PUNE, India—Furostanol glycosides isolated from fenugreek (as Testofen®, form Gencor ) increased muscle mass in castrated rats without affecting testosterone levels, in a recent study published is Phytotherapy Research ( 24: 1482–1488 (2010). DOI: 10.1002/ptr.3129 ). This anabolic activity has the potential to aid men as they enter so-called male menopause.
Andropause is an old-age disease associated with the loss of libido, loss of muscle mass and associated with decreased testosterone production. As the male body ages, gonadal function slowly declines with a resulting drop in serum testosterone, which can lead to multiple clinical manifestations such as a decrease in bone mass, learning factions, erectile functions, muscle mass and strength. On the other hand, fat mass increases.
Fenugreek ( Trigonella foenum ) has long been used in the traditional Indian systems of medicine for the treatment of various ailments, including sexual health. Western medicine often looks to testosterone replacement to treat erectile dysfunction, which has been shown to compromise the overall quality of life, and increase depression, anxiety and loss of self-esteem. Erectile dysfunction may also signal underlying disease including diabetes, hypertension and cardiovascular disease (CVD). A potential risk of testosterone replacement therapy is an increase in the incidence of prostate cancer.
In the present investigation, Testofen at dose of 35 mg/kg/d significantly increased the weight of the levator ani muscle without increasing the blood urea nitrogen (BUN) similar to exogenous testosterone (10 mg/kg) treatment, indicating anabolic activity. Anabolic agents induce positive nitrogen balance in living organisms. Another bioassay for anabolic activity involves measurement of the increase in weight of the levator ani muscle. This measure correlates well with the nitrogen retention bioassay and the two are usually performed for the determination of anabolic activity.
This current study used Testofen, a furostanol glycoside fraction of Trigonella foenum-graecum , in immature castrated male Wistar rats to investigate anabolic and androgenic activity. The Indian researchers also investigate the effect of Testofen on testicular histology in non-castrated immature rats. Both the castrated and intact rats were divided into the following groups: (I) Control (distilled water), (II) Testofen at 10 mg/kg/d, (III) Testofen at 35 mg/kg/d, (IV) and testosterone (10 mg/kg bi-weekly) for four weeks. At the end of the study, blood was withdrawn, serum testosterone and BUN were measured. Animals were killed and reproductive organs were excised and weighed.
Testosterone increased the body weight of rats significantly (P<0.001) from 151.6 to 254.2 g (68.94 percent increase), whereas the weight of 35-mg/kg-Testofen-treated rats was increased from 151.6 to 193.8 g (28 percent increase). The increase in body weight of 10-mg/kg-Testofen-treated rats was not significant compared with the control group.
Testosterone significantly increased the seminal vesicle, ventral prostate and levator ani weight, but not the penis weight. Testofen at 35 mg/kg, on the other hand, significantly (P<0.001) increased the weights of the levator ani muscle, but failed to increase other organ weights. At the lower dose of 10 mg/kg, Testofen did not increase organ weights.
Testofen at both doses did not change the testosterone level in either the castrated or intact rats, whereas testosterone treatment caused significant (P<0.001) increases in serum testosterone level.
The BUN in castrated rats was 33.44 mg/dL in the control group. The BUN was found to be 18.8 mg/dL in both the higher dose of Testofen and testosterone treatment groups. However, the lower dose of Testofen did not cause a significant change in BUN compared with the control group.
It is postulated that testosterone that is converted peripherally to dihydrotestosterone (DHT) by 5-alpha reductase is responsible for the prostate risk associated with testosterone therapy. DHT has a role in the growth of prostatic tissue and therefore can influence lower urinary tract symptoms. Endogenous testosterone in the circulation can be free (unbound), weakly bound to albumin, or tightly bound to sex hormone binding globulin (SHBG). The free and albumin-bound testosterone is available for use by the body. The largest percentage, however, is bound to SHBG and is unavailable for use in the body.
The results obtained in the present study showed that fenugreek furostanol glycoside possessed anabolic activity (increased muscle mass) without affecting total serum testosterone levels in castrated rats. The probable mechanism for this action may be due to increased availability of testosterone by dissociating it from the stored form, i.e., SHBG.