Results: APAP administration significantly increased serum aminotransferase, inflammatory cytokines, and induced cellular inflammation and necrosis. APAP also depleted hepatic GSH and elevated oxidative stress, as indicated by high MDA levels. In the APAP group, 25% of the mice (two out of eight) died, while no deaths occurred in the VD3 group. Treatment with calcitriol significantly reduced serum aminotransferase, TNF-α, and IL-6 levels in the VD3 group compared to the APAP group. Additionally, VD3 effectively restored GSH reserves, reduced lipid peroxidation, and attenuated hepatotoxicity. Conclusions: These findings demonstrate that VD3 prevents APAP-induced acute liver injury and reduces mortality in mice through its anti-inflammatory and antioxidative activity. Thus, VD3 might be a novel treatment strategy for APAP-induced hepatotoxicity.

Sensitization of GSH synthesis by curcumin curtails acrolein-induced alveolar epithelial apoptosis via Keap1 cysteine conjugation: A randomized controlled trial and experimental animal model of pneumonitis

INTRODUCTION

Epidemiological studies have reported an association between exposures to ambient air pollution and respiratory diseases, including chronic obstructive pulmonary disease (COPD). Pneumonitis is a critical driving factor of COPD and exposure to air pollutants (e.g., acrolein) is associated with increased incidence of pneumonitis.

OBJECTIVES

Currently available anti-inflammatory therapies provide little benefit against respiratory diseases. To this end, we investigated the preventive role of curcumin against air pollutant-associated pneumonitis and its underlying mechanism.

METHODS

A total of 40 subjects was recruited from Chengdu, China which is among the top three cities in terms of respiratory mortality related to air pollution. The participants were randomly provided either placebo or curcumin supplements for 2 weeks and blood samples were collected at the baseline and at the end of the intervention to monitor systemic markers. In our follow up mechanistic study, C57BL/6 mice (n = 40) were randomly allocated into 4 groups: Control group (saline + no acrolein), Curcumin only group (curcumin + no acrolein), Acrolein only group (saline + acrolein), and Acrolein + Curcumin group (curcumin + acrolein). Curcumin was orally administered at 100 mg/kg body weight once a day for 10 days, and then the mice were subjected to nasal instillation of acrolein (5 mg/kg body weight). Twelve hours after single acrolein exposure, all mice were euthanized.

RESULTS

Curcumin supplementation, with no noticeable adverse responses, reduced circulating pro-inflammatory cytokines in association with clinical pneumonitis as positive predictive while improving those of anti-inflammatory cytokines. In the pre-clinical study, curcumin reduced pneumonitis manifestations by suppression of intrinsic and extrinsic apoptotic signaling, which is attributed to enhanced redox sensing of Nrf2 and thus sensitized synthesis and restoration of GSH, at least in part, through curcumin-Keap1 conjugation.

CONCLUSIONS

Our study collectively suggests that curcumin could provide an effective preventive measure against air pollutant-enhanced pneumonitis and thus COPD.

Acetaminophen-induced liver injury: Molecular mechanism and treatments from natural products

Acetaminophen (APAP) is a widely used analgesic and antipyretic over-the-counter medicine worldwide. Hepatotoxicity caused by APAP overdose is one of the leading causes of acute liver failure (ALF) in the US and in some parts of Europe, limiting its clinical application. Excessive APAP metabolism depletes glutathione and increases N-acetyl-p-benzoquinoneimide (NAPQI) levels, leading to oxidative stress, DNA damage, and cell necrosis in the liver, which in turn leads to liver damage. Studies have shown that natural products such as polyphenols, terpenes, anthraquinones, and sulforaphane can activate the hepatocyte antioxidant defense system with Nrf2 as the core player, reduce oxidative stress damage, and protect the liver. As the key enzyme metabolizing APAP into NAPQI, cytochrome P450 enzymes are also considered to be intriguing target for the treatment of APAP-induced liver injury. Here, we systematically review the hepatoprotective activity and molecular mechanisms of the natural products that are found to counteract the hepatotoxicity caused by APAP, providing reference information for future preclinical and clinical trials of such natural products.

Critical Review on Nutritional, Bioactive, and Medicinal Potential of Spices and Herbs and Their Application in Food Fortification and Nanotechnology

Medicinal or herbal spices are grown in tropical moist evergreen forestland, surrounding most of the tropical and subtropical regions of Eastern Himalayas in India (Sikkim, Darjeeling regions), Bhutan, Nepal, Pakistan, Iran, Afghanistan, a few Central Asian countries, Middle East, USA, Europe, South East Asia, Japan, Malaysia, and Indonesia. According to the cultivation region surrounded, economic value, and vogue, these spices can be classified into major, minor, and colored tropical spices. In total, 24 tropical spices and herbs (cardamom, black jeera, fennel, poppy, coriander, fenugreek, bay leaves, clove, chili, cassia bark, black pepper, nutmeg, black mustard, turmeric, saffron, star anise, onion, dill, asafoetida, celery, allspice, kokum, greater galangal, and sweet flag) are described in this review. These spices show many pharmacological activities like anti-inflammatory, antimicrobial, anti-diabetic, anti-obesity, cardiovascular, gastrointestinal, central nervous system, and antioxidant activities. Numerous bioactive compounds are present in these selected spices, such as 1,8-cineole, monoterpene hydrocarbons, γ-terpinene, cuminaldehyde, trans-anethole, fenchone, estragole, benzylisoquinoline alkaloids, eugenol, cinnamaldehyde, piperine, linalool, malabaricone C, safrole, myristicin, elemicin, sinigrin, curcumin, bidemethoxycurcumin, dimethoxycurcumin, crocin, picrocrocin, quercetin, quercetin 4'-O-β-glucoside, apiol, carvone, limonene, α-phellandrene, galactomannan, rosmarinic acid, limonene, capsaicinoids, eugenol, garcinol, and α-asarone. Other than that, various spices are used to synthesize different types of metal-based and polymer-based nanoparticles like zinc oxide, gold, silver, selenium, silica, and chitosan nanoparticles which provide beneficial health effects such as antioxidant, anti-carcinogenic, anti-diabetic, enzyme retardation effect, and antimicrobial activity. The nanoparticles can also be used in environmental pollution management like dye decolorization and in chemical industries to enhance the rate of reaction by the use of catalytic activity of the nanoparticles. The nutritional value, phytochemical properties, health advantages, and both traditional and modern applications of these spices, along with their functions in food fortification, have been thoroughly discussed in this review.

The Effect of Curcumin Nanoparticles on Paracetamol-induced Liver Injury in Male Wistar Rats

INTRODUCTION

Curcumin is a naturally occurring compound that has antioxidant properties, acts as a hepatoprotective, and lowers lipid peroxidation. However, curcumin's low solubility and bioavailability are its primary drawbacks and prevent its use as a therapeutic agent. In this study, curcumin nanoparticles will be created using the ultrasonic-assisted extraction method, and their effectiveness against paracetamol-induced changes in ALT, AST, SOD, MDA, and TNF-α will be compared to that of pure curcumin.

PURPOSE

This study aimed to determine the hepatoprotective effect of curcumin nanoparticles in paracetamol- induced rats as a model for liver injury.

METHODS

Thirty-six male Wistar rats, aged 6 to 8 weeks, with a minimum weight of 120 grams, were used in an experimental laboratory investigation with a post-test-only group design. Rats in each group received 100 mg/kgBW pure curcumin, 100 mg/kgBW curcumin nanoparticles, and 50 mg/kgBW curcumin nanoparticles for 7 days before paracetamol induction. On day 8, 300 mg/kgBW of paracetamol was intraperitoneally injected to cause liver damage. One of the groups received NAC as an antidote 10 hours after paracetamol induction. Detection of ALT and AST using a Chemistry Analyzer. ELISA approach for the detection of SOD, MDA, and TNF-α. The Roenigk score was calculated by two examiners after the liver histopathology preparations were stained using the Hematoxylin-Eosin method. Post hoc analyses were performed after the One Way Annova and Kruskal Wallis tests to examine the data.

RESULTS

According to PSA results, the smallest formula that formed curcumin nanoparticles (10.2 nm) was 8 g of curcumin formula mixed with a mixture of Tween 20 4.5 ml, Kolliphor EL 1.5 ml, Propylene Glycol 1.5 ml, and Capryol 90 1 ml for 21 minutes using an ultrasonic process. MDA and TNF-α levels, as well as the liver's histological Roenigk score, were significantly lower in the 100 mg/kgBB pure curcumin group (C100) when compared to the model group (model). The levels of AST, MDA, TNF-α, and the liver histopathology score were significantly lower in the 100 mg/kgBB (NC100) and 50 mg/kgBB (NC50) curcumin nanoparticle groups compared to the model group (model) and pure curcumin group (C100) (p< 0.05).

CONCLUSION

Curcumin nanoparticles showed better hepatoprotective ability than pure curcumin.

Hepato-Protection Effect of Curcumin Against Methylphenidate-Induced Hepatotoxicity: Histological and Biochemical Evidences

Background

As a psychostimulant agent, methylphenidate (MPH) abuse can cause serious liver damage. Studies have documented the hepatoprotective impacts of curcumin on liver damage. According to this definition, the purpose of this study is to explain the hapatoprotective effects of curcumin against the hepatotoxicity induced by MPH.

Methods

Seventy rats were equally divided into seven groups (10 rats per group). Groups 1 and 2 received normal saline (0.7 mL/rat) and MPH (10 mg/kg), respectively for 21 days. Groups 3, 4, 5, and 6 concurrently received MPH (10 mg/ kg) and curcumin (10, 20, 40, and 60 mg/kg, respectively) for 21 days. Group 7 was treated with curcumin (60 mg/kg) alone for 21 days. The hepatic function test key enzymes such as AST, ALP, and histology of liver tissue (ALT), and alkaline phosphatase (ALP) levels was studied in the blood samples, and also, the histopathological changes and cell density changes were evaluated in the liver tissue.

Results

The latest studies have shown that the administration of MPH induces rises in the AST, ALT, and ALP levels and induces degeneration changes in histopathology, whereas curcumin administration at doses of 40 and 60 mg/kg reduced the elevation of MPH-induced hepatic enzyme and inhibited histopathological degeneration in the MPH-treated classes. Curcumin alone (60 mg/kg) did not alter the biochemical and histological parameters.

Conclusions

Curcumin can function as a hepatoprotective agent against MPH-induced hepatotoxicity.

A Comprehensive Review on the Therapeutic Potential of Curcuma longa Linn. in Relation to its Major Active Constituent Curcumin

Curcuma longa Linn. (C. longa), popularly known as turmeric, belongs to the Zingiberaceae family and has a long historical background of having healing properties against many diseases. In Unani and Ayurveda medicine, C. longa has been used for liver obstruction and jaundice, and has been applied externally for ulcers and inflammation. Additionally, it is employed in several other ailments such as cough, cold, dental issues, indigestion, skin infections, blood purification, asthma, piles, bronchitis, tumor, wounds, and hepatic disorders, and is used as an antiseptic. Curcumin, a major constituent of C. longa, is well known for its therapeutic potential in numerous disorders. However, there is a lack of literature on the therapeutic potential of C. longa in contrast to curcumin. Hence, the present review aimed to provide in-depth information by highlighting knowledge gaps in traditional and scientific evidence about C. longa in relation to curcumin. The relationship to one another in terms of biological action includes their antioxidant, anti-inflammatory, neuroprotective, anticancer, hepatoprotective, cardioprotective, immunomodulatory, antifertility, antimicrobial, antiallergic, antidermatophytic, and antidepressant properties. Furthermore, in-depth discussion of C. longa on its taxonomic categorization, traditional uses, botanical description, phytochemical ingredients, pharmacology, toxicity, and safety aspects in relation to its major compound curcumin is needed to explore the trends and perspectives for future research. Considering all of the promising evidence to date, there is still a lack of supportive evidence especially from clinical trials on the adjunct use of C. longa and curcumin. This prompts further preclinical and clinical investigations on curcumin.

Protective effects of curcumin and silymarin against paracetamol induced hepatotoxicity in adult male albino rats

BACKGROUND

Acute paracetamol (PCM) toxicity is a clinical problem; can result in a serious liver injury that finally may progress to acute liver failure. Curcumin (CUR) is a prevalent natural compound that can maintain prooxidant/antioxidant balance and thus can help in liver protection; also, Silymarin (SL) is a traditional antioxidant herb, used to treat liver disorders through scavenging free radicals. This study aimed to illustrate the histological, biochemical and molecular changes induced by acute PCM overdose on rats' liver to elucidate the effectiveness of CUR compared to SL in alleviating such changes.

MATERIALS AND METHODS

Male Wister Albino rats were divided into 6 groups each comprising 23 rats: control group, curcumin (CUR) treated group received (100 mg CUR/ kg), silymarin treated group received (100 mg SL/kg) for 7 successive days. Paracetamol (PCM) exposed group administered a single dose of PCM (200 mg/kg orally on 8th day). PCM + CUR group and PCM + SL group pretreated with CUR and SL respectively for 7 days then received single PCM dose (200 mg/kg) on the 8th day. Blood and liver tissues were collected for biochemical, histopathological and immunohistochemical analyses using anti-p53 antibody. In addition, real time polymerase chain reaction (RT- PCR) was used to measure Bax, bcl2 and Peroxisome proliferator-activated receptor-gamma (PPAR γ) mRNA expression levels.

RESULTS

In the paracetamol overdose group, the liver architecture showed necrotic changes, hydropic degeneration, congestion and dilatation of central veins. This hepatocellular damage was confirmed by a significant increase of AST, ALT levels and by an apparent increase in the number of p53 stained cells. PCM toxicity showed significant elevation of total oxidant status (TOS), oxidant status index (OSI) and decreased total antioxidant capacity (TAC) compared to controls (p < 0.001). Gene expression analysis showed that PCM caused an elevation of bcl2 and a reduction of both Bax and PPARγ mRNA expression. The histological alternation in the liver architecture was markedly improved in (PCM + CUR) group compared to (PCM+ SL) group, with an obvious decrease in the number of P53 stained cells. CUR pretreatment inhibited the elevation of TOS and OSI as well as the reduction of TAC caused by PCM toxicity compared to (PCM + SL) group.

CONCLUSION

Both SL and CUR pretreatment prevented the toxic effects of PCM, but CUR is more effective than SL in ameliorating acute PCM induced hepatotoxicity.

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.

Therapeutic Potential of Plants and Plant Derived Phytochemicals against Acetaminophen-Induced Liver Injury

Acetaminophen (APAP), which is also known as paracetamol or N-acetyl-p-aminophenol is a safe and potent drug for fever, pain and inflammation when used at its normal therapeutic doses. It is available as over-the-counter drug and used by all the age groups. The overdose results in acute liver failure that often requires liver transplantation. Current clinical therapy for APAP-induced liver toxicity is the administration of N-acetyl-cysteine (NAC), a sulphydryl compound an approved drug which acts by replenishing cellular glutathione (GSH) stores in the liver. Over the past five decades, several studies indicate that the safety and efficacy of herbal extracts or plant derived compounds that are used either as monotherapy or as an adjunct therapy along with conventional medicines for hepatotoxicity have shown favorable responses. Phytochemicals mitigate necrotic cell death and protect against APAP-induced liver toxicityby restoring cellular antioxidant defense system, limiting oxidative stress and subsequently protecting mitochondrial dysfunction and inflammation. Recent experimental evidences indicat that these phytochemicals also regulate differential gene expression to modulate various cellular pathways that are implicated in cellular protection. Therefore, in this review, we highlight the role of the phytochemicals, which are shown to be efficacious in clinically relevant APAP-induced hepatotoxicity experimental models. In this review, we have made comprehensive attempt to delineate the molecular mechanism and the cellular targets that are modulated by the phytochemicals to mediate the cytoprotective effect against APAP-induced hepatotoxicity. In this review, we have also defined the challenges and scope of phytochemicals to be developed as drugs to target APAP-induced hepatotoxicity.

Paracetamol: overdose-induced oxidative stress toxicity, metabolism, and protective effects of various compounds in vivo and in vitro

Paracetamol (APAP) is one of the most widely used and popular over-the-counter analgesic and antipyretic drugs in the world when used at therapeutic doses. APAP overdose can cause severe liver injury, liver necrosis and kidney damage in human beings and animals. Many studies indicate that oxidative stress is involved in the various toxicities associated with APAP, and various antioxidants were evaluated to investigate their protective roles against APAP-induced liver and kidney toxicities. To date, almost no review has addressed the APAP toxicity in relation to oxidative stress. This review updates the research conducted over the past decades into the production of reactive oxygen species (ROS), reactive nitrogen species (RNS), and oxidative stress as a result of APAP treatments, and ultimately their correlation with the toxicity and metabolism of APAP. The metabolism of APAP involves various CYP450 enzymes, through which oxidative stress might occur, and such metabolic factors are reviewed within. The therapeutics of a variety of compounds against APAP-induced organ damage based on their anti-oxidative effects is also discussed, in order to further understand the role of oxidative stress in APAP-induced toxicity. This review will throw new light on the critical roles of oxidative stress in APAP-induced toxicity, as well as on the contradictions and blind spots that still exist in the understanding of APAP toxicity, the cellular effects in terms of organ injury and cell signaling pathways, and finally strategies to help remedy such against oxidative damage.

Role of food-derived antioxidant agents against acetaminophen-induced hepatotoxicity

Context Acetaminophen (APAP), also known as paracetamol and N-acetyl p-aminophenol, is one of the most frequently used drugs for analgesic and antipyretic purposes on a worldwide basis. It is safe and effective at recommended doses but has the potential for causing hepatotoxicity and acute liver failure (ALF) with overdose. To solve this problem, different strategies have been developed, including the use of compounds isolated from food, which have been studied to characterize their efficacy as natural dietary antioxidants. Objective The objective of this study is to show the beneficial effects of a variety of natural compounds and their use against acetaminophen-induced hepatotoxicity. Methods PubMed database was reviewed to compile data about natural compounds with hepatoprotective effects against APAP toxicity. Results and conclusion As a result, the health-promoting properties of 13 different food-derived compounds with protective effect against APAP-induced hepatotoxicity were described as well as the mechanisms involved in hepatoprotection.

[Activity of liver mitochondrial NAD+-dependent dehydrogenases of the krebs cycle in rats with acetaminophen-induced hepatitis developed under conditions of alimentary protein deficiency]

Activity of isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, malate dehydrogenase, and the NAD(+)/NADН ratio were studied in the liver mitochondrial fraction of rats with toxic hepatitis induced by acetaminophen under conditions of alimentary protein deprivation. Acetaminophen-induced hepatitis was characterized by a decrease of isocitrate dehydrogenase, α-ketoglutarate dehydrogenase and malate dehydrogenase activities, while the mitochondrial NAD(+)/NADН ratio remained at the control level. Modeling of acetaminophen-induced hepatitis in rats with alimentary protein caused a more pronounced decrease in the activity of NAD(+)-dependent dehydrogenases studied and a 2.2-fold increase of the mitochondrial NAD(+)/NADН ratio. This suggests that alimentary protein deprivation potentiated drug-induced liver damage.

Hepatoprotective Effect of A Polyherbal Extract Containing Andrographis Paniculata, Tinospora Cordifolia and Solanum Nigrum Against Paracetamol Induced Hepatotoxicity

Background:

Traditionally, a number of medicinal plants are used to treat various types of hepatic disorders but few of them were pharmacologically evaluated for their safety and efficacy. The combination of Andrographis paniculata (Kalmegha), Tinospora cordifolia (Guduchi), and Solanum nigrum (Kakmachi) was traditionally used in Indian System of Medicine (Ayurveda) for the treatment of various liver-related disorders.

Objective:

In the present study, an attempt was made to substantiate the ethnopharmacological use of a traditional formulation in hepatoprotection against paracetamol-induced hepatotoxicity.

Subjects and Methods:

Swiss albino mice (weight 20–25 g) were used for this study. Intraperitoneal injection of paracetamol (500 mg/kg body weight) was used to induce hepatotoxicity. Serum levels of alanine transaminase, aspartate aminotransferase, bilirubin, alkaline phosphatase, were used as indices of liver injury. In addition total cholesterol, triglyceride, low-density lipoprotein, high-density lipoprotein and creatinine were also assayed using the standard procedure.

Results:

Among the two different doses, pretreatment with Polyherbal extract at 500 mg/kg body weight exhibited a significant (P < 0.05) hepatoprotective activity as compared to paracetamol group.

Conclusion:

The polyherbal extract exhibits a significant hepatoprotective effect in vivo. The study contributes to its use in traditional Ayurveda system for the management of liver diseases.

SUMMARY

Traditionally, a number of medicinal plants are used to treat various types of liver disorders but few of them were pharmacologically evaluated for their safety and efficacy. Combination of Andrographis paniculata (Kalmegha), Tinospora cordifolia (Guduchi), and Solanum nigrum (Kakmachi) was traditionally used in Ayurveda for the treatment of various liver related disorders. In the present study an attempt was made to validate the ethnopharmacological use of a traditional formulation in hepatoprotection against paracetamol induced hepatotoxicity. Swiss albino mice (weight 20-25 g) were used for this study. Intraperitoneal injection (IP) of paracetamol (500 mg/kg body weight) was used to induce hepatotoxicity. Serum levels of Alanine transaminase (ALT), Aspartate Aminotransferase (AST), Bilirubin, Alkaline phosphatase (ALP),. were used as indices of liver injury. In addition total cholesterol, triglyceride, Low density lipoprotein (LDL), High density lipoprotein (HDL) and creatinine were also assayed using standard procedure. Among the two different doses, pre-treatment with Polyherbal extract at 500 mg/kg body weight exhibited a significant (P < 0.05) hepatoprotective activity as compared to paracetamol group. The polyherbal extract exhibits significant hepatoprotective effect in vivo. The study contributes to its use in traditional Ayurveda system for the management of liver diseases.

Curcumin prevents paracetamol-induced liver mitochondrial alterations

OBJECTIVE

In the present study was evaluated if curcumin is able to attenuate paracetamol (PCM)-induced mitochondrial alterations in liver of mice.

METHODS

Mice (n = 5-6/group) received curcumin (35, 50 or 100 mg/kg bw) 90 min before PCM injection (350 mg/kg bw). Plasma activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) was measured; histological analyses were done; and measurement of mitochondrial oxygen consumption, mitochondrial membrane potential, ATP synthesis, aconitase activity and activity of respiratory complexes was carried out.

KEY FINDINGS

Curcumin prevented in a dose-dependent manner PCM-induced liver damage. Curcumin (100 mg/kg) attenuated PCM-induced liver histological damage (damaged hepatocytes from 28.3 ± 7.7 to 8.3 ± 0.7%) and increment in plasma ALT (from 2300 ± 150 to 690 ± 28 U/l) and AST (from 1603 ± 43 to 379 ± 22 U/l) activity. Moreover, curcumin attenuated the decrease in oxygen consumption using either succinate or malate/glutamate as substrates (evaluated by state 3, respiratory control ratio, uncoupled respiration and adenosine diphosphate/oxygen ratio), in membrane potential, in ATP synthesis, in aconitase activity and in the activity of respiratory complexes I, III and IV.

CONCLUSIONS

These results indicate that the protective effect of curcumin in PCM-induced hepatotoxicity is associated with attenuation of mitochondrial dysfunction.

Hepatoprotective and Anti-oxidant Activities ofGlossogyne tenuifoliaAgainst Acetaminophen-Induced Hepatotoxicity in Mice

The present study investigated the anti-oxidative and hepatoprotective effects of Glossogyne tenuifolia (GT) Cassini, against acetaminophen-induced acute liver injury in BALB/c mice. The extracts of GT by various solvents (hot water, 50% ethanol and 95% ethanol) were compared for their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, reducing power, total phenolic content, and total anti-oxidant capacity. The results showed that hot water (HW) extracts of GT contained high levels of phenolics and exerted an excellent anti-oxidative capacity; thus, these were used in the animal experiment. The male BALB/c mice were randomly divided into control group, acetaminophen (APAP) group, positive control group and two GT groups at low (GT-L) and high (GT-H) dosages. The results showed that mice treated with GT had significantly decreased serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). GT-H increased glutathione levels and the ratios of reduced glutathione and oxidized glutathione (GSH/GSSG) in the liver, and inhibited serum and lipid peroxidation. This experiment was the first to determine phenolic compounds, chlorogenic acid and luteolin-7-glucoside in HW extract of GT. In conclusion, HW extract of GT may have potential anti-oxidant capacity and show hepatoprotective capacities in APAP-induced liver damaged mice.

Immunohistochemical and molecular study on the protective effect of curcumin against hepatic toxicity induced by paracetamol in Wistar rats

Background

An overdose of paracetamol is a frequent reason for liver and renal toxicity and possible death and curcumin has hepatoprotective properties against liver damage. The exact mechanism of such protection is not clear. Therefore, this study was conducted to examine the molecular levels of the protective effect of curcumin on paracetamol overdose induced hepatic toxicity in rats.

Methods

Male Wistar rats were allocated into 4 groups. Control group, administered corn oil; curcumin group, administered curcumin (400 mg/kg BW daily intra-gastric) dissolved in corn oil; paracetamol group, administered corn oil with a single dose of paracetamol (500 mg/kg BW intra-gastric) and protective group, administered curcumin with a single dose of paracetamol. Curcumin was administered for 7 successive days, while paracetamol was administered at day six of treatment. Blood and liver tissues were collected for biochemical, histopathological, immunohistochemical and molecular examination.

Results

Serum analysis revealed an alteration in parameters of kidney and liver. A decrease in the antioxidant activity of liver was recorded in paracetamol group while curcumin administration restored it. Histopathological findings showed an extensive coagulative necrosis in hepatocytes together with massive neutrophilic and lymphocytic infiltration. Immunostaining of liver matrix metalloproteinase-8 (MMP-8) in paracetamol administered rats showed an increase in MMP-8 expression in the area of coagulative necrosis surrounding the central vein of hepatic lobules. Curcumin administration decreased MMP-8 expression in liver of paracetamol administered rats. Gene expression measurements revealed that paracetamol decreased the expression of antioxidant genes and increased the expression of interleukin-1β (IL-1β), IL-8, tumor necrosis factor-α (TNF-α) and acute phase proteins. Curcumin administration ameliorated paracetamol-induced alterations in genes expression of antioxidant and inflammatory cytokines.

Conclusion

The results clarified the strong protective effect of curcumin on paracetamol induced hepatic toxicity in rats at the immunohistochemical and molecular levels.

Curcumin Suppresses the Production of Pro-inflammatory Cytokine Interleukin-18 in Lipopolysaccharide Stimulated Murine Macrophage-Like Cells

Curcumin is a major bioactive compound of turmeric that exerts its anti-inflammatory effects by suppressing the many pro-inflammatory cytokines and chemokines in a number of cell types and pathologic conditions. Interleukin-18 (IL-18) is a novel pro-inflammatory cytokine which plays an important role not only in generating Th1 responses but also in inducing severe inflammatory reactions. As curcumin induced inhibition of IL-18 production in keratinocytes and mice is well known, effect of curcumin on IL-18 release in macrophages remains unknown. Hence, this present study has been designed to evaluate the effect of curcumin on IL-18 production and necrotic cell death in murine macrophages-like cells treated with or without lipopolysaccharide (LPS). The IL-18 secretion in cell culture supernatants was assayed by enzyme-linked immunosorbent assay and cytotoxicity was determined by lactate dehydrogenase release assay. Our results demonstrate that curcumin significantly inhibited the production of pro-inflammatory cytokine IL-18 in E.coli LPS stimulated murine macrophage-like cells RAW264.7 in a concentration-dependent manner. Interestingly, curcumin had no cytotoxic effect on murine macrophage-like cells. Our findings suggest that curcumin may be used as a potential therapeutic agent for the treatment of inflammatory diseases.

Aloe vera attenuated liver injury in mice with acetaminophen-induced hepatitis

BACKGROUND

An overdose of the acetaminophen causes liver injury. This study aims to examine the anti-oxidative, anti-inflammatory effects of Aloe vera in mice with acetaminophen induced hepatitis.

METHODS

Male mice were randomly divided into three groups (n = 8 each). Control group were given orally distilled water (DW). APAP group were given orally N-acetyl-P-aminophenol (APAP) 400 mg/kg suspended in DW. Aloe vera-treated group were given orally APAP and Aloe vera (150 mg/kg) suspended in DW. Twenty-four hours later, the liver was removed to determine hepatic malondialdehyde (MDA), hepatic glutathione (GSH), the number of interleukin (IL)-12 and IL-18 positive stained cells (%) by immunohistochemistry method, and histopathological examination. Then, the serum was collected to determine transaminase (ALT).

RESULTS

In APAP group, ALT, hepatic MDA and the number of IL-12 and IL-18 positive stained cells were significantly increased when compared to control group (1210.50 ± 533.86 vs 85.28 ± 28.27 U/L, 3.60 ± 1.50 vs 1.38 ± 0.15 nmol/mg protein, 12.18 ± 1.10 vs 1.84 ± 1.29%, and 13.26 ± 0.90 vs 2.54 ± 1.29%, P = 0.000, respectively), whereas hepatic GSH was significantly decreased when compared to control group (5.98 ± 0.30 vs 11.65 ± 0.43 nmol/mg protein, P = 0.000). The mean level of ALT, hepatic MDA, the number of IL-12 and IL-18 positive stained cells, and hepatic GSH in Aloe vera-treated group were improved as compared with APAP group (606.38 ± 495.45 vs 1210.50 ± 533.86 U/L, P = 0.024; 1.49 ± 0.64 vs 3.60 ± 1.50 nmol/mg protein, P = 0.001; 5.56 ± 1.25 vs 12.18 ± 1.10%, P = 0.000; 6.23 ± 0.94 vs 13.26 ± 0.90%, P = 0.000; and 10.02 ± 0.20 vs 5.98 ± 0.30 nmol/mg protein, P = 0.000, respectively). Moreover, in the APAP group, the liver showed extensive hemorrhagic hepatic necrosis at all zones while in Aloe vera-treated group, the liver architecture was improved histopathology.

CONCLUSIONS

APAP overdose can cause liver injury. Our result indicate that Aloe vera attenuate APAP-induced hepatitis through the improvement of liver histopathology by decreased oxidative stress, reduced liver injury, and restored hepatic GSH.