Davallialactone protects against adriamycin-induced cardiotoxicity in vitro and in vivo

Natural Products Counteracting Cardiotoxicity during Cancer Chemotherapy: The Special Case of Doxorubicin, a Comprehensive Review

Cardiotoxicity is a frequent undesirable phenomenon observed during oncological treatment that limits the therapeutic dose of antitumor drugs and thus may decrease the effectiveness of cancer eradication. Almost all antitumor drugs exhibit toxic properties towards cardiac muscle. One of the underlying causes of cardiotoxicity is the stimulation of oxidative stress by chemotherapy. This suggests that an appropriately designed diet or dietary supplements based on edible plants rich in antioxidants could decrease the toxicity of antitumor drugs and diminish the risk of cardiac failure. This comprehensive review compares the cardioprotective efficacy of edible plant extracts and foodborne phytochemicals whose beneficial activity was demonstrated in various models in vivo and in vitro. The studies selected for this review concentrated on a therapy frequently applied in cancer, anthracycline antibiotic-doxorubicin-as the oxidative stress- and cardiotoxicity-inducing agent.

Ginsenoside Re Inhibits ROS/ASK-1 Dependent Mitochondrial Apoptosis Pathway and Activation of Nrf2-Antioxidant Response in Beta-Amyloid-Challenged SH-SY5Y Cells

Accumulation of amyloid-β (Aβ), which results in the formation of senile plaques that cause oxidative damage and neuronal cell death, has been accepted as the major pathological mechanism of Alzheimer’s disease (AD). Hence, inhibition of Aβ-induced oxidative damage and neuronal cell apoptosis represents the effective strategies in combating AD. Ginsenoside Re (Re) has pharmacological effects against Aβ-induced neurotoxicity. However, its molecular mechanism remains elusive. The present study evaluated the effect of Re against Aβ-induced cytotoxicity and apoptosis in SH-SY5Y cells, and investigated the underlying mechanism. We demonstrate that Re inhibits the Aβ-triggered mitochondrial apoptotic pathway, as indicated by maintenance of mitochondrial functional, elevated Bcl-2/Bax ratio, reduced cytochrome c release, and inactivation of caspase-3/9. Re attenuated Aβ-evoked reactive oxygen species (ROS) production, apoptosis signal-regulating kinase 1 (ASK1) phosphorylation, and JNK activation. ROS-scavenging abrogated the ability of Re to alter ASK-1 activation. Simultaneously, inhibition of JNK abolished Re-induced Bax downregulation in Aβ-challenged SH-SY5Y cells. In addition, Re enhanced activation of the nuclear factor-E2-related factor 2 (Nrf2) in Aβ-induced SH-SY5Y cells. Knockdown of Nrf2 by small interfering RNA targeting Nrf2 abolished the protective effect of Re. Our findings indicate that Re could be a potential therapeutic approach for the treatment of AD.

Spironolactone Attenuates Doxorubicin-induced Cardiotoxicity in Rats

INTRODUCTION

In this study, we examined whether spironolactone (SP) could inhibit doxorubicin (DOX)-induced cardiotoxicity in the rat heart.

METHODS

Rats were randomized into four groups (n = 6): (1) the control group; (2) the SP group; (3) the DOX group; and (4) the SP + DOX group. The rats were evaluated for electrocardiography and cardiac function. The cardiac collagen, cardiomyocyte apoptosis, and the remodeling-related proteins were determined.

RESULTS

Rats treated with DOX showed prolongation of QTc and decreased left ventricular ejection fraction (EF) and fractional shortening (FS) (P < 0.05) showed left ventricular end-diastolic dimensions (LVEDD) and left ventricular end-systolic dimensions (LVESD) were significantly increased (P < 0.05). SP prevented these pathophysiological alterations (P < 0.05). In DOX-treated group, cardiac fibrosis, apoptotic cell number, and cardiac collagen volume fraction were higher than control group (P < 0.05); these effects were prevented by cotreatment of SP (P < 0.05). Moreover, the expressions of TGF-β1 and phosphorylated-Smad3 were increased after DOX treatment (P < 0.05) and significantly reduced by coadministration of SP (P < 0.05).

CONCLUSIONS

This study show that SP may have a protective effect on DOX-induced cardiotoxicity.

Protective effect of p-coumaric acid against doxorubicin induced toxicity in H9c2 cardiomyoblast cell lines

Doxorubicin (Dox) has been used for more than four decades to treat cancer, particularly solid tumours and haematological malignancies. However, the administration of this drug is a matter of concern in the clinical community, since Dox therapy is commonly associated with dose-dependent cardiotoxicity. Attempts at alleviating drug generated cardiac damage using naturally occurring compounds with radical scavenging property are a promising area of research. p-Coumaric acid (pCA) is one such compound which has significant antiradical scavenging effect. This study aims to investigate the effect of pre and co-administration of pCA on mitigating or preventing Dox induced cardiotoxicity in vitro using H9c2 cardiomyoblast cell lines. Addition of pCA and Dox were performed for both treatment and control sets on H9c2 cells. Sulphorhodamine B assay was used to study the cytotoxic effect of pCA and Dox. The effect of the drug on cell morphology, cell viability and nuclear damage was studied using AO/EB and DAPI staining. ROS production was studied using DCFH-DA staining. Mitochondrial membrane potential and intracellular calcium levels were assessed by rhodamine 123 and Fura 2AM staining. pCA showed strong ABTS cation radical scavenging activity and FRAP activity in a dose dependent manner. The results showed that Dox has significant cytotoxic effect in a dose dependent manner while pCA, even at higher concentrations did not display any significant cytotoxicity on H9c2 cells. Both pre treatment and co- administration of pCA reduced the drug induced toxic effects on cell morphology and enhanced the number of viable cells in comparison to the Dox treated cells as evident from the AO/EB and DAPI staining images. The Dox induced ROS production was found to be significantly reduced in pCA pre-treated and co-administered cells. Dox induced changes in mitochondrial membrane potential and intracellular calcium levels were remarkably improved following pre and co-treatment of H9c2 cells with pCA. These results clearly suggest that pre-treatment and co-administration of pCA is a promising therapeutic intervention in managing Dox mediated cardiotoxicity.

Cardiovascular effects of low versus high-dose beta-carotene in a rat model

β-carotene (BC), a lipid-soluble tetraterpene precursor to vitamin A, widely distributed in plants, including many used in human diet, has well-known health-enhancing properties, including reducing risk of and treatment for certain diseases. Nevertheless, BC may also act to promote disease through the activity of BC derivatives that form in the presence of external toxicants such as cigarette smoke and endogenously-produced reactive oxygen species. The present investigation evaluates the dose-dependent cardioprotective and possibly harmful properties of BC in a rat model. Adult male rats were gavage-fed BC for 4 weeks, at dosages of either 0, 30 or 150 mg/kg/day. Then, hearts excised from the animals were mounted in a "working heart" apparatus and subjected to 30 min of global ischemia, followed by 120 min of reperfusion. A panel of cardiac functional evaluations was conducted on each heart. Infarct size and total antioxidant capacity of the myocardium were assessed. Heart tissue content of heme oxygenase-1 (HO-1) by Western blot analysis; and potential direct cytotoxic effects of BC by MTT assay were evaluated. Hearts taken from rats receiving 30 mg/kg/day BC exhibited significantly improved heart function at lower reperfusion times, but lost this protection at higher BC dosage and longer reperfusion times. Myocardial HO-1 content was significantly elevated dose-responsively to both BC dosage. Finally, in vitro evaluation of BC on H9c2 cells showed that the agent significantly improved vitality of these cells in a dose range of 2.5-10 μM. Although data presented here do not allow for a comprehensive mechanistic explanation for reduced cardioprotection at high dose BC, it is speculated that since Fe2+ produced as a metabolite of HO-1 activity, may determine whether BC acts as an antioxidant or prooxidant agent, the strong induction of this enzyme in response to ischemia/reperfusion-induced oxidative stress may account for the high-dose BC loss of cardioprotection.

Molecular damage caused by generation of reactive oxygen species in the redox cycle of doxorubicin-transferrin conjugate in human leukemia cell lines

In this study we focused on evaluation of the pro-oxidant properties of doxorubicin-transferrin (DOX-TRF) conjugate and its potency to damage macromolecules which are components of cellular compartments. Our experiments were performed on two human leukemia cell lines: K562 (chronic erythromyeloblastoid leukemia) and CCRF-CEM (acute lymphoblastic leukemia). We determined the reactive oxygen species (ROS) production and programmed cell death (PCD) induction by free DOX and its conjugate. Besides this, the lipid peroxidation and protein damage which can be provoked by DOX alone and DOX-TRF conjugate were assessed. ROS were produced in leukemia cells incubated with free DOX and DOX-TRF conjugate and the extent of apoptosis and necrosis was strongly dependent on the cell line, sensitivity to drug and time of incubation with the investigated compounds. The role of ROS in DOX-TRF conjugate-induced cell death was confirmed by the diminution effects of the antioxidant vitamin C.

Protective effect of resveratrol against doxorubicin-induced cardiac toxicity and fibrosis in male experimental rats

The possible effectiveness of resveratrol, a polyphenol present in different plants comprising berries, grapes and peanuts, on the prevention of doxorubicin-induced cardiac toxicity and fibrosis was investigated. Forty adult male Wistar albino rats were divided into four groups. Group I received normal saline, group II gavaged with resveratrol (20 mg/kg, daily for 4 weeks), group III received doxorubicin (2.5 mg/kg i.p. in six injections for 2 weeks; accumulative dose of 15 mg/kg), and group IV received doxorubicin + resveratrol (starting resveratrol intake 2 weeks before doxorubicin administration). Resveratrol significantly alleviated the increase in left ventricular lipid peroxidation, hydroxyproline, and tumor necrosis factor alpha levels as well as serum creatine kinase-myocardial band (CK-MB) activity and prevented the decrease in body and heart weights in doxorubicin-treated group. However, a marked protection against reduced glutathione content depletion and superoxide dismutase activity reduction was observed in the left ventricles of rats pretreated with resveratrol in combination with doxorubicin. Resveratrol also ameliorated the up-regulation of left ventricular caspase-3 and transforming growth factor-beta1 gene expression as well as left ventricular histopathological changes including necrosis and fibrosis induced by doxorubicin. Collectively, our results suggest that resveratrol provides a significant protection against doxorubicin-induced cardiotoxicity and fibrosis in rats. Therefore, it may be used as a promising cardioprotective agent in patients treated with doxorubicin due to malignant diseases. So, further clinical trials are required to confirm these findings.

Animal models in studies of cardiotoxicity side effects from antiblastic drugs in patients and occupational exposed workers

Cardiotoxicity is an important side effect of cytotoxic drugs and may be a risk factor of long-term morbidity for both patients during therapy and also for staff exposed during the phases of manipulation of antiblastic drugs. The mechanism of cardiotoxicity studied in vitro and in vivo essentially concerns the formation of free radicals leading to oxidative stress, with apoptosis of cardiac cells or immunologic reactions, but other mechanisms may play a role in antiblastic-induced cardiotoxicity. Actually, some new cytotoxic drugs like trastuzumab and cyclopentenyl cytosine show cardiotoxic effects. In this report we discuss the different mechanisms of cardiotoxicity induced by antiblastic drugs assessed using animal models.

Davallialactone from mushroom reduced premature senescence and inflammation on glucose oxidative stress in human diploid fibroblast cells

Mushrooms are both food and a source of natural compounds of biopharmaceutical interest. The purpose of this study was to clarify whether davallialactone from mushroom extract affected the pathogenesis of hyperglycemia oxidative stress and the aging process in human diploid fibroblast (HDF) cells. The high-glucose state with glucose oxidase resulted in glucose oxidative stress, induction of inflammatory molecules, dysfunction of antioxidant molecules, and activation of mitogen-activated protein kinase (MAPKs) and its downstream signaling in old HDF cells. The exposure of glucose oxidative stress in middle-stage cells led to stress-induced premature senescence (SIPS) via senescence-associated β-galactosidase (SA β-gal) activity and displayed replicative senescence phenomena. However, davallialactone reduces the pathogenesis of glucose oxidative stress and the aging process through down-regulation of SA β-gal activity. These results strongly suggest that natural compounds, especially mushroom extract davallialactone, improve the pathogenesis of glucose oxidative stress and the aging process. Hence, davallialactone has potential in the treatment of diabetes mellitus or age-related disease complications.

Davallialactone protects against acetaminophen overdose-induced liver injuries in mice

Oxidative stress is closely associated with acetaminophen (APAP)-induced toxicity. Davallialactone (DAVA), a hispidin analog derived from the mushroom Inonotus xeranticus, has antioxidant properties. This study evaluated whether DAVA plays protective roles against APAP hepatotoxicity in mice. Pretreatments with DAVA (10 mg/kg) prior to exposures of mice to a hepatotoxic dose of 600 mg/kg APAP significantly increased survival rate compared to APAP alone. To verify this effect, mice were treated with 400 mg/kg APAP 30 min after DAVA administration and were then sacrificed after 0.5, 1, 3, and 6 h. APAP alone caused severe liver injuries as characterized by increased plasma GOT and GPT levels, ATP and GSH depletion, and peroxynitrite and 4-HNE formations. These liver damages induced by APAP were significantly attenuated by DAVA pretreatments. The GSH/GSSG ratio nearly recovered to the levels observed in non-APAP-treated mice at 6h after APAP treatment in DAVA-pretreated mice. Furthermore, while hepatic ROS levels were increased by APAP exposures, pretreatments with DAVA completely blocked ROS formation. In addition, APAP-induced sustained activations of JNK and ERK were remarkably reduced by DAVA pretreatment. In conclusion, these results suggest that DAVA plays protective roles against APAP-mediated hepatotoxicity through function as ROS scavenger.

Hispidin analogue davallialactone attenuates carbon tetrachloride-induced hepatotoxicity in mice

In this study the protective effects of davallialactone (1), isolated from Inonotus xeranticus, have been examined against carbon tetrachloride (CCl₄-induced acute liver injury. Mice received subcutaneous injection of 1 (2.5, 5, and 10 mg/kg) for three days before CCl₄ injection (1 mg/kg). Protection from liver injury by 1 was confirmed by the observation of decreased serum transaminases and diminished necrosis of liver tissue. Reduced hepatic injury was very similar to that observed with silymarin, a known hepatoprotective drug used in this work for comparison. The groups treated with 1 had reduced reactive oxygen species (ROS), reduced serum malonyldialdehyde levels, and increased levels of liver Cu/Zn superoxide dismutase, as compared to the CCl₄ control group. The expression of heme oxygenase-1 in the liver tissue was increased and the activity of liver cytochrome P4502E1 was restored in the mice treated with 1. In addition, levels of serum tumor necrosis factor-alpha (TNF-α), inducible NO synthase (iNOS), and cyclooxygenase-2 (COX-2), numbers of macrophage, and cleaved caspase-3-positive hepatocytes were reduced in the groups treated with 1. These findings suggest that davallialactone has protective effects against CCl₄-induced acute liver injury, and this protection is likely due to the suppression of ROS-induced lipid peroxidation and inflammatory response.

Cardioprotective Effects of 20(S)-Ginsenoside Rh2 against Doxorubicin-Induced Cardiotoxicity In Vitro and In Vivo

Doxorubicin (DOX) is considered as one of the best antineoplastic agents. However, its clinical use is restricted by its associated cardiotoxicity, which is mediated by the production of reactive oxygen species. In this study, 20(S)-ginsenoside Rh2 (Rh2) was explored whether it had protective effects against DOX-induced cardiotoxicity. In vitro study on H9C2 cell line, as well as in vivo investigation in one mouse and one rat model of DOX-induced cardiomyopathy, was carried out. The results showed that pretreatment with Rh2 significantly increased the viability of DOX-injured H9C2 cells. In the mouse model, Rh2 could suppress the DOX-induced release of the cardiac enzymes into serum and improved the occurred pathological changes through ameliorating the decreased antioxidant biomolecules and the cumulated lipid peroxidation malondialdehyde in heart tissues. In the rat model, Rh2 could attenuate the change of ECG resulting from DOX administration. Furthermore, Rh2 enhanced the antitumor activity of DOX in A549 cells. Our findings thus demonstrated that Rh2 pretreatment could effectively alleviate heart injury induced by DOX, and Rh2 might act as a novel protective agent in the clinical usefulness of DOX.