High Mobility Group Box-1 Protein Research Articles

Serum High Mobility Group Box1 Protein and Toll-like Receptor 4 Correlation with Lipid Profile in Patients with Non-alcoholic Fatty Liver Disease

Serum High Mobility Group Box1 Protein and Toll-like Receptor 4 Correlation with Lipid Profile in Patients with Non-alcoholic Fatty Liver Disease

Inhibition of TOX exerts anti-tumor effects in acute myeloid leukemia by upregulating IRF7 expression

Thymocyte selection-associated high mobility group box protein (TOX) is regarded as a crucial transcription factor involved in T cell exhaustion in acute myeloid leukemia (AML). Previous studies have identified aberrant TOX expression as a major oncogenic driver in hematologic malignancies, indicating that TOX may potentially be both an immune biomarker and an immunotherapy target. However, due to heterogeneity in the distribution patterns of TOX and its correlation with clinical prognosis, the mechanism underlying TOX-mediated tumor immune responses remains unclear. In this study, we demonstrate that high TOX expression in AML patients is associated with poor prognosis, and TOX overexpression promotes AML cell proliferation and restricts apoptosis. In vitro TOX inhibition promoted the apoptosis of AML cells, suppressed cell viability, and induced cell cycle arrest in the G0/G1 phase. Moreover, TOX knockdown could reduce tumor burden in vivo in immunodeficient mice and prolong their survival. Furthermore, the anti-AML effects of inhibiting TOX may act through activation of the IFN-α signal pathway and upregulating IRF7 expression. In summary, we report for the first time that TOX knockdown exerts powerful anti-tumor effects in AML. These findings will provide a theoretical basis for targeted therapy in AML patients.

Effects of electroacupuncture on expression of miR-218 and HMGB1/TLR4 signaling pathway in rats with focal cerebral ischemia

To observe the effect of electroacupuncture (EA) on high mobility group box 1 (HMGB1) / toll-like receptor 4 (TLR4) signaling pathway and inflammatory injury in rats with focal cerebral ischemia (FCI), so as to explore its mechanisms underlying amelioration of ischemic stroke. Male SD rats were randomly divided into sham operation (n=18), model (n=18) and EA (n=18) groups. The FCI model was established according to Longa's method. In the EA group, 24 h after modeling, EA stimulation was applied to "Baihui"(GV20), "Fengfu"(GV16), and "Neiguan" (PC6) and "Xinshu" (BL15) on the left side for 20 min, once a day for 1 week. The neurological deficit severity was evaluated by the modified neurological severity score (mNSS), and the morphological changes of neurons were observed after H.E. staining. The expression of HMGB1 and TLR4 proteins were detected by immunofluorescence staining. The contents of tumor necrosis factor(TNF)-α and interleukin(IL)-6 in the ischemic area tissue of the brain were detected using ELISA. The mRNA expressions of HMGB1 and TLR4 as well as the expression of miR-218 in the ischemic cortex were detected by PCR. Compared with the sham operation group, the mNSS at 2 h, 48 h and 7 day (d), IL-6 and TNF-α contents, HMGB1 and TLR4 immunoactivity and mRNA expression at 48 h and 7 d were significantly increased (P<0.01), while miR-218 expression at 48 h and 7 d was obviously down-regulated (P<0.01) in the model group. In comparison with the model group, the mNSS at 7 d, IL-6 and TNF-α contents, HMGB1 and TLR4 immunoactivity and mRNA expression at 7 d not at 48 h were significantly decreased (P<0.01, P<0.05), while the expression of miR-218 at 7 d was apparently up-regulated (P<0.05) in the EA group. H.E. staining showed that there were signs of neuronal necrosis including blurred outline of the cells, disordered internal structure, dense cytoplasm, shrunk nuclei, etc. in the ischemic area of the brain at 48 h and 7 d in the model group, which was evidently milder on day 7 in the EA group. EA can reduce the inflammatory injury of brain tissue and improve the neurological impairment in rats with FCI, which may be associated with its effects in inhibiting HMGB1/TLR4 signaling and down-regulating the level of pro-inflammatory cytokines.

HMGB1 Modulates Macrophage Metabolism and Polarization in Ulcerative Colitis by Inhibiting Cpt1a Expression.

Macrophage polarization is involved in the development of ulcerative colitis (UC). This study investigated the mechanism by which high mobility group box-1 protein (HMGB1) regulates macrophage polarization through metabolic reprogramming, thereby contributing to the pathogenesis of UC. Dextran sulfate sodium (DSS) was used to induce colitis in mice. RAW264.7 cells were polarized to M1 or M2 macrophages in vitro by stimulating with lipopolysaccharide (LPS)/interferon-γ (IFN-γ) or Interleukin-4 (IL-4), respectively. Macrophage infiltration and distribution within colon tissue were assessed by immunohistochemistry and flow cytometry. Glycolysis, fatty acid oxidation (FAO), and inflammatory factors were evaluated using relevant reagent kits. Chromatin Immunoprecipitation (ChIP) and luciferase reporter experiments were performed to study the regulation of Carnitine palmitoyltransferase 1A (Cpt1a) promoter transcriptional activity by HMGB1. The mouse UC model showed upregulated HMGB1 and increased macrophage infiltration. Overexpression of HMGB1 promoted M1 macrophage polarization, increased glycolysis, and reduced FAO, whereas knockdown of HMGB1 promoted M2 macrophage polarization, reduced glycolysis, and increased FAO. HMGB1 negatively regulated Cpt1a expression by inhibiting transcription of the Cpt1a promoter. Knockdown of Cpt1a reversed the effects of small interfering RNA targeting HMGB1 (si-HMGB1) on macrophage metabolism and polarization. Administration of adeno-associated virus (AAV)-shHMGB1 in vivo caused a reduction in UC symptoms and inflammation. HMGB1 modulates macrophage metabolism in UC by inhibiting Cpt1a expression, leading to increased M1 polarization. This provides a theoretical basis for the clinical application of HMGB1 inhibitors in the treatment of UC.

Effects of pericapsular nerve group block on early postoperative cognitive function in older people undergoing hip arthroplasty: a randomized controlled clinical trial

BackgroundPericapsular nerve group (PENG) block has emerged as a reliable analgesia technique for hip arthroplasty (HA). However, the effects of PENG block on perioperative neurocognitive disorder (PND) after HA has not yet been assessed. The present study aimed to investigate the effects of PENG block on early postoperative cognitive function in older people undergoing hip arthroplasty.MethodsSixty older patients undergoing HA under spinal anesthesia were randomly assigned to group P (n = 30) receiving PENG block with ropivacaine and patient-controlled intravenous analgesia (PCIA) pump with sufentanil after surgery or group C (n = 30) only receiving PCIA pump with sufentanil after surgery. The primary outcome was the Mini-Mental State Examination (MMSE) score at 7 days postoperatively. Secondary outcomes consisted of the incidence of PND 7 days postoperatively, the static VAS pain scores at 6, 12, 24, and 48 h postoperatively; cumulative sufentanil consumption and the requirement of rescue analgesia during the 0–24 h period after surgery; quality of recovery-15 (QoR-15) scale scores at 24 h postoperatively; and the plasma levels of high mobility group box protein 1 (HMGB1) preoperatively and 1 day after surgery, and adverse events.ResultsAfter surgery, the PENG block group had higher MMSE score than the control group at 7 days postoperatively (27.0 ± 1.8 vs. 26.1 ± 1.7, P = 0.048), with a mean difference of 0.9 (95%CI, 0.1–0.9). The incidence of PND at 7 days postoperatively was 6.7% in group P, lower than that of 30% in group C (P = 0.044). In group P, the static VAS scores at 6, 12, and 24 h postoperatively were significantly lower than those in group C (all P < 0.05). Compared with group C, the cumulative sufentanil consumption and the number of patients required rescue analgesia during the 0–24 h period after surgery were significantly lower in group P (all P < 0.05). The scores of QoR-15 scale were higher in group P at 24 h postoperatively than those in group C (P < 0.05). Patients in group P showed lower plasma levels of HMGB1 than group C at 1 day after surgery (P < 0.05), and the rate of complications didn’t differ between both groups.ConclusionsOlder people undergoing HA receiving a PENG block for perioperative analgesia experience improved early postoperative cognitive function, reduced postoperative pain, higher quality of recovery, and less postoperative inflammatory response.Trial registrationChictr.org.cn identifier ChiCTR2200061055 (Date of registry: 15/06/2022, prospectively registered).

Serum High Mobility Group Box 1 (HMGB1) Protein Levels and Cognitive Function in Epilepsy Patients: A Cross-Sectional Study

Background: Epilepsy is a neurological disease with a high incidence rate. Cognitive decline is one of the consequences of recurrent seizures. Neuroinflammation is closely related to the development of epilepsy and cognitive impairment. An increase in the expression and translocation of High Mobility Group Box 1 (HMGB1) from the nucleus to the extracellular space has been observed in epilepsy patients and experimental animal models. This study aimed to investigate the relationship between serum HMGB1 levels and cognitive function in epilepsy patients. Methods: This cross-sectional observational study involved 45 epilepsy patients. Cognitive function was assessed using the Indonesian version of the Montreal Cognitive Assessment (MoCA-Ina), and serum HMGB1 levels were measured using the ELISA technique. The relationship between cognitive function and HMGB1 levels was analyzed using the Kruskal-Wallis test, with a significance level set at p &lt; 0.05. Results: The mean age of the participants was 28.5 years, with a higher proportion of females. The mean serum HMGB1 level was 22.6 ng/ml. No significant relationship was found between serum HMGB1 levels and cognitive function in epilepsy patients (p = 0.188). Conclusion: Serum HMGB1 protein levels were not associated with cognitive function in this sample of epilepsy patients.

Clinical and biochemical assessments of circulating High Mobility Group Box Protein1 in children with epilepsy: relation to cognitive function and drug responsiveness.

Childhood epilepsy is a major health concern posing a significant burden and having disastrous consequences for cognitive function. High Mobility Group Box1 (HMGB1) is an activator of neuroinflammation, and it is possibly involved in the initiation and progression of epilepsy. We aimed to investigate circulating HMGB1 in children with epilepsy and its connection to cognitive function and drug responsiveness. Case-control research included 100 epileptic youngsters and 100 healthy matched controls. Serum HMGB1 was measured using a commercially available ELISA assay. Cognitive functions were evaluated by the Stanford-Binet test 5th edition. Drug-resistant epilepsy (DRE) was found in 37% of the investigated patients. Epileptic children have lower cognitive function parameter levels versus the control group and lower cognitive function in the DRE group compared to the drug-responsive group (P-value < 0.0001). HMGB1 levels were significantly higher in the patients' group (6.279µg/L) compared to the control group (2.093µg/L) and in the drug-resistant group (14.26µg/L) versus the drug-responsive group (4.88µg/L). A significant negative correlation was detected between HMGB1 with Full-scale IQ (r = - 0.547, P = 0.000), Visual-spatial reasoning (r = - 0.501, P = 0.000), fluid reasoning (r = - 0.510, P = 0.000), and working memory (r = - 0.555, P = 0.000). Serum HMGB1 cut-off levels > 6.85µg/L differentiate drug-responsive from resistant patients. Elevated HMGB1 levels, especially in patients with drug-resistant epilepsy, correlate negatively with cognitive performance, emphasizing its importance as a potential marker for early prediction of drug resistance and impairment of cognitive function.

May high mobility group box protein-1 be a biomarker for major depressive disorder?

High Mobility Group Box Protein-1 (HMGB1), which has proinflammatory properties, is known to be involved in psychiatric disorders as far as we know, there are only one clinical studies investigating the role of HMGB1 in major depressive disorder (MDD). In this study, we aimed to investigate the role of HMGB1 in the etiopathogenesis of MDD and whether HMGB1 can be used as a biomarker in MDD by measuring the serum HMGB1 levels of depressed patients in the episode and remission periods. This study included 30 patients diagnosed with MDD in episode, 30 patients in remission and 30 healthy controls. Each group comprised 20 female and 10 male participants. In this study, serum HMGB1 levels were found to be lower in the patient group in the episode compared to the patient group in the remission period and the healthy control group. There was no significant difference between the patient group in remission and the healthy control group in terms of serum HMGB1 levels. The fact that serum HMGB1 levels were lower in the patient group in the episode compared to the patient group in the remission period and the control group may be related to the neuroprotective effects of HMGB1. HMGB1 may be used as a biomarker for MDD.

Impact of immunosuppressive drugs on efficacy of mesenchymal stem cell therapy for suppressing renal fibrosis.

Preemptive regenerative medicine using mesenchymal stem cells (MSCs) may provide a novel therapeutic approach to prevent the progression from organ damage to organ failure. Although immunosuppressive drugs are often used in patients with organ disorder, their impact on MSC therapy remains unclear. We investigated the effects of immunosuppressive drugs on the therapeutic efficacy of MSCs. We created unilateral ureteral obstruction models, as a well-established model of renal fibrosis, a preliminary stage of organ failure. Three immunosuppressive drugs (methylprednisolone, cyclosporine, and cyclophosphamide) were intraperitoneally administered 3 days after surgery, and MSCs were injected via tail vein the following day. Preadministration of methylprednisolone or cyclophosphamide interfered with MSC activation by reducing expression of interferon-gamma (IFN-γ) and high-mobility group box-1 protein, thus significantly attenuating the therapeutic efficacy of MSCs. Preadministration of cyclophosphamide downregulated the expression of stromal cell-derived factor-1/C-X-C motif ligand 12, which is a potent migration factor for MSCs, resulting in reduced MSC engraftment in the renal cortex. IFN-γ-preconditioned activated MSCs were unaffected by these drugs and maintained their beneficial therapeutic effects. Cyclosporine preadministration had no effect on the therapeutic efficacy of MSCs. Our study demonstrated that the administration of certain immunosuppressive drugs interfered with MSC activation and engraftment at the site of injury, resulting in a significant attenuation of their therapeutic efficacy. These findings provide crucial information for selecting patients suitable for MSC therapy. Use of MSCs preactivated with IFN-γ or other means is preferred for patients on methylprednisolone or cyclophosphamide.

High mobility group box-1 protein promotes astrocytic CCL5 production through the MAPK/NF-κB pathway following spinal cord injury

Astrocytes act as immune cells that can produce a series of chemokines to attract large numbers of leucocytes to the lesion site, where they contribute to excessive inflammation following spinal cord injury (SCI). However, the relevant regulatory mechanism involved in chemokine production by astrocytes has not been fully elucidated. In the present study, we examined the correlation between C-C motif chemokine ligand 5 (CCL5) and high mobility group box-1 protein (HMGB1) in a T8–T10 spinal cord contusion model. Our results revealed that SCI-induced CCL5 protein levels increased synchronously with the increase in HMGB1. Administration of an HMGB1-neutralizing antibody significantly reduced the protein expression of CCL5 in the context of SCI. An in vitro study revealed that HMGB1 binding with TLR2/4 receptors potently facilitates the production of CCL5 by astrocytes by activating the intracellular ERK/JNK-mediated NF-κB pathway. Furthermore, the HMGB1-induced release of CCL5 from astrocytes is involved in promoting microglia/macrophage accumulation and M1 polarization. The inhibition of HMGB1 activity reduces microglia/macrophage infiltration by decreasing the expression of CCL5 and improves motor functional recovery following SCI. Our results provide insights into the new functions of HMGB1-mediated astrocytic CCL5 production, which elicits inflammatory cell recruitment to the site of injury; this recruitment is associated with excessive inflammation activation. These data may provide a new therapeutic strategy for central nervous system (CNS) inflammation.

Plasmodium berghei HMGB1 controls the host immune responses and splenic clearance by regulating the expression of pir genes

High mobility group box (HMGB) proteins belong to the high mobility group (HMG) superfamily of non-histone nuclear proteins that are involved in chromatin remodeling, regulation of gene expression, and DNA repair. When extracellular, HMGBs serve as alarmins inducing inflammation, and this is attributed to the proinflammatory activity of box B. Here, we show that Plasmodium HMGB1 has key amino acid changes in box B resulting in the loss of TNF-α stimulatory activity. Site-directed mutagenesis of the critical amino acids in box B with respect to mouse HMGB1 renders recombinant Plasmodium berghei (Pb) HMGB1 capable of inducing TNF-α release. Targeted deletion of PbHMGB1 and a detailed invivo phenotyping show that PbHMGB1 knockout (KO) parasites can undergo asexual stage development. Interestingly, Balb/c mice-infected with PbHMGB1KO parasites display a protective phenotype with subsequent clearance of blood parasitemia and develop long-lasting protective immunity against the challenges performed with Pb wildtype parasites. The characterization of splenic responses shows prominent germinal centers leading to effective humoral responses and enhanced T follicular helper cells. There is also complete protection from experimental cerebral malaria in CBA/CaJ mice susceptible to cerebral pathogenesis with subsequent parasite clearance. Transcriptomic studies suggest the involvement of PbHMGB1 in pir expression. Our findings highlight the gene regulatory function of parasite HMGB1 and its invivo significance in modulating the host immune responses. Further, clearance of asexual stages in PbHMGB1KO-infected mice underscores the important role of parasite HMGB1 in host immune evasion. These findings have implications in developing attenuated blood-stage vaccines for malaria.

Target Gene-Based Association Study of High Mobility Group Box Protein 1 in Intracranial Aneurysms in Koreans.

Objective: We investigated the effect of high mobility group box 1 (HMGB1) on intracranial aneurysms (IAs) by analyzing single-nucleotide polymorphisms (SNPs) based on genome-wide association study (GWAS) data. HMGB1 mRNA and protein expression levels in plasma were also analyzed. Methods: This study was a comprehensive analysis of a GWAS dataset, including 250 patients with IAs and 294 controls. The HMGB1 gene region was targeted within SNP rs3742305 ± 10 kbp. Multivariate logistic regression analysis determined its association with IAs after adjusting for relevant clinical factors. HMGB1 mRNA expression was analyzed in the plasma of 24 patients selected from the GWAS dataset. The HMGB1 protein was analyzed by Western blotting. Results: A total of seven polymorphisms, including rs1360485, rs185382445, rs2039338, rs1045411, rs3742305, rs2249825, and rs189034241, were observed. Two SNPs, including rs1045411 (UTR-3) and rs3742305 (intron), showed strong linkage disequilibrium (r2 = 0.99). However, none of the seven SNPs associated with IAs had an adjusted p-value of < 0.0016 on multiple comparison analysis. HMGB1 mRNA levels (2-ΔCt) did not differ significantly between patients with IAs and the control subjects [1.07 (1.00-1.15) in patients with IAs vs. 1.05 (0.94-1.12) in controls; p = 0.67)]. Also, no significant difference in the degree of plasma HMGB1 protein expression was seen between the two groups (p = 0.82). Conclusions: The number of SNPs associated with HMGB1 and the degree of HMGB1 mRNA and protein expression were not significantly different between patients diagnosed with IAs and the controls.

High Mobility Group Box-1 (HMGB1), a Key Mediator of Cognitive Decline in Neurotrauma with a Potential for Targeted Therapy: A Comprehensive Review.

Neurotrauma plays a significant role in secondary injuries by intensifying the neuroinflammatory response in the brain. High Mobility Group Box-1 (HMGB1) protein is a crucial neuroinflammatory mediator involved in this process. Numerous studies have hypothesized about the underlying pathophysiology of HMGB1 and its role in cognition, but a definitive link has yet to be established. Elevated levels of HMGB1 in the hippocampus and serum have been associated with declines in cognitive performance, particularly in spatial memory and learning. This review also found that inhibiting HMGB1 can improve cognitive deficits following neurotrauma. Interestingly, HMGB1 levels are linked to the modulation of neuroplasticity and may offer neuroprotective effects in the later stages of neurotraumatic events. Consequently, administering HMGB1 during the acute phase may help reduce neuroinflammatory effects that lead to cognitive deficits in the later stages of neurotrauma. However, further research is needed to understand the time-dependent regulation of HMGB1 and the clinical implications of treatments targeting HMGB1 after neurotrauma.

Macrophages-derived high-mobility group box-1 protein induces endothelial progenitor cells pyroptosis

Endothelial dysfunction is an important factor in the progress of sepsis. Endothelial progenitor cells (EPCs) are the precursor cells of endothelial cells and play a crucial role in the prognosis and treatment of sepsis. EPCs in the peripheral blood of patients with sepsis undergo pyroptosis, but the mechanism remains much of unknown. Serum high-mobility group box-1 (HMGB1) is significantly elevated in patients with sepsis, but whether it is related to EPCs pyroptosis is unknown. We used a cell model of sepsis invitro to isolate EPCs for better observation. By detecting the pyroptosis-related indicators of EPCs and the level of release and acetylation of HMGB1 in inflammatory macrophages, it was found that HMGB1 released by inflammatory macrophages combined with receptor for advanced glycation end products (RAGE) is a key pathway to induce pyroptosis of EPCs.

Glucocorticoids induce HMGB1 release in primary cultured rat cortical microglia

Stress, a risk factor for major depressive disorder and Alzheimer disease, leads to the release of high-mobility group box-1 (HMGB1) protein, which in turn causes neuroinflammation. The mechanism underlying stress-induced HMGB1 release is unknown, but stress-associated glucocorticoids could be involved. Primary cultured rat cortical microglia and neurons were treated with corticosterone, a stress-associated glucocorticoid, and HMGB1 release was measured by ELISA and western blotting to test this hypothesis. With corticosterone treatment, significant HMGB1 was released in microglia but not in neuronal cell cultures. HMGB1 mRNA expression and HMGB1 protein expression in microglia were not affected by corticosterone treatment. Thus, the source of extracellular HMGB1 released into the medium is likely to be existing nuclear HMGB1 rather than newly synthesized HMGB1. Corticosterone-induced HMGB1 release in microglia culture was significantly attenuated by blocking glucocorticoid receptors but not mineralocorticoid receptors. Dexamethasone, a selective glucocorticoid receptor agonist, and dexamethasone-bovine serum albumin (BSA), a membrane-impermeable glucocorticoid receptor agonist used to confirm the membrane receptor-mediated effects of glucocorticoids, increased the release of HMGB1. Immunocytochemistry showed that HMGB1 translocated from the nucleus to the cytoplasm following dexamethasone or dexamethasone-BSA treatment through glucocorticoid receptors. The present findings suggest that glucocorticoids stimulate microglial membrane glucocorticoid receptors and trigger cytoplasmic translocation and extracellular release of nuclear HMGB1. Thus, under stress conditions, glucocorticoids induce microglial HMGB1 release, leading to a neuroinflammatory state that could mediate neurological disorders.

Brain and Lung Biomarker Responses to Hyperoxic Hypobaric Decompression.

INTRODUCTION: Biomarker responses to intensive decompression indicate systemic proinflammatory responses and possible neurological stress. To further investigate responses, 12 additional brain and lung biomarkers were assayed.METHODS: A total of 15 healthy men (20 to 50 yr) undertook consecutive same-day ascents to 25,000 ft (7620 m), following denitrogenation, breathing 100% oxygen. Venous blood was sampled at baseline (T0), after the second ascent (T8), and next morning (T24). Soluble protein markers of brain and lung insult were analyzed by enzyme-linked immunosorbent assay with plasma microparticles quantified using flow cytometry.RESULTS: Levels of monocyte chemoattractant protein-1 and high mobility group box protein 1 were elevated at T8, by 36% and 16%, respectively, before returning to baseline. Levels of soluble receptor for advanced glycation end products fell by 8%, recovering by T24. Brain-derived neurotrophic factor rose by 80% over baseline at T24. Monocyte microparticle levels rose by factors of 3.7 at T8 and 2.7 at T24 due to early and late responses in different subjects. Other biomarkers were unaffected or not detected consistently.DISCUSSION: The elevated biomarkers at T8 suggest a neuroinflammatory response, with later elevation of brain-derived neurotrophic factor at T24 indicating an ongoing neurotrophic response and incomplete recovery. A substantial increase at T8 in the ratio of high mobility group box protein 1 to soluble receptor for advanced glycation end products suggests this axis may mediate the systemic inflammatory response to decompression. The mechanism of neuroinflammation is unclear but elevation of monocyte microparticles and monocyte chemoattractant protein-1 imply a key role for activated monocytes and/or macrophages.Connolly DM, Madden LA, Edwards VC, Lee VM. Brain and lung biomarker responses to hyperoxic hypobaric decompression. Aerosp Med Hum Perform. 2024; 95(9):667-674.

Serum Level of High-mobility Group Box Protein-1 in Children with Sepsis, Severe Sepsis and Septic Shock

Serum Level of High-mobility Group Box Protein-1 in Children with Sepsis, Severe Sepsis and Septic Shock

Mar1, a high mobility group box protein, regulates n-alkane adsorption and cell morphology of the dimorphic yeast Yarrowia lipolytica.

The dimorphic yeast Yarrowia lipolytica possesses an excellent ability to utilize n-alkane as a sole carbon and energy source. Although there are detailed studies on the enzymes that catalyze the reactions in the metabolic processes of n-alkane in Y. lipolytica, the molecular mechanism underlying the incorporation of n-alkane into the cells remains to be elucidated. Because Y. lipolytica adsorbs n-alkane, we postulated that Y. lipolytica incorporates n-alkane through direct interaction with it. We isolated and characterized mutants defective in adsorption to n-hexadecane. One of the mutants harbored a nonsense mutation in MAR1 (Morphology and n-alkane Adsorption Regulator 1) encoding a protein containing a high mobility group box. The deletion mutant of MAR1 exhibited defects in adsorption to n-hexadecane and filamentous growth on solid media, whereas the strain that overexpressed MAR1 exhibited hyperfilamentous growth. Fluorescence microscopic observations suggested that Mar1 localizes in the nucleus. RNA-sequencing analysis revealed the alteration of the transcript levels of several genes, including those encoding transcription factors and cell surface proteins, by the deletion of MAR1. These findings suggest that MAR1 is involved in the transcriptional regulation of the genes required for n-alkane adsorption and cell morphology transition.IMPORTANCEYarrowia lipolytica, a dimorphic yeast capable of assimilating n-alkane as a carbon and energy source, has been extensively studied as a promising host for bioconversion of n-alkane into useful chemicals and bioremediation of soil and water contaminated by petroleum. While the metabolic pathway of n-alkane in this yeast and the enzymes involved in this pathway have been well characterized, the molecular mechanism to incorporate n-alkane into the cells is yet to be fully understood. Due to the ability of Y. lipolytica to adsorb n-alkane, it has been hypothesized that Y. lipolytica incorporates n-alkane through direct interaction with it. In this study, we identified a gene, MAR1, which plays a crucial role in the transcriptional regulation of the genes necessary for the adsorption to n-alkane and the transition of the cell morphology in Y. lipolytica. Our findings provide valuable insights that could lead to advanced applications of Y. lipolytica in n-alkane bioconversion and bioremediation.

High mobility group box1 (HMGB1) is a potential disease biomarker in cell and mouse models of Duchenne muscular dystrophy.

Duchenne muscular dystrophy (DMD) is a progressive muscle wasting disorder affecting 1:3500 male births and is associated with myofiber degeneration, regeneration, and inflammation. Glucocorticoid treatments have been the standard of care due to immunomodulatory/immunosuppressive properties but novel genetic approaches, including exon skipping and gene replacement therapy, are currently being developed. The identification of additional biomarkers to assess DMD-related inflammatory responses and the potential efficacy of these therapeutic approaches are thus of critical importance. The current study uses RNA sequencing of skeletal muscle from two mdx mouse models to identify high mobility group box1 (HMGB1) as a candidate biomarker potentially contributing to DMD-related inflammation. HMGB1 protein content was increased in a human iPSC-derived skeletal myocyte model of DMD and microdystrophin treatment decreased HMGB1 back to control levels. In vivo, HMGB1 protein levels were increased in vehicle treated B10-mdx skeletal muscle compared to B10-WT and significantly decreased in B10-mdx animals treated with adeno-associated virus (AAV)-microdystrophin. However, HMGB1 protein levels were not increased in D2-mdx skeletal muscle compared to D2-WT, demonstrating a strain-specific difference in DMD-related immunopathology.

Effects of artemisinin and cisplatin on the malignant progression of oral leukoplakia. In vitro and in vivo study

ObjectivesChemoprevention can be a treatment for potentially malignant lesions (PMLs). We aimed to evaluate whether artemisinin (ART) and cisplatin (CSP) are associated with apoptosis and immunogenic cell death (ICD) in vitro, using oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC) cell lines, and whether these compounds prevent OL progression in vivo.MethodsNormal keratinocytes (HaCat), Dysplastic oral cells (DOK), and oral squamous cell carcinoma (SCC-180) cell lines were treated with ART, CSP, and ART + CSP to analyze cytotoxicity, genotoxicity, cell migration, and increased expression of proteins related to apoptosis and ICD. Additionally, 41 mice were induced with OL using 4NQO, treated with ART and CSP, and their tongues were histologically analyzed.ResultsIn vitro, CSP and CSP + ART showed dose-dependent cytotoxicity and reduced SCC-180 migration. No treatment was genotoxic, and none induced expression of proteins related to apoptosis and ICD; CSP considerably reduced High-mobility group box-1 (HMGB-1) protein expression in SCC-180. In vivo, there was a delay in OL progression with ART and CSP treatment; however, by the 16th week, only CSP prevented progression to OSCC.ConclusionExpression of proteins related to ICD and apoptosis did not increase with treatments, and CSP was shown to reduce immunogenic pathways in SCC-180, while reducing cell migration. ART did not prevent the malignant progression of OL in vivo; CSP did despite significant adverse effects.