Harmful Stimuli Research Articles

Phase-Directed Assembly of Triboelectric Nanopaper for Self-Powered Noncontact Sensing.

Noncontact sensing technology serves as a pivotal medium for seamless data acquisition and intelligent perception in the era of the Internet of Things (IoT), bringing innovative interactive experiences to wearable human-machine interaction perception networks. However, the pervasive limitations of current noncontact sensing devices posed by harsh environmental conditions hinder the precision and stability of signals. In this study, the triboelectric nanopaper prepared by a phase-directed assembly strategy is presented, which possesses low charge transfer mobility (1618 cm2 V-1 s-1) and exceptional high-temperature stability. Wearable self-powered noncontact sensors constructed from triboelectric nanopaper operate stably under high temperatures (200 °C). Furthermore, a temperature warning system for workers in hazardous environments is demonstrated, capable of nonintrusively identifying harmful thermal stimuli and detecting motion status. This research not only establishes a technological foundation for accurate and stable noncontact sensing under high temperatures but also promotes the sustainable intelligent development of wearable IoT devices under extreme environments.

Mechanosensory bristles mediate avoidance behavior by triggering sustained local motor activity in Drosophila melanogaster

During locomotion, most vertebrates-and invertebrates such as Drosophila melanogaster-are able to quickly adapt to terrain irregularities or avoid physical threats by integrating sensory information along with motor commands. Key to this adaptability are leg mechanosensory structures, which assist in motor coordination by transmitting external cues and proprioceptive information to motor centers in the central nervous system. Nevertheless, how different mechanosensory structures engage these locomotor centers remains poorly understood. Here, we tested the role of mechanosensory structures in movement initiation by optogenetically stimulating specific classes of leg sensory structures. We found that stimulation of leg mechanosensory bristles (MsBs) and the femoral chordotonal organ (ChO) is sufficient to initiate forward movement in immobile animals. While the stimulation of the ChO required brain centers to induce forward movement, unexpectedly, brief stimulation of leg MsBs triggered a fast response and sustained motor activity dependent only on the ventral nerve cord (VNC). Moreover, this leg-MsB-mediated movement lacked inter- and intra-leg coordination but preserved antagonistic muscle activity within joints. Finally, we show that leg-MsB activation mediates strong avoidance behavior away from the stimulus source, which is preserved even in the absence of a central brain. Overall, our data show that mechanosensory stimulation can elicit a fast motor response, independently of central brain commands, to evade potentially harmful stimuli. In addition, it sheds light on how specific sensory circuits modulate motor control, including initiation of movement, allowing a better understanding of how different levels of coordination are controlled by the VNC and central brain locomotor circuits.

Boldine prevents the inflammatory response of cardiac fibroblasts induced by SGK1-NFκB signaling pathway activation

Cardiac fibroblasts (CF) are mesenchymal-type cells responsible for maintaining the homeostasis of the heart's extracellular matrix (ECM). Their dysfunction leads to excessive secretion of ECM proteins, tissue stiffening, impaired nutrient and oxygen exchange, and electrical abnormalities in the heart. Additionally, CF act as sentinel cells in the cardiac tissue microenvironment, responding to various stimuli that may affect heart function. Deleterious stimuli induce an inflammatory response in CF, increasing the secretion of cytokines such as IL-1β and TNF-α and the expression of cell adhesion molecules like ICAM1 and VCAM1, initially promoting damage resolution by recruiting immune cells. However, constant harmful stimuli lead to a chronic inflammatory process and heart dysfunction. Therefore, it is necessary to study the mechanisms that govern CF inflammation. NFκB is a key regulator of the cardiac inflammatory process, making the search for mechanisms of NFκB regulation and CF inflammatory response crucial for developing new treatment options for cardiovascular diseases. SGK1, a serine-threonine protein kinase, is one of the regulators of NFκB and is involved in the fibrotic effects of angiotensin II and aldosterone, as well as in CF differentiation. However, its role in the CF inflammatory response is unknown. On the other hand, many bioactive natural products have demonstrated anti-inflammatory effects, but their role in CF inflammation is unknown. One such molecule is boldine, an alkaloid obtained from Boldo (Peumus boldus), a Chilean endemic tree with proven cytoprotective effects. However, its involvement in the regulation of SGK1 and CF inflammation is unknown. In this study, we evaluated the role of SGK1 and boldine in the inflammatory response in CF isolated from neonatal Sprague-Dawley rats. The involvement of SGK1 was analyzed using GSK650394, a specific SGK1 inhibitor. Our results demonstrate that SGK1 is crucial for LPS- and IFN-γ-induced inflammatory responses in CF (cytokine expression, cell adhesion molecule expression, and leukocyte adhesion). Furthermore, a conditioned medium (intracellular content of CF subject to freeze/thaw cycles) was used to simulate a sterile inflammation condition. The conditioned medium induced a potent inflammatory response in CF, which was completely prevented by the SGK1 inhibitor. Finally, our results indicate that boldine inhibits both SGK1 activation and the CF inflammatory response induced by LPS, IFN-γ, and CF-conditioned medium. Taken together, our results position SGK1 as an important regulator of the CF inflammatory response and boldine as a promising anti-inflammatory drug in the context of cardiovascular diseases.

TRPV1 nociceptors are required to optimize antigen-specific primary antibody responses to novel antigens

BackgroundKey to the advancement of the field of bioelectronic medicine is the identification of novel pathways of neural regulation of immune function. Sensory neurons (termed nociceptors) recognize harmful stimuli and initiate a protective response by eliciting pain and defensive behavior. Nociceptors also interact with immune cells to regulate host defense and inflammatory responses. However, it is still unclear whether nociceptors participate in regulating primary IgG antibody responses to novel antigens.MethodsTo understand the role of transient receptor potential vanilloid 1 (TRPV1)-expressing neurons in IgG responses, we generated TRPV1-Cre/Rosa-ChannelRhodopsin2 mice for precise optogenetic activation of TRPV1 + neurons and TRPV1-Cre/Lox-diphtheria toxin A mice for targeted ablation of TRPV1-expressing neurons. Antigen-specific antibody responses were longitudinally monitored for 28 days.ResultsHere we show that TRPV1 expressing neurons are required to develop an antigen-specific immune response. We demonstrate that selective optogenetic stimulation of TRPV1+ nociceptors during immunization significantly enhances primary IgG antibody responses to novel antigens. Further, mice rendered deficient in TRPV1- expressing nociceptors fail to develop primary IgG antibody responses to keyhole limpet hemocyanin or haptenated antigen.ConclusionThis functional and genetic evidence indicates a critical role for nociceptor TRPV1 in antigen-specific primary antibody responses to novel antigens. These results also support consideration of potential therapeutic manipulation of nociceptor pathways using bioelectronic devices to enhance immune responses to foreign antigens.

Evaluation of the Anti-inflammatory Effects of Methanol Extract of Rauwofia vomitera Leaves (MERVL) Using In-vivo Based Assays

Background of the Study: The response of the body to harmful stimuli, such as tissue damage or a pathogenic infection is known as inflammation. Rauwofia vomitera is a medicinal plant that is native to large areas of tropical Africa and it belongs to the family of Apocynaceae. It is a medicinal herb used in traditional Nigerian medicine to treat a variety of diseases, including inflammatory disorders. Aim of the Study:The present study investigated the anti-inflammatory effects of methanol extract of Rauwofia vomitera leaves (MERVL) using in-vivo based assays. Methodology: The anti-inflammatory effect of (MERVL) was ascertained using the Egg albumin -induced inflammation using in vivo assay. A total of thirty (30) adult male albino rats (130-170g) were divided into five (5) groups of six (6) rats each for the in-vivo anti-inflammatory assay. Group 1 normal; Group 2 was given 10 mg/kg body weight of Indomethacin and Groups 3, 4 and 5 were given 100, 200 and 400 mg/kg body weight of MERVL) respectively. Acute toxicity was carried out using standard method. Place and Duration of the Study: Department of Pharmacology Lab, Enugu State of University of Science and Technology Agbani Nigeria, between March 2021 and August 2021. Results: The percentage yield of the extract was 10.8%. The result of the quantitative and qualitative phytochemical screening of methanol extract of R. vomitoria leaves showed that Phenol (1590 ± 55.66) Flavonoid (1168 ± 11.43) and Tannin (1466 ± 40.73) were present in high concentration whereas, Alkaloid (549 ± 4.21) Glycoside (315 ± 61.38) and Terpenoid (162 ± 1.38) were present in moderate concentration. Saponin (1.16 ± 0.23) and Steroid (0.84 ± 0.03) were present in low concentrations. Acute toxicity tests showed no toxicity and mortality at doses up to 5000 mgkg-1. A significant (P < 0.05) reduction in the mean paw oedema was observed for all the treatment groups from 1 hour to 12 hours when compared to the normal group. The result shown that groups treated with 100, 200 and 400 mg/kg b.w of extract inhibit the inflammation in a non-dose dependent manner with percentage mobilization of 5.7%, 14.1% and 6.2% respectively. Conclusion: The study's results demonstrate that MERVL exhibits remarkable anti-inflammatory and anti-oxidant activities and the extract yielded a better reduction in edema and increases mobilization in leukocyte in response to agar suspension. It also demonstrates that MERVL has a modulatory effect on the vascular changes that accompany inflammation. The plant's anti-inflammatory properties could potentially result from the interaction of different photochemical substances present. The findings suggest that, if used, the plant may serve as a source of anti-inflammatory agents.

TRPV1+ Sensory nerves modulate antigen specific immune responses

Abstract Sensory neurons recognize harmful or noxious stimuli and initiate a protective response by eliciting pain and defensive behavior. Nociceptors also interact with immune cells to regulate immune responses and play a key role in modulating antibody class switching to IgE. However, it is still unknown whether nociceptors participate in regulating primary IgG antibody responses to novel antigens. Here, we show that TRPV1 expressing nociceptors are required to develop an antigen specific immune response and that direct activation of TRPV1+ signals by selective optogenetic stimulation enhances primary IgG antibody responses to novel antigen. Specific ablation of TRPV1+ neurons, which include nociceptors, significantly blunts NP-specific IgG antibody responses in TRPV1-DTA mice compared to controls (anti-NP2 IgG AU, Day 28 control, 18,401 ± 3393 n=18 versus TRPV1-DTA, 9,028 ± 1,498, n=18, p< 0.001). Selective optogenetic stimulation of TRPV1+ nociceptors on the dorsum of the paw with blue light (473nm, 3Hz, 20%DC, 15min) immediately prior to a local immunization in TRPV1-ChR2 mice significantly increases KLH-specific IgG antibody responses compared to sham stimulation controls (anti-KLH IgG ng/mL Day 28, TRPV1-ChR2: 2,581 ± 476, n= 6 versus Control, 1,224 ± 332, n=8; * p<0.05). Together these studies with genetic and selective functional evidence indicates that nociceptors are required during immunization to produce primary antigen-specific IgG antibody responses to novel antigens.

Behavioral and pharmacological characterization of planarian nociception.

Pain mostly arises because specialized cells called nociceptors detect harmful or potentially harmful stimuli. In lower animals with less convoluted nervous system, these responses are believed to be purely nociceptive. Amongst invertebrate animal models, planarians are becoming popular in a wide range of pharmacological and behavioral studies beyond the field of regeneration. Recent publications led the way on pain studies by focusing on nociceptive behaviors such as the 'scrunching' gait displayed under various noxious stimuli, as opposed to the 'gliding' gait planarians usually adopt in normal conditions. In this study, we adapted commonly used nociceptive tests to further explore nociception in planarians of the species Girardia dorotocephala. By using behavioral analysis in open fields and place preferences, we managed to set up chemical, thermal and mechanical nociceptive tests. We also adapted RNA interference protocols and explored the effects of knocking down TRPA1 ion channels, one of the main effectors of chemically and thermally-induced nociceptive responses in vertebrates. Consequently, we demonstrated the reliability of the scrunching gait in this planarian species, which they displayed in a dose-dependent manner when exposed to the irritant AITC. We also showed that suppressing the expression of TRPA1 ion channels completely suppressed the scrunching gait, demonstrating the involvement of TRPA1 nociceptors in this nociceptive reaction. Besides, we also explored the effects of two common analgesics that both displayed strong antinociceptive properties. First, morphine reduced the chemically-induced nociceptive scrunching gaits by more than 20% and shifted the of the dose-response curve by approximately 10 μM. Secondly, the NSAID meloxicam drastically reduced chemically-induced scrunching by up to 60% and reduced heat avoidance in place preference tests. Thus, we managed to characterize both behavioral and pharmacological aspects of G. dorotocephala's nociception, further developing the use of planarians as a replacement model in pain studies and more globally the study of invertebrate nociception.

Multimodal monitoring using the Analgesia Nociception Index (ANI) during catheter ablation of the heart in patients with sinus rhythm and short-term induced atrial arrhythmia: prospective observational study

INTRODUCTION: Сatheter ablation (CA) is a painful procedure requiring an assessment of the balance between nociception associated with surgical trauma and anesthesia induced antinociception. OBJECTIVE: To evaluate the effectiveness of the monitoring system “ANI Monitor” for anesthesia and intensive care in patients with sinus rhythm and short-term induced (< 1 min) atrial arrhythmia (STIAA). MATERIALS AND METHODS: The study group of our trial consisted of 94 patients with CA and ANI Monitor. The control group consisted of 94 patients, selected using the “copy-pair” method, with standard (hemodynamic) monitoring. A Numerical Rating Scale (NRS) was used for assessment the intensity of pain. At the stage of femoral vein catheterization in all patients regional anesthesia was performed, at the CA stage, procedural sedation and/or analgesia (PSA) was titrated with the administration of propofol and fentanyl (under the control with ANI Monitor). Statistical data processing was carried out using Statistica 10.0 and SPSS programs. RESULTS: At the stage of CA under PSA, negative correlation was found between NRS and ANIm in patients with sinus rhythm and STIAA (r = −0.37). At the threshold of 56.0 the sensitivity and specificity of ANIm in detecting NRS ˃ 3 were 60 and 100 %, respectively, corresponding to ROC curve AUC of 0.81. Significant changes in hemodynamic reactivity were not registered. It was revealed the reduction of fentanyl administration in patients of the study group (0.04 ± 0.02 and 0.05 ± 0.03 µg/kg/min, respectively, p < 0.001) under the control of ANI Monitor. CONCLUSIONS: ANI Monitor during CA in patients with sinus rhythm and STIAA was more effective in detecting harmful nociceptive stimuli compared to standard (hemodynamic) monitoring. The use of ANI Monitor to control the fentanyl administration could create conditions for opioid-sparing anesthesia.

Inflammation in Health and Disease: Novel Therapeutic Approaches

Inflammation, which is regarded as an innate immune mechanism, is a part of the intricate biological reactions of a tissue to injury that shield the organ by eliminating harmful stimuli and starting the healing process. The majority of non-steroidal anti- inflammatory medications on the market work well for inflammatory diseases. Several compounds that disrupt the inflammatory response have also been identified in Indian Medicinal Plants (IMP). The multitude of side effects associated with the anti-inflammatory medications now on the market has a negative impact on human well-being. Advent of novel anti-inflammatory therapies such as herbal preparations, recent developments in the use of bioactive ingredients from herbal remedies to treat osteoarthritis and in the application of synthetic COX-2 inhibitors, chitosan as a therapy for oral mucosal irritation, improvement in the medication used to treat acute pancreatitis, extracellular vesicles from mesenchymal cells for the therapy of inflammation, oral colonic drug delivery methods for treating inflammatory bowel disease and combined targeting therapy for inflammatory bowel management will not only effectively manage the inflammation and its associated disorders but also helps to significantly improve the quality of life. Hence the current review reveals the recent advances in the field of inflammation and anti-inflammatory activity in detail.

Tissue adaptation of CD4 T lymphocytes in homeostasis and cancer.

The immune system is traditionally classified as a defense system that can discriminate between self and non-self or dangerous and non-dangerous situations, unleashing a tolerogenic reaction or immune response. These activities are mainly coordinated by the interaction between innate and adaptive cells that act together to eliminate harmful stimuli and keep tissue healthy. However, healthy tissue is not always the end point of an immune response. Much evidence has been accumulated over the years, showing that the immune system has complex, diversified, and integrated functions that converge to maintaining tissue homeostasis, even in the absence of aggression, interacting with the tissue cells and allowing the functional maintenance of that tissue. One of the main cells known for their function in helping the immune response through the production of cytokines is CD4+ T lymphocytes. The cytokines produced by the different subtypes act not only on immune cells but also on tissue cells. Considering that tissues have specific mediators in their architecture, it is plausible that the presence and frequency of CD4+ T lymphocytes of specific subtypes (Th1, Th2, Th17, and others) maintain tissue homeostasis. In situations where homeostasis is disrupted, such as infections, allergies, inflammatory processes, and cancer, local CD4+ T lymphocytes respond to this disruption and, as in the healthy tissue, towards the equilibrium of tissue dynamics. CD4+ T lymphocytes can be manipulated by tumor cells to promote tumor development and metastasis, making them a prognostic factor in various types of cancer. Therefore, understanding the function of tissue-specific CD4+ T lymphocytes is essential in developing new strategies for treating tissue-specific diseases, as occurs in cancer. In this context, this article reviews the evidence for this hypothesis regarding the phenotypes and functions of CD4+ T lymphocytes and compares their contribution to maintaining tissue homeostasis in different organs in a steady state and during tumor progression.

Neutrophil extracellular traps as a unique target in the treatment of inflammatory pain

Pain is a widespread motivation for seeking healthcare and stands as a substantial global public health concern. Despite comprehensive investigations into the mechanisms of pain sensitization induced by inflammation, efficacious treatments options remain scarce. Neutrophil extracellular traps (NETs) have been associated with the progression and tissue damage of diverse inflammatory diseases. This study aims to explore the impact of NETs on the progression of inflammatory pain and explore potential therapeutic approaches. Initially, we observed neutrophil infiltration and the formation of NETs in the left hind paw of mice with inflammatory pain induced by complete Freund's adjuvant (CFA). Furthermore, we employed the peptidyl arginine deiminase 4 (PAD4) inhibitor Cl-amidine (diluted at 50 mg/kg in saline, administered via tail vein injection once daily for three days) to impede NETs formation and administered DNase1 (diluted at 10 mg/kg in saline, once daily for three days) to break down NETs. We investigated the pathological importance of peripheral NETs formation in inflammatory pain and its influence on the activation of spinal dorsal horn microglia. The findings indicate that neutrophils infiltrating locally generate NETs, leading to an increased release of inflammatory mediators that worsen peripheral inflammatory reactions. Consequently, this results in the transmission of more harmful peripheral stimuli to the spinal cord, triggering microglial activation and NF-κB phosphorylation, thereby escalating neuroinflammation and fostering pain sensitization. Suppression of peripheral NETs can mitigate peripheral inflammation in mice with inflammatory pain, reverse mechanical and thermal hypersensitivity by suppressing microglial activation in the spinal cord, ultimately diminishing inflammatory pain. In conclusion, these discoveries propose that obstructing or intervening with NETs introduces a novel therapeutic avenue for addressing inflammatory pain.

Blood Biomarker and Physical Activity Correlations in Persons with Parkinson’s Disease

Parkinson’s disease (PD) is a debilitating disease that reduces an individual’s quality of life (QOL). PD has a complex pathophysiology, but inflammation is a major contributor. Inflammation is a biological process that removes harmful stimuli and initiates the healing cascade. Researchers commonly use inflammatory markers, such as tumor necrosis factor-alpha (TNFα),interferon-gamma (IFNγ), and interleukin 1-beta (IL1β), to study PD pathologies. While PD is irreversible, physical activity is a non-pharmacological treatment exhibiting beneficial outcomes related to PD and inflammation. To determine if exercise frequency affects the quality of life (QOL) and the magnitude of change in inflammatorybiomarkers associated with PD. Researchers recruited 10 individuals diagnosed with PD to participate in a cross-sectional study. Participants completed four questionnaires to determine their current physical activity (PA) level and QOL. Blood samples were analyzed to determine differences in serum TNFα, IFNγ, and IL1β concentrations between different PA levels of persons with PD. With an alpha level of 0.05, this project only yielded two significant results: an unexpected positive relationship between IL1β and PA level and an expected negative relationship between IL1β and QOL. Although they were not significant, several results trended in the expected directions. Discussion: Observed trends indicated that increasing physical activity decreases inflammatory blood biomarker levels and increases QOL while increasing sedentary behavior increases inflammatory blood biomarker levels and decreases QOL.

Expansion and diversity of caspases in Mytilus coruscus contribute to larval metamorphosis and environmental adaptation

BackgroundApoptosis is involved (directly and indirectly) in several physiological processes including tissue remodeling during the development, the turnover of immune cells, and a defense against harmful stimuli. The disordered apoptotic process participates in the pathogenesis of various diseases, such as neoplasms, and chronic inflammatory or systemic autoimmune diseases, which are associated with its inadequate regulation. Caspases are vital components of the apoptotic pathway that are involved in developmental and immune processes. However, genome-wide identification and functional analysis of caspase have not been conducted in Mytilus coruscus, which is an economically important bivalve.ResultsHere, 47 caspase genes were identified from the genomes of M. coruscus, and the expansion of caspase-2/9 and caspase-3/6/7 genes were observed. Tandem duplication acts as an essential driver of gene expansion. The expanded caspase genes were highly diverse in terms of sequence, domain structure, and spatiotemporal expression profiles, suggesting their functional differentiation. The high expression of the expanded caspase genes at the pediveliger larvae stage and the result of apoptosis location in the velum suggest that the apoptosis mediated by them plays a critical role in the metamorphosis of M. coruscus larvae. In gill, caspase genes respond differently to the challenge of different strains, and most caspase-2/9 and caspase-3/6/7 genes were induced by copper stress, whereas caspase-8/10 genes were suppressed. Additionally, most caspase genes were upregulated in the mantle under ocean acidification which could weaken the biomineralization capacity of the mantle tissue.ConclusionsThese results provide a comprehensive overview of the evolution and function of the caspase family and enhanced the understanding of the biological function of caspases in M. coruscus larval development and response to biotic and abiotic challenges.

Penehyclidine hydrochloride alleviates LPS-induced inflammatory responses and oxidative stress via ROS/Nrf2/HO-1 activation in RAW264.7 cells.

Inflammation is a biological response of the immune system to harmful stimuli. Penehyclidine hydrochloride (PCH) can alleviate inflammation and oxidative stress by activating reactive oxygen species (ROS), nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase 1 (HO-1) in animal models, but there is a lack of cellular evidence. This study investigated the effects of PHC on lipopolysaccharide (LPS)-induced inflammation response and oxidative stress in RAW264.7 cells. RAW264.7 cells were treated with 1 μg/mL or 5 μg/mL of PHC, with interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), IL-1β, and prostaglandin E2 (PGE2) levels measured with enzyme-linked immunosorbent assay (ELISA) and nitric oxide (NO) measured using the Griess test. Reactive oxygen species were examined with flow cytometry and immunofluorescence, and b-related factor 2 (BRF-2) and NAD(P)H-quinone oxidoreductase 1 (NQO1) using western blot. Penehyclidine hydrochloride partly, but substantially, reversed LPS-related NO and PGE2 production by RAW264.7 cells in a dose-dependent manner and suppressed LPS-induced expression of IL-6, TNF-α and IL-1β messenger ribonucleic acid (mRNA), secretion of IL-6, TNF-α and IL-1β, and ROS production. Lipopolysaccharide stimulation did not affect Nrf2, heme oxygenase 1 (HO-1) or NQO1 protein expression in RWA264.7 cells not treated with PHC. However, PHC treatment significantly elevated Nrf2, HO-1 and NQO1 protein in LPS-treated RWA264.7 cells, an effect that was dose-dependent. The ROS scavenging using N-acetyl-L-cysteine abolished the PHC-induced upregulation of Nrf2 and HO-1. Penehyclidine hydrochloride may alleviate LPS-induced inflammation and oxidative stress by activating Nrf2 signaling in RAW264.7 macrophages. These findings suggest that PHC could alleviate inflammation by targeting activated macrophages.

Extracellular vesicles secreted from mesenchymal stem cells ameliorate renal ischemia reperfusion injury by delivering miR-100-5p targeting FKBP5/AKT axis

The incidence of acute kidney injury (AKI) due to ischemia–reperfusion (IR) injury is increasing. There is no effective treatment for AKI, and because of this clinical challenge, AKI often progresses to chronic kidney disease, which is closely associated with poor patient outcomes and high mortality rates. Small extracellular vesicles from human umbilical cord mesenchymal stem cells (hUCMSC-sEVs) play increasingly vital roles in protecting tissue function from the effects of various harmful stimuli owing to their specific biological features. In this study, we found that miR-100-5p was enriched in hUCMSC-sEVs, and miR-100-5p targeted FKBP5 and inhibited HK-2 cell apoptosis by activating the AKT pathway. HK-2 cells that were exposed to IR injury were cocultured with hUCMSC-sEVs, leading to an increase in miR-100-5p levels, a decrease in FKBP5 levels, and an increase in AKT phosphorylation at Ser 473 (AKT-473 phosphorylation). Notably, these effects were significantly reversed by transfecting hUCMSCs with an miR-100-5p inhibitor. Moreover, miR-100-5p targeted FKBP5, as confirmed by a dual luciferase reporter assay. In vivo, intravenous infusion of hUCMSC-sEVs into mice suffering from IR injury resulted in significant apoptosis inhibition, functional maintenance and renal histological protection, which in turn decreased FKBP5 expression levels. Overall, this study revealed an effect of hUCMSC-sEVs on inhibiting apoptosis; hUCMSC-sEVs reduced renal IR injury by delivering miR-100-5p to HK-2 cells, targeting FKBP5 and thereby promoting AKT-473 phosphorylation to activate the AKT pathway. This study provides novel insights into the role of hUCMSC-sEVs in the treatment of AKI.

The role of dermal fibroblasts in autoimmune skin diseases.

Fibroblasts are an important subset of mesenchymal cells in maintaining skin homeostasis and resisting harmful stimuli. Meanwhile, fibroblasts modulate immune cell function by secreting cytokines, thereby implicating their involvement in various dermatological conditions such as psoriasis, vitiligo, and atopic dermatitis. Recently, variations in the subtypes of fibroblasts and their expression profiles have been identified in these prevalent autoimmune skin diseases, implying that fibroblasts may exhibit distinct functionalities across different diseases. In this review, from the perspective of their fundamental functions and remarkable heterogeneity, we have comprehensively collected evidence on the role of fibroblasts and their distinct subpopulations in psoriasis, vitiligo, atopic dermatitis, and scleroderma. Importantly, these findings hold promise for guiding future research directions and identifying novel therapeutic targets for treating these diseases.

Insights into targeting cellular senescence with senolytic therapy: The journey from preclinical trials to clinical practice

Interconnected, fundamental aging processes are central to many illnesses and diseases. Cellular senescence is a mechanism that halts the cell cycle in response to harmful stimuli. Senescent cells (SnCs) can emerge at any point in life, and their persistence, along with the numerous proteins they secrete, can negatively affect tissue function. Interventions aimed at combating persistent SnCs, which can destroy tissues, have been used in preclinical models to delay, halt, or even reverse various diseases. Consequently, the development of small-molecule senolytic medicines designed to specifically eliminate SnCs has opened potential avenues for the prevention or treatment of multiple diseases and age-related issues in humans. In this review, we explore the most promising approaches for translating small-molecule senolytics and other interventions targeting senescence in clinical practice. This discussion highlights the rationale for considering SnCs as therapeutic targets for diseases affecting individuals of all ages.

Hematopoiesis Revolves Around the Primordial Evolutional Rhythm of Purinergic Signaling and Innate Immunity – A Journey to the Developmental Roots

A cell's most significant existential task is to survive by ensuring proper metabolism, avoiding harmful stimuli, and adapting to changing environments. It explains why early evolutionary primordial signals and pathways remained active and regulate cell and tissue integrity. This requires energy supply and a balanced redox state. To meet these requirements, the universal intracellular energy transporter purine nucleotide-adenosine triphosphate (ATP) became an important signaling molecule and precursor of purinergic signaling after being released into extracellular space. Similarly, ancient proteins involved in intracellular metabolism gave rise to the third protein component (C3) of the complement cascade (ComC), a soluble arm of innate immunity. These pathways induce cytosol reactive oxygen (ROS) and reactive nitrogen species (RNS) that regulate the redox state of the cells. While low levels of ROS and RNS promote cell growth and differentiation, supra-physiological concentrations can lead to cell damage by pyroptosis. This balance explains the impact of purinergic signaling and innate immunity on cell metabolism, organogenesis, and tissue development. Subsequently, along with evolution, new regulatory cues emerge in the form of growth factors, cytokines, chemokines, and bioactive lipids. However, their expression is still modulated by both primordial signaling pathways. This review will focus on the data that purinergic signaling and innate immunity carry on their ancient developmental task in hematopoiesis and specification of hematopoietic stem/progenitor cells (HSPCs). Moreover, recent evidence shows both these regulatory pathways operate in a paracrine manner and inside HSPCs at the autocrine level.Graphical

A12 ROLE OF INTESTINAL EPITHELIAL HNF4A IN PROTECTING AGAINST ACUTE INFLAMMATORY STIMULI

Abstract Background Inflammatory bowel disease is a group of chronic resulting from complex interactions between host susceptibility genes, the host microbiome, the immune system, and environmental triggers. The gastrointestinal epithelium acts as a barrier against harmful stimuli, and defects in its integrity are a precursor for the development of IBD. Our laboratory has shown that the conditional deletion of Hnf4a in the mouse intestinal epithelium leads to chronic intestinal inflammation. However, the functional role of HNF4A on epithelial barrier integrity is still controversial. Aims To evaluate the impact of Hnf4a deletion on barrier integrity during acute inflammation. Methods We used a tamoxifen-inducible CreER-loxP system to delete Hnf4a in the adult intestinal epithelium (Hnf4aΔIEC-ind). Intestinal permeability was assessed in Hnf4aΔIEC-ind and control mice in the collected serum after oral gavage of FITC-dextran. Mice were infected with an invasion-attenuated strain of Salmonella Typhimurium (SB103). S. Typhimurium loads were scored in the feces, liver, and spleen tissue. Histological analysis was carried out by various staining. Also, we used a model of T-cell-induced enteropathy triggered by a T-cell activating monoclonal anti-CD3ε Ab (145-2C11). Mice were assessed for clinical signs of enteropathy and sacrificed 1-, 3-, and 5 days post-injection. Gene expression of selected targets was studied by RT-qPCR. Results FITC-dextran assay showed a significant increase of the intestinal permeability in uninfected mutant mice compared to controls. In contrast, an oral infection with an invasion-deficient S. Typhimurium strain did not differentially impact in tissue bacterial loads or epithelial damage between groups. Likewise, the loss of epithelial HNF4A led to increased Muc2 transcripts expression in the ileum of infected mutant mice but not in the colon. Histological examinations at four days post-infection showed an elevated number and size of goblet cells in the ileal crypts of mutant mice. Bacterial localization using the general bacterial probe EUB388-cy3 (red) staining showed that infected mutant mice tended to enhance barrier mucus layer thickness compared to the controls. On the contrary, acute T cell activation with anti-CD3 mAb induced a significant increase of mRNA expression of Cxcl1 in the small intestine of mutant mice. H&E staining showed elongated ileal crypts in mutant mice compared to controls after anti-CD3 injection. Conclusions Altogether, these results support that HNF4A could play a crucial adaptive role in modulating the small intestine epithelial barrier function and controlling the immune system during acute inflammatory stress. Funding Agencies CCC, CIHR

Realization of nociceptive receptors based on Mott memristors

Nociceptive receptors are primarily responsible for detecting and responding to potentially harmful stimuli, including painful sensations and tissue damage. In this letter, we designed Pt/Ag/NbO x /W memristors with threshold switching (TS) characteristics and low working voltage attributed to the diffusion of Ag ions within the device. Furthermore, this device successfully emulates the functions of a leaky integrate-and-fire neuron and nervous pain perception functions, respectively. The artificial neurons exhibit multiple neural functions, including leaky integration, threshold-driven firing, self-relaxation characteristics, and allodynia, hyperalgesia of the nociceptors. The proposed TS memristor may show great potential in the field of neuromorphic computing and creating intelligent systems that can replicate the complexity of the human brain.