Glabridin Prevents Doxorubicin-Induced Cardiotoxicity Through Gut Microbiota Modulation and Colonic Macrophage Polarization in Mice

A longitudinal evaluation of oxidative stress - mitochondrial dysfunction - ferroptosis genes in anthracycline-induced cardiotoxicity

BACKGROUND

Antineoplastic medications, including doxorubicin, idarubicin, and epirubicin, have been found to adversely affect the heart due to oxidative stress - mitochondrial dysfunction - ferroptosis (ORMFs), which act as contributing attributes to anthracycline-induced cardiotoxicity. To better understand this phenomenon, the time-resolved measurements of ORMFS genes were analyzed in this study.

METHODS

The effect of three anthracycline drugs on ORMFs genes was studied using a human 3D cardiac microtissue cell model. Transcriptome data was collected over 14 days at two doses (therapeutic and toxic). WGCNA identified key module-related genes, and functional enrichment analysis investigated the biological processes quantified by ssGSEA, such as immune cell infiltration and angiogenesis. Biopsies were collected from heart failure patients and control subjects. GSE59672 and GSE2965 were collected for validation. Molecular docking was used to identify anthracyclines's interaction with key genes.

RESULTS

The ORMFs genes were screened in vivo or in vitro. Using WGCNA, six co-expressed gene modules were grouped, with MEblue emerging as the most significant module. Eight key genes intersecting the blue module with the dynamic response genes were obtained: CD36, CDH5, CHI3L1, HBA2, HSD11B1, OGN, RPL8, and VWF. Compared with control samples, all key genes except RPL8 were down-regulated in vitro ANT treatment settings, and their expression levels varied over time. According to functional analyses, the key module-related genes were engaged in angiogenesis and the immune system pathways. In all ANT-treated settings, ssGSEA demonstrated a significant down-regulation of angiogenesis score and immune cell activity, including Activated CD4 T cell, Immature B cell, Memory B cell, Natural killer cell, Type 1 T helper cell, and Type 2 T helper cell. Molecular docking revealed that RPL8 and CHI3L1 show significant binding affinity for anthracyclines.

CONCLUSION

This study focuses on the dynamic characteristics of ORMFs genes in both human cardiac microtissues and cardiac biopsies from ANT-treated patients. It has been highlighted that ORMFs genes may contribute to immune infiltration and angiogenesis in cases of anthracycline-induced cardiotoxicity. A thorough understanding of these genes could potentially lead to improved diagnosis and treatment of the disease.

Possible pathogenic mechanisms for doxorubicin-induced splenic atrophy in a human breast cancer xenograft mouse model

Doxorubicin-based chemotherapy is a widely used first-line treatment for breast cancer, yet it is associated with various side effects, including splenic atrophy. However, the pathogenic mechanisms underlying doxorubicin-induced atrophy of the spleen remain unclear. This study investigates that doxorubicin treatment leads to splenic atrophy through several interconnected pathways involving histological changes, an inflammatory response, and apoptosis. Immunohistochemical and western blot analyses revealed reduced size of white and red pulp, decreased cellularity, amyloidosis, and fibrotic remodeling in the spleen following doxorubicin treatment. Additionally, increased secretion of pro-inflammatory cytokines was detected using an antibody array and enzyme-linked immunosorbent assay (ELISA), which triggers inflammation through the regulation of signal transducer and activator of transcription 3 (STAT3) and nuclear factor-kappa B (NF-κB) signaling pathways. Further analysis revealed that the loss of regulators and effectors of the oxidative defense system, including sirtuin (Sirt)3, Sirt5, superoxide dismutase (SOD)1, and SOD2, was implicated in the upstream regulation of caspase-dependent cellular apoptosis. These findings provide insights on the pathogenic mechanisms underlying doxorubicin-induced splenic atrophy and suggest that further investigation may be warranted to explore strategies for managing potential side effects in breast cancer patients treated with doxorubicin.

Minimally invasive vagus nerve stimulation modulates mast cell degranulation via the microbiota-gut-brain axis to ameliorate blood-brain barrier and intestinal barrier damage following ischemic stroke

Mast cells (MCs) play a significant role in various diseases, and their activation and degranulation can trigger inflammatory responses and barrier damage. Several studies have indicated that vagus nerve stimulation (VNS) exerts ameliorates neurological injury, and regulates gut MC degranulation. However, there is limited research on the modulatory effect of VNS on MCs in both the gut and brain in brain ischemia-reperfusion (I/R) injury in this process. We aim to develop a minimally invasive, targeted and convenient VNS approach to assess the impact of VNS and to clarify the relationship between VNS and MCs on the prognosis of acute ischemic stroke. We utilized middle cerebral artery occlusion/reperfusion (MCAO/r) to induce brain I/R injury. After the experiment, the motor function and neurofunctional impairments of the rats were detected, and the gastrointestinal function, blood-brain barrier (BBB) and intestinal barrier damage, and systemic and local inflammation were evaluated by Nissl, TTC staining, Evans blue, immunofluorescence staining, transmission electron microscopy, western blot assays, ELISA, and fecal 16S rRNA sequencing methods. Our research confirmed that our minimally invasive VNS method is a novel approach for stimulating the vagus nerve. VNS alleviated motor deficits and gastrointestinal dysfunction while also suppressing intestinal and neuroinflammation. Additionally, VNS ameliorated gut microbiota dysbiosis in rats. Furthermore, our analysis indicated that VNS reduces chymase secretion by modulating MCs degranulation and improves intestinal and BBB damage. Our results showed that VNS treatment can alleviate the damage of BBB and colonic barrier after cerebral I/R by modulating mast cell degranulation, and alleviates systemic inflammatory responses.

Role of gut microbiota in doxorubicin-induced cardiotoxicity: from pathogenesis to related interventions

Doxorubicin (DOX) is a broad-spectrum and highly efficient anticancer agent, but its clinical implication is limited by lethal cardiotoxicity. Growing evidences have shown that alterations in intestinal microbial composition and function, namely dysbiosis, are closely linked to the progression of DOX-induced cardiotoxicity (DIC) through regulating the gut-microbiota-heart (GMH) axis. The role of gut microbiota and its metabolites in DIC, however, is largely unelucidated. Our review will focus on the potential mechanism between gut microbiota dysbiosis and DIC, so as to provide novel insights into the pathophysiology of DIC. Furthermore, we summarize the underlying interventions of microbial-targeted therapeutics in DIC, encompassing dietary interventions, fecal microbiota transplantation (FMT), probiotics, antibiotics, and natural phytochemicals. Given the emergence of microbial investigation in DIC, finally we aim to point out a novel direction for future research and clinical intervention of DIC, which may be helpful for the DIC patients.

Changes in Intestinal Flora and Serum Metabolites Pre- and Post-Antitumor Drug Therapy in Patients with Non-Small Cell Lung Cancer

OBJECTIVE

this study aimed to identify the relationships between gut microbiota, metabolism, and non-small cell lung cancer (NSCLC) treatment outcomes, which are presently unclear.

METHODS

in this single-center prospective cohort study, we investigated changes in the gut microbiota and serum metabolite profile in 60 patients with NSCLC after four cycles of anticancer therapy.

RESULTS

The microbial landscape of the gut exhibited a surge in Proteobacteria and Verrucomicrobiota populations, alongside a decline in Firmicutes, Actinobacteriota, and Bacteroidota. Furthermore, a significant shift in the prevalence of certain bacterial genera was noted, with an increase in Escherichia/Shigella and Klebsiella, contrasted by a reduction in Bifidobacterium. Metabolomic analysis uncovered significant changes in lipid abundances, with certain metabolic pathways markedly altered post-treatment. Correlation assessments identified strong links between certain gut microbial genera and serum metabolite concentrations. Despite these findings, a subgroup analysis delineating patient responses to therapy revealed no significant shifts in the gut microbiome's composition after four cycles of treatment.

CONCLUSIONS

This study emphasizes the critical role of gut microbiota changes in NSCLC patients during anticancer treatment. These insights pave the way for managing treatment complications and inform future research to improve patient care by understanding and addressing these microbiota changes.

Fibre-rich diet attenuates chemotherapy-related neuroinflammation in mice

The gastrointestinal microbiota has received increasing recognition as a key mediator of neurological conditions with neuroinflammatory features, through its production of the bioactive metabolites, short-chain fatty acids (SCFAs). Although neuroinflammation is a hallmark shared by the neuropsychological complications of chemotherapy (including cognitive impairment, fatigue and depression), the use of microbial-based therapeutics has not previously been studied in this setting. Therefore, we aimed to investigate the effect of a high fibre diet known to modulate the microbiota, and its associated metabolome, on neuroinflammation caused by the common chemotherapeutic agent 5-fluorouracil (5-FU). Twenty-four female C57Bl/6 mice were treated with 5-FU (400 mg/kg, intraperitoneal, i.p.) or vehicle control, with or without a high fibre diet (constituting amylose starch; 4.7 % crude fibre content), given one week prior to 5-FU and until study completion (16 days after 5-FU). Faecal pellets were collected longitudinally for 16S rRNA gene sequencing and terminal SCFA concentrations of the caecal contents were quantified using gas chromatography-mass spectrometry (GC-MS). Neuroinflammation was determined by immunofluorescent analysis of astrocyte density (GFAP). The high fibre diet significantly altered gut microbiota composition, increasing the abundance of Bacteroidaceae and Akkermansiaceae (p < 0.0001 and p = 0.0179) whilst increasing the production of propionate (p = 0.0097). In the context of 5-FU, the diet reduced GFAP expression in the CA1 region of the hippocampus (p < 0.0001) as well as the midbrain (p = 0.0216). Astrocyte density negatively correlated with propionate concentrations and the abundance of Bacteroidaceae and Akkermansiaceae, suggesting a relationship between neuroinflammatory and gastrointestinal markers in this model. This study provides the first evidence of the neuroprotective effects of fibre via dietary intake in alleviating the neuroimmune changes seen in response to systemically administered 5-FU, indicating that the microbiota-gut-brain axis is a targetable mediator to reduce the neurotoxic effects of chemotherapy treatment.

The Therapeutic Role and Mechanism of Glabridin Under Aspergillus fumigatus Infection

Purpose: To characterize the efficiency of glabridin alone and in combination with clinical antifungals in Aspergillus fumigatus keratitis. Methods: The broth microdilution method was performed to investigate whether glabridin exerted an antifungal role on planktonic cells and immature and mature biofilm. Antifungal mechanism was evaluated by Sorbitol and Ergosterol Assays. The synergistic effect of glabridin and antifungals was assessed through the checkerboard microdilution method and time-killing test. Regarding anti-inflammatory role, inflammatory substances induced by A. fumigatus were assessed by real-time quantitative polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay. Drug toxicity was assessed by Draize test in vivo. Macrophage phenotypes were examined by flow cytometry. Results: Regarding antifungal activity, glabridin destroyed fungal cell wall and membrane on planktonic cells and suppressed immature and mature biofilm formation. After combining with natamycin or amphotericin B, glabridin possessed a potent synergistic effect against A. fumigatus. Regarding anti-inflammatory aspects, Dectin-1, toll‑like receptor (TLR)-2 and TLR-4 expression of human corneal epithelial cells were significantly elevated after A. fumigatus challenge and reduced by glabridin. The elevated expression of interleukin-1β and tumor necrosis factor-alpha induced by A. fumigatus or corresponding agonists were reversed by glabridin, equivalent to the effect of corresponding inhibitors. Glabridin could also contribute to anti-inflammation by downregulating inflammatory mediator expression to suppress macrophage infiltration. Conclusions: Glabridin contributed to fungal clearance by destroying fungal cell wall and membrane, and disrupting biofilm. Combining glabridin with clinical antifungals was superior in reducing A. fumigatus growth. Glabridin exerted an anti-inflammatory effect by downregulating proinflammatory substance expression and inhibiting macrophage infiltration, which provide a potential agent and treatment strategies for fungal keratitis.

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

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

The Nutritional Intervention of Ingredients from Food Medicine Homology Regulating Macrophage Polarization on Atherosclerosis

The polarization of macrophages plays a crucial regulatory role in a range of physiological and pathological processes involving macrophages. There are numerous concerns with macrophage polarization in atherosclerosis; however, most focus on modulating macrophage polarization to improve the microenvironment, and the mechanism of action remains unknown. In recent years, the advantages of natural and low-toxicity side effects of food medicine homology-derived substances have been widely explored. Few reports have started from ingredients from food medicine homology to regulate the polarization of macrophages so that early intervention can reduce or delay the process of atherosclerosis. This review summarizes the classification of macrophage polarization and related markers in the process of atherosclerosis. It summarizes the regulatory role of ingredients from food medicine homology in macrophage polarization and their possible mechanisms to provide ideas and inspiration for the nutritional intervention in vascular health.

Immunomodulatory effect of glabridin in ovalbumin induced allergic asthma and its comparison with methylprednisolone in a preclinical rodent model

Glabridin, a polyphenolic flavonoid derived from Glycyrrhiza glabra (licorice) roots, has shown anti-inflammatory and antioxidant properties. The current study sought to investigate glabridin's immunomodulatory effect in ovalbumin induced allergic asthma. Healthy male Wistar rats were divided into five groups. Group I served as a control group. Asthma was induced in groups II- IV. Groups III and IV were treated with glabridin (40 mg/kg) and methylprednisolone (15 mg/kg), respectively. Inflammatory cells counts were determined in blood and bronchoalveolar lavage fluid (BALF). Serum IgE levels and levels of catalase, superoxide dismutase and glutathione peroxidase in lung homogenate were measured. The levels of mRNA expression of pro-inflammatory, anti-inflammatory and oxidative stress markers were analysed. Delayed type hypersensitivity (DTH) and acute toxicity of glabridin were also checked. Glabridin significantly decreased inflammatory cells in the blood and BALF. It increased the concentration of antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase. Glabridin markedly decreased serum IgE levels and DTH when compared to asthmatic rats. It significantly alleviated the expression of TNF-α, IL-4, IL-5, CXCL1, iNOS, and NF-κB. Administering 10 times the therapeutic dose of glabridin did not show any signs of acute toxicity. Findings suggest that glabridin has the potential to ameliorate allergic asthma and its effects are comparable to those of methylprednisolone. The immunomodulatory effect of glabridin might be contributed by the suppression of pro-inflammatory cytokines, oxidative stress markers, IgE antibodies, and elevation of antioxidant enzymes, suggesting future study and clinical trials to propose it as a candidate to treat allergic asthma.

The impact of microbiota-derived short-chain fatty acids on macrophage activities in disease: Mechanisms and therapeutic potentials

Short-chain fatty acids (SCFAs) derived from the fermentation of carbohydrates by gut microbiota play a crucial role in regulating host physiology. Among them, acetate, propionate, and butyrate are key players in various biological processes. Recent research has revealed their significant functions in immune and inflammatory responses. For instance, butyrate reduces the development of interferon-gamma (IFN-γ) generating cells while promoting the development of regulatory T (Treg) cells. Propionate inhibits the initiation of a Th2 immune response by dendritic cells (DCs). Notably, SCFAs have an inhibitory impact on the polarization of M2 macrophages, emphasizing their immunomodulatory properties and potential for therapeutics. In animal models of asthma, both butyrate and propionate suppress the M2 polarization pathway, thus reducing allergic airway inflammation. Moreover, dysbiosis of gut microbiota leading to altered SCFA production has been implicated in prostate cancer progression. SCFAs trigger autophagy in cancer cells and promote M2 polarization in macrophages, accelerating tumor advancement. Manipulating microbiota- producing SCFAs holds promise for cancer treatment. Additionally, SCFAs enhance the expression of hypoxia-inducible factor 1 (HIF-1) by blocking histone deacetylase, resulting in increased production of antibacterial effectors and improved macrophage-mediated elimination of microorganisms. This highlights the antimicrobial potential of SCFAs and their role in host defense mechanisms. This comprehensive review provides an in-depth analysis of the latest research on the functional aspects and underlying mechanisms of SCFAs in relation to macrophage activities in a wide range of diseases, including infectious diseases and cancers. By elucidating the intricate interplay between SCFAs and macrophage functions, this review aims to contribute to the understanding of their therapeutic potential and pave the way for future interventions targeting SCFAs in disease management.

Glabridin Inhibits Aspergillus fumigatus Growth and Alleviate Inflammation Mediated by Dectin-2 and NLRP3 Inflammasome

PURPOSE

The research was used to uncover the mechanism of glabridin in Aspergillus fumigatus keratitis in anti-fungus and anti-inflammation.

METHODS

In vitro, RAW 264.7 cells were infected with A. fumigatus with incubation of glabridin in different concentrations. Real-time quantitative polymerase chain reaction (RT‑qPCR), Western blot, and enzyme-linked immunosorbent assay (ELISA) were used to assess the inflammatory severe and alternation with the intervention of Dectin-2 siRNA and glabridin. In vivo, A. fumigatus keratitis mouse models were established by spore intra-stromal injection and treated with glabridin or PBS. And disease scores, inflammatory mediators, and periodic acid-schiff (PAS) staining were exhibited to demonstrate the therapeutic efficiency of glabridin in vivo. Morphological interference assay monitored fungal germination. Scanning and transmission electron microscopy were used to observe the growth of fungi.

RESULTS

In RAW 264.7 cells and mouse keratitis models, noncytotoxic 16 μg/mL glabridin showed significant inhibition in the expression of Dectin-2, NLRP3, Caspase-1, IL-1β, and TNF-α after A. fumigatus infection, almost similar to the intervention of Dectin-2 siRNA. PAS staining illustrated the reduced hyphal distribution in cornea stroma with glabridin treatment. Glabridin remarkably inhibited A. fumigatus growth through delaying germination and disrupting the integrity of the hyphae membrane.

CONCLUSION

Glabridin plays an anti-inflammatory role in A. fumigatus challenge via suppression of the Dectin-2 and NLRP3 inflammasome, and plays an anti-fungal role through delaying germination and changing the hyphal integrity.KEY MESSAGESGlabridin plays an anti-inflammatory role in A. fumigatus infection of RAW264.7 cells in a concentration-dependent manner and through Dectin-2 mediation.Glabridin decreases fungal distribution and inflammation in mouse A. fumigatus keratitis.Glabridin inhibits A. fumigatus growth by delaying germination and disrupting cellular structure in vitro.

Review on the Diverse Biological Effects of Glabridin

Glabridin is a prenylated isoflavan from the roots of Glycyrrhiza glabra Linne and has posed great impact on the areas of drug development and medicine, due to various biological properties such as anti-inflammation, anti-oxidation, anti-tumor, anti-microorganism, bone protection, cardiovascular protection, neuroprotection, hepatoprotection, anti-obesity, and anti-diabetes. Many signaling pathways, including NF-κB, MAPK, Wnt/β-catenin, ERα/SRC-1, PI3K/AKT, and AMPK, have been implicated in the regulatory activities of glabridin. Interestingly, glabridin has been considered as an inhibitor of tyrosinase, P-glycoprotein (P-gp), and CYP2E1 and an activator of peroxisome proliferator-activated receptor γ (PPARγ), although their molecular regulating mechanisms still need further investigation. However, poor water solubility and low bioavailability have greatly limited the clinical applications of glabridin. Hopefully, several effective strategies, such as nanoemulsions, microneedles, and smartPearls formulation, have been developed for improvement.

The Innate Immune System in Cardiovascular Diseases and Its Role in Doxorubicin-Induced Cardiotoxicity

Innate immune cells are the early responders to infection and tissue damage. They play a critical role in the initiation and resolution of inflammation in response to insult as well as tissue repair. Following ischemic or non-ischemic cardiac injury, a strong inflammatory response plays a critical role in the removal of cell debris and tissue remodeling. However, persistent inflammation could be detrimental to the heart. Studies suggest that cardiac inflammation and tissue repair needs to be tightly regulated such that the timely resolution of the inflammation may prevent adverse cardiac damage. This involves the recognition of damage; activation and release of soluble mediators such as cytokines, chemokines, and proteases; and immune cells such as monocytes, macrophages, and neutrophils. This is important in the context of doxorubicin-induced cardiotoxicity as well. Doxorubicin (Dox) is an effective chemotherapy against multiple cancers but at the cost of cardiotoxicity. The innate immune system has emerged as a contributor to exacerbate the disease. In this review, we discuss the current understanding of the role of innate immunity in the pathogenesis of cardiovascular disease and dox-induced cardiotoxicity and provide potential therapeutic targets to alleviate the damage.

Atheroprotective Effects of Glycyrrhiza glabra L

Cardiovascular diseases associated with atherosclerosis are the major cause of death in developed countries. Early prevention and treatment of atherosclerosis are considered to be an important aspect of the therapy of cardiovascular disease. Preparations based on natural products affect the main pathogenetic steps of atherogenesis, and so represent a perspective for the long-term prevention of atherosclerosis development. Numerous experimental and clinical studies have demonstrated the multiple beneficial effects of licorice and its bioactive compounds—anti-inflammatory, anti-cytokine, antioxidant, anti-atherogenic, and anti-platelet action—which allow us to consider licorice as a promising atheroprotective agent. In this review, we summarized the current knowledge on the licorice anti-atherosclerotic mechanisms of action based on the results of experimental studies, including the results of the in vitro study demonstrating licorice effect on the ability of blood serum to reduce intracellular cholesterol accumulation in cultured macrophages, and presented the results of clinical studies confirming the ameliorating activity of licorice in regard to traditional cardiovascular risk factors as well as the direct anti-atherosclerotic effect of licorice.

Impact of the Gastrointestinal Tract Microbiota on Cardiovascular Health and Pathophysiology

ABSTRACT

The microbiota of the gastrointestinal tract (GIT) is an extremely diverse community of microorganisms, and their collective genomes (microbiome) provide a vast arsenal of biological activities, in particular enzymatic ones, which are far from being fully elucidated. The study of the microbiota (and the microbiome) is receiving great interest from the biomedical community as it carries the potential to improve risk-prediction models, refine primary and secondary prevention efforts, and also design more appropriate and personalized therapies, including pharmacological ones. A growing body of evidence, though sometimes impaired by the limited number of subjects involved in the studies, suggests that GIT dysbiosis, i.e. the altered microbial composition, has an important role in causing and/or worsening cardiovascular disease (CVD). Bacterial translocation as well as the alteration of levels of microbe-derived metabolites can thus be important to monitor and modulate, because they may lead to initiation and progression of CVD, as well as to its establishment as chronic state. We hereby aim to provide readers with details on available resources and experimental approaches that are used in this fascinating field of biomedical research, and on some novelties on the impact of GIT microbiota on CVD.

Cardioprotective Effect of Gossypin Against Myocardial Ischemic/Reperfusion in Rats via Alteration of Oxidative Stress, Inflammation and Gut Microbiota

Background

Myocardial ischemic/reperfusion (I/R) injury is a key prognostic factor after the myocardial infarction. However, at the time of reperfusion, the myocardial tissue has undergone for the necrosis and initiated the induction of oxidative stress and inflammation. The current study was to scrutinize the cardioprotective effect of gossypin against ISO-induced I/R injury in myocardial tissue and explore the possible underlying mechanism.

Methods

Sprague Dawley (SD) was used in the current protocol and ISO was used for induction the I/R in rat. The rats were divided into different groups and received the oral administration of gossypin treatment before the reperfusion. The body weight, heart weight and heart body weight ratio were estimated. The antioxidant, cardiac injury parameters, inflammatory cytokines, inflammatory mediators, gut microbiota and lipid parameters were estimated. At the end, heart tissue histopathological study was carried out.

Results

ISO-induced I/R rats received the gossypin treatment significantly (P < 0.001) enhanced the body weight and decreased the heart weight, along with suppressed the infarct size. Gossypin treatment significantly (P < 0.001) reduced the level of heart parameters, such as creatinine kinase-MB (CK-MB), lactate dehydrogenase (LDH), creatine kinase (CK), cardiac troponin I (CTn-I) and cardiac troponin T (CTn-T) in the serum. Gossypin treatment significantly (P < 0.001) altered the cardiac function, hepatic, antioxidant, inflammatory cytokines and inflammatory mediators. Gossypin significantly (P < 0.001) suppressed the MMP-2 and MMP-9 in ISO-induced I/R rats. Gossypin treatment considerably alleviated the gut dysbiosis through altered Firmicutes to Bacteroidetes (F/B) ratio and also maintained the relative abundance of Butyricicoccus, Clostridium IV, Akkermansia, Roseburia and Clostridium XIVs.

Conclusion

Based on result, we can conclude that gossypin is an alternative drug for the treatment of ISO-induced I/R in rats via alteration of oxidative stress, inflammatory reaction and gut microbiota.

Prevotellaceae produces butyrate to alleviate PD-1/PD-L1 inhibitor-related cardiotoxicity via PPARα-CYP4X1 axis in colonic macrophages

BACKGROUND

Immune checkpoint inhibitor-related cardiotoxicity is one of the most lethal adverse effects, and thus, the identification of underlying mechanisms for developing strategies to overcome it has clinical importance. This study aimed to investigate whether microbiota-host interactions contribute to PD-1/PD-L1 inhibitor-related cardiotoxicity.

METHODS

A mouse model of immune checkpoint inhibitor-related cardiotoxicity was constructed by PD-1/PD-L1 inhibitor BMS-1 (5 and 10 mg/kg), and cardiomyocyte apoptosis and cardiotoxicity were determined by hematoxylin and eosin, Masson's trichome and TUNEL assays. 16S rRNA sequencing was used to define the gut microbiota composition. Gut microbiota metabolites short-chain fatty acids (SCFAs) were determined by HPLC. The serum levels of myocardial enzymes (creatine kinase, aspartate transaminase, creatine kinase-MB and lactate dehydrogenase) and the production of M1 factors (TNF-α and IL-1β) were measured by ELISA. The colonic macrophage phenotype was measured by mmunofluorescence and qPCR. The expression of Claudin-1, Occludin, ZO-1 and p-p65 was measured by western blot. The gene expression of peroxisome proliferator-activated receptor α (PPARα) and cytochrome P450 (CYP) 4X1 was determined using qPCR. Statistical analyses were performed using Student's t-test for two-group comparisons, and one-way ANOVA followed by Student-Newman-Keul test for multiple-group comparisons.

RESULTS

We observed intestinal barrier injury and gut microbiota dysbiosis characterized by Prevotellaceae and Rikenellaceae genus depletion and Escherichia-Shigella and Ruminococcaceae genus enrichment, accompanied by low butyrate production and M1-like polarization of colonic macrophages in BMS-1 (5 and 10 mg/kg)-induced cardiotoxicity. Fecal microbiota transplantation mirrored the effect of BMS-1 on cardiomyocyte apoptosis and cardiotoxicity, while macrophage depletion and neutralization of TNF-α and IL-1β greatly attenuated BMS-1-induced cardiotoxicity. Importantly, Prevotella loescheii recolonization and butyrate supplementation alleviated PD-1/PD-L1 inhibitor-related cardiotoxicity. Mechanistically, gut microbiota dysbiosis promoted M1-like polarization of colonic macrophages and the production of proinflammatory factors TNF-α and IL-1β through downregulation of PPARα-CYP4X1 axis.

CONCLUSIONS

Intestinal barrier dysfunction amplifies PD-1/PD-L1 inhibitor-related cardiotoxicity by upregulating proinflammatory factors TNF-α and IL-1β in colonic macrophages via downregulation of butyrate-PPARα-CYP4X1 axis. Thus, targeting gut microbiota to polarize colonic macrophages away from the M1-like phenotype could provide a potential therapeutic strategy for PD-1/PD-L1 inhibitor-related cardiotoxicity.

Desulfovibrio vulgaris, a potent acetic acid-producing bacterium, attenuates nonalcoholic fatty liver disease in mice

The emerging evidence supports the use of prebiotics like herb-derived polysaccharides for treating nonalcoholic fatty liver disease (NAFLD) by modulating gut microbiome. The present study was initiated on the microbiota-dependent anti-NAFLD effect of Astragalus polysaccharides (APS) extracted from Astragalus mongholicus Bunge in high-fat diet (HFD)-fed mice. However, the exact mechanisms underlying the beneficial effects of APS on NAFLD formation remain poorly understood.Co-housing experiment was used to assess the microbiota dependent anti-NAFLD effect of APS. Then, targeted metabolomics and metagenomics were adopted for determining short-chain fatty acids (SCFAs) and bacteria that were specifically enriched by APS. Further in vitro experiment was carried out to test the capacity of SCFAs-producing of identified bacterium. Finally, the anti-NAFLD efficacy of identified bacterium was tested in HFD-fed mice.Our results first demonstrated the anti-NAFLD effect of APS in HFD-fed mice and the contribution of gut microbiota. Moreover, our results indicated that SCFAs, predominantly acetic acid were elevated in APS-supplemented mice and ex vivo experiment. Metagenomics revealed that D. vulgaris from Desulfovibrio genus was not only enriched by APS, but also a potent generator of acetic acid, which showed significant anti-NAFLD effects in HFD-fed mice. In addition, D. vulgaris modulated the hepatic gene expression pattern of lipids metabolism, particularly suppressed hepatic fatty acid synthase (FASN) and CD36 protein expression.Our results demonstrate that APS enriched D. vulgaris is effective on attenuating hepatic steatosis possibly through producing acetic acid, and modulation on hepatic lipids metabolism in mice. Further studies are warranted to explore the long-term impacts of D. vulgaris on host metabolism and the underlying mechanism.

Sanguisorba parviflora (Maxim.) Takeda alleviates cyclophosphamide-induced leukopenia by regulating haematopoietic cell-specific protein 1-associated protein X-1 gene expression

WHAT IS KNOWN AND OBJECTIVE

We have previously shown that the saponins of Sanguisorba parviflora (Maxim.) Takeda (Sp. T) relieved cyclophosphamide-induced myelosuppression in leukopenic mice. Haematopoietic cell-specific protein 1-associated protein X-1 (HAX-1) participated in the survival of neutrophils through the regulation of mitochondrial function. The aim of the present study was to comprehensively identify the role of HAX-1 in the mechanism of leukopenia alleviation by Sp. T.

METHODS

HAX-1 gene and protein expression levels in peripheral blood neutrophils were examined using real-time quantitative reverse transcription-polymerase chain reaction, western blot and immunohistochemical assays. Neutrophil apoptosis was measured using flow cytometry. Mitochondrial function was determined via assessments of the reactive oxygen species (ROS) generation and mitochondrial membrane potential (ΔΨm) integrity levels.

RESULTS AND DISCUSSION

The HAX-1 gene expression level in the peripheral blood neutrophils was significantly lower in patients with leukopenia than in healthy donors. The saponins of Sp. T induced HAX-1 expression and promoted myeloid progenitor cell (mEB8-ER cell) viability. HAX-1 overexpression reduced the production of ROS and maintained ΔΨm integrity. Cyclophosphamide-induced mitochondrial dysfunction and apoptosis could be abrogated by treatment with Sp. T or metformin.

WHAT IS NEW AND CONCLUSION

Our data suggest a mechanism through which Sp. T protects against chemotherapy-induced leukopenia by regulating HAX-1 gene expression in a mitochondrial-dependent manner.

Glabridin ameliorates methotrexate-induced liver injury via attenuation of oxidative stress, inflammation, and apoptosis

Despite unprecedented advances in modern medicine, no safe and effective drug is available to date for oral administration to combat drug-induced liver injury, which is a vital concern nowadays. The present study deals with the hepatoprotective effect of pure glabridin, a key phytoconstituent from Glycyrrhiza glabra with mechanistic investigations using an in-vivo methotrexate-induced liver injury model as there is no such precedent. The study was performed in the Swiss mice model where a single dose of methotrexate (40 mg/kg) was given on the 7^th day through an intraperitoneal route to induce hepatotoxicity, and glabridin as a test compound was administered orally for eleven consecutive days at 10 to 40 mg/kg. Glabridin markedly improved serum biochemical parameters (SGPT, SGOT), proinflammatory cytokine (TNF-α) level, oxidative stress markers (MDA, GSH, SOD, CAT) as compared to methotrexate alone. Alterations in methotrexate-induced liver architecture were considerably prevented by glabridin treatment as suggested by liver histopathological examination and SEM investigation. Glabridin substantially prevented methotrexate-induced down-regulation of Nrf2, & activation of NF-κB, and caused up-regulation of BAX at different dose levels. Overall, glabridin is found to protect methotrexate-induced hepatotoxicity by improving important factors for oxidative stress, inflammation, and apoptosis.

Tumor Necrosis Factor Alpha-Mediated Inflammation and Remodeling of the Extracellular Matrix Underlies Aortic Stiffening Induced by the Common Chemotherapeutic Agent Doxorubicin

[Figure: see text].

Exploring the Potential Role of the Gut Microbiome in Chemotherapy-Induced Neurocognitive Disorders and Cardiovascular Toxicity

Chemotherapy, targeting not only malignant but also healthy cells, causes many undesirable side effects in cancer patients. Due to this fact, long-term cancer survivors often suffer from late effects, including cognitive impairment and cardiovascular toxicity. Chemotherapy damages the intestinal mucosa and heavily disrupts the gut ecosystem, leading to gastrointestinal toxicity. Animal models and clinical studies have revealed the associations between intestinal dysbiosis and depression, anxiety, pain, impaired cognitive functions, and cardiovascular diseases. Recently, a possible link between chemotherapy-induced gut microbiota disruption and late effects in cancer survivors has been proposed. In this review, we summarize the current understanding of preclinical and clinical findings regarding the emerging role of the microbiome and the microbiota-gut-brain axis in chemotherapy-related late effects affecting the central nervous system (CNS) and heart functions. Importantly, we provide an overview of clinical trials evaluating the relationship between the gut microbiome and cancer survivorship. Moreover, the beneficial effects of probiotics in experimental models and non-cancer patients with neurocognitive disorders and cardiovascular diseases as well as several studies on microbiota modulations via probiotics or fecal microbiota transplantation in cancer patients are discussed.

Cardioprotective Effects of Latifolin Against Doxorubicin-Induced Cardiotoxicity by Macrophage Polarization in Mice

Latifolin, one of the major flavonoids extracted from lignum dalbergiae odoriferae, has been documented to protect the heart from acute myocardial ischemia induced by pituitrin and isoproterenol in rats and has also been found to inhibit inflammation. In this study, we aimed to investigate whether latifolin could protect the heart from doxorubicin (DOX)-induced cardiotoxicity and elucidate its underlying mechanisms. Male mice were treated with an intraperitoneal dose of DOX (20 mg/kg) plus oral latifolin at a dose of 50 or 100 mg/kg for 12 days. After exposure, we assessed cardiac function, myocardial injury, and macrophage polarization in excised cardiac tissue. Our results demonstrated that latifolin prevented DOX-induced cardiac dysfunction and produced macrophage polarization in mice challenged with latifolin. In cultured peritoneal macrophages, latifolin significantly reduced inflammatory cytokines (P < 0.05). Furthermore, latifolin remarkably decreased the percentage of macrophage M1/M2 polarization (P < 0.05). The results from the present study highlight the benefits of treatment with latifolin in DOX-induced cardiotoxicity, and the mechanism involved in mediating the polarization phenotype change of M1/M2 macrophages.

Gut microbiome - A potential mediator of pathogenesis in heart failure and its comorbidities: State-of-the-art review

Gut microbiome (GMB) has been increasingly recognized as a contributor to development and progression of heart failure (HF), immune-mediated subtypes of cardiomyopathy (myocarditis and anthracycline-induced cardiotoxicity), response to certain cardiovascular drugs, and HF-related comorbidities, such as chronic kidney disease, cardiorenal syndrome, insulin resistance, malnutrition, and cardiac cachexia. Gut microbiome is also responsible for the "gut hypothesis" of HF, which explains the adverse effects of gut barrier dysfunction and translocation of GMB on the progression of HF. Furthermore, accumulating evidence has suggested that gut microbial metabolites, including short chain fatty acids, trimethylamine N-oxide (TMAO), amino acid metabolites, and bile acids, are mechanistically linked to pathogenesis of HF, and could, therefore, serve as potential therapeutic targets for HF. Even though there are a variety of proposed therapeutic approaches, such as dietary modifications, prebiotics, probiotics, TMAO synthesis inhibitors, and fecal microbial transplant, targeting GMB in HF is still in its infancy and, indeed, requires further preclinical and clinical evidence. In this review, we aim to highlight the role gut microbiome plays in HF pathophysiology and its potential as a novel therapeutic target in HF.

Doxorubicin increases permeability of murine small intestinal epithelium and cultured T84 monolayers

Enteric bacteria and/or their products are necessary for doxorubicin (DXR)-induced small intestine mucosal damage. While DXR does not induce gross loss of epithelium, others have shown elevated serum endotoxin after DXR administration. However, the mechanism of movement is unknown. We hypothesized that DXR treatment resulted in increased paracellular translocation of bacteria or bacterial products through the small intestinal epithelium. We measured permeability after DXR administration using transepithelial resistance and macromolecular flux and assessed tight junctional gene expression and protein localization both in vitro using T84 cells and ex vivo using murine jejunum. DXR treatment increased flux of 4 kDa dextrans in mouse jejenum, but increased flux of 4, 10 and 20 kDa dextrans in T84 cells. Following DXR, we observed increased permeability, both in vitro and ex vivo, independent of bacteria. DXR induced increased expression of Cldn2 and Cldn4 in murine small intestine but increased only CLDN2 expression in T84 cells. DXR treatment induced disorganization of tight junctional proteins. We conclude that DXR increases paracellular transit of small macromolecules, including bacterial products, through the epithelium, by altering expression of tight junctional components and dynamic loosening of cellular tight junctions.

Glabridin Attenuates the Retinal Degeneration Induced by Sodium Iodate In Vitro and In Vivo

Background

Age-related macular degeneration (AMD) is one of the major causes of blindness in the elderly over the age of 60. AMD is divided into dry AMD and wet AMD. Although there are certain treatment methods for wet age-related macular degeneration (AMD), there are no effective treatments for dry AMD yet, and finding new drugs or treatment methods for dry AMD has become a priority. For this purpose, this study explored Glabridin (Glab), an isoflavane found in the root extract of licorice, which has never been investigated in relation to eye diseases.

Purpose

To investigate the effect of Glab on the sodium iodate (NaIO₃) induced retinal degeneration in vitro and in vivo.

Methods

In vitro, cell viability and cytotoxicity were tested with methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay among the groups of ARPE-19 cells. The cell apoptosis was tested with Hoechst 33342 staining and flow cytometry. The level of Reactive oxygen species (ROS) was measured to check the effect on oxidative stress. The protein expressions of phosphorylation of ERK1/2 and p38 were detected by Western blotting. In vivo, C57BL/6J mice were pretreated with Glab intraperitoneally for one week and continued for 4 weeks. NaIO₃ was given to mice through tail vein intravenous injection after 1 week of Glab administration. The retinas of mice were monitored by Optical coherence tomography (OCT) and electroretinography (ERG) at 1w, 2w, 3w, and 4w, respectively, followed by H&E staining.

Results

In vitro, the Glab protected the retinal pigment epithelial (RPE) cells against oxidative stress and apoptosis by inhibiting phosphorylation of ERK1/2 and the p38 MAPK pathway. In vivo, Glab significantly prevented retinal damage by stopping the progression of retinal degeneration and reducing the formation of deposits on the RPE layer induced by NaIO₃. According to the findings of electroretinogram (ERG), Glab helped to maintain the normal function of the retina.

Conclusion

Glabridin has a protective effect against retinal degeneration. It is suggested that Glab be further investigated for the treatment of retinal degeneration diseases.

Doxorubicin-Induced Oxidative Stress and Endothelial Dysfunction in Conduit Arteries Is Prevented by Mitochondrial-Specific Antioxidant Treatment

Background

Doxorubicin (DOXO) chemotherapy increases risk for cardiovascular disease in part by inducing endothelial dysfunction in conduit arteries. However, the mechanisms mediating DOXO-associated endothelial dysfunction in (intact) arteries and treatment strategies are not established.

Objectives

We tested the hypothesis that DOXO impairs endothelial function in conduit arteries via excessive mitochondrial reactive oxygen species (ROS) and that these effects could be prevented by treatment with a mitochondrial-targeted antioxidant (MitoQ).

Methods

Endothelial function (endothelium-dependent dilation [EDD] to acetylcholine) and vascular mitochondrial ROS were assessed 4 weeks following administration (10 mg/kg intraperitoneal injection) of DOXO. A separate cohort of mice received chronic (4 weeks) oral supplementation with MitoQ (drinking water) for 4 weeks following DOXO.

Results

EDD in isolated pressurized carotid arteries was 55% lower 4 weeks following DOXO (peak EDD, DOXO: 42 ± 7% vs. sham: 94 ± 3%; p = 0.006). Vascular mitochondrial ROS was 52% higher and manganese (mitochondrial) superoxide dismutase was 70% lower after DOXO versus sham (p = 0.0008). Endothelial function was rescued by administration of the mitochondrial-targeted antioxidant, MitoQ, to the perfusate. Exposure to plasma from DOXO-treated mice increased mitochondrial ROS in cultured endothelial cells. Analyses of plasma showed differences in oxidative stress-related metabolites and a marked reduction in vascular endothelial growth factor A in DOXO mice, and restoring vascular endothelial growth factor A to sham levels normalized mitochondrial ROS in endothelial cells incubated with plasma from DOXO mice. Oral MitoQ supplementation following DOXO prevented the reduction in EDD (97 ± 1%; p = 0.002 vs. DOXO alone) by ameliorating mitochondrial ROS suppression of EDD.

Conclusions

DOXO-induced endothelial dysfunction in conduit arteries is mediated by excessive mitochondrial ROS and ameliorated by mitochondrial-specific antioxidant treatment. Mitochondrial ROS is a viable therapeutic target for mitigating arterial dysfunction with DOXO.

Cardiac dysfunction in cancer patients: beyond direct cardiomyocyte damage of anticancer drugs: novel cardio-oncology insights from the joint 2019 meeting of the ESC Working Groups of Myocardial Function and Cellular Biology of the Heart

In western countries, cardiovascular (CV) disease and cancer are the leading causes of death in the ageing population. Recent epidemiological data suggest that cancer is more frequent in patients with prevalent or incident CV disease, in particular, heart failure (HF). Indeed, there is a tight link in terms of shared risk factors and mechanisms between HF and cancer. HF induced by anticancer therapies has been extensively studied, primarily focusing on the toxic effects that anti-tumour treatments exert on cardiomyocytes. In this Cardio-Oncology update, members of the ESC Working Groups of Myocardial Function and Cellular Biology of the Heart discuss novel evidence interconnecting cardiac dysfunction and cancer via pathways in which cardiomyocytes may be involved but are not central. In particular, the multiple roles of cardiac stromal cells (endothelial cells and fibroblasts) and inflammatory cells are highlighted. Also, the gut microbiota is depicted as a new player at the crossroads between HF and cancer. Finally, the role of non-coding RNAs in Cardio-Oncology is also addressed. All these insights are expected to fuel additional research efforts in the field of Cardio-Oncology.

Osteocrin attenuates inflammation, oxidative stress, apoptosis, and cardiac dysfunction in doxorubicin-induced cardiotoxicity

Background

Inflammation, oxidative stress, and apoptosis contribute to the evolution of doxorubicin (DOX)‐induced cardiotoxicity. Osteocrin (OSTN) is a novel secretory peptide mainly derived from the bone and skeletal muscle, and plays critical roles in regulating bone growth and physical endurance. Inspiringly, OSTN was also reported to be abundant in the myocardium that functioned as a therapeutic agent against cardiac rupture and congestive heart failure in mice after myocardial infarction. Herein, we investigated the role and potential mechanism of OSTN in DOX‐induced cardiotoxicity.

Methods

Cardiac‐restrict OSTN overexpression was performed by the intravenous injection of a cardiotropic AAV9 vector, and subsequently the mice received 15 mg/kg DOX injection (i.p., once) to induce acute cardiac injury. Besides, H9C2 cell lines were used to assess the possible role of OSTN in vitro by incubating with recombinant human OSTN or small interfering RNA against Ostn (siOstn). To clarify the involvement of protein kinase G (PKG), KT5823 and siPkg were used in vivo and in vitro. Mice were also administrated intraperitoneally with 5 mg/kg DOX weekly for consecutive 3 weeks at a cumulative dose of 15 mg/kg to mimic the cardiotoxic effects upon chronic DOX exposure.

Results

OSTN treatment notably attenuated, whereas OSTN silence exacerbated inflammation, oxidative stress, and cardiomyocyte apoptosis in DOX‐treated H9C2 cells. Besides, cardiac‐restrict OSTN‐overexpressed mice showed an alleviated cardiac injury and malfunction upon DOX injection. Mechanistically, we found that OSTN activated PKG, while PKG inhibition abrogated the beneficial effect of OSTN in vivo and in vitro. As expected, OSTN overexpression also improved cardiac function and survival rate in mice after chronic DOX treatment.

Conclusions

OSTN protects against DOX‐elicited inflammation, oxidative stress, apoptosis, and cardiac dysfunction via activating PKG, and cardiac gene therapy with OSTN provides a novel therapeutic strategy against DOX‐induced cardiotoxicity.

Prediction of mucositis risk secondary to cancer therapy: a systematic review of current evidence and call to action

PURPOSE

Despite advances in personalizing the efficacy of cancer therapy, our ability to identify patients at risk of severe treatment side effects and provide individualized supportive care is limited. This is particularly the case for mucositis (oral and gastrointestinal), with no comprehensive risk evaluation strategies to identify high-risk patients. We, the Multinational Association for Supportive Care in Cancer/International Society for Oral Oncology (MASCC/ISOO) Mucositis Study Group, therefore aimed to systematically review current evidence on that factors that influence mucositis risk to provide a foundation upon which future risk prediction studies can be based.

METHODS

We identified 11,018 papers from PubMed and Web of Science, with 197 records extracted for full review and 113 meeting final eligibility criteria. Data were then synthesized into tables to highlight the level of evidence for each risk predictor.

RESULTS

The strongest level of evidence supported dosimetric parameters as key predictors of mucositis risk. Genetic variants in drug-metabolizing pathways, immune signaling, and cell injury/repair mechanisms were also identified to impact mucositis risk. Factors relating to the individual were variably linked to mucositis outcomes, although female sex and smoking status showed some association with mucositis risk.

CONCLUSION

Mucositis risk reflects the complex interplay between the host, tumor microenvironment, and treatment specifications, yet the large majority of studies rely on hypothesis-driven, single-candidate approaches. For significant advances in the provision of personalized supportive care, coordinated research efforts with robust multiplexed approaches are strongly advised.

Shenmai Injection Protects Against Doxorubicin-Induced Cardiotoxicity via Maintaining Mitochondrial Homeostasis

Shenmai injection (SMI), as a patented traditional Chinese medicine, is extracted from Panax ginseng and Ophiopogon japonicus. It commonly used in the treatment of cardiovascular disease and in the control of cardiac toxicity induced by doxorubicin (DOX) treatment. However, its anti-cardiotoxicity mechanism remains unknown. The purpose of this study was to investigate the underlying mitochondrial protective mechanisms of SMI on DOX-induced myocardial injury. The cardioprotective effect of SMI against DOX-induced myocardial damage was evaluated in C57BL/6 mice and H9c2 cardiomyocytes. In vivo, myocardial injury, apoptosis and phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB/Akt)/glycogen synthase kinase 3 beta (GSK-3β) signaling pathway related proteins were measured. In vitro, apoptosis, mitochondrial superoxide, mitochondrial membrane potential, mitochondrial morphology, levels of mitochondrial fission/fusion associated proteins, mitochondrial respiratory function, and AMP-activated protein kinase (AMPK) activity were assessed. To further elucidate the regulating effects of SMI on AMPK and PI3K/Akt/GSK-3β signaling pathway, compound C and LY294002 were utilized. In vivo, SMI decreased mortality rate, levels of creatine kinase, and creatine kinase-MB. SMI significantly prevented DOX-induced cardiac dysfunction and apoptosis, decreased levels of Bax/Bcl-2 and cleaved-Caspase3, increased levels of PI3K, p-Akt, and p-GSK-3β. In vitro, SMI rescued DOX-injured H9c2 cardiomyocytes from apoptosis, excessive mitochondrial reactive oxygen species production and descending mitochondrial membrane potential, which were markedly suppressed by LY294002. SMI increased ratio of L-OPA1 to S-OPA1, levels of AMPK phosphorylation, and DRP1 phosphorylation (Ser637) in order to prevent DOX-induced excessive mitochondrial fission and insufficient mitochondrial fusion. In conclusion, SMI prevents DOX-induced cardiotoxicity, inhibits mitochondrial oxidative stress and mitochondrial fragmentation through activation of AMPK and PI3K/Akt/GSK-3β signaling pathway.

Multi-walled carbon nanotubes exacerbate doxorubicin-induced cardiotoxicity by altering gut microbiota and pulmonary and colonic macrophage phenotype in mice

Epidemiologic studies show that the levels of air pollutants and particulate matter are positively associated with the morbidity and mortality of cardiovascular diseases. Here we demonstrate that the intratracheal instillation of multi-walled carbon nanotubes (MWCNTs), a standard fine particle, exacerbate doxorubicin (DOX)-induced cardiotoxicity in mice through altering gut microbiota and pulmonary and colonic macrophage phenotype. MWCNTs (25 μg/kg per day, 5 days a week for 3 weeks) promoted cardiotoxicity and apoptosis in the DOX (2 mg/kg, twice a week for 5 weeks)-treated C57BL/6 mice. MWCNTs exaggerated DOX-induced gut microbiota dysbiosis characterized by the increased abundances of Helicobacteraceae and Coriobacteriaceae. In addition, MWCNTs promoted DOX-induced M1-like polarization of colonic macrophages with an increase in TNF-α, IL-1β and CC chemokine ligand 2 in peripheral blood. Importantly, treatment with the antibiotics attenuated MWCNTs plus DOX-induced apoptosis of cardiomyocytes and M1-like polarization of colonic macrophages. The fecal microbiota transplantation demonstrated that MWCNTs exaggerated DOX-induced cardiotoxicity with M1-like polarization of colonic macrophages. The conditioned medium from MWCNTs-treated pulmonary macrophages promoted DOX-induced gut microbiota dysbiosis and colonic macrophage polarization. Furthermore, the co-culture of macrophages and fecal bacteria promoted M1-like macrophage polarization and their production of TNF-α and IL-1β, and thereby exacerbated the effects of MWCNTs. Moreover, IL-1β and TNF-α blockade, either alone or in combination attenuated MWCNTs-exacerbated cardiotoxicity. In summary, MWCNTs exacerbate DOX-induced cardiotoxicity in mice through gut microbiota and pulmonary and colonic macrophage interaction. Our findings identify a novel mechanism of action of inhaled particle-driven cardiotoxicity.

Bioactive Candy: Effects of Licorice on the Cardiovascular System

Licorice, today chiefly utilized as a flavoring additive in tea, tobacco and candy, is one of the oldest used herbs for medicinal purposes and consists of up to 300 active compounds. The main active constituent of licorice is the prodrug glycyrrhizin, which is successively converted to 3β-monoglucuronyl-18β-glycyrrhetinic acid (3MGA) and 18β-glycyrrhetinic acid (GA) in the intestines. Despite many reported health benefits, 3MGA and GA inhibit the 11-β-hydrogenase type II enzyme (11β-HSD2) oxidizing cortisol to cortisone. Through activation of mineralocorticoid receptors, high cortisol levels induce a mild form of apparent mineralocorticoid excess in the kidney and increase systemic vascular resistance. Continuous inhibition of 11β-HSD2 related to excess licorice consumption will create a state of hypernatremia, hypokalemia and increased fluid volume, which can cause serious life-threatening complications especially in patients already suffering from cardiovascular diseases. Two recent meta-analyses of 18 and 26 studies investigating the correlation between licorice intake and blood pressure revealed statistically significant increases both in systolic (5.45 mmHg) and in diastolic blood pressure (3.19/1.74 mmHg). This review summarizes and evaluates current literature about the acute and chronic effects of licorice ingestion on the cardiovascular system with special focus on blood pressure. Starting from the molecular actions of licorice (metabolites) inside the cells, it describes how licorice intake is affecting the human body and shows the boundaries between the health benefits of licorice and possible harmful effects.

Zn(ii)-Curcumin supplementation alleviates gut dysbiosis and zinc dyshomeostasis during doxorubicin-induced cardiotoxicity in rats

Doxorubicin is a powerful anticancer agent used to treat a variety of human neoplasms. However, the clinical use of doxorubicin is hampered by cardiotoxicity and effective cardioprotective adjuvants do not exist. Dietary zinc, an essential nutrient, is required to maintain steady-state tissue zinc levels and intestinal homeostasis and may yield therapeutic benefits in diseases associated with zinc dysregulation or gut dysbiosis. Here, we investigated the effects of dietary Zn(ii)-curcumin (ZnCM) solid dispersions on gut dysbiosis and zinc dyshomeostasis during doxorubicin-induced cardiotoxicity in rats. Rats were injected with multiple low doses of doxorubicin and orally administered ZnCM daily over four weeks. Daily administration of ZnCM not only alleviated Dox-induced gut dysbiosis-as indicated by the increased Firmicutes-to-Bacteroidetes ratio and the maintenance of the relative abundances of major beneficial bacteria including Clostridium_XIVa, Clostridium_IV, Roseburia, Butyricicoccus and Akkermansia-but also maintained intestinal barrier integrity and decreased the lipopolysaccharide (LPS) contents of feces and plasma. ZnCM also significantly attenuated doxorubicin-induced zinc dyshomeostasis, which was mirrored by preservation of zinc levels and expression of zinc-related transporters. Furthermore, ZnCM significantly improved heart function and reduced cardiomyocyte apoptosis and myocardial injury in doxorubicin-treated rats. Notably, the regulation of zinc homeostasis and cardioprotective and microbiota-modulating effects of ZnCM were transmissible through horizontal feces transfer from ZnCM-treated rats to normal rats. Thus, ZnCM supplementation has potential as an effective therapeutic strategy to alleviate gut dysbiosis and zinc dyshomeostasis during doxorubicin-induced cardiotoxicity.