【摘要】：本論文通過飼喂小鼠高脂飼料和灌胃不同濃度的約氏乳酸桿菌BS15,來探討約氏乳酸桿菌BS15對高脂飼料引起的肥胖和非酒精性脂肪肝的作用,并研究其機理。選用120只雄性ICR小鼠,試驗前35d小鼠分為三組,ND組60只小鼠均灌胃磷酸緩沖生理鹽水(PBS), L-BS15組和H-BS15組各30只分別灌胃不同濃度約氏乳酸桿菌BS15(2×107或2×108 cfu/d),均給予普通飼料(NCD)。上述處理35d后將ND組小鼠分出一半,分出小鼠飼喂高脂飼料和灌胃PBS為HFD組,其余小鼠繼續(xù)飼喂NCD和灌胃PBS仍為ND組；L-BS15組和H-BS15組小鼠改喂高脂飼料同時繼續(xù)灌胃不同濃度約氏乳酸桿菌BS15,持續(xù)12周。在第35、63、91、119d采取小鼠樣本進行檢測,試驗結果如下：1.與ND組小鼠相比,HFD組體重顯著升高；與HFD組相比,L-BS15和H-BS15組小鼠體重顯著降低。2.肝臟病理組織學切片觀察,HFD組小鼠肝臟內空泡化嚴重,肝臟脂肪變性較L-BS15和H-BS15組顯著。3.通過流式細胞技術(FCM)對小鼠肝臟細胞進行檢測,與ND組相比,HFD小鼠肝臟細胞凋亡率顯著升高；L-BS15和H-BS15組肝臟細胞凋亡率較HFD組顯著降低。4.實時熒光定量(RT-PCR)技術檢測小鼠盲腸內容物特定菌群發(fā)現,BS15的補充顯著增加了腸道內乳酸菌、約氏乳酸桿菌及擬桿菌的數量,同時降低了腸道內腸桿菌和厚壁桿菌門／擬桿菌門的比例,有效改善了高脂飼料誘導的腸道菌群的紊亂。5.實時熒光定量(RT-PCR)技術檢測小鼠肝臟內脂肪代謝相關因子(ACC1、 FAS、FIAF、PPARy)基因表達發(fā)現,與ND組相比,HFD組ACC1、FAS和PPARy基因表達量顯著升高,FIAF表達量顯著降低；灌胃BS15后,ACC1、FAS和PPARγ基因表達量較HFD組顯著降低,FIAF表達量顯著升高。6.腸道通透性試驗表明,高脂飼料顯著誘導了HFD組小鼠腸道通透性；BS15的補充顯著降低了小鼠腸道通透性。7.機體炎癥相關指標檢測表明,HFD組小鼠血清中LPS含量和肝臟組織TNF-α表達水平在119 d顯著高于ND組。灌胃BS15后,與HFD組相比,血清LPS含量和肝臟TNF-α表達量在L-BS15組和H-BS15組顯著降低。與ND組相比,從第63d到119d小鼠血清中C反應蛋白(CR_P)含量在HFD組顯著升高。灌胃BS15后,與HFD組相比,從第63d到119d小鼠血清中CRP含量在L-BS15組和H-BS15組顯著降低。BS15顯著降低了高脂飼料誘導的機體炎癥。8.小鼠胰島素抗性檢測發(fā)現,與ND組相比在第63、91、119 d, HFD組小鼠血清中胰島素含量和胰島素抗性均顯著升高,灌胃BS15后,小鼠血清中胰島素含量及胰島素抗性在63、91、119d三個檢測點均顯著降低。與ND組相比,小鼠血清中TG、TC、LDL-C、ALT、FFA含量在HFD組顯著升高,HDL-C含量在HFD組顯著降低。灌胃BS15后,與HFD組相比,TG、LDL-C、ALT、FFA含量顯著降低,HDL-C含量顯著升高。BS15的補充抑制了胰島素抗性的產生及血脂指標的紊亂。9.氧化應激相關指標檢測發(fā)現,與ND組相比HFD組肝臟線粒體和肝細胞胞漿中H2O2、GSH和MDA含量均顯著升高,CAT、GSH-PX和T-SOD酶活力在線粒體和胞漿中顯著降低。灌胃BS15后與HFD組相比,L-BS15組和H-BS15組線粒體內H2O2、GSH和MDA含量均顯著降低,CAT和GSH-PX酶活力顯著升高,T-SOD酶活力變化不顯著。與HFD組相比,L-BS15組和H-BS15組胞漿內H2O2、GSH含量均顯著降低,MDA、T-SOD酶活力顯著升高,CAT、GSH-PX酶活力僅在H-BS15組內升高顯著。BS15的補充有利于抑制肝臟組織氧化應激的發(fā)生。綜上所述,約氏乳酸桿菌BS15具有抗肥胖和預防非酒精性脂肪肝的作用,其主要機理是通過改善腸道菌群,降低腸道通透性、機體炎癥、肝臟氧化應激和胰島素抵抗。
[Abstract]:In order to investigate the effect of Lactobacillus casei BS15 on obesity and non-alcoholic fatty liver induced by high fat feed, the mechanism was studied by feeding mice with high fat feed and Lactobacillus bulgaricus BS15 at different concentrations. A total of 120 male ICR mice were divided into three groups, and 60 mice in ND group were given oral phosphate buffered saline (PBS), and 30 rats in L-B15 group and H-BS15 group were respectively given different concentrations of Lactobacillus bulgaricus BS15 (2, 107 or 2, 108 cfu/ d), all of which were given normal feed (NCD). After 35d treatment, the ND group mice were divided into half, the mice were fed with high fat feed and PBS as HFD group, the remaining mice continued to feed NCD and gavage PBS were still ND group; L-BS15 group and H-BS15 group mice were fed with high fat feed while continuing to gavage at different concentrations of Lactobacillus bulgaricus B15 for 12 weeks. Mice samples were tested on Days 35, 63, 91, 119d and the results were as follows: 1. Compared with the ND group, the body weight of the HFD group increased significantly; compared with the HFD group, the body weight of the L-B15 and H-B15 groups decreased significantly. The pathological histological sections of liver showed that the vacuolization of liver was severe in HFD group, and the fatty degeneration of liver was higher than that in L-BS15 and H-BS15 group. The liver cells of mice were detected by flow cytometry (FCM). Compared with ND group, the apoptosis rate of liver cells in HFD mice increased significantly, and the apoptosis rate of liver cells in L-B15 and H-B15 groups was significantly lower than that in the HFD group. The real-time fluorescence quantitative (RT-PCR) technique is used for detecting the specific flora of the cecum contents of the mice, and the supplementation of the B15 remarkably increases the number of lactic acid bacteria in the intestinal tract, the lactobacilli and the pseudo-bacillus, and simultaneously reduces the proportion of the enterobacteriaceae and the thick-walled bacillus door/ planned bacillus door in the intestinal tract, effectively improving the disorder of intestinal flora induced by high fat feed. The expression of ACC1, FAS, FIAF, PPARy in liver of mice was detected by real-time fluorescence quantitative (RT-PCR) technique. Compared with the HFD group, the expression level of the FAS and Jurkat gene was significantly decreased, and the expression level of FIF increased significantly. The intestinal permeability test showed that the high fat diet significantly induced intestinal permeability in the HFD group, and the supplementation of B15 significantly reduced the intestinal permeability of mice. The results showed that the expression level of LPS in serum of HFD group and liver tissue was significantly higher than that of ND group in HFD group. Compared with the HFD group, the expression levels of LPS and liver TNF-B15 decreased significantly in the L-B15 group and the H-B15 group compared with the HFD group. Compared with ND group, the content of C-reactive protein (CR _ P) in serum of mice from 63d to 119d increased significantly in the HFD group. Compared with the HFD group, the CRP levels in the serum of mice from 63d to 119d were significantly lower in the L-B15 group and in the H-B15 group than in the HFD group after gavage of B15. BS15 significantly reduced body inflammation induced by high fat feed. Compared with ND group, the insulin content and insulin resistance in serum of mice were significantly increased compared with ND group, and the insulin content and insulin resistance in serum of mice were significantly decreased at 63, 91 and 119d after intragastric administration of B15. Compared with ND group, the content of TG, TC, LDL-C, ALT and HDL in serum of mice increased significantly in HFD group, and HDL-C content decreased significantly in HFD group. After intragastric administration of BS15, TG, LDL-C, ALT, HDL-C content were significantly decreased compared with HFD group, and HDL-C content increased significantly. The addition of B15 inhibited the generation of insulin resistance and disorder of blood lipid index. Compared with ND group, the content of H2O2, GSH and MDA in liver mitochondria and liver cell cytoplasm of HFD group increased significantly compared with ND group, CAT, GSH-PX and T-SOD activity decreased significantly in mitochondria and cytoplasm. Compared with HFD group, the contents of H2O2, GSH and MDA in the mitochondria of L-BS15 and H-BS15 groups were significantly decreased compared with the HFD group, but the activity of CAT and GSH-PX increased significantly, and the activity of T-SOD was not significant. Compared with HFD group, the content of H2O2 and GSH in plasma of L-BS15 group and H-BS15 group decreased significantly, MDA, T-SOD activity increased significantly, CAT, GSH-PX activity increased significantly in H-BS15 group. The supplementation of B15 is beneficial to inhibit the occurrence of oxidative stress in liver tissues. In conclusion, Lactobacillus casei BS15 has the function of resisting obesity and preventing non-alcoholic fatty liver, and its main mechanism is to improve intestinal flora, reduce intestinal permeability, body inflammation, liver oxidative stress and insulin resistance.
【學位授予單位】：四川農業(yè)大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：R575.5;R589.2

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1 辛金鴿;約氏乳酸桿菌BS15對小鼠脂肪沉積和非酒精性脂肪肝的影響[D];四川農業(yè)大學;2014年

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本文編號：2262814