1.Effects of VX765 on osteoarthritis and chondrocyte inflammation in rats.
Wanran HUANG ; Junxue TU ; Aiqing QIAO ; Chujun HE
Chinese Journal of Reparative and Reconstructive Surgery 2024;38(1):74-81
OBJECTIVE:
To investigate the effects and underlying mechanisms of VX765 on osteoarthritis (OA) and chondrocytes inflammation in rats.
METHODS:
Chondrocytes were isolated from the knee joints of 4-week-old Sprague Dawley (SD) rats. The third-generation cells were subjected to cell counting kit 8 (CCK-8) analysis to assess the impact of various concentrations (0, 1, 5, 10, 20, 50, 100 μmol/L) of VX765 on rat chondrocyte activity. An in vitro lipopolysaccharide (LPS) induced cell inflammation model was employed, dividing cells into control group, LPS group, VX765 concentration 1 group and VX765 concentration 2 group without obvious cytotoxicity. Western blot, real-time fluorescence quantitative PCR, and ELISA were conducted to measure the expression levels of inflammatory factors-transforming growth factor β 1 (TGF-β 1), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α). Additionally, Western blot and immunofluorescence staining were employed to assess the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1). Thirty-two SD rats were randomly assigned to sham surgery group (group A), OA group (group B), OA+VX765 (50 mg/kg) group (group C), and OA+VX765 (100 mg/kg) group (group D), with 8 rats in each group. Group A underwent a sham operation with a medial incision, while groups B to D underwent additional transverse incisions to the medial collateral ligament and anterior cruciate ligament, with removal of the medial meniscus. One week post-surgery, groups C and D were orally administered 50 mg/kg and 100 mg/kg VX765, respectively, while groups A and B received an equivalent volume of saline. Histopathological examination using HE and safranin-fast green staining was performed, and Mankin scoring was utilized for evaluation. Immunohistochemical staining technique was employed to analyze the expressions of matrix metalloproteinase 13 (MMP-13) and collagen type Ⅱ.
RESULTS:
The CCK-8 assay indicated a significant decrease in cell viability at VX765 concentrations exceeding 10 μmol/L ( P<0.05), so 4 μmol/L and 8 μmol/L VX765 without obvious cytotoxicity were selected for subsequent experiments. Following LPS induction, the expressions of TGF-β 1, IL-6, and TNF-α in cells significantly increased when compared with the control group ( P<0.05). However, intervention with 4 μmol/L and 8 μmol/L VX765 led to a significant decrease in expression compared to the LPS group ( P<0.05). Western blot and immunofluorescence staining demonstrated a significant upregulation of Nrf2 pathway-related molecules Nrf2 and HO-1 protein expressions by VX765 ( P<0.05), indicating Nrf2 pathway activation. Histopathological examination of rat knee joint tissues and immunohistochemical staining revealed that, compared to group B, treatment with VX765 in groups C and D improved joint structural damage in rat OA, alleviated inflammatory reactions, downregulated MMP-13 expression, and increased collagen type Ⅱ expression.
CONCLUSION
VX765 can improve rat OA and reduce chondrocyte inflammation, possibly through the activation of the Nrf2 pathway.
Rats
;
Animals
;
Chondrocytes/metabolism*
;
Matrix Metalloproteinase 13/metabolism*
;
Rats, Sprague-Dawley
;
Tumor Necrosis Factor-alpha/metabolism*
;
Collagen Type II/metabolism*
;
Interleukin-6
;
Lipopolysaccharides/pharmacology*
;
NF-E2-Related Factor 2/pharmacology*
;
Inflammation/drug therapy*
;
Osteoarthritis/metabolism*
;
Transforming Growth Factor beta1/metabolism*
;
Dipeptides
;
para-Aminobenzoates
2.IL-6 enhances the phagocytic function of mouse alveolar macrophages by activating the JAK2/STAT3 signaling pathway.
Mengqing HUA ; Peiyu GAO ; Fang FANG ; Haoyu SU ; Chuanwang SONG
Chinese Journal of Cellular and Molecular Immunology 2024;40(1):13-18
Objective To investigate the effect of interleukin-6 (IL-6) on the phagocytosis of MH-S alveolar macrophages and its related mechanisms. Methods A mouse acute lung injury (ALI) model was constructed by instilling lipopolysaccharide (LPS) into the airway. ELISA was used to detect the content of IL-6 in bronchoalveolar lavage fluid (BALF). In vitro cultured MH-S cells, in the presence or absence of signal transducer and activator 3 of transcription(STAT3) inhibitor Stattic (5 μmol/L), IL-6 (10 ng/mL~500 ng/mL) was added to stimulate for 6 hours, and then incubated with fluorescent microspheres for 2 hours. The phagocytosis of MH-S cells was detected by flow cytometry. Western blot analysis was used to detect the expression levels of phosphorylated Janus kinase 2 (p-JAK2), phosphorylated STAT3 (p-STAT3), actin-related protein 2 (Arp2) and filamentous actin (F-actin). Results The content of IL-6 in BALF was significantly increased after the mice were injected with LPS through the airway. With the increase of IL-6 stimulation concentration, the phagocytic function of MH-S cells was enhanced, and the expression levels of Arp2 and F-actin proteins in MH-S cells were increased. The expression levels of p-JAK2 and p-STAT3 proteins increased in MH-S cells stimulated with IL-6(100 ng/mL). After blocking STAT3 signaling, the effect of IL-6 in promoting phagocytosis of MH-S cells disappeared completely, and the increased expression of Arp2 and F-actin proteins in MH-S cells induced by IL-6 was also inhibited. Conclusion IL-6 promotes the expression of Arp2 and F-actin proteins by activating the JAK2/STAT3 signaling pathway, thereby enhancing the phagocytic function of MH-S cells.
Animals
;
Mice
;
Actins
;
Disease Models, Animal
;
Interleukin-6
;
Janus Kinase 2
;
Lipopolysaccharides
;
Macrophages, Alveolar
;
Signal Transduction
3.Fangji Fuling Decoction Alleviates Sepsis by Blocking MAPK14/FOXO3A Signaling Pathway.
Yi WANG ; Ming-Qi CHEN ; Lin-Feng DAI ; Hai-Dong ZHANG ; Xing WANG
Chinese journal of integrative medicine 2024;30(3):230-242
OBJECTIVE:
To examine the therapeutic effect of Fangji Fuling Decoction (FFD) on sepsis through network pharmacological analysis combined with in vitro and in vivo experiments.
METHODS:
A sepsis mouse model was constructed through intraperitoneal injection of 20 mg/kg lipopolysaccharide (LPS). RAW264.7 cells were stimulated by 250 ng/mL LPS to establish an in vitro cell model. Network pharmacology analysis identified the key molecular pathway associated with FFD in sepsis. Through ectopic expression and depletion experiments, the effect of FFD on multiple organ damage in septic mice, as well as on cell proliferation and apoptosis in relation to the mitogen-activated protein kinase 14/Forkhead Box O 3A (MAPK14/FOXO3A) signaling pathway, was analyzed.
RESULTS:
FFD reduced organ damage and inflammation in LPS-induced septic mice and suppressed LPS-induced macrophage apoptosis and inflammation in vitro (P<0.05). Network pharmacology analysis showed that FFD could regulate the MAPK14/FOXO signaling pathway during sepsis. As confirmed by in vitro cell experiments, FFD inhibited the MAPK14 signaling pathway or FOXO3A expression to relieve LPS-induced macrophage apoptosis and inflammation (P<0.05). Furthermore, FFD inhibited the MAPK14/FOXO3A signaling pathway to inhibit LPS-induced macrophage apoptosis in the lung tissue of septic mice (P<0.05).
CONCLUSION
FFD could ameliorate the LPS-induced inflammatory response in septic mice by inhibiting the MAPK14/FOXO3A signaling pathway.
Mice
;
Animals
;
Mitogen-Activated Protein Kinase 14/metabolism*
;
Wolfiporia
;
Lipopolysaccharides/pharmacology*
;
Sepsis/complications*
;
Signal Transduction
;
Inflammation/drug therapy*
;
Oxygen Radioisotopes
4.Protective Effects of Danmu Extract Syrup on Acute Lung Injury Induced by Lipopolysaccharide in Mice through Endothelial Barrier Repair.
Han XU ; Si-Cong XU ; Li-Yan LI ; Yu-Huang WU ; Yin-Feng TAN ; Long CHEN ; Pei LIU ; Chang-Fu LIANG ; Xiao-Ning HE ; Yong-Hui LI
Chinese journal of integrative medicine 2024;30(3):243-250
OBJECTIVE:
To investigate the effects of Danmu Extract Syrup (DMS) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice and explore the mechanism.
METHODS:
Seventy-two male Balb/C mice were randomly divided into 6 groups according to a random number table (n=12), including control (normal saline), LPS (5 mg/kg), LPS+DMS 2.5 mL/kg, LPS+DMS 5 mL/kg, LPS+DMS 10 mL/kg, and LPS+Dexamethasone (DXM, 5 mg/kg) groups. After pretreatment with DMS and DXM, the ALI mice model was induced by LPS, and the bronchoalveolar lavage fluid (BALF) were collected to determine protein concentration, cell counts and inflammatory cytokines. The lung tissues of mice were stained with hematoxylin-eosin, and the wet/dry weight ratio (W/D) of lung tissue was calculated. The levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1 β in BALF of mice were detected by enzyme linked immunosorbent assay. The expression levels of Claudin-5, vascular endothelial (VE)-cadherin, vascular endothelial growth factor (VEGF), phospho-protein kinase B (p-Akt) and Akt were detected by Western blot analysis.
RESULTS:
DMS pre-treatment significantly ameliorated lung histopathological changes. Compared with the LPS group, the W/D ratio and protein contents in BALF were obviously reduced after DMS pretreatment (P<0.05 or P<0.01). The number of cells in BALF and myeloperoxidase (MPO) activity decreased significantly after DMS pretreatment (P<0.05 or P<0.01). DMS pre-treatment decreased the levels of TNF-α, IL-6 and IL-1 β (P<0.01). Meanwhile, DMS activated the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathway and reversed the expressions of Claudin-5, VE-cadherin and VEGF (P<0.01).
CONCLUSIONS
DMS attenuated LPS-induced ALI in mice through repairing endothelial barrier. It might be a potential therapeutic drug for LPS-induced lung injury.
Mice
;
Male
;
Animals
;
Proto-Oncogene Proteins c-akt/metabolism*
;
Lipopolysaccharides
;
Phosphatidylinositol 3-Kinases/metabolism*
;
Interleukin-1beta/metabolism*
;
Vascular Endothelial Growth Factor A/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Claudin-5/metabolism*
;
Acute Lung Injury/chemically induced*
;
Lung/pathology*
;
Interleukin-6/metabolism*
;
Drugs, Chinese Herbal
5.Research advances in the mechanism of blood-brain barrier disruption by lipopolysaccharide and the onset of sepsis-associated encephalopathy
Journal of Apoplexy and Nervous Diseases 2024;41(1):77-83
As a barrier structure at the junction of the central nervous system (CNS) and the peripheral environment, the blood-brain barrier (BBB) successfully separates the circulating blood in brain tissue from the CNS and strictly controls material exchange between circulating blood and brain tissue, such as the transport of nutrients and the expulsion of metabolic wastes, thereby maintaining the homeostasis of the CNS. Lipopolysaccharide (LPS) is a component of the cell wall of Gram-negative bacteria and can impair the barrier function of the BBB and further promote the development and progression of sepsis-associated encephalopathy (SAE). This article reviews the mechanisms by which LPS injures the BBB via central links and other indirect links, as well as the association between these processes and SAE. We believe that when LPS causes damage to the BBB, a large number of immune cells and inflammatory factors enter brain tissue and activate immune cells of the brain, and even the neurovascular units that make up the BBB are affected and mediate the responses such as partial neuroinflammatory response and oxidative stress response, which causes further damage to the BBB. Such a vicious cycle eventually leads to the development of SAE, and therefore, we finally propose that targeted blockade of the disruption of BBB barrier function by LPS can be used for the prevention and treatment of SAE.
Lipopolysaccharides
6.Effect of acupuncture and moxibustion on intestinal flora in the rats with diarrhea-predominant irritable bowel syndrome based on 16S rDNA technique.
Bi-Yu LAI ; Meng-Ying HONG ; Yong-Jia HE ; Xing LI ; Shuang-Shuang WANG ; Yao CHEN ; Xin-Wu LI ; Jing NIE ; Dan LIU ; Chang SHE
Chinese Acupuncture & Moxibustion 2023;43(12):1411-1421
OBJECTIVES:
To explore the effect of acupuncture and moxibustion on intestinal flora in the rats with diarrhea-predominant irritable bowel syndrome (IBS-D) based on 16S rDNA technique.
METHODS:
Ten rats were randomized from 58 SPF-grade male SD rats to be the blank group. The remained 48 rats were prepared to be IBS-D models by the modified method of acetic acid enema combined with binding tail-clip stress. Forty successfully-modeled rats were randomly divided into a model group, an acupuncture group, a moxibustion group and a western medication group, with 10 rats in each one. In the acupuncture group, the needle was inserted at bilateral "Zusanli" (ST 36) and remained for 15 min in each rat. In the moxibustion group, the suspending moxibustion was delivered at bilateral "Zusanli" (ST 36) for 15 min. The rats in the western medication group were given pinaverium bromide suspension (10 mL/kg) by intragastric administration. The above interventions were performed once daily for consecutive 14 days. The body mass and the score of fecal trait were compared before and after modeling, as well as after intervention in each group. Fecal water content, diarrhea index and colon transit time (CTT) were measured after modeling and intervention in the rats of each group separately. After intervention, the colonic morphology of rats in each group was observed, and using 16S rDNA technique, the intestinal flora was detected.
RESULTS:
After modeling, compared with the blank group, the body mass and CTT were reduced (P<0.01); fecal trait scores, fecal water contents and diarrhea index increased (P<0.01) in the other 4 groups. After intervention, the body mass and CTT of the rats decreased (P<0.01), and fecal trait score, fecal water content and diarrhea index increased (P<0.01) in the model group compared with those in the blank group. In the acupuncture group, the moxibustion group and the western medication group, when compared with the model group, the body mass and CTT were elevated (P<0.01), while fecal trait scores, fecal water contents and diarrhea index declined (P<0.01). Compared with the western medication group, fecal water content decreased in the acupuncture group and the moxibustion group (P<0.05), while CTT increased in the acupuncture group (P<0.01), the body mass increased and fecal trait score was dropped in the moxibustion group (P<0.05). The colonic mucosa structure was clear and complete, and there was no obvious inflammatory cell infiltration in the blank group. The mild interstitial edema of intestinal mucosa was presented with the infiltration of few inflammatory cells in the model group. There was the infiltration of few inflammatory cells in the mucosa of the acupuncture group, the moxibustion group and the western medication group. Compared with the blank group, the indexes of Richness, Chao1, ACE and Shannon decreased in the model group (P<0.05). Indexes of Richness, Chao1 and ACE increased in the acupuncture group and the moxibustion group (P<0.05), and the Richness index in the western medication group increased (P<0.05) when compared with those in the model group. The relative abundance of Bacteroidetes, Proteobacteria and Prevotella increased (P<0.05), and that of Firmicutes and Muribaculaceae decreased (P<0.05) in the model group compared with those in the blank group. When compared with the model group, the relative abundance of Bacteroidetes, Proteobacteria and Prevotella was reduced (P<0.05), while that of Firmicutes and Muribaculaceae increased (P<0.05) in the acupuncture group, the moxibustion group and the western medication group; and that of Actinobacteria and Bifidobacterium increased in the acupuncture group and the moxibustion group (P<0.05). Compared with the blank group, the relative abundance of lipopolysaccharide (LPS) biosynthesis was elevated (P<0.05), and that of folate biosynthesis, lipoic acid metabolism, zeatin biosynthesis, ubiquinone and other terpenoid quinone biosynthesis decreased (P<0.05) in the model group. The relative abundance of LPS biosynthesis was dropped (P<0.05), and that of folate biosynthesis, lipoic acid metabolism, zeatin biosynthesis, ubiquinone and other terpenoid quinone biosynthesis increased (P<0.05) in the acupuncture group, the moxibustion group and the western medication group compared with those of the model group.
CONCLUSIONS
Either acupuncture or moxibustion can relieve the symptoms of IBS-D and protect intestinal mucosa, which may be associated with regulating the structure of intestinal flora and promoting nutrient metabolism and biosynthesis.
Rats
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Male
;
Animals
;
Irritable Bowel Syndrome/therapy*
;
Moxibustion/methods*
;
Rats, Sprague-Dawley
;
Gastrointestinal Microbiome
;
Lipopolysaccharides
;
Thioctic Acid
;
Ubiquinone
;
Zeatin
;
Acupuncture Therapy
;
Diarrhea/therapy*
;
Terpenes
;
Water
;
Folic Acid
;
Acupuncture Points
8.Liver macrophages show an immunotolerance phenotype in nonalcoholic fatty liver combined with Porphyromonas gingivalis-lipopolysaccharide infection.
Lijia GUO ; Yitong LIU ; Yingyi CHEN ; Junji XU ; Yi LIU
West China Journal of Stomatology 2023;41(4):385-394
OBJECTIVES:
This study aimed to explore the functions and potential regulatory targets of local macrophages in nonalcoholic fatty liver combined with Porphyromonas gingivalis (P. gingivalis)infection.
METHODS:
Single-cell RNA sequencing was used to analyze the phenotypes and functional changes in various cells in the liver tissue of nonalcoholic steatohepatitis (NASH) mice fed with P. gingivalis. Real-time polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay, and immunofluorescence staining were applied to observe the inflammation and expression levels of macrophage antigen presenting functional markers in the NASH liver. Oil red staining was performed to observe the accumulation of local adipose tissue in the NASH liver. Results were verified through RT-PCRand RNA sequencing using P. gingivalis-lipopolysaccharide treated mouse peritoneal macrophages.
RESULTS:
In comparison with healthy livers with Kupffer cells, the NASH liver combined with P. gingivalis infection-related macrophages showed significant heterogeneity. C1qb, C1qc, Mafb, Apoe, and Cd14 were highly expressed, but Cd209a, H2-Aa, H2-Ab1, and H2-DMb1, which are related to the antigen presentation function, were weakly expressed. Further in vivo and in vitro investigations indicated that the activation and infiltration of these macrophages may be due to local P. gingivalis-lipopolysaccharide accumulation.
CONCLUSIONS
P. gingivalis-lipopolysaccharide induces a local macrophage immunotolerance phenotype in nonalcoholic fatty liver, which may be the key mechanism of periodontitis pathogen infection that promotes NASH inflammation and pathogenesis. This study further clarifies the dysfunction and regulatory mechanisms of macrophages in the pathogenesis of P. gingivalis-infected NASH, thereby providing potential therapeutic targets for its clinical treatment.
Mice
;
Animals
;
Non-alcoholic Fatty Liver Disease/pathology*
;
Kupffer Cells/pathology*
;
Porphyromonas gingivalis
;
Lipopolysaccharides/metabolism*
;
Inflammation/pathology*
;
Macrophages/metabolism*
;
Mice, Inbred C57BL
9.Mechanism of bilobalide promoting neuroprotection of macrophages.
Yang-Yang CHEN ; Wen-Yuan JU ; Guo-Guo CHU ; Xiao-Hui LI ; Ru-Heng WEI ; Qing WANG ; Bao-Guo XIAO ; Cun-Gen MA
China Journal of Chinese Materia Medica 2023;48(15):4201-4207
This study aims to explore the neuroprotective effect of bilobalide(BB) and the mechanisms such as inhibiting inflammatory response in macrophage/microglia, promoting neurotrophic factor secretion, and interfering with the activation and differentiation of peripheral CD4~+ T cells. BB of different concentration(12.5, 25, 50, 100 μg·mL~(-1)) was used to treat the RAW264.7 and BV2 cells for 24 h. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay and cell counting kit-8(CCK-8) were employed to detect the cytotoxicity of BB and appropriate concentration was selected for further experiment. Lipopolysaccharide(LPS) was applied to elicit inflammation in RAW264.7 and BV2 cells, mouse bone marrow-derived macrophages(BMDMs), and primary microglia, respectively. The effect of BB on cell proliferation and secretion of inflammatory cytokines and neurotrophic factors was detected by enzyme-linked immunosorbent assay(ELISA). Spleen monocytes of C57BL/6 female mice(7-8 weeks old) were isolated, and CD4~+ T cells were separated by magnetic beads under sterile conditions. Th17 cells were induced by CD3/CD28 and the conditioned medium for eliciting the inflammation in BMDMs. The content of IL-17 cytokines in the supernatant was detected by ELISA to determine the effect on the activation and differentiation of CD4~+ T cells. In addition, PC12 cells were incubated with the conditioned medium for eliciting inflammation in BMDMs and primary microglia and the count and morphology of cells were observed. The cytoto-xicity was determined by lactate dehydrogenase(LDH) assay. The result showed that BB with the concentration of 12.5-100 μg·mL~(-1) had no toxicity to RAW264.7 and BV2 cells, and had no significant effect on the activity of cell model with low inflammation. The 50 μg·mL~(-1) BB was selected for further experiment, and the results indicated that BB inhibited LPS-induced secretion of inflammatory cytokines. The experiment on CD4~+ T cells showed that the conditioned medium for LPS-induced inflammation in BMDMs promoted the activation and differentiation of CD4~+ T cells, while the conditioned medium of the experimental group with BB intervention reduced the activation and differentiation of CD4~+ T cells. In addition, BB also enhanced the release of neurotrophic factors from BMDMs and primary microglia. The conditioned medium after BB intervention can significantly reduce the death of PC12 neurons, inhibit neuronal damage, and protect neurons. To sum up, BB plays a neuroprotective role by inhibiting macrophage and microglia-mediated inflammatory response and promoting neurotrophic factors.
Female
;
Rats
;
Mice
;
Animals
;
Bilobalides/pharmacology*
;
Neuroprotection
;
Lipopolysaccharides/toxicity*
;
Culture Media, Conditioned/pharmacology*
;
Mice, Inbred C57BL
;
Macrophages/metabolism*
;
Microglia
;
Cytokines/metabolism*
;
Nerve Growth Factors/pharmacology*
;
Inflammation/metabolism*
10.Comparison on anti-inflammatory activity of Gynostemma pentaphyllum processed with different methods.
Shu-Yang XU ; Zi-Qing YANG ; Fei TENG ; Xun-Jiang WANG ; Qin HUANG ; De-Zhen JIN ; Min LI ; Shou-Jin LIU ; Zheng-Tao WANG ; Li-Li DING ; Jing-Jing ZHU
China Journal of Chinese Materia Medica 2023;48(19):5235-5243
The aim of this study is to investigate the effects of Gynostemma pentaphyllum dried with two different methods(air drying and heating) on inflammation in acute lung injury(ALI) mice in vivo and in vitro. Lipopolysaccharide(LPS) was sprayed into the airway of wild type C57BL/6J male mice to establish the model, and the drug was injected into the tail vein 24 h after modeling. Lung function, lung tissue wet/dry weight(W/D) ratio, the total protein concentration, interleukin 6(IL-6), IL-1β, and tumor necrosis factor-α(TNF-α) in the bronchoalveolar lavage fluid(BALF), and pathological changes of the lung tissue were used to evaluate the effects of different gypenosides on ALI mice. The results showed that total gypenosides(YGGPs) and the gypenosides substituted with one or two glycosyl(GPs_(1-2)) in the air-dried sample improved the lung function, significantly lowered the levels of IL-1β and TNF-α in BALF, and alleviated the lung inflammation of ALI mice. Moreover, GPs_(1-2) had a more significant effect on inhibiting NO release in RAW264.7 cells. This study showed that different drying methods affected the anti-inflammatory activity of G. pentaphyllum, and the rare saponins in the air-dried sample without heating had better anti-inflammatory activity.
Male
;
Mice
;
Animals
;
Tumor Necrosis Factor-alpha/metabolism*
;
Gynostemma
;
Mice, Inbred C57BL
;
Lung
;
Anti-Inflammatory Agents/metabolism*
;
Interleukin-6/metabolism*
;
Interleukin-1beta/metabolism*
;
Lipopolysaccharides/pharmacology*

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