title: Changes in central and peripheral inflammatory responses to lipopolysaccharide in ovariectomized female rats.
abstract: Obesity leads to increases in inflammatory responses in a site-specific manner. Ovariectomized animals, usually used as menopause models, exhibit obesity; however, their inflammatory responses have not been fully examined. In the present study, we investigated whether ovariectomy had site-specific effects on inflammatory responses. First, fever and anorectic responses to systemic injections of lipopolysaccharide (LPS) (500μg/kg, i.p.) were compared between ovariectomized rats (OVX) and sham-operated female rats (Sham). Inflammatory cytokines at the central and peripheral levels were also compared under saline-injected and LPS-injected conditions. Body weight in OVX was significantly higher than in Sham. The anorectic responses (reduction of body weight and food intake) to LPS were higher in OVX than in Sham. In the hypothalamus, all of the examined cytokine (IL-1β, TNF-α and IL-6) mRNA levels in OVX were higher than in Sham under the LPS-injected condition. On the other hand, in serum and adipose tissue, only IL-6, not IL-1β and TNF-α, levels in OVX were significantly higher than those in Sham under the LPS-injected condition. Second, responses to central (intracerebroventricular) injections of LPS (500ng) were compared between OVX and Sham. The result was that the fever response in OVX was more evident than in Sham. Finally, responses to systemic injections of LPS (500μg/kg, i.p.) were compared between OVX (OVX-oil) and OVX with estradiol (E) and progesterone (P) supplementation (OVX-EP). The anorectic responses and hypothalamic cytokine mRNA levels under LPS-injected condition were not different between OVX-oil and OVX-EP. These results indicate that ovariectomy enhances inflammatory responses, especially at the central level compared with the peripheral level. As supplementation of E and P could not attenuate the anorectic and cytokine responses to LPS, the deficiency of gonadal steroids might not be directly involved in the increase of inflammatory responses in OVX.
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokushima Graduate School, Institute of Health Biosciences, 3-18-15 Kuramoto-Cho, Tokushima 770-8503, Japan. Electronic address: iwasa.takeshi@tokushima-u.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Iwasa
authors.forename: Toshiya
authors.initials: T
authors.lastname: Matsuzaki
authors.forename: Riyo
authors.initials: R
authors.lastname: Kinouchi
authors.forename: Ganbat
authors.initials: G
authors.lastname: Gereltsetseg
authors.forename: Masahiro
authors.initials: M
authors.lastname: Murakami
authors.forename: Munkhsaikhan
authors.initials: M
authors.lastname: Munkhzaya
authors.forename: Tungalagsuvd
authors.initials: T
authors.lastname: Altankhuu
authors.forename: Akira
authors.initials: A
authors.lastname: Kuwahara
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Yasui
authors.forename: Minoru
authors.initials: M
authors.lastname: Irahara
mesh_terms: D000273:Adipose Tissue / Q000276:immunology; D000818:Animals; D001835:Body Weight; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D007249:Inflammation / Q000276:immunology; D053583:Interleukin-1beta / Q000097:blood / Q000235:genetics / Q000276:immunology*; D015850:Interleukin-6 / Q000097:blood / Q000235:genetics / Q000276:immunology*; D020738:Leptin / Q000097:blood; D008070:Lipopolysaccharides / Q000276:immunology*; D009765:Obesity / Q000276:immunology*; D010052:Ovariectomy; D011374:Progesterone / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000235:genetics / Q000276:immunology*
chemical_list: C587672:IL1B protein, mouse; D053583:Interleukin-1beta; D015850:Interleukin-6; D020738:Leptin; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D011374:Progesterone; D004958:Estradiol
keywords: IL-1β; IL-6; Obesity; Ovariectomy; TNF-α