Hippocampus Development Impairment And Transcriptomic Profile Of Offspring After Maternal Fructose Exposure During Gestation And Lactation

Background: With the society development,people’s living environment and dietary structure have undergone great changes,and the fructose intake has also increased.The risk of maternal high-fructose diet was also progressively increased in this dietary environment,maternal excessive fructose intake during gestation and lactation is an important public health issue.Gestation and lactation are critical periods for the offspring’s early development,especially the formation and development of the nervous system.The hippocampus is also an important nerve center that regulates the learning and memory.Many studies have shown that the maternal diet during gestation and lactation was closely affects the offspring’s growth,and the maternal high-fructose diet can have adverse effects on various physiological functions.However,the impact of hippocampus development and its molecular mechanism are poorly explored.Methods: The rat model of high-fructose diet during gestation and lactation was established by 13% and 40% fructose drinking water.Mating was carried out after a week of adaptive feeding.The vaginal suppository was the criterion for determining gestation,and the day of discovery was the Gestation Day(GD)0.The dams were randomly divided into control group(Con),13% fructose group,and 40% fructose group on the GD0 and began to drink water corresponding to the fructose concentration.The offspring were separated on the Postnatal Day(PND)21 and raised separately by sex,then started normally diet until PND60.The 12 hrs fasting blood glucose(FBG)values of offspring were detected at PND21 and PND60 to determine the validity of the animal model.The offspring’s neurobehavioral changes were observed by the Mirror water maze(MWM)test and open field test.Oxford Nanopore Technologies(ONT)full-length transcriptome sequencing was used to detect differentially expressed transcripts(DETs)and genes,differentially spliced genes(DSGs),and long no-coding RNA(lncRNA)in the hippocampus of PND60 offspring;Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis were performed to explore the changed biological functions.Based on the results of enrichment analysis,the expression changes of proteins and genes were explored with molecular experiments.The SPSS21.0 was used for statistical analysis,and the difference was statistically significant when P<0.05.Results: 1.FBG statistics showed that whether PND21 or PND60,the results of fructose groups were significantly higher than Con group,and the 40% fructose group was also significantly higher than 13% fructose,these differences were statistically significant(P<0.05).2.In the MWM test,the platform latency of the two fructose groups were longer than the Con group in each training day and was significant longer on the last test day(P<0.05);on the last training day,the time spent in the platform located quadrant(%)of two fructose groups were significantly lower than Con group,and the difference was statistically significant(P<0.05).3.In the open field test,the frequency of central region,active time,anxiety time,and grooming number in the two fructose groups were significantly longer than those in the Con group(P<0.05);The trajectories of the offspring rats in the two fructose groups were more disordered than in the Con group.4.ONT full-length transcript sequencing identified 369 DETs,298 DSGs,and 51 differentially expressed alternative spliced(DEAS)genes in the Con and 13% fructose groups.In the control group and 40% fructose group,501 DETs,313 DSGs,and 74 DEAS genes were identified.A total of 882 lncRNAs were identified.5.The enrichment analysis of GO and KEGG pathways highlighted several inspiring items and pathways,including some related to brain tissue development,learning and memory;interaction network analysis was used to reveal the relationship between physiological functions.6.Fluoro-jade C staining showed that the degenerated neurons in the hippocampus of the two fructose groups were obvious more than that of the Con group.The immunofluorescence staining showed that the expression of axonal structural proteins in the hippocampus of the two fructose groups was obvious lower than that of the Con group.7.Western blotting results showed that the expressions of GSK-3β and p-β-catenin in the two fructose groups were higher than those in the Con group;Wnt3a,p-GSK-3β and β-catenin were lower than those in the Con group(P<0.05).The expression of synaptic proteins in the two fructose groups was lower than that in the Con group(P<0.05).The expression of dopamine receptor protein in two fructose groups was higher than that in the Con group(P<0.05).Conclusions: 1.Maternal high-fructose diet during gestation and lactation adverse effects the learning and memory function of offspring by changing the expression of hippocampal transcripts.2.Maternal high-fructose diet during gestation and lactation affects synaptic development of offspring hippocampus by altering pre-m RNA editing process in offspring hippocampus.3.Maternal high-fructose diet during gestation and lactation affects offspring anxiety-like behaviors by changing the regulation process of target genes by hippocampal lncRNAs.