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Cellular senescence is a stress response elicited by different molecular insults. Senescence results in cell cycle exit and is characterised by multiple phenotypic changes such as the production of a bioactive secretome. Senescent cells accumulate during ageing and are present in cancerous and fibrotic lesions. Drugs that selectively kill senescent cells (senolytics) have shown great promise for the treatment of age-related diseases. Senescence plays paradoxical roles in cancer. Induction of senescence limits cancer progression and contributes to therapy success, but lingering senescent cells fuel progression, recurrence, and metastasis. In this review, we describe the intricate relation between senescence and cancer. Moreover, we enumerate how current anti-cancer therapies induce senescence in tumour cells and how senolytic agents could be deployed to complement anticancer therapies. "One-two punch" therapies aim to first induce senescence in the tumour followed by senolytic treatment to target newly exposed vulnerabilities in senescent tumour cells. "One-two punch" represents an emerging and promising new strategy in cancer treatment. Future challenges of "one -two punch" approaches include how to best monitor senescence in cancer patients to effectively survey their efficacy.

Cellular senescence is a stress response involved in ageing and diverse disease processes including cancer, type-2 diabetes, osteoarthritis and viral infection. Despite growing interest in targeted elimination of senescent cells, only few senolytics are known due to the lack of well-characterized molecular targets. Here, we report the discovery of three senolytics using cost-effective machine learning algorithms trained solely on published data. We computationally screened various chemical libraries and validated the senolytic action of ginkgetin, periplocin and oleandrin in human cell lines under various modalities of senescence. The compounds have potency comparable to known senolytics, and we show that oleandrin has improved potency over its target as compared to best-in-class alternatives. Our approach led to several hundred-fold reduction in drug screening costs and demonstrates that artificial intelligence can take maximum advantage of small and heterogeneous drug screening data, paving the way for new open science approaches to early-stage drug discovery.

Purpose of review Cellular senescence has been recognized as a promising target in the treatment of many cardiovascular diseases. The pathways involved in the development of senescence share many similarities with pathobiological mechanisms of pulmonary arterial hypertension (PAH). But the potential of senolytics to improve pulmonary hemodynamics and to reduce vascular remodelling in PAH has thus far not been investigated in depth. Recent findings PAH does not seem to be a disease of only young people since the mean age of PAH patients is constantly increasing. Changes in expression of senescence biomarkers related to cell cycle arrest, namely upregulation of the tumour suppressor protein p53 and the cell cycle inhibitors p16(ink4A) an p21(cip1) as well as an increase in apoptosis resistance biomarker Bcl2 (B-cell lymphoma 2) and development of senescence-associated phenotype characterized by excessive production of matrix metalloproteinase 2 and interleukin 6 were demonstrated in PAH patients. Initiatives to link the senescence-modulating effect of certain compounds to clinically relevant outcomes in PAH are still limited. Further exploration of the role of senescence in the pathobiology of PAH may point to new relevant treatment strategies. Identification of the cell-specific senescence biomarkers which can be used in vivo, could further promote identification of clinically relevant pathways and design of clinical studies which will help to establish effective therapeutic use of senolytic compounds.

Purpose of review Drug use in elderly people is high compared to younger people. Simultaneously, elderly are at greater risk when exposed to environmental substances. It is puzzling therefore, that ageing, as a variable in pharmacological and toxicological processes is not investigated in more depth. Moreover, recent data suggest that molecular manifestations of the ageing process also hallmark the pathogenesis of chronic lung diseases, which may impact pharmacology and toxicology. Recent findings In particular, absorption, distribution, metabolism and excretion (ADME) processes of drugs and toxins alter because of ageing. Polypharmacy, which is quite usual with increasing age, increases the risk of drug-drug interactions. Individual differences in combination of drugs use in conjunction with individual variations in drug metabolizing enzymes can influence lung function. Exploring exposure throughout life (i.e. during ageing) to potential triggers, including polypharmacy, may avoid lung disease or unexplained cases of lung damage. Understanding of the ageing process further unravels critical features of chronic lung disease and helps to define new protective targets and therapies. Optimizing resilience can be key in pharmacology and toxicology and helps in maintaining healthy lungs for a longer period.

The enormous societal impact of the ongoing COVID-19 pandemic has been particularly harsh for some social groups, such as the elderly. Recently, it has been suggested that senescent cells could play a central role in pathogenesis by exacerbating the pro-inflammatory immune response against SARS-CoV-2. Therefore, the selective clearance of senescent cells by senolytic drugs may be useful as a therapy to ameliorate the symptoms of COVID-19 in some cases. Using the established COVID-19 murine model K18-hACE2, we demonstrated that a combination of the senolytics dasatinib and quercetin (D/Q) significantly reduced SARS-CoV-2-related mortality, delayed its onset, and reduced the number of other clinical symptoms. The increase in senescent markers that we detected in the lungs in response to SARS-CoV-2 may be related to the post-COVID-19 sequelae described to date. These results place senescent cells as central targets for the treatment of COVID-19, and make D/Q a new and promising therapeutic tool., This work was supported by grants from the Instituto de Salud Carlos III (ISCIII), COV20-00755 (C.V.K.) and COV20-00792 (M.B., M.A.R.), Apadrina la Ciencia (C.S., C.O., G.G.A.), the AECC Scientific Foundation, PRDMA18011PAST, SIRTBIO- LABAE18008FERN (P.J.F.M., A.P., A.S.R.), the RETOS projects Programme of Ministerio de Ciencia e Innovación (MICINN), SAF2017-85766-R and PID2020-114077RB-I00 (P.J.F.M., A.P., A.S.R.), Ramon y Cajal Award from MICINN, RYC-2017-22335 (P.J.F.M., A.P., A.S.R.), Proyecto REACT from REACT/European Union/FEDER, COVTRAVI-19-CM U (J.M.S., M.F., N.G.), grant from Consejo Superior de Investigaciones Científicas (CSIC), CSIC-COV19-014 (A.I.d.Á), PID2020-113888RB-I00 from MICINN (A.I.d.Á), and the European Commission–Next Generation EU (regulation EU 2020/2094), through the CSIC's Global Health Platform (PTI+ Global Health) (A.I.d.Á). The RT–qPCR reactions were provided by the Genomics and NGS Core Facility (GENGS) at the Centro de Biología Molecular Severo Ochoa (CBMSO, CSIC-UAM) Madrid, Spain, which obtains general funding from both institutions. The GENGS facility is part of the PTI+ Global Health (CSIC) (http://www.cbm.uam.es/genomica).

As humans age, their immune system undergoes modifications, including a low-grade inflammatory status called inflammaging. These changes are associated with a loss of physical and immune resilience, amplifying the risk of being malnourished and frail. Under the COVID-19 scenario, inflammaging increases the susceptibility to poor prognostics. We aimed to bring the current concepts of inflammaging and its relationship with frailty and COVID-19 prognostic; highlight the importance of evaluating the nutritional risk together with frailty aiming to monitor older adults in COVID-19 scenario; explore some compounds with potential to modulate inflammaging in perspective to manage the COVID-19 infection. Substances such as probiotics and senolytics can help reduce the high inflammatory status. Also, the periodic evaluation of nutrition risk and frailty will allow interventions, assuring the appropriate care.

Staranje je poglavitni dejavnik tveganja za razvoj številnih, s starostjo povezanih bolezni, kot so demenca, hipertenzija, ateroskleroza, rak, avtoimunske in druge bolezni. Mnoge raziskave dokazujejo, da staranje ni programiran proces in da bi nanj, posledično tudi na s starostjo povezane bolezni, lahko vplivali z zunanjimi terapevtskimi pristopi. Eden takšnih je modulacija ali odstranjevanje senescentnih celic, ki se kot odziv na različne stresorje ustavijo v fazi G1 ali G2 celičnega cikla, izrazijo svoj specifični fenotip ter se s starostjo začnejo kopičiti v organizmu. Področje celične senescence je dokaj novo področje raziskav, zato ostajajo odprta še številna vprašanja, tako glede mehanizma nastanka kot razlogov za kopičenje senescentnih celic v poznejših letih. Navkljub tem izzivom že poteka intenziven razvoj spojin s terapevtskim učinkom prek delovanja na senescenco, t. i. senoterapevtikov, saj je povečana količina teh celic povezana z razvojem s starostjo povezanih bolezni. Spojine delimo v dve glavni skupini: na senomorfike, s katerimi moduliramo nekatere procese v senescentnih celicah, najpogosteje s senescenco povezan sekretorni fenotip (SASP), ter senolitike, ki senescentne celice odstranijo iz organizma prek izzvane apoptoze. Nekatere od razvitih spojin so že vstopile v klinične faze raziskav. V prvem delu disertacije smo s pomočjo molekulskih simulacij podrobneje preučili enega od mehanizmov, ki vključuje komponente imunskega sistema in je potencialno odgovoren za kopičenje senescentnih celic, povezanih s starostjo. Namreč zaradi povečane prisotnosti inhibitornega kompleksa HLA-E/ß2m/nonapeptid/NKG2A/CD94, ki se tvori med senescentnimi in naravnimi celicami ubijalkami ali celicami CD8+, so te bolj zaščitene pred citotoksičnim delovanjem slednjih. Za celostno obravnavo prepoznave liganda z receptorji imunskih celic smo v raziskavo vključili še komplekse, ki vsebujejo aktivacijski receptor NKG2C/CD49, ki je prav tako prisoten na omenjenih celicah imunskega sistema. Za inhibitorni imunski kompleks smo zgradili model na ravni atomov, opredelili ključne interakcije za prenos signala ter tako postavili izhodišča za racionalno načrtovanje biokemičnih in strukturnih študij kot tudi usmerjeno načrtovanje intervencij za modulacijo zaviralnega učinka na naravne celice ubijalke in celice CD8+. Podobno smo pri modelu na ravni atomov aktivacijskega imunskega kompleksa opredelili ključne interakcije za prenos signala in postavili izhodišča za ciljno načrtovanje nadaljnjih eksperimentov. S pomočjo simulacij smo preučevali še vpliv mutacij nonapeptida na njegovo vezavo na HLA-E in na prenos signala prek inhibitornega receptorja. Tako smo podali smernice za načrtovanje peptidov, peptidomimetikov in malih molekul, ki bi lahko preprečile inhibicijo citotoksičnega učinka imunskih celic. V drugem delu raziskav smo izvedli virtualno rešetanje z uporabo kriterija strukturne podobnosti z izbranimi znanimi senolitiki, da bi identificirali nove spojine s senolitičnimi lastnostmi. Dodatno smo v testiranje vključili tudi nekaj molekul, izbranih glede na podatke iz literature. Senolitični potencial izbranih spojin zadetkov smo testirali na senescentnih fibroblastih, obenem pa v ta namen predhodno razvili in validirali presejalni test za iskanje potencialnih senolitikov. Pridobljena nova spoznanja na področju temeljnega razumevanja regulacije in modulacije količine senescentnih celic prek komponent imunskega sistema ter ovrednotenje nove molekule s senolitičnim učinkom prinašajo nove informacije za ovrednotenje celične senescence kot potencialne nove tarče za zdravljenje s starostjo povezanih bolezni. Aging is the main risk factor for the development of many age-related diseases such as dementia, hypertension, atherosclerosis, cancer, autoimmune and other diseases. Numerous studies show that aging is not a programmed process and that it - along with age-related diseases - can be influenced by external therapeutic approaches. One of these is the modulation or elimination of senescent cells, a type of cells which in response to various stressors stop in the G1 or G2 phase of the cell cycle, express their specific phenotype, and begin to accumulate in the organism as it ages. The field of cellular senescence is a young area of research, so there are many open and unanswered questions regarding the mechanisms of its development as well as the reasons for the accumulation of senescence cells at later ages. Despite these challenges, intensive work is already underway to develop compounds that would show a therapeutic effect through their action on senescence as an increased amount of these cells is directly related to the development of age related diseases. They are divided into two groups: senomorphics, which modulate specific processes in senescent cells, most commonly the senescence-associated secretory phenotype (SASP), and senolytics, which remove senescent cells from the organism by inducing apoptosis. Some of the compounds developed have already entered the clinical phases of research. In the first part of the dissertation, we used molecular simulations to investigate one of the possible mechanisms responsible for the accumulation of senescent cells, which include components of the immune system. Namely, due to the increased presence of the immune inhibitor complex HLA E/β2m/nonapeptide/NKG2A/CD94 formed between the senescent and natural killer cells or CD8+ cells, senescent cells evade the cytotoxic action of the latter. For a comprehensive treatment of ligand recognition by immune cell receptors, we have also investigated systems contains the activating receptor NKG2C/CD94, which is also present on the mentioned cells of the immune system. For the inhibitory immune complex, we created an atomistic model and identified key interactions for signal transduction. This has provided us with a starting point for the rational design of biochemical and structural studies, as well as for the targeted design of interventions to modulate the inhibitory effect on natural killer cells and CD8+ cells. Similarly, we identified key interactions for signal transduction at the atomic level in the activating immune complex model, providing a starting point for the targeted design of further experiments. Using simulations, we also investigated the effect of mutations of nonapeptides on their binding to HLA E and the transduction of an inhibitory signal, providing guidelines for the design of peptides, peptidomimetics, and small molecules that could prevent the inhibition of the cytotoxic effect of immune cells with the inhibitory receptor NKG2A/CD94. In the second part of dissertation, we performed a virtual screening using the criterion of structural similarity with selected known senolytics to identify new compounds with senolytic properties. In addition, we also included in the evaluation some molecules selected based on the available data from the literature. The senolytic potential of the selected hit compounds was tested on senescent fibroblasts. For this purpose, a screening assay for finding potential senolytics was developed and validated. The new acquired knowledge contributed to the fundamental understanding of the regulation and modulation of the number of senescent cells by the components of the immune system, while the discovery of a new molecule with senolytic property provided a new chemical tool useful for the evaluation of cellular senescence as a potential new target for the treatment of age-related diseases.

Disrupted biological function, manifesting through the hallmarks of aging, poses one of the largest threats to healthspan and risk of disease development, such as metabolic disorders, cardiovascular ailments, and neurodegeneration. In recent years, numerous geroprotectors, senolytics, and other nutraceuticals have emerged as potential disruptors of aging and may be viable interventions in the immediate state of human longevity science. In this review, we focus on the decrease in nicotinamide adenine dinucleotide (NAD+) with age and the supplementation of NAD+ precursors, such as nicotinamide mononucleotide (NMN) or nicotinamide riboside (NR), in combination with other geroprotective compounds, to restore NAD+ levels present in youth. Furthermore, these geroprotectors may enhance the efficacy of NMN supplementation while concurrently providing their own numerous health benefits. By analyzing the prevention of NAD+ degradation through the inhibition of CD38 or supporting protective downstream agents of SIRT1, we provide a potential framework of the CD38/NAD+/SIRT1 axis through which geroprotectors may enhance the efficacy of NAD+ precursor supplementation and reduce the risk of age-related diseases, thereby potentiating healthspan in humans., Nutrients, 15 (2), ISSN:2072-6643

Le cancer de l’ovaire est le 2e cancer gynécologique le plus fréquent et le cancer gynécologique le plus mortel en Amérique du Nord. Le carcinome séreux de haut grade (HGSOC) est le sous-type histologique le plus fréquent et est malheureusement associé à un pronostic sombre. Actuellement, le traitement de première ligne consiste en une combinaison de chimiothérapie à base de platine et de taxane ainsi que de chirurgie cytoréductive. Au niveau cellulaire, la chimiothérapie agit en causant des dommages à l’ADN. S’ensuit alors une activation de la réponse aux dommages à l’ADN (DDR), avec une mise en branle des mécanismes de réparation de l’ADN et une activation des checkpoints du cycle cellulaire. Parmi les acteurs de la cascade de la DDR, 53BP1 en particulier joue un rôle important, étant impliqué dans l’amplification du signal de dommages à l’ADN en recrutant d’autres facteurs de la DDR, dans la médiation du choix de la voie de réparation de l’ADN et dans le renforcement des checkpoints du cycle cellulaire. La DDR culmine éventuellement en la prise de décisions de destin cellulaire, c’est-à-dire soit le retour dans le cycle cellulaire après une réparation des dommages, l’induction de la sénescence ou, sinon, une mort cellulaire. La sénescence cellulaire induite par la thérapie (TIS) est d’un intérêt particulier en raison des multiples phénotypes qui lui sont associés, dont le phénotype sécrétoire (SASP), qui agissent sur les cellules cancéreuses et leur microenvironnement avec des effets pro- et anti-tumorigènes, selon le contexte. En médiant les issues thérapeutiques au niveau cellulaire, la DDR, ses composantes et les destins cellulaires qui en découlent médient nécessairement les issues au niveau clinique également. Le premier objectif de cette thèse est donc de caractériser et de déterminer l’importance du TIS dans la réponse à la thérapie dans le HGSOC. À cette fin, nous avons d’abord étudié des cultures primaires de cellules HGSOC. En réponse aux stress génotoxiques, dont la chimiothérapie de première ligne, les cellules développent une TIS caractérisée par un arrêt de prolifération cellulaire, des dommages à l’ADN persistants, un SASP et une sensibilité aux agents sénolytiques. Afin de déterminer la pertinence de la TIS in vivo et en clinique, nous avons ensuite étudié des tissus HGSOC pré- et post-chimiothérapie. Les tissus post-chimiothérapie démontrent des changements au niveau des marqueurs de la sénescence compatibles avec une TIS. De façon intéressante, un signal compatible avec la TIS au niveau de plusieurs marqueurs corrèle avec une meilleure survie à 5 ans, suggérant un effet bénéfique de la TIS au niveau clinique. Le second objectif est de déterminer l’importance de 53BP1 dans les réponses thérapeutiques dans le HGSOC. Pour ce faire, nous avons d’abord étudié la relation entre les niveaux tissulaires de 53BP1 et les issues cliniques dans la cohorte de validation du Canadian Ovarian Experimental Unified Resource (COEUR) et la cohorte du CHUM. Nous avons trouvé que des niveaux élevés de 53BP1 étaient associés, indépendamment de facteurs pronostics établis, à une survie spécifique à la maladie inférieure dans les deux cohortes. Ces résultats ont par la suite été validés sur des données d’expression d’ARNm TP53BP1 dans la cohorte Firehose Legacy du The Cancer Genome Atlas (TCGA). Au niveau cellulaire, nous avons ensuite observé une corrélation positive entre les niveaux endogènes de 53BP1 et la résistance à la carboplatine, ainsi qu’une sensibilisation des cellules à la chimiothérapie avec un knockdown de 53BP1 dans des lignées cellulaires de HGSOC. Ces travaux ont contribué à mieux comprendre les réponses thérapeutiques dans le HGSOC et à identifier de nouvelles potentielles cibles thérapeutiques et pistes de recherche pour l’amélioration du traitement de cette maladie., Ovarian cancer is the second most common and most lethal gynecological malignancy in North America. High-grade serous carcinoma (HGSOC) is the most common histological subtype and is unfortunately associated with a poor prognosis. Current first line treatment consists of a combination of platinum and taxane-based chemotherapy and a cytoreductive surgery. At a cellular level, this chemotherapy acts by causing DNA damage. This leads to the activation of the DNA damage response (DDR), which entails the activation of DNA repair mechanisms and of cell cycle checkpoints. Among the actors in the DDR, 53BP1 in particular plays an important role, being involved in the amplification of the DDR signal through recruitment of DDR factors to the site of DNA damage, in DNA repair pathway choice, and in the reinforcement of cell cycle checkpoints in response to DNA damage. The DDR eventually culminates in the taking of cell fate decisions. Cells may either re-enter the cell cycle after having repaired the damage, or, instead, may undergo senescence or cell death. Treatment-induced senescence (TIS) is of particular interest in cancer, due to the multitude of phenotypes associated with it, most notably the senescence-associated secretory phenotype (SASP), which can have either pro- or anti-cancerous effects on the cancer cells and their surrounding microenvironment. By mediating therapeutic outcomes at a cellular level, the DDR, its actors, and the resulting cell fate decisions necessarily influence outcomes at a clinical level as well. Thus, the first objective of this thesis was to characterise and determine the importance of TIS in HGSOC treatment response. To this end, we first studied primary cultures of HGSOC cells. In response to genotoxic stress, including first line chemotherapy, we found HGSOC primary cultures to develop a TIS characterized by a proliferation arrest, persistent DNA damage, a SASP, and a sensitivity to senolytics. To determine the clinical relevance of these findings, we next studied pre- and post-chemotherapy HGSOC tissues. Post-chemotherapy tissues displayed changes in senescence-associated markers compatible with TIS. Interestingly, a stronger TIS signal with several markers was associated with better 5-year survival, suggesting TIS to be clinically beneficial. The second objective of this thesis was to determine the importance of 53BP1 in HGSOC responses to chemotherapy. We first studied how tissue levels of 53BP1 relate to clinical outcomes in the validation cohort of the Canadian Ovarian Experimental Unified Resource (COEUR) and in an in-house CHUM cohort. We found that high levels of 53BP1 were associated, independently of established prognostic factors, with a poor disease-specific survival in both cohorts. These results were validated in a third cohort, the Firehose Legacy The Cancer Genome Atlas (TCGA) cohort, using TP53BP1 mRNA data. At a cellular level, we next found a positive correlation between 53BP1 levels and resistance to carboplatin in HGSOC cell lines. Furthermore, knockdown of 53BP1 in HGSOC cell lines led to increased sensitivity to chemotherapy. This work contributed to bettering the understanding of responses to therapy in HGSOC and allowed to identify new potential therapeutic targets and avenues for research in order to improve HGSOC therapies.

Retinal degeneration is a debilitating ocular complication characterized by the progressive loss of photoreceptors and other retinal neurons, which are caused by a group of retinal diseases affecting various age groups, and increasingly prevalent in the elderly. Age-related macular degeneration, diabetic retinopathy and glaucoma are among the most common complex degenerative retinal disorders, posing significant public health problems worldwide largely due to the aging society and the lack of effective therapeutics. Whilst pathoetiologies vary, if left untreated, loss of retinal neurons can result in an acquired degeneration and ultimately severe visual impairment. Irrespective of underlined etiology, loss of neurons and supporting cells including retinal pigment epithelium, microvascular endothelium, and glia, converges as the common endpoint of retinal degeneration and therefore discovery or repurposing of therapies to protect retinal neurons directly or indirectly are under intensive investigation. This review overviews recent developments of potential neuroprotectants including neuropeptides, exosomes, mitochondrial-derived peptides, complement inhibitors, senolytics, autophagy enhancers and antioxidants either still experimentally or in clinical trials. Effective treatments that possess direct or indirect neuroprotective properties would significantly lift the burden of visual handicap.

Senolytics are basically anti-cancer drugs, repurposed to kill senescent cells selectively. It is even more difficult to selectively kill senescent cells than to kill cancer cells. Based on lessons of cancer therapy, here I suggest how to exploit oncogene-addiction and to combine drugs to achieve selectivity. However, even if selective senolytic combinations will be developed, there is little evidence that a few senescent cells are responsible for organismal aging. I also discuss gerostatics, such as rapamycin and other rapalogs, pan-mTOR inhibitors, dual PI3K/mTOR inhibitors, which inhibit growth- and aging-promoting pathways. Unlike senolytics, gerostatics do not kill cells but slow down cellular geroconversion to senescence. Numerous studies demonstrated that inhibition of the mTOR pathways by any means (genetic, pharmacological and dietary) extends lifespan. Currently, only two studies demonstrated that senolytics (fisetin and a combination Dasatinib plus Quercetin) extend lifespan in mice. These senolytics slightly inhibit the mTOR pathway. Thus, life extension by these senolytics can be explained by their slight rapamycin-like (gerostatic) effects.

Cellular senescence (CS) is increasingly implicated in the etiology of age-related diseases. While CS can facilitate physiological processes such as tissue repair and wound healing, senescent cells also contribute to pathophysiological processes involving macromolecular damage and metabolic dysregulation that characterize multiple morbid and prevalent diseases, including Alzheimer's disease, osteoarthritis, atherosclerotic vascular disease, diabetes mellitus, and idiopathic pulmonary fibrosis (IPF). Preclinical studies targeting senescent cells and the senescence-associated secretory phenotype (SASP) with "senotherapeutics" have demonstrated improvement in age-related morbidity associated with these disease states. Despite promising results from these preclinical trials, few human clinical trials have been conducted. A first-in-human, open-label, pilot study of the senolytic combination of dasatinib and quercetin (DQ) in patients with IPF showed improved physical function and mobility. In this review, we will discuss our current understanding of cellular senescence, its role in age-associated diseases, with a specific focus on IPF, and potential for senotherapeutics in the treatment of fibrotic lung diseases.

Senolytics are a group of medicinal substances that selectively remove the so-called aging cells. The available theories indicate that these cells are resistant to apoptosis and accumulate at the causal sites of many chronic disorders and diseases, are metabolically active, and may acquire a proinflammatory, pro-apoptotic secretory phenotype that destroys healthy tissues. This results in the release of tissue-damaging pro-inflammatory cytokines, chemokines, and proteases. The most disturbing phenomenon is the innate immunity of aging cells to these factors. Aging cells undergo also metabolic changes, i.e. decreased use of fatty acids, increased glycolysis, and increased production of reactive oxygen species, which can affect other cells and even spread the aging process. Senolytic drugs (including Dasatinib, Quercetin, Fisetin, Navitoclax) have the ability to temporarily turn off the ability to defend against apoptosis. The senescent cells take weeks to accumulate again, so these substances can be given intermittently, reducing the likelihood of side effects. In preclinical models, it was shown that senolytics delay the processes of e.g. weakness, cancer, and dysfunction of the cardiovascular system, liver, kidneys, musculoskeletal system, lungs, eyes. However, ongoing clinical trials for diabetes, idiopathic pulmonary fibrosis, Alzheimer's disease, COVID-19, osteoarthritis, osteoporosis, and bone marrow transplantation have not yet been completed. Pending the results confirming the safety, tolerability, and efficacy of these substances, they cannot be used by patients until then. Despite this, many senolytic substances are now available in the form of dietary supplements. The pharmaceutical market and the production of dietary supplements are developing very dynamically, new technologies and new applications are constantly being discovered. However, supplements are not subject to any control as to the quality of the finished preparations and their composition, which may increase the danger of their use. By assumption, supplements contain ingredients that are supposed to support the functioning of our body, not to heal. Therefore, it is worth considering the need for supplementation, especially since supplements can be overdosed and may also react with drugs, which may have unforeseen effects. © 2021 Polish Pharmaceutical Society. All rights reserved.

Cellular senescence is a process that can prevent tumour development in a cell autonomous manner by imposing a stable cell cycle arrest after oncogene activation. Paradoxically, senescence can also promote tumour growth cell non-autonomously by creating a permissive tumour microenvironment that fuels tumour initiation, progression to malignancy and metastasis. In a pituitary tumour known as adamantinomatous craniopharyngioma (ACP), cells that carry oncogenic β-catenin mutations and overactivate the WNT signalling pathway form cell clusters that become senescent and activate a senescence-associated secretory phenotype (SASP). Research in mouse models of ACP has provided insights into the function of the senescent cell clusters and revealed a critical role for SASP-mediated activities in paracrine tumour initiation. In this review, we first discuss this research on ACP and subsequently explore the theme of paracrine tumourigenesis in other tumour models available in the literature. Evidence is accumulating supporting the notion that paracrine signalling brought about by senescent cells may underlie tumourigenesis across different tumours and cancer models.

The objective of the review is to identify and summarize clinical and basic research addressing or underpinning the use of pharmaceuticals or biopharmaceuticals for engineered negligible senescence.

Cellular senescence is a hallmark of aging and a promising target for therapeutic approaches. The identification of senescent cells requires multiple biomarkers and complex experimental procedures, resulting in increased variability and reduced sensitivity. Here, we propose a simple and broadly applicable imaging flow cytometry (IFC) method. This method is based on measuring autofluorescence and morphological parameters and on applying recent artificial intelligence (AI) and machine learning (ML) tools. We show that the results of this method are superior to those obtained measuring the classical senescence marker, senescence-associated beta-galactosidase (SA-β-Gal). We provide evidence that this method has the potential for diagnostic or prognostic applications as it was able to detect senescence in cardiac pericytes isolated from the hearts of patients affected by end-stage heart failure. We additionally demonstrate that it can be used to quantify senescence “in vivo” and can be used to evaluate the effects of senolytic compounds. We conclude that this method can be used as a simple and fast senescence assay independently of the origin of the cells and the procedure to induce senescence.

Cardiovascular diseases (CVD) are predominantly an aging disease. Important sex-specific differences exist and the mechanism(s) by which this sex-by-age interaction influences CVD development and progression remains elusive. Accordingly, it is still unknown whether cell senescence, a main feature of cardiac male aging, is a significant feature also of the female aged mouse heart and whether senolytics, senescence-clearing compounds, promote myocardial repair and regeneration after myocardial infarction (MI) in aged female mice. To this aim, the combination of two senolytics, dasatinib and quercetin (D+Q) or just their vehicle was administered to 22-24 months old C57BL/6 female mice after MI. D+Q improved global left ventricle function and myocardial performance after MI whereby female cardiac aging is characterized by accumulation of cardiac senescent cells that are further increased by MI. Despite their terminal differentiation nature, also cardiomyocytes acquire a senescent phenotype with age in females. D+Q removed senescent cardiac non-myocyte and myocyte cells ameliorating cardiac remodeling and regeneration. Senolytics removed aged dysfunctional cardiac stem/progenitor cells (CSCs), relieving healthy CSCs with normal proliferative and cardiomyogenic differentiation potential. In conclusions, cardiac senescent cells accumulate in the aged female hearts. Removing senescent cells is a key therapeutic target for efficient repair of the aged female heart.

Aging, a time-dependent loss of physiological function, and its drivers are turning into a significant topic of research as the population's mean age increases. Epigenetic alterations, telomere shortening or dysfunction, mitogenic stress, oxidative stress, or accumulation of DNA damage can drive the cell to senescence: a permanent cell cycle arrest sometimes associated with a secretory phenotype and inflammatory consequences in the surrounding tissue. The amount of senescent cells grows over time in older organisms and may induce tissue inflammation and threaten overall tissue homeostasis, favoring aging. Senolytic and senomorphic therapeutics are an emerging approach to eliminate senescent cells or to block their secretory phenotypes respectively. Given that people living with HIV suffer non-AIDS comorbidities in a higher prevalence than the general population, aging is accentuated among them. Inflammation biomarkers may be helpful to assess prognosis or act as surrogate endpoints for studies of strategies focused on reversal of HIV-associated accelerated aging. This review summarizes the latest findings in aging and its major drivers, under the light of HIV infection. Since the number of older PLWH is currently rising, it will be of great importance to address and treat their age-related conditions, as well as to better decipher their biological mechanisms.

Cellular senescence, one of the hallmarks of aging, refers to permanent cell cycle arrest and is accelerated during the aging process. Black ginseng (BG), prepared by a repeated steaming and drying process nine times from fresh ginseng (Panax ginseng C.A. Meyer), is garnering attention for herbal medicine due to its physiological benefits against reactive oxygen species (ROS), inflammation, and oncogenesis, which are common cues to induce aging. However, which key nodules in the cellular senescence process are regulated by BG supplementation has not been elucidated yet. In this study, we investigated the effects of BG on cellular senescence using in vitro and aged mouse models. BG-treated primary mouse embryonic fibroblasts (MEFs) in which senescence was triggered by ionizing radiation (IR) expressed less senescence-associated β-galactosidase (SA-β-gal)-positive stained cells. In our aged mice (18 months old) study, BG supplementation (300 mg/kg) for 4 weeks altered hepatic genes involved in the aging process. Furthermore, we found BG supplementation downregulated age-related inflammatory genes, especially in the complement system. Based on this observation, we demonstrated that BG supplementation led to less activation of the canonical senescence pathway, p53-dependent p21 and p16, in multiple metabolic organs such as liver, skeletal muscle and white adipose tissue. Thus, we suggest that BG is a potential senolytic candidate that retards cellular senescence.

Purpose of review Drug use in elderly people is high compared to younger people. Simultaneously, elderly are at greater risk when exposed to environmental substances. It is puzzling therefore, that ageing, as a variable in pharmacological and toxicological processes is not investigated in more depth. Moreover, recent data suggest that molecular manifestations of the ageing process also hallmark the pathogenesis of chronic lung diseases, which may impact pharmacology and toxicology. Recent findings In particular, absorption, distribution, metabolism and excretion (ADME) processes of drugs and toxins alter because of ageing. Polypharmacy, which is quite usual with increasing age, increases the risk of drug-drug interactions. Individual differences in combination of drugs use in conjunction with individual variations in drug metabolizing enzymes can influence lung function. Exploring exposure throughout life (i.e. during ageing) to potential triggers, including polypharmacy, may avoid lung disease or unexplained cases of lung damage. Understanding of the ageing process further unravels critical features of chronic lung disease and helps to define new protective targets and therapies. Optimizing resilience can be key in pharmacology and toxicology and helps in maintaining healthy lungs for a longer period.

In recent years, cellular senescence has become the focus of attention in multiple areas of biomedical research. Typically defined as an irreversible cell cycle arrest accompanied by increased cellular growth, metabolic activity and by a characteristic messaging secretome, cellular senescence can impact on multiple physiological and pathological processes such as wound healing, fibrosis, cancer and ageing. These unjustly called ‘zombie cells’ are indeed a rich source of opportunities for innovative therapeutic development. In this review, we collate the current understanding of the process of cellular senescence and its two-faced nature, i.e. beneficial/detrimental, and reason this duality is linked to contextual aspects. We propose the senescence programme as an endogenous pro-resolving mechanism that may lead to sustained inflammation and damage when dysregulated or when senescent cells are not cleared efficiently. This pro-resolving model reconciles the paradoxical two faces of senescence by emphasising that it is the unsuccessful completion of the programme, and not senescence itself, what leads to pathology. Thus, pro-senescence therapies under the right context, may favour inflammation resolution. We also review the evidence for the multiple therapeutic approaches under development based on senescence, including its induction, prevention, clearance and the use of senolytic and senomorphic drugs. In particular, we highlight the importance of the immune system in the favourable outcome of senescence and the implications of an inefficient immune surveillance in completion of the senescent cycle. Finally, we identify and discuss a number of challenges and existing gaps to encourage and stimulate further research in this exciting and unravelled field, with the hope of promoting and accelerating the clinical success of senescence-based therapies.

Aging is a major risk factor for numerous human pathologies, including cardiovascular, metabolic, musculoskeletal, and neurodegenerative conditions and various malignancies. While our understanding of aging is far from complete, recent advances suggest that targeting fundamental aging processes can delay, prevent, or alleviate age-related disorders. Cellular senescence is physiologically beneficial in several contexts, but it has causal roles in multiple chronic diseases. New studies have illustrated the promising feasibility and safety to selectively ablate senescent cells from tissues, a therapeutic modality that holds potential for treating multiple chronic pathologies and extending human healthspan. Here, we review molecular links between cellular senescence and age-associated complications and highlight novel therapeutic avenues that may be exploited to target senescent cells in future geriatric medicine.

COVID-19 is not deadly early in life, but mortality increases exponentially with age, which is the strongest predictor of mortality. Mortality is higher in men than in women, because men age faster, and it is especially high in patients with age-related diseases, such as diabetes and hypertension, because these diseases are manifestations of aging and a measure of biological age. At its deepest level, aging (a program-like continuation of developmental growth) is driven by inappropriately high cellular functioning. The hyperfunction theory of quasi-programmed aging explains why COVID-19 vulnerability (lethality) is an age-dependent syndrome, linking it to other age-related diseases. It also explains inflammaging and immunosenescence, hyperinflammation, hyperthrombosis, and cytokine storms, all of which are associated with COVID-19 vulnerability. Anti-aging interventions, such as rapamycin, may slow aging and age-related diseases, potentially decreasing COVID-19 vulnerability.

Life expectancy has increased substantially over the last few decades, leading to a worldwide increase in the prevalence and burden of aging-associated diseases. Recent evidence has proven that cellular senescence contributes substantially to the development of these disorders. Cellular senescence is a state of cell cycle arrest with suppressed apoptosis and concomitant secretion of multiple bioactive factors (the senescence-associated secretory phenotype—SASP) that plays a physiological role in embryonic development and healing processes. However, DNA damage and oxidative stress that occur during aging cause the accumulation of senescent cells, which through their SASP bring about deleterious effects on multiple organ and systemic functions. Ablation of senescent cells through genetic or pharmacological means leads to improved life span and health span in animal models, and preliminary evidence suggests it may also have a positive impact on human health. Thus, strategies to reduce or eliminate the burden of senescent cells or their products have the potential to impact multiple clinical outcomes with a single intervention. In this review, we touch upon the basics of cell senescence and summarize the current state of development of therapies against cell senescence for human use.

Senescent cells accumulate with aging and at etiological sites of multiple diseases, including those accounting for most morbidity, mortality, and health costs. Senescent cells do not replicate, can release factors that cause tissue dysfunction, and yet remain viable. The discovery of senolytic drugs, agents that selectively eliminate senescent cells, created a new route for alleviating age‐related dysfunction and diseases. As anticipated for agents targeting fundamental aging mechanisms that are ‘root cause’ contributors to multiple disorders, potential applications of senolytics are protean. We review the discovery of senolytics, strategies for translation into clinical application, and promising early signals from clinical trials., Senescent cells accumulate with aging and at etiological sites of multiple diseases, including those accounting for most morbidity, mortality, and health costs. Senescent cells do not replicate, can release factors that cause tissue dysfunction, and yet remain viable. The discovery of senolytics offers a new route for alleviating age‐related dysfunction and diseases. We review the discovery of senolytics, strategies for translation into clinical application, and promising early signals from clinical trials.

Uncontrolled proliferative diseases, such as fibrosis or cancer, can be fatal. We previously found that a compound containing the chromone scaffold (CS), ONG41008, had potent antifibrogenic effects associated with EMT or cell-cycle control resembling tumorigenesis. We investigated the effects of ONG41008 on tumor cells and compared these effects with those in pathogenic myofibroblasts. Stimulation of A549 (lung carcinoma epithelial cells) or PANC1 (pancreatic ductal carcinoma cells) with ONG41008 resulted in robust cellular senescence, indicating that dysregulated cell proliferation is common to fibrotic cells and tumor cells. The senescence was followed by multinucleation, a manifestation of mitotic slippage. There was significant upregulation of expression and rapid nuclear translocation of p-TP53 and p16 in the treated cancer cells, which thereafter died after 72 h confirmed by 6 day live imaging. ONG41008 exhibited a comparable senogenic potential to that of dasatinib. Interestingly, ONG41008 was only able to activate caspase-3, 7 in comparison with quercetin and fisetin, also containing CS in PANC1. ONG41008 did not seem to be essentially toxic to normal human lung fibroblasts or primary prostate epithelial cells, suggesting ONG41008 can distinguish the intracellular microenvironment between normal cells and aged or diseased cells. This effect might occur as a result of the increased NAD/NADH ratio, because ONG41008 restored this important metabolic ratio in cancer cells. Taken together, this is the first study to demonstrate that a small molecule can arrest uncontrolled proliferation during fibrogenesis or tumorigenesis via both senogenic and senolytic potential. ONG41008 could be a potential drug for a broad range of fibrotic or tumorigenic diseases.

Background: Induced senescence could be exploited to selectively counteract the proliferation of cancer cells and target them for senolysis. We examined the cellular senescence induced by curcumin and whether it could be targeted by fisetin and quercetin, flavonoids with senolytic activity. Methods: Cell-cycle profiles, chromosome number and structure, and heterochromatin markers were evaluated via flow cytometry, metaphase spreads, and immunofluorescence, respectively. The activation of p21waf1/cip1 was assessed via RT-qPCR and immunoblotting. Senescent cells were detected via SA-β-Galactosidase staining. Results: We report that curcumin treatment specifically triggers senescence in cancer cells by inducing mitotic slippage and DNA damage. We show that curcumin-induced senescence is p21waf1/cip1-dependent and characterized by heterochromatin loss. Finally, we found that flavonoids clear curcumin-induced senescent cancer cells. Conclusions: Our findings expand the characterization of curcumin-induced cellular senescence in cancer cells and lay the foundation for the combination of curcumin and flavonoids as a possible anti-cancer therapy.

Radiotherapy (RT) is a key component of cancer treatment. Although improvements have been made over the years, radioresistance remains a challenge. For this reason, a better understanding of cell fates in response to RT could improve therapeutic options to enhance cell death and reduce adverse effects. Here, we showed that combining RT (photons and protons) to noncytotoxic concentration of PARP inhibitor, Olaparib, induced a cell line-dependent senescence-like phenotype. The senescent cells were characterized by morphological changes, an increase in p21 mRNA expression as well as an increase in senescence-associated β-galactosidase activity. We demonstrated that these senescent cells could be specifically targeted by Navitoclax (ABT-263), a Bcl-2 family inhibitor. This senolytic drug led to significant cell death when combined with RT and Olaparib, while limited cytotoxicity was observed when used alone. These results demonstrate that a combination of RT with PARP inhibition and senolytics could be a promising therapeutic approach for cancer patients.

Cellular senescence plays a key role in mediating tissue remodeling and modulation of host responses to pathogenic stimuli. Our current study was designed to gain a better understanding of the impact of short-term senolytic treatment or inflammatory stimulation on lung senescence. The results of our study demonstrate that short term treatment of aged adult mice (20 months of age) with senolytics, quercetin, and dasatinib decreases p16 and p21 expression in lung tissue. Short-term treatment with senolytics also significantly improved the expression of genes associated with genomic instability, telomere attrition, mitochondrial dysfunction, DNA binding, and the inflammatory response. In contrast, in response to low-dose LPS administration, there was increased expression of genes associated with genomic instability, mitochondrial dysfunction, and heightened inflammatory responses in young adult murine lung (3 months of age). Taken together, the results of our current study illustrate the efficacy of senolytic treatment on modulating responses in aged lung and the potential role of chronic low dose inflammation on senescence induction in the lung.

The incidence of age associated chronic diseases has increased in recent years. Although several diverse causes produce these phenomena, abundant evidence shows that oxidative stress plays a central role. In recent years, numerous studies have focused on elucidating the role of oxidative stress in the development and progression of both aging and chronic diseases, opening the door to the discovery of new underlying mechanisms and signaling pathways. Among them, senolytics and senomorphics, and extracellular vesicles offer new therapeutic strategies to slow the development of aging and its associated chronic diseases by decreasing oxidative stress. In this review, we aim to discuss the role of extracellular vesicles in human cardiorenal syndrome development and their possible role as biomarkers, targets, or vehicles of drugs to treat this syndrome.

Cancer is one of the main causes of death worldwide, and, among the most frequent cancer types, osteosarcoma accounts for 56% of bone neoplasms observed in children and colorectal cancer for 10.2% of tumors diagnosed in the adult population. A common and frequent hurdle in cancer treatment is the emergence of resistance to chemo- and radiotherapy whose biological causes are largely unknown. In the present work, human osteosarcoma (SAOS) and colorectal adenocarcinoma (HT29) cell lines were γ-irradiated at doses mimicking the sub-lethal irradiation in clinical settings to obtain two radio-resistant cellular sub-populations named SAOS400 and HT500, respectively. Since “therapy-induced senescence” (TIS) is often associated with tumor response to radiotherapy in cancer cells, we measured specific cellular and biochemical markers of senescence in SAOS400 and HT500 cells. In detail, both cell lines were characterized by a higher level of expression of cyclin-dependent kinase inhibitors p16INK4 and p21CIP1 and increased positivity to SAβ-gal (senescence-associated β-galactosidase) with respect to parental cells. Moreover, the intracellular levels of reactive oxygen species in the resistant cells were significantly lower compared to the parental counterparts. Subsequently, we demonstrated that senolytic agents were able to sensitize SAOS400 and HT500 to cell death induced by γ-irradiation. Employing two natural flavonoids, fisetin and quercetin, and a BH3-mimetic, ABT-263/navitoclax, we observed that their association with γ-irradiation significantly reduced the expression of p16INK4, p21CIP1 and synergistically (combination index < 1) increased cell death compared to radiation mono-alone treatments. The present results reinforce the potential role of senolytics as adjuvant agents in cancer therapy.

In response to oncogene expression (such as BRAF-V600E), genotoxic insults, or other stresses, eukaryotic cells can suppress apoptosis and enter senescence. Senescence is a cell fate characterized by a quasi-irreversible proliferative arrest and deep transcriptional reprogramming, notably leading to an important secretion of inflammatory factors collectively termed the senescence-associated secretory phenotype (SASP). Due to increased secretory demands and chronic stress, proteostasis may be challenged in senescence. As it limits the proliferation of cells possibly bearing pre-neoplastic potential, senescence is an essential tumor suppressing process; however, the accumulation of senescent cells during aging, in pathological contexts, or following chemotherapy or radiotherapy, is detrimental and leads to tissue dysfunction. Senolytics are drugs that selectively induce apoptosis in senescent cells while sparing normal cells, and their therapeutical application has proved a valuable pharmacological strategy in pathological contexts in which senescence plays a driving role. The aim of this project was to identify novel senolytic compounds, notably in BRAF-V600E-induced senescence, and to characterize their mechanisms of action, thereby adding to the understanding of cell survival pathways regulation in senescence. Cardioglycosides constitute a class of drugs that were identified as potent senolytics in the screen of a repurposing library. We showed that BRAF-V600E senescent cells were remarkably sensitive to senolysis induced by cardioglycosides. We demonstrated that BRAF-V600E senescent cells have a heightened autophagy flux that is essential to their survival, and that cardioglycosides acted as senolytics by inhibiting autophagy through Na,K-ATPase signal transduction. Accordingly, blocking autophagy through other routes such as with chloroquine was also senolytic. To gain insight into the regulation of autophagy and proteostasis in senescence and identify new senolytic targets, we then assessed endoplasmic reticulum stress and the unfolded protein response (UPR) in different senescence models. In parallel, we screened various chemical libraries, in which we identified potential senolytics targeting different facets of proteostasis. Interestingly, we found that UPR sensor Ire1 was upregulated in oncogene-induced senescence. Ire1 regulates cell fate through several pathways, and many small compounds that differentially modulate its activity are available. We thus employed a panel of Ire1 modulators to begin characterizing its role in senescence, and establish novel senolytic strategies. Collectively, our results highlight the senolytic potential of targeting autophagy and proteostasis in oncogene-induced senescence, and the importance of deciphering the mechanisms of action of senolytics to identify new targets and regulatory pathways., En réponse à l'expression d'oncogène (tel que BRAF-V600E), à des traitements génotoxiques ou à d'autres stress, les cellules eucaryotes peuvent éviter l'apoptose et déclencher la sénescence. La sénescence est un destin cellulaire caractérisé par un arrêt prolifératif quasi-irréversible et une reprogrammation transcriptionnelle profonde, conduisant notamment à une sécrétion importante de facteurs inflammatoires collectivement appelés phénotype sécrétoire associé à la sénescence (SASP). En raison de l'augmentation de la demande sécrétoire et de stress chroniques, la protéostase peut être perturbée en sénescence. Comme elle limite la prolifération de cellules susceptibles de présenter un potentiel pré-néoplastique, la sénescence est un processus essentiel de suppression tumorale ; cependant, l'accumulation de cellules sénescentes au cours du vieillissement, dans des contextes pathologiques, ou après chimiothérapie ou radiothérapie, est préjudiciable et entraîne un dysfonctionnement tissulaire. Les sénolytiques sont des composés qui induisent sélectivement l'apoptose dans les cellules sénescentes tout en épargnant les cellules normales, et leur application thérapeutique s'est avérée une stratégie pharmacologique efficace dans différents contextes pathologiques où la sénescence joue un rôle moteur. Le but de ce projet était d'identifier de nouveaux composés sénolytiques, notamment dans la sénescence induite par BRAF-V600E, et de caractériser leurs mécanismes d'action, ajoutant ainsi à la compréhension de la régulation des voies de survie cellulaire en sénescence. Les cardioglycosides constituent une classe de composés qui ont été identifiés comme de puissants sénolytiques dans le criblage d'une chimiothèque de repositionnement. Nous avons montré que les cellules sénescentes BRAF-V600E étaient remarquablement sensibles à la sénolyse induite par les cardioglycosides. Nous avons démontré que les cellules sénescentes BRAF-V600E ont un flux autophagique accru, essentiel à leur survie, et que les cardioglycosides agissent comme sénolytiques en inhibant l'autophagie via la transduction du signal par la Na,K-ATPase. En conséquence, le blocage de l'autophagie par d'autres voies, comme avec la chloroquine, était également sénolytique. Pour mieux comprendre la régulation de l'autophagie et de la protéostase en sénescence et identifier de nouvelles cibles sénolytiques, nous avons ensuite évalué le stress du réticulum endoplasmique et la réponse aux protéines mal repliées (UPR) dans différents modèles de sénescence. En parallèle, nous avons criblé diverses chimiothèques, dans lesquelles nous avons identifié des sénolytiques potentiels ciblant différentes facettes de la protéostase. Notamment, nous avons découvert que le senseur de l'UPR Ire1 était régulé à la hausse en sénescence induite par l'expression d'oncogènes. Ire1 régule le destin cellulaire par plusieurs voies, et de nombreux composés qui modulent de manière différentielle son activité sont disponibles. Nous avons donc utilisé un panel de modulateurs d'Ire1 pour commencer à caractériser son rôle en sénescence, et établir de nouvelles stratégies sénolytiques. En résumé, nos résultats soulignent le potentiel sénolytique du ciblage de l'autophagie et de la protéostase dans la sénescence induite par l'expression d'oncogènes, et l'importance de caractériser en détails les mécanismes d'action des sénolytiques pour identifier de nouvelles cibles et voies de régulation.

Kod kroničnih plućnih bolesti postoje nakupine senescentnih stanica. Senoterapeutici djeluju na sam uzrok bolesti i time se sprječava progresija plućnih bolesti. Senolitici su lijekovi koji potiču apoptozu senescentnih stanica. Prirodni senolitici su kvercetin, fisetin, piperlongumin, kurkumin i kardiotonični glikozidi. Nedostatak im je slaba bioraspoloživost, a prednost im je niska toksičnost. Sintetizirani su sintetski senolitici, ali dosta njih ima nuspojave. Senolitici onemogućavaju SCAP antiapoptozne putove kojima se senescentna stanica štiti od apoptoze. Time se potiče apoptoza senescentnih stanica. Postoje galaktoza-konjugirani senolitički prolijekovi, inhibitori Hsp90, dasatinib, panobinostat, A1331852, A1155463, navitoklaks (ABT263), sintetski peptid FOXO4-DRI te imunosna terapija CAR T stanicama. S druge strane, postoje senostatici koji sprječavaju stanice da postanu senescentne blokirajući signalne putove koji vode u senescenciju. Kombinacijom senolitika sa senostaticima se može djelovati na različite mehanizme istovremeno. Senostatici blokiraju PI3K-mTOR signalni put. Senostatici su rapamicin, metformin, AICAR, biljni polifenol resveratrol, STAC, antagomiri miR-34a/miR-570 te antioksidansi, uključujući melatonin. Sprječavanjem oksidacijskog stresa se sprječava oštećenje DNA, a time i senescencija. Zbog nuspojava rapamicina razvijeni su manje toksični lijekovi rapalogs. Zbog slabe bioraspoloživosti resveratrola razvijeni su sintetski STAC lijekovi. Većinom su sva ispitivanja provedena na miševima pa je potrebno još puno istraživanja provesti da bi se dokazala učinkovitost i sigurnost ovakvih lijekova na ljudima. Jedino ispitivanje na ljudima je provedeno s kombinacijom dasatinib i kvercetin čime se dokazala učinkovitost uz prihvatljive nuspojave. In chronic lung diseases, there are clusters of senescent cells. Senotherapeutics act on the cause of the disease and thus prevent the progression of lung diseases. Senolytics are drugs that promote apoptosis of senescent cells. Natural senolytics are quercetin, fisetin, piperlongumin, curcumin and cardiotonic glycosides. Their disadvantage is poor bioavailability, and their advantage is low toxicity. Synthetic senolytics have been synthesized, but many have side effects. Senolytics disable SCAP antiapoptotic pathways that protect the senescent cell from apoptosis. This promotes apoptosis of senescent cells. There are galactose-conjugated senolytic prodrugs, Hsp90 inhibitors, dasatinib, panobinostat, A1331852, A1155463, navitoclax (ABT263), the synthetic peptide FOXO4-DRI, and CAR T cell immune therapy. On the other hand, there are senostatics that prevent cells from becoming senescent by blocking signaling pathways leading to senescence. By combining senolytics with senostatics, different mechanisms can be acted upon simultaneously. Senostatics block the PI3K-mTOR signaling pathway. Senostatics include rapamycin, metformin, AICAR, plant polyphenol resveratrol, STAC, miR-34a / miR-570 antagonists, and antioxidants including melatonin. Preventing oxidative stress prevents DNA damage and thus senescence. Due to the side effects of rapamycin, less toxic drugs rapalogs have been developed. Due to the poor bioavailability of resveratrol, synthetic STAC drugs have been developed. Most of the tests have been performed on mice, so much more research is needed to prove the effectiveness and safety of such drugs in humans. The only human study was performed with a combination of dasatinib and quercetin to demonstrate efficacy with acceptable side effects.

Drug-induced senescence program may be activated both in normal and cancer cells as a consequence of chemotherapeutic treatment, leading to some adverse side effects such as senescence-associated secretory phenotype (SASP), secondary senescence, and cancer promotion. Targeted elimination of senescent cells can be achieved by drugs with senolytic activity (senolytics), for example, the plant-derived natural compound quercetin, especially when co-treated with kinase inhibitor dasatinib. In the present study, three quercetin derivatives were synthesized and tested for improved senolytic action against etoposide-induced senescent human normal mammary epithelial cells and triple-negative breast cancer cells in vitro. Transformation of catechol moiety into diphenylmethylene ketal and addition of three acetyl groups to the quercetin molecule (QD3 derivative) promoted the clearance of senescent cancer cells as judged by increased apoptosis compared to etoposide-treated cells. A QD3-mediated senolytic effect was accompanied by decreased SA-beta galactosidase activity and the levels of p27, IL-1β, IL-8, and HSP70 in cancer cells. Similar effects were not observed in senescent normal cells. In conclusion, a novel senolytic agent QD3 was described as acting against etoposide-induced senescent breast cancer cells in vitro. Thus, a new one-two punch anti-cancer strategy based on combined action of a pro-senescence anti-cancer drug and a senolytic agent is proposed.

Peri-implantitis is a disease that causes the detachment of orthodontic mini-implants. Recently, stress-induced senescent cells have been reported to be involved in various inflammatory diseases. Senescent cell-eliminating drugs, termed “senolytics”, can improve the symptoms of such diseases. However, the relationship between peri-implantitis and senescent cells remains unclear. In this study, we evaluated the presence of senescent cells in a rat peri-implantitis model developed with a gum ring. The effect on bone resorption and implant loss was also investigated with and without senolytics (Dasatinib and Quercetin). The number of senescence markers (p19, p21, and p16) was found to increase, and implant detachment occurred in 24 days. After the administration of senolytics, the number of senescence markers decreased and implant detachment was inhibited. This study suggests that senescent cells aggravate peri-implantitis and senolytic administration latently reduces implant loss by inhibiting senescence-related mechanisms.

We previously demonstrated that SAOS human osteosarcoma cells, incubated with carotenoid-enriched nanoemulsions (CEN), activated a nonprotective form of autophagy and delayed cell proliferation. The present work focuses on the biological effects of CEN on a derivative of SAOS cells named SAOS400, recently described for their radiation resistance and higher expression of therapy-induced senescence (TIS) markers. SAOS400 cells, incubated with CEN, activated a “cytostatic” form of autophagy confirmed by cell cycle arrest in the G2/M phase and increased expression of autophagic proteins. Treatment of SAOS400 cells with CEN also resulted in decreased expression of the senescence marker p16INK4. However, when SAOS400 cells were γ-irradiated in combination with CEN, the threshold for cell death was reached (>60% after 96 h). We showed that this type of cell death corresponded to ‘cytotoxic’ or ‘lethal’ autophagy and that the combined treatment of CEN plus γ-rays was synergistic, with the combination index < 1. Since CEN contained β-carotene, the pure compound was used in SAOS400 cells at the same concentration present in CEN and up to 10 times higher. However, no radio-sensitizing effect of β-carotene was observed, suggesting that the biological effect of CEN was due to less abundant but more bioactive molecules, or to the synergistic activity of multiple components present in the extracts, confirming the functional pleiotropy of natural extracts enriched in bioactive molecules.

Despite important advances in the treatment of myocardial infarction that have significantly reduced mortality, there is still an unmet need to limit the infarct size after reperfusion injury in order to prevent the onset and severity of heart failure. In the research arena, multiple cardioprotective maneuvers, therapeutic targets, peptides and drugs have been developed to effectively protect the myocardium from reperfusion-induced cell death in preclinical studies. Nonetheless, the translation of these therapies from laboratory to clinical contexts has proven to be quite challenging. Comorbidities, comedications or inadequate ischemia/reperfusion experimental models are clearly identified variables that need to be accounted for in order to achieve effective cardioprotection studies. The aging heart is characterized by altered proteostasis, DNA instability, epigenetic changes, among others. A vast number of studies has shown that multiple therapeutic strategies, such as ischemic conditioning phenomena and protective drugs are unable to protect the aged heart from myocardial infarction. In this Mini-Review, we will provide an updated state of the art concerning potential new cardioprotective strategies targeting the aging heart.

Relatório de Estágio do Mestrado Integrado em Ciências Farmacêuticas apresentado à Faculdade de Farmácia Realizado no âmbito da Unidade Curricular “Estágio Curricular” do Mestrado Integrado em Ciências Farmacêuticas da Faculdade de Farmácia da Universidade de Coimbra, o presente trabalho contem: o Relatório de Estágio em Indústria Farmacêutica, realizado junto da equipa responsável pelo Cosmedesk, no período de 3 de maio de 2021 a 30 de julho de 2021; o Relatório de Estágio em Farmácia Comunitária, realizado na Farmácia S. José, Coimbra, no período de 3 de janeiro a 30 de abril de 2021; e a monografia intitulada “Senolytics and Senomorphics for the Treatment of Osteoarthritis”.A Osteoartrite (OA) é uma doença degenerativa das articulações que resulta em perda de qualidade de vida e incapacidade. A senescência celular, um dos fenómenos associados ao envelhecimento, tem sido associada ao desenvolvimento e progressão da OA. Novas terapias focadas na senescência celular tem sido alvo de pesquisa. Senolíticos são fármacos que levam à eliminação das células senescentes. Senomórficos são fármacos que interferem nas vias e fatores do fenótipo associado à senescência. Resultados demonstraram que os senolíticos e senomórficos são capazes de abrandar a patogénese da OA e reduzir a sintomatologia associada. No entanto, mais investigação é necessária para avaliar eficiência, segurança e efeitos adversos destes compostos. Perante os resultados positivos e a ausência de terapias que abrandem o desenvolvimento da doença, senolíticos e senomórficos surgem como uma abordagem terapêutica muito promissora para a OA. Carried out within the scope of the Curricular Unit “Curricular Internship” of the Integrated Master's Degree in Pharmaceutical Sciences at the Faculty of Pharmacy of the University of Coimbra, this work contains: the internship report in Pharmaceutical Industry, carried out with the team responsible for Cosmedesk from May 3rd, 2021 to July 30th, 2021; the internship report in Community Pharmacy, carried out at Farmácia S. José, in Coimbra, from January 3rd, 2021 to April 30th, 2021; and the monograph entitled “Senolytics and Senomorphics for the Treatment of Osteoarthritis”. Osteoarthritis (OA) is a common joint degenerating disease that results in loss of quality of life and decline of functional capacities for those affected by it. Cellular senescence, a hallmark of aging, has been linked to OA development and progression. New therapy approaches targeting cellular senescence have been the subject of valuable research. Senolytics lead to the elimination of senescent cells. Senomorphics affect pathways and molecules linked to senescence associated secretory phenotype (SASP). Evidence has shown that senolytic and senomorphic agents are capable of reducing OA pathogenesis and associated symptomatology. However, more research is needed to assess the efficiency, safety, and adverse effects of these drugs. Given the positive results and current lack of disease modifying therapies, senolytics and senomorphics represent a very promising therapeutic approach for the treatment of OA.

Aging and senescence impact CD4 T helper cell (Th) subset differentiation during influenza infection. In the lungs of infected aged mice, there were significantly greater percentages of Th cells expressing the transcription factor FoxP3, indicative of regulatory CD4 T cells (Treg), when compared to young. TGF‐beta levels, which drive FoxP3 expression, were also higher in the bronchoalveolar lavage of aged mice and blocking TGF‐beta reduced the percentage of FoxP3+ Th in aged lungs during influenza infection. Since TGF‐beta can be the product of senescent cells, these were targeted by treatment with senolytic drugs. Treatment of aged mice with senolytics prior to influenza infection restored the differentiation of Th cells in those aged mice to a more youthful phenotype with fewer Th cells expressing FoxP3. In addition, treatment with senolytic drugs induced differentiation of aged Th toward a healing Type 2 phenotype, which promotes a return to homeostasis. These results suggest that senescent cells, via production of cytokines such as TGF‐beta, have a significant impact on Th differentiation., In young mice, CD4 T cells differentiate appropriately in response to influenza infection, generating T helper subsets that participate in the anti‐viral response. This differentiation is aberrant in aged mice, but can be improved when aged mice are treated with senolytics.

Amyotrophic lateral sclerosis (ALS) is a progressive motor neurodegenerative disease that currently has no cure and has few effective treatments. On a cellular level, ALS manifests through significant changes in the proper function of astrocytes, microglia, motor neurons, and other central nervous system (CNS) cells, leading to excess neuroinflammation and neurodegeneration. Damage to the upper and lower motor neurons results in neural and muscular dysfunction, leading to death most often due to respiratory paralysis. A new therapeutic strategy is targeting glial cells affected by senescence, which contribute to motor neuron degeneration. Whilst this new therapeutic approach holds much promise, it is yet to be trialled in ALS-relevant preclinical models and needs to be designed carefully to ensure selectivity. This review summarizes the pathways involved in ALS-related senescence, as well as known senolytic agents and their mechanisms of action, all of which may inform strategies for ALS-focused drug discovery efforts.

Various stresses latently induce cellular senescence that occasionally deteriorates the functioning of surrounding tissues. Nevertheless, little is known about the appearance and function of senescent cells, caused by the implantation of beta-tricalcium phosphate (β-TCP)—used widely in dentistry and orthopedics for treating bone diseases. In this study, two varying sizes of β-TCP granules (&lt, 300 μm and 300–500 μm) were implanted, and using histological and immunofluorescent staining, appearances of senescent-like cells in critical-sized bone defects in the calvaria of Sprague Dawley rats were evaluated. Parallelly, bone formation in defects was investigated with or without the oral administration of senolytics (a cocktail of dasatinib and quercetin). A week after the implantation, the number of senescence-associated beta-galactosidase, p21-, p19-, and tartrate-resistant acid phosphatase-positive cells increased and then decreased upon administrating senolytics. This administration of senolytics also attenuated 4-hydroxy-2-nonenal staining, representing reactive oxygen species. Combining senolytic administration with β-TCP implantation significantly enhanced the bone formation in defects as revealed by micro-computed tomography analysis and hematoxylin-eosin staining. This study demonstrates that β-TCP granules latently induce senescent-like cells, and senolytic administration may improve the bone-forming ability of β-TCP by inhibiting senescence-associated mechanisms.

Systemic deletion of senescent cells leads to robust improvements in cognitive, cardiovascular, and whole‐body metabolism, but their role in tissue reparative processes is incompletely understood. We hypothesized that senolytic drugs would enhance regeneration in aged skeletal muscle. Young (3 months) and old (20 months) male C57Bl/6J mice were administered the senolytics dasatinib (5 mg/kg) and quercetin (50 mg/kg) or vehicle bi‐weekly for 4 months. Tibialis anterior (TA) was then injected with 1.2% BaCl2 or PBS 7‐ or 28 days prior to euthanization. Senescence‐associated β‐Galactosidase positive (SA β‐Gal+) cell abundance was low in muscle from both young and old mice and increased similarly 7 days following injury in both age groups, with no effect of D+Q. Most SA β‐Gal+ cells were also CD11b+ in young and old mice 7‐ and 14 days following injury, suggesting they are infiltrating immune cells. By 14 days, SA β‐Gal+/CD11b+ cells from old mice expressed senescence genes, whereas those from young mice expressed higher levels of genes characteristic of anti‐inflammatory macrophages. SA β‐Gal+ cells remained elevated in old compared to young mice 28 days following injury, which were reduced by D+Q only in the old mice. In D+Q‐treated old mice, muscle regenerated following injury to a greater extent compared to vehicle‐treated old mice, having larger fiber cross‐sectional area after 28 days. Conversely, D+Q blunted regeneration in young mice. In vitro experiments suggested D+Q directly improve myogenic progenitor cell proliferation. Enhanced physical function and improved muscle regeneration demonstrate that senolytics have beneficial effects only in old mice., Senolytics improve muscle regeneration in old mice, while providing no benefit in young mice. Old mice display more satellite cells, reduced inflammation, a lower senescent cell burden, and increased gene expression of bioenergetic pathways relative to untreated old mice.

Senotherapeutics are new drugs that can modulate senescence phenomena within tissues and reduce the onset of age-related pathologies. Senotherapeutics are divided into senolytics and senomorphics. The senolytics selectively kill senescent cells, while the senomorphics delay or block the onset of senescence. Metformin has been used to treat diabetes for several decades. Recently, it has been proposed that metformin may have anti-aging properties as it prevents DNA damage and inflammation. We evaluated the senomorphic effect of 6 weeks of therapeutic metformin treatment on the biology of human adipose mesenchymal stromal cells (MSCs). The study was combined with a proteome analysis of changes occurring in MSCs’ intracellular and secretome protein composition in order to identify molecular pathways associated with the observed biological phenomena. The metformin reduced the replicative senescence and cell death phenomena associated with prolonged in vitro cultivation. The continuous metformin supplementation delayed and/or reduced the impairment of MSC functions as evidenced by the presence of three specific pathways in metformin-treated samples: 1) the alpha-adrenergic signaling, which contributes to regulation of MSCs physiological secretory activity, 2) the signaling pathway associated with MSCs detoxification activity, and 3) the aspartate degradation pathway for optimal energy production. The senomorphic function of metformin seemed related to its reactive oxygen species (ROS) scavenging activity. In metformin-treated samples, the CEBPA, TP53 and USF1 transcription factors appeared to be involved in the regulation of several factors (SOD1, SOD2, CAT, GLRX, GSTP1) blocking ROS.

Significance Cellular growth arrest, associated with ‘senescence’, helps to safeguard against the accumulation of DNA damage which is often recognized as the underlying mechanism of a wide variety of age-related pathologies including cancer. Cellular senescence has also been described as a ‘double-edged sword’. In cancer, for example, the creation of an immune-suppressive milieu by senescent tumor cells through the senescence-associated secretory phenotype contributes toward carcinogenesis and cancer progression. Recent advances The potential for cellular senescence to confer multi-faceted effects on tissue fate has led to a rejuvenated interest in its landscape and targeting. Interestingly, redox pathways have been described as both triggers and propagators of cellular senescence, leading to intricate cross-links between both pathways. Critical issues In this review, we describe the mechanisms driving cellular senescence, the interface with cellular redox metabolism as well as the role that chemotherapy-induced senescence plays in secondary carcinogenesis. Notably, the role that anti-apoptotic proteins of the Bcl-2 family play in inducing drug resistance via mechanisms that involve senescence induction. Future directions Though the therapeutic targeting of senescent cells as cancer therapy remains in its infancy, we summarize the current development of senotherapeutics, including recognized senotherapies, as well as the repurposing of drugs as senomorphic/senolytic candidates.

Male late-onset hypogonadism is an age-related disease, the core mechanism of which is dysfunction of senescent Leydig cells. Recent studies have shown that elimination of senescent cells can restore proper homeostasis to aging tissue. In the present study, we found that the fork head box O (FOXO) transcription factor FOXO4 was specially expressed in human Leydig cells and that its translocation to the nucleus in the elderly was related to decreased testosterone synthesis. Using hydrogen peroxide-induced senescent TM3 Leydig cells as an in vitro model, we observed that FOXO4 maintains the viability of senescent Leydig cells and suppresses their apoptosis. By disrupting the FOXO4-p53 interaction, FOXO4-DRI, a specific FOXO4 blocker, selectively induced p53 nuclear exclusion and apoptosis in senescent Leydig cells. In naturally aged mice, FOXO4-DRI improved the testicular microenvironment and alleviated age-related testosterone secretion insufficiency. These findings reveal the therapeutic potential of FOXO4-DRI for the treatment of male late-onset hypogonadism.

The uterine fibrosis contributes to gestational outcomes. Collagen deposition in the uterus is related to uterine aging. Senolytic therapies are an option for reducing health complications related to aging. We investigated effects of aging and the senolytic drug combination of dasatinib plus quercetin (D+Q) on uterine fibrosis. Forty mice, 20 young females (03-months) and 20 old females (18-months), were analyzed. Young (Y) and old (O) animals were divided into groups of 10 mice, with one treatment (T) group (YT and OT) and another control © group (YC and OC). Comparative analysis of Pi3k/Akt1/mTor and p53 gene expression and related microRNAs (miR34a, miR34b, miR34c, miR146a, miR449a, miR21a, miR126a, and miR181b) among groups was performed to test effects of age and treatment on collagen deposition pathways. Aging promoted downregulation of the Pi3k/Akt1/mTor signaling pathway (P = 0.005, P = 0.031, and P = 0.028, respectively) as well as a reduction in expression of miR34c (P = 0.029), miR126a (P = 0.009), and miR181b (P = 0.007). D+Q treatment increased p53 gene expression (P = 0.041) and decreased miR34a (P = 0.016). Our results demonstrate a role for the Pi3k/Akt1/mTor signaling pathway in uterine aging and suggest for the first time a possible anti-fibrotic effect in the uterus of D+Q senolytic therapy.

Aging is the most important single risk factor for many chronic diseases such as cancer, metabolic syndrome, and neurodegenerative disorders. Targeting aging itself might, therefore, be a better strategy than targeting each chronic disease individually for enhancing human health. Although much should be achieved for completely understanding the biological basis of aging, cellular senescence is now believed to mainly contribute to organismal aging via two independent, yet not mutually exclusive mechanisms: on the one hand, senescence of stem cells leads to exhaustion of stem cells and thus decreases tissue regeneration. On the other hand, senescent cells secrete many proinflammatory cytokines, chemokines, growth factors, and proteases, collectively termed as the senescence-associated secretory phenotype (SASP), which causes chronic inflammation and tissue dysfunction. Much effort has been recently made to therapeutically target detrimental effects of cellular senescence including selectively eliminating senescent cells (senolytics) and modulating a proinflammatory senescent secretome (senostatics). Here, we discuss current progress and limitations in understanding molecular mechanisms of senolytics and senostatics and therapeutic strategies for applying them. Furthermore, we propose how these novel interventions for aging treatment could be improved, based on lessons learned from cancer treatment.

During organism aging, the process of cellular senescence is triggered by critical stressors such as DNA damage, oncogenes, oxidative stress, and telomere erosion, and vascular cells are not exempted. Senescent cells stop proliferating but remain metabolically active producing pro-inflammatory signals in the environment collectively named senescence-associated secretory phenotype (SASP) that contribute to the amplification of the response to the neighbor and distant cells. Although the shift toward senescence is protective against tumors and needed during wound healing, the accumulation of senescent cells during aging due to an impairment of the immune system deputed to their clearance, can predispose to diseases of the cardiovascular system such as atherosclerosis. In this short review, we describe the main features of senescence of endothelial and smooth muscle cells and focus on the role non-coding RNAs of the microRNAs class in controlling this process. Finally, we discuss the potential of new strategies based on senescence removal in counteracting vascular disease burden.

Ageing and diabetes lead to similar organ dysfunction that is driven by parallel molecular mechanisms, one of which is cellular senescence. The abundance of senescent cells in various tissues increases with age, obesity and diabetes. Senescent cells have been directly implicated in the generation of insulin resistance. Recently, drugs that preferentially target senescent cells, known as senolytics, have been described and recently entered clinical trials. In this review, we explore the biological links between ageing and diabetes, specifically focusing on cellular senescence. We summarise the current data on cellular senescence in key target tissues associated with the development and clinical phenotypes of type 2 diabetes and discuss the therapeutic potential of targeting cellular senescence in diabetes. Electronic supplementary material The online version of this article (10.1007/s00125-019-4934-x) contains a slideset of the figures for download, which is available to authorised users.

Purpose of reviewSenescent cells have recently been identified as key players in the development of metabolic dysfunction. In this review, we will highlight recent developments in this field and discuss the concept of targeting these cells to prevent or treat cardiometabolic diseases.Recent findingsEvidence is accumulating that cellular senescence contributes to adipose tissue dysfunction, presumably through induction of low-grade inflammation and inhibition of adipogenic differentiation leading to insulin resistance and dyslipidaemia. Senescent cells modulate their surroundings through their bioactive secretome and only a relatively small number of senescent cells is sufficient to cause persistent physical dysfunction even in young mice. Proof-of-principle studies showed that selective elimination of senescent cells can prevent or delay the development of cardiometabolic diseases in mice.SummaryThe metabolic consequences of senescent cell accumulation in various tissues are now unravelling and point to new therapeutic opportunities for the treatment of cardiometabolic diseases.