Preclinical evaluation of Trichilia catigua extracts on the central nervous system of mice

Trichilia catigua against Helicobacter pylori: An in vitro, molecular and in silico approach

Helicobacter pylori is a bacterium that is present in the stomach of about 50% of the global population and is associated with several gastric disorders, including cancer. Natural products with antimicrobial activity have been tested against H. pylori, among them Trichilia catigua (catuaba), which is widely distributed in Brazil. This study aimed to evaluate extracts of T. catigua bark against H. pylori via determination of the minimum inhibitory and bactericidal concentrations (MIC and MBC); evaluation of virulence factors by real-time PCR, synergism with standard antimicrobials and morphology by scanning electron microscopy and simulations of the mechanism of action by molecular docking. The ethyl acetate fraction provided the best results, with an MIC50 of 250 μg/mL and a 42.34% reduction in urease activity, along with reduced expression of the CagA and VacA genes, which encode for the main virulence factors. This fraction presented synergistic activity with clarithromycin, reducing the MIC of the drug by four-fold. Docking simulations suggested that the extracts inhibit fatty acid synthesis by the FAS-II system, causing damage to the cell membrane. Therefore, T. catigua extracts have potential as an adjuvant to treatment and are promising for the development of new anti-H. pylori drugs.

Delayed administration of Trichilia catigua A. Juss. Ethyl-acetate fraction after cerebral ischemia prevents spatial memory deficits, decreases oxidative stress, and impacts neural plasticity in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Trichilia catigua A. Juss (Meliaceae) is used in Brazilian folk medicine to alleviate fatigue and emotional stress and improve memory. Previous studies from our laboratory reported that an ethyl-acetate fraction (EAF) of T. catigua that was given before cerebral ischemia in vivo prevented memory loss and reduced oxidative stress and neuroinflammation. Despite the value of these findings of a neuroprotective effect of T. catigua, treatment that was given immediately before or immediately after ischemia limits its clinical relevance. Thus, unknown is whether T. catigua possesses a specific time window of efficacy (TWE) when administered postischemia.

AIM OF THE STUDY

Given continuity to previous studies, we investigated whether an EAF of T. catigua maintains its neuroprotective properties if treatment begins at different time windows of efficacy after ischemia. We also evaluated, for the first time, whether T. catigua possesses neuroplasticity/neurotrophic properties.

MATERIAL AND METHODS

Rats were subjected to transient global brain ischemia (TGCI) and then given a single dose of the EAF (400 mg/kg) or vehicle (1 ml/kg) orally 1, 4, or 6 h postischemia. The levels of protein PCG, GSH, and GSSG, and activity of SOD and CAT were assayed as markers of oxidative stress on the day after ischemia. In another experiment, naive rats underwent spatial learning training in a radial maze task and then subjected to TGCI. Delayed treatment with the EAF began 4 or 6 h later and continued for 7 days. Retrograde memory performance was assessed 10, 17, and 24 days postischemia. Afterward, brains were examined for neurodegeneration and neuronal dendritic morphology in the hippocampus and cerebral cortex. Another group received the EAF at 4 h of reperfusion, and 4 days later their brains were examined for GFAP and Iba-1 immunoreactivity. Lastly, ischemic rats received the EAF 4 h after ischemia and neural plasticity-related proteins, BDNF, SYN, PSD 95, and NeuN were measured in the hippocampus 7 and 14 days after ischemia.

RESULTS

A single EAF administration 1, 4, or 6 h postischemia alleviated oxidative stress that was caused by ischemia, expressed as a reduction of the amount of the PCG and GSSG, normalization of the GSH/GSSG ratio, and the restoration of SOD activity. Ischemia caused the persistent loss of memory (i.e., amnesia), an outcome that was consistently ameliorated by treatment with the EAF that was initiated 4 or 6 h postischemia. The 4 h delay in EAF treatment positively impacted dendritic morphology in neurons that survived ischemia. TGCI reduced BDNF, SYN, PSD-95, and NeuN protein levels in the hippocampus and cerebral cortex. The EAF normalized SYN and PSD-95 protein levels. Ischemia-induced neurodegeneration and glial cell activation were not prevented by EAF treatment.

CONCLUSION

The present study corroborates prior data that demonstrated the neuroprotective potential of T. catigua and extends these data by showing that the delayed administration of EAF postischemia effectively prevented memory impairment and decreased oxidative stress, dendritic deterioration, and synaptic protein loss within a TWE that ranged from 1 to 6 h. This specific TWE in preclinical research may have clinical relevance by suggesting the possible utility of this plant for the development of neuroprotective strategies in the setting of ischemic brain diseases. Another innovative finding of the present study was the possible neurotrophic/neuroplastic properties of T. catigua.

Evaluation of a multiple microemulsion from Trichilia catigua extract and the percutaneous penetration through skin by Phase-Resolved photoacoustic spectroscopy

Emulsion systems have been a breakthrough in cosmetic products, providing performance and effectiveness of products that use this technological strategy for drug delivery systems. In this sense, the microemulsion of the multiple emulsion W/O/W type containing a standardized extract of Trichilia catigua with high levels of polyphenols and antioxidants has great potential for cosmetic use. The aim of this study was to evaluate the formulations safety through the analysis of toxicity, comedogenicity, and histopathology in rabbits and apply the Phase-Resolved Photoacoustic Spectroscopy method to determine the formulation percutaneous penetration through the skin. The ex vivo experiments were performed in the ears of albino New Zealand rabbits treated twice a day for 14 days. The results of histological, hematological, and blood chemistry showed that the formulations are safe. Histopathological analysis showed no tissue reaction in any of the analyzed organs (liver and kidneys), confirming the absence of toxicity. Histological analysis showed that the formulations with extract of T. catigua demonstrated mild-moderately comedogenic and acanthosis compared to the control group. Inflammatory reactions, erythema, and desquamation were not observed in treated and controls animals. The phase-resolved photoacoustic spectroscopy method showed the penetration of the developed formulations throughout the rabbit's skin, identifying their absorption bands at the dermal side of the skin. In conclusion, the results of this study provide a step towards the application of the developed natural antioxidant encapsulated in a multiple microemulsion for skincare, concerned with the physical, chemical, and biological properties of the formulation.

In vitro and in vivo evaluations of antioxidative, anti-Alzheimer, antidiabetic and anticancer potentials of hydroponically and soil grown Lactuca sativa

BACKGROUND

Lactuca sativa is an edible plant commonly used by local communities to manage diabetes and stomach problems.

METHODS

This work aimed to investigate the anti-oxidant, anticancer, antidiabetic and Anti-Alzheimer effects of hydroponically (HyL) and soil-grown (SoL) Lactuca sativa. Streptozotocin-induced diabetes and AlCl3-induced Alzheimer's disease model was used to evaluate the medicinal effects of Lactuca sativa.

RESULTS

HyL showed significant activity in lipid peroxidation assay, DPPH and DNA protection assay, while SoL extract showed moderated activity, respectively. A similar activity response was quantified for α-glucosidase, α-amylase, acetylcholinesterase and butyrylcholinesterase inhibition assays. The cytotoxic potential of HyL and SoL extracts against MCF7, and HePG2 cancer cell lines exhibited significant activity. HyL and SoL showed a substantial decrease in blood glucose levels in streptozotocin-induced diabetic rats. Diabetes-related liver/kidney biomarkers and anti-oxidant enzyme trends moved toward normal after HyL and SoL treatment. In Anti-Alzheimer's based Morris water and elevated plus maze tests, HyL and SoL displayed memory-enhancing response and anti-anxiety behaviour, respectively. HPLC quantification of dopamine and serotonin revealed a moderate but significant (p<0.05) increase in the level of these neurotransmitters in HyL and SoL groups.

CONCLUSION

Overall, the study revealed that hydroponic Lactuca sativa possesses the therapeutic potential to treat diseases like Alzheimer's and diabetes.

Medicinal Plants in the Treatment of Depression: Evidence from Preclinical Studies

Medicinal plants and their extracts are natural remedies with enormous potential for treating various diseases, including depression and anxiety. In the case of depression, hundreds of plants have traditionally been used in folk medicine for generations. Different plant extracts and natural products have been analyzed as potential antidepressant agents with validated models to test for antidepressant-like effects in animals, although other complementary studies have also been employed. Most of these studies focus on the possible mediators implicated in these potential effects, with dopamine, serotonin, and noradrenaline being the principal neurotransmitters implicated, both through interference with receptors and with their metabolism by monoamino oxidases, as well as through neuro-endocrine and neuroprotective effects. There are approximately 650 reports of antidepressant-like medicinal plants in PubMed; 155 of them have been compiled in this review, with a relevant group yielding positive results. Saffron and turmeric are the most relevant species studied in both preclinical and clinical studies; St. John's wort or kava have also been tested extensively. To the best of our knowledge, no review to date has provided a comprehensive understanding of the biomolecular mechanisms of action of these herbs or of whether their potential effects could have real benefits. The purpose of this narrative review is to provide an update regarding medicinal plants from the year 2000 to the present to examine the therapeutic potential of these antidepressant-like plants in order to contribute to the development of new therapeutic methods to alleviate the tremendous burden that depression causes worldwide.

GABA and 5-HT Systems Are Involved in the Anxiolytic Effect of Gan-Mai-Da-Zao Decoction

The Gan-Mai-Da-Zao (GMDZ) decoction is one of the most famous Chinese medicine prescriptions to treat emotional diseases in China. Here we examined the anxiolytic-like effects of the GMDZ decoction in mice. The mice were orally administered with GMDZ decoction (1, 2, and 4 g/kg, respectively) for 7 days, diazepam (2 mg/kg, p.o.) and buspirone (5 mg/kg, p.o.) were used as positive controls. Then, elevated plus maze (EPM) test, light/dark box (LDB) test, and marble burying (MB) test, open field (OF) test and rota-rod test were performed. We found that GMDZ treatment (2 and 4 g/kg) significantly increased the percentage of open arm entries and time spent on the open arms in EPM as compared to the control. GMDZ treatment also significantly increased the time spent in the light box and the number of light box entries in LDB and reduced the number of marbles buried in MB. Similarly to those observed with diazepam and buspirone. In contrast, GMDZ did not affect the locomotor activity in the OF and motor coordination in the rota-rod test. Furthermore, the anxiolytic-like effects induced by GMDZ were inhibited by the γ-aminobutyric acid-A (GABA_A) receptor antagonist flumazenil and 5-hydroxytryptamine-1A (5-HT_1A) receptor antagonist WAY-100635. These results showed that GMDZ possesses anxiolytic-like effects in animal models, and its mechanism of action might be modulated by 5-HT_1A and GABA_A receptors.

Ethyl-acetate fraction of Trichilia catigua protects against oxidative stress and neuroinflammation after cerebral ischemia/reperfusion

ETHNOPHARMACOLOGICAL RELEVANCE

Trichilia catigua A. Juss (Meliaceae) preparations have been used in folk medicine to alleviate fatigue, stress, and improve memory. Antinociceptive, antiinflammatory, and in vitro neuroprotective effects have been observed in animals. Cerebral ischemia/reperfusion (I/R) leads to severe neuropsychological deficits that are largely associated with oxidative stress, inflammation and neurodegeneration. We reported previously that an ethyl-acetate fraction (EAF) of T. catigua reduced brain ischemia-induced learning and memory impairments in the absence of histological protection.

AIM OF THE STUDY

Continuing those studies, here we aimed to investigate the antioxidant and antiinflammatory properties of T. catigua in an in vivo model of I/R.

MATERIAL AND METHODS

Rats were subjected to 15 min of brain ischemia (4-VO model) followed by up to 15 days of reperfusion. Vehicle was given by gavage 30 min before ischemia and at 1 h of reperfusion. In a first experiment, brain ischemia-induced changes in oxidative stress markers, i.e., reduced glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and protein carbonyl groups (PCGs) were measured on days 1, 3, and 5 post-ischemia. Similar time course analysis was done for neuroinflammation markers, i.e., microglia (OX42 immunorreactivity) and astrocytes (GFAP immunorreactivity), in the hippocampus. In a second experiment, the time points at which these markers of oxidative stress and neuroinflammation peaked were used to test the effects of T. catigua (400 mg/kg, p.o.).

RESULTS

Oxidative stress markers peaked on day 1 post-ischemia. GSH decreased (-23.2%) while GSSG increased (+ 71.1%), which yielded a significant reduction in the GSH/GSSG ratio (-39.1%). The activity of CAT was largely reduced by ischemia (-54.6% to -65.1%), while the concentration of PCG almost doubled in the brain of ischemic rats (+99.10%) in comparison to sham. Treatment with the EAF of T. catigua normalized these changes in oxidative markers to the control levels (GSH: +27.5%; GSSG: -23.8%; GSH/GSSG: +44.6%; PCG: -80.3%). In the hippocampus, neuroinflammation markers peaked on day 5 post-ischemia, with microglial and astrocytic responses increasing to 54.8% and 37.1%, respectively. The elevation in glial cells response was completely prevented by EAF.

CONCLUSION

These results demonstrate that T. catigua has both antioxidant and antiinflammatory activities after transient global cerebral ischemia in rats, which may contribute to the previously reported memory protective effect of T. catigua.

Antioxidant, anticholinesterase and antifatigue effects of Trichilia catigua (catuaba)

BACKGROUND

Trichilia catigua A. Juss. (Meliaceae) is a species known as catuaba and used in folk medicine for the treatment of fatigue, stress, impotence and memory deficit. The main phytochemical compounds identified in the barks of T. catigua are flavalignans, flavan-3-ols and flavonoids which are associated with its antioxidant activity. Pre-clinical studies with T. catigua extracts have identified many pharmacological properties, such as anti-inflammatory, antidepressant, antinociceptive, pro-memory and neuroprotective against ischemia and oxidative stress. This study was designed in order to compare the chemical composition and in vitro antioxidant and anticholinesterase activity of four different polarity extracts and selected the one most active for in vivo studies in rodent models of stress, fatigue and memory.

METHODS

Hexane, chloroform, hydroalcoholic and aqueous extracts from bark of Trichilia catigua were analyzed by RPHPLC-DAD-ESI-MS/MS. Antioxidant activity was assessed by 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay and acetylcholinesterase inhibition by Ellman's modified method. In vivo studies (stress, fatigue and memory) were carried out with adult male mice and rats treated with hydroalcoholic extract in doses of 25-300 mg/kg (p.o.).

RESULTS

We confirmed the presence of cinchonain IIa, Ia and Ib, as main constituents in the four extracts, while procyanidins were detected only in hydroalcoholic extract. Antioxidant and anticholinesterase activity were observed for all extracts, with most potent activity found on the hydroalcoholic extract (EC50 = 43 μg/mL and IC50 = 142 μg/mL for DPPH scavenger and acetylcholinesterase inhibition, respectively). The treatment of laboratory animals with hydroalcoholic extract did not protect rats from cold immobilization stress and did not prevent the scopolamine-induced amnesia in mice. However, the treatment of mice with the hydroalcoholic extract partially reduced the fatigue induced by treadmill, since the highest dose increased the spontaneous locomotor activity and reduced the deficit on grip strength after the forced exercise (p < 0.05), in some observation times.

CONCLUSIONS

These data suggest the hydroalcoholic extract as the most suitable for plant extraction and partially support the folk use of T. catigua as antifatigue drug. . Trichilia catigua hydroalcoholic extract exhibits antioxidant and anticholinesterase activity in vitro and reduces the fatigue induced by forced exercise.

In vitro multimodal-effect of Trichilia catigua A. Juss. (Meliaceae) bark aqueous extract in CNS targets

ETHNOPHARMACOLOGICAL RELEVANCE

The bark of Trichilia catigua A. Juss. (Meliaceae), popularly known as "big catuaba", is traditionally used in Brazilian folk medicine for its neuroactive potential as memory stimulant, and antinociceptive and antidepressant effects.

AIM OF THE STUDY

To study the aqueous extract of T. catigua bark as dual inhibitor of monoamine oxidase A (MAO-A) and acetylcholinesterase (AChE). To explore its antioxidant potential through interaction with xanthine/xanthine oxidase (X/XO) pathway, and to attempt a relationship between its phenolic profile and effects displayed.

MATERIALS AND METHODS

Phenolic profiling was achieved by HPLC-DAD-ESI/MSⁿ and UPLC-ESI-QTOF-MS analyses. The capacity to inhibit hMAO-A was assessed in vitro, as was that for AChE, evaluated in rat brain homogenates. The direct inhibition of the X/XO pathway and the scavenging of superoxide anion radical were the selected in vitro models to explore the antioxidant potential. The cytotoxic effects were assayed in the human neuronal SH-SY5Y cells by MTT reduction, after direct exposure (24h).

RESULTS

Twenty-six compounds were identified and quantified (551.02 ± 37.61mg/g of lyophilized extract). The phenylpropanoid substituted flavan-3-ols were the most representative compounds (~81% of quantified mass). The extract inhibited hMAO activity in a concentration-dependent manner (IC₅₀ = 121.06 ± 2.13μg/mL). A mixed model of inhibition of AChE activity was observed, reflected by the pronounced increase of Km values and a more discreet effect over the Vmax parameters, calculated from Michaelis-Menten fitted equations. In addition, it was demonstrated that the extract directly inhibits the X/XO pathway (IC₅₀ = 121.06 ± 2.13μg/mL) and also imbalances the oxidative stress acting as superoxide anion radical scavenger (EC₅₀ = 104.42 ± 10.67μg/mL), an oxidative by-product of this reaction. All these neuroprotective and neurotrophic effects were displayed within the non-toxic range of concentrations (0.063-0.500μg/mL) in SH-SY5Y cells.

CONCLUSIONS

Our results validate the traditional use of T. catigua bark for its neuroactive and neuroprotective potential. A novel approach upon its application towards the management of neurodegenerative and related symptomatology was likewise demonstrated.

Ethyl-acetate fraction of Trichilia catigua restores long-term retrograde memory and reduces oxidative stress and inflammation after global cerebral ischemia in rats

We originally reported that an ethyl-acetate fraction (EAF) of Trichilia catigua prevented the impairment of water maze learning and hippocampal neurodegeneration after transient global cerebral (TGCI) in mice. We extended that previous study by evaluating whether T. catigua (i) prevents the loss of long-term retrograde memory assessed in the aversive radial maze (AvRM), (ii) confers hippocampal and cortical neuroprotection, and (iii) mitigates oxidative stress and neuroinflammation in rats that are subjected to the four vessel occlusion (4-VO) model of TGCI. In the first experiment, naive rats were trained in the AvRM and then subjected to TGCI. The EAF was administered orally 30min before and 1h after TGCI, and administration continued once per day for 7days post-ischemia. In the second experiment, the EAF was administered 30min before and 1h after TGCI, and protein carbonylation and myeloperoxidase (MPO) activity were assayed 24h and 5days later, respectively. Retrograde memory performance was assessed 8, 15, and 21days post-ischemia. Ischemia caused persistent retrograde amnesia, and this effect was prevented by T. catigua. This memory protection (or preservation) persisted even after the treatment was discontinued, despite the absence of histological neuroprotection. Protein carbonyl group content and MPO activity increased around 43% and 100%, respectively, after TGCI, which were abolished by the EAF of T. catigua. The administration of EAF did not coincide with the days of memory testing. The data indicate that antioxidant and/or antiinflammatory actions in the early phase of ischemia/reperfusion contribute to the long-term antiamnesic effect of T. catigua.

Capillary Electrophoresis as Tool for Diastereomeric Separation in a Trichilia catigua Fraction

INTRODUCTION

The tree Trichilia catigua, popularly known as "catuaba", shows several biological activities and has emerged as a potential source of new drugs. Considering that more than 10 species are known under the same popular name, regulatory agencies require more rigorous quality control of this medicinal plant.

OBJECTIVE

To develop and validate a methodology using capillary electrophoresis (CE) with ultraviolet (UV) detection for analysing polyphenols in the ethyl-acetate fraction (EAF) of Trichilia catigua.

METHODOLOGY

Different electrophoretic conditions (such as wavelength of UV detection, voltage, buffer concentration and pH, cyclodextrin type and concentration) were investigated. After optimisation, borate buffer 80 mmol/L at pH 8.80 with 2-hydroxypropyl-β-cyclodextrin 10 mmol/L was selected as background electrolyte. A voltage reduction was used to improve the separation of a diastereomeric pair of cinchonains.

RESULTS

The method proved to be simple, sensitive, accurate, linear, precise and reproducible. For the first time in natural products analysis, a voltage reduction and hydroxypropyl-β-cyclodextrin were used to improve the separation of diastereomeric pairs. Until now, this is the only described methodology able to separate catechin, epicatechin, cinchonains Ia, Ib, IIa, and IIb from Trichilia catigua samples on the same run in less than 12 min. When compared to the high performance liquid chromatography with photo-diode array detection (HPLC-PDA) method previously developed by our research group, the CE method was more efficient, faster, less expensive and less polluting.

CONCLUSION

Our results demonstrate that this method could be employed in a quality-control laboratory for the quantification of polyphenols in EAF of Trichilia catigua. Copyright © 2016 John Wiley & Sons, Ltd.

Trichilia catigua ethyl-acetate fraction protects against cognitive impairments and hippocampal cell death induced by bilateral common carotid occlusion in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Trichilia catigua preparations have antinociceptive, antiinflammatory, and neuroprotective activity. Recently, a neuroprotective role for T. catigua was proposed using an in vitro model of ischemia-reperfusion in rat hippocampal slices. The aim of the present study was to evaluate the effects of an ethyl-acetate fraction (EAF) of T. catigua, which has potent antioxidant activity, in mice subjected to an in vivo model of cerebral ischemia.

MATERIAL AND METHODS

Male Swiss mice were subject to the bilateral common carotid occlusion (BCCAO) model of cerebral ischemia. The animals were orally administered the T. catigua EAF (200, 400, or 800 mg/kg) 30 min before and once per day for 7 days after BCCAO. Histological and behavioral outcomes were assessed using Nissl staining and the Morris water maze test of cognition, respectively.

RESULTS

Mice that were subjected to BCCAO exhibited cognitive impairments in the Morris water maze. The spatial cognitive deficits were counteracted by T. catigua EAF administration (200-800 mg/kg). The T. catigua EAF significantly increased the number of intact-appearing Nissl-stained cells in the hippocampus in BCCAO mice.

CONCLUSIONS

These results show that the T. catigua EAF promoted functional recovery, decreased the delayed hippocampal cell loss, and mitigated the ongoing neurodegenerative processes induced by BCCAO in mice.

The exposure to Trichilia catigua (catuaba) crude extract impairs fertility of adult female rats but does not cause reproductive damage to male offspring

ETHNOPHARMACOLOGICAL RELEVANCE

Trichilia catigua is broadly used in folk medicine due to its mental and physical tonic activities and stimulant effects. In animal models, its antidepressant-like effects have been associated with the dopaminergic (DA) system modulation, which has an important role on maternal behavior and male offspring reproductive development.

AIM OF THE STUDY

Since little is known about the adverse effects of the exposure to T. catigua crude extract (CAT) in rats, specially regarding maternal homeostasis and offspring development, the aim of the present study was to evaluate whether CAT exposure may influence maternal toxicity parameters and behavior or disrupt male offspring physical and reproductive development.

MATERIAL AND METHODS

Dams were treated daily (by gavage) with 400mg/kg of CAT or vehicle (control=CTR) throughout pregnancy and lactation. Fertility and maternal behavior tests were conducted in dams. Male offspring reproductive and behavioral parameters were analyzed.

RESULTS

Dams exposed to CAT showed increased pre- and post-implantation losses rates when compared to CTR group. No significant changes regarding maternal behavior or male offspring parameters were observed.

CONCLUSION

In conclusion, maternal exposure to CAT interfered with implantation during the initial phases of pregnancy but did not induce changes on maternal behavior or male offspring reproductive and behavioral parameters.

Informal Trade of Psychoactive Herbal Products in the City of Diadema, SP, Brazil: Quality and Potential Risks

The present study aimed to assess the quality and risks involved in the consumption of psychoactive herbal products (PHs) that are available through informal commerce in the city of Diadema, SP, Brazil. Methods of ethnography were used to conduct the fieldwork during which four dealers were selected to record the collection, handling, packaging, types of PHs marketed, and their therapeutic purposes. In addition, lots of the PHs selected were purchased from the dealers and analyzed using microbiology and pharmacognosy techniques. 217 PHs were recorded and categorized into two main groups: stimulants (67%) and depressants (27%) of the central nervous system; sixteen of them were selected, and their 52 lots were acquired. The deficiencies observed in handling and packaging these lots by dealers were confirmed by microbiological analysis; 80.8% of them presented risk according to the indicators defined by the Brazilian Pharmacopoeia. The pharmacognostic analysis confirmed the authenticity of only 9 to 16 PHs analyzed. In addition, descriptions of contraindications, adverse reactions, and drug interactions were found in the literature for the PHs. The results of this study allow the observation of the priorities for the sanitary adequacy of the popular trade of herbs.

Subchronic administration of Trichilia catigua ethyl-acetate fraction promotes antidepressant-like effects and increases hippocampal cell proliferation in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Trichilia catigua preparations have been popularly used in Brazil as a tonic for the treatment of fatigue, stress, impotence, and memory deficits. We recently demonstrated an antidepressant-like effect of acute administration of the Trichilia catigua ethyl-acetate fraction (EAF) in mice. The aim of the present study was to evaluate whether subchronic Trichilia catigua EAF administration maintains its antidepressant-like effects and whether these effects are related to hippocampal neurogenesis.

MATERIAL AND METHODS

Trichilia catigua EAF (200 and 400mg/kg) was orally administered to mice for 14 day. The animals were tested in the forced swim test (FST) or tail suspension test (TST). After behavioral testing, the animals received bromodeoxyuridine (BrdU; 200mg/kg, i.p.) and were euthanized 24h, 7 day, or 15 day later. The brains were assayed for BrdU and doublecortin (DCX) immunohistochemistry to detect cell proliferation/survival and neurogenesis, respectively.

RESULTS

Subchronic administration of 400mg/kg Trichilia catigua EAF promoted antidepressant-like effects in mice in both the FST and TST. The antidepressant-like effect was accompanied by an increase in cell proliferation in the dentate gyrus (DG) of the hippocampus 24h after the treatments were discontinued. This proliferative effect, however, did not influence cell survival or neurogenesis because no change in the number of BrdU- or DCX-positive cells was detected 7 or 15 day after the last EAF administration compared with controls.

CONCLUSIONS

Trichilia catigua EAF produced antidepressant-like effects and induced hippocampal cell proliferation in mice. The results contribute information on the pharmacological and molecular mechanisms involved in the antidepressant-like effect of Trichilia catigua EAF.