Exercise immunology:Novel insights

The coronavirus disease 2019(COVID-19)pandemic heightened worldwide attention on the influence of exercise on the immune system.Questions were raised about whether regular moderate-to-vigorous physical activity(MVPA)could help prevent COVID-19 or mitigate symptoms when ill.Could MVPA bolster immunity among those most prone to COVID-19 including the elderly,obese,and immunocompromised patients?Does regular MVPA dampen systemic inflammation,thereby lessening the COVID-19 cytokine storm?

Novel insights in phosphodiesterase 4 subtype inhibition to target neuroinflammation and stimulate remyelination

In neurodegenerative and classically demyelinating disorders such as multiple sclerosis(MS),spinal cord injury(SCI),stroke,and Charcot-Marie-Tooth disease,glial functioning is compromised and nervous tissue integrity is lost.Recently,primary neurodegenerative disorders such as Alzheimer’s disease,amyotrophic lateral sclerosis(ALS),and Parkinson’s disease(PD)are increasingly linked to impaired oligodendroglia functioning upon neurodegeneration.Due to the destructive micro-environment created by nervous tissue damage,the progressive cellular loss in these disorders,and the amitotic nature of neurons,spontaneous endogenous repair process are limited in nature.Hence,there is a medical need for efficient therapeutic strategies capable of supporting neuro-reparative processes to occur,likely supported by improved oligodendroglia cell functioning.

Advanced brain organoids for neuroinflammation disease modeling

Brain organoids mimic closely the embryonic human brain:Over the last decade,the development of human organoid systems has evolved rapidly.Different tissues have been modeled with organoids,such as the gut,lung,liver,kidney retina and brain.These systems have a high cellular heterogeneity,with many cell types integrated into the same system.Organoids'cellular populations interact between and amongst each other in a cellular and molecular level,which represents an advantage with respects to monolayer 2D cell culture systems.

Monomeric C-reactive protein:a link between chronic inflammation and neurodegeneration?

Pre-diabetic insulin resistance is associated with sub-clinical inflammation and concomitant increase in systemic C-reactive protein(CRP)levels.Type 2 diabetes mellitus(T2DM)patients register even higher chronic levels of inflammation,with excess circulating CRP originating from both typical hepatic synthesis,and also visceral white adipose tissue.

Neuroinflammation as a therapeutic target in Huntington's disease

In 1872, George Huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. Huntington's disease(HD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

Asking one mechanism in glial cells during neuroinflammation

Multiple sclerosis(MS),which is characterized by inflammatory demyelination in the central nervous system(CNS),is the most common neurological disease in the young adult population.Experimental autoimmune encephalomyelitis(EAE),an animal model of MS,is often used in preclinical studies.Accumulating data indicate that in addition to immune cells such as T cells and dendritic cells,CNS resident microglia and astrocytes play important roles in demyelinating neuroinflammation(Healy et al.,2022).In particular,microglia are key immune-competent cells that can respond to environmental changes.Conditional depletion of transforming growth factor-β-activated kinase 1,a mitogen-associated protein kinase kinase kinase,in microglia is reported to reduce CNS inflammation and diminish axonal and myelin damage significantly.This suggests that elucidating the mechanisms of microglia-specific responses during pathologies may help in the development of treatments that reduce EAE/MS disease severity(Goldmann et al.,2013).

The miR-9-5p/CXCL11 pathway is a key target of hydrogen sulfide-mediated inhibition of neuroinflammation in hypoxic ischemic brain injury

We previously showed that hydrogen sulfide(H2S)has a neuroprotective effect in the context of hypoxic ischemic brain injury in neonatal mice.However,the precise mechanism underlying the role of H2S in this situation remains unclear.In this study,we used a neonatal mouse model of hypoxic ischemic brain injury and a lipopolysaccharide-stimulated BV2 cell model and found that treatment with L-cysteine,a H2S precursor,attenuated the cerebral infarction and cerebral atrophy induced by hypoxia and ischemia and increased the expression of miR-9-5p and cystathionineβsynthase(a major H2S synthetase in the brain)in the prefrontal cortex.We also found that an miR-9-5p inhibitor blocked the expression of cystathionineβsynthase in the prefrontal cortex in mice with brain injury caused by hypoxia and ischemia.Furthermore,miR-9-5p overexpression increased cystathionine-β-synthase and H2S expression in the injured prefrontal cortex of mice with hypoxic ischemic brain injury.L-cysteine decreased the expression of CXCL11,an miR-9-5p target gene,in the prefrontal cortex of the mouse model and in lipopolysaccharide-stimulated BV-2 cells and increased the levels of proinflammatory cytokines BNIP3,FSTL1,SOCS2 and SOCS5,while treatment with an miR-9-5p inhibitor reversed these changes.These findings suggest that H2S can reduce neuroinflammation in a neonatal mouse model of hypoxic ischemic brain injury through regulating the miR-9-5p/CXCL11 axis and restoringβ-synthase expression,thereby playing a role in reducing neuroinflammation in hypoxic ischemic brain injury.

Non-coding RNAs in exercise immunology:A systematic review

Regular physical exercise has been recognized as a potent modulator of immune function,with its effects including enhanced immune surveillance,reduced inflammation,and improved overall health.While strong evidence exists that physical exercise affects the specific expression and activity of non-coding RNAs(ncRNAs)also involved in immune system regulation,heterogeneity in individual study designs and analyzed exercise protocols exists,and a condensed list of functional,exercise-dependent ncRNAs with known targets in the immune system is missing from the literature.A systematic review and qualitative analysis was used to identify and categorize ncRNAs participating in immune modulation by physical exercise.Two combined approaches were used:(a)a systematic literature search for“ncRNA and exercise immunology”,(b)and a database search for microRNAs(miRNAs)(miRTarBase and DIANA-Tarbase v8)aligned with known target genes in the immune system based on the Reactome database,combined with a systematic literature search for“ncRNA and exercise”.Literature searches were based on PubMed,Web of Science,and SPORTDiscus;and miRNA databases were filtered for targets validated by in vitro experimental data.Studies were eligible if they reported on exercise-based interventions in healthy humans.After duplicate removal,95 studies were included reporting on 164 miRNAs,which were used for the qualitative synthesis.Six studies reporting on long-noncoding RNAs(lncRNAs)or circular RNAs were also identified.Results were analyzed using ordering tables that included exercise modality(endurance/resistance exercise),acute or chronic interventions,as well as the consistency in reported change between studies.Evaluation criteria were defined as“validated”with 100%of≥3 independent studies showing identical direction of regulation,“plausible”(≥80%),or“suggestive”(≥70%).For resistance exercise,upregulation of miR-206 was validated while downregulation of miR-133a appeared plausible.For endurance exercise,15 miRNAs were categorized as validated,with 12 miRNAs being consistently elevated and 3 miRNAs being downregulated,most of them after acute exercise training.In conclusion,our approach provides evidence that miRNAs play a major role in exercise-induced effects on the innate and adaptive immune system by targeting different pathways affecting immune cell distribution,function,and trafficking as well as production of(anti-)inflammatory cytokines.miRNAs miR-15,miR-29c,miR-30a,miR-142/3,miR-181a,and miR-338 emerged as key players in mediating the immunomodulatory effects of exercise predominantly after acute bouts of endurance exercise.

Human endogenous retrovirus type-W and multiple sclerosis–related smoldering neuroinflammation

Introduction to human endogenous retrovirus type-W(HERV-W): Genomic inheritance from the past includes retroviral sequences that have been stably incorporated into our genomes and account for up to 8% of human DNA.

Coumarin and eugenol ameliorate LPS-induced inflammation in RAW 264.7 cells via modulating the NLRP3 inflammasome pathway

Objective:To investigate the underlying mechanism of anti-inflammatory action of coumarin and eugenol in lipopolysaccharide(LPS)-stimulated RAW 264.7 cells.Methods:RAW 264.7 cells were treated with 2.5μg/mL of LPS,50μM of coumarin,and 50μM eugenol for 24 h.The viability of the cells was assessed using MTT assay.The production of nitric oxide was determined using Griess reagent and DCFH-DA was used to measure the production of reactive oxygen species.The protein expression of NLRP3,IL-1β,NF-κB,and cyclooxygenase 2 was assessed using Western blot analysis.Results:Coumarin and eugenol showed anti-inflammatory effects against LPS-induced inflammatory response by ameliorating the expression of NLRP3 inflammasome and NF-κB,which further led to a subsequent reduction in IL-1β,nitric oxide,and reactive oxygen species.Conclusions:Coumarin and eugenol exert their anti-inflammatory activities by modulating the NLRP3 inflammasome pathway and NF-κB.These compounds may have promising therapeutic applications for the treatment of various inflammatory diseases.

Benzydamine hydrochloride ameliorates ethanol-induced inflammation in RAW 264.7 macrophages by stabilizing redox homeostasis

Objective:To evaluate the protective effect of benzydamine hydrochloride against ethanol-induced oxidative stress and inflammation in RAW 264.7 macrophages.Methods:RAW 264.7 macrophages were treated with ethanol(100 mM)and benzydamine hydrochloride(7.5μM).The imflammatory status was confirmed by measuring pro-(TNF-αand IL-6)and anti-inflammatory(IL-10)cytokines through ELISA and RT-PCR assays.Reactive oxygen species generation and mitochondrial membrane potential were investigated to study the protective role of benzydamine hydrochloride against ethanol-induced oxidative stress.Apoptosis detection was also investigated using flow cytometry and acridine orange/ethidium bromide staining.Results:Benzydamine hydrochloride significantly decreased the secretion of TNF-αand IL-6,as well as the generation of reactive oxygen species inside the cells,thereby stabilizing the mitochondrial membrane potential and reducing DNA fragmentation.The ethanol-induced cellular necrosis was also reversed by the administration of benzydamine hydrochloride.Conclusions:Benzydamine hydrochloride ameliorates ethanol-induced cell apoptosis and inflammation in RAW macrophages.

Quercetin Alleviates Lipopolysaccharide-Induced Cardiac Inflammation via Inhibiting Autophagy and Programmed Cell Death

Objective The aim of this study is to explore the potential modulatory role of quercetin against Endotoxin or lipopolysaccharide(LPS)induced septic cardiac dysfunction.Methods Specific pathogen-free chicken embryos(n=120)were allocated untreated control,phosphate buffer solution(PBS)vehicle,PBS with ethanol vehicle,LPS(500 ng/egg),LPS with quercetin treatment(10,20,or 40 nmol/egg,respectively),Quercetin groups(10,20,or 40 nmol/egg).Fifteenday-old embryonated eggs were inoculated with abovementioned solutions via the allantoic cavity.At embryonic day 19,the hearts of the embryos were collected for histopathological examination,RNA extraction,real-time polymerase chain reaction,immunohistochemical investigations,and Western blotting.Results They demonstrated that the heart presented inflammatory responses after LPS induction.The LPS-induced higher mRNA expressions of inflammation-related factors(TLR4,TNFα,MYD88,NF-κB1,IFNγ,IL-1β,IL-8,IL-6,IL-10,p38,MMP3,and MMP9)were blocked by quercetin with three dosages.Quercetin significantly decreased immunopositivity to TLR4 and MMP9 in the treatment group when compared with the LPS group.Quercetin significantly decreased protein expressions of TLR4,IFNγ,MMP3,and MMP9 when compared with the LPS group.Quercetin treatment prevented LPS-induced increase in the mRNA expression of Claudin 1 and ZO-1,and significantly decreased protein expression of claudin 1 when compared with the LPS group.Quercetin significantly downregulated autophagyrelated gene expressions(PPARα,SGLT1,APOA4,AMPKα1,AMPKα2,ATG5,ATG7,Beclin-1,and LC3B)and programmed cell death(Fas,Bcl-2,CASP1,CASP12,CASP3,and RIPK1)after LPS induction.Quercetin significantly decreased immunopositivity to APOA4,AMPKα2,and LC3-II/LC3-I in the treatment group when compared with the LPS group.Quercetin significantly decreased protein expressions of AMPKα1,LC3-I,and LC3-II.Quercetin significantly decreased the protein expression to CASP1 and CASP3 by immunohistochemical investigation or Western blotting in treatment group when compared with LPS group.Conclusion Quercetin alleviates cardiac inflammation induced by LPS through modulating autophagy,programmed cell death,and myocardiocytes permeability.

Tilapia Head GlycolipidAlleviates Indomethacin-Induced Gastric Ulcer via Regulating Oxidative Stress and Inflammation Through COX/PGE2 Signaling Pathway inAdult

The aim of this experiment was to investigate the ameliorative effect and molecular mechanism of tilapia head glycolipid(TH-GL)on indomethacin(IDM)-induced gastric ulcer in male Sprague Dawley(SD)rats.The gastric ulcer model was established by oral administration of 30mgkg^(-1) IDM after 7 days of TH-GL or omeprazole(OME)administration in rats.Then the macroscopic gastric injury symptoms,gastric mucosa protective factor cyclooxygenase 1(COX-1),cyclooxygenase 2(COX-2),prostaglandin E_(2)(PGE_(2)),the levels of oxidative stress,and inflammatory cytokine expression levels in the rats were analyzed.The experimental results showed that multiple ulcers appeared on the gastric surface of the rats in the model group.Compared to the model group,TH-GL significantly alleviated gastric ulcers and reduced the gastric damage index in rats.In addition,TH-GL significantly promoted the expression of constitutive enzyme COX-1 while inhibited the expression of inducible enzyme COX-2,and make PGE2 maintain at normal levels.TH-GL also inhibited oxidative stress and inflammatory responses,increased superoxide dismutase(SOD)activity and glutathione(GSH)content,decreased the level of malondialdehyde(MDA)and the content of pro-inflammatory factor.In conclusion,these results suggested that TH-GL could maintain the expression levels of COX-1 and PGE2 while inhibit the expression of COX-2 in the gastric of rat and then prevent IDM-induced gastric ulcer,which may be related to the regulation of oxidative stress and inflammatory response.Therefore,TH-GL might be a new option for the prevention of gastric diseases induced by IDM.

Bowel function and inflammation: Is motility the other side of the coin?

Digestion and intestinal absorption allow the body to sustain itself and are the emblematic functions of the bowel.On the flip side,functions also arise from its role as an interface with the environment.Indeed,the gut houses microorganisms,collectively known as the gut microbiota,which interact with the host,and is the site of complex immune activities.Its role in human pathology is complex and scientific evidence is progressively elucidating the functions of the gut,especially regarding the pathogenesis of chronic intestinal diseases and inflammatory conditions affecting various organs and systems.This editorial aims to highlight and relate the factors involved in the pathogenesis of intestinal and systemic inflammation.

Metabolite acetyl-L-carnitine participates in Bifidobacterium animalis F1-7 to ameliorate atherosclerotic inflammation by downregulating theTLR4/NF-κB pathway

This study aimed to explore the effect of Bifidobacterium animalis F1-7 on the improvement of atherosclerotic inflammation.Arteriosclerosis model ApoE^(-/-)mice were orally administered with B.animalis F1-7 for 12 weeks.The probiotic intervention reduced the plaque areas in aorta and the accumulation of macrophages,and downregulated the expression of toll-like receptor 4(TLR4)/nuclear factorκB(NF-κB)pathway to reduce the levels of inflammatory factors.The widely-targeted metabolomics analysis showed that acetyl-L-carnitine(ALC)in the intestine of atherosclerotic mice was significantly increased after B.animalis F1-7 intervention.Correlation analysis proved that ALC was associated with atherosclerotic inflammatory response.By using oxidized low density lipoprotein induced macrophage foam cells,we further verified that ALC could reduce lipid accumulation and inflammatory response in foam cells by downregulating the TLR4/NF-κB pathway.Finally,our results revealed that B.animalis F1-7 upregulated the metabolite ALC to downregulate the inflammatory responses,leading to the reduction of plaque accumulation of atherosclerosis.

Reveal more mechanisms of precondition mesenchymal stem cells inhibiting inflammation

Hypoxia can get more ability to inhibit inflammation.But how it impact on survival time of mesenchymal stem cells(MSCs)is confusing and how preconditioned MSCs inhibiting inflammation are partially known.Those issues decided the value of preconditioned MSCs by hypoxia.

Context-dependent role of sirtuin 2 in inflammation

Sirtuin 2 is a member of the sirtuin family nicotinamide adenine dinucleotide(NAD~+)-dependent deacetylases, known for its regulatory role in different processes, including inflammation. In this context, sirtuin 2 has been involved in the modulation of key inflammatory signaling pathways and transcription factors by deacetylating specific targets, such as nuclear factor κB and nucleotide-binding oligomerization domain-leucine-rich-repeat and pyrin domain-containing protein 3(NLRP3). However, whether sirtuin 2-mediated pathways induce a pro-or an anti-inflammatory response remains controversial. Sirtuin 2 has been implicated in promoting inflammation in conditions such as asthma and neurodegenerative diseases, suggesting that its inhibition in these conditions could be a potential therapeutic strategy. Conversely, arthritis and type 2 diabetes mellitus studies suggest that sirtuin 2 is essential at the peripheral level and, thus, its inhibition in these pathologies would not be recommended. Overall, the precise role of sirtuin 2 in inflammation appears to be context-dependent, and further investigation is needed to determine the specific molecular mechanisms and downstream targets through which sirtuin 2 influences inflammatory processes in various tissues and pathological conditions. The present review explores the involvement of sirtuin 2 in the inflammation associated with different pathologies to elucidate whether its pharmacological modulation could serve as an effective strategy for treating this prevalent symptom across various diseases.

Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish

Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products.

Licorice-saponin A3 is a broad-spectrum inhibitor for COVID-19 by targeting viral spike and anti-inflammation

Currently,human health due to corona virus disease 2019(COVID-19)pandemic has been seriously threatened.The coronavirus severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spike(S)protein plays a crucial role in virus transmission and several S-based therapeutic approaches have been approved for the treatment of COVID-19.However,the efficacy is compromised by the SARS-CoV-2 evolvement and mutation.Here we report the SARS-CoV-2 S protein receptor-binding domain(RBD)inhibitor licorice-saponin A3(A3)could widely inhibit RBD of SARS-CoV-2 variants,including Beta,Delta,and Omicron BA.1,XBB and BQ1.1.Furthermore,A3 could potently inhibit SARS-CoV-2 Omicron virus in Vero E6 cells,with EC50 of 1.016μM.The mechanism was related to binding with Y453 of RBD determined by hydrogen-deuterium exchange mass spectrometry(HDX-MS)analysis combined with quantum mechanics/molecular mechanics(QM/MM)simulations.Interestingly,phosphoproteomics analysis and multi fluorescent immunohistochemistry(mIHC)respectively indicated that A3 also inhibits host inflammation by directly modulating the JNK and p38 mitogen-activated protein kinase(MAPK)pathways and rebalancing the corresponding immune dysregulation.This work supports A3 as a promising broad-spectrum small molecule drug candidate for COVID-19.