Hmo1 Promotes Efficient Transcription Elongation by RNA Polymerase I in Saccharomyces cerevisiae.

RNA polymerase I (Pol I) is responsible for synthesizing the three largest eukaryotic ribosomal RNAs (rRNAs), which form the backbone of the ribosome. Transcription by Pol I is required for cell growth and, therefore, is subject to complex and intricate regulatory mechanisms. To accomplish this robust regulation, the cell engages a series of trans-acting transcription factors. One such factor, high mobility group protein 1 (Hmo1), has long been established as a trans-acting factor for Pol I in Saccharomyces cerevisiae; however, the mechanism by which Hmo1 promotes rRNA synthesis has not been defined. Here, we investigated the effect of the deletion of HMO1 on transcription elongation by Pol I in vivo. We determined that Hmo1 is an important activator of transcription elongation, and without this protein, Pol I accumulates across rDNA in a sequence-specific manner. Our results demonstrate that Hmo1 promotes efficient transcription elongation by rendering Pol I less sensitive to pausing in the G-rich regions of rDNA.

Hyperoside attenuates carbon tetrachloride-induced hepatic fibrosis via the poly(ADP-ribose)polymerase-1-high mobility group protein 1 pathway.

Oxidative stress and inflammation have been implicated in hepatic fibrosis. Antioxidant and anti-inflammatory activities are among the pharmacological effects of hyperoside. This study aimed to evaluate the impact of hyperoside on hepatic fibrosis and elucidate the underlying processes that perpetuate this relationship. The findings indicated that hyperoside significantly protects mouse livers against damage, inflammation, and fibrosis. Specifically, attenuation of hepatic fibrosis is associated with lower expression of HMGB1 protein and reduced expression of Toll-like receptor 4, PARP-1, and nuclear factor-kB (NF-κB) p65 mRNA and protein. Furthermore, hyperoside inhibited the cytoplasmic translocation of HMGB1 and nuclear localization of NF-κB p65 in the hepatic tissues of mice. The results of this study indicate that hyperoside may impose a blocking or reversing effect on hepatic fibrosis; additionally, the corresponding hyperoside-dependent mechanism may be linked to PARP-1-HMGB1 pathway regulation.

Acteoside ameliorates hepatic ischemia-reperfusion injury via reversing the senescent fate of liver sinusoidal endothelial cells and restoring compromised sinusoidal networks.

Hepatic ischemia-reperfusion injury (HIRI), a common two-phase intersocietal reaction in liver surgery, typically leading to sustained liver dysfunction. During this process, liver sinusoidal endothelial cells (LSECs) are vulnerable to damage and exert senescence-associated secretory phenotype (SASP). However, how these SASP-LSECs secreted damage-associated molecular patterns (DAMPs) to impact the whole HIRI microenvironment and whether it can be reversed by therapeutics remains unknown. Here, we found that either HIRI surgery or hypoxia and reoxygenation (HR) stimulation forced LSECs into SASP and expressed HMGB1-dominated DAMPs, which were dramatically improved by acteoside (ACT). Additionally, hypoxic hepatocytes released excessive HMGB1 to LSECs and synergistically aggravated their SASP state. Mechanistically, HMGB1 bound with TLR3/TLR4 on LSECs, promoted the nuclear translocation of IRF1 and subsequent transcription of cxcl1 and Hmgb1, leading to the chemotaxis of neutrophils and accelerating immune damage in a vicious circle. Notably, ACT or HMGB1 siRNA effectively disrupted HMGB1-TLR3/4 interaction, leading to IRF1 inhibition and repairing LSEC functions, which was largely reversed by HMGB1 stimulation and IRF1-overexpressed liposomes with LSECs-targeted hyaluronic acid-derivative conjugated in mice. Collectively, ACT reversed the senescent fate of LSECs and restored sinusoidal networks by targeting HMGB1-TLR3/4-IRF1 signaling, thus providing protection against HIRI and offering the potential for new therapeutics development.

Receptor for Advanced Glycation End Products (RAGE): A Pivotal Hub in Immune Diseases.

As a critical molecule in the onset and sustainment of inflammatory response, the receptor for advanced glycation end products (RAGE) has a variety of ligands, such as advanced glycation end products (AGEs), S100/calcium granule protein, and high-mobility group protein 1 (HMGB1). Recently, an increasing number studies have shown that RAGE ligand binding can initiate the intracellular signal cascade, affect intracellular signal transduction, stimulate the release of cytokines, and play a vital role in the occurrence and development of immune-related diseases, such as systemic lupus erythematosus, rheumatoid arthritis, and Alzheimer's disease. In addition, other RAGE signaling pathways can play crucial roles in life activities, such as inflammation, apoptosis, autophagy, and endoplasmic reticulum stress. Therefore, the strategy of targeted intervention in the RAGE signaling pathway may have significant therapeutic potential, attracting increasing attention. In this paper, through the systematic induction and analysis of RAGE-related signaling pathways and their regulatory mechanisms in immune-related diseases, we provide theoretical clues for the follow-up targeted intervention of RAGE-mediated diseases.

[Dihydromyricetin improves cardiac insufficiency by inhibiting HMGB1 in diabetic rats].

OBJECTIVE: To investigate the effect of dihydromyricetin (DHM) on cardiac insufficiency in diabetic rats and explore the underlying mechanism. METHOD: Twenty-four male SD rats were randomized equally into normal control group, type 2 diabetes (T2DM) group fed on a high-glucose and high-fat diet for 6 weeks with low-dose streptozotocin (STZ) injection, metformin (MET) group with daily intragastric administration of MET (150 mg/kg) for 8 weeks after T2DM modeling, and dihydromyricetin (DHM) group with daily intragastric administration of DHM (250 mg/kg) for 8 weeks after modeling. The levels of fasting blood glucose, low density lipoprotein (LDL-C), triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL-C) and glycosylated hemoglobin (HbA1c) of the rats were measured, and plasma levels of insulin and high mobility group protein-1 (HMGB1) were detected with ELISA. The cardiac function of the rats was assessed using color echocardiography, ECG was measured using a biological signal acquisition system, and myocardial pathology was observed with HE staining. The protein expressions of HMGB1, nuclear factor-κB (NF-κB) p65 and phospho-NF-κB p65 (p-NF-κB p65) in the myocardial tissue were detected using Western blotting. RESULTS: Compared with the control group, the rats in T2DM group showed significant anomalies in cardiac function after modeling with significantly increased plasma HMGB1 level and expressions of HMGB1, NF-κB p65 and p-NF-κB p65 proteins in the myocardial tissue (P < 0.05 or 0.01). Treatment with DHM significantly improved the indexes of cardiac function of the diabetic rats (P < 0.05 or 0.01), decreased plasma HMGB1 level and down-regulated the protein expressions of HMGB1 and p-NF-κB p65 in the myocardial tissue (P < 0.05 or 0.01). CONCLUSION: DHM treatment can improve cardiac function in diabetic rats possibly by down-regulation of HMGB1 and phospho-NF-κB p65 expressions in the myocardium.

Tanreqing Injection Attenuates Macrophage Activation and the Inflammatory Response via the lncRNA-SNHG1/HMGB1 Axis in Lipopolysaccharide-Induced Acute Lung Injury.

The etiology of acute lung injury (ALI) is not clear, and the treatment of ALI presents a great challenge. This study aimed to investigate the pathogenesis and potential therapeutic targets of ALI and to define the target gene of Tanreqing (TRQ), which is a traditional Chinese medicine formula composed of five medicines, scutellaria baicalensis, bear bile powder, goat horn powder, honeysuckle and forsythia. Macrophage activation plays a critical role in many pathophysiological processes, such as inflammation. Although the regulation of macrophage activation has been extensively investigated, there is little knowledge of the role of long noncoding RNAs (lncRNAs) in this process. In this study, we found that lncRNA-SNHG1 expression is distinctly regulated in differently activated macrophages in that it is upregulated in LPS. LncRNA-SNHG1 knockdown attenuates LPS-induced M1 macrophage activation. The SNHG1 promoter was bound by NF-κB subunit p65, indicative of SNHG1 being a direct transcriptional target of LPS-induced NF-κB activation. SNHG1 acts as a proinflammatory driver that leads to the production of inflammatory cytokines and the activation of macrophages and cytokine storms by physically interacting with high-mobility group box 1 (HMGB1) in ALI. TRQ inhibited NF-κB signaling activation and binding of NF-κB to the SNHG1 promoter. In conclusion, this study defined TRQ target genes, which can be further elucidated as mechanism(s) of TRQ action, and provides insight into the molecular pathogenesis of ALI. The lncRNA-SNHG1/HMGB1 axis is an ideal therapeutic for ALI treatment.

circ­LRP6 contributes to osteosarcoma progression by regulating the miR­141­3p/HDAC4/HMGB1 axis.

Circular RNA­lipoprotein receptor 6 (circ­LRP6) serves a role in promoting the tumorigenesis of retinoblastoma, esophageal squamous cell cancer and oral squamous cell carcinoma; however, whether circ­LRP6 demonstrates the same effect in osteosarcoma (OS) is yet to be fully elucidated. The present study aimed to analyze the expression, role and potential molecular mechanism of circ­LRP6 in OS. The expression levels of circ­LRP6, microRNA (miR)­141­3p, histone deacetylase 4 (HDAC4) and high mobility group protein 1 (HMGB1) were evaluated by reverse transcription-quantitative PCR in OS tissues and cell lines. Cell Counting Kit­8, Transwell and Matrigel assays were conducted to evaluate cell proliferation, migration and invasion, respectively. Western blotting was also performed to determine HDAC4 and HMGB1 protein expression levels. Bioinformatics and dual­luciferase reporter assays were used to predict and analyze the interactions between circ­LRP6 and miR­141­3p, miR­141­3p and HDAC4, as well as between miR­141­3p and HMGB1. Additionally, RNA immunoprecipitation was performed to verify the association between circ­LRP6 and miR­141­3p. The results confirmed that circ­LRP6 was highly expressed in OS tissues and cell lines. In addition, circ­LRP6 negatively regulated the expression of miR­141­3p and, in turn, miR­141­3p negatively regulated HDAC4 and HMGB1 expression. Functional assays revealed that circ­LRP6 knockdown inhibited the proliferation, migration and invasion of OS cells, whereas the inhibition of miR­141­3p or the overexpression of either HDAC4 or HMGB1 partly reversed the inhibitory effect of circ­LRP6 knockdown. In summary, the present study determined that circ­LRP6 knockdown inhibited the proliferation, migration and invasion of OS cells by regulating the miR­141­3p/HDAC4/HMGB1 axis.

Role of HMGB1 in TNF-α Combined with Z-VAD-fmk-Induced L929 Cells Necroptosis.

The present study established a necroptosis model in vitro and investigated the role of HMGB1 in cell necroptosis. A combination of tumor necrosis factor-α and z-VAD-fmk was used to induce necroptosis in L929 cells with necroptosis inhibitor necrostatin-1 applied as an intervention. Flow cytometry and transmission electron microscopy (TEM) were used to measure cell necroptosis. Western blotting assay was applied to detect the expression of receptor-interacting serine/threonine-protein kinase 3 (RIPK3), mixed lineage kinase domain-like pseudokinase (MLKL) and HMGB1. Co-immunoprecipitation (Co-IP) assay was used to confirm the interaction between HMGB1 and RIPK3. Our study demonstrated that HMGB1 migrated from the nucleus to the cytoplasm at the onset of necroptosis and was subsequently released passively to the extracellular matrix. Further experiments determined that the binding of HMGB1 with RIPK3 in the cytoplasm was loose during necroptosis. By contrast, when necroptosis was inhibited, the interaction in the cytoplasm was tight suggesting that this association between HMGB1 and RIPK3 might affect its occurrence. In conclusion, the transfer of HMGB1 from nucleus to cytoplasm, and its interaction with RIPK3 might be potentially involved in necroptosis.

Determination of HMGB1 in hepatitis B virus-related acute-on-chronic liver failure patients with acute kidney injury: Early prediction and prognostic implications.

Background: Acute kidney injury (AKI) is a frequent complication in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) and is associated with high rates of mortality. We aimed to estimate serum high mobility group protein 1 (HMGB1) levels in hepatitis B virus-related acute-on-chronic liver failure patients and analyze their clinical value in the development and outcomes of Acute kidney injury. Methods: A total of 251 consecutive patients with hepatitis B virus-related acute-on-chronic liver failure were enrolled in this retrospective study. Using the International Club of Ascites staging criteria of Acute kidney injury, 153 patients developed Acute kidney injury. The clinical data of patients were collected and serum levels of high mobility group protein 1 were measured by ELISA. All patients were followed up until death or for a minimum of 3 months. Early prediction and prognostic implications of high mobility group protein 1 in Hepatitis B Virus-Related Acute-on-Chronic Liver Failure Patients with Acute Kidney Injury were investigated in different cohorts, including a propensity score-matched ACLF cohort. Results: Among all individuals with hepatitis B virus-related acute-on-chronic liver failure, the incidence of Acute kidney injury was 61.0% (153/251). The patients who developed stage 2/3 Acute kidney injury showed the highest high mobility group protein 1 levels, followed by those who developed stage 1 Acute kidney injury, and those without Acute kidney injury showed the lowest high mobility group protein 1 levels. Moreover, high mobility group protein 1 levels were significantly higher in non-survivors than in survivors among hepatitis B virus-related acute-on-chronic liver failure patients with Acute kidney injury. Furthermore, analysis of the area under the receiver operating characteristic curve (AUROC) indicated that serum high mobility group protein 1 levels (pre-matching: AUC = 0.740; post-matching: AUC = 0.661) may be a potential predictive factor for Acute kidney injury development and that high mobility group protein 1 (AUC = 0.727) might be a reliable biomarker for prognosis in patients with Acute kidney injury. Conclusion: In patients with hepatitis B virus-related acute-on-chronic liver failure, Acute kidney injury is universal. Acute kidney injury and its stages negatively influence the 90-day transplant-free mortality rate. Serum high mobility group protein 1 levels can serve as a positive predictor of Acute kidney injury development, and high mobility group protein 1 might also be a prognostic biomarker for Acute kidney injury among hepatitis B virus-related acute-on-chronic liver failure patients.

Dihydromyricetin improves cardiac insufficiency by inhibiting HMGB1 in diabetic rats / 南方医科大学学报

OBJECTIVE@#To investigate the effect of dihydromyricetin (DHM) on cardiac insufficiency in diabetic rats and explore the underlying mechanism.@*METHOD@#Twenty-four male SD rats were randomized equally into normal control group, type 2 diabetes (T2DM) group fed on a high-glucose and high-fat diet for 6 weeks with low-dose streptozotocin (STZ) injection, metformin (MET) group with daily intragastric administration of MET (150 mg/kg) for 8 weeks after T2DM modeling, and dihydromyricetin (DHM) group with daily intragastric administration of DHM (250 mg/kg) for 8 weeks after modeling. The levels of fasting blood glucose, low density lipoprotein (LDL-C), triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL-C) and glycosylated hemoglobin (HbA1c) of the rats were measured, and plasma levels of insulin and high mobility group protein-1 (HMGB1) were detected with ELISA. The cardiac function of the rats was assessed using color echocardiography, ECG was measured using a biological signal acquisition system, and myocardial pathology was observed with HE staining. The protein expressions of HMGB1, nuclear factor-κB (NF-κB) p65 and phospho-NF-κB p65 (p-NF-κB p65) in the myocardial tissue were detected using Western blotting.@*RESULTS@#Compared with the control group, the rats in T2DM group showed significant anomalies in cardiac function after modeling with significantly increased plasma HMGB1 level and expressions of HMGB1, NF-κB p65 and p-NF-κB p65 proteins in the myocardial tissue (P < 0.05 or 0.01). Treatment with DHM significantly improved the indexes of cardiac function of the diabetic rats (P < 0.05 or 0.01), decreased plasma HMGB1 level and down-regulated the protein expressions of HMGB1 and p-NF-κB p65 in the myocardial tissue (P < 0.05 or 0.01).@*CONCLUSION@#DHM treatment can improve cardiac function in diabetic rats possibly by down-regulation of HMGB1 and phospho-NF-κB p65 expressions in the myocardium.

[Mechanism of high expression of high mobility group protein 1 in a rat model of knee osteoarthritis].

OBJECTIVE: To investigate the molecular mechanism triggering pyroptosis of synovial fibroblast-like synoviocytes(FLSs)and the release of high mobility group protein 1(HMGB1)in a rat model of knee osteoarthritis(KOA). METHODS: Twelve SD rats were randomized equally into blank control group without any treatment and KOA group with anterior cruciate ligament amputation (ACLT) to induce KOA.HE staining and Mankin score were used to evaluate the damage of knee cartilage.Western blotting was used to detect the expression of pyroptosis-related proteins and HMGB1 in the synovial tissue.In the cell experiment, rat FLSs were treated with PBS (control group), LPS+ATP (to induce cell pyroptosis), or LPS+ATP+siRNAs (to inhibit pyroptosis of the FLSs), and the cellular expressions of apoptosis-related proteins and HMGB1 were detected using Western blotting; the level of HMGB1 in the culture supernatant was detected with ELISA. RESULTS: In the rat models of KOA, the expressions of pyroptosis-related proteins and HMGB1 in the synovial tissue and Mankin score were significantly increased as compared with those in the control group(P < 0.05).In cultured rat FLSs, the expressions of apoptosis related proteins and HMGB1 were significantly higher in the pyroptosis group than in the control group and in cells transfected with the siRNAs targeting NLRP1, NLRP3, ASC and caspase-1(P < 0.05).The protein level of HMGB1 in the culture supernatant was significantly higher in pyroptosis group than in the control and siRNA groups (P < 0.05). CONCLUSION: In the pathological process of KOA, NLRPs inflammasome-mediated FLS pyroptosis causes massive release of HMGB1, which is associated with the activation of the downstream molecule caspase-1.

Celastrol exerts a neuroprotective effect by directly binding to HMGB1 protein in cerebral ischemia-reperfusion.

BACKGROUND: Celastrol (cel) was one of the earliest isolated and identified chemical constituents of Tripterygium wilfordii Hook. f. Based on a cel probe (cel-p) that maintained the bioactivity of the parent compound, the targets of cel in cerebral ischemia-reperfusion (I/R) injury were comprehensively analyzed by a quantitative chemical proteomics method. METHODS: We constructed an oxygen-glucose deprivation (OGD) model in primary rat cortical neurons and a middle cerebral artery occlusion (MCAO) model in adult rats to detect the direct binding targets of cel in cerebral I/R. By combining various experimental methods, including tandem mass tag (TMT) labeling, mass spectrometry, and cellular thermal shift assay (CETSA), we revealed the targets to which cel directly bound to exert neuroprotective effects. RESULTS: We found that cel inhibited the proinflammatory activity of high mobility group protein 1 (HMGB1) by directly binding to it and then blocking the binding of HMGB1 to its inflammatory receptors in the microenvironment of ischemia and hypoxia. In addition, cel rescued neurons from OGD injury in vitro and decreased cerebral infarction in vivo by targeting HSP70 and NF-κB p65. CONCLUSION: Cel exhibited neuroprotective and anti-inflammatory effects by targeting HSP70 and NF-κB p65 and directly binding to HMGB1 in cerebral I/R injury.

Nicotinic cholinergic system and COVID-19: In silico evaluation of nicotinic acetylcholine receptor agonists as potential therapeutic interventions.

SARS-CoV-2 infection was announced as a pandemic in March 2020. Since then, several scientists have focused on the low prevalence of smokers among hospitalized COVID-19 patients. These findings led to our hypothesis that the Nicotinic Cholinergic System (NCS) plays a crucial role in the manifestation of COVID-19 and its severe symptoms. Molecular modeling revealed that the SARS-CoV-2 Spike glycoprotein might bind to nicotinic acetylcholine receptors (nAChRs) through a cryptic epitope homologous to snake toxins, substrates well documented and known for their affinity to the nAChRs. This binding model could provide logical explanations for the acute inflammatory disorder in patients with COVID-19, which may be linked to severe dysregulation of NCS. In this study, we present a series of complexes with cholinergic agonists that can potentially prevent SARS-CoV-2 Spike glycoprotein from binding to nAChRs, avoiding dysregulation of the NCS and moderating the symptoms and clinical manifestations of COVID-19. If our hypothesis is verified by in vitro and in vivo studies, repurposing agents currently approved for smoking cessation and neurological conditions could provide the scientific community with a therapeutic option in severe COVID-19.

[Electroacupuncture at "Ganshu" (BL18) and "Yanglingquan" (GB34) alleviates hepatic ischemia-reperfusion injury by inhibiting translocation and release of high mobility group protein 1 in rats].

OBJECTIVE: To explore the protective effect of electroacupuncture (EA) on hepatic ischemia-reperfusion injury (HIRI) and the expression of high mobility group protein 1 (HMGB1) in liver tissues in rats. METHODS: A total of 40 male SD rats were randomly divided into 4 groups, namely sham control, HIRI model, "Ganshu"(BL18) -"Yanglingquan"(GB34) and non-acupoint group, with 10 rats in each group. The HIRI model was induced by blocking the arteries, veins and bile ducts supplying the middle and left lobes of the liver for 1 h, and reperfusion for 4 h to induce an area of about 70% HIRI. EA was applied to bila-teral BL18 and GB34, or non-acupoints about 6-8 mm to the bilateral BL18 for 30 min before modeling. Serum alanine transaminase (ALT) and aspartate aminotransferase (AST) levels were measured by using an automatic biochemical analyzer. Serum tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and HMGB1 levels were assayed by ELISA. Hematoxylin - eosin (H.E.) staining was used to observe histopathological changes of the liver tissue by using tissue injury scaling (0-3 scores). The expression of HMGB1 protein in liver tissues was detected by immunohistochemical staining, Western blot and PCR, separately. RESULTS: Following modeling and compared with the sham group, the levels of serum ALT, AST, TNF-α, IL-6, and HMGB1 contents, the number of HMGB1 immunoreaction (IR)-positive cells, and HMGB1 protein and mRNA were significantly increased (P＜0.01). After the treatment, the contents of serum ALT, AST, TNF-α, IL-6, and HMGB1, liver HMGB1 IR-positive cells, protein and mRNA were considerably down-regulated in the BL18-GB34 group (P<0.05), rather than in the non-acupoint group (P>0.05) in contrast to the model group. H.E. stain showed a higher liver injury score in the model group than in the sham group (P<0.01), and a lower liver injury score in the BL18-GB34 group (not the non-acupoint group) relevant to the model group (P<0.05). CONCLUSION: EA of BL18 and GB34 points has a protective effect on ischemic liver injury in rats with HIRI, which may be associated with its functions in inhibiting the migration and release of HMGB1 from the nucleus to the cytoplasm and in down-regulating the expression of inflammatory factors.

Decreased expression of prohibitin 1 mediates high-mobility group protein 1-induced pulmonary artery endothelial cell injury. / PHB1表达下调介导HMGB1ä¿ƒè‚ºåŠ¨è„‰å† çš®ç»†èƒžæŸä¼¤.

OBJECTIVES: There is a significant increase of high-mobility group protein B1 (HMGB1) in plasma levels of patients with pulmonary hypertension, but the biological significance is still unclear. Anti-proliferative protein 1 (prohibitin 1, PHB1) is an important protein that maintains the homeostasis of vascular cells. This study aimed to investigate the effect of HMGB1 on pulmonary artery endothelial cells and the role of PHB1. METHODS: In vivo experiment: A rat model of pulmonary hypertension induced by monocrotaline (MCT) was constructed. The right ventricular systolic pressure (RVSP), and the weight ratio of right ventricle to left ventricle plus ventricular septum were used to evaluate the success of model. ELISA was used to detect the level of HMGB1 in rat's plasma. Western blotting was used to detect the level of PHB1 in rat's lung tissues. CD31 immunofluorescence was used to detect the integrity of pulmonary vascular endothelium. In vitro experiments: Pulmonary artery endothelial cell (PAEC) was incubated with HMGB1 to observe the effect of HMGB1 on PAEC injury. Overexpression and knockdown of PHB1 were conducted, and the role of PHB1 was investigated by detecting the levels of reative oxygen species and cytochrome c (cyto-c), and the activation of caspase-3. RESULTS: Compared with the control group, the level of HMGB1 in the plasma of rats with pulmonary hypertension was significantly increased (P<0.05), and the expression of PHB1 in the lung tissue was decreased accompanied with endothelial dysfunction (P<0.05); HMGB1 incubation damaged the pulmonary artery endothelium and down-regulated PHB1 expression (P<0.05), while overexpression of PHB1 reduced the PAEC damage and oxidative stress induced by HMGB1 (P<0.05). Meanwhile, PHB1 reduced HMGB1-induced cyto-c expression and caspase-3 cleavage by inhibiting oxidative stress (P<0.05). CONCLUSIONS: The down-regulation of PHB1 expression mediates HMGB1-induced PAEC injury, which is related to the induction of oxidative stress, the increase of cyto-c release, and the promotion of caspase-3 cleavage.

Clinical effect of Changweishu on gastrointestinal dysfunction in patients with sepsis.

OBJECTIVE: To investigate Changweishu's clinical effect on gastrointestinal dysfunction in patients with sepsis. METHODS: Fifty patients with gastrointestinal dysfunction and sepsis were randomly divided into treatment and control groups. The control group patients received routine Western medicine treatments (meropenem, noradrenaline, glutamine glue, Bifidobacterium lactis triple-strain tablet), and the treatment group patients received routine Western medicine treatment combined with Changweishu. Treatments in both groups lasted 7 days. Changes in APACHE II score, gastrointestinal dysfunction score, serum levels of diamine oxidase (DAO), D-lactic acid, inflammatory factors (tumor necrosis factor (TNF)-α, interleukin (IL)-6, and high-mobility group box 1 (HMGB-1)), and the incidence of multiple organ dysfunction syndrome (MODS) and mortality were observed. RESULTS: After treatment, APACHE II score, gastrointestinal dysfunction score, and DAO, D-lactic acid, TNF-α, IL-6, and HMGB-1 levels decreased significantly in both groups, but the decrease was more significant in the treatment group than in the control group. The incidence of MODS and mortality were significantly lower in the treatment group than in the control group. CONCLUSION: The addition of Changweishu to routine Western treatments can improve gastrointestinal function in patients with sepsis and gastrointestinal dysfunction, as well as decreasing the incidence of MODS and mortality and improving patient prognosis.

Long noncoding RNA MALAT1 sponges miR-129-5p to regulate the development of bronchopulmonary dysplasia by increasing the expression of HMGB1.

OBJECTIVE: To explore the function and mechanism of long noncoding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1) in bronchopulmonary dysplasia. METHODS: Alveolar epithelial cell line BEAS-2B was used as the cell model. The role of MALAT1 and microRNA miR-129-5p in regulating cellular viability and migration were examined by using the CCK-8 and Transwell assays, respectively, in vitro. The luciferase reporter assay and real-time (RT)-PCR were performed to confirm that miR-129-5p was a target of MALAT1. ELISA was conducted to validate MALAT1 and show that miR-129-5p regulated the gene encoding high-mobility group protein 1 (HMGB1). RESULTS: Overexpression of MALAT1 significantly promoted cellular viability, whereas miR-129-5p had the opposite effect. miR-129-5p was shown to be a target of MALAT1, and HMGB1 could be upregulated by MALAT1 overexpression or miR-129-5p inhibition. CONCLUSION: MALAT1 reduced the expression of miR-129-5p, promoting the viability of cells and blocking the development of bronchopulmonary dysplasia. In addition, MALAT1 increased the expression of HMGB1, which contributed to inflammation as the disease progressed.

Electroacupuncture at "Ganshu" (BL18) and "Yanglingquan" (GB34) alleviates hepatic ischemia-reperfusion injury by inhibiting translocation and release of high mobility group protein 1 in rats / 针刺研究

OBJECTIVE: To explore the protective effect of electroacupuncture (EA) on hepatic ischemia-reperfusion injury (HIRI) and the expression of high mobility group protein 1 (HMGB1) in liver tissues in rats. METHODS: A total of 40 male SD rats were randomly divided into 4 groups, namely sham control, HIRI model, "Ganshu"(BL18) -"Yanglingquan"(GB34) and non-acupoint group, with 10 rats in each group. The HIRI model was induced by blocking the arteries, veins and bile ducts supplying the middle and left lobes of the liver for 1 h, and reperfusion for 4 h to induce an area of about 70% HIRI. EA was applied to bila-teral BL18 and GB34, or non-acupoints about 6-8 mm to the bilateral BL18 for 30 min before modeling. Serum alanine transaminase (ALT) and aspartate aminotransferase (AST) levels were measured by using an automatic biochemical analyzer. Serum tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and HMGB1 levels were assayed by ELISA. Hematoxylin - eosin (H.E.) staining was used to observe histopathological changes of the liver tissue by using tissue injury scaling (0-3 scores). The expression of HMGB1 protein in liver tissues was detected by immunohistochemical staining, Western blot and PCR, separately. RESULTS: Following modeling and compared with the sham group, the levels of serum ALT, AST, TNF-α, IL-6, and HMGB1 contents, the number of HMGB1 immunoreaction (IR)-positive cells, and HMGB1 protein and mRNA were significantly increased (P＜0.01). After the treatment, the contents of serum ALT, AST, TNF-α, IL-6, and HMGB1, liver HMGB1 IR-positive cells, protein and mRNA were considerably down-regulated in the BL18-GB34 group (P0.05) in contrast to the model group. H.E. stain showed a higher liver injury score in the model group than in the sham group (P<0.01), and a lower liver injury score in the BL18-GB34 group (not the non-acupoint group) relevant to the model group (P<0.05). CONCLUSION: EA of BL18 and GB34 points has a protective effect on ischemic liver injury in rats with HIRI, which may be associated with its functions in inhibiting the migration and release of HMGB1 from the nucleus to the cytoplasm and in down-regulating the expression of inflammatory factors.

Study on Mechanism of Taoren Chengqitang in Regulating Intestinal Myoelectrical Activity and Microenvironment Homeostasis in Intestinal Sepsis Rats Based on HMGB1/TLR4/NF-κB Pathway / 中国实验方剂学杂志

Objective:To study the mechanism of Taoren Chengqitang in regulating intestinal myoelectric activity and microenvironment homeostasis in intestinal sepsis rats based on high mobility group protein 1(HMGB1)/Toll-like receptor 4(TLR4)/nuclear factor -κB(NF-κB) pathway. Method:The 60 SD rats were randomly divided into sham operation group, model group, glycyrrhizic acid (HMGB1 inhibitor, 0.03 g·kg-1) group, Taoren Chengqitang group (10 g·kg-1), glycyrrhizic acid+Taoren Chengqitang group (0.03 g·kg-1+10 g·kg-1), with 12 rats in each group. Except the sham operation group, the other groups established intestinal sepsis rat models, each group was treated with medicine, hematoxylin-eosin (HE) staining was used to detect the histopathological changes of small intestinal mucosa in rats of each group, the changes of mucosal thickness and villus height were compared, the levels of secretory immunoglobulin A (sIgA), diamine oxidase (DAO) and D-lactic acid in intestinal mucosa of rats were detected by kit, the intestinal myoelectrical activity of rats in each group was measured, the slow wave frequency and amplitude of small intestinal smooth muscle were compared, the intestinal flora of rats in each group was detected, the contents of E. coli, Bifidobacterium and Lactobacillus were compared, and the expressions of HMGB1/TLR4/NF-κB pathway proteins HMGB1, TLR4, MyD88 and NF-κB p65 in small intestinal tissues were detected by Western blot. Result:Compared with sham operated group, the villus height, mucosal thickness, sIgA content, slow wave frequency and amplitude of smooth muscle, Bifidobacterium and Lactobacillus contents in intestinal mucosa of model group rats were significantly decreased, and serum DAO and D-lactic acid levels, intestinal E. coli content, intestinal tissue HMGB1, TLR4, MyD88 and NF-κB p65 proteins were significantly increased (P<0.05). Compared with the model group, the villus height, mucosal thickness, sIgA content, slow wave frequency and amplitude of smooth muscle, Bifidobacterium and Lactobacillus contents in intestinal mucosa of the Taoren Chengqitang group, glycyrrhizic acid group, and glycyrrhizic acid + Taoren Chengqitang group were significantly increased, and serum DAO and D-lactic acid levels, intestinal E. coli content, intestinal tissue HMGB1, TLR4, MyD88 and NF-κB p65 proteins were significantly decreased (P<0.05). Compared with the Taoren Chengqitang group and the glycyrrhizic acid group, the villus height, mucosal thickness, sIgA content, slow wave frequency and amplitude of smooth muscle, Bifidobacterium and Lactobacillus contents in intestinal mucosa of glycyrrhizic acid+Taoren Chengqitang group were significantly increased, and serum DAO and D-lactic acid levels, intestinal E. coli content, intestinal tissue HMGB1, TLR4, MyD88 and NF-κB p65 proteins were significantly decreased, the differences were statistically significant (P<0.05). Conclusions:Taoren Chengqitang can alleviate intestinal mucosal injury, regulate intestinal myoelectrical activity and microenvironment homeostasis, restore intestinal function and maintain flora balance in intestinal sepsis rats, which may be achieved by down-regulating HMGB1/TLR4/NF-κB pathway.

Inflammatory mechanism of chlorpyrifos-induced lung injury in rats / 中国职业医学

OBJECTIVE: To investigate the inflammatory mechanism of chlorpyrifos-induced lung injury in rats. METHODS: Specific pathogen free SD rats were randomly divided into control and low-, medium-and high-dose groups, 8 rats in each group. Rats were exposed to 48% chlorpyrifos by continuous oral administration for 28 consecutive days, once a day, with the doses of 0.0, 4.1, 8.2 and 16.3 mg/kg body mass. After the exposure, the enzyme-linked immunosorbent assay was used to detect the level of tumor necrosis factor-α(TNF-α) and interleukin-1(IL-1) in rat lung tissue. The expression of high mobility group protein-1(HMGB1) and nuclear transcription factor-κB(NF-κB) was detected by immunohistochemistry and Western blotting, respectively. RESULTS: The activity of the rats decreased after exposure in the low-, medium-and high-dose groups compared with the control group. The rats in the medium and high dose groups increased salivation, nasal secretions, and difficulty breathing. The rats in the high dose group also developed diarrhea, muscle tremor, unstable gait, as well as muscarinic and nicotinic symptoms. After the exposure, the lung tissues of rats in the low-, medium-and high-dose groups showed different degrees of inflammation, which increased in a dose-dependent manner; the body mass of rats in the 3 dose groups was lower than that in the control group(all P values were <0.05), and the body mass of rats decreased with the increase of chlorpyrifos dose(all P values were <0.05). The levels of TNF-α, IL-1 and the relative expression of HMGB1, NF-κB were higher in the 3 dose groups than those in the control group(all P values were <0.05), and the levels of TNF-α, IL-1 and the relative expression of HMGB1 increased with the increasing exposure dose(all P values were <0.05). CONCLUSION: Chlorpyrifos can activate the NF-κB signaling pathway and eventually induce the macrophages to secrete large amount of TNF-α and IL-1, resulting in lung inflammation and injury in rats. The effect of chlorpyrifos has a dose-effect relationship.