脂代谢与认知和长寿共有基因的遗传变异及分子机制研究

Base on lipid metabolism balance and longevity and cognitive-related genes in our group with the long-term researches, we hypothesize that there is a sharing core gene group which link traits to maintain the balance of lipid metabolism, then to promote the normal function of cognitive function in brain, thus to delay the foundation of aging in the body. In order to verify the original idea, we propose to filter out the false positive age of individuals according to Horvath clock correction, in contrast chronology years old, and obtain the true biological age of the subjects and group them firstly. Second, we choose 98 longevity related genetic variation loci of lipid metabolism balance regulatory genes as candidate target to study more than 8,000 longevity-control comparative genomics. Sharing gene variations of lipid metabolism and longevity and cognition can be identified by high-throughput sequencing. Third, we perform sharing gene mutations validation by leukocyte transcriptome and a level of serum lipid metabolism, cognitive function and longevity phenotype. Fourth, we use bioinformatics for functional prediction of sharing genes. Fifth, we explore the molecular mechanism of lipid metabolism and longevity and cognitive consensus gene mutations affecting lifespan by models in vivo and vitro. Finally, through detecting and comparing the physiological and biochemical evidences of longevity characteristics and the consensus gene mutations between longevity and age control group out of local natural aging individuals, we are going to preliminarily interpret the genetic and molecular mechanisms which lipid homeostasis can maintain normal cognitive function, in turn, delay aging by the comprehensive analysis of population, in vivo and vitro models, molecular level studies.

在本组长年进行的脂代谢平衡与长寿、认知相关基因研究基础上，提出假设:体内脂代谢平衡的维持，促进了认知功能的正常，从而延缓衰老的根基是存在有编码这一连锁性状的共有核心基因群。为检验该原创性思路，拟首先根据Horvath时钟检测，过滤掉假阳性年龄个体,得出研究对象的真实生物学年龄并分组。据此，以脂代谢平衡调节基因的98个长寿关联遗传变异位点为靶，进行长寿-对照的比较基因组学研究，经高通量测序分型识别共有基因变异；经白细胞转录组表达谱及血清脂代谢指标水平、认知功能和长寿表型进行共有基因变异验证；再经生物信息学对共有基因进行功能预测；并利用体内、外模型探索共有基因变异影响寿命的分子机制。通过检测和比较长寿和当地自然衰老个体获得共有基因变异与长寿特征关联的生理和生化证据，最终通过人群、体内、外模型和分子水平研究综合分析，初步解释脂代谢稳态维持正常认知功能进而延缓衰老的遗传和分子机制。

衰老是一个复杂的、多因素的过程，受到遗传和环境因素的影响。健康长寿个体被做为人类健康老龄的“典范”。本课题采用自制问卷收集对象人口学特征、家族疾病史等资料，通过体格检查测量对象的心率和血压，采集对象空腹外周静脉血，分别检测空腹血糖（FBG）、血浆总胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白胆固醇（HDL-C）、低密度脂蛋白胆固醇（LDL-C）、端粒长度、靶向基因测序和转录组测序，分析不同年龄段5个甲基化位点EDARADD cg09809672、IPO8 cg19722847、P2RX6 cg05442902、NHLRC1 cg22736354和SCGN cg06493994水平变化情况。结果：1）基于不同年龄段甲基化位点数据，应用多重线性回归法构建生物学年龄预测模型：Y=-53.121×EDARADD cg09809672-137.564×IPO8 cg19722847+141.040×NHLRC1 cg22736354-67.893×P2RX6 cg05442902+149.547×SCGN cg06493994+4.592×sex+64.185（R2=0.86，P<0.001），成功应用于研究对象的生物学年龄；2）从健康长寿人群的WES和GWAS数据中，识别健康长寿和脂代谢双表型关联的3个基因的6个变异位点：TFPI rs7586970（p=0.013, OR=1.100）、ADAMTS7 rs3825807（p=0.017, OR=1.198）和ABO rs8176719（p= 0.004, OR = 1.083），rs687621（p = 0.007, OR = 1.074），rs643434（p= 0.006, OR = 1.074），rs505922（p = 0.006, OR= 1.073），并初步分析其可能通过调节脂代谢促进健康长寿的分子机制；3）通过转录组学的测序数据，验证筛选和识别出的脂代谢、长寿和认知表型共有基因并进行功能预测，经长寿和对照组差异表达基因（DEGs）的GO注释和功能显著性分析，发现富集最多的分别在生物学过程中的单个组织过程、细胞过程、代谢过程和生物学调节。经长寿和对照组差异表达基因（DEGs）的KEGG 信号通路分类和功能富集分析，发现DEGs被显著富集到免疫系统、脂代谢和信号转导等通路中。总之，本课题所构建的表观遗传学时钟