Anxiolytic Effects of a Semipurified Constituent of Guaraná Seeds on Rats in the Elevated T-Maze Test

• Abstract
• Abbreviations
• Introduction
• Materials and Methods
• Plant material
• Extraction and fractionation
• Drugs
• Animals
• Apparatus
• Behavioral tests
• Treatment
• Statistical analysis
• Results
• Discussion
• Acknowledgements
• References

Abstract

The objective of this study was to investigate the effects of chronic administration of a semi-purified extract (Purified Extract A – PEA; 4, 8, or 16 mg/kg) of Paullinia cupana (guaraná) seeds on rats submitted to the elevated T-maze (ETM) model of generalized anxiety and panic disorders. The selective serotonin (5-HT) reuptake inhibitor (SSRI) paroxetine (PAR; 3 mg/kg), was used as a positive control. To evaluate possible serotonergic and dopaminergic neurotransmission involvement in the action of PEA during the ETM test, ineffective doses of metergoline (MET; 5-HT_2A/2C antagonist receptor) or sulpiride (SUL; dopaminergic receptor antagonist) were acutely administered together with the PEA. The locomotion of the rats was assessed in a circular arena following each drug treatment. Both PEA (8 and 16 mg/kg) and PAR (3 mg/kg) increased one-way escape latencies from the open arm of the ETM, indicating a panicolytic effect compared to the control group. MET, in higher doses (1, 2 or 3 mg/kg), produced a panicolytic effect in the ETM test, whereas SUL did not (10, 20 or 40 mg/kg). The panicolytic effect produced by PEA (8 mg/kg) was blocked by both MET (2 mg/kg) and SUL (20 mg/kg), whereas the panicolytic effect produced by PAR (3 mg/kg) was blocked only by MET (2 mg/kg). These results show that chronic treatment with PEA produces a panicolytic effect during the ETM test, and that the dopaminergic and the serotonergic neurotransmission systems are involved in this effect.

Abbreviations

EBPC: crude lyophilized extract

ETM: elevated T maze

5-HT: serotonin

MAO: monoaminoxidase

MET: metergoline

PAR: paroxetine

PEA: purified extract A

RMANOVA: repeated-measure analysis of variance

SSRI: selective serotonin reuptake inhibitor

VEH: vehicle

Introduction

Anxiety disorders, such as generalized anxiety disorder, panic disorder, obsessive-compulsive disorder and phobias, are the most common psychiatric conditions [1]. Although usually temporary and moderate, these disorders can be severe and resistant to treatment, resulting in high costs for public health systems [2], [3]. They can have a strong negative impact on quality of life and lead to reduced professional performance, lost work time, difficulties in adapting to new situations, problems in interpersonal relationships [4], marital problems and financial difficulties [5].

Although the available pharmacological treatments for these disorders are effective, they have many limitations. Selective serotonin reuptake inhibitor (SSRI) antidepressants produce an initial worsening of anxiety symptoms, especially in panic disorders [6], and resistance occurs in approximately 30 % of patients [7], while benzodiazepines have a high incidence of dependency [8]. For these reasons, and because of their prevalence and the high degree of suffering they cause, anxiety disorders are among the most common reasons for searching for complementary therapies [9] and self-medication with medicinal herbs [10].

It is estimated that Brazil has the greatest plant biodiversity in the world [11], and Paullinia cupana (H. B. K. var. sorbilis [Mart.] Ducke) is just one of many potentially useful plants available. It belongs to the Sapindaceae family and is popularly known as guaraná. It is grown mainly in the central Amazon basin [12], and its pharmacological actions have been a target of interest for pharmaceutical laboratories for some time. Its seed contains high concentrations of xanthines (3.0–6.0 %), which contain 1,3-caffeine (trimethylxanthine) and traces of theophylline and theobromine, as well as high concentrations of polyphenols and saponins (7 %) which, in turn, contain catechins, epicatechins, and other condensed tannins [12], [13].

The wide use of extracts from guaraná seeds and roots is due to their stimulative effects on the central nervous system [13]. The extracts are used as anorectics, nootropics (producing improvements in cognitive ability and memory) and aphrodisiacs [12], [14], [15]. Various pre-clinical and clinical studies have confirmed that the use of guaraná seed extract can improve memory performance [15], [16].

A semi-purified fraction obtained from guaraná seed extract, called Purified Extract A (PEA; State University of Maringá, patent pending PI0006638-9) was found to improve performance and memory speed [17], and produced antidepressant-like effects in rats [18]. These effects were similar to those produced by the tricyclic antidepressant imipramine, but were different to those produced by equipotent doses of caffeine, suggesting that other active substances present in the extract and fraction were responsible for the effects. Additionally, clinical studies have shown that guaraná can improve the mood of healthy volunteers [19].

In the light of this, the objective of this study was to assess the anxiolytic and panicolytic effects of PEA on rats subjected to the elevated T-maze (ETM) test. In order to understand the mechanisms involved in the effects produced by PEA, serotonergic (metergoline; MET) and dopaminergic (sulpiride; SUL) antagonists were used in combination with PEA in the ETM test.

Materials and Methods

Plant material

The Paullinia cupana seeds (var. sorbilis [Mart.] Ducke [Sapindaceae]) were collected in the Alta Floresta region of the State of Mato Grosso, Brazil. They were then dried, identified and pulverized in a hammer mill (Tigre ASN-5). Identification was carried out by Dr. Cássia Mônica Sakuragui. A voucher plant specimen (#HUEM9065) was deposited in the herbarium of the State University of Maringá.

Extraction and fractionation

The extract was prepared from the ground guaraná seeds (1000 g) by turbolysis using an acetone : water (7 : 3; v/v) extractor solution. After removal of the organic solvent, the remaining solid material was lyophilized (EBPC – crude lyophilized extract). Then, 158 g of the semipurified lyophilized extract was partitioned with ethyl acetate (10 ×, 5 L), resulting in an ethyl acetate fraction (PEA: 44 g; patent pending PI0006638-9). The PEA was solubilized in distilled water immediately before administration. Spectrophotometric analysis detected caffeine and tannin proportions of 34.95 ± 0.99 % (RSD% = 2.83) and 17.53 ± 0.37 % (RSD% = 2.09), respectively, in the PEA [20].

The PEA fraction was extracted using a solid-phase cartridge (Phenomenex® Strata C18-E) in a methanol : water (10 : 90; v/v) solution to 80 µg/mL. The extracts were filtered (0.45 µm; Millipore®) prior to injection in HPLC. The experiments were performed in a Thermo® Finnigan Surveyor HPLC system coupled to a Thermo® UV/VIS Plus detector with an injecting valve fitted with a 20 µL loop. Data acquisition was performed using ChromQuest® 4.2 software. A Phenomenex® Synergi Polar – RP 80A (250 × 460 mm, 4 µm) and guard column (Analytical Guard Cartridge System KJO-4282) were used in all experiments. Water was obtained using a Milli-Q Gradient® system. The mobile phase consisted of Phase A: a mixture from methanol : acetonitrile (25 : 75; v/v) containing 0.05 % trifluoroacetic acid (TFA) and Phase B: water with 0.05 % TFA previously filtered through a 0.45 µm filter (Millipore®). All solvents were degassed using an ultrasonic bath. The gradient system consisted of 0 min, 20 % Phase A; 20 min, 26 % Phase A, 0.9 mL/min flow rate, 210 nm UV detection at room temperature. Reference standards (catechin, 99 % purity [Sigma]; epicatechin, 95 % purity [Sigma] and caffeine, 99 % purity [Sigma]) were used to identify the major components in the PEA. Quantification was carried out by considering the peak of each component as a proportion of the total area of all peaks.

Drugs

PEA, PAR (positive control; IPCA Laborat; 99.1 %), MET (Sigma; 5-HT_2A/2C receptor antagonist; ≥ 98 %) and (−) SUL (Sigma; non-selective dopaminergic receptor antagonist; ≥ 98 %) were solubilized in saline solution (0.9 % NaCl) containing 2 % Tween 80. The control group was treated with only the vehicle (VEH; 0.9 % NaCl plus 2 % Tween 80).

Animals

Male Wistar rats (55 days old, 230–250 g) housed 5 per cage at constant room temperature (22–23 °C) under a 12-h light-dark cycle with free access to food and water were used in the experiments. The experiments were performed between 13:00 h and 18:00 h. The experimental procedures adopted were approved by the State University of Maringá Ethics Committee (053/2008), and followed the recommended guidelines for Biomedical Research Involving Animals (CIMS), Geneva, 1985.

Apparatus

The ETM was constructed of wood and had three arms of equal dimensions (50 × 12 cm). One arm, enclosed by 40-cm-high walls, was perpendicular to two opposed open arms. To prevent the animals from falling off, the open arms were surrounded by a 1-cm-high Plexiglas rim. The entire apparatus was positioned 50 cm above the floor. Locomotion was measured in a circular wooden arena, 70 cm in diameter, with 30 cm high walls. Luminosity at the level of the maze arms and at the center of the circular arena was 60 lux.

Behavioral tests

One day before the test, each animal was pre-exposed to one of the open arms of the ETM for 30 min. A wooden barrier mounted between the central area of the maze and the proximal end of the arm isolated it from the rest of the ETM. It has been shown that such pre-exposure to the open arm makes the escape task a more sensitive measure of the effects of antipanic drugs, as it shortens the withdrawal latencies from the open arm during the test [21].

The ETM test was initiated by the inhibitory avoidance task. For this, each animal was placed at the distal end of the enclosed arm of the ETM facing the intersection. The time taken by the rat to leave this arm with all four paws was recorded (baseline latency). This measurement was repeated in two subsequent trials (avoidance 1 and 2) at 30-s intervals. Thirty seconds after the avoidance trials, the rats were placed at the end of the open arm they had been previously exposed to, and the latency to leave this arm with all four paws was recorded in three consecutive trials (one-way escape 1, 2, and 3) at 30-s intervals. A cut-off time of 300 s was established for the avoidance and escape latencies. Thirty seconds after being tested in the ETM, each animal was placed in the circular arena for 5 min to evaluate their locomotion. The total distance traveled was analyzed by a video tracking system (Ethovision).

Treatment

To determine the dose-response curve of PEA, the animals were treated for 24 days with PAR (3 mg/kg), PEA (4, 8, and 16 mg/kg) or VEH by gavage (i. g.). On the 23rd day, the pretests were carried out, in which the animals were confined in one of the open arms of the ETM for 30 min, and they then received their i. g. treatment (drugs or VEH) after the pretest. On the 24th day of treatment, the animals were acutely pretreated with the VEH by intraperitoneal (i. p.) route and then treated with PAR, PEA or VEH (i. g.) 5 min later. The animals were submitted to the behavioral tests 60 min after this last treatment.

To determine the dose-response curves of the antagonists MET (1, 2, or 3 mg/kg) and SUL (10, 20, or 40 mg/kg), the animals were treated for 24 days with the VEH (i. g.). On the 23rd day, the pretests were performed as described above, with the animals receiving their VEH (i. g.) treatment after the tests. Only on the 24th day of treatment were the animals acutely pretreated with MET, SUL or VEH (i. p.), and then treated with VEH (i. g.) 5 min later. They were submitted to the behavioral tests 60 min after the last treatment.

In the studies evaluating the association of the antagonists (MET or SUL) with PEA or PAR, the animals were treated for 24 days with PAR (3 mg/kg), PEA (8 mg/kg) or VEH (i. g.). On the 23rd day of treatment, the pretests were performed as described above, with the animals receiving their treatments (drugs or VEH; i. g.) after the tests. On the 24th day of treatment, the animals were acutely pretreated with the VEH or antagonists (i. p.), and then treated with PAR (3 mg/kg), PEA (8 mg/kg) or VEH (i. g.) 5 min later. They were submitted to the behavioral tests 60 min after the last treatment.

Statistical analysis

Repeated-measure analyses of variance (RMANOVA) were used to analyze both avoidance and escape data. The systemic treatments were considered as the independent factors and the tests (baseline, avoidance 1 & 2 and escape 1–3) as the repeated measures. When appropriate, one-way ANOVAs followed by the post-hoc Duncan's multiple comparison test, were used. Locomotion data were analyzed by one-way ANOVAs followed by the post-hoc Duncan's multiple comparison test. Differences between groups were considered significant if p < 0.05.

Results

A chromatogram of an 80 µg/mL extract of PEA can be seen in [Fig. 1]. The results indicate that the principal components of the fraction are (approximately): 27 % catechin (peak 1), 38 % epicatechin (peak 2) and 27 % caffeine (peak 3).

[Fig. 2] and [Table 1] show the effects of acute administration of the VEH (i. p.) in rats chronically treated (i. g.) with the VEH (control group), PAR (3 mg/kg), or PEA (4, 8, or 16 mg/kg) in the ETM and circular arena tests, respectively. The RMANOVA for the inhibitory avoidance test showed a significant main effect on the trials (F_[2.120] = 68.37, p < 0.001), but no significant effect on the treatment (F_[4.60] = 0.68, p = 0.60) or on the treatment × trial interaction (F_[8.120] = 1.32, p = 0.23). For the escape test, the RMANOVA showed a significant main effect on treatment (F_[4.60] = 5.79, p < 0.001), but no significant effect on the trials (F_[2.120] = 1.85, p = 0.16) or on treatment × trial interaction (F_[8.120] = 0.91, p = 0.51). Post-hoc comparisons showed that PEA (8 and 16 mg/kg) increased escape 2 (* p < 0.05) and 3 (** p < 0.01) latencies, respectively, and that PAR (3.0 mg/kg) significantly increased escape 2 (** p < 0.01) and 3 (* p < 0.05) latencies compared to the control group, indicating a panicolytic effect. A one-way ANOVA did not show significant differences in distances traveled under the different treatments compared to the control group ([Table 1]).

[Fig. 3 A] and [C] shows the results observed in the ETM test after acute administration (i. p.) of the VEH or MET (1, 2, or 3 mg/kg) in rats chronically treated with the VEH (i. g.). The RMANOVA for the inhibitory avoidance test ([Fig. 3 A]) showed a significant main effect on the trials (F_[2.54] = 17.53, p < 0.001) but no significant effect on treatment (F_[3.27] = 1.07, p = 0.37) or on treatment × trial interaction (F_[6.54] = 0.93, p = 0.48). For the escape test ([Fig. 3 C]), the RMANOVA showed a significant main effect on treatment (F_[3.27] = 4.01, p < 0.05), but no significant effect on the trials (F_[2.54] = 0.38, p = 0.68) or on treatment × trial interaction (F_[6.54] = 0.63, p = 0.70). Post-hoc comparisons showed that MET (3.0 mg/kg) significantly increased the escape 1 (** p < 0.01) and 3 (* p < 0.05) latencies compared to the control group, indicating a panicolytic effect.

[Fig. 3 B] and [D] shows the results observed in the ETM test for acute administration (i. p.) of the VEH or SUL (10, 20, and 40 mg/kg) in rats chronically treated with the VEH (i. g.). The RMANOVA for the inhibitory avoidance test ([Fig. 3 B]) showed a significant main effect on the trials (F_[2.56] = 28.93, p < 0.001) but no significant effect on treatment (F_[3.28] = 0.75, p = 0.52) or on treatment × trial interaction (F_[6.56] = 1.11, p = 0.36). For the escape test ([Fig. 3 D]), the RMANOVA showed no significant effect on the trials (F_[2.56] = 2.73, p = 0.07), treatment (F_[3.28] = 0.92, p = 0.43) or treatment X trial interaction (F_[6.56] = 0.14, p = 0.98]. A one-way ANOVA did not show significant differences in distance traveled under these different treatments compared to the control group ([Table 2]).

[Fig. 4 A] and [C] shows the results observed in the ETM test for the combination (acute, i. p.) of the VEH and MET (2 mg/kg) in rats chronically treated (i. g.) with the VEH, PAR (3 mg/kg) or PEA (8 mg/kg). For the inhibitory avoidance test ([Fig. 4 A]), the RMANOVA showed a significant main effect on the trials (F_[2.116] = 32.85, p < 0.001), but no significant effect on treatment (F_[5.58] = 1.16, p = 0.34) or on treatment × trial interaction (F_[10.116] = 1.00, p = 0.43). For the escape test ([Fig. 4 C]), the RMANOVA showed a significant main effect on treatment (F_[5.58] = 7.20, p < 0.001), but no significant effect on the trials (F_[2.116] = 1.37, p = 0.25) or on the treatment X trial interaction (F_[10.116] = 1.07, p = 0.38). Post-hoc comparisons showed that PAR (3.0 mg/kg) significantly increased escape 1 (* p < 0.05), 2 (** p < 0.01) and 3 (** p < 0.01) latencies, and PEA (8 mg/kg) increased escape 2 (** p < 0.01) and 3 (** p < 0.01) latencies compared to the control group, indicating a panicolytic effect. MET (2 mg/kg) blocked the panicolytic effect produced by PAR (3 mg/kg), as can be seen by the significant differences in escape 1, 2 (^# p < 0.05) and 3 (^# p = 0.05) latencies between the MET + PAR and the VEH + PAR groups. Furthermore, MET (2 mg/kg) blocked the panicolytic effect produced by PEA, as can be seen by the significant differences in escape 2 and 3 (⁺ p < 0.05) latencies between the MET + PEA and the VEH + PEA groups.

[Fig. 4 B] and [D] shows the results observed in the ETM test for the association (acute, i. p.) of the VEH and SUL (20 mg/kg) in rats chronically treated (i. g.) with the VEH, PAR (3 mg/kg) or PEA (8 mg/kg). For the inhibitory avoidance test ([Fig. 4 B]), the RMANOVA showed a significant main effect on the trials (F_[2.108] = 46.55, p < 0.001), but no significant effect on treatment (F_[5.54] = 1.17, p = 0.33) or on treatment × trial interaction (F_[10.108] = 1.13, p = 0.34). For the escape test ([Fig. 4 D]), the RMANOVA showed a significant main effect on treatment (F_[5.54] = 3.10, p < 0.05), but no significant effect on the trials (F_[2.108] = 2.72, p = 0.07) or on treatment × trial interaction (F_[10.108] = 1.67, p = 0.09). Post-hoc comparisons showed that PAR (3 mg/kg) and PEA (8 mg/kg) significantly increased escape 2 (* p < 0.05) latency compared to the control group, indicating a panicolytic effect. SUL blocked the panicolytic effect of PEA, as can be seen by the significant difference in escape 2 latencies (⁺ p < 0.05) between the SUL + PEA and the VEH + PEA groups, indicating the involvement of dopaminergic neurotransmission in the action mechanism of PEA. A one-way ANOVA did not show significant differences in distance traveled under these different treatments compared to the control group ([Table 3]).

Discussion

This is the first study to evaluate the effects of PEA on rats in the ETM test, an animal model developed to assess defensive behaviors related to specific subtypes of anxiety disorder, generalized anxiety disorder and panic disorder.

The data obtained showed that chronic treatment with PEA (as with PAR) increased escape latency without affecting baseline and inhibitory avoidance latency or locomotion in the circular arena. PEA was therefore found to have a selective panicolytic effect on rats in the ETM test after chronic treatment. The same PEA fraction of guaraná has produced an antidepressant-like effect in the forced swimming test [18].

The main components of the PEA fraction are polyphenols (65 %), consisting of catechin (27 %) and epicatechin (38 %). Catechin and epicatechin are usually present in green teas, red wine, cocoa products and fruits, and can cross the blood-brain barrier after oral administration [22].

Furthermore, polyphenols have antioxidant properties [23], and these active substances may be responsible for the improved cognition produced by Panax ginseng [24] and red ginseng [25].

Antidepressant drugs of different classes, including tricyclics, monoaminoxidase (MAO) inhibitors and SSRI, have been successfully used for the treatment of anxiety disorder subtypes, including generalized anxiety disorder [26], panic disorder [27], obsessive-compulsive disorder [28], social anxiety disorder [29] and post-traumatic stress disorder [30], as well as depressive disorders [31].

No alterations in the growth or body weight of the animals were observed after 24 days of treatment with the PEA fraction. The same PEA fraction of guaraná was evaluated in a toxicological study and showed an LD₅₀ of 1.825 g/kg by oral route in mice and liver toxicity in doses of 150 and 300 mg/kg in rats [32].

The effective doses of PEA (8 mg/kg) and PAR (3 mg/kg) were chosen in order to combine with ineffective doses of MET or SUL, the serotonergic and dopaminergic antagonists, respectively.

MET and SUL both blocked the panicolytic effect produced by PEA in the ETM test. As expected, the panicolytic effect of the SSRI, PAR, was blocked only by MET. These results show that both serotonergic and dopaminergic neurotransmission systems are involved in the panicolytic effect of PEA.

The blockage of the panicolytic effect of PAR by MET but not by SUL is in accordance with expected results for an SSRI, and validates the model. PAR was chosen as positive control in this study because it was the first SSRI approved by the Food and Drug Administration (FDA) for the treatment of panic disorder [27], and other studies have shown its high tolerability and effectiveness for this pathology [33].

Although SSRIs are considered the first-choice treatment for panic disorder, dopamine is also an important neurotransmitter involved in the etiology and treatment of anxiety disorders and depression [34], [35].

In conclusion, the results of the present study demonstrate that PEA is active orally, that it produces a panicolytic effect on rats in the ETM test, and that the serotonergic and dopaminergic neurotransmission systems are involved in this effect. The results suggest that PEA could be a useful drug in the treatment of mood disorders such as panic disorder.

Acknowledgements

The authors would like to thank Capes and FINEP for their financial support of this research, Mr. José Augusto de Souza for collecting and drying the seed samples and Dr. Cássia Mônica Sakuragui for identifying their species.

References

• 1 Kessler R C, Berglund P, Demler O, Jin R, Merikangas K R, Walters E E. Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the national Comorbidity Survey Replication.  Arch Gen Psychiatry. 2005;  62 593-602
  Search in Google Scholar
• 2 DuPont R L, Rice D P, Miller L S, Shiraki S S, Rowland C R, Harwood H J. Economic costs of anxiety disorders.  Anxiety. 1996;  2 167-172
  CrossrefPubMedSearch in Google Scholar
• 3 Henderson M, Glozier N, Elliott K H. Long term sickness absence.  BMJ. 2005;  330 802-803
  CrossrefPubMedSearch in Google Scholar
• 4 Waghorn G, Chant D, White P, Whiteford H. Disability, employment and work performance among persons with ICD-10 anxiety disorders.  Aust N Z J Psychiatry. 2005;  39 55-66
  CrossrefPubMedSearch in Google Scholar
• 5 Mendlowicz M V, Stein M B. Quality of life in individuals with anxiety disorders.  Am J Psychiatry. 2000;  157 669-682
  CrossrefPubMedSearch in Google Scholar
• 6 Blier P, de Montigny C. Serotonin and drug-induced therapeutic responses in major depression, obsessive-compulsive and panic disorders.  Neuropsychopharmacology. 1999;  21 91S-98S
  PubMedSearch in Google Scholar
• 7 Thase M E, Rush A J. Treatment-resistant depression. Bloom FE, Kupfer DJ Psychopharmacology. New York; Raven Press 1995: 1081-1097
  PubMedSearch in Google Scholar
• 8 Domenic A C, Edgar P N. Benzodiazepine treatment of anxiety or insomnia in substance abuse patients.  Am J Addict. 2000;  9 276-284
  CrossrefPubMedSearch in Google Scholar
• 9 Eisenberg D M, Davis R B, Ettner S L, Appel S, Wilkey S, VanRompay M, Kessler R C. Trends in alternative medicine use in the United States 1990 − 1997.  JAMA. 1998;  280 1569-1575
  CrossrefPubMedSearch in Google Scholar
• 10 Astin J A. Why patients use alternative medicine: results of a national study.  JAMA. 1998;  279 1548-1553
  CrossrefPubMedSearch in Google Scholar
• 11 Guerra M P, Nodari R O. Biodiversidade: aspectos biológicos, geográficos, legais e éticos. Simões CMO, Sckenkel EP, Gosman G, Mello JCP, Mentz LA, Petrovick PR Farmacognosia: da planta ao medicamento. Porto Alegre/Florianópolis; UFRGS/UFSC 2001: 13-26
  PubMedSearch in Google Scholar
• 12 Henman A R. Guaraná (Paullinia cupana var. sorbilis): Ecological and social perspectives on an economic plant of the central Amazon basin.  J Ethnopharmacol. 1982;  6 311-338
  CrossrefPubMedSearch in Google Scholar
• 13 Benowitz N L. Clinical pharmacology of caffeine.  Annu Rev Pharmacol. 1990;  41 277-288
  PubMedSearch in Google Scholar
• 14 O'Dea J A. Consumption of nutritional supplements among adolescents: usage and perceived benefits.  Health Educ Res. 2003;  18 98-107
  CrossrefPubMedSearch in Google Scholar
• 15 Mattei R, Dias R F, Espínola E B. Guaraná (Paullinia cupana): toxic behavioral effects in laboratory animals and antioxidant activity in vitro.  J Ethnopharmacol. 1998;  60 111-116
  CrossrefPubMedSearch in Google Scholar
• 16 Kennedy D O, Haskell C F, Wesnes K A, Scholey A B. Improved cognitive performance in human volunteers following administration of guarana (Paullinia cupana) extract: comparison and interaction with Panax ginseng.  Pharmacol Biochem Behav. 2004;  79 401-411
  CrossrefPubMedSearch in Google Scholar
• 17 Otobone F J, Sanches A C, Nagae R, Martins J V C, Obici S, Mello J C P, Audi E A. Effect of crude extract and its semi-purified constituents from guaraná seeds [Paullinia cupana var. sorbilis (Mart.) Lucke] on cognitive performance in Morris water maze in rats.  Braz Arch Biol Technol. 2005;  48 723-728
  PubMedSearch in Google Scholar
• 18 Otobone F J, Sanches A C, Nagae R, Martins J V C, Sela V R, Mello J C P, Audi E A. Effect of lyophilized extracts from guaraná seeds [Paullinia cupana var. sorbilis (Mart.) Ducke] on behavioral profiles in rats.  Phytother Res. 2007;  21 531-535
  CrossrefPubMedSearch in Google Scholar
• 19 Haskell C F, Kennedy D O, Wesnes K A, Milne A L, Scholey A B. A double-blind, placebo-controlled, multi-dose evaluation of the acute behavioural effects of guaraná in humans.  J Psychopharmacol. 2007;  21 65-70
  CrossrefPubMedSearch in Google Scholar
• 20 Pelozo M I G, Cardoso M L C, Mello J C P. Spectrophotometric determination of tannins and caffeine in preparations from Paullinia cupana var. sorbilis.  Braz Arch Biol Technol. 2008;  51 447-451
  CrossrefPubMedSearch in Google Scholar
• 21 Teixeira R C, Zangrossi Jr H, Graeff F G. Behavioral effects of acute and chronic imipramine in the elevated T-maze model of anxiety.  Pharmacol Biochem Behav. 2000;  65 571-576
  CrossrefPubMedSearch in Google Scholar
• 22 El Mohsen M M A, Kuhnle G, Rechner A R, Schroeter H, Rose S, Jenner P, Rice-Evans C A. Uptake and metabolism of epicatechin and its access to the brain after oral ingestion.  Free Radic Biol Med. 2002;  33 1693-1702
  CrossrefPubMedSearch in Google Scholar
• 23 Pietta P G. Flavonoids as antioxidants.  J Nat Prod. 2000;  63 1035-1042
  CrossrefPubMedSearch in Google Scholar
• 24 Ying Y, Zang J T, Shi C Z, Liu Y. Study on the nootropic mechanism of ginsenoside Rb1 and Rb1-influene on mouse brain development.  Acta Pharm Sin. 1994;  29 241-245
  PubMedSearch in Google Scholar
• 25 Lee S C, Moon Y S, You K H. Effect of red ginseng saponins and nootropic drugs on impaired acquisition of ethanol-treated rats in passive avoidance performance.  J Ethnopharmacol. 2000;  69 1-8
  CrossrefPubMedSearch in Google Scholar
• 26 Kim T, Pae C, Yoon S, Bahk W, Jun T, Rhee W, Chae J. Comparison of venlafaxine extended release versus paroxetine for treatment of patients with generalized anxiety disorder.  Psychiatry Clin Neurosci. 2006;  60 347-351
  CrossrefPubMedSearch in Google Scholar
• 27 Pollack M H, Doyle A C. Treatment of panic disorder: Focus on paroxetine.  Psychopharmacol Bull. 2003;  37 53-63
  PubMedSearch in Google Scholar
• 28 Weber M, Talmon S, Schulze I, Boeddinghaus C, Gross G, Schoemaker H, Wicke K M. Running wheel activity is sensitive to acute treatment with selective inhibitors for either serotonin or norepinephrine reuptake.  Psychopharmacology. 2009;  203 753-762
  CrossrefPubMedSearch in Google Scholar
• 29 Lepola U, Bergtholdt B, Lambert J S, Davy K L, Ruggiero L. Controlled-release paroxetine in the treatment of patients with social anxiety disorder.  J Clin Psychiatry. 2004;  65 222-229
  CrossrefPubMedSearch in Google Scholar
• 30 Kim Y, Asukai N, Konishi T, Kato H, Hirotsune H, Maeda M, Inoue H, Narita H, Iwasaki M. Clinical evaluation of paroxetine in post-traumatic stress disorder (PTSD): 52-week, non-comparative open-label study for clinical use experience.  Psychiatry Clin Neurosci. 2008;  62 646-652
  CrossrefPubMedSearch in Google Scholar
• 31 Trivedi M H, Pigott T A, Perera P, Dillingham K E, Carfagno M L, Pitts C D. Effectiveness of low doses of paroxetine controlled release in the treatment of major depressive disorder.  J Clin Psychiatry. 2004;  65 1356-1364
  CrossrefPubMedSearch in Google Scholar
• 32 Antonelli-Ushirobira T M, Kaneshina E N, Gabriel M, Audi E A, Marques L C, Mello J C P. Acute and subchronic toxicological evaluation of the semipurified extract of seeds of guaraná (Paullinia cupana) in rodents.  Food Chem Toxicol. 2010;  48 1817-1820
  PubMedSearch in Google Scholar
• 33 Sheehan D V, Burnhan D B, Iyengar M K, Perera P. Efficacy and tolerability of controlled-release paroxetine in the treatment of panic disorder.  J Clin Psychiatry. 2005;  66 34-40
  CrossrefPubMedSearch in Google Scholar
• 34 Simon N M, Emmanuel N, Ballenger J, Worthington J J, Kinrys G, Korbly N B, Farach F J, Pollack M H. Buproprion sustained release for panic disorder.  Psychopharmacol Bull. 2003;  37 66-72
  PubMedSearch in Google Scholar
• 35 Goodnick P J, Dominguez R A, DeVane C L, Bowden C L. Buproprion slow-release response in depression: diagnosis and biochemistry.  Biol Psychiatry. 1998;  44 629-632
  CrossrefPubMedSearch in Google Scholar

Prof. Dr. Elisabeth Aparecida Audi

Department of Pharmacy and Pharmacology
State University of Maringá

Av. Colombo, 5790

Zona 7, CEP

87020-900 Maringá, PR

Brazil

Phone: + 55 44 30 11 48 44

Fax: + 55 44 32 61 49 99

Email: eaaudi@uem.br

References

• 1 Kessler R C, Berglund P, Demler O, Jin R, Merikangas K R, Walters E E. Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the national Comorbidity Survey Replication.  Arch Gen Psychiatry. 2005;  62 593-602
  Search in Google Scholar
• 2 DuPont R L, Rice D P, Miller L S, Shiraki S S, Rowland C R, Harwood H J. Economic costs of anxiety disorders.  Anxiety. 1996;  2 167-172
  CrossrefPubMedSearch in Google Scholar
• 3 Henderson M, Glozier N, Elliott K H. Long term sickness absence.  BMJ. 2005;  330 802-803
  CrossrefPubMedSearch in Google Scholar
• 4 Waghorn G, Chant D, White P, Whiteford H. Disability, employment and work performance among persons with ICD-10 anxiety disorders.  Aust N Z J Psychiatry. 2005;  39 55-66
  CrossrefPubMedSearch in Google Scholar
• 5 Mendlowicz M V, Stein M B. Quality of life in individuals with anxiety disorders.  Am J Psychiatry. 2000;  157 669-682
  CrossrefPubMedSearch in Google Scholar
• 6 Blier P, de Montigny C. Serotonin and drug-induced therapeutic responses in major depression, obsessive-compulsive and panic disorders.  Neuropsychopharmacology. 1999;  21 91S-98S
  PubMedSearch in Google Scholar
• 7 Thase M E, Rush A J. Treatment-resistant depression. Bloom FE, Kupfer DJ Psychopharmacology. New York; Raven Press 1995: 1081-1097
  PubMedSearch in Google Scholar
• 8 Domenic A C, Edgar P N. Benzodiazepine treatment of anxiety or insomnia in substance abuse patients.  Am J Addict. 2000;  9 276-284
  CrossrefPubMedSearch in Google Scholar
• 9 Eisenberg D M, Davis R B, Ettner S L, Appel S, Wilkey S, VanRompay M, Kessler R C. Trends in alternative medicine use in the United States 1990 − 1997.  JAMA. 1998;  280 1569-1575
  CrossrefPubMedSearch in Google Scholar
• 10 Astin J A. Why patients use alternative medicine: results of a national study.  JAMA. 1998;  279 1548-1553
  CrossrefPubMedSearch in Google Scholar
• 11 Guerra M P, Nodari R O. Biodiversidade: aspectos biológicos, geográficos, legais e éticos. Simões CMO, Sckenkel EP, Gosman G, Mello JCP, Mentz LA, Petrovick PR Farmacognosia: da planta ao medicamento. Porto Alegre/Florianópolis; UFRGS/UFSC 2001: 13-26
  PubMedSearch in Google Scholar
• 12 Henman A R. Guaraná (Paullinia cupana var. sorbilis): Ecological and social perspectives on an economic plant of the central Amazon basin.  J Ethnopharmacol. 1982;  6 311-338
  CrossrefPubMedSearch in Google Scholar
• 13 Benowitz N L. Clinical pharmacology of caffeine.  Annu Rev Pharmacol. 1990;  41 277-288
  PubMedSearch in Google Scholar
• 14 O'Dea J A. Consumption of nutritional supplements among adolescents: usage and perceived benefits.  Health Educ Res. 2003;  18 98-107
  CrossrefPubMedSearch in Google Scholar
• 15 Mattei R, Dias R F, Espínola E B. Guaraná (Paullinia cupana): toxic behavioral effects in laboratory animals and antioxidant activity in vitro.  J Ethnopharmacol. 1998;  60 111-116
  CrossrefPubMedSearch in Google Scholar
• 16 Kennedy D O, Haskell C F, Wesnes K A, Scholey A B. Improved cognitive performance in human volunteers following administration of guarana (Paullinia cupana) extract: comparison and interaction with Panax ginseng.  Pharmacol Biochem Behav. 2004;  79 401-411
  CrossrefPubMedSearch in Google Scholar
• 17 Otobone F J, Sanches A C, Nagae R, Martins J V C, Obici S, Mello J C P, Audi E A. Effect of crude extract and its semi-purified constituents from guaraná seeds [Paullinia cupana var. sorbilis (Mart.) Lucke] on cognitive performance in Morris water maze in rats.  Braz Arch Biol Technol. 2005;  48 723-728
  PubMedSearch in Google Scholar
• 18 Otobone F J, Sanches A C, Nagae R, Martins J V C, Sela V R, Mello J C P, Audi E A. Effect of lyophilized extracts from guaraná seeds [Paullinia cupana var. sorbilis (Mart.) Ducke] on behavioral profiles in rats.  Phytother Res. 2007;  21 531-535
  CrossrefPubMedSearch in Google Scholar
• 19 Haskell C F, Kennedy D O, Wesnes K A, Milne A L, Scholey A B. A double-blind, placebo-controlled, multi-dose evaluation of the acute behavioural effects of guaraná in humans.  J Psychopharmacol. 2007;  21 65-70
  CrossrefPubMedSearch in Google Scholar
• 20 Pelozo M I G, Cardoso M L C, Mello J C P. Spectrophotometric determination of tannins and caffeine in preparations from Paullinia cupana var. sorbilis.  Braz Arch Biol Technol. 2008;  51 447-451
  CrossrefPubMedSearch in Google Scholar
• 21 Teixeira R C, Zangrossi Jr H, Graeff F G. Behavioral effects of acute and chronic imipramine in the elevated T-maze model of anxiety.  Pharmacol Biochem Behav. 2000;  65 571-576
  CrossrefPubMedSearch in Google Scholar
• 22 El Mohsen M M A, Kuhnle G, Rechner A R, Schroeter H, Rose S, Jenner P, Rice-Evans C A. Uptake and metabolism of epicatechin and its access to the brain after oral ingestion.  Free Radic Biol Med. 2002;  33 1693-1702
  CrossrefPubMedSearch in Google Scholar
• 23 Pietta P G. Flavonoids as antioxidants.  J Nat Prod. 2000;  63 1035-1042
  CrossrefPubMedSearch in Google Scholar
• 24 Ying Y, Zang J T, Shi C Z, Liu Y. Study on the nootropic mechanism of ginsenoside Rb1 and Rb1-influene on mouse brain development.  Acta Pharm Sin. 1994;  29 241-245
  PubMedSearch in Google Scholar
• 25 Lee S C, Moon Y S, You K H. Effect of red ginseng saponins and nootropic drugs on impaired acquisition of ethanol-treated rats in passive avoidance performance.  J Ethnopharmacol. 2000;  69 1-8
  CrossrefPubMedSearch in Google Scholar
• 26 Kim T, Pae C, Yoon S, Bahk W, Jun T, Rhee W, Chae J. Comparison of venlafaxine extended release versus paroxetine for treatment of patients with generalized anxiety disorder.  Psychiatry Clin Neurosci. 2006;  60 347-351
  CrossrefPubMedSearch in Google Scholar
• 27 Pollack M H, Doyle A C. Treatment of panic disorder: Focus on paroxetine.  Psychopharmacol Bull. 2003;  37 53-63
  PubMedSearch in Google Scholar
• 28 Weber M, Talmon S, Schulze I, Boeddinghaus C, Gross G, Schoemaker H, Wicke K M. Running wheel activity is sensitive to acute treatment with selective inhibitors for either serotonin or norepinephrine reuptake.  Psychopharmacology. 2009;  203 753-762
  CrossrefPubMedSearch in Google Scholar
• 29 Lepola U, Bergtholdt B, Lambert J S, Davy K L, Ruggiero L. Controlled-release paroxetine in the treatment of patients with social anxiety disorder.  J Clin Psychiatry. 2004;  65 222-229
  CrossrefPubMedSearch in Google Scholar
• 30 Kim Y, Asukai N, Konishi T, Kato H, Hirotsune H, Maeda M, Inoue H, Narita H, Iwasaki M. Clinical evaluation of paroxetine in post-traumatic stress disorder (PTSD): 52-week, non-comparative open-label study for clinical use experience.  Psychiatry Clin Neurosci. 2008;  62 646-652
  CrossrefPubMedSearch in Google Scholar
• 31 Trivedi M H, Pigott T A, Perera P, Dillingham K E, Carfagno M L, Pitts C D. Effectiveness of low doses of paroxetine controlled release in the treatment of major depressive disorder.  J Clin Psychiatry. 2004;  65 1356-1364
  CrossrefPubMedSearch in Google Scholar
• 32 Antonelli-Ushirobira T M, Kaneshina E N, Gabriel M, Audi E A, Marques L C, Mello J C P. Acute and subchronic toxicological evaluation of the semipurified extract of seeds of guaraná (Paullinia cupana) in rodents.  Food Chem Toxicol. 2010;  48 1817-1820
  PubMedSearch in Google Scholar
• 33 Sheehan D V, Burnhan D B, Iyengar M K, Perera P. Efficacy and tolerability of controlled-release paroxetine in the treatment of panic disorder.  J Clin Psychiatry. 2005;  66 34-40
  CrossrefPubMedSearch in Google Scholar
• 34 Simon N M, Emmanuel N, Ballenger J, Worthington J J, Kinrys G, Korbly N B, Farach F J, Pollack M H. Buproprion sustained release for panic disorder.  Psychopharmacol Bull. 2003;  37 66-72
  PubMedSearch in Google Scholar
• 35 Goodnick P J, Dominguez R A, DeVane C L, Bowden C L. Buproprion slow-release response in depression: diagnosis and biochemistry.  Biol Psychiatry. 1998;  44 629-632
  CrossrefPubMedSearch in Google Scholar

Prof. Dr. Elisabeth Aparecida Audi

Department of Pharmacy and Pharmacology
State University of Maringá

Av. Colombo, 5790

Zona 7, CEP

87020-900 Maringá, PR

Brazil

Phone: + 55 44 30 11 48 44

Fax: + 55 44 32 61 49 99

Email: eaaudi@uem.br