Paper intensive reading (五)：A Review on Role of Microbiome in Obesity and Antiobesity Properties
论文题目：A Review on Role of Microbiome in Obesity and Antiobesity Properties of Probiotic Supplements
Published 9 May 2019
Bhagavathi Sundaram Sivamaruthi, Periyanaina Kesika, Natarajan Suganthy, and Chaiyavat Chaiyasut
Chiang Mai University
Published in BioMed Research International
Google citation: 4
Abstract:
Probiotics are now recognized for several health benefits and they have been recommended as a complementary therapeutic agent for metabolic disorders. Obesity is an altered health condition, which is a resultant of irregular energy intake and energy balance, changes in gut microbiota, and improper diet with the influence of genetic makeup and environmental factors(肥胖是肠道菌群变化的结果？). Several studies revealed the influence of probiotic suuplementation on obesity-associated consequences in vitro, in vivo, and in human clinical studies. The current manuscript discussed the factors influencing the occurrence of obesity, the interplay between microbiome and obesity, the effect of the probiotic intervention on the health status of obese people, and possible mechanism of antibesity activity of probiotics. The literature survey revealed that the antiobese activity of probiotics might be associated with their ability to alter the intestinal microbiota, remodeling of energy metabolism, alter the expression of genes related to thermogenesis(生热作用), glucose metabolism, and lipid metabolism(脂质代谢), and change the parasympathetic(副交感神经系统) nerve activity. Further intense research is necessary to figure out the best probiotic or synbiotic mixture and optimum dosage and the duration of the intervention to reduce obesity and prevent the recurring of obese condition.
Outline:
1. Introduction
2. Obesity: Influencing Factors and Consequences
3. Microbiome
3.1 Development and Composition of Gut Microbiota 肠道菌群的发育和组成
3.2 Host-Gut Microbiota Metabolite Interaction 宿主-肠道菌群代谢物相互作用
3.3 Gut Microbiota and Obesity 肠道菌群与肥胖
4. Influence of Probiotic Supplementation on Health Status of Obese People 益生菌补充剂对肥胖人群的健康状况的影响
5. In Vivo Studies Using Laboratory Animal Models 使用实验动物模型进行体内研究
6. Conclusion and Future Perspectives
Content:
1. Introduction
GM is involved in the energy balancing, intestinal integrity, and immunity against invading pathogens; thereby GM controls the overall health status of the host. 这个结论是业界公认的吗？
GM can be positively altered by the supplementation of probiotics, a group of beneficial microbes that confers health benefits when consumed in an adequate amount. 补充益生菌有益健康，在很多疾病上有研究表明
Obesity is an altered health condition, which is a resultant of irregular energy intake and energy balance, changes in GM, and improper diet with the influence of genetic makeup and environmental factors. 肠道菌群变化是肥胖的原因？
The overweight with some ill-health conditions such as diabetes, hypertension, and cardiovascular diseases is considered as morbid obesity. 还有很多病变性肥胖
GM is one of the influencing environmental factors involved in the initiation of obesity mainly by disturbing the food intake and energy balance. 肠道菌群在肥胖方面的影响主要是干扰食物摄入和能量平衡
The published scientific documents have been searched and retrieved from Scopus, Web of Science, PubMed, and Google Scholar using the search terms “Probiotic” and “obesity.” 这篇review的文献查找方法，其实这些工作是不是现在可以用Python写？如果后续有时间的话，可以尝试一下，或者我觉得应该有已经写好的工具，因为区别就在于关键词嘛
2. Obesity: Influencing Factors and Consequences
Several factors are associated with the development of obesity. 各种因素啊
3. Microbiome
Each individual has unique GM composition influenced by several endogenous and exogenous factors such as gestational age, mode of delivery, breastfeeding, antibiotic exposure, diet, and lifestyle. 肠道菌群的个性化
The colonization of GM is not uniform throughout the gastrointestinal tract(胃肠道) with limited distribution in stomach and small intestine(小肠) followed by a dense and diverse population in the colon(结肠) due to the absence of digestive secretion, slow peristalsis(蠕动), and rich nutrient supply. 肠道菌群分布的部位，结肠处最密集
recent scientific investigations have shown that GM has emerged as a prime endogenous factor influencing obesity. 近期研究表明，肠道菌群是肥胖症的主要内源性因素。
3.1 Development and Composition of Gut Microbiota
In the first year of child life, the microbial composition varies according to developmental changes, host genotype, and food intake, which stabilizes similar to adult microbiota by the age of 3 years. 之前不是一个文献说2.5岁趋于稳定？
. In healthy adult individuals, the microbiota of the gut is in a symbiotic relationship with the host, which depends on host lifestyle, diet, and antibiotics, while in elderly people the composition of microbiota changes depending upon the alteration in digestive physiology and diet. 健康的成年人的肠道菌群决定因素，跟老年人的还有点区别
GM belongs to the phyla Bacteroidetes, Firmicutes, Actinobacteria, Proteobacteria, and Verrucomicrobia among which, Bacteroidetes and Firmicutes account for 90% of the total bacterial species [82]这个之前的文献上有图的
Healthy human GM is characterized by a high ratio of Bacteroidetes to Firmicutes, while in obese individuals inverse ratio is observed with a high prevalence of Firmicutes [85] 这篇文献里面肯定仔细研究了健康人群的肠道菌群分布
These data strongly link that certain bacterial phyla/class/species colonized in the gut acts as a driving force leading to the onset of obesity.
3.2 Host-Gut Microbiota Metabolite Interaction
Mounting evidence revealed that metabolites derived by fermentation of food by GM play a vital role in regulating the host metabolism with perspective to obesity. 发酵食品
增加饱腹感，减少食欲
SCF derived from GM regulates host metabolism by interaction with complex metabolic pathways intertwined with the nervous, endocrine, and immune system.
In healthy individuals SCF modulates the gut integrity, gut hormone production, and immune function, while in diseased state SCF exhibits a protective effect against diabetes, ulcerative colitis, colorectal cancer, and neurodegenerative disorders 健康个体，疾病个体
Understanding the mechanism of interaction of SCFs with its receptor will help in exploring the therapeutic way for the treatment of obesity and health-related disorders.
3.3 Gut Microbiota and Obesity
GM leads to host obesity through various routes such as by altering the intestinal permeability(渗透性) leading to endotoxemia(肉毒素血症), enhanced calorie provision, and endocannabinoid system (eCB,内源性大麻素系统) stimulation and by regulating the lipid metabolism(脂质代谢) by enhancing lipoprotein lipase(脂肪酶) activity and lipogenesis(脂肪生成)
endocannabinoid system (eCB,内源性大麻素系统) 很多文献都简称ECS啊？？？？
the role of SCF in obesity a puzzle 相关研究的结果有冲突之处
Overall the studies reveal that GM activates the eCB system, which increases intestinal permeability promoting LPS migration into the circulatory system causing endotoxemia. Increased LPS, in turn, alters the tight junction integrity of the intestinal membrane enhancing increased release of LPS into circulation creating virtuous circle promoting adipogenesis.
The gut microbiome is a complex microbial world having both beneficial and harmful microbes and manipulation of these microbes for the therapeutic purpose is possible only if the precise role of each and every individual microbe is known.
GM, its metabolite, and host are interplaying systems; therefore integration of this system will give us a comprehensive idea of the function of each building block of this system [117, 118]. 系统集成
4. Influence of Probiotic Supplementation on Health Status of Obese People
Table 1: Influence of probiotic supplementation on obese people.
包含了25个study，总结在excel表格中，并且每个study进行了描述，但是目前我还没有看出这些study组织的逻辑。我觉得作者这种排序方式一定有他的道理。以及一些study如何取做比对。
5. In Vivo Studies Using Laboratory Animal Models
Table 2: Effects of probiotic supplementation on obese-experimental animal model. 6个study
6. Conclusion and Future Perspectives
The detailed literature survey showed that the beneficial impact of probiotic supplementation in obese people has been associated with several factors such as nature of the probiotic strain, composition of the probiotic formula (single or multistrain; with or without prebiotics), duration of the intervention, dose, and other aided activities like calorie/dietary restrictions and weight loss medications. 详细的文献调查显示，补充益生菌对肥胖人群的有益影响与多种因素有关，例如益生菌菌株的性质，益生菌配方的组成（单菌株或多菌株；有或没有益生元），干预时间， 剂量以及其他辅助活动，例如卡路里/饮食限制和减肥药。
有一项研究表明肥胖与益生菌补充无关，可能是因为选择的文献数量过少。120显示有作用并且多菌株与单菌株相比，至少需要干预8周；121显示，干预3到12周，可以显著降低体重
Most importantly probiotic intervention greatly modified the composition of intestinal microbiota 益生菌可以干预肠道菌群组成
increased the load of Bifidobacterium(双歧杆菌), Lactobacillus(乳酸菌), Proteobacteria(变形菌门), Bacteroidetes(拟杆菌门), and Peptococcaceae(消化球菌科) members and reduced the amount of Firmicutes(厚壁菌门), Clostridium(梭菌属), and Actinobacteria(放线菌)
To conclude, as GM plays a key role in host metabolism, modulation of its composition represents a promising strategy for the treatment of obesity.
Further studies are necessary to evaluate the best combination of probiotic strains or synbiotic preparation to extend the health benefits of probiotics in obese individuals. 益生菌菌株或合生元的结合来延伸益生菌对肥胖者的健康益处