Cellular stress response and innate immune signaling: integrating pathways in host defense and inflammation

Tauroursodeoxycholic acid ameliorates renal injury induced by COL4A3 mutation

COL4A3/A4/A5 mutations have been identified as critical causes of Alport syndrome and other genetic chronic kidney diseases. However, the underlying pathogenesis remains unclear, and specific treatments are lacking. Here, we constructed a transgenic Alport syndrome mouse model by generating a mutation (Col4a3 p.G799R) identified previously from one large Alport syndrome family into mice. We observed that the mutation caused a pathological decrease in intracellular and secreted collagen IV α3α4α5 heterotrimers. The mutant collagen IV α3 chains abnormally accumulated in the endoplasmic reticulum and exhibited defective secretion, leading to persistent endoplasmic reticulum stress in vivo and in vitro. RNA-seq analysis revealed that the MyD88/p38 MAPK pathway plays key roles in mediating subsequent inflammation and apoptosis signaling activation. Treatment with tauroursodeoxycholic acid, a chemical chaperone drug that functions as an endoplasmic reticulum stress inhibitor, effectively suppressed endoplasmic reticulum stress, promoted secretion of the α3 chains, and inhibited the activation of the MyD88/p38 MAPK pathway. Tauroursodeoxycholic acid treatment significantly improved kidney function in vivo. These results partly clarified the pathogenesis of kidney injuries associated with Alport syndrome, especially in glomeruli, and suggested that tauroursodeoxycholic acid might be useful for the early clinical treatment of Alport syndrome.

Evaluation of Physicochemical Properties and Prebiotics Function of a Bioactive Pleurotus eryngii Aqueous Extract Powder Obtained by Spray Drying

A bioactive Pleurotus eryngii aqueous extract powder (SPAE) was obtained by spray drying and its performance in terms of physicochemical properties, in vitro digestion, inflammatory factors, and modulation of the intestinal microbiota was explored. The results indicated that the SPAE exhibited a more uniform particle size distribution than P. eryngii polysaccharide (PEP). Meanwhile, a typical absorption peak observed at 843 cm-1 in the SPAE FTIR spectra indicated the existence of α-glycosidic bonds. SPAE exhibited higher antioxidant abilities and superior resistance to digestion in vitro. In addition, SPAE supplementation to mice significantly reduced the release of factors that promote inflammation, enhanced the secretion of anti-inflammatory factors, and sustained maximum production of short-chain fatty acids (SCFAs). Additionally, it significantly enhanced the relative abundance of SCFAs-producing Akkermansia and reduced the abundance of Ruminococcus and Clostridiides in intestines of mice. These results show the potential of SPAE as a novel material with prebiotic effects for the food and pharmaceutical industries.

Non-canonical activation of IRE1α during Candida albicans infection enhances macrophage fungicidal activity

While the canonical function of IRE1α is to detect misfolded proteins and activate the unfolded protein response (UPR) to maintain cellular homeostasis, microbial pathogens can also activate IRE1α, which modulates innate immunity and infection outcomes. However, how infection activates IRE1α and its associated inflammatory functions have not been fully elucidated. Recognition of microbe-associated molecular patterns can activate IRE1α, but it is unclear whether this depends on protein misfolding. Here, we report that a common and deadly fungal pathogen, Candida albicans, activates macrophage IRE1α through C-type lectin receptor signaling, reinforcing a role for IRE1α as a central regulator of host responses to infection by a broad range of pathogens. This activation did not depend on protein misfolding in response to C. albicans infection. Moreover, lipopolysaccharide treatment was also able to activate IRE1α prior to protein misfolding, suggesting that pathogen-mediated activation of IRE1α occurs through non-canonical mechanisms. During C. albicans infection, we observed that IRE1α activity promotes phagolysosomal fusion that supports the fungicidal activity of macrophages. Consequently, macrophages lacking IRE1α activity displayed inefficient phagosome maturation, enabling C. albicans to lyse the phagosome, evade fungal killing, and drive aberrant inflammatory cytokine production. Mechanistically, we show that IRE1α activity supports phagosomal calcium flux after phagocytosis of C. albicans, which is crucial for phagosome maturation. Importantly, deletion of IRE1α activity decreased the fungicidal activity of phagocytes in vivo during systemic C. albicans infection. Together, these data provide mechanistic insight for the non-canonical activation of IRE1α during infection, and reveal central roles for IRE1α in macrophage antifungal responses.

Intermittent mild cold acclimation ameliorates intestinal inflammation and immune dysfunction in acute cold-stressed broilers by regulating the TLR4/MyD88/NF-κB pathway

To investigate the potential protective effect of prior cold stimulation on broiler intestine induced by acute cold stress (ACS). A total of 384 one-day-old broilers were divided into control (CON), ACS, cold stimulation Ⅰ (CS3+ACS), and cold stimulation Ⅱ (CS9+ACS) groups. Broilers in CON and ACS groups were reared normally, and birds in CS3+ACS and CS9+ACS groups were reared at 3℃ and 9℃ below CON group for 5 h, respectively, on alternate days from d 15 to 35. Broilers in ACS, CS3+ACS, and CS9+ACS groups were subjected to 10℃ for 24 h on d 43. Eventually, small intestine tissues were collected for histopathological observation and indexes detection. The results showed that intestinal tissues in all ACS-broilers exhibited inflammatory cell infiltrates, microvilli disruption, reduced villus length in jejunum and increased crypt depth in jejunum and ileum. Whereas these phenomena were relatively light in CS3+ACS group. Compared to CON group, mRNA expression of the TLR4/MyD88/NF-κB pathway-related genes (TLR4, MyD88, NF-κBp65, COX-2, iNOS, PTGEs, TNF-α), Th1/Th17-derived cytokines (IL-1β, IL-2, IL-8, IL-12, IFN-γ, IL-17), and HSPs (HSP40, HSP60, HSP70, HSP90) was upregulated (P < 0.05), and that of Th2-deviated cytokines (IL-4, IL-6, IL-10, IL-13) and IκBα was downregulated (P < 0.05) in small intestine in almost all ACS-broilers. Compared to ACS group, mRNA expression of most of the TLR4/MyD88/NF-κB pathway-related genes, Th1/Th17-derived cytokines, and HSPs was downregulated and that of Th2-derived cytokines was upregulated in CS3+ACS group (P < 0.05). Protein expression levels of TLR4, MyD88, p-p65/p65, p-IκBα/IκBα, IKK, TNF-α, IL-1β, IL-10, and HSPs were similar to their mRNA expression. The concentration of sIgA and activities of CAT, SOD, and GSH-px were decreased and MDA and H2O2 were increased in ACS and CS9+ACS groups compared to CON group (P < 0.05). Therefore, cold stress caused oxidative stress and inflammation, leading to gut immune dysfunction; while mild cold stimulation at 3℃ below normal rearing temperature alleviated cold stress-induced intestinal injure and dysfunction by modulating the TLR4/MyD88/NF-κB pathway in broilers.

Pump-Less, Recirculating Organ-on-Chip (rOoC) Platform to Model the Metabolic Crosstalk between Islets and Liver

Type 2 diabetes mellitus (T2DM), obesity, and metabolic dysfunction-associated steatotic liver disease (MASLD) are epidemiologically correlated disorders with a worldwide growing prevalence. While the mechanisms leading to the onset and development of these conditions are not fully understood, predictive tissue representations for studying the coordinated interactions between central organs that regulate energy metabolism, particularly the liver and pancreatic islets, are needed. Here, a dual pump-less recirculating organ-on-chip platform that combines human pluripotent stem cell (sc)-derived sc-liver and sc-islet organoids is presented. The platform reproduces key aspects of the metabolic cross-talk between both organs, including glucose levels and selected hormones, and supports the viability and functionality of both sc-islet and sc-liver organoids while preserving a reduced release of pro-inflammatory cytokines. In a model of metabolic disruption in response to treatment with high lipids and fructose, sc-liver organoids exhibit hallmarks of steatosis and insulin resistance, while sc-islets produce pro-inflammatory cytokines on-chip. Finally, the platform reproduces known effects of anti-diabetic drugs on-chip. Taken together, the platform provides a basis for functional studies of obesity, T2DM, and MASLD on-chip, as well as for testing potential therapeutic interventions.

Exercise-Mediated Protection against Air Pollution-Induced Immune Damage: Mechanisms, Challenges, and Future Directions

Air pollution, a serious risk factor for human health, can lead to immune damage and various diseases. Long-term exposure to air pollutants can trigger oxidative stress and inflammatory responses (the main sources of immune impairment) in the body. Exercise has been shown to modulate anti-inflammatory and antioxidant statuses, enhance immune cell activity, as well as protect against immune damage caused by air pollution. However, the underlying mechanisms involved in the protective effects of exercise on pollutant-induced damage and the safe threshold for exercise in polluted environments remain elusive. In contrast to the extensive research on the pathogenesis of air pollution and the preventive role of exercise in enhancing fitness, investigations into exercise resistance to injury caused by air pollution are still in their infancy. In this review, we analyze evidence from humans, animals, and cell experiments on the combined effects of exercise and air pollution on immune health outcomes, with an emphasis on oxidative stress, inflammatory responses, and immune cells. We also propose possible mechanisms and directions for future research on exercise resistance to pollutant-induced damage in the body. Furthermore, we suggest strengthening epidemiological studies at different population levels and investigations on immune cells to guide how to determine the safety thresholds for exercise in polluted environments.

Unveiling the Silent Intruder: H. pylori's Hidden Link to Ischemic Heart Disease

Cardiovascular disease is the leading cause of death. In addition to the well-known risk factors associated with cardiovascular disease, such as age, diabetes mellitus, smoking, hypertension, and obesity, there has been a growing concern regarding cardiac complications stemming from the Gram-negative bacteria Helicobacter pylori. While H. pylori is most commonly associated with chronic gastritis, peptic ulcer disease, gastric adenocarcinoma, and gastric lymphoma, it has also been implicated in extra gastric manifestations, encompassing cardiac, neurologic, ocular, and dermatologic issues. Key virulent factors for coronary artery disease include the vacuolating cytotoxin gene A and the cytotoxin-associated gene A. The most likely pathogenic mechanism of the relationship between H. pylori and coronary artery disease is initiating a chronic inflammatory process associated with infection and the modifications of classic risk factors. These alterations lead to the creation of prothrombotic and procoagulant environments. Here, we review the cardiac manifestations of H. pylori and the underlying pathophysiological mechanisms.

Memantine Improves Memory and Neurochemical Damage in a Model of Maple Syrup Urine Disease

Maple Syrup Urine Disease (MSUD) is a metabolic disease characterized by the accumulation of branched-chain amino acids (BCAA) in different tissues due to a deficit in the branched-chain alpha-ketoacid dehydrogenase complex. The most common symptoms are poor feeding, psychomotor delay, and neurological damage. However, dietary therapy is not effective. Studies have demonstrated that memantine improves neurological damage in neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. Therefore, we hypothesize that memantine, an NMDA receptor antagonist can ameliorate the effects elicited by BCAA in an MSUD animal model. For this, we organized the rats into four groups: control group (1), MSUD group (2), memantine group (3), and MSUD + memantine group (4). Animals were exposed to the MSUD model by the administration of BCAA (15.8 µL/g) (groups 2 and 4) or saline solution (0.9%) (groups 1 and 3) and treated with water or memantine (5 mg/kg) (groups 3 and 4). Our results showed that BCAA administration induced memory alterations, and changes in the levels of acetylcholine in the cerebral cortex. Furthermore, induction of oxidative damage and alterations in antioxidant enzyme activities along with an increase in pro-inflammatory cytokines were verified in the cerebral cortex. Thus, memantine treatment prevented the alterations in memory, acetylcholinesterase activity, 2',7'-Dichlorofluorescein oxidation, thiobarbituric acid reactive substances levels, sulfhydryl content, and inflammation. These findings suggest that memantine can improve the pathomechanisms observed in the MSUD model, and may improve oxidative stress, inflammation, and behavior alterations.

Evaluation of the Anti-Inflammatory and Antioxidant Potential of Cymbopogon citratus Essential Oil in Zebrafish

This study explored the protective capacity of the essential oil (EO) of Cymbopogon citratus against oxidative stress induced by hydrogen peroxide (H2O2) and the inflammatory potential in zebrafish. Using five concentrations of EO (0.39, 0.78, 1.56, 3.12, and 6.25 μg/mL) in the presence of 7.5 mM H2O2, we analyzed the effects on neutrophil migration, caudal fin regeneration, cellular apoptosis, production of reactive oxygen species (ROS), and activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) after 96 h of exposure. A significant decrease in neutrophil migration was observed in all EO treatments compared to the control. Higher concentrations of EO (3.12 and 6.25 μg/mL) resulted in a significant decrease in caudal fin regeneration compared to the control. SOD activity was reduced at all EO concentrations, CAT activity significantly decreased at 3.12 μg/mL, and GST activity increased at 0.78 μg/mL and 1.56 μg/mL, compared to the control group. No significant changes in ROS production were detected. A reduction in cellular apoptosis was evident at all EO concentrations, suggesting that C. citratus EO exhibits anti-inflammatory properties, influences regenerative processes, and protects against oxidative stress and apoptosis.

Comparative hemolymph proteomic analyses of the freezing and resistance-freezing Ostrinia furnacalis (Guenée)

The Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae), is one of the most harmful pests of maize in Asia. It poses a significant threat to maize production, causing economic losses due to its strong ecological adaptation. In this study, we compared and analyzed the hemolymph proteome between freezing and resistance-freezing O. furnacalis strains using two-dimensional gel electrophoresis to gain insights into the mechanisms of cold resistance. The results revealed that 300-400 hemolymph protein spots were common, with 24 spots showing differences between the two strains. Spectrometry analysis revealed 21 protein spots, including 17 upregulated spots and 4 downregulated ones. The expression of upregulation/downregulation proteins plays a crucial role in the metabolism, energy supply, and defense reaction of insects. Proteomics research not only provides a method for investigating protein expression patterns but also identifies numerous attractive candidates for further exploration.

Cellular Stress Responses against Coronavirus Infection: A Means of the Innate Antiviral Defense

Cellular stress responses are crucial for maintaining cellular homeostasis. Stress granules (SGs), activated by eIF2α kinases in response to various stimuli, play a pivotal role in dealing with diverse stress conditions. Viral infection, as one kind of cellular stress, triggers specific cellular programs aimed at overcoming virus-induced stresses. Recent studies have revealed that virus-derived stress responses are tightly linked to the host's antiviral innate immunity. Virus infection-induced SGs act as platforms for antiviral sensors, facilitating the initiation of protective antiviral responses called "antiviral stress granules" (avSGs). However, many viruses, including coronaviruses, have evolved strategies to suppress avSG formation, thereby counteracting the host's immune responses. This review discusses the intricate relationship between cellular stress responses and antiviral innate immunity, with a specific focus on coronaviruses. Furthermore, the diverse mechanisms employed by viruses to counteract avSGs are described.

Fluoxetine attenuates stress-induced depression-like behavior due to decrease in pro-inflammatory cytokines in male rats

Background: Pro-inflammatory cytokines are implicated in depression caused by both environmental- and alcohol-induced stress. The purpose of the study was to investigate the cytokine levels in serum and hippocampus following induction of depression-like behaviors (DLB) by either forced swimming test (FST) or ethanol-induced DLB (EID). We also investigated the effect of prior administration of antidepressant drug fluoxetine on cytokines in animals exposed to both models of DLB. Methods: Animals were pretreated with fluoxetine before inducing DLB, while DLB was induced in some animals using FST and ethanol in different groups of rats without fluoxetine pretreatment. The ELISA was used to detect changes in cytokine (IL-1β, IL-6, and TNF-α) levels in serum and hippocampus. Results: The mean levels of IL-1β and IL-6 measured in serum and hippocampus were significantly higher in FST and EID models when compared to the control group. The serum concentrations of IL-1β and IL-6 were significantly reduced in animals pre-treated with 5 mg/kg and 10 mg/kg of fluoxetine in both FST and EID models when compared to the untreated FST and EID groups respectively. Conclusions: In conclusion, both environment and alcohol can induce stress and DLB in rats with similar intensity, and their mechanisms of DLB induction involve activation of pro-inflammatory cytokines. Moreover, fluoxetine can prevent stress-induced inflammation in models of DLB.

CRISPR screening in human trophoblast stem cells reveals both shared and distinct aspects of human and mouse placental development

The placenta serves as the interface between the mother and fetus, facilitating the exchange of gases and nutrients between their separate blood circulation systems. Trophoblasts in the placenta play a central role in this process. Our current understanding of mammalian trophoblast development relies largely on mouse models. However, given the diversification of mammalian placentas, findings from the mouse placenta cannot be readily extrapolated to other mammalian species, including humans. To fill this knowledge gap, we performed CRISPR knockout screening in human trophoblast stem cells (hTSCs). We targeted genes essential for mouse placental development and identified more than 100 genes as critical regulators in both human hTSCs and mouse placentas. Among them, we further characterized in detail two transcription factors, DLX3 and GCM1, and revealed their essential roles in hTSC differentiation. Moreover, a gene function-based comparison between human and mouse trophoblast subtypes suggests that their relationship may differ significantly from previous assumptions based on tissue localization or cellular function. Notably, our data reveal that hTSCs may not be analogous to mouse TSCs or the extraembryonic ectoderm (ExE) in which in vivo TSCs reside. Instead, hTSCs may be analogous to progenitor cells in the mouse ectoplacental cone and chorion. This finding is consistent with the absence of ExE-like structures during human placental development. Our data not only deepen our understanding of human trophoblast development but also facilitate cross-species comparison of mammalian placentas.

Genome-wide transcriptional responses of osteoblasts to different titanium surface topographies

This is the first genome-wide transcriptional profiling study using RNA-sequencing to investigate osteoblast responses to different titanium surface topographies, specifically between machined, smooth and acid-etched, microrough surfaces. Rat femoral osteoblasts were cultured on machine-smooth and acid-etched microrough titanium disks. The culture system was validated through a series of assays confirming reduced osteoblast attachment, slower proliferation, and faster differentiation on microrough surfaces. RNA-sequencing analysis of osteoblasts at an early stage of culture revealed that gene expression was highly correlated (r = 0.975) between the two topographies, but 1.38 % genes were upregulated and 0.37 % were downregulated on microrough surfaces. Upregulated transcripts were enriched for immune system, plasma membrane, response to external stimulus, and positive regulation to stimulus processes. Structural mapping confirmed microrough surface-promoted gene sharing and networking in signaling pathways and immune system/responses. Target-specific pathway analysis revealed that Rho family G-protein signaling pathways and actin genes, responsible for the formation of stress fibers, cytoplasmic projections, and focal adhesion, were upregulated on microrough surfaces without upregulation of core genes triggered by cell-to-cell interactions. Furthermore, disulfide-linked or -targeted extracellular matrix (ECM) or membranous glycoproteins such as laminin, fibronectin, CD36, and thrombospondin were highly expressed on microrough surfaces. Finally, proliferating cell nuclear antigen (PCNA) and cyclin D1, whose co-expression reduces cell proliferation, were upregulated on microrough surfaces. Thus, osteoblasts on microrough surfaces were characterized by upregulation of genes related to a wide range of functions associated with the immune system, stress/stimulus responses, proliferation control, skeletal and cytoplasmic signaling, ECM-integrin receptor interactions, and ECM-membranous glycoprotein interactions, furthering our knowledge of the surface-dependent expression of osteoblastic biomarkers on titanium.

Hepatic insulin synthesis increases in rat models of diabetes mellitus type 1 and 2 differently

Insulin-positive (+) cells (IPCs), detected in multiple organs, are of great interest as a probable alternative to ameliorate pancreatic beta-cells dysfunction and insulin deficiency in diabetes. Liver is a potential source of IPCs due to it common embryological origin with pancreas. We previously demonstrated the presence of IPCs in the liver of healthy and diabetic rats, but detailed description and analysis of the factors, which potentially can induced ectopic hepatic expression of insulin in type 1 (T1D) and type 2 diabetes (T2D), were not performed. In present study we evaluate mass of hepatic IPCs in the rat models of T1D and T2D and discuss factors, which may stimulate it generation: glycaemia, organ injury, involving of hepatic stem/progenitor cell compartment, expression of transcription factors and inflammation. Quantity of IPCs in the liver was up by 1.7-fold in rats with T1D and 10-fold in T2D compared to non-diabetic (ND) rats. We concluded that ectopic hepatic expression of insulin gene is activated by combined action of a number of factors, with inflammation playing a decision role.

Excess iron aggravates the severity of COVID-19 infection

Coronavirus disease-19 (COVID-19) can induce severe inflammation of the lungs and respiratory system. Severe COVID-19 is frequently associated with hyper inflammation and hyper-ferritinemia. High iron levels are known to trigger pro-inflammatory effects. Cumulative iron loading negatively impacts on a patients innate immune effector functions and increases the risk for infection related complications. Prognosis of severe acute respiratory SARS-CoV-2 patients may be impacted by iron excess. Iron is an essential co-factor for numerous essential cellular enzymes and vital cellular operations. Viruses hijack cells in order to replicate, and efficient replication requires an iron-replete host. Utilizing iron loaded cells in culture we evaluated their susceptibility to infection by pseudovirus expressing the SARS-CoV-2 spike protein and resultant cellular inflammatory response. We observed that, high levels of iron enhanced host cell ACE2 receptor expression contributing to higher infectivity of pseudovirus. In vitro Cellular iron overload also synergistically enhanced the levels of; reactive oxygen species, reactive nitrogen species, pro-inflammatory cytokines (IL-1β, IL-6, IL-8 & TNF-α) and chemokine (CXCL-1&CCL-4) production in response to inflammatory stimulation of cells with spike protein. These results were confirmed using an in vivo mouse model. In future, limiting iron levels may be a promising adjuvant strategy in treating viral infection.

Fucoidan from Ericaria crinita Alleviates Inflammation in Rat Paw Edema, Downregulates Pro-Inflammatory Cytokine Levels, and Shows Antioxidant Activity

Fucoidans are sulfated polysaccharides detected mainly in the cell walls of brown seaweeds. Here, we examined the effects of single doses of fucoidan derived from Ericaria crinita (formerly Cystoseira crinita) on carrageenan-induced paw inflammation in rats. The serum levels of TNF-α, IL-1β, IL-6, and IL-10 of rats with LPS-induced systemic inflammation after 14 days of treatment were also evaluated. Subchronic treatment with fucoidan from E. crinita attenuated the inflammation during the late phase of the degraded carrageenan-induced paw edema (3rd to 5th hour after carrageenan injection) with peak activity at the 3rd hour after the application. Both doses of fucoidan from E. crinita (25 and 50 mg/kg bw) significantly decreased the levels of all tested pro-inflammatory cytokines (IL-1β, TNF-α, and IL-6) in the serum of rats with a model of system inflammation but had no effect on the anti-inflammatory cytokine IL-10. The results showed that the repeated application of fucoidan has a more prominent effect on the levels of some pro-inflammatory cytokines in serum in comparison to a single dose of the sulfated polysaccharide. This reveals the potential of E. crinita fucoidan as an anti-inflammatory agent. Furthermore, E. crinita fucoidan exhibited in vitro antioxidant capacity, determined by 2,2-diphenyl-1-picryl-hydrazyl radical scavenging and ferric reducing antioxidant power assays as follows: IC50 = 412 µg/mL and 118.72 μM Trolox equivalent/g, respectively.

Ginsenosides for therapeutically targeting inflammation through modulation of oxidative stress

Ginsenosides are steroid glycosides derived from ginseng plants such as Panax ginseng, Panax quinquefolium, and Panax notoginseng. Advances in recent studies have identified numerous physiological functions of each type of ginsenoside, i.e., immunomodulatory, antioxidative, and anti-inflammatory functions, in the context of inflammatory diseases. Accumulating evidence has revealed the molecular mechanisms by which the single or combined ginsenoside(s) exhibit anti-inflammatory effects, although it remains largely unclear. It is well known that excessive production of reactive oxygen species (ROS) is associated with pathological inflammation and cell death in a variety of cells, and that inhibition of ROS generation ameliorates the local and systemic inflammatory responses. The mechanisms by which ginsenosides attenuate inflammation are largely unknown; however, targeting ROS is suggested as one of the crucial mechanisms for the ginsenosides to control the pathological inflammation in the immune and non-immune cells. This review will summarize the latest progress in ginsenoside studies, particularly in the context of antioxidant mechanisms for its anti-inflammatory effects. A better understanding of the distinct types and the combined action of ginsenosides will pave the way for developing potential preventive and therapeutic modalities in treating various inflammation-related diseases.

Acute effects of intracerebroventricular administration of α-ketoisocaproic acid in young rats on inflammatory parameters

Maple Syrup Urine Disease (MSUD) is an autosomal recessive inborn error of metabolism (IEM), responsible for the accumulation of the branched-chain amino acids (BCAA) leucine, isoleucine, and valine, in addition to their α-keto acids α-ketoisocaproic acid (KIC), α-keto-β-methylvaleric acid (KMV), and α-ketoisovaleric acid (KIV) in the plasma and urine of patients. This process occurs due to a partial or total blockage of the dehydrogenase enzyme activity of branched-chain α-keto acids. Oxidative stress and inflammation are conditions commonly observed on IEM, and the inflammatory response may play an essential role in the pathophysiology of MSUD. We aimed to investigate the acute effect of intracerebroventricular (ICV) administration of KIC on inflammatory parameters in young Wistar rats. For this, sixteen 30-day-old male Wistar rats receive ICV microinjection with 8 µmol KIC. Sixty minutes later, the animals were euthanized, and the cerebral cortex, hippocampus, and striatum structures were collected to assess the levels of pro-inflammatory cytokines (INF-γ; TNF-α, IL-1β). The acute ICV administration of KIC increased INF-γ levels in the cerebral cortex and reduced the levels of INF-γ and TNF-α in the hippocampus. There was no difference in IL-1β levels. KIC was related to changes in the levels of pro-inflammatory cytokines in the brain of rats. However, the inflammatory mechanisms involved in MSUD are poorly understood. Thus, studies that aim to unravel the neuroinflammation in this pathology are essential to understand the pathophysiology of this IEM.

Protective effects of Pudilan Tablets against osteoarthritis in mice induced by monosodium iodoacetate

Osteoarthritis (OA) is a complicated disorder that is the most prevalent chronic degenerative joint disease nowadays. Pudilan Tablets (PDL) is a prominent traditional Chinese medicine formula used in clinical settings to treat chronic inflammatory illnesses. However, there is currently minimal fundamental research on PDL in the therapy of joint diseases. As a result, this study looked at the anti-inflammatory and anti-OA properties of PDL in vitro and in vivo, as well as the mechanism of PDL in the treatment of OA. We investigated the anti-OA properties of PDL in OA mice that were generated by monosodium iodoacetate (MIA). All animals were administered PDL (2 g/kg or 4 g/kg) or the positive control drug, indomethacin (150 mg/kg), once daily for a total of 28 days starting on the day of MIA injection. The CCK-8 assay was used to test the vitality of PDL-treated RAW264.7 cells in vitro. RAW264.7 cells that had been activated with lipopolysaccharide (LPS) were used to assess the anti-inflammatory properties of PDL. In the MIA-induced OA model mice, PDL reduced pain, decreased OA-induced cartilage damages and degradation, decreased production of pro-inflammatory cytokines in serum, and suppressed IL-1β, IL-6, and TNF-α mRNA expression levels in tibiofemoral joint. In RAW264.7 cells, PDL treatment prevented LPS-induced activation of the ERK/Akt signaling pathway and significantly decreased the levels of inflammatory cytokines, such as IL-1β, IL-6, and TNF-α. In conclusion, these results suggest that PDL is involved in combating the development and progression of OA, exerts a powerful anti-inflammatory effect on the knee joint, and may be a promising candidate for the treatment of OA.

The Landscape of Expressed Chimeric Transcripts in the Blood of Severe COVID-19 Infected Patients

The ongoing COVID-19 pandemic caused by SARS-CoV-2 infections has quickly developed into a global public health threat. COVID-19 patients show distinct clinical features, and in some cases, during the severe stage of the condition, the disease severity leads to an acute respiratory disorder. In spite of several pieces of research in this area, the molecular mechanisms behind the development of disease severity are still not clearly understood. Recent studies demonstrated that SARS-CoV-2 alters the host cell splicing and transcriptional response to overcome the host immune response that provides the virus with favorable conditions to replicate efficiently within the host cells. In several disease conditions, aberrant splicing could lead to the development of novel chimeric transcripts that could promote the functional alternations of the cell. As severe SARS-CoV-2 infection was reported to cause abnormal splicing in the infected cells, we could expect the generation and expression of novel chimeric transcripts. However, no study so far has attempted to check whether novel chimeric transcripts are expressed in severe SARS-CoV-2 infections. In this study, we analyzed several publicly available blood transcriptome datasets of severe COVID-19, mild COVID-19, other severe respiratory viral infected patients, and healthy individuals. We identified 424 severe COVID-19 -specific chimeric transcripts, 42 of which were recurrent. Further, we detected 189 chimeric transcripts common to severe COVID-19 and multiple severe respiratory viral infections. Pathway and gene enrichment analysis of the parental genes of these two subsets of chimeric transcripts reveals that these are potentially involved in immune-related processes, interferon signaling, and inflammatory responses, which signify their potential association with immune dysfunction leading to the development of disease severity. Our study provides the first detailed expression landscape of chimeric transcripts in severe COVID-19 and other severe respiratory viral infections.

Differential gene expression analysis using RNA-seq in the blood of goats exposed to transportation stress

Transportation stress causes significant changes in physiological responses in goats; however, studies exploring the transcriptome of stress are very limited. The objective of this study was to determine the differential gene expressions and related pathways in the blood samples using RNA-seq procedure in Spanish goats subjected to different durations of transportation stress. Fifty-four male Spanish goats (8-mo old; BW = 29.7 ± 2.03 kg) were randomly subjected to one of three treatments (TRT; n = 18 goats/treatment): (1) transported for 180 min, (2) transported for 30 min, or (3) held in pens (control). Blood samples were collected before and after treatment for stress hormone, metabolite, and transcriptomic analysis. RNA-seq technology was used to obtain the transcriptome profiles of blood. Analysis of physiological data using SAS showed that plasma cortisol concentrations were higher (P < 0.01) in 180 min and 30 min groups compared to the control group. Enrichment analysis of DEGs related to transportation stress through Gene Ontology and KEGG databases revealed that the differentially expressed genes related to inflammatory pathways, caspases, and apoptosis such as IL1R2, CASP14, CD14, TLR4, and MAPK14 were highly enriched in the transported group of goats compared to non-transported goats. Stress in goats leads to a sequence of events at cellular and molecular levels that causes inflammation and apoptosis.

Adverse Drug Reactions during COVID-19 Treatment: A Comprehensive Analysis Focused on Hospitalized Patients, with the Use of a Survey in Cuba in 2020

Aims

To evaluate the prevalence and type of adverse drug reactions (ADRs), together with associated risk factors, among Cuban COVID-19 patients treated with chloroquine (CQ), lopinavir/ritonavir (LPV/r), or interferon α2b (IFN α2b), according to the Cuban protocol.

Materials and Methods

A prospective descriptive analysis of ADRs was performed on 200 COVID-19 patients who were admitted consecutively to three hospitals in Havana and Pinar del Río from April to July 2020. Information on demographics, ADRs, outcomes, behavioral, and health-related factors was collected using a validated questionnaire and clinical records. Each potential ADR case was assessed for causality based on the WHO-UMC algorithm, concomitant drug influences, and the presence of any drug-drug interactions (DDI).

Results

The total frequency of ADRs was 55%, with predominantly gastrointestinal disorders and general symptoms (23% vs 20%). 95.1% of ADRs occurred within 10 days after treatment and 42 potential DDI in 55.5% of patients (61/110) were observed. The prevalence of ADRs was: 44%, 30.4%, and 26.4% for IFN α2b, LPV/r, and CQ, respectively. Sex (odds ratio (OR): 0.40 (95% confidence interval (CI): 0.211-0.742), age (OR: 2.36 (95% CI: 1.02-5.44)), and underlying diseases (OR: 0.12 (95% CI: 0.06-0.23)) were independently associated factors for ADRs (P < 0.05).

Conclusions

The frequency of ADRs and potential DDI was high compared to their use during nonpandemic times (e.g., for malaria, HIV, or inflammatory diseases). The safety profile of these drugs when used for COVID-19 treatment showed similar characteristics. Comorbidities, age >37 years old, and female sex were associated with ADRs.

Clostridium butyricum alleviates LPS-induced acute immune stress in goats by regulating bacterial communities and blood metabolites

The mitigation and prevention of acute immune stress are essential for livestock production. Clostridium butyricum (C. butyricum) has shown positive effects in stabilizing intestinal microbiota disorders, improving immune function and inhibiting disease development, but its effects on ruminants are unclear. Therefore, the current trial hypothesized that C. butyricum could improve goats' immune function and antioxidant capacity by regulating bacterial communities and blood metabolism and effectively alleviating the acute immune stress induced by Lipopolysaccharides (LPS). Sixteen healthy goats were fed C. butyricum for 70 days, and the goats were challenged with LPS on day 71. Blood and feces were collected at 0 h and 6 h after the challenge to evaluate the effects of C. butyricum on their intestinal microbiota, immune function, antioxidant function, and plasma metabolites. The results showed that C. butyricum had no significant effect on plasma biochemical parameters at the beginning of the LPS challenge. However, supplementation with C. butyricum increased plasma levels of IgA, IgG, T-SOD, and T-AOC (P < 0.05), but TNF-α, IL-6, and MDA were decreased (P < 0.05). In contrast, IL-10 showed an increasing trend (P < 0.10). Rectal microbiota analysis showed that C. butyricum significantly increased the relative abundance of Epsilonbacteraeota at the phylum level of goats; at the genus level, the relative abundances of Campylobacter and Anaerorhabdus]_furcosa_group were also significantly increased (P < 0.05). Christensenellaceae_R-7_group as the dominant microbiota also showed a significant increase in their abundance values, while Clostridium and Lachnospiraceae_UCG-001 were significantly lower (P < 0.05). When the LPS challenge continued up to 6 h, dietary supplementation with C. butyricum still resulted in significantly higher plasma concentrations of IgA, IL-10, and T-SOD in goats than in the control group, reducing TNF-α levels (P < 0.05). In addition, plasma levels of T-CHOL and LDL were significantly reduced, and the expression of d-proline was significantly upregulated according to metabolomic analysis (P < 0.05). In conclusion, dietary supplementation with C. butyricum helped optimize the expression of bacterial communities and plasma metabolites to enhance the ability of goats to alleviate acute immune stress.

Structural Characterization and In Vivo Anti-Inflammatory Activity of Fucoidan from Cystoseira crinita (Desf.) Borry

The aim of this study was to evaluate the effects of fucoidan isolated from C. crinita on histamine-induced paw inflammation in rats, and on the serum levels of TNF-α, IL-1β, IL-6, and IL-10 in rats during systemic inflammation response. The levels of TNF-α in a model of acute peritonitis in rats were also investigated. The isolated crude fucoidan was identified as a sulfated xylogalactofucan with high, medium, and low molecular weight fractions and a content of fucose of 39.74%, xylose of 20.75%, and galactose of 15.51%. Fucoidan from C. crinita showed better anti-inflammatory effects in the rat paw edema model, and this effect was present during all stages of the experiment. When compared to controls, a commercial fucoidan from F. vesiculosus, the results also displayed anti-inflammatory activity on the 60th, 90th, and 120th minute of the experiment. A significant decrease in serum levels of IL-1β in rats treated with both doses of C. crinita fucoidan was observed in comparison to controls, whereas TNF-α concentrations were reduced only in the group treated with fucoidan from C. crinita at the dose of 25 mg/kg bw. In the model of carrageenan-induced peritonitis, we observed a tendency of decrease in the levels of the pro-inflammatory cytokine TNF-α in peritoneal fluid after a single dose of C. crinita fucoidan, but this did not reach the statistical significance margin. Single doses of C. crinita fucoidan did not alter serum levels of the anti-inflammatory cytokine IL-10 in animals with lipopolysaccharide-induced systemic inflammation.

Role of Macrophages in Air Pollution Exposure Related Asthma

Asthma is a chronic inflammatory airway disease characterized by variable airflow obstruction, bronchial hyper-responsiveness, and airway inflammation. The chronic inflammation of the airway is mediated by many cell types, cytokines, chemokines, and inflammatory mediators. Research suggests that exposure to air pollution has a negative impact on asthma outcomes in adult and pediatric populations. Air pollution is one of the greatest environmental risks to health, and it impacts the lungs' innate and adaptive defense systems. A major pollutant in the air is particulate matter (PM), a complex component composed of elemental carbon and heavy metals. According to the WHO, 99% of people live in air pollution where air quality levels are lower than the WHO air quality guidelines. This suggests that the effect of air pollution exposure on asthma is a crucial health issue worldwide. Macrophages are essential in recognizing and processing any inhaled foreign material, such as PM. Alveolar macrophages are one of the predominant cell types that process and remove inhaled PM by secreting proinflammatory mediators from the lung. This review focuses on macrophages and their role in orchestrating the inflammatory responses induced by exposure to air pollutants in asthma.

Melanocytotoxic chemicals and their toxic mechanisms

Melanocyte cell death can lead to various melanocyte-related skin diseases including vitiligo and leukoderma. Melanocytotoxic chemicals are one of the most well-known causes of nongenetic melanocyte-related diseases, which induce melanocyte cell death through apoptosis. Various chemicals used in cosmetics, medicine, industry and food additives are known to induce melanocyte cell death, which poses a significant risk to the health of consumers and industrial workers. This review summarizes recently reported melanocytotoxic chemicals and their mechanisms of toxicity in an effort to provide insight into the development of safer chemicals.

Loss of heat shock factor 1 promotes hepatic stellate cell activation and drives liver fibrosis

Liver fibrosis is an aberrant wound healing response that results from chronic injury and is mediated by hepatocellular death and activation of hepatic stellate cells (HSCs). While induction of oxidative stress is well established in fibrotic livers, there is limited information on stress‐mediated mechanisms of HSC activation. Cellular stress triggers an adaptive defense mechanism via master protein homeostasis regulator, heat shock factor 1 (HSF1), which induces heat shock proteins to respond to proteotoxic stress. Although the importance of HSF1 in restoring cellular homeostasis is well‐established, its potential role in liver fibrosis is unknown. Here, we show that HSF1 messenger RNA is induced in human cirrhotic and murine fibrotic livers. Hepatocytes exhibit nuclear HSF1, whereas stellate cells expressing alpha smooth muscle actin do not express nuclear HSF1 in human cirrhosis. Interestingly, despite nuclear HSF1, murine fibrotic livers did not show induction of HSF1 DNA binding activity compared with controls. HSF1‐deficient mice exhibit augmented HSC activation and fibrosis despite limited pro‐inflammatory cytokine response and display delayed fibrosis resolution. Stellate cell and hepatocyte‐specific HSF1 knockout mice exhibit higher induction of profibrogenic response, suggesting an important role for HSF1 in HSC activation and fibrosis. Stable expression of dominant negative HSF1 promotes fibrogenic activation of HSCs. Overactivation of HSF1 decreased phosphorylation of JNK and prevented HSC activation, supporting a protective role for HSF1. Our findings identify an unconventional role for HSF1 in liver fibrosis. Conclusion: Our results show that deficiency of HSF1 is associated with exacerbated HSC activation promoting liver fibrosis, whereas activation of HSF1 prevents profibrogenic HSC activation.

Molecular Mechanisms of Epigenetic Regulation, Inflammation, and Cell Death in ADPKD

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder, which is caused by mutations in the PKD1 and PKD2 genes, characterizing by progressive growth of multiple cysts in the kidneys, eventually leading to end-stage kidney disease (ESKD) and requiring renal replacement therapy. In addition, studies indicate that disease progression is as a result of a combination of factors. Understanding the molecular mechanisms, therefore, should facilitate the development of precise therapeutic strategies for ADPKD treatment. The roles of epigenetic modulation, interstitial inflammation, and regulated cell death have recently become the focuses in ADPKD. Different epigenetic regulators, and the presence of inflammatory markers detectable even before cyst growth, have been linked to cyst progression. Moreover, the infiltration of inflammatory cells, such as macrophages and T cells, have been associated with cyst growth and deteriorating renal function in humans and PKD animal models. There is evidence supporting a direct role of the PKD gene mutations to the regulation of epigenetic mechanisms and inflammatory response in ADPKD. In addition, the role of regulated cell death, including apoptosis, autophagy and ferroptosis, have been investigated in ADPKD. However, there is no consensus whether cell death promotes or delays cyst growth in ADPKD. It is therefore necessary to develop an interactive picture between PKD gene mutations, the epigenome, inflammation, and cell death to understand why inherited PKD gene mutations in patients may result in the dysregulation of these processes that increase the progression of renal cyst formation.

Upwelling-level acidification and pH/pCO2 variability moderate effects of ocean acidification on brain gene expression in the temperate surfperch, Embiotoca jacksoni

Acidification-induced changes in neurological function have been documented in several tropical marine fishes. Here, we investigate whether similar patterns of neurological impacts are observed in a temperate Pacific fish that naturally experiences regular and often large shifts in environmental pH/pCO₂ . In two laboratory experiments, we tested the effect of acidification, as well as pH/pCO₂ variability, on gene expression in the brain tissue of a common temperate kelp forest/estuarine fish, Embiotoca jacksoni. Experiment 1 employed static pH treatments (target pH = 7.85/7.30), while Experiment 2 incorporated two variable treatments that oscillated around corresponding static treatments with the same mean (target pH = 7.85/7.70) in an eight-day cycle (amplitude ± 0.15). We found that patterns of global gene expression differed across pH level treatments. Additionally, we identified differential expression of specific genes and enrichment of specific gene sets (GSEA) in comparisons of static pH treatments and in comparisons of static and variable pH treatments of the same mean pH. Importantly, we found that pH/pCO₂ variability decreased the number of differentially expressed genes detected between high and low pH treatments, and that inter-individual variability in gene expression was greater in variable treatments than static treatments. These results provide important confirmation of neurological impacts of acidification in a temperate fish species and, critically, that natural environmental variability may mediate the impacts of ocean acidification.

Ambivalent Roles of Oxidative Stress in Triangular Relationships among Arthropod Vectors, Pathogens and Hosts

Blood-feeding arthropods, particularly ticks and mosquitoes are considered the most important vectors of arthropod-borne diseases affecting humans and animals. While feeding on blood meals, arthropods are exposed to high levels of reactive oxygen species (ROS) since heme and other blood components can induce oxidative stress. Different ROS have important roles in interactions among the pathogens, vectors, and hosts. ROS influence various metabolic processes of the arthropods and some have detrimental effects. In this review, we investigate the various roles of ROS in these arthropods, including their innate immunity and the homeostasis of their microbiomes, that is, how ROS are utilized to maintain the balance between the natural microbiota and potential pathogens. We elucidate the mechanism of how ROS are utilized to fight off invading pathogens and how the arthropod-borne pathogens use the arthropods’ antioxidant mechanism to defend against these ROS attacks and their possible impact on their vector potentials or their ability to acquire and transmit pathogens. In addition, we describe the possible roles of ROS in chemical insecticide/acaricide activity and/or in the development of resistance. Overall, this underscores the importance of the antioxidant system as a potential target for the control of arthropod and arthropod-borne pathogens.

Protective Effects and Potential Mechanisms of Dietary Resveratrol Supplementation on the Spleen of Broilers Under Heat Stress

Resveratrol (RSV) is a natural polyphenolic compound with potent antioxidant and anti-inflammatory properties. This study aimed to investigate the protective effects of RSV supplementation on the inflammatory responses of broilers during heat stress. A total of 432 28-d-old white-feathered broilers (817 crossbred chicken) with an average weight of 549 ± 4 g were randomly allotted to 4 equal groups (Half male and half female, 6 replicates/group, 18 chickens/replicate), including normal temperature (NT) group (24 ± 2°C for 24 h/d, basal diet), NT+RSV group (24 ± 2°C for 24 h/d, basal diet + RSV), heat stress (HT) group (37 ± 2°C for 8 h/d, basal diet), and HT+RSV group (37 ± 2°C for 8 h/d, basal diet + RSV). Serum samples were collected on d 7 and 14 of heat stress, and thymus, spleen, jejunum, and bursa of Fabricius samples were collected and analyzed on d14. RSV treatment decreased the feed conversion ratio, partially reversed the negative alternations in body weight, average daily gain, and average daily feed intake caused by heat stress. RSV treatment also decreased the elevated levels of corticosterone on d 14, adrenocorticotropic hormone, and triiodothyronine in serum on d 7 caused by heat stress, and significantly increased the villus height to crypt depth ratio in the jejunum on d 14. Dietary RSV also reduced heat stress-induced splenic pro-inflammatory cytokine concentrations. TUNEL assay showed that RSV significantly reduced heat stress-induced the number of apoptotic cells. Remarkably, RSV down-regulated some splenic related genes for apoptosis genes, including BCL-2, Apaf-1, and MDM2 mRNA levels induced by heat stress. According to GO and KEGG enrichment analyses, the differential genes between HT and HT + RSV groups were mainly associated with immune system process, hematopoietic or lymphoid organ development, and toll-like receptor signaling pathway. The relative mRNA expression of NF-κB, heat shock protein 70 (HSP70), and p38 MAPK were markedly decreased by the combination of RSV and heat stress. These findings showed that RSV might reduce the splenic inflammatory response in heat-stressed white-feather broilers by inhibiting heat stress-induced activation of NF-B, MAPK, and HSP70, as well as inhibiting the activation of mitochondrial apoptotic pathways.

Transcriptome analysis of infected Crandell Rees Feline Kidney (CRFK) cells by canine parvovirus type 2c Laotian isolates

The advent of RNA sequencing technology provides insight into the dynamic nature of tremendous transcripts within Crandell-Reese feline kidney (CRFK) cells in response to canine parvovirus (CPV-2c) infection. A total of 1,603 genes displayed differentially expressed genes (DEGs), including 789 up-regulated genes and 814 downregulated genes in the infected cells. Gene expression profiles have shown a subtle pattern of defense mechanism and immune response to CPV through significant DEGs when extensively examined via Gene Ontology (GO) and pathway analysis. Prospective GO analysis was performed and identified several enriched GO biological process terms with significant participating roles in the immune system process and defense response to virus pathway. A Gene network was constructed using the 22 most significantly enriched genes of particular interests in defense response to virus pathways to illustrate the key pathways. Eleven genes (C1QBP, CD40, HYAL2, IFNB1, IFNG, IL12B, IL6, IRF3, LSM14A, MAVS, NLRC5) were identified, which are directly related to the defense response to the virus. Results of transcriptome profiling permit us to understand the heterogeneity of DEGs during in vitro experimental study of CPV infection, reflecting a unique transcriptome signature for the CPV virus. Our findings also demonstrate a distinct scenario of enhanced CPV responses in CRFK cells for viral clearance that involved multistep and perplexity of biological processes. Collectively, our data have given a fundamental role in anti-viral immunity as our highlights of this study, thus providing outlooks on future research priorities to be important in studying CPV.

Inflammation: A New Look at an Old Problem

Pro-inflammatory stress is inherent in any cells that are subject to damage or threat of damage. It is defined by a number of universal components, including oxidative stress, cellular response to DNA damage, unfolded protein response to mitochondrial and endoplasmic reticulum stress, changes in autophagy, inflammasome formation, non-coding RNA response, formation of an inducible network of signaling pathways, and epigenetic changes. The presence of an inducible receptor and secretory phenotype in many cells is the cause of tissue pro-inflammatory stress. The key phenomenon determining the occurrence of a classical inflammatory focus is the microvascular inflammatory response (exudation, leukocyte migration to the alteration zone). This same reaction at the systemic level leads to the development of life-critical systemic inflammation. From this standpoint, we can characterize the common mechanisms of pathologies that differ in their clinical appearance. The division of inflammation into alternative variants has deep evolutionary roots. Evolutionary aspects of inflammation are also described in the review. The aim of the review is to provide theoretical arguments for the need for an up-to-date theory of the relationship between key human pathological processes based on the integrative role of the molecular mechanisms of cellular and tissue pro-inflammatory stress.

NKT-like (CD3 + CD56+) cells differ from T cells in expression level of cellular protective proteins and sensitivity to stimulation in the process of ageing

BACKGROUND

NKT-like cells are T lymphocytes coexpressing several NK cell-associated receptors. They are effector lymphocytes of innate and adaptive immunity, and their number increases with age. The study aimed to analyze the expression of cellular protective proteins, i.e. sirtuin 1 (SIRT1), heat shock protein 70 (HSP70) and manganese superoxide dismutase (SOD2) in NKT-like and T cells of the young ('young', 31 subjects, age range 19-24 years), seniors aged under 85 ('old'; 30 subjects, age range 65-84 years) and seniors aged over 85 ('oldest', 24 subjects, age range 85-94 years). Both NKT-like and T cells were cultured for 48 h and stimulated with IL-2, LPS and PMA with ionomycin and compared with unstimulated control cells.

RESULTS

The oldest seniors varied from the other age groups by significantly increased expression of SIRT1 and HSP70 in both NKT-like and T cells observed in both stimulated and nonstimulated cells. The analyzed lymphocyte populations of the oldest revealed not only the highest expression of these proteins but also insensitivity to all types of applied stimulation. When NKT-like cells were compared to T cells, higher expression of the studied protective proteins was observed in both stimulated and unstimulated NKT-like cells. Neither CD3 + CD56+ nor CD3+ cells revealed elevated expression of SOD2, and these cells responded to stimulation until very advanced age. T cells revealed higher sensitivity to stimulation with IL-2 regarding SIRT1 and HSP70 expression. NKT-like cells were more sensitive to stimulation with PMA and ionomycin concerning the expression of these proteins. IL-2 did not induce a significant increase in SOD2 expression in the studied age groups.

CONCLUSIONS

The oldest seniors developed an adaptive stress response in both T and NKT-like cells regarding the expression of SIRT1 and HSP70, which was increased and insensitive to further stimulation in contrast to SOD2, which showed a more inducible pattern of expression. CD3 + CD56+ cells exhibited higher expression of cellular protective proteins than CD3+ cells in both stimulated and control, nonstimulated cells. NKT-like and T cells showed a distinct sensitivity to the applied stimulatory factors in the respective age groups.

Knockdown of circ_0001679 alleviates lipopolysaccharide-induced MLE-12 lung cell injury by regulating the miR-338-3p/ mitogen-activated protein kinase 1 axis

The upregulation of circ_0001679 was reported in lipopolysaccharide (LPS)-induced lung injury mouse model, but its functional roles and mechanisms in LPS-induced lung injury remain to be investigated. In this study, we aimed to explore the potential role of circ_0001679 in septic acute lung injury. We initially established an in vitro lung cell injury model using LPS-treated MLE-12 cells. siRNAs targeting circRNA_0001679 were employed to stably knock down circRNA_0001679, followed by functional assays to investigate the effect of circRNA_0001679 silencing. The levels of inflammatory cytokines such as IL-6, IL-β and TNF-α (Tumor necrosis factor-α) were detected by ELISA (Enzyme-linked immunosorbent assay). Meanwhile, protein levels of Bcl-2, cleaved-caspase 3, Bax, and MAPK1 (Mitogen-Activated Protein Kinase 1) proteins expression level were measured by Western blot. We found that Circ_0001679 was upregulated in LPS-induced MLE-12 cells, and silencing circ_0001679 attenuated the growth inhibition and suppressed apoptosis induced by LPS. Circ_0001679 knockdown also lowered levels of IL-6, IL-β and TNF-α, and prevent the activation of cleaved-caspase 3 protein. We further revealed that circ_0001679 functioned as a sponge of miR-338-3p to negatively regulate miR-338-3p activity. miR-338-3p downregulated its downstream target MAPK1, while the upregulation of circ_0001679 maintained a high-level expression of MAPK1 by suppressing miR-338-3p. Collectively, our study indicates that circ_0001679/miR-338-3p/MAPK1 axis may play an important role in the pathogenesis of acute lung injury (ALI).

Assessing Fish Immunotoxicity by Means of In Vitro Assays: Are We There Yet?

There is growing awareness that a range of environmental chemicals target the immune system of fish and may compromise the resistance towards infectious pathogens. Existing concepts to assess chemical hazards to fish, however, do not consider immunotoxicity. Over recent years, the application of in vitro assays for ecotoxicological hazard assessment has gained momentum, what leads to the question whether in vitro assays using piscine immune cells might be suitable to evaluate immunotoxic potentials of environmental chemicals to fish. In vitro systems using primary immune cells or immune cells lines have been established from a wide array of fish species and basically from all immune tissues, and in principal these assays should be able to detect chemical impacts on diverse immune functions. In fact, in vitro assays were found to be a valuable tool in investigating the mechanisms and modes of action through which environmental agents interfere with immune cell functions. However, at the current state of knowledge the usefulness of these assays for immunotoxicity screening in the context of chemical hazard assessment appears questionable. This is mainly due to a lack of assay standardization, and an insufficient knowledge of assay performance with respect to false positive or false negative signals for the different toxicant groups and different immune functions. Also the predictivity of the in vitro immunotoxicity assays for the in vivo immunotoxic response of fishes is uncertain. In conclusion, the currently available database is too limited to support the routine application of piscine in vitro assays as screening tool for assessing immunotoxic potentials of environmental chemicals to fish.

NLRP3 inflammasome of microglia promotes A1 astrocyte transformation, neo-neuron decline and cognition impairment in endotoxemia

Infection, predominantly induced by gram-negative bacteria, is a critical health problem and a leading cause of death worldwide. Advance of techniques, such as antibiotics and life-supporting modality, allows a decreasing death rate of patients with infection in recent decades. Nevertheless, infection-associated complications, in particular cognitive dysfunction, largely influence the mortality of patients and the life quality of survivors. However, the effective medicine is still scant due to the poor interpretion of underlying mechanisms. Herein, we determined multiple cytokines of cerebrospinal fluid in mice challenged with various doses of lipopolysaccharides (LPS)-a pathogenic component of gram-negative bacteria, and found that IL-1β, the downstream of NLRP3 inflammasome, was boosted to a peak extent after a challenge of LPS in high dose. Genetically knockout of Nlrp3 or the downstreams, such as Asc and Gsdmd, dramatically restored LPS-induced cognitive impairment, which was attributed to inhibiting microglia-induced A1 astrocytes and so-caused neo-neuron decline. Taken together, NLRP3 inflammasome of microglia promotes transformation of A1 astrocytes and consequently exacerbates neo-neuron decline, resulting in cognitive impairment after a challenge of LPS. Our study thus discovers a novel understanding in the pathogenesis of LPS-induced cognitive dysfunction, and indicates that NLRP3 inflammasome would be a promising target in the treatment of the syndrome.

The innate immune system and fever under redox control: A Narrative Review

ABSTRACT:

In living cells, redox potential is vitally important for normal physiological processes that are closely regulated by antioxidants, free amino acids and proteins that either have reactive oxygen and nitrogen species capture capability or can be compartmentalized. Although hundreds of experiments support the regulatory role of free radicals and their derivatives, several authors continue to claim that these perform only harmful and non-regulatory functions. In this paper we show that countless intracellular and extracellular signal pathways are directly or indirectly linked to regulated redox processes. We also briefly discuss how artificial oxidative stress can have important therapeutic potential and the possible negative effects of popular antioxidant supplements.

Proteomic landscape of SARS-CoV-2– and MERS-CoV–infected primary human renal epithelial cells

Translatome and proteome analyses of human proximal and distal tubular cells during coronavirus infection reveal distinctive host cell response patterns important for viral replication and renal pathology.

Acute kidney injury is associated with mortality in COVID-19 patients. However, host cell changes underlying infection of renal cells with SARS-CoV-2 remain unknown and prevent understanding of the molecular mechanisms that may contribute to renal pathology. Here, we carried out quantitative translatome and whole-cell proteomics analyses of primary renal proximal and distal tubular epithelial cells derived from human donors infected with SARS-CoV-2 or MERS-CoV to disseminate virus and cell type–specific changes over time. Our findings revealed shared pathways modified upon infection with both viruses, as well as SARS-CoV-2-specific host cell modulation driving key changes in innate immune activation and cellular protein quality control. Notably, MERS-CoV infection–induced specific changes in mitochondrial biology that were not observed in response to SARS-CoV-2 infection. Furthermore, we identified extensive modulation in pathways associated with kidney failure that changed in a virus- and cell type–specific manner. In summary, we provide an overview of the effects of SARS-CoV-2 or MERS-CoV infection on primary renal epithelial cells revealing key pathways that may be essential for viral replication.

Eliminating chronic myeloid leukemia stem cells by IRAK1/4 inhibitors

Leukemia stem cells (LSCs) in chronic myeloid leukemia (CML) are quiescent, insensitive to BCR-ABL1 tyrosine kinase inhibitors (TKIs) and responsible for CML relapse. Therefore, eradicating quiescent CML LSCs is a major goal in CML therapy. Here, using a G₀ marker (G₀M), we narrow down CML LSCs as G₀M- and CD27- double positive cells among the conventional CML LSCs. Whole transcriptome analysis reveals NF-κB activation via inflammatory signals in imatinib-insensitive quiescent CML LSCs. Blocking NF-κB signals by inhibitors of interleukin-1 receptor-associated kinase 1/4 (IRAK1/4 inhibitors) together with imatinib eliminates mouse and human CML LSCs. Intriguingly, IRAK1/4 inhibitors attenuate PD-L1 expression on CML LSCs, and blocking PD-L1 together with imatinib also effectively eliminates CML LSCs in the presence of T cell immunity. Thus, IRAK1/4 inhibitors can eliminate CML LSCs through inhibiting NF-κB activity and reducing PD-L1 expression. Collectively, the combination of TKIs and IRAK1/4 inhibitors is an attractive strategy to achieve a radical cure of CML.

Single nucleotide polymorphism rs 2070874 at Interleukin-4 is associated with increased risk of type 1 diabetes mellitus independently of human leukocyte antigens

Introduction

Type 1 diabetes mellitus (T1DM) is characterized by autoimmune destruction of insulin-producing pancreatic beta (β-) cells. Previous studies suggested an imbalance between and pro- and anti-inflammatory cytokines exacerbates T1DM development.

Objectives

We aimed to test the hypothesis that patients with T1DM carry a higher frequency of regulatory genes associated with low levels of the anti-inflammatory cytokines interleukin-4 (IL-4), its receptor (IL-4R), and interleukin-10 (IL-10).

Methods

Accordingly, we compared frequencies of five different single nucleotide polymorphisms (SNPs) in T1DM patients and healthy controls who had been typed for HLA-DRB1, HLA-DQA1, and HLA-DQB1 genes.

Results

The frequencies of rs2070874 (IL-4) alleles C and T differed between T1DM patients and controls (^cp = 0.0065), as did their codominant (^cp = 0.026) and recessive (^cp = 0.015) models. Increased frequencies were observed in T1DM patients for HLA alleles: DRB1*03 (pc < 0.0013), DRB1*04 (^cp = 0.0169), DQA1*03 (^cp = 0.0222), DQA1*05 (^cp < 0.0006), DQB1*02 (^cp = 0.0005), and DQB1*06 (^cp < 0.0005). And lower frequencies were observed for: DRB1*07 (^cp = 0.0078), DRB1*11 (^cp = 0.0013), DRB1*13 (^cp < 0.0364), DRB1*15 (^cp < 0.0013), DQA1*01 (^cp < 0.0006), and DQA1*02 (^cp = 0.0348). Certain DRB1: DQA1: DQB1 haplotypes showed greater frequencies, including, 03:05:02 (p < 0.0001) and 04:03:03 (p = 0.0017), whereas others showed lower frequencies, including, 07:02:02 (p = 0.0032), 11:05:03 (p = 0.0007), and 15:01:06 (p = 0.0002). Stratification for the above HLA haplotypes with rs2070874 C/C exhibited no significant differences between T1DM patients overall and controls. However, when stratified for the vulnerable HLA haplotype (03:05:02/04:03:03), young patients in whom T1DM began at ≤13 years had a higher frequency of the SNP (rs2070874 C/C); a gene associated with low IL-4 production (p < 0.024).

Conclusion

This study suggests that possession of the rs2070874 C/C genotype, which is associated with low production of IL-4, increases the risk of T1DM in young individuals carrying vulnerable HLA alleles/haplotypes.

Elevated temperature inhibits SARS-CoV-2 replication in respiratory epithelium independently of IFN-mediated innate immune defenses

The pandemic spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiological agent of Coronavirus Disease 2019 (COVID-19), represents an ongoing international health crisis. A key symptom of SARS-CoV-2 infection is the onset of fever, with a hyperthermic temperature range of 38 to 41°C. Fever is an evolutionarily conserved host response to microbial infection that can influence the outcome of viral pathogenicity and regulation of host innate and adaptive immune responses. However, it remains to be determined what effect elevated temperature has on SARS-CoV-2 replication. Utilizing a three-dimensional (3D) air-liquid interface (ALI) model that closely mimics the natural tissue physiology of SARS-CoV-2 infection in the respiratory airway, we identify tissue temperature to play an important role in the regulation of SARS-CoV-2 infection. Respiratory tissue incubated at 40°C remained permissive to SARS-CoV-2 entry but refractory to viral transcription, leading to significantly reduced levels of viral RNA replication and apical shedding of infectious virus. We identify tissue temperature to play an important role in the differential regulation of epithelial host responses to SARS-CoV-2 infection that impact upon multiple pathways, including intracellular immune regulation, without disruption to general transcription or epithelium integrity. We present the first evidence that febrile temperatures associated with COVID-19 inhibit SARS-CoV-2 replication in respiratory epithelia. Our data identify an important role for tissue temperature in the epithelial restriction of SARS-CoV-2 independently of canonical interferon (IFN)-mediated antiviral immune defenses.

Clostridium butyricum Alleviates Enterotoxigenic Escherichia coli K88-Induced Oxidative Damage Through Regulating the p62-Keap1-Nrf2 Signaling Pathway and Remodeling the Cecal Microbial Community

Clostridium butyricum (CB) can enhance antioxidant capacity and alleviate oxidative damage, but the molecular mechanism by which this occurs remains unclear. This study used enterotoxigenic Escherichia coli (ETEC) K88 as a pathogenic model, and the p62-Keap1-Nrf2 signaling pathway and intestinal microbiota as the starting point to explore the mechanism through which CB alleviates oxidative damage. After pretreatment with CB for 15 d, mice were challenged with ETEC K88 for 24 h. The results suggest that CB pretreatment can dramatically reduce crypt depth (CD) and significantly increase villus height (VH) and VH/CD in the jejunum of ETEC K88-infected mice and relieve morphological lesions of the liver and jejunum. Additionally, compared with ETEC-infected group, pretreatment with 4.4×10⁶ CFU/mL CB can significantly reduce malondialdehyde (MDA) level and dramatically increase superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels in the serum. This pretreatment can also greatly increase the mRNA expression levels of tight junction proteins and genes related to the p62-Keap1-Nrf2 signaling pathway in the liver and jejunum in ETEC K88-infected mice. Meanwhile, 16S rDNA amplicon sequencing revealed that Clostridium disporicum was significantly enriched after ETEC K88 challenge relative to the control group, while Lactobacillus was significantly enriched after 4.4×10⁶ CFU/mL CB treatment. Furthermore, 4.4×10⁶ CFU/mL CB pretreatment increased the short-chain fatty acid (SCFA) contents in the cecum of ETEC K88-infected mice. Moreover, we found that Lachnoclostridium, Roseburia, Lactobacillus, Terrisporobacter, Akkermansia, and Bacteroides are closely related to SCFA contents and oxidative indicators. Taken together, 4.4×10⁶ CFU/mL CB pretreatment can alleviate ETEC K88-induced oxidative damage through activating the p62-Keap1-Nrf2 signaling pathway and remodeling the cecal microbiota community in mice.

Psychological Trauma in the Context of Intimate Partner Violence: A Concept Analysis

A comprehensive understanding of psychological trauma in the context of intimate partner violence (IPV) is relevant for nurses and other healthcare providers to provide better care for individuals and families confronting this issue. A concept analysis based on Walker and Avant was conducted to fully understand this concept and its impact on physical and mental health. This concept analysis demonstrates that psychological trauma in the IPV context is an intricate multi-faceted concept that can have a significant long-term effect on individuals who have experienced IPV. The concept's attributes, antecedents, and consequences identified in this concept analysis will contribute to guiding practice, research, education, and policy development aimed to address the trauma affecting individuals and families in the context of IPV.

Molecular mechanisms of heat shock factor 1 regulation

To thrive and to fulfill their functions, cells need to maintain proteome homeostasis even in the face of adverse environmental conditions or radical restructuring of the proteome during differentiation. At the center of the regulation of proteome homeostasis is an ancient transcriptional mechanism, the so-called heat shock response (HSR), orchestrated in all eukaryotic cells by heat shock transcription factor 1 (Hsf1). As Hsf1 is implicated in aging and several pathologies like cancer and neurodegenerative disorders, understanding the regulation of Hsf1 could open novel therapeutic opportunities. In this review, we discuss the regulation of Hsf1's transcriptional activity by multiple layers of control circuits involving Hsf1 synthesis and degradation, conformational rearrangements and post-translational modifications (PTMs), and molecular chaperones in negative feedback loops.

ATF6-DGAT pathway is involved in TLR7-induced innate immune response in Ctenopharyngodon idellus kidney cells

DGAT1 and DGAT2 are two acyl-CoA:diacylglycerol O-acyltransferase (DGAT) enzymes that catalyze the final step in triglyceride (TG) synthesis. TGs are the primary constituents of lipid droplets (LDs). Although it has been demonstrated that LDs modulate immune and inflammatory responses in CIK cells, little is known about whether DGAT1 and DGAT2 involve in this process. Firstly, grass carp DGAT2 was isolated and characterized, encoding 361 amino acids, and all DGAT2 proteins in genomic structures are conserved in vertebrates. Then, using TLR7 agonist, we induced LDs accumulation in CIK cells. Only DGAT1b and DGAT2 were upregulated in forming TLR7 agonist induced-LDs. Next, we utilized small-molecule inhibitors of DGAT1 and DGAT2. The results indicated that DGAT1 inactivation attenuated TG content and the relative expressions of IFNα3, NF-κB, IL-1β, and TNFα genes, whereas DGAT2 inhibition decreased TG content and the relative expressions of MyD88, IRF7, IFNα3, NF-κB, IL-1β, and TNFα genes, implying that DGAT1-generated LDs and DGAT2-generated LDs contribute to TLR7-induced immune response via different signaling pathways. Finally, inhibiting ATF6 effectively decreased DGAT-generated LDs accumulation and the expression of TLR7 signaling-related genes induced by TLR7 agonist, implying that ATF6 UPR pathway may mediate the role of DGAT-generated LDs in TLR7 signaling. Overall, we demonstrate that DGAT1 and DGAT2-catalyzed TAG synthesis may generate different LDs to provide distinct signaling platforms for innate TLR7 signaling.

Clarifying the molecular mechanism of tomentosin‑induced antiproliferative and proapoptotic effects in human multiple myeloma via gene expression profile and genetic interaction network analysis

Multiple myeloma (MM) is an aggressive B cell malignancy. Substantial progress has been made in the therapeutic context for patients with MM, however it still represents an incurable disease due to drug resistance and recurrence. Development of more effective or synergistic therapeutic approaches undoubtedly represents an unmet clinical need. Tomentosin is a bioactive natural sesquiterpene lactone extracted by various plants with therapeutic properties, including anti-neoplastic effects. In the present study, the potential antitumor activity of tomentosin was evaluated on the human RPMI-8226 cell line, treated with increasing tomentosin concentration for cytotoxicity screening. The data suggested that both cell cycle arrest and cell apoptosis could explain the antiproliferative effects of tomentosin and may result in the inhibition of RPMI-8226 cell viability. To assess differentially expressed genes contributing to tomentosin activity and identify its mechanism of action, a microarray gene expression profile was performed, identifying 126 genes deregulated by tomentosin. To address the systems biology and identify how tomentosin deregulates gene expression in MM from a systems perspective, all deregulated genes were submitted to enrichment and molecular network analysis. The Protein-Protein Interaction (PPI) network analysis showed that tomentosin in human MM induced the downregulation of genes involved in several pathways known to lead immune-system processes, such as cytokine-cytokine receptor interaction, chemokine or NF-κB signaling pathway, as well as genes involved in pathways playing a central role in cellular neoplastic processes, such as growth, proliferation, migration, invasion and apoptosis. Tomentosin also induced endoplasmic reticulum stress via upregulation of cyclic AMP-dependent transcription factor ATF-4 and DNA damage-inducible transcript 3 protein genes, suggesting that in the presence of tomentosin the protective unfolded protein response signaling may induce cell apoptosis. The functional connections analysis executed using the Connectivity Map tool, suggested that the effects of tomentosin on RPMI-8226 cells might be similar to those exerted by heat shock proteins inhibitors. Taken together, these data suggested that tomentosin may be a potential drug candidate for the treatment of MM.

Exercise duration modulates upper and lower respiratory fluid cellularity, antiviral activity, and lung gene expression

Exercise has substantial health benefits, but the effects of exercise on immune status and susceptibility to respiratory infections are less clear. Furthermore, there is limited research examining the effects of prolonged exercise on local respiratory immunity and antiviral activity. To assess the upper respiratory tract in response to exercise, we collected nasal lavage fluid (NALF) from human subjects (1) at rest, (2) after 45 min of moderate-intensity exercise, and (3) after 180 min of moderate-intensity exercise. To assess immune responses of the lower respiratory tract, we utilized a murine model to examine the effect of exercise duration on bronchoalveolar lavage (BAL) fluid immune cell content and lung gene expression. NALF cell counts did not change after 45 min of exercise, whereas 180 min significantly increased total cells and leukocytes in NALF. Importantly, fold change in NALF leukocytes correlated with the post-exercise fatigue rating in the 180-min exercise condition. The acellular portion of NALF contained strong antiviral activity against Influenza A in both resting and exercise paradigms. In mice undergoing moderate-intensity exercise, BAL total cells and neutrophils decreased in response to 45 or 90 min of exercise. In lung lobes, increased expression of heat shock proteins suggested that cellular stress occurred in response to exercise. However, a broad upregulation of inflammatory genes was not observed, even at 180 min of exercise. This work demonstrates that exercise duration differentially alters the cellularity of respiratory tract fluids, antiviral activity, and gene expression. These changes in local mucosal immunity may influence resistance to respiratory viruses, including influenza or possibly other pathogens in which nasal mucosa plays a protective role, such as rhinovirus or SARS-CoV-2.