Analysis Of The M~6A-mRNA Status From Peripheral Blood Of Obese Patients With Short-term Low-carbohydrate Dietary Intervention

BackgroundObesity is a disease of abnormal fat or excessive deposition caused by a combination of genetic biology,social,environmental and other factors.According to the World Health Organization,as of 2016,the number of obesity in the world has exceeded 650 million,and the number of patients in China ranks first in the world,which has greatly increased the risk of type 2 diabetes,cardiovascular disease and various tumors,making obesity an urgent public health problem that seriously threatens human health.Medical nutrition intervention is recognized as the basic and key means of weight loss,and low-carbohydrate diet is currently the popular and effective dietary model.With the deepening of research,changes related to epigenetics have been found to be the possible internal mechanism by which the body responds to dietary changes and thus affects energy metabolism.Even though methylation modification has been a research hotspot in recent years,it mainly focuses on DNA methylation,and the methylation of mRNA,which also occupies an important position in the central law,is ignored,and even the information in this regard is blank.M6A methylation is the most abundant modification on mRNA,and it is closely involved in regulating its metabolism and translation,which in turn influences the life activities of cells.Several studies have confirmed that changes in environmental factors can lead to the dynamic remodeling of this methylation modification,which has great potential in regulating the occurrence and development of diseases.Therefore,excavating the changes in m6A methylation on mRNA in dietary pattern of low carbohydrate and their possible role in weight loss can help further reveal the potentially complex and multi-layered regulatory system of obesity,and provide new direction and strategy for the prevention and treatment of obesity.ObjectivesWe managed to verify the impact of short-term low-carbohydrate diet interventions on BMI,body fat rate,blood lipids,HOMA-IR and other indicators of obese people,and the dynamic changes of m6A methylation in peripheral circulation of obese patients before and after low-carbohydrate dietary intervention,so as to explore potential biological markers and the possible mechanism of its participation in weight loss under this dietary pattern.Methods1.The study recruited 3 obese or 3 healthy subjects who were BMI-,sex-and age-matched.Obese subjects received a 3-month low-carbohydrate diet intervention,and collected general information and biochemical indicators related to obesity before and after the intervention,and the mRNA was purified from the plasma of peripheral venous blood.While healthy subjects did not receive dietary intervention,and directly collected the clinical data and mRNA mentioned above.The retained mRNA was used for m6A methylation analysis.2.Used MeRIP-seq technology and biological information analysis platform to explore the m6A-mRNA spectrum characteristics of each group.Then we selected mRNAs whose degree of methylation was consistent with or opposite to the change trend of body weight,and were related to the energy metabolism pathway,and subsequently constructed their interaction protein network,performed Spearman Analyze to figure out their correlation with obesity-related indicators.Results1.Obese subjects showed a significant weight loss effect after receiving low-carbohydrate dietary intervention,and blood triglyceride levels also improved compared with before,and all had statistical significance.2.There was a change in m6A methylation profile of mRNA before and after dietary intervention.Compared with normal subjects,the m6A methylation degree of obese patients before dietary intervention was significantly lowered,but it increased after the intervention.Besides,the three groups had a common motif sequence(GGACU),which had been previously verified as the motif sequence of methyl transferase METTL14.3.The m6A methylation sites of the three groups were mainly enriched in the CDS region of mRNA,among which the group of obese subjects before intervention owned the highest concentration,while the group of obese subjects after intervention was slightly lower,and the lean group had the lowest.4.APLP2,UBE2D3,and ELF2 were the m6A-mRNAs whose degree of methylation was consistent with or opposite to the change in body weight,and related to energy metabolism.There is no protein interaction between the three,and their own interacting network protein enriched pathways had a certain relationship with glycolipid metabolism.5.Spearman correlation analysis showed that APLP2 was negatively correlated with BMI,body fat rate,fasting insulin,HOMA-IR,LDL,and triglycerides(all p<0.05),and positively correlated with HDL((r=0.731,p<0.05);UBE2D3 was negatively correlated with age,BMI,body fat rate,fasting insulin,HOMA-IR,total cholesterol,LDL,triglycerides(all p<0.05),and positively correlated with HDL(r=0.717,p<0.05);ELF2 was negatively correlated with age,BMI,body fat rate,fasting insulin,HOMA-IR,triglycerides(all p<0.05),and positively correlated with HDL(r=0.800,p<0.05).ConclusionsIn this study,a short-term low-carbohydrate dietary intervention was used to build a weight-loss model,combined with the emerging MeRIP-seq technology in the field of epigenetics,to explore the characteristics of m6A-mRNA changes in the peripheral blood of normal people and obese people before and after dietary intervention weight loss,and found APLP2,UBE2D3,and ELF2 may be biological markers for the development of obesity or participate in weight loss regulation under this dietary pattern.