Influence of ginseng on mating behavior of male rats

Safety Assessment of Panax spp Root-Derived Ingredients as Used in Cosmetics

The Cosmetic Ingredient Review Expert Panel (Panel) reviewed the safety of 13 Panax spp root-derived ingredients as used in cosmetics. Panax "spp" indicates that multiple species within the genus are used in cosmetics, but not all species within that genus. Four species are being considered in this safety assessment. These ingredients function mostly as skin-conditioning agents-miscellaneous, fragrance ingredients, skin-conditioning agents-humectant, skin-conditioning agents-emollient, and cosmetic astringents. The Panel reviewed available data related to these ingredients and addressed the issue of pulegone, a constituent of these ingredients and other ingredients, such as peppermint oil. The Panel concluded that these Panax spp root-derived ingredients are safe in the practices of use and concentration as given in this safety assessment.

Safety Assessment of Panax Ginseng

Since the 1994 Dietary Supplement Health and Education Act, the consumption of botanical supplements has increased to the point where ginseng is the third best selling herbal supplement in the United States and it is now also being used as a flavoring agent in foods. The predominant pharmacologically active constituents of Panax are ginsenosides, at least 25 of which have been identified and are present in variable amounts and ratios to one another, depending on the particular species, variety, and conditions of growth. The toxicological profile of ginseng indicates it to be of rather low acute oral toxicity (LD50 > 5000 mg/kg for rats and mice, approximating 200 mg ginsenoside/kg.) No toxicological effects were identified in mini pigs at a dose of 2000 mg/kg (80 mg ginsenoside/kg). As concluded from a 90-day dog study and in reproduction studies in rats and mice, 15 mg/kg (∼ 0.6 mg ginsenoside/kg) was without effect. No effect was seen in rats administered 4000 mg/kg (160 mg ginsenoside/kg) for 20 days. There was no mutagenic activity observed in Salmonella typhimurium TM677 system with the use of ginseng in the presence or absence of metabolic activation. The no-observed-adverse-effectlevel (NOAEL) in rodents is likely within the range of 50 to 100 mg ginsenoside/kg. There are no confirmed reports of adverse reactions in humans attributed to ginseng alone. Importantly, no consistent symptomology or findings have been attributed to, or identified as being associated with, ginseng consumption. Ginseng extracts standardized at a concentration of 4 mg ginsenosides/100 mg capsule and given at a dose of up to 114 θ g ginsenoside/kg have not resulted in untoward effects when administered to humans for periods of up to 12 weeks.

Current Status and Clinical Studies of Oriental Herbs in Sexual Medicine in Korea

Erectile dysfunction (ED) is one of the most common diseases among aging men. Although previous studies have shown that type 5 phosphodiesterase inhibitors (PDE5-Is) are very effective for the treatment of ED, many researchers are currently attempting to identify therapeutic agents from natural sources with comparable or better effects than PDE5-Is. Herbal medicine is thought to be advantageous because it is natural; moreover, it not only treats isolated symptoms, but also maintains general well-being. Furthermore, since newly created chemical compound libraries have limited structural diversity with regard to pharmaceutical agents, more attention has recently been paid to the ability of oriental herbs to enhance physical health, including sexual function. Herein, we review the current status of Korean preclinical or clinical studies of the application of oriental herbs to sexual medicine.

Ginseng and male reproductive function

Ginseng is often referred to as the King of all herbs, and is found to be a promising agent to improve general well-being. Ginseng has also been reputed as an aphrodisiac, and is used to treat sexual dysfunction as well as to enhance sexual behavior in traditional Chinese medical practices. Data from animal studies have shown a positive correlation among ginseng, libido, and copulatory performances, and these effects have been confirmed in case-control studies in human. In addition, ginseng is found to improve the sperm quality and count of healthy individuals as well as patients with treatment-related infertility. These actions are mostly attributed to ginsenosides, the major pharmacological active components of ginseng. This review compiles the current knowledge about the multifaceted effects of ginseng on male reproductive function, and also focuses on its mechanisms of action that may represent novel therapeutic strategies for the treatment of male reproductive diseases or disorders.

Ginkgo biloba extract treatment increases noncontact erections and central dopamine levels in rats: role of the bed nucleus of the stria terminalis and the medial preoptic area

RATIONALE

Penile erection is necessary for successful copulation in males. The extract of Ginkgo biloba leaves (EGb 761) significantly facilitates copulation in male rats, but the effect of EGb 761 on noncontact erection (NCE) remains unknown.

OBJECTIVE

The present study was conducted to evaluate the influence of EGb 761 on NCE in male rats.

MATERIALS AND METHODS

Adult Long-Evans male rats were treated with 50 mg/kg of EGb 761 (experimental group) or distilled water (control group) by gavage for 14 days. The NCE test was carried out after 14 days of EGb 761 treatment, and the latency and the numbers of NCE were recorded. Approximately 14 h following the NCE behavioral tests, animals were sacrificed by means of decapitation, and levels of dopamine in the bed nucleus of the stria terminalis (BNST) and medial preoptic area (MPOA) were measured by means of high-pressure liquid chromatography with electrochemical detection.

RESULTS

Chronic treatment with EGb 761 significantly decreased the NCE latency, but increased the number of NCEs and the dopamine levels in the BNST and MPOA in rats compared to the controls.

CONCLUSION

Treatment with EGb 761 increased both NCEs and the dopamine contents in the BNST and the MPOA. These results suggest that enhanced NCEs in the rats administered with EGb 761 may be related to dopaminergic activity in the BNST and MPOA.

Different subregions of the medial preoptic area are separately involved in the regulation of copulation and sexual incentive motivation in male rats: a behavioral and morphological study

The purpose of this study was to investigate whether sexual incentive motivation and copulatory performance are regulated by different subregions of the medial preoptic area (MPOA). Sexual incentive motivation was measured by means of a partner preference test. Both copulatory behavior and sexual incentive motivation were tested in male rats treated with 50mg/kg of either EGb 761 or a vehicle (distilled water) by gavage for 14 days. Administration of EGb 761 increased the number of intromissions, but had no effect on the number of mounts, mount latency, intromission latency, ejaculation latency, or post-ejaculatory interval. In the partner preference test, the total duration of visits to estrous female rats in both of the groups was significantly different from the total duration of visits to sexually active males. EGb 761 treatment increased the number of ejaculations compared both to vehicle-treated controls on day 14 and the same group on day 0. In comparison with the controls, the EGb 761-treated group showed a significant increase in the number of tyrosine hydroxylase-expressing cells in the dorsal, but not the ventral, subregion of the MPOA, and significantly high dopamine levels in the MPOA. These results indicate that EGb 761 does not affect sexual incentive motivation, but facilitates copulatory performance in male rats, suggesting that the mechanisms responsible for sexual incentive motivation and copulatory performance may be associated with differential functions of MPOA subregions.

Use of ginseng in medicine with emphasis on neurodegenerative disorders

Ginseng, the root of Panax species, is a well-known herbal medicine. It has been used as a traditional medicine in China, Korea, and Japan for thousands of years and is now a popular and worldwide used natural medicine. The active ingredients of ginseng are ginsenosides which are also called ginseng saponins. Recently, there is increasing evidence in the literature on the pharmacological and physiological actions of ginseng. However, ginseng has been used primarily as a tonic to invigorate weak bodies and help the restoration of homeostasis. Current in vivo and in vitro studies have shown its beneficial effects in a wide range of pathological conditions such as cardiovascular diseases, cancer, immune deficiency, and hepatotoxicity. Moreover, recent research has suggested that some of ginseng's active ingredients also exert beneficial effects on aging, central nervous system (CNS) disorders, and neurodegenerative diseases. In general, antioxidant, anti-inflammatory, anti-apoptotic, and immune-stimulatory activities are mostly underlying the possible ginseng-mediated protective mechanisms. Next to animal studies, data from neural cell cultures contribute to the understanding of these mechanisms that involve decreasing nitric oxide (NO), scavenging of free radicals, and counteracting excitotoxicity. In this review, we focus on recently reported medicinal effects of ginseng and summarize the current knowledge of its effects on CNS disorders and neurodegenerative diseases.

Panax ginseng improves survival and sperm quality in guinea pigs exposed to 2,3,7,8-tetrachlorodibenzo- p-dioxin

OBJECTIVES

To further assess the effect of Panax ginseng on survival and sperm quality of guinea pigs exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

MATERIALS AND METHODS

Eighty male guinea pigs were divided into eight equal groups. The normal control (NC) group received vehicle and saline; one dose of 1 micro g/kg body weight TCDD was injected intraperitoneally into the single TCDD-treated (TT) and test groups (P100, P200, C100, C200); G and NC groups received vehicle instead of TCDD. P. ginseng water extract (PG-WE) was injected intraperitoneally at daily doses of 100 (G100, P100, C100) or 200 mg/kg body weight (G200, P200, C200). The PG-WE was administered to the P and G groups for 12 weeks from 1 week before TCDD exposure, and to the C groups for 10 weeks from 1 week after TCDD exposure. After a 4-week discontinuation of PG-WE treatment after the 13th week the surviving males were then tested for fertility by mating them with females. The litter size, death rate, male/female birth ratio and physical abnormalities of the progeny were investigated. After confirming delivery of the offspring, the parent males were killed at 40 weeks, their testes weighed and sperm quality assessed.

RESULTS

All TT animals died within 18 days after TCDD exposure, but 40-70% of the PG-WE-treated groups, depending on the group, survived until death at 40 weeks. All the surviving males were fertile regardless of TCDD exposure; there was no difference in litter size between the NC and test groups. Notably the death rate of progeny born to PG-WE-treated groups was lower than that of progeny born to the NC group. The progeny born to TCDD-exposed groups (P200 and C groups) had a preponderance of females. G Group animals had higher sperm quality than that of NCs even long after discontinuing PG-WE.

CONCLUSION

P. ginseng improves the survival rate and sperm quality in guinea pigs exposed to TCDD.

Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men

This study was a 12-week double blind placebo-controlled, randomized, parallel trial in which active treatment with different doses of Maca Gelatinizada was compared with placebo. The study aimed to demonstrate if effect of Maca on subjective report of sexual desire was because of effect on mood or serum testosterone levels. Men aged 21-56 years received Maca in one of two doses: 1,500 mg or 3,000 mg or placebo. Self-perception on sexual desire, score for Hamilton test for depression, and Hamilton test for anxiety were measured at 4, 8 and 12 weeks of treatment. An improvement in sexual desire was observed with Maca since 8 weeks of treatment. Serum testosterone and oestradiol levels were not different in men treated with Maca and in those treated with placebo (P:NS). Logistic regression analysis showed that Maca has an independent effect on sexual desire at 8 and 12 weeks of treatment, and this effect is not because of changes in either Hamilton scores for depression or anxiety or serum testosterone and oestradiol levels. In conclusion, treatment with Maca improved sexual desire.

Ginseng, sex behavior, and nitric oxide

In Asia, ginseng is commonly included in herbals used for the treatment of sexual dysfunction. Recent studies in laboratory animals have shown that both Asian and American forms of ginseng enhance libido and copulatory performance. These effects of ginseng may not be due to changes in hormone secretion, but to direct effects of ginseng, or its ginsenoside components, on the central nervous system and gonadal tissues. Indeed, there is good evidence that ginsenosides can facilitate penile erection by directly inducing the vasodilatation and relaxation of penile corpus cavernosum. Moreover, the effects of ginseng on the corpus cavernosum appear to be mediated by the release and/or modification of release of nitric oxide from endothelial cells and perivascular nerves. Treatment with American ginseng also affects the central nervous system and has been shown to significantly alter the activity of hypothalamic catecholamines involved in the facilitation of copulatory behavior and hormone secretion. Recent findings that ginseng treatment decreased prolactin secretion also suggested a direct nitric oxide-mediated effect of ginseng at the level of the anterior pituitary. Thus, animal studies lend growing support for the use of ginseng in the treatment of sexual dysfunction and provide increasing evidence for a role of nitric oxide in the mechanism of ginsenoside action.

Effect of American ginseng (Panax quinquefolium) on male copulatory behavior in the rat

The effects of American ginseng (Panax quinquefolium) on male rat copulatory behavior were investigated. Adult Sprague-Dawley rats were administered either 10, 50 or 100 mg/kg of Panax quinquefolium or a sesame oil vehicle per os (p.o.) for 28 days and copulatory behavior parameters were measured. Ginseng-treated male rats demonstrated a significant decrease in mount, intromission and ejaculation latencies compared to vehicle controls. Hormone analyses revealed no difference in plasma luteinizing hormone or testosterone levels between ginseng- and vehicle-treated animals; however, plasma prolactin levels were significantly reduced by all doses of ginseng tested. When male rats were treated with the 100 mg/kg dose of ginseng for 1, 14 or 28 days, mount and intromission latencies were significantly reduced at 14 and 28 days of daily ginseng treatment, whereas ejaculation latency was significantly reduced after 1 day of ginseng treatment when compared to vehicle controls. Plasma prolactin levels were also significantly decreased after 14 and 28 days of daily ginseng administration. There were no differences in body weight or in testes, seminal vesicle, anterior pituitary or spleen weights between ginseng- and vehicle-treated rats. These results demonstrate that P. quinquefolium significantly facilitates male copulatory behavior. The reduction in plasma prolactin levels suggests that ginseng-induced alterations in dopaminergic neurotransmission may play a role in the ability of P. quinquefolium to stimulate copulatory behavior in the male rat.

Evaluation of the ergogenic properties of ginseng

Ginseng has been used for several thousand years in the Orient as a tonic, prophylactic agent and 'restorative'. However, its efficacy has been established primarily through clinical experience as opposed to scientific verification of its pharmacological effects. Ginseng has been used by athletes as an ergogenic aid for many years, but there is an absence of compelling research evidence in support of its use for this purpose. Indeed, most of the support favouring the use of ginseng to enhance physical performance is of a testimonial nature. While studies with animals show that ginseng or its active components may prolong survival to physical or chemical stress, there is, generally, a lack of controlled research demonstrating the ability of ginseng to improve or prolong performance in fatigued humans.

Medicinal uses of ginseng and related plants in the Soviet Union: recent trends in the Soviet literature

Soviet scholars were the first to establish the fact that many araliaceous plants are resistogens (adaptogens). In the early 1950's, Soviet researchers pioneered the study of ginseng, which is considered to be the primary resistogen, and some other plants of the "ginseng group". A sizable volume of literature was published as a result of their studies. This article reports the results of Soviet research on the ginseng group for the past three decades, traces the progress of Soviet resistogen studies, and examines their current status. Because of its rarity, ginseng was found to be impractical as a source of raw material for the mass production of medicines. Consequently, Soviet scholars shifted the focus of their research from studying ginseng to other members of the ginseng group in order to find suitable substitutes. Four resistogenic plants were identified, studied and finally introduced into therapeutic practice, between 1955 and 1964. Eleutherococcus or eleuthero ginseng is considered to be the most important of these substitutes.