Botanical therapies in sexual dysfunction

Evaluation of the potential aphrodisiac activity of sesquiterpenoids from roots of Ferula huber-morathii Peşmen in male rats

ETHNOPHARMACOLOGICAL RELEVANCE

Several species of Ferula L. genus have been used in traditional Turkish medicine as aphrodisiac to treat male sexual dysfunction. Especially, roots and oleo gum resin of F. elaeochytris Korovin, F. communis L., F. assa-foetida L. and F. gummosa Boiss. were claimed to be used for aphrodisiac activity, menstrual regulation and treatment of gastric pain in Anatolia. Ferula L. is represented by 23 taxa in Turkey, 13 of which are endemic species. F. huber-morathii Peşmen (FHM), an endemic plant, is popularly known as ''helizan, çağşır''.

AIM OF THE STUDY

This study aimed to isolate sesquiterpenoids from the roots of Ferula huber-morathii (FHM) and to confirm their aphrodisiac potential in male rats.

MATERIAL AND METHODS

In a preliminary experiment, the effects of aqueous (H₂O) and chloroform (CHCl₃) extracts of FHM were tested for their potential aphrodisiac activities in male rats. Then, sesquiterpene derivatives were isolated from the active chloroform extract of FHM roots (FHM-R) and characterized (TLC, 1D, 2D NMR, HR-MS and CD). Moreover, some of the isolates with adequate quantities were evaluated for their possible aphrodisiac effects on male rats. Single doses (10 mg/kg BW) of sildenafil citrate (SC, positive control), gummosin, mogoltavidin, deacetylkellerin, ferukrin acetate with kellerin, elaeochytrin-A and ferutinin were administered orally by gavages to male Wistar albino rats. Mount latency (ML), mount frequency (MF), intromission latency (IL), intromission frequency (IF), ejaculation latency (EL) and postejaculatory interval (PEI) were studied. In addition, copulatory efficiency (CE) and intercopulatory efficiency (ICE) were calculated.

RESULTS

The preliminary experiment revealed that the chloroform extract was the main source of the active compounds as it showed the higher aphrodisiac activity while the aqueous extract was found to be inactive. Eleven sesquiterpene derivatives, viz. gummosin, mogoltavidin, farnesiferol A, deacetylkellerin, ferukrin acetate, kellerin, teuclatriol, feruhermonin C, ferutinin, elaeochytrin A and teferidin, were isolated from the FHM-CHCl₃ extract. Oral administration of deacetylkellerin, elaeochytrin-A and ferutinin significantly increased MF and IF. The ML and IL were significantly reduced, and ejaculation latencies were prolonged. Administration of these sesquiterpenoids also reduced the PEI. The present results revealed that ferutinin was the most effective aphrodisiac compound compared to other sesquiterpenoids. The results of 10 mg/kg of ferutinin are comparable to SC, the positive control. The results revealed that gummosin, mogoltavidin and ferukrin acetate with kellerin did not significantly alter the aphrodisiac parameters.

CONCLUSIONS

This study has established that the CHCl₃ extract of FHM root contains sesquiterpene derivatives, especially coumarin ethers and benzoic esters. Findings of the present study demonstrate that the chloroform extract and some of the sesquiterpene derivatives significantly stimulates sexual behavior in male rats, thus suggesting that F. huber-morathii possesses an aphrodisiac activity.

Parquetina nigrescens leaves: chemical profile and influence on the physical and biochemical indices of sexual activity of male Wistar rats

OBJECTIVE

The leaves of Parquetina nigrescens have been claimed in folk medicine to be useful for managing sexual dysfunction, but there is inadequate scientific evidence for this claim. This investigation was conducted to assess the effects of aqueous leaf extract of Parquetina nigrescens (AEPN) in rats induced with sexual dysfunction.

METHODS

Male rats were allocated into various groups after being induced into sexual dysfunction with paroxetine hydrochloride. The groups were treated with distilled water, PowMaxM (reference drug), and the AEPN at 20, 40 and 80 mg/kg body weight (BW) respectively for 7 d. Frequencies of mount (MF), intromission (IF), ejaculation (EF), as well as latencies of mount (ML), intromission (IL) and post-ejaculatory interval (PEI) were progressively monitored with receptive female rats on days 1, 3 and 7. The precentage of mounted, intromitted, and ejaculated rats, intromission ratio (IR), copulatory efficiency (CE) and intercopulatory interval (ICI) were also computed. Standard methods were employed to determine the levels of serum luteinizing and follicle stimulating hormones (LH and FSH), testosterone, nitric oxide (NO) and the activity of phosphodiesterase V (PDE5).

RESULTS

The plant contained alkaloids, saponins, flavonoids, cardiac glycosides, steroids, tannins, phlobatannins, cardenolides, phenolics, anthraquinones and triterpenes with alkaloids (2.32 mg/g) occurring in greatest quantity while flavonoids, anthraquinones and cardenolides (0.01 mg/g, each) were the least. All the 20 standard amino acids were detected in the plant leaf, with the lowest concentration being 0.30 mg/g for methionine and the highest being 2.12 mg/g for cysteine. Furthermore, P. nigrescens leaves contained Na, K, Fe, Mg, Zn, Ca, Cu, Mn, P, Pb, Cd, Ni, Cr, and Co, with Fe present in the highest and Co the lowest concentrations. Paroxetine significantly (P<0.05) reduced MF, IF, EF, percentage mounted , intromitted, ejaculated, IR, CE, serum testosterone, LH, FSH and NO, while ML, IL, PEI, IF and PDE5 were significantly (P<0.05) increased and/or prolonged. The AEPN significantly reversed these paroxetine-treatment-related alterations with most profound activity at the highest dose of 80 mg/kg BW, similar to that of the PowMaxM-treated animals.

CONCLUSION

The AEPN restored both the physical and biochemical indices of male sexual activity/competence via changes in reproductive hormones, NO and PDE5 activity. The pro-sexual activity, attributed to a myriad of mineral, amino acid and secondary metabolite constituents, was best at 80 mg/kg BW of AEPN.

Standardized Morinda citrifolia L. and Morinda elliptica L. leaf extracts alleviated fatigue by improving glycogen storage and lipid/carbohydrate metabolism

The antifatigue properties of Morinda elliptica (ME) leaf were compared with Morinda citrifolia (MC) leaf extracts. Sixty Balb/C mice were administered (N = 10): control water, standardized green tea extract (positive control 200 mg/kg body weight [BW]), either 200 or 400 mg MC/kg BW, or either 200 or 400 mg ME/kg BW). The mice performances, biochemical, and mRNA expressions were evaluated. After 6 weeks, the weight-loaded swimming time to exhaustion in the mice consuming 400 mg MC/kg, were almost five times longer than the control mice. The gene expressions analysis suggested the extracts enhanced performance by improving lipid catabolism, carbohydrate metabolism, electron transport, antioxidant responses, energy production, and tissue glycogen stores. The MC and ME extracts enhanced stamina by reducing blood lactate and blood urea nitrogen levels, increasing liver and muscle glycogen reserve through augmenting the glucose metabolism (glucose transporter type 4 and pyruvate dehydrogenase kinase 4), lipid catabolism (acyl-Coenzyme A dehydrogenases and fatty acid translocase), antioxidant (superoxide dismutase 2) defence responses, electron transport (COX4I2), and energy production (PGC1α, NRF1, NRF2, cytochrome C electron transport, mitochondrial transcription factor A, UCP1, and UCP3) biomarkers. The MC (containing scopoletin and epicatechin) was better than ME (containing only scopoletin) or green tea (containing epicatechin and GT catechins) for alleviating fatigue.

Long-term feeding of hydroalcoholic extract powder of Lepidium meyenii (maca) enhances the steroidogenic ability of Leydig cells to alleviate its decline with ageing in male rats

This study examined whether feeding hydroalcoholic extract of Lepidium meyenii (maca) to 8-week-old (sexually maturing) or 18-week-old (mature) male rats for more than a half year affects serum testosterone concentration and testosterone production by Leydig cells cultured with hCG, 22R-hydroxycholesterol or pregnenolone. Testosterone concentration was determined in the serum samples obtained before and 6, 12, 18 and 24 weeks after the feeding, and it was significantly increased only at the 6 weeks in the group fed with the maca extract to maturing rats when it was compared with controls. Testosterone production by Leydig cells significantly increased when cultured with hCG by feeding the maca extract to maturing rats for 27 weeks (35 weeks of age) and when cultured with 22R-hydroxycholesterol by feeding it to mature rats for 30 weeks (48 weeks of age). Overall testosterone production by cultured Leydig cells decreased to about a half from 35 to 48 weeks of age. These results suggest that feeding the maca extract for a long time to male rats may enhance the steroidogenic ability of Leydig cells to alleviate its decline with ageing, whereas it may cause only a transient increase in blood testosterone concentration in sexually maturing male rats.

Effect of chronic administration of sildenafil citrate (Viagra) on the histology of the retina and optic nerve of adult male rat

BACKGROUND

Abnormal vision has been reported by 3% of patients treated with sildenafil citrate (Viagra). Although many men use Viagra for an extended period for treatment of erectile dysfunction, the implications of the long term-daily use of it on the retina and optic nerve are unclear.

AIM OF THE WORK

To investigate the effect of chronic daily use of sildenafil citrate in a dose equivalent to men preferred therapeutic dose on the histology of the retina and optic nerve of adult male rat.

MATERIAL & METHODS

Eighteen adult male Wistar rats were equally divided into three groups. Group I: control. Group II: treated with sildenafil citrate orally (10mg/kg/day) for 8 weeks. Group III (withdrawal): treated as group II and then left for 4 weeks without treatment. Specimens from the retina and optic nerve were processed for light and electron microscopy.

RESULTS

In sildenafil citrate treated group, the retina and optic nerve revealed vacuolations and congested blood capillaries with apoptotic endothelial and pericytic cells, and thickened basal lamina. Caspase-3 (apoptotic marker) and CD31 (endothelial marker) expression increased. Glial cells revealed morphological changes: Müller cells lost their processes, activated microglia, astrocytic clasmatodendrosis, degenerated oligodendrocytes surrounded by disintegrated myelin sheathes of the optic nerve fibers. The retina and optic nerve of the withdrawal group revealed less vacuolations and congestion, and partial recovery of the glial cells.

CONCLUSION

Chronic treatment with sildenafil citrate (Viagra) caused toxic effect on the structure of the retina and optic nerve of the rat. Partial recovery was observed after drug withdrawal.

Clinical Assessment of Tribulus terrestris Extract in the Treatment of Female Sexual Dysfunction

This is a qualitative–quantitative study based on hospital records of female patients of reproductive age, presenting sexual dysfunction, and treated with 250 mg Tribulus terrestris extract (1 tablet thrice daily for 90 days). Safety monitoring included vital signs, physical examination, laboratory tests, and occurrence of adverse events. Efficacy analysis included results of the Female Sexual Function Index (FSFI), dehydroepiandrosterone (DHEA) levels together with total and free testosterone, and the patient and physician assessments. There was a statistically significant improvement in total FSFI scores (P < 0.0001) post-treatment, with improvement among 106 (88.33%) subjects. There was a statistically significant (P < 0.0001) increase in the level of DHEA, while the levels of both serum testosterone (P = 0.284) and free testosterone decreased (P < 0.0001). Most adverse events recorded were related to the gastrointestinal tract. Physical examination showed no significant changes post-treatment. Based on the results, it is concluded that the T. terrestris extract is safe and effective in the treatment of female sexual dysfunction.

Pueraria tuberosa DC extract improves androgenesis and sexual behavior via FSH LH cascade

The aim of this study was to investigate the effects of ethanolic extract of Pueraria tuberosa (PT) on sexual behaviour and androgenic activity. Male albino rats were divided into four groups of six animals each: control group 1 (2% acacia solution), PT-treated group 2 (50 mg/Kg), PT-treated group 3 (100 mg/Kg), and PT-treated group 4 (150 mg/Kg). Sexual behavior of male rats in the presence of a female rat was recorded. The treated groups were evaluated for sexual parameters. The extract was characterized using LC-MS. The effect of treatment on anabolic and weight of secondary sexual organs was determined. The histological changes in section of testis and epididymis after treatment were observed. Sperm count in epididymis and fructose content in seminal vesicles were also measured. Levels of hormones like FSH, LH, and T were determined. A dose-dependent increase in sexual behaviors was evidenced in the animals of extract treated groups. Increase in testis weight was recorded in PT. At the highest dose PT also affects the hormones level. The four compounds namely puerarin, daidzein, biochanin-A and formononetin were identified in ethanolic extract using LC-MS. It concluded that PT extract possesses androgenic effect and it significantly increased the sexual behaviour and hormones level.

Effects of Korean ginseng berry extract on sexual function in men with erectile dysfunction: a multicenter, placebo-controlled, double-blind clinical study

Ginseng is beneficial for many aspects of human physiology, including sexual function. In this study, we have evaluated the efficacy and safety of an extract of ginseng berry, which has a ginsenoside profile distinct from other parts of the plant, on sexual function in men with erectile dysfunction. In all, 119 men with mild-to-moderate ED participated in a multicenter, randomized, double-blind, parallel, placebo-controlled clinical study. They were administered 4 tablets of either standardized Korean ginseng berry (SKGB, 350 mg ginseng berry extract per tablet), or placebo, daily, for 8 weeks. Efficacy was assessed with the International Index of Erectile Function (IIEF)-15 and premature ejaculation diagnostic tool (PEDT) at the end of the 4th and 8th week. We observed that the total and each of the individual domain scores of IIEF-15 increased from 40.95 ± 7.05 to 46.19 ± 12.69 significantly in the SKGB by the 8th week (P<0.05). The erectile function domain of IIEF changed slightly from 17.17 ± 2.57 to 18.59 ± 5.99 in the SKGB group by the 8th week (P<0.05). In addition, PEDT scores significantly improved from 9.14 ± 4.57 to 7.97 ± 4.4 and 7.53 ± 4.26 in the SKGB group after 4 and 8 weeks of treatment (P<0.05). Safety markers including hormone and lipid in the blood were assessed at the end of the 4th and 8th week and they remained unchanged. Oral administration of the SKGB extract improved all domains of sexual function. It can be used as an alternative medicine to improve sexual life in men with sexual dysfunction.

Maca (L. meyenii) for improving sexual function: a systematic review

Background

Maca (Lepidium meyenii) is an Andean plant of the brassica (mustard) family. Preparations from maca root have been reported to improve sexual function. The aim of this review was to assess the clinical evidence for or against the effectiveness of the maca plant as a treatment for sexual dysfunction.

Methods

We searched 17 databases from their inception to April 2010 and included all randomised clinical trials (RCTs) of any type of maca compared to a placebo for the treatment of healthy people or human patients with sexual dysfunction. The risk of bias for each study was assessed using Cochrane criteria, and statistical pooling of data was performed where possible. The selection of studies, data extraction, and validations were performed independently by two authors. Discrepancies were resolved through discussion by the two authors.

Results

Four RCTs met all the inclusion criteria. Two RCTs suggested a significant positive effect of maca on sexual dysfunction or sexual desire in healthy menopausal women or healthy adult men, respectively, while the other RCT failed to show any effects in healthy cyclists. The further RCT assessed the effects of maca in patients with erectile dysfunction using the International Index of Erectile Dysfunction-5 and showed significant effects.

Conclusion

The results of our systematic review provide limited evidence for the effectiveness of maca in improving sexual function. However, the total number of trials, the total sample size, and the average methodological quality of the primary studies were too limited to draw firm conclusions. More rigorous studies are warranted.

Hormesis and medicine

Evidence is presented which supports the conclusion that the hormetic dose-response model is the most common and fundamental in the biological and biomedical sciences, being highly generalizable across biological model, endpoint measured and chemical class and physical agent. The paper provides a broad spectrum of applications of the hormesis concept for clinical medicine including anxiety, seizure, memory, stroke, cancer chemotherapy, dermatological processes such as hair growth, osteoporosis, ocular diseases, including retinal detachment, statin effects on cardiovascular function and tumour development, benign prostate enlargement, male sexual behaviours/dysfunctions, and prion diseases.

The effect of saffron, Crocus sativus stigma, extract and its constituents, safranal and crocin on sexual behaviors in normal male rats

In this study, the aphrodisiac activities of Crocus sativus stigma aqueous extract and its constituents, safranal and crocin, were evaluated in male rats. The aqueous extract (80, 160 and 320mg/kg body wt.), crocin (100, 200 and 400mg/kg body wt.), safranal (0.1, 0.2 and 0.4ml/kg), sildenafil (60mg/kg body wt., as a positive control) and saline were administered intraperitoneally to male rats. Mounting frequency (MF), intromission frequency (IF), erection frequency (EF), mount latency (ML), intromission latency (IL) and ejaculation latency (EL) were the factors evaluated during the sexual behavior study. Crocin, at all doses, and the extract, especially at doses 160 and 320mg/kg body wt., increased MF, IF and EF behaviors and reduced EL, IL and ML parameters. Safranal did not show aphrodisiac effects. The present study reveals an aphrodisiac activity of saffron aqueous extract and its constituent crocin.