Somabhai Chaudhari Archana, Raghuvanshi Ruma, Nareshkumar G
Department of Biochemistry, Faculty of Science, Maharaja Sayajirao University of Baroda, Vadodara-390002, India.
PLoS One. 2016 Oct 19;11(10):e0164860. doi: 10.1371/journal.pone.0164860. eCollection 2016.
To assess protective efficacy of genetically modified Escherichia coli Nissle 1917 (EcN) on metabolic effects induced by chronic consumption of dietary fructose.
EcN was genetically modified with fructose dehydrogenase (fdh) gene for conversion of fructose to 5-keto-D-fructose and mannitol-2-dehydrogenase (mtlK) gene for conversion to mannitol, a prebiotic. Charles foster rats weighing 150-200 g were fed with 20% fructose in drinking water for two months. Probiotic treatment of EcN (pqq), EcN (pqq-glf-mtlK), EcN (pqq-fdh) was given once per week 109 cells for two months. Furthermore, blood and liver parameters for oxidative stress, dyslipidemia and hyperglycemia were estimated. Fecal samples were collected to determine the production of short chain fatty acids and pyrroloquinoline quinone (PQQ) production.
EcN (pqq-glf-mtlK), EcN (pqq-fdh) transformants were confirmed by restriction digestion and functionality was checked by PQQ estimation and HPLC analysis. There was significant increase in body weight, serum glucose, liver injury markers, lipid profile in serum and liver, and decrease in antioxidant enzyme activity in high-fructose-fed rats. However the rats treated with EcN (pqq-glf-mtlK) and EcN (pqq-fdh) showed significant reduction in lipid peroxidation along with increase in serum and hepatic antioxidant enzyme activities. Restoration of liver injury marker enzymes was also seen. Increase in short chain fatty acids (SCFA) demonstrated the prebiotic effects of mannitol and gluconic acid.
Our study demonstrated the effectiveness of probiotic EcN producing PQQ and fructose metabolizing enzymes against the fructose induced hepatic steatosis suggesting that its potential for use in treating fructose induced metabolic syndrome.
评估基因工程改造的大肠杆菌Nissle 1917（EcN）对长期食用膳食果糖所诱导的代谢效应的保护作用。
EcN通过果糖脱氢酶（fdh）基因进行基因改造，以将果糖转化为5-酮-D-果糖；并通过甘露醇-2-脱氢酶（mtlK）基因进行改造，以将其转化为益生元甘露醇。体重150 - 200克的查尔斯·福斯特大鼠饮用含20%果糖的水两个月。每周一次给予EcN（pqq）、EcN（pqq-glf-mtlK）、EcN（pqq-fdh）益生菌处理，每次10⁹个细胞，持续两个月。此外，还评估了血液和肝脏中氧化应激、血脂异常和高血糖的参数。收集粪便样本以测定短链脂肪酸的产生及吡咯喹啉醌（PQQ）的产生。
通过限制性酶切鉴定EcN（pqq-glf-mtlK）、EcN（pqq-fdh）转化体，并通过PQQ测定和高效液相色谱分析检查其功能。高果糖喂养的大鼠体重、血清葡萄糖、肝脏损伤标志物、血清和肝脏脂质谱显著增加，抗氧化酶活性降低。然而，用EcN（pqq-glf-mtlK）和EcN（pqq-fdh）处理的大鼠脂质过氧化显著降低，同时血清和肝脏抗氧化酶活性增加。还观察到肝脏损伤标志物酶的恢复。短链脂肪酸（SCFA）增加证明了甘露醇和葡萄糖酸的益生元作用。
我们的研究证明了产生PQQ和果糖代谢酶的益生菌EcN对果糖诱导的肝脂肪变性有效，表明其在治疗果糖诱导的代谢综合征方面具有应用潜力。
