Social enrichment attenuates chemotherapy induced pro-inflammatory cytokine production and affective behavior via oxytocin signaling

Preparation and characterization of Sorafenib nano-emulsion: impact on pharmacokinetics and toxicity; an in vitro and in vivo study

Hepatocellular carcinoma (HCC) ranks as the third leading cause of cancer-related deaths worldwide. Current treatment strategies include surgical resection, liver transplantation, liver-directed therapy, and systemic therapy. Sorafenib (Sor) is the first systemic drug authorized by the US Food and Drug Administration (FDA) for HCC treatment. Nevertheless, the conventional oral administration of Sor presents several limitations: poor solubility, low bioavailability, drug resistance development, and off-target tissue accumulation, leading to numerous adverse effects. Nano-emulsion, a nano-delivery system, is a viable carrier for poorly water-soluble drugs. It aims to enhance drug bioavailability, target organ accumulation, and reduce off-target tissue exposure, thus improving therapeutic outcomes while minimizing side effects. This study formulated Sor nano-emulsion (Sor NanoEm) using the homogenization technique. The resultant nano-emulsion was characterized by particle size (121.75 ± 12 nm), polydispersity index (PDI; 0.310), zeta potential (-12.33 ± 1.34 mV), viscosity (34,776 ± 3276 CPs), and pH (4.38 ± 0.3). Transmission Electron Microscopy exhibited spherical nano-droplets with no aggregation signs indicating stability. Furthermore, the encapsulation of Sor within the nano-emulsion sustained its release, potentially reducing the frequency of therapeutic doses. Cytotoxicity assessments on the HepG2 cell line revealed that Sor NanoEm had a significantly (P < 0.05) more potent cytotoxic effect compared to Sor suspension. Subsequent tests highlighted superior pharmacokinetic parameters and reduced dosage requirements of Sor NanoEm in mice. It exhibited an enhanced safety profile, particularly in behavior, brain, and liver, compared to its suspended form. These findings underscore the enhanced pharmacological and toxicological attributes of Sor Nano-emulsion, suggesting its potential utility in HCC treatment.

Low sucrose diets protect long-term memory and EPA & DHA enriched diets alter insulin resistance in a mouse model of chemotherapy

Chemotherapy-related cognitive impairment (CRCI) and affective symptoms negatively impact quality of life in breast cancer survivors. The aim of this study was to determine the efficacy of high eicosapentaenoic acid + docosahexaenoic acid (EPA+DHA) and low sucrose diets to alleviate these symptoms in a mouse model of chemotherapy. Potential mechanisms involving insulin resistance were explored. We hypothesized that diets enriched in EPA+DHA and low amounts of sucrose would protect against the impact of chemotherapy on measures of CRCI. Female C57Bl/6 mice were randomized to 1 of 4 diets (2% kcal eicosapentaenoic acid + docosahexaenoic acid [EPA+DHA]/high or low sucrose, low omega-3/high or low sucrose) for 6 weeks and treated with two injections of doxorubicin-based chemotherapy or vehicle during week 2 and 4. Behavioral tests were performed 7 days after second injection. Chemotherapy increased serum insulin and decreased body weight, locomotion and exploratory behavior (all p < .05). Low sucrose consumption resulted in better long-term memory regardless of chemotherapy or vehicle injection (p < .05). 2% EPA+DHA consumption lessened insulin resistance (p < .05); however, controlling for body weight attenuated this effect (p = .08). There were no significant differences by diet or injection on liver lipid content; however, liver lipid content was positively correlated with insulin resistance scores (p < .05). Low sucrose diets may protect long-term memory during chemotherapy. The effect of EPA+DHA on insulin resistance and affective side effects during chemotherapy requires further investigation.

[Kaixinsan alleviates adriamycin-induced depression-like behaviors in mice by reducing ferroptosis in the prefrontal cortex]

OBJECTIVE

To investigate the effect of Kaixinsan (KXS, a traditional Chinese medicine formula) for alleviating adriamycin-induced depression-like behaviors in mice bearing breast cancer xenografts and explore the pharmacological mechanism.

METHODS

Forty female BALB/c mice were randomized equally into control group, model group, and low- and high-dose KXS treatment groups, and in the latter 3 groups, mouse models bearing orthotopic breast cancer 4T1 cell xenografts were established and treated with adriamycin along with saline or KXS via gavage. Depression-like behaviors of the mice were assessed using open field test and elevated plus-maze test, and the changes in serum levels of depression-related factors were examined. RNA-seq analysis and transmission electron microscopy were used and ferroptosis-related factors were detected to explore the mechanisms of adriamycin-induced depression and the therapeutic mechanism of KXS. The results were verified in SH-SY5Y cells using ferroptosis inhibitor Fer-1 as the positive control.

RESULTS

KXS significantly alleviated depression-like behaviors and depression-related serological changes induced by adriamycin in the mouse models. RNA-seq results suggested that KXS alleviated chemotherapy-induced depression by regulating oxidative stress, lipid metabolism and iron ion binding in the prefrontal cortex. Pathological analysis and detection of ferroptosis-related factors showed that KXS significantly reduced ferroptosis in the prefrontal cortex of adriamycin-treated mice. In SH-SY5Y cells, both KXS-medicated serum and the ferroptosis inhibitor were capable of attenuating adriamycin-induced cell ferroptosis.

CONCLUSION

KXS alleviates adriamycininduced depression-like behaviors in mice by reducing ferroptosis in the prefrontal cortex of breast cancer-bearing mice.

Association Between Cancer and Cardiovascular Toxicity: A Nationwide Cross-Sectional Study on NHANES 1999-2018

There is a dearth of evidence pertaining to the relationship of cardiovascular disease (CVD) and its subtype with adjudicated cancer, thereby limiting our understanding of the heightened risk of CVD resulting from long-term complications of cancer and its therapies. The aim of this study was to quantify the risks of CVD and its subtypes in adult cancer survivors compared with cancer-free controls in a nationwide cross-sectional study on Continuous National Health and Nutrition Examination Survey (NHANES). We included 44,442 participants ranging in age from 20 to 85 years. Cancer and CVD diagnoses were ascertained via the household questionnaires. The association of cancer status with the risk of CVD and CVD subtype was examined using weighted logistic regression. Stratification analyses were also performed by age, sex, race, marital status, income status, educational level, and hyperlipidemia. The Wald test was used to calculate P-value for interaction. A total of 4178 participants have cancer, while 4829 participants had CVD, respectively. In the multivariable-adjusted model, the cancer was consistently linked to an elevated risk of CVD. Stratification analyses showed that stronger association between cancer status and CVD risk was found in younger adults, non-white, and participants living without a spouse or partner, and without hyperlipidemia. Our study confirmed that cancer participants were strongly linked to living with CVD, independent of traditional cardiovascular risk factors, especially in younger adults, non-white, and participants living without a spouse or partner, and without hyperlipidemia. There exists a pressing requirement to establish effective strategies for the prevention of CVD within this population characterized by a heightened risk.

What happens when the lights are left on? Transcriptomic and phenotypic habituation to light pollution

Artificial light at night (ALAN) is a ubiquitous pollutant worldwide. Exposure can induce immediate behavioral and physiological changes in animals, sometimes leading to severe health consequences. Nevertheless, many organisms persist in light-polluted environments and may have mechanisms of habituating, reducing responses to repeated exposure over time, but this has yet to be tested experimentally. Here, we tested whether zebra finches (Taeniopygia guttata) can habituate to dim (0.3 lux) ALAN, measuring behavior, physiology (oxidative stress and telomere attrition), and gene expression in a repeated measures design, over 6 months. We present evidence of tolerance to chronic exposure, persistent behavioral responses lasting 8 weeks post-exposure, and attenuation of responses to re-exposure. Oxidative stress decreased under chronic ALAN. Changes in the blood transcriptome revealed unique responses to past exposure and re-exposure. Results demonstrate organismal resilience to chronic stressors and shed light on the capacity of birds to persist in an increasingly light-polluted world.

Social enrichment alters the response of brain leukocytes to chemotherapy and tumor development in aged mice

Aging is a risk factor for the development of breast cancer. Foundational science studies have supported associations among neuroinflammation, breast cancer, and chemotherapy, but to date, these associations are based on studies using young adult rodents. The current study examined the neuroinflammatory effects of chemotherapy in aged, tumor-naïve and tumor-bearing mice with or without social enrichment. Mice received two intravenous injections of doxorubicin (A) and cyclophosphamide (C) at a two-week interval. Brain immune cells were enriched/assessed via flow cytometry, seven days following the second chemotherapy injection. Social enrichment enhanced peripheral immune cell trafficking in aged tumor-naive mice treated with AC. Group housed aged tumor bearing mice receiving AC had reduced percentage of IL-6+ monocytes and granulocytes relative to their singly housed counterparts. Notably, group housing aged experimental mice with young cage partners significantly reduced TNF + monocytes, tumor volume, and tumor mass. These data illustrate the importance of social enrichment in attenuating neuroinflammation and are the first to demonstrate that social support with young housing partners reduces tumor growth in aged mice.

Time of day bias for biological sampling in studies of mammary cancer

Despite its demonstrated biological significance, time of day is a broadly overlooked biological variable in preclinical and clinical studies. How time of day affects the influence of peripheral tumors on central (brain) function remains unspecified. Thus, we tested the hypothesis that peripheral mammary cancer tumors alter the transcriptome of immune responses in the brain and that these responses vary based on time of day; we predicted that time of day sampling bias would alter the interpretation of the results. Brain tissues collected at mid dark and mid light from mammary tumor-bearing and vehicle injected mice were analyzed using the Nanostring nCounter immune panel. Peripheral mammary tumors significantly affected expression within the brain of over 100 unique genes of the 770 represented in the panel, and fewer than 25% of these genes were affected similarly across the day. Indeed, between 65 and 75% of GO biological processes represented by the differentially expressed genes were dependent upon time of day of sampling. The implications of time-of-day sampling bias in interpretation of research studies cannot be understated. We encourage considering time of day as a significant biological variable in studies and to appropriately control for it and clearly report time of day in findings.

Physiological and cognitive changes after treatments of cyclophosphamide, methotrexate, and fluorouracil: implications of the gut microbiome and depressive-like behavior

Introduction

Chemotherapy-induced cognitive impairment colloquially referred to as chemobrain is a poorly understood phenomenon affecting a highly variable proportion of patients with breast cancer. Here we investigate the association between anxiety and despair-like behaviors in mice treated with cyclophosphamide, methotrexate, and fluorouracil (CMF) along with host histological, proteomic, gene expression, and gut microbial responses.

Methods

Forced swim and sociability tests were used to evaluate depression and despair-like behaviors. The tandem mass tag (TMT) proteomics approach was used to assess changes in the neural protein network of the amygdala and hippocampus. The composition of gut microbiota was assessed through 16S rRNA gene sequencing. Finally, quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to evaluate changes in intestinal gap junction markers.

Results and discussion

We observed that CMF induced social and despair-like behavior in mice 96 hours following treatment. Proteomic analysis identified changes in various proteins related to progressive neurological disease, working memory deficit, primary anxiety disorder, and gene expression revealing increases in NMDA and AMPA receptors in both the hippocampus and the amygdala because of CMF treatment. These changes finally, we observed immediate changes in the microbial population after chemotherapy treatment, with a notable abundance of Muribaculaceae and Romboutsia which may contribute to changes seen in the gut.

Cell-liposome delivery system based on neuroinflammation to target the amygdala for ameliorating depressive-like behaviors

Depression is a serious psychiatric disorder with unsatisfactory outcomes due to difficulties in delivering therapeutic molecules from the periphery to the brain. Neuroinflammation plays a key role in neurobiology and the treatment of depression. Neutrophils can cross the blood-brain barrier (BBB) and infiltrate key brain regions related to the pathophysiology of depression during neuroinflammation. N-Acetyl Pro-Gly-Pro (PGP) peptides efficiently bind to CXCR2 receptors on the surface of neutrophils. The neuropeptide oxytocin demonstrated antidepressant properties in preclinical and clinical studies, but its inability to penetrate the BBB hampers its therapeutic applications. In this study, we established a novel drug delivery system based on neutrophil infiltration in key brain regions during neuroinflammation. PGP was used to modify oxytocin-loaded liposomes (PGP-OTL) as the target ligand. Systematic administration of PGP-OTL exhibited enhanced antidepressant properties resulting from elevated oxytocin concentrations, especially in the amygdala, a crucial depression-implicated brain region. Enhanced antidepressant effects of PGP-OTL, similar to the ones caused by central oxytocin infusion, were observed in behavioral measurement including forced swim and tail suspension tests. Our study demonstrated that PGP-OTL can "hitchhike" neutrophils and enhance delivery of therapeutics into the brain, thus providing the means for developing novel cell-liposome-based drug delivery strategies for depression therapy.

Chemotherapy-Induced Cognitive Impairment and Hippocampal Neurogenesis: A Review of Physiological Mechanisms and Interventions

A wide range of cognitive deficits, including memory loss associated with hippocampal dysfunction, have been widely reported in cancer survivors who received chemotherapy. Changes in both white matter and gray matter volume have been observed following chemotherapy treatment, with reduced volume in the medial temporal lobe thought to be due in part to reductions in hippocampal neurogenesis. Pre-clinical rodent models confirm that common chemotherapeutic agents used to treat various forms of non-CNS cancers reduce rates of hippocampal neurogenesis and impair performance on hippocampally-mediated learning and memory tasks. We review the pre-clinical rodent literature to identify how various chemotherapeutic drugs affect hippocampal neurogenesis and induce cognitive impairment. We also review factors such as physical exercise and environmental stimulation that may protect against chemotherapy-induced neurogenic suppression and hippocampal neurotoxicity. Finally, we review pharmacological interventions that target the hippocampus and are designed to prevent or reduce the cognitive and neurotoxic side effects of chemotherapy.

Artificial Light at Night Reduces Anxiety-like Behavior in Female Mice with Exacerbated Mammary Tumor Growth

Simple Summary

Artificial light at night, initially assumed to be innocuous, is associated with an increased risk for developing mood disorders, sleep disturbances, and cancer. However, the influence of ALAN on affective behavior in tumor-bearing mice has not been investigated. Here, we demonstrate that ALAN reduces the latency to tumor onset and increases terminal tumor volume. Additionally, tumor-bearing mice housed in dark nights exhibit increased anxiety-like behavior which is prevented via housing in ALAN.

Abstract

Artificial light at night (ALAN) is a pervasive phenomenon. Although initially assumed to be innocuous, recent research has demonstrated its deleterious effects on physiology and behavior. Exposure to ALAN is associated with disruptions to sleep/wake cycles, development of mood disorders, metabolic disorders, and cancer. However, the influence of ALAN on affective behavior in tumor-bearing mice has not been investigated. We hypothesize that exposure to ALAN accelerates mammary tumor growth and predict that ALAN exacerbates negative affective behaviors in tumor-bearing mice. Adult (>8 weeks) female C3H mice received a unilateral orthotropic injection of FM3A mouse mammary carcinoma cells (1.0 × 10⁵ in 100 μL) into the fourth inguinal mammary gland. Nineteen days after tumor inoculation, mice were tested for sucrose preference (anhedonia-like behavior). The following day, mice were subjected to an open field test (anxiety-like behavior), followed by forced swim testing (depressive-like behavior). Regardless of tumor status, mice housed in ALAN increased body mass through the first ten days. Tumor-bearing ALAN-housed mice demonstrated reduced latency to tumor onset (day 5) and increased terminal tumor volume (day 21). Exposure to ALAN reduced sucrose preference independent of tumor status. Additionally, tumor-bearing mice housed in dark nights demonstrated significantly increased anxiety-like behavior that was normalized via housing in ALAN. Together, these data reaffirm the negative effects of ALAN on tumorigenesis and demonstrate the potential anxiolytic effect of ALAN in the presence of mammary tumors.

Targeting the Oxytocinergic System: A Possible Pharmacological Strategy for the Treatment of Inflammation Occurring in Different Chronic Diseases

Unresolved inflammation represents a central feature of different human pathologies including neuropsychiatric, cardiovascular, and metabolic diseases. The epidemiologic relevance of such disorders justifies the increasing interest in further understanding the mechanisms underpinning the inflammatory process occurring in such chronic diseases to provide potential novel pharmacological approaches. The most common and effective therapies for controlling inflammation are glucocorticoids; however, a variety of other molecules have been demonstrated to have an anti-inflammatory potential, including neuropeptides. In recent years, the oxytocinergic system has seen an explosion of scientific studies, demonstrating its potential to contribute to a variety of physiological processes including inflammation. Therefore, the aim of the present review was to understand the role of oxytocin in the modulation of inflammation occurring in different chronic diseases. The criterion we used to select the diseases was based on the emerging literature showing a putative involvement of the oxytocinergic system in inflammatory processes in a variety of pathologies including neurological, gastrointestinal and cardiovascular disorders, diabetes and obesity. The evidence reviewed here supports a beneficial role of oxytocin in the control of both peripheral and central inflammatory response happening in the aforementioned pathologies. Although future studies are necessary to elucidate the mechanistic details underlying such regulation, this review supports the idea that the modulation of the endogenous oxytocinergic system might represent a new potential pharmacological approach for the treatment of inflammation.

Love and fear in the times of sickness

Sickness induced by gastrointestinal malaise or by microbial pathogens is more than a private experience. Sick individuals share their illness within their social environment by communicating their sickness to others. In turn, recipients of the communication respond with appropriate behavioral adaptations. Avoidance of sick individuals and the events associated with their sickness is advantageous for members of the group. However, these responses can conflict with the need for comfort or social support expressed by sick individuals. There is evidence that the relationship between the sick individual and its social environment involves neurobiological mechanisms that are similar to those that mediate social bonding. Despite their commonality the feelings of love and fear/disgust that are associated with the sociality of sickness have thus far been neglected by mainstream affective neuroscience.