Human adipose tissue cannabinoid receptor 1 gene expression is not related to fat cell function or adiponectin level.
BACKGROUND
The cannabinoid receptor 1 gene (CNR1) is implicated in adipocyte function.


OBJECTIVE
We investigated human adipose tissue CNR1 mRNA in relation to obesity, clinical and metabolic variables, adipocyte function, and adiponectin (ADIPOQ) levels.


METHODS
We assessed sc fat biopsies from 96 obese and nonobese subjects and omental fat biopsies from 82 obese and nonobese subjects.


RESULTS
The sc and omental adipose CNR1 gene expression were similar in obese and nonobese subjects. No association between either sc or omental adipose CNR1 mRNA levels and body mass index, waist circumference, plasma levels of glucose and insulin, lipids, or blood pressure was found. The sc and omental maximal adrenergic lipolytic activation as well as lipolytic adrenoceptor sensitivity were not related to CNR1 gene expression. Lipogenesis in sc adipocytes also showed no association with CNR1 mRNA levels. Finally, no relation was found between adipose CNR1 gene expression and ADIPOQ mRNA, adipose tissue adiponectin secretion, or circulating adiponectin.


CONCLUSIONS
We found no association of human adipose tissue CNR1 mRNA expression with measures of body fat, metabolic parameters, fat cell function, or ADIPOQ expression. These data do not suggest a major role of human adipose CNR1 in fat cell function or metabolic disease development.
Löfgren
Patrik
P
Department of Medicine, Karolinska Institutet, M61, Karolinska University Hospital, 141 86 Stockholm, Sweden.
Sjölin
Eva
E
Wåhlen
Kerstin
K
Hoffstedt
Johan
J
D052242:Adiponectin / Q000235:genetics*; D000273:Adipose Tissue / Q000502:physiology*; D001706:Biopsy; D015992:Body Mass Index; D001835:Body Weight / Q000235:genetics; D015331:Cohort Studies; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008055:Lipids / Q000096:biosynthesis; D008066:Lipolysis; D008297:Male; D009765:Obesity / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D043884:Receptor, Cannabinoid, CB1 / Q000235:genetics*
D052242:Adiponectin; D008055:Lipids; D012333:RNA, Messenger; D043884:Receptor, Cannabinoid, CB1