OBJECTIVE: To explore the protective effect of glycosaminoglycans (GAG) on vascular endothelium in patients with sepsis. METHODS: A prospective study was conducted on adult patients with sepsis admitted to the intensive care unit (ICU) of Hangzhou Normal University Affiliated Hospital from December 2022 to December 2023. Patients were randomly divided into conventional treatment group and GAG intervention group. Both groups were treated according to the 2021 Surviving Sepsis Campaign Guidelines. The GAG intervention group was additionally treated with GAG (2 mL of sulodexide intramuscular injection once daily for 7 days) on the basis of conventional treatment. Venous blood was collected from patients at 0, 6, 24, 48, 72 hours and 7 days after enrollment to detect serum vascular endothelial glycocalyx [heparan sulfate (HS) and syndecan-1 (SDC-1)], inflammatory markers [C-reactive protein (CRP), procalcitonin (PCT), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6)], and coagulation markers [prothrombin time (PT), activated partial thromboplastin time (APTT), antithrombin-III (AT-III), fibrinogen (Fib), D-Dimer], and to perform acute physiology and chronic health evaluation II (APACHE II), sequential organ failure assessment (SOFA), and International Society on Thrombosis and Haemostasis (ISTH) scores. The prognosis of patients (length of hospital stay, ICU and 28-day mortality) was observed. The receiver operator characteristic curve (ROC curve) was drawn to evaluate the value of HS in predicting the prognosis of sepsis patients, and the correlation between endothelial glycocalyx degradation products and various clinical indicators was analyzed. RESULTS: A total of 50 adult patients with sepsis meeting the inclusion criteria were enrolled, with 25 in the conventional treatment group and 25 in the GAG intervention group. In terms of degradation products of endothelial glycocalyx, compared to baseline, both groups showed an increasing trend in HS and SDC-1 levels post-treatment. However, the GAG intervention group exhibited significantly lower HS levels at 72 hours and 7 days, as well as lower SDC-1 levels at 6, 24, 48, 72 hours and 7 days compared to the conventional group. Among the surviving patients, the HS levels at 72 hours and SDC-1 levels at 6 hours of treatment in the GAG intervention group were significantly reduced compared to the conventional treatment group. In terms of severity score, compared with before treatment, the GAG intervention group showed a significant decrease in APACHE II, SOFA, and ISTH scores after 7 days of treatment. The SOFA scores of the GAG intervention group after 48 hours and 7 days of treatment were significantly lower than those of the conventional treatment group. In terms of inflammatory indicators, compared with before treatment, the GAG intervention group showed a significant decrease in IL-6 levels after 48 hours of treatment. With the prolongation of treatment time, the CRP levels of both groups of patients showed a significant downward trend, and at 7 days of treatment, the CRP level in the GAG intervention group was significantly lower than that in the conventional treatment group. In terms of coagulation function, with prolonged treatment time, PT and APTT of both groups of patients showed an increasing trend, while Fib showed a decreasing trend. The GAG intervention group showed a significant prolongation of PT after 72 hours of treatment compared to the conventional treatment group. In terms of prognosis, there were no statistically significant differences in ICU and 28-day mortality rates between the two groups. The GAG intervention group had significantly shorter hospital stays than the conventional treatment group. ROC curve analysis showed that HS, CRP, APTT, IL-6, APACHE II, SOFA, and ISTH scores were predictive factors for the prognosis of sepsis patients (all P < 0.05). Compared to a single indicator, the combined detection of multiple indicators has a higher value in predicting the prognosis of sepsis patients [area under the curve (AUC) = 0.911, 95% confidence interval (95%CI) was 0.817-1.000], with a sensitivity of 76.9% and a specificity of 91.9%. Correlation analysis showed that HS was significantly negatively correlated with Fib, PT, TNF-α, IL-6, and PCT (r values were -0.338, -0.396, -0.288, -0.319, and -0.340, all P < 0.05), while HS was significantly positively correlated with D-Dimer and CRP (r values were 0.347 and 0.354, both P < 0.05); SDC-1 was significantly negatively correlated with Fib, PT, APTT, TNF-α, IL-6, and ISTH scores (r values were -0.314, -0.294, -0.408, -0.353, -0.289, -0.287, all P < 0.05). CONCLUSIONS Early glycocalyx degradation can occur in sepsis patients. GAG have a protective effect on,the vascular endothelium, reducing the severity of sepsis and providing organ protection. HS, CRP, APTT, IL-6, APACHE II score, SOFA score, and ISTH score are independent predictive factors for the prognosis of sepsis patients. The combination of HS and the above indicators can significantly improve the accuracy of prediction.
Humans ; Sepsis/blood* ; Glycocalyx/drug effects* ; Glycosaminoglycans/pharmacology* ; Prospective Studies ; Endothelium, Vascular/metabolism* ; Syndecan-1/blood* ; Male ; Female ; C-Reactive Protein/metabolism* ; Interleukin-6/blood* ; Heparitin Sulfate/blood* ; Middle Aged ; Adult ; Tumor Necrosis Factor-alpha/blood* ; Procalcitonin/blood*

OBJECTIVE: To investigate the interaction between α-amylase (α-AMS) and inflammatory response in patients with ventilator-associated pneumonia (VAP) and their predictive value for prognosis. METHODS: A prospective cohort study was conducted. Patients with mechanical ventilation who were treated in the intensive care unit (ICU) of the Second Hospital of Hebei Medical University from June 2020 to June 2023 were enrolled, and the patients were divided into VAP group and non-VAP group according to whether VAP occurred. VAP patients were stratified into mild [acute physiology and chronic health evaluation II (APACHE II) < 10 scores], moderate (APACHE II were 10-20 scores), and severe (APACHE II > 20 scores) groups based on the APACHE II. All patients were followed up for 28 days. In addition, healthy subjects who underwent health examination in our hospital at the same time were selected as the healthy control group. Baseline data including gender, age, mechanical ventilation mode, mechanical ventilation time, underlying diseases, drug use, and laboratory test indicators were collected. The serum levels of α-AMS, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C-reactive protein (CRP) and other inflammatory factors were analyzed and compared. Pearson correlation analysis was performed to analyze the correlation between serum α-AMS and inflammatory factors. Logistic regression was used to analyze the influencing factors of poor prognosis in patients with VAP. The receiver operator characteristic curve (ROC curve) was plotted to evaluate the predictive value of α-AMS on the poor prognosis of patients with VAP. RESULTS: A total of 100 mechanically ventilated patients were enrolled, including 60 cases in the VAP group and 40 cases in the non-VAP group. Among the patients with VAP, there were 24 cases in the mild group, 20 cases in the moderate group, and 16 cases in the severe group. A total of 44 patients survived at 28 days, while 16 died. Additionally, 100 healthy individuals were included as the healthy control group. Serum levels of α-AMS, IL-6, TNF-α and CRP in the VAP group were significantly higher than those in the non-VAP group and the healthy control group, while the levels of α-AMS, IL-6, TNF-α and CRP in the non-VAP group were significantly higher than those in the healthy control group. There were statistically significant differences in serum α-AMS, IL-6, TNF-α, CRP levels and APACHE II scores among VAP patients with different disease severities, and the levels of the above indicators in the severe group were significantly higher than those in the moderate group and mild group, and the levels of the above indicators in the moderate VAP group were significantly higher than those in the mild group. Pearson correlation analysis showed that serum α-AMS was positively correlated with IL-6, TNF-α, CRP, and APACHE II scores (r values were 0.404, 0.392 and 0.493, 0.493, all P < 0.01). Univariate analysis showed that age, mechanical ventilation, diabetes mellitus, ventilation time, ventilation position, prophylactic use of antimicrobial drugs, and serum α-AMS, IL-6, TNF-α, CRP, and APACHE II scores were correlated with the prognosis of VAP patients (all P < 0.05). Multivariate Logistic regression analysis identified age [odds ratio (OR) = 1.340, 95% confidence interval (95%CI) was 1.119-1.605], tracheostomy (OR = 3.050, 95%CI was 1.016-9.157), diabetes mellitus (OR = 1.379, 95%CI was 1.102-1.724), and ventilation time ≥ 7 days (OR = 2.557, 95%CI was 1.163-5.623) and serum α-AMS (OR = 1.428, 95%CI was 1.098-1.856), IL-6 (OR = 1.543, 95%CI was 1.005-2.371), TNF-α (OR = 2.228, 95%CI was 1.107-4.485), CRP (OR = 1.252, 95%CI was 1.131-1.387), APACHE II scores (OR = 1.422, 95%CI was 1.033-1.957) were independent influencing factors for the 28-day prognosis of patients with VAP (all P < 0.05). ROC curve analysis demonstrated that serum α-AMS, IL-6, TNF-α and CRP exhibited significant predictive performance on the prognosis of patients with VAP. The best cut-off value for α-AMS had a sensitivity of 81.3%, specificity of 75.0%, and an area under the ROC curve (AUC) of 0.791, which was significantly higher than those of inflammatory markers IL-6, TNF-α, and CRP (P < 0.05). The combined parameter diagnostic performance was significantly better than those of individual parameters (P < 0.05), with the highest diagnostic performance when combined, corresponding to an AUC of 0.868 (95%CI was 0.798-0.938), sensitivity of 87.5%, and specificity of 79.5%. CONCLUSIONS VAP in mechanically ventilated patients can lead to an increase in the levels of peripheral blood α-AMS and inflammatory factors, and there is an interaction between α-AMS and inflammatory markers in severe VAP patients. These markers are closely related to the severity of the disease and prognosis and have significant implications for predicting patient outcomes.
Humans ; Pneumonia, Ventilator-Associated/diagnosis* ; Prognosis ; Prospective Studies ; Respiration, Artificial ; alpha-Amylases/blood* ; Interleukin-6/blood* ; Male ; Female ; C-Reactive Protein/metabolism* ; APACHE ; Inflammation ; Middle Aged ; Intensive Care Units ; Tumor Necrosis Factor-alpha/blood* ; Aged

OBJECTIVE: To analyze the risk factors for ventilator-associated pneumonia (VAP) and its prognosis in patients with severe craniocerebral injury. METHODS: A prospective observational study was conducted. Patients with severe craniocerebral injury admitted to the Second Affiliated Hospital of Xingtai Medical College from January 2020 to December 2022 were enrolled as the study subjects. Patients were divided into VAP group and non-VAP group based on the occurrence of VAP. VAP patients were further stratified into low-risk group [sequential organ failure assessment (SOFA) score 0-5], moderate-risk group (SOFA score 6-8), and high-risk group (SOFA score ≥ 9). General data, serological indicators [interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and signal transducer and activator of transcription 3 (STAT3)], and 28-day prognosis (with mortality as the endpoint event) were compared. Multivariate Logistic regression was used to identify risk factors for VAP and 28-day mortality. Linear regression was applied to analyze the correlations between risk factors and outcomes. RESULTS: A total of 140 patients with severe craniocerebral injury were enrolled, including 49 in the VAP group and 91 in the non-VAP group. The primary cause of injury was traffic accidents, followed by falls and heavy object impacts. Among VAP patients, 38 survived and 11 died within 28 days; 112 were classified as low-risk, 25 as moderate-risk, and 12 as high-risk. Significant differences were observed in age, body mass index (BMI), smoking history, hypertension, diabetes, hyperlipidemia, length of hospital stay, duration of mechanical ventilation, serum albumin levels, and frequency of sputum suction among different subgroups. Serologically, IL-1β, TNF-α, IL-6, and STAT3 mRNA expression levels in the VAP group were significantly higher than those in the non-VAP group. Deceased VAP patients exhibited higher IL-1β, TNF-α, IL-6, and STAT3 mRNA levels compared to survivors. These biomarkers progressively increased from low-risk to high-risk subgroups. Multivariate Logistic regression identified age [odds ratio (OR) were 0.328 and 0.318], BMI (OR were 0.340 and 0.268), hypertension (OR were 0.275 and 0.245), diabetes (OR were 0.319 and 0.307), hyperlipidemia (OR were 0.228 and 0.235), smoking history (OR were 0.255 and 0.240), length of hospital stay (OR were 0.306 and 0.230), duration of mechanical ventilation (OR were 0.247 and 0.219), frequency of sputum suction (OR were 0.325 and 0.228), IL-1β (OR were 0.231 and 0.259), TNF-α (OR were 0.308 and 0.235), IL-6 (OR were 0.298 and 0.277), and STAT3 (OR were 0.259 and 0.265) as independent risk factors for both VAP occurrence and 28-day mortality (all P < 0.05). Correlation analysis revealed that serum albumin levels were negatively correlated with VAP occurrence and mortality (all P < 0.01), while other factors showed positive correlations (all P < 0.01). CONCLUSIONS Age, BMI, length of hospital stay, duration of mechanical ventilation, frequency of sputum suction, hypertension, diabetes, hyperlipidemia, smoking history, IL-1β, TNF-α, and IL-6/STAT3 signaling pathway activation are significantly associated with VAP development and poor prognosis in patients with severe craniocerebral injury, providing a scientific basis for targeted clinical interventions.
Humans ; Risk Factors ; Pneumonia, Ventilator-Associated ; Prognosis ; Prospective Studies ; Craniocerebral Trauma/complications* ; Interleukin-6/blood* ; Male ; Female ; STAT3 Transcription Factor/blood* ; Interleukin-1beta/blood* ; Tumor Necrosis Factor-alpha/blood* ; Middle Aged ; Adult ; Logistic Models

OBJECTIVE: To investigate the effects of liriodendrin on the intestinal flora and the ferroptosis signaling pathway in renal tissue of rats with sepsis-induced acute kidney injury (AKI). METHODS: Thirty male Sprague-Dawley (SD) rats were randomly divided into sham operation group (Sham group), sepsis model induced by cecal ligation and puncture group (CLP group), and liriodendrin intervention group (CLP+LIR group), with 10 rats in each group. The CLP+LIR group was given 0.2 mL of 100 mg/kg liriodendrin by gavage 2 hours before modeling; Sham group and CLP group were given the same volume of normal saline by gavage. The samples were collected after anesthesia 24 hours after modeling. The pathological changes of renal tissue were observed by hematoxylin-eosin (HE) staining. The levels of inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukins (IL-1β, IL-6) were detected by enzyme linked immunosorbent assay (ELISA). The levels of renal function indicators such as creatinine (Cr), and urea nitrogen (UREA) in peripheral blood, and the content of malondialdehyde (MDA) and Fe²⁺ in renal tissue were detected. Western blotting was used to detect the expressions of nuclear factor E2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4) and heme oxygenase-1 (HO-1) in renal tissues. The changes of intestinal flora were detected by 16S rDNA high-throughput sequencing. RESULTS: Compared with the Sham group, the CLP group showed significantly enlarged glomeruli, noticeable renal interstitial edema, disorganized kidney tissue, and significantly increased pathological scores. The contents of TNF-α, IL-1β, IL-6, Cr, and UREA in peripheral blood and the levels of MDA and Fe²⁺ in renal tissue were significantly increased. The protein expressions of Nrf2, GPX4, and HO-1 in renal tissue were significantly down-regulated. The species richness of intestinal flora decreased significantly, and the relative abundances of pathogenic bacteria such as Morganella, Citrobacter, Proteus, Klebsiella, Shigella, Aggregatibacter, and Enterococcus increased significantly, while the relative abundances of beneficial bacteria such as Butyricimonas, Veillonella, Prevotella, Lactobacillus, Bifidobacterium, and Ruminococcus decreased significantly. Compared with the CLP group, CLP+LIR group could significantly reduce the pathological damage of renal tissue, the pathological score significantly decreased (1.80±0.84 vs. 4.20±1.30, P < 0.05), and improve the composition of intestinal flora, reduce the relative abundances of pathogenic bacteria such as Proteus, Klebsiella, Shigella, Aggregatibacter, and Enterococcus, and significantly increase the relative abundances of Lactobacillus, Bifidobacterium, and Ruminococcus, significantly reduce the contents of TNF-α, IL-1β, IL-6, Cr, and UREA in peripheral blood and the levels of MDA and Fe²⁺ in renal tissue [blood TNF-α (ng/L): 191.31±7.23 vs. 254.90±47.89, blood IL-1β (ng/L): 11.15±4.04 vs. 23.06±1.67, blood IL-6 (ng/L): 163.20±17.83 vs. 267.69±20.92, blood Cr (μmol/L): 24.14±4.25 vs. 41.17±5.43, blood UREA (mmol/L): 4.59±0.90 vs. 8.01±1.07, renal MDA (μmol/g): 9.67±0.46 vs. 16.05±0.88, renal Fe²⁺ (mg/g): 0.71±0.07 vs. 0.93±0.04, all P < 0.05], and increase the protein expressions of Nrf2, GPX4, and HO-1 (Nrf2/GAPDH: 1.21±0.01 vs. 0.39±0.01, GPX4/GAPDH: 0.74±0.04 vs. 0.48±0.04, HO-1/GAPDH: 0.91±0.01 vs. 0.41±0.02, all P < 0.05). CONCLUSIONS Liriodendrin has an obvious protective effect on sepsis-induced AKI. The mechanism may involve regulating the intestinal flora, increasing the activation of the Nrf2/HO-1/GPX4 signaling pathway in renal tissue, and reducing ferroptosis.
Animals ; Acute Kidney Injury/microbiology* ; Rats, Sprague-Dawley ; Sepsis/complications* ; Male ; Ferroptosis/drug effects* ; Gastrointestinal Microbiome/drug effects* ; Rats ; Signal Transduction ; Kidney/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

Amoenucles A-F (1-6), six previously undescribed nucleoside derivatives, and two known analogs (7 and 8) were isolated from the culture of Aspergillus amoenus TJ507. Their structures were elucidated through spectroscopic analysis, single-crystal X-ray crystallography, and chemical reactions. Notably, 3 and 4 represent the first reported instances of nucleosides with an attached pyrrole moiety. Of particular significance, the absolute configuration of the sugar moiety of 1-4 was determined using nuclear magnetic resonance (NMR), electric circular dichroism (ECD) calculations, and a hydrolysis reaction, presenting a potentially valuable method for confirming nucleoside structures. Furthermore, 1, 2, and 5-8 exhibited potential tumor necrosis factor α (TNF-α) inhibitory activities, which may provide a novel chemical template for the development of agents targeting autoimmune and inflammatory diseases.
Aspergillus/chemistry* ; Tumor Necrosis Factor-alpha/antagonists & inhibitors* ; Molecular Structure ; Nucleosides/isolation & purification* ; Crystallography, X-Ray ; Animals ; Humans ; Mice ; Magnetic Resonance Spectroscopy

Microglia, the resident immune cells in the central nervous system (CNS), rapidly transition from a resting to an active state in the acute phase of ischemic brain injury. This active state mediates a pro-inflammatory response that can exacerbate the injury. Targeting the pro-inflammatory response of microglia in the semi-dark band during this acute phase may effectively reduce brain injury. Shionone (SH), an active ingredient extracted from the dried roots and rhizomes of the genus Aster (Asteraceae), has been reported to regulate the inflammatory response of macrophages in sepsis-induced acute lung injury. However, its function in post-stroke neuroinflammation, particularly microglia-mediated neuroinflammation, remains uninvestigated. This study found that SH significantly inhibited lipopolysaccharide (LPS)-induced elevation of inflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS), in microglia in vitro. Furthermore, the results demonstrated that SH alleviated infarct volume and improved behavioral performance in middle cerebral artery occlusion (MCAO) mice, which may be attributed to the inhibition of the microglial inflammatory response induced by SH treatment. Mechanistically, SH potently inhibited the phosphorylation of serine-threonine protein kinase B (AKT), mammalian target of rapamycin (mTOR), and signal transducer and activator of transcription 3 (STAT3). These findings suggest that SH may be a potential therapeutic agent for relieving ischemic stroke (IS) by alleviating microglia-associated neuroinflammation.
Animals ; Microglia/immunology* ; Mice ; Male ; Mice, Inbred C57BL ; Brain Ischemia/immunology* ; Neuroinflammatory Diseases/drug therapy* ; Neuroprotective Agents/administration & dosage* ; Interleukin-1beta/genetics* ; STAT3 Transcription Factor/genetics* ; TOR Serine-Threonine Kinases/genetics* ; Tumor Necrosis Factor-alpha/genetics* ; Proto-Oncogene Proteins c-akt/immunology* ; Nitric Oxide Synthase Type II/genetics* ; Lipopolysaccharides

Five new flavan-4-ol glycosides jixueqiosides A-E (1-5) and two new flavan glycosides jixueqiosides F and G (6 and 7), along with twelve known flavan-4-ol glycosides (8-19), were isolated from the roots of Pronephrium penangianum. Comprehensive spectral analyses, X-ray single-crystal diffraction, and theoretical electronic circular dichroism (ECD) calculations established structures and absolute configurations. A single crystal structure of flavan-4-ol glycoside (14) was reported for the first time, while the characteristic ECD and NMR data for all isolated flavan-4-ol glycosides (1-5 , 8-19) were analyzed, establishing a set of empirical rules. Activity screening of these isolates showed that 8 and 9 could inhibit the proliferation of MDA-MB-231 and MCF-7 cells with IC₅₀ values of 7.93 ? 2.85 ?mol?L^-1 and 5.87 ? 1.58 ?mol?L^-1 (MDA-MB-231), and 2.21 ? 1.38 ?mol?L^-1 and 3.52 ? 1.55 ?mol?L^-1 (MCF-7), respectively. Western blotting and flow cytometry analyses demonstrated that 8 and 9 dose-dependently induced apoptosis in MDA-MB-231 cells by up-regulating BAX, activating caspase-3 and down-regulating BCL-2. Additionally, compound 8 affected autophagy-related proteins, increasing the ratio of LC3-II/LC3-I and Beclin-1 levels to inhibit MDA-MB-231 cell proliferation. Moreover, anti-inflammatory studies indicated that 2, 3, 7, 13, 14, and 18 moderately inhibited tumor necrosis factor-a (TNF-a), interleukin-6 (IL-6), and nitric oxide (NO) release.
Humans ; Plant Roots/chemistry* ; Glycosides/isolation & purification* ; Anti-Inflammatory Agents/isolation & purification* ; Flavonoids/isolation & purification* ; Cell Proliferation/drug effects* ; Antineoplastic Agents, Phytogenic/isolation & purification* ; Molecular Structure ; Apoptosis/drug effects* ; Cell Line, Tumor ; Tumor Necrosis Factor-alpha/immunology* ; Drugs, Chinese Herbal/pharmacology* ; Interleukin-6/immunology* ; Animals ; Mice

Five meroterpenoids, rhodonoids K-M (1-2), daurichromene E (3), and grifolins A-B (4-5), together with seven known compounds (6-12), were isolated from Rhododendron anthopogonoides. The chemical structures of these compounds were elucidated through comprehensive analysis of high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), ultraviolet (UV), infrared spectroscopy (IR), and nuclear magnetic resonance (NMR) data. Their absolute configurations were determined by comparing experimental electronic circular dichroism (ECD) spectra with computed values. Notably, compounds 1 and 3 demonstrated significant inhibitory effects on lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells. These compounds markedly suppressed the mRNA expressions of inflammatory factors, including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) while also down-regulating the protein expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2).
Mice ; Rhododendron/chemistry* ; Animals ; Anti-Inflammatory Agents/isolation & purification* ; RAW 264.7 Cells ; Terpenes/isolation & purification* ; Molecular Structure ; Tumor Necrosis Factor-alpha/immunology* ; Cyclooxygenase 2/immunology* ; Nitric Oxide Synthase Type II/immunology* ; Macrophages/immunology* ; Interleukin-6/immunology* ; Lipopolysaccharides ; Interleukin-1beta/immunology*

Lirispirolides A-L (1-12), twelve novel sesquiterpene-monoterpene heterodimers featuring distinctive carbon skeletons, were isolated from the branches and leaves of Chinese tulip tree [Liriodendron chinense (L. chinense)], a rare medicinal and ornamental plant endemic to China. The structural elucidation was accomplished through comprehensive spectroscopic analyses, quantum-chemical calculations, and X-ray crystallography. These heterodimers exhibit a characteristic 2-oxaspiro[4.5]decan-1-one structural motif, biosynthetically formed through intermolecular [4 + 2]-cycloaddition between a germacrane-type sesquiterpene and an ocimene-type monoterpene. The majority of the isolated compounds demonstrated significant anti-neuroinflammatory effects in lipopolysaccharide (LPS)-induced BV-2 microglial cells by reducing the production of pro-inflammatory mediators, specifically tumor necrosis factor-α (TNF-α) and nitric oxide (NO). Further investigation revealed that the lirispirolides' inhibition of NO release correlated with decreased messenger ribonucleic acid (mRNA) expression of inducible NO synthase (iNOS).
Sesquiterpenes/isolation & purification* ; Anti-Inflammatory Agents/isolation & purification* ; Animals ; Mice ; Tumor Necrosis Factor-alpha/genetics* ; Nitric Oxide/immunology* ; Microglia/immunology* ; Molecular Structure ; Liriodendron/chemistry* ; Monoterpenes/isolation & purification* ; Plants, Medicinal/chemistry* ; Cell Line ; Lipopolysaccharides ; Nitric Oxide Synthase Type II/immunology* ; Plant Extracts/pharmacology* ; China

In continuation of research aimed at identifying anti-inflammatory agents from natural sesquiterpenoids, an activity-guided fractionation approach utilizing lipopolysaccharide (LPS)-mediated RAW264.7 cells was employed to investigate chemical constituents from Inula Britannica (I. britannica). Seven novel sesquiterpenoid dimers inulabritanoids A-G (1-7) and two novel sesquiterpenoid monomers inulabritanoids H (8) and I (9) were isolated from I. britannica together with eighteen known compounds (10-27). The structural elucidation was accomplished through comprehensive analysis of 1D and 2D nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HR-MS), and electronic circular dichroism (ECD) spectra, complemented by quantum chemical calculations. Compounds 1, 2, 12, 16, 19, and 26 demonstrated inhibitory effects on NO production, with IC₅₀ values of 3.65, 5.48, 3.29, 6.91, 3.12, and 5.67 μmol·L^-1, respectively. Mechanistic studies revealed that compound 1 inhibited IκB kinase β (IKKβ) phosphorylation, thereby blocking nuclear factor κB (NF-κB) nuclear translocation, and activated the kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signal pathway, leading to decreased expression of NADPH oxidase 2 (NOX-2), inducible nitric oxide synthase (iNOS), tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), IL-1β, and IL-1α and increased expression of NAD(P)H: quinone oxidoreductase 1 (NQO-1) and heme oxygenase-1 (HO-1), thus exhibiting anti-inflammatory effects in vitro. These results indicate that dimeric sesquiterpenoids may serve as promising candidates for anti-inflammatory drug development.
Mice ; Animals ; Sesquiterpenes/isolation & purification* ; Anti-Inflammatory Agents/isolation & purification* ; Inula/chemistry* ; RAW 264.7 Cells ; Nitric Oxide ; Molecular Structure ; NF-kappa B/immunology* ; NF-E2-Related Factor 2/immunology* ; Macrophages/immunology* ; Nitric Oxide Synthase Type II/immunology* ; Plant Extracts/pharmacology* ; Lipopolysaccharides ; Tumor Necrosis Factor-alpha/immunology* ; I-kappa B Kinase/genetics*