ObjectiveTo investigate the effect of ambroxol hydrochloride on c-Jun N-terminal kinase (JNK) signal pathway in gastric aspiration lung injury. MethodsForty healthy male Sprague Dawley rats were randomly divided into a control group, an injury group, a SP600125 (JNK specific inhibitor) group and an ambroxol group. The model of gastric aspiration lung injury was established by aspiration of gastric contents. The rats in the SP600125 group preoperatively received intravenous injection of JNK specific inhibitor SP600125 (3 mg/100 g). The rats in the ambroxol group received intravenous injection of ambroxol hydrochloride (50 mg/kg) 2 hours after the damage occurred. The neutrophil count and malondialdehyde (MDA) activity in bronchoalveolar lavage fluid (BALF), the lung wet weight/dry weight ratio (W/D), and myeloperoxidase (MPO) activity were measured. The protein expressions of JNK and phosphorylated JNK (p-JNK) and inducible nitric oxide synthase (iNOS) in lung tissue were detected by Western blot method. The changes of lung tissue structure were observed under light microscope. ResultsIn the injury group, the neutrophil counts and MDA activity in BALF, W/D, MPO activity, p-JNK and iNOS protein expression increased significantly, lung tissue appeared obvious histopathological injury compared with the control group. In the SP600125 group and the ambroxol group, neutrophil count and MDA activity in BALF, lung W/D, MPO activity, p-JNK and iNOS protein expression were significantly decreased compared with the injury group (P < 0.05), and the damage of the lung tissue pathology was reduced. The expression of JNK protein in lung tissue was not different in all groups (P > 0.05). ConclusionsJNK is involved in inflammatory reaction of gastric aspiration lung injury. The protective effect of ambroxol may be related to the inhibition of JNK signaling pathway and the inhibition of iNOS expression.
In this study, the rescue effect of receptor activator for nuclear factor-κB ligand (RANKL) on zoledronate acid (ZOL) induced inhibition of osteoclastogenesis and gene expression of NF-κB p50 and c-Jun was investigated. Mice calvarial osteoblasts (OBs) were harvested and co-cultured with RAW264.7 cells and the cells were divided into 4 groups and received treatment with ZOL and RANKL, either single or combined. The formation of multi-nucleated osteoclast (OC) was examined and gene expression of NF-κB p50 and c-Jun was detected. Group B (ZOL) showed least multi-nucleated OC and resorption lacunae among the 4 groups (P<0.05 or P<0.01) and it was followed by group C (ZOL+RANKL). Group D (RANKL) showed highest OC and resorption lacunae while it was similar to Group A (control) (P>0.05). Gene expression of NF-κB p50 and c-Jun was the lowest in group B (P<0.05 or P<0.01) among the four groups and was significantly increased in group C when compared with group B (P<0.05). Group A and D showed highest gene expression and they were similar to each other (P>0.05). This study suggest that RANKL might partly rescue ZOL induced inhibition of osteoclastogenesis, and the effect of RANKL and ZOL on osteoclastogenesis may be mediated by NF-κB p50 and c-Jun.
Objective To investigate the influence of RNA interference targeting c-Jun gene on the proliferation of rat vascular smooth muscle cells (VSMCs). Methods The experiment was performed with c-Jun siRNA （c-Jun siRNA group）, control reverse sequence siRNA (control siRNA group) or no siRNA (control group). VSMCs were transfected with siRNA targeting c-Jun gene by liposome. Effects of c-Jun siRNA on mRNA and protein expressions of c-Jun were examined by RT-PCR analysis and Western blot respectively. MTT test and 3H-TdR incorporation were used to detect VSMCs proliferation. Cell cycle analysis of VSMCs in vitro was determined by flow cytometer. Results The expression levels of mRNA and protein of c-Jun in c-Jun siRNA group were significantly lower than those in control group （P＜0.05， P＜0.01). There was no significant difference between control group and control siRNA group （Pgt;0.05）. Proliferation activity of VSMCs decreased significantly in c-Jun siRNA group compared with that in control group （P＜0.05） and VSMCs was blocked in the G0/G1 phase of cell cycle significantly （P＜0.05）. There was no significant difference between control group and control siRNA group （Pgt;0.05）. Conclusion c-Jun gene silenced by RNA interference can inhibit VSMCs proliferation effectively in vitro.
OBJECTIVE: To observe the protein expression of phosphorylated form of P38 mitogen-activated protein kinase(P38MAPK) and c-Jun in hypertrophic scar skin and to explore their influences on the formation and maturation of hypertrophic scar. METHODS: The expression intensity and distribution of phosphorylated form of P38MAPK and c-Jun were examined with immunohistochemistry and pathological methods in 16 cases of hypertrophic scar skin and 8 cases of normal skin. RESULTS: In normal skin, the positive signals of phosphorylated form of P38MAPK mostly distributed in basal lamina cells of epidermis, while c-Jun was mainly located in epidermal cells and endothelial cells. The positive cellular rates of two proteins were 21.3% +/- 3.6% and 33.4% +/- 3.5% respectively. In proliferative hypertrophic scar skin, the particles of phosphorylated P38MAPK and c-Jun were mainly located in epidermal cells and some fibroblasts. The positive cellular rates of two proteins were significantly elevated to 69.5% +/- 3.3% and 59.6% +/- 4.3% respectively (P lt; 0.01). In mature hypertrophic scar, the expression of these proteins decreased but was still higher than that of normal skin. CONCLUSION: The formation and maturation of hypertrophic scar might be associated with the alteration of phosphorylated P38MAPK and c-Jun protein expression in hypertrophic scar.
Objective To observe the protein expression of c-Jun amino-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) in normal skin and keloid and to explore their influences on the formation of kloid. Methods Keloid tissues and normal skin tissues were collected from 16 keloid resection patients (experimental group) and 10 voluntary plastic surgery patients (control group). In the experimental group, the keloid formation time ranged from 8 months to 10 years; the keloid tissues were collected from the chest in 6 cases, the ear lobe in 4 cases, the perineum in 2 cases, the shoulder in 3 cases, and the abdomen in 1 case; and all keloid tissues were confirmed by pathological examination. In the control group, normal skin tissues were collected from the abdomen in 4 cases, the thighs in 3 cases, the shoulder in 2 cases, and the back in 1 case. Two-step l ine of Envision immunohistochemical staining was performed to observe the expressions of nonphosphorylated and phosphorylated JNK and ERK; Image Pro Plus 4.5 image analysis system was used to measure the integrated absorbance (IA) and to observe the positive staining strength. Results The immunohistochemical staining showed that no obvious expressions of phosphorylated and non-phosphorylated ERK, JNK were observed in the fibroblasts of the control group, and the expressions of phosphorylated JNK and ERK proteins were significantly higher in the experimental group than in the control group (P lt; 0.05). There was no significant difference in the expressions of non-phosphorylated JNK and ERK proteins between 2 groups (P gt; 0.05). Conclusion Activation of ERK and JNK pathways might be involved in formation of keloid.
目的 研究低碘飲食對大鼠甲狀腺功能的影響及c-Jun在腎組織中的表達差異，探討c-Jun在低碘大鼠腎臟組織中表達的意義。 方法 給予Wistar大鼠低碘飼料，通過飲用不同碘濃度飲水分組,測定甲狀腺功能。利用免疫組織化學方法分析腎臟組織中c-Jun的激活變化情況。 結果 重度低碘組與輕度低碘組、正常對照組比較三碘甲狀腺原氨酸(TT3)、血清總甲狀腺素(TT4)、游離三碘甲狀腺原氨酸(FT3)、游離甲狀腺素(FT4)均明顯下降(Plt;0.05)。輕度低碘組與正常對照組相比，TT4、FT3明顯下降(Plt;0.05)，TT3、FT4稍有降低(Pgt;0.05)。c-Jun在低碘大鼠腎組織中表達增強，與低碘程度有依賴關系，且在腎小球內的表達明顯強于腎小管。 結論 低碘攝入可引起腎組織中c-Jun的過度表達，進而引起腎臟損傷。
The gut mucus barrier and mechanical barrier are the most important natural barriers, the former is the first defense barrier, which separates pathogenic bacteria in intestinal lumen from the epithelial cells, and prevents them passing through the intestinal barrier into the human circulation system. Studies have shown that inflammation in the body affects the content of mucin 2, a key protein in the mucus layer, thereby changing the permeability of the mucus barrier and promoting the translocation of pathogenic microorganisms. Both tumor necrosis factor-α and c-jun N-terminal kinase signaling pathways have been reported to be closely related to the occurrence and development of inflammation. Therefore, this article reviews the relationship between tumor necrosis factor-α, c-jun N-terminal kinase signaling pathway and mucin 2 and intestinal barrier dysfunction, in order to provide new ideas and directions for exploring the related research of intestinal barrier function.