著者
Harumi Okuyama Naoki Ohara Kenjiro Tatematsu Shinya Fuma Tomoyuki Nonogaki Kazuyo Yamada Yuko Ichikawa Daisuke Miyazawa Yuko Yasui Seijiro Honma
出版者
The Japanese Society of Toxicology
雑誌
The Journal of Toxicological Sciences (ISSN:03881350)
巻号頁・発行日
vol.35, no.5, pp.743-747, 2010-10-01 (Released:2010-10-01)
参考文献数
25
被引用文献数
7 13 5

Canola and some other types of oil unusually shorten the survival of stroke-prone spontaneously hypertensive rats (SHRSP), compared with soybean oil, perilla oil and animal fats. Since differential effects of canola and soybean oil on steroid hormone metabolism were suggested by a preliminary DNA microarray analysis as a reason for this, the steroid hormone levels in the serum and tissues of SHRSP fed different oils were investigated. The testosterone levels in the serum and the testes were found to be significantly lower in the canola oil group than in the soybean oil group, while no significant differences were detected in the corticosterone and estradiol levels in tissues. In a second experiment, it was found that hydrogenated soybean oil, with a survival-shortening activity comparable to that of canola oil, also decreased the testosterone level in testes to a similar degree. The testosterone-lowering activity of canola and hydrogenated soybean oil observed in SHRSP was considered in relation to other factors possibly affecting the physiology of SHRSP.
著者
Mai Nishikawa Naoki Ohara Yukiko Naito Chihiro Amma Yoshiaki Saito Kenjiro Tatematsu Jinhua Baoyindugurong Daisuke Miyazawa Yoko Hashimoto Harumi Okuyama
出版者
The Japanese Society of Toxicology
雑誌
Fundamental Toxicological Sciences (ISSN:2189115X)
巻号頁・発行日
vol.9, no.1, pp.7-16, 2022 (Released:2022-01-15)
参考文献数
30

The present study was conducted to survey the influence of canola oil (CAN) ingestion on the steroid hormone production in stroke-prone spontaneously hypertensive rats (SHRSP). Male SHRSP were fed a diet containing 10 wt/wt% soybean oil (SOY, the control) or CAN as the sole dietary fat for 8 weeks. Plasma concentration of luteinizing hormone (LH) was similar in the 2 dietary groups. However, the plasma testosterone level in the CAN group, 1.36 ± 0.271 ng/mL, was lower than in the SOY group, 2.79 ± 0.514 ng/mL (p < 0.05, unpaired t-test; n = 10), and plasma concentration of aldosterone in the CAN group, 345 ± 79.6 pg/mL, was higher than in the SOY group, 159 ± 33.7 pg/mL (p < 0.05, unpaired t-test; n = 10). In the testis, the expressions of mRNA for StAR, CYP11A1, CYP17, 3βHSD and 17βHSD and the amounts of the corresponding proteins were significantly decreased. However, in the adrenal gland, the expressions of mRNA for StAR, CYP11A1, 3βHSD and CYP11B1 in the CAN group were not different from those in the SOY group, but the expression of mRNA and the amount of the corresponding protein for CYP11B2 were increased significantly in the CAN group. These findings are indicative of a peripheral, testicular toxicity of CAN. The decreased testosterone and the concomitantly increased aldosterone may play a role in the aggravation by CAN of the genetic diseases (i.e., metabolic syndrome-like complications) in male SHRSP.