Exploring the Homeostatic and Sensory Roles of the Immune System

Decellularized Amnion Membrane Triggers Macrophage Polarization for Desired Host Immune Response

Appropriate regulation of immunomodulatory responses, particularly acute inflammation involving macrophages, is crucial for the desired functionality of implants. Decellularized amnion membrane (DAM) is produced by removing cellular components and antigenicity, expected to reduce immunogenicity and the risk of inflammation. Despite the potential of DAM as biomaterial implants, few studies have investigated its specific effects on immunomodulation. Here, it is demonstrated that DAM can regulate macrophage-driven inflammatory response and potential mechanisms are investigated. In vitro results show that DAM significantly inhibits M1 polarization in LPS-induced macrophages by inhibiting Toll-like receptors (TLR) signaling pathway and TNF signaling pathway and promotes macrophage M2 polarization. Physical signals from the 3D micro-structure and the active protein, DCN, binding to key targets may play roles in the process. In the subcutaneous implant model in rats, DAM inhibits the persistence of inflammation and fibrous capsule formation, while promoting M2 macrophage polarization, thereby facilitating tissue regeneration. This study provides insights into DAM's effect and potential mechanisms on the balance of M1/M2 macrophage polarization in vitro and vivo, emphasizing the immunomodulation of ECM-based materials as promising implants.

Current challenges in the discovery of treatments against Mayaro fever

INTRODUCTION

Mayaro fever is an emerging viral disease that manifests as an acute febrile illness. The disease is self-limiting, however joint pain can persist for months leading to chronic arthralgia. There is no specific treatment available, which ultimately leads to socioeconomic losses in populations at risk as well as strains to the public health systems.

AREAS COVERED

We reviewed the candidate treatments proposed for Mayaro virus (MAYV) infection and disease, including antiviral compounds targeting viral or host mechanisms, and pathways involved in disease development and pathogenicity. We assessed compound screening technologies and experimental infection models used in these studies and indicated the advantages and limitations of available technologies and intended therapeutic strategies.

EXPERT OPINION

Although several compounds have been suggested as candidate treatments against MAYV infection, notably those with antiviral activity, most compounds were assessed only in vitro. Compounds rarely progress toin vivo or preclinical studies, and such difficulty may be associated with limited experimental models. MAYV biology is largely inferred from related alphaviruses and reflected by few studies focusing on target proteins or mechanisms of action for MAYV. Therapeutic strategies targeting pathogenic inflammatory responses have shown potential against MAYV-induced disease in vivo, which might reduce long-term sequelae.

5-methylthiopentyl Isothiocyanate, a Sulforaphane Analogue, Inhibits Pro-inflammatory Cytokines by Regulating LPS/ATP-mediated NLRP3 Inflammasome Activation

BACKGROUND

Pro-inflammatory cytokines secreted from activated macrophages and astrocytes are crucial mediators of inflammation for host defense. Among them, the secretion of IL-1β, a major pro-inflammatory cytokine, is especially mediated by the activation of NLRP3 inflammasome. Pro-IL-1β, which is produced in response to the invaded pathogens, such as LPS, is cleaved and matured in the NLRP3 inflammasome by the recognition of ATP. Excessively activated IL-1β induces other immune cells, resulting in the up-regulation of inflammation. Therefore, regulation of NLRP3 inflammasome can be a good strategy for alleviating inflammation.

OBJECTIVE

Our study aimed to examine whether 5-methylthiopentyl isothiocyanate, a sulforaphane analogue (berteroin), has an anti-inflammatory effect on the NLRP3 inflammasome activation induced by LPS and ATP.

METHODS

Primary bone marrow-derived macrophages (BMDMs) and astrocytes were stimulated by LPS and ATP with the treatment of 5-methylthiopentyl isothiocyanate, a sulforaphane analogue. The secretion of pro-inflammatory cytokines was measured by ELISA, and the expression level of NLRP3 inflammasome-associated proteins was detected by western blot. The association of NLRP3 inflammasome was assessed by co-immunoprecipitation, and the formation of ASC specks was evaluated by fluorescent microscope.

RESULTS

5-methylthiopentyl isothiocyanate, a sulforaphane analogue (berteroin), decreased the release of pro-inflammatory cytokines, IL-1β, and IL-6 in the BMDMs. Berteroin notably prevented the formation of both NLRP3 inflammasome and ASC specks, which reduced the secretion of IL-1β. Additionally, berteroin reduced the IL-1β secretion and cleaved IL-1β expression in the primary astrocytes.

DISCUSSION AND CONCLUSION

These results indicated the anti-inflammatory effects of 5- methylthiopentyl isothiocyanate (berteroin) by regulating NLRP3 inflammasome activation, suggesting that berteroin could be the potential natural drug candidate for the regulation of inflammation.

Vital role for primary healthcare providers: urgent need to educate the community about daily nutritional self-care to support immune function and maintain health

The importance of self-care to improve health and social well-being is well recognised. Nevertheless, there remains a need to encourage people to better understand how their body works, and how to keep it healthy. Because of its important role, part of this understanding should be based on why the immune system must be supported. This highly complex system is essential for defending against pathogens, but also for maintaining health throughout the body by preserving homeostasis and integrity. Accordingly, the immune system requires active management for optimal functioning and to reduce the risk of chronic diseases. In addition to regular exercise, healthy sleeping patterns, cultivating mental resilience, adequate nutrition through healthy and diverse dietary habits is key to the daily support of immune function. Diet and the immune system are closely intertwined, and a poor diet will impair immunity and increase the risk of acute and chronic diseases. To help elucidate the roles of primary healthcare providers in supporting individuals to engage in self-care, an international group of experts reviewed the evidence for the roles of the immune system in maintaining health and for nutrition in daily immune support, and discussed implications for population health and clinical practice.

Cytokines, synaptic plasticity and network dynamics: a matter of balance

The modern view of the immune system as a sensitizing and modulating machinery of the central nervous system is now well recognized. However, the specific mechanisms underlying this fine crosstalk have yet to be fully disentangled. To control cognitive function and behavior, the two systems are engaged in a subtle interacting act. In this scenario, a dual action of pro-inflammatory cytokines in the modulation of brain network connections is emerging. Pro-inflammatory cytokines are indeed required to express physiological plasticity in the hippocampal network while being detrimental when over-expressed during uncontrolled inflammatory processes. In this dynamic equilibrium, synaptic functioning and the performance of neural networks are ensured by maintaining an appropriate balance between pro- and anti-inflammatory molecules in the central nervous system microenvironment.

Acute exercise modulates the inflammatory response in adipose tissue in both lean and obese mice

OBJECTIVES

Acute physical exercise acts as a metabolic stressor, promoting activation of the immune system, and this response could be relevant in the adipose tissue remodeling process. In addition, some cytokines have important functions in lipolysis. Because chronic exercise improves obesity-related metabolic and inflammatory dysfunction, herein we investigated the effect of acute exercise on the inflammatory responses in the adipose tissues of lean and obese mice.

METHODS

Lean mice were fed a standard chow diet, whereas obese mice were fed a high-refined carbohydrate diet for 8 wk. Both groups were subjected to 60 min of moderate-intensity exercise.

RESULTS

In the epididymal adipose tissue of lean mice, exercise enhanced interleukin (IL)-6 and tumor necrosis factor-α levels, which correlated positively with increased serum free fatty acid concentrations. In vivo confocal imaging of epididymal adipose tissue vessels revealed higher recruitment of neutrophils after exercise. Also, the number of leukocytes expressing CD11b+F480- was elevated 6 h after exercise. Similarly, the chemokine (C-X-C motif) ligand 1 level increased at 6 h and remained high until 24 h after exercise. Myeloperoxidase activity was increased at 6, 12, and 24 h after exercise. Surprisingly, however, no changes were observed in epididymal adipose tissue from obese mice, considering proinflammatory cytokines (IL-6 and tumor necrosis factor-α). On the other hand, IL-13, IL-4, and IL-10 levels were higher in obese mice after exercise.

CONCLUSIONS

These data suggest that acute exercise promotes an inflammatory response in the adipose tissue of lean mice that is observed as part of its role in adipose tissue remodeling. In contrast, acute exercise promotes an antiinflammatory response in adipose tissue from obese mice, likely as an important tool for restoring homeostasis.

Transcriptional profiling of a fungal granuloma reveals a low metabolic activity of Paracoccidioides brasiliensis yeasts and an actively regulated host immune response

Granulomas are important immunological structures in the host defense against the fungus Paracoccidioides brasiliensis, the main etiologic agent of Paracoccidioidomycosis (PCM), a granulomatous systemic mycosis endemic in Latin America. We have performed transcriptional and proteomic studies of yeasts present in the pulmonary granulomas of PCM aiming to identify relevant genes and proteins that act under stressing conditions. C57BL/6 mice were infected with 1x106 yeasts and after 8- and 12-weeks of infection, granulomatous lesions were obtained for extraction of fungal and murine RNAs and fungal proteins. Dual transcriptional profiling was done comparing lung cells and P. brasiliensis yeasts from granulomas with uninfected lung cells and the original yeast suspension used in the infection, respectively. Mouse transcripts indicated a lung malfunction, with low expression of genes related to muscle contraction and organization. In addition, an increased expression of transcripts related to the activity of neutrophils, eosinophils, macrophages, lymphocytes as well as an elevated expression of IL-1β, TNF-α, IFN-γ, IL-17 transcripts were observed. The increased expression of transcripts for CTLA-4, PD-1 and arginase-1, provided evidence of immune regulatory mechanisms within the granulomatous lesions. Also, our results indicate iron as a key element for the granuloma to function, where a high number of transcripts related to fungal siderophores for iron uptake was observed, a mechanism of fungal virulence not previously described in granulomas. Furthermore, transcriptomics and proteomics analyzes indicated a low fungal activity within the granuloma, as demonstrated by the decreased expression of genes and proteins related to energy metabolism and cell cycle.

Cross-talk between insulin resistance and nitrogen species in hypoxia leads to deterioration of tissue and homeostasis

Hypoxia has been linked with insulin resistance as it produces changes in the metabolism of the cell; in which the adipocytes impede the insulin receptor tyrosine, phosphorylation, directing at decreased levels of transport of glucose. At this juncture, we are focusing on cross-talk between insulin resistance and nitrogen species in hypoxia, leading to the deterioration of tissue and homeostasis. Physiological levels of nitric oxide play a very crucial role in acting as a priority effector and signaling molecule, arbitrating the body's responses to hypoxia. Both ROS and RNS are associated with a reduction in IRS1 phosphorylation in tyrosine, which leads to reduced levels of IRS1 content and insulin response, which further leads to insulin resistance. Cellular hypoxia is a trigger to inflammatory mediators which signal tissue impairment and initiate survival requirements. But, hypoxia-mediated inflammation act as a protective role by an immune response and promotes wound healing during infection. In this review, we abridge the crosstalk between the inflammation and highlight the dysregulation in physiological consequences due to diabetes mellitus. Finally, we review various treatments available for its related physiological complications.

Effects of fecal microbiota transplantation in metabolic syndrome: A meta-analysis of randomized controlled trials

OBJECTIVE

The prevalence of obesity and type 2 diabetes is rapidly increasing worldwide, posing serious threats to human health. This study aimed to evaluate the role of FMT in the treatment of obesity and/or metabolic syndrome and its impact on clinically important parameters.

METHODS

We searched Medline, Embase, and Cochrane Library databases up to April 31, 2022 and further assessed articles that met the eligibility criteria. Mean differences and 95% confidence intervals were used to analyze continuous data. The I2 statistic was used to measure study heterogeneity. Univariate meta-regression or subgroup analyses were performed to explore the covariates that might contribute to heterogeneity. Potential publication bias was assessed using the Egger's test. We used the GRADEpro guideline development tool to assess the quality of the evidence.

RESULTS

Nine studies, comprising 303 participants, were included in the meta-analysis. In the short-term outcomes (<6 weeks after FMT), compared with the placebo group, patients in the FMT group had lower FBG (MD = -0.12 mmol/L, 95% Cl: -0.23, -0.01), HbA1c (MD = -0.37 mmol/mol, 95%Cl: -0.73, -0.01), and insulin levels (MD = -24.77 mmol/L, 95% Cl: -37.60, -11.94), and higher HDL cholesterol levels (MD = 0.07 mmol/L, 95% Cl: 0.02, 0.11).

CONCLUSIONS

FMT, as an adjunctive therapy, does not produce any serious adverse effects and may be useful in the treatment of metabolic syndrome, especially in improving HbA1c, insulin sensitivity, and HDL cholesterol. However, there was no significant difference between the FMT group and the placebo group in terms of weight reduction.

Sciatic-Vagal Nerve Stimulation by Electroacupuncture Alleviates Inflammatory Arthritis in Lyme Disease-Susceptible C3H Mice

Lyme disease is caused by Borrelia burgdorferi, and the pathogenesis of the disease is complex with both bacterial and host factors contributing to inflammatory responses. Lyme disease affects different organs including joints and results in arthritis. Immune responses stimulated by B. burgdorferi through toll-like receptors cause infiltration of leukocytes, which produce inflammatory cytokines and facilitate spirochete clearance. However, arthritic manifestations and chronic fatigue syndrome-like symptoms persist long after completion of antibiotic treatment regimens in a significant number of patients. To counter the effects of inflammation, treatment by non-steroidal anti-inflammatory drugs, hydroxychloroquine, or synovectomy to eradicate inflammatory arthritis in the involved joint could be employed; however, they often have long-term consequences. Acupuncture has been used for a long time in Asian medicine to diminish pain during various ailments, but the effects and its mechanism are just beginning to be explored. Control of inflammation by neuronal stimulation has been exploited as a systemic therapeutic intervention to arrest inflammatory processes. Our objective was to determine whether activation of the sciatic-vagal network by electroacupuncture on ST36 acupoint, which is used to control systemic inflammation in experimental models of infectious disorders such as endotoxemia, can also alleviate Lyme arthritis symptoms in mice. This aim was further strengthened by the reports that sciatic-vagal neuronal network stimulation can lead to dopamine production in the adrenal medulla and moderate the production of inflammatory factors. We first assessed whether electroacupuncture affects spirochete colonization to attenuate Lyme arthritis. Interestingly, bioluminescent B. burgdorferi burden detected by live imaging and qPCR were similar in electroacupuncture- and mock-treated mice, while electroacupuncture induced a lasting anti-inflammatory effect on mice. Despite the discontinuation of treatment at 2 weeks, the simultaneous decrease in neutrophils in the joints and inflammatory cytokine levels throughout the body at 4 weeks suggests a systemic and persistent effect of electroacupuncture that attenuates Lyme arthritis. Our results suggest that electroacupuncture-mediated anti-inflammatory responses could offer promising healthcare benefits in patients suffering from long-term Lyme disease manifestations.

Viruses as Living Systems—A Metacybernetic View

The debate over whether viruses are living organisms tends to be paradigmatically determined. The metabolic paradigm denies that they are, while new research evidences the opposite. The purpose of this paper is to deliver a generic model for viral contexts that explains why viruses are alive. It will take a systems biology approach, with a qualitative part (using metacybernetics) to provide deeper explanations of viral contexts, and a quantitative part (using Fisher Information deriving from the variational principle of Extreme Physical Information) which is in principle able to take measurements and predict outcomes. The modelling process provides an extended view of the epigenetic processes of viruses. The generic systems biology model will depict viruses as autonomous entities with metaphysical processes of autopoietic self-organisation and adaptation, enabling them to maintain their physical viability and hence, within their populations, mutate and evolve. The autopoietic epigenetic processes are shown to describe their capability to change, and these are both qualitatively and quantitatively explored, the latter providing an approach to make measurements of physical phenomena under uncertainty. Viruses maintain their fitness when they are able to maintain their stability, and this is indicated by information flow efficacy. A brief case study is presented on the COVID-19 virus from the perspective that it is a living system, and this includes outcome predictions given Fisher Information conditions for known contexts.

Targeting CXCL12/CXCR4 Signaling with AMD3100 Might Selectively Suppress CXCR4+ T-Cell Chemotaxis Leading to the Alleviation of Chronic Prostatitis

Background

Chronic nonbacterial prostatitis (CNP) has a high incidence, low cure rate, and unclear pathogenesis. Here, we aimed to systematically identify effective diagnostic and therapeutic targets for CNP.

Methods

Prostate tissues were obtained from established mouse models and negative controls and were used for mRNA array sequencing and immunohistochemistry (IHC) staining. Predominant pathways were identified based on pathway enrichment analysis and pharmaceutical experiments. We also investigated the functional role of CXCL12 on CP, a critical factor belonging to the predominant chemotaxis pathway, and employed IHC staining to explore the influence of the CXCL12/CXCR4 axis on the activation of the NF-κB, AKT, and STAT3 signaling pathways. Serum samples derived from both CNP cases and healthy controls were used to determine the secretion level of CXCL12.

Results

By employing mRNA array sequencing and immunohistochemistry, we found that CXCR4, CXCL12, CD44, and OFLM4 were highly expressed in the infiltrated inflammatory T cells of the prostate tissues generated from CNP mice, while they were rarely expressed on the epithelial cells. Based on the pathway enrichment results, we applied pathway inhibitors to suppress the activity of these classic pathways. We found that targeting the CXCL12/CXCR4 axis with its specific antagonist AMD3100 remarkably alleviated inflammatory infiltration of the prostate in CNP models. Similar results were obtained when we replaced AMD3100 with adenovirus-associated virus (AAV)-shCxcl12. To clarify the potential mechanisms of how the CXCL12/CXCR4 axis influences the pathogenesis of CNP, we tested the classical downstream pathways. The results suggested that p-Akt, p-STAT3, and p-NF-κB were more highly expressed on the inflammatory cells of the prostate derived from the CNP model and were partly suppressed after applying AMD3100 or delivering AAV-shCxcl12, indicating that the CXCL12/CXCR4 axis potentially functioned through AKT/NF-κB and STAT3 signaling to influence the pathogenesis of CNP.

Conclusion

Our study provides potential diagnostic biomarkers and therapeutic targets for CNP.

Modulatory effects of R10 fraction of garlic (Allium sativum L.) on hormonal levels, T cell polarization, and fertility-related genes in mice model of polycystic ovarian syndrome

Polycystic ovary syndrome (PCOS) is an inflammatory endocrine-metabolic disorder related to reproductive system characterized by polycystic ovarian morphology, androgen excess, and chronic anovulation. Current treatments haven't been very successful in PCOS treatment and the problem still remains as a challenge. Therefore, new approaches should be applied to overcome the disease. Previous studies demonstrated immunomodulatory effects of R10 fraction of garlic in the treatment of inflammatory conditions such as cancer. Considering previous studies suggesting immunomodulatory therapy for PCOS, therapeutic effects of R10 fraction was evaluated in a mouse model of PCOS. To do so, PCOS was developed by intramuscular injection of estradiol valerate. Treatment with R10 fraction, isolated from garlic, was performed and the alterations in hormonal levels (estradiol, progesterone, and testosterone), T cell polarization markers (IFN-γ, IL-4, and IL-17), and expression of fertility-related genes (Gpx3 and Ptx3) were evaluated. The results showed that hormonal levels were elevated in PCOS model comparing to normal animals but were markedly modulated after treatment with R10 fraction. Moreover, a severe disturbance in T cell polarization with a significant reduction of fertility-related genes expression were detected in PCOS-induced ovaries. Treatment with R10 fraction also represented modulatory effects on T cell polarization by increasing IL-4 and decreasing IL-17 and IFN-γ levels. Accordingly, fertility-related genes were also modulated following treatment with R10 fraction in PCOS. Our study elucidated that R10 fraction of garlic possess immunomodulatory effects alleviating PCOS symptoms. This approach could be adjusted to give rise the optimum therapeutic results and considered as a candidate therapeutic approach for PCOS.

Adaptive homeostasis and the p53 isoform network

All living organisms have developed processes to sense and address environmental changes to maintain a stable internal state (homeostasis). When activated, the p53 tumour suppressor maintains cell and organ integrity and functions in response to homeostasis disruptors (stresses) such as infection, metabolic alterations and cellular damage. Thus, p53 plays a fundamental physiological role in maintaining organismal homeostasis. The TP53 gene encodes a network of proteins (p53 isoforms) with similar and distinct biochemical functions. The p53 network carries out multiple biological activities enabling cooperation between individual cells required for long‐term survival of multicellular organisms (animals) in response to an ever‐changing environment caused by mutation, infection, metabolic alteration or damage. In this review, we suggest that the p53 network has evolved as an adaptive response to pathogen infections and other environmental selection pressures.

Anti-Inflammatory Effects of Huberia peruviana Cogn. Methanol Extract by Inhibiting Src Activity in the NF-κB Pathway

There is a growing need to develop anti-inflammatory drugs to regulate inflammatory responses. An extract of Huberia peruviana Cogn. had the best inhibitory effect on nitric oxide (NO) production in screening process undertaken in our laboratory. However, the anti-inflammatory effect of Huberia peruviana Cogn. methanol extract (Hp-ME) has not been studied. In this study, the anti-inflammatory effect of Hp-ME was assessed by using an NO assay, RT-PCR, luciferase reporter gene activity assay, western blotting assay, HCl/EtOH-induced acute gastritis model, and LPS-induced acute lung injury model. The phytochemical components of Hp-ME were determined through LC-MS/MS analysis. When RAW264.7 and HEK293T cells were treated with Hp-ME, NO production was decreased dose-dependently without cytotoxicity and the mRNA levels of iNOS, COX-2, and TNF-α were decreased. In a luciferase assay, the activity of transcription factors, NF-κB in TRIF or MyD88-overexpressing HEK293T cells was extremely reduced by Hp-ME. The western blotting analysis indicated that Hp-ME has anti-inflammatory effects by inhibiting the phosphorylation of Src. Hp-ME showed anti-inflammatory effects on in vivo models of HCl/EtOH-induced gastritis and LPS-induced acute lung injury. LC-MS/MS revealed that Hp-ME contains several anti-inflammatory flavonoids. The final findings of this study imply that Hp-ME could be used as an anti-inflammatory drug in several inflammatory diseases.

The Immunity Clock

The immune system has been for long considered a marker of health. The age-related decline in its function results in a greater incidence of infections, autoimmune diseases and cancer. Nevertheless, it is still not known if immune function can be used to accurately estimate the rate of aging of an individual. A set of 14 immune function variables were measured in 214 healthy individuals ranging from 19 to 88 years old. All immune variables were selected as independent variables for the prediction of age by multiple linear regression (MLR). The Immunity Clock was constructed including the following 5 immune variables: natural killer activity, phagocytosis and chemotaxis of neutrophils and chemotaxis and proliferative capacity of lymphocytes reaching an adjusted R 2 of 80.3% and a standard error of the estimate of 4.74 years. The Immunity Clock was validated in a different group of healthy individuals (N=106) obtaining a Pearson´s correlation coefficient of 0.898 (p < 0.001) between chronological age and the age estimated by the Immunity Clock, the ImmunolAge. Moreover, we demonstrate that women with anxiety (N=10) show a higher ImmunolAge than their chronological age whereas healthy centenarians (N=8) show a lower one. In addition, the Immunity Clock provided here proves to be useful for monitoring the effectiveness of a nutritional intervention lasting one month, by detecting a diminished ImmunolAge in the same individuals. Further research will be needed to ascertain if the Immunity Clock is a passive marker of the aging process or it plays an active role in it.

Aerobic Training Modulates the Increase in Plasma Concentrations of Cytokines in response to a Session of Exercise

Acute physical exercise can modulate immune function. For example, acute exercise is known to increase the circulating concentration of cytokines. Exercise is also known to modulate immune function chronically. It is not known whether exercise training can result in training of the immune system. Here, we investigated the effects of six weeks of aerobic training on cytokine responses induced by acute exercise until fatigue. Twelve healthy men performed a fatiguing exercise at the anaerobic threshold (AT) intensity. After the training period, the participants performed another bout of acute exercise at the same duration and intensity of the pretraining situation. The analysis was made at the beginning, end, and at 10, 30, and 60 minutes during the recovery period. Training at AT induced a gain of 11.2% of exercise capacity. Before training, a single bout of acute exercise induced a significant increase in plasma levels of cytokines, including IL-6, TNF-α, sTNFR1, IL-10, CXCL10, BDNF, leptin, resistin, and adiponectin. After six weeks of aerobic training, levels of IL-6, sTNFR1, BDNF, and leptin increased to a lesser extent after an acute bout exercise at the same absolute intensity as the pretraining period. Responses to the same relative exercise intensity were similar to those observed before exercise. These results show that aerobic training is associated with training of acute immune responses to acute exercise until fatigue.

Recent Advances in Antiinflammatory Material Design

Implants and prostheses are widely used to replace damaged tissues or to treat various diseases. However, besides the risk of bacterial or fungal infection, an inflammatory response usually occurs. Here, recent progress in the field of anti-inflammatory biomaterials is described. Different materials and approaches are used to decrease the inflammatory response, including hydrogels, nanoparticles, implant surface coating by polymers, and a variety of systems for anti-inflammatory drug delivery. Complex multifunctional systems dealing with inflammation, microbial infection, bone regeneration, or angiogenesis are also described. New promising stimuli-responsive systems, such as pH- and temperature-responsive materials, are also being developed that would enable an "intelligent" antiinflammatory response when the inflammation occurs. Together, different approaches hold promise for creation of novel multifunctional smart materials allowing better implant integration and tissue regeneration.

Severe COVID-19: understanding the role of immunity, endothelium, and coagulation in clinical practice

SARS-CoV-2 is responsible for the COVID-19 pandemic. The immune system is a determinant factor in defense against viral infections. Thus, when it acts in a balanced and effective manner the disease is self-limited and benign. Nevertheless, in a significant proportion of the population, the immune response is exaggerated. When infected, patients with diabetes, hypertension, obesity, and cardiovascular disease are more likely to progress to severe forms. These diseases are related to chronic inflammation and endothelial dysfunction. Toll-like receptors are expressed on immune cells and play an important role in the physiopathology of cardiovascular and metabolic diseases. When activated, they can induce release of inflammatory cytokines. Hypercoagulability, hyperinflammation, platelet hyperresponsiveness, and endothelial dysfunction occur in immune system hyperactivity caused by viral activity, thereby increasing the risk of arterial and venous thrombosis. We discuss the interactions between COVID-19, immunity, the endothelium, and coagulation, as well as why cardiometabolic diseases have a negative impact on COVID-19 prognosis.

Vascular Endothelial Cells and Innate Immunity

In addition to the roles of endothelial cells (ECs) in physiological processes, ECs actively participate in both innate and adaptive immune responses. We previously reported that, in comparison to macrophages, a prototypic innate immune cell type, ECs have many innate immune functions that macrophages carry out, including cytokine secretion, phagocytic function, antigen presentation, pathogen-associated molecular patterns-, and danger-associated molecular patterns-sensing, proinflammatory, immune-enhancing, anti-inflammatory, immunosuppression, migration, heterogeneity, and plasticity. In this highlight, we introduce recent advances published in both ATVB and many other journals: (1) several significant characters classify ECs as novel immune cells not only in infections and allograft transplantation but also in metabolic diseases; (2) several new receptor systems including conditional danger-associated molecular pattern receptors, nonpattern receptors, and homeostasis associated molecular patterns receptors contribute to innate immune functions of ECs; (3) immunometabolism and innate immune memory determine the innate immune functions of ECs; (4) a great induction of the immune checkpoint receptors in ECs during inflammations suggests the immune tolerogenic functions of ECs; and (5) association of immune checkpoint inhibitors with cardiovascular adverse events and cardio-oncology indicates the potential contributions of ECs as innate immune cells.

MicroRNA expression profile in chronic nonbacterial prostatitis revealed by next-generation small RNA sequencing

MicroRNAs (miRNAs) are considered to be involved in the pathogenic initiation and progression of chronic nonbacterial prostatitis (CNP); however, the comprehensive expression profile of dysregulated miRNAs, relevant signaling pathways, and core machineries in CNP have not been fully elucidated. In the current research, CNP rat models were established through the intraprostatic injection of carrageenan into the prostate. Then, next-generation sequencing was performed to explore the miRNA expression profile in CNP. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) bioinformatical analyses were conducted to reveal the enriched biological processes, molecular functions, and cellular components and signaling pathways. As a result, 1224, 1039, and 1029 known miRNAs were annotated in prostate tissues from the blank control (BC), normal saline injection (NS), and carrageenan injection (CAR) groups (n = 3 for each group), respectively. Among them, 84 miRNAs (CAR vs BC) and 70 miRNAs (CAR vs NS) with significantly different expression levels were identified. Compared with previously reported miRNAs with altered expression in various inflammatory diseases, the majority of deregulated miRNAs in CNP, such as miR-146b-5p, miR-155-5p, miR-150-5p, and miR-139-5p, showed similar expression patterns. Moreover, bioinformatics analyses have enriched mitogen-activated protein kinase (MAPK), cyclic adenosine monophosphate (cAMP), endocytosis, mammalian target of rapamycin (mTOR), and forkhead box O (FoxO) signaling pathways. These pathways were all involved in immune response, which indicates the critical regulatory role of the immune system in CNP initiation and progression. Our investigation has presented a global view of the differentially expressed miRNAs and potential regulatory networks containing their target genes, which may be helpful for identifying the novel mechanisms of miRNAs in immune regulation and effective target-specific theragnosis for CNP.

Donor metabolic characteristics drive effects of faecal microbiota transplantation on recipient insulin sensitivity, energy expenditure and intestinal transit time

OBJECTIVE

Bariatric surgery improves glucose metabolism. Recent data suggest that faecal microbiota transplantation (FMT) using faeces from postbariatric surgery diet-induced obese mice in germ-free mice improves glucose metabolism and intestinal homeostasis. We here investigated whether allogenic FMT using faeces from post-Roux-en-Y gastric bypass donors (RYGB-D) compared with using faeces from metabolic syndrome donors (METS-D) has short-term effects on glucose metabolism, intestinal transit time and adipose tissue inflammation in treatment-naïve, obese, insulin-resistant male subjects.

DESIGN

Subjects with metabolic syndrome (n=22) received allogenic FMT either from RYGB-D or METS-D. Hepatic and peripheral insulin sensitivity as well as lipolysis were measured at baseline and 2 weeks after FMT by hyperinsulinaemic euglycaemic stable isotope (²H₂-glucose and ²H₅-glycerol) clamp. Secondary outcome parameters were changes in resting energy expenditure, intestinal transit time, faecal short-chain fatty acids (SCFA) and bile acids, and inflammatory markers in subcutaneous adipose tissue related to intestinal microbiota composition. Faecal SCFA, bile acids, glycaemic control and inflammatory parameters were also evaluated at 8 weeks.

RESULTS

We observed a significant decrease in insulin sensitivity 2 weeks after allogenic METS-D FMT (median rate of glucose disappearance: from 40.6 to 34.0 µmol/kg/min; p<0.01). Moreover, a trend (p=0.052) towards faster intestinal transit time following RYGB-D FMT was seen. Finally, we observed changes in faecal bile acids (increased lithocholic, deoxycholic and (iso)lithocholic acid after METS-D FMT), inflammatory markers (decreased adipose tissue chemokine ligand 2 (CCL2) gene expression and plasma CCL2 after RYGB-D FMT) and changes in several intestinal microbiota taxa.

CONCLUSION

Allogenic FMT using METS-D decreases insulin sensitivity in metabolic syndrome recipients when compared with using post-RYGB-D. Further research is needed to delineate the role of donor characteristics in FMT efficacy in human insulin-resistant subjects.

TRIAL REGISTRATION NUMBER

NTR4327.

Biochemical study on occupational inhalation of benzene vapours in petrol station

inhalation of benzene vapours promote various and dangerous health problems. Fuel station workers are most susceptible to benzene inhalation toxicity. Samples were collected twice, at beginning of the study and 6 months later from 40 fuel station workers from different egyptian governorates and 10 control healthy volunteers. Fuel station workers were sub divided into four groups according to years working in the station. All of them are exposed to benzene vapours and exhausts during their duties, their work shifts were 8 hrs./day. Results indicated that; benzene vapours exposure induced significant increasing in serum Lead and Cadmium and Myeloperoxidase (MPO) enzyme activity levels. This goes with marked immunologic changes presented by decreases in immunoglobulins; IgA and IgG, along with increases in levels of IgM and IgE. Also, Malondialdehyde (MDA) levels were significantly increased. Meanwhile, reduction in some other biochemical parameters including; Copper, Zinc and Iron micronutrients, as well as; Superoxide Dismutase (SOD), Catalase (CAT) enzyme levels and Glutathione (GSH) content. Hence, the study inferred that prolonged benzene inhalation can lead to biochemical and immune disorders, probably through potentiating oxidative stress and inflammation pathways.

Biomimetic Tissue Engineering: Tuning the Immune and Inflammatory Response to Implantable Biomaterials

Regenerative medicine technologies rely heavily on the use of well-designed biomaterials for therapeutic applications. The success of implantable biomaterials hinges upon the ability of the chosen biomaterial to negotiate with the biological barriers in vivo. The most significant of these barriers is the immune system, which is composed of a highly coordinated organization of cells that induce an inflammatory response to the implanted biomaterial. Biomimetic platforms have emerged as novel strategies that aim to use the principle of biomimicry as a means of immunomodulation. This principle has manifested itself in the form of biomimetic scaffolds that imitate the composition and structure of biological cells and tissues. Recent work in this area has demonstrated the promising potential these technologies hold in overcoming the barrier of the immune system and, thereby, improve their overall therapeutic efficacy. In this review, a broad overview of the use of these strategies across several diseases and future avenues of research utilizing these platforms is provided.

Neuroimmune Activation Drives Multiple Brain States

Neuroimmune signaling is increasingly identified as a critical component of neuronal processes underlying memory, emotion and cognition. The interactions of microglia and astrocytes with neurons and synapses, and the individual cytokines and immune signaling molecules that mediate these interactions are a current focus of much research. Here, we discuss neuroimmune activation as a mechanism triggering different states that modulate cognitive and affective processes to allow for appropriate behavior during and after illness or injury. We propose that these states lie on a continuum from a naïve homeostatic baseline state in the absence of stimulation, to acute neuroimmune activity and chronic activation. Importantly, consequences of illness or injury including cognitive deficits and mood impairments can persist long after resolution of immune signaling. This suggests that neuroimmune activation also results in an enduring shift in the homeostatic baseline state with long lasting consequences for neural function and behavior. Such different states can be identified in a multidimensional way, using patterns of cytokine and glial activation, behavioral and cognitive changes, and epigenetic signatures. Identifying distinct neuroimmune states and their consequences for neural function will provide a framework for predicting vulnerability to disorders of memory, cognition and emotion both during and long after recovery from illness.

Evaluating Causality of Gut Microbiota in Obesity and Diabetes in Humans

The pathophysiology of obesity and obesity-related diseases such as type 2 diabetes mellitus (T2DM) is complex and driven by many factors. One of the most recently identified factors in development of these metabolic pathologies is the gut microbiota. The introduction of affordable, high-throughput sequencing technologies has substantially expanded our understanding of the role of the gut microbiome in modulation of host metabolism and (cardio)metabolic disease development. Nevertheless, evidence for a role of the gut microbiome as a causal, driving factor in disease development mainly originates from studies in mouse models: data showing causality in humans are scarce. In this review, we will discuss the quality of evidence supporting a causal role for the gut microbiome in the development of obesity and diabetes, in particular T2DM, in humans. Considering overlap in potential mechanisms, the role of the gut microbiome in type 1 diabetes mellitus will also be addressed. We will elaborate on factors that drive microbiome composition in humans and discuss how alterations in microbial composition or microbial metabolite production contribute to disease development. Challenging aspects in determining causality in humans will be postulated together with strategies that might hold potential to overcome these challenges. Furthermore, we will discuss means to modify gut microbiome composition in humans to help establish causality and discuss systems biology approaches that might hold the key to unravelling the role of the gut microbiome in obesity and T2DM.

Improvement of Insulin Sensitivity after Lean Donor Feces in Metabolic Syndrome Is Driven by Baseline Intestinal Microbiota Composition

The intestinal microbiota has been implicated in insulin resistance, although evidence regarding causality in humans is scarce. We therefore studied the effect of lean donor (allogenic) versus own (autologous) fecal microbiota transplantation (FMT) to male recipients with the metabolic syndrome. Whereas we did not observe metabolic changes at 18 weeks after FMT, insulin sensitivity at 6 weeks after allogenic FMT was significantly improved, accompanied by altered microbiota composition. We also observed changes in plasma metabolites such as γ-aminobutyric acid and show that metabolic response upon allogenic FMT (defined as improved insulin sensitivity 6 weeks after FMT) is dependent on decreased fecal microbial diversity at baseline. In conclusion, the beneficial effects of lean donor FMT on glucose metabolism are associated with changes in intestinal microbiota and plasma metabolites and can be predicted based on baseline fecal microbiota composition.

When less means more: dehydration improves innate immunity in rattlesnakes

Immune function can vary based on availability of resources, and most studies of such influences have focused on the co-investment of energy into immune and other physiological functions. When energy resources are limited, trade-offs exist, which can compromise immunity for other functions. As with energy, water limitation can also alter various physiological processes, yet water has received little consideration for its role in possibly modulating immune functions. We examined the relationship between immunocompetence and hydration state using the western diamond-backed rattlesnake (Crotalus atrox). This species is known to undergo substantial seasonal fluctuations in water availability with extreme limitations during the hot, dry season. We collected blood samples from free-ranging C. atrox to compare osmolality and innate immune function (lysis, agglutination, bacterial growth inhibition) during the milder and relatively moister early spring season, the hot-dry season, and the hot-wet season. To isolate effects of dehydration from other possible seasonal influences, we complemented this field study with a laboratory study in which we withheld food and water from individually housed adult C. atrox for up to 16 weeks. We collected blood samples from each snake as it dehydrated and collected a final sample after the snake was given ad lib water at the end of the experiment. Our results demonstrate that C. atrox experience significant dehydration during the hot-dry season, and that, in general, innate immune function is highly correlated with osmolality, whether natural or artificially manipulated.