Chaihu Guizhi Decoction plus or minus formula combined with capecitabine inhibits IL-6/STAT3 signaling to suppress triple-negative breast cancer xenografts in nude mice / 南方医科大学学报

OBJECTIVE@#To investigate the effect of Chaihu Guizhi Decoction (CHGZD) combined with capecitabine on growth and apoptosis of subcutaneous triple-negative breast cancer xenografts in nude mice and explore the possible mechanism.@*METHODS@#Nude mouse models bearing subcutaneous triple-negative breast cancer xenografts were randomized into 6 groups (n=10) for treatment with distilled water (model group), low (10.62 g/kg), medium (21.23 g/kg) and high (42.46 g/kg) doses of CHGZD, capecitabine (0.2 mg/kg), or the combination of CHGZD (42.46 g/kg) and capecitabine (0.2 mg/k) once daily for 21 consecutive days. The general condition of mice was observed, and after 21-day treatments, the tumors were dissected for measurement of tumor volume and weight and histopathological examination with HE staining. Serum IL-6 levels of the mice were determined with enzyme-linked immunosorbent assay (ELISA), and the expression levels of IL-6, STAT3, p-STAT3, Bax, Bcl-2 and cyclin D1 in the tumor tissues were detected using real-time PCR and Western blotting.@*RESULTS@#Compared with those in the model group, the tumor-bearing mice receiving treatments with CHGZD showed significantly increased food intake with good general condition, sensitive responses, increased body weight, and lower tumor mass (P < 0.01). Compared with capecitabine treatment alone, treatment with CHGZD alone at the medium and high doses and the combined treatment all resulted in significantly higher tumor inhibition rates (P < 0.01), induced obvious tumor tissue degeneration and reduced the tumor cell density. Treatments with CHGZD, both alone and in combination with capecitabine, significantly decreased serum IL-6 level, lowered the mRNA expression levels of IL-6 and STAT3, the protein expressions of IL-6, STAT3 and P-STAT3 (P < 0.05), and the mRNA and protein expressions of Bcl-2 and cyclin D1 (P < 0.05), and increased the mRNA and protein expressions of Bax in the tumor tissues (P < 0.05).@*CONCLUSION@#CHGZD combined with capecitabine can significantly inhibit tumor growth in nude mice bearing triple-negative breast cancer xenografts, the mechanism of which may involve the inhibition of IL-6/STAT3 signaling pathway and regulation of Bax, Bcl-2 and cyclin D1 expressions to suppress tumor cell proliferation and differentiation and induce cell apoptosis.

Knocking-down Synaptotagmin 1 Attenuated Colitis via Suppressing the IL-6/STAT3 Signaling Pathway / 中国生物化学与分子生物学报

Synaptotagmin 1 (Sytl) is a member of the Synaptotagmin family and plays a role in neurotransmitter vesicle transport and exoeytosis. It has been reported that Sytl appears to be expressed in the intestinal epithelium, but the biological function of Sytl in colitis remains poorly understood. This study aimed to investigate the effects of Sytl in the inflammatory response and intestinal epithelial regeneration in colitis using Sytl transgenic mice and dextran sulfate sodium (DSS)-induced ulcerative colitis mode. qRT-PCR and Western blotting were employed to analyze the dynamic changes of Sytl in colitis. H&E staining, immunostaining and Western blotting were used to explore the roles of Sytl in the inflammatory response and in the regeneration and repair of intestinal epithelium in colitis. The results showed that the expression level of Sytl was indeed high in the colonic epithelium of wild-type mice and the intestinal epithelial cells of the adjacent tissues of colorectal cancer patients. Consistently, DSS-induced inflammation progressively resulted in marked upregulation of Sytl in the colon (P<0.01). In DSS-induced colitis, both the body weight loss and colonic shortening were dampened in Sytl loss-of-function mice compared with the control group (P < 0.05), while the number of regenerated crypts and Ki67 proliferating cells were also increased (P<0.01). Additionally, there were less infiltration of CD45 immune cells and F 4/80 macrophages and the expression of pro-inflammatory cytokines IL-6, TNFα and I L l-β, which were related with the severity of inflammation in the inflammatory bowel disease (I B D), were significantly decreased after Sytl deletion (P<0.05). Immunohistochemistry staining and Western blotting results further showed that IL-6 and p-STAT3 was significantly downregulated in Sytl knockdown mice (P<0.05). Taken together, these results suggested that knocking-down of Sytl may improve colitis by inhibiting the IL6/STAT3 signaling pathway.

Curcumin mediates IL-6/STAT3 signaling pathway to repair intestinal mucosal injury induced by 5-FU chemotherapy for colon cancer / 中国中药杂志

This study aims to investigate the potential mechanism of curcumin in mediating interleukin-6(IL-6)/signal transducer and activator of transcription 3(STAT3) signaling pathway to repair intestinal mucosal injury induced by 5-fluorouracil(5-FU) chemotherapy for colon cancer. SD rats were intraperitoneally injected with 60 mg·kg~(-1)·d~(-1) 5-FU for 4 days to establish a model of intestinal mucosal injury. Then the rats were randomly divided into model group(equal volume of normal saline), curcumin low, medium and high dose groups(50, 100, 200 mg·kg~(-1)), and normal SD rats were used as control group(equal volume of normal saline). Each group received gavage administration for 4 consecutive days, and the changes of body weight and feces were recorded every day. After administration, blood was collected from the heart, and jejunum tissues were collected. The levels of serum interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) were detected by ELISA, and at the same time, the concentration of Evans blue(EB) in jejunum was measured. Hematoxylin-eosin(HE) staining was used to observe the pathological state of jejunum, and the length of jejunum villi and the depth of crypt were measured. The positive expression levels of claudin, occludin and ZO-1 were detected by immunohistochemistry. Western blot was used to detect the protein expression of IL-6, p-STAT3, E-cadherin, vimentin and N-cadherin in jejunum tissues. The results showed that, curcumin significantly increased body weight and fecal weight(P<0.05 or P<0.01), decreased fecal score, EB concentration, IL-1β and TNF-α levels(P<0.05 or P<0.01) in rats. In addition, curcumin maintained the integrity of mucosal surface and villi structure of jejunum to a large extent, and reduced pathological changes in a dose-dependent manner. Meanwhile, curcumin could increase the positive expression of occludin, claudin and ZO-1(P<0.05 or P<0.01), repair intestinal barrier function, downregulate the protein expression of IL-6, p-STAT3, vimentin and N-cadherin in jejunum tissues(P<0.05 or P<0.01), and upregulate the protein expression of E-cadherin(P<0.05). Therefore, curcumin could repair the intestinal mucosal injury induced by 5-FU chemotherapy for colon cancer, and the mechanism may be related to the inhibition of IL-6/STAT3 signal and the inhibition of epithelial-mesenchymal transition(EMT) process.

Effect of moxibustion on IL-6/STAT3 signaling in frontal cortex of fatigue rats / 针刺研究

OBJECTIVE: To observe the effect of moxibustion on interleukin-6(IL-6)/signal transduction and transcriptional activator 3(STAT3) signaling pathway in the frontal cortex of fatigue rats, so as to reveal its mechanisms underlying alleviation of fatigue. METHODS: Twenty-one male SD rats were randomly divided into normal control, model, and moxibustion groups (n＝7 rats in each group). The fatigue model was established by forcing the rats to have an exhausted swim under load condition, once daily for 21 days. Moxibustion was applied to bilateral "Zusanli"(ST36) for about 15 min, once every other day for 21 days. The level of IL-6 in the frontal cortex was detected by ELISA, and the expression of Janus kinase 2 (JAK2), phosphorylated JAK2 (p-JAK2), signal transduction and transcriptional activator 3(STAT3) and phosphorylated STAT3 (p-STAT3) proteins in the frontal cortex was detected by Western blot. RESULTS: After modeling, the levels of IL-6 content and p-STAT3 protein expression and ratio of p-STAT3/STAT3 were significantly increased in the model group relevant to the normal control group (P0.05). CONCLUSION: Moxibustion intervention can relieve fatigue in fatigue rats, which is associated with its function in inhibiting IL-6/STAT3 signaling pathway to reduce inflammatory injury.