Thymoquinone treatment against acetaminophen-induced hepatotoxicity in rats

Phytochemical Analysis, and Antioxidant and Hepatoprotective Activities of Chamaerops humilis L. Leaves; A Focus on Xanthine Oxidase

Chamaerops humilis L. is clumping palm of the family Arecaceae with promising health-promoting effects. Parts of this species are utilized as food and employed in folk medicine to treat several disorders. This study investigated the phytochemical constituents of C. humilis leaves and their antioxidant and xanthine oxidase (XO) inhibitory activities in vitro and in vivo in acetaminophen (APAP)-induced hepatotoxicity in rats. The chemical structure of the isolated phytochemicals was determined using data obtained from UV, MS, IR, and 1H-, 13C-NMR spectroscopic tools as well as comparison with authentic markers. Eleven compounds, including tricin 7-O-β-rutinoside, vicenin, tricin, astragalin, borassoside D, pregnane-3,5,6,16-tetrol, oleanolic acid, β-sitosterol and campesterol were isolated from C. humilis ethanolic extract (CHEE). CHEE and the butanol, n-hexane, and dichloromethane fractions exhibited in vitro radical scavenging and XO inhibitory efficacies. The computational findings revealed the tendency of the isolated compounds towards the active site of XO. In vivo, CHEE ameliorated liver function markers and prevented tissue injury induced by APAP in rats. CHEE suppressed hepatic XO, decreased serum uric acid and liver malondialdehyde (MDA), and enhanced reduced glutathione (GSH), superoxide dismutase (SOD), and catalase in APAP-treated rats. CHEE ameliorated serum tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1β in APAP-treated rats. Thus, C. humilis is rich in beneficial phytochemicals that possess binding affinity towards XO. C. humilis exhibited potent in vitro antioxidant and XO inhibitory activities, and prevented APAP hepatotoxicity by attenuating tissue injury, oxidative stress and inflammation.

Protection against α-Amanitin-induced liver toxicity: Efficacy of pomegranate seed oil and black cumin oil

The consumption of mushrooms containing α-Amanitin (α-A) can lead to severe liver damage. In this study, toxicological experiments were conducted to confirm the protective effects of pomegranate seed oil (PSO) and black cumin oil (BCO) against α-A-induced hepatotoxicity. Rats exposed once to α-A (3 mg/kg bw, i.p.) or saline alone (0.1 ml, i.p.) were either left untreated or treated with PSO or BCO at a dose of 2 ml/kg bw/day by oral gavage on the same day, and the treatment was continued for 7 days. Serum aminotransferases (ALT and AST), alkaline phosphatase (ALP) and total protein levels were measured and the active caspase 3 (cl-caspase 3) was evaluated by western blotting in the liver. Serum ALT, AST and ALP levels tended to decrease in the α-A exposed group, but no statistically significant difference was found compared to the saline group (p > 0.05). PSO and BCO did not affect serum liver function tests in rats exposed to saline or α-A. α-A toxicity was demonstrated by a significant decrease in serum total protein level (p < 0.05), a significant increase in liver cl-caspase 3 expression (p < 0.05), and structural liver damage mainly characterized by mononuclear inflammation and steatosis. When α-A exposed rats were treated with BCO, the increase in cl-caspase 3 was not inhibited, on the contrary BCO increased cl-caspase 3 in healthy rats (p < 0.05). PSO significantly ameliorated α-A-induced cl-caspase 3 increase and inflammatory histopathology in the liver. Both PSO and BCO completely prevented α-A-induced protein degradation. The findings indicate that PSO and BCO may protect liver functions against α-A-induced hepatotoxicity, encouraging future comprehensive studies to test them at different doses and frequency.

Effects of gossypin on acetaminophen-induced hepatotoxicity in mice

Liver injury from paracetamol (acetaminophen) (APAP) is common worldwide. To prevent intoxication with a drug with high poisoning, treatment can be made possible with an easily accessible and harmless substance. This study aimed to investigate the hepatoprotective ef-fects of Gossypin (GOS) in mice exposed to an overdose of APAP -the possible mechanism of action. Specifically, serum [alanine aminotransferase (ALT), aspartate transaminase (AST), and hepatic biochemical parameters (glutathione (GSH), malondialdehyde (MDA) and super-oxide dismutase (SOD)] were evaluated. Protein and mRNA levels of inflammatory, apoptot-ic, and cytochrome factors, including TNF-α, IL-1β, IL-6, NF-kB, and CYP2E1, were ana-lyzed using real-time PCR. Pretreatment with GOS significantly reduced APAP-induced he-patic injury via oxidative stress. Along with potent antioxidant activity, GOS promoted APAP hepatic detoxification by regulating AST, ALT, GSH, MDA, and SOD activities and mRNA levels of the cytochrome CYP2E1 gene. The anti-inflammatory activity of GOS in-creases its production. TNF-α, IL-1β and IL-6, through possible NF-kB blockade, are also responsible for its hepatoprotective effect. Taken together, GOS has the potential to be devel-oped as a preventive agent to be administered to patients suffering from APAP overdose.

Interleukin-35 and Thymoquinone nanoparticle-based intervention for liver protection against paracetamol-induced liver injury in rats

Paracetamol (PAR) is a commonly used antipyretic and analgesic agent, but its excessive usage can induce liver damage and major health consequences. Interleukin-35 (IL-35) is utilized to treat immunological disorders, intestinal illness, arthritis, allergic disease, hepatitis, and cancer. Thymoquinone (THYO) is also effective against a wide range of disorders. Consequently, this study sought out to explore the ameliorative effects of IL-35 and THYO against PAR-induced hepatotoxicity in rats. Sixty male rats were separated into six groups (10 rats/group): I control (0.5 mL NaCl, 0.9%/rat via oral gavage); II (IL-35), and III (TYHO) received intraperitoneal (i.p) injection of IL-35 (200 ng/kg) or THYO (0.5 mg/kg), respectively. Group IV (PAR) received 600 mg/kg of PAR orally; V (PAR + IL-35) and VI (PAR + TYHO); rats received 600 mg/kg of PAR orally and i.p injection of IL-35 (200 ng/kg) or THYO (0.5 mg/kg), respectively. Administration of IL-35 or THYO markedly mitigated the increasing in the levels of liver parameters triggered by PAR and noticeable enhancement of antioxidant and immunological markers were observed. Additionally, IL-35 or THYO decreased TNF-α, NF-κB, IL-10, IL-6 and IFN-γ in contrast to the PAR control group. Moreover, levels of Capase-3, and cytochrome C were significantly reduced by THYO or IL35, while, levels of Bcl-2 were markedly increased. Furthermore, significant downregulation of IL1-β, TNF-α, TGF-β, and Caspas-3 genes, as well as significant upregulation of Bcl-2 and IL-10 expression were detected. In conclusion, IL-35 and THYO insulated liver from PAR toxicity by mitigating oxidative stress, tissue damage, inflammation, and apoptosis.

Dandelion Polysaccharides Ameliorate High-Fat-Diet-Induced Atherosclerosis in Mice through Antioxidant and Anti-Inflammatory Capabilities

Dandelion (Taraxacum officinale), a member of the Asteraceae (Compositae) family, is well known as the traditional medical plant. Dandelion polysaccharides, a natural active ingredient extracted from the dandelion, possess immune regulation, anti-inflammatory, antioxidant, and anti-aggregation properties. These properties suggest that dandelion polysaccharides might alleviate atherosclerosis. Using an ApoE-/- atherosclerotic mice model fed a high-fat diet, we investigated the impact and potential mechanism of dandelion polysaccharides on atherosclerosis. We observed that dandelion polysaccharides significantly reduced the levels of triglyceride, total cholesterol, and low-density lipoprotein-cholesterol in serum, while elevated the high-density lipoprotein-cholesterol level. Concomitantly, dandelion polysaccharides reduced the area of atherosclerotic lesions and necrotic core of the aortic sinus, and increased the collagen content. Mechanistic studies showed that dandelion polysaccharides were effective in reducing serum malondialdehyde levels while elevating the enzymatic activities of superoxide dismutase and glutathione peroxidase. Furthermore, dandelion polysaccharides reduced the expression of chemotactic factor Mcp-1 and pro-inflammatory cytokines (Tnf-α, Il-1β, and Il-6) in atherosclerotic lesions. Overall, these results indicated that dandelion polysaccharides may take an important part in the attenuation of atherosclerosis via its antioxidant and anti-inflammatory properties.

Dietary Thymoquinone Alone or Combined with Swimming Exercise Protect against Microcystin-LR-Induced Oxidative Injury in Mice

Microcystin-leucine-arginine (MCLR) is the most abundant cyanotoxin produced by cyanobacteria. It induces potent cytotoxicity through oxidative stress and DNA damage. Thymoquinone (TQ) is a natural nutraceutical antioxidant derived from black cumin (Nigella sativa). Physical exercise (EX) improves whole-body metabolic homeostasis. Therefore, this study examined the protective role of swimming exercise and TQ against MC-induced toxicity in mice. Fifty-six healthy adult male albino mice (25-30 g) were randomized into seven groups; group (I) was the negative control and received oral physiological saline for 21 days; group (II) received water EX for 30 min daily; group (III) was intraperitoneally injected with TQ (5 mg/kg daily, for 21 days); group (IV) was intraperitoneally administered MC (10 μg/kg daily, for 14 days) and acted as the positive toxic control; group (V) was treated with MC and water EX; group (VI) was injected with MC and TQ; finally, group (VII) was treated with MC with TQ and water EX. In comparison with the control group, the results showed hepatic, renal, and cardiac toxicity in the MCLR-treated group, indicated by a significant increase (p < 0.05) in serum levels of alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine transferase (ALT), cholesterol, lactate dehydrogenase (LDH), creatine kinase (CK), creatine kinase-myocardial band (CK-MB), urea, creatinine, interleukin-6, interleukin -1β, and tumor necrosis factor-α levels. In addition, there were significant elevations (p < 0.05) in malondialdehyde (MDA) and nitric oxide (NO) levels and a significant decrease in reduced glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD) in hepatic, cardiac, and renal tissues. Treatment with either TQ or water EX significantly improved (p < 0.05) the MC-induced toxicity with superiority of the TQ group in the restoration of normal ranges; however, cotreatment with both TQ and swimming EX showed the most improvement and restoration to normal ranges as a result of increasing EX clinical efficacy by TQ.

Thymoquinone supplementation mitigates arsenic-induced cytotoxic and genotoxic alterations in rat liver

Arsenic, a widespread environmental toxin, produces multiple organ toxicity, including hepatotoxicity. Thymoquinone (TQ) is known to restore liver functions in several hepatic injury models. This study aims to assess the mitigative potential of TQ against sodium arsenate (NaAs)-induced cytotoxic and genotoxic alterations in the liver. Rats were randomly distributed to control, NaAs, TQ, and NaAs+TQ groups. NaAs+TQ and TQ group of rats were pre-treated with TQ (1.5 mg/kg bwt, orally) for 14 days, and the treatment was further continued for 30 days, with and without NaAs treatment (5 mg/kg bwt, orally), respectively. The deleterious histological alterations in the liver of arsenic intoxicated animals were accompanied by an upsurge in the activities of serum ALT and AST, the diagnostic indicators of liver injury. NaAs caused pronounced alterations in the activities of membrane marker and carbohydrate metabolic enzymes and the enzymatic and non-enzymatic components of hepatic antioxidant defense. Significant hepatocyte DNA damage and hepatic arsenic accumulation were also observed in arsenic-exposed rats. TQ supplementation alleviated these adverse alterations and improved the overall hepatic metabolic and antioxidant status in NaAs-administered rats. Prevention of oxidative injury could be the key mechanism of TQ-elicited protective effects. TQ may have an excellent scope as a dietary supplement in the management of arsenic-induced hepatic pathophysiology.

Identification and functional characterization of a γ-terpinene synthase in Nigella sativa L (black cumin)

Nigella sativa (Black cumin) has many applications in food and pharmaceutical industries. Thymoquinone has been considered as a main effective compound in N. sativa seeds and attracted researchers' attention mainly due to its medicinal potential. In this study, the essential oil components of leaves, flowers and seed developmental stages including half black seeds, soft black seeds and hard black seeds were analyzed in N. sativa. Whereas no terpenes were detected in flowers and leaves, seeds showed an essential oil composition that increased in its thymoquinone content during seed maturation. To study the proposed first step of thymoquinone biosynthesis, the formation of γ-terpinene from geranyl diphosphate (GDP), we identified and functionally characterized a γ-terpinene synthase (NsTPS1) in N. sativa. This monoterpene synthase was identified in RNA sequence data derived from seeds. After heterologous expression in Escherichia coli, partially purified NsTPS1 converted GDP to γ-terpinene. NsTPS1 is the first functionally characterized terpene synthase from N. sativa and displays a higher similarity to other terpene synthases from Ranunculaceae than known γ-terpinene synthases from more distant plant species. Characterization of NsTPS1 elucidates the first dedicated step in the biosynthesis of thymoquinone in N. sativa and paves the way towards metabolic engineering for high-level thymoquinone production.

Development and biological evaluation of protective effect of kidney targeted N-acetylated chitosan nanoparticles containing thymoquinone for the treatment of DNA damage in cyclophosphamide-induced haemorrhagic cystitis

Thymoquinone (TQ), the most prominent constituent of Nigella sativa seeds, essential oil, is reported to possess an organ protective effect via Nrf2 expression and activation of Phase-II antioxidant enzymes. Haemorrhagic cystitis is the sudden onset of haematuria combined with bladder pain and irritable bladder symptoms are the known toxic effects of cyclophosphamide (CYP) chemotherapy. The objective of the present study was to investigate and compare the protective effect of thymoquinone (TQ) and thymoquinone nanoparticles (TQ-NP) in the kidney against CYP-induced haemorrhagic cystitis. Primarily, TQ-NP was fabricated by synthesis of N-acetylated chitosan and nanoparticle preparation by the ionic gelation technique. They were characterized by particle size, polydispersive index (PDI), zeta potential, entrapment efficiency (EE), SEM, and dynamic scattering calorimetry (DSC). Moreover, fluorescein isothiocyanate (FITC) labeled NPs were prepared for biodistribution studies. The protective mechanisms of TQ-NP included its anti-inflammatory activity, inhibitory effects on cytokine levels, and protection against the DNA damage in the bladder epithelium. The cystitis was induced in rats by orally administering 200 mg/kg of CYP. The dose-dependent protective effect of the TQ-NP was determined by intravenously administering 1, 2, and 5 mg/kg of the TQ-NP to CYP-treated rats. The present study revealed that the TQ-NP prepared by ionic gelation method provides kidney targeted delivery of TQ as compared to TQ solution. The mean particle size, PDI, and %EE of TQ-NP were 272.6 nm, 0.216, 70.81 ± 0.12% respectively. The zeta potential of thymoquinone-loaded nanoparticles was found to be -20.7 mV and - 22.6 mV respectively before and after lyophilization. SEM study also confirmed the small size and spherical shape. Pharmacokinetic studies revealed the improvement in half-life and prolonged action of the TQ-NP as compared to the TQ solution. Also, TQ-NP administration showed more protection against the characteristic histological alterations in the bladder in comparison to TQ solution. The present study indicates that TQ-NP exerts potent anti-oxidant, DNA protective and cytokine inhibitory activity at considerably lower concentrations as compared to plain TQ solution. The nano formulation of TQ using N-acetylated chitosan provides effective kidney targeted delivery of TQ, which in turn improves its retention and protective efficacy against CYP-induced haemorrhagic cystitis.

Hematological and biochemical investigations on the effect of curcumin and Thymoquinone in male mice exposed to Thioacetamide

Currently, living organisms are increasingly exposed to many toxic chemicals in the environment. These substances pose a threat to human life, other living organisms and ecosystem. In fact, there is an increasing requirement to search for safe therapeutic sources today. Medicinal plants and natural products have become of great importance globally because of their therapeutic potential and medicinal properties, as well as their availability and the absence of harmful side effects for most of them. The present study was designed to explore the potential protective effect of curcumin (CUR) and thymoquinone (TQ) in male rats exposed to thioacetamide (TAA). The experimental mice were divided into eight groups. Group 1 was served as control. Group 2 was exposed to 50 mg/ kg body weight of TAA. Group 3 was exposed to CUR and TAA. Mice of group 4 were treated with TQ and TAA. Mice of group 5 were exposed to CUR plus TQ and TAA. Group 6 was supplemented with CUR. Group 7 was subjected to TQ. Mice of group 8 were treated with CUR and TQ. Hematological and biochemical alterations were evaluated after one month. Significant increases of white blood corpuscles (WBC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TB), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) values were observed in group 2, while the values of red blood corpuscles (RBC), hemoglobin (Hb(, hematocrit (Hct), glutathione (GSH) and superoxide dismutase (SOD) were statistically decreased. Treatment with CUR, TQ and their combination inhibited the hematological and biochemical alterations induced by TAA toxicity. Moreover, the most protective effect was observed in mice treated with CUR plus TQ. These new results suggested that the protective effect of CUR and TQ attributed to their antioxidant properties.

Thymoquinone improves cognitive and hippocampal long-term potentiation deficits due to hepatic encephalopathy in rats

OBJECTIVES

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome that causes brain disturbances. Thymoquinone (TQ) has a wide spectrum of activities such as antioxidant, anti-inflammatory, and anticancer. This study aimed to evaluate the effects of TQ on spatial memory and hippocampal long-term potentiation (LTP) in rats with thioacetamide (TAA)-induced liver injury and hepatic encephalopathy.

MATERIALS AND METHODS

Adult male Wistar rats were divided into six groups randomly: 1) Control; 2) HE, received TAA (200 mg/kg); 3-5) Treated groups (HE+TQ5, HE+TQ10, and HE+TQ20). TQ (5, 10, and 20 mg/kg) was injected intraperitoneally (IP) for 12 consecutive days from day 18 to 29. Subsequently, spatial memory performance was evaluated by the Morris water maze paradigm and hippocampal LTP was recorded from the dentate gyrus (DG) region. Activity levels of Malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in the hippocampal tissue.

RESULTS

Data showed that the hippocampal content of MDA was increased while SOD activities were decreased in TAA-induced HE. TQ treatment significantly improved spatial memory and LTP. Moreover, TQ restored the levels of MDA and SOD activities in the hippocampal tissue in HE rats.

CONCLUSION

Our data confirm that TQ could attenuate cognitive impairment and improve LTP deficit by modulating the oxidative stress parameters in this model of HE, which leads to impairment of spatial cognition and LTP deficit. Thus, these results suggest that TQ may be a promising agent with positive therapeutic effects against liver failure and HE defects.

Therapeutic perspectives of the black cumin component thymoquinone: A review

The dietary phytochemical thymoquinone (TQ), belonging to the family of quinones, mainly obtained from the black and angular seeds of Nigella sativa, is one of the promising monoterpenoid hydrocarbons, which has been receiving massive attention for its therapeutic potential and pharmacological properties. It plays an important role as a chemopreventive and therapeutic agent in the treatment of various diseases and illnesses. The aim of this review is to present a summary of the most recent literature pertaining to the use of TQ for the prevention and treatment of various diseases along with possible mechanisms of action, and the potential use of this natural product as a complementary or alternative medicine. Research findings indicated that TQ exhibits numerous pharmacological activities including antioxidant, anti-inflammatory, cardioprotective, hepatoprotective, antidiabetic, neuroprotective, and anticancer, among others. Conclusions of this review on the therapeutic aspects of TQ highlight the medicinal and folk values of this compound against various diseases and ailments. In short, TQ could be a novel drug in clinical trials, as we hope.

The potential effect of phytochemicals and herbal plant remedies for treating drug-induced hepatotoxicity: a review

Drug-induced liver injury significantly caused by synthetic drugs, and other xenobiotics contribute to clinical hepatic dysfunction, which has been a substantial challenge for both patients and physicians. Traditional medicines used as an alternative therapy because of their pharmacological benefits, less or no side effects, and enormous availability in nature. Phytochemicals are essential ingredients of plants that reduce necrotic cell death, restore the antioxidant defence mechanism, limit oxidative stress, and prevent the inflammation of tissue and dysfunction of the mitochondria. In this review, we principally focused on the potential effect of the herbal plants and their phytochemicals in treating drug-induced hepatotoxicity.

Thymoquinone anticancer activity is enhanced when combined with royal jelly in human breast cancer

BACKGROUND

Breast cancer is the most common cause of the majority of cancer-related deaths in women, among which triple-negative breast cancer is the most aggressive type of breast cancer diagnosed with limited treatment options. Thymoquinone (TQ), the main bioactive constituent of Nigella sativa, has been extensively studied as a potent anticancer molecule against various types of cancers. Honeybee products such as the royal jelly (RJ), the nutritive secretion fed to honeybee queens, exhibit a variety of biological activities besides its anticancer effect. However, the anticancer activity of the combination of TQ and RJ against breast cancer is still unknown.

AIM

To investigate cytotoxicity of RJ in FHs 74 Int cells and the anticancer effects of TQ, RJ, and their combinations in the MDA-MB-231 cell line.

METHODS

Cells were treated with TQ, RJ, and their combinations for 24 h. Using 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, we determined the half-maximal inhibitory concentration of TQ. Trypan blue and 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays were then performed to assess the cell viability in response to different treatment conditions. Cell death and cycle regulation were investigated using propidium iodide deoxyribonucleic acid staining followed by flow cytometry in response to a single dose of TQ, RJ, and their combination. Immunostaining for cleaved caspase 3 and Ki67 expression was used to determine apoptosis induction and changes in cell proliferation.

RESULTS

TQ alone inhibited cell viability in a dose-dependent manner at concentrations below and above the half-maximal inhibitory concentration. RJ exhibited relatively nontoxic effects against MDA-MB-231 cells and FHs 74 Int small intestinal cells at concentrations below 5 µg/mL. High doses of RJ (200 µg/mL) had greater toxicity against MDA-MB-231 cells. Interestingly, the inhibition of cell viability was most pronounced in response to 15 µmol/L TQ and 5 µg/mL RJ. A dose of 15 µmol/L TQ caused a significant increase in the PreG1 population, while a more pronounced effect on cell viability inhibition and PreG1 increase was observed in response to TQ and RJ combinations. TQ was the main inducer of caspase 3-dependent apoptosis when applied alone and in combination with RJ. In contrast, no significant regulation of Ki67 expression was observed, indicating that the decrease in cell viability was due to apoptosis induction rather than to inhibition of cell proliferation.

CONCLUSION

This study is the first to report enhanced anticancer effects of TQ and RJ combination against MDA-MB-231 breast cancer cells, which could confer an advantage for cancer therapy.

Thymoquinone: A Promising Natural Compound with Potential Benefits for COVID-19 Prevention and Cure

COVID-19 has caused a major global health crisis, as excessive inflammation, oxidation, and exaggerated immune response in some sufferers can lead to a condition known as cytokine storm, which may progress to acute respiratory distress syndrome (ARDs), which can be fatal. So far, few effective drugs have emerged to assist in the treatment of patients with COVID-19, though some herbal medicine candidates may assist in the fight against COVID-19 deaths. Thymoquinone (TQ), the main active ingredient of black seed oil, possesses antioxidant, anti-inflammatory, antiviral, antimicrobial, immunomodulatory and anticoagulant activities. TQ also increases the activity and number of cytokine suppressors, lymphocytes, natural killer cells, and macrophages, and it has demonstrated antiviral potential against a number of viruses, including murine cytomegalovirus, Epstein-Barr virus, hepatitis C virus, human immunodeficiency virus, and other coronaviruses. Recently, TQ has demonstrated notable antiviral activity against a SARSCoV-2 strain isolated from Egyptian patients and, interestingly, molecular docking studies have also shown that TQ could potentially inhibit COVID-19 development through binding to the receptor-binding domain on the spike and envelope proteins of SARS-CoV-2, which may hinder virus entry into the host cell and inhibit its ion channel and pore forming activity. Other studies have shown that TQ may have an inhibitory effect on SARS CoV2 proteases, which could diminish viral replication, and it has also demonstrated good antagonism to angiotensin-converting enzyme 2 receptors, allowing it to interfere with virus uptake into the host cell. Several studies have also noted its potential protective capability against numerous chronic diseases and conditions, including diabetes, hypertension, dyslipidemia, asthma, renal dysfunction and malignancy. TQ has recently been tested in clinical trials for the treatment of several different diseases, and this review thus aims to highlight the potential therapeutic effects of TQ in the context of the COVID-19 pandemic.

Thymoquinone, extract from Nigella sativa seeds, protects human skin keratinocytes against UVA-irradiated oxidative stress, inflammation and mitochondrial dysfunction

Ultraviolet A (UVA) irradiation caused skin keratinocytes to accumulate reactive oxygen species (ROS) leading to the skin injury. Thymoquinone (TQ) was identified as the prominent bioactive ingredient in Nigella sativa seeds which was applied in therapying various human diseases. This study aimed to illustrate the role and mechanism of TQ in UVA-induced skin injury. We pre-treated HaCaT cells with TQ and irradiated them by UVA. MTT and Elisa assays were used to evaluate cell viability and apoptosis, as well as cytokine levels. To detect the related parameters of oxidative stress and mitochondrial function, colorimetry, spectrophotometry, bioluminescence, and dual-luciferase reporter methods were used. RT-qPCR and western blotting were performed for expressions of related mRNAs and proteins. TQ significantly improved the UVA-induced cytotoxicity on HaCaT cells. TQ treatment alleviated the oxidative stress and inflammation in UVA-irradiated keratinocytes. Besides, UVA irradiation promoted mitochondrial dysregulation in HaCaT cells leading to cell apoptosis, which could be reversed by TQ treatment. More importantly, NrF2/ARE pathway was activated in TQ-treated cells, while COX-2 was depressed, and inhibiting the pathway or activating COX-2 blocked the therapeutic effect of TQ on UVA-induced skin cell injury. Our study suggested that TQ treatment attenuated the UVA-induced oxidative and inflammatory responses, as well as mitochondrial apoptosis in keratinocytes by COX-2 inhibition via activating NrF2/ARE pathway. This might be a novel sight for preventing the solar radiation damage to the skin.

Structure-Odor Activity Studies on Derivatives of Aromatic and Oxygenated Monoterpenoids Synthesized by Modifying p-Cymene

Thymoquinone was recently reported as having a unique pencil-like odor and being the impact compound for the cedar-like and cedar wood-based product smell such as pencils. The compounds thymol and carvacrol are structurally related odorants commonly found in plants and foods such as thyme and oregano, also having a significant contribution to their overall aroma. However, a systematic elucidation of the sensory properties in this class of oxygenated, aromatic monoterpenoids has not been carried out. To close this gap and gain new insights into structure-odor relationships leading to pencil-like and woody odors, 19 structurally related derivatives of p-cymene starting from thymol and carvacrol were synthesized and characterized. The compounds had odor thresholds ranging from 2.0 ng/L air to 388.8 ng/L air, being lowest for thymol and carvacrol and highest for thymohydroquinone. The compounds smelled mostly thyme-like, oregano-like, and pencil-like with phenolic, earthy, and medicinal variations in their odor character, which could be successfully linked to structural motifs.

Apigenin alleviated acetaminophen-induced hepatotoxicity in low protein-fed rats: Targeting oxidative stress, STAT3, and apoptosis signals

Apigenin (API) is a natural flavonoid abundant in fruits and vegetables. The present study was undertaken to evaluate the effect of protein malnutrition (PMN) on acetaminophen (APAP)-induced hepatotoxicity, together with the protective effects of API, in male Wistar albino rats. In total, 64 male rats were divided into eight groups. Silymarin (SIL) (100 mg/kg, PO) as a reference standard and API (50 mg/kg, PO) were given to normal and APAP-induced hepatic injury in low protein-fed rats. The present results revealed that PMN significantly potentiated APAP-induced hepatotoxicity. Interestingly, the administration of SIL and API alleviated the induced damage, as revealed by reduced serum alanine aminotransferase and aspartate aminotransferase activities along with a significant improvement of the histopathological damage. API suppressed inflammatory response by reducing the interleukin-1β level and signal transducer and activator of transcription 3 expressions along with attenuating oxidative stress as shown by a significant reduction in liver contents of malondialdehyde and nitrite/nitrate as well as restoration of hepatic content of reduced glutathione and superoxide dismutase activity. API also counteracted apoptosis through downregulation of caspase-3 expression level. In conclusion, PMN greatly potentiated the hepatotoxic effects of APAP, and API produced a multimechanistic hepatoprotective activity that can be attributed to its antioxidant, anti-inflammatory, and antiapoptotic effects.

Hepatoprotective and antioxidant activity of hydroalcoholic extract of Stachys pilifera. Benth on acetaminophen-induced liver toxicity in male rats

Background

Acetaminophen (APAP) at high doses causes adverse side effects such as hepatotoxicity. The aim of the current study was to investigate the hepatoprotective and antioxidant effects of hydroalcoholic extract of Stachys pilifera. Benth (SP) on hepatotoxicity induced by APAP in male rats.

Methods

Adult male Wistar rats were allocated into four groups: control (C), APAP (2 g/kg), APAP + SP (500 mg/kg), and APAP + Silymarin (SM, 100 mg/kg) as positive control group. On the seventh day, the rats were sacrificed after taking blood samples. Then levels of biochemical parameters, oxidative stress markers and activity of antioxidant enzymes were measured.

Results

In the APAP group, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) enzymes activity was significantly increased and the level of protein carbonyl (PCO) was insignificantly increased as compared to control group. In addition, the activity of glutathione peroxidase (GPX) and total thiol in the APAP group was significantly decreased compared to the normal rats. Stachys pilifera. Benth extract administration significantly reduced the activity of AST and ALT enzymes and the level of PCO compared to the APAP group, while significantly elevated the activity of GPX enzyme.

Conclusion

Hydroalcoholic extract of SP diminishes hepatotoxicity induced by APAP by reducing the amount of liver function indicators (AST and ALT). Furthermore, the hydroalcoholic extract of SP is capable of reducing oxidative stress through inhibiting protein oxidation as well as boosting the activity of GPX enzyme. In this respect, the hepatoprotective impact induced by the SP extract may possibly be attributable to its reactive oxygen species scavenging and antioxidant properties.

Hepatoprotective and antioxidant activity of watercress extract on acetaminophen-induced hepatotoxicity in rats

Introduction

Acetaminophen (APAP) as an analgesic and antipyretic drug can result to liver damages while using more than 4 g/day. Therefore, APAP toxicity causes the liver to dysfunction. This study aims to investigate the hepatoprotective and antioxidant activity of hydroalcoholic extract of watercress (WC) in APAP-induced hepatotoxicity in rats.

Materials and methods

Randomly, twenty-four Wistar rats were divided into four groups of six each. Groups named as control, APAP, APAP + WC and APAP + S for group 1, 2, 3, and 4, respectively. Group 1 received distilled water 1 ml/kg for 7 days. In group 2, 3, and 4, rats pretreated by receiving distilled water (1 ml/kg), WC extract (500 mg/kg), silymarin extract (mg/kg) for 7 days, respectively. Of note, to induce acute hepatotoxicity in groups 2, 3, and 4, rats posttreated by orally intoxicated with single dose of APAP (2 g/kg) on the sixth day. The animals were sacrificed on the seventh day. Alanine amino transferase (ALT), aspartate amino transferase (AST), ferric reducing ability of plasma (FRAP), protein carbonyl (PCO), total thiol (T-SH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) activities were measured in plasma. It should be noted that the chemical composition of WC extract was identified by GC-MS analysis.

Results

The results have shown that there was a significant increase in AST, ALT, FRAP and PCO content in APAP group in comparison to control. Also, there was a significant reduction in T-SH levels and GPx activity in APAP group compared to control. However, administration of WC extract and silymarin not only causes a significant decrease in AST activity, but they markedly increased T-SH content and GPx activity compared to APAP group. GC-MS analysis showed the major compositions were found to be benzenepropanenitrile (48.30 %), Phytol (10.10 %), α-cadinene (9.50%) and linolenic acid (8.0).

Conclusions

It is concluded that the WC extract reduces APAP-induced toxicity through its hepatoprotective and antioxidant activity in rats.

Dissecting the roles of thymoquinone on the prevention and the treatment of hepatocellular carcinoma: an overview on the current state of knowledge

Thymoquinone (TQ) is the principal active monomer isolated from the seed of the medicinal plant Nigella sativa. This compound has antitumor effects against various types of cancer including hepatocellular carcinoma (HCC), mainly due to its anti-inflammatory and anti-oxidant properties. Several pre-clinical studies showed that TQ, through the modulation of different molecular pathways, is able to induce anti-apoptotic and anti-proliferative effects in HCC, without signs of toxicity. Moreover, it has been suggested that TQ has hepatoprotective effects by enhancing the tolerability and effectivity of neoadjuvant therapy prior to liver surgery, although the underlying mechanisms are not completely understood. Based on these findings, is assumable that TQ could represent a valuable therapeutic option for patients suffering from HCC. In this review, we summarize the potential roles of TQ in the prevention and treatment of HCC, by revising the preclinical studies and by highlighting the potential applications of TQ as a therapeutic choice for HCC treatment into clinical practices.

Piperine Enhances the Antioxidant and Anti-Inflammatory Activities of Thymoquinone against Microcystin-LR-Induced Hepatotoxicity and Neurotoxicity in Mice

Microcystin- (MC-) LR is the most frequent cyanotoxin produced by Microcystis aeruginosa cyanobacteria in the contaminated freshwater environment. MC represents a health hazard to humans and animals. Therefore, the present study was designed to evaluate the potential ameliorative effect of thymoquinone (TQ) and/or piperine (PP) against MC toxicity in mice. Fifty-six mice were randomly divided into seven experimental groups. Group I is the normal control that received distilled water for 21 days; Group II (TQ) was treated with TQ (10 mg/kg, i.p) for 21 days; Group III (PP) was treated with PP (25 mg/kg, i.p) for 21 days; Group IV (MC) was treated with MC (10 μg/kg, i.p) for 14 days and served as the toxic control; and Groups V, VI, and VII received TQ and/or PP 7 days prior to MC and continued for 14 days with MC. The results revealed that MC elicited hepatotoxicity and neurotoxicity which was evident due to the significant elevation of serum AST, ALT, γGT, ALP, LDH, IL-1β, IL-6, and TNF-α levels. Furthermore, MC markedly increased MDA and NO contents along with reduction of GSH, SOD, CAT, and GSH-Px in liver and brain tissues. The electron transport chain may be a possible target for MC. TQ and/or PP ameliorated the MC-mediated oxidative damage in the liver and brain which might be attributed to their antioxidant properties. However, the concurrent treatment of TQ and PP showed the best regimen as a result of the PP-enhanced bioavailability of TQ.

Thymoquinone Attenuates Acetaminophen Overdose-Induced Acute Liver Injury and Inflammation Via Regulation of JNK and AMPK Signaling Pathway

Thymoquinone (TQ) is a main aromatic component of Nigella sativa L. seeds or Agastache rugosa (Fisch. & C.A.Mey.) Kuntze. The protective mechanism of TQ against acute liver injury induced by acetaminophen (APAP), however, remains unclear. We aimed to investigated the hepato-protective mechanism of TQ on the development of APAP-induced acute liver injury. Male kunming mice were pretreated with TQ or N-acetylcysteine (NAC) before a single APAP injection. Human Chang liver cells were incubated with TQ, SP600125 or AICAR in presence of APAP for 24 h. TQ pretreatment reduced levels of serum aminotransferases and increased hepatic glutathione and glutathione peroxidase activities via inhibiting CYP2E1 expression. TQ inhibited JNK, ERK and P38 phosphorylation induced by APAP. Meanwhile, TQ inhibited PI3K/mTOR signaling activation and activated AMPK phosphorylation. Moreover, TQ prevented APAP-induced hepatocytes apoptosis regulated by Bcl-2 and Bax. Furthermore, TQ inhibited STAT3 phosphorylation on APAP-induced acute liver injury. In addition, TQ significantly inhibited P2X7R protein expression and IL-1 β release. APAP-enhanced JNK phosphorylation and APAP-suppressed AMPK phosphorylation were also observed in Chang liver cells, and these changes were recovered by pretreatment with TQ, SP600125 and AICAR. Our findings suggest that TQ may actively prevent APAP-induced acute liver injury, and the effect may be mediated by JNK and AMPK signaling pathways.

Thymoquinone, an Active Constituent of Black Seed Attenuates CCl4 Induced Liver Injury in Mice via Modulation of Antioxidant Enzymes, PTEN, P53 and VEGF Protein

AIM:

The present study was undertaken to evaluate the possible protective role of thymoquinone on CCl4-induced hepatotoxicity.

METHODS:

The activities of liver function enzymes and antioxidant enzymes were measured. Haematoxylin-Eosin staining was performed to analyze the live tissue alterations. Additionally, expression pattern of different proteins was evaluated through immunohistochemistry staining.

RESULTS:

The antioxidants enzymes activities were decreased significantly in the CCl4 induced group whereas recovery/increase of antioxidant enzymes was observed when thymoquinone was given to the mice. Moreover, thymoquinone administration significantly decrease the serum levels of alanine aminotransferase (ALT), alkaline phosphatase (ALP), and serum aspartate aminotransferase (AST). Liver tissue alterations were noted in CCl4 treated group whereas treatment with thymoquinone significantly prevented the CCl4-induced histological alteration. The expression of PTEN protein was high in CCl4 plus thymoquinone treated group while the loss of PTEN protein expression was observed in CCl4 treated group. Moreover, high expression of P53 protein was noticed in CCl4 treated the group as compared to CCl4 plus thymoquinone group. Difference in expression pattern of PTEN and p53 protein in CCl4 group and thymoquinone plus CCl4 treated group was statically significant (p < 0.05). Besides, expression of VEGF was high in CCl4 treated group as well as thymoquinone plus CCl4 treated group and difference in expression pattern was statically insignificant (p > 0.05).

CONCLUSION:

Our results suggest that thymoquinone can protect CCl4 induced liver damage and could be a preventive drug in the development of novel therapeutic agents for liver diseases.

Protective effects of Nigella sativa oil against carboplatin-induced liver damage in rats

OBJECTIVE

This study aimed to investigate the protective effects of nigella sativa oil (NSO) against liver damage due to intraperitoneal (i.p.) usage of carboplatin which is commonly used as a chemotherapeutic agent.

MATERIAL AND METHOD

Twenty four female Wistar-albino rats (about 200-350 grams each) were divided into 4 groups. Group 1 (n = 6) was administered 4 ml/kg intraperitoneal (i.p.) saline 48 and 24 h before. Group 2 (n = 6) was i.p. administered 4 ml/kg NSO 48 h before and 4 ml/kg saline 24 h before. Group 3 (n = 6) was i.p. administered 4 ml/kg saline 48 h before and 80 mg/kg carboplatin 24 h before. Group 4 (n = 6) was i.p. administered 4 ml/kg NSO 48 h before and 80 mg/kg carboplatin 24 h before. At the end of 48 h, all rats were sacrificed, and liver tissues were put into 10% neutral formalin. After the routine tissue follow-up, histopathological changes and collagen fiber density were evaluated with Hematoxylin-Eosin and Masson's Trichrome staining. Apoptotic index was determined with TUNEL staining.

RESULTS

The degeneration in hepatocytes, fiber distribution and density around central vein and portal space was observed in the carboplatin group compared to the control and NSO groups, hepatocyte cords preserved integrity, partial degeneration in hepatocytes and decreased collagen fiber distribution around central vein was noted in the NSO-carboplatin group compared to the carboplatin group. The apoptosis was lower in the NSO-carboplatin group compare with the carboplatin group, but no statistically significant difference was found between the two groups (p = 0.449).

CONCLUSION

When used NSO before carboplatin exposure, it may protect against liver damage.

Antioxidative stress effects of vitamins C, E, and B12, and their combination can protect the liver against acetaminophen-induced hepatotoxicity in rats

BACKGROUND

Several vitamins, including C, E, and B12, have been recognized as antioxidants and have shown hepatoprotective effects against the hepatotoxicity caused by acetaminophen (APAP) overdose. The current investigation aims to study the effect of these vitamins and their combination in protecting the liver from APAP hepatotoxicity in rats.

MATERIALS AND METHODS

An in vitro model of freshly isolated rat hepatocytes was utilized for assessing hepatocyte mitochondrial activity conducted by cell proliferation assay (MTT). The isolated hepatocytes were treated with vitamin C, vitamin E, vitamin B12 and their combination, with and without further addition of toxic concentrations of APAP. In addition, an in vivo experiment was carried out on Sprague Dawley rats treated intraperitoneally for 8 days with emulsions of the vitamins or their combination prior to injecting them with APAP.

RESULTS

In vitro results showed that vitamins C and B and the combination preparation significantly increased the percentage of hepatocyte mitochondrial activity, both with and without the addition of APAP (P<0.01). The mitochondrial activity in the isolated cultured hepatocytes was further enhanced with APAP addition. In vivo, the vitamins and their combination effectively reduced APAP-induced serum liver enzymes levels, namely ALT, AST, and ALP, and also attenuated oxidative stress and lipids peroxidation confirmed by the results of glutathione, superoxide dismutase, and maloondialdehyde.

CONCLUSION

Pretreatment with vitamins C, E, B12, or their combination was found to be beneficial in preventing in vivo hepatic oxidative stress induced by APAP overdose. Vitamin C on its own showed superior protection against APAP-induced liver injury in rats compared to the other vitamins. The proliferation of APAP-intoxicated liver cells in vitro was highest when protected with the vitamins' combination.

Diclofenac induced gastrointestinal and renal toxicity is alleviated by thymoquinone treatment

The aim of this study was to investigate whether thymoquinone (TQ) could alleviate diclofenac (DCLF)-induced gastrointestinal and renal toxicity in rats. Diclofenac was administered via intramuscular injection twice daily for 5 days and TQ was given by gavage for the same period. Hematological and biochemical profiles were measured with autoanalyzers while reactive oxygen/nitrogen species (ROS/RNS) generation and total antioxidant capacity (TAC) were assayed by standard kits. Tissue injuries were evaluated by microscopy and histopathological scoring. Diclofenac treatment caused kidney and liver function test abnormalities, reduced hematocrit and hemoglobin levels but increased WBC and platelet counts. Histopathological findings showed renal tubular damage, gastrointestinal lesions and increased fibrosis in DCLF treated rats. Thymoquinone administration, along with DCLF treatment, attenuated hematological test abnormalities and DCLF induced renal functional impairment as evident by significantly restored serum creatinine and blood urea nitrogen levels. Similarly, TQ treatment significantly alleviated liver function test abnormalities and decreased tissue injury in the stomach and duodenum. Diclofenac treatment caused increased ROS/RNS formation and decreased TAC in the kidney, stomach and duodenal tissue. Thymoquinone administration increased gastrointestinal and renal TAC in DCLF treated rats. These results indicate that TQ could ameliorate gastrointestinal and renal toxicity induced by high dose DCLF treatment.

Protective Effect of Gemfibrozil on Hepatotoxicity Induced by Acetaminophen in Mice: the Importance of Oxidative Stress Suppression

Purpose: Gemfibrozil (GEM) apart from agonist activity at peroxisome proliferator-activated receptor-alpha (PPAR-α) has antioxidant and anti-inflammatory properties. Accordingly, the present study was designed to investigate the protective effect of GEM on acute liver toxicity induced by acetaminophen (APAP) in mice.

Methods: In this study, mice divided in seven groups include, control group, APAP group, GEM group, three APAP groups pretreated with GEM at the doses of 25, 50 and 100 mg/kg respectively and APAP group pretreated with N-Acetyl cysteine. GEM, NAC or vehicle were administered for 10 days. In last day, GEM and NAC were gavaged 1 h before and 1 h after APAP injection. Twenty four hours after APAP, mice were sacrificed. Serum parameters include alanine aminotransferase (ALT), aspartate aminotransferase (AST) and liver tissue markers including catalase enzyme activity, reactive oxygen species (ROS), malondialdehyde and reduced glutathione (GSH) levels determined and histopathological parameters measured.

Results: GEM led to significant decrease in serum ALT and AST activities and increase in catalase activity and hepatic GSH level and reduces malondialdehyde and ROS levels in the liver tissue. In confirmation, histopathological findings revealed that GEM decrease degeneration, vacuolation and necrosis of hepatocytes and infiltration of inflammatory cells.

Conclusion: Present data demonstrated that GEM has antioxidant properties and can protect the liver from APAP toxicity, just in the same pathway that toxicity occurs by toxic ROS and that GEM may be an alternative therapeutic agent to NAC in APAP toxicity.

Plants and Surgery: The Protective Effects of Thymoquinone on Hepatic Injury-A Systematic Review of In Vivo Studies

Multimodal treatment concepts including liver transplantation for hepatocellular carcinoma (HCC), extended resection methods and neoadjuvant chemotherapy for colorectal liver metastasis significantly improve patients’ outcome. However, surgery-induced hepatic ischemia-reperfusion injury (IRI) and chemotherapy-associated hepatotoxicity result in hepatocellular damage and compromised liver function. Activation of common key pathways in ischemic liver and hepatotoxic injury results in oxidative stress, inflammatory responses and apoptosis causing organ damage. Controlling liver damage before and during surgery is essential for the postoperative outcome. Nigella sativa has a long tradition as a natural remedy. In the essential oil, Thymoquinone (TQ) was identified as the main component and responsible for most of the therapeutic effects. Therefore, this systematic review aimed to summarize the hepatoprotective effects of TQ and its potential suitability to improve surgical outcome by reducing surgical ischemic injury and hepatotoxicity of neoadjuvant chemotherapy. The key findings can be summarized as TQ having strong antioxidant, anti-inflammatory, antifibrotic, anti-/proapoptotic and anticarcinogenic effects. Almost no side effects were reported irrespective of a large dose range, suggesting a wide therapeutic window. These results give rise to the expectation that TQ could evolve to a novel powerful drug to reduce hepatic injury.

Polydatin protects against acetaminophen-induced hepatotoxicity in mice via anti-oxidative and anti-apoptotic activities

Polydatin protects against acetaminophen-induced hepatotoxicity in mice.

Thymoquinone attenuates hepatotoxicity and oxidative damage caused by diazinon: an in vivo study

Thymoquinone (TQ) is the main active constituent of Nigella sativa seeds. The objective of this study was to explore the protective effects of TQ on diazinon (DZN)-induced liver toxicity in the mouse model. The animals were divided into five groups of 6 each and treated intraperitoneally. Group 1 received the vehicle, group 2 was given 16 mg/kg DZN, group 3 received 5 mg/kg TQ, and groups 4 and 5 were treated with 1.25 and 5 mg/kg of TQ as well as 16 mg/kg DZN, respectively. Finally, butyrylcholinesterase (BChE), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) serum activity as well as nitric oxide (NO), lipid peroxidation (LPO), total antioxidant capacity (TAC), total thiol molecule (TTM), and histopathological experiments were evaluated in the liver samples. Our findings showed that DZN caused a significant increase in ALT (P < 0.01), AST (P < 0.001), ALP (P < 0.001) serum levels, LPO (P < 0.001) and NO (P < 0.001), the depletion of the TAC (P < 0.05) and TTM (P < 0.001), and structural changes in the liver tissue. Following TQ administration, a significant improvement was observed in the oxidative stress biomarkers in the liver tissue. In addition, our biochemical findings were correlated well to the histopathological examinations. In conclusion, the data from this study indicate that the administration of TQ may prevent liver damage by preventing free radical formation in animals exposed to DZN.

Functional Oil from Black Seed Differentially Inhibits Aldose-reductase and Ectonucleotidase Activities by Up-regulating Cellular Energy in Haloperidol-induced Hepatic Toxicity in Rat Liver

In this study, the effect of rate-limiting enzymes involved in degradation of hepatic adenosine and intracellular sorbitol was investigated in rats exposed to haloperidol (HAL) and treated with functional oil (FO), containing principal active phytochemicals from black seed. Animals were divided into six groups (n=10): Distilled water, HAL 15 mg/kg, pre-administration/HAL 15 mg/kg, co-administration/HAL 15 mg/kg, post-administration/HAL 15 mg/kg, FO 150 mg/kg. The results of this study revealed that the activities of ectonucleotidase and aldose-reductase were significantly increased in HAL-treated rats when compared with the control (p < 0.05). However, differential treatments (pre, co and post) with FO depleted the activities of these enzymes compared with HAL-treated rats. Furthermore, therapeutic HAL administration increased the levels of key hepatic biomarkers (ALT, AST, and ALP) and malondialdehyde level with a concomitant decrease in functional hepatic cellular ATP. However, differential treatment with FO increases hepatic ATP and non-enzymatic antioxidant status, with a concomitant decrease in the levels of malondialdehyde and liver biomarkers. Therefore, results of this finding underlined the importance of aldose-reductase and econucleotidase activities in HAL induced toxicity and suggest some possible mechanisms of action by which FO prevent HAL-induced hepatic toxicity in rats.

Nonionic surfactant based thymoquinone loaded nanoproniosomal formulation: in vitro physicochemical evaluation and in vivo hepatoprotective efficacy

CONTEXT

The present study was carried out to formulate thymoquinone proniosomal formulation (TQP) and evaluate their efficacy in methotrexate (Mtx) induced hepatotoxicity in rats.

OBJECTIVE

The objective of the study was to explore a new therapeutic approach focusing on hepatoprotective activity using thymoquinone proniosomal formulation.

MATERIAL AND METHODS

TQP was formulated using span60, cholesterol and phospholipid by film hydration technique. The animals were divided into six groups with five animals each receiving different treatments for 7 days. On the 8th day, rats were anesthetized with ether, blood samples were withdrawn, livers were dissected out for biochemical tests and histopathological examinations.

RESULTS AND DISCUSSION

The size of vesicle was found to be in the nanometric range with higher entrapment efficiency. The high entrapment efficiency is probably due to the lipophilic character of TQ. The morphological structure showed the outline and core of the well-identified spherical vesicle, and also displaying the retention of sealed vesicular structure. The release of TQ from developed formulation was found to be significantly higher compared to control. Mtx treated rats showed significant elevation in ALT, AST, ALP and TBARs, whereas, TQP treated group showed significant reduction.

CONCLUSION

The developed formulation (TQP) significantly inhibited the elevated levels of serum marker enzymes and showed improved histopathological deformities.

Protective effect of rutin in comparison to silymarin against induced hepatotoxicity in rats

Aim:

The aim of this study is to evaluate the hepatoprotective effect of rutin (RTN) in comparison to silymarin (SLM) against acetaminophen (APAP)-induced hepatotoxicity in rats.

Materials and Methods:

Male Wistar albino rats (n=24) of 3 months age were equally divided into four groups. Group 1 served as normal control. Hepatotoxicity was induced in the remaining three groups with administration of 500 mg/kg po APAP from day 1-3. Groups 2, 3, and 4 were subsequently administered orally with distilled water, 25 mg/kg of SLM, and 20 mg/kg of RTN, respectively, for 11 days. The mean body weights and biomarkers of hepatotoxicity were estimated on day 0, 4 (confirmation of toxicity), and 15 (at the end of treatment). Hematological parameters were evaluated on day 4 and 15. Antioxidant profile and adenosine triphosphatases (ATPases) were assessed at the end of the experiment. Liver tissues were subjected to histopathology and transmission electron microscopy after the sacrifice on day 15.

Results:

Antioxidant profile, ATPases, and hematological and sero-biochemical parameters were significantly altered, and histopathological changes were noticed in the liver of toxic control group. These changes were reversed in groups 3 and 4 that were administered with SLM and RTN, respectively.

Conclusion:

The results of the present investigation enunciated that SLM has potent hepatoprotective activity though the RTN was found superior in restoring the pathological alterations in paracetamol-induced hepatotoxicity in Wistar albino rats.

Protective Effect of Thymoquinone against Cyclophosphamide-Induced Hemorrhagic Cystitis through Inhibiting DNA Damage and Upregulation of Nrf2 Expression

Cyclophosphamide (CYP) induced hemorrhagic cystitis is a dose-limiting side effect involving increased oxidative stress, inflammatory cytokines and suppressed activity of nuclear factor related erythroid 2-related factor (Nrf2). Thymoquinone (TQ), an active constituent of Nigella sativa seeds, is reported to increase the expression of Nrf2, exert antioxidant action, and anti-inflammatory effects in the experimental animals. The present study was designed to explore the effects of TQ on CYP-induced hemorrhagic cystitis in Balb/c mice. Cystitis was induced by a single intraperitoneal injection of CYP (200 mg/kg). TQ was administered intraperitoneally at 5, 10 and 20 mg/kg doses twice a day, for three days before and three days after the CYP administration. The efficacy of TQ was determined in terms of the protection against the CYP-induced histological perturbations in the bladder tissue, reduction in the oxidative stress, and inhibition of the DNA fragmentation. Immunohistochemistry was performed to examine the expression of Nrf2. TQ protected against CYP-induced oxidative stress was evident from significant reduction in the lipid peroxidation, restoration of the levels of reduced glutathione, catalase and superoxide dismutase activities. TQ treatment significantly reduced the DNA damage evident as reduced DNA fragmentation. A significant decrease in the cellular infiltration, edema, epithelial denudation and hemorrhage were observed in the histological observations. There was restoration and rise in the Nrf2 expression in the bladder tissues of mice treated with TQ. These results confirm that, TQ ameliorates the CYP-induced hemorrhagic cystitis in mice through reduction in the oxidative stress, inhibition of the DNA damage and through increased expression of Nrf2 in the bladder tissues.

Protective effect of thymoquinone against lead-induced hepatic toxicity in rats

Lead (Pb) intoxication is a worldwide health problem which frequently affects the liver. This study was carried out to investigate the potential protective effect of thymoquinone (TQ), the major active ingredient of volatile oil of Nigella sativa seeds, against Pb-induced liver damage. Adult male rats were randomized into four groups: Control group received no treatment, Pb group was exposed to 2000 ppm Pb acetate in drinking water, Pb-TQ group was cotreated with Pb plus TQ (5 mg/kg/day, per orally), and TQ group receiving only TQ. All treatments were applied for 5 weeks. Results indicated that Pb exposure increased hepatic Pb content, damaged hepatic histological structure (necrotic foci, hepatic strands disorganization, hypertrophied hepatocytes, cytoplasmic vacuolization, cytoplasmic loss, chromatin condensation, mononuclear cell infiltration, congestion, centrilobular swelling), and changed liver function investigated by plasma biochemical parameters (AST, ALT, ALP, γ-GT, LDH). Pb treatment also decreased total antioxidant status level and increased lipid peroxidation in the liver. Supplementation with TQ remarkably improved the Pb-induced adverse effects without significantly reducing the metal accumulation in the liver. In conclusion, our results indicate, for the first time, a protective effect of TQ against Pb-induced hepatotoxicity and suggest that this component might be clinically useful in Pb intoxication.

The Effect of the Active Ingredient Thymoquinone on Flap Viability in Random Pattern Flaps in Rats

Thymoquinone (TQ) is a plant extract that has been shown to have antioxidant, anti-inflammatory, angiogenic, antimicrobial, and anticarcinogenic effects. The aim of this study is to research how the use of TQ affects flap viability. 42 rats were placed into 6 groups, with 7 rats in each. A 3 × 10 cm McFarlane flap model was used on the test animals. The sham group had used neither surgical nor TQ treatment. The control group had surgery but no treatment afterwards. The preoperative TQ group was given oral doses of 2 mg/kg. TQ for 10 days preoperatively with no treatment after the surgical procedure. The postoperative TQ group received oral doses of 2 mg/kg TQ for 10 days after the surgical process. The preoperative + postoperative (pre + postoperative) TQ group was given oral doses of 2 mg/kg TQ for 10 days both preoperatively and postoperatively. Finally, the dimethylsulfoxide group received 10 mg/kg dimethylsulfoxide (DMSO) for 10 days both preoperatively and postoperatively. Ten days after surgery the findings were evaluated. The average rates of necrosis were found to be 29.7 % in the control group, 19.18 % in the preoperative TQ group, 13.05 % in the postoperative TQ group, 8.42 % in the pre + postoperative TQ group, and 29.03 % in the DMSO group. The experimental groups had better area measurement, histopathological, and electron microscopic results than the control group (All; p < 0.05). We believe that, because of its antioxidant, anti-inflammatory, and angiogenic properties, thymoquinone is an agent that can prevent ischemia-reperfusion damage and, therefore, prevent necrosis.

Protective Mechanisms of Thymoquinone on Methotrexate-induced Intestinal Toxicity in Rats

Background:

Intestinal toxicity is a serious side effect in methotrexate (MTX) chemotherapy.

Objective:

To investigate the mechanisms by which the anticancer drug MTX-induced intestinal damage could be prevented by thymoquinone (TQ), an active ingredient of Nigella sativa.

Materials and Methods:

TQ was given orally for 10 days, and MTX toxicity was induced at the end of day 3 of the experiment, with or without TQ pretreatment.

Results:

MTX caused intestinal damage, represented by distortion in normal intestinal histological structure, with significant oxidative stress, exhibited as decrease in reduced glutathione concentration and catalase activity, along with significant increase in malondialdehyde level compared to control group. MTX also caused nitrosative stress evident by increased intestinal nitric oxide (NO) level, with up-regulation of inducible NO synthase expression shown in immunohistochemical staining. Furthermore, MTX caused inflammatory effects as evident by up-regulation of intestinal necrosis factor-kappa beta and cyclooxygenase-2 expressions, which were confirmed by increased intestinal tumor necrosis factor-alpha level via enzyme-linked immunosorbent assay. Moreover, MTX caused apoptotic effect, as it up-regulated intestinal caspase 3 expression. Concomitant TQ significantly reversed the MTX-induced intestinal toxic effects by reversing intestinal microscopic damage, as well as significantly improving oxidative/nitrosative stress, inflammatory and apoptotic markers tested compared to MTX alone.

Conclusion:

TQ may possess beneficial intestinal protective effects as an adjuvant co-drug against MTX intestinal toxicity during cancer chemotherapy. TQ protection is conferred via antioxidant, anti-nitrosative, anti-inflammatory, and anti-apoptotic mechanisms.

SUMMARY

Methotrexate induces oxidative and nitrosative stress in intestinal tissues

Methotrexate also initiates inflammatory and apoptotic intestinal injury

Thymoquinone co-administration ameliorates methotrexate-induced intestinal toxicity

Thymoquinone has antioxidative, anti-nitrosative, anti-inflammatory, and anti-apoptotic mechanisms.

Abbreviations used: COX-2: Cyclooxygenase-2, ELISA: Enzyme-linked immunosorbent assay, H and E: Hematoxylin and eosin, iNOS: Inducible nitric oxide synthase, MDA: Malondialdehyde, MTX: Methotrexate, NO: Nitric oxide, NF-κB: Nuclear factor-κB, GSH: Reduced glutathione, TQ: Thymoquinone, TNF-α: Tumor necrosis factor-alpha

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.

Evaluation of kudzu root extract-induced hepatotoxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Kudzu root, the root of Pueraria lobata (Willd.) Ohwi, has been used as food and medicine for centuries, but few studies indicate that kudzu root may cause liver damage.

AIM OF STUDY

We studied the hepatotoxicity of kudzu root extract in mice, HepG2 cells and mice hepatocytes.

MATERIALS AND METHODS

Mice were administrated with kudzu root extract (10mg/day) for 4 weeks, and then the biochemical analysis and histopathological changes were carried out. To explore the potential mechanism by which kudzu root extract-induced hepatotoxicity, HepG2 cells and mice hepatocytes were co-cultured with kudzu root extract or puerarin, which is a kudzu root isoflavone, for 2h.

RESULTS

The increase of serum ALT and AST and histopathological changes in treated mice revealed that kudzu root extract was hepatotoxic. The increase of LDH leakage for HepG2 cells and mice hepatocytes further confirmed hepatotoxicity of kudzu root extract. Kudzu root extract and puerarin significantly up-regulated Mt1 mRNA involved in the acute phase response and Bax which is crucial for apoptosis. Gclc, Nrf2 and Ho-1 mRNA expressions did not change in treatment group.

CONCLUSIONS

Kudzu root extract may be hepatotoxic and caution may be required for its use.

Mechanisms of Thymoquinone Hepatorenal Protection in Methotrexate-Induced Toxicity in Rats

To investigate mechanisms by which thymoquinone (TQ) can prevent methotrexate- (MTX-) induced hepatorenal toxicity, TQ (10 mg/kg) was administered orally for 10 days. In independent rat groups, MTX hepatorenal toxicity was induced via 20 mg/kg i.p. at the end of day 3 of experiment, with or without TQ. MTX caused deterioration in kidney and liver function, namely, blood urea nitrogen, creatinine, alanine aminotransferase, and aspartate aminotransferase. MTX also caused distortion in renal and hepatic histology, with significant oxidative stress, manifested by decrease in reduced glutathione and catalase, as well as increase in malondialdehyde levels. In addition, MTX caused nitrosative stress manifested by increased nitric oxide, with upregulation of inducible nitric oxide synthase. Furthermore, MTX caused hepatorenal inflammatory effects as shown by increased tumor necrosis factor-α, besides upregulation of necrosis factor-κB and cyclooxygenase-2 expressions. MTX also caused apoptotic effect, as it upregulated caspase 3 in liver and kidney. Using TQ concurrently with MTX restored kidney and liver functions, as well as their normal histology. TQ also reversed oxidative and nitrosative stress, as well as inflammatory and apoptotic signs caused by MTX alone. Thus, TQ may be beneficial adjuvant that confers hepatorenal protection to MTX toxicity via antioxidant, antinitrosative, anti-inflammatory, and antiapoptotic mechanisms.

The effect of thymoquinone treatment on the combined renal and pulmonary toxicity of cisplatin and diesel exhaust particles

Particulate air pollution (PAP) exposure is associated with increased morbidity and mortality, particularly in patients with renal disease. However, there are only a few studies on the interaction between PAP and renal injury, and none on agents that may ameliorate it. We studied the interaction between cisplatin (CP) nephrotoxicity and a single exposure to diesel exhaust particle (DEP) in rats 24 h before sacrifice, and assessed the effect of co-treatment with the active ingredient in Nigella Sativa seed oil, thymoquinone (TQ) thereon. Rats were injected intraperitoneally with CP (6 mg/kg) and four days later, they were exposed intratracheally to DEP (0.5 mg/kg), and were sacrificed 24 h later. Oral TQ (20 mg/kg) was given daily throughout the experimental period. CP alone caused several physiological, biochemical, and histopathological changes that included reduced growth and creatinine clearance, and raised plasma neutrophil gelatinase-associated lipocalin (NGAL), interleukin 6 (IL-6) and C-reactive protein (CRP), creatinine and urea concentrations, and urinary N-acetyl-b-D-glucosaminidase (NAG) activities. It adversely affected several indices of oxidative damage in the kidneys, and induced renal tubular necrosis. Most of these actions were significantly potentiated in rats given both CP and DEP. TQ significantly abrogated many of the effects of CP and DEP, given alone and in combination. These results provide experimental evidence that subjects with renal diseases can be at higher risk from PAP, and that TQ, pending further pharmacological and toxicological studies, can be considered a useful agent in patients with renal diseases and exposed to PAP.