Study on the mechanism of electroacupuncture regulating macrophage polarization to improve ulcerative colitis in rats. / ç”µé’ˆè°ƒèŠ‚å·¨å™¬ç»†èƒžæžåŒ–æ”¹å–„å¤§é¼ æºƒç–¡æ€§ç»“è‚ ç‚Žçš„æœºåˆ¶ç ”ç©¶.

OBJECTIVES: To investigate the effect of electroacupuncture(EA) at "Changbing Decoction" on alleviating ulcerative colitis (UC) and regulating the polarization of colonic macrophages in rats, so as to explore its mechanisms underlying improvement of UC. METHODS: Twenty-six male SD rats were randomly divided into 4 groups：normal group(6 rats), model group(8 rats), EA group(6 rats), and western medication group(6 rats). The rat model of UC was established by using 5% dextran sulfate sodium (DSS) solution drinking water for 7 days, followed by drinking 1% DSS solution during treatment period. After 7-day model establishment, EA treatment(10 Hz/50 Hz, 20 min) was applied to "Zhongwan"(CV12), bilateral "Tianshu"(ST25) and "Shangjuxu"(ST37) for 3 d, and rats in the western medication group were given mesalazine suspension(200 mg/kg) by gavage for 3 d. The body weight, spleen weight and colon length of rats were measured. The disease activity index (DAI) score was evaluated. The morphological changes and inflammatory cell infiltration of colon were detected after HE staining and pathological scores were eva-luated. The contents of tumor necrosis factor α(TNF-α), interleukin(IL)-1ß, IL-2 and IL-10 in serum were detected by ELISA. The protein expressions of M1 and M2 macrophage markers nitric oxide synthase (iNOS) and arginase 1(Arg1) were detected by fluorescence double staining and Western blot, respectively. Quantitative real-time PCR was used to detect iNOS and Arg1 mRNA expressions. RESULTS: Compared with the normal group, rats in the model group had increased pathological damage degree and inflammatory cell infiltration in the colon tissue, slowed-down body weight gain, decreased colon length, spleen weight, serum anti-inflammatory factors IL-2 and IL-10 contents, colonic Arg1/CD68 fluorescence positive expression, and Arg1 protein and mRNA expressions(P<0.01, P<0.05), as well as increased DAI scores, colon histopathological scores, contents of serum pro-inflammatory factors TNF-α and IL-1ß, colonic iNOS/CD68 fluorescence positive expression, iNOS protein and mRNA expressions(P<0.01). Compared with the model group, the above indicators were significantly improved in rats of the EA group and the western medication group(P<0.01, P<0.05). CONCLUSIONS: EA of "Changbing Decoction" can improve UC of rats by regulating the polarization of colonic macrophages, inhibiting the generation of M1 macrophages and promoting the generation of M2 macrophages.

[Effect of electroacupuncture on colonic autophagy and AMPK/mTOR signaling pathway in rats with acute ulcerative colitis].

OBJECTIVE: To observe the effect of electroacupuncture （EA） at "Zhongwan" （CV12）, "Tianshu" （ST25） and "Shangjuxu" （ST37） （an acupoint prescription "Changbingfang" for treatment of intestinal disorders） on autophagy and expression of AMPK/mTOR signaling pathway in rats with ulcerative colitis （UC）, so as to explore its mechanism underlying improvement of UC. METHODS: Thirty-two male SD rats were randomly divided into control, model, medication and EA groups, with 8 rats in each group. The UC model was established by free drinking of 5% dextran sulfate sodium salt solution for 7 days. EA stimulation （10 Hz/50 Hz） was delivered to CV12, ST25 and ST37 for 20 min, once a day for 3 consecutive days. Rats of the medication group received gavage of mesalazine suspension （200 mg/kg） once a day, 3 times in total. The rats' general conditions were recorded for calculating the disease activity index （DAI） score （0-4 points）. Histomorphological changes of colon were observed via HE staining. The levels of serum interleukin 6 （IL-6）, tumor necrosis factor-α （TNF-α） and IL-10 were measured by ELISA. The mRNA expressions of LC3B and p62 were tested by fluorescence quantitative PCR. Western blot was used to detect the expression levels of LC3B, p62 and AMPK/mTOR pathway related proteins in colon tissues. RESULTS: Compared with the control group, the DAI score, contents of serum IL-6 and TNF-α, the expression levels of p62 protein and mRNA, ratio of p-mTOR/mTOR were significantly increased （P<0.01）； while the content of serum IL-10, the expression levels of LC3B mRNA, ratio of LC3BⅡ/LC3BⅠ and p-AMPK/AMPK were decreased （P<0.01, P<0.05） in the model group. Relevant to the model group, modeling-induced increases of DAI score, serum IL-6, TNF-α and IL-10 contents, expressions of p62 protein and mRNA, LC3B mRNA, ratio of p-mTOR/mTOR, LC3BⅡ/LC3BⅠ and p-AMPK/AMPK were reversed in both medication and EA groups （P<0.01, P<0.05）. The effect of EA was apparently superior to that of mesalazine in up-regulating ratio of LC3BⅡ/LC3BⅠ and p-AMPK/AMPK, p62 mRNA expression （P<0.01, P<0.05）, and in down-regulating ratio of p-mTOR/mTOR （P<0.05）. H.E. staining showed severe damage of the colonic mucosal barrier with infiltration of a large number of inflammatory cells in the model group, which was milder in medication and EA groups. CONCLUSION: EA of acupoint recipe "Changbingfang" can improve the symptoms in UC rats, which may be related to its functions in promoting colonic autophagy, increasing AMPK phosphorylation level, and decreasing mTOR phosphorylation level.

Single-step synthesis of highly photoluminescent carbon dots for rapid detection of Hg2+ with excellent sensitivity.

Carbon dots (C-dots) are superior in the aspects of excellent water solubility, good biocompatibility, environmentally friendliness and non-blinking fluorescence. In this work, highly photoluminescent small-size C-dots (QY = 18.8%, quinine sulfate as standard) with narrow size distribution (1.70 ±â€¯0.21 nm) have been synthesized by using citric acid and triethylamine through hydrothermal method. The optimal excitation and emission wavelength of C-dots are 350 nm and 437 nm, respectively. And the prepared C-dots display excitation-independent behavior due to less surface defects and uniform size. Interestingly, the fluorescence of C-dots could be rapidly and selectively quenched by Hg2+ within 200 s at room temperature without further modification. Under optimal conditions, the limit of detection (LOD) was measured to be nanomolar level (2.8 nM) with a linear range of 0.05-7 µM, lower than the previous published reports. Furthermore, our results reveal that static quenching mechanism was dominated in the process in which Hg2+ coordinate with the oxygen-containing groups of C-dots to form nonfluorescent complexes. And only the addition of Hg2+ destroyed the surface defects of C-dots resulting in the fluorescent quenching. The presence of other common interfering metal ions reported in previous literature (Ag+, Cu2+, Fe3+) do not affect the surface defects, which has rarely been reported before. Besides, this sensing platform has been further successfully applied to the label free detection of Hg2+ in tap water and living cells. These conclusions demonstrate the great potential of our C-dots in selective detection of environmental and cellular Hg2+, which may achieve a lot of achievements in clinical diagnosis and other biological researches.