Life Span Of Animals Research Articles

The Effect of Donepezil Hydrochloride in the Twitcher Mouse Model of Krabbe Disease.

Krabbe disease (KD) is a rare demyelinating disorder characterized by demyelination caused by mutations in the GALC gene, resulting in toxic accumulation of psychosine. Psychosine has been identified as detrimental to oligodendrocytes, leading to demyelination through diverse hypothesized pathways. Reducing demyelination is essential to maintain neurological function in KD; however, therapeutic interventions are currently limited. Acetylcholinesterase inhibitors (AChEi) are commonly used for symptomatic management of Alzheimer's Disease and are suggested to have potential disease-modifying effects, including regulating myelin state. In particular, donepezil, an AChEi, has demonstrated promising effects in cellular and animal models, including promotion of the expression of myelin-related genes and reduction of glial cell reactivity. This drug also acts as an agonist for sigma-1 receptors (Sig-1R), which are implicated in demyelination diseases. In the context of drug repurposing, here, we demonstrate that administration of donepezil has protective effects in the twitcher mouse model of KD. We provide data showing that donepezil preserves myelin and reduces glial cell reactivity in the brains of twitcher mice. Moreover, donepezil also improves behavioral phenotypes and increases lifespan in twitcher animals. These findings suggest that donepezil, with its dual activity as an AChE inhibitor and Sig-1R agonist, may hold promise as a therapeutic candidate for demyelinating diseases, including KD.

Tap Water Shorts the Lifespan of Mice with Prolonged Exposure to Fractionated γ-Radiation

Assessing the role of social factors in the formation of radioresistance in chronic exposure and finding ways to increase it are important for understanding the mechanisms of the damaging effects of radiation and developing practical methods for reducing radiation risk in professionals exposed to ionizing radiation and patients undergoing radiation therapy. In this work, we investigated the ability to influence the lifespan of animals exposed to γ-radiation fractionally for a long time by replacing drinking water from tap water to distilled water. Female ICR mice (CD-1) were exposed to total 60Co γ radiation weekly in fractions for 33 weeks starting at 9 weeks of age. The dose of a single irradiation was 50 mGy, the average dose rate was 2 mGy/sec. The total radiation dose was 1.65 Gy. Control non-irradiated mice and irradiated animals were divided into 2 groups. The first received tap water, and the second received distilled water throughout the experiment. Non-irradiated animals kept on tap water showed a statistically insignificant (log-rank test, p = 0.483) reduction in average life expectancy compared to mice kept on distilled water. In animals after exposure to 60Co γ-radiation, a statistically significant (p = 0.0013) decrease in life expectancy was noted when kept on tap water and statistically insignificant (p = 0.1511) when kept on distilled water. Tap water and irradiation showed a clear synergy with a combined effect on the body of mice, expressed in a more than threefold decrease in the period of post-radiation shortening of life expectancy. Distilled water reduced the rate of death of irradiated animals and modified the rate of death of non-irradiated animals. Our data demonstrate that the reduction in life expectancy of mice kept on tap water caused by long-term fractionated irradiation can be reduced when animals are kept on distilled water.

The neurotrophic factor MANF regulates autophagy and lysosome function to promote proteostasis in Caenorhabditis elegans

The conserved mesencephalic astrocyte-derived neurotrophic factor (MANF) is known for protecting dopaminergic neurons and functioning in various other tissues. Previously, we showed that Caenorhabditis elegans manf-1 null mutants exhibit defects such as increased endoplasmic reticulum (ER) stress, dopaminergic neurodegeneration, and abnormal protein aggregation. These findings suggest an essential role for MANF in cellular processes. However, the mechanisms by which intracellular and extracellular MANF regulate broader cellular functions remain unclear. We report a unique mechanism of action for MANF-1 that involves the transcription factor HLH-30/TFEB-mediated signaling to regulate autophagy and lysosomal function. Multiple transgenic strains overexpressing MANF-1 showed extended lifespan of animals, reduced protein aggregation, and improved neuronal survival. Using fluorescently tagged MANF-1, we observed tissue-specific localization of the protein, which was dependent on the ER retention signal. Further subcellular analysis showed that MANF-1 localizes within cells to the lysosomes and utilizes the endosomal pathway. Consistent with the lysosomal localization, our transcriptomic study of MANF-1 and analyses of autophagy regulators demonstrated that MANF-1 promotes proteostasis by regulating autophagic flux and lysosomal activity. Collectively, our findings establish MANF as a critical regulator of stress response, proteostasis, and aging.

Anti-tumor effects of recombinant human cyclophilin A combined with immune checkpoint inhibitors in the experimental model of melanoma B16 in vivo

Introduction. Immune checkpoint inhibitors have an exceptional position in cancer immunotherapy. Currently, anti-CTLA-4 (cytotoxic T-lymphocyte-associated protein 4) and anti-PD-1/PD-L1 (PD-1 – programmed cell death 1, PD-L1 – programmed death 1 ligand 1) therapies are most widely applied in clinical practice. Still, immune checkpoint inhibitors therapy is not always successful, and multiple studies have indicated that it should be combined with other immunotherapeutic strategies, including cytokines. Secreted cyclophilin A (CypA) could be of particular interest in this respect. Previously, we showed that recombinant human CypA (rhCypA) had pleiotropic immunostimulatory activity and anti-tumor effects. Studies of rhCypA as an anti-cancer factor pointed to its potential use in cancer chemoimmunotherapy and combination immunotherapy.Aim. To evaluate anti-tumor effects of combined immunotherapy using rhCypA and immune checkpoint inhibitors in the mouse model of melanoma B16 in vivo.Materials and methods. C57BL/6 mice were subcutaneously transplanted with melanoma B16. On days 6 and 9 posttumor transplantation, monoclonal antibodies to PD-1, PD-L1 and programmed cell death 1 ligand 2 (PD-L2), CTLA-4, lymphocyte-activation gene 3 (LAG-3), or CD276 were intravenously injected into mice at a dose of 100 μg/mouse. RhCypA was injected s/c on days 6–10 post-tumor transplantation at a dose of 100 μg/mouse. The therapeutic effects of combined immunotherapy were evaluated by melanoma B16 growth dynamics and the survival of tumor-bearing mice.Results. In combination with anti-CTLA-4 monoclonal antibodies, rhCypA had the most distinct and prolonged synergic anti-tumor effects until day 19 post-immunotherapy, with an increase in animal lifespan of 70 %. When used with anti-LAG-3 monoclonal antibodies, rhCypA exhibited a synergic therapeutic effect by day 12 post-therapy. Combination of rhCypA with anti-PD-L1 or anti-CD276 monoclonal antibodies had short-term synergic effects until day 5 after therapy. Recombinant human CypA impeded the anti-tumor effects of dual anti-PD-1 + anti-LAG-3 therapy.Conclusion. Our findings pointed out that rhCypA could significantly improve therapeutic effects of individual immune checkpoint inhibitors. Therefore, rhCypA could be potentially proposed as a component of combined anti-tumor immunotherapy.

Targeting glioblastoma with a brain-penetrant drug that impairs brain tumor stem cells via NLE1-Notch1 complex.

Brain tumor stem cells (BTSCs) are a population of self-renewing malignant stem cells that play an important role in glioblastoma tumor hierarchy and contribute to tumor growth, therapeutic resistance, and tumor relapse. Thus, targeting of BTSCs within the bulk of tumors represents a crucial therapeutic strategy. Here, we report that edaravone is a potent drug that impairs BTSCs in glioblastoma. We show that edaravone inhibits the self-renewal and growth of BTSCs harboring a diverse range of oncogenic mutations without affecting non-oncogenic neural stem cells. Global gene expression analysis revealed that edaravone significantly alters BTSC transcriptome and attenuates the expression of a large panel of genes involved in cell cycle progression, stemness, and DNA repair mechanisms. Mechanistically, we discovered that edaravone directly targets Notchless homolog 1 (NLE1) and impairs Notch signaling pathway, alters the expression of stem cell markers, and sensitizes BTSC response to ionizing radiation (IR)-induced cell death. Importantly, we show that edaravone treatment in preclinical models delays glioblastoma tumorigenesis, sensitizes their response to IR, and prolongs the lifespan of animals. Our data suggest that repurposing of edaravone is a promising therapeutic strategy for patients with glioblastoma.

The impact of host genetics on microbe assemblages in three types of mrigal carp (Cirrhinus mrigala)

Host–microbiota interactions are molecular and physical interactions between the microbiota and the host that play significant roles in the lifespan of animals. In the present study, two types of gynogenetic mrigal carp (GMCC and GMCW) and the original maternal mrigal carp (MC) were used as a models to investigate host–microbiota interactions. The two types of gynogenetic mrigal carps showed faster growth and better cold tolerance than the MC fish. Compared to those in MC, a large number of goblet cells and higher activity of cellulase and pepsin were detected in the intestine of gynogenetic fish. The composition and abundance of the microbial communities significantly differed among the three types of mrigal carp and water, with Proteobacteria, Firmicutes and Chloroflexi being the most dominant microbes in the GMCC, GMCW and MC fish, respectively. Pseudomonas, Lactococcus and Defluviicoccus were the biomarker genera in the GMCC, GMCW and MC fish. Network analysis revealed no relationships between fish and water, but the dominant genera was positively correlated with the abundance of certain enzymes. Functional analysis revealed the dominant genera associated with amino acid metabolism, fatty acid metabolism and bile acid biosynthesis. Our results suggested that host genetics may affected gut microbe assembly and that the specific metabolic functions of gut microbes may contribute to growth performance through the microbe-gut-liver axis.

A biological age based on common clinical markers predicts health trajectory and mortality risk in dogs.

Predicting aging trajectories through biomarkers of biological aging can guide interventions that optimize healthy lifespan in humans and companion animals. Differences in physiology, genetics, nutrition, and lifestyle limit the generalization of such biomarkers and may therefore require species-specific algorithms. Here, we compared correlations of standard clinical blood parameters with survival probability in humans with those of the two most common mammalian companion animals, cats and dogs, and highlighted universal and species-specific relationships. Based on this comparative analysis, we generated and validated an algorithm that predicts biological age in canines using a longitudinal dataset with health records, blood count, and clinical chemistry from 829 dogs spanning over 12years. Positive deviations of biological from chronological age (AgeDev) measured by this composite score significantly correlated with a decreased survival probability (hazard ratio = 1.75 per 1year of AgeDev, p = 3.7e - 06). Importantly, in nearly half of the dogs whose biological age was accelerated by more than 1year, none or only a single individual marker scored outside its respective reference range, suggesting practical applications for the detection of unfavorable health trajectories. Analyzing samples from a unique 14-year life-long diet restriction study, we show that restricted caloric intake lowers biological age, an effect that can be quantified at midlife years before a difference in survival is observed. Thus, a biological age clock based on clinical blood tests predicts the health trajectories of dogs for use in research and veterinary practice.

167 Using ‘omics’ to optimize nutrition and health outcomes

Abstract It is clear that diet is linked with health outcomes, yet we are still far from fully understanding the impact of diet on systemic metabolic health. In the new era of ‘omics’ technology, the ability to optimize nutrition across the lifespan of companion animals is within reach. We have been using ‘omics’ technologies to understand how changes in diet composition impact metabolism using a neonatal piglet model. By measuring the composition of sow milk over the first week of lactation, we created an optimized pig milk replacer, and studied the impact of varying the whey protein composition of the milk replacer using a combination of metabolomics on blood, urine, liver, and brain tissue, as well as transcriptomics of intestinal, liver and brain tissue. Our results revealed a substantial impact of the type of whey protein on piglet metabolism that included differences in cortisol, blood and tissue amino acid profiles, and immunity. This work paves the way for additional studies to optimize animal nutrition in the neonatal period and beyond.

Realistic Aspects of Cardiac Ultrasound in Rats: Practical Tips for Improved Examination.

Echocardiography is a reliable and non-invasive method for assessing cardiac structure and function in both clinical and experimental settings, offering valuable insights into disease progression and treatment efficacy. The successful application of echocardiography in murine models of disease has enabled the evaluation of disease severity, drug testing, and continuous monitoring of cardiac function in these animals. However, there is insufficient standardization of echocardiographic measurements for smaller animals. This article aims to address this gap by providing a guide and practical tips for the appropriate acquisition and analysis of echocardiographic parameters in adult rats, which may also be applicable in other small rodents used for scientific purposes, like mice. With advancements in technology, such as ultrahigh-frequency ultrasonic transducers, echocardiography has become a highly sophisticated imaging modality, offering high temporal and spatial resolution imaging, thereby allowing for real-time monitoring of cardiac function throughout the lifespan of small animals. Moreover, it allows the assessment of cardiac complications associated with aging, cancer, diabetes, and obesity, as well as the monitoring of cardiotoxicity induced by therapeutic interventions in preclinical models, providing important information for translational research. Finally, this paper discusses the future directions of cardiac preclinical ultrasound, highlighting the need for continued standardization to advance research and improve clinical outcomes to facilitate early disease detection and the translation of findings into clinical practice.

AI-aided cardiovascular disease diagnosis in cattle from retinal images: Machine learning vs. deep learning models

Cardiovascular diseases (CVD) in animals can severely impact the heart and circulatory systems, like those in humans. Early diagnosis and treatment are crucial for improving animal welfare and lifespan. Traditional diagnostic methods face challenges such as insufficient anamnesis information, high costs of biochemical and hematological tests, and increasing data complexity. This study aims to address these issues by developing AI-based diagnostic systems for fast and accurate CVD diagnosis in cattle using retinal images. A total of 1118 retinal images from 100 cattle were collected, with 52 diagnosed with CVD and 48 as non-CVD. The dataset is publicly available on Kaggle. We evaluated three machine learning methods (Extreme Learning Machine, K-Nearest Neighbors, and Support Vector Machine) and four deep learning models (DenseNet201, ResNet101, SqueezeNet, and InceptionV3) for their diagnostic capabilities. ResNet101 emerged as the most effective model, achieving an accuracy of 96.1 ± 3.15 %, sensitivity of 97.3 ± 2.96 %, specificity of 94.9 ± 4.07 %, and an F1-score of 96.4 ± 0.03. This study demonstrates that AI-based systems, particularly deep learning models, can significantly improve the accuracy of CVD diagnosis in animals, marking a critical advancement in veterinary healthcare.

The NLRP3 inhibitor Dapansutrile improves the therapeutic action of lonafarnib on progeroid mice.

The role of the inflammasomes in aging and progeroid syndromes remain understudied. Recently, MCC950, a NLRP3 inhibitor, was used in Zmpste24-/- mice to ameliorate the phenotypes. However, the safety of MCC950 was questioned due to liver toxicity observed in humans. Nevertheless, inhibition of the inflammasomes would be a beneficial therapy for progeria. Here, we show that OLT1177 (dapansutrile), other NLRP3 inhibitor, improved cellular and animal phenotypes using progeroid fibroblasts and a LmnaG609G/G609G mouse model. In both cases dapansutrile reduced progerin accumulation, NLRP3-inflammasome activation and secretory phenotype of senescence, extended the lifespan of progeroid animals, preserved bodyweight, and reduced kyphosis, inflammation, and senescence. Interestingly, dapansutrile further improved the effect of lonafarnib, the only FDA-approved drug for the progeria. The combination of both drugs reduced the inflammation and senescence, extended survival and ameliorated various progeroid defects both invitro and invivo, compared with treatment using lonafarnib alone. These findings and the safety of dapansutrile demonstrated in several clinical trials proposes it as a possible co-adjuvant treatment with lonafarnid in HGPS.

Engineered deletions of HIV replicate conditionally to reduce disease in nonhuman primates.

Antiviral therapies with reduced frequencies of administration and high barriers to resistance remain a major goal. For HIV, theories have proposed that viral-deletion variants, which conditionally replicate with a basic reproductive ratio [R0] > 1 (termed "therapeutic interfering particles" or "TIPs"), could parasitize wild-type virus to constitute single-administration, escape-resistant antiviral therapies. We report the engineering of a TIP that, in rhesus macaques, reduces viremia of a highly pathogenic model of HIV by >3log10 following a single intravenous injection. Animal lifespan was significantly extended, TIPs conditionally replicated and were continually detected for >6 months, and sequencing data showed no evidence of viral escape. A single TIP injection also suppressed virus replication in humanized mice and cells from persons living with HIV. These data provide proof of concept for a potential new class of single-administration antiviral therapies.

Cysteine protease cathepsin B promotes lysosome integrity to extend the lifespan of alternative day fasting worms.

Alternative day fasting (ADF) has been shown to enhance the lifespan of animals. However, human trials evaluating the efficacy of ADF have only recently emerged, presenting challenges due to the extreme nature of this dietary regimen. To better understand the effects of ADF, we investigated its impact using Caenorhabditis elegans as a model organism. Our findings reveal that ADF extends the lifespan of worms nourished on animal-based protein source, while those fed with plant-based protein as the primary protein source do not experience such benefits. Remarkably, initiating ADF during midlife is sufficient to prolong lifespan, whereas implementation during youth results in developmental damage, and in older age, fails to provide additional extension effects. Furthermore, we discovered that midlife ADF up-regulates the expression of two cysteine protease cathepsin B genes, cpr-2 and cpr-5, which preserve lysosomal integrity and enhance its function in digesting aggregated proteins, as well as enhancing lipid metabolism and ameliorating neurodegenerative disease markers and phenomena during aging. This suggests that midlife ADF has long lasting anti-aging effects and may delay the onset of related diseases, specifically in animals consuming animal-based protein source. These findings offer valuable insights into the effects of ADF and provide guidance for future research and potential applications in individuals.

Embryonic alcohol exposure in zebrafish predisposes adults to cardiomyopathy and diastolic dysfunction.

Fetal alcohol spectrum disorders (FASDs) impact up to 0.8% of the global population. However, cardiovascular health outcomes in adult patients, along with predictive biomarkers for cardiac risk stratification, remain unknown. Our aim was to utilize a longitudinal cohort study in an animal model to evaluate the impact of embryonic alcohol exposure (EAE) on cardiac structure, function, and transcriptional profile across the lifespan. Using zebrafish, we characterized the aftereffects of embryonic alcohol exposure (EAE) in adults binned by congenital heart defect (CHD) severity. Chamber sizes were quantified on dissected adult hearts to identify structural changes indicative of cardiomyopathy. Using echocardiography, we quantified systolic function based on ejection fraction and longitudinal strain, and diastolic function based on ventricular filling dynamics, ventricular wall movement, and estimated atrial pressures. Finally, we performed RNA sequencing on EAE ventricles and assessed how differentially expressed genes (DEGs) correlated with cardiac function. Here, we demonstrate that embryonic alcohol exposure (EAE) causes cardiomyopathy and diastolic dysfunction through persistent alterations to ventricular wall structure and gene expression. Following abnormal ventricular morphogenesis, >30% of all EAE adults developed increased atrial-to-ventricular size ratios, abnormal ventricular filling dynamics, and reduced myocardial wall relaxation during early diastole despite preserved systolic function. RNA sequencing of the EAE ventricle revealed novel and heart failure-associated genes (slc25a33, ankrd9, dusp2, dusp4, spry4, eya4, and edn1) whose expression levels were altered across the animal's lifespan or correlated with the degree of diastolic dysfunction detected in adulthood. Our study identifies EAE as a risk factor for adult-onset cardiomyopathy and diastolic dysfunction, regardless of CHD status, and suggests novel molecular indicators of adult EAE-induced heart disease.

Suppression of autophagy induces senescence in the heart.

Aging is a critical risk factor for heart disease, including ischemic heart disease and heart failure. Cellular senescence, characterized by DNA damage, resistance to apoptosis and the senescence-associated secretory phenotype (SASP), occurs in many cell types, including cardiomyocytes. Senescence precipitates the aging process in surrounding cells and the organ through paracrine mechanisms. Generalized autophagy, which degrades cytosolic materials in a non-selective manner, is decreased during aging in the heart. This decrease causes deterioration of cellular quality control mechanisms, facilitates aging and negatively affects lifespan in animals, including mice. Although suppression of generalized autophagy could promote senescence, it remains unclear whether the suppression of autophagy directly stimulates senescence in cardiomyocytes, which, in turn, promotes myocardial dysfunction in the heart. We addressed this question using mouse models with a loss of autophagy function. Suppression of general autophagy in cardiac-specific Atg7 knockout ( Atg7 cKO) mice caused accumulation of senescent cardiomyocytes. Induction of senescence via downregulation of Atg7 was also observed in chimeric Atg7 cardiac-specific KO mice and cultured cardiomyocytes in vitro , suggesting that the effect of autophagy suppression upon induction of senescence is cell autonomous. ABT-263, a senolytic agent, reduced the number of senescent myocytes and improved cardiac function in Atg7 cKO mice. Suppression of autophagy and induction of senescence were also observed in doxorubicin-treated hearts, where activation of autophagy alleviated senescence in cardiomyocytes and cardiac dysfunction. These results suggest that suppression of general autophagy directly induces senescence in cardiomyocytes, which in turn promotes cardiac dysfunction.

Predictive Models of Life Span in Old Female Mice Based on Immune, Redox, and Behavioral Parameters.

The development of mathematical models capable of predicting the lifespan of animals is growing. However, there are no studies that compare the predictive power of different sets of parameters depending on the age of the animals. The aim of the present study is to test whether mathematical models for life span prediction developed in adult female mice based on immune, redox, and behavioral parameters can predict life span in old animals and to develop new models in old mice. For this purpose, 29 variables, including parameters of immune function, redox state, and behavioral ones, were evaluated in old female Swiss mice (80 ± 4 weeks). Life span was registered when they died naturally. Firstly, we observed that the models developed in adults were not able to accurately predict the life span of old mice. Therefore, the immunity (adjusted R2 = 73.6%), redox (adjusted R2 = 46.5%), immunity-redox (adjusted R2 = 96.4%), and behavioral (adjusted R2 = 67.9%) models were developed in old age. Finally, the models were validated in another batch of mice. The developed models in old mice show certain similarities to those in adults but include different immune, redox, and behavioral markers, which highlights the importance of age in the prediction of life span.

Antihypoxic effect of almid-containing metal-complex compounds in the experiment

BACKGROUND: To increase resistance to hypoxia, various methods of hypoxic training, mental effects, and use of pharmacological antihypoxants are employed.
 AIM: To test new metal-complex compounds containing the antihypoxant almid in mice under conditions of acute hypoxia to determine their protective properties.
 MATERIALS AND METHODS: In the first stage of the study, four new metal-complex compounds of magnesium, calcium, titanium, and vanadium containing the antihypoxant almid were screened in experiments on mice (n = 550) under acute hypoxic conditions with hypercapnia. The antihypoxants almid and amtizole were used as comparison substances. Acute hypoxia was induced by placing the animals in pharmacy glasses with a volume of 0.25 L with closed lapped stoppers. The substances were administered intraperitoneally at doses of 25, 50, and 100 mg/kg previously dissolved in 0.3 mL of NaCl solution. The incubation period was 60 min. The antihypoxic effect was considered confirmed if the lifespan increased by ≥20%. “Lifespan” refers to the time interval from the moment the mice were placed in a pharmacy glass to the development of the first agonal inhalation, after which the animals were quickly removed to preserve life. The rectal temperature of the animals was measured before the introduction of substances, immediately before being exposed to acute hypoxic conditions with hypercapnia, and after removal. Twenty-four hours after the first stage of the experiment, mice of the control group and mice that proved their ability to resist acute hypoxia with hypercapnia were repeatedly exposed to acute hypoxic conditions with hypercapnia after the use of substances.
 RESULTS: A distinct antihypoxic effect exceeding the effectiveness of the comparison substances was obtained only in one substance—πQ2460 with titanium as a metal-complexing agent—and a ligand in the form of fumaric acid. After the administration of πQ2460, a dose-dependent decrease in rectal temperature was observed in mice. The lifespan of animals increased with an increase in the dosage of πQ2460, i.e., by 43.9%, 103.1%, and 152.8% for doses of 25, 50, and 100 mg/kg, respectively. The results of the second stage of the experiment confirmed the stable protective effect of πQ2460 but with an equalization of the effect of the studied doses, which increased the lifespan under acute hypoxic conditions with hypercapnia to an average of 60–70 min (control group, 40.5 min).
 CONCLUSION: Among the compounds containing the antihypoxant almid in the complex molecule, πQ2460 (metal, titanium; ligand, fumaric acid) was found to have a stable protective dose-dependent effect on the development of acute hypoxia with hypercapnia in mice exceeding that for almid and the reference antihypoxant amtizole. The antihypoxic effect of πQ2460 persisted 24 h after its administration but leveled off for the studied doses—25, 50, and 100 mg/kg. Considering the data obtained during the comparison of the indicators of resistance to acute hypoxia in the control group, a hypothesis was proposed regarding the possibility of forming a preconditioning effect in animals from the primary effects of acute hypoxia.

Regulation of Aging Processes: A Perspective of Dietary Restriction Models

The moderate restriction of dietary energy intake (dietary restriction: DR) extends the lifespan and health span of various laboratory animals, suggesting that it delays the aging process inherent in many animal species. Attenuated growth hormone and insulin-like growth factor-1 (IGF-1) signaling caused by mutations also increases the lifespan of mice, even those allowed to feed freely. In nematodes, the Daf16, mammalian Forkhead box O (FoxO) transcription factor, was shown to be required for lifespan extension in response to reduced IGF-1 signaling. Because DR also decreases the plasma concentration of IGF-1 in mammals, the IGF-1-FoxO axis may play a central role in the lifespan extension effect of DR and, thus, retardation of aging. Studies using knockout mice under DR conditions revealed the importance of FoxO1 and nuclear factor erythroid-derived 2-like 2 (Nrf2) in tumor suppression, and FoxO3 in lifespan extension. Human genomic studies also identified a strong association between a FOXO3 single nucleotide polymorphism and longevity. The aging mechanism is the most important risk factor for disease and frailty in aging humans. Therefore, further research on the application of DR to humans, the development of compounds and drugs that mimic the effects of DR, and mechanisms underlying FOXO3 polymorphisms for longevity is highly relevant to extending the human health span.

Abstract 1334: Evaluation of NK cell combination therapies in mouse models of cancer

Abstract Adoptive immunotherapy with natural killer (NK) cells has emerged as a promising innovative approach against hematological malignancies and solid tumors. To enhance the functional aspects of NK cells and to achieve stronger, sustained anti-tumor responses, combination strategies are under development. They are focused on optimization of NK cell potency, persistence and tumor targeting using monoclonal antibodies, multi-specific NK cell engagers and immune modulators like cytokines. SAR445419 is a universal off-the-shelf allogeneic human NK cell (hNK) product made using Sanofi’s proprietary platform with potential broad application across hematologic and solid tumor indications. We evaluated the therapeutic potential of these NK cells in combination with internal assets and standard of care treatments in preclinical mouse models. The studies were performed in immunodeficient NOG mouse strains transgenic for hIL-15, supporting long-term engraftment of functional hNK cells. We demonstrated the therapeutic advantage of NK cell combination with an anti-CD20 monoclonal antibody (mAb) in a disseminated lymphoma model. We also reported prolonged lifespan of leukemia-bearing animals treated with NK cells and pegenzileukin, a PEGylated non-alpha rhIL-2 variant engineered to preferentially bind to the IL-2 βγ receptors and promote NK cell function. The anti-tumor response correlated with pegenzileukin-induced increase in NK cell numbers in the blood. A combination of CD38KO NK cells with an anti-CD38 mAb was also investigated in a model of multiple myeloma (MM). FcγR-KO immunodeficient mice were used in these studies to limit the confounding contribution of residual murine immune cells engaging with the Fc-competent therapeutic antibody and to specifically detect hNK-cell mediated activity. The comparison of CD38KO versus WT NK cell numbers in the blood of animals treated with an anti-CD38 mAb showed a significant decrease in CD38-expressing NK cell count that was mitigated by the genetic deletion of CD38. Obtained results suggest that CD38KO NK cells are resistant to anti-CD38 mAb-mediated fratricide and provide a rationale for the combination of CD38KO NK cells with anti-an CD38 mAb against MM. Overall, these preclinical in vivo studies have a pivotal role in the evaluation of NK cell combination therapies against cancer and reveal their therapeutic potential. Citation Format: Katarzyna Franciszkiewicz, Pauline Rettman, Beatrice Gauthier, Laurence Noblet, Celine Nicolazzi, Andre Kunert, Rob Igarashi, Loreley Calvet, Valeria Fantin, Sukhvinder Sidhu. Evaluation of NK cell combination therapies in mouse models of cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1334.

Nutraceutical supplementation increases mobility in aged captive non-domesticated felids.

Musculoskeletal diseases (MSDs) are an increasing issue as the lifespan of captive animals increases. Extracts of green-lipped mussels have been linked to alleviation of MSDs in domestic carnivores. Understanding their efficacy in non-domestic felids could provide another tool to improve the welfare of aged individuals in collections. A within-subject study design quantified steps per minute in each of 18 cats of 13 species before and after the addition of a nutraceutical containing green-lipped mussel extract (Antinol) to their diets. The age structure of four commonly kept subspecies of non-domestic cats was quantified to provide a demographic context to the need for managing aged individuals. Each of the 18 cats exhibited a higher number of steps per minute after the addition of Antinol to their diet. At the group level, a paired t-test showed that the step rate was significantly increased after the addition of Antinol to the diet. While our results showed a strong significant increase in step rate following Antinol supplementation, further studies that incorporate a placebo, more individuals and more detailed metrics of mobility would provide a more detailed evidence base for practitioners. Nutraceuticals may yield benefits to aged individual felids, including species kept widely in European collections. Their use warrants further, detailed research in collections.