Effects On Number And Volume Of Fat Cells During Rats Growth By Swimming Exercise And/or High-Fat Diet

The number of overweight and obesity,which is resulted from sedentary lifestyleand high-fat or high-calorie diet,is increasing.Anatomically,obesity is characterized byan excessive adipose tissue mass,which will bring about increase in fat cells’ volumeand quantity.Therefore,obesity should be controlled by decreasing fat cells’ volumeand quantity.Fat cells’ volume is variable during the whole life.However,the growthfat cells’ quantity is occurred only before adult period which will achieve the peakpoint during the adolescence period and keep constant value during adult period.As aresult,it can be hypothesized that the peak value can be decreased by the exerciseintervention during the growth of peak quantity.Besides,the base of fat cells can bedecreased during adult period,which will play a positive effect on preventing theobesity.Purpose: The study was designed to observe the change of fat cells’ quantity andvolume during rats growth by swimming exercise and/or high-fat diet.Also,to explorethe impact on obesity during adult period.Methods: The study objects (SD,Sprague-Dawley) were randomly divided into fourgroups,Control Group with Ordinary Diet (C),Exercise Group with Ordinary Diet (E),High-fat Diet Group (H) and Exercise Group with High-fat Diet (HE).And the studywas assigned into three stages,4,8,12weeks.SD in Group E and Group HE exercisedby swimming (90min/d,3d/w),while there was no exercise in Group C and Group H.First,prepare fat tissue paraffin sections with HE staining.Second,measure thediameter of fat cells by IPP.Third,calculate the total quantity of fat cells.Results: As for the change of body weight and visceral fat weight in SD,the resultswere as follows.The body weight and visceral fat weight could be increased byhigh-fat diet.After4weeks,first,body weight in Group H was obviously higher thanthat in Group C(P＜0.05),Second,body weight and visceral fat weight in Group HEere obviously higher than that in Group E(P＜0.05).After4weeks,first,body weight and visceral fat weight in Group H were obviously higher than that in Group C(P＜0.05,P＜0.01).Second,visceral fat weight in Group HE was obviously higher than thatin Group E(P＜0.05).And the growth of body weight and visceral fat weight could beweakened by swimming exercise.First,after8weeks,body weight and visceral fatweight in Group E were obviously lower than that in Group C(P＜0.05).Second,after12weeks,body weight and visceral fat weight in Group E were obviously lower thanthat in Group C(P＜0.05,P＜0.01)and body weight and visceral fat weight in GroupHE were obviously lower than that in Group H(P＜0.05,P＜0.01).As for the volume change of visceral fat cells in SD,the results were as follows.The volume of fat cells could be increased by high-fat diet.First,after4weeks,visceralfat cells in Group H was obviously higher than that in Group C(P＜0.05)and so wasafter8weeks.Second,after12weeks,visceral fat cells in Group HE was obviouslyhigher than that in Group E(P＜0.05).And the volume of fat cells could be decreasedby swimming exercise.First,after4weeks,volume of fat cells in Group HE wasobviously lower than that in Group H(P＜0.05).Second,after12weeks,volume of fatcells in Group E was obviously lower than that in Group C(P＜0.05)and volume of fatcells in Group HE was obviously lower than that in Group H,but there was nosignificant difference between the two groups(P＜0.01,P＜0.05).As for the quantity change of visceral fat cells in SD,the results were as follows.The quantity change of visceral fat cells could be increased by high-fat diet.First,after8weeks,the quantity of visceral fat cells in Group HE was obviously higher than thatin Group E(P＜0.05).Second,after12weeks,the quantity of visceral fat cells in GroupH was obviously higher than that in Group C(P＜0.05).And the quantity of fat cellscould be decreased by swimming exercise.First,after8weeks,quantity of fat cells inGroup E was obviously lower than that in Group C(P＜0.05).Second,after12weeks,quantity of fat cells in Group HE was obviously lower than that in Group H(P＜0.05).Conclusion: The peak value of fat cells could be increased by high-fat diet during thegrowth period.Beside,high-fat diet with swimming exercise could be inhibited tosome extent.However,there was no significant influence on the quantity of fat cells in SD with ordinary diet by swimming exercise.