Expression Of High Mobility Group Box Protein 1 Research Articles

Glycyrrhizin, a High-Mobility Group Box 1 Inhibitor, Improves Lipid Metabolism and Suppresses Vascular Inflammation in Apolipoprotein E Knockout Mice

Background: High-mobility group box protein 1 (HMGB1) is known to have proinflammatory properties; however, the mechanisms by which HMGB1 influences immune responses during atherosclerosis (AS) development are not well understood. Thus, this study investigated the relationship between HMGB1 and vascular inflammation in Apoe^–/– mice and whether glycyrrhizin (GLY), a small inhibitor of HMGB1, could have atheroprotective effects in AS. Methods: Apoe^–/– mice on a high-fat diet were treated with GLY (50 mg/kg) or vehicle by gavage once daily for 12 weeks, respectively. Results: The GLY group exhibited significantly decreased serum lipid levels, atherosclerotic plaque deposition, and serum HMGB1 levels, as well as an increased Treg/Th17 ratio. The GLY group displayed increased interleukin-10 (IL-10) and IL-2 expression and decreased IL-17A and IL-6 expression. Furthermore, the GA treatment significantly reduced STAT3 phosphorylation in Th17 cells and increased STAT5 phosphorylation in Treg cells. Conclusions: Our findings indicate that the attenuation of atherosclerotic lesions in Apoe^–/– mice by GLY might be associated with the amelioration of lipid metabolism abnormalities, inhibition of HMGB1 expression, and alterations in the Treg/Th17 ratio.

MiR-142-3p Inhibits the Metastasis of Hepatocellular Carcinoma Cells by Regulating HMGB1 Gene Expression.

Non-coding small RNAs are involved in organism development, and their aberrant regulation induces various diseases, including hepatocellular carcinoma (HCC), but their exact mechanisms have not been determined. The aim was to investigate the role of miR-142-3p on HMGB1 expression in hepatocellular carcinoma. Expression levels of miR-142-3p in HCC tissues and cultured cells were measured by RT-PCR. The invasion and metastasis abilities of HepG2 cells according to Transwell migration and invasion assays, and protein expression was measured by western blotting. The present study reported that miR-142-3p promotes the invasion and migration of HCC cells. miR-142-3p levels are lower in HCC tissues than in adjacent non-cancerous tissues, suggesting a tumor suppressor role for miR-142-3p. Highmobility group box protein 1 (HMGB1) is an oncogene that promotes the metastasis of HCC. miR-142-3p or HMGB1 knockdown alone inhibits the invasion and migration of HCC cells, and HMGB1 overexpression impedes the effect of miR-142-3p. Further studies showed that HMGB1 is a direct target gene of miR-142-3p in HCC. miR-142-3p represses HMGB1 gene transcription by directly binding to the 3' untranslated region (UTR) of HMGB1, thereby inhibiting cancer cell invasion and migration. This study, for the first time, reports that miR-142-3p is a novel tumor suppressor that inhibits the invasion and migration of HCC cells by directly regulating gene transcription of HMGB1. Thus, miR-142-3p may be a potential diagnostic and therapeutic biomarker for HCC patients.

Ulinastatin protects the lungs of COPD rats through the HMGB1/TLR4 signaling pathway.

The present study aimed to investigate the protective mechanism of ulinastatin against lung injury. Rat models with chronic obstructive pulmonary disease (COPD) were used to provide guidance for the medical treatment of this disease. The rats were divided into three groups: A control group, a model group and an experimental group (each, n=10). With the exception of the control group, all of the rats were prepared as models of COPD, using the composite molding method of smoking and intratracheal instillation of lipopolysaccharide. The rats in the model group all received a conventional treatment, while the rats in the experimental group received ulinastatin. A small animal lung function detector was used to examine lung function. The forced expiratory volume/sec (FEV) was negatively correlated with the protein expression levels of Toll-like receptor 4 (TLR4) and high mobility group box protein 1 (HMGB1). Real-time fluorescence quantitative polymerase chain reaction and western blot analyses were used to detect TLR4, MyD88 (myeloid differentiation factor 88), TRAF-6 (TNF receptor-associated factor 6), LOX-1 (lectin-type oxidized LDL receptor 1) and HMGB1 mRNA, along with their protein expression levels. The lung function of rats in the model group was significantly decreased compared with in the control group (P<0.05). In the experimental group the lung function was significantly greater, when compared with in the model group; however, it remained lower than in the control group. The mRNA and protein expression levels of TLR4, MyD88, TRAF-6, LOX-1 and HMGB1 were significantly higher in the model group than in the control and experimental groups; however, levels in the experimental group were significantly higher when compared with in the control group (P<0.05). The TLR4 and HMGB1 expression levels were positively correlated in all groups, which indicated involvement of the HMGB1/TLR4 signaling pathway. The FEV was negatively correlated with the protein expression levels of TLR4 and HMGB1. Thus, the protective effect of ulinastatin in the lungs of rats with COPD is associated with changes in the HMGB1/TLR4 signaling pathway.

Gut Microbial Metabolite TMAO Induces Endothelial Dysfunction by Activating the HMGB1/TLR‐4 Signalling Pathway

The intestinal microbe derived metabolite trimethylamine N‐oxide (TMAO) is implicated in the pathogenesis of cardiovascular diseases. However, the molecular mechanisms of how TMAO induces atherosclerosis and CVD progression are still unclear. In this regard, high‐mobility group box protein 1 (HMGB1), an inflammatory mediator, has been reported to destroy cell‐cell junctions, resulting in vascular endothelial hyper permeability leading to endothelial dysfunction. The present study tested whether TMAO associated endothelial dysfunction results via HMGB1 activation in in vitro and in vivo models. Biochemical and RT‐PCR analysis showed that TMAO increased the HMGB1 expression in dose dependent manner in endothelial cells compared to control cells. However, prior treatment with glycyrrhizin, an HMGB1 binder abolished the TMAO‐induced HMGB1 production in endothelial cells. Furthermore, western blot and immunofluorescent analysis showed significant decrease in the expression of cell‐cell junction proteins ZO‐1, ZO‐2, Occludin and V‐cadherin in TMAO treated endothelial cells compared to control cells. However, prior treatment with glycyrrhizin attenuated the TMAO‐induced cell‐cell junction proteins disruption. In addition, TMAO induced the HMGB1 expression through TLR‐4 signalling pathway in endothelial cells. In in vivo studies, C57BL/6J wild mice were treated with 3 % choline chloride in drinking water to produce enhanced TMAO levels in plasma. Real time PCR analysis showed that HMGB1, TLR‐4 and inflammatory markers (ICAM &amp; VCAM) were significantly increased in carotid arteries of choline treated mice compared to control mice. In addition, it was also found that collagen I and III expression (fibrotic markers) were significantly increased in carotid arteries of choline treated mice. In conclusion, our results suggested that TMAO modulated endothelial cells phenotype via activating HMGB1 associated TLR‐4 signalling pathway.Support or Funding Informationsupported by NIH grant, DK104031This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

High Mobility Group Box Protein 1 Serves as a Potential Prognostic Marker of Lung Cancer and Promotes Its Invasion and Metastasis by Matrix Metalloproteinase-2 in a Nuclear Factor-κB-Dependent Manner.

Several studies have reported a significant role of high mobility group box protein 1 (HMGB1) in lung cancer. Nevertheless, there is a lack of knowledge regarding the expression of HMGB1 and its correlation with the clinicopathological features of lung cancer. In addition, the potential molecular mechanisms underlying the role of HMGB1 in lung cancer are still unknown. We therefore investigated the clinicopathological and prognostic significance as well as the potential role of HMGB1 in the development and progression of lung cancer. HMGB1 expression in the tumor tissues of the cohort correlated with clinicopathological features. Moreover, lung cell migration and invasion were significantly increased after treatment with HMGB1. The matrix metalloproteinase-2 (MMP-2) expression and activity were upregulated after treatment with HMGB1, while the upregulated expression of MMP-2 stimulated by HMGB1 in lung cancer cells was significantly reduced with the blockage of si-p65. These results indicated that HMGB1 expression was significantly associated with lung cancer progression. We also showed that HMGB1 promoted lung cancer invasion and metastasis by upregulating the expression and activity of MMP-2 in an NF-κB-dependent manner. Taken together, these data suggested that HMGB1 may be a potential prognosis and therapeutic marker for lung cancer.

Increased expression of high mobility group box protein 1 and vascular endothelial growth factor in placenta previa.

Placenta previa is often associated with preterm delivery, reduced birth weight, a higher frequency of placental accreta and postpartum haemorrhage, and increased likelihood of blood transfusion. The present study aimed to examine the expression of high mobility group box protein 1 (HMGB1) in the placenta of women with or without placenta previa. The study group consisted of placental tissues obtained from women with or without placenta previa. The expression levels of HMGB1 and vascular endothelial growth factor (VEGF) were evaluated in the placental tissues using reverse transcription‑quantitative polymerase chain reaction, western blotting and immunohistochemistry. The mRNA expression levels of HMGB1 and VEGF were significantly increased in the placenta previa group compared with in the normal group. In addition, the placenta previa group exhibited increased HMGB1 and VEGF staining in vascular endothelial cells and trophoblasts. There were no significant differences in the expression of HMGB1 or VEGF between groups with or without placenta accreta or postpartum haemorrhage. The present study hypothesised that the increased expression of HMGB1 in the placenta may be associated with the pathogenesis of placenta previa by regulating the expression of the proangiogenic factor VEGF.

Scar Prevention and Enhanced Wound Healing Induced by Polydeoxyribonucleotide in a Rat Incisional Wound-Healing Model.

High-mobility group box protein-1 (HMGB-1) plays a central role in the inflammatory network, and uncontrolled chronic inflammation can lead to excessive scarring. The aim of this study was to evaluate the anti-inflammatory effects of polydeoxyribonucleotide (PDRN) on scar formation. Sprague-Dawley rats (n = 30) underwent dorsal excision of the skin, followed by skin repair. PDRN (8 mg/kg) was administered via intraperitoneal injection for three (PDRN-3 group, n = 8) or seven (PDRN-7 group, n = 8) days, and HMGB-1 was administered via intradermal injection in addition to PDRN treatment for three days (PDRN-3+HMGB-1 group; n = 6). The scar-reducing effects of PDRN were evaluated in the internal scar area and by inflammatory cell counts using histology and immunohistochemistry. Western blot, immunohistochemistry and immunofluorescence assays were performed to observe changes in type I and type III collagen and the expression of HMGB-1 and CD45. Treatment with PDRN significantly reduced the scar area, inflammatory cell infiltration and the number of CD45-positive cells. In addition, the increased expression of HMGB-1 observed in the sham group was significantly reduced after treatment with PDRN. Rats administered HMGB-1 in addition to PDRN exhibited scar areas with inflammatory cell infiltration similar to the sham group, and the collagen synthesis effects of PDRN were reversed. In summary, PDRN exerts anti-inflammatory and collagen synthesis effects via HMGB-1 suppression, preventing scar formation. Thus, we believe that the anti-inflammatory and collagen synthesis effects of PDRN resulted in faster wound healing and decreased scar formation.

HMGB1 is negatively correlated with the development of endometrial carcinoma and prevents cancer cell invasion and metastasis by inhibiting the process of epithelial-to-mesenchymal transition.

High-mobility group box protein 1 (HMGB1), a nuclear protein that plays a significant role in DNA architecture and transcription, was correlated with the progression of some types of cancer. However, the role of HMGB1 in endometrial cancer cell invasion and metastasis remains unexplored. HMGB1 expression was initially assessed by immunohistochemistry and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in normal endometrial tissue and endometrial carcinoma tissue. High expressions of HMGB1 protein were detected in normal endometrial tissues; however, in endometrial cancer tissues, the expressions of HMGB1 were found to be very weak. Furthermore, HMGB1 expressions were negatively correlated with advanced stage and lymph node metastasis in endometrial cancer. Then by RT-qPCR, Western blot and immunocytochemistry, HMGB1 was also detected in primary cultured endometrial cells and four kinds of endometrial cancer cell lines (Ishikawa, HEC-1A, HEC-1B and KLE). We found that the expression of HMGB1 was much higher in normal endometrial cells than in endometrial cancer cells, and reduced expression levels of HMGB1 were observed especially in the highly metastatic cell lines. Using lentivirus transfection, HMGB1 small hairpin RNA was constructed, and this infected the lowly invasive endometrial cancer cell lines, Ishikawa and HEC-1B. HMGB1 knockdown significantly enhanced the proliferation, invasion and metastasis of endometrial cancer cells and induced the process of epithelial-to-mesenchymal transition. These results can contribute to the development of a new potential therapeutic target for endometrial cancer.

HMGB1-mediated autophagy decreases sensitivity to oxymatrine in SW982 human synovial sarcoma cells.

Oxymatrine (OMT) is a type of alkaloid extracted from a traditional Chinese medicinal herb, Sophora flavescens. Although the antitumor activities of OMT have been observed in various cancers, there are no reports regarding the effects of OMT on human synovial sarcoma. In the present study, we analyzed the antitumor activities of OMT in SW982 human synovial sarcoma cells and determine whether high mobility group box protein 1 (HMGB1)-mediated autophagy was associated with its therapeutic effects. We found that OMT exhibited antitumor activity in SW982 cells and facilitated increases in autophagy. Inhibition of autophagy by 3-MA or ATG7 siRNA increased the level of apoptosis, which indicated that OMT-induced autophagy protected cells from the cytotoxicity of OMT. Administration of OMT to SW982 cells increased the expression of HMGB1. When HMGB1 was inhibited via HMGB1-siRNA, OMT-induced autophagy was decreased, and apoptosis was increased. Furthermore, we found that HMGB1-siRNA significantly increased the expression of p-Akt and p-mTOR. OMT-induced autophagy may be mediated by the Akt/mTOR pathway, and HMGB1 plays a vital role in the regulation of autophagy. Therefore, we believe that combining OMT with an inhibitor of autophagy or HMGB1 may make OMT more effective in the treatment of human synovial sarcoma.

399 - Glycyrrhizin Could Inhibit HMGB1-MMP-9 Signaling and Prevent Hemorrhagic Transformation in Ischemic Stroke with Delayed T-PA Treatment

Tissue plasminogen activator (t-PA) has restrict therapeutic window for ischemic stroke and hemorrhagic transformation (HT) is the major complications. High mobility group box protein 1 (HMGB1) and MMPs are critical targets for reducing HT. Glycyrrhizin is an antioxidant isolated from Glycyrrhiza glabr a. We hypothesize that glycyrrhizin could inhibit HMGB1, MMPs, reduce HT and improve survival rates in ischemic stroke with delayed t-PA tretament. Male SD rats were subjected middle cerebral artery occlusion (MCAO) for 5 hours plus 19 hours of reperfusion. T-PA (10 mg/kg) was intravenously administrated at 4.5 hours after MCAO and continuously injected for 30 min. Glycyrrhizin (30 mg/kg) was administrated at onset of t-PA treatment and saline was used as control. Major discoveries are as below: (1) Delayed t-PA treatment had increased mortality rate, brain swelling, hemorrhagic transformation with the increase of HMGB1 and MMP-9 expression. (2) Glycyrrhizin significantly inhibited HMGB1 and MMP-9, attenuated HT, decreased mortality and improved neurological outcomes. In conclusion, glycyrrhizin could be an adjuvant therapy with t-PA to improve the therapeutic outcome for ischemic stroke.

Toll-Like Receptor 4 Activation Contributes to Diabetic Bladder Dysfunction in a Murine Model of Type 1 Diabetes.

Diabetic bladder dysfunction (DBD) is a common urological complication of diabetes. Innate immune system activation via Toll-like receptor 4 (TLR4) leads to inflammation and oxidative stress and was implicated in diabetes pathophysiology. We hypothesized that bladder hypertrophy and hypercontractility in DBD is mediated by TLR4 activation. Wild-type (WT) and TLR4 knockout (TLR4KO) mice were made diabetic by streptozotocin (STZ) treatment, and bladder contractile function and TLR4 pathway expression were evaluated. Immunohistochemistry confirmed the expression of TLR4 in human and mouse bladder. Recombinant high-mobility group box protein 1 (HMGB1) increased bladder TLR4 and MyD88 expression and enhanced contractile response to electrical field stimulation. Bladder expression of TLR4 and MyD88 and serum expression of HMGB1 were increased in STZ compared with control mice. Carbachol (CCh)-mediated contraction was increased in bladders from STZ mice, and TLR4 inhibitor CLI-095 attenuated this increase. Induction of diabetes by STZ in WT mice increased bladder weight and contractile responses to CCh and to electrical field stimulation. TLR4KO mice were not protected from STZ-induced diabetes; however, despite levels of hyperglycemia similar to those of WT STZ mice, TLR4KO STZ mice were protected from diabetes-induced bladder hypertrophy and hypercontractility. These data suggest that TLR4 activation during diabetes mediates DBD-associated bladder hypertrophy and hypercontractility.

Erratum to: Primary glioblastoma multiforme tumors and recurrence: comparative analysis of the danger signals HMGB1, HSP70, and calreticulin

Purpose Glioblastoma multiforme (GBM) is the most common and aggressive brain tumor. Despite improved multimodal therapies, the tumor recurs in most cases. Diverging patient survival suggests great tumor heterogeneity and different therapy responses. Danger signals such as high-mobility group box protein 1 (HMGB1), heat shock protein 70 (HSP70), and calreticulin (CRT) are biomarker candidates, due to their association with tumor progression versus induction of antitumor immune responses. Overexpression of these danger signals has been reported for various types of tumors; however, their role in GBM is still elusive. A direct comparison of their expression in the primary tumor versus the corresponding relapse is still lacking for most tumor entities. Patients and methods We therefore performed an expression analysis by immunohistochemistry of the danger signals HMGB1, HSP70, and CRT in primary tumors and the corresponding relapses of 9 patients with de novo GBM. Results HMGB1 was highly expressed in primary tumors with a significant reduction in the respective relapse. The extracellular HSP70 expression was significantly increased in the relapse compared to the primary tumor. CRT was generally highly expressed in the primary tumor, with a slight increase in the relapse. Conclusion The combination of a decreased expression of HMGB1, an increased expression of extracellular HSP70, and an increased expression of CRT in the relapse seems to be beneficial for patient survival. HMGB1, extracellular HSP70, and CRT could be taken into concerted consideration as potential biomarkers for the prognosis of patients with GBM.

The Protective Role of Interleukin-33 in Myocardial Ischemia and Reperfusion Is Associated with Decreased HMGB1 Expression and Up-Regulation of the P38 MAPK Signaling Pathway.

Interleukin-33 (IL-33) plays a protective role in myocardial ischemia and reperfusion (I/R) injury, but the underlying mechanism was not fully elucidated. The present study was designed to investigate whether IL-33 protects against myocardial I/R injury by regulating both P38 mitogen-activated-protein kinase (P38 MAPK), which is involved in one of the downstream signaling pathways of IL-33, and high mobility group box protein 1 (HMGB1), a late pro-inflammatory cytokine. Myocardial I/R injury increased the level of IL-33 and its induced receptor (sST) in myocardial tissue. Compared with the I/R group, the IL-33 group had significantly lower cardiac injury (lower serum creatine kinase (CK), lactate dehydrogenase (LDH), and cTnI levels and myocardial infarct size), a suppressed inflammatory response in myocardial tissue (lower expression of HMGB1, IL-6, TNF-α and INF-γ) and less myocardial apoptosis (much higher Bcl-2/Bax ratio and lower cleaved caspase-3 expression). Moreover, IL-33 activated the P38 MAPK signaling pathway (up-regulating P-P38 expression) in myocardial tissue, and SB230580 partially attenuated the anti-inflammatory and anti-apoptosis effects of IL-33. These findings indicated that IL-33 protects against myocardial I/R injury by inhibiting inflammatory responses and myocardial apoptosis, which may be associated with the HMGB1 and P38 MAPK signaling pathways.

Expression of HMGB1 and NF-κB in Patients with Acute Leukemia and Its Significance

To explore the expression of high mobility group box protein 1 (HMGB1) and nuclear factor-kappa B (NF-κB) in patients with acute leukemia and its significance. 20 samples of bone marrow and peripheral blood from each acute leukemia groups (newly diagnozed, relapsed and complete remission groups) and 20 samples as control from patients with no-hematologic malignancies were collected. The expression level of HMGB1 in peripheral blood plasma was determined by ELISA; HMGB1 and NF-κB level in mononuclear cells were examined by RT-PCR. Western blot was used to determine HMGB1 and NF-κB protein levels. HMGB1 and NF-κB in bone marrow smears were determined by immnohistochemistry method (IHC). The expression level of HMGB1 obviously increased in patients of newly diagnosed and relapsed groups, as compared with control group there was statistical significance (P < 0.05), but there was no obvious difference in expression level of HMGB1 between complete remission group and control group (P > 0.05). The expression level of HMGB1 and NF-kB in monnuclear cells of bone marrow in newly-diagnosed group and relapsed group was significantly higher than that in control group (P < 0.05), but the expression levels of HMGB1 and NF-kB in complete remisson group did not change (P > 0.05). The results of immnohistochemistry method indicated that the possitive expression of HMGB1 and NF-kB maily was found in bone marrow smears of newly diagnosed and relapsed groups. HMGB1 is overexpressed in acute leukemia, which may be involved in the occurrence and development of acute leukemia by activating the NF-κB signaling pathway, HMGB1 may be a important index for observing therapeutic effectiveness and predicting recurrence of acute leukemia.

Instigation of endothelial Nlrp3 inflammasome by adipokine visfatin promotes inter-endothelial junction disruption: role of HMGB1.

Recent studies have indicated that the inflammasome plays a critical role in the pathogenesis of vascular diseases. However, the pathological relevance of this inflammasome activation, particularly in vascular cells, remains largely unknown. Here, we investigated the role of endothelial (Nucleotide-binding Oligomerization Domain) NOD-like receptor family pyrin domain containing three (Nlrp3) inflammasomes in modulating inter-endothelial junction proteins, which are associated with endothelial barrier dysfunction, an early onset of obesity-associated endothelial injury. Our findings demonstrate that the activation of Nlrp3 inflammasome by visfatin markedly decreased the expression of inter-endothelial junction proteins including tight junction proteins ZO-1, ZO-2 and occludin, and adherens junction protein VE-cadherin in cultured mouse vascular endothelial (VE) cell monolayers. Such visfatin-induced down-regulation of junction proteins in endothelial cells was attributed to high mobility group box protein 1 (HMGB1) release derived from endothelial inflammasome-dependent caspase-1 activity. Similarly, in the coronary arteries of wild-type mice, high-fat diet (HFD) treatment caused a down-regulation of inter-endothelial junction proteins ZO-1, ZO-2, occludin and VE-cadherin, which was accompanied with enhanced inflammasome activation and HMGB1 expression in the endothelium as well as transmigration of CD43(+) T cells into the coronary arterial wall. In contrast, all these HFD-induced alterations in coronary arteries were prevented in mice with Nlrp3 gene deletion. Taken together, these data strongly suggest that the activation of endothelial Nlrp3 inflammasomes as a result of the increased actions of injurious adipokines such as visfatin produces HMGB1, which act in paracrine or autocrine fashion to disrupt inter-endothelial junctions and increase paracellular permeability of the endothelium contributing to the early onset of endothelial injury during metabolic disorders such as obesity or high-fat/cholesterol diet.

The expression of high‐mobility group box protein‐1 in temporomandibular joint osteoarthritis with disc perforation

High-mobility group box protein-1 (HMGB-1), a potent promoter of inflammation, was believed to be a potential trigger of osteoarthritis (OA). Only a few studies have investigated the role of HMGB-1 in temporomandibular joint (TMJ) OA, especially in disc perforation cases. But in this study, not only the expression of HMGB-1 in TMJ OA with disc perforation was investigated but also the possible role of HMGB-1 in TMJ OA was discussed. Synovial membrane and disc specimens were collected from patients with TMJ OA, and the expression of HMGB-1 was detected using immunohistochemistry, real-time quantitative PCR and Western blotting. High-mobility group box protein-1 expressed strongly in cytoplasm and nucleus of lining layer cells and endothelial cells in osteoarthritic synovium. Staining of HMGB-1 was found intensive in the frontier tissue of the perforation in the perforated discs. HMGB-1 expression was also upregulated in osteoarthritic synovial cells and disc cells according to real-time quantitative PCR and Western blotting analysis. High-mobility group box protein-1 expression was upregulated in TMJ OA and might promote the progression of TMJ OA.

Role of high mobility group box protein 1 (HMGB1) in peripheral blood from patients with multiple sclerosis.

BackgroundHigh mobility group box protein 1 (HMGB1) is a transcriptional regulator that is receiving increasing attention in autoimmune disorders including multiple sclerosis (MS). Here, we investigated the role of HMGB1 in the peripheral blood compartment from MS patients.MethodsHMGB1 mRNA expression levels were determined by PCR in peripheral blood mononuclear cells (PBMC) of 29 healthy controls and 57 untreated MS patients (26 with relapsing-remitting MS - RRMS, 13 with secondary progressive MS - SPMS, and 18 with primary progressive MS - PPMS). HMGB1 protein levels were measured by ELISA in serum samples from 18 HC and 37 untreated MS patients (13 with RRMS, 14 with SPMS, and 10 with PPMS).ResultsHMGB1 expression levels were increased in PBMC from the whole MS group compared with controls (P = 0.03). Further stratification of the MS group revealed higher expression levels in PBMC from patients with relapse-onset MS, and differences were statistically significant for RRMS patients compared with PPMS patients and controls (P = 4 × 10−5 and P = 0.005, respectively) and also for SPMS patients compared with PPMS patients (P = 0.001). HMGB1 serum levels were increased in the whole MS group compared with controls (P = 2 × 10−4). In MS clinical forms, the highest HMGB1 serum levels were observed in RRMS patients, and differences were statistically significant compared to PPMS patients (P = 5 × 10−5), SPMS patients (P = 0.001), and controls (P = 0.001).ConclusionsThese results point to a role of HMGB1 mRNA and protein levels as disease activity biomarkers to discriminate the more inflammatory relapse-onset MS forms, particularly RRMS, from the less inflammatory PPMS form of the disease.Electronic supplementary materialThe online version of this article (doi:10.1186/s12974-015-0269-9) contains supplementary material, which is available to authorized users.

Analysis of the expression of HMGB-1, CXCL16, miRNA-30a, and TGF-β1 in primary nephritic syndrome patients and its significance.

We investigated the expression levels of high-mobility group box protein 1 (HMGB-1), CXC chemokine ligand 16 (CXCL16), microRNA (miRNA)-30a and transforming growth factor ß1 (TGF-ß1) in primary nephritic syndrome (PNS) patients and the clinical significance of this expression. A total of 56 patients with PNS were included in the PNS group, while 50 healthy subjects formed the normal control group. Serum levels of HMGB-1, CXCL16, miRNA-30a, and urinary TGF-ß1 concentrations were quantified along with other biochemical indices, including serum albumin, triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein, and urinary proteins. The correlation between levels of HMGB-1, CXCL16, miRNA-30a, and TGF-ß1 and biochemical indexes was further analyzed. PNS group patients had significantly higher levels of HMGB-1, CXCL16, miRNA- 30a, and TGF-ß1 compared to the control group (P < 0.05). PNS patients also had higher 24-h urinary protein, TG, TC, and LDL levels but lower serum albumin compared to subjects in the control group (P < 0.05). Serum HMGB-1, CXCL16, miRNA-30a, and urinary TGF-ß1 levels were all negatively correlated with serum albumin levels, but were positively correlated with TG, TC, LDL, and 24-h urinary protein (P < 0.05 in all cases). Additionally, a positive correlation existed among serum HMGB-1, CXCL16, miRNA-30a, and urinary TGF-ß1 levels (P < 0.01). HMGB-1, CXCL16, miRNA-30a, and urinary TGF-ß1 were highly expressed in PNS patients and may play important roles in the pathogenesis and development of PNS.

Expression of HMGB1 in the periodontal tissue subjected to orthodontic force application by Waldo's method in mice.

Recent studies indicate that high mobility group box protein 1 (HMGB1) originating from periodontal ligament (PDL) cells can be a potential regulator in the process of orthodontic tooth movement and periodontal tissue remodeling. The aim of this study is to investigate HMGB1 expression in periodontal tissue during orthodontic tooth movement in mice according to Waldo's method. Six 7-week-old C57BL6 mice were used in these experiments. The elastic band was inserted into the teeth space between the right first and second maxillary molars. After 3 days of mechanical loading, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the maxillary was extracted for histochemical analyses. The histological examination revealed local PDL tear at the tension side and the formation of extensive cell-free hyaline zones at the compression side. The immunolocalization of HMGB1 was significantly presented at tension side of PDL, apical area and dental pulp, whereas at the compression side of PDL, the labeling of HMGB1 was almost undetectable as the presence of hyaline zone. Taken together, we concluded that the orthodontic tooth movement by Waldo's method leads to histological changes and HMGB1 expression pattern that differ from those of coil spring method, including PDL tear and extensive hyaline zone which may severely destroy periodontal tissue and in turn impede tooth movement.

HMGB1 contributes to allergen-induced airway remodeling in a murine model of chronic asthma by modulating airway inflammation and activating lung fibroblasts.

The pro-inflammation factor high-mobility group box protein 1 (HMGB1) has been implicated in the pathogenesis of asthma. In this study, we used a murine model of chronic asthma to evaluate the effects of HMGB1 on airway remodeling. Female BALB/c mice were randomly divided into four groups: control, ovalbumin (OVA) asthmatic, OVA+isotype antibody and OVA+anti-HMGB1 antibody. Anti-HMGB1 antibody therapy was started on day 21 and was administered three times per week for 6 weeks before intranasal challenge with OVA. In this mouse model, HMGB1 expression is significantly elevated. The anti-HMGB1 antibody group exhibited decreased levels of immunoglobulin E (IgE) and inflammatory mediators and reduced inflammatory cell accumulation, airway hyperresponsiveness (AHR), mucus synthesis, smooth muscle thickness and lung collagen content compared with the OVA groups. Treatment with HMGB1 increased proliferation, migration, collagen secretion and α-smooth muscle actin (SMA) expression in MRC-5 cells. Treatment with the HMGB1/IL-1β complex significantly increased the expression and secretion of transforming growth factor (TGF-β1), matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF). Altogether, these results suggest that blocking HMGB1 activity may reverse airway remodeling by suppressing airway inflammation and modulating lung fibroblast phenotype and activation.