| Background and Objectives:A variety of degenerative changes will appear in the body structure and function in the normal aging process of elderly people, such as increased metabolic disorders and the intestinal mucosa barrier damage. The protective effects of enteral nutrition treatment on acute intestinal mucosal barrier injury are obvious, but whether enteral nutrition have influence on the glucose and lipid metabolism in the elderly and age-related intestinal mucosal barrier dysfunction are lack of evidence. This study used different-month-old SD rats in order to (1) understand the influence of aging on the glucose and lipid metabolism in normal healthy SD rats; and the impact of enteral nutrition on glucose and lipid metabolism in elderly SD rats to evaluate the safety of enteral nutrition treatment in the elderly SD rats. (2) understand the influence of aging on the intestinal epithelial barrier in healthy aging SD rat; and whether the impact of enteral nutrition intervention on the change of intestinal mucosal barrier in eldly SD rats were protective.Materials and Methods:(1) Twenty 3-month-old SD rats were randomly divided into normal diet group(group A) and enteral nutrition plus normal diet group(group C). Twenty 12-month-old SD rats were randomly divided into normal diet group(group B) and enteral nutrition plus normal diet group(group D). Normal diet group were given regular feeding and water for a month.Enteral nutrition plus normal diet group were given regular feeding and water plus enteral nutrition (Peptisorb Liquid(?)) by intragastric administration, twice a day, lasted 1 month. Measure the rats' body weight in each group once every 10 days, assay the biochemical markers (include TG,TC,LDL-C,HDL-C,FBG,FINS,ALT,AST,ALB,TBIL) of rats in each group fed after a month, and calculate the insulin resistance index (HOMA-IR) through the HOMA model.(2) Twenty 3-month-old SD rats were randomly divided into normal diet group(group A) and enteral nutrition plus normal diet group(group C). Twenty 12-month-old SD rats were randomly divided into normal diet group(group B) and enteral nutrition plus normal diet group(group D). Normal diet group were given regular feeding and water for a month.Enteral nutrition plus normal diet group were given regular feeding and water plus enteral nutrition (Peptisorb Liquid(?)) by intragastric administration, twice a day, lasted 1 month. After fed a month, the liver, spleen, mesenteric lymph node tissue of rats in each group were taken for bacterial culture to calculate bacterial translocation rate. Morphological changes were measured in the rats'ileal tissue sealed in paraffin sections with routine H-E staining in each group. Using semi-quantitative revels transcription polymerase chain reaction (RT-PCR) analyzed the Occludin and ZO-1 mRNA expressions in the intestinal mucosa samples in each group. Using immuno-histochemistry techniques detected the Occludin and ZO-1 protein in the small intestinal tissue in each group.(3) Compare the difference of body weight, biochemical markers (include TG,TC LDL-C,HDL-C,FBG,FINS,ALT,AST,ALB,TBIL) and insulin resistance index (HOMA-IR) in 3-month-old normal diet group(group A) and 12-month-old normal diet group(group B),3-month-old enteral nutrition group(group C) and 12-month-old enteral nutrition group(group D),3-month-old normal diet group(group A) and 3-month-old enteral nutrition group(group C),12-month-old normal diet group(group B) and 12-month-old enteral nutrition group(group D).(4) Compare the difference of the Occludin and ZO-1 mRNA expressions in the intestinal mucosa samples, Occludin and ZO-1 protein in the small intestinal tissue and bacterial translocation rate in 3-month-old normal diet group(group A) and 12-month-old normal diet group(group B),3-month-old normal diet group(group A) and 3-month-old enteral nutrition group(group C),12-month-old normal diet group(group B) and 12-month-old enteral nutrition group(group D). Results:(1)After normal diet fed a month. compared to 3-month-old SD rats(group A). 12-month-old SD rats (group B) had the significantly lower body weight growth rate(P<0.05), higher levels of TG,TC,LDL-C,FINS,HOMA-IR and lower levels of HDL-C(P<0.05). After enteral nutrition plus normal diet fed a month, compared to 3-month-old SD rats(group C).12-month-old SD rats (group D) had the significantly lower body weight growth rate(P<0.05), higher levels of TG,TC,LDL-C,FINS,HOMA-IR and lower levels of HDL-C(P<0.05). After fed a month, Compared with 3-month-old rats in normal diet group(group A), 3-month-old rats in enteral nutrition plus normal diet group(group C) had more body weight gain(P<0.05), while the biochemical markers (include TG,TC,LDL-C,HDL-C,FBG,FINS,ALT,AST,ALB,TBIL) and HOMA-IR had no significant differences. After fed a month, Compared with 12-month-old rats in normal diet group(group B), 12-month-old rats in enteral nutrition plus normal diet group(group D) had more body weight gain(P<0.05), while the biochemical markers (include TG,TC,LDL-C,HDL-C,FBG,FINS,ALT,AST,ALB,TBIL) and HOMA-IR had no significant differences.(2)After normal diet fed a month, compared to 3-month-old SD rats(group A). 12-month-old SD rats (group B) had lower small intestinal thickness and villus height(P<0.05), less Occludin and ZO-1 mRNA expressions(P<0.05) and less Occludin and ZO-1 protein(P<0.05), while the bacterial translocation rate had no significant difference. After fed a month, Compared with 3-month-old rats in normal diet group(group A), 3-month-old rats in enteral nutrition plus normal diet group(group C) had no significant difference in the small intestinal thickness and villus height, Occludin and ZO-1 mRNA expressions, Occludin and ZO-1 protein, and bacterial translocation rate. After fed a month. Compared with 12-month-old rats in normal diet group(group B). 12-month-old rats in enteral nutrition plus normal diet group(group D) had higher small intestinal thickness and villus height, more Occludin and ZO-1 mRNA expressions(P<0.05), and more Occludin and ZO-1 protein(P<0.05). while the bacterial translocation rate had no significant difference.Conclusion:(1)Along with aging, compared with young SD rats, elderly SD rats own reduced growth rate in body weight, elevated TG,TC,LDL-C,FINS,HOMA-IR levels, and decreased HDL-C level, but had no significant difference in the other biochemical markers (FBG,ALT,AST,ALB,TBIL). After fed a month, Compared with normal diet fed young SD rats, enteral nutrition plus normal diet group fed eldly rats had more body weight gain, while the biochemical markers (include TG,TC,LDL-C,HDL-C,FBG,FINS,ALT,AST,ALB,TBIL) and HOMA-IR had no significant differences. Enteral nutrition ((Peptisorb Liquid(?)) have no significant influence on glucose and lipid metabolism in elderly SD rats, and can be safely used.(2) Along with aging, compared with young SD rats, elderly SD rats have lower small intestinal thickness and villus height, less Occludin and ZO-1 mRNA expressions, less Occludin and ZO-1 protein, and insignificant difference in bacterial translocation rate. After fed a month, Compared with normal diet fed young SD rats, enteral nutrition plus normal diet group fed eldly rats had higher small intestinal thickness and villus height, more Occludin and ZO-1 mRNA expressions, and more Occludin and ZO-1 protein. while the bacterial translocation rate had no significant difference. Enteral nutrition ((Peptisorb Liquid(?)) can improve the declined tight junction proteins(Occludin, ZO-1) of intestinal epithelial barrier in elderly SD rats, and produces a protective effect upon aging induced rat intestinal epithelial barrier injury. |
PDF Full Text Request