title: On the site and mechanism of action of the anti-obesity effects of interleukin-6.
abstract: We conducted an experimental study examining the site and mechanism of action of the anti-obesity effect of interleukin-6 (IL-6) in mice and rats. We used dual energy X-ray absorptiometry (DEXA) and computerized tomography to investigate the body composition of mice with knockout of the IL-6 gene and wild-type control mice. Rats were treated with IL-6 or vehicle through intracerebroventricular (ICV) cannulae. Energy expenditure was measured as oxygen consumption by indirect calorimetry in metabolic chambers. Results showed that the mice lacking IL-6 increased in body weight compared with wild-type mice from 6 months of age onward, although there was no marked difference in food intake between the pre-obese IL-6 knockout mice and the wild-type mice. IL-6 given as a single ICV injection to rats stimulated oxygen consumption; whereas, the same doses were ineffective when given peripherally. Chronic ICV IL-6 treatment decreased body weight and fat mass in rodents. Administration of IL-6 may decrease fat mass in mice and rats by stimulating energy expenditure at the CNS level, possibly in the hypothalamus.
authors.affiliation: Division of Endocrinology, Sahlgrenska University Hospital, Gothenburg, Sweden. JOJ@medic.gu.se
authors.forename: John-Olov
authors.initials: JO
authors.lastname: Jansson
authors.forename: Kristina
authors.initials: K
authors.lastname: Wallenius
authors.forename: Ingrid
authors.initials: I
authors.lastname: Wernstedt
authors.forename: Claes
authors.initials: C
authors.lastname: Ohlsson
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Dickson
authors.forename: Ville
authors.initials: V
authors.lastname: Wallenius
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects; D000818:Animals; D019440:Anti-Obesity Agents / Q000494:pharmacology*; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D001921:Brain / Q000187:drug effects; D004734:Energy Metabolism / Q000187:drug effects; D007276:Injections, Intraventricular; D015850:Interleukin-6 / Q000494:pharmacology* / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D009765:Obesity / Q000188:drug therapy / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats
chemical_list: D019440:Anti-Obesity Agents; D001786:Blood Glucose; D015850:Interleukin-6