Resolvin E1 protects against doxorubicin-induced cardiotoxicity by inhibiting oxidative stress, autophagy and apoptosis by targeting AKT/mTOR signaling

Inhibitory effects and mechanisms of phenolic compounds in rapeseed oil on advanced glycation end product formation in chemical and cellular models in vitro

Sinapic acid (SA), canolol (CAO) and canolol dimer (CAO dimer) are the main phenolic compounds in rapeseed oil. However, their possible efficacy against glycation remains unclear. This study aims to explore the impacts of these substances on the formation of advanced glycation end products (AGEs) based on chemical and cellular models in vitro. Based on fluorescence spectroscopy results, three chemical models of BSA-fructose, BSA-methylglyoxal (MGO), and arginine (Arg)-MGO showed that SA/CAO/CAO dimer could effectively reduce AGE formation but with different abilities. After SA/CAO/CAO dimer incubation, effective protection against BSA protein glycation was observed and three different MGO adducts were formed. In MGO-induced HUVEC cell models, only CAO and CAO dimer significantly inhibited oxidative stress and cell apoptosis, accompanied by the regulation of the Nrf2-HO-1 pathway. During the inhibition, 20 and 12 lipid mediators were reversed in the CAO and CAO dimer groups compared to the MGO group.

Resolution of inflammation, an active process to restore the immune microenvironment balance: A novel drug target for treating arterial hypertension

The resolution of inflammation, the other side of the inflammatory response, is defined as an active and highly coordinated process that promotes the restoration of immune microenvironment balance and tissue repair. Inflammation resolution involves several key processes, including dampening proinflammatory signaling, specialized proresolving lipid mediator (SPM) production, nonlipid proresolving mediator production, efferocytosis and regulatory T-cell (Treg) induction. In recent years, increasing attention has been given to the effects of inflammation resolution on hypertension. Furthermore, our previous studies reported the antihypertensive effects of SPMs. Therefore, in this review, we aim to summarize and discuss the detailed association between arterial hypertension and inflammation resolution. Additional, the association between gut microbe-mediated immune and hypertension is discussed. This findings suggested that accelerating the resolution of inflammation can have beneficial effects on hypertension and its related organ damage. Exploring novel drug targets by focusing on various pathways involved in accelerating inflammation resolution will contribute to the treatment and control of hypertensive diseases in the future.

Genistein alleviates doxorubicin-induced cardiomyocyte autophagy and apoptosis via ERK/STAT3/c-Myc signaling pathway in rat model

Doxorubicin (Dox) is a highly effective anti-neoplastic agent. Still, its utility in the clinic has been hindered by toxicities, including vomiting, hematopoietic suppression and nausea, with cardiotoxicity being the most serious side effect. Genistein (Gen) is a natural product with extensive biological effects, including anti-oxidation, anti-tumor, and cardiovascular protection. This study evaluated whether Gen protected the heart from Dox-induced cardiotoxicity and explored the underlying mechanisms. Male Sprague-Dawley (SD) rats were categorized into control (Ctrl), genistein (Gen), doxorubicin (Dox), genistein 20 mg/kg/day + doxorubicin (Gen20 + Dox) and genistein 40 mg/kg/day + doxorubicin (Gen40 + Dox) groups. Six weeks after injection, immunohistochemistry (IHC), transmission electron microscopy (TEM), and clinical cardiac function analyses were performed to evaluate the effects of Dox on cardiac function and structural alterations. Furthermore, each heart histopathological lesions were given a score of 0-3 in compliance with the articles for statistical analysis. In addition, molecular and cellular response of H9c2 cells toward Dox were evaluated through western blotting, Cell Counting Kit-8 (CCK8), AO staining and calcein AM/PI assay. Dox (5 μM in vitro and 18 mg/kg in vivo) was used in this study. In vivo, low-dose Gen pretreatment protected the rat against Dox-induced cardiac dysfunction and pathological remodeling. Gen inhibited extracellular signal-regulated kinase1/2 (ERK1/2)'s phosphorylation, increased the protein levels of STAT3 and c-Myc, and decreased the autophagy and apoptosis of cardiomyocytes. U0126, a MEK1/2 inhibitor, can mimic the effect of Gen in protecting against Dox-induced cytotoxicity both in vivo and in vitro. Molecular docking analysis showed that Gen forms a stable complex with ERK1/2. Gen protected the heart against Dox-induced cardiomyocyte autophagy and apoptosis through the ERK/STAT3/c-Myc signaling pathway.

Endurance exercise preconditioning alleviates ferroptosis induced by doxorubicin-induced cardiotoxicity through mitochondrial superoxide-dependent AMPKα2 activation

Doxorubicin-induced cardiotoxicity (DIC) adversely impacts patients' long-term health and quality of life. Its underlying mechanism is complex, involving regulatory cell death mechanisms, such as ferroptosis and autophagy. Moreover, it is a challenge faced by patients undergoing cardiac rehabilitation. Endurance exercise (E-Exe) preconditioning effectively counters DIC injury, potentially through the adenosine monophosphate-activated protein kinase (AMPK) pathway. However, detailed studies on this process's mechanisms are scarce. Here, E-Exe preconditioning and DIC models were established using mice and primary cultured adult mouse cardiomyocytes (PAMCs). Akin to ferrostatin-1 (ferroptosis inhibitor), rapamycin (autophagic inducer), and MitoTEMPO (mitochondrial free-radical scavenger), E-Exe preconditioning effectively alleviated Fe2+ accumulation and oxidative stress and improved energy metabolism and mitochondrial dysfunction in DIC injury, as demonstrated by multifunctional, enzymatic, and morphological indices. However, erastin (ferroptosis inducer), 3-methyladenine (autophagic inhibitor), adenovirus-mediated AMPKα2 downregulation, and AMPKα2 inhibition by compound C significantly diminished these effects, both in vivo and in vitro. The results suggest a non-traditional mechanism where E-Exe preconditioning, under mild mitochondrial reactive oxygen species generation, upregulates and phosphorylates AMPKα2, thereby enhancing mitochondrial complex I activity, activating adaptive autophagy, and improving myocardial tolerance to DIC injury. Overall, this study highlighted the pivotal role of mitochondria in myocardial DIC-induced ferroptosis and shows how E-Exe preconditioning activated AMPKα2 against myocardial DIC injury. This suggests that E-Exe preconditioning could be a viable strategy for patients undergoing cardiac rehabilitation.

The Role of Nrf2 and Inflammation on the Dissimilar Cardiotoxicity of Doxorubicin in Two-Time Points: a Cardio-Oncology In Vivo Study Through Time

Doxorubicin (DOX) is a topoisomerase II inhibitor used in cancer therapy. Despite its efficacy, DOX causes serious adverse effects, such as short- and long-term cardiotoxicity. This work aimed to assess the short- and long-term cardiotoxicity of DOX and the role of inflammation and antioxidant defenses on that cardiotoxicity in a mice model. Adult CD-1 male mice received a cumulative dose of 9.0 mg/kg of DOX (2 biweekly intraperitoneal injections (ip), for 3 weeks). One week (1W) or 5 months (5M) after the last DOX administration, the heart was collected. One week after DOX, a significant increase in p62, tumor necrosis factor receptor (TNFR) 2, glutathione peroxidase 1, catalase, inducible nitric oxide synthase (iNOS) cardiac expression, and a trend towards an increase in interleukin (IL)-6, TNFR1, and B-cell lymphoma 2 associated X (Bax) expression was observed. Moreover, DOX induced a decrease on nuclear factor erythroid-2 related factor 2 (Nrf2) cardiac expression. In both 1W and 5M, DOX led to a high density of infiltrating M1 macrophages, but only the 1W-DOX group had a significantly higher number of nuclear factor κB (NF-κB) p65 immunopositive cells. As late effects (5M), an increase in Nrf2, myeloperoxidase, IL-33, tumor necrosis factor-α (TNF-α), superoxide dismutase 2 (SOD2) expression, and a trend towards increased catalase expression were observed. Moreover, B-cell lymphoma 2 (Bcl-2), cyclooxygenase-2 (COX-2), and carbonylated proteins expression decreased, and a trend towards decreased p38 mitogen-activated protein kinase (MAPK) expression were seen. Our study demonstrated that DOX induces adverse outcome pathways related to inflammation and oxidative stress, although activating different time-dependent response mechanisms.

The Role of mTOR in Doxorubicin-Altered Cardiac Metabolism: A Promising Therapeutic Target of Natural Compounds

Doxorubicin (DOX) is commonly used for the treatment of various types of cancer, however can cause serious side effects, including cardiotoxicity. The mechanisms involved in DOX-induced cardiac damage are complex and not yet fully understood. One mechanism is the disruption of cardiac metabolism, which can impair cardiac function. The mammalian target of rapamycin (mTOR) is a key regulator of cardiac energy metabolism, and dysregulation of mTOR signaling has been implicated in DOX-induced cardiac dysfunction. Natural compounds (NCs) have been shown to improve cardiac function in vivo and in vitro models of DOX-induced cardiotoxicity. This review article explores the protective effects of NCs against DOX-induced cardiac injury, with a focus on their regulation of mTOR signaling pathways. Generally, the modulation of mTOR signaling by NCs represents a promising strategy for decreasing the cardiotoxic effects of DOX.

Resolvin E1/ChemR23 Protects Against Hypertension and Vascular Remodeling in Angiotensin II-Induced Hypertensive Mice

BACKGROUND

Inflammation plays a critical role in the development of hypertension and vascular remodeling. Resolvin E1 (RvE1), as one of the specialized proresolving lipid mediators, promotes inflammation resolution by binding with a G protein-coupled receptor, ChemR23 (chemerin receptor 23). However, whether RvE1/ChemR23 regulates hypertension and vascular remodeling is unknown.

METHODS

Hypertension in mice was induced by Ang II (angiotensin II) infusion (750 ng/kg per minute), and RvE1 (2 µg/kg per day) was administered through intraperitoneal injection. Loss of ChemR23 was achieved by mice receiving intravenous injection of adeno-associated virus 9-encoding shRNA against ChemR23.

RESULTS

Aortic ChemR23 expression was increased in Ang II-induced hypertensive mice and that ChemR23 was mainly expressed on vascular smooth muscle cells (VSMCs). RvE1 lowered blood pressure, reduced aortic media thickness, attenuated aortic fibrosis, and mitigated VSMC phenotypic transformation and proliferation in hypertensive mice, which were all reversed by the knockdown of ChemR23. Moreover, RvE1 reduced the aortic infiltration of macrophages and T cells, which was also reversed by ChemR23 knockdown. RvE1 inhibited Ccl5 expression in VSMCs via the AMPKα (AMP-activated protein kinase α)/Nrf2 (nuclear factor E2-related factor 2)/canonical NF-κB (nuclear factor κB) pathway, thereby reducing the infiltration of macrophages and T cells. The AMPKα/Nrf2 pathway also mediated the effects of RvE1 on VSMC phenotypic transformation and proliferation. In patients with hypertension, the serum levels of RvE1 and other eicosapentaenoic acid-derived metabolites were significantly decreased.

CONCLUSIONS

RvE1/ChemR23 ameliorated hypertension and vascular remodeling by activating AMPKα/Nrf2 signaling, which mediated immune cell infiltration by inhibiting the canonical NF-κB/Ccl5 pathway, and regulated VSMC proliferation and phenotypic transformation. RvE1/ChemR23 may be a potential therapeutic target for hypertension.

Alleviation of doxorubicin-induced cardiotoxicity in rat by mesenchymal stem cells and olive leaf extract via MAPK/ TNF-α pathway: Preclinical, experimental and bioinformatics enrichment study

BACKGROUND

Toxic cardiomyopathies were a potentially fatal adverse effect of anthracycline therapy.

AIM

This study was conducted to demonstrate the pathogenetic, morphologic, and toxicologic effects of doxorubicin on the heart and to investigate how the MAPK /TNF-α pathway can be modulated to improve doxorubicin-Induced cardiac lesions using bone marrow-derived mesenchymal stem cells (BM-MSCs) and olive leaf extract (OLE).

METHODS

During the study, 40 adult male rats were used. Ten were used to donate MSCs, and the other 30 were split into 5 equal groups: Group I was the negative control, Group II obtained oral OLE, Group III obtained an intraperitoneal cumulative dose of DOX (12 mg/kg) in 6 equal doses of 2 mg/kg every 48 h for 12 days, Group IV obtained intraperitoneal DOX and oral OLE at the same time, and Group V obtained intraperitoneal DOX and BM-MSCs through the tail vein at the same time for 12 days. Four weeks after their last dose of DOX, the rats were euthanized. By checking the bioinformatic databases, a molecularly targeted path was selected. Then the histological, immunohistochemistry, and gene expression of ERK, JNK, NF-κB, IL-6, and TNF-α were done.

RESULTS

Myocardial immunohistochemistry revealed severe fibrosis, cell degeneration, increased vimentin, and decreased CD-31 expression in the DOX-treated group, along with a marked shift in morphometric measurements, a disordered ultrastructure, and overexpression of inflammatory genes (ERK, NF-κB, IL-6, and TNF-α), oxidative stress markers, and cardiac biomarkers. Both groups IV and V displayed reduced cardiac fibrosis or inflammation, restoration of the microstructure and ultrastructure of the myocardium, downregulation of inflammatory genes, markers of oxidative stress, and cardiac biomarkers, a notable decline in vimentin, and an uptick in CD-31 expression. In contrast to group IV, group V showed a considerable beneficial effect.

CONCLUSION

Both OLE and BM-MSCs showed an ameliorating effect in rat models of DOX-induced cardiotoxicity, with BM-MSCs showing a greater influence than OLE.

Macrophage neogenin deficiency exacerbates myocardial remodeling and inflammation after acute myocardial infarction through JAK1-STAT1 signaling

Immune response plays a crucial role in post-myocardial infarction (MI) myocardial remodeling. Neogenin (Neo1), a multifunctional transmembrane receptor, plays a critical role in the immune response; however, whether Neo1 participates in pathological myocardial remodeling after MI is unclear. Our study found that Neo1 expression changed significantly after MI in vivo and after LPS + IFN-γ stimulation in bone marrow-derived macrophages (BMDMs) in vitro. Neo1 functional deficiency (using a neutralizing antibody) and macrophage-specific Neo1 deficiency (induced by Neo1flox/flox;Cx3cr1cre mice) increased infarction size, enhanced cardiac fibrosis and cardiomyocyte apoptosis, and exacerbated left ventricular dysfunction post-MI in mice. Mechanistically, Neo1 deficiency promoted macrophage infiltration into the ischemic myocardium and transformation to a proinflammatory phenotype, subsequently exacerbating the inflammatory response and impairing inflammation resolution post-MI. Neo1 deficiency regulated macrophage phenotype and function, possibly through the JAK1-STAT1 pathway, as confirmed in BMDMs in vitro. Blocking the JAK1-STAT1 pathway with fludarabine phosphate abolished the impact of Neo1 on macrophage phenotype and function, inflammatory response, inflammation resolution, cardiomyocyte apoptosis, cardiac fibrosis, infarction size and cardiac function. In conclusion, Neo1 deficiency aggravates inflammation and left ventricular remodeling post-MI by modulating macrophage phenotypes and functions via the JAK1-STAT1 signaling pathway. These findings highlight the anti-inflammatory potential of Neo1, offering new perspectives for therapeutic targets in MI treatment. Neo1 deficiency aggravated inflammation and left ventricular remodeling after MI by modulating macrophage phenotypes and functions via the JAK1-STAT1 signaling pathway.

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.

Resolvin D2 and its receptor GPR18 in cardiovascular and metabolic diseases: A promising biomarker and therapeutic target

Accumulating evidence suggests that inflammation plays an important role in the pathophysiology of the initiation and progression of cardiovascular and metabolic diseases (CVMDs). Anti-inflammation strategies and those that promote inflammation resolution have gradually become potential therapeutic approaches for CVMDs. Resolvin D2 (RvD2), a specialized pro-resolving mediator, exerts anti-inflammatory and pro-resolution effects through its receptor GPR18, a G protein-coupled receptor. Recently, the RvD2/GPR18 axis has received more attention due to its protective role in CVMDs, including atherosclerosis, hypertension, ischaemiareperfusion, and diabetes. Here, we introduce basic information about RvD2 and GPR18, summarize their roles in different immune cells, and review the therapeutic potential of the RvD2/GPR18 axis in CVMDs. In summary, RvD2 and its receptor GPR18 play an important role in the occurrence and development of CVMDs and are potential biomarkers and therapeutic targets.

Activation of AMPKα2 attenuated doxorubicin-induced cardiotoxicity via inhibiting lipid peroxidation associated ferroptosis

Ferroptosis has been suggested to involve in doxorubicin (DOX)-induced cardiotoxicity. However, the underlying mechanisms and regulatory targets of cardiomyocyte ferroptosis remains to be understood. This study demonstrated that the up-regulation of ferroptosis associated proteins genes were accompanied with the down-regulation of AMPKα2 phosphorylation in DOX treated mouse heart or neonatal rat cardiomyocytes (NRCMs). AMPKα2 knockout (AMPKα2-/-) significantly exacerbated mouse cardiac dysfunction, increased mortality, promoting ferroptosis associated mitochondrial injuries, enhanced ferroptosis associated proteins and genes expression, and lead to accumulation of lactate dehydrogenase (LDH) and malondialdehyde (MDA) in mouse serum and hearts respectively. Ferrostatin-1 administration markedly improved cardiac function, decreased mortality, inhibited mitochondrial injuries and ferroptosis associated proteins and genes expression, and depressed accumulation of LDH and MDA in DOX treated AMPKα2-/- mouse. Moreover, Adeno-associated virus serotype 9 AMPKα2 (AAV9-AMPKα2) or AICAR treatment mediated AMPKα2 activation could significantly improve cardiac function and depress ferroptosis in mouse. AMPKα2 activation or silence could also inhibit or promote ferroptosis associated injuries in DOX treated NRCMs respecitively. Mechanistically, AMPKα2/ACC mediated lipid metabolism has been suggested to involve in regulating DOX-treatment induced ferroptosis other than mTORC1 or autophagy dependent pathway. The metabolomics analysis exhibited that AMPKα2-/- significantly enhanced accumulation of polyunsaturated fatty acids (PFAs), oxidized lipid, and phosphatidylethanolamine (PE). Finally, this study also demonstrated that metformin (MET) treatment could inhibit ferroptosis and improve cardiac function via activating AMPKα2 phosphorylation. The metabolomics analysis exhibited that MET treatment significantly depressed PFAs accumulation in DOX treated mouse hearts. Collectively, this study suggested that AMPKα2 activation might protect against anthracycline chemotherapeutic drugs mediated cardiotoxicity via inhibiting ferroptosis.

The Role of Specialized Pro-Resolving Lipid Mediators in Inflammation-Induced Carcinogenesis

Cancer is a process involving cell mutation, increased proliferation, invasion, and metastasis. Over the years, this condition has represented one of the most concerning health problems worldwide due to its significant morbidity and mortality. At present, the incidence of cancer continues to grow exponentially. Thus, it is imperative to open new avenues in cancer research to understand the molecular changes driving DNA transformation, cell-to-cell interaction derangements, and immune system surveillance decay. In this regard, evidence supports the relationship between chronic inflammation and cancer. In light of this, a group of bioactive lipids derived from polyunsaturated fatty acids (PUFAs) may have a position as novel anti-inflammatory molecules known as the specialized pro-resolving mediators (SPMs), a group of pro-resolutive inflammation agents that could improve the anti-tumor immunity. These molecules have the potential role of chemopreventive and therapeutic agents for various cancer types, and their effects have been documented in the scientific literature. Thus, this review objective centers around understanding the effect of SPMs on carcinogenesis and their potential therapeutic effect.

Microglia-Mediated Neuroimmune Response Regulates Cardiac Remodeling After Myocardial Infarction

Background Sympathetic hyperactivity contributes to pathological remodeling after myocardial infarction (MI). However, the mechanisms underlying the increase in sympathetic activity remain unknown. Microglia are the predominant immune cells in the central nervous system and can regulate sympathetic neuron activity through neuroimmune response in the hypothalamic paraventricular nucleus. The present study aimed to investigate whether microglia-mediated neuroimmune response can regulate sympathetic activity and cardiac remodeling after MI. Methods and Results PLX3397 (pexidartinib) was used to deplete central microglia via intragastric injection or intracerebroventricular injection. After that, MI was induced by ligation of the left anterior descending coronary artery. Our study showed that MI resulted in the activation of microglia in the paraventricular nucleus. Microglia depletion, which was induced by PLX3397 treatment via intragastric injection or intracerebroventricular injection, improved cardiac function, reduced infarction size, and attenuated cardiomyocyte apoptosis, fibrosis, pathological electrical remodeling, and myocardial inflammation after MI. Mechanistically, these protective effects were associated with an attenuated neuroimmune response in the paraventricular nucleus, which contributed to the decrease of sympathetic activity and attenuation of sympathetic remodeling in the heart. However, intragastric injection with PLX3397 obviously depleted macrophages and induced neutrophil and T-lymphocyte disorders in the heart, blood, and spleen. Conclusions Microglia depletion in the central nervous system attenuates pathological cardiac remodeling after MI by inhibiting neuroimmune response and sympathetic activity. Intragastric administration of PLX3397 leads to serious deleterious effects in peripheral immune cells, especially macrophages, which should be a cause for concern in animal experiments and clinical practice.

Hydrogen inhalation enhances autophagy via the AMPK/mTOR pathway, thereby attenuating doxorubicin-induced cardiac injury

AIMS

Doxorubicin is a drug widely used in clinical cancer treatment, but severe cardiotoxicity limits its clinical application. Autophagy disorder is an important factor in the mechanism of doxorubicin-induced cardiac injury. As the smallest molecule in nature, hydrogen has various biological effects such as anti-oxidation, anti-apoptosis and regulation of autophagy. Hydrogen therapy is currently considered to be an emerging therapeutic method, but the effect and mechanism of hydrogen on doxorubicin-induced myocardial injury have not been determined. The purpose of this study was to investigate the protective effect of hydrogen inhalation on doxorubicin-induced chronic myocardial injury and its effect and mechanism on autophagy.

METHODS

In this study, we established a chronic heart injury model by intraperitoneal injection of doxorubicin in rats for 30 days, accumulating 20 mg/kg. The effect of hydrogen inhalation on the cardiac function in rats was explored by echocardiography, Elisa, and H&E staining. To clarify the influence of autophagy, we detected the expression of LC3 and related autophagy proteins in vivo and in vitro by immunofluorescence and western blot.In order to further explore the mechanism of autophagy, we added pathway inhibitors and used western blot to preliminarily investigate the protective effect of hydrogen inhalation on myocardial injury caused by doxorubicin.

RESULTS

Hydrogen inhalation can improve doxorubicin-induced cardiac function decline and pathological structural abnormalities in rats. It was confirmed by immunofluorescence that hydrogen treatment could restore the expression of autophagy marker protein LC3 (microtubule-associated protein 1 light chain 3) in cardiomyocytes reduced by doxorubicin, while reducing cardiomyocyte apoptosis. Mechanistically, Western blot results consistently showed that hydrogen treatment up-regulated the ratio of p-AMPK (phosphorylated AMP-dependent protein kinase) to AMPK and down-regulated p-mTOR (phosphorylated mammalian target of rapamycin) and mTOR ratio.

CONCLUSIONS

These results suggest that hydrogen inhalation can activate autophagy through the AMPK/mTOR pathway and protect against myocardial injury induced by doxorubicin. Hydrogen inhalation therapy may be a potential treatment for doxorubicin-induced myocardial injury.

IL-27p28 knockout aggravates Doxorubicin-induced cardiotoxicity by regulating Macrophage polarization

BACKGROUND

Several interleukins (ILs) have been demonstrated to participate in cardiac injury. This study aimed to investigate whether IL-27p28 plays a regulatory role in doxorubicin (DOX)-induced cardiac injury by regulating inflammation and oxidative stress.

METHODS

Dox was used to establish a mouse cardiac injury model, and IL-27p28 was knocked out to observe its role in cardiac injury. In addition, monocytes were adoptively transferred to clarify whether monocyte-macrophages mediate the regulatory role of IL-27p28 in DOX-induced cardiac injury.

RESULTS

IL-27p28 knockout significantly aggravated DOX-induced cardiac injury and cardiac dysfunction. IL-27p28 knockout also upregulated the phosphorylation levels of p65 and STAT1 and promoted M1 macrophage polarization in DOX-treated mice, which increased cardiac inflammation and oxidative stress. Moreover, IL-27p28-knockout mice that were adoptively transferred WT monocytes exhibited worse cardiac injury and cardiac dysfunction and higher cardiac inflammation and oxidative stress.

CONCLUSIONS

IL-27p28 knockdown aggravates DOX-induced cardiac injury by worsening the M1 macrophage/M2 macrophage imbalance and its associated inflammatory response and oxidative stress.

SIRT3 attenuates doxorubicin-induced cardiotoxicity by inhibiting NLRP3 inflammasome via autophagy

Doxorubicin (DOX) is a highly effective and extensively used chemotherapeutic drug but is limited by its cardiotoxicity. In our previous study, we showed that DOX-induced cardiotoxicity (DIC) triggers autophagy and pyroptosis. Sirtuin 3(SIRT3) is an NAD + -dependent deacetylase of the mitochondria that regulates autophagy. However, it is unknown if the protective effects of SIRT3 on DOX-induced cardiotoxicity involve the inhibition of NLRP3 inflammasome activation. In this study, we constructed in vivo and in vitro DIC models to investigate the effects and potential mechanisms of SIRT3 on DIC. We found that the overexpression of SIRT3 remarkably attenuated DIC through inhibition of the NLRP3 inflammasome. Moreover, we found that the overexpression of SIRT3 restored the dynamic balance of autophagosome/autolysosomes by targeting the mTOR/ULK1 signaling pathway. Application of the mTOR agonist MHY1485 further demonstrated that SIRT3 inhibited NLRP3 inflammasome activation by regulating autophagy. Collectively, the results suggest that SIRT3 effectively attenuates the cardiotoxicity of DOX and provides a theoretical foundation for further exploration of DIC.

Protective effect of gallic acid on doxorubicin-induced ovarian toxicity in mouse

The aims of the present study were to evaluate the protective effects of gallic acid against doxorubicin-induced ovarian toxicity in mice, and to verify the possible involvement of PI3K and mTOR signaling pathway members (PTEN, Akt, FOXO3a and rpS6) in the gallic acid protective actions. Mice were pretreated with NaCl (0.15 M, p.o.) (control and doxorubicin groups) or gallic acid (50, 100 or 200 mg/kg body weight, p.o.) once daily, for 5 days, and on the third day of treatment, after 1 h of treatment administration, the mice received saline solution (i.p.) (control group) or doxorubicin (10 mg/kg of body weight, i.p.). Next, the ovaries were harvested for histological (follicular morphology and activation), fluorescence (GSH and mitochondrial activity), and immunohistochemical (PCNA, cleaved caspase-3, TNF-α, p-PTEN, Akt, p-Akt, p-rpS6 and p-FOXO3a) analyses. The results showed that cotreatment with 50 mg/kg gallic acid plus doxorubicin preserved the percentage of normal follicles and cell proliferation, reduced the percentage of cleaved caspase-3 follicles, prevented inflammation, and increased GSH concentrations and mitochondrial activity compared to doxorubicin treatment alone. Furthermore, cotreatment 50 mg/kg gallic acid plus doxorrubicin increased expression of Akt, p-Akt, p-rpS6 and p-FOXO3a compared to the doxorubicin alone. In conclusion, 50 mg/kg gallic acid protects the mouse ovary against doxorubicin-induced damage by improving GSH concentrations and mitochondrial activity and cellular proliferation, inhibiting inflammation and apoptosis, and regulating PI3K and mTOR signaling pathway.

Resolution of depression: antidepressant actions of resolvins

Major depressive disorder, one of the most widespread mental illnesses, brings about enormous individual and socioeconomic consequences. Conventional monoaminergic antidepressants require weeks to months to produce a therapeutic response, and approximately one-third of the patients fail to respond to these drugs and are considered treatment-resistant. Although recent studies have demonstrated that ketamine, an N-methyl-D-aspartate receptor antagonist, produces rapid antidepressant effects in treatment-resistant patients, it also has undesirable side effects. Hence, rapid-acting antidepressants that have fewer adverse effects than ketamine are urgently required. D-series (RvD1-RvD6) and E-series (RvE1-RvE4) resolvins are endogenous lipid mediators derived from docosahexaenoic and eicosapentaenoic acids, respectively. These mediators reportedly play a pivotal role in the resolution of acute inflammation. In this review, we reveal that intracranial infusions of RvD1, RvD2, RvE1, RvE2, and RvE3 produce antidepressant-like effects in various rodent models of depression. Moreover, the behavioral effects of RvD1, RvD2, and RvE1 are mediated by the activation of the mechanistic target of rapamycin complex 1, which is essential for the antidepressant-like actions of ketamine. Finally, we briefly provide our perspective on the possible role of endogenous resolvins in stress resilience.

Reversing multi-drug resistance by polymeric metformin to enhance antitumor efficacy of chemotherapy

Multi-drug resistance (MDR) in breast cancer poses a great threat to chemotherapy. The expression and function of the ATP binding cassette (ABC) transporter are the major cause of MDR. Herein, a linear polyethylene glycol (PEI) conjugated with dicyandiamide, which called polymeric metformin (PolyMet), was successfully synthesized as a simple and biocompatible polymer of metformin. PolyMet showed the potential to reverse MDR by inhibiting the efflux of the substrate of ATP-binding cassette (ABC) transporter from DOX resistant MCF-7 cells (MCF-7/DOX). To test its MDR reversing effect, PolyMet was combined with DOX to treat mice carrying MCF-7/DOX xenografts. In order to decrease the toxicities of DOX and delivery PolyMet and DOX to tumor at the same time, PolyMet was complexed with poly-γ-glutamic acid-doxorubicin (PGA-DOX) electrostatically at the optimal ratio of 2:3, which were further coated with lipid membrane to form lipid/PolyMet-(PGA-DOX) nanoparticles (LPPD). The particle size of LPPD was 165.8 nm, and the zeta potential was +36.5 mV. LPPD exhibited favorable cytotoxicity and cellular uptake in MCF-7/DOX. Meanwhile, the bioluminescence imaging and immunohistochemical analysis indicated that LPPD effectively conquered DOX-associated MDR by blocking ABC transporters (ABCB1 and ABCC1) via PolyMet. Remarkably, LPPD significantly inhibited the tumor growth and lowered the systemic toxicity in a murine MCF-7/DOX tumor model. This is the first time to reveal that PolyMet can enhance the anti-tumor efficacy of DOX by dampening ABC transporters and activating the AMPK/mTOR pathway, which is a promising strategy for drug-resistant breast cancer therapy.

Resolvin E1 attenuates doxorubicin-induced cardiac fibroblast senescence: A key role for IL-1β

Cardiac fibroblasts (CFs) undergo senescence in reaction to different stressors, leading to a poor prognosis of cardiac disease. Doxorubicin (Doxo) is an antineoplastic drug with strong cardiotoxic effects, which induces IL-1β secretion and thus, triggers a potent pro-inflammatory response. Doxo induces CFs senescence; however, the mechanisms are not fully understood. Different pharmacological strategies have been used to eliminate senescent cells by inducing their apoptosis or modifying their secretome. However, Resolvin E1 (RvE1), a lipid derivative resolutive mediator with potent anti-inflammatory effects has not been used before to prevent CFs senescence. CFs were isolated from adult male C57BL/6J mice and subsequently stimulated with Doxo, in the presence or absence of RvE1. Senescence-associated β-galactosidase activity (SA-β-gal), γ-H2A.X, p53, p21, and senescence-associated secretory phenotype (SASP) were evaluated. The involvement of the NLRP3 inflammasome/interleukin-1 receptor (IL-1R) signaling pathway on CFs senescence was studied using an NLRP3 inhibitor (MCC950) and an endogenous IL-1R antagonist (IR1A). Doxo is able to trigger CFs senescence, as evidenced by an increase of γ-H2A.X, p53, p21, and SA-β-gal, and changes in the SASP profile. These Doxo effects were prevented by RvE1. Doxo triggers IL-1β secretion, which was dependent on NLRP3 activation. Doxo-induced CFs senescence was partially blocked by MCC950 and IR1A. In addition, IL-1β also triggered CFs senescence, as evidenced by the increase of γ-H2A.X, p53, p21, SA-β-gal activity, and SASP. All these effects were also prevented by RvE1 treatment. CONCLUSION: These data show the anti-senescent role of RvE1 in Doxo-induced CFs senescence, which could be mediated by reducing IL-1β secretion.

Isoorientin attenuates doxorubicin-induced cardiac injury via the activation of MAPK, Akt, and Caspase-dependent signaling pathways

BACKGROUND

Chemotherapy drugs especially anthracyclines are widely used in the treatment of hematological malignancies and solid tumors. However, their clinical application is limited by dose-dependent and irreversible heart injury, which increases the risk of congestive heart failure and heart-related mortality.

PURPOSE

This study aims to investigate the effect and mechanism of the natural flavonoid isoorientin (ISO) combined with doxorubicin (DOX) on the proliferation of tumor cells and improve the survival rate of DOX-injured cardiomyocytes.

STUDY DESIGN/METHODS

Cardiomyocyte H9c2 and a variety of tumor cells were used to evaluate the protective effect of ISO on DOX-induced myocardial injury and enhance the anticancer effects of DOX. DOX chemotherapy-injured mice were used to evaluate the cardioprotective effect of ISO.

RESULTS

The antiproliferation of DOX on Hela, HepG2, HT-29, and A549 cells could be increased synergistically when cotreated with ISO in vitro. ISO could also improve the survival rate of DOX-injured cardiomyocytes by reducing reactive oxygen species, maintaining mitochondrial function, and inhibiting apoptosis. In mice receiving DOX, a protective effect on myocardial tissue, which was reflected by improved survival state of mice receiving chemotherapy, was observed. The ECG, myocardial zymogram data, HE staining, and TEM observation of myocardial tissue sections showed that ISO had a dose-dependent protective effect on the mouse hearts injured by DOX. Network pharmacology and cardiomyocyte proteomics were used to seek for related target proteins to reveal the protective mechanism of ISO on mouse models, and some potential targets (including caspase-3, EGFR, MAPK1, ESR1, CDC42, STAT1, JAK2, LCK, and CDK2) were generated. Western blotting was further used to verify that ISO upregulated Nrf2 and TGF-β3 by downregulating the phosphorylation levels of JNK and p38 proteins on the MAPK pathway and the Akt and Stat3 expression levels. The downregulation of cleaved caspase-3 and upregulation of Bcl-xl by ISO further confirmed its inhibition on caspase-dependent cardiomyocyte apoptosis.

CONCLUSION

ISO could be a potential synergistic anticancer agent with a favorable property of reducing the cardiotoxicity for DOX, and the effect mechanism could refer to the inhibition of ISO on MAPK and caspase-dependent apoptosis pathways.

Maresin-1 and Its Receptors RORα/LGR6 as Potential Therapeutic Target for Respiratory Diseases

Maresin-1 is one of the representative specialized pro-resolving mediators that has shown beneficial effects in inflammatory disease models. Recently, two distinct types of receptor molecules were discovered as the targets of maresin-1, further revealing the pro-resolution mechanism of maresin-1. One is retinoic acid-related orphan receptor α (RORα) and the another one is leucine-rich repeat domain-containing G protein-coupled receptor 6 (LGR6). In this review, we summarized the detailed role of maresin-1 and its two different receptors in respiratory diseases. RORα and LGR6 are potential targets for the treatment of respiratory diseases. Future basic research and clinical trials on MaR1 and its receptors should provide useful information for the treatment of respiratory diseases.

RESOLVIN E1 ATTENUATES DOXORUBICIN-INDUCED ENDOTHELIAL SENESCENCE BY MODULATING NLRP3 INFLAMMASOME ACTIVATION

Endothelial cell senescence contributes to chronic inflammation and endothelial dysfunction, while favoring cardiovascular disorders and frailty. Senescent cells acquire a pro-inflammatory secretory phenotype that further propagates inflammation and senescence to neighboring cells. Cell senescence can be provoked by plethora of stressors, including inflammatory molecules and chemotherapeutic drugs. Doxorubicin (Doxo) is a powerful anthracycline anticancer drug whose clinical application is constrained by a dose-limiting cardiovascular toxicity. We here investigated whether cell senescence can contribute to the vascular damage elicited by Doxo. In human umbilical vein endothelial cells (HUVEC) cultures, Doxo (10-100 nM) increased the number of SA-β-gal positive cells and the levels of γH2AX, p21 and p53, used as markers of senescence. Moreover, we identified Doxo-induced senescence to be mediated by the nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome, a key player of the immune innate system capable of releasing interleukin (IL)-1β. In fact, IL-1β itself mimicked the stimulatory action of Doxo on both NLRP3 activation and cellular senescence, while the pharmacological blockade of IL-1 receptors markedly attenuated the pro-senescence effects of Doxo. In search of additional pharmacological strategies to attenuate Doxo-induced endothelial senescence, we identified resolvin E1 (RvE1), an endogenous pro-resolving mediator, as capable of reducing cell senescence induced by both Doxo and IL-1β by interfering with the increased expression of pP65, NLRP3, and pro-IL-1β proteins and with the formation of active NLRP3 inflammasome complexes. Overall, RvE1 and the blockade of the NLRP3 inflammasome-IL-1β axis may offer a novel therapeutic approach against Doxo-induced cardiovascular toxicity and subsequent sequelae.

Choline Protects the Heart from Doxorubicin-Induced Cardiotoxicity through Vagal Activation and Nrf2/HO-1 Pathway

Choline is a precursor of the major neurotransmitter acetylcholine and has been demonstrated beneficial in diverse models of cardiovascular disease. Here, we sought to verify that choline protects the heart from DOX-induced cardiotoxicity and the underlying mechanisms. The results showed that DOX treatment decreased left ventricular ejection fraction and fractional shortening and increased serum cardiac markers and myocardial fibrosis, which were alleviated by cotreatment with choline. DOX-induced cardiotoxicity was accompanied by increases in oxidative stress, inflammation, and apoptosis, which were rectified by choline cotreatment. Levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme-oxygenase-1 (HO-1), which are antioxidant markers, were lowered by DOX and upregulated by choline. Moreover, DOX significantly decreased serum acetylcholine levels and the high-frequency component of heart rate variability and increased serum norepinephrine levels and the low-frequency component; these effects were rescued by choline administration. Interestingly, the protective effects of choline could be partially reversed by administration of the muscarinic receptor antagonist atropine. This suggests that choline might be a promising adjunct therapeutic agent to alleviate DOX-induced cardiotoxicity.

Cardiomyocyte Atrophy, an Underestimated Contributor in Doxorubicin-Induced Cardiotoxicity

Left ventricular (LV) mass loss is prevalent in doxorubicin (DOX)-induced cardiotoxicity and is responsible for the progressive decline of cardiac function. Comparing with the well-studied role of cell death, the part of cardiomyocyte atrophy (CMA) playing in the LV mass loss is underestimated and the knowledge of the underlying mechanism is still limited. In this review, we summarized the recent advances in the DOX-induced CMA. We found that the CMA caused by DOX is associated with the upregulation of FOXOs and “atrogenes,” the activation of transient receptor potential canonical 3-NADPH oxidase 2 (TRPC3-Nox2) axis, and the suppression of IGF-1-PI3K signaling pathway. The imbalance of anabolic and catabolic process may be the common final pathway of these mechanisms. At last, we provided some strategies that have been demonstrated to alleviate the DOX-induced CMA in animal models.

Nicotinic Acid Riboside Regulates Nrf-2/P62-Related Oxidative Stress and Autophagy to Attenuate Doxorubicin-Induced Cardiomyocyte Injury

Doxorubicin (Dox) is an effective chemotherapeutic drug for the treatment of various cancers. Due to its potential fatal cardiotoxic side effects, the clinical application is often limited. Dexrazoxane (Dex) is the only drug approved by the Food and Drug Administration (FDA) for the prevention of Dox-induced cardiotoxicity but has side effects. Thus, more protective strategies should be explored. If NAD⁺ plays a role in maintaining heart function, its precursor prospectively alleviates Dox-induced cellular injury. Here, we studied the protective effects of nicotinic acid riboside (NAR) on Dox-induced cardiotoxicity in vivo and in vitro. We found that NAR significantly improved the cardiac function of Dox-treated mice by restoring ejection fraction (EF), fractional shortening (FS), and serum level of cardiac troponin (cTnI). NAR not only reduced malondialdehyde (MDA), lactate dehydrogenase (LDH), and reactive oxygen species (ROS) levels in Dox-treated cardiomyocytes but also further promoted the activities of cardiac superoxide dismutase (SOD) and glutathione (GSH). Following exposure to 5 μM Dox, cotreatment with NAR exhibited increased cell viability with a decrease in the apoptosis cell population. Moreover, the levels of apoptosis-related proteins, as well as proteins involved in oxidative stress and autophagy, were altered after NAR treatment. Collectively, these findings underline the protective potential of NAR against Dox-induced cardiomyocyte injury by regulating Nrf-2/P62-related oxidative stress and autophagy, which could potentially promote survival.

Protective effects of necrostatin-1 on doxorubicin-induced cardiotoxicity in rat heart

Background: Doxorubicin (Dox) is one of the most effective antineoplastic drugs which has severe cardiotoxic effects, limiting its clinical usage. Though the exact mechanism of doxorubicin-induced cardiotoxicity is yet to be elucidated, it is shown that production of reactive oxygen species (ROS) increases oxidative stress and leads to cardiomyocyte apoptosis and necroptosis which is also defined as a programmed cell death.Purpose: In the present study, we investigate the effects of necrostatin-1 (Nec-1)-an inhibitor of receptor interaction proteins 1 (RIP1) and necroptosis-on doxorubicin-induced cardiotoxicity in rats.Research Design: Hearts were isolated and perfused by the Langendorff system in all four groups. Perfusion pressure (PP), left ventricular developed pressure (LVDP) and heart rate per minute (HR), LV (dP/dt) max, and LV (dP/dt) min which shows cardiac contractility and relaxation were recorded.Results: Results showed that PP significantly increased with Dox treatment and significantly decreased with Nec-1 treatment, while HR, LVDP, LV (dP/dt) max, and LV (dP/dt) min values significantly decreased with the Dox-treated group and significantly increased with Nec-1 treatment. Also with Nec-1 treatment, gene expression levels of anti-apoptotic Bcl-2 significantly increased and pro-apoptotic protein Bax, apoptotic marker caspase-3, and Nox-2 significantly decreased compared to the Dox-treated group. In heart tissues, MDA levels were significantly increased with Dox and decreased with Nec-1 treatment. These results were supported by the histological analysis indicated that Nec-1 reduced doxorubicin-induced cellular injury.Conclusions: In conclusion, our data indicate that Nec-1 ameliorates doxorubicin-induced cardiotoxicity by reducing oxidative stress injury and attenuating apoptosis and necroptosis.

SIRT4 Suppresses Doxorubicin-Induced Cardiotoxicity by Regulating the AKT/mTOR/Autophagy Pathway

Doxorubicin (DOX) is a potent anthracycline chemotherapeutic drug. DOX-induced cardiotoxicity (DIC) limits its application in cancer treatment, as this complication is detrimental and fatal. Reactive oxygen species (ROS) production, autophagic dysfunction and cell death are crucial factors related to DIC. Previous studies have shown that SIRT4 is associated with cardiac energy metabolism, cardiac mitochondrial dysfunction and cardiac cell death, but it is unclear whether SIRT4 affects DOX-induced cardiac injury. Our data suggested that SIRT4 overexpression in vivo and in vitro could alleviate DIC by improving cardiac function and reducing cardiomyocyte apoptosis and autophagy. However, autophagy activation by rapamycin abolished the protective effect of SIRT4 overexpression on DIC. Furthermore, in the context of DOX treatment, SIRT4 overexpression activated the Akt/mTOR signaling pathway and inhibited autophagy through the Akt/mTOR signaling pathway. Our findings indicate that SIRT4 overexpression protects against DIC by inhibiting Akt/mTOR-dependent autophagy. These findings may provide a prospective therapeutic target for DIC.

Serum Metabolomic Profiling Reveals Biomarkers for Early Detection and Prognosis of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most common aggressive malignancies worldwide, particularly in northern China. The absence of specific early symptoms and biomarkers leads to late-stage diagnosis, while early diagnosis and risk stratification are crucial for improving overall prognosis. We performed UPLC-MS/MS on 450 ESCC patients and 588 controls consisting of a discovery group and two validation groups to identify biomarkers for early detection and prognosis. Bioinformatics and clinical statistical methods were used for profiling metabolites and evaluating potential biomarkers. A total of 105 differential metabolites were identified as reliable biomarker candidates for ESCC with the same tendency in three cohorts, mainly including amino acids and fatty acyls. A predictive model of 15 metabolites [all-trans-13,14-dihydroretinol, (±)-myristylcarnitine, (2S,3S)-3-methylphenylalanine, 3-(pyrazol-1-yl)-L-alanine, carnitine C10:1, carnitine C10:1 isomer1, carnitine C14-OH, carnitine C16:2-OH, carnitine C9:1, formononetin, hyodeoxycholic acid, indole-3-carboxylic acid, PysoPE 20:3, PysoPE 20:3(2n isomer1), and resolvin E1] was developed by logistic regression after LASSO and random forest analysis. This model held high predictive accuracies on distinguishing ESCC from controls in the discovery and validation groups (accuracies > 89%). In addition, the levels of four downregulated metabolites [hyodeoxycholic acid, (2S,3S)-3-methylphenylalanine, carnitine C9:1, and indole-3-carboxylic acid] were significantly higher in early cancer than advanced cancer. Furthermore, three independent prognostic markers were identified by multivariate Cox regression analyses with and without clinical indicators: a high level of MG(20:4)isomer and low levels of 9,12-octadecadienoic acid and L-isoleucine correlated with an unfavorable prognosis; the risk score based on these three metabolites was able to stratify patients into low or high risk. Moreover, pathway analysis indicated that retinol metabolism and linoleic acid metabolism were prominent perturbed pathways in ESCC. In conclusion, metabolic profiling revealed that perturbed amino acids and lipid metabolism were crucial metabolic signatures of ESCC. Both panels of diagnostic and prognostic markers showed excellent predictive performances. Targeting retinol and linoleic acid metabolism pathways may be new promising mechanism-based therapeutic approaches. Thus, this study would provide novel insights for the early detection and risk stratification for the clinical management of ESCC and potentially improve the outcomes of ESCC.

Resolvin D1 Attenuates Doxorubicin-Induced Cardiotoxicity by Inhibiting Inflammation, Oxidative and Endoplasmic Reticulum Stress

Resolvin D1 (RvD1) is a lipid mediator that promotes resolution of inflammation. However, the function of RvD1 in doxorubicin- (Dox-) induced cardiotoxicity remains to be clarified. This study aimed to investigate whether RvD1 could attenuate Dox-induced cardiac injury. The mice were divided into three groups: control, Dox (20 mg/kg, once, intraperitoneally), and Dox + RvD1. RvD1 (2.5 μg/kg, intraperitoneally) was injected daily for 5 days. Echocardiography was performed to evaluate the cardiac function, and the heart tissue and serum samples were collected for further analyses. The results showed that RvD1 attenuated the decreased ratio of heart weight/body weight and heart weight/tibia length, the increased level of creatine kinase and activity of lactate dehydrogenase after Dox treatment. RvD1 improved the ejection fraction and fractional shortening of left ventricular and attenuated the severity of apoptosis induced by Dox. As for the underlying pathways, the results showed that RvD1 reduced the expression of IL-1 and IL-6, and attenuated the phosphorylation of P65 in cardiac tissue. RvD1 attenuated the oxidative stress induced by Dox, as demonstrated by the attenuated levels of superoxide dismutase, glutathione, and malondialdehyde, decreased expression of Nox-2 and Nox-4 and increased expression of Nrf-2 and HO-1. In addition, RvD1 also inhibited the endoplasmic reticulum stress induced by Dox. These results indicate the potential therapeutic benefits of RvD1 in Dox-induced cardiotoxicity in mice, and the mechanism may be related to the attenuated inflammation, oxidative stress and endoplasmic reticulum stress.

The therapeutic effect of hesperetin on doxorubicin-induced testicular toxicity: Potential roles of the mechanistic target of rapamycin kinase (mTOR) and dynamin-related protein 1 (DRP1)

Clinical utilization of doxorubicin (DOX), which is a commonly used chemotherapeutic, is restricted due to toxic effects on various tissues. Using hesperetin (HST), an antioxidant used in Chinese traditional medicine protects testis against DOX-induced toxicity although the molecular mechanisms are not well-known. The study was aimed to examine the possible role of the mechanistic target of rapamycin kinase (mTOR) and dynamin 1-like dynamin-related protein 1 (DRP1) in the therapeutic effects of HST on the DOX-induced testicular toxicity. Rats were divided into Control, DOX, DOX + HST, and HST groups (n = 7). Single-dose DOX (15 mg/kg) was administered intraperitoneally and HST (50 mg/kg) was administered by oral gavage every other day for 28 days. Total antioxidant status (TAS), histopathological evaluations, immunohistochemistry, and gene expression level detection analyses were performed. Histopathologically, DOX-induced testicular damage was ameliorated by HST treatment. DOX reduced testicular TAS levels and increased oxidative stress markers, 8-Hydroxy-deoxyguanosine (8-OHdG), and 4-Hydroxynonenal (4-HNE). Also, upregulated mTOR and DRP1 expressions with DOX exposure were decreased after HST treatment in the testis (p < 0.05). On the other hand, DOX-administration downregulated miR-150-5p and miR-181b-2-3p miRNAs, targeting mTOR and mRNA levels of beclin 1 (BECN1) and autophagy-related 5 (ATG5), autophagic markers. Furthermore, these levels were nearly similar to control testis samples in the DOX + HST group (p < 0.05). The study demonstrated that HST may have a therapeutic effect on DOX-induced testicular toxicity by removing reactive oxygen species (ROS) and by modulating the mTOR and DRP1 expressions, which have a critical role in regulating the balance of generation/elimination of ROS.

Improvement of stability and in vivo antioxidant effect of human glutathione peroxidase mutant by PEGylation

Human glutathione peroxidase (GPx), as an important kind of antioxidant enzyme, is often used for the removal of reactive oxygen species. Unfortunately, the application has been hindered by its limited source and poor stability. To solve these problems, human glutathione peroxidase mutant (GPxM) with high activity and yield was obtained using Escherichia coli BL21(DE3) cys auxotrophic strain and the single-protein production system in our previous work. However, the antioxidant effect of this novel recombinant protein drug in animals has not been demonstrated, and its immunogenicity and short biological half-life as a biological macromolecule may have seriously hindered its clinical application. Therefore, it is important to find an effective strategy to address the above issues. In this work, PEGylated GPxM was prepared by conjugating the corresponding mutant with monomethoxy polyethylene glycol succinimidyl succinate (SS-mPEG). We researched the structure, stability, pharmacokinetic properties, antioxidant effect in vivo and protective mechanism against adriamycin (ADR)-mediated cardiotoxicity of modified products, and compared with the above properties of GPxM. The results revealed that GPxM had an excellent antioxidant effect in vivo, and PEGylation can enhance the stability, half-life and antioxidant effect of GPxM while reducing immunogenicity. In addition, the above improvement of PEGylated GPx1M was stronger than that of monoPEGylated GPx4M. Hence, PEGylation might be an effective method to broaden the applications of GPxM as the important antioxidant drug, especially the PEGylated GPx1M with high antioxidant effect.

Resolution of inflammation: An organizing principle in biology and medicine

The resolution of inflammation has emerged as a critical endogenous process that protects host tissues from prolonged or excessive inflammation that can become chronic. Failure of the resolution of inflammation is a key pathological mechanism that drives the progression of numerous inflammation-driven diseases. Essential polyunsaturated fatty acid (PUFA)-derived autacoid mediators termed 'specialized pro-resolving mediators' (SPMs) regulate endogenous resolution programs by limiting further neutrophil tissue infiltration and stimulating local immune cell (e.g., macrophage)-mediated clearance of apoptotic polymorphonuclear neutrophils, cellular debris, and microbes, as well as counter-regulating eicosanoid/cytokine production. The SPM superfamily encompasses lipoxins, resolvins, protectins, and maresins. Our understanding of the resolution phase of acute inflammation has grown exponentially in the past three decades with the discovery of novel pro-resolving lipid mediators, their pro-efferocytosis mechanisms, and their receptors. Technological advancement has further facilitated lipid mediator metabolipidomic based profiling of healthy and diseased human tissues, highlighting the extraordinary therapeutic potential of SPMs across a broad array of inflammatory diseases including cancer. As current front-line cancer therapies such as surgery, chemotherapy, and radiation may induce various unwanted side effects such as robust pro-inflammatory and pro-tumorigenic host responses, characterizing SPMs and their receptors as novel therapeutic targets may have important implications as a new direction for host-targeted cancer therapy. Here, we discuss the origins of inflammation resolution, key discoveries and the failure of resolution mechanisms in diseases with an emphasis on cancer, and future directions focused on novel therapeutic applications for this exciting and rapidly expanding field.

Nerolidol Attenuates Oxidative Stress, Inflammation, and Apoptosis by Modulating Nrf2/MAPK Signaling Pathways in Doxorubicin-Induced Acute Cardiotoxicity in Rats

The clinical usage of doxorubicin (DOX), a potent anthracycline antineoplastic drug, is often limited by its cardiotoxic effects. Thus, for improving usage of DOX, the aim of this study was to assess the cardioprotective effects of nerolidol (NERO) in a rat model of DOX-induced acute cardiotoxicity and examine underlying molecular mechanisms that contribute to these effects. To induce acute cardiotoxicity male albino Wistar rats were injected with single dose intraperitoneal DOX (12.5 mg/kg). The rats were treated with NERO (50 mg/kg, orally) for five days. DOX-injected rats showed elevated levels of cardiac marker enzymes and enhanced oxidative stress markers along with altered Nrf2/Keap1/HO-1 signaling pathways. DOX administration also induced the activation of NF-κB/MAPK signaling and increased the levels and expression of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) as well as expression of inflammatory mediators (iNOS and COX-2) in the heart. DOX also triggered DNA damage and apoptotic cell death in the myocardium. Additionally, histological studies revealed structural alterations of the myocardium. NERO treatment exhibited protection against the deleterious results of DOX on myocardium, as evidenced by the restoration of altered biochemical parameters, mitigated oxidative stress, inflammation, and apoptosis. The findings of the present study demonstrate that NERO provides cardioprotective effects against DOX-induced acute cardiotoxicity attributed to its potent antioxidant, anti-inflammatory, and antiapoptotic activities through modulating cellular signaling pathways.

Astragaloside IV Attenuates the Myocardial Injury Caused by Adriamycin by Inhibiting Autophagy

Astragaloside IV (ASIV) is the main active component of Astragalus, and can ameliorate cardiomyocyte hypertrophy, apoptosis and fibrosis. In this experiment, we studied how ASIV reduces the cardiotoxicity caused by adriamycin and protects the heart. To this end, rats were randomly divided into the control, ADR, ADR + ASIV and ASIV groups (n = 6). Echocardiography was used to observe cardiac function, HE staining was used to observe myocardial injury, TUNEL staining was used to observe myocardial cell apoptosis, and immunofluorescence and Western blotting was used to observe relevant proteins expression. Experiments have shown that adriamycin can damage heart function in rats, and increase the cell apoptosis index, autophagy level and oxidative stress level. Further results showed that ADR can inhibit the PI3K/Akt pathway. ASIV treatment can significantly improve the cardiac function of rats treated with ADR and regulate autophagy, oxidative stress and apoptosis. Our findings indicate that ASIV may reduce the heart damage caused by adriamycin by activating the PI3K/Akt pathway.

Protective Effects of Oroxylin A against Doxorubicin-Induced Cardiotoxicity via the Activation of Sirt1 in Mice

Doxorubicin- (DOX-) related cardiac injury impairs the life quality of patients with cancer. This largely limited the clinical use of DOX. It is of great significance to find a novel strategy to reduce DOX-related cardiac injury. Oroxylin A (OA) has been identified to exert beneficial effects against inflammatory diseases and cancers. Here, we investigated whether OA could attenuate DOX-induced acute cardiotoxicity in mice. A single dose of DOX was used to induce acute cardiac injury in mice. To explore the protective effects, OA was administered to mice for ten days beginning from five days before DOX injection. The data in our study indicated that OA inhibited DOX-induced heart weight loss, reduction in cardiac function, and the elevation in myocardial injury markers. DOX injection resulted in increased oxidative damage, inflammation accumulation, and myocardial apoptosis in vivo and in vitro, and these pathological alterations were alleviated by treatment of OA. OA activated the sirtuin 1 (Sirt1) signaling pathway via the cAMP/protein kinase A, and its protective effects were blocked by Sirt1 deficiency. OA treatment did not affect the tumor-killing action of DOX in tumor-bearing mice. In conclusion, OA protected against DOX-related acute cardiac injury via the regulation of Sirt1.

Roles of Specialized Pro-Resolving Lipid Mediators in Autophagy and Inflammation

Autophagy is a catabolic pathway that accounts for degradation and recycling of cellular components to extend cell survival under stress conditions. In addition to this prominent role, recent evidence indicates that autophagy is crucially involved in the regulation of the inflammatory response, a tightly controlled process aimed at clearing the inflammatory stimulus and restoring tissue homeostasis. To be efficient and beneficial to the host, inflammation should be controlled by a resolution program, since uncontrolled inflammation is the underlying cause of many pathologies. Resolution of inflammation is an active process mediated by a variety of mediators, including the so-called specialized pro-resolving lipid mediators (SPMs), a family of endogenous lipid autacoids known to regulate leukocyte infiltration and activities, and counterbalance cytokine production. Recently, regulation of autophagic mechanisms by these mediators has emerged, uncovering unappreciated connections between inflammation resolution and autophagy. Here, we summarize mechanisms of autophagy and resolution, focusing on the contribution of autophagy in sustaining paradigmatic examples of chronic inflammatory disorders. Then, we discuss the evidence that SPMs can restore dysregulated autophagy, hypothesizing that resolution of inflammation could represent an innovative approach to modulate autophagy and its impact on the inflammatory response.