title: Fish oil consumption prevents glucose intolerance and hypercorticosteronemy in footshock-stressed rats.
abstract: BACKGROUND
  Environmental stress plays an important role in the development of glucose intolerance influencing lipid and glucose metabolism through sympathetic nervous system, cytokines and hormones such as glucocorticoids, catecholamines and glucagon. Otherwise, fish oil prevents glucose intolerance and insulin resistance. Although the mechanisms involved are not fully understood, it is known that sympathetic and HPA responses are blunted and catecholamines and glucocorticoids concentrations can be modulated by fish consumption. The aim of the present study was to evaluate whether fish oil, on a normal lipidic diet: 1) could prevent the effect of footshock-stress on the development of glucose intolerance; 2) modified adiponectin receptor and serum concentration; and 3) also modified TNF-α, IL-6 and interleukin-10 (IL-10) levels in adipose tissue and liver. The study was performed in thirty day-old male Wistar randomly assigned into four groups: no stressed (C) and stressed (CS) rats fed with control diet, and no stressed (F) and stressed (FS) rats fed with a fish oil rich diet. The stress was performed as a three daily footshock stress sessions.
  
  
  RESULTS
  Body weight, carcass fat and protein content were not different among groups. FS presented a reduction on the relative weight of RET. Basal serum glucose levels were higher in CS and FS but 15 min after glucose load just CS remained with higher levels than other groups. Serum corticosterone concentration was increased in CS, this effect was inhibited in FS. However, 15 min after footshock-stress, corticosterone levels were similar among groups. IL-6 was increased in EPI of CS but fish oil consumption prevented IL-6 increase in FS. Similar levels of TNF-α and IL-10 in RET, EPI, and liver were observed among groups. Adipo R1 protein concentration was not different among groups. Footshock-stress did not modify AdipoR2 concentration, but fish oil diet increases AdipoR2 protein concentration.
  
  
  CONCLUSIONS
  Footshock-stress promotes glucose intolerance associated to corticosterone serum level and epididymal white adipose tissue IL-6 concentration increase. The fish oil consumption by stressed rats normalized the stress responses. These results suggested that fish oil intake could be useful to minimize or prevent the development of diseases associated to the stress.
authors.affiliation: Departamento de Fisiologia, Universidade de São Paulo - UNIFESP - Rua Botucatu, 862, 2nd floor, Edifício de Ciências Biomédicas, Vila Clementino, São Paulo, SP, Brazil.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Eguchi
authors.forename: Flavia R
authors.initials: FR
authors.lastname: Scarmagnani
authors.forename: Claudio A
authors.initials: CA
authors.lastname: Cunha
authors.forename: Gabriel I H
authors.initials: GI
authors.lastname: Souza
authors.forename: Luciana P
authors.initials: LP
authors.lastname: Pisani
authors.forename: Eliane B
authors.initials: EB
authors.lastname: Ribeiro
authors.forename: Claudia M
authors.initials: CM
authors.lastname: Oller do Nascimento
authors.forename: Regina C
authors.initials: RC
authors.lastname: Spadari-Bratfisch
authors.forename: Lila M
authors.initials: LM
authors.lastname: Oyama
mesh_terms: D052242:Adiponectin / Q000097:blood; D000818:Animals; D019540:Area Under Curve; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000187:drug effects; D003345:Corticosterone / Q000097:blood*; D016207:Cytokines / Q000378:metabolism; D004597:Electroshock; D005247:Feeding Behavior / Q000187:drug effects*; D005395:Fish Oils / Q000008:administration & dosage* / Q000494:pharmacology*; D018149:Glucose Intolerance / Q000097:blood / Q000517:prevention & control*; D007328:Insulin / Q000097:blood; D008297:Male; D009928:Organ Specificity / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D054419:Receptors, Adiponectin / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: D052242:Adiponectin; D001786:Blood Glucose; D016207:Cytokines; D005395:Fish Oils; D007328:Insulin; D054419:Receptors, Adiponectin; C504339:adiponectin receptor 1, rat; C506573:adiponectin receptor 2, rat; D003345:Corticosterone