title: Diet control to achieve euglycemia induces significant loss of heart and liver weight via increased autophagy compared with ad libitum diet in diabetic rats.
abstract: Intensive glucose control increases the all-cause mortality in type 2 diabetes mellitus (T2DM); however, the underlying mechanisms remain unclear. We hypothesized that strict diet control to achieve euglycemia in diabetes damages major organs, increasing the mortality risk. To evaluate effects on major organs when euglycemia is obtained by diet control, we generated a model of end-stage T2DM in 13-week-old Sprague-Dawley rats by subtotal pancreatectomy, followed by ad libitum feeding for 5 weeks. We divided these rats into two groups and for the subsequent 6 weeks provided ad libitum feeding to half (AL, n=12) and a calorie-controlled diet to the other half (R, n=12). To avoid hypoglycemia, the degree of calorie restriction in the R group was isocaloric (g per kg body weight per day) compared with a sham-operated control group (C, n=12). During the 6-week diet control period, AL rats ate three times more than rats in the C or R groups, developing hyperglycemia with renal hyperplasia. R group achieved euglycemia but lost overall body weight significantly compared with the C or AL group (49 or 22%, respectively), heart weight (39 or 23%, respectively) and liver weight (50 or 46%, respectively). Autophagy levels in the heart and liver were the highest in the R group (P<0.01), which also had the lowest pAkt/Akt levels among the groups (P<0.05 in the heart; P<0.01 in the liver). In conclusion, glycemic control achieved by diet control can prevent hyperglycemia-induced renal hyperplasia in diabetes but may be deleterious even at isocaloric rate when insulin is deficient because of significant loss of heart and liver mass via increased autophagy.
authors.affiliation: Department of Biochemistry, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Jun-Ho
authors.initials: JH
authors.lastname: Lee
authors.affiliation: 1] Department of Biochemistry, Konkuk University School of Medicine, Seoul, Republic of Korea [2] Rmedica-Stem Cell, Seoul, Republic of Korea.
authors.forename: Ju-Han
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Biochemistry, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Mingli
authors.initials: M
authors.lastname: Jin
authors.affiliation: Department of Neurology, Konkuk University School of Medicine, Chungju Hospital, Chungju, Republic of Korea.
authors.forename: Sang-Don
authors.initials: SD
authors.lastname: Han
authors.affiliation: Department of Pulmonary and Critical Care Medicine, Konkuk University School of Medicine, Chungju Hospital, Chungju, Republic of Korea.
authors.forename: Gyu-Rak
authors.initials: GR
authors.lastname: Chon
authors.affiliation: Department of Surgery, Konkuk University School of Medicine, Chungju Hospital, Chungju, Republic of Korea.
authors.forename: Ick-Hee
authors.initials: IH
authors.lastname: Kim
authors.affiliation: Department of Biochemistry, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Seonguk
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Biochemistry, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Sung-Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Konkuk University School of Medicine, Chungju Hospital, Chungju, Republic of Korea.
authors.forename: Soo-Bong
authors.initials: SB
authors.lastname: Choi
authors.affiliation: Department of Biochemistry, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Yun-Hee
authors.initials: YH
authors.lastname: Noh
mesh_terms: D000419:Albuminuria / Q000652:urine; D000818:Animals; D001343:Autophagy; D008076:Cholesterol, HDL / Q000097:blood; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000178:diet therapy* / Q000473:pathology* / Q000652:urine; D004032:Diet / Q000009:adverse effects*; D004435:Eating; D006029:Glycosuria / Q000652:urine; D007328:Insulin / Q000097:blood; D008099:Liver / Q000473:pathology*; D008297:Male; D009206:Myocardium / Q000473:pathology*; D009929:Organ Size; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D012709:Serum Albumin / Q000032:analysis
chemical_list: D008076:Cholesterol, HDL; D007328:Insulin; D012709:Serum Albumin; D051057:Proto-Oncogene Proteins c-akt