Comparison of mitochondrial and macrophage content between subcutaneous and visceral fat in db/db mice.
Central (visceral) obesity is more closely associated with insulin resistance, type 2 diabetes, and cardiovascular disease than peripheral (subcutaneous) obesity, however the underlying differences in morphology and pathophysiology between subcutaneous and visceral adipose are largely unknown. To evaluate the effects of diabetes and rosiglitazone (RSG) treatment, the expression of mitochondrial Hsp60, UCP-1 and F4/80 in inguinal subcutaneous (SC) fat, composed of white and brown adipose tissues, and epididymal (EP) fat, mainly white adipose tissue, were evaluated. In diabetic db/db mice, there was significant increased number of aggregated macrophage foci compared to db/+ mice, especially in EP fat. On the other hand, the expression of mitochondrial Hsp60 protein was suppressed in both SC and EP fat of db/db mice compared to db/+ mice, and the expression level of mitochondrial Hsp60 in db/+ mice was lower in EP fat compared with SC. In db/db mice, RSG suppressed the number of aggregated macrophage foci in EP fat, but not in SC fat. RSG ameliorated the mitochondrial Hsp60 expression and induced the expression of UCP-1 in both SC and EP fat. Taken together, these data suggest that differences exist in mitochondrial and macrophage content, and in the response to RSG between visceral and subcutaneous adipose tissue, and adipose type and distribution may be important for obesity-linked insulin resistance.
Okamoto
Yuji
Y
Development and Medical Affairs Division, GlaxoSmithKline, 4-6-15 Sendagaya, Shibuya-ku, Tokyo 151-8566, Japan.
Higashiyama
Hiroyuki
H
Rong
James X
JX
McVey
Matthew J
MJ
Kinoshita
Mine
M
Asano
Satoshi
S
Hansen
Michael K
MK
D017667:Adipocytes / Q000166:cytology / Q000187:drug effects; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D002452:Cell Count; D048430:Cell Shape; D048429:Cell Size; D018834:Chaperonin 60 / Q000378:metabolism; D003920:Diabetes Mellitus / Q000378:metabolism* / Q000473:pathology; D004195:Disease Models, Animal; D050152:Intra-Abdominal Fat / Q000378:metabolism* / Q000473:pathology; D007473:Ion Channels / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000378:metabolism*; D008297:Male; D051379:Mice; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism; D000077154:Rosiglitazone; D050151:Subcutaneous Fat / Q000378:metabolism* / Q000473:pathology; D045162:Thiazolidinediones / Q000494:pharmacology; D000071256:Uncoupling Protein 1
D001786:Blood Glucose; D018834:Chaperonin 60; D007473:Ion Channels; D024101:Mitochondrial Proteins; D045162:Thiazolidinediones; C000604372:Ucp1 protein, mouse; D000071256:Uncoupling Protein 1; D000077154:Rosiglitazone