Subcutaneously administrated genistein and daidzein decrease serum cholesterol and increase triglyceride levels in male middle-aged rats.
Nutritional supplements containing soybean phytoestrogens, the isoflavones genistein (G) and daidzein (D), are increasingly used as alternative therapy for osteoporosis, cancer, and cardiovascular and other diseases with a frequency that increases with advancing age. In this study we examined the effects of subcutaneous administration of either G or D on serum lipid levels in orchidectomized (Orx) and intact (IA) middle-aged male rats, which are experimental models of andropause. Sixteen-month-old Wistar rats were treated with 10 mg/kg and 30 mg/kg of either G or D. The control groups received testosterone, estradiol, or vehicle for 3 weeks, after which the total serum cholesterol (TC), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), and total triglycerides (TT) were measured. Compared with the matching vehicle-treated controls, the higher doses of G and D and testosterone treatment significantly (P < 0.05) lowered the TC and lipoprotein cholesterol levels. The greatest effect was observed regarding LDL-C in both Orx and IA males after G and D treatments, in which LDL-C decreased by more than 30%. The lower isoflavone doses induced a significant cholesterol-lowering effect (P < 0.05) only in the Orx group. Like the estradiol treatment, the higher doses of G and D increased the TT levels in both rat models by more than 50% (P < 0.05). The lower doses of isoflavones increased TT only in the Orx group. In male middle-aged rats, injections of higher doses of G and D decreased the serum cholesterol levels, as did testosterone injection, and brought about an increase in serum triglycerides similar to that observed after estradiol treatment.
Sosić-Jurjević
Branka
B
Institute for Biological Research, Belgrade, Serbia. brankica@ibiss.bg.ac.yu
Filipović
Branko
B
Ajdzanović
Vladimir
V
Brkić
Dejan
D
Ristić
Natasa
N
Stojanoski
Milica Manojlović
MM
Nestorović
Natasa
N
Trifunović
Svetlana
S
Sekulić
Milka
M
D000367:Age Factors; D000818:Animals; D002784:Cholesterol / Q000097:blood* / Q000378:metabolism; D019833:Genistein / Q000008:administration & dosage* / Q000494:pharmacology; D006131:Growth Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D007279:Injections, Subcutaneous; D007529:Isoflavones / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D009919:Orchiectomy; D048789:Phytoestrogens / Q000008:administration & dosage* / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013739:Testosterone / Q000008:administration & dosage / Q000494:pharmacology; D014280:Triglycerides / Q000097:blood* / Q000378:metabolism
D006131:Growth Inhibitors; D007529:Isoflavones; D048789:Phytoestrogens; D014280:Triglycerides; D013739:Testosterone; C004742:daidzein; D002784:Cholesterol; D019833:Genistein