PKCα-LSD1-NF-κB-Signaling Cascade Is Crucial for Epigenetic Control of the Inflammatory Response.

The inflammatory response mediated by nuclear factor κB (NF-κB) signaling is essential for host defense against pathogens. Although the regulatory mechanism of NF-κB signaling has been well studied, the molecular basis for epigenetic regulation of the inflammatory response is poorly understood. Here we identify a new signaling axis of PKCα-LSD1-NF-κB, which is critical for activation and amplification of the inflammatory response. In response to excessive inflammatory stimuli, PKCα translocates to the nucleus and phosphorylates LSD1. LSD1 phosphorylation is required for p65 binding and facilitates p65 demethylation, leading to enhanced stability. In vivo genetic analysis using Lsd1SA/SA mice with ablation of LSD1 phosphorylation and chemical approaches in wild-type mice with inhibition of PKCα or LSD1 activity show attenuated sepsis-induced inflammatory lung injury and mortality. Together, we demonstrate that the PKCα-LSD1-NF-κB signaling cascade is crucial for epigenetic control of the inflammatory response, and targeting this signaling could be a powerful therapeutic strategy for systemic inflammatory diseases, including sepsis.

Antiseptic Functions of CGK012 against HMGB1-Mediated Septic Responses.

High mobility group box 1 (HMGB1), a protein with important functions, has been recognized as a potential therapeutic target for the treatment of sepsis. One possible mechanism for this is that inhibiting HMGB1 secretion can exert antiseptic effects, which can restore the integrity of the vascular barrier. (7S)-(+)-cyclopentyl carbamic acid 8,8-dimethyl-2-oxo-6,7-dihydro-2H,8H-pyrano[3,2-g]chromen-7-yl-ester (CGK012) is a newly synthesized pyranocoumarin compound that could function as a novel small-molecule inhibitor of the Wnt/ß-catenin signaling pathway. However, no studies have yet determined the effects of CGK012 on sepsis. We investigated the potential of CGK012 to attenuate the excessive permeability induced by HMGB1 and enhance survival rates in a mouse model of sepsis with reduced HMGB1 levels following lipopolysaccharide (LPS) treatment. In both LPS-stimulated human endothelial cells and a mouse model exhibiting septic symptoms due to cecal ligation and puncture (CLP), we assessed proinflammatory protein levels and tissue damage biomarkers as indicators of reduced vascular permeability. CGK012 was applied after induction in human endothelial cells exposed to LPS and the CLP-induced mouse model of sepsis. CGK012 effectively mitigated excessive permeability and suppressed HMGB1 release, resulting in improved vascular stability, decreased mortality, and enhanced histological conditions in the mouse model of CLP-induced sepsis. In conclusion, our findings indicate that CGK012 treatment in mice with CLP-induced sepsis diminished HMGB1 release and increased the survival rate, suggesting its potential as a pharmaceutical intervention for sepsis.

Integrative Profiling of Lysine Acylome in Sepsis-Induced Liver Injury.

Sepsis is one of the life-threatening diseases worldwide. Despite the continuous progress in medicine, the specific mechanism of sepsis remains unclear. A key strategy of pathogens is to use post-translational modification to modulate host factors critical for infection. We employed global immunoprecipitation technology for lysine acetylation (Kac), succinylation (Ksu), and malonylation (Kmal) for the first global lysine acylation (Kacy) analysis in a cecum ligation and puncture (CLP) model in mouse. This was performed to reveal the pathogenic mechanism of integrative Kacy and the changes in modification sites. In total, 2230 sites of 1,235 Kac proteins, 1,887 sites of 433 Ksu proteins, and 499 sites of 276 Kmal proteins were quantified and normalized by their protein levels. We focused on 379 sites in 219 upregulated proteins as the integrative Kacy sites of Kac, Ksu, and Kmal on the basis of sirtuins decreased in the CLP group. KEGG pathway analysis of integrative Kacy in 219 upregulated proteins revealed three central metabolic pathways: glycolysis/gluconeogenesis, pyruvate metabolism, and tricarboxylic acid cycle. These findings reveal the key pathogenic mechanism of integrative PTM alteration in terms of the decreased sirtuins level and provide an important foundation for an in-depth study of the biological function of Kacy in sepsis.

Global Profiling of Lysine Acetylation and Lactylation in Kupffer Cells.

Among the various cell types that constitute the liver, Kupffer cells (KCs) are responsible for the elimination of gut-derived foreign products. Protein lysine acetylation (Kac) and lactylation (Kla) are dynamic and reversible post-translational modifications, and various global acylome studies have been conducted for liver and liver-derived cells. However, no such studies have been conducted on KCs. In this study, we identified 2198 Kac sites in 925 acetylated proteins and 289 Kla sites in 181 lactylated proteins in immortalized mouse KCs using global acylome technology. The subcellular distributions of proteins with Kac and Kla site modifications differed. Similarly, the specific sequence motifs surrounding acetylated or lactylated lysine residues also showed differences. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to better understand the differentially expressed proteins in the studies by Kac and Kla. In the newly identified Kla, we found K82 lactylation in the high-mobility group box-1 protein in the neutrophil extracellular trap formation category using KEGG enrichment analyses. Here, we report the first proteomic survey of Kac and Kla in KCs.

Protective Effects of Cirsilineol against Lipopolysaccharide-Induced Inflammation; Insights into HO-1, COX-2, and iNOS Modulation.

In this study, the potential protective effects of cirsilineol (CSL), a natural compound found in Artemisia vestita, were examined on lipopolysaccharide (LPS)-induced inflammatory responses. CSL was found to have antioxidant, anticancer, and antibacterial properties, and was lethal to many cancer cells. We assessed the effects of CSL on heme oxygenase (HO)-1, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) in LPS-activated human umbilical vein endothelial cells (HUVECs). We also examined the effects of CSL on the expression of iNOS, tumor necrosis factor (TNF)-α, and interleukin (IL)-1ß in the pulmonary histological status of LPS-injected mice. The results showed that CSL increased HO-1 production, inhibited luciferase-NF-κB interaction, and reduced COX-2/PGE2 and iNOS/NO levels, leading to a decrease in signal transducer and activator of transcription (STAT)-1 phosphorylation. CSL also enhanced the nuclear translocation of Nrf2, elevated the binding activity between Nrf2 and antioxidant response elements (AREs), and reduced IL-1ß expression in LPS-treated HUVECs. We found that CSL's suppression of iNOS/NO synthesis was restored by inhibiting HO-1 through RNAi. In the animal model, CSL significantly decreased iNOS expression in the pulmonary biostructure, and TNF-α level in the bronchoalveolar lavage fluid. These findings indicate that CSL has anti-inflammatory properties by controlling iNOS through inhibition of both NF-κB expression and p-STAT-1. Therefore, CSL may have potential as a candidate for developing new clinical substances to treat pathological inflammation.

Procyanidin B2 Attenuates Sepsis-Induced Acute Lung Injury via Regulating Hippo/Rho/PI3K/NF-κB Signaling Pathway.

Acute lung injury (ALI) is a frequent and challenging aspect of sepsis that currently lacks effective treatments. Procyanidin B2 (PB2) has anti-inflammatory and antioxidant properties. The aim of this study was to determine the effectiveness and mechanism of action of PB2 in treating sepsis-induced ALI using animal experiments. A sepsis-induced ALI mouse model was used by administering lipopolysaccharide (LPS) and then evaluating the levels of inflammatory cytokines and lung injury through measurements of cytokine levels using enzyme-linked immunosorbent assay (ELISA), Western blot and real-time PCR, as well as by the examination of relevant signaling pathways. The animal experiments showed that PB2 protected the lungs from injury caused by LPS and reduced the levels of various inflammatory cytokines in both the serum and lung tissue. Western blot analysis showed that PB2 reduced the expression of TLR4/NF-κB and increased the expression of PI3K/Akt, and also inhibited the Hippo and Rho signaling pathways. The results of the study showed that PB2 helps to treat sepsis-induced ALI by controlling cytokine storms and reducing inflammation by altering the expressions of the TLR4/NF-κB, PI3K/Akt, Hippo and Rho signaling pathways. This research provides a foundation for the further investigation of PB2's mechanism and its potential use in treating sepsis.

Therapeutic Effects of Cornuside on Particulate Matter-Induced Lung Injury.

Particulate matter (PM) is a mixture comprising both organic and inorganic particles, both of which are hazardous to health. The inhalation of airborne PM with a diameter of ≤2.5 µm (PM2.5) can cause considerable lung damage. Cornuside (CN), a natural bisiridoid glucoside derived from the fruit of Cornus officinalis Sieb, exerts protective properties against tissue damage via controlling the immunological response and reducing inflammation. However, information regarding the therapeutic potential of CN in patients with PM2.5-induced lung injury is limited. Thus, herein, we examined the protective properties of CN against PM2.5-induced lung damage. Mice were categorized into eight groups (n = 10): a mock control group, a CN control group (0.8 mg/kg mouse body weight), four PM2.5+CN groups (0.2, 0.4, 0.6, and 0.8 mg/kg mouse body weight), and a PM2.5+CN group (0.2, 0.4, 0.6, and 0.8 mg/kg mouse body weight). The mice were administered with CN 30 min following intratracheal tail vein injection of PM2.5. In mice exposed to PM2.5, different parameters including changes in lung tissue wet/dry (W/D) lung weight ratio, total protein/total cell ratio, lymphocyte counts, inflammatory cytokine levels in the bronchoalveolar lavage fluid (BALF), vascular permeability, and histology were examined. Our findings revealed that CN reduced lung damage, the W/D weight ratio, and hyperpermeability caused by PM2.5. Moreover, CN reduced the plasma levels of inflammatory cytokines produced because of PM2.5 exposure, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and nitric oxide, as well as the total protein concentration in the BALF, and successfully attenuated PM2.5-associated lymphocytosis. In addition, CN substantially reduced the expression levels of Toll-like receptors 4 (TLR4), MyD88, and autophagy-related proteins LC3 II and Beclin 1, and increased protein phosphorylation of the mammalian target of rapamycin (mTOR). Thus, the anti-inflammatory property of CN renders it a potential therapeutic agent for treating PM2.5-induced lung injury by controlling the TLR4-MyD88 and mTOR-autophagy pathways.

Jujuboside B post-treatment attenuates PM2.5-induced lung injury in mice.

Fine particulate matter (PM2.5) is an air pollutant that causes severe lung injury. We investigated the effects of Jujuboside B (JB), a component of Zizyphi Spinosi Semen, on lung toxicity caused by PM2.5, and we identified the mechanism of its protective effect. Lung injury in an animal model was induced by intratracheal administration of a PM2.5 suspension. After 2 days of PM2.5 pretreatment, mice were administered JB via the tail vein three times over a 2-day period. JB significantly reduced the histological lung damage as well as the lung wet/dry weight ratio. JB also considerably reduced PM2.5-induced autophagy dysfunction, apoptosis, inflammatory cytokine levels, and the number of PM2.5-induced lymphocytes in the bronchial alveolar fluid. We conclude that by regulating TLR2, 4-MyD88, and mTOR-autophagy pathways, JB exerts a protective effect on lung injury. Thus, JB can be used as a potential therapeutic agent for PM2.5-induced lung damage.

The Neuroprotective Effects of Arecae Pericarpium against Glutamate-Induced HT22 Cell Cytotoxicity.

Arecae Pericarpium has been found to exert anti-migraine, antidepressant, and antioxidative effects. However, the mechanisms involved are unclear. This study explored the possibility that Arecae Pericarpium ethanol extract (APE) exerts neuroprotective effects against oxidative stress-induced neuronal cell death. Since glutamate excitotoxicity has been implicated in the pathogenesis and development of several neurodegenerative disorders, we explored the mechanisms of action of APE on oxidative stress-induced by glutamate. Our results revealed that pretreatment with APE prevents glutamate-induced HT22 cell death. APE also reduced both the levels of intracellular reactive oxygen species and the apoptosis of cells, while maintaining glutamate-induced mitochondrial membrane potentials. Western blotting showed that pretreatment with APE facilitates the upregulation of phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) phosphorylation; the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf-2); and the production of antioxidant enzymes, including catalase, glutamate-cysteine ligase catalytic subunits, NAD(P)H quinone oxidoreductase 1, and heme oxygenase (HO)-1. The administration of LY294002, a PI3K/Akt inhibitor, attenuated the neuroprotective effects of APE on oxidative stress-induced neuronal cell damage. This allowed us to infer that the protective effects of APE on oxidative damage to cells can be attributed to the PI3K/Akt-mediated Nrf-2/HO-1 signaling pathway.

Inhibitory effects of aloin on lipopolysaccharide-induced severe inflammatory responses.

Aloin is the main anthraquinone glycoside from Aloe species. Here, the anti-inflammatory functions of aloin against lipopolysaccharide (LPS)-induced vascular inflammatory responses were tested in endothelial cells or mice such as permeability, expressions of cell adhesion molecule (CAM), migration of leukocytes and lethality. Aloin was found to inhibit LPS-induced barrier disruption, CAM expression, and neutrophil adhesion/transendothelial migration to endothelial cells. Furthermore, aloin inhibited LPS-induced hyperpermeability, leukocyte migration, lethality in vivo. These results suggest that aloin has anti-inflammatory activities against LPS, thereby supporting its usefulness as a treatment for vascular inflammatory.

Cirsilineol Treatment Attenuates PM2.5-Induced Lung Injury in Mice.

Ultrafine particulate matter with less than 2.5 µm diameter (PM2.5) is an air pollutant that causes severe lung damage. Currently, effective treatment and preventive methods for PM2.5-induced lung damage are limited. Cirsilineol (CSL) is a small natural compound isolated from Artemisia vestita. In this study, the efficacy of CSL on PM2.5-induced lung toxicity was tested, and its mechanism was identified. Lung injury was caused by intratracheal administration of PM2.5 suspension in animal models. Two days after PM2.5 pretreatment, CSL was injected via mouse tail vein for two days. The effects of CSL on PM2.5-induced lung damage, autophagy, apoptosis, and pulmonary inflammation in a mouse model and their mechanisms were investigated. CSL significantly suppressed histological lung damage and lung wet/dry weight proportion. CSL also significantly reduced PM2.5-induced autophagy dysfunction, apoptosis, lymphocyte suppression, and inflammatory cytokine levels in bronchoalveolar fluid (BALF). Furthermore, CSL increased mammalian target of rapamycin (mTOR) phosphorylation and significantly inhibited the expression of Toll-like receptors (TLR) 2 and 4, MyD88, and the autophagy proteins, Beclin1 and LC3II. Thus, CSL exerts protective effects on pulmonary damage by regulating mTOR and TLR2,4-myD88 autophagy pathways. Therefore, CSL can be used as an effective treatment for PM2.5-induced lung damage.

Benzoylpaeoniflorin Activates Anti-Inflammatory Mechanisms to Mitigate Sepsis in Cell-Culture and Mouse Sepsis Models.

Xuebijing injection (XBJI) (comprising of five herbs) is a widely used traditional Chinese medicine for sepsis treatment. However, the bioactive components of XBJI and the mechanisms responsible for its sepsis-mitigating action have not been experimentally determined. One of the main bioactive compounds in XBJI-benzoylpaeoniflorin (BPF)-inhibits the expressions of key mediators of inflammation such as nuclear factor kappa B (NF-κB), cyclooxygenase-1 (COX-1), and COX-2. However, its effects on sepsis have not been determined yet. Therefore, here, we investigated the immunomodulatory effect of BPF on severely inflamed endothelial cells, THP-1 macrophages, peritoneal macrophages, and mice. Human umbilical vein endothelial cells (HUVECs) and THP-1-macrophages were activated using lipopolysaccharide (LPS) after pretreatment with BPF. Subsequently, changes in the expression profiles of pro-inflammatory molecules including inducible nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 were determined using quantitative real-time polymerase chain reaction (qPCR) and Western blot analysis. Furthermore, we monitored the phosphorylation of NF-kB and mitogen-activated protein kinases (MAPKs) to determine their activation levels. Using the LPS-induced mouse model of sepsis, we studied the effects of BPF on inflammatory cytokine production, pulmonary histopathology, and survival rates. Finally, we evaluated whether BPF protects against cecal ligation and puncture (CLP)-induced sepsis, as it closely mimics human sepsis. BPF pretreatment inhibited LPS-induced increase in mRNA and protein levels of iNOS, TNF-α, and IL-6 in HUVECs and THP-1-macrophages. It also suppressed LPS-mediated phosphorylation of p65, p38, JNK, and ERK. Mice with LPS-induced-sepsis who were treated with BPF had lower serum levels of IL-6, TNF-α, IL-1ß, CXCL1, and CXCL2 than the control mice treated with BPF. Histopathology revealed that BPF treatment alleviated LPS-induced lung damage. In addition, in mice given a lethal dose of LPS, BPF treatment showed a dose-dependent improvement in survival rates. BPF treatment dose-dependently inhibited the LPS-induced IL-6, TNF-α, and CXCL1 production in peritoneal macrophages. BPF treatment also dose-dependently improved the survival rates in mice with CLP-induced sepsis. These results show that BPF alleviates LPS-stimulated septic conditions and protects mice from CLP-induced sepsis. Our research marks BPF as a potential drug in the treatment of sepsis and various inflammatory diseases.

Anti-Septic Functions of Cornuside against HMGB1-Mediated Severe Inflammatory Responses.

High mobility group box 1 (HMGB1) is acknowledged to have critical functions; therefore, targeting this protein may have therapeutic effects. One example is potential antiseptic activity obtained by suppressing HMGB1 secretion, leading to the recovery of vascular barrier integrity. Cornuside (CN), which is a product extracted from the fruit of Cornusofficinalis Seib, is a natural bis-iridoid glycoside with the therapeutic effects of suppressing inflammation and regulating immune responses. However, the mechanism of action of CN and impact on sepsis is still unclear. We examined if CN could suppress HMGB1-induced excessive permeability and if the reduction of HMGB1 in response to LPS treatment increased the survival rate in a mouse model of sepsis. In human endothelial cells stimulated by LPS and mice with septic symptoms of cecal ligation and puncture (CLP), we examined levels of proinflammatory proteins and biomarkers as an index of tissue damage, along with decreased vascular permeability. In both LPS-treated human umbilical vein endothelial cells (HUVECs) and the CLP-treated mouse model of sepsis, we applied CN after the induction processes were over. CN suppressed excessive permeability and inhibited HMGB1 release, leading to the amelioration of vascular instability, reduced mortality, and improved histological conditions in the CLP-induced septic mouse model. Overall, we conclude that the suppressed release of HMGB1 and the increased survival rate of mice with CLP-induced sepsis caused by CN may be an effective pharmaceutical treatment for sepsis.

Inhibitory Activities of Rare Ginsenoside Rg4 on Cecal Ligation and Puncture-Induced Sepsis.

Sepsis is an uncontrolled response to inflammatory infection and is associated with high levels of mortality and morbidity. Rg4 is a rare ginsenoside mainly found in the leaves of Panax ginseng C. A. Meyer and the major protopanaxatriol-type ginsenoside of black ginseng. In this study, we determined whether Rg4 affects cecal ligation and puncture (CLP)-induced sepsis. Animals were separated into the following six groups: control group, CLP-operated group, CLP plus maslinic acid (MA), and CLP plus Rg4 (5, 10, or 15 mg/kg). Survival rate, body weight changes, inflammatory cytokines, and histological analyses were assessed. Human endothelial cells were activated with the high-mobility group box 1 (HMGB1) protein and Rg4. Cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Enzyme-linked immunosorbent assay (ELISA) and Western blot analysis were used to assess inflammation and gene expression, respectively. After CLP surgery, the Rg4-administered group exhibited a higher survival rate and body weight compared with the untreated control group. Rg4 treatment reduced cytokine levels, including tumor necrosis factor (TNF)-α and interleukin (IL)-1ß, as well as nitric oxide (NO) levels and renal inflammation. After Rg4 treatment of HMGB1-activated cells, the expressions of toll-like receptor (TLR) 4 and TNF-α were decreased, and the activation of phosphoinositide 3-kinase (PI3K)/AKT signaling increased cell viability. In summary, Rg4 inhibited inflammation and exhibited a protective effect against CLP-induced sepsis, thereby reinforcing cell survival against septic responses.

Anti-Inflammatory Effect of Sparstolonin B through Inhibiting Expression of NF-κB and STAT-1.

Sparstolonin B (SsnB), which is found in Sparganium stoloniferum, prevents the synthesis of inflammatory mediators and is related to functional pathways of survival. In this study, we assessed the possible protective functions of SsnB on lipopolysaccharide (LPS)-induced inflammatory responses. We determined the functions of SsnB on controlling heme oxygenase (HO)-1, cyclooxygenase (COX-)2, and inducible nitric oxide synthase (iNOS) in LPS-activated human umbilical vein endothelial cells (HUVECs). Furthermore, the distinct function of SsnB on the expression of iNOS and well-known pro-inflammatory mediators, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1ß, were assessed in the pulmonary histological status of LPS-injected mice. SsnB upregulated the HO-1 production, inhibited luciferase-NF-κB interaction, and lowered COX-2/PGE2 and iNOS/NO, which lead to the reduction of STAT-1 phosphorylation. Moreover, SsnB enhanced the nuclear translocation of Nrf2, elevated the binding activity between Nrf2 and antioxidant response elements (AREs), and weakened IL-1ß expression on LPS-treated HUVECs. SsnB-suppressed iNOS/NO synthesis was restored by the process of the RNAi inhibition of HO-1. In experiment with an LPS-injected animal model, SsnB remarkably decreased the iNOS expression in the pulmonary biostructure and TNF-α level in the bronchoalveolar lavage fluid (BALF). Therefore, these results demonstrate that SsnB is responsible for inflammation ameliorative activity by controlling iNOS through inhibition of both NF-κB expression and p-STAT-1. Therefore, SsnB could be a candidate for promoting novel clinical substances to remedy pathologic inflammation.

Barrier protective functions of hederacolchiside-E against HMGB1-mediated septic responses.

The role of high mobility group box 1 (HMGB1) has been recognized as important, and suppression of HMGB1 release and restoration of vascular barrier integrity are regarded as potentially promising therapeutic strategies against sepsis. Hederacolchiside-E (HCE), namely 3-O-{α-L-rhamnopyranosyl (1→2)-[ß-D-glucopyranosyl(1→4)]-α-L-arabinopyranosyl}-28-O-[α-L-rhamnopyranosyl (1→4)-ß-D-glucopyranosyl(1→6)-ß-D-glucopyranosyl ester, is a bidesmosidic oleanane saponin first isolated in 1970 from the leaves of Hedera colchica. We tested our hypothesis that HCE inhibits HMGB1-induced vascular hyperpermeability and thereby increases the survival of septic mouse model from suppression of HMGB1 release upon lipopolysaccharide (LPS)-stimulation. In LPS-activated human endothelial cells and a sepsis mouse model by cecal ligation and puncture (CLP), antiseptic activity of HCE was investigated from suppression of vascular permeability, pro-inflammatory proteins, and tissue injury markers. Post-treatment of HCE significantly suppressed HMGB1 release both in LPS-activated human endothelial cells and the CLP-induced sepsis mouse model. HCE inhibited hyperpermeability and alleviated HMGB1-mediated vascular disruptions, and reduced sepsis-related mortality and tissue injury in mice. Our results suggest that reduction of HMGB1 release and septic mortality by HCE may be useful for the drug candidate of sepsis, indicating a possibility of successful repositioning of HCE.

Selective inhibitory effects of HYIpro-3-1 on CYP1A2 in human liver microsomes.

CYP1A2 is one of the main Cytochrome P450 enzymes in the human liver associated with the metabolism of several xenobiotics. CYP1A2 is especially involved in the metabolic activation of different procarcinogens. Therefore, the development of cancer may be inhibited by inhibiting CYP1A2 activity. Here, the inhibitory effect of HYIpro-3-1 and its derivatives on CYP1A2 activity in human liver microsomes (HLM) was studied through LC-MS/MS using a cocktail assay. Among the four compounds, HYIpro-3-1 showed the most selective and strongest inhibitory effect on CYP1A2 at IC50 values of 0.1 µM in HLMs and inhibition was confirmed using purified human CYP1A2. It was determined that inhibition is reversible because the inhibitory effect of HYIpro-3-1 is not dependent on preincubation time. HYIpro-3-1 showed a typical pattern of competitive inhibition for CYP1A2-catalyzed phenacetin O-deethylation, based on the Lineweaver-Burk plot, with a Ki value of 0.05 µM in HLMs; the secondary plot also showed a linear pattern. In our study, HYIpro-3-1 was proposed as a novel inhibitor with the capacity to selectively inhibit CYP1A activity in HLMs.

Inhibitory effects of aloin on TGFBIp-mediated septic responses.

Aloin is the major anthraquinone glycoside obtained from the Aloe species. Transforming growth factor ß-induced protein (TGFBIp) is an extracellular matrix protein and released by primary human umbilical vein endothelial cells (HUVECs) and functions as a mediator of experimental sepsis. We hypothesized that aloin could reduce TGFBIp-mediated severe inflammatory responses in HUVECs and mice. Aloin effectively inhibited lipopolysaccharide (LPS)-induced release of TGFBIp and suppressed TGFBIp-mediated septic responses. Aloin suppressed TGFBIp-induced sepsis lethality and pulmonary injury. Therefore, aloin is a potential therapeutic agent for various severe vascular inflammatory diseases, with inhibition of the TGFBIp signaling pathway as the mechanism of action. [Formula: see text].

Suppressive effects of aloin on polyphosphate-mediated vascular inflammatory responses.

Human endothelial cells-derived polyphosphate (PolyP) is one of the pro-inflammatory mediators as suggested by the previous reports. Aloin is the major anthraquinone glycoside obtained from the Aloe species and exhibits anti-inflammatory and anti-oxidative activities. Aloin inhibits PolyP-mediated barrier disruption, the expressions of cell adhesion molecules, and adhesion/migration of leukocyte to HUVEC. PolyP-induced NF-κB activation and the productions of TNF-α and IL-6 were inhibited by aloin in HUVECs. These anti-inflammatory functions of aloin were confirmed in PolyP-injected mice. In conclusion, based on the anti-inflammatory effects of aloin in PolyP-mediated septic response, aloin has therapeutic potential for various systemic inflammatory diseases.

Collismycin C reduces HMGB1-mediated septic responses and improves survival rate in septic mice.

We examined the effects of a 2,2'-bipyridine containing natural product, collismycin C on high mobility group box 1 (HMGB1, septic mediator)-mediated septic responses and survival rate in a mouse sepsis model. Collismycin C inhibited the HMGB1 release and downregulated HMGB1-mediated inflammatory responses in human endothelial cells. Collismycin C also inhibited HMGB1-induced hyperpermeability and leukocyte migration in mice. In addition, collismycin C treatment reduced CLP-induced HMGB1 release and sepsis-related mortality and pulmonary damage in vivo. Our results indicate that collismycin C is a potential therapeutic agent for the treatment of severe vascular inflammatory diseases by inhibiting HMGB1 signaling pathway.