Roflumilast Attenuates Doxorubicin-Induced Cardiotoxicity by Targeting Inflammation and Cellular Senescence in Cardiomyocytes Mediated by SIRT1

4-Deoxy-ε-Pyrromycinone: A Promising Drug/Lead Compound to Treat Tumors

Background

Anthraquinone drugs are widely used in the treatment of tumors. However, multidrug resistance and severe cardiac toxicity limit its use, which have led to the discovery of new analogues. In this paper, 4-Deoxy-ε-pyrromycinone (4-Deo), belonging to anthraquinone compounds, was first been studied with the anti-tumor effects and the safety in vitro and in vivo as a new anti-tumor drug or lead compound.

Methods

The quantitative analysis of 4-Deo was established by UV methodology. The anti-cancer effect of 4-Deo in vitro was evaluated by cytotoxicity experiments of H22, HepG2 and Caco2, and the anti-cancer mechanism was explored by cell apoptosis and cycle. The tumor-bearing mouse model was established by subcutaneous inoculation of H22 cells to evaluate the anti-tumor effect of 4-Deo in vivo. The safety of 4-Deo was verified by the in vitro safety experiments of healthy cells and the in vivo safety experiments of H22 tumor-bearing mice. Tumor tissue sections were labeled with CRT, HMGB1, IL-6 and CD115 to explore the preliminary anti-cancer mechanism by immunohistochemistry.

Results

In vitro experiments demonstrated that 4-Deo could inhibit the growth of H22 by inducing cell necrosis and blocking cells in S phase, and 4-Deo has less damage to healthy cells. In vivo experiments showed that 4-Deo increased the positive area of CRT and HMGB1, which may inhibit tumor growth by triggering immunogenic cell death (ICD). In addition, 4-Deo reduced the positive area of CSF1R, and the anti-tumor effect may be achieved by blocking the transformation of tumor-associated macrophages (TAMs) to M2 phenotype.

Conclusion

In summary, this paper demonstrated the promise of 4-Deo for cancer treatment in vitro and in vivo. This paper lays the foundation for the study of 4-Deo, which is beneficial for the further development anti-tumor drugs based on the lead compound of 4-Deo.

PI3K/AKT signaling activation by roflumilast ameliorates rotenone-induced Parkinson's disease in rats

Parkinson's disease (PD) is the second most common progressive age-related neurodegenerative disorder. Paramount evidence shed light on the role of PI3K/AKT signaling activation in the treatment of neurodegenerative disorders. PI3K/AKT signaling can be activated via cAMP-dependent pathways achieved by phosphodiesterase 4 (PDE4) inhibition. Roflumilast is a well-known PDE4 inhibitor that is currently used in the treatment of chronic obstructive pulmonary disease. Furthermore, roflumilast has been proposed as a favorable candidate for the treatment of neurological disorders. The current study aimed to unravel the neuroprotective role of roflumilast in the rotenone model of PD in rats. Ninety male rats were allocated into six groups as follows: control, rotenone (1.5 mg/kg/48 h, s.c.), L-dopa (22.5 mg/kg, p.o), and roflumilast (0.2, 0.4 or 0.8 mg/kg, p.o). All treatments were administrated for 21 days 1 h after rotenone injection. Rats treated with roflumilast showed an improvement in motor activity and coordination as well as preservation of dopaminergic neurons in the striatum. Moreover, roflumilast increased cAMP level and activated the PI3K/AKT axis via stimulation of CREB/BDNF/TrkB and SIRT1/PTP1B/IGF1 signaling cascades. Roflumilast also caused an upsurge in mTOR and Nrf2, halted GSK-3β and NF-ĸB, and suppressed FoxO1 and caspase-3. Our study revealed that roflumilast exerted neuroprotective effects in rotenone-induced neurotoxicity in rats. These neuroprotective effects were mediated via the crosstalk between CREB/BDNF/TrkB and SIRT1/PTP1B/IGF1 signaling pathways which activates PI3K/AKT trajectory. Therefore, PDE4 inhibition is likely to offer a reliable persuasive avenue in curing PD via PI3K/AKT signaling activation.

Molecular mechanisms mediate roflumilast protective effect against isoprenaline-induced myocardial injury

BACKGROUND

Myocardial necrosis is one of the most common cardiac and pathological diseases. Unfortunately, using the available medical treatment is not sufficient to rescue the myocardium. So that, we aimed in our model to study the possible cardioprotective effect of roflumilast (ROF) in an experimental model of induced myocardial injury using a toxic dose of isoprenaline (ISO) and detecting the role of vascular endothelial growth factor/endothelial nitric oxide synthase (VEGF/eNOS) and cyclic guanosine monophosphate/cyclic adenosine monophosphate/ sirtuin1 (cGMP/cAMP/SIRT1) signaling cascade.

MATERIALS AND METHODS

Animals were divided into five groups; control, ISO given group (150 mg/kg) i.p. on the 4th and 5th day, 3 ROF co-administered groups in different doses (0.25, 0.5, 1 mg/kg/day) for 5 days.

RESULTS

Our data revealed that ISO could induce cardiac toxicity as manifested by significant increases in troponin I, creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), malondialdehyde (MDA), tumor necrosis factor alpha (TNFα), and cleaved caspase-3 with toxic histopathological changes. Meanwhile, there were significant decreases in reduced glutathione (GSH), total antioxidant capacity (TAC), VEGF, eNOS, cGMP, cAMP and SIRT1. However, co-administration of ROF showed significant improvement and normalization of ISO induced cardiac damage.

CONCLUSION

We concluded that ROF successfully reduced ISO induced myocardial injury and this could be attributed to modulation of PDE4, VEGF/eNOS and cGMP/cAMP/SIRT1 signaling pathways with antioxidant, anti-inflammatory, and anti-apoptotic properties.

SGK1 is involved in doxorubicin-induced chronic cardiotoxicity and dysfunction through activation of the NFκB pathway

Breast cancer is the predominant cancer among women worldwide, and chemotherapeutic agents, such as doxorubicin (DOX), have the potential to significantly prolong survival, albeit at the cost of inducing severe cardiovascular toxicity. Inflammation has emerged as a crucial biological process contributing to the remodeling of cardiovascular toxicity. The role of serum glucocorticoid kinase 1 (SGK1) in various inflammatory diseases has been extensively investigated. Here, we studied the molecular mechanisms underlying the function of SGK1 in DOX-induced cardiotoxicity in HL-1 cardiomyocyte cell lines and in a tumor-bearing mouse model. SGK1 was upregulated in the DOX-induced cardiotoxicity model, accompanied by increased levels of inflammatory factors. Furthermore, inhibition of SGK1 suppresses the phosphorylation of nuclear factor-kappa B (NFκB) in cardiomyocytes, which inhibits the production of inflammatory factors and apoptosis of cardiomyocytes, and has cardioprotective effects. Simultaneously, small interfering RNA targeting SGK1 inhibited the proliferation of breast cancer cells. Conversely, overexpression of SGK1 increases the phosphorylation of NFκB and aggravates myocardial injury. In conclusion, our study demonstrates that SGK1 promotes DOX-induced cardiac inflammation and apoptosis by promoting NFκB activity. Our results indicate that inhibiting SGK1 might be an effective treatment strategy that can provide both tumor-killing and cardioprotective functions. Further in vivo research is needed to fully elucidate the effects and mechanisms of combination therapy with SGK1 inhibitors and DOX in breast cancer treatment.

Phloretin alleviates doxorubicin-induced cardiotoxicity through regulating Hif3a transcription via targeting transcription factor Fos

BACKGROUND

Doxorubicin (Dox), a chemotherapeutic agent known for its efficacy, has been associated with the development of severe cardiotoxicity, commonly referred to as doxorubicin-induced cardiotoxicity (DIC). The role and mechanism of action of phloretin (Phl) in cardiovascular diseases are well-established; however, its specific function and underlying mechanism in the context of DIC have yet to be fully elucidated.

OBJECTIVE

This research aimed to uncover the protective effect of Phl against DIC in vivo and in vitro, while also providing a comprehensive understanding of the underlying mechanisms involved.

METHODS

DIC cell and murine models were established. The action targets and mechanism of Phl against DIC were comprehensively examined by systematic network pharmacology, molecular docking, transcriptomics technologies, transcription factor (TF) prediction, and experimental validation.

RESULTS

Phl relieved Dox-induced cell apoptosis in vitro and in vivo. Through network pharmacology analysis, a total of 554 co-targeted genes of Phl and Dox were identified. Enrichment analysis revealed several key pathways including the PI3K-Akt signaling pathway, Apoptosis, and the IL-17 signaling pathway. Protein-protein interaction (PPI) analysis identified 24 core co-targeted genes, such as Fos, Jun, Hif1a, which were predicted to bind well to Phl based on molecular docking. Transcriptomics analysis was performed to identify the top 20 differentially expressed genes (DEGs), and 202 transcription factors (TFs) were predicted for these DEGs. Among these TFs, 10 TFs (Fos, Jun, Hif1a, etc.) are also the co-targeted genes, and 3 TFs (Fos, Jun, Hif1a) are also the core co-targeted genes. Further experiments validated the finding that Phl reduced the elevated levels of Hif3a (one of the top 20 DEGs) and Fos (one of Hif3a's predicted TFs) induced by Dox. Moreover, the interaction between Fos protein and the Hif3a promoter was confirmed through luciferase reporter assays.

CONCLUSION

Phl actively targeted and down-regulated the Fos protein to inhibit its binding to the promoter region of Hif3a, thereby providing protection against DIC.

Recent Advances in the Mechanisms of Cell Death and Dysfunction in Doxorubicin Cardiotoxicity

Despite recent advances in cancer therapy, anthracycline-based combination therapy remains the standardized first-line strategy and has been found to have effective antitumor actions. Anthracyclines are extremely cardiotoxic, which limits the use of these powerful chemotherapeutic agents. Although numerous studies have been conducted on the cardiotoxicity of anthracyclines, the precise mechanisms by which doxorubicin causes cardiomyocyte death and myocardial dysfunction remain incompletely understood. This review highlights recent updates in mechanisms and therapies involved in doxorubicin-induced cardiomyocyte death, including autophagy, ferroptosis, necroptosis, pyroptosis, and apoptosis, as well as mechanisms of cardiovascular dysfunction resulting in myocardial atrophy, defects in calcium handling, thrombosis, and cell senescence. We sought to uncover potential therapeutic approaches to manage anthracycline cardiotoxicity via manipulation of crucial targets involved in doxorubicin-induced cardiomyocyte death and dysfunction.

Doxorubicin-mediated cardiac dysfunction: Revisiting molecular interactions, pharmacological compounds and (nano)theranostic platforms

Although chemotherapy drugs are extensively utilized in cancer therapy, their administration for treatment of patients has faced problems that regardless of chemoresistance, increasing evidence has shown concentration-related toxicity of drugs. Doxorubicin (DOX) is a drug used in treatment of solid and hematological tumors, and its function is based on topoisomerase suppression to impair cancer progression. However, DOX can also affect the other organs of body and after chemotherapy, life quality of cancer patients decreases due to the side effects. Heart is one of the vital organs of body that is significantly affected by DOX during cancer chemotherapy, and this can lead to cardiac dysfunction and predispose to development of cardiovascular diseases and atherosclerosis, among others. The exposure to DOX can stimulate apoptosis and sometimes, pro-survival autophagy stimulation can ameliorate this condition. Moreover, DOX-mediated ferroptosis impairs proper function of heart and by increasing oxidative stress and inflammation, DOX causes cardiac dysfunction. The function of DOX in mediating cardiac toxicity is mediated by several pathways that some of them demonstrate protective function including Nrf2. Therefore, if expression level of such protective mechanisms increases, they can alleviate DOX-mediated cardiac toxicity. For this purpose, pharmacological compounds and therapeutic drugs in preventing DOX-mediated cardiotoxicity have been utilized and they can reduce side effects of DOX to prevent development of cardiovascular diseases in patients underwent chemotherapy. Furthermore, (nano)platforms are used comprehensively in treatment of cardiovascular diseases and using them for DOX delivery can reduce side effects by decreasing concentration of drug. Moreover, when DOX is loaded on nanoparticles, it is delivered into cells in a targeted way and its accumulation in healthy organs is prevented to diminish its adverse impacts. Hence, current paper provides a comprehensive discussion of DOX-mediated toxicity and subsequent alleviation by drugs and nanotherapeutics in treatment of cardiovascular diseases.

The potential beneficial role of Ginkgetin in doxorubicin-induced hepatotoxicity: Elucidating the underlying claim

Doxorubicin (DOX) is a widely used chemotherapeutic agent for various tumors treatment; apart from its chemotherapeutic activity, the traditional usage of DOX has been limited by its adverse effects on multiple organs, mainly hepatotoxicity. The molecular mechanisms underlying DOX hepatotoxicity are mainly due to the production of reactive oxygen species (ROS) inducing oxidative stress, diminishing antioxidant enzymes, apoptosis, inflammation, and mitochondrial dysfunction. Thus, there is an urgent need to develop a therapy that minimizes DOX hepatotoxicity and widens its use in various types of cancers without fear of its serious hepatotoxicity. Ginkgetin (GINK), a natural biflavonoid, exhibits diverse actions, including promising free radical scavenging, antioxidant, and anti-inflammatory activities. So, this study's objectives were to determine whether GINK could mitigate DOX's hepatotoxic effects and look into a putative hepatoprotective molecular pathway. Mice were divided into five groups: Normal control, control GINK 100, Untreated DOX group, and DOX groups treated with GINK (50 and 100 mg/kg) intraperitoneally daily for four days before DOX administration and an additional three days afterward. GINK 100 pretreatment showed marked protection from DOX hepatotoxicity and also attenuation of histopathological structural alterations. These outcomes were corroborated biochemically by a considerable decrease in alanine aminotransferases, aspartate aminotransferase, and alkaline phosphatase levels. GINK significantly augmented silent information regulator 1 and nuclear translocation of NF-E2-related factor 2 and repressed the expression and protein levels of forkhead box protein O1, inducible nitric oxide synthase, and P53 relative to DOX group. GINK alleviated oxidative stress and induced significant anti-inflammatory effects via suppression of interleukin-6, nuclear factor Kabba B, and iNOS respectively. This study is the first to investigate GINK's potentially beneficial effects in acute DOX hepatotoxicity, possibly exhibiting antioxidant, anti-inflammatory, and anti-apoptotic effects by modulation of Sirt1/FOXO-1/NF-κB Signal.

Inflammation and aging: signaling pathways and intervention therapies

Aging is characterized by systemic chronic inflammation, which is accompanied by cellular senescence, immunosenescence, organ dysfunction, and age-related diseases. Given the multidimensional complexity of aging, there is an urgent need for a systematic organization of inflammaging through dimensionality reduction. Factors secreted by senescent cells, known as the senescence-associated secretory phenotype (SASP), promote chronic inflammation and can induce senescence in normal cells. At the same time, chronic inflammation accelerates the senescence of immune cells, resulting in weakened immune function and an inability to clear senescent cells and inflammatory factors, which creates a vicious cycle of inflammation and senescence. Persistently elevated inflammation levels in organs such as the bone marrow, liver, and lungs cannot be eliminated in time, leading to organ damage and aging-related diseases. Therefore, inflammation has been recognized as an endogenous factor in aging, and the elimination of inflammation could be a potential strategy for anti-aging. Here we discuss inflammaging at the molecular, cellular, organ, and disease levels, and review current aging models, the implications of cutting-edge single cell technologies, as well as anti-aging strategies. Since preventing and alleviating aging-related diseases and improving the overall quality of life are the ultimate goals of aging research, our review highlights the critical features and potential mechanisms of inflammation and aging, along with the latest developments and future directions in aging research, providing a theoretical foundation for novel and practical anti-aging strategies.

Roflumilast reduces myocardial ischemia reperfusion injury in vivo and in vitro by activating the AMPK signaling pathway

Myocardial tissue cell damage induced by myocardial ischemia/reperfusion (MI/R) notably elevates the mortality rate, increases the complications of patients with myocardial infarction and decreases reperfusion benefit in patients suffering from acute myocardial infarction. Roflumilast protect against cardiotoxicity. Therefore, the present study aimed to investigate the effect of roflumilast on MI/R injury and the underlying mechanisms. To simulate MI/R in vivo and in vitro, the rat model of MI/R was established and H9C2 cells were subjected to hypoxia/reoxygenation (H/R) induction, respectively. The myocardial infarction areas were observed by 2,3,5-triphenyltetrazolium chloride staining. The myocardial enzyme levels in serum and levels of inflammatory cytokines and oxidative stress markers in cardiac tissue were assessed by corresponding assay kits. The cardiac damage was observed by hematoxylin and eosin staining. The mitochondrial membrane potential in cardiac tissue and H9C2 cells was detected using the JC-1 staining kit. The viability and apoptosis of H9C2 cells were detected by Cell Counting Kit-8 and TUNEL assay, respectively. The levels of inflammatory cytokines, oxidative stress markers and ATP in H/R-induced H9C2 cells were analyzed by corresponding assay kits. Western blotting was used for the estimation of AMP-activated protein kinase (AMPK) signaling pathway-, apoptosis- and mitochondrial regulation-associated protein levels. The mPTP opening was detected using a calcein-loading/cobalt chloride-quenching system. The results indicated that roflumilast decreased MI/R-induced myocardial infarction by alleviating myocardial injury and mitochondrial damage through the activation of the AMPK signaling pathway. In addition, roflumilast mitigated viability damage, alleviated oxidative stress, attenuated the inflammatory response and decreased mitochondrial damage in H/R-induced H9C2 cells by activating the AMPK signaling pathway. However, compound C, an inhibitor of the AMPK signaling pathway, reversed the effect of roflumilast on H/R-induced H9C2 cells. In conclusion, roflumilast alleviated myocardial infarction in MI/R rats and attenuated H/R-induced oxidative stress, inflammatory response and mitochondrial damage in H9C2 cells by activating the AMPK signaling pathway.

Therapeutic opportunities for senolysis in cardiovascular disease

Cellular senescence within the cardiovascular system has, until recently, been understudied and unappreciated as a factor in the development of age-related cardiovascular diseases such as heart failure, myocardial infarction and atherosclerosis. This is in part due to challenges with defining senescence within post-mitotic cells such as cardiomyocytes. However, recent evidence has demonstrated senescent-like changes, including a senescence-associated secretory phenotype (SASP), in cardiomyocytes in response to ageing and cell stress. Other replicating cells, including fibroblasts and vascular smooth muscle cells, within the cardiovascular system have also been shown to undergo senescence and contribute to disease pathogenesis. These findings coupled with the emergence of senolytic therapies, to target and eliminate senescent cells, have provided fascinating new avenues for management of several age-related cardiovascular diseases with high prevalence. In this review, we discuss the role of senescent cells within the cardiovascular system and highlight the contribution of senescence cells to common cardiovascular diseases. We discuss the emerging role for senolytics in cardiovascular disease management while highlighting important aspects of senescence biology which must be clarified before the potential of senolytics can be fully realized.

Intermittent treatment with Apremilast, a phosphodiesterase-4 inhibitor, ameliorates Alzheimer's-like pathology and symptoms through multiple targeting actions in aged T2D rats

BACKGROUND

Apremilast (Apre), a novel phosphodiesterase-4 (PDE4) inhibitor, has been shown to have anti-inflammatory, immunomodulator, neuroprotective and senolytic properties, therefore, Apre like other PDE4 inhibitors may be a promising candidate for treatment of Alzheimer's disease (AD).

OBJECTIVE

To evaluate the effectiveness of Apre on Alzheimer's like pathology and symptoms in an animal model.

METHODS

The effects of Apre and cilostazol, a reference drug, on the behavioral, biochemical, and pathological features of Alzheimer's disease induced by a high-fat/high-fructose diet combined with low-dose streptozotocin (HF/HFr/l-STZ) were investigated.

RESULT

Apre 5 mg/kg IP/day for 3 consecutive days per week for 8 weeks attenuated memory and learning deficits tested by novel object recognition, Morris water maze and passive avoidance tests. Apre treatment significantly decreased the number of degenerating cells, and abnormal suppression of gene expression of AMPA and NMDA receptor subunits in the cortex and hippocampus of the AD rat model compared to rats that received vehicle. A significant decrease in elevated levels of hippocampal amyloid beta, tau-positive cell count, cholinesterase activity, and hippocampal caspase-3, a biomarker of neurodegeneration, was also observed after treatment with Apre in AD rats compared to rats that received placebo. Furthermore, a significant decrease in pro-inflammatory cytokines, oxidative stress, insulin resistance and GSK-3 was demonstrated in AD aged rats treated by Apre.

CONCLUSION

Our findings demonstrate that intermittent treatment with Apre can enhance cognitive function in HF/HFr/l-STZ rats which may be related to decreased pro-inflammatory cytokines, oxidative stress, insulin resistance and GSK-3β.

Activation of the sirtuin silent information regulator 1 pathway inhibits pathological myocardial remodeling

Myocardial remodeling refers to structural and functional disorders of the heart caused by molecular biological changes in the cardiac myocytes in response to neurological and humoral factors. A variety of heart diseases, such as hypertension, coronary artery disease, arrhythmia, and valvular heart disease, can cause myocardial remodeling and eventually lead to heart failure. Therefore, counteracting myocardial remodeling is essential for the prevention and treatment of heart failure. Sirt1 is a nicotinamide adenine dinucleotide⁺-dependent deacetylase that plays a wide range of roles in transcriptional regulation, energy metabolism regulation, cell survival, DNA repair, inflammation, and circadian regulation. It positively or negatively regulates myocardial remodeling by participating in oxidative stress, apoptosis, autophagy, inflammation, and other processes. Taking into account the close relationship between myocardial remodeling and heart failure and the involvement of SIRT1 in the development of the former, the role of SIRT1 in the prevention of heart failure via inhibition of myocardial remodeling has received considerable attention. Recently, multiple studies have been conducted to provide a better understanding of how SIRT1 regulates these phenomena. This review presents the progress of research involving SIRT1 pathway involvement in the pathophysiological mechanisms of myocardial remodeling and heart failure.

Potential Interactions When Prescribing SGLT2 Inhibitors and Intravenous Iron in Combination in Heart Failure

In patients with heart failure, sodium-glucose cotransporter 2 (SGLT2) inhibitors have been shown to decrease hepcidin and ferritin and increase transferrin receptor protein, changes that are typically indicative of worsening absolute iron deficiency, as would be seen with poor dietary intake or gastrointestinal bleeding, neither of which is provoked by SGLT2 inhibitors. Therefore, 2 alternative conceptual frameworks may explain the observed pattern of changes in iron homeostasis proteins. According to the "cytosolic iron depletion hypothesis," the effect of SGLT2 inhibitors to decrease hepcidin and ferritin and increase transferrin receptor is related to a decline in cytosolic Fe²⁺ that occurs after drug-induced erythropoietin-related increase in iron use. Erythropoietin-mimetics (eg, darbepoietin) elicit this type of iron-deficiency pattern of response, and it is typically accompanied by erythropoietin resistance that is alleviated by intravenous iron supplementation. In contrast, according to the "cytosolic iron repletion hypothesis," the effect of SGLT2 inhibitors to decrease hepcidin and ferritin and increase transferrin receptor represents a direct action of these drugs: 1) to reverse inflammation-related increases in hepcidin and ferritin, and, thus, alleviate functional blocks on iron utilization; and 2) to increase in sirtuin-1 signaling, which suppresses hepcidin, accelerates the degradation of ferritin, and up-regulates transferrin receptor protein. Through either or both mechanisms, direct suppression of hepcidin and ferritin would be expected to increase cytosolic Fe²⁺, thus allowing an unattenuated erythrocytic response to erythropoietin without the need for intravenous iron supplementation. The totality of clinical evidence supports the "cytosolic iron repletion hypothesis" because SGLT2 inhibitors elicit a full and sustained erythrocytosis in response to erythropoietin, even in overtly iron-deficient patients and in the absence of intravenous iron therapy. Therefore, the emergence of an iron-deficiency pattern of response during SGLT2 inhibition does not reflect worsening iron stores that are in need of replenishment, but instead, represents potential alleviation of a state of inflammation-related functional iron deficiency that is commonly seen in patients with chronic heart failure. Treatment with intravenous iron may be unnecessary and theoretically deleterious.

Protective effects and mechanisms of lycorine against adriamycin-induced cardiotoxicity

BACKGROUND

Adriamycin (ADR), a high-efficiency, broad-spectrum anthraquinone chemotherapeutic agent, is currently used to treat various malignant tumors and can lead to cumulative, dose-dependent, and irreversible cardiotoxicity. Lycorine (LYC) is a benzyl phenethylamine alkaloid that exerts remarkable therapeutic effects on cancers and sepsis.

PURPOSE

However, researchers have not yet elucidated whether LYC exerts protective effects against cardiotoxicity induced by ADR and the possible molecular mechanisms.

DESIGN

This study established ADR injury models in vitro and in vivo to explore the effects of LYC against cardiotoxicity induced by ADR. The effects of LYC on blood biochemical parameters, cardiac parameters and structure, ADR-related pathophysiological processes, and the SIRT1/PPARγ signal pathway in ADR-injured models, were analyzed using a series of experimental methods.

RESULTS

LYC significantly improved survival rate, blood biochemical parameters (LDH, CK, and BUN), cardiac parameters (SV and CO), mitochondrial dysfunction, and ameliorated oxidative stress, apoptosis, and myocardial fibrosis in ADR-injured mice (p<0.05). Moreover, LYC obviously increased cell viability and reduced oxidative stress, apoptosis, and mitochondrial dysfunction in ADR-injured cells (p<0.05). Furthermore, this study confirmed that the protective effect of LYC on ADR-induced cardiotoxicitymight be mediated by the SIRT1/PPARγ signaling pathway. These results revealed that the beneficial role of LYC on cardiotoxicity induced by ADR were mediated via regulating SIRT1/PPARγ signaling for the first time.

CONCLUSION

These discoveries may provide a theoretical basis for the exploitation of LYC as a potential cardioprotective drug candidate due to its multiple biological functions to reduce ADR-induced cardiotoxicity, but further preclinical and clinical studies are still needed.

Cariporide Attenuates Doxorubicin-Induced Cardiotoxicity in Rats by Inhibiting Oxidative Stress, Inflammation and Apoptosis Partly Through Regulation of Akt/GSK-3β and Sirt1 Signaling Pathway

Background: Doxorubicin (DOX) is a potent chemotherapeutic agent with limited usage due to its cumulative cardiotoxicity. The Na⁺/H⁺ exchanger isoform 1 (NHE1) is a known regulator of oxidative stress, inflammation, and apoptosis. The present study was designed to investigate the possible protective effect of cariporide (CAR), a selective inhibitor of NHE1, against DOX-induced cardiotoxicity in rats.

Methods: Male Sprague-Dawley rats were intraperitoneally injected with DOX to induce cardiac toxicity and CAR was given orally for treatment. The injured H9c2 cell model was established by incubation with DOX in vitro. Echocardiography, as well as morphological and ultra-structural examination were performed to evaluate cardiac function and histopathological changes. The biochemical parameters were determined according to the manufacturer’s guideline of kits. ROS were assessed by using an immunofluorescence assay. The serum levels and mRNA expressions of inflammatory cytokines were measured by using ELISA or qRT-PCR. Cardiac cell apoptosis and H9c2 cell viability were tested by TUNEL or MTT method respectively. The protein expressions of Cleaved-Caspase-3, Bcl-2, Bax, Akt, GSK-3β, and Sirt1 were detected by western blot.

Results: Treatment with CAR protected against DOX-induced body weight changes, impairment of heart function, leakage of cardiac enzymes, and heart histopathological damage. In addition, CAR significantly attenuated oxidative stress and inhibited the levels and mRNA expressions of inflammatory cytokines (TNF-α, IL-6, IL-18, and IL-1β), which were increased by DOX treatment. Moreover, CAR significantly suppressed myocardial apoptosis and Cleaved-Caspase-3 protein expression induced by DOX, which was in agreement with the increased Bcl-2/Bax ratio. Also, DOX suppressed phosphorylation of Akt and GSK-3β, which was significantly reversed by administration of CAR. Furthermore, CAR treatment prevented DOX-induced down-regulation of Sirt1 at the protein level in vitro and in vivo. Finally, Sirt1 inhibitor reversed the protective effects of CAR, as evidenced by reduced cell viability and Sirt1 protein expression in vitro.

Conclusion: Taken together, we provide evidence for the first time in the current study that CAR exerts potent protective effects against DOX-induced cardiotoxicity in rats. This cardio-protective effect is attributed to suppressing oxidative stress, inflammation, and apoptosis, at least in part, through regulation of Akt/GSK-3β and Sirt1 signaling pathway, which has not been reported to date.

Cellular Senescence in Cardiovascular Diseases: A Systematic Review

Aging is a prominent risk factor for cardiovascular diseases, which is the leading cause of death around the world. Recently, cellular senescence has received potential attention as a promising target in preventing cardiovascular diseases, including acute myocardial infarction, atherosclerosis, cardiac aging, pressure overload-induced hypertrophy, heart regeneration, hypertension, and abdominal aortic aneurysm. Here, we discuss the mechanisms underlying cellular senescence and describe the involvement of senescent cardiovascular cells (including cardiomyocytes, endothelial cells, vascular smooth muscle cells, fibroblasts/myofibroblasts and T cells) in age-related cardiovascular diseases. Then, we highlight the targets (SIRT1 and mTOR) that regulating cellular senescence in cardiovascular disorders. Furthermore, we review the evidence that senescent cells can exert both beneficial and detrimental implications in cardiovascular diseases on a context-dependent manner. Finally, we summarize the emerging pro-senescent or anti-senescent interventions and discuss their therapeutic potential in preventing cardiovascular diseases.

Role of acetylation in doxorubicin-induced cardiotoxicity

As a potent chemotherapeutic agent, doxorubicin (DOX) is widely used for the treatment of a variety of cancers However, its clinical utility is limited by dose-dependent cardiotoxicity, and pathogenesis has traditionally been attributed to the formation of reactive oxygen species (ROS). Accordingly, the prevention of DOX-induced cardiotoxicity is an indispensable goal to optimize therapeutic regimens and reduce morbidity. Acetylation is an emerging and important epigenetic modification regulated by histone deacetylases (HDACs) and histone acetyltransferases (HATs). Despite extensive studies of the molecular basis and biological functions of acetylation, the application of acetylation as a therapeutic target for cardiotoxicity is in the initial stage, and further studies are required to clarify the complex acetylation network and improve the clinical management of cardiotoxicity. In this review, we summarize the pivotal functions of HDACs and HATs in DOX-induced oxidative stress, the underlying mechanisms, the contributions of noncoding RNAs (ncRNAs) and exercise-mediated deacetylases to cardiotoxicity. Furthermore, we describe research progress related to several important SIRT activators and HDAC inhibitors with potential clinical value for chemotherapy and cardiotoxicity. Collectively, a comprehensive understanding of specific roles and recent developments of acetylation in doxorubicin-induced cardiotoxicity will provide a basis for improved treatment outcomes in cancer and cardiovascular diseases.