Up-regulation of inducible heat shock protein-70 expression in multiple sclerosis patients

PGK1 modulates balance between pro- and anti-inflammatory cytokines by interacting with ITI-H4

Inter-α-trypsin inhibitor heavy chain 4 (ITI-H4) is one of the acute phase proteins and is mainly related with inflammatory diseases such as bacterial bloodstream infection and recurrent pregnancy loss (RPL). In a previous study, ITI-H4 was reported to be cleaved by kallikrein B1 (KLKB1) and its cleaved form induces the imbalance between pro- and anti-inflammatory cytokines. Therefore, in this study, putative substrates of ITI-H4 were isolated by immunoprecipitation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) analysis. Of those, phosphoglycerate kinase 1 (PGK1) was found to be a binding protein of ITI-H4. PGK1 increases the level of ITI-H4 expression and blocks the cleavage of ITI-H4 mediated by KLKB1. It also inhibits pro-inflammatory response by inhibiting the JAK2/STAT3 signaling pathway. Therefore, PGK1, a novel binding partner of ITI-H4, is expected to have cellular functions in the pathogenesis of ITI-H4-related inflammatory diseases.

Role of DAMPs and cell death in autoimmune diseases: the example of multiple sclerosis

Multiple sclerosis is a chronic neuroinflammatory demyelinating disease of the central nervous system (CNS) of unknown etiology and still incompletely clarified pathogenesis. The disease is generally considered a disorder resulting from a complex interplay between environmental risk factors and predisposing causal genetic variants. To examine the etiopathogenesis of the disease, two complementary pre-clinical models are currently discussed: the "outside-in" model proposing a peripherally elicited inflammatory/autoimmune attack against degraded myelin as the cause of the disease, and the "inside-out" paradigm implying a primary cytodegenerative process of cells in the CNS that triggers secondary reactive inflammatory/autoimmune responses against myelin debris. In this review, the integrating pathogenetic role of damage-associated molecular patterns (DAMPs) in these two scenario models is examined by focusing on the origin and sources of these molecules, which are known to promote neuroinflammation and, via activation of pattern recognition receptor-bearing antigen-presenting cells, drive and shape autoimmune responses. In particular, environmental factors are discussed that are conceptually defined as agents which produce endogenous DAMPs via induction of regulated cell death (RCD) or act themselves as exogenous DAMPs. Indeed, in the field of autoimmune diseases, including multiple sclerosis, recent research has focused on environmental triggers that cause secondary events in terms of subroutines of RCD, which have been identified as prolific sources of DAMPs. Finally, a model of a DAMP-driven positive feed-forward loop of chronic inflammatory demyelinating processes is proposed, aimed at reconciling the competing "inside-out" and "outside-in" paradigms.

Clinical and transcriptional recovery profiles in pediatric and adult multiple sclerosis patients

OBJECTIVE

To determine whether pediatric-onset multiple sclerosis (POMS) and adults-onset multiple sclerosis (AOMS) patients are different in initial disease severity and recovery and to investigate the associations with peripheral blood mononuclear cells (PBMCs) transcriptional profiles.

METHODS

Clinical and radiological severity of first and second relapses and 6-month recovery were analyzed in 2153 multiple sclerosis (MS) patients and compared between POMS (onset at 8-18years old) and AOMS (onset at 19-40 years old) patients. PBMCs transcriptomes of 15 POMS and 15 gender-matched AOMS patients were analyzed 6 months after the first relapse and compared to 55 age-matched healthy controls. Differentially Expressed Genes (DEGs) with a false discovery rate ≤ 10% were evaluated using the Partek software.

RESULTS

POMS had increased Expanded Disability Status Scale (EDSS) score at first and second relapses, higher brain gadolinium-enhancing T1-lesions volume at first relapse, and more complete recovery after both relapses compared to AOMS. POMS patients, who recovered completely from the first relapse, were characterized by 19 DEGs that were mainly related to suppression of antigen presentation. Six upstream regulators of these genes were differentially expressed between pediatric and adult healthy controls. POMS patients, who showed no recovery from the first relapse, were characterized by 28 DEGs that were mainly associated with B-cell activation. Five upstream regulators of these genes were differentially expressed between pediatric and adult healthy controls.

INTERPRETATION

POMS patients may have more severe first and second relapses than AOMS. However, most often, POMS have better recovery that may be attributed to PBMCs age-related transcriptional profiles associated with antigen presentation and B-cell activation.

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.

Stable transgenic C9orf72 zebrafish model key aspects of the ALS/FTD phenotype and reveal novel pathological features

A hexanucleotide repeat expansion (HRE) within the chromosome 9 open reading frame 72 (C9orf72) gene is the most prevalent cause of amyotrophic lateral sclerosis/fronto-temporal dementia (ALS/FTD). Current evidence suggests HREs induce neurodegeneration through accumulation of RNA foci and/or dipeptide repeat proteins (DPR). C9orf72 patients are known to have transactive response DNA binding protein 43 kDa (TDP-43) proteinopathy, but whether there is further cross over between C9orf72 pathology and the pathology of other ALS sub-types has yet to be revealed.

To address this, we generated and characterised two zebrafish lines expressing C9orf72 HREs. We also characterised pathology in human C9orf72-ALS cases. In addition, we utilised a reporter construct that expresses DsRed under the control of a heat shock promoter, to screen for potential therapeutic compounds.

Both zebrafish lines showed accumulation of RNA foci and DPR. Our C9-ALS/FTD zebrafish model is the first to recapitulate the motor deficits, cognitive impairment, muscle atrophy, motor neuron loss and mortality in early adulthood observed in human C9orf72-ALS/FTD. Furthermore, we identified that in zebrafish, human cell lines and human post-mortem tissue, C9orf72 expansions activate the heat shock response (HSR). Additionally, HSR activation correlated with disease progression in our C9-ALS/FTD zebrafish model. Lastly, we identified that the compound ivermectin, as well as riluzole, reduced HSR activation in both C9-ALS/FTD and SOD1 zebrafish models.

Thus, our C9-ALS/FTD zebrafish model is a stable transgenic model which recapitulates key features of human C9orf72-ALS/FTD, and represents a powerful drug-discovery tool.

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.

Pathophysiological abnormalities in the brains of Spontaneously Diabetic Torii-Lepr fa (SDT fatty) rats, a novel type 2 diabetic model

In recent years, a relationship between diabetes and neurodegenerative diseases, such as Parkinson's disease, Alzheimer disease or depression, has been proposed. In this study, pathophysiological changes in the brain, especially in the hippocampus, of male SDT fatty rats with obesity and hyperglycemia were investigated. Brains of SD rats and SDT fatty rats were collected at 32 and 58 weeks of age, and parietal cortical thickness and number of pyramidal cells in the hippocampal cornu ammonis 1 and 3 (CA1 and CA3) regions were measured. At 58 weeks of age, the parietal cortical thickness and number of pyramidal cells in the hippocampal CA1 and CA3 regions were lower in SDT fatty rats than in age-matched SD rats. Measurements of mRNA in rat brains at 58 weeks of age showed that the expression of genes related to inflammatory responses (S100a9, TNFα, NF-κB) was elevated in SDT fatty rats. From the aforementioned results, changes suggestive of brain atrophy and impairment in cognitive function were observed in male SDT fatty rat brains.

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.

Signaling via toll-like receptor 4 and CD40 in B cells plays a regulatory role in the pathogenesis of multiple sclerosis through interleukin-10 production

BACKGROUND

B cells play an important role in the development of multiple sclerosis (MS), but can also exhibit regulatory functions through IL-10 production. Toll-like receptors (TLR) and CD40 signaling are likely to be involved in this process.

OBJECTIVE

To investigate the ability of MS B cells to produce IL-10 in response to TLR stimulation in the presence or absence of CD40 co-stimulation.

METHODS

Peripheral blood mononuclear cells obtained from 34 MS patients and 24 matched healthy participants (HS) were stimulated through either TLR4 or TLR9 alone, or together with CD40. Intracellular cytokine production was analyzed by flow cytometry.

RESULTS

The frequency of IL-10-producing cells in total B cells after either TLR9 or CD40 stimulation was significantly lower in MS than HS, regardless of disease phase. The frequency of IL-10 producing B cells after TLR4 stimulation did not differ significantly between HS and MS, regardless of disease phase. TLR4 and CD40 co-stimulation synergistically increased the frequency of IL-10-producing but not pro-inflammatory cytokine-producing B cells at MS relapse. This effect was observed in both CD27^- naïve and CD27⁺ memory B cells. The frequency of IL-10-producing B cells following CD40 stimulation was significantly higher in interferon-β responders than non-treated MS patients. Finally, we confirmed that the frequency of IL-10-producing B cells positively correlated with IL-10 production quantity by B cells using magnetic-isolated B cells.

CONCLUSIONS

Cross-talk between TLR4 and CD40 signaling plays a crucial role in regulating IL-10 production by B cells during MS relapses, which may promote recovery from relapse. CD40 signaling in B cells is involved in the response to interferon-β in MS. Collectively, TLR4 and CD40 signaling in B cells may provide a promising target for MS therapy.

HSP27 and 70 expression in thymic epithelial tumors and benign thymic alterations: diagnostic, prognostic and physiologic implications

Thymic Epithelial Tumors (TETs), the most common tumors in the anterior mediastinum in adults, show a unique association with autoimmune Myasthenia Gravis (MG) and represent a multidisciplinary diagnostic and therapeutic challenge. Neither risk factors nor established biomarkers for TETs exist. Predictive and diagnostic markers are urgently needed. Heat shock proteins (HSPs) are upregulated in several malignancies promoting tumor cell survival and metastases. We performed immunohistochemical staining of HSP27 and 70 in patients with TETs (n = 101) and patients with benign thymic alterations (n = 24). Further, serum HSP27 and 70 concentrations were determined in patients with TETs (n = 46), patients with benign thymic alterations (n = 33) and volunteers (n = 49) by using ELISA. HSPs were differentially expressed in histologic types and pathological tumor stages of TETs. Weak HSP tumor expression correlated with worse freedom from recurrence. Serum HSP concentrations were elevated in TETs and MG, correlated with clinical tumor stage and histologic subtype and decreased significantly after complete tumor resection. To conclude, we found HSP expression in the vast majority of TETs, in physiologic thymus and staining intensities in patients with TETs have been associated with prognosis. However, although interesting and promising the role of HSPs in TETs as diagnostic and prognostic or even therapeutic markers need to be further evaluated.

Positive or negative involvement of heat shock proteins in multiple sclerosis pathogenesis: an overview

Multiple sclerosis (MS) is the most diffuse chronic inflammatory disease of the central nervous system. Both immune-mediated and neurodegenerative processes apparently play roles in the pathogenesis of this disease. Heat shock proteins (HSPs) are a family of highly evolutionarily conserved proteins; their expression in the nervous system is induced in a variety of pathologic states, including cerebral ischemia, neurodegenerative diseases, epilepsy, and trauma. To date, investigators have observed protective effects of HSPs in a variety of brain disease models (e.g. of Alzheimer disease and Parkinson disease). In contrast, unequivocal data have been obtained for their roles in MS that depend on the HSP family and particularly on their localization (i.e. intracellular or extracellular). This article reviews our current understanding of the involvement of the principal HSP families in MS.

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.