TRAF6/ERK/p38 pathway is involved in interleukin-17-mediated autophagy to promote osteoclast precursor cell differentiation / 浙江大学学报·医学版

To investigate the effects of interleukin (IL)-17-mediated autophagy on the TNF receptor associated factor (TRAF6)/extracellular signal-regulated kinase (ERK)/p38 pathway and osteoclast differentiation. Mouse bone marrow-derived macrophages (BMM) were cultured with a medium containing 30 ng/mL macrophage colony stimulating factor and 50 ng/mL receptor activator of nuclear factor-kappa B ligard (RANKL), and IL-17 (0.01, 0.1, 1.0, 10 ng/mL) was added for intervention (IL-17 group). Tartrate-resistant acid phosphatase (TRAP) staining was used to observe TRAP positive multinucleated cells; phalloidin fluorescent staining was used to detect actin ring circumference; toluidine blue staining was used to analyze bone resorption lacuna formation. To further examine the mechanism of the effect of IL-17-mediated autophagy on the differentiation of osteoclasts, the control group used RANKL medium to culture mouse macrophage RAW264.7 cells, while the IL-17 group was treated with IL-17 (0.01, 0.1, 1.0, /mL). Western blot was used to detect the expression of autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3) and osteoclast-related proteins c-fos and nuclear factor of activated T cell 1 (NFATc1) after treatment with different concentrations of IL-17. The expression of LC3, NFATc1, TRAF6/ERK/p38 signaling pathway related proteins were detected in IL-17 and autophagy inhibitor 3-MA group. The number of TRAP positive multinucleated cells, the circumference of the actin ring and the area of bone resorption lacuna in IL-17 group treated with IL-17 (0.01, 0.1, were significantly higher than those in the control group. In IL-17 treated RAW264.7 cells, the expression of c-fos, NFATc1, Beclin-1, LC3, TRAF6, p-ERK, and p-p38 was all significantly up-regulated (all 0.05). After treatment with the autophagy inhibitor 3-MA, the expression levels of LC3, NFATc1, TRAF6, p-ERK, and p-p38 all decreased significantly (all 0.05). IL-17 can promote the expression of autophagy proteins and enhance the differentiation ability of osteoclast precursor cells, and the TRAF6/ERK/p38 signaling pathway may be involved in this process.

Advances in research of autophagy and its related proteins in periodontal disease / 中华口腔医学杂志

Periodontal disease is a chronic infectious disease characterized by gingival inflammation and progressive destruction of alveolar bone, and the interaction between plaque microbes and host defense affects the process of the disease. Recent studies have found that autophagy is one of the most primitive host defense responses against pathogenic microbial invasion. Autophagy plays an important role in the development of periodontal disease through such functions as clearing pathogens, regulating inflammatory responses and promoting osteoclast activation to affect bone resorption with inflammatory factors. This review article mainly introduces the research advances on autophagy mechanism and the relationship between autophagy and periodontal disease from the domestic and foreign literatures and expounds the mechanism of autophagy and periodontal pathogens, inflammatory reaction and bone resorption of osteoclasts, so as to enrich the pathogenesis of periodontal disease and provide a new perspective for the treatment of periodontal disease.

Effects of T helper 1 cells and T helper 17 cells secreting cytokines on rat models of experimental periodontitis / 中华口腔医学杂志

Objectvie@#To investigate the effects of secreting cytokines interferon-gamma (IFN-γ) and interleukin-17 (IL-17) of T helper 1 cells (Th1) and T helper 17 cells (Th17) on the peripheral blood and alveolar bone destruction, so as to provide a new explanation for cellular immunity-mediated alveolar bone destruction.@*Methods@#Eighteen eight-week-old male Sprague-Dawley rats were divided, randomly and equally, into 3 groups: lipopolysaccharide (LPS) group, ligation group and normal control group. In the LPS group, Escherichia coli LPS was injected into the alveolar mucosa on the buccalmedian site of the left upper first molar, while the right upper first molar was injected with equal volume of physiological saline as self-controls. The injections were performed every other day for four times totally. In the ligation group, the left upper first molars were ligatured with 0.2 mm orthodontic cords, while the right upper first molars were left untreated as self-controls, and supplemented with high-sugar diet to promote the periodontitis status. The rats in normal control group were fed normally. The concentrations of IFN-γ and IL-17 in peripheral blood were measured using enzyme linked immunosorbent assay (ELISA) method at the fourth week after the start of injection and at the eighth week after ligation. The histological of periodontal tissues were observed after hematoxylin-eosin (HE) staining and osteoclast count was performed under light microscope. The histological of osteoclasts were observed after tartrate-resistant acid phosphatase (TRAP) staining. Expression of IFN-γ and IL-17 were detected by immunohistochemical assay.@*Results@#The concentrations of IFN-γ in peripheral blood of LPS group [(185.0±50.7) ng/L] and ligation group [(202.9±60.4) ng/L] were significantly higher than that of normal control group [(106.3±17.2) ng/L](P<0.05). Meanwhile, histological examination showed inflammatory cells infiltration in the gingival epithelium, the height reduction of alveolar bone accompanied with absorption lacuna. There were significantly higher HE and TRAP stained osteoclasts in LPS group (9.50±1.05) and ligation group (10.83±1.17) than that in controlgroup (0.33±0.52)(P<0.05). Moreover, the expressions of IL-17 in alveolar bone absorption area of LPS group and ligation group were significantly stronger than that in control group (P<0.05).@*Conclusions@#The rat models of experimental periodontitis and alveolar bone resorption could be successfully established by means of ligationand LPS injection, respectively. The periodontal inflammatory responses were related to secreting cytokines IFN-γ and IL-17 of Th1 and Th17 cells, while Th17 cells might exert a positive effect on alveolar bone destruction.

AN INVESTIGATION ON NUTRITION AND DEVELOPMENT AND DISEASE OF CHILDREN UNDER AGE 2 IN SHANGHAI FACTORY NURSERIES / 营养学报

This paper is a follow-up study of 329 children in factory-run nurseries in urban Shanghai. The investigation lasted for a period of one year for each index-child, focusing on the conditions of nutrition, development and diseases of the children of various ages.Comparison between nutritionl findings and RDA of China disclosed that calorie intake of most of the index-child groups were 80-85% of RDA, the only exception being the 6-12 months group where the average calorie intake showed 90%. Protein intake of all groups was over 80% of RDA. Fe intake was lower than RDA, except for 18-month-old and over.Weight and height of the children were compared with the anthropo-metric data established in 1985 (1985 data) for Shanghai children under six years of age. It was found that the average weight and height appeared differently according to their age. Average weight of children under one year old was slightly higher than 1985 data, while average height was lower than 1985 data once the children reached 10 months old. Average weight, however, became lower than the 1985 data after the children were two years old. Over 60% of the index between 6-18 months old suffered from anemia (IDA).Accordingly, it is requested that calorie and iron intake should be supplemented.