5-fluorouracil causes endothelial cell senescence: potential protective role of glucagon-like peptide 1

The Potential Role of GLP1-RAs Against Anticancer-Drug Cardiotoxicity: A Scoping Review

Background: GLP1 receptor agonists (GLP1-RAs) have become a central component in the treatment of type 2 diabetes mellitus (T2DM) and are gaining prominence in the cardiovascular field. Semaglutide and other GLP1-RA molecules possess cardioprotective properties. Cardiotoxicity, a term used to refer to cardiovascular disease caused by anticancer treatment, is a collection of common and severe conditions. Its pharmacological prevention or mitigation is a clinical unmet need as options are few and limited to some specific clinical settings. GLP1-RAs have a promising pharmacological profile given their activity on a number of pathophysiological targets and signaling pathways including oxidative stress, autophagy, and STAT3 activation. Interestingly, abnormalities in some of the GLP-1-modulated pathways have been linked to cardiotoxicity. This scoping review aims to map the extent and assess the main characteristics of research on the role of GLP1-RAs in the prevention and/or mitigation of anticancer-related cardiotoxicity. Methods: The selection process led to the inclusion of thirteen studies chosen from reports retrieved through the search string: ("semaglutide" OR "exenatide" OR "liraglutide" OR "dulaglutide" OR "tirzepatide" OR "GLP1 receptor agonist" OR "GLP1RA" OR "GLP1-RA" OR "GLP1" OR "Glucagon-like Peptide-1 Agonists") AND ("cardioncology" OR "cardiotoxicity" OR "chemotherapy" OR "anti-cancer treatment" OR "anti-cancer therapy"). The study complied with the PRISMA guidelines on scoping reviews. Results: Two studies were clinical and conducted on registries, eight used animal models, two were conducted on cell cultures, and one was conducted on both animal models and cell cultures. Evidence in favor of cardioprotection and a number of putative mechanisms emerged. Conclusions: Evidence on GLP1-RAs' effect on cardiotoxicity is limited in both quantity and quality and suffers from poor study standardization. However, most included studies documented a rigorously defined cardioprotective effect and demonstrated changes in several pathophysiologically relevant targets and pathways, including NF-κB, IL-6, reactive oxygen species, and caspase-3. Further clinical studies are warranted.

Thinking Outside the Therapeutic Box: The Potential of Polyphenols in Preventing Chemotherapy-Induced Endothelial Dysfunction

The numerous side effects and adverse health implications associated with chemotherapies have long plagued the field of cancer care. Whilst in some cases a curative measure, this highly toxic intervention consistently scores poorly on quantitative measures of tolerability and safety. Of these side effects, cardiac and microvascular defects pose the greatest health risk and are the leading cause of death amongst cancer survivors who do not succumb to relapse. In fact, in many low-grade cancers, the risk of recurrence is far outweighed by the cardiovascular risk of morbidity. As such, there is a pressing need to improve outcomes within these populations. Polyphenols are a group of naturally occurring metabolites that have shown potential vasoprotective effects. Studies suggest they possess antioxidant and anti-inflammatory activities, in addition to directly modulating vascular signalling pathways and gene expression. Leveraging these properties may help counteract the vascular toxicity induced by chemotherapy. In this review, we outline the main mechanisms by which the endothelium is damaged by chemotherapeutic agents and discuss the ability of polyphenols to counteract such side effects. We suggest future considerations that may help overcome some of the published limitations of these compounds that have stalled their clinical success. Finally, we briefly explore their pharmacological properties and how novel approaches could enhance their efficacy while minimising treatment-related side effects.

A gene signature associated with cellular senescence serves as an important prognostic indicator in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is a lethal tumor. Predicting the prognosis of HCC remains challenging. Cellular senescence, which is one of the hallmarks of cancer, and its related prognostic-gene signature can provide critical information for clinical decision making. Our objective was to investigate the role of cellular senescence in HCC.

Methods

The RNA sequencing data and clinical information of HCC patients from The Cancer Genome Atlas (TCGA) database were obtained. The HCC subtypes and a senescence score model were established to predict the prognosis of HCC.

Results

In this study, patients from TCGA-HCC dataset were stratified into low- and high-risk groups based on cellular senescence-related genes. The analysis of the various subtypes revealed that the distribution of Cluster 1 (C1) was significantly correlated with numerous factors, including age, sex, pathological T stage, tumor node metastasis (TNM) classification, and grade staging. Further, the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that the upregulated genes in the high-risk C1 group were primarily engaged in pathways related to the cell cycle, DNA replication, cellular senescence, extracellular matrix (ECM)-receptor interactions, and the mechanisms of mismatch repair. Conversely, the 90 downregulated genes were mainly associated with metabolic pathways, chemical carcinogenesis involving DNA adducts, complement and coagulation cascades, and the peroxisome proliferator-activated receptor (PPAR) signaling pathway. The resultant boxplots revealed significant differences in the populations of immune cells, such as B cells, endothelial cells, natural killer (NK) cells, macrophages, cluster of differentiation (CD)4+ T cells, and CD8+ T cells, in the C1 HCC samples compared to the C2 HCC samples. Additionally, the prognostic outcomes of the HCC patients were predicted using a cellular senescence-related gene model that included VDAC2, CXCL8, MYBL2, RAD9A, LIN52, RHEB, GADD45G, E2F5, MAP2K2, CDC25A, PPP1CB, and HRAS.

Conclusions

This study established a prognostic model of HCC based on cellular senescence-related gene expression. Our findings may provide insights that can be used to develop novel potential targeted therapies.

Persisting blood-brain barrier disruption following cisplatin treatment in a mouse model of chemotherapy-associated cognitive impairment

Chemotherapy-related cognitive impairment, commonly referred to as "chemobrain," significantly affects cancer survivors' quality of life, yet its underlying mechanisms remain unclear. Most chemotherapeutic agents cannot cross the blood-brain barrier (BBB), yet they cause central nervous system side effects, suggesting alternative pathways of toxicity. Given that these drugs interact with the cerebrovascular endothelium at their highest concentrations, it is logical to hypothesize that endothelial damage contributes to these effects. Our recent studies demonstrated that paclitaxel-induced cognitive impairment in a mouse model results in a partial BBB disruption and subsequent neuroinflammation, mediated by chemotherapy-induced endothelial senescence. In this pilot study, we used two-photon microscopy to assess BBB permeability in mice receiving a clinically relevant cisplatin regimen, evaluating the leakage of fluorescent dextran tracers of varying molecular weights. Two months post-treatment, cisplatin-treated mice exhibited significantly increased BBB permeability to smaller molecular tracers (40 kDa, 3 kDa, and 0.3 kDa) compared to controls, indicating sustained BBB disruption. These results align with our findings for paclitaxel and suggest that chemotherapy-induced endothelial damage and senescence play a central role in cognitive impairments. Interventions targeting endothelial health could mitigate these long-term effects, improving cognitive outcomes for cancer survivors.

Inhibition of glutaminase elicits senolysis in therapy-induced senescent melanoma cells

The cyclin D1-Cyclin-Dependent Kinases 4 and 6 (CDK4/6) complex is crucial for the development of melanoma. We previously demonstrated that targeting CDK4/6 using small molecule inhibitors (CDK4/6i) suppresses BrafV600E melanoma growth in vitro and in vivo through induction of cellular senescence. However, clinical trials investigating CDK4/6i in melanoma have not yielded successful outcomes, underscoring the necessity to enhance the therapeutic efficacy of CDK4/6i. Accumulated research has shown that while senescence initially suppresses cell proliferation, a prolonged state of senescence eventually leads to tumor relapse by altering the tumor microenvironment, suggesting that removal of those senescent cells (in a process referred to as senolysis) is of clinical necessity to facilitate clinical response. We demonstrate that glutaminase 1 (GLS1) expression is specifically upregulated in CDK4/6i-induced senescent BrafV600E melanoma cells. Upregulated GLS1 expression renders BrafV600E melanoma senescent cells vulnerable to GLS1 inhibitor (GLS1i). Furthermore, we demonstrate that this senolytic approach targeting upregulated GLS1 expression is applicable even though those cells developed resistance to the BrafV600E inhibitor vemurafenib, a frequently encountered substantial clinical challenge to treating patients. Thus, this novel senolytic approach may revolutionize current CDK4/6i mediated melanoma treatment if melanoma cells undergo senescence prior to developing resistance to CDK4/6i. Given that we demonstrate that a low dose of vemurafenib induced senescence, which renders BrafV600E melanoma cells susceptible to GLS1i and recent accumulated research shows many cancer cells undergo senescence in response to chemotherapy, radiation, and immunotherapy, this senolytic therapy approach may prove applicable to a wide range of cancer types once senescence and GLS1 expression are induced.

Chloramphenicol alleviates 5-fluorouracil-induced cellular senescence through activation of autophagy

5-Fluorouracil (5-FU) is a first-line treatment for colorectal cancer, but side effects such as severe diarrhea are common in clinical use and have been linked to its induction of normal cell senescence. Chloramphenicol (CAP) is an antibiotic commonly used to treat typhoid or anaerobic infections, but its senescence-related aspects have not been thoroughly investigated. Here, we used 5-FU to induce senescence in human umbilical vein endothelial cells (HUVECs) and investigated the relationship between CAP and cellular senescence at the cellular level. In a model of cellular senescence induced by 5-FU treatment, we discovered that CAP treatment reversed the rise in the percentage of senescence-associated galactosidase (SA-β-gal)-positive cells and decreased the expression of senescence-associated proteins (p16), senescence-associated genes (p21), and senescence-associated secretory phenotypes (SASPs: IL-6, TNF-α). In addition, CAP subsequently restored the autophagic process inhibited by 5-FU and upregulated the levels of autophagy-related proteins. Mechanistically, we found that CAP restored autophagic flux by inhibiting the mTOR pathway, which in turn alleviated FU-induced cellular senescence. Our findings suggest that CAP may help prevent cellular senescence and restore autophagy, opening up new possibilities and approaches for the clinical management of colorectal cancer.

Effect of hypoxia on proliferation and differentiation of induced pluripotent stem cell-derived mesenchymal stem cells

Although mesenchymal stem cells (MSCs) are extensively applied in the regenerative field, the majority of MSCs die after a few weeks of transplantation. Therefore, hypoxia pre-conditioning is a crucial step in increasing the MSCs' tolerance to physiological conditions. Meanwhile, induced pluripotent stem cell-derived MSCs (iMSCs) were proposed as a possible alternative to MSCs, and recently, the interest is growing in applying iMSCs in the regenerative field. This study examined the effect of hypoxia pre-conditioning on the proliferation, viability, and differentiation of iMSCs. Both iMSCs and MSCs were subjected to two rounds of severe short-term hypoxia (1 % O2 for 24h). After that, iMSCs and MSCs were characterized by testing their surface markers' expression, proliferation, viability, oxidative stress, and differentiation potential. Our findings revealed that hypoxia did not have a consistent effect among all the analyzed lines: the severe short-term hypoxia (1 % O2) reduced iMSCs proliferation, cell viability, and MMP while showing a benign effect on surface markers expression, colony formation, ROS accumulation, and osteogenic and adipogenic differentiation. Though hypoxia adversely affected iMSCs' proliferation, this does not necessarily mean that hypoxia is harmful to iMSCs; on the contrary, our results suggest that short-term hypoxia might have a beneficial long-term effect on the proliferation of iMSCs. Thus, the effect of hypoxia on proliferation, viability, and differentiation should also be tested after a long recovery period from iMSCs. Our next step will be to test the effect of hypoxia for a longer period besides uncovering the changes in the expression profile of hypoxic iMSCs.

Losmapimod ameliorates doxorubicin-induced cardiotoxicity through attenuating senescence and inflammatory pathways

Irreversible cardiotoxicity limits the clinical application of doxorubicin (DOX). DOX-induced cardiotoxicity has been associated with induction of senescence and activation of the p38 MAPK pathway. Losmapimod (LOSM), an orally active p38 MAPK inhibitor, is an anti-inflammatory agent with cardioprotective effects. Nevertheless, the effect of LOSM against DOX-induced cardiotoxicity has not been reported. In this study, we determined the effects of LOSM on DOX-induced chronic cardiotoxicity in C57BL/6 N mice. Five-week-old C57BL/6 N mice were fed diet containing LOSM (estimated daily intake 12 mg/kg/day) or a control diet for four days. Thereafter, mice were randomized to receive six weekly intraperitoneal injections of either DOX (4 mg/kg) or saline. Three days after the last injection, cardiac function was assessed by trans-thoracic echocardiography. Activation of p38, JNK, and ERK1/2 MAPKs were assessed by immunoblotting in the heart and liver. Gene expressions of senescence, inflammatory, oxidative stress, and mitochondrial function markers were quantified using real-time PCR and serum inflammatory markers were assessed by Luminex. Our results demonstrated that LOSM attenuated p38 MAPK activation, ameliorated DOX-induced cardiac dysfunction, and abrogated DOX-induced expression of the senescence marker p21Cip1. Additionally, LOSM demonstrated anti-inflammatory effects, with reduced cardiac Il-1α and Il-6 gene expression in DOX-treated mice. Systemic inflammation, assessed by serum cytokine levels, showed decreased IL-6 and CXCL1 in both DOX-treated mice and mice on LOSM diet. LOSM significantly increased mitofusin2 gene expression, which may enhance mitochondrial fusion. These findings underscore the potential therapeutic efficacy of p38 MAPK inhibition, exemplified by LOSM, in ameliorating DOX-induced cardiotoxicity, senescence, and inflammation.

Senescence in the bone marrow microenvironment: A driver in development of therapy-related myeloid neoplasms

Therapy-related myeloid neoplasms (t-MN) are a growing concern due to the continued use of cytotoxic therapies to treat malignancies. Cytotoxic therapies have been shown to drive therapy-induced senescence in normal tissues, including in the bone marrow microenvironment (BMME), which plays a crucial role in supporting normal hematopoiesis. This review examines recent work that focuses on the contribution of BMME senescence to t-MN pathogenesis, as well as offers a perspective on potential opportunities for therapeutic intervention.

Dasabuvir alleviates 5-fluorouracil-induced intestinal injury through anti-senescence and anti-inflammatory

5-Fluorouracil (5-Fu) is a basic drug that is used to treat colorectal cancer. Patients who receive 5-Fu chemotherapy often experience side effects that affect the digestive system, such as intestinal injury and diarrhoea, which significantly affect patient compliance with anticancer treatment and quality of life. Therefore, identifying approaches to treat or prevent these side effects is urgent. Dasabuvir (DSV) is a hepatitis C virus inhibitor, but its impact on 5-Fu-induced intestinal injury remains unknown. Our study investigated the effects of DSV on 5-Fu-induced intestinal injury in HUVECs, HIECs and male BALB/c mice. We found that 5-Fu caused intestinal damage by inducing senescence, increasing inflammatory factor expression, and generating oxidative stress. Compared with 5-Fu treatment alone, DSV inhibited senescence by reducing senescence-β-galactosidase (SA-β-gal) activity, the senescence-associated secretory phenotype (SASP, including IL-1, IL-6, and TNF-α) and senescence marker expression levels (p16, p21, and p53). Moreover, the anti-senescence effect of DSV was achieved by inhibiting the mTOR signaling pathway. DSV increased antioxidant enzyme levels and alleviated intestinal tissue injury in mice. In addition, DSV suppressed the 5-Fu-induced increase the diarrhoea scores and ameliorated the weight loss, food intake and water intake of the mice. Overall, this study indicated that DSV could be used to treat chemotherapy-induced intestinal damage.

Ischaemic heart disease in patients with cancer

Cardiologists are encountering a growing number of cancer patients with ischaemic heart disease (IHD). Several factors account for the interrelationship between these two conditions, in addition to improving survival rates in the cancer population. Established cardiovascular (CV) risk factors, such as hypercholesterolaemia and obesity, predispose to both IHD and cancer, through specific mechanisms and via low-grade, systemic inflammation. This latter is also fuelled by clonal haematopoiesis of indeterminate potential. Furthermore, experimental work indicates that IHD and cancer can promote one another, and the CV or metabolic toxicity of anticancer therapies can lead to IHD. The connections between IHD and cancer are reinforced by social determinants of health, non-medical factors that modify health outcomes and comprise individual and societal domains, including economic stability, educational and healthcare access and quality, neighbourhood and built environment, and social and community context. Management of IHD in cancer patients is often challenging, due to atypical presentation, increased bleeding and ischaemic risk, and worse outcomes as compared to patients without cancer. The decision to proceed with coronary revascularization and the choice of antithrombotic therapy can be difficult, particularly in patients with chronic coronary syndromes, necessitating multidisciplinary discussion that considers both general guidelines and specific features on a case by case basis. Randomized controlled trial evidence in cancer patients is very limited and there is urgent need for more data to inform clinical practice. Therefore, coexistence of IHD and cancer raises important scientific and practical questions that call for collaborative efforts from the cardio-oncology, cardiology, and oncology communities.

Interferon-regulatory factor-1 boosts bevacizumab cardiotoxicity by the vascular endothelial growth factor A/14-3-3γ axis

AIM

Myocardial injury is a significant cause of death. This study investigated the role and underlying mechanism of interferon-regulatory factor-1 (IRF1) in bevacizumab (BVZ)-induced cardiomyocyte injury.

METHODS AND RESULTS

HL-1 cells and C57BL/6 mice receiving BVZ treatment were used to establish in vitro and in vivo models of myocardial injury. The relationship between VEGFA and 14-3-3γ was verified through co-immunoprecipitation and Glutathione S Transferase (GST) pull-down assay. Cell viability and apoptosis were analysed by MTT, propidium iodide (PI) staining and flow cytometry. The release of lactate dehydrogenase (LDH), cardiac troponins T (cTnT), and creatine kinase MB (CK-MB) was measured using the enzyme linked immunosorbent assay. The effects of knocking down IRF1 on BVZ-induced mice were analysed in vivo. IRF1 levels were increased in BVZ-treated HL-1 cells. BVZ treatment induced apoptosis, inhibited cell viability, and promoted the release of LDH, cTnT, and CK-MB. IRF1 silencing suppressed BVZ-induced myocardial injury, whereas IRF1 overexpression had the opposite effect. IRF1 regulated VEGFA expression by binding to its promoter, with the depletion of VEGFA or 14-3-3γ reversing the effects of IRF1 knockdown on the cell viability and apoptosis of BVZ-treated HL-1 cells. 14-3-3γ overexpression promoted cell proliferation, inhibited apoptosis, and reduced the release of LDH, cTnT, and CK-MB, thereby alleviating BVZ-induced HL-1 cell damage. In vivo, IRF1 silencing alleviated BVZ-induced cardiomyocyte injury by regulating the VEGFA/14-3-3γ axis.

CONCLUSION

The IRF1-mediated VEGFA/14-3-3γ signalling pathway promotes BVZ-induced myocardial injury. Our study provides evidence for potentially new target genes for the treatment of myocardial injury.

Impaired microvascular reactivity in patients treated with 5-fluorouracil chemotherapy regimens: Potential role of endothelial dysfunction

Background

5-fluorouracil (5-FU) is the second most common cancer chemotherapy associated with short- and long-term cardiotoxicity. Although the mechanisms mediating these toxicities are not well understood, patients often present with symptoms suggestive of microvascular dysfunction. We tested the hypotheses that patients undergoing cancer treatment with 5-FU based chemotherapy regimens would present with impaired microvascular reactivity and that these findings would be substantiated by decrements in endothelial nitric oxide synthase (eNOS) gene expression in 5-FU treated human coronary artery endothelial cells (HCAEC).

Methods

We first performed a cross-sectional analysis of 30 patients undergoing 5-FU based chemotherapy treatment for cancer (5-FU) and 32 controls (CON) matched for age, sex, body mass index, and prior health history (excluding cancer). Cutaneous microvascular reactivity was evaluated by laser Doppler flowmetry in response to endothelium-dependent (local skin heating; acetylcholine iontophoresis, ACh) and -independent (sodium nitroprusside iontophoresis, SNP) stimuli. In vitro experiments in HCAEC were completed to assess the effects of 5-FU on eNOS gene expression.

Results

5-FU presented with diminished microvascular reactivity following eNOS-dependent local heating compared to CON (P = 0.001). Iontophoresis of the eNOS inhibitor L-NAME failed to alter the heating response in 5-FU (P = 0.95), despite significant reductions in CON (P = 0.03). These findings were corroborated by lower eNOS gene expression in 5-FU treated HCAEC (P < 0.01) compared to control. Peak vasodilation to ACh (P = 0.58) nor SNP (P = 0.39) were different between groups.

Conclusions

The present findings suggest diminished microvascular function along the eNOS-NO vasodilatory pathway in patients with cancer undergoing treatment with 5-FU-based chemotherapy regimens and thus, may provide insight into the underlying mechanisms of 5-FU cardiotoxicity.

A new face of old cells: An overview about the role of senescence and telomeres in inflammatory bowel diseases

Cellular senescence is a pivotal factor contributing to aging and the pathophysiology of age-related diseases. Despite the presence of inflammation and abnormal immune system function in both inflammatory bowel diseases (IBD) and senescence, the relationship between the two remains largely unexplored. Therefore, our study aimed to investigate the intricate connection between cellular senescence, telomeres, and IBD. The review highlights the presence of senescence markers, particularly p16 and p21, in IBD patients, suggesting their potential association with disease progression and mucosal inflammation. We emphasize the critical role of macrophages in eliminating senescent cells and how disturbance in effective clearance may contribute to persistent senescence and inflammation in IBD. Additionally, we shed light on the involvement of telomeres in IBD, as their dysfunction impairs enterocyte function and disrupts colonic barrier integrity, potentially exacerbating the pathogenesis of the disease. Targeting senescence and telomere dysfunctions holds promise for the development of innovative therapeutic approaches to mitigate intestinal inflammation and alleviate symptoms in IBD patients. By unraveling the precise role of senescence in IBD, we can pave the way for the discovery of novel therapeutic interventions that effectively address the underlying mechanisms of intestinal inflammation, offering hope for improved management and treatment of IBD patients.

Peficitinib ameliorates 5-fluorouracil-induced intestinal damage by inhibiting aging, inflammatory factors and oxidative stress

5-Fluorouracil (5-FU) is a conventional and effective drug for colorectal cancer patients, and it is an important part of combined chemotherapy and adjuvant chemotherapy. Chemotherapy intestinal mucositis (CIM) is a severe side effect caused by 5-FU that, induces cancer treatment failure and affects patients' quality of life. The mechanism of 5-FU-induced CIM is related to normal cell senescence induced by 5-FU. Peficitinib, a Janus Kinase (JAK) inhibitor, treats inflammatory disorders, including rheumatoid arthritis, psoriasis, and inflammatory bowel disease. However, the therapeutic role and underlying mechanism of peficitinib in CIM remain unclear. The main objective of our research was to investigate the effects of peficitinib on 5-FU-induced senescence and intestinal damage in human umbilical vein endothelial (HUVEC) cells, human intestinal epithelial (HIEC) cells and BABL/C mice. The results showed that 5-FU caused intestinal damage by inducing aging and increasing inflammation and oxidative stress. Peficitinib alleviated aging by reducing senescence-beta-galactosidase (SA-β-gal) activity and the protein levels of aging indicators (p53, p21, p16). Moreover, peficitinib reversed the changes in senescence-associated secretory phenotype (SASP) expression caused by 5-FU. Besides, 5-FU induced release of inflammatory factors and oxidative stress indicators was reversed by peficitinib. Additionally, the combination of peficitinib and 5-FU reinforced the anticancer curative intent of 5-FU in two colorectal cancer cell lines (HCT116 cells and SW620 cells). In conclusion, peficitinib alleviates mucositis by alleviating aging, reducing inflammatory accumulation and oxidative stress and enhancing the antitumor activity of 5-FU.

Atorvastatin calcium alleviates 5-fluorouracil-induced intestinal damage by inhibiting cellular senescence and significantly enhances its antitumor efficacy

5-Fluorouracil (5-Fu) is the preferred drug in colorectal cancer treatment. Although 5-Fu treatment contributes to the increase in survival rates, long-term use of 5-Fu causes severe intestinal damage, eventually decreasing long-term survival. There is no standardtreatmentfor intestinal damage induced by 5-Fu. Our previous study found that 5-Fu-induced intestinal damage was connected to an increase in senescent cells, and antiaging drugs could relieve some adverse side effects caused by 5-Fu. Hence, it is essential to discover novel, potential antiaging therapeutic drugs for 5-Fu side effect treatment. According to the current study, Atorvastatincalcium (Ator) alleviated cellular senescence in human intestinal epithelial cells (HUVECs) and human umbilical vein endothelial cells (HIECs) caused by oxidative stress and 5-Fu. 5-Fu resulted in an increase in SA-β-Gal-positive cells, synchronously increased expression of aging-related proteins (p16), aging-related genes (p53, p21), and the senescence-associated secretory phenotype (SASP: IL-1β, IL-6, TNF-α), while Atorvastatincalcium (Ator) reversed the increase in these indicators. In the BALB/c mouse model, we confirmed that intestinal damage caused by 5-Fu is related to the increase in senescent cells and drug-induced inflammation, with the therapeutic effects of Ator. In addition, Ator increased the sensitivity of 5-Fu to chemotherapy in vitro and in vivo. Combination therapy significantly reduced HCT116 cell viability. Furthermore, Ator and 5-Fu present a cooperative effect on preventing the growth of tumors in CRC xenograft nude mice. In conclusion, our study demonstrates the value of Ator for treating intestinal damage. Moreover, Ator combined with 5-Fu increased the antitumor ability in CRC cells. Additionally, we provide a novel therapeutic protocol for CRC.

An integrative review of nonobvious puzzles of cellular and molecular cardiooncology

Oncologic patients are subjected to four major treatment types: surgery, radiotherapy, chemotherapy, and immunotherapy. All nonsurgical forms of cancer management are known to potentially violate the structural and functional integrity of the cardiovascular system. The prevalence and severity of cardiotoxicity and vascular abnormalities led to the emergence of a clinical subdiscipline, called cardiooncology. This relatively new, but rapidly expanding area of knowledge, primarily focuses on clinical observations linking the adverse effects of cancer therapy with deteriorated quality of life of cancer survivors and their increased morbidity and mortality. Cellular and molecular determinants of these relations are far less understood, mainly because of several unsolved paths and contradicting findings in the literature. In this article, we provide a comprehensive view of the cellular and molecular etiology of cardiooncology. We pay particular attention to various intracellular processes that arise in cardiomyocytes, vascular endothelial cells, and smooth muscle cells treated in experimentally-controlled conditions in vitro and in vivo with ionizing radiation and drugs representing diverse modes of anti-cancer activity.

Echinacoside ameliorates 5-fluorouracil-induced endothelial injury and senescence through SIRT1 activation

Echinacoside (ECH) is a natural bioactive component with antioxidant, anti-inflammatory, anti-apoptosis, and anti-tumor properties. In the current study, we explore the ECH-mediated protective effect and underlying mechanism of 5-fluorouracil (5-FU)-induced endothelial injury and senescence in the Human umbilical vein endothelial cells (HUVECs). In HUVECs, Cell viability, Apoptosis and Senescence assays evaluated 5-fluorouracil-induced endothelial injury and senescence. Protein expressions were assessed using RT-qPCR and Western blotting. Our results showed that 5-FU-induced endothelial injury and endothelial cell senescence could be improved when treated with ECH in HUVECs. ECH treatment potentially attenuated oxidative stress and ROS production in HUVECs. In addition, the effect of ECH on autophagy markedly reduced the percentage of HUVECs with LC3-II dots and suppressed the Beclin-1 and ATG7 mRNA expression but enhanced the p62 mRNA expression. Besides, ECH treatment significantly increased migrated cells and suppressed the adhesion of THP-1 monocytes in HUVECs. Furthermore, ECH treatment activated the SIRT1 pathway, and its related proteins (SIRT1, p-AMPK and eNOS) expression increased. Nicotinamide (NAM), an inhibitor of SIRT1, significantly attenuated the ECH-induced decrease in the apoptotic rate, increased SA-β-gal-positive cells and significantly reversed the ECH-induced reduction of endothelial senescence. Our results demonstrated that ECH employed endothelial injury and senescence in HUVECs via activation of the SIRT1 pathway.

Metformin mitigates SASP secretion and LPS-triggered hyper-inflammation in Doxorubicin-induced senescent endothelial cells

Introduction: Doxorubicin (DOX), a chemotherapeutic drug, induces senescence and increases the secretion of senescence-associated secretory phenotype (SASP) in endothelial cells (ECs), which contributes to DOX-induced inflammaging. Metformin, an anti-diabetic drug, demonstrates senomorphic effects on different models of senescence. However, the effects of metformin on DOX-induced endothelial senescence have not been reported before. Senescent ECs exhibit a hyper-inflammatory response to lipopolysachharide (LPS). Therefore, in our current work, we identified the effects of metformin on DOX-induced endothelial senescence and LPS-induced hyper-inflammation in senescent ECs. Methods: ECs were treated with DOX ± metformin for 24 h followed by 72 h incubation without DOX to establish senescence. Effects of metformin on senescence markers expression, SA-β-gal activity, and SASP secretion were assessed. To delineate the molecular mechanisms, the effects of metformin on major signaling pathways were determined. The effect of LPS ± metformin was determined by stimulating both senescent and non-senescent ECs with LPS for an additional 24 h. Results: Metformin corrected DOX-induced upregulation of senescence markers and decreased the secretion of SASP factors and adhesion molecules. These effects were associated with a significant inhibition of the JNK and NF-κB pathway. A significant hyper-inflammatory response to LPS was observed in DOX-induced senescent ECs compared to non-senescent ECs. Metformin blunted LPS-induced upregulation of pro-inflammatory SASP factors. Conclusion: Our study demonstrates that metformin mitigates DOX-induced endothelial senescence phenotype and ameliorates the hyper-inflammatory response to LPS. These findings suggest that metformin may protect against DOX-induced vascular aging and endothelial dysfunction and ameliorate infection-induced hyper-inflammation in DOX-treated cancer survivors.

Therapeutic opportunities for senolysis in cardiovascular disease

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

Inside the Mechanism of Action of Three Pyrazole Derivatives in Human Platelets and Endothelial Cells

In the effort to obtain multitarget compound interfering with inflammation, oxidative stress, and tumorigenesis, we synthesized a small library of pyrazole compounds, selecting 4a, 4f, and 4g as the most noteworthy being IC₅₀ against platelet ROS production induced by thrombin of about 10 µM. The in vitro antioxidant potential of the three molecules was evaluated, and since they show a remarkable antioxidative activity, their effect on several parameter indicative of oxidative status and on the efficiency of the aerobic metabolism was tested. The three molecules strongly inhibit superoxide anion production, lipid peroxidation, NADPH oxidase activity and almost restore the oxidative phosphorylation efficiency in thrombin-stimulated platelet, demonstrating a protective effect against oxidative stress. This effect was confirmed in endothelial cell in which 4a, 4f, and 4g show an interesting inhibition activity on H₂O₂-stimulated EA.hy926 cells. At last, antiproliferative activity of 4a, 4f, and 4g was submitted to a large screening at the NCI. The molecules show interesting anticancer activity, among them the most remarkable is 4g able to strongly inhibit the proliferation of both solid tumor and leukemia cells lines. In conclusion, all the three newly synthetized pyrazoles show remarkable antioxidant and antiproliferative effect worthy of further study.

Endogenous Vasoactive Peptides and Vascular Aging-Related Diseases

Vascular aging is a specific type of organic aging that plays a central role in the morbidity and mortality of cardiovascular and cerebrovascular diseases among the elderly. It is essential to develop novel interventions to prevent/delay age-related vascular pathologies by targeting fundamental cellular and molecular aging processes. Endogenous vasoactive peptides are compounds formed by a group of amino acids connected by peptide chains that exert regulatory roles in intercellular interactions involved in a variety of biological and pathological processes. Emerging evidence suggests that a variety of vasoactive peptides play important roles in the occurrence and development of vascular aging and related diseases such as atherosclerosis, hypertension, vascular calcification, abdominal aortic aneurysms, and stroke. This review will summarize the cumulative roles and mechanisms of several important endogenous vasoactive peptides in vascular aging and vascular aging-related diseases. In addition, we also aim to explore the promising diagnostic function as biomarkers and the potential therapeutic application of endogenous vasoactive peptides in vascular aging-related diseases.

Serum levels of VCAM-1 are associated with survival in patients treated with nivolumab for NSCLC

BACKGROUND

High circulating levels of cellular adhesion molecules (CAMs) in non-small cell lung cancer (NSCLC) have been supposed to act as a negative prognostic factor. Here, we explored the predictive role of pre-treatment levels of CAMs in previously treated patients receiving nivolumab for NSCLC.

MATERIALS AND METHODS

Seventy one patients with advanced NSCLC, treated with nivolumab at the dose of 3 mg/kg every 14 days, were enrolled. Maximum follow-up time was 3 years. Serum levels of Vascular Cell Adhesion Molecule-1 (VCAM-1) and Intracellular Adhesion Molecule-1 (ICAM-1) were measured at baseline and before each nivolumab administration. Endpoints of the study were a composite outcome of survival ≥2 years or absence of disease progression at the end of the follow-up, and the overall survival.

RESULTS

Composite outcome and overall survival were positively associated with VCAM-1 baseline levels and with the reduction of VCAM-1 during the treatment. After adjustment for potential confounders, the change in VCAM-1 serum levels during the treatment was an independent predictor of overall survival.

CONCLUSIONS

High baseline serum levels of VCAM-1 are associated with a longer survival in patients treated with nivolumab as second line treatment for NSCLC. Surviving patients experience also a significant reduction in CAMs expression during the treatment. Hence, CAMs might be promising prognostic factors in patients with NSCLC underoing immunotherapy.

Breast cancer chemotherapy vascular toxicity: a review of mediating mechanisms and exercise as a potential therapeutic

Breast cancer chemotherapy, although very potent against tumour tissue, results in significant cardiovascular toxicity. The focus of research in this area has been predominantly towards cardiotoxicity. There is limited evidence detailing the impact of such treatment on the vasculature despite its central importance within the cardiovascular system and resultant detrimental effects of damage and dysfunction. This review highlights the impact of chemotherapy for breast cancer on the vascular endothelium. We consider the most likely mechanisms of endothelial toxicity to be through direct damage and dysfunction of the endothelium. There are sharp consequences of these detrimental effects as they can lead to cardiovascular disease. However, there is potential for exercise to alleviate some of the vascular toxicity of chemotherapy, and the evidence for this is provided. The potential role of exercise in protecting against vascular toxicity is explained, highlighting the recent in-human and animal model exercise interventions. Lastly, the mediating mechanisms of exercise protection of endothelial health is discussed, focusing on the importance of exercise for endothelial health, function, repair, inflammation and hyperlipidaemia, angiogenesis, and vascular remodelling. These are all important counteracting measures against chemotherapy-induced toxicity and are discussed in detail.

Cardiotoxicity of Fluoropyrimidines: Epidemiology, Mechanisms, Diagnosis, and Management

Cancer is a growing public health problem; it is responsible annually for millions of deaths worldwide. Fluoropyrimidines are highly effective and commonly prescribed anti-neoplastic drugs used in a wide range of chemotherapy regimens against several types of malignancies. 5-fluorouracil and its prodrugs affect neoplastic cells in multiple ways by impairing their proliferation, principally through the inhibition of thymidylate synthase. Fluoropyrimidine-induced cardiotoxicity was described more than 50 years ago, but many details such as incidence, mechanisms, and treatment are unclear and remain disputed. Severe cardiotoxicity is not only life-threatening, but also leads to withdrawal from an optimal chemotherapy regimen and decreases survival rate. Differences in the frequency of cardiotoxicity are explained by different chemotherapy schedules, doses, criteria, and populations. Proposed pathophysiological mechanisms include coronary vasospasm, endothelial damage, oxidative stress, Krebs cycle disturbances, and toxic metabolites. Such varied pathophysiology of the cardiotoxicity phenomenon makes prevention and treatment more difficult. Cardiovascular disturbances, including chest pain, arrhythmias, and myocardial infarction, are among the most common side effects of this class of anti-neoplastic medication. This study aims to summarize the available data on fluoropyrimidine cardiotoxicity with respect to symptoms, incidence, metabolism, pathophysiological mechanism, diagnosis, management, and resistance.

Omarigliptin Prevents TNF-α-Induced Cellular Senescence in Rat Aorta Vascular Smooth Muscle Cells

Cellular senescence is one of the most significant factors involved in aging and age-related diseases. Senescence of vascular smooth muscle cells (VSMCs) adversely affects the function of the cardiovascular system and contributes to the development of atherosclerosis, hypertension, and other cardiovascular diseases. Glucagon-like peptide-1 (GLP-1) is an important incretin hormone involved in insulin release and vascular tone. GLP-1 is quickly degraded by the enzyme dipeptidyl peptidase-4 (DPP-4). Omarigliptin is a new DPP-4 inhibitor that has demonstrated anti-inflammatory and antioxidative stress properties. In the present study, we investigated the effects of the selective DPP-4 inhibitor omarigliptin (OMG) on VSMCs exposed to insult from tumor necrosis factor-α (TNF-α), one of the main inflammatory signaling molecules involved in cellular senescence. We found that OMG could suppress TNF-α-induced expression of pro-inflammatory cytokines (interleukin-1β (IL-1β), IL-6, and IL-8) and inhibit oxidative stress by reducing the production of H2O2 and protein carbonyl. OMG ameliorated the increase in senescence-associated β-galactosidase (SA-β-gal) and telomerase activity induced by TNF-α. The plasminogen activator inhibitor-1 (PAI-1)/p53/p21 pathway is a key inducer of cellular senescence. OMG ameliorated the acetylation of p53 at lysine 382 (K382) and subsequent activation of p21 via inhibition of PAI-1. Importantly, our experiments revealed that blockage of silent information-regulator 1 (SIRT1) abolished the inhibitory effects of OMG on p53 acetylation, SA-β-gal activity, and telomerase activity in VSMCs. These results suggest that OMG may have the potential to delay or prevent the progression of age-related cardiovascular diseases by modulating the activity of SIRT1.

Metformin inhibits cholesterol‑induced adhesion molecule expression via activating the AMPK signaling pathway in vascular smooth muscle cells

Recruitment of lymphocytes to the vascular wall contributes to the pathogenesis of atherosclerosis (AS). The expression of cellular adhesion molecules, such as vascular cell adhesion molecule-1 and intercellular adhesion molecule-1, serves a critical role in mediating lymphocyte adhesion to the vascular wall. Cholesterol loading induces the expression of adhesion molecules in vascular smooth muscle cells (VSMCs), but the underlying mechanism is not completely understood. The present study aimed to investigate the mechanism underlying the effects of cholesterol on adhesion molecule expression, and whether metformin protected VSMCs against cholesterol-induced functional alterations. Human VSMCs were loaded with cholesterol and different concentrations of metformin. The expression levels of adhesion molecules were assessed via reverse transcription-quantitative PCR and western blotting. Reactive oxygen species (ROS) accumulation and levels were quantified via fluorescence assays and spectrophotometry, respectively. AMP-activated protein kinase (AMPK), p38 MAPK and NF-κB signaling pathway-related protein expression levels were evaluated via western blotting. Compared with the control group, cholesterol loading significantly upregulated adhesion molecule expression levels on VSMCs by increasing intracellular ROS levels and activating the p38 MAPK and NF-κB signaling pathways. Metformin decreased cholesterol-induced VSMC damage by activating the AMPK signaling pathway, and suppressing p38 MAPK and NF-κB signaling. The present study indicated the therapeutic potential of metformin for VSMC protection, reduction of monocyte adhesion, and ultimately, the prevention and treatment of AS.

Molecular mechanisms and cardiovascular implications of cancer therapy-induced senescence

Cancer treatment has been associated with accelerated aging that can lead to early-onset health complications typically experienced by older populations. In particular, cancer survivors have an increased risk of developing premature cardiovascular complications. In the last two decades, cellular senescence has been proposed as an important mechanism of premature cardiovascular diseases. Cancer treatments, specifically anthracyclines and radiation, have been shown to induce senescence in different types of cardiovascular cells. Additionally, clinical studies identified increased systemic markers of senescence in cancer survivors. Preclinical research has demonstrated the potential of several approaches to mitigate cancer therapy-induced senescence. However, strategies to prevent and/or treat therapy-induced cardiovascular senescence have not yet been translated to the clinic. In this review, we will discuss how therapy-induced senescence can contribute to cardiovascular complications. Thereafter, we will summarize the current in vitro, in vivo, and clinical evidence regarding cancer therapy-induced cardiovascular senescence. Then, we will discuss interventional strategies that have the potential to protect against therapy-induced cardiovascular senescence. To conclude, we will highlight challenges and future research directions to mitigate therapy-induced cardiovascular senescence in cancer survivors.

Antioxidant Approach as a Cardioprotective Strategy in Chemotherapy-Induced Cardiotoxicity

Significance: Chemotherapy-induced cardiotoxicity (CTX) has been associated with redox signaling imbalance. In fact, redox reactions are crucial for normal heart physiology, whereas excessive oxidative stress can cause cardiomyocyte structural damage. Recent Advances: An antioxidant approach as a cardioprotective strategy in this setting has shown encouraging results in preventing anticancer drug-induced CTX. Critical Issues: In fact, traditional heart failure drugs as well as many other compounds and nonpharmacological strategies, with a partial effect in reducing oxidative stress, have been shown to counterbalance chemotherapy-induced CTX in this setting to some extent. Future Directions: Given the various pathways of toxicity involved in different chemotherapeutic schemes, interactions with redox balance need to be fine-tuned and a personalized cardioprotective approach seems to be required.

Cancer Therapy-Associated Thrombosis

[Figure: see text].

Tolerance develops toward GLP-1 receptor agonists' glucose-lowering effect in mice

Glucagon-like peptide 1 (GLP-1) receptor agonists are popular antidiabetic drugs with potent glucose-lowering effects and low risk of hypoglycemia. Animal experiments and human data indicate that tolerance develops toward at least some of their effects, e.g., gastric motility. Whether tolerance develops toward the glucose-lowering effect of GLP-1 receptor agonists in mice has never been formally tested. The hypothesis of tolerance development in mice will be reported in this study. The direct glucose-lowering effect of the GLP-1 receptor agonists was measured in non-fasted mice and with intraperitoneal glucose tolerance test. Exenatide (10 μg/kg) and liraglutide (600 μg/kg) both substantially lost efficacy during the 18-day treatment as compared to the acute effect. We conclude that our results demonstrate development of tolerance toward GLP-1 receptor agonists' glucose-lowering effect in mice.

Cardiotoxicities of 5-Fluorouracil and Other Fluoropyrimidines

OPINION STATEMENT

Fluoropyrimidine (FP) is used to treat a wide range of cancers; however, it is associated with drug-induced vascular toxicity, as well as angina pectoris and coronary spasm. FP has been administered for many years, although the incidence, mechanisms, and appropriate methods for managing its associated cardiovascular toxicities have not been clarified, and the management of these complications has not been standardized. This lack of evidence is not limited to FP. Many trials of anticancer agents have been conducted, excluding patients with heart diseases. Hence, there is a paucity of epidemiological data on cardiovascular adverse events caused by anticancer agents. There have been remarkable improvements in cancer treatment in recent years, with consequent improvements in prognosis. In this context, new cardiovascular toxicities related to new drugs have emerged. We are now compelled to respond to cardiovascular adverse events despite the lack of evidence regarding optimal management. The result has been establishment and rapid maturation of the new academic field of cardio-oncology. Despite the relative lack of evidence, we must review small pieces of evidence that have accumulated to date and make the utmost efforts to provide patients with effective evidence-based medical care. Simultaneously, we urgently need randomized clinical trials to build strong evidence.

CO ameliorates endothelial senescence induced by 5-fluorouracil through SIRT1 activation

Endothelial senescence is the main risk factor that contributes to vascular dysfunction and the progression of vascular disease. Carbon monoxide (CO) plays an important role in preventing vascular dysfunction and in maintaining vascular physiology or homeostasis. The application of exogenous CO has been shown to confer protection in several models of cardiovascular injury or disease, including hypertension, atherosclerosis, balloon-catheter injury, and graft rejection. However, the mechanism by which CO prevents endothelial senescence has been largely unexplored. The aim of this study was to evaluate the effects of CO on endothelial senescence and to investigate the possible mechanisms underlying this process. We measured the levels of senescence-associated-β-galactosidase activity, senescence-associated secretory phenotype, reactive oxygen species (ROS) production, and stress granule in human umbilical vein endothelial cells and the WI-38 human diploid fibroblast cell line. We found that 5-fluorouracil (5FU)-induced ROS generation was inhibited by CO-releasing molecules (CORM)-A1 treatment, and endothelial senescence induced by 5FU was attenuated by CORM-A1 treatment. The SIRT1 inhibitor EX527 reversed the inhibitory effect of CO on the 5FU-induced endothelial senescence. Furthermore, SIRT1 deficiency abolished the stress granule formation by CO. Our results suggest that CO alleviates the endothelial senescence induced by 5FU through SIRT1 activation and may hence have therapeutic potential for the treatment of vascular diseases.

Abemaciclib Is Effective Against Pancreatic Cancer Cells and Synergizes with HuR and YAP1 Inhibition

Mutation or promoter hypermethylation of CDKN2A is found in over 90% of pancreatic ductal adenocarcinomas (PDAC) and leads to loss of function of cell-cycle inhibitors p16 (INK4A) and p14 (ARF) resulting in unchecked proliferation. The CDK4/6 inhibitor, abemaciclib, has nanomolar IC₅₀s in PDAC cell lines and decreases growth through inhibition of phospho-Rb (pRb), G₁ cell-cycle arrest, apoptosis, and the senescent phenotype detected with β-galactosidase staining and relevant mRNA elevations. Daily abemaciclib treatments in mouse PDAC xenograft studies were safe and demonstrated a 3.2-fold decrease in tumor volume compared with no treatment (P < 0.0001) accompanying a decrease in both pRb and Ki67. We determined that inhibitors of HuR (ELAVL1), a prosurvival mRNA stability factor that regulates cyclin D1, and an inhibitor of Yes-Associated Protein 1 (YAP1), a pro-oncogenic, transcriptional coactivator important for CDK6 and cyclin D1, were both synergistic with abemaciclib. Accordingly, siRNA oligonucleotides targeted against HuR, YAP1, and their common target cyclin D1, validated the synergy studies. In addition, we have seen increased sensitivity to abemaciclib in a PDAC cell line that harbors a loss of the ELAVL1 gene via CRISP-Cas9 technology. As an in vitro model for resistance, we investigated the effects of long-term abemaciclib exposure. PDAC cells chronically cultured with abemaciclib displayed a reduction in cellular growth rates (GR) and coresistance to gemcitabine and 5-fluorouracil (5-FU), but not to HuR or YAP1 inhibitors as compared with no treatment controls. We believe that our data provide compelling preclinical evidence for an abemaciclib combination-based clinical trial in patients with PDAC. IMPLICATIONS: Our data suggest that abemaciclib may be therapeutically relevant for the treatment in PDAC, especially as part of a combination regimen inhibiting YAP1 or HuR.

The Post-amyloid Era in Alzheimer's Disease: Trust Your Gut Feeling

The amyloid hypothesis, the assumption that beta-amyloid toxicity is the primary cause of neuronal and synaptic loss, has been the mainstream research concept in Alzheimer's disease for the past two decades. Currently, this model is quietly being replaced by a more holistic, “systemic disease” paradigm which, like the aging process, affects multiple body tissues and organs, including the gut microbiota. It is well-established that inflammation is a hallmark of cellular senescence; however, the infection-senescence link has been less explored. Microbiota-induced senescence is a gradually emerging concept promoted by the discovery of pathogens and their products in Alzheimer's disease brains associated with senescent neurons, glia, and endothelial cells. Infectious agents have previously been associated with Alzheimer's disease, but the cause vs. effect issue could not be resolved. A recent study may have settled this debate as it shows that gingipain, a Porphyromonas gingivalis toxin, can be detected not only in Alzheimer's disease but also in the brains of older individuals deceased prior to developing the illness. In this review, we take the position that gut and other microbes from the body periphery reach the brain by triggering intestinal and blood-brain barrier senescence and disruption. We also surmise that novel Alzheimer's disease findings, including neuronal somatic mosaicism, iron dyshomeostasis, aggressive glial phenotypes, and loss of aerobic glycolysis, can be explained by the infection-senescence model. In addition, we discuss potential cellular senescence targets and therapeutic strategies, including iron chelators, inflammasome inhibitors, senolytic antibiotics, mitophagy inducers, and epigenetic metabolic reprograming.

Targeting pro-senescence mitogen activated protein kinase (Mapk) enzymes with bioactive natural compounds

Aging is a multifactorial universal process characterized by a gradual decrease in physiological and biochemical functions. Given that life expectancy is on the rise, a better understanding of molecular mechanisms of the aging process is necessary in order to develop anti-aging interventions. Uncontrolled cellular senescence promotes persistent inflammation and accelerates the aging process by decreasing tissue renewal, repair and regeneration. Senescence of immune cells, immunesenescence, is another hallmark of aging. Targeting pro-senescent enzymes increases survival and therefore the lifespan. Although the upregulation of Mitogen Activated Protein Kinases (MAPK) enzymes in aging is still controversial, increasing evidence shows that dysregulation of those enzymes are associated with biological processes that contribute to aging such as irreversible senescence. In this manuscript components of the MAPK pathway will be summarized, including extracellular signal-regulated kinase 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK) and p38, as well as natural flavonoids, phenolic and diterpenoids with anti-senescence activity that shows positive effects on longevity and MAPK inhibition. Although more studies using additional aging models are needed, we suggest that these selected natural bioactive compounds that regulate MAPK enzymes and reduce senescent cells can be potentially used to improve longevity and prevent/treat age-related diseases.

Coronary Artery Vasospasm Induced by 5-fluorouracil: Proposed Mechanisms, Existing Management Options and Future Directions

Cardiovascular disease and cancer are leading contributors to the global disease burden. As a result of cancer therapy-related cardiotoxicities, cardiovascular disease results in significant morbidity and mortality in cancer survivors and patients with active cancer. There is an unmet need for management of cardio-oncology conditions, which is predicted to reach epidemic proportions, and better understanding of their pathophysiology and treatment is urgently required. The proposed mechanisms underlying cardiotoxicity induced by 5-fluorouracil (5-FU) are vascular endothelial damage followed by thrombus formation, ischaemia secondary to coronary artery vasospasm, direct toxicity on myocardium and thrombogenicity. In patients with angina and electrocardiographic evidence of myocardial ischaemia due to chemotherapy-related coronary artery vasospasm, termination of chemotherapy and administration of calcium channel blockers or nitrates can improve ischaemic symptoms. However, coronary artery vasospasm can reoccur with 5-FU re-administration with limited effectiveness of vasodilator prophylaxis observed. While pre-existing coronary artery disease may increase the ischaemic potential of 5-FU, cardiovascular risk factors do not appear to completely predict the development of cardiac complications. Pharmacogenomic studies and genetic profiling may help predict the occurrence and streamline the treatment of 5-FU-induced coronary artery vasospasm. Echocardiographic measures such as the Tei index may help detect subclinical 5-FU cardiotoxicity. Further research is required to explore the cardioprotective effect of agents such as coenzyme complex, GLP-1 analogues and degradation inhibitors on 5-FU-induced coronary artery vasospasm.

Data regarding the effects of thrombin and dabigatran-inhibited thrombin on protease-activated receptor 1 and activation of human atrial fibroblasts

The data presented here are related to the research paper entitled "Thrombin induces protease-activated receptor 1 signaling and activation of human atrial fibroblasts and dabigatran prevents these effects" (Altieri et al., 2018) [1]. Data show that silencing of protease-activated receptor 1 (PAR1) prevents the activation of Fib isolated from atrial appendages of patients without atrial fibrillation (AF), as assessed by immunofluorescence for α-smooth muscle actin (αSMA) and Picro-Sirius red staining. Moreover, it is reported that primary atrial Fib obtained from two subjects with permanent AF express PAR1 and PAR2 and display enhanced αSMA immunoreactivity and collagen synthesis in response to thrombin, but not to dabigatran-bound thrombin, alike Fib from non-fibrillating atria.

Antineoplastic Drug-Induced Cardiotoxicity: A Redox Perspective

Antineoplastic drugs can be associated with several side effects, including cardiovascular toxicity (CTX). Biochemical studies have identified multiple mechanisms of CTX. Chemoterapeutic agents can alter redox homeostasis by increasing the production of reactive oxygen species (ROS) and reactive nitrogen species RNS. Cellular sources of ROS/RNS are cardiomyocytes, endothelial cells, stromal and inflammatory cells in the heart. Mitochondria, peroxisomes and other subcellular components are central hubs that control redox homeostasis. Mitochondria are central targets for antineoplastic drug-induced CTX. Understanding the mechanisms of CTX is fundamental for effective cardioprotection, without compromising the efficacy of anticancer treatments. Type 1 CTX is associated with irreversible cardiac cell injury and is typically caused by anthracyclines and conventional chemotherapeutic agents. Type 2 CTX, associated with reversible myocardial dysfunction, is generally caused by biologicals and targeted drugs. Although oxidative/nitrosative reactions play a central role in CTX caused by different antineoplastic drugs, additional mechanisms involving directly and indirectly cardiomyocytes and inflammatory cells play a role in cardiovascular toxicities. Identification of cardiologic risk factors and an integrated approach using molecular, imaging, and clinical data may allow the selection of patients at risk of developing chemotherapy-related CTX. Although the last decade has witnessed intense research related to the molecular and biochemical mechanisms of CTX of antineoplastic drugs, experimental and clinical studies are urgently needed to balance safety and efficacy of novel cancer therapies.

Fluoropyrimidine-induced cardiotoxicity

Fluoropyrimidines (5-fluorouracil and capecitabine) are antimetabolite drugs, widely used for the treatment of a variety of cancers, both in adjuvant and in metastatic setting. Although the most common toxicities of these drugs have been extensively studied, robust data and comprehensive characterization still lack concerning fluoropyrimidine-induced cardiotoxicity (FIC), an infrequent but potentially life-threatening toxicity. This review summarizes the current state of knowledge of FIC with special regard to proposed pathogenetic models (coronary vasospasm, endothelium and cardiomyocytes damage, toxic metabolites, dihydropyrimidine dehydrogenase deficiency); risk and predictive factors; efficacy and usefulness in detection of laboratory markers, electrocardiographic changes and cardiac imaging; and specific treatment, including a novel agent, uridine triacetate. The role of alternative chemotherapeutic options, namely raltitrexed and TAS-102, is discussed, and, lastly, we overview the most promising future directions in the research on FIC and development of diagnostic tools, including microRNA technology.

5-fluorouracil causes endothelial cell senescence: potential protective role of glucagon-like peptide 1

BACKGROUND AND PURPOSE

5-fluorouracil (5FU) and its prodrug, capecitabine, can damage endothelial cells, whilst endothelial integrity is preserved by glucagon-like peptide 1 (GLP-1). Here, we studied the effect of 5FU on endothelial senescence and whether GLP-1 antagonizes it.

EXPERIMENTAL APPROACH

EA.hy926 cells were exposed to 5FU or sera from patients taking capecitabine, with or without pre-incubation with GLP-1. Senescence was identified by expression of senescence-associated β-galactosidase and p16INK4a and reduced cell proliferation. Soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and CD146 (marker of endothelial injury) were measured by ELISA before and at completion of capecitabine chemotherapy. RT-PCR, western blotting, functional experiments with signalling inhibitors and ERK1/2 silencing were performed to characterize 5FU-induced phenotype and elucidate the pathways underlying 5FU and GLP-1 activity.

KEY RESULTS

Both 5FU and sera from capecitabine-treated patients stimulated endothelial cell senescence. 5FU-elicited senescence occurred via activation of p38 and JNK, and was associated with decreased eNOS and SIRT-1 levels. Furthermore, 5FU up-regulated VCAM1 and TYMP (encodes enzyme activating capecitabine and 5FU), and sVCAM-1 and CD146 concentrations were higher after than before capecitabine chemotherapy. A non-significant trend for higher ICAM1 levels was also observed. GLP-1 counteracted 5FU-initiated senescence and reduced eNOS and SIRT-1 expression, this protection being mediated by GLP-1 receptor, ERK1/2 and, possibly, PKA and PI3K.

CONCLUSIONS AND IMPLICATIONS

5FU causes endothelial cell senescence and dysfunction, which may contribute to its cardiovascular side effects. 5FU-triggered senescence was prevented by GLP-1, raising the possibility of using GLP-1 analogues and degradation inhibitors to treat 5FU and capecitabine vascular toxicity.

LINKED ARTICLES

This article is part of a themed section on New Insights into Cardiotoxicity Caused by Chemotherapeutic Agents. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.21/issuetoc.

Angelica sinensis Polysaccharides Ameliorate Stress-Induced Premature Senescence of Hematopoietic Cell via Protecting Bone Marrow Stromal Cells from Oxidative Injuries Caused by 5-Fluorouracil

Myelosuppression is the most common complication of chemotherapy. Decline of self-renewal capacity and stress-induced premature senescence (SIPS) of hematopoietic stem cells (HSCs) induced by chemotherapeutic agents may be the cause of long-term myelosuppression after chemotherapy. Whether the mechanism of SIPS of hematopoietic cells relates to chemotherapeutic injury occurred in hematopoietic microenvironment (HM) is still not well elucidated. This study explored the protective effect of Angelica sinensis polysaccharide (ASP), an acetone extract polysaccharide found as the major effective ingredients of a traditional Chinese medicinal herb named Chinese Angelica (Dong Quai), on oxidative damage of homo sapiens bone marrow/stroma cell line (HS-5) caused by 5-fluorouracil (5-FU), and the effect of ASP relieving oxidative stress in HM on SIPS of hematopoietic cells. Tumor-suppressive doses of 5-FU inhibited the growth of HS-5 in a dose-dependent and time-dependent manner. 5-FU induced HS-5 apoptosis and also accumulated cellular hallmarks of senescence including cell cycle arrest and typical senescence-associated β-galactosidase positive staining. The intracellular reactive oxygen species (ROS) was increased in 5-FU treated HS-5 cells and coinstantaneous with attenuated antioxidant capacity marked by superoxide dismutase and glutathione peroxidase. Oxidative stress initiated DNA damage indicated by increased γH2AX and 8-OHdG. Oxidative damage of HS-5 cells resulted in declined hematopoietic stimulating factors including stem cell factor (SCF), stromal cell-derived factor (SDF), and granulocyte-macrophage colony-stimulating factor (GM-CSF), however, elevated inflammatory chemokines such as RANTES. In addition, gap junction channel protein expression and mediated intercellular communications were attenuated after 5-FU treatment. Significantly, co-culture on 5-FU treated HS-5 feeder layer resulted in less quantity of human umbilical cord blood-derived hematopoietic cells and CD34⁺ hematopoietic stem/progenitor cells (HSPCs), and SIPS of hematopoietic cells. However, it is noteworthy that ASP ameliorated SIPS of hematopoietic cells by the mechanism of protecting bone marrow stromal cells from chemotherapeutic injury via mitigating oxidative damage of stromal cells and improving their hematopoietic function. This study provides a new strategy to alleviate the complication of conventional cancer therapy using chemotherapeutic agents.

New insights into cardiotoxicity caused by chemotherapeutic agents

LINKED ARTICLES

This article is part of a themed section on New Insights into Cardiotoxicity Caused by Chemotherapeutic Agents. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.21/issuetoc.