The polarization of T(h)1/T(h)2 balance is dependent on the intracellular thiol redox status of macrophages due to the distinctive cytokine production

The Role of Glutathione in Selected Viral Diseases

During inflammatory processes, immunocompetent cells are exposed to substantial amounts of free radicals and toxic compounds. Glutathione is a cysteine-containing tripeptide that is an important and ubiquitous antioxidant molecule produced in human organs. The intracellular content of GSH regulates the detoxifying capacity of cells, as well as the inflammatory and immune response. GSH is particularly important in the liver, where it serves as the major non-protein thiol involved in cellular antioxidant defense. There are numerous causes of hepatitis. The inflammation of the liver can be caused by a variety of infectious viruses. The relationship between oxidative stress and the hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis E virus (HEV) infection is not fully known. The aim of this study was to examine the relationship between hepatotropic viruses and glutathione status, including reduced glutathione (GSH) and oxidized glutathione (GSSG), as well as antioxidant enzymes, e.g., glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) in liver diseases.

NRF2 Mediates Cellular Resistance to Transformation, Radiation, and Inflammation in Mice

Nuclear factor erythroid 2-related factor 2 (NRF2) is recognized as a master transcription factor that regulates expression of numerous detoxifying and antioxidant cytoprotective genes. In fact, models of NRF2 deficiency indicate roles not only in redox regulation, but also in metabolism, inflammatory/autoimmune disease, cancer, and radioresistancy. Since ionizing radiation (IR) generates reactive oxygen species (ROS), it is not surprising it activates NRF2 pathways. However, unexpectedly, activation is often delayed for many days after the initial ROS burst. Here, we demonstrate that, as assayed by γ-H2AX staining, rapid DNA double strand break (DSB) formation by IR in primary mouse Nrf2-/- MEFs was not affected by loss of NRF2, and neither was DSB repair to any great extent. In spite of this, basal and IR-induced transformation was greatly enhanced, suggesting that NRF2 protects against late IR-induced genomic instability, at least in murine MEFs. Another possible IR- and NRF2-related event that could be altered is inflammation and NRF2 deficiency increased IR-induced NF-κB pro-inflammatory responses mostly late after exposure. The proclivity of NRF2 to restrain inflammation is also reflected in the reprogramming of tumor antigen-specific lymphocyte responses in mice where Nrf2 k.o. switches Th2 responses to Th1 polarity. Delayed NRF2 responses to IR may be critical for the immune transition from prooxidant inflammation to antioxidant healing as well as in driving cellular radioresistance and survival. Targeting NRF2 to reprogram immunity could be of considerable therapeutic benefit in radiation and immunotherapy.

The Good and the Bad: Monocytes' and Macrophages' Diverse Functions in Inflammation

Monocytes and macrophages are central players of the innate immune response and play a pivotal role in the regulation of inflammation. Thereby, they actively participate in all phases of the immune response, from initiating inflammation and triggering the adaptive immune response, through to the clearance of cell debris and resolution of inflammation. In this review, we described the mechanisms of monocyte and macrophage adaptation to rapidly changing microenvironmental conditions and discussed different forms of macrophage polarization depending on the environmental cues or pathophysiological condition. Therefore, special focus was placed on the tight regulation of the pro- and anti-inflammatory immune response, and the diverse functions of S100A8/S100A9 proteins and the scavenger receptor CD163 were highlighted, respectively. We paid special attention to the function of pro- and anti-inflammatory macrophages under pathological conditions.

The Role of Reactive Oxygen Species in the Rheumatoid Arthritis-Associated Synovial Microenvironment

Rheumatoid arthritis (RA) is an inflammatory disease that begins with a loss of tolerance to modified self-antigens and immune system abnormalities, eventually leading to synovitis and bone and cartilage degradation. Reactive oxygen species (ROS) are commonly used as destructive or modifying agents of cellular components or they act as signaling molecules in the immune system. During the development of RA, a hypoxic and inflammatory situation in the synovium maintains ROS generation, which can be sustained by increased DNA damage and malfunctioning mitochondria in a feedback loop. Oxidative stress caused by abundant ROS production has also been shown to be associated with synovitis in RA. The goal of this review is to examine the functions of ROS and related molecular mechanisms in diverse cells in the synovial microenvironment of RA. The strategies relying on regulating ROS to treat RA are also reviewed.

Perioperative Administration of Cystine and Theanine Suppresses Inflammation and Facilitates Early Rehabilitation and Recovery after Esophagectomy: A Randomized, Double-Blind, Controlled Clinical Trial

Oral administration of cystine and theanine (CT) increases glutathione levels to modulate the inflammatory response, which has yet to be sufficiently explored for patients’ recovery and early rehabilitation. We planned a randomized, double-blind, placebo-controlled trial to determine whether perioperative oral administration of CT promotes recovery after esophagectomy. Patients were randomized into either CT or placebo groups, who received preoperative and postoperative treatments for 4 and 13 days, respectively. The main outcome measures were triaxial accelerometer readings, inflammation indicators, a 6 min walk test (6MWT), and a quality of life questionnaire (QoR-40). The study involved 32 patients. Although the CT group (n = 16) showed better patient activity across the investigated period, there was no significant difference between the two groups. However, white blood cell count on postoperative days (POD) 2 and 10, neutrophil count (POD 2, 7, and 10), and C-reactive protein level (POD 13) in the CT group were significantly lower than in the placebo group. Furthermore, 6MWT on POD 7 and QoR-40 on POD 13 were significantly higher in the CT group than those in the placebo group. This study suggests that perioperative administration of CT may contribute to early recovery and rehabilitation after esophagectomy via suppression of inflammatory response.

Obesity and Maternal-Placental-Fetal Immunology and Health

Obesity rates in women of childbearing age is now at 29%, according to recent CDC reports. It is known that obesity is associated with oxidative stress and inflammation, including disruptions in cellular function and cytokine levels. In pregnant women who are obese, associated placental dysfunction can lead to small for gestational age (SGA) infants. More frequently, however, maternal obesity is associated with large for gestational age (LGA) newborns, who also have higher incidence of metabolic disease and asthma due to elevated levels of inflammation. In addition, anthropogenic environmental exposures to "endocrine disrupting" and "forever" chemicals affect obesity, as well as maternal physiology, the placenta, and fetal development. Placental function is intimately associated with the control of inflammation during pregnancy. There is a large amount of literature examining the relationship of placental immunology, both cellular and humoral, with pregnancy and neonatal outcomes. Cells such as placental macrophages and NK cells have been implicated in spontaneous miscarriage, preeclampsia, preterm birth, perinatal neuroinflammation, and other post-natal conditions. Differing levels of placental cytokines and molecular inflammatory mediators also have known associations with preeclampsia and developmental outcomes. In this review, we will specifically examine the literature regarding maternal, placental, and fetal immunology and how it is altered by maternal obesity and environmental chemicals. We will additionally describe the relationship between placental immune function and clinical outcomes, including neonatal conditions, autoimmune disease, allergies, immunodeficiency, metabolic and endocrine conditions, neurodevelopment, and psychiatric disorders.

GPI-80 Augments NF-κB Activation in Tumor Cells

Recent studies have discovered a relationship between glycosylphosphatidylinositol (GPI)-anchored protein 80 (GPI-80)/VNN2 (80 kDa GPI-anchored protein) and malignant tumors. GPI-80 is known to regulate neutrophil adhesion; however, the action of GPI-80 on tumors is still obscure. In this study, although the expression of GPI-80 mRNA was detectable in several tumor cell lines, the levels of GPI-80 protein were significantly lower than that in neutrophils. To clarify the function of GPI-80 in tumor cells, GPI-80-expressing cells and GPI-80/VNN2 gene-deleted cells were established using PC3 prostate cancer cells. In GPI-80-expressing cells, GPI-80 was mainly detected in vesicles. Furthermore, soluble GPI-80 in the conditioned medium was associated with the exosome marker CD63 and was also detected in the plasma obtained from prostate cancer patients. Unexpectedly, cell adhesion and migration of GPI-80-expressing PC3 cells were not modulated by anti-GPI-80 antibody treatment. However, similar to the GPI-80 family molecule, VNN1, the pantetheinase activity and oxidative state were augmented in GPI-80-expressing cells. GPI-80-expressing cells facilitated non-adhesive proliferation, slow cell proliferation, NF-κB activation and IL-1β production. These phenomena are known to be induced by physiological elevation of the oxidative state. Thus, these observations indicated that GPI-80 affects various tumor responses related to oxidation.

Treatment failure to sodium stibogluconate in cutaneous leishmaniasis: A challenge to infection control and disease elimination

The first-line treatment for Leishmania donovani-induced cutaneous leishmaniasis (CL) in Sri Lanka is intra-lesional sodium stibogluconate (IL-SSG). Antimony failures in leishmaniasis is a challenge both at regional and global level, threatening the ongoing disease control efforts. There is a dearth of information on treatment failures to routine therapy in Sri Lanka, which hinders policy changes in therapeutics. Laboratory-confirmed CL patients (n = 201) who attended the District General Hospital Hambantota and Base Hospital Tangalle in southern Sri Lanka between 2016 and 2018 were included in a descriptive cohort study and followed up for three months to assess the treatment response of their lesions to IL-SSG. Treatment failure (TF) of total study population was 75.1% and the majority of them were >20 years (127/151,84%). Highest TF was seen in lesions on the trunk (16/18, 89%) while those on head and neck showed the least (31/44, 70%). Nodules were least responsive to therapy (27/31, 87.1%) unlike papules (28/44, 63.6%). Susceptibility to antimony therapy seemed age-dependant with treatment failure associated with factors such as time elapsed since onset to seeking treatment, number and site of the lesions. This is the first detailed study on characteristics of CL treatment failures in Sri Lanka. The findings highlight the need for in depth investigations on pathogenesis of TF and importance of reviewing existing treatment protocols to introduce more effective strategies. Such interventions would enable containment of the rapid spread of L.donovani infections in Sri Lanka that threatens the ongoing regional elimination drive.

Quercetin-Loaded Ceria Nanocomposite Potentiate Dual-Directional Immunoregulation via Macrophage Polarization against Periodontal Inflammation

Macrophage polarization toward M1 phenotype (pro-inflammation) is closely associated with the destructive phase of periodontal inflammation. Nanoceria is verified to inhibit M1 polarization of macrophages by the favorable ability of reactive oxygen species (ROS) scavenging. However, the function of nanoceria on macrophage polarization toward M2 phenotype (anti-inflammation) in reparative phase of periodontal inflammation is quite limited. In this work, by introducing an antioxidant drug quercetin onto nano-octahedral ceria, synergistic and intense regulation of host immunity against periodontal disease is realized. Such nanocomposite can control the phenotypic switch of macrophages by not only inhibition of M1 polarization for suppressing the damage in the destructive phase but also promotion of M2 polarization for regenerating the surrounding tissues in reparative phase of periodontal disease. As-prepared nanocomposite can effectively increase the M2/M1 ratio of macrophage polarization in inflammatory cellular models by lipopolysaccharide stimulation. More importantly, the nanocomposite also exerts an improved therapeutic potential against local inflammation by significant downregulation of pro-inflammatory cytokines and upregulation of anti-inflammatory cytokines in an animal model with periodontal inflammation. Therefore, this newly developed nanomedicine is efficient in ROS scavenging and driving pro-inflammatory macrophages to the anti-inflammatory phenotype to eliminate inflammation, thereby providing a promising candidate for treating periodontal inflammation.

The Effects of Maternal Smoking on Pregnancy and Offspring: Possible Role for EGF?

Cigarette smoke exposure during pregnancy and lactation is associated with adverse pregnancy outcomes. Here, we investigated the effects of maternal smoke exposure on pregnancy and offspring immunity and explored whether, epidermal growth factor (EGF), an important growth-promoting factor in human colostrum and milk, might be a possible missing link in maternal smoke exposure and changes in infants’ immune responses. Pregnant BALB/c mice were exposed to either cigarette smoke or air during gestation and lactation, and effects on pulmonary inflammation in dams and immune responses in offspring were examined. Maternal smoke exposure increased airway hyperresponsiveness and accumulation of inflammatory cells in the lungs of pregnant dams compared to non-pregnant dams. The E-cadherin protein expression was reduced in mammary glands of cigarette smoke-exposed pregnant dams. EGF levels were higher in mammary glands and serum of smoke-exposed pregnant dams compared to air-exposed pregnant dams. Offspring from cigarette smoke-exposed dams exhibited elevated levels of IL-17A, MCP-1, IL-22, and IL-13 in anti-CD3 stimulated spleen cell culture supernatants. EGF levels were also increased in serum of offspring from smoke-exposed dams. A positive correlation was observed between serum EGF levels and neutrophil numbers in bronchoalveolar lavage fluid of the dams. Interestingly, IL-17A, MCP-1, IL-22, IL13, and IFN-γ levels in anti-CD3 stimulated spleen cell culture supernatants of male pups also showed a positive correlation with EGF serum levels. In summary, our results reveal that maternal smoke exposure predisposes dams to exacerbated airway inflammation and offspring to exacerbated immune responses and both phenomena are associated with elevated EGF concentrations.

Redox interactions of immune cells and muscle in the regulation of exercise-induced pain and analgesia: implications on the modulation of muscle nociceptor sensory neurons

The mechanistic interactions among redox status of leukocytes, muscle, and exercise in pain regulation are still poorly understood and limit targeted treatment. Exercise benefits are numerous, including the treatment of chronic pain. However, unaccustomed exercise may be reported as undesirable as it may contribute to pain. The aim of the present review is to evaluate the relationship between oxidative metabolism and acute exercise-induced pain, and as to whether improved antioxidant capacity underpins the analgesic effects of regular exercise. Preclinical and clinical studies addressing relevant topics on mechanisms by which exercise modulates the nociceptive activity and how redox status can outline pain and analgesia are discussed, in sense of translating into refined outcomes. Emerging evidence points to the role of oxidative stress-induced signaling in sensitizing nociceptor sensory neurons. In response to acute exercise, there is an increase in oxidative metabolism, and consequently, pain. Instead, regular exercise can modulate redox status in favor of antioxidant capacity and repair mechanisms, which have consequently increased resistance to oxidative stress, damage, and pain. Data indicate that acute sessions of unaccustomed prolonged and/or intense exercise increase oxidative metabolism and regulate exercise-induced pain in the post-exercise recovery period. Further, evidence demonstrates regular exercise improves antioxidant status, indicating its therapeutic utility for chronic pain disorders. An improved comprehension of the role of redox status in exercise can provide helpful insights into immune-muscle communication during pain modulatory effects of exercise and support new therapeutic efforts and rationale for the promotion of exercise.

Macrophage Related Chronic Inflammation in Non-Healing Wounds

Persistent hyper-inflammation is a distinguishing pathophysiological characteristic of chronic wounds, and macrophage malfunction is considered as a major contributor thereof. In this review, we describe the origin and heterogeneity of macrophages during wound healing, and compare macrophage function in healing and non-healing wounds. We consider extrinsic and intrinsic factors driving wound macrophage dysregulation, and review systemic and topical therapeutic approaches for the restoration of macrophage response. Multidimensional analysis is highlighted through the integration of various high-throughput technologies, used to assess the diversity and activation states as well as cellular communication of macrophages in healing and non-healing wound. This research fills the gaps in current literature and provides the promising therapeutic interventions for chronic wounds.

CTLA-2 Alpha Is a Potent Inhibitor of Angiogenesis in Murine Ocular Tissue

Cytotoxic T lymphocyte antigen-2 (CTLA-2) alpha has been reported to suppress the activities of cathepsin L (Cath L), which is deeply involved in angiogenesis. Therefore, we assessed whether CTLA-2 alpha plays a role in angiogenesis in ocular tissue. To establish models of corneal inflammation and experimental choroidal neovascularization (CNV), male C57BL/6J mice (n = 5) underwent corneal suture placement or laser-induced CNV, respectively. Mice were then injected with recombinant CTLA-2 alpha (1 µg) into the peritoneal cavity at day 0 and every 2 days after operation. In vitro experiments were performed to assess the inflammatory response by measuring TNF-alpha secretion in peritoneal cavity exudate cells (PECs) or the proliferation of mouse vascular endothelial cells (mVECs). CTLA-2 alpha treatment dramatically suppressed corneal angiogenesis, as well as laser-induced CNV. Moreover, CTLA-2 alpha inhibited the proliferation of mVECs in vitro, while CTLA-2 alpha abolishment was able to rescue proliferation. However, CTLA-2 alpha could not suppress cytokine secretion from inflammatory cells such as PECs. In summary, CTLA-2 alpha was able to suppress angiogenesis by suppressing endothelial cell proliferation. Further studies are needed to investigate its usefulness as a new antiangiogenic treatment for a variety of conditions, including age-related macular degeneration.

Keratinocytes-Derived Reactive Oxygen Species Play an Active Role to Induce Type 2 Inflammation of the Skin: A Pathogenic Role of Reactive Oxygen Species at the Early Phase of Atopic Dermatitis

Background

Atopic dermatitis (AD) is characterized by chronic, relapsing skin inflammation (eczema) with itchy sensation. Keratinocytes, which are located at the outermost part of our body, are supposed to play important roles at the early phase of type 2 inflammation including AD pathogenesis.

Objective

The purpose of this study was to evaluate whether keratinocytes-derived reactive oxygen species (ROS) could be produced by the allergens or non-allergens, and the keratinocytes-derived ROS could modulate a set of biomarkers for type 2 inflammation of the skin.

Methods

Normal human epidermal keratinocytes (NHEKs) were treated with an allergen of house dust mites (HDM) or a non-allergen of compound 48/80 (C48/80). Then, biomarkers for type 2 inflammation of the skin including those for neurogenic inflammation were checked by reverse transcriptase-polymerase chain reaction and western immunoblot experiments.

Results

HDM or C48/80 was found to upregulate expression levels of our tested biomarkers, including type 2 T helper-driving pathway (KLK5, PAR2, and NFκB), epithelial-cell-derived cytokines (thymic stromal lymphopoietin, interleukin [IL]-25, IL-33), and neurogenic inflammation (NGF, CGRP). The HDM- or C-48/80-induced expression levels of the biomarkers could be blocked by an antioxidant treatment with 5 mM N-acetyl-cysteine. In contrast, pro-oxidant treatment with 1 mM H₂O₂ could upregulate expression levels of the tested biomarkers in NHEKs.

Conclusion

Our results reveal that keratinocytes-derived ROS, irrespective to their origins from allergens or non-allergens, have a potential to induce type 2 inflammation of AD skin.

An Overview of Nrf2 Signaling Pathway and Its Role in Inflammation

Inflammation is a key driver in many pathological conditions such as allergy, cancer, Alzheimer’s disease, and many others, and the current state of available drugs prompted researchers to explore new therapeutic targets. In this context, accumulating evidence indicates that the transcription factor Nrf2 plays a pivotal role controlling the expression of antioxidant genes that ultimately exert anti-inflammatory functions. Nrf2 and its principal negative regulator, the E3 ligase adaptor Kelch-like ECH- associated protein 1 (Keap1), play a central role in the maintenance of intracellular redox homeostasis and regulation of inflammation. Interestingly, Nrf2 is proved to contribute to the regulation of the heme oxygenase-1 (HO-1) axis, which is a potent anti-inflammatory target. Recent studies showed a connection between the Nrf2/antioxidant response element (ARE) system and the expression of inflammatory mediators, NF-κB pathway and macrophage metabolism. This suggests a new strategy for designing chemical agents as modulators of Nrf2 dependent pathways to target the immune response. Therefore, the present review will examine the relationship between Nrf2 signaling and the inflammation as well as possible approaches for the therapeutic modulation of this pathway.

Altered redox regulation and S-glutathionylation of BiP contribute to bortezomib resistance in multiple myeloma

Multiple myeloma (MM) cells have high rates of secretion of proteins rich in disulfide bonds and depend upon compartmentalized redox balance for accurate protein folding. The proteasome inhibitor bortezomib (Btz) is a successful frontline treatment for the disease, but its long-term efficacy is restricted by the acquisition of resistance. We found that MM cell lines resistant to Btz maintain high levels of oxidative stress and are cross resistant to endoplasmic reticulum (ER) stress-inducing agents thapsigargin (ThG), and tunicamycin (TuM). Moreover, cells expressing high/wild type levels of glutathione S-transferase P (GSTP) are more resistant than Gstp1/p2 knockout cells. In agreement, basal levels of S-glutathionylated proteins and redox regulation enzymes, including GSTP are elevated at mRNA and protein levels in resistant cells. GSTP mediated S-glutathionylation (SSG) regulates the activities of a number of redox active ER proteins. Here we demonstrated that the post-translational modification determines the balance between foldase and ATPase activities of the binding immunoglobulin protein (BiP), with Cys41-SSG important for ATPase, and Cys420-SSG for foldase. BiP expression and S-glutathionylation are increased in clinical specimens of bone marrow from MM patients compared to non-cancerous samples. Preventing S-glutathionylation in MM cells with a GSTP specific inhibitor restored BiP activities and reversed resistance to Btz. Therefore, S-glutathionylation of BiP confers pro-survival advantages and represents a novel mechanism of drug resistance in MM cells. We conclude that altered GSTP expression leads to S-glutathionylation of BiP, and contributes to acquired resistance to Btz in MM.

Redox-Modulating Agents in the Treatment of Viral Infections

Viruses use cell machinery to replicate their genome and produce viral proteins. For this reason, several intracellular factors, including the redox state, might directly or indirectly affect the progression and outcome of viral infection. In physiological conditions, the redox balance between oxidant and antioxidant species is maintained by enzymatic and non-enzymatic systems, and it finely regulates several cell functions. Different viruses break this equilibrium and induce an oxidative stress that in turn facilitates specific steps of the virus lifecycle and activates an inflammatory response. In this context, many studies highlighted the importance of redox-sensitive pathways as novel cell-based targets for therapies aimed at blocking both viral replication and virus-induced inflammation. In the review, we discuss the most recent findings in this field. In particular, we describe the effects of natural or synthetic redox-modulating molecules in inhibiting DNA or RNA virus replication as well as inflammatory pathways. The importance of the antioxidant transcription factor Nrf2 is also discussed. Most of the data reported here are on influenza virus infection. We believe that this approach could be usefully applied to fight other acute respiratory viral infections characterized by a strong inflammatory response, like COVID-19.

Modulatory Effects of Pb2+ on Virally Challenged Chicken Macrophage (HD-11) and B-Lymphocyte (DT40) Cell Lines In Vitro

Elevated levels of lead have been found in waterfowl, due to human activities. Lead may cause immunomodulatory effects, but the mechanisms are largely unknown, especially after viral challenges. To characterize avian immunomodulatory hazards of lead (Pb)2+ , we used chicken macrophage (HD-11) and B-lymphocyte (DT40) cell lines, as in vitro models for the innate and adaptive immune systems, respectively. The cells were activated via toll-like receptor-3 by polyinosinic-polycytidylic acid sodium salt (poly I:C), mimicking viral infections. Our results indicate that Pb2+ is cytotoxic to both cell lines, macrophages being more sensitive. De novo synthesis of glutathione plays an important role in protecting macrophages from Pb2+ intoxication, which might also be closely involved in the induction of nitric oxide after Pb2+ exposure. Stimulatory effects on cell proliferation were noticed at noncytotoxic Pb2+ concentrations as well. Exposure to Pb2+ could also affect the inflammatory status by inhibiting the pro-inflammatory interferon (IFN)-γ while promoting the production of anti-inflammatory type I IFNs in both macrophages and B-cells, and increasing intracellular IgM levels in B-cells. These results suggest that the immunomodulatory effects of Pb2+ in birds are probably closely associated with disruption of immune cell proliferation and cytokine production, potentially causing disorders of the avian immune system. Environ Toxicol Chem 2020;39:1060-1070. © 2020 SETAC.

Chemical individuality in T cells: A Garrodian view of immunometabolism

Metabolically quiescent T cells circulate throughout the body in search of antigen. Following engagement of their cognate receptors, T cells undergo metabolic reprogramming to support their activation, differentiation, and ultimately function. In the spirit of Sir Archibald Garrod, this metabolic reprogramming actually imparts a chemical individuality which confers advantage, while in others confers vulnerability, depending upon the milieu. Studying T cell immunometabolism in the context of inborn errors of metabolism allows one to define essential pathways of intermediary metabolism as well metabolic vulnerabilities and plasticity. Inborn errors of metabolism, a class of diseases first named by Garrod, have a long history of being informative for common physiologic and pathologic processes. This endeavor may be accomplished through the study of patients, animal models, and in vitro models of inborn errors of metabolism. In this review, the basics of intermediary metabolism and core metabolic pathways will be discussed, along with their relationship to T cell immunometabolism. Due to their pleiotropic nature, the reader will be specifically directed toward various inborn errors of metabolism which may be helpful for answering important questions about the role of metabolism in T cells.

Antioxidant defense in the eyes of immunocompetent and immunosuppressed mice infected with Acanthamoeba spp

Background

Acanthamoeba spp. are ubiquitous pathogens which cause granulomatous amoebic encephalitis and disseminated infection. Moreover, Acanthamoeba spp. infection of the cornea leads to Acanthamoeba keratitis. Our previous study showed that the infection of an eyeball may also take place via the migration of trophozoites through the optic nerve from the brain to the eyes. The aim of the study was to analyze the activity of enzymatic antioxidants and the concentration of non-enzymatic antioxidant in the eyes of immunocompetent and immunocompromised mice with disseminated acanthamoebiasis.

Results

In the immunocompetent mice infected with Acanthamoeba spp. we noted a significant decrease in catalase activity at 8 and 16 days post-infection (dpi). Glutathione reductase activity was significantly lower at 16 dpi compared to the control group and glutathione concentration was statistically higher at 24 dpi than in the control group. In the immunosuppressed mice, a statistically significant increase in glutathione concentration in the eye samples was found at 16 dpi compared to those not infected with Acanthamoeba spp. In the immunosuppressed mice infected with Acanthamoeba spp., glutathione peroxidase activity was statistically lower at 8 dpi, and glutathione concentration was statistically significantly higher at 16 dpi compared to the control group.

Conclusions

The inflammatory response in the eyes of hosts with experimental acanthamoebiasis led to changes in the activity of enzymatic antioxidants and the content of non-enzymatic antioxidant. Therefore, the dysregulation of antioxidants may play a role in the pathomechanism of Acanthamoeba eye infection.

Scavenging reactive oxygen species selectively inhibits M2 macrophage polarization and their pro-tumorigenic function in part, via Stat3 suppression

Tumor associated macrophages (TAM) enhance the aggressiveness of breast cancer via promoting cancer cell growth, metastasis, and suppression of the patient's immune system. These TAMs are polarized in breast cancer with features more closely resembling the pro-tumorigenic and immunosuppressive M2 type rather than the anti-tumor and pro-inflammatory M1 type. The goal of our study was to examine primary human monocyte-derived M1 and M2 macrophages for key redox differences and determine sensitivities of these macrophages to the redox-active drug, MnTE-2-PyP⁵⁺. This compound reduced levels of M2 markers and inhibited their ability to promote cancer cell growth and suppress T cell activation. The surface levels of the T cell suppressing molecule, PD-L2, were reduced by MnTE-2-PyP⁵⁺ in a dose-dependent manner. This study also examined key differences in ROS generation and scavenging between M1 and M2 macrophages. Our results indicate that M2 macrophages have lower levels of reactive oxygen species (ROS) and lower production of extracellular hydrogen peroxide compared to the M1 macrophages. These differences are due in part to reduced expression levels of pro-oxidants, Nox2, Nox5, and the non-enzymatic members of the Nox complex, p22phox and p47phox, as well as higher levels of antioxidant enzymes, Cu/ZnSOD, Gpx1, and catalase. More importantly, we found that despite having lower ROS levels, M2 macrophages require ROS for proper polarization, as addition of hydrogen peroxide increased M2 markers. These TAM-like macrophages are also more sensitive to the ROS modulator and a pan-Nox inhibitor. Both MnTE-2-PyP⁵⁺ and DPI inhibited expression levels of M2 marker genes. We have further shown that this inhibition was partly mediated through a decrease in Stat3 activation during IL4-induced M2 polarization. Overall, this study reveals key redox differences between M1 and M2 primary human macrophages and that redox-active drugs can be used to inhibit the pro-tumor and immunosuppressive phenotype of TAM-like M2 macrophages. This study also provides rationale for combining MnTE-2-PyP⁵⁺ with immunotherapies.

Interleukin 10, lipid profile, vitamin D, selenium, metabolic syndrome, and serum antioxidant capacity in elderly people with and without cardiovascular disease: Amirkola health and ageing project cohort-based study

BACKGROUND

The age-related autoinflammation-mediated atherosclerosis is associated with some immunological, nutritional, and metabolic parameters and redox status. Here, we evaluated the association of circulatory interleukin 10 (IL-10) levels with lipid profile, some nutrients, and total anti-oxidant capacity in elderly people who presented cardiovascular disease (CVD) with or without metabolic syndrome (MetS) and in healthy subjects.

METHODS

In this cross-sectional case-control study, 258 sera prepared from elderly people (144 healthy and 114 patient subjects) who participated in a community-based study, the Amirkola Health and Ageing Project (AHAP), were analyzed for IL-10, lipid profile, vitamin D, selenium (Se), antioxidant capacity, and MetS.

RESULTS

Compared to patients, the healthy subjects exhibited higher levels of circulatory IL-10 among individuals with detectable serum IL-10 (P = 0.036). However, this difference was not observed when total subjects from both groups were compared, since more than 90% of those people were IL-10-negative. Se, vitamin D, and antioxidant levels were similar in both groups. There was a negative association between IL-10 and body mass index (BMI) (P < 0.050) and an equivocal association with vitamin D levels, whereas the association between IL-10 and other indicated variables was not significant. Significant association was observed between MetS and CVD prevalence (P < 0.001). There was a positive correlation between Se and total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) (P < 0.010) in healthy subjects and with TC in patients (P < 0.050).

CONCLUSION

A major proportion of elderly people were serum IL-10-negative, whereas independently to IL-10, MetS was most common in patients with CVD. Weight loss may have the potential to increase IL-10 levels in the elderly.

Glutathione Induced Immune-Stimulatory Activity by Promoting M1-Like Macrophages Polarization via Potential ROS Scavenging Capacity

The present study investigated the immunomodulatory activity of reduced glutathione (GSH) by assessment of the macrophage polarization (MP)-mediated immune response in RAW 264.7 cells. Furthermore, we identified the signal pathway associated with immune regulation by GSH. The expressions of MP-associated cytokines and chemokines were assessed using cytokine array, nCounter Sprit platform, ELISA and immunoblotting. Phagocytosis activity and intracellular reactive oxygen species (ROS) generation were measured using fluorescence-activated cell sorter. As results of the cytokine array and nCounter gene array, GSH not only up-regulated pro-inflammatory cytokines, including interleukins and tumor necrosis factor-α, but also overexpressed neutrophil-attracting chemokines. Furthermore, GSH significantly stimulated the production of immune mediators, including nitric oxide and PGE₂, as well as phagocytosis activity through nuclear factor kappa B activation. In addition, GSH significantly decreased LPS-induced ROS generation, which was associated with an activation of nuclear factor erythroid-derived 2-related factor 2 (Nrf2)/ heme oxygenease-1 (HO-1) signaling pathway. Our results suggest that GSH has potential ROS scavenging capacity via the induction of Nrf2-mediated HO-1, and immune-enhancing activity by regulation of M1-like macrophage polarization, indicating that GSH may be a useful strategy to increase the human defense system.

Selenium deficiency inhibits differentiation and immune function and imbalances the Th1/Th2 of dendritic cells

Selenium (Se) deficiency inhibits immune cell differentiation, affects immune response, and leads to cellular and humoral immune dysfunction. However, the impact of Se deficiency on the differentiation and Th1/Th2 balance of dendritic cells is still unclear. In this study, we replicated a model of Se-deficient chickens by feeding the chickens with a low-Se diet (i.e., the content of Se is 0.008 mg per kg diet). On this basis, we explored the effect of Se deficiency on the differentiation of chicken dendritic cells by induction culture of peripheral blood monocyte cells. We induced chicken dendritic cells by incubating mononuclear cells with a 100 ng mL-1 recombinant chicken granulocyte-macrophage colony-stimulating factor and 20 ng mL-1 recombinant chicken IL-4 for total 7 days. The results showed that Se deficiency decreased the expression of cell-surface markers including CD11c, CD40, CD86, and MHC II. Furthermore, we analyzed the cytokine profiles using real-time quantitative PCR and ELISA. The results indicated that Se deficiency inhibited the expression of selenoproteins and changed the secretion of IL-10, IL-12p40, and IFN-γ. Additionally, Se deficiency weakened the ability of dendritic cells to stimulate the proliferation of mixed allogeneic lymphocytes. In conclusion, Se deficiency suppressed the differentiation and immune function of chicken dendritic cells by down-regulating the expression of CD11c, CD40, CD86, MHC II, and selenoproteins. The result also showed that the Th1/Th2 imbalance was induced by enhancing the secretion of Th1-type cytokine IL-12p40 and IFN-γ and reducing that of Th2-type cytokine IL-10. Our findings contribute to understanding the mechanism of Se deficiency in the differentiation and immune function of chicken dendritic cells.

GSH-C4 Acts as Anti-inflammatory Drug in Different Models of Canonical and Cell Autonomous Inflammation Through NFκB Inhibition

An imbalance in GSH/GSSG ratio represents a triggering event in pro-inflammatory cytokine production and inflammatory response. However, the molecular mechanism(s) through which GSH regulates macrophage and cell autonomous inflammation remains not deeply understood. Here, we investigated the effects of a derivative of GSH, the N-butanoyl glutathione (GSH-C4), a cell permeable compound, on lipopolisaccharide (LPS)-stimulated murine RAW 264.7 macrophages, and human macrophages. LPS alone induces a significant production of pro-inflammatory cytokines, such as IL-1β, IL-6, and TNF-α and a significant decrement of GSH content. Such events were significantly abrogated by treatment with GSH-C4. Moreover, GSH-C4 was highly efficient in buffering cell autonomous inflammatory status of aged C2C12 myotubes and 3T3-L1 adipocytes by suppressing the production of pro-inflammatory cytokines. We found that inflammation was paralleled by a strong induction of the phosphorylated form of NFκB, which translocates into the nucleus; a process that was also efficiently inhibited by the treatment with GSH-C4. Overall, the evidence suggests that GSH decrement is required for efficient activation of an inflammatory condition and, at the same time, GSH-C4 can be envisaged as a good candidate to abrogate such process, expanding the anti-inflammatory role of this molecule in chronic inflammatory states.

Immunomodulatory Effect of Lentinan on Aberrant T Subsets and Cytokines Profile in Non-small Cell Lung Cancer Patients

As a purified active component from traditional Chinese medicine, lentinan administration can be applied as beneficial chemo-immunotherapy for anti-tumor. In this study, the immunomodulatory effects of lentinan on aberrant T subsets and cytokines profile were evaluated for non-small cell lung cancer (NSCLC). Of all NSCLC patients treated with NP chemotherapeutic protocol (combination of vinorelbin and cisplatin), 73 cases were recruited in this retrospective cohort trial study, of which 38 cases received additional lentinan. The changes of aberrant T subsets and cytokines profile were compared between two groups (chemotherapy in combination with lentinan vs. conserved single chemotherapy) by flow cytometry and molecular biology. Higher subset ratio of CD3⁺CD8⁺ cytotoxic T cells was confirmed in the peripheral blood of NSCLC patients. Chemo-immunotherapy of lentinan resulted in a significant increase of CD3 + CD56+ NKT cells (15.7 ± 3.1%), compared with 8.6 ± 1.4% of NKT cells in single chemotherapy group, and up-regulated CD3⁺CD8⁺ and CD3⁺CD4⁺ subsets as well, but caused the decrease of CD4⁺CD25⁺ Tregs induction, accompanied by significant alleviation of IL-10 and TGF-β1, and elevation of IFN-γ, TNF-α, and IL-12 (P < 0.05). It could be confirmed that lentinan could not only enhance the cellular immunity and promote the beneficial of anti-tumor by associated immunotherapy, but also had the ability to inhibit the expansion of immune suppressive Tregs in the NSCLC patients, in whom there was a raised Tregs induction compared to health control. Lentinan-based chemo-immunotherapy is a promising strategy for anti-tumor via enhancing the proliferation of cytotoxic T cells, followed by the elevation of inflammatory chemokines/cytokines. Meanwhile, the percentage of CD4+ CD25+ Tregs is down-regulated, leading to a shift in the inflammatory status from Th2 to Th1 in NSCLC patients treated with lentinan.

Tobacco Smoke Induces and Alters Immune Responses in the Lung Triggering Inflammation, Allergy, Asthma and Other Lung Diseases: A Mechanistic Review

Many studies have been undertaken to reveal how tobacco smoke skews immune responses contributing to the development of chronic obstructive pulmonary disease (COPD) and other lung diseases. Recently, environmental tobacco smoke (ETS) has been linked with asthma and allergic diseases in children. This review presents the most actual knowledge on exact molecular mechanisms responsible for the skewed inflammatory profile that aggravates inflammation, promotes infections, induces tissue damage, and may promote the development of allergy in individuals exposed to ETS. We demonstrate how the imbalance between oxidants and antioxidants resulting from exposure to tobacco smoke leads to oxidative stress, increased mucosal inflammation, and increased expression of inflammatory cytokines (such as interleukin (IL)-8, IL-6 and tumor necrosis factor α ([TNF]-α). Direct cellular effects of ETS on epithelial cells results in increased permeability, mucus overproduction, impaired mucociliary clearance, increased release of proinflammatory cytokines and chemokines, enhanced recruitment of macrophages and neutrophils and disturbed lymphocyte balance towards Th2. The plethora of presented phenomena fully justifies a restrictive policy aiming at limiting the domestic and public exposure to ETS.

Effect of yeast (Xanthophyllomyces dendrorhous) and plant (Saint John's wort, lemon balm, and rosemary) extract based functional diets on antioxidant and immune status of Atlantic salmon (Salmo salar) subjected to crowding stress

Salmon farming may face stress due to the intensive culture conditions with negative impacts on overall performance. In this aspect, functional feed improves not only the basic nutritional requirements but also the health status and fish growth. However, to date no studies have been carried out to evaluate the effect of functional diets in salmon subjected to crowding stress. Thus, the aim of this study was to evaluate the effect of yeast extract (Xanthophyllomyces dendrorhous; diet A) and the combination of plant extracts (common Saint John's wort, lemon balm, and rosemary; diet B) on the antioxidant and immune status of Atlantic salmon grown under normal cultured conditions and then subjected to crowding stress. Fish were fed with functional diets during 30 days (12 kg/m³) and then subjected to crowding stress (20 kg/m³) for 10 days. The lipid peroxidation in gut showed that both diets induced a marked decrease on oxidative damage when fish were subjected to crowding stress. The protein carbonylation in muscle displayed at day 30 a marked decrease in both functional diets that was more marked on the stress condition. The expression of immune markers (IFNγ, CD4, IL-10, TGF-β, IgM_mb, IgM_sec, T-Bet, and GATA-3) indicated the upregulation of those associated to humoral-like response (CD4, IL-10, GATA-3) when fish were subjected to crowding stress. These results were confirmed with the expression of secreted IgM. Altogether, these functional diets improved the antioxidant status and increased the expression of genes related to Th2-like response suggesting a protective role on fish subjected to crowding stress.

S-Glutathionylation of estrogen receptor α affects dendritic cell function

Glutathione S-transferase Pi (GSTP) is a thiolase that catalyzes the addition of glutathione (GSH) to receptive cysteines in target proteins, producing an S-glutathionylated residue. Accordingly, previous studies have reported that S-glutathionylation is constitutively decreased in cells from mice lacking GSTP (Gstp1/p2^-/-). Here, we found that bone marrow-derived dendritic cells (BMDDCs) from Gstp1/p2^-/- mice have proliferation rates that are greater than those in their WT counterparts (Gstp1/p2^+/+). Moreover, Gstp1/p2^-/- BMDDCs had increased reactive oxygen species (ROS) levels and decreased GSH:glutathione disulfide (GSSG) ratios. Estrogen receptor α (ERα) is linked to myeloproliferation and differentiation, and we observed that its steady-state levels are elevated in Gstp1/p2^-/- BMDDCs, indicating a link between GSTP and ERα activities. BMDDCs differentiated by granulocyte-macrophage colony-stimulating factor had elevated ERα levels, which were more pronounced in Gstp1/p2^-/- than WT mice. When stimulated with lipopolysaccharide for maturation, Gstp1/p2^-/- BMDDCs exhibited augmented endocytosis, maturation rate, cytokine secretion, and T-cell activation; heightened glucose uptake and glycolysis; increased Akt signaling (in the mTOR pathway); and decreased AMPK-mediated phosphorylation of proteins. Of note, GSTP formed a complex with ERα, stimulating ERα S-glutathionylation at cysteines 221, 245, 417, and 447; altering ERα's binding affinity for estradiol; and reducing overall binding potential (receptor density and affinity) 3-fold. Moreover, in Gstp1/p2^-/- BMDDCs, ERα S-glutathionylation was constitutively decreased. Taken together, these findings suggest that GSTP-mediated S-glutathionylation of ERα controls BMDDC differentiation and affects metabolic function in dendritic cells.

Redox-Dependent Inflammation in Islet Transplantation Rejection

Type 1 diabetes is an autoimmune disease that results in the progressive destruction of insulin-producing pancreatic β-cells inside the islets of Langerhans. The loss of this vital population leaves patients with a lifelong dependency on exogenous insulin and puts them at risk for life-threatening complications. One method being investigated to help restore insulin independence in these patients is islet cell transplantation. However, challenges associated with transplant rejection and islet viability have prevented long-term β-cell function. Redox signaling and the production of reactive oxygen species (ROS) by recipient immune cells and transplanted islets themselves are key players in graft rejection. Therefore, dissipation of ROS generation is a viable intervention that can protect transplanted islets from immune-mediated destruction. Here, we will discuss the newly appreciated role of redox signaling and ROS synthesis during graft rejection as well as new strategies being tested for their efficacy in redox modulation during islet cell transplantation.

Macrophages: Their role, activation and polarization in pulmonary diseases

Macrophages, circulating in the blood or concatenated into different organs and tissues constitute the first barrier against any disease. They are foremost controllers of both innate and acquired immunity, healthy tissue homeostasis, vasculogenesis and congenital metabolism. Two hallmarks of macrophages are diversity and plasticity due to which they acquire a wobbling array of phenotypes. These phenotypes are appropriately synchronized responses to a variety of different stimuli from either the tissue microenvironment or - microbes or their products. Based on the phenotype, macrophages are classified into classically activated/(M1) and alternatively activated/(M2) which are further sub-categorized into M2a, M2b, M2c and M2d based upon gene expression profiles. Macrophage phenotype metamorphosis is the regulating factor in initiation, progression, and termination of numerous inflammatory diseases. Several transcriptional factors and other factors controlling gene expression such as miRNAs contribute to the transformation of macrophages at different points in different diseases. Understanding the mechanisms of macrophage polarization and modulation of their phenotypes to adjust to the micro environmental conditions might provide us a great prospective for designing novel therapeutic strategy. In view of the above, this review summarises the activation of macrophages, the factors intricated in activation along with benefaction of macrophage polarization in response to microbial infections, pulmonary toxicity, lung injury and other inflammatory diseases such as chronic obstructive pulmonary dysplasia (COPD), bronchopulmonary dysplasia (BPD), asthma and sepsis, along with the existing efforts to develop therapies targeting this facet of macrophage biology.

Ameliorative effects of Artemisia pallens in a murine model of ovalbumin-induced allergic asthma via modulation of biochemical perturbations

INTRODUCTION

Asthma is a chronic, heterogeneous airway disorder characterized by airway inflammatory and remodeling. Artemisia pallens has been reported to possess antioxidant, anti-inflammatory and Anti-allergic potential.

OBJECTIVE

To evaluate the anti-asthmatic effects of methanolic extract of Artemisia pallens (APME) against ovalbumin (OVA)-induced airway hyperresponsiveness (AHR) in rats.

MATERIALS AND METHOD

AHR was induced in male Sprague-Dawley rats (180-200g) by intraperitoneal (i.p.) injection of OVA and boosted with an identical OVA solution (s.c.) on day 7. Rats were either treated orally with vehicle (10mg/kg), montelukast (10mg/kg) or APME (100, 200 and 400mg/kg) for next 28days. At the end treatments, various biochemical, molecular (RT-PCR and ELISA analysis) and histological parameters were evaluated.

RESULTS

APME (200 and 400mg/kg) significantly attenuated (p<0.05) OVA-induced alteration in lung functions measured by Whole-body plethysmography. Increased Bronchoalveolar Lavage (BAL) fluid differential cell count, as well as total protein and albumin in BAL fluid and lungs, was significantly decreased (p<0.05) by APME. It also significantly attenuated (p<0.05) elevated lung oxido-nitrosative stress, myeloperoxidase, and serum IgE levels. OVA-induced down-regulation in lung Nrf2 and upregulation in TNF-α, IL-1β, IL-4, IL-6, TGF-β mRNA expression was significantly attenuated (p<0.05) by APME (200 and 400mg/kg) treatment. Histopathological analysis of lung tissue showed that APME treatment reduced OVA-induced inflammatory influx and fibrosis.

CONCLUSION

Artemisia pallens simultaneously orchestrate plethora of mechanisms viz. modulations of IgE, TGF-β, TNF-α, IL's and Nrf-2 levels to exhibit its anti-asthmatic potential in OVA-induced AHR in rats.

Anti-stress effect of the Lactobacillus pentosus strain S-PT84 in mice

We investigated if the orally administered Lactobacillus pentosus strain S-PT84 (S-PT84) might show anti-stress activity and ameliorate stress-induced immune suppression in mice. Stress of mice induced an increase in serum corticosterone and a decrease in splenic natural killer activity and in the number of splenocytes versus control mice. However, these changes were not observed in stressed mice that had been administered S-PT84. Furthermore, interleukin (IL)-12 and IL-10 production, which was downregulated in lipopolysaccharide-activated macrophages from stressed mice, was maintained at control levels in the macrophages of stressed mice that had been fed S-PT84. Interferon-γ production, which was downregulated in concanavalin A-activated splenocytes from stressed mice, tended to be maintained at control levels in stressed mice that had been fed S-PT84, although IL-4 production by these cells was not influenced by S-PT84 administration. Additionally, reduced glutathione (GSH) levels were decreased in serum and peritoneal macrophages from stressed mice versus controls, but these GSH levels were significantly higher in stressed animals that had been administered S-PT84 compared with those that had not. These results suggest that S-PT84 exerts anti-stress activity through immune modulation and/or antioxidative activity.

Cu,Zn-Superoxide Dismutase-Mediated Redox Regulation of Jumonji Domain Containing 3 Modulates Macrophage Polarization and Pulmonary Fibrosis

M2 macrophages are implicated in the development of pulmonary fibrosis as they generate profibrotic signals. The polarization process, at least in part, is regulated by epigenetic modulation. Because Cu,Zn-superoxide dismutase-induced H2O2 can polarize macrophages to a profibrotic M2 phenotype, we hypothesized that modulation of the redox state of the cell is involved in the epigenetic modulation of the macrophage phenotype. In this study, we show that signal transducer and activator of transcription 6 (STAT6) regulates Jumonji domain containing (Jmjd) 3, a histone H3 lysine 27 demethylase, and mutation of a redox-sensitive cysteine in STAT6 attenuates jmjd3 expression. Moreover, Jmjd3 deficiency abrogates profibrotic M2 gene expression. Treatment with leflunomide, which reduces mitochondrial reactive oxygen species production and tyrosine phosphorylation, inhibits jmjd3 expression and M2 polarization, as well as development of a fibrotic phenotype. Taken together, these observations provide evidence that the redox regulation of Jmjd3 is a unique regulatory mechanism for Cu,Zn-superoxide dismutase-mediated profibrotic M2 polarization. Furthermore, leflunomide, which reduces reactive oxygen species production and tyrosine phosphorylation, may prove to be therapeutic in the treatment of asbestos-induced pulmonary fibrosis.

Role of ATP as a Key Signaling Molecule Mediating Radiation-Induced Biological Effects

Adenosine triphosphate (ATP) serves as a signaling molecule for adaptive responses to a variety of cytotoxic agents and plays an important role in mediating the radiation stress-induced responses that serve to mitigate or repair the injurious effects of γ radiation on the body. Indeed, low doses of radiation may have a net beneficial effect by activating a variety of protective mechanisms, including antitumor immune responses. On the other hand, ATP signaling may be involved in the radiation resistance of cancer cells. Here, focusing on our previous work, we review the evidence that low-dose γ irradiation (0.25-0.5 Gy) induces release of extracellular ATP, and that the released ATP mediates multiple radiation-induced responses, including increased intracellular antioxidant synthesis, cell-mediated immune responses, induction of DNA damage repair systems, and differentiation of regulatory T cells.

Mushrooms, Tumors, and Immunity: An Update

There is significant interest in the use of mushrooms and/or mushroom extracts as dietary supplements based on theories that they enhance immune function and promote health. To some extent, select mushrooms have been shown to have stimulatory action on immune responsiveness, particularly when studied in vitro. However, despite their widespread use for potential health benefits, there is a surprising paucity of epidemiologic and experimental studies that address the biologic activities of mushrooms after oral administration to animals or humans. There have been a number of studies that have addressed the ability of mushrooms to modulate mononuclear cell activation and the phenotypic expression of cytokines and their cognate receptors. There have also been a number of attempts to determine antitumor activities of mushrooms. Such studies are important because many of the components of mushrooms do potentially have significant biologic activity. All data, however, should be tempered by the Possibility that there are toxic levels of metals, including arsenic, lead, cadmium, and mercury as well as the presence of radioactive contamination with 137Cs. In this review, we will Present the comparative biology with respect to both immunological and antitumor activities of mushroom extracts and also highlight the need for further evidence-based research.

Noble metal nanoparticle-induced oxidative stress modulates tumor associated macrophages (TAMs) from an M2 to M1 phenotype: An in vitro approach

Diagnosis of cancer and photothermal therapy using optoelectronic properties of noble metal nanoparticles (NPs) has established a new therapeutic approach for treating cancer. Here we address the intrinsic properties of noble metal NPs (gold and silver) as well as the mechanism of their potential antitumor activity. For this, the study addresses the functional characterization of tumor associated macrophages (TAMs) isolated from murine fibrosarcoma induced by a chemical carcinogen, 3-methylcholanthrene (MCA). We have previously shown antitumor activity of both gold nanoparticles (AuNPs) and silver nanoparticle (AgNPs) in vivo in a murine fibrosarcoma model. In the present study, it has been seen that AuNPs and AgNPs modulate the reactive oxygen species (ROS) and reactive nitrogen species (RNS) production, suppressing the antioxidant system of cells (TAMs). Moreover, the antioxidant-mimetic action of these NPs maintain the ROS and RNS levels in TAMs which act as second messengers to activate the proinflammatory signaling cascades. Thus, while there is a downregulation of tumor necrosis factor-α (TNF-α) and Interleukin-10 (IL-10) in the TAMs, the proinflammatory cytokine Interleukin-12 (IL-12) is upregulated resulting in a polarization of TAMs from M2 (anti-inflammatory) to M1 (pro-inflammatory) nature.

The Reactive Oxygen Species in Macrophage Polarization: Reflecting Its Dual Role in Progression and Treatment of Human Diseases

High heterogeneity of macrophage is associated with its functions in polarization to different functional phenotypes depending on environmental cues. Macrophages remain in balanced state in healthy subject and thus macrophage polarization may be crucial in determining the tissue fate. The two distinct populations, classically M1 and alternatively M2 activated, representing the opposing ends of the full activation spectrum, have been extensively studied for their associations with several disease progressions. Accumulating evidences have postulated that the redox signalling has implication in macrophage polarization and the key roles of M1 and M2 macrophages in tissue environment have provided the clue for the reasons of ROS abundance in certain phenotype. M1 macrophages majorly clearing the pathogens and ROS may be crucial for the regulation of M1 phenotype, whereas M2 macrophages resolve inflammation which favours oxidative metabolism. Therefore how ROS play its role in maintaining the homeostatic functions of macrophage and in particular macrophage polarization will be reviewed here. We also review the biology of macrophage polarization and the disturbance of M1/M2 balance in human diseases. The potential therapeutic opportunities targeting ROS will also be discussed, hoping to provide insights for development of target-specific delivery system or immunomodulatory antioxidant for the treatment of ROS-related diseases.

Senescence associated secretory phenotype profile from primary lung mice fibroblasts depends on the senescence induction stimuli

Cellular senescence is a multifactorial phenomenon of growth arrest and distorted function, which has been recognized as an important feature during tumor suppression mechanisms and a contributor to aging. Senescent cells have an altered secretion pattern called Senescence-Associated Secretory Phenotype (SASP) that comprises a complex mix of factors including cytokines, growth factors, chemokines, and matrix metalloproteinases. SASP has been related with local inflammation that leads to cellular transformation and neurodegenerative diseases. Various pathways for senescence induction have been proposed; the most studied is replicative senescence due to telomere attrition called replicative senescence (RS). However, senescence can be prematurely achieved when cells are exposed to diverse stimuli such as oxidative stress (stress-induced premature senescence, SIPS) or proteasome inhibition (proteasome inhibition-induced premature senescence, PIIPS). SASP has been characterized in RS and SIPS but not in PIIPS. Hence, our aim was to determine SASP components in primary lung fibroblasts obtained from CD-1 mice induced to senescence by PIIPS and compare them to RS and SIPS. Our results showed important variations in the 62 cytokines analyzed, while SIPS and RS showed an increase in the secretion of most cytokines, and in PIIPS only 13 were incremented. Variations in glutathione-redox balance were also observed in SIPS and RS, and not in PIIPS. All senescence types SASP displayed a pro-inflammatory profile and increased proliferation in L929 mice fibroblasts exposed to SASP. However, the behavior observed was not exactly the same, suggesting that the senescence induction pathway might encompass dissimilar responses in adjacent cells and promote different outcomes.

Excretory/secretory proteome of 14-day schistosomula, Schistosoma japonicum

Schistosomiasis remains a serious public health problem, with 200 million people infected and 779 million people at risk worldwide. The schistosomulum is the early stage of the complex lifecycle of Schistosoma japonicum in their vertebrate hosts, and is the main target of vaccine-induced protective immunity. Excretory/secretory (ES) proteins play a major role in host-parasite interactions and ES protein compositions of schistosomula of S. japonicum have not been characterized to date. In the present study, the proteome of ES proteins from 14 day schistosomula of S. japonicum was analyzed by liquid chromatography/tandem mass spectrometry and 713 unique proteins were finally identified. Gene ontology and pathway analysis revealed that identified proteins were mainly involved in carbohydrate metabolism, degradation, response to stimulus, oxidation-reduction, biological regulation and binding. Flow cytometry analysis demonstrated that thioredoxin peroxidase identified in this study had the effect on inhibiting MHCII and CD86 expression on LPS-activated macrophages. The present study provides insight into the growth and development of the schistosome in the final host and valuable information for screening vaccine candidates for schistosomiasis.

A physical/psychological and biological stress combine to enhance endoplasmic reticulum stress

The generation of an immune response against infectious and other foreign agents is substantially modified by allostatic load, which is increased with chemical, physical and/or psychological stressors. The physical/psychological stress from cold-restraint (CR) inhibits host defense against Listeria monocytogenes (LM), due to early effects of the catecholamine norepinephrine (NE) from sympathetic nerves on β1-adrenoceptors (β1AR) of immune cells. Although CR activates innate immunity within 2h, host defenses against bacterial growth are suppressed 2-3 days after infection (Cao and Lawrence 2002). CR enhances inducible nitric oxide synthase (iNOS) expression and NO production. The early innate activation leads to cellular reduction-oxidation (redox) changes of immune cells. Lymphocytes from CR-treated mice express fewer surface thiols. Splenic and hepatic immune cells also have fewer proteins with free thiols after CR and/or LM, and macrophages have less glutathione after the in vivo CR exposure or exposure to NE in vitro. The early induction of CR-induced oxidative stress elevates endoplasmic reticulum (ER) stress, which could interfere with keeping phagocytized LM within the phagosome or re-encapsuling LM by autophagy once they escape from the phagosome. ER stress-related proteins, such as glucose-regulated protein 78 (GRP78), have elevated expression with CR and LM. The results indicate that CR enhances the unfolded protein response (UPR), which interferes with host defenses against LM. Thus, it is postulated that increased stress, as exists with living conditions at low socioeconomic conditions, can lower host defenses against pathogens because of oxidative and ER stress processes.

Hyperoxia promotes polarization of the immune response in ovalbumin-induced airway inflammation, leading to a TH17 cell phenotype

Previous studies have demonstrated that hyperoxia-induced stress and oxidative damage to the lungs of mice lead to an increase in IL-6, TNF-α, and TGF-β expression. Together, IL-6 and TGF-β have been known to direct T cell differentiation toward the TH17 phenotype. In the current study, we tested the hypothesis that hyperoxia promotes the polarization of T cells to the TH17 cell phenotype in response to ovalbumin-induced acute airway inflammation. Airway inflammation was induced in female BALB/c mice by intraperitoneal sensitization and intranasal introduction of ovalbumin, followed by challenge methacholine. After the methacholine challenge, animals were exposed to hyperoxic conditions in an inhalation chamber for 24 h. The controls were subjected to normoxia or aluminum hydroxide dissolved in phosphate buffered saline. After 24 h of hyperoxia, the number of macrophages and lymphocytes decreased in animals with ovalbumin-induced airway inflammation, whereas the number of neutrophils increased after ovalbumin-induced airway inflammation. The results showed that expression of Nrf2, iNOS, T-bet and IL-17 increased after 24 of hyperoxia in both alveolar macrophages and in lung epithelial cells, compared with both animals that remained in room air, and animals with ovalbumin-induced airway inflammation. Hyperoxia alone without the induction of airway inflammation lead to increased levels of TNF-α and CCL5, whereas hyperoxia after inflammation lead to decreased CCL2 levels. Histological evidence of extravasation of inflammatory cells into the perivascular and peribronchial regions of the lungs was observed after pulmonary inflammation and hyperoxia. Hyperoxia promotes polarization of the immune response toward the TH17 phenotype, resulting in tissue damage associated with oxidative stress, and the migration of neutrophils to the lung and airways. Elucidating the effect of hyperoxia on ovalbumin-induced acute airway inflammation is relevant to preventing or treating asthmatic patients that require oxygen supplementation to reverse the hypoxemia.

KCa3.1/IK1 Channel Regulation by cGMP-Dependent Protein Kinase (PKG) via Reactive Oxygen Species and CaMKII in Microglia: An Immune Modulating Feedback System?

The intermediate conductance Ca²⁺-activated K⁺ channel, KCa3.1 (IK1/SK4/KCNN4) is widely expressed in the innate and adaptive immune system. KCa3.1 contributes to proliferation of activated T lymphocytes, and in CNS-resident microglia, it contributes to Ca²⁺ signaling, migration, and production of pro-inflammatory mediators (e.g., reactive oxygen species, ROS). KCa3.1 is under investigation as a therapeutic target for CNS disorders that involve microglial activation and T cells. However, KCa3.1 is post-translationally regulated, and this will determine when and how much it can contribute to cell functions. We previously found that KCa3.1 trafficking and gating require calmodulin (CaM) binding, and this is inhibited by cAMP kinase (PKA) acting at a single phosphorylation site. The same site is potentially phosphorylated by cGMP kinase (PKG), and in some cells, PKG can increase Ca²⁺, CaM activation, and ROS. Here, we addressed KCa3.1 regulation through PKG-dependent pathways in primary rat microglia and the MLS-9 microglia cell line, using perforated-patch recordings to preserve intracellular signaling. Elevating cGMP increased both the KCa3.1 current and intracellular ROS production, and both were prevented by the selective PKG inhibitor, KT5823. The cGMP/PKG-evoked increase in KCa3.1 current in intact MLS-9 microglia was mediated by ROS, mimicked by applying hydrogen peroxide (H₂O₂), inhibited by a ROS scavenger (MGP), and prevented by a selective CaMKII inhibitor (mAIP). Similar results were seen in alternative-activated primary rat microglia; their KCa3.1 current required PKG, ROS, and CaMKII, and they had increased ROS production that required KCa3.1 activity. The increase in current apparently did not result from direct effects on the channel open probability (P_o) or Ca²⁺ dependence because, in inside-out patches from transfected HEK293 cells, single-channel activity was not affected by cGMP, PKG, H₂O₂ at normal or elevated intracellular Ca²⁺. The regulation pathway we have identified in intact microglia and MLS-9 cells is expected to have broad implications because KCa3.1 plays important roles in numerous cells and tissues.

Killing of Staphylococcus aureus in murine macrophages by chloroquine used alone and in combination with ciprofloxacin or azithromycin

This study aimed to determine any alteration in the killing of Staphylococcus aureus in murine peritoneal macrophages when chloroquine (CQ) is used alone compared with when it is used in combination with ciprofloxacin (CIP) or azithromycin (AZM). The study also aimed to find out the implication of reactive oxygen species (ROS) production and cytokine release in the intracellular killing of S. aureus in macrophages. We present here data obtained with a model of S. aureus-infected mouse peritoneal macrophages in which the intracellular growth of the bacteria and the influence of antibiotics was monitored for 30, 60, and 90 minutes in the presence or absence of CQ along with the production of ROS and alteration in levels of antioxidant enzymes and cytokines. It was observed that S. aureus-triggered cytokine response was regulated when macrophages were co-cultured with CQ and AZM as compared with CQ stimulation only. It can be suggested that action of AZM in mediating bacterial killing is enhanced by the presence of CQ, indicating enhanced uptake of AZM during early infection that may be essential for bacteria killing by AZM. Reduction of oxidative stress burden on the S. aureus-infected macrophages may pave the way for better killing of internalized S. aureus by CQ plus ciprofloxacin (CIP) or CQ plus AZM. Based on these observations, one may speculate that in an inflammatory milieu, CQ loaded with AZM elicits a stronger proinflammatory response by increasing the intracellular uptake of AZM or CIP, thus enabling the immune system to mount a more robust and prolonged response against intracellular pathogens.

Metallothionein and stress combine to affect multiple organ systems

Metallothioneins (MTs) are a family of low molecular weight, cysteine-rich, metal-binding proteins that have a wide range of functions in cellular homeostasis and immunity. MTs can be induced by a variety of conditions including metals, glucocorticoids, endotoxin, acute phase cytokines, stress, and irradiation. In addition to their important immunomodulatory functions, MTs can protect essential cellular compartments from toxicants, serve as a reservoir of essential heavy metals, and regulate cellular redox potential. Many of the roles of MTs in the neuroinflammation, intestinal inflammation, and stress response have been investigated and were the subject of a session at the 6th International Congress on Stress Proteins in Biology and Medicine in Sheffield, UK. Like the rest of the cell stress response, there are therapeutic opportunities that arise from an understanding of MTs, and these proteins also provide potential insights into the world of the heat shock protein.

The protective immune response produced in dogs after primary vaccination with the LiESP/QA-21 vaccine (CaniLeish®) remains effective against an experimental challenge one year later

Control of canine leishmaniasis is an important objective for the benefit of dogs living in or visiting endemic areas and for public health because of the zoonotic nature of this disease. Resistance or susceptibility to developing canine leishmaniasis after exposure to Leishmania infantum is primarily determined by the ability of the immune system to develop an appropriate Th1-dominated specific response to the parasite. For this reason there is a need for effective canine vaccines that can decrease the number of dogs developing progressive infections. In this study, we followed the impact of the LiESP/QA-21 canine vaccine (composed of excreted-secreted proteins of L. infantum and the QA-21 saponin adjuvant), recently launched commercially in Europe, on selected humoral and cellular immune parameters following an infectious intravenous challenge with L. infantum promastigotes administered one year after the primary vaccine course. We also followed parasitological parameters to determine the parasitological status of the challenged dogs. In contrast to controls, vaccinated dogs retained significantly stronger cell-mediated immune responses against the parasite despite a virulent challenge and had significantly lower mean parasite burdens at the end of the study, associated with a lower probability of developing active infections. These results confirm that the immune responses generated by vaccination with LiESP/QA-21 are still effective against an intravenous challenge one year after the primary vaccine course.

The adjuvant effect induced by di-(2-ethylhexyl) phthalate (DEHP) is mediated through oxidative stress in a mouse model of asthma

Di-(2-ethylhexyl) phthalate, as the most commonly used plasticizer, is considered to be related to the asthma prevalence. There are studies affirming that the DEHP has an adjuvant effect in the pathogenesis of allergy asthma. Oxidative stress is one possible pathway for DEHP-adjuvant effect. Thus, this study explored whether DEHP could induce adjuvant effect in mouse asthma model via oxidative stress pathway. Male BALB/c mice were randomly divided into six groups: (1) saline group, (2) DEHP group, (3) ovalbumin (OVA) group, (4) DEHP+OVA group, (5) OVA+vitamin E (Vit E) group, (6) DEHP+OVA+Vit E group. The exposure dose of DEHP was 30 mg/kg body weight (bw)/day. After 18 days of the exposure protocol. Reactive oxygen species (ROS), glutathione (GSH) and malonaldehyde (MDA) levels and biomarkers related to asthma model were measured. Collectively, these data indicated higher ROS and MDA levels and lower GSH contents in DEHP+OVA group than that in OVA group, while Vit E, an antioxidant, could restore ROS, MDA and GSH levels to control levels and attenuate the DEHP and/or OVA effects. Our observations suggested that there was a relationship between oxidative stress and the adjuvant effect induced by DEHP in this mouse asthma model.