Pharmacological and neurochemical evidence for antidepressant-like effects of the herbal product Catuama

The traditional use of native Brazilian plants for male sexual dysfunction: Evidence from ethnomedicinal applications, animal models, and possible mechanisms of action

ETHNOPHARMACOLOGICAL RELEVANCE

Sexual dysfunction is a multifactorial health condition characterized by distressing disturbances in the sexual response and libido, leading to an inability to maintain penile erection and achieve pleasure. Considering the huge Brazilian biodiversity, many plants are traditionally used for aphrodisiac purposes. However, the use of native medicinal plants as sexual boosters in Brazil has been poorly studied.

AIM OF THE STUDY

This review focuses on the composition, pharmacology, and results of experimental trials of the main native plants used in Brazilian folk medicine with alleged aphrodisiac effects. We aimed to provide a state-of-the-art reference for research on herbs for the treatment of male sexual dysfunction by summarizing and discussing the main studies found.

MATERIALS AND METHODS

The relevant information was collected by searching keywords (aphrodisiac, sexual tonic, sexual stimulant, sexual vigor stimulant, sexual impotency, erectile dysfunction, etc.) from books containing primary surveys conducted in the original communities and bibliographic surveys prepared by authors linked to the national academic and scientific environment edited in Brazil. Preclinical and clinical studies of the compiled plant species were performed using scientific databases (Scopus, PubMed, SciELO, and SciFinder).

RESULTS

Seventy-four plant species belonging to 44 families used in Brazil to treat sexual dysfunction were compiled from ethnopharmacological literature. Fourteen plants, including Pfaffia glomerata (Spreng.) Pedersen, Aspidosperma quebracho-blanco Schltdl., Anemopaegma arvense (Vell.) Stellfeld ex de Souza, Mimosa pudica L., Heteropterys tomentosa A. Juss., Trichilia catigua A. Juss., and Turnera diffusa Willd. ex Schult. were pharmacologically studied to confirm these therapeutic properties. Probable modes of action include antioxidant and androgenic activities, inhibition of the PDE5 enzyme, increase in NO levels, and activation of dopaminergic and noradrenergic pathways. In addition, several different species popularly known as "catuaba" were identified, leading to adulterations and controversial effects.

CONCLUSION

The overall results of the present review of Brazilian folk literature reveal that Brazil has a long tradition of using plants with potential aphrodisiac effects. However, further research is required to identify, characterize, and standardize the active ingredients and herbal preparations used in aphrodisiacs.

Effects of the consumption of guarana on human health: A narrative review

Guarana (Paullinia cupana) is a plant from the Amazon region with cultural importance. Despite its early ancestral use by indigenous tribes, the first reports regarding the benefits of guarana consumption for human health were published in the 19th century. Since then, the use of guarana seed in powder and extract forms has been studied for its diverse effects on human health, such as stimulating, anti-inflammatory, antioxidant, anticancer, hypocholesterolemic, and anti-obesity effects. These effects are attributed to the high content of bioactive compounds found in guarana seeds, especially methylxanthines and flavonoids. In fact, the Brazilian Food Supplement Law has officially acknowledged guarana as a source of bioactive compounds. The number and diversity of studies focused on guarana and human health are increasing; thus, organizing and describing the available evidence on guarana and its applications is necessary to provide a framework for future studies. In this narrative review, we have organized the available information regarding guarana and its potential effects on human health. Guarana produces unique fruits with great potential for human health applications. However, the available evidence lacks human studies and mechanistic investigations. Future studies should be designed considering its applicability to human health, including intake levels and toxicity studies.

Ilex paraguariensis extract as an alternative to pain medications

Pain is a common and distressing symptom of many diseases and its clinical treatment generally involves analgesics and anti-inflammatory drugs. This study evaluated the toxicity of Ilex paraguariensis A. St.-Hil. (Aquifoliaceae) aqueous extract (leaves, petioles and branches) and its performance in a nociceptive response. Hepatotoxicity, psycho-stimulant test and evaluation of enzyme markers for liver damage were also tested. Chromatographic analysis by UPLC-MS demonstrated a series of isomeric monocaffeoylquinic acids, isomers of dicaffeoylquinic acid, flavonol glycosides, and saponins. Phase I and II of nociception were obtained for meloxicam, dexamethasone and aqueous Ilex paraguariensis extract. Ilex paraguariensis extract concentration was negatively correlated (R = -0.887) with alanine aminotransferase (p < 0.05) in acetaminophen-induced hepatotoxicity test, indicating hepatoprotective activity of this extract. Ilex paraguariensis extract also presented analgesic properties equivalent to drugs that already have proven efficacy. Notably, the administration of multiple doses of Ilex paraguariensis extract was considered safe from the therapeutic point of view.

Evaluation of Antibacterial, Antineoplastic, and Immunomodulatory Activity of Paullinia cupana Seeds Crude Extract and Ethyl-Acetate Fraction

Paullinia cupana (Guarana) is a native plant of Amazon region that has very traditional importance. Its seeds are rich in bioactive compounds, including tannins, which exhibit relevant properties. Objective. This study aimed to evaluate antibacterial, antineoplastic, and immunomodulatory activity of P. cupana seeds crude extract (CE) and ethyl-acetate fraction (EAF). Methods. Antibacterial activity was evaluated by determination of minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Antineoplastic activity was evaluated by MTT assays in hepatocellular carcinoma (HepG2), breast adenocarcinoma (MCF-7), ductal carcinoma (T47-D), non-Hodgkin's B cell lymphoma (Toledo), T cell leukemia (Jukart), and Acute Leukemia (HL-60) cell lines. BALB/c mice splenocytes were treated to assess IFN-γ, IL-6, IL-17, and IL-10 levels by sandwich ELISA. Results. CE and EAF were not toxic to peripheral blood cells and splenocytes. CE and EAF fractions showed a bacteriostatic activity (MIC = 250 μg/mL) and presented IC₅₀ values of 70.25 μg/mL and 61.18 μg/mL in HL-60 leukemia cell line. All cytokines evaluated had their levels reduced after treatment, following dose-response model. Discussion and Conclusion. Different biological activities were observed for both CE and EAF, suggesting P. cupana as a source of bioactive substances, especially tannins that may be used for several diseases treatments.

Antidepressant-like effect of resveratrol: involvement of antioxidant effect and peripheral regulation on HPA axis

This study focused on exploring the antidepressant potential of resveratrol (RES) and its possible mechanisms of action. Cell injury was induced by corticosterone (CORT) and detected through cell viability and contents of lactate dehydrogenase (LDH) and malonaldehyde (MDA). A rat model of depression was established through 3weeks of consecutive chronic unpredictable mild stress (CUMS), and both the depression-like behaviors and the activity of the hypothalamic-pituitary-adrenal (HPA) axis were tested. Apart from the inhibitory effect on MDA production in vitro and in vivo, the results showed that RES (10(-10)mol/L to 10(-5)mol/L) could significantly increase the cell viability and decrease the LDH activity and that RES (15mg/kg) treatment could alleviate the depression-like behavior of CUMS rats, as indicated by increased sucrose preference and decreased immobility in forced swimming test and tail suspension test. Rats that received RES treatment displayed a reduction of serum CORT, suggesting that RES affected the hyperactivity of the HPA axis in CUMS rats. However, RES did not affect the expression of corticotropin-releasing hormone (CRH) mRNA in the hypothalamus of CUMS rats. In summary, our results demonstrated that in addition to its widely known antioxidant properties, RES also has antidepressant-like effects, and suggested that the underlying mechanism might involve its peripheral effect on the regulation of the HPA axis.

Guarana: revisiting a highly caffeinated plant from the Amazon

ETHNOPHARMACOLOGICAL RELEVANCE

Guarana (Paullinia cupana Kunth var. sorbilis (Mart.) Ducke) has been traditionally consumed by indigenous communities of the Amazon region. It is valued mainly for its stimulant property because of its high content of caffeine, which can be up to 6% in the seeds.

AIM OF THE REVIEW

The purpose of this review is to revisit this typically Brazilian plant, addressing economic considerations, the chemical makeup of the seeds and pharmacological properties so far investigated.

RESULTS

Guarana is primarily produced in the Brazilian states of Amazonas and Bahia, and approximately 70% of the production is used by the industry of soft and energy drinks. The other 30% becomes guarana powder for direct consumption in capsules or dilution in water, or it serves as a raw material for the pharmaceutical and cosmetics industries. In addition to its stimulant property, guarana has other therapeutic properties, which have aroused the interest of the scientific community.

CONCLUSION

This review shows that other guarana properties may be explored and how scarce are the studies regarding agronomic, plant pathology, physiology and breeding. So far, caffeine has been the main reason to study guarana and still will lead the researches because the demand for this alkaloid by food and pharmaceutical industry, and a strongly growing market related with beauty products. However, guarana has other components and there is great interest in studies designed to elucidate the effects of guarana's bioactive components and their potential pharmacological applications. Significant part of the guarana production in Brazil still comes from Indians tribes in the Amazon State, and any improvement in this plant, in any aspect, may propitiate a positive economic impact in their lives.

N-palmitoylethanolamide, an endocannabinoid, exhibits antidepressant effects in the forced swim test and the tail suspension test in mice

The antidepressant-like effects of N-palmitoylethanolamide (PEA), a putative endocannabinoid, was investigated in mice using the tail suspension test (TST) and the forced swimming test (FST). In TST, PEA (10, 20, and 40 mg/kg) produced a statistically significant reduction in immobility (50, 32, and 34%, respectively, vs. the control group), whereas fluoxetine (20 mg/kg) reduced immobility by 38%. In FST, PEA (5, 10, and 20 mg/kg) produced a statistically significant reduction in immobility (15, 21, and 36%, respectively), whereas fluoxetine (20 mg/kg) reduced immobility by 18%. Moreover, PEA (20 mg/kg) did not significantly change motor activity in a spontaneous behavioral test. In conclusion, PEA (dose range of 5-40 mg/kg) administered orally reduced immobility in TST and FST, comparable to the antidepressant effect of fluoxetine, and had no effect on spontaneous activity in mice.

Antinociceptive Activity of Trichilia catigua Hydroalcoholic Extract: New Evidence on Its Dopaminergic Effects

Trichilia catigua is a native plant of Brazil; its barks are used by some local pharmaceutical companies to prepare tonic drinks, such as Catuama. The present study was addressed to evaluate the effects of T. catigua hydroalcoholic extract in mouse nociception behavioral models, and to evaluate the possible mechanisms involved in its actions. Male Swiss mice were submitted to hot-plate, writhing and von Frey tests, after oral treatment with T. catigua extract (200 mg kg⁻¹, p.o.). The extract displayed antinociceptive effect in all three models. For characterization of the mechanisms involved in the antinociceptive action of the extract, the following pharmacological treatments were done: naloxone (2.5 mg kg⁻¹, s.c.), SR141716A (10 mg kg⁻¹, i.p.), SCH23390 (15 μg kg⁻¹, i.p.), sulpiride (50 mg kg⁻¹, i.p.), prazosin (1 mg kg⁻¹, i.p.), bicuculline (1 mg kg⁻¹, i.p.) or dl-p-chlorophenylalanine methyl ester (PCPA, 100 mg kg⁻¹, i.p.). In these experiments, the action of T. catigua extract was evaluated in the hot-plate test. The treatment with SCH23390 completely prevented the antinociceptive effect, while naloxone partially prevented it. The possible involvement of the dopaminergic system in the actions of T. catigua extract was substantiated by data showing the potentiation of apomorphine-induced hypothermia and by the prevention of haloperidol-induced catalepsy. In conclusion, the antinociceptive effects of T. catigua extract seem to be mainly associated with the activation of dopaminergic system and, to a lesser extent, through interaction with opioid pathway.

Evaluation of the effects of the herbal product Catuama in inflammatory and neuropathic models of nociception in rats

Here we evaluated the antinociceptive effects of the herbal drug Catuama in rat inflammatory and neuropathic models of pain, in order to assess some of the mechanisms involved in its actions. Catuama given orally, in both acute and chronic schedules of treatment, consistently inhibited the mechanical allodynia induced by the intraplantar (i.pl.) injection of complete Freund's adjuvant (CFA). The same treatment with Catuama failed to significantly affect CFA-caused thermal hyperalgesia. In addition, Catuama did not significantly modify the mechanical allodynia or hyperalgesia observed following the partial ligation of the sciatic nerve or the diabetic polyneuropathy, respectively. In another series of experiments, Catuama caused a striking reduction of the mechanical allodynia induced by LPS. Oral treatment with Catuama was not, however, effective in altering the production of the pro-inflammatory mediators IL-1beta, TNFalpha, PGE(2) or LTB(4) following i.pl. administration of LPS in the rat paw. Of high interest, the antinociceptive effects of Catuama in the LPS model were reversed significantly by the non-selective dopamine antagonist haloperidol, but not by serotonin methysergide or adrenergic yohimbine receptor antagonists. Our results indicate that the herbal drug Catuama diminishes inflammatory, but not neuropathic, nociceptive responses in rats, by mechanisms involving an interference with dopaminergic pathways. Catuama might represent a potential therapeutic tool for the management of persistent inflammatory pain.

The herbal drug Catuama reverts and prevents ventricular fibrillation in the isolated rabbit heart

INTRODUCTION

Catuama, an herbal drug very popular in Brazil, was tested on the reversion and prevention of ventricular fibrillation (VF) in the isolated rabbit heart.

MATERIALS AND METHODS

Catuama (a mixture of Trichilia catigua, Paullinia cupana, Ptychopetalum olacoides, and Zinziber officinalis) was perfused in the isolated perfused rabbit heart. Its effects on intraventricular conduction, heart rate, and monophasic action potential (MAP) duration were evaluated, and sustained VF was induced. The effects on reversion and reinduction of arrhythmia were observed, and new measures were taken in the hearts that reverted.

RESULTS

Catuama and T catigua reverted VF in all hearts, prevented reinduction, and prolonged intraventricular conduction. Catuama prolonged MAP phase 2. On the other hand, P cupana reverted VF in 3 of 5 hearts, but depressed automatism, prolonged MAP phase 3, and did not prevent reinduction.

DISCUSSION

Catuama reverted and prevented VF in this model. T catigua extract is probably the main agent responsible for the beneficial actions observed. Further studies are now in progress to clarify these actions.

Antidepressant-like effects of the traditional Chinese medicine kami-shoyo-san in rats

Kami-shoyo-san (KSS), a traditional Chinese medicine, has been used to treat patients with neuropsychiatric disorders. The aim of the present paper was to investigate whether KSS has antidepressant-like effects, and to assess its mechanism of action, using male Sprague-Dawley rats given 10-fold (KSS 10X) or 20-fold (KSS 20X) the typical human daily dosage. Immobility time was measured by the forced swimming test, and hippocampal neurogenesis was quantified under immobilization stress. Rats given KSS 20X, but not those given KSS 10X, had a significantly lower immobility time and improved neurogenesis in the hippocampus. These results suggest that KSS possesses an antidepressant-like effect at a behavioral and molecular level.

Brazilian plants as possible adaptogens: an ethnopharmacological survey of books edited in Brazil

In a survey, from Brazilian books, we searched plants that are in popular use for purposes resembling those of an adaptogen. This study focused on 24 books by authors from diverse regions in the country, resulting in a total of 1317 citations of uses related to a possible adaptogen effect from approximately 766 plants. Only species native to Brazil, cited in at least four books, were selected, resulting a total of 33 species, belonging to 24 families. Of these, four species have been studied previously in relation to effects that are considered as part of an adaptogen effect (anti-stress, memory enhancement, increased physical and/or sexual performance): Heteropterys aphrodisiaca (Malpighiaceae), Paullinia cupana (Sapindaceae), Ptychopetalum olacoides (Olacaceae), and Turnera diffusa (Turneraceae). Three others--Pfaffia glomerata, Pfaffia paniculata (Amaranthaceae), and Trichilia catigua (Meliaceae)--have also been the object of pharmacological studies that support their use as a possible adaptogen, but they are listed in less than four books. The overall results obtained in the present review of Brazilian folk literature reveals that Brazil is rich in plants with potential adaptogen-like effect, but lacks pharmacological studies (mostly clinical ones) to confirm these therapeutic properties.

Antidepressant-like effects of Trichilia catigua (Catuaba) extract: evidence for dopaminergic-mediated mechanisms

RATIONALE

Currently available therapy for depression treatment is often associated with several undesirable side effects, and it is effective only in a certain portion of the population. Therefore, the identification of alternative therapeutic tools for the treatment of depression is still needed.

OBJECTIVE

The present study analyzed the possible antidepressant-like effects of the Brazilian medicinal plant, Trichilia catigua, in rodents. Attempts were also made to investigate some of the possible mechanisms implicated in its actions.

METHODS

The antidepressant-like effects of T. catigua extract were assessed in two species of rodents (mice and rats) by means of in vivo (forced swimming test) and in vitro (monoamine reuptake and release in synaptosomal preparations) approaches.

RESULTS

Acute oral treatment with the extract of T. catigua produced antidepressant-like effects in the forced swimming model in both mice and rats. Anti-immobility actions of T. catigua extract in mice were significantly reversed by haloperidol or by chlorpromazine, but not by pimozide, ketanserin, spiroxatrine or p-chlorophenylalanine. In vitro, T. catigua extract concentration-dependently inhibited the uptake and increased the release of serotonin, and especially of dopamine, from rat brain synaptosomal preparations.

CONCLUSIONS

The present study provides convincing evidence for a dopamine-mediated antidepressant-like effect of the active principle(s) present in the hydroalcoholic extract of T. catigua in mice and rats when in vivo and in vitro strategies were employed. Therefore, a standardized T. catigua extract or its purified constituents could be of potential interest for the treatment of depressive disorders.

The effects of curcumin on depressive-like behaviors in mice

Curcuma longa is a major constituent of Xiaoyao-san, the traditional Chinese medicinal formula, which has been used effectively to treat depression-related diseases in China. There is no information available about the antidepressant activity of curcumin, the active component of curcuma longa. In the present study, we analyzed the effects of curcumin on depressive-like behaviors in mice, using two animal models of depression. Our results showed that curcumin treatment at 5 and 10 mg/kg (p.o.) significantly reduced the duration of immobility in both the tail suspension and forced swimming tests. These doses that affected the immobile response did not affect locomotor activity. In addition, the neurochemical assays showed that curcumin produced a marked increase of serotonin and noradrenaline levels at 10 mg/kg in both the frontal cortex and hippocampus. Dopamine levels were also increased in the frontal cortex and the striatum. Moreover, curcumin was found to inhibit monoamine oxidase activity in the mouse brain. These findings suggest that the antidepressant-like effects of curcumin may involve the central monoaminergic neurotransmitter systems.

Twenty-five years of research on medicinal plants in Latin America: a personal view

In this short article, I have discussed (on the base of the Web of Science data base search), the expressive progress of Latin American scientific production in peer review journals in the field of plants over the last 25 years. In addition, some effort has been made towards discussing the relevance of medicinal plants for the development of standardized phytomedicines with proof of quality, safety and efficacy, and a few examples of success have been briefly mentioned.

The tail suspension test as a model for assessing antidepressant activity: review of pharmacological and genetic studies in mice

Since its introduction almost 20 years ago, the tail suspension test has become one of the most widely used models for assessing antidepressant-like activity in mice. The test is based on the fact that animals subjected to the short-term, inescapable stress of being suspended by their tail, will develop an immobile posture. Various antidepressant medications reverse the immobility and promote the occurrence of escape-related behaviour. This review focuses on the utility this test as part of a research program aimed at understanding the mechanism of action of antidepressants. We discuss the inherent difficulties in modeling depression in rodents. We describe how the tail suspension differs from the closely related forced swim test. Further, we address some key issues associated with using the TST as a model of antidepressant action. We discuss issues regarding whether it satisfies criteria to be a valid model for assessing depression-related behavioural traits. We elaborate on the tests' ease of use, strain differences observed in the test and gender effects in the test. We focus on the utility of the test for genetic analysis. Furthermore, we discuss the concept of whether immobility maybe a behavioural trait relevant to depression. All of the available pharmacological data using the test in genetically modified mice is collated. Special attention is given to selective breeding programs such as the Rouen 'depressed' mice which have been bred for high and low immobility in the tail suspension test. We provide an extensive pooling of the pharmacological studies published to date using the test. Finally, we provide novel pharmacological validation of an automated system (Bioseb) for assessing immobility. Taken together, we conclude that the tail suspension test is a useful test for assessing the behavioural effects of antidepressant compounds and other pharmacological and genetic manipulations relevant to depression.