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1.
Physiol Res ; 73(3): 381-391, 2024 07 17.
Article in English | MEDLINE | ID: mdl-39027955

ABSTRACT

Linoleic acid (LA) not only functions as an essential nutrient, but also profoundly modulates oxidative stress and inflammatory response. However, the potential mechanisms have not been adequately researched. Hence, this study examined the potential pharmacological roles of LA and the underlying mechanisms in mice with lipopolysaccharide (LPS)-associated acute liver injury (ALI). The results indicated that treatment with LA alleviated the histopathological abnormalities in the hepatic and plasma levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glutathione-S-transferase (GST) in mice with LPS exposure. In addition, LA inhibited the LPS-associated generation of proinflammatory factors, such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), and downregulated the hepatic myeloperoxidase (MPO) level. In addition, the administration of LA resulted in a reduction in hepatic malondialdehyde (MDA) levels and an elevation in liver superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT), and glutathione peroxidase (GSH-PX) levels. Further investigations revealed that LA promoted the expression of nuclear factor E2-related factor (Nrf2) and NAD(P)H: quinone oxidoreductase 1 (NQO1). In addition, the beneficial outcomes of LA on LPS-induced acute liver failure were revered when Nrf2 was pharmacologically suppressed by ML385. These experimental results demonstrated that LA supplementation attenuated LPS-associated acute hepatic impairment in mice via the activation of Nrf2.


Subject(s)
Chemical and Drug Induced Liver Injury , Linoleic Acid , Lipopolysaccharides , NF-E2-Related Factor 2 , Animals , Lipopolysaccharides/toxicity , NF-E2-Related Factor 2/metabolism , Male , Mice , Linoleic Acid/pharmacology , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/drug therapy , Chemical and Drug Induced Liver Injury/pathology , Chemical and Drug Induced Liver Injury/prevention & control , Oxidative Stress/drug effects , Liver/drug effects , Liver/metabolism , Liver/pathology
2.
Respir Res ; 25(1): 276, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39010105

ABSTRACT

BACKGROUND: The pathogenesis of acute lung injury (ALI) involves a severe inflammatory response, leading to significant morbidity and mortality. N6-methylation of adenosine (m6A), an abundant mRNA nucleotide modification, plays a crucial role in regulating mRNA metabolism and function. However, the precise impact of m6A modifications on the progression of ALI remains elusive. METHODS: ALI models were induced by either intraperitoneal injection of lipopolysaccharide (LPS) into C57BL/6 mice or the LPS-treated alveolar type II epithelial cells (AECII) in vitro. The viability and proliferation of AECII were assessed using CCK-8 and EdU assays. The whole-body plethysmography was used to record the general respiratory functions. M6A RNA methylation level of AECII after LPS insults was detected, and then the "writer" of m6A modifications was screened. Afterwards, we successfully identified the targets that underwent m6A methylation mediated by METTL3, a methyltransferase-like enzyme. Last, we evaluated the regulatory role of METTL3-medited m6A methylation at phosphatase and tensin homolog (Pten) in ALI, by assessing the proliferation, viability and inflammation of AECII. RESULTS: LPS induced marked damages in respiratory functions and cellular injuries of AECII. The m6A modification level in mRNA and the expression of METTL3, an m6A methyltransferase, exhibited a notable rise in both lung tissues of ALI mice and cultured AECII cells subjected to LPS treatment. METTL3 knockdown or inhibition improved the viability and proliferation of LPS-treated AECII, and also reduced the m6A modification level. In addition, the stability and translation of Pten mRNA were enhanced by METTL3-mediated m6A modification, and over-expression of PTEN reversed the protective effect of METTL3 knockdown in the LPS-treated AECII. CONCLUSIONS: The progression of ALI can be attributed to the elevated levels of METTL3 in AECII, as it promotes the stability and translation of Pten mRNA through m6A modification. This suggests that targeting METTL3 could offer a novel approach for treating ALI.


Subject(s)
Acute Lung Injury , Alveolar Epithelial Cells , Cell Proliferation , Methyltransferases , Mice, Inbred C57BL , PTEN Phosphohydrolase , RNA, Messenger , Animals , Acute Lung Injury/chemically induced , Acute Lung Injury/metabolism , Acute Lung Injury/genetics , Acute Lung Injury/pathology , PTEN Phosphohydrolase/metabolism , PTEN Phosphohydrolase/genetics , Methyltransferases/metabolism , Methyltransferases/genetics , Mice , Cell Proliferation/drug effects , Alveolar Epithelial Cells/metabolism , Alveolar Epithelial Cells/drug effects , Alveolar Epithelial Cells/pathology , Male , RNA, Messenger/metabolism , Cell Survival/physiology , Cell Survival/drug effects , Methylation , Adenosine/analogs & derivatives , Adenosine/metabolism , Lipopolysaccharides/toxicity , RNA Stability , Cells, Cultured
3.
Mol Biol Rep ; 51(1): 825, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023749

ABSTRACT

BACKGROUND: Systemic inflammation causes several organ damage by activating the intracellular signaling mechanisms. Heart and aorta tissues are the structures mostly affected by this situation. By examining underlying processes, this study sought to determine whether cannabidiol (CBD) may have protective effects against the cardiovascular damage brought on by lipopolysaccharide (LPS). MATERIALS AND METHODS: A total of 32 female rats were randomly allocated to one of four groups: control, lipopolysaccharide (LPS) (5 mg/kg, i.p., single dose), LPS + CBD (5 mg/kg, i.p., single dose), and CBD groups. The rats were killed six hours after receiving LPS, and tissues from the heart and aorta were taken. Histopathological and immunohistochemical analyzes were performed. Oxidative stress was evaluated biochemically by spectrophotometric method. Expression levels of genes were studied by RT-qPCR method. RESULTS: Histopathological analysis of the LPS group showed moderate hyperemia, hemorrhages, edema, inflammation, and myocardial cell damage. There was a slight to moderate increase in Cox-1, G-CSF, and IL-3 immunoexpressions, along with enhanced expressions of IL-6, Hif1α, and STAT3 genes, and decreased expressions of eNOS genes. Additionally, there were increased levels of TOS and decreased TAS levels observed biochemically. CBD treatment effectively reversed and improved all of these observed changes. CONCLUSIONS: CBD protects the heart and aorta against systemic inflammation through its antioxidant and anti-inflammatory activity via regulating IL-6, Hif1α, STAT3, and eNOS intracellular pathways.


Subject(s)
Anti-Inflammatory Agents , Antioxidants , Cannabidiol , Hypoxia-Inducible Factor 1, alpha Subunit , Interleukin-6 , Lipopolysaccharides , Nitric Oxide Synthase Type III , Oxidative Stress , STAT3 Transcription Factor , Signal Transduction , Animals , Cannabidiol/pharmacology , STAT3 Transcription Factor/metabolism , Lipopolysaccharides/toxicity , Nitric Oxide Synthase Type III/metabolism , Nitric Oxide Synthase Type III/genetics , Rats , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Antioxidants/pharmacology , Antioxidants/metabolism , Anti-Inflammatory Agents/pharmacology , Female , Signal Transduction/drug effects , Oxidative Stress/drug effects , Interleukin-6/metabolism , Interleukin-6/genetics , Inflammation/drug therapy , Inflammation/metabolism , Aorta/drug effects , Aorta/pathology , Aorta/metabolism
4.
Int J Mol Sci ; 25(13)2024 Jun 29.
Article in English | MEDLINE | ID: mdl-39000295

ABSTRACT

Olprinone (OLP) is a selective inhibitor of phosphodiesterase III and is used clinically in patients with heart failure and those undergoing cardiac surgery; however, little is known about the effects of OLP on hepatoprotection. The purpose of this study aimed to determine whether OLP has protective effects in in vivo and in vitro rat models of endotoxin-induced liver injury after hepatectomy and to clarify the mechanisms of action of OLP. In the in vivo model, rats underwent 70% partial hepatectomy and lipopolysaccharide treatment (PH/LPS). OLP administration increased survival by 85.7% and decreased tumor necrosis factor-α, C-X-C motif chemokine ligand 1, and inducible nitric oxide synthase (iNOS) mRNA expression in the livers of rats treated with PH/LPS. OLP also suppressed nuclear translocation and/or DNA binding ability of nuclear factor kappa B (NF-κB). Pathological liver damage induced by PH/LPS was alleviated and neutrophil infiltration was reduced by OLP. Primary cultured rat hepatocytes treated with the pro-inflammatory cytokine interleukin-1ß (IL-1ß) were used as a model of in vitro liver injury. Co-treatment with OLP inhibited dose-dependently IL-1ß-stimulated iNOS induction and NF-κB activation. Our results demonstrate that OLP may partially inhibit the induction of several inflammatory mediators through the suppression of NF-κB and thus prevent liver injury induced by endotoxin after liver resection.


Subject(s)
Disease Models, Animal , Hepatectomy , Hepatocytes , Imidazoles , NF-kappa B , Nitric Oxide Synthase Type II , Pyridones , Animals , Hepatectomy/adverse effects , Hepatocytes/drug effects , Hepatocytes/metabolism , Rats , Male , Pyridones/pharmacology , Pyridones/therapeutic use , NF-kappa B/metabolism , Imidazoles/pharmacology , Nitric Oxide Synthase Type II/metabolism , Phosphodiesterase 3 Inhibitors/pharmacology , Phosphodiesterase 3 Inhibitors/therapeutic use , Interleukin-1beta/metabolism , Lipopolysaccharides/adverse effects , Lipopolysaccharides/toxicity , Sepsis/drug therapy , Rats, Sprague-Dawley , Cells, Cultured , Tumor Necrosis Factor-alpha/metabolism , Chemokine CXCL1/metabolism , Liver/drug effects , Liver/pathology , Liver/metabolism
5.
J Cell Mol Med ; 28(13): e18386, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38990057

ABSTRACT

Acute lung injury (ALI) is a major pathophysiological problem characterized by severe inflammation, resulting in high morbidity and mortality. Plumbagin (PL), a major bioactive constituent extracted from the traditional Chinese herb Plumbago zeylanica, has been shown to possess anti-inflammatory and antioxidant pharmacological activities. However, its protective effect on ALI has not been extensively studied. The objective of this study was to investigate the protective effect of PL against ALI induced by LPS and to elucidate its possible mechanisms both in vivo and in vitro. PL treatment significantly inhibited pathological injury, MPO activity, and the wet/dry ratio in lung tissues, and decreased the levels of inflammatory cells and inflammatory cytokines TNF-α, IL-1ß, IL-6 in BALF induced by LPS. In addition, PL inhibited the activation of the PI3K/AKT/mTOR signalling pathway, increased the activity of antioxidant enzymes CAT, SOD, GSH and activated the Keap1/Nrf2/HO-1 signalling pathway during ALI induced by LPS. To further assess the association between the inhibitory effects of PL on ALI and the PI3K/AKT/mTOR and Keap1/Nrf2/HO-1 signalling, we pretreated RAW264.7 cells with 740Y-P and ML385. The results showed that the activation of PI3K/AKT/mTOR signalling reversed the protective effect of PL on inflammatory response induced by LPS. Moreover, the inhibitory effects of PL on the production of inflammatory cytokines induced by LPS also inhibited by downregulating Keap1/Nrf2/HO-1 signalling. In conclusion, the results indicate that the PL ameliorate LPS-induced ALI by regulating the PI3K/AKT/mTOR and Keap1-Nrf2/HO-1 signalling, which may provide a novel therapeutic perspective for PL in inhibiting ALI.


Subject(s)
Acute Lung Injury , Kelch-Like ECH-Associated Protein 1 , Lipopolysaccharides , NF-E2-Related Factor 2 , Naphthoquinones , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Signal Transduction , TOR Serine-Threonine Kinases , Animals , Acute Lung Injury/metabolism , Acute Lung Injury/drug therapy , Acute Lung Injury/chemically induced , Acute Lung Injury/pathology , NF-E2-Related Factor 2/metabolism , TOR Serine-Threonine Kinases/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Lipopolysaccharides/adverse effects , Lipopolysaccharides/toxicity , Naphthoquinones/pharmacology , Signal Transduction/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Mice , Male , Cytokines/metabolism , Heme Oxygenase-1/metabolism , RAW 264.7 Cells , Anti-Inflammatory Agents/pharmacology , Heme Oxygenase (Decyclizing)/metabolism , Membrane Proteins/metabolism
6.
J Physiol Pharmacol ; 75(3)2024 Jun.
Article in English | MEDLINE | ID: mdl-39042387

ABSTRACT

Myocarditis (MC) is a myocardial inflammatory disease that threats human life. Pitavastatin (Pit) is a unique lipophilic statin with potent effects on lowering plasma total cholesterol and triacylglycerols. It has been reported to have pleiotropic effects, such as reducing inflammation and oxidative stress. However, the regulatory mechanism of Pit in MC remains a mystery. Two MC models were established in vitro (lipopolysaccharides-(LPS)-stimulated H9c2 cells) and in vivo (intraperitoneal injection of LPS in mice). The levels of microRNA-106b-5p (miR-106b-5p) and mitogen-activated protein kinase kinase kinase 2 (MAP3K2) were detected. ELISA was used to analyze in vivo cell inflammatory factors and myocardial injury markers, kits were used to detect the expression of antioxidant enzymes, cell counting kit-8 (CCK-8) was used to detect cell proliferation, and flow cytometry was used to detect apoptosis. Hematoxylin and eosin (HE) staining was used to detect the pathological changes of myocardial tissue in mice, and TUNEL staining was used to detect in vivo tissue cell apoptosis. The regulatory mechanism of Pit on miR-106b-5p/MAP3K2 was verified by a series of functional rescue experiments. The results demonstrated that in LPS-induced H9c2 cells, antioxidant enzymes decreased and pro-inflammatory factors and cardiac injury markers increased (p<0.05). However, these phenomenons were attenuated by Pit pretreatment. LPS decreased miR-106b-5p and elevated MAP3K2 in H9c2 cells, while Pit could recover their expression patterns (p<0.05). MAP3K2 was confirmed as a target gene of miR-106b-5p. Upregulating miR-106b-5p or downregulating MAP3K2 could further promote the protective effect of Pit, and vice versa (p<0.05). In addition, in the LPS-induced MC mouse model, histological examination showed that Pit significantly improved the myocardial tissue damage in MC mice, while downregulating miR-106b-5p or upregulating MAP3K2 could suppress the ameliorative effect of Pit (p<0.05). In conclusion, our study demonstrated that Pit ameliorates myocardial injury by suppressing myocardial inflammation and oxidative stress by modulating the miR-106b-5p/MAP3K2 axis.


Subject(s)
Lipopolysaccharides , MicroRNAs , Myocarditis , Oxidative Stress , Animals , MicroRNAs/metabolism , MicroRNAs/genetics , Oxidative Stress/drug effects , Myocarditis/drug therapy , Myocarditis/metabolism , Myocarditis/pathology , Male , Mice , Cell Line , Lipopolysaccharides/toxicity , Quinolines/pharmacology , MAP Kinase Kinase Kinase 2/metabolism , Rats , Apoptosis/drug effects , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Myocardium/pathology , Myocardium/metabolism , Mice, Inbred BALB C , Inflammation/metabolism , Inflammation/drug therapy , Inflammation/pathology , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology
7.
J Neuroinflammation ; 21(1): 174, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39014482

ABSTRACT

BACKGROUND: Specific microglia responses are thought to contribute to the development and progression of neurodegenerative diseases, including Parkinson's disease (PD). However, the phenotypic acquisition of microglial cells and their role during the underlying neuroinflammatory processes remain largely elusive. Here, according to the multiple-hit hypothesis, which stipulates that PD etiology is determined by a combination of genetics and various environmental risk factors, we investigate microglial transcriptional programs and morphological adaptations under PARK7/DJ-1 deficiency, a genetic cause of PD, during lipopolysaccharide (LPS)-induced inflammation. METHODS: Using a combination of single-cell RNA-sequencing, bulk RNA-sequencing, multicolor flow cytometry and immunofluorescence analyses, we comprehensively compared microglial cell phenotypic characteristics in PARK7/DJ-1 knock-out (KO) with wildtype littermate mice following 6- or 24-h intraperitoneal injection with LPS. For translational perspectives, we conducted corresponding analyses in human PARK7/DJ-1 mutant induced pluripotent stem cell (iPSC)-derived microglia and murine bone marrow-derived macrophages (BMDMs). RESULTS: By excluding the contribution of other immune brain resident and peripheral cells, we show that microglia acutely isolated from PARK7/DJ-1 KO mice display a distinct phenotype, specially related to type II interferon and DNA damage response signaling, when compared with wildtype microglia, in response to LPS. We also detected discrete signatures in human PARK7/DJ-1 mutant iPSC-derived microglia and BMDMs from PARK7/DJ-1 KO mice. These specific transcriptional signatures were reflected at the morphological level, with microglia in LPS-treated PARK7/DJ-1 KO mice showing a less amoeboid cell shape compared to wildtype mice, both at 6 and 24 h after acute inflammation, as also observed in BMDMs. CONCLUSIONS: Taken together, our results show that, under inflammatory conditions, PARK7/DJ-1 deficiency skews microglia towards a distinct phenotype characterized by downregulation of genes involved in type II interferon signaling and a less prominent amoeboid morphology compared to wildtype microglia. These findings suggest that the underlying oxidative stress associated with the lack of PARK7/DJ-1 affects microglia neuroinflammatory responses, which may play a causative role in PD onset and progression.


Subject(s)
Inflammation , Lipopolysaccharides , Mice, Knockout , Microglia , Protein Deglycase DJ-1 , Animals , Protein Deglycase DJ-1/deficiency , Protein Deglycase DJ-1/genetics , Protein Deglycase DJ-1/metabolism , Microglia/metabolism , Microglia/pathology , Microglia/drug effects , Mice , Lipopolysaccharides/toxicity , Lipopolysaccharides/pharmacology , Inflammation/pathology , Inflammation/chemically induced , Inflammation/metabolism , Inflammation/genetics , Humans , Mice, Inbred C57BL , Neuroinflammatory Diseases/pathology , Neuroinflammatory Diseases/metabolism , Neuroinflammatory Diseases/chemically induced , Neuroinflammatory Diseases/genetics
8.
J Neuroinflammation ; 21(1): 169, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961424

ABSTRACT

BACKGROUND: Understanding the mechanism behind sepsis-associated encephalopathy (SAE) remains a formidable task. This study endeavors to shed light on the complex cellular and molecular alterations that occur in the brains of a mouse model with SAE, ultimately unraveling the underlying mechanisms of this condition. METHODS: We established a murine model using intraperitoneal injection of lipopolysaccharide (LPS) in wild type and Anxa1-/- mice and collected brain tissues for analysis at 0-hour, 12-hour, 24-hour, and 72-hour post-injection. Utilizing advanced techniques such as single-nucleus RNA sequencing (snRNA-seq) and Stereo-seq, we conducted a comprehensive characterization of the cellular responses and molecular patterns within the brain. RESULTS: Our study uncovered notable temporal differences in the response to LPS challenge between Anxa1-/- (annexin A1 knockout) and wild type mice, specifically at the 12-hour and 24-hour time points following injection. We observed a significant increase in the proportion of Astro-2 and Micro-2 cells in these mice. These cells exhibited a colocalization pattern with the vascular subtype Vas-1, forming a distinct region known as V1A2M2, where Astro-2 and Micro-2 cells surrounded Vas-1. Moreover, through further analysis, we discovered significant upregulation of ligands and receptors such as Timp1-Cd63, Timp1-Itgb1, Timp1-Lrp1, as well as Ccl2-Ackr1 and Cxcl2-Ackr1 within this region. In addition, we observed a notable increase in the expression of Cd14-Itgb1, Cd14-Tlr2, and Cd14-C3ar1 in regions enriched with Micro-2 cells. Additionally, Cxcl10-Sdc4 showed broad upregulation in brain regions containing both Micro-2 and Astro-2 cells. Notably, upon LPS challenge, there was an observed increase in Anxa1 expression in the mouse brain. Furthermore, our study revealed a noteworthy increase in mortality rates following Anxa1 knockdown. However, we did not observe substantial differences in the types, numbers, or distribution of other brain cells between Anxa1-/- and wildtype mice over time. Nevertheless, when comparing the 24-hour post LPS injection time point, we observed a significant decrease in the proportion and distribution of Micro-2 and Astro-2 cells in the vicinity of blood vessels in Anxa1-/- mice. Additionally, we noted reduced expression levels of several ligand-receptor pairs including Cd14-Tlr2, Cd14-C3ar1, Cd14-Itgb1, Cxcl10-Sdc4, Ccl2-Ackr1, and Cxcl2-Ackr1. CONCLUSIONS: By combining snRNA-seq and Stereo-seq techniques, our study successfully identified a distinctive cellular colocalization, referred to as a special pathological niche, comprising Astro-2, Micro-2, and Vas-1 cells. Furthermore, we observed an upregulation of ligand-receptor pairs within this niche. These findings suggest a potential association between this cellular arrangement and the underlying mechanisms contributing to SAE or the increased mortality observed in Anxa1 knockdown mice.


Subject(s)
Astrocytes , Brain , Disease Models, Animal , Lipopolysaccharides , Mice, Knockout , Microglia , Sepsis-Associated Encephalopathy , Animals , Mice , Lipopolysaccharides/toxicity , Sepsis-Associated Encephalopathy/pathology , Sepsis-Associated Encephalopathy/genetics , Sepsis-Associated Encephalopathy/metabolism , Microglia/metabolism , Microglia/pathology , Brain/pathology , Brain/metabolism , Astrocytes/metabolism , Astrocytes/pathology , Sequence Analysis, RNA/methods , Mice, Inbred C57BL , Transcriptome , Male
9.
Respir Res ; 25(1): 263, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956592

ABSTRACT

BACKGROUND: Aberrant activation of macrophages is associated with pathogenesis of acute lung injury (ALI). However, the potential pathogenesis has not been explored. OBJECTIVES: We aimed to identify whether histone deacetylase (HDAC) 10 is involved in lipopolysaccharide (LPS)-exposed ALI and reveal the underlying pathogenesis by which it promotes lung inflammation in LPS-exposed ALI via modifying P62 with deacetylation. METHODS: We constructed an ALI mice model stimulated with LPS to determine the positive effect of Hdac10 deficiency. Moreover, we cultured murine alveolar macrophage cell line (MH-S cells) and primary bone marrow-derived macrophages (BMDMs) to explore the pro-inflammatory activity and mechanism of HDAC10 after LPS challenge. RESULTS: HDAC10 expression was increased both in mice lung tissues and macrophage cell lines and promoted inflammatory cytokines production exposed to LPS. Hdac10 deficiency inhibited autophagy and inflammatory response after LPS stimulation. In vivo, Hdac10fl/fl-LysMCre mice considerably attenuated lung inflammation and inflammatory cytokines release exposed to LPS. Mechanistically, HDAC10 interacts with P62 and mediates P62 deacetylation at lysine 165 (K165), by which it promotes P62 expression and increases inflammatory cytokines production. Importantly, we identified that Salvianolic acid B (SAB), an HDAC10 inhibitor, reduces lung inflammatory response in LPS-stimulated ALI. CONCLUSION: These results uncover a previously unknown role for HDAC10 in regulating P62 deacetylation and aggravating lung inflammation in LPS-induced ALI, implicating that targeting HDAC10 is an effective therapy for LPS-exposed ALI.


Subject(s)
Acute Lung Injury , Histone Deacetylases , Lipopolysaccharides , Lysine , Mice, Inbred C57BL , Animals , Acute Lung Injury/chemically induced , Acute Lung Injury/prevention & control , Acute Lung Injury/metabolism , Acute Lung Injury/genetics , Acute Lung Injury/pathology , Lipopolysaccharides/toxicity , Mice , Acetylation , Histone Deacetylases/metabolism , Histone Deacetylases/genetics , Histone Deacetylases/deficiency , Lysine/metabolism , Mice, Knockout , Male , Sequestosome-1 Protein/metabolism , Sequestosome-1 Protein/genetics , Myeloid Cells/metabolism
10.
Sci Rep ; 14(1): 16270, 2024 07 15.
Article in English | MEDLINE | ID: mdl-39009650

ABSTRACT

Steroid-induced osteonecrosis of the femoral head (SONFH) is the predominant cause of non-traumatic osteonecrosis of the femoral head (ONFH). Impaired blood supply and reduced osteogenic activity of the femoral head are the key pathogenic mechanisms of SONFH. Fibroblast growth factor 23 (FGF23) levels are not only a biomarker for early vascular lesions caused by abnormal mineral metabolism, but can also act directly on the peripheral vascular system, leading to vascular pathology. The aim of this study was to observe the role of FGF23 on bone microarchitecture and vascular endothelium, and to investigate activation of pyroptosis in SONFH. Lipopolysaccharide (LPS) combined with methylprednisolone (MPS) was applied for SONFH mouse models, and adenovirus was used to increase or decrease the level of FGF23. Micro-CT and histopathological staining were used to observe the structure of the femoral head, and immunohistochemical staining was used to observe the vascular density. The cells were further cultured in vitro and placed in a hypoxic environment for 12 h to simulate the microenvironment of vascular injury during SONFH. The effect of FGF23 on osteogenic differentiation was evaluated using alkaline phosphatase staining, alizarin red S staining and expression of bone formation-related proteins. Matrigel tube formation assay in vitro and immunofluorescence were used to detect the ability of FGF23 to affect endothelial cell angiogenesis. Steroids activated the pyroptosis signaling pathway, promoted the secretion of inflammatory factors in SONFH models, led to vascular endothelial dysfunction and damaged the femoral head structure. In addition, FGF23 inhibited the HUVECs angiogenesis and BMSCs osteogenic differentiation. FGF23 silencing attenuated steroid-induced osteonecrosis of the femoral head by inhibiting the pyroptosis signaling pathway, and promoting osteogenic differentiation of BMSCs and angiogenesis of HUVECs in vitro.


Subject(s)
Femur Head Necrosis , Fibroblast Growth Factor-23 , Fibroblast Growth Factors , Osteogenesis , Pyroptosis , Pyroptosis/drug effects , Fibroblast Growth Factor-23/metabolism , Animals , Femur Head Necrosis/chemically induced , Femur Head Necrosis/metabolism , Femur Head Necrosis/pathology , Mice , Fibroblast Growth Factors/metabolism , Osteogenesis/drug effects , Humans , Femur Head/pathology , Femur Head/metabolism , Disease Models, Animal , Methylprednisolone/pharmacology , Male , Lipopolysaccharides/toxicity , Human Umbilical Vein Endothelial Cells/metabolism , Cell Differentiation , Steroids/pharmacology
11.
Biomed Pharmacother ; 177: 117163, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39018876

ABSTRACT

Graveoline exhibits various biological activities. However, only limited studies have focused on its hepatoprotective properties. This study evaluated the anti-inflammatory and hepatoprotective activities of graveoline, a minor 2-phenylquinolin-4-one alkaloid isolated from Ruta graveolens L., in a liver injury model in vitro and in vivo. A network pharmacology approach was used to investigate the potential signaling pathway associated with the hepatoprotective activity of graveoline. Subsequently, biological experiments were conducted to validate the findings. Topological analysis of the KEGG pathway enrichment revealed that graveoline mediates its hepatoprotective activity through genes associated with the hepatitis B viral infection pathway. Biological experiments demonstrated that graveoline effectively reduced the levels of alanine transaminase and aspartate transaminase in lipopolysaccharide (LPS)-induced HepG2 cells. Graveoline exerted antihepatitic activity by inhibiting the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) and elevated the anti-inflammatory cytokines interleukin-4 (IL-4) and interleukin-10 (IL-10) in vitro and in vivo. Additionally, graveoline exerted its hepatoprotective activity by inhibiting JAK1 and STAT3 phosphorylation both in vitro and in vivo. In summary, graveoline can attenuate acute liver injury by inhibiting the TNF-α inflammasome, activating IL-4 and IL-10, and suppressing the JAK1/STAT3 signaling pathway. This study sheds light on the potential of graveoline as a promising therapeutic agent for treating liver injury.


Subject(s)
Chemical and Drug Induced Liver Injury , Galactosamine , Janus Kinase 1 , Lipopolysaccharides , STAT3 Transcription Factor , Signal Transduction , STAT3 Transcription Factor/metabolism , Janus Kinase 1/metabolism , Janus Kinase 1/antagonists & inhibitors , Animals , Humans , Lipopolysaccharides/toxicity , Signal Transduction/drug effects , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/prevention & control , Chemical and Drug Induced Liver Injury/drug therapy , Male , Hep G2 Cells , Galactosamine/toxicity , Mice , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/isolation & purification , Cytokines/metabolism , Quinolines/pharmacology
12.
J Neuroimmune Pharmacol ; 19(1): 38, 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-39066908

ABSTRACT

Repetitive exposure of innate immune cells to a subthreshold dosage of endotoxin components may modulate inflammatory responses. However, the regulatory mechanisms in the interactions between the central nervous system (CNS) and the immune system remain unclear. This study aimed to investigate the effects of lipopolysaccharide (LPS) preconditioning in repeated social defeat stress (RSDS)-induced abnormal immune responses and behavioral impairments. This study aimed to elucidate the mechanisms that underlie the protective effects of repeated administration of a subthreshold dose LPS on behavioral impairments using the RSDS paradigm. LPS preconditioning improved abnormal behaviors in RSDS-defeated mice, accompanied by decreased monoamine oxidases and increased glucocorticoid receptor expression in the hippocampus. In addition, pre-treated with LPS significantly decreased the recruited peripheral myeloid cells (CD11b+CD45hi), mainly circulating inflammatory monocytes (CD11b+CD45hiLy6ChiCCR2+) into the brain in response to RSDS challenge. Importantly, we found that LPS preconditioning exerts its protective properties by regulating lipocalin-2 (LCN2) expression in microglia, which subsequently induces expressions of chemokine CCL2 and pro-inflammatory cytokine. Subsequently, LPS-preconditioning lessened the resident microglia population (CD11b+CD45intCCL2+) in the brains of the RSDS-defeated mice. Moreover, RSDS-associated expressions of leukocytes (CD11b+CD45+CCR2+) and neutrophils (CD11b+CD45+Ly6G+) in the bone marrow, spleen, and blood were also attenuated by LPS-preconditioning. In particular, LPS preconditioning also promoted the expression of endogenous antioxidants and anti-inflammatory proteins in the hippocampus. Our results demonstrate that LPS preconditioning ameliorates lipocalin 2-associated microglial activation and aberrant immune response and promotes the expression of endogenous antioxidants and anti-inflammatory protein, thereby maintaining the homeostasis of pro-inflammation/anti-inflammation in both the brain and immune system, ultimately protecting the mice from RSDS-induced aberrant immune response and behavioral changes.


Subject(s)
Lipopolysaccharides , Mice, Inbred C57BL , Social Defeat , Stress, Psychological , Animals , Lipopolysaccharides/toxicity , Mice , Male , Stress, Psychological/immunology , Microglia/drug effects , Microglia/metabolism , Microglia/immunology , Behavior, Animal/drug effects , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/immunology , Lipocalin-2/metabolism
13.
Respir Res ; 25(1): 291, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39080660

ABSTRACT

Acute lung injury (ALI) is characterized by an unregulated inflammatory reaction, often leading to severe morbidity and ultimately death. Excessive inflammation caused by M1 macrophage polarization and pyroptosis has been revealed to have a critical role in ALI. Recent study suggests that glycolytic reprogramming is important in the regulation of macrophage polarization and pyroptosis. However, the particular processes underlying ALI have yet to be identified. In this study, we established a Lipopolysaccharide(LPS)-induced ALI model and demonstrated that blocking glycolysis by using 2-Deoxy-D-glucose(2-DG) significantly downregulated the expression of M1 macrophage markers and pyroptosis-related genes, which was consistent with the in vitro results. Furthermore, our research has revealed that Phosphoglycerate Kinase 1(PGK1), an essential enzyme in the glycolysis pathway, interacts with NOD-, LRR- and pyrin domain-containing protein 3(NLRP3). We discovered that LPS stimulation improves the combination of PGK1 and NLRP3 both in vivo and in vitro. Interestingly, the absence of PGK1 reduces the phosphorylation level of NLRP3. Based on in vitro studies with mice bone marrow-derived macrophages (BMDMs), we further confirmed that siPGK1 plays a protective role by inhibiting macrophage pyroptosis and M1 macrophage polarization. The PGK1 inhibitor NG52 suppresses the occurrence of excessive inflammation in ALI. In general, it is plausible to consider a therapeutic strategy that focuses on modulating the relationship between PGK1 and NLRP3 as a means to mitigate the activation of inflammatory macrophages in ALI.


Subject(s)
Acute Lung Injury , Macrophages , Mice, Inbred C57BL , NLR Family, Pyrin Domain-Containing 3 Protein , Phosphoglycerate Kinase , Pyroptosis , Pyroptosis/physiology , Pyroptosis/drug effects , Animals , Phosphoglycerate Kinase/metabolism , Phosphoglycerate Kinase/genetics , Acute Lung Injury/pathology , Acute Lung Injury/metabolism , Acute Lung Injury/chemically induced , Acute Lung Injury/enzymology , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Mice , Macrophages/metabolism , Macrophages/drug effects , Macrophages/enzymology , Glycolysis/physiology , Glycolysis/drug effects , Male , Lipopolysaccharides/toxicity , Mice, Knockout , Cells, Cultured
14.
CNS Neurosci Ther ; 30(7): e14887, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39073013

ABSTRACT

AIMS: Neuroinflammation is a recognized contributor to cognitive disorders like Alzheimer's disease, with ferroptosis emerging as a novel mechanism underlying cognitive dysfunction associated with neuroinflammation. Insulin, pivotal in the central nervous system, holds promise for cognitive function enhancement. This study aimed to establish a cognitive impairment model through intracerebroventricular injection of lipopolysaccharide (LPS) and explore the impact of intracerebroventricular insulin injection on cognitive function in mice. METHODS: We employed diverse experimental techniques, including animal behavior testing, molecular assays, targeted metabolomics, nuclear medicine, and electron microscopy, to assess neurodegenerative changes, brain insulin resistance (IR), glucose uptake and metabolism, and ferroptosis. The model of cognitive impairment was induced via intracerebroventricular injection of LPS, followed by intracerebroventricular administration of insulin to evaluate its effects. RESULTS: Insulin treatment effectively mitigated LPS-induced cognitive decline and safeguarded against neuronal degeneration. Furthermore, insulin alleviated LPS-induced insulin resistance, enhanced glucose uptake in the hippocampus, and promoted the Pentose Phosphate Pathway (PPP) and nicotinamide adenine dinucleotide phosphate (NADPH) production. Additionally, insulin activated the glutathione (GSH)-glutathione peroxidase 4 (GPX4) pathway, reducing lipid peroxidation, and mitochondrial damage characteristic of LPS-induced ferroptosis in the hippocampus. CONCLUSION: Our findings underscore the therapeutic potential of insulin in alleviating LPS-induced cognitive impairment and ferroptosis by modulating glucose metabolism. This study offers a promising avenue for future interventions targeting cognitive decline.


Subject(s)
Cognitive Dysfunction , Ferroptosis , Glucose , Hippocampus , Insulin , Lipopolysaccharides , Animals , Ferroptosis/drug effects , Ferroptosis/physiology , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/chemically induced , Cognitive Dysfunction/metabolism , Lipopolysaccharides/toxicity , Hippocampus/drug effects , Hippocampus/metabolism , Mice , Male , Glucose/metabolism , Mice, Inbred C57BL , Insulin Resistance/physiology
15.
Clin Exp Pharmacol Physiol ; 51(9): e13910, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39073215

ABSTRACT

Myocardial injury and cardiovascular dysfunction are the most common complications of sepsis, and effective therapeutic candidate is still lacking. This study aims to investigate the protective effect of oxycodone in myocardial injury of lipopolysaccharide-induced sepsis and its related signalling pathways. Wild-type and nuclear factor erythroid 2-related factor 2 (Nrf2)-knockout mice, as well as H9c2 cardiomyocytes cultures treated with lipopolysaccharide (LPS) were used as models of septic myocardial injury. H9c2 cardiomyocytes culture showed that oxycodone protected cells from pyroptosis induced by LPS. Mice model confirmed that oxycodone pretreatment significantly attenuated myocardial pathological damage and improved cardiac function demonstrated by increased ejection fraction (EF) and fractional shortening (FS), as well as decreased cardiac troponin I (cTnI) and creatine kinase isoenzymes MB (CK-MB). Oxycodone also reduced the levels of inflammatory factors and oxidative stress damage induced by LPS, which involves pyroptosis-related proteins including: Nod-like receptor protein 3 (NLRP3), Caspase 1, Apoptosis-associated speck-like protein contain a CARD (ASC), and Gasdermin D (GSDMD). These changes were mediated by Nrf2 and heme oxygenase-1 (HO-1) because Nrf2-knockout mice or Nrf2 knockdown in H9c2 cells significantly reversed the beneficial effect of oxycodone on oxidative stress, inflammatory responses and NLRP3-mediated pyroptosis. Our findings yielded that oxycodone therapy reduces LPS-induced myocardial injury by suppressing NLRP3-mediated pyroptosis via the Nrf2/HO-1 signalling pathway in vivo and in vitro.


Subject(s)
Heme Oxygenase-1 , Inflammation , Lipopolysaccharides , Myocytes, Cardiac , NF-E2-Related Factor 2 , Oxycodone , Pyroptosis , Signal Transduction , Animals , NF-E2-Related Factor 2/metabolism , Pyroptosis/drug effects , Lipopolysaccharides/toxicity , Signal Transduction/drug effects , Mice , Inflammation/metabolism , Inflammation/drug therapy , Inflammation/pathology , Heme Oxygenase-1/metabolism , Oxycodone/pharmacology , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Male , Cell Line , Rats , Oxidation-Reduction/drug effects , Mice, Knockout , Mice, Inbred C57BL , Oxidative Stress/drug effects
16.
Cell Biol Toxicol ; 40(1): 60, 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39073694

ABSTRACT

Triptolide (TP) is a major active and toxic composition of the Chinese medicine Tripterygium wilfordii Hook. F. (TWHF), exhibiting various therapeutic bioactivities. Among the toxic effects, the hepatotoxicity of TP deserves serious attention. Previously, our research group proposed a new view of TP-related hepatotoxicity: hepatic hypersensitivity under lipopolysaccharide (LPS) stimulation. However, the mechanism of TP/LPS-induced hepatic hypersensitivity remains unclear. In this study, we investigated the mechanism underlying TP/LPS-induced hypersensitivity from the perspective of the inhibition of proteasome activity, activated endoplasmic reticulum stress (ERS)-related apoptosis, and the accumulation of reactive oxygen species (ROS). Our results showed that N-acetylcysteine (NAC), a common ROS inhibitor, decreased the expression of cleaved caspase-3 and cleaved PARP, which are associated with FLIP enhancement. Moreover, 4-phenylbutyric acid (4-PBA), an ERS inhibitor, was able to alleviate TP/LPS-induced hepatotoxicity by reducing ERS-related apoptosis protein expression (GRP78, p-eIF2α/eIF2α, ATF4, CHOP, cleaved caspase-3 and cleaved PARP) and ROS levels, with ATF4 being an indispensable mediator. In addition, the proteasome activity inhibitor MG-132 further aggravated ERS-related apoptosis, which indicated that the inhibition of proteasome activity also plays an important role in TP/LPS-related liver injuries. In summary, we propose that TP/LPS may upregulate the activation of ERS-associated apoptosis by inhibiting proteasome activity and enhancing ROS production through ATF4.


Subject(s)
Acetylcysteine , Apoptosis , Diterpenes , Endoplasmic Reticulum Chaperone BiP , Endoplasmic Reticulum Stress , Epoxy Compounds , Lipopolysaccharides , Phenanthrenes , Proteasome Endopeptidase Complex , Proteasome Inhibitors , Reactive Oxygen Species , Phenanthrenes/pharmacology , Phenanthrenes/toxicity , Diterpenes/pharmacology , Diterpenes/toxicity , Endoplasmic Reticulum Stress/drug effects , Apoptosis/drug effects , Lipopolysaccharides/toxicity , Epoxy Compounds/toxicity , Epoxy Compounds/pharmacology , Animals , Reactive Oxygen Species/metabolism , Proteasome Endopeptidase Complex/metabolism , Proteasome Inhibitors/pharmacology , Acetylcysteine/pharmacology , Activating Transcription Factor 4/metabolism , Phenylbutyrates/pharmacology , Mice , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Liver/drug effects , Liver/pathology , Liver/metabolism , Caspase 3/metabolism , Male , Leupeptins
17.
J Neuroinflammation ; 21(1): 143, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38822367

ABSTRACT

The dysregulation of pro- and anti-inflammatory processes in the brain has been linked to the pathogenesis of major depressive disorder (MDD), although the precise mechanisms remain unclear. In this study, we discovered that microglial conditional knockout of Pdcd4 conferred protection against LPS-induced hyperactivation of microglia and depressive-like behavior in mice. Mechanically, microglial Pdcd4 plays a role in promoting neuroinflammatory responses triggered by LPS by inhibiting Daxx-mediated PPARγ nucleus translocation, leading to the suppression of anti-inflammatory cytokine IL-10 expression. Finally, the antidepressant effect of microglial Pdcd4 knockout under LPS-challenged conditions was abolished by intracerebroventricular injection of the IL-10 neutralizing antibody IL-10Rα. Our study elucidates the distinct involvement of microglial Pdcd4 in neuroinflammation, suggesting its potential as a therapeutic target for neuroinflammation-related depression.


Subject(s)
Co-Repressor Proteins , Interleukin-10 , Mice, Knockout , Microglia , Neuroinflammatory Diseases , PPAR gamma , Signal Transduction , Animals , Male , Mice , Adaptor Proteins, Signal Transducing/deficiency , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Apoptosis Regulatory Proteins/metabolism , Apoptosis Regulatory Proteins/genetics , Apoptosis Regulatory Proteins/deficiency , Co-Repressor Proteins/genetics , Co-Repressor Proteins/metabolism , Depression/metabolism , Depression/etiology , Interleukin-10/metabolism , Interleukin-10/deficiency , Interleukin-10/genetics , Lipopolysaccharides/toxicity , Mice, Inbred C57BL , Microglia/metabolism , Microglia/drug effects , Molecular Chaperones/genetics , Molecular Chaperones/metabolism , Neuroinflammatory Diseases/metabolism , PPAR gamma/metabolism , PPAR gamma/genetics , Signal Transduction/physiology , Signal Transduction/drug effects
18.
Eur J Med Res ; 29(1): 349, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38937814

ABSTRACT

BACKGROUND: Sepsis is one of the most common clinical diseases, which is characterized by a serious and uncontrollable inflammatory response. LPS-induced inflammation is a critical pathological event in sepsis, but the underlying mechanism has not yet been fully elucidated. METHODS: The animal model was established for two batches. In the first batch of experiments, Adult C57BL/6J mice were randomly divided into control group and LPS (5 mg/kg, i.p.)group . In the second batch of experiments, mice were randomly divided into control group, LPS group, and LPS+VX765(10 mg/kg, i.p., an inhibitor of NLRP3 inflammasome) group. After 24 hours, mice were anesthetized with isoflurane, blood and intestinal tissue were collected for tissue immunohistochemistry, Western blot analysis and ELISA assays. RESULTS: The C57BL/6J mice injected with LPS for twenty-four hours could exhibit severe inflammatory reaction including an increased IL-1ß, IL-18 in serum and activation of NLRP3 inflammasome in intestine. The injection of VX765 could reverse these effects induced by LPS. These results indicated that the increased level of IL-1ß and IL-18 in serum induced by LPS is related to the increased intestinal permeability and activation of NLRP3 inflammasome. In the second batch of experiments, results of western blot and immunohistochemistry showed that Slit2 and Robo4 were significant decreased in intestine of LPS group, while the expression of VEGF was significant increased. Meanwhile, the protein level of tight junction protein ZO-1, occludin, and claudin-5 were significantly lower than in control group, which could also be reversed by VX765 injection. CONCLUSIONS: In this study, we revealed that Slit2-Robo4 signaling pathway and tight junction in intestine may be involved in LPS-induced inflammation in mice, which may account for the molecular mechanism of sepsis.


Subject(s)
Inflammation , Intercellular Signaling Peptides and Proteins , Lipopolysaccharides , Mice, Inbred C57BL , Nerve Tissue Proteins , Signal Transduction , Tight Junctions , Animals , Lipopolysaccharides/toxicity , Mice , Signal Transduction/drug effects , Nerve Tissue Proteins/metabolism , Inflammation/metabolism , Inflammation/chemically induced , Intercellular Signaling Peptides and Proteins/metabolism , Tight Junctions/metabolism , Tight Junctions/drug effects , Male , Receptors, Cell Surface/metabolism , Receptors, Immunologic/metabolism , Intestinal Mucosa/metabolism , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Intestines/drug effects , Intestines/pathology , Disease Models, Animal , Inflammasomes/metabolism
19.
Toxicology ; 506: 153859, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38825031

ABSTRACT

The toxicity of heated tobacco products (HTP) on the immune cells remains unclear. Here, U937-differentiated macrophages were exposed to a single and short-term exposure (30 minutes) of HTP vapor or cigarette smoke (CS) in an air-liquid interface (ALI) system to evaluate the effects on macrophages' early activation and polarization. In our system, HTP released lower amounts of polycyclic aromatic hydrocarbons (PAHs), but higher nicotine levels than CS into the cell culture supernatant. Both tobacco products triggered the expression of the α-7 nicotinic receptor (α7 nAChR) and reactive oxygen species (ROS) production. When challenged with a bacterial product, lipopolysaccharide (LPS), cells exposed to HTP or CS failed to respond properly and enhance ROS production upon LPS stimuli. Furthermore, both tobacco products also impaired bacterial phagocytosis and the exposures triggered higher IL-1ß secretion. The α7 nAChR antagonist treatment rescued the effects caused only by HTP exposure. The CS-exposed group switched macrophage to the pro-inflammatory M1, while HTP polarized to the suppressive M2 profile. Associated, data highlight that HTP and CS exposures similarly activate macrophages; nonetheless, the α7 nAChR pathway is only involved in HTP actions, and the distinct subsequent polarization caused by HTP or CS may influence the outcome of host defense.


Subject(s)
Macrophage Activation , Macrophages , Nicotiana , Reactive Oxygen Species , Smoke , alpha7 Nicotinic Acetylcholine Receptor , Macrophage Activation/drug effects , Humans , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , alpha7 Nicotinic Acetylcholine Receptor/metabolism , Smoke/adverse effects , Reactive Oxygen Species/metabolism , U937 Cells , Tobacco Products , Phagocytosis/drug effects , Nicotine/toxicity , Hot Temperature , Lipopolysaccharides/toxicity , Polycyclic Aromatic Hydrocarbons/toxicity , Interleukin-1beta/metabolism
20.
Am J Physiol Heart Circ Physiol ; 327(2): H390-H398, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38874615

ABSTRACT

The endothelial glycocalyx (EG), covering the luminal side of endothelial cells, regulates vascular permeability and senses wall shear stress. In sepsis, EG undergoes degradation leading to increased permeability and edema formation. We hypothesized that restoring EG integrity using liposomal nanocarriers of preassembled glycocalyx (LNPG) will restore normal venular permeability in lipopolysaccharide (LPS)-induced sepsis model of mice. To test this hypothesis, we designed a unique perfusion microchamber in which the permeability of isolated venules could be assessed by measuring the concentration of Evans blue dye (EBD) in microliter samples of extravascular solution (ES). Histamine-induced time- and dose-dependent increases in EBD in the ES could be measured, confirming the sensitivity of the microchamber system. Notably, the histamine-induced increase in permeability was significantly attenuated by histamine receptor (H1) antagonist, triprolidine hydrochloride. Subsequently, mice were treated with LPS or LPS + LNPG. When compared with control mice, venules from LPS-treated mice showed a significant increased permeability, which was significantly reduced by LNPG administration. Moreover, in the presence of wall shear stress, intraluminal administration of LNPG significantly reduced the permeability in isolated venules from LPS-treated mice. We have found no sex differences. In conclusion, our newly developed microchamber system allows us to quantitatively measure the permeability of isolated venules. LPS-induced sepsis increases permeability of mesenteric venules that is attenuated by in vivo LNPG administration, which also reestablished endothelial responses to shear stress. Thus, LNPG presents a promising therapeutic potential for restoring EG function and thereby mitigating vasogenic edema due to increased permeability in sepsis.NEW & NOTEWORTHY In sepsis, the degradation of the endothelial glycocalyx leads to increased venular permeability. In this study, we developed a potentially new therapeutic approach by in vivo administration of liposomal nanocarriers of preassembled glycocalyx to mice, which restored venular sensitivity to wall shear stress and permeability in lipopolysaccharide-induced sepsis, likely by restoring the integrity of the endothelial glycocalyx. Using a new microchamber system, the permeability of Evans blue dye could be quantitatively determined.


Subject(s)
Capillary Permeability , Glycocalyx , Lipopolysaccharides , Liposomes , Sepsis , Stress, Mechanical , Animals , Glycocalyx/metabolism , Glycocalyx/drug effects , Capillary Permeability/drug effects , Lipopolysaccharides/toxicity , Venules/metabolism , Venules/physiopathology , Venules/drug effects , Male , Sepsis/physiopathology , Sepsis/metabolism , Sepsis/drug therapy , Mice , Mice, Inbred C57BL , Disease Models, Animal , Histamine/metabolism
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