The aging gut and the role of prebiotics,probiotics, and synbiotics: A review

The United States (US) Census Bureau estimates the current US population at 301 million with elderly people (>65 years old) accounting for 36 million. Within this group, the fastest growing segment of the population is >85 years of age, which currently numbers ∼5 million and is expected to rise to ∼20 million by 2050. Over the decades there has been speculation that gastrointestinal structure and function decline with age. Therefore, the physiological changes in the gut with aging and their clinical implications have become important topics for discussion. This review also attempts to document the role of probiotics in enhancing gut activity in older persons.     

Gut microbiota role in irritable bowel syndrome: New therapeutic strategies

In the last decade the impressive expansion of our knowledge of the vast microbial community that resides in the human intestine, the gut microbiota, has provided support to the concept that a disturbed intestinal ecology might promote development and maintenance of symptoms in irritable bowel syndrome(IBS). As a correlate, manipulation of gut microbiota represents a new strategy for the treatment of this multifactorial disease. A number of attempts have been made to modulate the gut bacterial composition, following the idea that expansion of bacterial species considered as beneficial(Lactobacilli and Bifidobacteria) associated with the reduction of those considered harmful(Clostridium, Escherichia coli, Salmonella, Shigella and Pseudomonas) should attenuate IBS symptoms. In this conceptual framework, probiotics appear an attractive option in terms of both efficacy and safety, while prebiotics, synbiotics and antibiotics still need confirmation. Fecal transplant is an old treatment translated from the cure of intestinal infective pathologies that has recently gained a new life as therapeutic option for those patients with a disturbed gut ecosystem, but data on IBS are scanty and randomized, placebo-controlled studies are required.     

Gut dysbiosis and irritable bowel syndrome: The potential role of probiotics

Objective

To discuss the role of gut dysbiosis in the development of irritable bowel syndrome (IBS) and the impact of probiotics as a potential therapeutic measure.

Gut microbiome: Linking together obesity,bariatric surgery and associated clinical outcomes under a single focus

Obesity is increasingly prevalent in the post-industrial era, with increased mortality rates. The gut microbiota has a central role in immunological, nutritional and metabolism mediated functions, and due to its multiplexity, it is considered an independent organ. Modern high-throughput sequencing techniques have allowed phylogenetic exploration and quantitative analyses of gut microbiome and improved our current understanding of the gut microbiota in health and disease. Its role in obesity and its changes following bariatric surgery have been highlighted in several studies. According to current literature, obesity is linked to a particular microbiota profile that grants the host an augmented potential for calorie release, while limited diversity of gut microbiome has also been observed. Moreover, bariatric surgery procedures represent effective interventions for sustained weight loss and restore a healthier microbiota, contributing to the observed fat mass reduction and lean mass increase. However, newer evidence has shown that gut microbiota is only partially recovered following bariatric surgery. Moreover, several targets including FGF15/19 (a gut-derived peptide), could be responsible for the favorable metabolic changes of bariatric surgery. More randomized controlled trials and larger prospective studies that include well-defined cohorts are required to better identify associations between gut microbiota, obesity, and bariatric surgery.     

大鼠过氧化体增殖物激活型受体α在衰老过程中表达差异及与脂质代谢的关系

观察过氧化体增殖物激活型受体α在衰老过程中表达差异，在分子水平上探讨衰老过程中出现脂质代谢异常的可能机制。选用SD年轻大鼠(6-8周龄)和老年大鼠(24月龄)，测定血清甘油三酯和总胆固醇水平，采用逆转录-聚合酶链反应检测大鼠肝脏过氧化体增殖物激活型受体α及其目标基因mRNA水平，用Westem印迹法检测过氧化体增殖物激活型受体蛋白的表达。结果发现，与年轻鼠组比较，老年鼠组血清甘油三酯和总胆固醇水平升高，过氧化体增殖物激活型受体αmRNA及蛋白表达随年龄增长而减少，目标基因的表达也受年龄的影响。结果提示，衰老过程中过氧化体增殖物激活型受体α表达减少可能与老年脂质代谢异常有关。