Heat shock protein 70: roles in multiple sclerosis

The heat shock protein DNAJB8 inhibits pseudorabies virus replication by autophagy

Pseudorabies virus (PRV) effectively utilizes numerous host proteins and pathways to establish a successful infection. Consequently, it becomes imperative to investigate novel host factors implicated in viral infections to gain a deeper understanding of PRV pathogenesis. In this study, we reveal that the host heat shock protein, DNAJB8, functions as a negative regulator in PRV replication. Our findings indicated that both mRNA and protein levels of DNAJB8 were downregulated in cells infected with PRV. Further analysis demonstrated that overexpressing DNAJB8 suppressed PRV replication, whereas its knockdown enhanced viral replication. From a mechanistic perspective, DNAJB8 promoted cellular autophagy, subsequently impeding viral replication. Additionally, we discovered that the transcription factor SOX30 regulated DNAJB8 expression, thereby influencing viral replication. Collectively, these findings enhance our comprehension of the roles played by DNAJB8 and SOX30 in viral replication, broadening our knowledge of virus-host interactions.

Calycosin Enhances Heat Shock Related-Proteins in H9c2 Cells to Modulate Survival and Apoptosis against Heat Shock

Heat shock proteins (HSPs), which function as chaperones, are activated in response to various environmental stressors. In addition to their role in diverse aspects of protein production, HSPs protect against harmful protein-related stressors. Calycosin exhibits numerous beneficial properties. This study aims to explore the protective effects of calycosin in the heart under heat shock and determine its underlying mechanism. H9c2 cells, western blot, TUNEL staining, flow cytometry, and immunofluorescence staining were used. The time-dependent effects of heat shock analyzed using western blot revealed increased HSP expression for up to 2[Formula: see text]h, followed by protein degradation after 4[Formula: see text]h. Hence, a heat shock damage duration of 4[Formula: see text]h was chosen for subsequent investigations. Calycosin administered post-heat shock demonstrated dose-dependent recovery of cell viability. Under heat shock conditions, calycosin prevented the apoptosis of H9c2 cells by upregulating HSPs, suppressing p-JNK, enhancing Bcl-2 activation, and inhibiting cleaved caspase 3. Calycosin also inhibited Fas/FasL expression and activated cell survival markers (p-PI3K, p-ERK, p-Akt), indicating their cytoprotective properties through PI3K/Akt activation and JNK inhibition. TUNEL staining and flow cytometry confirmed that calycosin reduced apoptosis. Moreover, calycosin reversed the inhibitory effects of quercetin on HSF1 and Hsp70 expression, illustrating its role in enhancing Hsp70 expression through HSF1 activation during heat shock. Immunofluorescence staining demonstrated HSF1 translocation to the nucleus following calycosin treatment, emphasizing its cytoprotective effects. In conclusion, calycosin exhibits pronounced protective effects against heat shock-induced damages by modulating HSP expression and regulating key signaling pathways to promote cell survival in H9c2 cells.

Putative Roles and Therapeutic Potential of the Chaperone System in Amyotrophic Lateral Sclerosis and Multiple Sclerosis

The putative pathogenic roles and therapeutic potential of the chaperone system (CS) in amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS) are reviewed to provide a bibliographic and conceptual platform for launching research on the diagnostic and therapeutic applications of CS components. Various studies suggest that dysfunction of the CS contributes to the pathogenesis of ALS and MS, and here, we identify some of the implicated CS members. The physiology and pathophysiology of the CS members can be properly understood if they are studied or experimentally or clinically manipulated for diagnostic or therapeutic purposes, bearing in mind that they belong to a physiological system with multiple interacting and dynamic components, widespread throughout the body, intra- and extracellularly. Molecular chaperones, some called heat shock protein (Hsp), are the chief components of the CS, whose canonical functions are cytoprotective. However, abnormal chaperones can be etiopathogenic factors in a wide range of disorders, chaperonopathies, including ALS and MS, according to the data reviewed. Chaperones typically form teams, and these build functional networks to maintain protein homeostasis, the canonical role of the CS. However, members of the CS also display non-canonical functions unrelated to protein homeostasis. Therefore, chaperones and other members of the CS, if abnormal, may disturb not only protein synthesis, maturation, and migration but also other physiological processes. Thus, in elucidating the role of CS components in ALS and MS, one must look at protein homeostasis abnormalities and beyond, following the clues emerging from the works discussed here.

Scaffold Proteins in Autoimmune Disorders

Cells transmit information to the external environment and within themselves through signaling molecules that modulate cellular activities. Aberrant cell signaling disturbs cellular homeostasis causing a number of different diseases, including autoimmunity. Scaffold proteins, as the name suggests, serve as the anchor for binding and stabilizing signaling proteins at a particular locale, allowing both intra and intercellular signal amplification and effective signal transmission. Scaffold proteins play a critical role in the functioning of tight junctions present at the intersection of two cells. In addition, they also participate in cleavage formation during cytokinesis, and in the organization of neural synapses, and modulate receptor management outcomes. In autoimmune settings such as lupus, scaffold proteins can lower the cell activation threshold resulting in uncontrolled signaling and hyperactivity. Scaffold proteins, through their binding domains, mediate protein- protein interaction and play numerous roles in cellular communication and homeostasis. This review presents an overview of scaffold proteins, their influence on the different signaling pathways, and their role in the pathogenesis of autoimmune and auto inflammatory diseases. Since these proteins participate in many roles and interact with several other signaling pathways, it is necessary to gain a thorough understanding of these proteins and their nuances to facilitate effective target identification and therapeutic design for the treatment of autoimmune disorders.

A comprehensive review of the interaction between COVID-19 spike proteins with mammalian small and major heat shock proteins

Coronavirus disease 2019 (COVID-19) is a novel disease that had devastating effects on human lives and the country's economies worldwide. This disease shows similar parasitic traits, requiring the host's biomolecules for its survival and propagation. Spike glycoproteins severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 spike protein) located on the surface of the COVID-19 virus serve as a potential hotspot for antiviral drug development based on their structure. COVID-19 virus calls into action the chaperonin system that assists the attacker, hence favoring infection. To investigate the interaction that occurs between SARS-CoV-2 spike protein and human molecular chaperons (HSPA8 and sHSP27), a series of steps were carried out which included sequence attainment and analysis, followed by multiple sequence alignment, homology modeling, and protein-protein docking which we performed using Cluspro to predict the interactions between SARS-CoV-2 spike protein and human molecular chaperones of interest. Our findings depicted that SARS-CoV-2 spike protein consists of three distinct chains, chains A, B, and C, which interact forming hydrogen bonds, hydrophobic interactions, and electrostatic interactions with both human HSPA8 and HSP27 with -828.3 and -827.9 kcal/mol as binding energies for human HSPA8 and -1166.7 and -1165.9 kcal/mol for HSP27.

Mining Autoimmune-Disorder-Linked Molecular-Mimicry Candidates in Clostridioides difficile and Prospects of Mimic-Based Vaccine Design: An In Silico Approach

Molecular mimicry, a phenomenon in which microbial or environmental antigens resemble host antigens, has been proposed as a potential trigger for autoimmune responses. In this study, we employed a bioinformatics approach to investigate the role of molecular mimicry in Clostridioides difficile-caused infections and the induction of autoimmune disorders due to this phenomenon. Comparing proteomes of host and pathogen, we identified 23 proteins that exhibited significant sequence homology and were linked to autoimmune disorders. The disorders included rheumatoid arthritis, psoriasis, Alzheimer's disease, etc., while infections included viral and bacterial infections like HIV, HCV, and tuberculosis. The structure of the homologous proteins was superposed, and RMSD was calculated to find the maximum deviation, while accounting for rigid and flexible regions. Two sequence mimics (antigenic, non-allergenic, and immunogenic) of ≥10 amino acids from these proteins were used to design a vaccine construct to explore the possibility of eliciting an immune response. Docking analysis of the top vaccine construct C2 showed favorable interactions with HLA and TLR-4 receptor, indicating potential efficacy. The B-cell and T-helper cell activity was also simulated, showing promising results for effective immunization against C. difficile infections. This study highlights the potential of C. difficile to trigger autoimmunity through molecular mimicry and vaccine design based on sequence mimics that trigger a defensive response.

Transgenerational inheritance of wing development defects in Drosophila melanogaster induced by cadmium

The transgenerational inheritance of phenotype induced by environmental factors is a new focus in epigenetic research. In this study, Drosophila melanogaster (F₀) was cultured in the medium containing cadmium (Cd, 4.5 mg/kg) from eggs to adults, and offspring (F₁-F₄) were continuously kept in standard medium (without cadmium). The phenotype analysis showed that cadmium induced developmental defects on wings and apoptosis in the wing disc cells of Drosophila (F₀). The wing defects were transmitted for at least four generations even without Cd afterwards. And the effect on the mRNA expression of wing development related genes (shg, omb, F-actin, Mekk1) can be maintained for at least two or three generations. More importantly, under cadmium stress, the post-translational modification (PTM) on the histones H3K4me3 in the third instar larvae and ovaries or testes of adult flies increased significantly, while the levels of H3K9me3 and H3K27me3 decreased significantly. The expression of histone methylation related genes (dSet-1, ash1, Lsd1) increased significantly and these changes can be transmitted to offspring from one or two generations in ovaries or testes. These results suggest that the phenotypic defects of wings caused by cadmium can be inherited to the offspring, and this transgenerational inheritance effect may be related to the epigenetic regulation of histone methylation. Therefore, the adaptability of offspring should be considered when evaluating the toxicity and environmental risk of cadmium.

The effect of Urtica dioica extract on oxidative stress, heat shock proteins, and brain histopathology in multiple sclerosis model

Multiple sclerosis (MS) results from the destruction of myelin and focal inflammation. The study aimed to evaluate the effect of hydroalcoholic extract of Urtica dioica on oxidative stress, heat shock proteins, and brain histopathology in multiple sclerosis model. Sixty male C57BL/6 mice were divided into six groups of 10. Groups included positive control, negative control, and treatment groups with U. dioica extract at a dose of 50, 100, 200, and 400 mg/kg for 21 days (three times a week). The MS model was developed by a diet containing 0.2% cuprizone for 6 weeks. A section of brains was evaluated with Luxol Fast Blue staining and the other part evaluated with heat shock protein (HSP) kits 60 and 70, total antioxidant capacity (TAC), and malondialdehyde (MDA). In sections of corpus callosum, the highest amount of myelin was observed in the negative controls, while the use of cuprizone in the positive controls caused the destruction and reduction of myelin. The use of U. dioica extract in therapeutic groups except at a dose of 50 mg/kg could reduce myelin degradation to some extent and lead to remyelination. However, myelin levels in treatment groups were not significantly different from any of the negative and positive controls. Although HSP60 decreased in the treatment groups, there was no significant difference between the positive and negative controls. Treatment with this extract significantly reduced the amount of HSP70 compared with the positive controls. The decreased TAC and increased MDA in positive controls indicated oxidative stress, respectively. Furthermore, the extract led to an increase and decrease of TAC and MDA in the treatment groups, respectively. However, only the MDA level was significantly different from that of the positive controls. Therefore, the antioxidant effects of U. dioica extract could decrease cuprizone-induced oxidative stress and be effective in improving demyelination.

Current and Future Biomarkers in Multiple Sclerosis

Multiple sclerosis (MS) is a debilitating autoimmune disorder. Currently, there is a lack of effective treatment for the progressive form of MS, partly due to insensitive readout for neurodegeneration. The recent development of sensitive assays for neurofilament light chain (NfL) has made it a potential new biomarker in predicting MS disease activity and progression, providing an additional readout in clinical trials. However, NfL is elevated in other neurodegenerative disorders besides MS, and, furthermore, it is also confounded by age, body mass index (BMI), and blood volume. Additionally, there is considerable overlap in the range of serum NfL (sNfL) levels compared to healthy controls. These confounders demonstrate the limitations of using solely NfL as a marker to monitor disease activity in MS patients. Other blood and cerebrospinal fluid (CSF) biomarkers of axonal damage, neuronal damage, glial dysfunction, demyelination, and inflammation have been studied as actionable biomarkers for MS and have provided insight into the pathology underlying the disease process of MS. However, these other biomarkers may be plagued with similar issues as NfL. Using biomarkers of a bioinformatic approach that includes cellular studies, micro-RNAs (miRNAs), extracellular vesicles (EVs), metabolomics, metabolites and the microbiome may prove to be useful in developing a more comprehensive panel that addresses the limitations of using a single biomarker. Therefore, more research with recent technological and statistical approaches is needed to identify novel and useful diagnostic and prognostic biomarker tools in MS.

HSP70iQ435A to subdue autoimmunity and support anti-tumor responses

Developing immunosuppressive therapies for autoimmune diseases comes with a caveat that immunosuppression may promote the risk of developing other conditions or diseases. We have previously shown that biolistic delivery of an expression construct encoding inducible HSP70 (HSP70i) with one amino acid modification in the dendritic cell (DC) activating moiety 435-445 (HSP70iQ435A) to mouse skin resulted in significant immunosuppressive activity of autoimmune vitiligo, associated with fewer tissue infiltrating T cells. To prepare HSP70iQ435A as a potential therapeutic for autoimmune vitiligo, in this study we evaluated whether and how biolistic delivery of HSP70iQ435A in mice affects anti-tumor responses. We found that HSP70iQ435A in fact supports anti-tumor responses in melanoma-challenged C57BL/6 mice. Biolistic delivery of the HSP70iQ435A-encoding construct to mice elicited significant anti-HSP70 titers, and anti-HSP70 IgG and IgM antibodies recognize surface-expressed and cytoplasmic HSP70i in human and mouse melanoma cells. A peptide scan revealed that the anti-HSP70 antibodies recognize a specific C-terminal motif within the HSP70i protein. The antibodies elicited surface CD107A expression among mouse NK cells, representative of antibody-mediated cellular cytotoxicity (ADCC), supporting the concept, that HSP70iQ435A-encoding DNA elicits a humoral response to the stress protein expressed selectively on the surface of melanoma cells. Thus, besides limiting autoimmunity and inflammation, HSP70iQ435A elicits humoral responses that limit tumor growth and may be used in conjunction with immune checkpoint inhibitors to not only control tumor but to also limit adverse events following tumor immunotherapy.

Differential Proteomic Analysis of Astrocytes and Astrocytes-Derived Extracellular Vesicles from Control and Rai Knockout Mice: Insights into the Mechanisms of Neuroprotection

Reactive astrocytes are a hallmark of neurodegenerative disease including multiple sclerosis. It is widely accepted that astrocytes may adopt alternative phenotypes depending on a combination of environmental cues and intrinsic features in a highly plastic and heterogeneous manner. However, we still lack a full understanding of signals and associated signaling pathways driving astrocyte reaction and of the mechanisms by which they drive disease. We have previously shown in the experimental autoimmune encephalomyelitis mouse model that deficiency of the molecular adaptor Rai reduces disease severity and demyelination. Moreover, using primary mouse astrocytes, we showed that Rai contributes to the generation of a pro-inflammatory central nervous system (CNS) microenvironment through the production of nitric oxide and IL-6 and by impairing CD39 activity in response to soluble factors released by encephalitogenic T cells. Here, we investigated the impact of Rai expression on astrocyte function both under basal conditions and in response to IL-17 treatment using a proteomic approach. We found that astrocytes and astrocyte-derived extracellular vesicles contain a set of proteins, to which Rai contributes, that are involved in the regulation of oligodendrocyte differentiation and myelination, nitrogen metabolism, and oxidative stress. The HIF-1α pathway and cellular energetic metabolism were the most statistically relevant molecular pathways and were related to ENOA and HSP70 dysregulation.

Association of miRNA and mRNA Levels of the Clinical Onset of Multiple Sclerosis Patients

Simple Summary

In this study, we investigated the effect of microRNAs on the expression level of neuroprotective proteins, heat shock proteins, and sirtuin in peripheral blood mononuclear cells in the development of multiple sclerosis. Our results show that the gene expression of neurotrophins, heat shock proteins, SIRT1, and miRNAs by the immune cells of MS is d changed. A decrease in the expression of the BDNF and SIRT1 genes and an increase in the expression of miR-132-3p, miR-34a, and miR-132 in PBMCs may indicate an inhibition of the neuroprotective function of these cells, which may be associated with the transition of the immune system towards inflammation in the development of multiple sclerosis.

Abstract

Multiple sclerosis (MS) is a demyelinating disease characterized by chronic inflammation of the central nervous system, in which many factors can act together to influence disease susceptibility and progression. To date, the exact cause of MS is still unclear, but it is believed to result from an abnormal response of the immune system to one or more myelin antigens that develops in genetically susceptible individuals after their exposure to a, as yet undefined, causal agent. In our study, we assessed the effect of microRNAs on the expression level of neuroprotective proteins, including neurotrophins (BDNF and NT4/5), heat shock proteins (HSP70 and HSP27), and sirtuin (SIRT1) in peripheral blood mononuclear cells in the development of multiple sclerosis. The analysis of dysregulation of miRNA levels and the resulting changes in target mRNA/protein expression levels could contribute to a better understanding of the etiology of multiple sclerosis, as well as new alternative methods of diagnosis and treatment of this disease. The aim of this study was to find a link between neurotrophins (BDNF and NT4), SIRT1, heat shock proteins (HSP27 and HSP27), and miRNAs that are involved in the development of multiple sclerosis. The analysis of the selected miRNAs showed a negative correlation of SIRT1 with miR-132 and miR-34a and of BDNF with 132-3p in PBMCs, which suggests that the miRNAs we selected may regulate the expression level of the studied genes.

Heat Exposure and Multiple Sclerosis-A Regional and Temporal Analysis

Multiple sclerosis (MS) is a neurological disorder that progressively distorts the myelination of axons within the central nervous system (CNS). Increased core body temperature or metabolism as a result of exercise are common causes of short-term exacerbations of neurological symptoms in MS. About 60–80% of patients with MS experience a worsening of their symptoms when exposed to heat. In comparison, less data are available on the relationship between ambient meteorological conditions (e.g., temperature and relative humidity (RH)) and fluctuations in such variables in relation to MS symptoms. Thus, this study examined associations between time-lagged exposure to meteorological conditions and risk of a clinic visit due to MS among US veterans between 2010 and 2013. This study leveraged data from the Veterans Affairs (VA) and National Climactic Data Center (NCDC) for the continental US, partitioned into eight climate zones. We used a case crossover design to assess the risk of a MS clinic visit with respect to several meteorological conditions. Location-specific time-lagged daily (ambient) exposure to temperature, RH, and temperature variations (standard deviation (SD) of temperature) were computed (up to 30 days) for each case (i.e., day of MS visit) and control (a randomly assigned date ± 90–270 days prior to visit). Statistical analyses were conducted to examine independent associations between the selected meteorological conditions and risk of MS visits at the national and regional levels. A total of 533,066 patient visits received a MS diagnosis (International Classifications of Diseases (ICD)-9 code = 340). The Northeast (NE) and Upper Midwest (UMW) regions reported the highest frequency of clinic visits due to MS. Clinic visits were 9% more likely to occur in the spring, summer, and fall months (March–October) than in the winter (OR = 1.089; 95% CI = 1.076–1.103; p < 0.01). In the univariate analyses, the SD of temperature, temperature, and temperature–RH interaction were positively associated with an elevated risk of a MS clinic visit, while the RH was negatively associated with the risk for a clinic visit. In multivariate analyses, the strongest association of a MS clinic visit was observed with the SD of the temperature (OR = 1.012; 95% CI 1.008–1.017; p < 0.01). These associations between MS clinic visits and meteorological conditions varied across climate regions, with the strongest associations being observed in the LMW, UMW, DSW, and NE zones. The SD of the temperature was again the strongest associated predictor when examined regionally. Temperature variations and temperature–RH interactions (a proxy of the heat index) showed significant associations with MS clinic visits. These associations varied across climate regions when examined geographically. Our findings have implications for the management of MS in severe or recurrent cases, especially considering the impending changes in the daily temperature variations and intensity of the heatwaves expected with the intensification of global warming.

Glioblastoma: Is There Any Blood Biomarker with True Clinical Relevance?

Glioblastoma (GBM) is the most frequent malignant primary brain tumor in adults, characterized by a highly aggressive, inflammatory and angiogenic phenotype. It is a remarkably heterogeneous tumor at several levels, including histopathologically, radiographically and genetically. The 2016 update of the WHO Classification of Tumours of the Central Nervous System highlighted molecular parameters as paramount features for the diagnosis, namely IDH1/2 mutations that distinguish primary and secondary GBM. An ideal biomarker is a molecule that can be detected/quantified through simple non- or minimally invasive methods with the potential to assess cancer risk; promote early diagnosis; increase grading accuracy; and monitor disease evolution and treatment response, as well as fundamentally being restricted to one aspect. Blood-based biomarkers are particularly attractive due to their easy access and have been widely used for various cancer types. A number of serum biomarkers with multiple utilities for glioma have been reported that could classify glioma grades more precisely and provide prognostic value among these patients. At present, screening for gliomas has no clinical relevance. This is because of the low incidence, the lack of sensitive biomarkers in plasma, and the observation that gliomas may develop apparently de novo within few weeks or months. To the best of our knowledge, there is no routine use of a serum biomarker for clinical follow-up. The purpose of this paper is to review the serum biomarkers described in the literature related to glioblastoma and their possible relationship with clinical features.

Could the Heat Shock Proteins 70 Family Members Exacerbate the Immune Response in Multiple Sclerosis? An in Silico Study

Multiple sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system. It represents one of the main causes of neurological disability in young people. In MS, the autoimmune response is directed against myelin antigens but other possible bio-molecular markers are investigated. The aim of this work was, through an in silico study, the evaluation of the transcriptional modifications between healthy subjects and MS patients in six brain areas (corpus callosum, hippocampus, internal capsule, optic chiasm, frontal and parietal cortex) in order to identify genes representative of the disease. Our results show the upregulation of the Heat Shock Proteins (HSPs) HSPA1A, HSPA1B, HSPA7, HSPA6, HSPH1 and HSPA4L of the HSP70 family, among which HSPA1A and HSPA1B are upregulated in all the brain areas. HSP70s are molecular chaperones indispensable for protein folding, recently associated with immune system maintenance. The little overexpression of the HSPs protects the cells from stress but extreme upregulation can contribute to the MS pathogenesis. We also investigated the genes involved in the immune system that result in overall upregulation in the corpus callosum, hippocampus, internal capsule, optic chiasm and are absent in the cortex. Interestingly, the genes of the immune system and the HSP70s have comparable levels of expression.

Response to oxidative stress of peripheral blood mononuclear cells from multiple sclerosis patients and healthy controls

The complex scenario of multiple sclerosis (MS) pathology involves several mechanisms, including oxidative stress response. The heat shock proteins (HSPs) are important for the protection of the cells; however, their role in MS is not clear. The present research is focused on the response of peripheral blood mononuclear cells (PBMCs) to oxidative stress and to the involvement of HSP70-2 (a protein coded by the HSPA1B gene, located in the MHC class III). To this aim, we challenged PBMCs from MS patients and healthy controls with hydrogen peroxide. Specifically, PBMCs mitochondrial activity, HSP70-2 protein expression and the production of intracellular reactive oxygen species were assessed. These parameters were also related to the HSP70-2 rs1061581 polymorphism, which is linked to the risk of developing MS. Moreover, mitochondrial activity and HSP70-2 protein levels were also related to disease severity. Overall, our results indicate that PBMCs, from both MS patients and healthy controls, may display a similar response towards an oxidative insult; within this context, HSP70-2 does not seem to be central in the protection of PBMCs. Nevertheless, the HSP70-2 rs1061581 polymorphism is related to ROS levels and appears to have a role in the different expression of HSP70-2 under oxidative stimulus.

Down-regulated miR-374c and Hsp70 promote Th17 cell differentiation by inducing Fas expression in experimental autoimmune encephalomyelitis

OBJECTIVE

Fas is a positive regulator of Th17 cells differentiation in experimental autoimmune encephalomyelitis (EAE). However, its upstream regulators are still not fully determined. This study was designed to explore the upstream regulators of Fas in regulating Th17 cells differentiation in EAE.

METHODS

The mouse model of EAE was established by myelin oligodendrocyte glycoprotein injection. Th17 cells differentiation was induced by IL-23, IL-6 and TGF-β.

RESULTS

Down-regulated Hsp70 and miR-374c and up-regulated Fas were observed in the spleen and brain of EAE mice. Hsp70 overexpression evidently reduced Fas protein level, but not mRNA level. The luciferase reporter assay indicated that miR-374c targets Fas. Overexpression of miR-374c down-regulated the mRNA and protein level of Fas. The concentration of IL-17A in CD4+ T-cells was reduced by miR-374c or Hsp70 overexpression, and Fas overexpression altered this trend. Hsp70 did not regulate the expression of miR-374c, and likewise, miR-374c did not regulate the expression of Hsp70. Further results suggested that Hsp70 and miR-374c regulated Fas expression through different ways to affect Th17 cells differentiation in EAE.

CONCLUSIONS

This study suggested that down-regulated miR-374c and Hsp70 promote Th17 cell differentiation by inducing Fas expression in EAE.

Stem Cell-Derived Exosomes as Nanotherapeutics for Autoimmune and Neurodegenerative Disorders

To dissect therapeutic mechanisms of transplanted stem cells and develop exosome-based nanotherapeutics in treating autoimmune and neurodegenerative diseases, we assessed the effect of exosomes secreted from human mesenchymal stem cells (MSCs) in treating multiple sclerosis using an experimental autoimmune encephalomyelitis (EAE) mouse model. We found that intravenous administration of exosomes produced by MSCs stimulated by IFNγ (IFNγ-Exo) (i) reduced the mean clinical score of EAE mice compared to PBS control, (ii) reduced demyelination, (iii) decreased neuroinflammation, and (iv) upregulated the number of CD4+CD25+FOXP3+ regulatory T cells (Tregs) within the spinal cords of EAE mice. Co-culture of IFNγ-Exo with activated peripheral blood mononuclear cells (PBMCs) cells in vitro reduced PBMC proliferation and levels of pro-inflammatory Th1 and Th17 cytokines including IL-6, IL-12p70, IL-17AF, and IL-22 yet increased levels of immunosuppressive cytokine indoleamine 2,3-dioxygenase. IFNγ-Exo could also induce Tregs in vitro in a murine splenocyte culture, likely mediated by a third-party accessory cell type. Further, IFNγ-Exo characterization by deep RNA sequencing suggested that IFNγ-Exo contains anti-inflammatory RNAs, where their inactivation partially hindered the exosomes potential to induce Tregs. Furthermore, we found that IFNγ-Exo harbors multiple anti-inflammatory and neuroprotective proteins. These results not only shed light on stem cell therapeutic mechanisms but also provide evidence that MSC-derived exosomes can potentially serve as cell-free therapies in creating a tolerogenic immune response to treat autoimmune and central nervous system disorders.

Contribution of LTi and TH17 cells to B cell aggregate formation in the central nervous system in a mouse model of multiple sclerosis

Background

In a subgroup of patients suffering from progressive multiple sclerosis (MS), which is an inflammation-mediated neurodegenerative disease of the central nervous system (CNS), B cell aggregates were discovered within the meninges. Occurrence of these structures was associated with a more severe disease course and cortical histopathology. We have developed the B cell-dependent MP4-induced experimental autoimmune encephalomyelitis (EAE) as a mouse model to mimic this trait of the human disease. The aim of this study was to determine a potential role of lymphoid tissue inducer (LTi) and T_H17 cells in the process of B cell aggregate formation in the MP4 model.

Methods

We performed flow cytometry of cerebellar and splenic tissue of MP4-immunized mice in the acute and chronic stage of the disease to analyze the presence of CD3⁻CD5⁻CD4⁺RORγt⁺ LTi and CD3⁺CD5⁺CD4⁺RORγt⁺ T_H17 cells. Myelin oligodendrocyte glycoprotein (MOG):35–55-induced EAE was used as B cell-independent control model. We further determined the gene expression profile of B cell aggregates using laser capture microdissection, followed by RNA sequencing.

Results

While we were able to detect LTi cells in the embryonic spleen and adult intestine, which served as positive controls, there was no evidence for the existence of such a population in acute or chronic EAE in neither of the two models. Yet, we detected CD3⁻CD5⁻CD4⁻RORγt⁺ innate lymphoid cells (ILCs) and T_H17 cells in the CNS, the latter especially in the chronic stage of MP4-induced EAE. Moreover, we observed a unique gene signature in CNS B cell aggregates compared to draining lymph nodes of MP4-immunized mice and to cerebellum as well as draining lymph nodes of mice with MOG:35–55-induced EAE.

Conclusion

The absence of LTi cells in the cerebellum suggests that other cells might take over the function as an initiator of lymphoid tissue formation in the CNS. Overall, the development of ectopic lymphoid organs is a complex process based on an interplay between several molecules and signals. Here, we propose some potential candidates, which might be involved in the formation of B cell aggregates in the CNS of MP4-immunized mice.

Genome-wide identification and analysis of the eQTL lncRNAs in multiple sclerosis based on RNA-seq data

The pathogenesis of multiple sclerosis (MS) is significantly regulated by long noncoding RNAs (lncRNAs), the expression of which is substantially influenced by a number of MS-associated risk single nucleotide polymorphisms (SNPs). It is thus hypothesized that the dysregulation of lncRNA induced by genomic variants may be one of the key molecular mechanisms for the pathology of MS. However, due to the lack of sufficient data on lncRNA expression and SNP genotypes of the same MS patients, such molecular mechanisms underlying the pathology of MS remain elusive. In this study, a bioinformatics strategy was applied to obtain lncRNA expression and SNP genotype data simultaneously from 142 samples (51 MS patients and 91 controls) based on RNA-seq data, and an expression quantitative trait loci (eQTL) analysis was conducted. In total, 2383 differentially expressed lncRNAs were identified as specifically expressing in brain-related tissues, and 517 of them were affected by SNPs. Then, the functional characterization, secondary structure changes and tissue and disease specificity of the cis-eQTL SNPs and lncRNA were assessed. The cis-eQTL SNPs were substantially and specifically enriched in neurological disease and intergenic region, and the secondary structure was altered in 17.6% of all lncRNAs in MS. Finally, the weighted gene coexpression network and gene set enrichment analyses were used to investigate how the influence of SNPs on lncRNAs contributed to the pathogenesis of MS. As a result, the regulation of lncRNAs by SNPs was found to mainly influence the antigen processing/presentation and mitogen-activated protein kinases (MAPK) signaling pathway in MS. These results revealed the effectiveness of the strategy proposed in this study and give insight into the mechanism (SNP-mediated modulation of lncRNAs) underlying the pathology of MS.

Therapeutic potentials of ginger for treatment of Multiple sclerosis: A review with emphasis on its immunomodulatory, anti-inflammatory and anti-oxidative properties

Multiple sclerosis (MS) is characterized by chronic inflammatory response-induced demyelination of the neurons and degeneration of the axons within the central nervous system (CNS). A complex network of immunopathological-, inflammatory- and oxidative parameters involve in the development and advancement of MS. The anti-inflammatory, immunomodulatory and anti-oxidative characteristics of the ginger and several of its components have been indicated in some of experimental and clinical investigations. The possible therapeutic potentials of ginger and its ingredients in the treatment of MS may exert mainly through the regulation of the Th1-, Th2-, Th9-, Th17-, Th22- and Treg cell-related immune responses, down-regulation of the B cell-related immune responses, modulation of the macrophages-related responses, modulation of the production of pro- and anti-inflammatory cytokines, down-regulation of the arachidonic acid-derived mediators, interfering with the toll like receptor-related signaling pathways, suppression of the inflammasomes, down-regulation of the oxidative stress, reduction of the adhesion molecules expression, and down-regulation of the expression of the chemokines and chemokine receptors. This review aimed to provide a comprehensive knowledge regarding the immunomodulatory-, anti-inflammatory and anti-oxidative properties of ginger and its components, and highlight novel insights into the possible therapeutic potentials of this plant for treatment of MS. The review encourages more investigations to consider the therapeutic potentials of ginger and its effective components for managing of MS.

Heat Shock Protein 70 and The Risk of Multiple Sclerosis in The Iranian Population

Multiple sclerosis (MS) is a chronic disease of the central nervous system and one of the most common causes of neurological disability among those aged 20-40 years, particularly in women. Major histocompatibility complex (MHC) Class II genes are known to be involved in the development of MS. One of the important groups of this complex is the HSP gene family, especially HSP70, which is induced under stress conditions. The aim of the present case-control study was to determine the association between the heat shock protein 70 (HSP70) and risk of MS in Iranian patients by genotyping the rs1061581 gene polymorphism. A total of 50 relapsing-remitting MS (RRMS) patients and 50 healthy control subjects were considered for this study. Genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism (PCR- RFLP) method. PCR-RFLP results of twenty-five randomly selected samples were confirmed by DNA sequencing. Genotypic and allelic distributions were compared between the case and control groups. We observed no significant difference in the distribution of rs1061581 genotype and allele frequencies between RRMS patients and controls. In addition, there was no association between the HSP70 gene polymorphism and the clinical variables in the case group. Our data indicate that HSP70, in particular rs1061581, is unlikely to be involved in the susceptibility to or the severity of RRMS in Iranian patients. Further large prospective studies are required to confirm these findings.

Serum heat shock protein 70 levels as a biomarker for inflammatory processes in multiple sclerosis

Background

Inflammatory and neurodegenerative processes are hallmarks of multiple sclerosis (MS). The synthesis of the major stress-inducible heat shock protein 70 (Hsp70) is induced by inflammation.

Objective

The purpose of this study is to determine whether Hsp70 in serum can serve as a potential biomarker to distinguish inflammatory and neurodegenerative processes in MS.

Methods

Serum was obtained from 94 patients: 26 clinically isolated syndrome (CIS), 40 relapsing–remitting MS (RRMS), 19 secondary progressive MS (SPMS), and nine primary progressive MS (PPMS). As controls, serum samples were collected from patients with non-inflammatory neurological diseases (NINDs, n = 41), other inflammatory neurological diseases (OINDs, n = 28) and healthy donors (HDs, n = 114). Serum levels of Hsp70 were quantified using the enzyme-linked immunosorbent assay detecting free and liposomal Hsp70 (lipHsp70 ELISA).

Results

Patients with MS displayed significantly higher Hsp70 serum levels than HDs (p < 0.001) and significantly lower levels than OINDs (p = 0.001). A subgroup analysis revealed that Hsp70 serum levels of CIS/RRMS patients are significantly higher than those of patients with progressive MS (SPMS/PPMS) (p < 0.05).

Conclusion

Inflammation causes the release of Hsp70 into the blood. As CIS/RRMS are associated with higher Hsp70 serum levels than progressive MS, serum Hsp70 levels might provide a marker for inflammatory processes.

Heat shock protein 70 suppresses neuroinflammation induced by α-synuclein in astrocytes

Neuroinflammation triggered by activation of glial cells plays an important role in the pathophysiology of several neurodegenerative diseases including Parkinson's disease (PD). Besides microglia, astrocytes are also critical in initiating and perpetuating inflammatory process associated with PD. Heat shock protein 70 (Hsp70) is originally described as intracellular chaperone, however, recent study revealed that it had anti-inflammatory effects as well. The present study is designed to investigate whether Hsp70 mediates neuroinflammation in astrocytes. By employing α-synuclein (α-Syn) (A53T) aggregates on primary cultured astrocytes of rats, we found that astrocytes were activated and neuroinflammatory response was triggered, as indicated by over-expression of glial fibrillary acidic protein (GFAP), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), increased production of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). The data also showed that the neuroinflammatory response accompanied up-regulated Hsp70 expression. Moreover, over-expression of Hsp70 through transfection of Hsp70 cDNA plasmids could significantly reduce the production of TNF-α, IL-1β, and the expression of GFAP, COX-2 as well as iNOS. While inhibition of Hsp70 by VER155008 exacerbated neuroinflammatory response in astrocytes challenged by α-Syn aggregates. Further mechanistic study indicated that c-Jun N-terminal kinase (JNK) and nuclear factor-κB (NF-κB) signalings were responsible for the neuroinflammation, which was also regulated by Hsp70. These findings demonstrated that Hsp70 was an important modulator in astrocytes induced inflammation, and up-regulation of Hsp70 might be a potential regulating approach for neuroinflammation-related neurodegenerative diseases, such as PD.

RNA sequencing reveals resistance of TLR4 ligand-activated microglial cells to inflammation mediated by the selective jumonji H3K27 demethylase inhibitor

Persistent microglial activation is associated with the production and secretion of various pro-inflammatory genes, cytokines and chemokines, which may initiate or amplify neurodegenerative diseases. A novel synthetic histone 3 lysine 27 (H3K27) demethylase JMJD3 inhibitor, GSK-J4, was proven to exert immunosuppressive activities in macrophages. However, a genome-wide search for GSK-J4 molecular targets has not been undertaken in microglia. To study the immuno-modulatory effects of GSK-J4 at the transcriptomic level, triplicate RNA sequencing and quantitative real-time PCR analyses were performed with resting, GSK-J4-, LPS- and LPS + GSK-J4-challenged primary microglial (PM) and BV-2 microglial cells. Among the annotated genes, the transcriptional sequencing of microglia that were treated with GSK-J4 revealed a selective effect on LPS-induced gene expression, in which the induction of cytokines/chemokines, interferon-stimulated genes, and prominent transcription factors TFs, as well as previously unidentified genes that are important in inflammation was suppressed. Furthermore, we showed that GSK-J4 controls are important inflammatory gene targets by modulating STAT1, IRF7, and H3K27me3 levels at their promoter sites. These unprecedented results demonstrate that the histone demethylase inhibitor GSK-J4 could have therapeutic applications for neuroinflammatory diseases.

Heat Shock Proteins in Multiple Sclerosis

Multiple sclerosis (MS) is an immune-mediated and neurodegenerative central nervous system disease, mostly affect myelin sheaths. The MS pathogenesis is still under debate. It is influenced by genetic, environment factors. Heat shock proteins (HSPs) are highly conserved proteins seen in all organisms. Not only heat stress but also under many stress conditions they are overexpressed. Their roles in MS pathogenesis are highly correlated with their location (intracellular or extracellular). In this chapter, we will discuss the role of HSP in MS pathogenesis.

Bioinformatics evaluation of the possibility of heat shock proteins as autoantigens in multiple sclerosis based on molecular mimicry hypothesis

Molecular mimicry is the explanatory link between the heat shock proteins (HSPs) of infectious agents and triggering multiple sclerosis. Considering that there are many similarities between self- and bacterial-HSPs, the goal was to investigate a panel of 60- and 70kDa HSPs from a variety of bacteria in order to predict the role of each microorganism in triggering or progression of the disease under the molecular mimicry hypothesis. By clarifying the peptides meeting criteria for cross-reactivity and elucidating the role of each microorganism in MS pathogenesis, it would be easier to suggest more effective treatment and preventive strategies for this disease.

The lost correlation between heat shock protein 70 (HSPA1A) and plasminogen activator inhibitor-1 in patients with type 2 diabetes and albuminuria

We aimed to study the relation between plasma levels of stress-induced heat shock protein 70 (HSPA1A) with plasminogen activator inhibitor-1 (PAI-1) and high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (Apo-A1), and HDL-C/Apo-A1 ratio. In a matched case-control study on patients with diabetes (40 patients with albuminuria and 40 without albuminuria matched for age, sex, and body mass index), we observed that plasma levels of HSPA1A and PAI-1 are increased in patients with albuminuria (0.55 ± 0.02 vs. 0.77 ± 0.04 ng/ml, p value <0.001 for HSPA1A; 25.9 ± 2 vs. 31.8 ± 2.4 ng/ml, p value <0.05 for PAI-1). There was a significant correlation between HSPA1A and PAI-1 in diabetic patients without albuminuria (r = 0.28; p value = 0.04), but not in those with albuminuria (r = 0.07; p value = 0.63). No association was found between HSPA1A and HDL-C, between HSPA1A and Apo-A1, or between HSPA1A and HDL-C/Apo-A1 ratio. We concluded that there is a direct correlation between plasma HSPA1A and PAI-1 levels in patients with diabetes, which is lost when they develop albuminuria.

Unfolding the Role of Large Heat Shock Proteins: New Insights and Therapeutic Implications

Heat shock proteins (HSPs) of eukaryotes are evolutionarily conserved molecules present in all the major intracellular organelles. They mainly function as molecular chaperones and participate in maintenance of protein homeostasis in physiological state and under stressful conditions. Despite their relative abundance, the large HSPs, i.e., Hsp110 and glucose-regulated protein 170 (Grp170), have received less attention compared to other conventional HSPs. These proteins are distantly related to the Hsp70 and belong to Hsp70 superfamily. Increased sizes of Hsp110 and Grp170, due to the presence of a loop structure, result in their exceptional capability in binding to polypeptide substrates or non-protein ligands, such as pathogen-associated molecules. These interactions that occur in the extracellular environment during tissue injury or microbial infection may lead to amplification of an immune response engaging both innate and adaptive immune components. Here, we review the current advances in understanding these large HSPs as molecular chaperones in proteostasis control and immune modulation as well as their therapeutic implications in treatment of cancer and neurodegeneration. Given their unique immunoregulatory activities, we also discuss the emerging evidence of their potential involvement in inflammatory and immune-related diseases.

Harnessing the integrated stress response for the treatment of multiple sclerosis

Multiple sclerosis (MS) is a chronic demyelinating autoimmune disease of the central nervous system (CNS) with no known cure. Though a dozen immunomodulatory therapies exist, their impact on progression of disease appears limited. The field has hence focused on alternate strategies for treatment such as enhancing remyelination and CNS repair. Recent progress has been made on a third complimentary treatment approach that involves protecting oligodendrocytes, and the myelin they generate and maintain, from inflammatory-mediated death via enhancement of the integrated stress response (ISR). Studies in cells and mouse models of MS have demonstrated that the ISR, an innate protective pathway that maintains proteostasis, may be effectively harnessed to aid in the protection of oligodendrocytes and myelin during inflammation. With one ISR-modifying drug already in clinical trial and a number of potential future therapies under investigation, this approach may offer an important component in halting the progression of multiple sclerosis.

A role of Heat Shock Protein 70 in Photoreceptor Cell Death: Potential as a Novel Therapeutic Target in Retinal Degeneration

Retinal degenerative diseases (RDs) such as retinitis pigmentosa (RP) are a genetically heterogeneous group of disorders characterized by night blindness and peripheral vision loss, which caused by the dysfunction and death of photoreceptor cells. Although many causative gene mutations have been reported, the final common end stage is photoreceptor cell death. Unfortunately, no effective treatments or therapeutic agents have been discovered. Heat shock protein 70 (HSP70) is highly conserved and has antiapoptotic activities. A few reports have shown that HSP70 plays a role in RDs. Thus, we focused on the role of HSP70 in photoreceptor cell death. Using the N-methyl-N-nitrosourea (MNU)-induced photoreceptor cell death model in mice, we could examine two stages of the novel cell death mechanism; the early stage, including HSP70 cleavage through protein carbonylation by production of reactive oxygen species, lipid peroxidation and Ca(2+) influx/calpain activation, and the late stage of cathepsin and/or caspase activation. The upregulation of intact HSP70 expression by its inducer is likely to protect photoreceptor cells. In this review, we focus on the role of HSP70 and the novel cell death signaling process in RDs. We also describe candidate therapeutic agents for RDs.

HSPA12B regulates SSeCKS-mediated astrocyte inflammatory activation in neuroinflammation

Reactive astrocytosis has been considered either beneficial or detrimental effection in neuroinflammatory disease. HSPA12B, a new member belongs to the 70-kDa family of heat shock proteins (HSP70) which could modulate inflammatory response, also shows an connection with the astrocyte activation. Recently, it was reported that Src-Suppressed-C Kinase Substrate (SSeCKS) was detected in heat shock protein A12B (HSPA12B) interacting proteins using a yeast 2-hybrid system. SSeCKS, a major Lipopolysaccharide (LPS) response protein, has been involved in regulating astrocyte activation via production of proinflammatory factor in CNS inflammation. In this study, we found HSPA12B might regulate the expression and activity of SSeCKS to promote astrocyte inflammatory activation and release of inflammatory mediators, such as TNF-α and IL-1β in spinal cord primary astroglial cultures exposed to LPS treatment. The promoting mechanism of interaction between HSPA12B and SSeCKS on LPS-induced astrocyte activation was mediated via the activation of JNK and p38 signaling pathways but not ERK1/2 MAPK signaling pathway. HSPA12B binded to SSeCKS via its both N terminus consisted of amino acids 1-330 and C terminus consisted of amino acids 1278-1596. And, in vivo, we confirmed the interaction between HSPA12B and SSeCKS of astrocyte activation in the pathogenesis of EAE. The regulatory mechanisms of HSPA12B-SSeCKS interaction may possibly be the key therapeutic strategy of neuroinflammatory disease.

Involvement of serum HSP 70 in Guillain-Barré Syndrome: An exploratory study and a review of current literature

The evolutionary conserved family of heat shock proteins (HSP) is responsible for protecting cells against different types of stress. Although the levels of HSP can be readily measured in serum, the levels of HSP 70 in patients Guillain-Barre Syndrome (GBS) have not been studied before. To this aim we investigate whether patients with GBS (n=21) had altered serum HSP 70 levels compared to healthy controls (HC, n=9) and to patients affected by other immune disorders such as multifocal motor neuropathy (MMN, n=4) and chronic inflammatory demyelinating polyneuropathy (CIDP, n=6). The highest HSP 70 value (15.78 ± 1.72 ng/mL) was found in one patient in the GBS group, although we have found that serum HSP70 levels were significantly higher in 2 out of the 21 GBS patients (9.5%). Hence, it is of interest to underline that the patient with the highest HSP70 level, had also the best recovery rate. Моrе extensive research is required in order to support the hypothesis that HSP 70 serum concentration may be a useful biomarker for the prediction of remission outcome for GBS patients.

Hsp70 regulates immune response in experimental autoimmune encephalomyelitis

Heat shock protein (Hsp)70 is one of the most important stress-inducible proteins. Intracellular Hsp70 not only mediates chaperone-cytoprotective functions but can also block multiple steps in the apoptosis pathway. In addition, Hsp70 is actively released into the extracellular milieu, thereby promoting innate and adaptive immune responses. Thus, Hsp70 may be a critical molecule in multiple sclerosis (MS) pathogenesis and a potential target in this disease due to its immunological and cytoprotective functions. To investigate the role of Hsp70 in MS pathogenesis, we examined its immune and cytoprotective roles using both in vitro and in vivo experimental procedures. We found that Hsp70.1-deficient mice were more resistant to developing experimental autoimmune encephalomyelitis (EAE) compared with their wild-type (WT) littermates, suggesting that Hsp70.1 plays a critical role in promoting an effective myelin oligodendrocyte glycoprotein (MOG)-specific T cell response. Conversely, Hsp70.1-deficient mice that developed EAE showed an increased level of autoreactive T cells to achieve the same production of cytokines compared with the WT mice. Although a neuroprotective role of HSP70 has been suggested, Hsp70.1-deficient mice that developed EAE did not exhibit increased demyelination compared with the control mice. Accordingly, Hsp70 deficiency did not influence the vulnerability to apoptosis of oligodendrocyte precursor cells (OPCs) in culture. Thus, the immunological role of Hsp70 may be relevant in EAE, and specific therapies down-regulating Hsp70 expression may be a promising approach to reduce the early autoimmune response in MS patients.

Gene therapy with mitochondrial heat shock protein 70 suppresses visual loss and optic atrophy in experimental autoimmune encephalomyelitis

PURPOSE

To rescue visual loss and optic neuropathy in experimental autoimmune encephalomyelitis (EAE).

METHODS

Encephalomyelitis was induced in mice that received intravitreal injections of AAV2-mtHSP70Flag or AAV2-Cox8-mCherry. Additional mice were injected with AAV2-Cox8-mCherry, but not sensitized for EAE. Visual function was assessed by pattern electroretinograms (PERG) at 1, 3, and 6 months post injection (MPI). Optical coherence tomography (OCT) evaluated the thickness of the inner plexiform layer + nerve fiber layers at 1, 3, and 6 MPI. Retinas and optic nerves (ONs) of mice euthanized 6 MPI were processed for light and electron microscopy. Expression of mtHSP70Flag in the retina and ONs was evaluated by RT-PCR, immunofluorescence, and Western blotting. The activities of respiratory complexes I and III, as well as mitochondrial protein import were quantitated.

RESULTS

Expression: immunofluorescence revealed punctate and perinuclear expression of mtHSP70Flag that colocalized with mitochondrial porin in thy1.2 labeled retinal ganglion cells (RGCs). Immunoblotting and RT-PCR confirmed mtHSP70Flag expression in the retina and ON. Rescue: treatment with mtHSP70Flag resulted in a 44% increase in PERG amplitude and less delays in latency relative to the EAE-mCherry group that also showed progressive inner retinal thinning. At 6 MPI, the almost 50% loss of RGCs and optic nerve axons in EAE mice was suppressed by mtHSP70Flag. In addition, retinas of EAE-mtHSP70Flag mice showed nearly complete rescue of complex I and III activities that was reduced by one-third in the EAE-mCherry retinas. Lastly, reductions in import of COX8-mCherry into mitochondria of mice sensitized for EAE improved by 30% with mtHSP70Flag gene therapy.

CONCLUSIONS

Mitochondrial HSP70 ameliorates mitochondrial dysfunction that culminates in irreversible visual loss and atrophy of the optic nerve in EAE suggesting that it may be useful to prevent irreversible disability in patients with optic neuritis and multiple sclerosis (MS).

Are Hsp70 protein expression and genetic polymorphism implicated in multiple sclerosis inflammation?

Genetic and environmental factors contribute to disease Multiple Sclerosis (MS) susceptibility, the most prevalent neurological pathology affecting young individuals in Western countries. We focused our attention on HSP70-2, an inducible chaperon induced under stress conditions. Genotype analysis of HSP70-2 (+1267 A/G) polymorphism revealed a significant association between the minor allele G and presence of MS (OR:1.31, 95% CI: 1.02-1.69, P = 0.039). In addition, Hsp70-2 protein content in vitro from PBMC was significantly lower in MS patients with GG genotype compared to AA genotype, indicating an implication of the G allele of HSP70-2 gene polymorphism in the development of MS.

Multiple sclerosis: molecular mechanisms and therapeutic opportunities

The pathophysiology of multiple sclerosis (MS) involves several components: redox, inflammatory/autoimmune, vascular, and neurodegenerative. All of them are supported by the intertwined lines of evidence, and none of them should be written off. However, the exact mechanisms of MS initiation, its development, and progression are still elusive, despite the impressive pace by which the data on MS are accumulating. In this review, we will try to integrate the current facts and concepts, focusing on the role of redox changes and various reactive species in MS. Knowing the schedule of initial changes in pathogenic factors and the key turning points, as well as understanding the redox processes involved in MS pathogenesis is the way to enable MS prevention, early treatment, and the development of therapies that target specific pathophysiological components of the heterogeneous mechanisms of MS, which could alleviate the symptoms and hopefully stop MS. Pertinent to this, we will outline (i) redox processes involved in MS initiation; (ii) the role of reactive species in inflammation; (iii) prooxidative changes responsible for neurodegeneration; and (iv) the potential of antioxidative therapy.

IL-10 is significantly involved in HSP70-regulation of experimental subretinal fibrosis

Subretinal fibrosis is directly related to severe visual loss, especially if occurs in the macula, and is frequently observed in advanced age-related macular degeneration and other refractory eye disorders such as diabetic retinopathy and uveitis. In this study, we analyzed the immunosuppressive mechanism of subretinal fibrosis using the novel animal model recently demonstrated. Both TLR2 and TLR4 deficient mice showed significant enlargement of subretinal fibrotic area as compared with wild-type mice. A single intraocular administration of heat shock protein 70 (HSP70), which is an endogenous ligand for TLR2 and TLR4, inhibited subretinal fibrosis in wild-type mice but not in TLR2 and TLR4-deficient mice. Additionally, HSP70 induced IL-10 production in eyes from wild-type mice but was impaired in both TLR2- and TLR4-deficient mice, indicating that HSP70-TLR2/TLR4 axis plays an immunomodulatory role in subretinal fibrosis. Thus, these results suggest that HSP70-TLR2/TLR4 axis is a new therapeutic target for subretinal fibrosis due to prognostic CNV.

Epitopes of microbial and human heat shock protein 60 and their recognition in myalgic encephalomyelitis

Myalgic encephalomyelitis (ME, also called Chronic Fatigue Syndrome), a common disease with chronic fatigability, cognitive dysfunction and myalgia of unknown etiology, often starts with an infection. The chaperonin human heat shock protein 60 (HSP60) occurs in mitochondria and in bacteria, is highly conserved, antigenic and a major autoantigen. The anti-HSP60 humoral (IgG and IgM) immune response was studied in 69 ME patients and 76 blood donors (BD) (the Training set) with recombinant human and E coli HSP60, and 136 30-mer overlapping and targeted peptides from HSP60 of humans, Chlamydia, Mycoplasma and 26 other species in a multiplex suspension array. Peptides from HSP60 helix I had a chaperonin-like activity, but these and other HSP60 peptides also bound IgG and IgM with an ME preference, theoretically indicating a competition between HSP60 function and antibody binding. A HSP60-based panel of 25 antigens was selected. When evaluated with 61 other ME and 399 non-ME samples (331 BD, 20 Multiple Sclerosis and 48 Systemic Lupus Erythematosus patients), a peptide from Chlamydia pneumoniae HSP60 detected IgM in 15 of 61 (24%) of ME, and in 1 of 399 non-ME at a high cutoff (p<0.0001). IgM to specific cross-reactive epitopes of human and microbial HSP60 occurs in a subset of ME, compatible with infection-induced autoimmunity.

Glatiramer acetate treatment effects on gene expression in monocytes of multiple sclerosis patients

Background

Glatiramer acetate (GA) is a mixture of synthetic peptides used in the treatment of patients with relapsing-remitting multiple sclerosis (RRMS). The aim of this study was to investigate the effects of GA therapy on the gene expression of monocytes.

Methods

Monocytes were isolated from the peripheral blood of eight RRMS patients. The blood was obtained longitudinally before the start of GA therapy as well as after one day, one week, one month and two months. Gene expression was measured at the mRNA level by microarrays.

Results

More than 400 genes were identified as up-regulated or down-regulated in the course of therapy, and we analyzed their biological functions and regulatory interactions. Many of those genes are known to regulate lymphocyte activation and proliferation, but only a subset of genes was repeatedly differentially expressed at different time points during treatment.

Conclusions

Overall, the observed gene regulatory effects of GA on monocytes were modest and not stable over time. However, our study revealed several genes that are worthy of investigation in future studies on the molecular mechanisms of GA therapy.

Initial immunopathogenesis of multiple sclerosis: innate immune response

Multiple sclerosis (MS) is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system. The hallmark to MS is the demyelinated plaque, which consists of a well-demarcated hypocellular area characterized by the loss of myelin, the formation of astrocytic scars, and the mononuclear cell infiltrates concentrated in perivascular spaces composed of T cells, B lymphocytes, plasma cells, and macrophages. Activation of resident cells initiates an inflammatory cascade, leading to tissue destruction, demyelination, and neurological deficit. The immunological phenomena that lead to the activation of autoreactive T cells to myelin sheath components are the result of multiple and complex interactions between environment and genetic background conferring individual susceptibility. Within the CNS, an increase of TLR expression during MS is observed, even in the absence of any apparent microbial involvement. In the present review, we focus on the role of the innate immune system, the first line of defense of the organism, as promoter and mediator of cross reactions that generate molecular mimicry triggering the inflammatory response through an adaptive cytotoxic response in MS.

Unraveling the protein network of tomato fruit in response to necrotrophic phytopathogenic Rhizopus nigricans

Plants are endowed with a sophisticated defense mechanism that gives signals to plant cells about the immediate danger from surroundings and protects them from pathogen invasion. In the search for the particular proteins involved in fruit defense responses, we report here a comparative analysis of tomato fruit (Solanum lycopersicum cv. Ailsa Craig) infected by Rhizopus nigricans Ehrenb, which is a significant contributor to postharvest rot disease in fresh tomato fruits. In total, four hundred forty-five tomato proteins were detected in common between the non-infected group and infected tomato fruit of mature green. Forty-nine differentially expressed spots in 2-D gels were identified, and were sorted into fifteen functional groups. Most of these proteins participate directly in the stress response process, while others were found to be involved in several equally important biological processes: protein metabolic process, carbohydrate metabolic process, ethylene biosynthesis, and cell death and so on. These responses occur in different cellular components, both intra- and extracellular spaces. The differentially expressed proteins were integrated into several pathways to show the regulation style existing in tomato fruit host. The composition of the collected proteins populations and the putative functions of the identified proteins argue for their roles in pathogen-plant interactions. Collectively results provide evidence that several regulatory pathways contribute to the resistance of tomato fruit to pathogen.

A Sardinian map for multiple sclerosis

Multiple sclerosis (MS) is a complex autoimmune disease of the CNS. At present, MS etiology remains unknown, but it is believed to be caused by environmental factors acting on a genetic predisposition. Several studies suggest that different microorganisms could play a role in triggering autoimmunity, through immunological cross-reactivity or molecular mimicry. An overview of the knowledge regarding the bacteria involved in MS is given, placing emphasis on the newest candidate proposed: Mycobacterium avium subsp. paratuberculosis. This review will focus on discussing several arguments that might support a causal role for Mycobacterium avium subsp. paratuberculosis as an etiologic agent in MS. Additionally, a possible mechanism is postulated attempting to explain how the bacteria could initiate autoimmunity.

Diagnostic yield of heat shock protein 70 (HSP-70) and anti-HSP-70 in Behcet-induced uveitis

Heat shock proteins (HSPs) are intracellular proteins with pro- and anti-inflammatory actions, playing an important role in the pathogenesis of Behcet's disease (BD). Diagnosis of BD uveitis in early stages is still problematic, thus this study was undertaken to determine diagnostic values of serum HSP- and anti-HSP-70 in BD uveitis. Serum levels of HSP- and anti-HSP-70 were measured in 53 patients with BD (26 with and 27 without uveitis). In control group, 25 age- and sex-matched idiopathic uveitis patients were enrolled consecutively. Both groups had no medical problems save uveitis at the time of sampling. Confounders like medications were analysed subsequently. HSP- and anti-HSP-70 values were measured by commercial ELISA kits. Data were analysed by spss 11.5 and medcalc 11.5.1 software. The Mean HSP-70 serum levels were different among aforementioned subgroups (P = 0.001, anova). They were elevated in BD uveitis compared with BD without uveitis (4.84 ± 4.21 versus 2.24 ± 2.08 ng/ml; P = 0.045). HSP-70 in sera of BD uveitis was also higher than that parameter in patients with idiopathic uveitis (4.84 ± 4.21 versus 2.37 ± 3.30 ng/ml; P = 0.001; cut-off point value 1.0 9 ng/ml, 95% CI 0.61-0.86, P = 0.0002, ß = 0.06). However, there was not any statistical difference among those groups in the serum anti-HSP-70 levels (P = 0.63, anova). Multiple regression analysis demonstrated that among different confounders, only prednisolone increases and BD uveitis decreases HSP-70 levels independently. This prospective cross-sectional study suggested that HSP-70 serum level is impressed over the course of BD uveitis, and it could be utilized to diagnose or predict developing it.

Erythropoietin and autoimmune neuroinflammation: lessons from experimental autoimmune encephalomyelitis and experimental autoimmune neuritis

Erythropoietin (EPO) is known to have numerous biological functions. While its primary function is during haematopoiesis, recent studies have shown that EPO plays important role in cytoprotection, immunomodulation, and antiapoptosis. These secondary functions of EPO are integral to tissue protection following hypoxic injury, ischemia-reperfusion injury, and spinal cord injury in the central nervous system. This review focuses on experimental evidence documenting the neuroprotective effects of EPO in organ-specific autoimmune nervous system disorders such as experimental autoimmune encephalomyelitis (EAE) and experimental autoimmune neuritis (EAN). In addition, the immunomodulatory role of EPO in the pathogenesis of EAE and EAN animal models of human multiple sclerosis and Guillain-Barré syndrome, respectively, will be discussed.