Influence of dietary fatty acids composition, level of dietary fat and feeding period on some parameters of androgen metabolism in male rats.
The aim of the present study was to determine the effect of the composition of dietary fatty acids, the duration of feeding period and dietary fat level on androgen metabolism in male rats. One hundred and twelve Wistar rats were divided into 18 groups which were fed three diets containing different types of fat (rapeseed [R], palm [P] and fish [F] oil) at either normal fat level (w/w; 5%) or high fat level (20%) during one, three or six weeks. Blood plasma level of androgen (testosterone+dihydrotestosterone) and testicular activity of 17beta-hydroxysteroid dehydrogenase (17beta-HSD) were investigated. In addition, androgen content in cytosol of the heart, the target organ, was measured. Androgen concentration in both blood plasma and heart cytosol extracts was measured by radioimmunoassay. The activity of 17Beta-HSD was expressed as a conversion of [3H]androstendione to [3H]testosterone in soluble fraction of gonadal homogenates. Plasma androgen concentration was influenced by a type of dietary fat (p<0.05). The highest plasma level of androgen was observed in animals fed R diets rich in unsaturated fatty acids. Significantly lower androgen concentration was demonstrated in rats fed P diets rich in saturated fatty acids. Only the feeding period factor significantly influenced androgen content in cytosol fraction of heart muscle cells (p<0.01). A positive correlation was found between plasma androgen concentration in plasma and cytosol fraction of the heart muscle cells (r=0.63, p<0.001). The feeding period (p<0.001) and dietary fat type (p<0.05) significantly affected the activity of 17beta-HSD. The least 17beta-HSD activity was observed in animals consuming the P-20% diet for six weeks. In summary, dietary fat type and feeding period, but not fat level, significantly affected both testosterone production and testosterone uptake by the target organ in male rats. It was found that a rapeseed diet rich in unsaturated fatty acids stimulated the testicular function in rats.
Gromadzka-Ostrowska
Joanna
J
Department of Dietetics and Functional Foods, Faculty of Human Nutrition and Consumer Sciences, Warsaw Agricultural University, Warsaw, Poland. gromadzka@alpha.sggw.waw.pl
Przepiórka
Magdalena
M
Romanowicz
Katarzyna
K
D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D000728:Androgens / Q000096:biosynthesis* / Q000097:blood; D000818:Animals; D001835:Body Weight / Q000187:drug effects*; D004041:Dietary Fats / Q000378:metabolism / Q000494:pharmacology*; D005229:Fatty Acids, Monounsaturated; D005395:Fish Oils / Q000494:pharmacology; D008297:Male; D009206:Myocardium / Q000737:chemistry; D000073878:Palm Oil; D010938:Plant Oils / Q000494:pharmacology; D011863:Radioimmunoassay; D000074262:Rapeseed Oil; D051381:Rats / Q000378:metabolism* / Q000502:physiology*; D017208:Rats, Wistar; D013737:Testis / Q000737:chemistry
D000728:Androgens; D004041:Dietary Fats; D005229:Fatty Acids, Monounsaturated; D005395:Fish Oils; D010938:Plant Oils; D000074262:Rapeseed Oil; D000073878:Palm Oil; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase