Huperzia saururus Lam. Trevis. (Lycopodiaceae) facilitates ejaculation in spinal cord transected male rats

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.

Ethnopharmacology of the club moss subfamily Huperzioideae (Lycopodiaceae, Lycopodiophyta): A phylogenetic and chemosystematic perspective

ETHNOPHARMACOLOGICAL RELEVANCE

The most speciose subfamily Huperzioideae (Lycopodiaceae, Lycopodiophyta) contains about 276 species, and some (ca. 20 species) have traditionally been used for the treatment of e.g., dementia, rheumatism and traumatic injury. Ethnopharmacological studies have also contributed to the development of huperzine A as a drug lead, a compound first isolated from the club moss Huperzia serrata (Thunb. ex Murray) Trevis.

AIM OF THE REVIEW

This review, with a phylogenetic and chemosystematic perspective, intends to highlight plant identification challenges in these taxa with examples from club moss phytochemical and ethnopharmacological studies, as these lead to data inconsistency and confusion. We suggest that future studies should include more details on plant identification including for example plant specimen images and DNA barcoding data. An integrative approach combining DNA barcoding and chemical fingerprinting is also introduced.

MATERIALS AND METHODS

Literature concerning ethnopharmacology and chemosystematics of Huperzioideae club mosses was searched from databases, e.g. PubMed, Web of Science, SciFinder, etc. Plant names were retrieved from original publications, and compared with up-to-date taxonomic and phylogenetic status. Ethnobotanical uses and herbal preparations were summarized. Production of certain pharmaceutically interesting compounds, such as the alkaloid huperzine A, was explored in a phylogenetic context.

RESULTS

Most traditionally used club mosses are associated with psychoactivity, followed by medicinal uses against rheumatism and traumatic injury. Herbs are often prepared as infusions, decoctions or tinctures, and this implies importance of water- or aqueous-alcohol-soluble substances, such as alkaloids. Most ethnopharmacological papers on club mosses need to update or correct plant names according to recent taxonomic nomenclature, and there are still a number of unidentified species with traditional use. Advanced LC-MS chemical profiling techniques, enable distinction of genotypes of the same species as well as annotation of potential chemotaxonomic markers. In combination with DNA barcoding, chemosystematics could also help us select plant taxa with higher pharmaceutical potential. Caution should be taken when interpreting bioassay results, in terms of compounds or extract preparation and bioassay standardization.

CONCLUSION

Huperzioideae club mosses have interesting pharmaceutical potential supported by ethnopharmacological investigations. Bioprospecting of these plants should be preceded by careful plant identification to produce consistent and reproducible data. We expect that DNA barcoding and LC-MS-based chemical fingerprinting could facilitate and improve ethnopharmaceutical studies in selection of club moss taxa.

Guibourtia tessmannii-induced fictive ejaculation in spinal male rat: involvement of D1, D2-like receptors

CONTEXT

Guibourtia tessmannii (Caesalpiniaceae) is a plant traditionally used as aphrodisiac. We previously reported the pro-ejaculatory effects of the aqueous and methanol extracts of G. tesmannii in spinal male rat. However, the mechanism underlying such effects has not been elucidated.

OBJECTIVE

This study characterizes the dopaminergic sub-type receptors involved in G. tesmannii-induced ejaculation in male Wistar rat.

MATERIALS AND METHODS

Urethane-anesthetized spinal male rats were intravenously treated with saline solution (1 mL/kg, control); dopamine (0.1 μmol/kg, reference); aqueous or methanol extracts of G. tesmannii (20 mg/kg) in the absence or presence of haloperidol (0.26 μmol/kg), a nonspecific dopaminergic receptor antagonist, Sch23390 (0.26 μmol/kg), a specific D1-like receptor antagonist or, sulpiride (0.26 μmol/kg), a specific D2-like receptor antagonist. Electromyography of the bulbospongiosus muscles and intraseminal pressure were recorded after urethral, penile and drug stimulations.

RESULTS

Urethral and penile stimulations, intravenous injection of dopamine or, aqueous and methanol extracts of G. tesmannii always triggered the expression of rhythmic contraction of the bulbospongiosus muscles with an average mean of 3.33 ± 0.43; 7.83 ± 0.85; 9.80 ± 0.86; 0.83 ± 0.54 and 2.67 ± 0.95 contractions, respectively. The intraseminal pressure was more expressed after urethral and penile stimulations (15.66 ± 1.58 and 13.60 ± 2.40 mmHg, respectively). In rats pretreated with haloperidol, Sch23390 or sulpiride, no ejaculation was recorded after intravenous injection of G. tesmannii extracts or dopamine.

DISCUSSION AND CONCLUSION

Guibourtia tesmannii-induced ejaculation requires the integrity of D1 and D2-like receptors. These findings further justify the ethno-medicinal claims of G. tesmannii as an aphrodisiac.

Aphrodisiac Activity of the Aqueous Crude Extract of Purple Corn ( Zea mays) in Male Rats

In the present study, the aphrodisiac properties of the purple corn (Zea mays) in male rats were analyzed. The aqueous crude extract of purple corn (at 25, 50, and 75 mg/kg) was administered to (a) copulating male rats and (b) anesthetized and spinal cord transected male rats. Behavioral parameters of copulatory behavior and parameters of the genital motor pattern of ejaculation previous to its inhibition, under the influence of the purple corn extract, are described. Administration of the aqueous crude extract of purple corn significantly facilitates the arousal and execution of male rat sexual behavior without significant influences on the ambulatory behavior. In addition, purple corn extract elicit a significant increase in the number of discharges of the ejaculatory motor patterns and in the total number of genital motor patterns evoked in spinal rats. The present findings show that the aqueous crude extract of purple corn possesses aphrodisiac activity.

Aphrodisiac activity of Phlegmariurus saururus in copulating and noncopulating male rats

BACKGROUND

Phlegmariurus saururus is popularly known in Argentina as aphrodisiac. For this reason, it was previously investigated and determined that the decoction of this plant elicits pro-ejaculatory activity and increases the ejaculatory potency in the Fictive Ejaculation Model. HYPOTHESIS/PURPOSE: the decoction of P. saururus facilitates sexual behavior in sexually experienced male rat and induces copulatory behavior in non-copulating male rats.

METHODS

The extraction method (decoction) was validated through Selectivity, Accuracy and Precision, by identification of the majority alkaloids, expressed as sauroxine. Male (sexually experienced and noncopulating) and female (receptive) Wistar rats were used to determine sexual behavior. Sildenafil was used as positive control. The following variables were evaluated: Mount Latency, Intromission Latency, Ejaculation Latency, Post Ejaculatory Interval, as well as the Mounts and Intromissions Number.

RESULTS

In sexually experienced male rats, P. saururus decoction stimulates sexual arousal and facilitates sexual execution. In noncopulating male rats, this decoction induces copulation with behavioral characteristics similar to sexually experienced animals.

CONCLUSION

P. saururus possesses aphrodisiac activity in copulating and noncopulating male rats.

Ejaculatory training lengthens the ejaculation latency and facilitates the functioning of the spinal generator for ejaculation of rats with rapid ejaculation

A spinal pattern generator controls the ejaculatory response. Central pattern generators (CPGs) may be entrained to improve the motor patterns under their control. In the present study we tested the hypothesis that training of the spinal generator for ejaculation (SGE) by daily copulation until ejaculation, could promote substantive changes in its functioning permitting a better SGE control of the genital motor pattern of ejaculation (GMPE) and, as a consequence, a normalization of the ejaculation latency of rats with rapid ejaculation. To that aim, we evaluated in sexually experienced male rats with rapid ejaculation (1) the effects of daily copulation to ejaculation, following different entrainment schedules, on their ejaculation latencies, (2) the impact of these different ejaculatory entrainment schedules upon the parameters of the GMPE and (3) the possible emergence of persistent changes in the functioning of the SGE associated to the daily ejaculation entrainment schedules. The data obtained show that intense ejaculatory training of rats with rapid ejaculation lengthens the ejaculation latency during copulation and augments the ejaculatory capacity of the SGE in this population when spinalized. Thus, present data reveal that like other CPGs, the SGE can be trained and put forward that training of the SGE by daily copulation to ejaculation might be a promising alternative that should be taken into consideration for the treatment of premature ejaculation.