Abdominal adiposity, insulin and bone quality in young male rats fed a high-fat diet containing soybean or canola oil.
OBJECTIVE
A low ratio of omega-6/omega-3 polyunsaturated fatty acids is associated with healthy bone properties. However, fatty diets can induce obesity. Our objective was to evaluate intra-abdominal adiposity, insulin, and bone growth in rats fed a high-fat diet containing low ratios of omega-6/omega-3 provided in canola oil.


METHODS
After weaning, rats were grouped and fed either a control diet (7S), a high-fat diet containing soybean oil (19S) or a high-fat diet of canola oil (19C) until they were 60 days old. Differences were considered to be significant if p<0.05.


RESULTS
After 60 days, the 19S and 19C groups showed more energy intake, body density growth and intraabdominal fat mass. However, the 19S group had a higher area (200%) and a lower number (44%) of adipocytes, while the 7S and 19C groups did not differ. The serum concentrations of glucose and insulin and the insulin resistance index were significantly increased in the 19C group (15%, 56%, and 78%, respectively) compared to the 7S group. Bone measurements of the 19S and 19C groups showed a higher femur mass (25%) and a higher lumbar vertebrae mass (11%) and length (5%). Computed tomography analysis revealed more radiodensity in the proximal femoral epiphysis and lumbar vertebrae of 19C group compared to the 7S and 19S groups.


CONCLUSIONS
Our results suggest that the amount and source of fat used in the diet after weaning increase body growth and fat depots and affect insulin resistance and, consequently, bone health.
Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brasil.
Carlos Alberto Soares da
CA
Costa
Aluana Santana
AS
Carlos
Aline de Sousa
Ade S
dos Santos
Alexandra Maria Vieira
AM
Monteiro
Egberto Gaspar de
EG
Moura
Celly Cristina Alves
CC
Nascimento-Saba
D050154:Adiposity / Q000502:physiology; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000502:physiology*; D059305:Diet, High-Fat / Q000009:adverse effects*; D002149:Energy Intake / Q000502:physiology; D005229:Fatty Acids, Monounsaturated / Q000009:adverse effects; D006128:Growth / Q000502:physiology*; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance / Q000502:physiology; D050152:Intra-Abdominal Fat / Q000378:metabolism / Q000502:physiology*; D008297:Male; D000074262:Rapeseed Oil; D051381:Rats; D017208:Rats, Wistar; D013024:Soybean Oil / Q000009:adverse effects; D013997:Time Factors; D014057:Tomography, X-Ray Computed
D001786:Blood Glucose; D005229:Fatty Acids, Monounsaturated; D007328:Insulin; D000074262:Rapeseed Oil; D013024:Soybean Oil