[A preliminary in vivo and in vitro study of endothelial cell pyroptosis in the periodontal inflammatory environment]

Objective: To observe whether endothelial cells undergo pyroptosis in the inflammatory periodontal environment by using a model in vivo and in vitro, providing an experimental basis for indepth understanding of the underlying pathogenesis of periodontitis. Methods: According to the classification of periodontal diseases of 2018, gingival tissues were collected from periodontally healthy subjects and patients with stage Ⅲ-Ⅳ, grade C periodontitis, who presented Department of Oral and Maxillofacial Surgery and Department of Periodontology, School of Stomatology, The Fourth Military Medical University from April to May 2022. Immunohistochemical staining was performed to detect the expression level and distribution of gasdermin D (GSDMD), a hallmark protein of cell pyroptosis, in gingival tissues. Periodontitis models were established in each group by ligating the maxillary second molar teeth of three mice for 2 weeks (ligation group). The alveolar bone resorption was determined by micro-CT (mice without ligation treatment were used as the control group), and the colocalization of GSDMD and CD31 were quantitatively analyzed by immunofluorescence staining in gingival tissues of healthy and inflammatory mice. Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and treated with lipopolysaccharide (LPS) of Porphyromonas gingivalis (Pg) combined with adenosine triphosphate (ATP) at various concentrations of 0.5, 1.0, 2.5, 5.0, and 10.0 mg/L, respectively, and the 0 mg/L group was set as the control group at the same time. Scanning electron microscopy was used to observe the morphology of HUVECs. Western blotting was used to detect the expression of gasdermin D-N terminal domains (GSDMD-N) protein and immunofluorescence cell staining was used to detect the expression and distribution of GSDMD. Cell counting kit-8 (CCK-8) was used to detect the proliferative ability of HUVECs, and propidium iodide (PI) staining was used to detect the integrity of cell membrane of HUVECs. Results: Immunohistochemistry showed that GSDMD in gingival tissues of periodontitis was mainly distributed around blood vessels and its expression level was higher than that in healthy tissues. Micro-CT showed that alveolar bone resorption around the maxillary second molar significantly increased in ligation group mice compared with control subjects (t=8.88, P<0.001). Immunofluorescence staining showed significant colocalization of GSDMD with CD31 in the gingival vascular endothelial cells in mice of ligation group. The results of scanning electron microscopy showed that there were pores of different sizes, the typical morphology of pyroptosis, on HUVECs cell membranes in the inflammatory environment simulated by ATP combined with different concentrations of LPS, and 2.5 mg/L group showed the most dilated and fused pores on cell membranes, with the cells tended to lyse and die. Western blotting showed that the expression of GSDMD-N, the hallmark protein of cell pyroptosis, was significantly higher in 2.5 and 5.0 mg/L groups than that in the control group (F=3.86, P<0.01). Immunofluorescence cell staining showed that the average fluorescence intensity of GSDMD in 2.5 mg/L group elevated the most significantly in comparison with that in the control group (F=35.25, P<0.001). The CCK-8 proliferation assay showed that compared to the control group (1.00±0.02), 0.5 mg/L (0.52±0.07), 1.0 mg/L (0.57±0.10), 2.5 mg/L (0.58±0.04), 5.0 mg/L (0.55±0.04), 10.0 mg/L (0.61±0.03) groups inhibited cell proliferation (F=39.95, P<0.001). PI staining showed that the proportion of positive stained cells was highest [(56.07±3.22)%] in 2.5 mg/L group (F=88.24, P<0.001). Conclusions: Endothelial cells undergo significant pyroptosis in both in vivo and in vitro periodontal inflammatory environments, suggesting that endothelial cell pyroptosis may be an important pathogenic factor contributing to the pathogenesis of periodontitis.

[Study on sIgE distribution characteristics and the sensitization pattern of allergen in 1 161 patients with allergic diseases of respiratory tract in northwest China]

Objective: To explore the allergen map of patients with allergic diseases in northwest China, to investigate the distribution characteristics of serum specific Immunoglobulin E (sIgE) in different ages, genders, diseases and the sensitization patterns of allergens. Methods: This study is a cross-sectional study, a total of 1 161 patients with confirmed respiratory allergic diseases were selected retrospectively from outpatient or inpatient department of Gansu Provincial People's Hospital, Gansu Provincial Maternity and Child Care Hospital, General Hospital of Ningxia Medical University, Yinchuan Maternal and Child Health Care Hospital, Xijing Hospital, Air Force Military Medical University and Tumor Hospital of Inner Mongolia Autonomous Region from June 2019 to October 2022. HAIKE ALLEOS 2000 fluorescent magnetic particle chemiluminescence method was used to quantify their serum for 12 inhaled allergen-specific IgE. Chi square test or Fisher's exact test were used for comparison between count data groups (Bonferroni correction was used for further pairwise comparison in multiple groups, two-sided P<0.05/3=0.017 considered that the difference was statistically significant). Pearson correlation analysis was used for correlation of continuous numerical variables. Results: The positive detection rate of sIgE in 1 161 patients was 66.8%(776/1 161). The three highest positive rate of inhaled allergen were mugwort(599/1 161, 51.6%), French chrysanthemum(565/1 161, 48.7%) and dandelion(412/1 161, 35.5%). In different age groups, the highest positive rate of sIgE was 7-18 age group(379/513, 73.9%) while the lowest positive rate was 4-6 age group(222/370, 60.0%), the difference between groups was statistically significant(χ2=21.177, P<0.001). The sensitization peak of mugwort, French chrysanthemum, plantain, timothy, birch, dermatophagoides pteronyssinus, dermatophagoides farinae, cat epithelium, dog epithelium and German cockroach appeared in 7-18 age group. In different disease groups, the highest positive rate of sIgE was allergic rhinitis with asthma group (500/717, 69.7%) while the lowest positive rate was asthma group (76/144, 52.8%), the difference between groups was statistically significant(χ2=15.563, P<0.001). In different gender groups, the positive rate of sIgE in male (503/711, 70.7%) was higher than in female (273/450, 60.7%), the difference between groups was statistically significant(χ2=12.630, P<0.001). The multiple-sensitization rate was 86.9%(674/776) and the double-sensitization rate was 16.8%(130/776) in sIgE positive patients. Pearson correlation results showed that there was an extremely strong correlation between dandelion and French chrysanthemum(r=0.93,P<0.001). There was a strong correlation between mugwort and French chrysanthemum(r=0.64,P<0.001). In the co-sensitization analysis, the number of patients sensitized by mugwort, French chrysanthemum, dandelion, plantain and timothy accounted for 25.2%(170/674)of the total number of multiple sensitization. The number of patients sensitized by mugwort, French chrysanthemum and dandelion accounted for 58.3%(393/674)of the total number of multiple sensitization. The number of patients sensitized by mugwort, French chrysanthemum, dandelion and plantain accounted for 35.6%(240/674) of the total number of multiple sensitization. Conclusion: Mugwort, French chrysanthemum, dandelion are the major inhaled allergens in northwest China. The positive rate of sIgE was different in different ages, diseases and genders. The multiple-sensitization rate of allergen was high and there was a certain positive correlation between pollen allergen-specific IgE pairwise, suggesting that there may exist co-sensitization or cross-reactions among allergens.

Efficacy and safety of combined Chinese and Western medicine in the treatment of knee osteoarthritis: a prospective, multicenter cohort study

Purpose: To conduct a real-world evaluation of the efficacy and safety of combined Chinese and Western medicine in treating knee osteoarthritis (KOA). Methods: A multicenter, prospective cohort study design was employed, enrolling 450 KOA patients (Kellgren-Lawrence score of 3 or less). The patients were divided into a Western medicine treatment group (WM group) and a combined Western and traditional Chinese medicine treatment group (WM-CM group). A 6-week treatment plan was administered, and follow-up visits occurred at 2 weeks, 4 weeks, and 6 weeks after initiating treatment. The primary outcome indicator was the total Western Ontario and McMaster Universities Arthritis Index (WOMAC) score after 6 weeks of treatment. Secondary outcome indicators included WOMAC subscales for pain, stiffness, and joint function, visual analogue scale (VAS) score, physical component summary (PCS), mental component summary (MCS), and clinical effectiveness. The incidence of drug-related adverse events was used as a safety evaluation indicator. Results: A total of 419 patients were included in the final analysis: 98 in the WM group and 321 in the WM-CM group. The baseline characteristics of the two groups were comparable, except for the incidence of stiffness symptoms and stiffness scores. After 6 weeks of treatment, the WM-CM group exhibited superior results to the WM group in improving the total WOMAC score (24.71 ± 1.38 vs. 16.36 ± 0.62, p < 0.001). The WM-CM group also outperformed the WM group in WOMAC pain and joint function scores, VAS score, PCS score, MCS score, and clinical effectiveness (p < 0.05), which was consistent with the findings of the main evaluation index. Subgroup analysis indicated that the combined Chinese and Western medicine treatment showed more pronounced benefits in patients under 65 years of age and in those with a Kellgren-Lawrence (K-L) classification of 0-I. Throughout the study, no adverse effects were observed in either group. Conclusion: The combination of Chinese and Western medicine demonstrated superiority over Western medicine alone in relieving knee pain symptoms, improving knee function, and enhancing the quality of life for KOA patients with a K-L score of 3 or less. Moreover, the treatment exhibited a good safety profile. Clinical Trial Registration: (https://www.chictr.org.cn/), identifier (ChiCTR1900027175).

[Mesenchymal stem cells derived apoptotic extracellular vesicles attenuate pro-inflammatory macrophages induced by Porphyromonas gingivalis lipopolysaccharide]

Objective: To investigate whether bone marrow mesenchymal stem cells (BMMSCs) derived apoptotic extracellular vesicles (ApoEVs) could regulate the polarization of mouse macrophage cell line RAW264.7 and whether BMMSCs derived ApoEVs could attenuate pro-inflammatory condition of RAW264.7 induced by Porphyromonas gingivalis lipopolysaccharide (Pg-LPS), so as to provide experimental evidence and theoretical basis for using BMMSCs derived ApoEVs as a method to treat periodontitis. Methods: The Operetta CLS high-content analysis system was used to observe the time-dependent apoptosis process of BMMSCs. Besides, field emission scanning electron microscopy (FESEM), dynamic light scattering technology and streaming potential method were used to measure the surface characteristics of BMMSCs derived ApoEVs. The Operetta CLS high-content analysis system was used to observe the process of RAW264.7 phagocyting 5-carboxy-tetramethylrhodamine, succinimidyl ester (5-TAMRA-SE) labeled ApoEVs. Real-time quantitative PCR was used to detect the mRNA expression of arginase-1 (Arg-1). Cell immunofluorescence and Western blotting were used to detect the number of inducible nitric oxide synthase (iNOS)(+) macrophages and iNOS protein expression level in each experiment group. Enzyme linked immunosorbent assay was used to detect tumor necrosis factro-α (TNF-α) level in the Pg-LPS induced pro-inflammatory macrophage culture supernatant in each experiment group. Results: After treating with 0.5 μmol/L staurosporine for 12 hours, mouse BMMSCs underwent shrinking with obvious vesicles structure around. The FESEM showed the ApoEVs were in spherical shapes. The size range of ApoEVs was about 100-1 000 nm and the average Zeta potential was -16.6 mV. The Operetta CLS high-content analysis system showed RAW264.7 could phagocytose 5-TAMRA-SE labeled ApoEVs by pseudopodia. The relative mRNA expression of Arg-1 was significantly increased in RAW 264.7 after being treated with interleukin 4 (IL-4) and ApoEVs (261.97±15.91) compared to that with IL-4 alone (115.29±15.42) (P<0.01). Cell immunofluorescence showed that ApoEVs could reduce the number of iNOS(+) macrophages induced by Pg-LPS (39.33±4.70) comparing to those without ApoEVs (95.33±4.70) (P=0.007). In the meanwhile, ApoEVs could also down-regulate the iNOS protein level of macrophages induced by Pg-LPS (5.84±1.05) comparing to those without ApoEVs (14.91±3.87) (P<0.01). Besides, ApoEVs could also reduce the TNF-α secretion in the culture supernatant of pro-inflammatory macrophages induced by Pg-LPS [(21 899.71±409.73) ng/L] comparing to those without ApoEVs [(71 296.50±2 344.22) ng/L] (P=0.003). Conclusions: BMMSCs derived ApoEVs could regulate the polarization of macrophages and could also attenuate the pro-inflammatory condition of macrophages induced by Pg-LPS.