Chemoprotective effects of captopril against cyclophosphamide-induced genotoxicity in mouse bone marrow cells

Amelioration of cyclophosphamide-induced DNA damage, oxidative stress, and hepato- and neurotoxicity by Piper longum extract in rats: The role of γH2AX and 8-OHdG

Background: The identification of genoprotectants is a promising strategy for improving human health. Piper longum has drawn scientific attention because of its diverse biological effects and traditional utilization. The current investigation aims to evaluate the genome-stabilizing potential of Piper longum against cyclophosphamide-associated genotoxicity.

Methods: We adopted a funnel screening with a three-tier evaluation approach, where Piper longum was investigated in an acellular medium, peripheral blood lymphocytes, and a rodent model. The genoprotective action of the Piper longum extract was initially performed with plasmid pBluescript SK(-) DNA. Furthermore, the extract and various fractions were screened against cyclophosphamide-induced genotoxicity using a cytokinesis-block micronucleus assay and a chromosomal aberration assay in human peripheral blood lymphocytes. The genome-stabilizing action of the extract and potent (hexane) fraction was further confirmed in vivo in Wistar albino rats by evaluating them using mammalian erythrocyte micronucleus tests, DNA fragmentation, oxidative stress markers, 8-hydroxy-2-deoxyguanosine (8-OHdG), γH2AX, and histopathological lesions in the liver and hippocampus. Additionally, acute and sub-acute toxicity studies were conducted following the Organization for Economic Co-operation and Development (OECD) guidelines for rats. Furthermore, the extract was quantified and characterized by high-performance thin-layer chromatography (HPTLC), ultra-high performance liquid chromatography–mass spectroscopy (UPLC-MS), and gas chromatography–mass spectrometry (GC-MS).

Results: The Piper longum ethanol extract was shown to protect plasmid pBluescript SK(-) DNA against H2O2-induced strand breaks. In human lymphocytes, the extract and hexane fraction showed a reduction in micronucleus formation (p < 0.001) and chromosomal aberrations (p < 0.01) against cyclophosphamide. Furthermore, the extract and fraction treatment, when administered at 200 mg/kg for 28 days in Wistar rats, restored cyclophosphamide-induced genomic instability by reducing micronucleus formation and DNA fragmentation; restoring redox homeostasis; decreasing 8-OHdG, a hallmark of oxidative DNA damage; reducing γH2AX, a DNA double-strand break (DSB) marker; and preserving the liver and hippocampus against histopathological lesions. The extract and fraction revealed no signs of systemic toxicity at the used doses. Piperine and piperlongumine are the major alkaloids quantified along with the presence of flavonoids in the ethanol extract and the presence of fatty acids and terpenoids in the hexane fraction of Piper longum.

Conclusion: Our investigation confirms the genoprotective action of Piper longum by reducing cyclophosphamide-associated cytogenotoxicity, oxidative stress, hepato- and neurotoxicity, oxidative DNA damage, and DNA double-strand breaks. The outcomes are critical for mitigating the genotoxic effects of chemotherapy recipients, requiring further attention.

Captopril downregulates expression of Bax/cytochrome C/caspase-3 apoptotic pathway, reduces inflammation, and oxidative stress in cisplatin-induced acute hepatic injury

Cisplatin (Cis) is an effective cancer therapy commonly employed in many therapeutic regimens. However, treatment regimens that contain either a high dose or cumulative doses of Cis could trigger liver damage. A unique study demonstrated that captopril (Cap) protects against Cis-induced liver toxicity, but only some liver function enzymes and some antioxidant enzymes were investigated in that study. Our study aims to elucidate the protective mechanism of Cap against Cis liver toxicity. Acute liver toxicity was induced in rats by injecting a single Cis dose (7.5 mg/kg) in three groups (n = 6). Two groups were pre-treated with low (50 mg/kg) and high (100 mg/kg) Cap doses for one week before Cis injection, and the third group was injected with Cis only. The high Cap dose significantly improved liver function markers (ALT, AST, and ALP) and hepatic tissue pathology. The low Cap dose significantly improved ALP and, to a lesser extent, hepatic tissue pathology. Both Cap doses significantly decreased liver contents of MDA, IL-1β, and cleaved caspase-3; and liver protein expression of TNF-α, Bax, and caspase-3. The high Cap dose significantly increased liver contents of GSH, GPx, CAT, and SOD, and the liver protein expression of Bcl2. Moreover, only the high Cap dose significantly decreased liver IL-6 content and cytochrome C protein expression. Cap did not inhibit the antitumor impact of Cis against HCT116 cancer cells. Therefore, Cap restricts Cis-induced liver toxicity by reducing inflammation and apoptosis and augmenting the antioxidant system.

Genotoxic and mutagenic studies of teratogens in developing rat and mouse

In this review, genotoxic and mutagenic effects of teratogenic chemical agents in both rat and mouse have been reviewed. Of these chemicals, 97 are drugs and 33 are pesticides or belong to other groups. Large literature searches were conducted to determine the effects of chemicals on chromosome abnormalities, sister chromatid exchanges, and micronucleus formation in experimental animals such as rats and mice. In addition, studies that include unscheduled DNA synthesis, DNA adduct formations, and gene mutations, which help to determine the genotoxicity or mutagenicity of chemicals, have been reviewed. It has been estimated that 46.87% of teratogenic drugs and 48.48% of teratogenic pesticides are positive in all tests. So, all of the teratogens involved in this group have genotoxic and mutagenic effects. On the other hand, 36.45% of the drugs and 21.21% of the pesticides have been found to give negative results in at least one test, with the majority of the tests giving positive results. However, only 4.16% of the drugs and 18.18% of the pesticides were determined to give negative results in the majority of the tests. Among tests with major negative results, 12.50% of the teratogenic drugs and 12.12% of the teratogenic pesticides were negative in all conducted tests.

Protective effect of captopril against diazinon induced nephrotoxicity and neurotoxicity via inhibition of ROS-NO pathway

Diazinon (Dz) is a widely used insecticide. It can induce nephrotoxicity and neurotoxicity via oxidative stress. Captopril, an angiotensin-converting enzyme inhibitor, is known for its antioxidant properties. In this study, we used captopril for ameliorating of Dz-induced kidney and brain toxicity in rats. Animals were divided into five groups as follows: negative control (olive oil), Dz (150 mg kg^-1), captopril (60 and 100 mg kg^-1) and positive control (N-acetylcysteine 200 mg kg^-1) were injected intraperitoneally 30 min before Dz. After 24 h, animals were anesthetized and the brain and kidney tissues were separated. Then oxidative stress factors were evaluated. Also, blood was collected for assessment of blood urea nitrogen (BUN), creatinine (Cr) and nitric oxide (NO) levels. Dz significantly increased oxidative stress markers such as reactive oxygen species (ROS), lipid peroxidation, and protein carbonyl as well as glutathione (GSH) oxidation in both tissues. Increased levels of the BUN, Cr and NO were observed after Dz injection. Interestingly, captopril administration significantly decreased ROS production in both tissues. Captopril significantly protected kidney and brain against lipid peroxidation and GSH oxidation. Administration of captopril could markedly inhibit protein carbonyl production in kidney and brain after Dz injection. Furthermore, captopril ameliorated the increased level of BUN, Cr and NO. These results suggested that captopril can prevent Dz-induced oxidative stress, nephrotoxicity and neurotoxicity because of its antioxidant activity.

Antigenotoxic effects of a polyherbal drug septilin against the genotoxicity of cyclophosphamide in mice

Septilin (Spt) is a polyherbal drug formulation from Himalaya Drug Company, consisting of extracts from different medicinal plants and minerals. In the traditional system of medicine, septilin is being used as immunomodulatory, antioxidant and anti-inflammatory agent. In the present study, the protective effects of septilin against the genotoxicity of cyclophosphamide (CP) a widely used alkylating anticancer drug was evaluated by using in vivo micronucleus (MN) and sperm shape abnormality assays in Swiss albino mice. CP administered intraperitoneally at a dose of 50 mg/kg b.w. was used as positive mutagen. Different doses of septilin viz., 125, 250 and 500 mg/kg b.w. was orally administered for 5 consecutive days. CP was administered intraperitoneally on 5th day. MN and sperm preparations were made after 24 h and 35 days respectively. CP induced significant MN in both bone marrow and peripheral blood cells and also a high frequency of abnormal sperms. In septilin supplemented animals, no significant induction of MN and abnormal sperms was recorded. In septilin supplemented groups, a dose dependent significant decrease in CP induced clastogenicity was observed. Thus the current in vivo study revealed the antigenotoxic effects of septilin against CP induced damage, in both somatic and germ cells of Swiss albino mice.

Methanolic Extract of Curcuma caesia Roxb. Prevents the Toxicity Caused by Cyclophosphamide to Bone Marrow Cells, Liver and Kidney of Mice

INTRODUCTION

With an ever increasing cause of cancer, it has been recommended to treat with conventional drugs, however because of the side effects caused by the conventional drugs, the research on medicinal plants has been intensified due to their less adverse and toxic effects.

OBJECTIVES

The primary objective of the present study was to evaluate the protective effect of the medicinal plant Curcuma caesia Roxb. against free radicals ABTS(+) and O2 (-). Also it was aimed to evaluate the protective effect of C.caesia Roxb. against the chemotherapeutic drug Cyclophosphamide and its side effects in liver and kidney.

METHODS

The rhizomes of the plant was extracted with methanol through soxhlet and its antioxidant activity was tested against ABTS(+) and O2 (-). For antigenotoxic studies, animals were divided into eight groups and micronucleus assay was employed and for biochemical analysis serum sample was collected from the blood and SGOT, SGPT analysis was performed. Also the biochemical analysis was performed from both the liver and kidney.

RESULTS

The methanolic extract of Curcuma caesia Roxb. was found to scavenge the free radicals ABTS(+) and O2 (-). the micronuclei formation was found to be increased in the positive control group as compared to the negative control group significantly (P<0.002) however increase in the number of micronuclei was found to be decrease with the pretreatment of the extract at different concentrations significantly as compared to the negative control groups (P<0.01, P<0.005, P<0.001). The increased level of serum SGPT and SGOT as well as peroxidation level in both liver and kidney due to treatment of cyclophosphamide was also found to be decreased with the pretreatment of the extract significantly as compared to the positive control groups. There was decreased in the level of endogenous antioxidant such as GSH and GR in the positive control group however decreased level of GSH and GR was found to be increased with the pretreatment of the methanolic extract of C. caesia Roxb.

CONCLUSION

The present study suggested that the methanolic extract of C. caesia Roxb has not shown any genotoxicity and reduces the genotoxicity caused by cyclophosphamide. It was also to have the protective effects against the liver and kidney. So it could be provided as one of the herbal supplementation in chemoprevention of CP to ameliorate the side effects of it.

SUMMARY

Cancer is characterized by uncontrolled growth of cells and much research has been done for the past several years from various disciplines for the treatment of cancer but till now no therapy has been discovered. Treatment of cancer with chemotherapeutic drugs has been suggested to prevent cancer cells however they are often limited with their toxicity to normal cells. Therefore it has been suggested that the supplementation of medicinal plants which are rich source of antioxidants can decrease the toxic effect caused by chemotherapeutic drugs. Curcuma caesia Roxb is a medicinal plant which has high antioxidant activity, as per present study, methanolic extract of Curcuma caesia Roxb prevents the toxicity caused by cyclophosphosphamide (chemotherapeutic drug) in bone marrow cells by reducing the micronuclei formation; it also prevents the hepatotoxicity and nephrotoxicity caused by cyclophosphamide, so it can be used as a supplement in cancer treatment with cyclophosphamide.

Effect of Butea monosperma leaf extracts on cyclophosphamide induced clastogenicity and oxidative stress in mice

Background:

Butea monosperma is a medium sized deciduous tree of family Fabaceae. It is widely used by rural people in India to cure many disorders. It possesses antioxidant and anticancer activity which is a prerequisite for anticlastogenic activity.

Objective:

To evaluate the effect of Butea monosperma leaf extracts on cyclophosphamide induced clastogenicity and oxidative stress in mice.

Materials and Methods:

The present study assessed the role of aqueous and ethanolic leaf extracts of B. monosperma (AQEBM and ETEBM) on cyclophosphamide (CP) induced oxidative stress and DNA damage in mice using micronucleus assay for anticlastogenic activity and biochemical estimation of malondialdehyde (MDA) and glutathione (GSH) for antioxidant activity. The frequency of the micronucleated erythrocytes and mitotic index was studied in peripheral blood and bone marrow after 24 and 48 h of clastogenic exposure.

Results:

CP treatment led to a significant (P < 0.001) increase in the frequency of micronuclei and decrease in the mitotic index (MI) in bone marrow and peripheral blood cells. Moreover, CP also significantly increased the lipid peroxidation as evidenced by an increase in the MDA content and decreased the antioxidant enzyme (GSH) in mice liver. Pretreatment with AQEBM and ETEBM reduced the frequency of micronuclei and increased the MI in the bone marrow and peripheral blood cells and also restored the MDA and GSH levels in mice liver.

Conclusion:

The AQEBM and ETEBM do contain compounds capable of inhibiting the CP induced oxidative stress and subsequent DNA damage in both the peripheral blood and bone marrow cells in mice.

The protective effect of Canova homeopathic medicine in cyclophosphamide-treated non-human primates

BACKGROUND

Canova activates macrophages and indirectly induces lymphocyte proliferation. Here we evaluated the effects of Canova in cyclophosphamide-treated non-human primates.

METHODS

Twelve Cebus apella were evaluated. Four animals were treated with Canova only. Eight animals were treated with two doses of cyclophosphamide (50 mg/kg) and four of these animals received Canova. Body weight, biochemistry and hematologic analyses were performed for 40 days. Micronucleus and comet assays were performed for the evaluation of DNA damage.

RESULTS

We observed that cyclophosphamide induced abnormal WBC count in all animals. However, the group treated with cyclophosphamide plus Canova presented a higher leukocyte count than that which received only cyclophosphamide. Cyclophosphamide induced micronucleus and DNA damage in all animals. The frequency of these alterations was significantly lower in the Canova group than in the group without this medicine.

CONCLUSIONS

Our results demonstrated that Canova treatment minimizes cyclophosphamide myelotoxicity in C. apella.

Assessment of oxidative stress and chromosomal aberration inducing potential of three medical grade silicone polymer materials

Medical expenditures for devices are increasing along with the ageing of human population and the synthesis of materials such as silicone polymers is on upsurge for manufacturing these devices. The International Organization for Standardization (ISO) emphasizes a battery of tests for preclinical assessment of biocompatibility of medical devices. Genotoxicity assays have become an integral component of these test procedures and it employs a set of in vitro and in vivo experiments to detect mutagens. Hence, this study was performed with an intention to investigate the genotoxic potential of the physiological saline extracts of three medical grade silicone polymer materials by the in vitro chromosomal aberration assay using human peripheral blood lymphocytes. Further, the oxidative stress inducing potential of the material extracts was investigated in vivo in mice liver homogenates using cyclophosphamide as positive control. The investigation revealed that none of the three materials were able to produce marked human lymphocyte chromosomal aberration, suggesting the absence of mutagens. The materials also showed negative results in their oxidative stress inducing potential, which was revealed by the normal levels of lipid peroxidation and unaltered levels of glutathione and its metabolizing enzymes in the mice liver tissue homogenates. It was interesting to observe a significant correlation between the genotoxic and antioxidant parameters investigated. Hence, it is suggested that the estimation of antioxidant status would serve as a better preliminary testing procedure prior to evaluating the genetic and molecular toxicity mechanisms of medical devices and/or materials intended for manufacture of such devices.

Tinospora cordifolia ameliorates urotoxic effect of cyclophosphamide by modulating GSH and cytokine levels

Cyclophosphamide (CP) is a commonly used anti-cancer drug which causes toxicity by its reactive metabolites. In this study we investigated the effect of Tinospora cordifolia on urotoxicity induced by acute dose of CP using Swiss albino mice model. Administration of an alcoholic extract of the plant T. cordifolia (Family: Menispermaceae) (200 mg/kg i.p.) for 5 days reduced CP (1.5 mmol/kg body wt. i.p.) induced urotoxicity as evident from the morphological analysis of bladder, decreased the relative bladder and liver weights and also decreased level of urea nitrogen and protein in blood as well as urine. Severely inflamed and dark coloured urinary bladders of the CP alone treated animals were found to be normalized by the treatment of T. cordifolia. GSH content, which was drastically reduced by CP administration in both bladder and liver was enhanced by treatment with T. cordifolia. Histopathological analysis of the bladder of CP alone-treated group showed severe necrotic damage where as the T. cordifolia-treated group showed normal bladder architecture. The lowered levels of cytokines IFN-γ, IL-2, after CP treatment were found to be increased in treated animals. At the same time the level of pro-inflammatory cytokine TNF-α, which was elevated during CP administration, was significantly reduced by extract administration. This study clearly demonstrates uroprotective role of T. cordifolia from CP induced toxicities by modulating GSH and pro-inflammatory cytokine levels.

Possible involvement of oxidative stress in 5-fluorouracil-mediated myelosuppression in mice

Certain chemotherapeutic agents subject cells to oxidative stress, thereby promoting adverse effects. However, the molecular machinery governing 5-fluorouracil (5-FU)-mediated myelotoxicity is obscure. The purpose of this study was to clarify whether 5-FU-induced myelotoxicity is a cause of oxidative stress. Treatment of mice with 5-FU (75 mg/kg, i.p.) caused a significant induction of haem oxygenase-1 and a decrease in glutathione contents in bone marrow cells, both of which are the indicators of oxidative stress. The 5-FU-mediated decrease in the myeloid colony formation was intensified in Nrf2(-/-) mice, in which antioxidant proteins were down-regulated. N-Acetylcysteine reversed the 5-FU-induced decreases in the glutathione content, number of bone marrow cells per femur and myeloid colony formation. Results from the present study reveal that 5-FU induces oxidative stress in bone marrow, which is involved, at least in part, in myelotoxicity in mice. Therefore, Nrf2-dependent genes as well as glutathione levels in bone marrow could be therapeutic targets for decreasing such side-effects in 5-FU-based chemotherapy.

Cyclophosphamide enhances human tumor growth in nude rat xenografted tumor models

The effect of the immunomodulatory chemotherapeutic agent cyclophosphamide (CTX) on tumor growth was investigated in primary and metastatic intracerebral and subcutaneous rat xenograft models. Nude rats were treated with CTX (100 mg/kg, intraperitoneally) 24 hours before human ovarian carcinoma (SKOV3), small cell lung carcinoma (LX-1 SCLC), and glioma (UW28, U87MG, and U251) tumor cells were inoculated subcutaneously, intraperitoneally, or in the right cerebral hemisphere or were infused into the right internal carotid artery. Tumor development was monitored and recorded. Potential mechanisms were further investigated. Only animals that received both CTX and Matrigel showed consistent growth of subcutaneous tumors. Cyclophosphamide pretreatment increased the percentage (83.3% vs 0%) of animals showing intraperitoneal tumors. In intracerebral implantation tumor models, CTX pretreatment increased the tumor volume and the percentage of animals showing tumors. Cyclophosphamide increased lung carcinoma bone and facial metastases after intra-arterial injection, and 20% of animals showed brain metastases. Cyclophosphamide transiently decreased nude rat white blood cell counts and glutathione concentration, whereas serum vascular endothelial growth factor was significantly elevated. Cyclophosphamide also increased CD31 reactivity, a marker of vascular endothelium, and macrophage (CD68-positive) infiltration into glioma cell-inoculated rat brains. Cyclophosphamide may enhance primary and metastatic tumor growth through multiple mechanisms, including immune modulation, decreased response to oxidative stress, increased tumor vascularization, and increased macrophage infiltration. These findings may be clinically relevant because chemotherapy may predispose human cancer subjects to tumor growth in the brain or other tissues.

Neutrophil depletion causes a fatal defect in murine pulmonary Staphylococcus aureus clearance

BACKGROUND

Staphylococcus aureus is the most common cause of healthcare-associated pneumonia. Despite the significant morbidity and mortality associated with the disease, animal models of S. aureus pneumonia are rare.

MATERIALS AND METHODS

We examined the pathogenicity of four different strains of S. aureus (both methicillin-sensitive and -resistant as well as Panton-Valentine leukocidin-positive and -negative) in four strains of immunocompetent inbred and outbred mice (FVB/N, C57Bl/6, BALB/c, ND4; n = 148). The immunological basis for the development of murine S. aureus pneumonia was then determined by selectively depleting neutrophils, lymphocytes, or pulmonary macrophages prior to the onset of infection. An additional cohort of animals was rendered immunosuppressed by induction of abdominal sepsis via cecal ligation and puncture 2, 4, or 7 d prior to the onset of pneumonia.

RESULTS

Nearly all immunocompetent mice survived, regardless of which strain of S. aureus was used or which strain of mouse was infected. Among animals with immune depletion or prior immunosuppression, survival was decreased only following neutrophil depletion (26% versus 90% alive at 7 d, P < 0.0001). Compared to immunocompetent animals, neutrophil-depleted mice with S. aureus pneumonia had delayed pulmonary bacterial clearance at 16 and 40 h but had no difference in levels of bacteremia. Neutrophil-depleted mice also had elevated levels of pulmonary monocyte chemotactic protein-1 (822 pg/mL versus 150 pg/mL, P < 0.05). In contrast, pulmonary histological appearance was similar in both groups as was dry/wet lung weight.

CONCLUSIONS

These results suggest that neutrophils play a critical role in the host response to S. aureus pneumonia, and the survival differences observed in neutrophil-depleted mice are associated with alterations in bacterial clearance and pulmonary cytokine response.

Thiols and the chemoprevention of cancer

Thiols such as glutathione interfere with the complex carcinogenic process. Under stress conditions, they scavenge harmful molecules: Glutathione conjugation of electrophilic carcinogens may prevent tumor initiation, and reduced thiols may defend against oxidative stress. Thus, associated chemopreventive strategies involve enhancement of antioxidant or conjugating capacity by increasing the levels of, particularly, glutathione through precursor application or synthesis stimulation and by inducing the corresponding enzymes. The antioxidant potential of thiols is, however, a part of a more general capacity to regulate redox status even in the absence of unequivocal stress conditions. Redox status controls the activities of various cellular signalling proteins through oxidation or reduction of particular sensor structures that are also mostly thiols. The development of feasible chemotherapeutic strategies on the basis of this complex system of redox-sensitive messenger proteins is a goal in ongoing and future research.

Captopril protects mice bone marrow cells against genotoxicity induced by gamma irradiation

The radioprotective effects of captopril were investigated by using the micronucleus test for anticlastogenic and cell proliferation activity. A single intraperitoneal administration of captopril at doses of 10, 25 and 50 mg/kg 1 h prior to gamma irradiation (2 Gy) reduced the frequencies of micronuleated polychromatic erythrocytes (MnPCEs). All three doses of captopril significantly reduced the frequencies of MnPCEs and increased polychromatic erythrocytes (PCE)/PCE+NCE (normochromatic erythrocyte) ratio in mice bone marrow compared to the non-drug-treated irradiated control (p < 0.001). The optimum dose for protection in mouse was 10 mg/kg to protect mice bone marrow 2.18-fold against the clastogenic effects of gamma-irradiation with respect to the non-drug-treated irradiated control. There was a drug dose-response effect of captopril in increasing the PCE/PCE+NCE ratio in bone marrow cells. The maximum protective effect of captopril was at a dose of 25 mg/kg for increasing the PCE/PCE + NCE ratio. Captopril exhibited concentration-dependent antioxidant activity, scavenging > 96% of the 1,1-diphenyl-2-picryl hydrazyl free radicals when used at a concentration of 0.2 mM. In this study captopril reduced lipid peroxidation induced by hydrogen peroxide in mice liver. It appears that captopril, due to its free radical scavenging properties, protects mice bone marrow cells from radiation-induced DNA damage and genotoxicity.