双歧杆菌对Treg/Th17细胞平衡及中国对虾蛋白致敏性的影响

目的通过体内实验研究婴儿双歧杆菌(Bifidobacterium infantis 13.085)和雷帕霉素对中国对虾原肌球蛋白致敏BALB/c小鼠过敏反应的治疗作用,从Treg/Th17细胞平衡及相关细胞因子角度探讨其缓解过敏的免疫调节作用机制。方法将中国对虾原肌球蛋白和弗氏佐剂混合液腹腔注射诱发BALB/c小鼠致敏,建立动物过敏模型。将实验小鼠随机分为正常对照组、致敏对照组、双歧杆菌治疗组、雷帕霉素治疗组。观察分析小鼠过敏症状,采用ELISA测定小鼠血清中特异性IgE、IgG2a的含量,采用流式细胞术测定脾脏T淋巴细胞亚群(Treg、Th17)数量,采用荧光定量PCR测定脾脏中Treg型和Th17型细胞因子和转录因子的表达量。结果第56天实验周期结束后结果发现,相比于致敏对照组,双歧杆菌和雷帕霉素治疗组小鼠过敏症状有明显的缓解,血清中特异性IgE显著降低(P0.05),脾脏Treg/Th17比值显著升高(P0.05),Th17型细胞因子IL-17A m RNA表达水平显著降低,Treg型细胞因子Foxp3 m RNA表达水平显著升高。此外,不同剂量的雷帕霉素治疗组缓解过敏反应存在剂量差异性。结论双歧杆菌13.085和雷帕霉素能有效缓解小鼠过敏症状,其作用可能通过平衡Treg/Th17细胞亚群数量,促进Treg型细胞因子表达而抑制Th17型细胞因子分泌有关。     

Hesperidin inhibits development of atopic dermatitis-like skin lesions in NC/Nga mice by suppressing Th17 activity

Hesperidin (previously called vitamin P) is a predominant flavanone present in citrus fruits, and is presumed to have a role in their beneficial effect for human health because it possesses various physiological activities. In this study, we investigated the anti-allergic and anti-inflammatory effects of hesperidin and α-glucopyranosyl (αG)-hesperidin, its derivative with enhanced water-solubility, in NC/Nga mice, a human-like mouse model of atopic dermatitis. NC/Nga mice were fed a 0.1% αG-hesperidin or hesperidin diet for 8 weeks. αG-hesperidin and hesperidin feeding effectively inhibited skin lesions and immunoglobulin E (IgE) elevation. At the end of the 8-week-experimental period, the production of inflammatory cytokine interleukin (IL)-17 and interferon-gamma (IFN-γ) from splenocytes was lower in the αG-hesperidin/hesperidin-fed group than in the control group. Changes in mRNA expression in splenocytes are also examined using DNA microarray and real-time RT-PCR. It was revealed that cytotoxic T-lymphocyte antigen 4 (CTLA4), a regulatory T-cell (Treg) marker, was markedly upregulated in splenocytes, particularly by αG-hesperidin feeding. These results suggest that αG-hesperidin attenuated exacerbation of AD-like symptoms, decreased systemic immune hyper-responsiveness in part through the reduction of IgE, IL-17 and IFN-γ, and also modulated Th17/Treg balance in NC/Nga mice. Therefore, αG-hesperidin may be useful in the management of Th17-mediated allergic disorders.     

具抗氧化功能益生菌菌株筛选及其对丙烯酰胺诱导肠上皮细胞氧化损伤的保护作用

为提高发酵蓝莓汁中的胞外多糖（exocytopolysaccharide,EPS）含量,以蓝莓为原料,选择三株高产胞外多糖的乳酸菌,采用单因素法、响应面法（RSM）对发酵条件进行优化,筛选出影响最大的四个因素：初始pH、接种量、发酵温度、发酵时间。在此基础上,采用人工神经网络（ANN）和遗传算法（GA）求解得到最佳发酵工艺条件为植物乳杆菌9sh、发酵乳杆菌SR2-6、柠檬明串珠菌GM11的菌种比例2:1:1,乳糖6%,大豆肽0.6%,蓝莓汁初始pH4.5,接种量8%,发酵温度30 ℃,发酵时间60 h,此时EPS含量为3.537 g/L。研究表明RSM和ANN可用于优化发酵蓝莓汁产EPS工艺。     

Hypolipidemic Activity of Peony Seed Oil Rich in α‐Linolenic,is Mediated Through Inhibition of Lipogenesis and Upregulation of Fatty Acid β‐Oxidation

Peony seed oil (PSO) is a new resource food rich in α‐Linolenic Acid(ALA) (38.66%). The objective of this study was to assess the modulatory effect of PSO on lipid metabolism. Lard oil, safflower oil (SFO), and PSO were fed to wistar rats with 1% cholesterol in the diet for 60 d. Serum and liver lipids showed significant decrease in total cholesterol (TC), triglyceride (TG), and low density lipoprotein‐cholesterol (LDL‐C) levels in PSO fed rats compared to lard oil and SFO fed rats. ALA, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), contents were significantly increased, whereas linoleic acid (LA), arachidonic acid (AA) levels decreased in serum and liver of PSO fed rats. Feeding PSO increased ALA level and decreased n‐6 to n‐3 polyunsaturated fatty acid (PUFA) ratio. The hypolipidemic result of PSO indicated that PSO participated in the regulation of plasma lipid concentration and cholesterol metabolism in liver. The decreased expression of sterol regulatory element‐binding proteins 1C (SREBP‐1c), acetyl‐CoA carboxylase (ACC), and fatty acid synthase (FAS)‐reduced lipid synthesis; Activation of peroxisome proliferator–activator receptor (PPARα) accompanied by increase of uncoupling protein2 (UP2) and acyl‐CoA oxidase (AOX) stimulated lipid metabolism and exerted an antiobesity effect via increasing energy expenditure for prevention of obesity.     

Regulation of lipid and glucose homeostasis by mango tree leaf extract is mediated by AMPK and PI3K/AKT signaling pathways

Ethanolic extract of Mangifera indica (mango) dose-dependently decreased serum glucose and triglyceride in KK-A^y mice. Our in vitro and in vivo investigations revealed that the effect of mango leave extract (ME) on glucose and lipid homeostasis is mediated, at least in part, through the PI3 K/AKT and AMPK signaling pathway. ME up-regulated the expression of PI3 K, AKT and GYS genes by 2.0-fold, 3.2-fold, and 2.7-fold, respectively, leading to a decrease in glucose level. On the other hand, ME up-regulated AMPK and altered lipid metabolism. ME also down-regulated ACC (2.8-fold), HSL (1.6-fold), FAS (1.8-fold) and PPAR-γ (4.0-fold). Finally, we determined that active metabolites of benzophenone C-glucosides, Iriflophenone 3-C-β-glucoside and Foliamangiferoside A from ME, may play a dominant role in this integrated regulation of sugar and lipid homeostasis.