Immune-enhancing effects of glucocorticoids in response to day-night cycles and stress

Ecological countermeasures to prevent pathogen spillover and subsequent pandemics

Substantial global attention is focused on how to reduce the risk of future pandemics. Reducing this risk requires investment in prevention, preparedness, and response. Although preparedness and response have received significant focus, prevention, especially the prevention of zoonotic spillover, remains largely absent from global conversations. This oversight is due in part to the lack of a clear definition of prevention and lack of guidance on how to achieve it. To address this gap, we elucidate the mechanisms linking environmental change and zoonotic spillover using spillover of viruses from bats as a case study. We identify ecological interventions that can disrupt these spillover mechanisms and propose policy frameworks for their implementation. Recognizing that pandemics originate in ecological systems, we advocate for integrating ecological approaches alongside biomedical approaches in a comprehensive and balanced pandemic prevention strategy.

Could a Non-Cellular Molecular Interactome in the Blood Circulation Influence Pathogens' Infectivity?

We advance the notion that much like artificial nanoparticles, relatively more complex biological entities with nanometric dimensions such as pathogens (viruses, bacteria, and other microorganisms) may also acquire a biomolecular corona upon entering the blood circulation of an organism. We view this biomolecular corona as a component of a much broader non-cellular blood interactome that can be highly specific to the organism, akin to components of the innate immune response to an invading pathogen. We review published supporting data and generalize these notions from artificial nanoparticles to viruses and bacteria. Characterization of the non-cellular blood interactome of an organism may help explain apparent differences in the susceptibility to pathogens among individuals. The non-cellular blood interactome is a candidate therapeutic target to treat infectious and non-infectious conditions.

BmMD-2A responds to 20-hydroxyecdysone and regulates Bombyx mori silkworm innate immunity in larva-to-pupa metamorphosis

20E-hydroxyecdysone (20E) plays important roles in larval molting and metamorphosis in insects and is also involved in the insect innate immune response. Insect metamorphosis is a highly successful strategy for environmental adaptation and is the most vulnerable stage during which the insect is susceptible to various pathogens. 20E regulates a series of antimicrobial peptides (AMPs) through the immunodeficiency (IMD) pathway activation in Drosophila; nevertheless, whether other immune pathways are involved in 20E-regulated insect immunity is unknown. Our previous studies showed that BmMD-2A is a member of the MD-2-related lipid recognition (ML) family of proteins that are involved in the Bombyx mori innate immunity Toll signaling pathway. In this study, we further demonstrate that BmMD-2A is also positively regulated by 20E, and the BmMD-2A neutralization experiment suggested that 20E activates some downstream immune effect factors, the AMP genes against Escherichia coli and Staphylococcus aureus, through the regulation of BmMD-2A in larval metamorphosis, implying that B. mori may use the Toll-ML signaling pathway to maintain innate immune balance in the larval-pupal metamorphosis stage, which is a different innate immunity pathway regulated by 20E compared to the IMD pathway in Drosophila.

Psychoneurological Symptoms and Biomarkers of Stress and Inflammation in Newly Diagnosed Head and Neck Cancer Patients: A Network Analysis

Psychoneurological symptoms are commonly reported by newly diagnosed head and neck cancer (HNC) patients, yet there is limited research on the associations of these symptoms with biomarkers of stress and inflammation. In this article, pre-treatment data of a multi-center cohort of HNC patients were analyzed using a network analysis to examine connections between symptoms (poor sleep quality, anxiety, depression, fatigue, and oral pain), biomarkers of stress (diurnal cortisol slope), inflammation markers (c-reactive protein [CRP], interleukin [IL]-6, IL-10, and tumor necrosis factor alpha [TNF-α]), and covariates (age and body mass index [BMI]). Three centrality indices were calculated: degree (number of connections), closeness (proximity of a variable to other variables), and betweenness (based on the number of times a variable is located on the shortest path between any pair of other variables). In a sample of 264 patients, poor sleep quality and fatigue had the highest degree index; fatigue and CRP had the highest closeness index; and IL-6 had the highest betweenness index. The model yielded two clusters: a symptoms-cortisol slope-CRP cluster and a IL-6-IL-10-TNF-α-age-BMI cluster. Both clusters were connected most prominently via IL-6. Our findings provide evidence that poor sleep quality, fatigue, CRP, and IL-6 play an important role in the interconnections between psychoneurological symptoms and biomarkers of stress and inflammation in newly diagnosed HNC patients.

Could Endogenous Glucocorticoids Influence SARS-CoV-2 Infectivity?

Endogenous glucocorticoids and their synthetic analogues, such as dexamethasone, stimulate receptor-mediated signal transduction mechanisms on target cells. Some of these mechanisms result in beneficial outcomes whereas others are deleterious in the settings of pathogen infections and immunological disorders. Here, we review recent studies by several groups, including our group, showing that glucocorticoids can directly interact with protein components on SARS-CoV-2, the causative agent of COVID-19. We postulate an antiviral defence mechanism by which endogenous glucocorticoids (e.g., cortisol produced in response to SARS-CoV-2 infection) can bind to multiple sites on SARS-CoV-2 surface protein, Spike, inducing conformational alterations in Spike subunit 1 (S1) that inhibit SARS-CoV-2 interaction with the host SARS-CoV-2 receptor, ACE2. We suggest that glucocorticoids-mediated inhibition of S1 interaction with ACE2 may, consequently, affect SARS-CoV-2 infectivity. Further, glucocorticoids interactions with Spike could protect against a broad spectrum of coronaviruses and their variants that utilize Spike for infection of the host. These notions may be useful for the design of new antivirals for coronavirus diseases.

Psychological intervention to treat distress: An emerging frontier in cancer prevention and therapy

Psychological distress, such as chronic depression and anxiety, is a topical problem. In the context of cancer patients, prevalence rates of psychological distress are four-times higher than in the general population and often confer worse outcomes. In addition to evidence from epidemiological studies confirming the links between psychological distress and cancer progression, a growing body of cellular and molecular studies have also revealed the complex signaling networks which are modulated by psychological distress-derived chronic stress during cancer progression. In this review, aiming to uncover the intertwined networks of chronic stress-driven oncogenesis and progression, we summarize physiological stress response pathways, like the HPA, SNS, and MGB axes, that modulate the release of stress hormones with potential carcinogenic properties. Furthermore, we discuss in detail the mechanisms behind these chronic stimulations contributing to the initiation and progression of cancer through direct regulation of cancer hallmarks-related signaling or indirect promotion of cancer risk factors (including obesity, disordered circadian rhythms, and premature senescence), suggesting a novel research direction into cancer prevention and therapy on the basis of psychological interventions.

Blood transfusion practices affect CD4+ CD25+ FOXP3+ regulatory T cells/T helper-17 cells and the clinical outcome of geriatric patients with hip fracture

Hip fracture (HF) is common among older individuals and associated with high mortality, poor vitality and functional impairment. HF patients suffer whole body immunological changes and that lead to severe consequences, including immobilization, physical impairment and a high risk of complications. The objective of this study was to decipher the pattern of dynamic immunological changes, especially in two major T cell subsets, CD4⁺ CD25⁺ FOXP3⁺ regulatory T (Treg) cells and T helper-17 (Th17) cells, and their balance, during the hospital stay and to observe whether blood transfusion could influence these cells and clinical patietns' prognosis. In this study, ninety-eight consecutive HF patients were initially enrolled, and finally fifty-one patients qualified for the study, and correlation analysis of their clinical parameters was carried out to predict the meaning of their distribution in clinical practice. Our results showed that the frequency of Tregs gradually decreased, while the frequency of Th17 cells slowly increased in HF patients who received blood transfusion. The Treg frequency was inversely correlated with the level of hemoglobin (Hb), and Th17 cell frequency was positively related to fluctuations in Hb levels in HF patients after trauma. HF patients with a better prognosis and survival time showed decreased a Treg frequency and a decreased Treg/Th17 ratio. Transfusion helped reverse the imbalance in the frequencies of Tregs and Th17 cells and the Treg/Th17 ratio and especially contributed to a better outcome in HF patients with moderate-to-severe anemia. In conclusion, a higher frequency of peripheral blood Tregs and a higher Treg/Th17 ratio may be associated with unfavorable outcomes in HF patients, and blood transfusion may benefit moderate-to-severe HF patients rebalance their immune response.