Protective effect of N-acetylcysteine on cyclophosphamide-induced cardiotoxicity in rats

A new perspective in the prevention and treatment of antitumor therapy-related cardiotoxicity: Intestinal microecology

The continuous development of antitumor therapy has significantly reduced the mortality of patients with malignancies. However, the antitumor-related cardiotoxicity has become the leading cause of long-term mortality in patients with malignancies. Besides, the pathogenesis of antitumor-related cardiotoxicity is still unclear, and practical means of prevention and treatment are lacking in clinical practice. Therefore, the major challenge is how to combat the cardiotoxicity of antitumor therapy effectively. More and more studies have shown that antitumor therapy kills tumor cells while causing damage to sensitive tissues such as the intestinal mucosa, leading to the increased permeability of the intestine and the dysbiosis of intestinal microecology. In addition, the dysbiosis of intestinal microecology contributes to the development and progression of cardiovascular diseases through multiple pathways. Thus, the dysbiosis of intestinal microecology may be a potential mechanism and target for antitumor-related cardiotoxicity. We summarized the characteristics of intestinal microecology disorders induced by antitumor therapy and the association between intestinal microecological dysbiosis and CVD. And on this basis, we hypothesized the potential mechanisms of intestinal microecology mediating the occurrence of antitumor-related cardiotoxicity. Then we reviewed the previous studies targeting intestinal microecology against antitumor-associated cardiotoxicity, aiming to provide a reference for future studies on the occurrence and prevention of antitumor-related cardiotoxicity by intestinal microecology.

Levocetrizine attenuates cyclophosphamide-induced lung injury through inhibition of TNF-α, IL-1β, TGF-β and MMP-9

Cyclophosphamide (CP) is an antineoplastic drug commonly used worldwide. Despite its spread, it causes fatal organ toxicity. Lung toxicity is a serious side effect of CP. Actually, in the past three years the world has been facing an un-predicted crisis following COVID-19 pandemic and the associated high-mortality rates attributed to respiratory distress. Accordingly; this study aimed to probe the potential prophylactic role of levocetrizine against CP-induced lung injury. Animals were allocated into three sets; control; CP and CP/Levo. CP was intraperitoneally injected in rats 150 mg/kg once on day 7. Levocetrizine was given orally for 14 days starting 7 days before CP injection. On the last day, all rats were sacrificed and lung tissues were kept for analysis. CP significantly elevated lung/body weight index, inflammatory cell counts, LDH, total protein, TNF-α, IL-1β, TGF-β and histamine levels in bronchoalveolar lavage (BAL). Moreover, it markedly increased expression of MMP-9 and contents of MDA, hydroxyproline, collagen and NOx besides decreasing GSH level and SOD activity in lung tissues. These biochemical results were further confirmed by histopathological examination. In contrast, treatment with levocetrizine significantly attenuated CP-induced pathological alterations. These findings propose that levocetrizine can attenuate CP-induced lung injury via exerting antioxidant, anti-inflammatory and anti-fibrotic effects.

Selenium protection from DNA damage and regulation of apoptosis signaling following cyclophosphamide induced cardiotoxicity in rats

We investigated the mechanism of the cardioprotective effect of selenium (Se) against cyclophosphamide (CPA) induced cardiotoxicity in rats. We divided 24 female Wistar albino rats into four groups. The control group was injected intraperitoneally (i.p.) with normal saline. The CPA group was injected i.p. with 200 mg/kg CPA. The Se group was injected i.p. with 1 mg/kg Se. The CPA + Se group was injected i.p. with 200 mg/kg CPA and 1 mg/kg Se. Rats were euthanized 24 h after injection and heart tissues were harvested. Histopathological examination revealed reduced severity of myocardial lesions in the CPA + Se group compared to CPA induced cardiotoxicity of the CPA group; this finding was confirmed by increased immunoreactivity of cardiac troponin-I (cTn-I) in the CPA + Se group compared to decreased cTn-I immunoreactivity in the CPA group. Administration of CPA increased the immunoreactivity of phosphorylated histone-2AX (γH2AX). Se reduced the CPA induced increase in γH2AX immunoreactivity. Se administration reversed the CPA induced increase of Bax and decrease of Bcl2 gene expressions. Our findings suggest that Se is cardioprotective by reducing DNA damage and regulating the genes responsible for apoptosis caused by CPA in rats.

1H NMR-based urinary metabolic analysis of high-dose cyclophosphamide-induced toxicity in mice

Cyclophosphamide (CP) is widely used in clinical fields. Beside its therapeutic effects, CP shows toxicity depending on dose and administration schedule. In this study, the urinary metabolic profiles were investigated in mice intraperitoneally injected with high-dose CP (150 mg/kg body weight) once a week over four weeks using nuclear magnetic resonance (NMR)-based metabolomics. Twenty-six metabolites were identified as potential biomarkers by multivariate statistical analysis. A decrease in isoleucine, alanine, N-acetylglutamic acid, proline, methionine, valine, phenylacetylglulamine, dimethylamine, hippurate, acetic acid, lactate, α-oxoglutarate, citrate, malonic acid, creatinine, niacin, β-hydroxybutyrate, and betaine, whereas an increase in leucine, glutamate, glycine, taurine, phenylacetylglycine, glucose, creatine, and choline were observed in the urine of high-dose CP-treated mice. Metabolites related to amino acid metabolism, energy metabolism, and gut microbial metabolism were changed markedly in the urine. Further metabolic pathway analysis suggested that seven metabolic pathways, including alanine, aspartate, and glutamate metabolism, arginine biosynthesis, glyoxylate, and dicarboxylate metabolism, glycine, serine and threonine metabolism, d-glutamine and d-glutamate metabolism, arginine, and proline metabolism, citrate cycle, as well as the gut microbiota metabolism, were significantly involved in response to high-dose CP treatment. These findings help to predict the toxicity of CP and understand the biological mechanism of the toxicity of CP.

Cardiotoxicity in autologous haematopoietic stem cell transplantation for systemic sclerosis

Autologous haematopoietic stem cell transplantation is now well-established as an effective treatment for severe systemic sclerosis with clear demonstration of favourable end-organ and survival outcomes. Treatment-related cardiotoxicity remains the predominant safety concern and contraindicates autologous haematopoietic stem cell transplantation in patients with severe cardiopulmonary disease. In this review, we describe the cardiovascular outcomes of autologous haematopoietic stem cell transplantation recipients, discuss the potential mechanisms of cardiotoxicity and propose future mitigating strategies.

Cardiovascular Complications in Hematopoietic Stem Cell Transplanted Patients

Hematopoietic stem cell transplantation (HSCT) is the only curative treatment for many patients suffering from hematologic malignancies, solid tumors, inborn errors of metabolism or genetic disorders. Despite decades of successful HSCT, clinical outcomes are still far from satisfactory due to treatment-related complications, including graft-versus-host disease (GvHD) and cardiovascular complications (CVC). CVC may affect patients in the acute period post-HSCT; however, the occurrence is far higher among long-term survivors. Induction treatment using cardiotoxic treatments, e.g., anthracyclines and radiotherapy, conditioning regimens containing cyclophosphamide, and post-HSCT comorbidities, including GvHD, are factors contributing to CVC. Cardiac function evaluation prior to and post-transplantation is an important strategy for choosing the proper conditioning regimen, HSCT protocol and post-HSCT supportive care. Cardiac systolic function evaluation by echocardiography, in addition to serum cardiac biomarkers, such as troponins and brain natriuretic peptides, is recommended as a routine follow-up for HSCT patients. Angiotensin-converting enzyme inhibitors, angiotensin-II-receptor blockers, and beta-blockers, which are mostly used for the treatment of chemotherapy-induced cardiotoxicity, might be used as treatments for HSCT-related CVC. In summary, the present review reveals the urgent need for further investigations concerning HSCT-related CVC both at the preclinical and clinical levels due to the lack of knowledge about CVC and its underlying mechanisms.

Ameliorative effect of flavocoxid on cyclophosphamide-induced cardio and neurotoxicity via targeting the GM-CSF/NF-κB signaling pathway

Cyclophosphamide (Cyclo) is a chemotherapeutic agent used as an immunosuppressant and as a treatment for many cancerous diseases. Many previous pieces of literature proved the marked cardio and neurotoxicity of the drug. Thus, this research provides evidence on the alleviative effect of flavocoxid on the cardiac and brain toxicity of cyclophosphamide in mice and determines its underlying mechanisms. Flavocoxid (Flavo) is a potent antioxidant and anti-inflammatory agent that inhibits the peroxidase activity of cyclooxygenase (COX-1 and COX-2) enzymes and 5-lipooxygenase (5-LOX). Flavo was administered orally (20 mg/kg) for 2 weeks, followed by Cyclo (100 mg/kg, i.p.) on day 14. Higher heart and brain weight indices, serum lactate dehydrogenase (LDH), creatine kinase (CK-MB), and nitric oxide (NO) were mitigated following Flavo administration. Flavo modulated oxidative stress biomarkers (malonaldehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD)), tumor necrosis factor-α (TNF-α), and interleukin (IL)-1β. Additionally, cardiac troponin I (cTn-I), nuclear factor kappa B (NF-κB), brain amyloid precursor protein (APP), and granulocyte macrophage colony-stimulating factor (GM-CSF) were decreased by Flavo administration. Moreover, Flavo ameliorated heart and brain histopathological changes and caspase-3 levels. Collectively, Flavo (20 mg/kg) for 14 days showed significant cardio and neuroprotective effects due to its antioxidant, anti-inflammatory, and antiapoptotic activities via modulation of oxidative stress, inflammation, and the GM-CSF/NF-κB signaling pathway.

Aspirin Protective Effect on Cyclophosphamide Induced Hematological Toxicity

Bone marrow toxicity is the most important factor limiting the use of cytotoxic drugs like alkylating agents in cancer treatment. Recently PG synthase enzyme inhibitors have been reported to potentiate the cytotoxic effects of these agents on cancer cells but little is known if they can affect the toxicity of these agents on bone marrow or other  tissues. Cyclophosphamide is one of the most commonly used alkylating agent. In the present work, the effect of these PG synthase enzyme inhibitors, aspirin on cyclophosphamide myelotoxicity was determined employing the peripheral blood count to reflect bone marrow injury. The effect on body weight changes caused by cyclophosphamide was also determined. Cyclophosphamide in doses of 25, 50 and 75 mg/kg i. v. produced as a dose dependent reduction in total WBC count, granulocyte, non granulocyte, and Hb% which was maximum on second day after injection and still present on 5th day post injection. It also produced a dose dependent reduction in body weight on day 5 after injection. Aspirin in doges of 75, 150 and 300 mg/kg i. m. protected against the reduction in WBC counts 'measured for 5 days after injection of cyclophosphamide (50 mg/kg). This protection was not dose dependent, though it was more optimum with 300 mg/kg and disappeared largely when a dose of 450 mg/kg was used. Aspirin did not prevent the changes in Hb% but retard the reduction in body weight caused by cyclophosphamide. It is concluded that aspirin can help to reduce injury and enhance recovery from bone marrow toxicity caused by cytotoxic agents such as the alkylating drugs cyclophosphamide for which no specific antidote is available. Aspirin produces this effect possibly by eliminating the harmful inhibitory effect of excess PGs or leukotrienes, released by bone marrow injury on growth factors of haemopoietic progenitor cells. The magnitude of this protection on WBC counts does not seem to differ between either PG synthase enzyme inhibitors or steroids when used alone or in combination although a synergistic effect in protecting erythropoiesis is observed.

Effect of a Low Dose of Carvedilol on Cyclophosphamide-Induced Urinary Toxicity in Rats—A Comparison with Mesna

One of the major side effects of cyclophosphamide (CPX)—an alkylating anticancer drug that is still clinically used—is urotoxicity with hemorrhagic cystitis. The present study was designed to evaluate the ability of carvedilol to protect rats from cyclophosphamide-induced urotoxicity. Rats were injected intraperitoneally (i.p.) with CPX (200 mg/kg) and administered carvedilol (2 mg/kg) intragastrically a day before, at the day and a day after a single i.p. injection of CPX, with or without mesna (40, 80, and 80 mg/kg i.p. 20 min before, 4 h and 8 h after CPX administration, respectively). Pretreatment with carvedilol partly prevented the CPX-induced increase in urinary bladder and kidney index, and completely protects from CPX-evoked alterations in serum potassium and creatinine level, but did not prevent histological alterations in the urinary bladder and hematuria. However, carvedilol administration resulted in significant restoration of kidney glutathione (GSH) level and a decrease in kidney interleukin 1β (IL-1β) and plasma asymmetric dimethylarginine (ADMA) concentrations. Not only did mesna improve kidney function, but it also completely reversed histological abnormalities in bladders and prevented hematuria. In most cases, no significant interaction of carvedilol with mesna was observed, although the effect of both drugs together was better than mesna given alone regarding plasma ADMA level and kidney IL-1β concentration. In conclusion, carvedilol did not counteract the injury caused in the urinary bladders but restored kidney function, presumably via its antioxidant and anti-inflammatory properties.

Oral N-acetylcysteine as an adjunct to standard medical therapy improved heart function in cases with stable class II and III systolic heart failure

BACKGROUND

This research attempted to assess whether N-acetylcysteine (NAC) as adjunctive therapy can be useful in the treatment of patients with heart failure (HF).

METHODS

Fifty-five cases with diagnosed systolic HF and stable symptomatic New York Heart Association (NYHA) functional class II and III and on optimal medical treatment of HF for at least 3 months were assigned for receiving oral NAC (600 mg twice daily) or placebo for 12 weeks. The outcomes were changes in the echocardiographic hemodynamic indices as well as the patients' functional capacity assessed by NYHA classification over a 12-week treatment.

RESULTS

Compared to placebo, NAC more significantly improved the systolic left ventricular (LV) function expressed as the ejection fraction and Tei index. These changes are accompanied by more improvement in other LV echocardiographic indices including LV end-diastolic volume index and LV global longitudinal strain in the patients receiving NAC in comparison with those receiving placebo. In parallel with the improvement of LV function, right ventricular (RV) function expressed as RV fractional area change and RV Tei-index also got more improvement in those receiving NAC than those receiving placebo. However, the change in RV global longitudinal strain did not show a significant difference between study groups. Additionally, at week 12, the distribution of the NYHA functional class also shifted toward a better outcome in the NAC group in comparison with the placebo group; however, it was not significant.

CONCLUSIONS

These preliminary data support experimental findings showing that NAC supplementation is able to improve heart function.

TRIAL REGISTRATION

The registration of the trial was done at the Iranian Registry of Clinical Trials ( www.irct.ir ). Identifier code: IRCT20120215009014N333. Registration date: 2020-01-11.

Protective effect of Apelin-13 in a cyclophosphamide-induced cardiorenal toxicity model in rats

Cyclophosphamide is a chemotherapeutic drug that is widely used in the clinic and can cause multi-organ toxicity. Apelin-13 is an endogenous adipocytokine with antioxidant properties. Therefore, this study aimed to investigate the possibility of apelin-13 being a potential therapeutic agent on cardiac toxicity and nephrotoxicity caused by cyclophosphamide. In this study, a total of 4 groups were formed, including 8 rats in each group. Group 1: The control group was administered only saline (ip). Group 2: Cyclophosphamide, a single dose of 200 mg/kg (ip) on day 7. Group 3: Apelin-13 (15 μg/kg), for 7 days (ip). Group 4: Administering apelin-13 (15 μg/kg) (ip) for 7 days and a single dose of cyclophosphamide (200 mg/kg) (ip) on day 7, the rats were sacrificed on day 8. LDH, cTn1, cK-Mb, AST, ALT, ALP, MDA, creatinine, and BUN were found to be high in the cyclophosphamide group, however, these values were reduced with apelin-13 administration. Antioxidant enzymes such as SOD, GPx, CAT, and GSH decreased in the cyclophosphamide group, apelin-13 increased these enzyme activities. In addition, histopathological examinations also supported the results obtained. The findings of this study showed that apelin-13 has a protective effect against cardiorenal toxicity caused by cyclophosphamide.

Protection by ginseng saponins against cyclophosphamide-induced liver injuries in rats by induction of cytochrome P450 expression and mediation of the l-arginine/nitric oxide pathway based on metabolomics

Ginseng saponins (GS) are the main active compounds in Panax ginseng and have been proven to be highly effective in attenuating the side effects of chemotherapy. However, there have been no reports on the mechanism of action of GS. Treatment with GS has certain benefits, including decreasing the toxicity levels in the liver [alanine aminotransferase (ALT), albumin (ALB), alkaline phosphatase (ALP), aspartate transaminase (AST)], reducing oxidative stress [malondialdehyde (MDA), nitric oxide (NO)], diminishing inflammatory factors [interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) levels], and augmenting the levels of glutathione (GSH) and superoxide dismutase (SOD). The pharmacokinetics study showed that the area under the curve from 0 to 24 hr (AUC 0-24 hr) of 4-ketocyclophosphamide (4-KetoCTX) and carboxyphosphamide (CPM) was significantly increased after GS treatment. This study found that GS treatment can reduce chloroacetaldehyde (CAA) production by affecting CYP3A4, CYP2B6, and CYP2C9 protein expression in the liver. For the metabolomics study, GS attenuated the abnormalities of amino acid metabolic pathways in CP-induced liver injuries of rats and significantly enhanced the l-arginine level while reducing the serum nitric oxide (NO) level. This outcome was confirmed by the inhibition of the activities of NO synthase in the liver of rats.

Modulation of bleomycin-induced oxidative stress and pulmonary fibrosis by N-acetylcysteine in rats via AMPK/SIRT1/NF-κβ

The efficacy of bleomycin (BLM) as an antineoplastic drug is limited to the development of dose and time-dependent pulmonary fibrosis. This study was intended to investigate the effect of N-acetylcysteine (NAC) on BLM-induced pulmonary fibrosis in rats. Twenty rats were randomly divided to the following four groups: Group one served as control; group two received BLM (15 mg/kg, intraperitoneal (ip)) for five consecutive days; group three received NAC (200 mg/kg, ip) for five consecutive days; and group four received NAC 1 hour before BLM for 5 days. The expression of connective tissue growth factor (CTGF), platelet-derived growth factor (PDGF), silent information regulator l (SIRT1), AMP-activated protein kinase (AMPK) were determined by qRT-PCR in lung tissues. The changes in transforming growth factor-beta1 (TGF-β1), tumour necrosis factor-α (TNF-α), interleukin-β1 (IL-β1) and nuclear factor kappa-β (NF-κβ) in serum were measured by ELISA. The tissue antioxidant status was determined biochemically. BLM administration caused pulmonary fibrosis as evidenced by increased levels of inflammatory mediators (TGF-β1, TNF-α, IL-β1 and NF-κβ) in serum (P < .05), elevated lipid peroxidation and nitric oxide and depleted endogenous antioxidants in lung tissue (P < .05). The expression levels of SIRT1 and AMPK were significantly decreased (P < .05), while the expression levels of CTGF and PDGF were increased significantly in the BLM group as compared to the control group (P < .05). These alterations were normalized by NAC intervention. NAC markedly attenuated the lung histopathological changes and reduced collagen deposition. These results suggest that NAC exerted an ameliorative effect against BLM-induced oxidative damage and pulmonary fibrosis via SIRT1/ AMPK/ NF-κβ pathways.

Antioxidant and Anti-Inflammatory Effects of Diallyl Disulfide on Hepatotoxicity Induced by Cyclophosphamide in Rats

Diallyl disulfide (DADS) is a garlic-derived organo-sulfur compound. This study was carried out to investigate the protective potential, antioxidant, and anti-inflammatory effects of this compound against cyclophosphamide (CP)-induced hepatotoxicity in rats. A single intraperitoneal dose of CP (200 mg/kg) resulted in a significant disturbance in hepatic function and oxidative stress, as well as inflammatory biomarkers. In addition, histopathological examination showed distinct changes and increased expression of proliferating cell nuclear antigen in hepatocytes. On the other hand, daily oral preadministration of DADS (200 mg/kg) for 10 days before the CP dose effectively attenuated the hepatotoxicity caused by CP administration as confirmed by significant amelioration of the aforementioned parameters in rat’s liver. It could be concluded that administration of DADS can diminish CP-induced hepatotoxicity through concurrent upregulation of antioxidant and anti-inflammatory responses that denote its possible potential clinical application against side effects of the CP drug.

Protective Effect of Croton macrostachyus (Euphorbiaceae) Stem Bark on Cyclophosphamide-Induced Nephrotoxicity in Rats

Background

Cyclophosphamide is an alkylating antineoplastic agent and its major limitation is injury to normal tissue, leading to multiple organ toxicity, including kidney, heart, liver and reproductive toxicity. Croton macrostachyus (Euphorbiaceae) has been used in Ethiopian traditional medicine to manage renal diseases.

Objective

The present study aims to assess the protective effect of the stem bark extract and solvent fractions of Croton macrostachyus on cyclophosphamide-induced nephrotoxicity in rats.

Methods

Nephrotoxicity was induced using cyclophosphamide 200 mg/kg i.p injection on the first day of the experiment. The negative control groups were administered with cyclophosphamide alone (200 mg/kg, i.p.). The crude extracts were administered at three dose levels (100, 200, and 400 mg/kg), while aqueous and ethyl acetate fractions were given at two dose levels (100 and 200 mg/kg). Excepting the normal control, all groups were subjected to cyclophosphamide toxicity on the first day.

Results

Treatment with crude extract 100 mg/kg and ethyl acetate fraction significantly decreased kidney-to-body weight ratio (P < 0.001). In addition, treatment with Croton macrostachyus crude extract and solvent fractions significantly decreased serum blood urea nitrogen (BUN) level (P < 0.001). Treatment with 100 and 200 mg/kg of ethyl acetate fraction significantly decreased serum creatinine level. Histopathological results confirmed the protective effect of the crude extract and solvent fractions of Croton macrostachyus.

Conclusion

Croton macrostachyus possesses nephroprotective activities and it could be a possible source of treatment for cyclophosphamide-induced nephrotoxicity.

Antioxidant potential of Carica papaya Linn (Caricaceae) leaf extract in mice with cyclophosphamide induced oxidative stress

AIMS: This study aimed to investigate the effects of crude extract of Carica papaya leaves on oxidative stress in mice induced by cyclophosphamide, as well as phytochemical profile characterization of this extract.METHODS: The male Swiss mice received 15 days of treatment with the extract (500 mg kg-1, via gavage) and intraperitoneal injection of cyclophosphamide (75 mg kg-1) or saline (0.9%) on the 15th day. After 24 h the last treatment, the animals were anesthetized for blood withdrawal, sacrificed and removal of the organs for analyses (liver, kidney and heart). In the biochemical tests were determined: hematological parameters in blood, aminotransferases, alkaline phosphatase, glucose and total cholesterol dosages in plasma, enzymatic and non-enzymatic antioxidants and lipid damage marker were evaluated in different tissues, besides genotoxic and histopathological analyzes.RESULTS: In the extract of Carica papaya leaves, the flavonoids quercetin-3β-D-glucoside and rutin were identified, besides present positive results for alkaloids, saponins and tannins. This extract increased the activity of glutathione-S-transferase and catalase enzymes in the liver and reduced the levels of reduced glutathione in the kidneys and hematocrit levels, red cell count, and hemoglobin. It promoted the decrease of the reactive species of thiobarbituric acid (TBARS) in the kidneys and the activity of enzyme aspartate aminotransferase in the plasma and was antimutagenic in the micronucleus test.CONCLUSIONS: The study showed that extract of Carica papaya was beneficial against oxidative events and prevented DNA damage. The extract also showed hepatotoxicity, therefore prolonged infusion of papaya leaves is not advisable.

The Role of Antioxidants in Ameliorating Cyclophosphamide-Induced Cardiotoxicity

The chemotherapeutic and immunosuppressive agent cyclophosphamide has previously been shown to induce complications within the setting of bone marrow transplantation. More recently, cardiotoxicity has been shown to be a dose-limiting factor during cyclophosphamide therapy, and cardiooncology is getting wider attention. Though mechanism of cyclophosphamide-induced cardiotoxicity is not completely understood, it is thought to encompass oxidative and nitrative stress. As such, this review focuses on antioxidants and their role in preventing or ameliorating cyclophosphamide-induced cardiotoxicity. It will give special emphasis to the cardioprotective effects of natural, plant-derived antioxidants that have garnered significant interest in recent times.

Cardioprotective Effect of Croton macrostachyus Stem Bark Extract and Solvent Fractions on Cyclophosphamide-Induced Cardiotoxicity in Rats

Objective

To evaluate the antioxidant and cardioprotective activities of stem bark extract and solvent fractions of Croton macrostachyus on cyclophosphamide-induced cardiotoxicity in rats. Materials and Methods. DPPH free radical scavenging assay method was used to determine antioxidant activity whereas Sprague-Dawley rats were used to evaluate the cardioprotective activity. Except for the normal control, all groups were subjected to cyclophosphamide (200 mg/kg, i.p.) toxicity on the first day. Enalapril at 10 mg/kg was used as a reference. The hydromethanolic crude extract (100, 200, and 400 mg/kg) and aqueous and ethyl acetate fractions (100 and 200 mg/kg, each) were administered for 10 days. The cardioprotective activities were evaluated using cardiac biomarkers such as Troponin I, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total cholesterol (TC), triglyceride (TG), and histopathological studies of heart tissue.

Results

Crude extract and ethyl acetate and aqueous fractions exhibited free radical scavenging activities at IC₅₀ of 594 μg/mL, 419 μg/mL, and 716 μg/mL, respectively. Crude extract at 400 mg/kg decreased the levels of troponin, AST, ALT, and ALP to 0.29 ± 0.06 ng/mL, 103.00 ± 7.63 U/L, 99.80 ± 6.18 U/L, and 108.80 ± 8.81 U/L, respectively. In addition, ethyl acetate fraction at 200 mg/kg decreased the levels of troponin, AST, ALT, and ALP to 0.22 ± 0.02 ng/mL, 137.00 ± 14.30 U/L, 90.33 ± 6.13 U/L, and 166.67 ± 13.50 U/L, respectively, compared with the cyclophosphamide control group.

Conclusions

Croton macrostachyus possesses cardioprotective activities and it could be a possible source of treatment for cardiotoxicity induced by cyclophosphamide.

First phytochemical study and biological activity of the leaves ethanolic extract from Cissus spinosa Cambess

AIMS: The objective of this study was to identify the phytochemical profile and to evaluate the biological effects of the crude ethanolic extract (EE) and the ethanolic fraction (EF) of leaves of the species Cissus spinosa Cambess, after oxidative stress induced by cyclophosphamide (CP) in mice.METHODS: Phytochemical profile was performed detecting functional groups and, analysis of total flavonoids and phenols concentration, as well as the antiradical activity in EE and EF. The phytochemical characterization was done for the identification of flavonoids present in the leaves of the plant. In the biochemical tests, hematological parameters, glucose and total cholesterol dosages in plasma, enzymatic and non-enzymatic antioxidants and lipid damage marker were evaluated in different tissues (liver, kidney and heart), besides genotoxic and immunological analyzes. The animals received 15 days of treatment, via gavage, with EE (50 mg kg-1) or EF (50 mg kg-1) and on the 15th day, an intraperitoneal injection of CP (100 mg kg-1) or saline (0.9%). After 24 h the last treatment, the animals were anesthetized for blood withdrawal, sacrificed and removal of the organs.RESULTS: In the phytochemical analyzes, the presence of alkaloids, flavonoids and phenols was identified, the latter presented a higher concentration for EF. Eight flavonoids were identified - Rutin, Quercetin-3-β-D-glucoside, Quercitrin, Taxifolin, Quercetin, Canferol, Luteolin and Apigenin. In the biochemical analyzes, in general, EE showed a better antioxidant action against oxidative damages, hypoglycemic and antitilipemic action when comparing with EF, probably due to the synergism caused by flavonoids. It was observed the reduction and an increase of micronucleated polychromatic erythrocytes, due to the action of antioxidant compounds and alkaloids present in the plant, also considering the question of the seasonal period that directly interferes in the production of these compounds. In the immunological analysis, the extracts did not stimulate the spontaneous production of oxygen peroxide (H2O2) and nitric oxide (NO•). CONCLUSIONS: Other studies, such as the variation of the chemical composition of the plant by local seasonality, hypoglycemic and antilipemic action, should be carried out to better delineate the biological action present in this plant.

Protective effect of N-acetyl cysteine against radiotherapy-induced cardiac damage

Purpose: Although radiotherapy (RT) is an important component of cancer treatment, it induces adverse tissue reactions in the around of cancer tissue. Therefore, radioprotectives are needed to protect normal tissues. The aim of this study was to investigate the radioprotective effect of N-acetylcysteine (NAC) on RT-induced cardiac damage in rats for the acute term.Materials and methods: The animals were divided into four groups. The rats in control group were injected with saline for 7 d; the rats in NAC group were injected NAC at dose of 240 mg/kg d for 7 d; the rats in RT group were injected with saline for 7 d plus was irradiated 1 h after the last injection and the rats in NAC + RT group were injected with NAC for 7 d and irradiated 1 h after the last NAC dose. The electrocardiogram was recorded and evaluated PR interval, QRS duration, QT interval, T wave alterations and heart rate. Serum interleukin-4, interleukin-6, tumor necrosis factor-alpha, interleukin 1 beta, galectin-3 levels and creatine kinase and creatine kinase isoenzyme-MB activities were determined in all groups. Also, tissue malondialdehyde (MDA) and nitric oxide levels, superoxide dismutase, catalase and glutathione peroxidase activities were determined. In addition, histological changes of heart were evaluated. All measurements were performed 24 h after RT.Results: In the RT group, findings supporting cardiac injury were observed in the electrocardiogram. Also, cytokine levels and oxidative stress were significantly increased. Pretreatment of rats with NAC ameliorated cardiac injury induced by RT.Conclusions: Our findings suggested that NAC may be a potential radioprotector which is capable of preventing cardiac damage.

The molecular mechanisms of lithium-induced cardiotoxicity in male rats and its amelioration by N-acetyl cysteine

Lithium is one of the most powerful and commonly used medications for the treatment of various psychiatric diseases, especially bipolar disorder. However, it has a narrow therapeutic index with toxic effects on various organs. There are several case reports of lithium-induced arrhythmia and ischemia. The current work aimed to study the toxic effects of lithium on the heart of adult albino rats and its molecular mechanisms and the ameliorating effect of N-acetyl cysteine (NAC). Sixty adult male Wistar albino rats were classified into four groups; control, NAC-treated received NAC 500 mg/kg/week dissolved in 1 ml 0.9% sodium chloride intraperitoneal, lithium-treated received 52.5 mg/kg/day of lithium carbonate dissolved in 1 ml 0.9% sodium chloride orally by gavage, and lithium-and-NAC-treated (group IV) received lithium and NAC in the previous doses. After 12 weeks, the rats of group III showed a significant accumulation of ascites and a decrease in the mean arterial blood pressure and electrocardiographic (ECG) findings of ischemia and arrhythmia. In addition, there was an elevation in cardiac biomarkers creatine kinase MB (CK-MB), cardiac troponin I (cTnI), and several histological lesions with a significant increase in the area % of Van Gieson, endothelial nitric oxide synthase (eNOS), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) immunoreaction. There was significant upregulation of microRNA-1, microRNA-21 (miRNA-21), and microRNA-29 (miRNA-29). MiRNA-21 was strongly positively correlated to the area % of 8-OHdG, while miRNA-29 was strongly positively correlated to the area % of Van Gieson staining. NAC significantly improved the cardiotoxic effects of lithium. Being a nontoxic and safe antioxidant, NAC can be used to ameliorate lithium-induced cardiac injury.

Purine versus non-purine xanthine oxidase inhibitors against cyclophosphamide-induced cardiac and bone marrow toxicity in rats

BACKGROUND AND AIM

Cancer is a fatal and serious disease. Cyclophosphamide (CYC) is a commonly used anticancer drug. Cardiotoxicity and myelotoxicity are life-threatening side effects of CYC treatment. We aimed to evaluate the effect of the xanthine oxidase (XO) inhibitors, allopurinol (ALL) and febuxostat (FEB), on CYC-induced cardio- and hematopoietic toxicity in rats.

METHODS

ALL (100 mg/kg/day) or FEB (10 mg/kg/day) were administered orally to rats in the presence and absence of CYC (200 mg/kg kg i.p. single dose) treatment. Serum creatine kinase-MB creatine kinase myocardial band (CK-MB) and lactate dehydrogenase (LDH) activities were estimated. Complete blood counting (CBC), cardiac and bone marrow XO activity, malondialdehyde level, and superoxide dismutase activity were determined. Cardiac and bone marrow histopathological changes were also evaluated.

RESULTS

ALL and FEB significantly decreased CK-MB and LDH induced by CYC. Disturbed levels of XO, oxidative stress parameters, and CBC were also corrected by both XO inhibitors tested, with amelioration of cardiac histopathological changes caused by CYC. Treatment with FEB, but not ALL, prior to CYC challenges normalized bone marrow histopathological changes.

CONCLUSION

These results suggest that both XO inhibitors tested; ALL and FEB can ameliorate CYC-induced cardiotoxicity. However, only FEB can protect against CYC-induced myelotoxicity, whereas ALL, to the contrary, might aggravate it.

The effects of naringin on different cyclophosphamide-induced organ toxicities in rats: investigation of changes in some metabolic enzyme activities

Cyclophosphamide (CYP) is a common anticancer drug used in the treatment of various malignancies. Naringin (NG) is a natural bioflavonoid that have been reported to have many medicinal and pharmacological properties. Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), carbonic anhydrase (CA), α-glycosidase (α-Gly), and aldose reductase (AR) enzymes are the essential biological molecules needed for metabolic processes in all living cells. In the present study, the aim was to investigate the effect of NG against CYP-induced liver, brain, kidney, heart, and testis toxicities on some metabolic enzyme activities such as AChE, BChE, CA, α-Gly, and AR. Thirty-five male Wistar rats were randomly divided into five groups with each group consisting of seven rats. The rats were subjected to oral treatment of NG (50 and 100 mg/kg body weight) for 7 days before administering a single dose of CYP (200 mg/kg body weight, i.p) on the seventh day. Treatment with NG in all tissues regulated these enzyme activities in CYP-induced rats. The results of this study showed that NG regulates abnormal increases and decreases in CYP-induced metabolic enzyme activities in all tissues.

Mitochondrial and lysosomal protective agents ameliorate cytotoxicity and oxidative stress induced by cyclophosphamide and methotrexate in human blood lymphocytes

Cyclophosphamide (CYP) and methotrexate (MTX) have been evaluated for their ability to induce toxicity in human peripheral blood lymphocytes (PBLs) and the protective role of mitochondrial and lysosomal stabilizing agents. The potential toxicity effects of CYP and MTX were measured in vitro by cellular parameters assays such as cellular viability, reactive oxygen species (ROS) formation, mitochondrial membrane permeability transition (mitochondrial membrane potential (MMP)) collapse, lysosomal membrane damage, intracellular reduced glutathione (GSH), extracellular oxidized glutathione (GSSG), and lipid peroxidation. Separately, human lymphocytes were treated with concentrations of 0.1, 0.2, 0.4, 0.8, and 1.6 ng/mL for CYP and 1, 2, 5, and 10 µg/mL for MTX for 6 h. Statistical evaluations showed that CYP and MTX significantly decreased the cell viability at the three highest concentrations when compared with both the negative and solvent controls. In addition, CYP and MTX were significantly induced ROS formation, MMP collapse, lysosomal membrane damage, lipid peroxidation, and GSH depletion compared with the controls. Mitochondrial and lysosomal protective agents like cyclosporine A and chloroquine, respectively, decreased cytotoxicity and oxidative stress induced by CYP and MTX. The present results indicate that CYP and MTX are toxic to human PBLs and their toxicity could be ameliorated by mitochondrial and lysosomal protective agents.

Therapy of the rat hemorrhagic cystitis induced by cyclophosphamide. Stable gastric pentadecapeptide BPC 157, L-arginine, L-NAME

We focused on the cyclophosphamide-induced hemorrhagic cystitis (100 mg/kg/day intraperitoneally throughout three days) as a particular NO-system disturbance, and therapy possibilities. We demonstrated that it may be attenuated by subsequent administration of the NOS substrate L-arginine (100 mg/kg/day intraperitoneally), aggravated by NOS-blocker L-NAME (5 mg/kg/day intraperitoneally), all influenced by the stable gastric pentadecapeptide BPC 157 (10 μg/kg/day, 10 ng/kg/day, intraperitoneally or perorally, in drinking water). Regularly, cyclophosphamide dose- and time-dependently induced severe hemorrhagic cystitis lesions, gross lesions, and corresponding urothelial necrosis, vesical edema, erosion, hemorrhage, inflammation, and ulceration, microscopically. The bladder wet weight dramatically increased. Functionally, already after first cyclophosphamide administration, there is an increased leak point pressure. Until the second cyclophosphamide administration, L-arginine consistently attenuated regular cyclophosphamide-induced severe hemorrhagic cystitis lesions, grossly and microscopically, but not functionally. L-NAME aggravated these lesions and eradicated beneficial effect of L-arginine when combined. BPC 157 administration after cyclophosphamide, given in either dose or in either regimen markedly attenuated all cyclophosphamide lesions, grossly, microscopically. The increase of the bladder wet weight was consistently attenuated. Functionally, increased leak point pressure was reversed to the values noted in normal rats. The similar findings were noted in rats that received BPC 157 together with L-NAME or L-arginine, given alone or combined. Thus, the lesions are NO-related based on the administration of L-NAME as well as administration of L-arginine, and their mutual interaction, and counteraction by BPC 157 application. Likewise, we reveal new therapeutic possibilities, emphasizing stable gastric pentadecapeptide BPC 157 and L-arginine, versus L-NAME in rats underwent cyclophosphamide-induced cystitis.

Nitrogen Mustards as Anticancer Chemotherapies: Historic Perspective, Current Developments and Future Trends

Nitrogen mustards, a family of DNA alkylating agents, marked the start of cancer pharmacotherapy. While traditionally characterized by their dose-limiting toxic effects, nitrogen mustards have been the subject of intense research efforts, which have led to safer and more effective agents. Even though the alkylating prodrug mustards were first developed decades ago, active research on ways to improve their selectivity and cytotoxic efficacy is a currently active topic of research. This review addresses the historical development of the nitrogen mustards, outlining their mechanism of action, and discussing the improvements on their therapeutic profile made through rational structure modifications. A special emphasis is made on discussing the nitrogen mustard prodrug category, with Cyclophosphamide (CPA) serving as the main highlight. Selected insights on the latest developments on nitrogen mustards are then provided, limiting such information to agents that preserve the original nitrogen mustard mechanism as their primary mode of action. Additionally, future trends that might follow in the quest to optimize these invaluable chemotherapeutic medications are succinctly suggested.

Molecular mechanism involved in cyclophosphamide-induced cardiotoxicity: Old drug with a new vision

Cyclophosphamide (CP) is an important anticancer drug which belongs to the class of alkylating agent. Cyclophosphamide is mostly used in bone marrow transplantation, rheumatoid arthritis, lupus erythematosus, multiple sclerosis, neuroblastoma and other types of cancer. Dose-related cardiotoxicity is a limiting factor for its use. CP-induced cardiotoxicity ranges from 7 to 28% and mortality ranges from 11 to 43% at the therapeutic dose of 170-180 mg/kg, i.v. CP undergoes hepatic metabolism that results in the production of aldophosphamide. Aldophosphamide decomposes into phosphoramide mustard & acrolein. Phosphoramide is an active neoplastic agent, and acrolein is a toxic metabolite which acts on the myocardium and endothelial cells. This is the first review article that talks about cyclophosphamide-induced cardiotoxicity and the different signaling pathways involved in its pathogenicity. Based on the available literature, CP is accountable for cardiomyocytes energy pool alteration by affecting the heart fatty acid binding proteins (H-FABP). CP has been found associated with cardiomyocytes apoptosis, inflammation, endothelial dysfunction, calcium dysregulation, endoplasmic reticulum damage, and mitochondrial damage. Molecular mechanism of cardiotoxicity has been discussed in detail through crosstalk of Nrf2/ARE, Akt/GSK-3β/NFAT/calcineurin, p53/p38MAPK, NF-kB/TLR-4, and Phospholamban/SERCA-2a signaling pathway. Based on the available literature we support the fact that metabolites of CP are responsible for cardiotoxicity due to depletion of antioxidants/ATP level, altered contractility, damaged endothelium and enhanced pro-inflammatory/pro-apoptotic activities resulting into cardiomyopathy, myocardial infarction, and heart failure. Dose adjustment, elimination/excretion of acrolein and maintenance of endogenous antioxidant pool could be the therapeutic approach to mitigate the toxicities.

Effects of treatment with chemotherapy and/or tamoxifen on the biomarkers of cardiac injury and oxidative stress in women with breast cancer

There has been an increase in deaths from cardiovascular diseases following breast cancer therapy. Evidence has shown that this outcome is, in part, associated with cardiotoxicity induced by the chemotherapeutic drugs and the increase in oxidative stress. The aim of this study was to evaluate the effects of chemotherapy and hormone therapy with tamoxifen on the biomarkers of cardiac injury and oxidative stress in women with breast cancer.Thirty women were followed-up for 1 year and were divided into 3 groups according to the treatment protocol: women treated only with tamoxifen and clinical follow up for 12 months (Tam, n = 10); women treated only with chemotherapy for 6 months with clinical follow up for an additional 6-month period (Chemo, n = 10); and women who received chemotherapy for 6 months followed by a 6-month period only with tamoxifen therapy and clinical follow up (Chemo + Tam, n = 10). Analysis of the blood levels of cardiac troponin I (cTnI), advanced oxidation protein products (AOPP) and the activity of the plasmatic isoform of the antioxidant enzyme glutathione peroxidase (GPx) was performed before treatment (T0) and at 6 (T6) and 12 (T12) months after treatment.The Chemo group showed higher levels of cTnI (0.065 ± 0.006 ng/mL, P < .05) and AOPP (4.99 ± 0.84 μmol/L, P < .05) and reduced GPx activity (24.4 ± 1.1 nM/min/mL, P < .05) at T12 than the Tam group (cTnI: 0.031 ± 0.001 ng/mL; AOPP: 1.40 ± 0.10 μmol/L; GPx: 28.0 ± 0.7 nM/min/mL) and Chemo + Tam group (cTnI: 0.037 ± 0.002 ng/mL; AOPP: 2.53 ± 0.30 μmol/L; GPx: 29.5 ± 1.0 nM/min/mL).These data support the hypothesis that long-term oxidative stress after chemotherapy may have an impact on cardiovascular diseases and that tamoxifen has cardioprotective effects.

Role of metabolites of cyclophosphamide in cardiotoxicity

Background

The dose-limiting toxic effect of cyclophosphamide (CY) is cardiotoxicity. The pathogenesis of myocardial damage is poorly understood, and there is no established means of prevention. In previous studies, we suggested that for CY-induced cardiotoxicity, whereas acrolein is the key toxic metabolite, carboxyethylphosphoramide mustard (CEPM) is protective. We sought to verify that acrolein is the main cause of cardiotoxicity and to investigate whether aldehyde dehydrogenase (ALDH), which is associated with greater CEPM production, is involved in the protective effect for cardiotoxicity. We also evaluated the protective effect of N-acetylcysteine (NAC), an amino acid with antioxidant activity and a known acrolein scavenger.

Methods

H9c2 cells were exposed to CY metabolites HCY (4-hydroxy-cyclophosphamide), acrolein or CEPM. The degree of cytotoxicity was evaluated by MTT assay, lactate dehydrogenase (LDH) release, and the production of reactive oxygen species (ROS). We also investigated how the myocardial cellular protective effects of CY metabolites were modified by NAC. To quantify acrolein levels, we measured the culture supernatants using high performance liquid chromatography. We measured ALDH activity after exposure to HCY or acrolein and the same with pre-treatment with NAC.

Results

Exposure of H9c2 cells to CEPM did not cause cytotoxicity. Increased ROS levels and myocardial cytotoxicity, however, were induced by HCY and acrolein. In cell cultures, HCY was metabolized to acrolein. Less ALDH activity was observed after exposure to HCY or acrolein. Treatment with NAC reduced acrolein concentrations.

Conclusions

Increased ROS generation and decreased ALDH activity confirmed that CY metabolites HCY and acrolein are strongly implicated in cardiotoxicity. By inhibiting ROS generation, increasing ALDH activity and decreasing the presence of acrolein, NAC has the potential to prevent CY-induced cardiotoxicity.

Inhibition of NF-κB/TNF-α pathway may be involved in the protective effect of resveratrol against cyclophosphamide-induced multi-organ toxicity

CONTEXT

Cyclophosphamide (CyP), an efficient anticancer drug, may damage normal human cells. Resveratrol (RES), a natural polyphenol, has a diverse pharmacological properties.

OBJECTIVE

To test possible protective effect of RES on multi-organ damage caused by CyP.

MATERIALS AND METHODS

RES (10 mg/kg/day) was administered orally for 8 days. In independent rat groups, CyP toxicity was induced via a single dose of 150 mg/kg i.p. 3 days before the end of experiment, with or without RES treatment.

RESULTS

Compared to control, CyP caused significant increase in organ-to-body weight ratios of heart, kidney and liver, with deterioration in their functional parameters; namely serum creatine kinase, blood urea nitrogen, creatinine, alanine aminotransferase and aspartate aminotransferase. CyP also caused distortion in these organs' histology, with significant tissue oxidative stress, manifested by decrease in reduced glutathione and catalase, as well as increase in malondialdehyde and nitric oxide levels. Furthermore, CyP caused multi-organ inflammatory effects as shown by increased tumor necrosis factor-α levels, as well as up-regulation of nuclear factor-κB expressions. Using RES concurrently with CyP restored heart, kidney and liver functional parameters, as well as their normal histology. RES also reversed oxidative stress, as well as inflammatory signs caused by CyP alone.

CONCLUSIONS

RES may be beneficial adjuvant that confers multi-organ protection against CyP toxicity via antioxidant and anti-inflammatory mechanisms.

Cyclophosphamide induced stomach and duodenal lesions as a NO-system disturbance in rats: L-NAME, L-arginine, stable gastric pentadecapeptide BPC 157

We revealed a new point with cyclophosphamide (150 mg/kg/day intraperitoneally for 7 days): we counteracted both rat stomach and duodenal ulcers and increased NO- and MDA-levels in these tissues. As a NO-system effect, BPC 157 therapy (10 µg/kg, 10 ng/kg, intraperitoneally once a day or in drinking water, till the sacrifice) attenuated the increased NO- and MDA-levels and nullified, in rats, severe cyclophosphamide-ulcers and even stronger stomach and duodenal lesions after cyclophosphamide + L-NAME (5 mg/kg intraperitoneally once a day). L-arginine (100 mg/kg intraperitoneally once a day not effective alone) led L-NAME-values only to the control values (cyclophosphamide + L-NAME + L-arginine-rats). Briefly, rats were sacrificed at 24 h after last administration on days 1, 2, 3, or 7, and assessment included sum of longest lesions diameters (mm) in the stomach and duodenum, oxidative stress by quantifying thiobarbituric acid reactivity as malondialdehyde equivalents (MDA), NO in stomach and duodenal tissue samples using the Griess reaction. All these parameters were highly exaggerated in rats who underwent cyclophosphamide treatment. We identified high MDA-tissue values, high NO-tissue values, ulcerogenic and beneficial potential in cyclophosphamide-L-NAME-L-arginine-BPC 157 relationships. This suggests that in cyclophosphamide damaged rats, NO excessive release generated by the inducible isozyme, damages the vascular wall and other tissue cells, especially in combination with reactive oxygen intermediates, while failing endothelial production and resulting in further aggravation by L-NAME which was inhibited by L-arginine. Finally, BPC 157, due to its special relations with NO-system, may both lessen increased MDA- and NO-tissues values and counteract effects of both cyclophosphamide and L-NAME on stomach and duodenal lesions.

Enolate-Forming Phloretin Pharmacophores: Hepatoprotection in an Experimental Model of Drug-Induced Toxicity

Drug-induced toxicity is often mediated by electrophilic metabolites, such as bioactivation of acetaminophen (APAP) to N-acetyl-p-benzoquinone imine (NAPQI). We have shown that APAP hepatotoxicity can be prevented by 2-acetylcyclopentanone (2-ACP). This 1,3-dicarbonyl compound ionizes to form an enolate nucleophile that scavenges NAPQI and other electrophilic intermediates. In this study, we expanded our investigation of enolate-forming compounds to include analyses of the phloretin pharmacophores, 2',4',6'-trihydroxyacetophenone (THA) and phloroglucinol (PG). Studies in a mouse model of APAP overdose showed that THA provided hepatoprotection when given either by intraperitoneal injection or oral administration, whereas PG was hepatoprotective only when given intraperitoneally. Corroborative research characterized the molecular pharmacology (efficacy, potency) of 2-ACP, THA, and PG in APAP-exposed isolated mouse hepatocytes. For comparative purposes, N-acetylcysteine (NAC) cytoprotection was also evaluated. Measurements of multiple cell parameters (e.g., cell viability, mitochondrial membrane depolarization) indicated that THA and, to a lesser extent, PG provided concentration-dependent protection against APAP toxicity, which exceeded that of 2-ACP or NAC. The enolate-forming compounds and NAC truncated ongoing APAP exposure and thereby returned intoxicated hepatocytes toward normal viability. The superior ability of THA to protect is related to multifaceted modes of action that include metal ion chelation, free radical trapping, and scavenging of NAPQI and other soft electrophiles involved in oxidative stress. The rank order of potency for the tested cytoprotectants was consistent with that determined in a parallel mouse model. These data suggest that THA or a derivative might be useful in treating drug-induced toxicities and other conditions that involve electrophile-mediated pathogenesis.

Prevention of cyclophosphamide-induced hepatotoxicity and genotoxicity: Effect of an L-cysteine based oxovanadium(IV) complex on oxidative stress and DNA damage

Vanadium has been emerged as a promising agent owing to its ability to prevent several types of cancer. This study was aimed to investigate the protective role of an organovanadium complex, viz., oxovanadium(IV)-L-cysteine methyl ester (VC-IV) against cyclophosphamide (CP)-induced hepatotoxicity and genotoxicity in mice. Oral administration of VC-IV quite effectively ameliorated CP-induced histopathological lesions and reduced levels of alanine transaminase, aspartate transaminase and alkaline phosphatase. In addition, VC-IV significantly attenuated CP-induced oxidative stress in the liver as evident from levels of reactive oxygen species, nitric oxide and lipid peroxidation. Restoration of glutathione level and activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase) were also observed upon VC-IV administration. Moreover, VC-IV significantly mitigated CP-induced chromosomal aberrations, micronuclei formation, DNA fragmentation and apoptosis in bone marrow cells and DNA damage in lymphocytes. The present study showed that VC-IV could provide adequate protection against CP-induced hepatotoxicity and genotoxicity in vivo.