The role of HMGB1 in the pathogenesis of inflammatory and autoimmune diseases

Hepatoprotective effect of prenatal celecoxib in weaning preeclamptic rats: Role of HMGB1/MAPKs signaling

Preeclampsia (PE) is often associated with multiple organ damage that remains noticeable postnatally. Here, we tested the hypotheses that antenatal therapy with nonsteroidal antiinflammatory drugs (NSAIDs) refashions liver damage induced by PE in weaning rats and that the high mobility group box 1 (HMGB1) signaling modulates this interaction. PE was induced by pharmacologic nitric oxide deprivation during the last week of gestation (Nω-nitro-L-arginine methyl ester, L-NAME, 50 mg/kg/day, oral gavage). Compared with control rats, weaning PE rats revealed substantial rises in serum transaminases together with histopathological signs of hepatic cytoplasmic changes, portal inflammation, and central vein dilation. While gestational NSAIDs reversed the elevated transaminases, they had no effects (celecoxib, naproxen) or even worsened (diclofenac) the structural damage. Molecularly, celecoxib was the most effective NSAID in (i) reversing PE-evoked upregulation of hepatic HMGB1 gene expression and concomitant increments and decrements in mitogen-activated protein kinases MAPKERK and MAPKp38 expression, respectively, and (ii) elevating and suppressing serum interleukin-10 and tumor necrosis factor-α, respectively. Alternatively, rises in serum interleukin-1β and shifts in macrophage polarization towards an inflammatory phenotype caused by PE were comparably diminished by all NSAIDs. The data disclose an advantageous therapeutic potential for gestational celecoxib over diclofenac or naproxen in controlling hepatic dysfunction and HMGB1-interrelated inflammatory and oxidative sequels of PE.

Ecliptasaponin A protects heart against acute ischemia-induced myocardial injury by inhibition of the HMGB1/TLR4/NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Eclipta prostrata (Linn.) is a traditional medicinal Chinese herb that displays multiple biological activities, such as encompassing immunomodulatory, anti-inflammatory, anti-tumor, liver-protective, antioxidant, and lipid-lowering effects. Ecliptasaponin A (ESA), a pentacyclic triterpenoid saponin isolated from Eclipta prostrata (Linn.), has been demonstrated to exert superior anti-inflammatory activity against many inflammatory disorders.

AIM OF THE STUDY

Inflammation plays a critical role in acute myocardial infarction (AMI). This study aims to explore the treatment effects of ESA in AMI, as well as the underlying mechanism.

METHODS

An AMI mouse model was established in mice via left anterior descending coronary artery (LAD) ligation. After surgery, ESA was injected at doses of 0.5, 1.25, and 2.5 mg/kg, respectively. Myocardial infarction size, cardiomyocyte apoptosis and cardiac echocardiography were studied. The potential mechanism of action of ESA was investigated by RNA-seq, Western blot, surface plasmon resonance (SPR), molecular docking, and immunofluorescence staining.

RESULTS

ESA treatment not only significantly reduced myocardial infarct size, decreased myocardial cell apoptosis, and inhibited inflammatory cell infiltration, but also facilitated to improve cardiac function. RNA-seq and Western blot analysis proved that ESA treatment-induced differential expression genes mainly enriched in HMGB1/TLR4/NF-κB pathway. Consistently, ESA treatment resulted into the down-regulation of IL-1β, IL-6, and TNF-α levels after AMI. Furthermore, SPR and molecular docking results showed that ESA could bind directly to HMGB1, thereby impeding the activation of the downstream TLR4/NF-κB pathway. The immunofluorescence staining and Western blot results at the cellular level also demonstrated that ESA inhibited the activation of the HMGB1/TLR4/NF-κB pathway in H9C2 cells.

CONCLUSION

Our study was the first to demonstrate a cardiac protective role of ESA in AMI. Mechanism study indicated that the treatment effects of ESA are mainly attributed to its anti-inflammatory activity that was mediated by the HMGB1/TLR4/NF-κB pathway.

Associations of insulin sensitivity and immune inflammatory responses with child blood lead (Pb) and PM2.5 exposure at an e-waste recycling area during the COVID-19 lockdown

Fine particular matter (PM2.5) and lead (Pb) exposure can induce insulin resistance, elevating the likelihood of diabetes onset. Nonetheless, the underlying mechanism remains ambiguous. Consequently, we assessed the association of PM2.5 and Pb exposure with insulin resistance and inflammation biomarkers in children. A total of 235 children aged 3-7 years in a kindergarten in e-waste recycling areas were enrolled before and during the Corona Virus Disease 2019 (COVID-19) lockdown. Daily PM2.5 data was collected and used to calculate the individual PM2.5 daily exposure dose (DED-PM2.5). Concentrations of whole blood Pb, fasting blood glucose, serum insulin, and high mobility group box 1 (HMGB1) in serum were measured. Compared with that before COVID-19, the COVID-19 lockdown group had lower DED-PM2.5 and blood Pb, higher serum HMGB1, and lower blood glucose and homeostasis model assessment of insulin resistance (HOMA-IR) index. Decreased DED-PM2.5 and blood Pb levels were linked to decreased levels of fasting blood glucose and increased serum HMGB1 in all children. Increased serum HMGB1 levels were linked to reduced levels of blood glucose and HOMA-IR. Due to the implementation of COVID-19 prevention and control measures, e-waste dismantling activities and exposure levels of PM2.5 and Pb declined, which probably reduced the association of PM2.5 and Pb on insulin sensitivity and diabetes risk, but a high level of risk of chronic low-grade inflammation remained. Our findings add new evidence for the associations among PM2.5 and Pb exposure, systemic inflammation and insulin resistance, which could be a possible explanation for diabetes related to environmental exposure.

The impact of cytokines in neuroinflammation-mediated stroke

Cerebral stroke is ranked as the third most common contributor to global mortality and disability. The involvement of inflammatory mechanisms, both peripherally and within the CNS, holds significance in the pathophysiological cascades following the initiation of stroke. After the onset of acute stroke, predominantly ischemic, a subsequent phase of neuroinflammation ensues. It is a dual-effect process that not only exacerbates injury, leading to cell death, but paradoxically, it also serves a shielding role in facilitating recovery. Cytokines serve as pivotal mediators within the inflammatory cascade, actively contributing to the progression of ischemic damage. Stroke is followed by increased expression of pro-inflammatory cytokines including TNF-α, IL-1β, IL-6, etc. leading to the recruitment and stimulation of glial cells and peripheral leukocytes at the site of injury, promoting neuroinflammation. Cytokines can directly induce neuronal injury and death through various mechanisms, including excitotoxicity, oxidative stress, HPA-axis activation, secretion of matrix metalloproteinase and apoptosis. They can also amplify the inflammatory response, leading to further neuronal damage. Therapeutic strategies aimed at modulating cytokine release, immune response and cytokine signalling or activity are being explored as potential interventions to mitigate neuroinflammation and its detrimental effects in stroke. In this review, we have given a concise summary of our current knowledge of the function of various cytokines, brain inflammation and various signalling and molecular pathways including JAK/STAT3, TGF-β/Smad, MAPK, HMGB1/TLR and NF-κB modulated cytokines regulation in stroke. Therapeutic agents such as MCC950, genistein, edaravone, minocycline, etc. targeting various cytokines-associated signalling pathways have shown efficacy in preclinical and clinical trials reducing the pathophysiology of the illness were also addressed in this study.

Microglial MyD88-dependent pathways are regulated in a sex-specific manner in the context of HMGB1-induced anxiety

Chronic stress is a significant risk factor for the development and recurrence of anxiety disorders. Chronic stress impacts the immune system, causing microglial functional alterations in the medial prefrontal cortex (mPFC), a brain region involved in the pathogenesis of anxiety. High mobility group box 1 protein (HMGB1) is an established modulator of neuronal firing and a potent pro-inflammatory stimulus released from neuronal and non-neuronal cells following stress. HMGB1, in the context of stress, acts as a danger-associated molecular pattern (DAMP), instigating robust proinflammatory responses throughout the brain, so much so that localized drug delivery of HMGB1 alters behavior in the absence of any other forms of stress, i.e., social isolation, or behavioral stress models. Few studies have investigated the molecular mechanisms that underlie HMGB1-associated behavioral effects in a cell-specific manner. The aim of this study is to investigate cellular and molecular mechanisms underlying HMGB1-induced behavioral dysfunction with regard to cell-type specificity and potential sex differences. Here, we report that both male and female mice exhibited anxiety-like behavior following increased HMGB1 in the mPFC as well as changes in microglial morphology. Interestingly, our results demonstrate that HMGB1-induced anxiety may be mediated by distinct microglial MyD88-dependent mechanisms in females compared to males. This study supports the hypothesis that MyD88 signaling in microglia may be a crucial mediator of the stress response in adult female mice.

Circulating Nucleosomes as a Novel Biomarker for Sepsis: A Scoping Review

Circulating nucleosome levels are commonly elevated in physiological and pathological conditions. Their potential as biomarkers for diagnosing and prognosticating sepsis remains uncertain due, in part, to technical limitations in existing detection methods. This scoping review explores the possible role of nucleosome concentrations in the diagnosis, prognosis, and therapeutic management of sepsis. A comprehensive literature search of the Cochrane and Medline libraries from 1996 to 1 February 2024 identified 110 potentially eligible studies, of which 19 met the inclusion criteria, encompassing a total of 39 SIRS patients, 893 sepsis patients, 280 septic shock patients, 117 other ICU control patients, and 345 healthy volunteers. The enzyme-linked immunosorbent assay [ELISA] was the primary method of nucleosome measurement. Studies consistently reported significant correlations between nucleosome levels and other NET biomarkers. Nucleosome levels were higher in patients with sepsis than in healthy volunteers and associated with disease severity, as indicated by SOFA and APACHE II scores. Non-survivors had higher nucleosome levels than survivors. Circulating nucleosome levels, therefore, show promise as early markers of NETosis in sepsis, with moderate diagnostic accuracy and strong correlations with disease severity and prognosis. However, the available evidence is drawn mainly from single-center, observational studies with small sample sizes and varied detection methods, warranting further investigation.

A Long-Retention Cell Membrane-Targeting AIEgen for Boosting Tumor Theranostics

Designing and developing photosensitizers with cell membrane specificity is crucial for achieving effective multimodal therapy of tumors compared to other organelles. Here, we designed and screened a photosensitizer CM34 through donor/receptor regulation strategies, and it is able to achieve long-retention cell membrane targeting. It is not only an extremely excellent cell membrane targeted tumor theranostic agent, but also found to be a promising potential immune activator. Specifically, CM34 with a larger intramolecular twist angle is more likely to form larger aggregates in aqueous solutions, and the introduction of cyanide group also enhances its interaction with cell membranes, which were key factors hindering molecular penetration of the cell membrane and prolonging its residence time on the cell membrane, providing conditions for further membrane targeted photodynamic therapy. Furthermore, the efflux of contents caused by cell necrosis directly activates the immune response. In summary, this study realizes to clarify and refine all potential mechanisms of action through density functional theory calculations, photophysical property measurements, and cellular level mechanism exploration, providing a new direction for the clinical development of cell membrane targeted anti-tumor immune activators.

Immuno-Microbial Signature of Vaccine-Induced Immunity against SARS-CoV-2

Although vaccines address critical public health needs, inter-individual differences in responses are not always considered in their development. Understanding the underlying basis for these differences is needed to optimize vaccine effectiveness and ultimately improve disease control. In this pilot study, pre- and post-antiviral immunological and gut microbiota features were characterized to examine inter-individual differences in SARS-CoV-2 mRNA vaccine response. Blood and stool samples were collected before administration of the vaccine and at 2-to-4-week intervals after the first dose. A cohort of 14 adults was separated post hoc into two groups based on neutralizing antibody levels (high [HN] or low [LN]) at 10 weeks following vaccination. Bivariate correlation analysis was performed to examine associations between gut microbiota, inflammation, and neutralization capacity at that timepoint. These analyses revealed significant differences in gut microbiome composition and inflammation states pre-vaccination, which predicted later viral neutralization capacity, with certain bacterial taxa, such as those in the genus Prevotella, found at higher abundance in the LN vs HN group that were also negatively correlated with a panel of inflammatory factors such as IL-17, yet positively correlated with plasma levels of the high mobility group box 1 (HMGB-1) protein at pre-vaccination. In particular, we observed a significant inverse relationship (Pearson = -0.54, p = 0.03) between HMGB-1 pre-vaccination and neutralization capacity at 10 weeks post-vaccination. Consistent with known roles as mediators of inflammation, our results altogether implicate HMGB-1 and related gut microbial signatures as potential biomarkers in predicting SARS-CoV-2 mRNA vaccine effectiveness measured by the production of viral neutralization antibodies.

High mobility group box 1 mediates inflammatory responses in malignant peritoneal mesothelioma

BACKGROUND

Serum high mobility group box 1 (HMGB1) serves as a diagnostic biomarker for malignant peritoneal mesothelioma (MPM) patients, yet its diagnostic significance within MPM tumor tissues remains uncertain. This study aims to elucidate the roles of HMGB1 in MPM.

METHODS

HMGB1 expression analysis was conducted in both tumor and adjacent non-cancerous tissues collected from MPM patients. The two-year follow-up of MPM patients commenced from the diagnosis date. Inflammatory cytokine analysis was performed on these tissues, and Pearson correlation coefficient analysis was applied to examine variable relationships. In vitro assays included constructing an HMGB1 knockdown cell line, assessing cell viability, apoptosis, and inflammatory cytokine levels to delineate HMGB1's roles in MPM.

RESULTS

HMGB1 overexpression was observed in MPM tumor tissues, particularly in stages III-IV. Diagnostic implications of HMGB1 for MPM were evident, augmenting its diagnostic value. HMGB1 overexpression correlated with diminished survival rates. Positive correlations existed between inflammatory cytokines and HMGB1 in MPM tumor tissues and cell lines. Suppression of HMGB1 regulated cell growth and apoptosis in MPM cell lines.

CONCLUSION

HMGB1 exhibits diagnostic potential for MPM and modulates inflammatory responses within the disease context.

Deletion of Glyoxalase 1 Exacerbates Acetaminophen-Induced Hepatotoxicity in Mice

Acetaminophen (APAP) overdose triggers a cascade of intracellular oxidative stress events, culminating in acute liver injury. The clinically used antidote, N-acetylcysteine (NAC), has a narrow therapeutic window, and early treatment is essential for a satisfactory therapeutic outcome. For more versatile therapies that can be effective even at late presentation, the intricacies of APAP-induced hepatotoxicity must be better understood. Accumulation of advanced glycation end products (AGEs) and the consequent activation of the receptor for AGEs (RAGE) are considered one of the key mechanistic features of APAP toxicity. Glyoxalase 1 (Glo-1) regulates AGE formation by limiting the levels of methylglyoxal (MEG). In this study, we studied the relevance of Glo-1 in the APAP-mediated activation of RAGE and downstream cell death cascades. Constitutive Glo-1-knockout mice (GKO) and a cofactor of Glo-1, ψ-GSH, were used as tools. Our findings showed elevated oxidative stress resulting from the activation of RAGE and hepatocyte necrosis through steatosis in GKO mice treated with high-dose APAP compared to wild-type controls. A unique feature of the hepatic necrosis in GKO mice was the appearance of microvesicular steatosis as a result of centrilobular necrosis, rather than the inflammation seen in the wild type. The GSH surrogate and general antioxidant ψ-GSH alleviated APAP toxicity irrespective of the Glo-1 status, suggesting that oxidative stress is the primary driver of APAP toxicity. Overall, the exacerbation of APAP hepatotoxicity in GKO mice suggests the importance of this enzyme system in antioxidant defense against the initial stages of APAP overdose.

Positive impacts of Nannochloropsis oculata supplementation on gene expression of immune and antioxidant markers and metabolic profile of Barki sheep in the transition period and lipogenic effects on progeny

Nannochloropsis species should be given priority when it comes to microalgae that should be added to feed since they are suitable for intense culture and have a high concentration of PUFAs (especially EPA), antioxidants, and certain vitamins. This study investigated the possible immune and antioxidant impacts of Nannochloropsis supplementation on Barki ewes during transition period and their newly born lambs. Three weeks prior to the expected time of lambing, the researched ewes were divided into two equal groups of thirty ewes each. The second group, on the other hand, was fed the same base diet as the first group plus 10 g of commercially available Nannochloropsis powder per kg of concentrate, given daily to each ewe's concentrate. Findings revealed that supplementation of ewes with Nannochloropsis significantly up-regulated the expression pattern of immune (NFKB, RANTES, HMGB1, TNF-α, IRF4, TLR7, CLA-DRB3.2, IL1B, IL6, CXCL8, S-LZ, and Cathelicidin), and antioxidant (SOD1, CAT, GPX1, GST, ATOX1, Nrf2 and AhpC/TSA) markers in ewes post-lambing and their newly born lambs. Additionally, mRNA levels of lipogenic (ACACA, FASN SCD, LPL, and BTN1A) markers were significantly up-regulated in lambs from supplemented ewes than control ones. There was a significant increase in the WBCs, Hb, RBc count, serum level of glucose, total protein, triacylglycerol and total cholesterol, GPx, catalase, IL1α and IL6 with significantly decreased serum level of TNF-α and MDA in supplemented ewes after lambing as compared with control ones. There was also a significant increase in WBCs, Hb, RBc count, birth weight and body temperature with significantly decreased in the serum levels of TNF-α and stillbirth of newly born lambs from supplemented ewes as compared to other lambs from control ones.

Mechanistic insight on the role of iRhom2-TNF-α-BAFF signaling pathway in various autoimmune disorders

iRhom2 is a crucial cofactor involved in upregulation of TNF receptors (TNFRs) and the pro-inflammatory cytokine tumor necrosis factor (TNF-) from the cell surface by ADAM17. Tumor necrosis factor- α converting enzyme (TACE) is another name given to ADAM17. Many membrane attached biologically active molecules are cleaved by this enzyme which includes TNFRs and the pro-inflammatory cytokine tumor necrosis factor- α. The TNF receptors are of two types TNFR1 and TNFR2. iRhom2 belongs to the pseudo-protease class of rhomboid family, its abundance is observed in the immune cells. Biological activity of ADAM17 is affected in multiple levels by the iRhom2. ADAM17 is trafficked into the Golgi apparatus by the action of iRhom2, where it gets matured proteolytically and is stimulated to perform its function on the cell surface. This process of activation of ADAM17 results in the protection of the organism from the cascade of inflammatory reactions, as this activation blocks the TNF- α mediated secretion responsible for inflammatory responses produced. Present paper illustrates about the iRhom2-TNF-α-BAFF signaling pathway and its correlation with several autoimmune disorders such as Rheumatoid Arthritis, Systemic Lupus Erythematosus, Hemophilia Arthropathy, Alzheimer's disease and Tylosis with esophageal cancer etc.

Group XIV C-type lectins: emerging targets in tumor angiogenesis

C-type lectins, distinguished by a C-type lectin binding domain (CTLD), are an evolutionarily conserved superfamily of glycoproteins that are implicated in a broad range of physiologic processes. The group XIV subfamily of CTLDs are comprised of CD93, CD248/endosialin, CLEC14a, and thrombomodulin/CD141, and have important roles in creating and maintaining blood vessels, organizing extracellular matrix, and balancing pro- and anti-coagulative processes. As such, dysregulation in the expression and downstream signaling pathways of these proteins often lead to clinically relevant pathology. Recently, group XIV CTLDs have been shown to play significant roles in cancer progression, namely tumor angiogenesis and metastatic dissemination. Interest in therapeutically targeting tumor vasculature is increasing and the search for novel angiogenic targets is ongoing. Group XIV CTLDs have emerged as key moderators of tumor angiogenesis and metastasis, thus offering substantial therapeutic promise for the clinic. Herein, we review our current knowledge of group XIV CTLDs, discuss each's role in malignancy and associated potential therapeutic avenues, briefly discuss group XIV CTLDs in the context of two other relevant lectin families, and offer future direction in further elucidating mechanisms by which these proteins function and facilitate tumor growth.

Role and uptake of metal-based nanoconstructs as targeted therapeutic carriers for rheumatoid arthritis

Rheumatoid Arthritis (RA) is a chronic autoimmune systemic inflammatory disease that affects the joints and other vital organs and diminishes the quality of life. The current developments and innovative treatment options have significantly slowed disease progression and improved their quality of life. Medicaments can be delivered to the inflamed synovium via nanoparticle systems, minimizing systemic and undesirable side effects. Numerous nanoparticles such as polymeric, liposomal, and metallic nanoparticles reported are impending as a good carrier with therapeutic properties. Other issues to be considered along are nontoxicity, nanosize, charge, optical property, and ease of high surface functionalization that make them suitable carriers for drug delivery. Metallic nanoparticles (MNPs) (such as silver, gold, zinc, iron, titanium oxide, and selenium) not only act as good carrier with desired optical property, and high surface modification ability but also have their own therapeutical potential such as anti-oxidant, anti-inflammatory, and anti-arthritic properties, making them one of the most promising options for RA treatment. Regardless, cellular uptake of MNPs is one of the most significant criterions for targeting the medication. This paper discusses the numerous interactions of nanoparticles with cells, as well as cellular uptake of NPs. This review provides the mechanistic overview on MNPs involved in RA therapies and regulation anti-arthritis response such as ability to reduce oxidative stress, suppressing the release of proinflammatory cytokines and expression of LPS induced COX-2, and modulation of MAPK and PI3K pathways in Kuppfer cells and hepatic stellate cells. Despite of that MNPs have also ability to regulates enzymes like glutathione peroxidases (GPxs), thioredoxin reductases (TrxRs) and act as an anti-inflammatory agent.

Adjunctive treatments for pneumococcal meningitis: a systematic review of experimental animal models

New treatments are needed to improve the prognosis of pneumococcal meningitis. We performed a systematic review on adjunctive treatments in animal models of pneumococcal meningitis in order to identify treatments with the most potential to progress to clinical trials. Studies testing therapy adjunctive to antibiotics in animal models of pneumococcal meningitis were included. A literature search was performed using Medline, Embase and Scopus for studies published from 1990 up to 17 February 2023. Two investigators screened studies for inclusion and independently extracted data. Treatment effect was assessed on the clinical parameters disease severity, hearing loss and cognitive impairment and the biological parameters inflammation, brain injury and bacterial load. Adjunctive treatments were evaluated by their effect on these outcomes and the quality, number and size of studies that investigated the treatments. Risk of bias was assessed with the SYRCLE risk of bias tool. A total of 58 of 2462 identified studies were included, which used 2703 experimental animals. Disease modelling was performed in rats (29 studies), rabbits (13 studies), mice (12 studies), gerbils (3 studies) or both rats and mice (1 study). Meningitis was induced by injection of Streptococcus pneumoniae into the subarachnoid space. Randomization of experimental groups was performed in 37 of 58 studies (64%) and 12 studies (12%) were investigator-blinded. Overall, 54 treatment regimens using 46 adjunctive drugs were evaluated: most commonly dexamethasone (16 studies), daptomycin (5 studies), complement component 5 (C5; 3 studies) antibody and Mn(III)tetrakis(4-benzoicacid)porphyrin chloride (MnTBAP; 3 studies). The most frequently evaluated outcome parameters were inflammation [32 studies (55%)] and brain injury [32 studies (55%)], followed by disease severity [30 studies (52%)], hearing loss [24 studies (41%)], bacterial load [18 studies (31%)] and cognitive impairment [9 studies (16%)]. Adjunctive therapy that improved clinical outcomes in multiple studies was dexamethasone (6 studies), C5 antibodies (3 studies) and daptomycin (3 studies). HMGB1 inhibitors, matrix metalloproteinase inhibitors, neurotrophins, antioxidants and paquinimod also improved clinical parameters but only in single or small studies. Evaluating the treatment effect of adjunctive therapy was complicated by study heterogeneity regarding the animal models used and outcomes reported. In conclusion, 24 of 54 treatment regimens (44%) tested improved clinically relevant outcomes in experimental pneumococcal meningitis but few were tested in multiple well-designed studies. The most promising new adjunctive treatments are with C5 antibodies or daptomycin, suggesting that these drugs could be tested in clinical trials.

Investigating HMGB1 as a potential serum biomarker for early diabetic nephropathy monitoring by quantitative proteomics

Current diagnostic methods for diabetic nephropathy (DN) lack precision, especially in early stages and monitoring progression. This study aims to find potential biomarkers for DN progression and evaluate their accuracy. Using serum samples from healthy controls (NC), diabetic patients (DM), early-medium stage DN (DN-EM), and late-stage DN (DN-L), researchers employed quantitative proteomics and Mfuzz clustering analysis revealed 15 proteins showing increased expression during DN progression, hinting at their biomarker potential. Combining Mfuzz clustering with weighted gene co-expression network analysis (WGCNA) highlighted five candidates (HMGB1, CD44, FBLN1, PTPRG, and ADAMTSL4). HMGB1 emerged as a promising biomarker, closely correlated with renal function changes. Experimental validation supported HMGB1's upregulation under high glucose conditions, reinforcing its potential as an early detection biomarker for DN. This research advances DN understanding and identifies five potential biomarkers, notably HMGB1, as a promising early monitoring target. These findings set the stage for future clinical diagnostic applications in DN.

High mobility group box 1 promotes endometriosis under hypoxia by regulating inflammation and autophagy in vitro and in vivo

BACKGROUND

Endometriosis is a chronic disease. Our previous study identified a positive correlation between high mobility group box 1 (HMGB1) and endometriosis, and HMGB1 and inflammation. However, the precise roles of HMGB1 in endometriosis are not fully elucidated.

METHODS

We overexpressed HMGB1 in human endometrial stromal cells (HESCs). The expression of pro-inflammatory cytokines and autophagy-related markers were detected by Western blot and ELISA. We generated HMGB1 deficient mice and established the murine model of endometriosis. The development of endometriosis was evaluated. The expression of cytokines and markers of autophagy in implant lesions and mouse endometrial stromal cells was measured.

RESULTS

Overexpression of HMGB1 in HESCs promoted the pro-inflammatory cytokines production and expression of autophagy-related markers. HMGB1 deficient mice had less implant lesions, decreased inflammatory cytokines level and down-regulated autophagy-related markers in implant lesions and mouse endometrial stromal cells.

CONCLUSION

HMGB1 promotes endometriosis by regulating inflammation and autophagy.

Age-Dependent and Aβ-Induced Dynamic Changes in the Subcellular Localization of HMGB1 in Neurons and Microglia in the Brains of an Animal Model of Alzheimer's Disease

HMGB1 is a prototypical danger-associated molecular pattern (DAMP) molecule that co-localizes with amyloid beta (Aβ) in the brains of patients with Alzheimer's disease. HMGB1 levels are significantly higher in the cerebrospinal fluid of patients. However, the cellular and subcellular distribution of HMGB1 in relation to the pathology of Alzheimer's disease has not yet been studied in detail. Here, we investigated whether HMGB1 protein levels in brain tissue homogenates (frontal cortex and striatum) and sera from Tg-APP/PS1 mice, along with its cellular and subcellular localization in those regions, differed. Total HMGB1 levels were increased in the frontal cortices of aged wildtype (7.5 M) mice compared to young (3.5 M) mice, whereas total HMGB1 levels in the frontal cortices of Tg-APP/PS1 mice (7.5 M) were significantly lower than those in age-matched wildtype mice. In contrast, total serum HMGB1 levels were enhanced in aged wildtype (7.5 M) mice and Tg-APP/PS1 mice (7.5 M). Further analysis indicated that nuclear HMGB1 levels in the frontal cortices of Tg-APP/PS1 mice were significantly reduced compared to those in age-matched wildtype controls, and cytosolic HMGB1 levels were also significantly decreased. Triple-fluorescence immunohistochemical analysis indicated that HMGB1 appeared as a ring shape in the cytoplasm of most neurons and microglia in the frontal cortices of 9.5 M Tg-APP/PS1 mice, indicating that nuclear HMGB1 is reduced by aging and in Tg-APP/PS1 mice. Consistent with these observations, Aβ treatment of both primary cortical neuron and primary microglial cultures increased HMGB1 secretion in the media, in an Aβ-dose-dependent manner. Our results indicate that nuclear HMGB1 might be translocated from the nucleus to the cytoplasm in both neurons and microglia in the brains of Tg-APP/PS1 mice, and that it may subsequently be secreted extracellularly.

Xiaobanxia decoction alleviates chemotherapy-induced nausea and vomiting by inhibiting GSDME-mediated pyroptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaobanxia Decoction (XBXD), a traditional antiemetic formula, is effective in preventing chemotherapy-induced nausea and vomiting (CINV), but its underlying mechanism has not been fully clarified.

AIM OF THE STUDY

To investigate whether the antiemetic mechanisms of XBXD against CINV is associated with the reduction of GSDME-mediated pyroptosis and the alleviation of gastrointestinal inflammation induced by cisplatin.

MATERIALS AND METHODS

We established the in vivo pica rat model and the in vitro small intestinal epithelial cell (IEC-6 cell) injury model by cisplatin challenge. The levels of ROS, IL-1β, IL-18, HMGB1 were measured by ELISA. The histopathological changes of gastrointestinal (GI) tissues were examined by HE staining. The expression and localization of GSDME in GI tissues were determined by IHC. The GSDME mRNA expression in GI tissues was determined by RT-PCR. The IEC-6 cell viability was detected by CCK-8. The morphology of IEC-6 cells was observed by optical microscope and scanning electron microscopy. Pyroptosis was examined using Hoechst33342/PI staining. The intracellular ROS levels were measured with the fluorescent probe DCFH-DA. The expression levels of JNK, p-JNK, Bax, Bcl-2, caspase-9, caspase-3 and GSDME in GI tissues and IEC-6 cells were determined by WB.

RESULTS

We found that the cumulative kaolin intake (pica behavior, analogous to emesis) significantly increased in cisplatin-treated rats, accompanied by significant inflammatory pathological changes of GI tissues. XBXD decreased the cumulative kaolin intake and alleviated GI inflammation in cisplatin-treated rats by inhibiting the activation of the ROS/JNK/Bax signaling pathway and by reducing GSDME-mediated pyroptosis. Additionally, cisplatin damaged IEC-6 cells by activating GSDME-dependent pyroptosis. XBXD reduced GSDME-mediated IEC-6 cell pyroptotic death by regulating the ROS/JNK/Bax signaling pathway.

CONCLUSIONS

This study suggested that GSDME-mediated pyroptosis greatly contributes to the occurrence of CINV, and suppressing GSDME-mediated pyroptosis is the important antiemetic mechanism of XBXD.

Green Extracts with Metal-based Nanoparticles for Treating Inflammatory Diseases: A Review

Globally, high death rates and poor quality of life are caused mainly by inflammatory diseases. Corticosteroids, which may have systemic side effects and would enhance the risk of infection, are the common forms of therapy. The field of nanomedicine has created composite nanoparticles that carry a pharmacological carrier and target ligands for distribution to sites of inflammation with less systemic toxicity. However, their relatively large size often causes systemic clearance. An interesting approach is metal-based nanoparticles that naturally reduce inflammation. They are made not only to be small enough to pass through biological barriers but also to allow label-free monitoring of their interactions with cells. The following literature review discusses the mechanistic analysis of the anti-inflammatory properties of several metal-based nanoparticles, including gold, silver, titanium dioxide, selenium, and zinc oxide. Current research focuses on the mechanisms by which nanoparticles infiltrate cells and the anti-inflammatory techniques using herbal extracts-based nanoparticles. Additionally, it provides a brief overview of the literature on many environmentally friendly sources employed in nanoparticle production and the mechanisms of action of various nanoparticles.

Deletion of Glyoxalase 1 exacerbates acetaminophen-induced hepatotoxicity in mice

Acetaminophen (APAP) overdose triggers a cascade of intracellular oxidative stress events culminating in acute liver injury. The clinically used antidote, N-acetylcysteine (NAC) has a narrow therapeutic window and early treatment is essential for satisfactory therapeutic outcome. For more versatile therapies that can be effective even at late-presentation, the intricacies of APAP-induced hepatotoxicity must be better understood. Accumulation of advanced glycation end-products (AGEs) and consequent activation of the receptor for AGEs (RAGE) are considered one of the key mechanistic features of APAP toxicity. Glyoxalase-1 (Glo-1) regulates AGE formation by limiting the levels of methylglyoxal (MEG). In this study, we studied the relevance of Glo-1 in APAP mediated activation of RAGE and downstream cell-death cascades. Constitutive Glo-1 knockout mice (GKO) and a cofactor of Glo-1, ψ-GSH, were employed as tools. Our findings show elevated oxidative stress, activation of RAGE and hepatocyte necrosis through steatosis in GKO mice treated with high-dose APAP compared to wild type controls. A unique feature of the hepatic necrosis in GKO mice is the appearance of microvesicular steatosis as a result of centrilobular necrosis, rather than inflammation seen in wild type. The GSH surrogate and general antioxidant, ψ-GSH alleviated APAP toxicity irrespective of Glo-1 status, suggesting that oxidative stress being the primary driver of APAP toxicity. Overall, exacerbation of APAP hepatotoxicity in GKO mice suggests the importance of this enzyme system in antioxidant defense against initial stages of APAP overdose.

Mitigating Scar Tissue Formation in Tendon Injuries: Targeting HMGB1, AMPK Activation, and Myofibroblast Migration All at Once

Tendon injuries, while prevalent, present significant challenges regarding their structural and functional restoration. Utilizing alpha-smooth muscle actin (α-SMA)-Ai9-scleraxis (Scx)-green fluorescent protein (GFP) transgenic mice, which exhibit both Scx (a tendon cell marker) and α-SMA (a myofibroblast marker), we explored the effects of metformin (Met) on tendon healing, repair, and its mechanisms of action. Our findings revealed that intraperitoneal (IP) injections of Met, administered before or after injury, as well as both, effectively prevented the release of HMGB1 into the tendon matrix and reduced circulating levels of HMGB1. Additionally, Met treatment increased and activated AMPK and suppressed TGF-β1 levels within the healing tendon. Tendon healing was also improved by blocking the migration of α-SMA+ myofibroblasts, reducing the prevalence of disorganized collagen fibers and collagen type III. It also enhanced the presence of collagen type I. These outcomes highlight Met's anti-fibrotic properties in acutely injured tendons and suggest its potential for repurposing as a therapeutic agent to minimize scar tissue formation in tendon injuries, which could have profound implications in clinical practice.

Polyautoimmunity in patients with cutaneous lupus erythematosus: A nationwide sex- and age-matched cohort study from Denmark

Background

Polyautoimmunity is defined as having 2 or more autoimmune diseases. Little is known about polyautoimmunity in patients with cutaneous lupus erythematosus (CLE).

Objectives

To estimate prevalence and 5-year incidence of non-lupus erythematosus (LE) autoimmune diseases in patients with CLE.

Methods

Patients with CLE were identified In the Danish National Patient Registry and each patient was age- and sex-matched with 10 general population controls. Outcome information on non-LE autoimmune diseases was obtained by register-linkage between Danish National Patient Registry and the National Prescription Register. The risk ratio (RR) for prevalent non-LE autoimmune disease at time of CLE diagnosis was calculated in modified Poisson regression; and hazard ratios (HRs) for incident non-LE autoimmune disease were estimated in Cox regression analyses.

Results

Overall, 1674 patients with CLE had a higher prevalence of a non-LE autoimmune disease than the comparators (18.5 vs 7.9%; RR 2.4; 95% CI, 2.1 to 2.6). Correspondingly, the cumulative incidence of a non-LE autoimmune disease during 5 years of follow-up was increased for the patients with CLE: HR 3.5 (95% CI, 3.0 to 4.0).

Limitations

Risk of detection and misclassification bias, mainly pertaining to the CLE group.

Conclusion

Patients with CLE had higher prevalence and 5-year cumulative incidence of a non-LE autoimmune disease than the general population.

Topically applied pH-responsive nanogels for alkyl radical-based therapy against psoriasiform hyperplasia

Phototherapy is a conventional antipsoriatic approach based on oxygen-relevant generation of oxidative stress to inhibit keratinocyte hyperproliferation. However, this therapy can be restricted due to local hypoxia in psoriatic lesions. The generation of alkyl radicals is oxygen-independent and suppresses hyperproliferation. Herein, we established alkyl radical-based therapy to treat psoriatic hyperplasia. Because alkyl radicals are short-lived compounds, we loaded 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (AIPH) as a precursor of alkyl radicals into the chitosan nanogels to improve stability. The present study presented a topically applied nanogel that led to a pH-responsive network sensitive to skin pH. This pH responsiveness of the nanogels allowed fast alkyl radical release in the target site. The physicochemical properties of the prepared nanogels were determined through size, zeta potential, scanning electron microscopy, and absorption spectroscopy. The antipsoriatic activity was examined with keratinocyte- and animal-based studies. The nanogels displayed a smooth and spherical morphology with a hydrodynamic diameter of 215 nm. This size was largely increased as the environmental pH increased to 6. The nanogels heated at 44 °C produced alkyl radicals to induce keratinocyte death through the necrosis pathway. Bioimaging demonstrated that topically applied nanogels could deliver alkyl radicals into the epidermis. This targeting was accompanied by the accumulation of free radicals in the epidermis according to the 2',7'-dichlorodihydrofluorescein diacetate assay. The imiquimod-stimulated psoriasiform animal model indicated a remarkable reduction in erythema, scaling, and overexpressed cytokines upon topical treatment of the nanogels. The transepidermal water loss of the psoriasiform skin was inhibited from 51.7 to 27.0 g/m2/h, suggesting barrier function recovery by the nanocarriers. The nanogels lowered hyperplasia by decreasing the epidermal thickness from 212 to 89 μm. The incorporation of 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS) as a pH-sensitive fluorescence dye in the nanogels could be used to diagnose the severity of the psoriasiform plaque due to the stronger fluorescence of HPTS in skin with lower pH (psoriasiform skin pH = 4.4) than in healthy skin (pH = 4.9). It was possible to deliver the prepared nanogels into the epidermis to restrain hyperplasia without causing cutaneous irritation.

Role of HMGB1 and its associated signaling pathways in human malignancies

The High-Mobility Group Box-1 (HMGB1), a non-histone chromatin-associated protein, plays a crucial role in cancer growth and response to therapy as it retains a pivotal role in promoting both cell death and survival. HMGB1 has been reported to regulate several signaling pathways engaged in inflammation, genome stability, immune function, cell proliferation, cell autophagy, metabolism, and apoptosis. However, the association between HMGB1 and cancer is complex and its mechanism in tumorigenesis needs to be further elucidated. This review aims to understand the role of HMGB1 in human malignancies and discuss the signaling pathways linked to this process to provide a comprehensive understanding on the association of HMGB1 with carcinogenesis. Further, we will review the role of HMGB1 as a target/biomarker for cancer therapy, the therapeutic strategies used to target this protein, and its potential role in preventing or treating cancers. In light of the recent growing evidence linking HMGB1 to cancer progression, we think that it may be suggested as a novel and emergent therapeutic target for cancer therapy. Hence, HMGB1 warrants paramount investigation to comprehensively map its role in tumorigenesis.

The Expression of High Mobility Group Box-1 (HMG1) in the Peripheral Blood and Its Relation with Systemic Vasculitis Patients

Background

We aimed to explore the expression of high mobility group box-1 (HMG1) in the peripheral blood of systemic vasculitis (SV) patients.

Methods

The peripheral blood were collected from 35 healthy controls and 35 SV patients, and the expressions of HMGB1 and pyroptosis-related markers in the samples were detected by ELISA. They were admitted to the Department of Rheumatology and Immunology of the Third Affiliated Hospital of Qiqihar Medical University, China in 2022. The severity of diseases was graded according to the diagnosis and treatment norms of SV. The correlation between HMGB1 expression level and disease-related indicators and grades were explored through Pearson correlation analysis. The specific mechanism of HMGB1 mediating the occurrence and development of diseases through the regulation of endothelial pyroptosis was clarified.

Results

HMGB1 expression significantly increased in the peripheral blood of SV patients compared with healthy controls (P<0.0001). Pearson correlation analysis indicated that HMGB1 expression level in serum gradually increased with the aggravation in SV patients. The expression levels of ASC (P<0.0001), IL-1β (P=0.004) and IL-18 (P<0.0001) in peripheral blood of SV patients were significantly increased, which were significantly positively correlated with HMGB1 in peripheral blood (P<0.0001). Recombinant HMGB1 significantly promoted the expression of ASC, IL-1β and IL-18 in vascular endothelial cells. Recombinant HMGB1 stimulation significantly activated NLRP3 inflammasome, and the additional addition of NLRP3 inhibitor significantly inhibited HMGB1-mediated endothelial pyroptosis.

Conclusion

HMGB1 expression was significantly high in the peripheral blood of SV patients, which was positively correlated with the severity of diseases. HMGB1 could mediate pyroptosis through activating TLR4/NF-κB/NLRP3 signaling pathway.

APOE4-promoted gliosis and degeneration in tauopathy are ameliorated by pharmacological inhibition of HMGB1 release

Apolipoprotein E4 (APOE4) is an important driver of Tau pathology, gliosis, and degeneration in Alzheimer's disease (AD). Still, the mechanisms underlying these APOE4-driven pathological effects remain elusive. Here, we report in a tauopathy mouse model that APOE4 promoted the nucleocytoplasmic translocation and release of high-mobility group box 1 (HMGB1) from hippocampal neurons, which correlated with the severity of hippocampal microgliosis and degeneration. Injection of HMGB1 into the hippocampus of young APOE4-tauopathy mice induced considerable and persistent gliosis. Selective removal of neuronal APOE4 reduced HMGB1 translocation and release. Treatment of APOE4-tauopathy mice with HMGB1 inhibitors effectively blocked the intraneuronal translocation and release of HMGB1 and ameliorated the development of APOE4-driven gliosis, Tau pathology, neurodegeneration, and myelin deficits. Single-nucleus RNA sequencing revealed that treatment with HMGB1 inhibitors diminished disease-associated and enriched disease-protective subpopulations of neurons, microglia, and astrocytes in APOE4-tauopathy mice. Thus, HMGB1 inhibitors represent a promising approach for treating APOE4-related AD.

Discovery and Anti-Inflammatory Activity of a Cyanobacterial Fatty Acid Targeting the Keap1/Nrf2 Pathway

The monounsaturated fatty acid 7(E)-9-keto-hexadec-7-enoic acid (1) and three structurally related analogues with different oxidation states and degrees of unsaturation (2-4) were discovered from a marine benthic cyanobacterial mat collected from Delta Shoal, Florida Keys. Their structures were elucidated using NMR spectroscopy and mass spectrometry. The structure of 1 contained an α,β-unsaturated carbonyl system, a key motif required for the activation of the Keap1/Nrf2-ARE pathway that is involved in the activation of antioxidant and phase II detoxification enzymes. Compounds 1-4 were screened in ARE-luciferase reporter gene assay using stably transfected HEK293 cells, and only 1 significantly induced Nrf2 activity at 32 and 10 µM, whereas 2-4 were inactive. As there is crosstalk between inflammation and oxidative stress, subsequent biological studies were focused on 1 to investigate its anti-inflammatory potential. Compound 1 induced Nqo1, a well-known target gene of Nrf2, and suppressed iNos transcript levels, which translated into reduced levels of nitric oxide in LPS-activated mouse macrophage RAW264.7 cells, a more relevant model for inflammation. RNA sequencing was performed to capture the effects of 1 on a global level and identified additional canonical pathways and upstream regulators involved in inflammation and immune response, particularly those related to multiple sclerosis. A targeted survey of marine cyanobacterial samples from other geographic locations, including Guam, suggested the widespread occurrence of 1. Furthermore, the previous isolation of 1 from marine diatoms and green algae implied a potentially important ecological role across marine algal eukaryotes and prokaryotes. The previous isolation from sea lettuce raises the possibility of dietary intervention to attenuate inflammation and related disease progression.

The activation of SIRT1 ameliorates BPDE-induced inflammatory damage in BEAS-2B cells via HMGB1/TLR4/NF-κB pathway

Benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), the metabolite of environmental pollutant benzo(a)pyrene (B(a)P) could induce pulmonary toxicity and inflammation. SIRT1, an NAD+ -dependent histone deacetylase, is known to regulate inflammation in the occurrence and development of various diseases, but its effects on BPDE-induced acute lung injury are still unknown. The present study aimed to explore the role of SIRT1 in BPDE-induced acute lung injury. Here, human bronchial epithelial (HBE) cells (BEAS-2B) cells were stimulated with BPDE at different concentrations (0.50, 0.75, and 1.00 μmol/L) for 24 h, we found that the levels of cytokines in the supernatant were increased and the expression of SIRT1 in cells was down-regulated, at the same time, BPDE stimulation up-regulated the protein expression of HMGB1, TLR4, and p-NF-κBp65 in BEAS-2B cells. Then the activator and inhibitor of SIRT1 were used before BPDE exposure, it was shown that the activation of SIRT1 significantly attenuated the levels of inflammatory cytokines and HMGB1, and reduced the expression of HMGB1, AC-HMGB1, TLR4, and p-NF-κBp65 protein; while these results were reversed by the inhibition of SIRT1. This study revealed that the SIRT1 activation may protect against BPDE-induced inflammatory damage in BEAS-2B cells by regulating the HMGB1/TLR4/NF-κB pathway.

Revealing the extracellular function of HMGB1 N-terminal region acetylation assisted by a protein semi-synthesis approach

HMGB1 (high-mobility group box 1) is a non-histone chromatin-associated protein that has been widely reported as a representative damage-associated molecular pattern (DAMP) and to play a pivotal role in the proinflammatory process once it is in an extracellular location. Accumulating evidence has shown that HMGB1 undergoes extensive post-translational modifications (PTMs) that actively regulate its conformation, localization, and intermolecular interactions. However, fully characterizing the functional implications of these PTMs has been challenging due to the difficulty in accessing homogeneous HMGB1 with site-specific PTMs of interest. In this study, we developed a streamlined protein semi-synthesis strategy via salicylaldehyde ester-mediated chemical ligations (Ser/Thr ligation and Cys/Pen ligation, STL/CPL). This methodology enabled us to generate a series of N-terminal region acetylated HMGB1 proteins. Further studies revealed that acetylation regulates HMGB1-heparin interaction and modulates HMGB1's stability against thrombin, representing a regulatory switch to control HMGB1's extracellular activity.

HMGB1 released by mesothelial cells drives the development of asbestos-induced mesothelioma

Asbestos is the main cause of malignant mesothelioma. Previous studies have linked asbestos-induced mesothelioma to the release of HMGB1 from the nucleus to the cytoplasm, and from the cytoplasm to the extracellular space. In the cytoplasm, HMGB1 induces autophagy impairing asbestos-induced cell death. Extracellularly, HMGB1 stimulates the secretion of TNFα. Jointly, these two cytokines kick-start a chronic inflammatory process that over time promotes mesothelioma development. Whether the main source of extracellular HMGB1 were the mesothelial cells, the inflammatory cells, or both was unsolved. This information is critical to identify the targets and design preventive/therapeutic strategies to interfere with asbestos-induced mesothelioma. To address this issue, we developed the conditional mesothelial HMGB1-knockout (Hmgb1ΔpMeso) and the conditional myelomonocytic-lineage HMGB1-knockout (Hmgb1ΔMylc) mouse models. We establish here that HMGB1 is mainly produced and released by the mesothelial cells during the early phases of inflammation following asbestos exposure. The release of HMGB1 from mesothelial cells leads to atypical mesothelial hyperplasia, and in some animals, this evolves over the years into mesothelioma. We found that Hmgb1ΔpMeso, whose mesothelial cells cannot produce HMGB1, show a greatly reduced inflammatory response to asbestos, and their mesothelial cells express and secrete significantly reduced levels of TNFα. Moreover, the tissue microenvironment in areas of asbestos deposits displays an increased fraction of M1-polarized macrophages compared to M2 macrophages. Supporting the biological significance of these findings, Hmgb1ΔpMeso mice showed a delayed and reduced incidence of mesothelioma and an increased mesothelioma-specific survival. Altogether, our study provides a biological explanation for HMGB1 as a driver of asbestos-induced mesothelioma.

Ferroptosis-related factors in the substantia nigra are associated with Parkinson's disease

Ferroptosis is an iron-dependent, lipid peroxidation-driven cell death pathway, while Parkinson's disease (PD) patients exhibit iron deposition and lipid peroxidation in the brain. Thus, the features of ferroptosis highly overlap with the pathophysiological features of PD. Despite this superficial connection, the possible role(s) of ferroptosis-related (Fr) proteins in dopaminergic neurons and/or glial cells in the substantia nigra (SN) in PD have not been examined in depth. To explore the correlations between the different SN cell types and ferroptosis at the single-cell level in PD patients, and to explore genes that may affect the sensitivity of dopaminergic neurons to ferroptosis, we performed in silico analysis of a single cell RNA sequence (RNA-seq) set (GSE178265) from the Gene Expression Omnibus (GEO) database. We identified differentially expressed genes (DEGs) in the different cell types in the human SN, and proceeded to perform enrichment analysis, constructing a protein-protein interaction network from the DEGs of dopaminergic neurons with the Metascape database. We examined the intersection of Fr genes present in the FerrDb database with DEGs from the GSE178265 set to identify Fr-DEGs in the different brain cells. Further, we identified Fr-DEGs encoding secreted proteins to implicate cell-cell interactions in the potential stimulation of ferroptosis in PD. The Fr-DEGs we identified were verified using the bulk RNA-seq sets (GSE49036 and GSE20164). The number of dopaminergic neurons decreased in the SN of PD patients. Interestingly, non-dopaminergic neurons possessed the fewest DEGs. Enrichment analysis of dopaminergic neurons' DEGs revealed changes in transmission across chemical synapses and ATP metabolic process in PD. The secreted Fr-DEGs identified were ceruloplasmin (CP), high mobility group box 1 (HMGB1) and transferrin (TF). The bulk RNA-seq set from the GEO database demonstrates that CP expression is increased in the PD brain. In conclusion, our results identify CP as a potential therapeutic target to protect dopaminergic neurons by reducing neurons' sensitivity to ferroptosis.

DNA Polymorphisms and mRNA Levels of Immune Biomarkers as Candidates for Inflammatory Postpartum Disorders Susceptibility in Italian Buffaloes

The immunological genes that may interact with inflammatory postpartum diseases in Italian buffaloes were examined in this study. A total number of 120 female Italian buffaloes (60 normal and 60 with inflammatory reproductive diseases) were employed. Each buffalo's jugular vein was pierced to get five milliliters of blood. To obtain whole blood and extract DNA and RNA, the blood was placed within tubes containing sodium fluoride or EDTA anticoagulants. The immunological (IKBKG, LGALS, IL1B, CCL2, RANTES, MASP2, HMGB1, and S-LZ) genes' nucleotide sequence differences between healthy buffaloes and buffaloes affected by inflammatory reproductive diseases were found by employing PCR-DNA sequencing. According to Fisher's exact test (p ˂ 0.01), there were noticeably different probabilities of all major nucleotide changes spreading among buffalo groups with and without reproductive problems. Buffaloes were significantly more likely to express the examined genes when they had inflammatory reproductive diseases. The outcomes might support the significance of these markers' nucleotide variations and gene expression patterns as indicators of the prevalence of inflammatory reproductive disorders and provide a workable buffalo management policy.

HMGB1 and Toll-like receptors: potential therapeutic targets in autoimmune diseases

HMGB1, a nucleoprotein, is expressed in almost all eukaryotic cells. During cell activation and cell death, HMGB1 can function as an alarm protein (alarmin) or damage-associated molecular pattern (DAMP) and mediate early inflammatory and immune response when it is translocated to the extracellular space. The binding of extracellular HMGB1 to Toll-like receptors (TLRs), such as TLR2 and TLR4 transforms HMGB1 into a pro-inflammatory cytokine, contributing to the occurrence and development of autoimmune diseases. TLRs, which are members of a family of pattern recognition receptors, can bind to endogenous DAMPs and activate the innate immune response. Additionally, TLRs are key signaling molecules mediating the immune response and play a critical role in the host defense against pathogens and the maintenance of immune balance. HMGB1 and TLRs are reported to be upregulated in several autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, type 1 diabetes mellitus, and autoimmune thyroid disease. The expression levels of HMGB1 and some TLRs are upregulated in tissues of patients with autoimmune diseases and animal models of autoimmune diseases. The suppression of HMGB1 and TLRs inhibits the progression of inflammation in animal models. Thus, HMGB1 and TLRs are indispensable biomarkers and important therapeutic targets for autoimmune diseases. This review provides comprehensive strategies for treating or preventing autoimmune diseases discovered in recent years.

Hmgb1 Silencing in the Amygdala Inhibits Pain-Related Behaviors in a Rat Model of Neuropathic Pain

Chronic pain presents a therapeutic challenge due to the highly complex interplay of sensory, emotional-affective and cognitive factors. The mechanisms of the transition from acute to chronic pain are not well understood. We hypothesized that neuroimmune mechanisms in the amygdala, a brain region involved in the emotional-affective component of pain and pain modulation, play an important role through high motility group box 1 (Hmgb1), a pro-inflammatory molecule that has been linked to neuroimmune signaling in spinal nociception. Transcriptomic analysis revealed an upregulation of Hmgb1 mRNA in the right but not left central nucleus of the amygdala (CeA) at the chronic stage of a spinal nerve ligation (SNL) rat model of neuropathic pain. Hmgb1 silencing with a stereotaxic injection of siRNA for Hmgb1 into the right CeA of adult male and female rats 1 week after (post-treatment), but not 2 weeks before (pre-treatment) SNL induction decreased mechanical hypersensitivity and emotional-affective responses, but not anxiety-like behaviors, measured 4 weeks after SNL. Immunohistochemical data suggest that neurons are a major source of Hmgb1 in the CeA. Therefore, Hmgb1 in the amygdala may contribute to the transition from acute to chronic neuropathic pain, and the inhibition of Hmgb1 at a subacute time point can mitigate neuropathic pain.

HMGB1 acts as an agent of host defense at the gut mucosal barrier

Mucosal barriers provide the first line of defense between internal body surfaces and microbial threats from the outside world. ¹ In the colon, the barrier consists of two layers of mucus and a single layer of tightly interconnected epithelial cells supported by connective tissue and immune cells. ² Microbes colonize the loose, outer layer of colonic mucus, but are essentially excluded from the tight, epithelial-associated layer by host defenses. ³ The amount and composition of the mucus is calibrated based on microbial signals and loss of even a single component of this mixture can destabilize microbial biogeography and increase the risk of disease. ^4-7 However, the specific components of mucus, their molecular microbial targets, and how they work to contain the gut microbiota are still largely unknown. Here we show that high mobility group box 1 (HMGB1), the prototypical damage-associated molecular pattern molecule (DAMP), acts as an agent of host mucosal defense in the colon. HMGB1 in colonic mucus targets an evolutionarily conserved amino acid sequence found in bacterial adhesins, including the well-characterized Enterobacteriaceae adhesin FimH. HMGB1 aggregates bacteria and blocks adhesin-carbohydrate interactions, inhibiting invasion through colonic mucus and adhesion to host cells. Exposure to HMGB1 also suppresses bacterial expression of FimH. In ulcerative colitis, HMGB1 mucosal defense is compromised, leading to tissue-adherent bacteria expressing FimH. Our results demonstrate a new, physiologic role for extracellular HMGB1 that refines its functions as a DAMP to include direct, virulence limiting effects on bacteria. The amino acid sequence targeted by HMGB1 appears to be broadly utilized by bacterial adhesins, critical for virulence, and differentially expressed by bacteria in commensal versus pathogenic states. These characteristics suggest that this amino acid sequence is a novel microbial virulence determinant and could be used to develop new approaches to diagnosis and treatment of bacterial disease that precisely identify and target virulent microbes.

Progress in the study of molecular mechanisms of cell pyroptosis in tumor therapy

Pyroptosis, also known as cellular inflammatory necrosis, is a programmed cell death mediated by the Gasdermin family of proteins. The mechanisms by which pyroptosis occurs are divided into the GSDMD-mediated Caspase-1 and Caspase-4/-5/-11-dependent classical inflammatory vesicle pathway and the GSDME-mediated Caspase-3 and granzyme-dependent non-classical inflammatory vesicle pathways, among others. Recent studies have shown that pyroptosis has both inhibitory and promotive effects on tumor development. Pyroptosis induction also plays a dual role in antitumor immunotherapy: on the one hand, it suppresses antitumor immunity by promoting the release of inflammatory factors, and on the other hand, it inhibits tumor cell proliferation by triggering antitumor inflammatory responses. In addition, cell scorching plays an essential role in chemotherapy. It has been found that natural drugs modulating the induction of cell scorch are necessary to treat tumors. Therefore, studying the specific mechanisms of cell pyroptosis in different tumors can provide more ideas for developing oncology drugs. In this paper, we review the molecular mechanisms of pyroptosis and the role of pyroptosis in tumor development and treatment to provide new targets for clinical tumor treatment, prognosis, and antitumor drug development.

Heparin, Low Molecular Weight Heparin, and Non-Anticoagulant Derivatives for the Treatment of Inflammatory Lung Disease

Unfractionated heparin has multiple pharmacological activities beyond anticoagulation. These anti-inflammatory, anti-microbial, and mucoactive activities are shared in part by low molecular weight and non-anticoagulant heparin derivatives. Anti-inflammatory activities include inhibition of chemokine activity and cytokine synthesis, inhibitory effects on the mechanisms of adhesion and diapedesis involved in neutrophil recruitment, inhibition of heparanase activity, inhibition of the proteases of the coagulation and complement cascades, inhibition of neutrophil elastase activity, neutralisation of toxic basic histones, and inhibition of HMGB1 activity. This review considers the potential for heparin and its derivatives to treat inflammatory lung disease, including COVID-19, ALI, ARDS, cystic fibrosis, asthma, and COPD via the inhaled route.

PARP1 Inhibition and Effect on Burn Injury-Induced Inflammatory Response and Cardiac Function

BACKGROUND

Burn injury induces multiple signaling pathways leading to a significant inflammatory storm that adversely affects multiple organs, including the heart. Poly (ADP-ribose) polymerase inhibitor 1 (PARP1) inhibition, with specific agents such as N-(5,6-Dihydro-6-oxo-2-phenanthridinyl)-2-acetamide (PJ34), is effective in reducing oxidative stress and cytokine expression in the heart. We hypothesized that PARP1 inhibition would reduce inflammatory signaling and protect against burn injury-induced cardiac dysfunction.

STUDY DESIGN

Male Sprague-Dawley rats (8 weeks old, 300 to 350 g) were randomly assigned to sham injury (Sham), 60% total body surface area burn (24 hours post burn), or 60% total body surface area burn with intraperitoneal administration of PJ34 (20 mg/kg, 24 hours post burn + PJ34) and sacrificed 24 hours after injury. Cardiac function was determined using Vevo 2100 echocardiography. Genetic expression of 84 specific toll-like receptor-mediated signal transduction and innate immunity genes were examined using microarray to evaluate cardiac tissue. Qiagen GeneGlobe Data Analysis Center was used to analyze expression, and genetic clustering was performed using TreeView V2.0.8 software. Real-time quantitative polymerase chain reaction was used to validate identified differentially expressed genes.

RESULTS

Burn injury significantly altered multiple genes in the toll-like receptor signaling, interleukin-17 signaling, tumor necrosis factor signaling, and nuclear factor-κB signaling pathways and led to significant cardiac dysfunction. PARP1 inhibition with PJ34 normalized these signaling pathways to sham levels as well as improved cardiac function to sham levels.

CONCLUSIONS

PARP1 inhibition normalizes multiple inflammatory pathways that are altered after burn injury and improves cardiac dysfunction. PARP1 pathway inhibition may provide a novel methodology to normalize multiple burn injury-induced inflammatory pathways in the heart.

Etanercept ameliorates psoriasis progression through regulating high mobility group box 1 pathway

BACKGROUND

As a common skin disease, psoriasis is related to inflammation and immune response. Due to the frequent recurrence of psoriasis, the treatment of psoriasis remains a clinical challenge. As an effective tumor necrosis factor-alpha (TNF-α) inhibitor, etanercept has been used for the treatment of psoriasis. However, some patients with psoriasis have no response to etanercept or discontinue treatment. To improve the therapeutic effect of etanercept, searching the potential biomarkers and investigating the related mechanisms of etanercept in the treatment of psoriasis are vital.

MATERIALS AND METHODS

We stimulated HaCaT cells with lipopolysaccharide (LPS) to generate cellular psoriatic changes and established an imiquimod (IMQ)-induced psoriasis-like mouse model, and then used an etanercept to treat cell and mouse model.

RESULTS

Etanercept alleviated IMQ-induced pathological changes and inflammation, and it also decreased the protein expression of high mobility group box 1 (HMGB1), receptor for advanced glycation end-products, and toll-like receptor 4. Moreover, the results of in vitro experiments showed that etanercept inhibited proliferation and inflammation, and promoted cell cycle arrest and apoptosis in LPS-treated HaCaT cells. Knockdown of HMGB1 further enhanced the inhibitory effects of etanercept on LPS-treated HaCaT cell viability and inflammation, while overexpression of HMGB1 notably reversed the inhibitory effects of etanercept on LPS-induced HaCaT cell viability and inflammation.

CONCLUSION

Etanercept inhibited proliferation and inflammation and promoted cell cycle arrest and apoptosis in LPS-induced HaCaT cells, and etanercept ameliorated inflammation in a psoriasis-like mouse model.

PRDX6-mediated pulmonary artery endothelial cell ferroptosis contributes to monocrotaline-induced pulmonary hypertension

BACKGROUND

Pulmonary hypertension (PH) is a life-threatening cardiopulmonary disorder whose underlying pathogenesis is unknown. Our previous study showed that pulmonary endothelial cell (PAEC) ferroptosis is involved in the progression of PH by releasing High-mobility group box 1 (HMGB1) and activating Toll-like receptor 4/NOD-like receptor family pyrin domain containing 3 (TLR4/NLRP3) inflammasome signalling. The precise mechanisms that regulate ferroptosis in PH are unclear. This study aimed to investigate the effect of peroxiredoxin 6 (PRDX6) on PAEC ferroptosis in PH.

METHODS

A rat model of PH was established with monocrotaline (MCT), and the distribution and expression of PRDX6 in the pulmonary artery were examined. Lentiviral vectors carrying PRDX6 (LV-PRDX6) were transfected into PAECs and injected into MCT-induced PH rats. Cell viability, MDA levels, reactive oxygen species (ROS) levels, labile iron pool (LIP) levels and mitochondrial morphology were examined. Ferroptosis-related proteins (NADPH oxidase-4 (NOX4), glutathione peroxidase 4 (GPX4), and ferritin heavy chain 1(FTH1)), TLR4, NLRP3 inflammasome markers, HMGB1 and inflammatory cytokines were examined. Pulmonary vascular remodelling and right ventricular structure and function were measured.

RESULTS

PRDX6 was expressed in PAECs and was significantly decreased in PH. PRDX6 overexpression significantly inhibited ferroptosis in PAECs under PH conditions in vitro and in vivo, as indicated by increased cell viability, decreased MDA, ROS and LIP levels, inhibited mitochondrial damage, upregulated GPX4 and FTH1 expression, and downregulated NOX4 expression. PRDX6 overexpression attenuated pulmonary vascular remodelling and changes in right ventricle structure and function in MCT-induced PH rats. Moreover, PRDX6 overexpression prevented HMGB1 release by PAECs and decreased TLR4 and NLRP3 inflammasome expression and inflammatory cytokine release in macrophages, while RSL3, a specific activator of ferroptosis, reversed these effects.

CONCLUSIONS

Taken together, these findings indicate that PRDX6 regulates PAEC ferroptosis through the release of HMGB1 and activation of the TLR4/NLRP3 inflammasome signalling pathway, providing novel therapeutic targets for the treatment of PH.

Nuclear Fructose-1,6-Bisphosphate Inhibits Tumor Growth and Sensitizes Chemotherapy by Targeting HMGB1

Metabolites are important for cell fate determination. Fructose-1,6-bisphosphate (F1,6P) is the rate-limiting product in glycolysis and the rate-limiting substrate in gluconeogenesis. Here, it is discovered that the nuclear-accumulated F1,6P impairs cancer cell viability by directly binding to high mobility group box 1 (HMGB1), the most abundant non-histone chromosome structural protein with paradoxical roles in tumor development. F1,6P disrupts the association between the HMGB1 A-box and C-tail by targeting K43/K44 residues, inhibits HMGB1 oligomerization, and stabilizes P53 protein by increasing P53-HMGB1 interaction. Moreover, F1,6P lowers the affinity of HMGB1 for DNA and DNA adducts, which sensitizes cancer cells to chemotherapeutic drug(s)-induced DNA replication stress and DNA damage. Concordantly, F1,6P resensitizes cancer cells with chemotherapy resistance, impairs tumor growth and enhances chemosensitivity in mice, and impedes the growth of human tumor organoids. These findings reveal a novel role for nuclear-accumulated F1,6P and underscore the potential utility of F1,6P as a drug for cancer therapy.

A Pharmacological Review of Tanshinones, Naturally Occurring Monomers from Salvia miltiorrhiza for the Treatment of Cardiovascular Diseases

Cardiovascular diseases (CVDs) are a set of heart and blood vessel disorders that include coronary heart disease (CHD), rheumatic heart disease, and other conditions. Traditional Chinese Medicine (TCM) has definite effects on CVDs due to its multitarget and multicomponent properties, which are gradually gaining national attention. Tanshinones, the major active chemical compounds extracted from Salvia miltiorrhiza, exhibit beneficial improvement on multiple diseases, especially CVDs. At the level of biological activities, they play significant roles, including anti-inflammation, anti-oxidation, anti-apoptosis and anti-necroptosis, anti-hypertrophy, vasodilation, angiogenesis, combat against proliferation and migration of smooth muscle cells (SMCs), as well as anti-myocardial fibrosis and ventricular remodeling, which are all effective strategies in preventing and treating CVDs. Additionally, at the cellular level, Tanshinones produce marked effects on cardiomyocytes, macrophages, endothelia, SMCs, and fibroblasts in myocardia. In this review, we have summarized a brief overview of the chemical structures and pharmacological effects of Tanshinones as a CVD treatment to expound on different pharmacological properties in various cell types in myocardia.

Upregulation of HMGB1 promotes vascular dysfunction in the soft palate of patients with obstructive sleep apnea via the TLR4/NF-κB/VEGF pathway

Obstructive sleep apnea (OSA) is characterized by the collapse of the soft palate in the upper airway, resulting in chronic intermittent hypoxia during sleep. Therefore, an understanding of the molecular mechanisms underlying pathophysiological dysfunction of the soft palate in OSA is necessary for the development of new therapeutic strategies. In the present study, we observed that high mobility group protein box 1 (HMGB1) was released by a large infiltration of macrophages in the soft palate of OSA patients. The toll-like receptor 4/nuclear factor kappa B pathway was observed to be activated by the release of HMGB1, and this was accompanied by an increased expression of pro-inflammatory factors, including tumor necrosis factor-α and interleukin-6. Importantly, increased expression of toll-like receptor 4 was observed in endothelial cells, contributing to upregulation of the angiogenesis-related factors vascular endothelial-derived growth factor and matrix metalloproteinase 9. Moreover, we confirmed the effect of the HMGB1-mediated toll-like receptor 4/nuclear factor kappa B pathway on cell proliferation and angiogenesis in an in vitro cell model of human umbilical vein endothelial cells. We conclude that HMGB1 may be a potential therapeutic target for preventing angiogenesis and pathology in OSA.

Glycyrrhizin Interacts with TLR4 and TLR9 to Resolve P. aeruginosa Keratitis

This study tests the mechanism(s) of glycyrrhizin (GLY) protection against P. aeruginosa keratitis. Female C57BL/6 (B6), TLR4 knockout (TLR4KO), myeloid specific TLR4KO (mTLR4KO), their wildtype (WT) littermates, and TLR9 knockout (TLR9KO) mice were infected with P. aeruginosa KEI 1025 and treated with GLY or PBS onto the cornea after infection. Clinical scores, photography with a slit lamp, RT-PCR and ELISA were used. GLY effects on macrophages (Mϕ) and polymorphonuclear neutrophils (PMN) isolated from WT and mTLR4KO and challenged with KEI 1025 were also tested. Comparing B6 and TLR4KO, GLY treatment reduced clinical scores and improved disease outcome after infection and decreased mRNA expression levels in cornea for TLR4, HMGB1, and RAGE in B6 mice. TLR9 mRNA expression was significantly reduced by GLY in both mouse strains after infection. GLY also significantly reduced HMGB1 (B6 only) and TLR9 protein (both B6 and TLR4KO). In TLR9KO mice, GLY did not significantly reduce clinical scores and only slightly improved disease outcome after infection. In these mice, GLY significantly reduced TLR4, but not HMGB1 or RAGE mRNA expression levels after infection. In contrast, in the mTLR4KO and their WT littermates, GLY significantly reduced corneal disease, TLR4, TLR9, HMGB1, and RAGE corneal mRNA expression after infection. GLY also significantly reduced TLR9 and HMGB1 corneal protein levels in both WT and mTLR4KO mice. In vitro, GLY significantly lowered mRNA expression levels for TLR9 in both Mϕ and PMN isolated from mTLR4KO or WT mice after incubation with KEI 1025. In conclusion, we provide evidence to show that GLY mediates its effects by blocking TLR4 and TLR9 signaling pathways and both are required to protect against disease.

Involvement of high-mobility group box-1 and Dermoscopy in diagnosis of psoriasis severity

BACKGROUND/OBJECTIVES

The diagnosis of psoriasis is usually established on clinical grounds but there is lacking of such diagnostic tools to stratify its severity. Psoriasis is a chronic inflammatory disease of skin, nails, and joints. Dermoscopy represent a novel diagnostic tool to diagnose and assess psoriasis severity. The main purpose of this study is to assess the value of dermoscopy associated with serum level of high-mobility group box-1 level (HMGB-1) in the diagnosis and stratification of psoriasis severity.

METHODS

This study included 60 Egyptians subdivided into two equal groups, psoriatic patients, and controls. All patients were subjected first to dermoscopic examination, and then we evaluated the serum levels of HMGB-1 among all studied groups.

RESULTS

The level of HMGB-1 increased in psoriatic patients than controls. There was significant difference between patients and controls in the serum levels of HMGB -1. There were also a positive significant correlation between HMGB-1 and different stages of disease severity. There were also significant correlations between HMGB-1 and specific dermoscopic findings like vascular pattern and vascular number, erythema grades as well as types of scales (Fine, coarse) and (Fine, thick).

CONCLUSIONS

Dermoscopy and HMGB-1 can be considered as a combined novel diagnostic tool for psoriasis severity.

The protective role of glucocerebrosidase/ceramide in rheumatoid arthritis

OBJECTIVE

To clarify the role of glucocerebrosidase (GBA) and Ceramide (Cer) in rheumatoid arthritis (RA).

METHODS

GBA-expressing lentivirus were constructed and injected into collagen-induced arthritis (CIA) mice, and compared with CIA mice injected with empty vector. The severity of arthritis and inflammatory mediators were evaluated. Fibroblast-like synoviocytes (FLS) from RA patients were transfected with GBA-expressing lentivirus, or pretreated with C6-Cer. The migration and invasion of FLS, the production of inflammatory cytokines, and the relevant signaling pathways were assessed.

RESULTS

In CIA mice, GBA markedly improved arthritis compared to that in the CIA mice, with increased content of proteoglycan and integral cartilage surfaces and tidemarks. The circulating inflammatory mediators, including interleukin (IL)-1β, IL-6, IL-18, and matrix metalloproteinase (MMP)-1, were significantly reduced in CIA mice with GBA overexpression compared to those in CIA mice. GBA and C6-Cer treatment inhibited migration and invasion of FLS, and suppressed production of inflammatory cytokines and activation of the MAPK pathways.

CONCLUSION

GBA/Cer exhibited a protective role in CIA mice and RA FLS. These results highlight the potential of targeting GBA/Cer as a therapeutic strategy in RA and warrant further investigation.

Biomarkers in Systemic Juvenile Idiopathic Arthritis, Macrophage Activation Syndrome and Their Importance in COVID Era

Systemic juvenile idiopathic arthritis (sJIA) and its complication, macrophage activation syndrome (sJIA-MAS), are rare but sometimes very serious or even critical diseases of childhood that can occasionally be characterized by nonspecific clinical signs and symptoms at onset-such as non-remitting high fever, headache, rash, or arthralgia-and are biologically accompanied by an increase in acute-phase reactants. For a correct positive diagnosis, it is necessary to rule out bacterial or viral infections, neoplasia, and other immune-mediated inflammatory diseases. Delays in diagnosis will result in late initiation of targeted therapy. A set of biomarkers is useful to distinguish sJIA or sJIA-MAS from similar clinical entities, especially when arthritis is absent. Biomarkers should be accessible to many patients, with convenient production and acquisition prices for pediatric medical laboratories, as well as being easy to determine, having high sensitivity and specificity, and correlating with pathophysiological disease pathways. The aim of this review was to identify the newest and most powerful biomarkers and their synergistic interaction for easy and accurate recognition of sJIA and sJIA-MAS, so as to immediately guide clinicians in correct diagnosis and in predicting disease outcomes, the response to treatment, and the risk of relapses. Biomarkers constitute an exciting field of research, especially due to the heterogeneous nature of cytokine storm syndromes (CSSs) in the COVID era. They must be selected with utmost care-a fact supported by the increasingly improved genetic and pathophysiological comprehension of sJIA, but also of CSS-so that new classification systems may soon be developed to define homogeneous groups of patients, although each with a distinct disease.

Role of High Mobility Group Box 1 in Cardiovascular Diseases

High Mobility Group Box 1 (HMGB1) is a ubiquitous, highly conserved nuclear and cytosolic protein that has diverse biological roles depending on its cellular location and posttranslational modifications. The HMGB1 is localized in the nucleus but can be translocated to the cytoplasm to modulate the intracellular signaling and eventually secreted outside the cells. It is widely established that HMGB1 plays a key role in inflammation; however, the role of HMGB1 in the cardiovascular diseases is not well understood. In this review, we will discuss the latest reports on the pathophysiological link between HMGB1 and cardiovascular complications, with special emphasis on the inflammation. Thus, the understanding of the role of HMGB1 may provide new insights into developing new HMGB1-based therapies.