A novel aphrodisiac compound from an orchid that activates nitric oxide synthases

Botanical Medicine and Natural Products Used for Erectile Dysfunction

INTRODUCTION

Erectile dysfunction is the persistent or recurrent inability to achieve or maintain an erection sufficient for intercourse. Despite various treatment options, not all patients respond adequately and their usefulness is limited by adverse effects and cost. Botanical medicine and natural products have been and continue to be invaluable and untapped sources of new drugs, including potentially those to treat erectile dysfunction.

OBJECTIVES

To review the current literature on botanical medicine traditionally used as aphrodisiacs and treatment of erectile dysfunction, in particular, scientific and clinical investigations that have been performed, possible active phytoconstituents, and mechanisms of action and to identify gaps in current knowledge to better guide future research efforts.

METHODS

A comprehensive literature search was conducted via PubMed, Scopus, Science Direct, and Web of Science on English publications, using various keywords, for example, "herb", "natural product", combined with "erectile dysfunction", "aphrodisiac", and "sexual performance".

RESULTS

369 relevant articles studying medicinal plants used for erectile dysfunction were analyzed. A total of 718 plants from 145 families and 499 genera were reported to be used traditionally as aphrodisiacs and treatment of erectile dysfunction. Top plants used include Pausinystalia johimbe, Lepidium meyenii, and Panax ginseng. Different plant parts are used, with roots being the most common. Less than half of these plants have been evaluated scientifically, using various research methodologies. Clinical trials conducted were collated. Current scientific investigation shows mixed results about their usefulness in enhancing sexual performance. A limited number of studies have attempted to elucidate the mechanisms of action of these medicinal plants.

CONCLUSION

A comprehensive literature review on botanical medicine and natural products used for treatment of erectile dysfunction was successfully conducted. Although medicinal plants serve as a potential source of lead compounds for erectile dysfunction drugs, further studies are warranted to further evaluate their efficacy and safety. SinVJ-E, Anand GS, Koh H-L. Botanical Medicine and Natural Products Used for Erectile Dysfunction. Sex Med Rev 2020;XX:XXX-XXX.

How bad is brazilian ginseng extract for reproductive parameters in mice?

Properties attributed to the Panax ginseng are also attributed to the Brazilian ginseng, such as adaptogenic and aphrodisiac effects. There are studies demonstrating that the Brazilian ginseng (BGE) possibly increases the serum levels of testosterone and nitric oxide in mice and rats. The present study aimed to evaluate the effects of its extract on male fertility and sperm quality. Male Swiss mice (n = 60) were divided into six groups. The control animals were provided 0.5 mL of water, and 0.5 mL of water containing 7 mg/kg per day (d) sildenafil citrate. Other animals were treated with BGE at 100 mg/kg/d, 200 mg/kg/d, and 400 mg/kg/d by gavage for 42 days. Finally, animals from the last group received 200 mg/kg BGE every 3 days (3-3d) by gavage for 42 days. The results showed a reduction in the number of resistant spermatids in the testis and damage to daily sperm production, culminating in a reduction in the number of epididymal spermatozoa. Although the sperm quality decreased in all experimental animals, only males treated with BGE 100 mg/kg/d showed pre and post implantation embryo losses. We concluded that BGE alters sperm viability compromising the embryonic development after implantation.

Plants in the management of male infertility

This review attempts to collate existing data and provide the perspectives for future studies on the effects of plants on the male gonads. For many of these medicinal plants such as Lepidium meyenii, Rupus coreanus, Tribulus terrestres, Panax ginseng, Petasites japonicas, Apium graveolens, Eurycoma longifólia, Pedalium murex, Corchorus depressus, Mucuna pruriens, Astragalus membranaceus, Nigella sativa, Crataegus monogyna, Fagara tessmannii, Phaleria macrocarpa, Anacyclus pyrethrum, Cynomorium songaricum and Morinda officinalis, the mechanism of actions of their active principles and crude extracts has been shown in both laboratory animals, in vitro, and human studies, and includes their antioxidant, anti-inflammatory, spermatogenesis-inducing, aphrodisiac, smooth muscle relaxing and androgenic properties. Several active chemical leads including glucosinolates, anthocyanins, protodioscin, ginsenosides, sesquiterpenes, phyto-oestrogens, quassinoids, diosgenin, thymoquinone, proanthocyanidins and bajijiasu isolated from these plants are known to have target effects on the testis, but efforts have been limited in their application at the clinical level. There still appear to be many more extracts of medicinal plants that have not been characterised to determine the phytochemicals unique to them that have target effects on the gonads. Further, collaborative efforts at isolating pro-drug candidates from medicinal plants for studies at the molecular, cellular and clinical level towards elucidating their mechanisms of action on the testes are therefore warranted in the light of the current male fertility crisis.

Genus Vanda: A review on traditional uses, bioactive chemical constituents and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Vanda (Family: Orchidaceae) comprises about 73 species mainly distributed in Southeast Asia. Plants belonging to this genus are being used in the traditional medicine systems in Asian countries specially in India, Nepal, China and Bangladesh.

AIM OF THE REVIEW

The aim of this work was to review the scientific work about medicinal orchids of the genus Vanda regarding their traditional uses, reported bioactive components, and pharmacological activities.

MATERIALS AND METHODS

The information related to traditional uses, pharmacological activities, and bioactive compounds was systematically collected from the scientific literature databases including SciFinder, Scopus, PubMed and Google Scholar, published books and conference proceedings.

RESULTS

The literature survey revealed diverse traditional uses of different species of Vanda, mainly against indigestion, wounds, hepatitis, dyspepsia, bronchitis, piles, rheumatism, and bone fracture. However, only few of them are investigated scientifically for their chemical constituents and pharmacological activities. Bioactive compounds including eucomic acid derivatives, phenanthrene derivatives and other phenolic compounds are reported from Vanda species. Different extracts were so far evaluated for number of pharmacological activities including neuroprotective, anti-aging, antimicrobial, anti-inflammatory, antioxidant, membrane stabilizing, wound healing and hepato-protective activities.

CONCLUSION

Vanda spp. are of much significance as ornamental flowers, but also used widely in traditional medicines and have potential for their diverse pharmacological activities. However, many members of the genus Vanda need further detailed studies regarding chemical constituents and mechanism-based pharmacological activities. Similarly, further studies should also focus on the conservation, cultivation and sustainable utilization of these species.

Vanda roxburghii: an experimental evaluation of antinociceptive properties of a traditional epiphytic medicinal orchid in animal models

BACKGROUND

Ethnopharmacological approach has explored several leads from plant sources to identify potential new drugs for various diseases including pain. Vanda roxburghii R. Br., an epiphytic orchid is widely distributed throughout Bangladesh. The root of this plant has a folkloric reputation to treat inflammations, fever, dyspepsia, bronchitis, hiccough, piles, snake bites, and diseases of the nervous system. In this study therefore, we aimed to investigate antinociceptive and cytotoxic properties of the extracts from the root of V. roxburghii.

METHODS

Dried powder of aerial root of V. roxburghii was extracted with methanol (VRM) and the resultant was fractionated into petroleum ether (VRP), chloroform (VRC), ethyl acetate (VRE), and residual aqueous fraction (VRA). The antinociceptive effect of the extracts was evaluated in mice using acetic acid-induced writhing, formalin injection, and hot plate tests. The brine shrimp lethality bioassay in vitro was used to evaluate cytotoxic activity of the plant extracts.

RESULTS

In the acetic acid-induced writhing test, mice treated with different fractions (12.5, 25, and 50 mg/kg, i.p.) exhibited reduced number of writhing. Amongst, VRE showed the highest activity at all three concentrations (43.65, 71.34, and 80.23%, respectively) in a dose-dependent manner. Secondly, VRC (12.5, 25, and 50 mg/kg, i.p.) displayed the highest reduction of paw licking time in mice during the first phase of the formalin test (by 15.00, 37.05, and 56.44%, respectively) as well as during the second phase of the test (by 20.55, 49.08, and 59.81%, respectively). In hot plate test, VRE treatment at doses of 25 and 50 mg/kg both increased the highest latency time after 30 min. All fractions showed lower cytotoxicity compared with the standard drug vincristine sulfate in the brine shrimp bioassay.

CONCLUSION

Overall studies suggest that the root of V. roxburghii is effective as a potent analgesic with lower toxicity. Our findings support previous claims of traditional uses of V. roxburghii in different inflammatory disorders.

Antinociceptive and cytotoxic activities of an epiphytic medicinal orchid: Vanda tessellata Roxb

BACKGROUND

Vanda tessellata (Orchidaceae) has been used in different sorts of ailments such as inflammations, rheumatism, dysentery, bronchitis, dyspepsia and fever in folk medicine. In this study we evaluated the antinociceptive and cytotoxic effect of methanol and aqueous extracts of V. tessellata leaf.

METHODS

Oral administration of V. tessellata aqueous (VTA) and methanol (VTM) leaf extracts at 200 and 400 mg/kg body weight (bw) doses were assessed for antinociceptive activity in acetic acid-induced writhing test, hot plate test, and tail immersion test in mice. In this study we also screened for cytotoxicity of the extracts by the brine shrimp (Artemia salina) lethality assay.

RESULTS

The extracts, at both doses, exhibited a significant (p < 0.05 - < 0.01) dose-dependent antinociceptive activity in hot plate and tail immersion test. The reaction time was increased to the thermal stimuli at 200 and 400 mg/kg doses up to 90 min. In acetic acid-induced writhing test, oral administration of VTA and VTM (200 and 400 mg/kg) also decreased the writhing significantly while compared to control. The dose 400 mg/kg showed maximum percentage of pain inhibition 42.37% and 45.08% for VTA and VTM respectively. Diclofenac sodium (10 mg/kg) and nalbuphine (10 mg/kg) were used as reference antinociceptive drugs. Very low cytotoxicity was observed on brine shrimps lethality assay.

CONCLUSIONS

The leaf extract has potential antinociceptive activity with minimum cytotoxicity. The present study supports the use of V. tessellata in different inflammatory disorders.

A review on plants used for improvement of sexual performance and virility

The use of plant or plant-based products to stimulate sexual desire and to enhance performance and enjoyment is almost as old as the human race itself. The present paper reviews the active, natural principles, and crude extracts of plants, which have been useful in sexual disorders, have potential for improving sexual behaviour and performance, and are helpful in spermatogenesis and reproduction. Review of refereed journals and scientific literature available in electronic databases and traditional literature available in India was extensively performed. The work reviews correlation of the evidence with traditional claims, elucidation, and evaluation of a plausible concept governing the usage of plants as aphrodisiac in total. Phytoconstituents with known structures have been classified in appropriate chemical groups and the active crude extracts have been tabulated. Data on their pharmacological activity, mechanism of action, and toxicity are reported. The present review provides an overview of the herbs and their active molecule with claims for improvement of sexual behaviour. A number of herbal drugs have been validated for their effect on sexual behavior and fertility and can therefore serve as basis for the identification of new chemical leads useful in sexual and erectile dysfunction.