Effective prevention and control measures were needed urgently for children obesity

Obesity is a chronic metabolic disorder that the body fat accumulates excessively and damages the health. It can lead to various complications such as diabetes, cardiovascular diseases, hypertension and metabolic syndrome that damage the body health severely. In 2010, the death population due to overweight and obesity reached as high as 3.4 million and it was predicted that by 2025, this number would increase to 7.8 million [1]. With many factors changes like lifestyle, the morbidity of children obesity became higher and higher. In 2013, 23.8% male and 2.6% female of adolescents were obese or overweight in developed countries[2]. Based on the statistics, in 2010, the incidence of children obesity in our country increased nearly 50-fold compared with that of 1985, and it remained increasing [3]. Meta analysis proved that children with higher body mass index(BMI) had significant higher risk of cardiovascular diseases and metabolic disorders like hypertension, lipid metabolism disorder and insulin resistance[4]. Prospective cohort studies also pointed out that children obesity could last into adolescence and even adulthood [5-6]. Therefore, children obesity has become a key issue in the field of public health, thus we need to slow down effectively the rapid increase of children obesity and investigate the influential factors in order to make suitable prevention and control measures for the condition in our country.

 Intestinal flora maybe the new therapeutic target of children obesity

Obesity is co-regulated by the environment and gene.Besides diets and activities,although more and more researches showed that intestinal flora was closely associated with the incidence of obesity[7], the studies of intestinal flora spectrum and children obesity were rare. Given the current circumstances, most of the previous researches focused on bacteroidetes and firmicutes, which could not reflect the relation of intestinal flora and obesity comprehensively, but the conclusions were not consistent. Therefore,whether intestinal flora could influence the incidence of children obesity is still uncertain. As a result,further investigation of the influence of intestinal flora on children obesity will provide a new therapeutic target for the intervention and treatment of children obesity.

Short chain fatty acids may participate in the regulation of body fat accumulation

Currently, the influences of intestinal flora on the incidence of children obesity are controversial, but the regulation mechanism of intestinal flora on the fat accumulation is also unknown.However, more and more studies showed that short chain fatty acid (SCFA), the metabolite of intestinal flora may have played a crucial role in the fat accumulation regulation [8]. SCFA is product of dietary fiber metabolized by intestinal flora. They are branched chain fatty acids with2-4 carbon like acetic acid, propionic acid and but yric acid. Besides there sources of energy, SCFA can also play as signal molecule and regulate related pathways thus to influence the body metabolism. In addition, in vitro studies showed that acetic acid and propionic acid can decrease the fat accumulation [9], and the mice models showed injection of acetic acid can reduce the appetite [10],whereas, supplying mice the SCFA can inhibit the weight growth [11-12]. What’s more, Schwiertz et al. reported that, for people with BMI at an overweight and obesity level, the total SCFA in their feces was significantly higher than that in people with normal weight [13]. All of the studies suggested that intestinal flora may play a regulation role on the hosts’ fat accumulation by SCFA but no studies had investigated that whether the SCFA could influence the occurrence of children obesity and their role on the pathogenic chain of intestinal flora on the children obesity. Therefore,more studies were needed on whether intestinal could affect the SCFA level and further influence the children obesity.

In conclusion, exploration of the intestinal flora’s function on the children obesity and abundance of the theoretical knowledge like environmental risk factors and pathogenesis, will provide a new target for the early intervention and treatment practically from the perspective of intestinal flora.

References:

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[2]Ng, M., T. Fleming, M. Robinson, et al., Global,regional, and national prevalence of overweight and obesity in children and adults during 1980-2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet, 2014. 384(9945): p. 766-81.

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[9]Kimura, I., K. Ozawa, D. Inoue, et al., The gutmicrobiota suppresses insulin-mediated fat accumulation via the short-chain fatty acid receptor GPR43. Nat Commun, 2013. 4: p. 1829.

[10]Frost, G., M.L. Sleeth, M. Sahuri-Arisoylu, et al.,The short-chain fatty acid acetate reduces appetite via a central homeostaticmechanism. Nat Commun, 2014. 5: p. 3611.

[11]den Besten, G., A. Bleeker, A. Gerding, et al.,Short-Chain Fatty Acids protect against High-Fat Diet-Induced Obesity via aPPAR gamma-dependent switch from lipogenesis to fat oxidation. Diabetes, 2015.

[12]Lin, H.V., A. Frassetto, E.J. Kowalik, et al.,Butyrate and Propionate Protect against Diet-Induced Obesity and Regulate GutHormones via Free Fatty Acid Receptor 3-Independent Mechanisms. Plos One, 2012.7(4).

[13]Schwiertz, A., D. Taras, K. Schafer, et al.,Microbiota and SCFA in lean and overweight healthy subjects. Obesity (SilverSpring), 2010. 18(1): p. 190-5.