Passiflora incarnata L. (Passionflower) extracts elicit GABA currents in hippocampal neurons in vitro, and show anxiogenic and anticonvulsant effects in vivo, varying with extraction method

Common herbs for stress: The science and strategy of a botanical medicine approach to self-care

Frontline healthcare workers have reported elevated levels of stress and increase prevalence of burnout symptoms since the onset of the COVID-19 pandemic. With these heightened levels of stress and burnout comes a need for more evidence-based interventions to address these symptoms earlier, in both a safe and effective way. Some common botanical medicines have a measurable effect on perceived stress, neurotransmitter levels, and circulating cortisol levels indicating their ability to modify the stress response. Botanical medicines are often relatively low cost, increasingly available in retail stores and online marketplaces, and show relatively low reports of adverse effects, making these medicinal herbs an important option for addressing work-related stress for healthcare workers.

Therapeutic Potential of Quercetin and its Derivatives in Epilepsy: Evidence from Preclinical Studies

Quercetin is a polyphenolic bioactive compound highly enriched in dietary fruits, vegetables, nuts, and berries. Quercetin and its derivatives like rutin and hyperoside are known for their beneficial effects in various neurological conditions including epilepsy. The clinical studies of quercetin and its derivatives in relation to epilepsy are limited. This review provides the evidence of most recent knowledge of anticonvulsant properties of quercetin and its derivatives on preclinical studies. Additionally, the studies demonstrating antiseizure potential of various plants extracts enriched with quercetin and its derivatives has been included in this review. Herein, we have also discussed neuroprotective effect of these bioactive compound and presented underlying mechanisms responsible for anticonvulsant properties in brief. Finally, limitations of quercetin and its derivatives as antiseizure compounds as well as possible strategies to enhance efficacy have also been discussed.

Flavonoid-rich fraction from Croton blanchetianus (Euphorbiaceae) leaves exerts peripheral and central analgesic effects by acting via the opioid and cholinergic systems

The ethanolic extract from Croton blanchetianus leaves has been shown to have antinociceptive activity in mice. Here, we investigated the antinociceptive activity of an ethyl acetate fraction (EAF) from this extract in mice and the possible pathways involved in the analgesic effect. Adverse effects on behavior and motor coordination were also evaluated. The EAF was characterized by liquid chromatography coupled with mass spectrometry and evaluated (12.5, 25, and 50 mg/kg per os) in the acetic acid-induced abdominal writhing, formalin, hot plate, and tail immersion assays. Naloxone, atropine, glibenclamide, prazosin, or yohimbine was pre-administered to mice to investigate the involved pathways in the formalin test. The open-field, rotarod, and elevated plus-maze tests were used to assess behavior and locomotion. The main components of the EAF were quercetin-3-O-(2-rhamnosyl) rutinoside, hyperoside, quercetin rutinoside pentoside, and quercetin hexoside deoxyhexoside. EAF showed antinociceptive effects in all models and was effective against both neurogenic and inflammatory pain. The reversion of the effects in the formalin test by naloxone and atropine revealed that the EAF acted via the opioid and cholinergic systems. In the open-field test, the behavior of the animals treated with the EAF was like that of control, except at the highest dose, when hypnosis, eyelid ptosis, decreased walking, hygiene, and rearing behaviors were observed. No muscle relaxant effect was observed, but an anxiogenic effect was observed at all doses. This study provides new scientific evidence on the pharmacological properties of C. blanchetianus leaves and their potential for the development of phytomedicines with analgesic properties.

Dietary Euterpe oleracea Mart. attenuates seizures and damage to lipids in the brain of Colossoma macropomum

The Amazonian açai fruit (Euterpe oleracea) has shown promising anticonvulsant properties, comparable to those of diazepam (BDZ) in in vivo models submitted to pentylenetetrazole (PTZ). PTZ is a classic convulsant agent used in studies for the purpose of screening anticonvulsants and investigating the mechanisms of epilepsy. Herein, we aimed to determine, for the first time, the effect of dietary administration of lyophilized E. oleracea (LEO) on PTZ-induced seizures, using juvenile Colossoma macropomum fish (9.1 ± 1.5 g) as a model. A control diet (0.00% LEO) and two levels of LEO inclusion were established: 5.00% and 10.0% LEO (w/w). Fish were divided into five groups (n = 5): control (0.9% physiological solution; i.p.), PTZ (PTZ 150 mg kg^-1; i.p.), PTZ LEO 5.00%, PTZ LEO 10.0%, and BDZ-PTZ (BDZ: diazepam 10 mg kg^-1; i.p.). In addition to the electroencephalography (EEG), the lipid peroxidation (TBARS) was quantified in the brain, along with the characterization of behavioral responses. Fish receiving PTZ showed intense action potential bursts (APB), which overlapped with a hyperactive behavior. In PTZ LEO 5.00% and 10.0% groups, convulsive behavior was significantly reduced compared to the PTZ group. Fish fed 5.00% or 10.0% LEO and exposed to PTZ showed less excitability and lower mean amplitude in tracings. The inclusion of 10.0% LEO in the diet prevented the increase in mean amplitude of the EEG waves by 80%, without significant differences to the quantified mean amplitude of the BDZ-PTZ group. TBARS concentration was reduced by 60% in the brain of fish fed 10.0% LEO-enriched diets relative to the PTZ-administered group. The results of this study demonstrated the anticonvulsant and protective roles of LEO to the brain, and the dietary inclusion of LEO seems to be promising for the formulation of functional diets. Results of this study may boost the interest on the anti-seizurogenic properties of Euterpe oleracea, including the development of new approaches for the prevention of seizures in humans and animals with low epileptic threshold.

A Pharmacological Perspective on Plant-derived Bioactive Molecules for Epilepsy

Epilepsy is a related chronic neurological condition of a predisposition for recurrent epileptic seizures, with various manifestations and causes. Although there are antiepileptic drugs, complementary natural therapies are widely used. The purpose of this systematic review was to analyze the antiepileptic/anticonvulsant pharmacological properties of plant-food derived bioactive molecules. In this regard, a systematic review of the PubMed database was made based on the inclusion criteria. Natural compounds/herbs with scientifically proven antiepileptic properties were selected. Experimental pharmacological studies in vitro and in vivo have shown that flavonoids, alkaloids and terpenoids may have anticonvulsant mechanisms similar to the new generation antiepileptic drugs. The relationships of structure-anticonvulsant effect, pharmacological models, seizure-inducing factors and response, effective dose were also analyzed and discussed. The results of in vitro and in vivo pharmacological studies analyzed in this systematic review support the clinical importance of plant-food-derived bioactive molecules for the complementary treatment of epilepsy. Thus, are opened new perspectives to develop new natural anticonvulsant drugs.

Herbal Remedies and Their Possible Effect on the GABAergic System and Sleep

Sleep is an essential component of physical and emotional well-being, and lack, or disruption, of sleep due to insomnia is a highly prevalent problem. The interest in complementary and alternative medicines for treating or preventing insomnia has increased recently. Centuries-old herbal treatments, popular for their safety and effectiveness, include valerian, passionflower, lemon balm, lavender, and Californian poppy. These herbal medicines have been shown to reduce sleep latency and increase subjective and objective measures of sleep quality. Research into their molecular components revealed that their sedative and sleep-promoting properties rely on interactions with various neurotransmitter systems in the brain. Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter that plays a major role in controlling different vigilance states. GABA receptors are the targets of many pharmacological treatments for insomnia, such as benzodiazepines. Here, we perform a systematic analysis of studies assessing the mechanisms of action of various herbal medicines on different subtypes of GABA receptors in the context of sleep control. Currently available evidence suggests that herbal extracts may exert some of their hypnotic and anxiolytic activity through interacting with GABA receptors and modulating GABAergic signaling in the brain, but their mechanism of action in the treatment of insomnia is not completely understood.

Sintocalmy, a Passiflora incarnata Based Herbal, Attenuates Morphine Withdrawal in Mice

Chronic opioid use changes brain chemistry in areas related to reward processes, memory, decision-making, and addiction. Both neurons and astrocytes are affected, ultimately leading to dependence. Passiflora incarnata L. (Passifloraceae) is the basis of frequently used herbals to manage anxiety and insomnia, with proven central nervous system depressant effects. Anti-addiction properties of P. incarnata have been reported. The aim of this study was to investigate the effect of a commercial extract of Passiflora incarnata (Sintocalmy®, Aché Laboratory) in the naloxone-induced jumping mice model of morphine withdrawal. In addition, glial fibrillary acidic protein (GFAP) and S100 calcium-binding protein B (S100B) levels were assessed in the frontal cortex and hippocampus, and DNA damage was verified on blood cells. In order to improve solubilization a Sintocalmy methanol extract (SME) was used. SME is mainly composed by flavonoids isovitexin and vitexin. The effects of SME 50, 100 and 200 mg/kg (i.p.) were evaluated in the naloxone-induced withdrawal syndrome in mice. SME 50 and SME 100 mg/kg decreased naloxone-induced jumping in morphine-dependent mice without reducing locomotor activity. No alterations were found in GFAP levels, however SME 50 mg/kg prevented the S100B increase in the frontal cortex and DNA damage. This study shows anti-addiction effects for a commercial standardized extract of P. incarnata and suggests the relevance of proper clinical assessment.

Passiflora incarnata in Neuropsychiatric Disorders-A Systematic Review

Background: Stress is a natural response of the body, induced by factors of a physical (hunger, thirst, and infection) and/or psychological (perceived threat, anxiety, or concern) nature. Chronic, long-term stress may cause problems with sleep, concentration, and memory, as well as affective disorders. The passionflower (Passiflora incarnata) is a perennial plant with documented therapeutic properties. The literature data suggest that the passionflower itself, as well as its preparations, helps reduce stress and can therefore be helpful in the treatment of insomnia, anxiety, and depression. The objective of this systematic review was to evaluate Passiflora incarnata in terms of its neuropsychiatric effects. Methods: The scientific databases PubMed, ClinTrials.gov, and Embase were searched up to 22 October 2019. The search identified randomized clinical trials describing the effects of Passiflora incarnata in neuropsychiatric disorders. Results: The systematic review included nine clinical trials. The duration of the studies included in the analysis varied widely, from one day up to 30 days. Study participants were no less than 18 years old. In each of the papers, the effects of passionflower were measured by using a number of different tests and scales. The majority of studies reported reduced anxiety levels following the administration of Passiflora incarnata preparations, with the effect less evident in people with mild anxiety symptoms. No adverse effects, including memory loss or collapse of psychometric functions, were observed. Conclusion: Passiflora incarnata may be helpful in treating some symptoms in neuropsychiatric patients.

Brain foods - the role of diet in brain performance and health

The performance of the human brain is based on an interplay between the inherited genotype and external environmental factors, including diet. Food and nutrition, essential in maintenance of brain performance, also aid in prevention and treatment of mental disorders. Both the overall composition of the human diet and specific dietary components have been shown to have an impact on brain function in various experimental models and epidemiological studies. This narrative review provides an overview of the role of diet in 5 key areas of brain function related to mental health and performance, including: (1) brain development, (2) signaling networks and neurotransmitters in the brain, (3) cognition and memory, (4) the balance between protein formation and degradation, and (5) deteriorative effects due to chronic inflammatory processes. Finally, the role of diet in epigenetic regulation of brain physiology is discussed.

Profiling of the known-unknown Passiflora variant complement by liquid chromatography - Ion mobility - Mass spectrometry

Liquid Chromatography - Ion Mobility - Mass Spectrometry (LC-IM-MS) was utilized for non-targeted screening analysis to understand the variance in the composition of Passiflora species. Multivariate analysis was employed to explore a chemometric processing strategy for IM based Passiflora variant differentation. This approach was applied to the comparative analyses of extracts of the medicinal plants Passiflora alata, Passiflora edulis, Passiflora incarnata and Passiflora caerulea. In total, 255 occurrences of IM-MS resolved coeluting marker isomers and isobaric species were detected, providing increased coverage and specificity of species component markers compared to conventional LC-MS. A large proportion of medical plant phytochemical analysis information often remains redundant in that it is not phenotypic specific. Here, generation of Passiflora variant 'known-unknown' libraries has been used to compare Passiflora species to investigate unique variant features. Investigations of predicted collision cross section have enabled comparison of an element of the 'known-unknown' IM isomeric complement to be performed, facilitating a reduction in the number of possible variant unique isomeric identifications. In combination with spectral interpretation, it has been possible to resassign isomeric 'known-unknowns' as 'knowns'. The strategies employed illustrates the potential to facilitate identification of medicinal plant phytochemical components.

Cardiac protection of germinated brown rice extract in rabbit model of chronic myocardial infarction

Ischemic heart disease is a leading cause of mortality in the world. This study aimed to investigate the cardioprotective effects of germinated brown rice (GBR) on a rabbit model of chronic myocardial infarction. Eighteen New Zealand white rabbits were randomly divided into three groups receiving: 1) regular rabbit food; 2) regular rabbit food plus vehicle; and 3) regular rabbit food plus GBR for 120 d. The left circumflex coronary artery was ligated to induce myocardial ischemia 60 d after starting the experiment (baseline). Heart functions were monitored by electrocardiography and echocardiography at 0, 30, and 60 d after coronary artery ligation. The incidences of heart rate (HR) and ventricular arrhythmias have been compared between groups. GBR showed the effects to prevent life-threatening ventricular tachycardia and electrocardiographic signs of myocardial ischemia in a model of arrhythmias. GBR consumption group exhibited significantly improved cardiac function and reduced the HR, along with reduced mean arterial pressure and plasma glucose level. The results demonstrated that GBR exerts cardioprotective effects against chronic myocardial injury in rabbits. These biological actions of GBR may explain the benefits gained from the use of GBR products as a possible prophylactic lifestyle intervention.

Metabolic fingerprinting of banana passion fruits and its correlation with quorum quenching activity

Banana passion fruit of the Passiflora genus, are commercially cultivated on a small to medium scale, mainly as edible fruits or as components of traditional herbal medicines. This subgenus comprises several species and hybrid specimens that grow readily in the wild. Due to their taxonomical complexity, many of these species have recently been reclassified (Ocampo Pérez and Coppens d'Eeckenbrugge, 2017), and their chemical profile has still to be determined. In this study, an ¹H NMR-based platform was applied to the chemical profiling of seven wild species of the Passiflora subgenus, and UHPLC-DAD-MS was additionally used for the identification of phenolic compounds. A total of 59 compounds were detected including 26 O- and C-glycosidated flavonoids and polyphenols, nine organic acids, seven amino acids, GABA, sucrose, glucose, myo-inositol, and five other non-identified compounds. Two of the identified compounds are the previously undescribed C-glycosyl flavonoids, apigenin-4'-O-β-glucopyranosyl, 8-C-β-(6″acetyl)-glucopyranoside and apigenin-4-O-β-glucopyranosyl-8-C-β-neohesperidoside. These C-glycosyl flavonoids were isolated to confirm their proposed structures by NMR and LCMS analysis. The PCA score plots obtained from the ¹H NMR data of the studied Passiflora samples showed P. cumbalensis and P. uribei as the species with the most distinguishable chemical profile. In addition, a correlation analysis using OPLS-DA was conducted between ¹H-NMR data and the quorum quenching activity (QQ) of Chromobacterium violaceum ATCC 31532. This analysis revealed P. lehmannii, and P. uribei extracts to be the most active, and apigenin-4'-O-β-glucopyranosyl, 8-C-β-(6″acetyl)-glucopyranoside and apigenin-4-O-β-glucopyranosyl-8-C-β-neohesperidoside were identified as possibly responsible for the QQ activity. To confirm this, QQ activity of both compounds was tested against C. violaceum ATCC 3153. An inhibition of violacein production of 0.135 mM (100 μg/mL) and 0.472 mM (300 μg/mL) was observed for apigenin-4'-O-β-glucopyranosyl,8-C-β-(6″acetyl)-glucopyranoside and apigenin-4-O-β-glucopyranosyl-8-C-β-neohesperidoside respectively, while bacterial growth was unaffected in both cases. Furthermore, both compounds showed the ability to inhibit the production of the toxoflavin of the phytopathogen Burkholderia glumae ATCC 33617.

Garlic passion fruit (Passiflora tenuifila Killip): Assessment of eventual acute toxicity, anxiolytic, sedative, and anticonvulsant effects using in vivo assays

Several Passiflora species are known for their sedative and anxiolytic properties. However, the functional properties of Passiflora tenuifila Killip are still unexplored. The objective of this work was to evaluate the phenolic composition and acute toxicity, anxiolytic, sedative, and anticonvulsant effects using in vivo assays. The whole fruit (peel, pulp, and seed) was lyophilized and used for all assays. LC-MS showed 19 phenolic compounds, tentatively identified as flavonoids and phenolic acids. Acute treatment with single doses of up to 2000 mg kg^-1 in Wistar rats showed no signs of mortality or toxicity over 14 days. The assay of functional effects was performed with Swiss mice, four groups, received by gavage, doses of P. tenuifila (200 or 400 mg kg^-1 body weight), water, and diazepam (as negative and positive control), and behavior tests were performed after 60 min of the treatments. The animals treated with P. tenuifila fruit showed a significant decrease in locomotor activity, indicating a sedative and anxiolytic activity. No significant changes were observed in the rotarod apparatus, suggesting that the P. tenuifila fruit did not cause muscle relaxation. The 400 mg kg^-1 dose of P. tenuifila exerted a protective effect against pentylenetetrazole-induced seizures, decreasing the severity and not causing the death of the animals. In conclusion, P. tenuifila showed no acute toxicity and had a promising effect as an anxiolytic agent, hypnotic-sedative and anticonvulsant, which could be related to its composition of flavonoids and phenolic acids.

Passiflora caerulea L. fruit extract and its metabolites ameliorate epileptic seizure, cognitive deficit and oxidative stress in pilocarpine-induced epileptic mice

The anticonvulsant potential of aqueous fruit extract of Passiflora caerulea (PCAE) was evaluated in swiss albino mice induced by pilocarpine. The antioxidant activities of PCAE were determined which showed strong antioxidant activity and the polyphenol compounds such as ginsenoside, naringenin, chrysoeriol 8-c-glucoside, luteolin-6-C-glucoside, apigenin-6,8-di-C-β-D-glucopyranoside were profiled through RP-HPLC and UPLC-ESI-MS/MS. Chronic effects of PCAE on pilocarpine (85 mg/kg; i.p)-induced convulsions were evaluated in Swiss adult male albino mice. PCAE at 100 and 200 mg/kg, (p.o.) and diazepam (5 mg/kg, i.p) were administered once daily for 15 days. In Y-maze test, percentage of correct entry by pilocarpine administered animals were significantly lower when compared to control, whereas PCAE at both doses improved the alteration score significantly. Administration of higher dose (200 mg/kg) of PCAE significantly delayed onset of convulsions and decreased duration of clonic convulsions. Association of ROS production during seizure period was further confirmed by histopathological studies revealing loss of normal neuronal cells in hippocampus region. The data obtained showed anticonvulsant activity and improved cognitive function; reduced the oxidative damage and significantly activated the cholinergic neurotransmission in a dose dependent manner similar to diazepam which is evident in the biochemical parameters and histopathological study, suggesting therapeutic potential for epilepsy and neurodegeneration.

Development and validation of a high-performance thin-layer chromatographic method for the quantitative analysis of vitexin in Passiflora foetida herbal formulations

The aim of this study is the development of validated HPTLC method for the quantification of vitexin from Passiflora foetida commercial herbal formulations. The developed method was validated, in accordance with ICH guidelines for precision, accuracy, specificity and robustness. The plate was developed using ethyl acetate:methanol:water:formic acid 30:4:2:1(%, v/v/v/v) on 20 × 10 cm glass coated silica gel 60 F₂₅₄ plates and the developed plate was scanned and quantified densitometrically at λ = 340 nm. Linear regression analysis revealed a good linear relationship between peak area and amount of vitexin in the range of 100-700 ng/spot. The amount of vitexin in nine commercial herbal formulations was successfully quantified by the developed HPTLC method. The developed and validated high performance thin layer chromatographic method offers a new sensitive and reliable tool for quantification of vitexinin in various herbal formulations containing Passiflora foetida.

Insights about multi-targeting and synergistic neuromodulators in Ayurvedic herbs against epilepsy: integrated computational studies on drug-target and protein-protein interaction networks

Epilepsy, that comprises a wide spectrum of neuronal disorders and accounts for about one percent of global disease burden affecting people of all age groups, is recognised as apasmara in the traditional medicinal system of Indian antiquity commonly known as Ayurveda. Towards exploring the molecular level complex regulatory mechanisms of 63 anti-epileptic Ayurvedic herbs and thoroughly examining the multi-targeting and synergistic potential of 349 drug-like phytochemicals (DPCs) found therein, in this study, we develop an integrated computational framework comprising of network pharmacology and molecular docking studies. Neuromodulatory prospects of anti-epileptic herbs are probed and, as a special case study, DPCs that can regulate metabotropic glutamate receptors (mGluRs) are inspected. A novel methodology to screen and systematically analyse the DPCs having similar neuromodulatory potential vis-à-vis DrugBank compounds (NeuMoDs) is developed and 11 NeuMoDs are reported. A repertoire of 74 DPCs having poly-pharmacological similarity with anti-epileptic DrugBank compounds and those under clinical trials is also reported. Further, high-confidence PPI-network specific to epileptic protein-targets is developed and the potential of DPCs to regulate its functional modules is investigated. We believe that the presented schema can open-up exhaustive explorations of indigenous herbs towards meticulous identification of clinically relevant DPCs against various diseases and disorders.

Complementary Medicine Therapies That May Assist With Weight Loss: A Narrative Review

Objective

The purpose of this study was to review the potential effects of traditional Chinese medicine-which includes acupuncture; electroacupuncture; plum blossom needle hammer; auricular acupuncture; herbs that balance hormones, regulate neurotransmitters, induce sedative effects, and increase thermogenesis; and functional foods that can suppress the appetite-as an adjunct therapy for weight loss.

Methods

A narrative review of the current literature was performed using searches of MEDLINE and 4 scholarly texts. The inclusion criteria for the review consisted of studies that were performed from 2005 to 2016.

Results

In general, some traditional Chinese medicine modalities claim to promote weight loss. Acupuncture, electroacupuncture, and herbs aim to reduce stress-related food cravings. These therapeutic approaches aim to downregulate dopamine and leptin levels, suppressing the appetite. Other attributes of these therapies are increasing uncoupling protein-1 activity promoting thermogenesis, which contributes to weight loss. In addition, acupuncture, electroacupuncture, and Cimicifuga racemosa may regulate estrogen, which could attenuate the appetite, assisting in weight-loss programs.

Conclusion

The literature reviewed includes information that describes how traditional Chinese medicine, herbal medicine, or functional foods as adjunct therapies may be beneficial for weight-loss programs.

Improvement in neurogenesis and memory function by administration of Passiflora incarnata L. extract applied to sleep disorder in rodent models

Recently, there have been reports that chronic insomnia acts as an insult in the brain, causing memory loss through the production of ROS, inflammation, and, Alzheimer's disease if persistent. Insomnia remains the leading cause of sleep disturbance and as such has serious implications for public health. Patients with Alzheimer's disease are also known to suffer from severe sleep disturbance. Meanwhile, vitexin is a key ingredient in Passiflora incarnata L (passion flower, PF) extract, which is known to help with sleep. This medicinal plant has been used as a folk remedy for sedation, anxiety and sleep since centuries ago, but the standardization work has not been done and the extent of the effect has not been clearly demonstrated. For this reason, we tried to test the possibility that repeated administration of PF could improve the memory by promoting hippocampal neurogenesis at the DBA/2 mice known have inherited sleep disorders, as well as preventive effects of Alzheimer's disease. Here, we found that vitexin, which is the main bioactive component of ethanol extracts from leaves and fruits (ratio; 8:2) of PF, confirmed the improvement of neurogenesis (DCX) of DBA/2 mice repeated PF oral administration by immunohistochemistry (IHC) and western blot analysis. PF-treated group showed increased the neurotrophic factor (BDNF) in the hippocampus compared with that of vehicle-treated group, but the inflammation markers Iba-1 (microglial marker) and COX-2 were inconsistent between the groups. However, we found COX-2 signal is essential for hippocampal neurogenesis according to the additional IHC experiments using COX-2 inhibitor and pIkappaB have shown. In addition, although prescription sleeping pills have been reported to show significant changes in appetite and metabolic rate from time to time, no changes in the feeding behavior, body weight, metabolic rate and body composition of the animals were observed by administration of PF. Interestingly, we found that short-term oral administration of PF displayed improved memory according to the water maze test. Quantitative analysis of Tau protein, which is a marker of Alzheimer's disease, was performed in the SD rats and DBA/2 mice by repeated PF oral administration and pTau/Tau values were significantly decreased in PF-treated group than vehicle-treated group. In conclusion, our results suggest that PF lead high hippocampal neurogenesis in the animals even in inherited sleep-disturbed animals. The increased hippocampal neurogenesis functionally enhanced memory and learning functions by repeated PF oral administration. These results identify PF as a potential therapy for enhancing memory functions and prevention of Alzheimer's disease through actions on the hippocampus.

The effects of herbal medicine on epilepsy

Traditional herbal medicine plays a significant role in the treatment of epilepsy. Though herbal medicine is widely used in antiepileptic treatment, there is a lack of robust evidence for efficacy and toxicity of most herbs. Besides, the herbal medicine should be subject to evidence-based scrutiny. In this context, we present a review to introduce the effects of herbal medicine on epilepsy. However, hundreds of herbal medicines have been investigated in the available studies. Some commonly used herbal medicines for epilepsy have been listed in our study. The overwhelming majority of these data are based on animal experiments. The lack of clinical data places constraints on the clinical recommendation of herbal medicine. Our study may conduct further studies and provide some insight on the development of anti-epileptic drugs.

The sedative activity of flavonoids from Passiflora quadrangularis is mediated through the GABAergic pathway

The aim of this study was to investigate the sedative activity of the aqueous leaf extract of Passiflora quadrangularis, a species that is widely cultivated and consumed in South America, and to identify its main constituents and elucidate the involvement of the GABAergic pathway in its mechanism of action. The bioguided fractionation of the crude extract showed a positive relationship between the sedative activity of the extract and its flavonoids. The methods employed to identify and isolate its main flavonoids resulted in the identification of vitexin-2''-O-xyloside, vitexin-2''-O-glucoside, orientin-2''-O-xyloside and orientin-2''-O-glucoside. Vitexin-2"-O-xyloside, the major flavonoid of the extract, showed sedative activity after oral administration in mice.

Lumbee traditional medicine: Neuroprotective activities of medicinal plants used to treat Parkinson's disease-related symptoms

ETHNOPHARMACOLOGICAL RELEVANCE

Parkinson's disease (PD) is a neurodegenerative disorder characterized by a loss of dopaminergic neurons in the substantia nigra pars compacta and the presence in surviving neurons of Lewy body inclusions enriched with aggregated forms of the presynaptic protein α-synuclein (aSyn). Although current therapies provide temporary symptomatic relief, they do not slow the underlying neurodegeneration in the midbrain. In this study, we analyzed contemporary herbal medicinal practices used by members of the Lumbee tribe to treat PD-related symptoms, in an effort to identify safe and effective herbal medicines to treat PD.

AIM OF THE STUDY

The aims of this study were to (i) document medicinal plants used by Lumbee Indians to treat PD and PD-related symptoms, and (ii) characterize a subset of plant candidates in terms of their ability to alleviate neurotoxicity elicited by PD-related insults and their potential mechanisms of neuroprotection.

MATERIALS AND METHODS

Interviews of Lumbee healers and local people were carried out in Pembroke, North Carolina, and in surrounding towns. Plant samples were collected and prepared as water extracts for subsequent analysis. Extracts were characterized in terms of their ability to induce activation of the nuclear factor E2-related factor 2 (Nrf2) antioxidant response in cortical astrocytes. An extract prepared from Sambucus caerulea flowers (elderflower extract) was further examined for the ability to induce Nrf2-mediated transcription in induced pluripotent stem cell (iPSC)-derived astrocytes and primary midbrain cultures, to ameliorate mitochondrial dysfunction, and to alleviate rotenone- or aSyn-mediated neurotoxicity.

RESULTS

The ethnopharmacological interviews resulted in the documentation of 32 medicinal plants used to treat PD-related symptoms and 40 plants used to treat other disorders. A polyphenol-rich extract prepared from elderflower activated the Nrf2-mediated antioxidant response in cortical astrocytes, iPSC-derived astrocytes, and primary midbrain cultures, apparently via the inhibition of Nrf2 degradation mediated by the ubiquitin proteasome system. Furthermore, the elderflower extract rescued mitochondrial functional deficits in a neuronal cell line and alleviated neurotoxicity elicited by rotenone and aSyn in primary midbrain cultures.

CONCLUSIONS

These results highlight potential therapeutic benefits of botanical extracts used in traditional Lumbee medicine, and they provide insight into mechanisms by which an elderflower extract could suppress neurotoxicity elicited by environmental and genetic PD-related insults.

Standardized Passiflora incarnata L. Extract Reverts the Analgesia Induced by Alcohol Withdrawal in Rats

Passiflora incarnata L. (Passifloraceae) has been traditionally used for treatment of anxiety, insomnia, drug addiction, mild infections, and pain. The aim of this study was to investigate the effect of a commercial extract of P. incarnata in the analgesia induced by alcohol withdrawal syndrome in rats. In addition, brain-derived neurotrophic factor and interleukin-10 levels were evaluated in prefrontal cortex, brainstem, and hippocampus. Male adult rats received by oral gavage: (1: water group) water for 19 days, 1 day interval and water (8 days); (2: P. incarnata group) water for 19 days, 1 day interval and P. incarnata 200 mg/kg (8 days); (3: alcohol withdrawal group) alcohol for 19 days, 1 day interval and water (8 days); and (4: P. incarnata in alcohol withdrawal) alcohol for 19 days, 1 day interval and P. incarnata 200 mg/kg (8 days). The tail-flick and hot plate tests were used as nociceptive response measures. Confirming previous study of our group, it was showed that alcohol-treated groups presented an increase in the nociceptive thresholds after alcohol withdrawal, which was reverted by P. incarnata, measured by the hot plate test. Besides, alcohol treatment increased brain-derived neurotrophic factor and interleukin-10 levels in prefrontal cortex, which was not reverted by P. incarnata. Considering these results, the P. incarnata treatment might be a potential therapy in the alcohol withdrawal syndrome. Copyright © 2017 John Wiley & Sons, Ltd.

Passionflower Extract Induces High-amplitude Rhythms without Phase Shifts in the Expression of Several Circadian Clock Genes in Vitro and in Vivo

Circadian rhythms play key roles in the regulation of physiological and behavioral systems including wake-sleep cycles. We evaluated the effects of passionflower (aerial parts of Passiflora incarnata Linnaeus) extract (PFE) on circadian rhythms using NIH3T3 cells and mice. PFE (100 μg/mL) induced high-amplitude rhythms in the expression of period circadian protein (Per) 2, cryptochrome (Cry) 1, superoxide dismutase (SOD) 1, and glutathione peroxidase (GPx) in vitro from 12 h after a treatment with serum-rich medium. Isovitexin 2"-O-glucoside, isoschaftoside, and homoorientin, which were purified from PFE, also significantly enhanced Per2 mRNA expression at 20 h. An oral treatment with PFE (100 mg/kg/day) at zeitgeber time (ZT) 0 h for 15 days improved sleep latencies and sleeping times in the pentobarbital-induced sleep test in mice, similar to muscimol (0.2 mg/kg, i.p.). PFE induced high-amplitude rhythms without obvious phase shifts in serum corticosterone levels and the expression of Per1, Per2, and Cry1 in the liver as well as NIH3T3 cells. However, in the cerebrum, PFE enhanced the circadian expression of brain-muscle ARNT-like protein (Bmal) 1, circadian locomotor output cycles kaput (Clock), and Per1. Regarding this difference, we suggest the involvement of several neurotransmitters that influence the circadian rhythm. Indeed, PFE significantly increased dopamine levels at ZT 18 h, and then affected the mRNA expression of the synthetic and metabolic enzymes such as monoamine oxidase (MAO), catechol-O-methyltransferase (COMT), and glutamic acid decarboxylase (GAD). The results obtained show that PFE positively modulates circadian rhythms by inducing high-amplitude rhythms in the expression of several circadian clock genes.

Ethnopharmacological approaches in mood and anxiety disorders. The relevance of the oxidative stress status

Neurodegenerative diseases and psychiatric disorders are one of the most important pathologies that lead to increased morbidity in populations. Both mood and anxiety disorders include mental disorders not caused by detectable organic abnormalities of the brain. At the molecular level, affective spectrum symptomatology is due to neurotransmitter dysregulation including receptor or transporter impairments and also due to faulty intracellular signaling that generally leads to impaired neurotransmission. Also, recent studies have shown the relationship between oxidative stress and the development of affective disorders. Since classical medication can cause major side effects and alternative approaches tend to be more and more trusted, it seems that plant extracts-based complementary therapies may offer superior yielding and safety compared to traditional medication.

Passiflora incarnata attenuation of neuropathic allodynia and vulvodynia apropos GABA-ergic and opioidergic antinociceptive and behavioural mechanisms

Background

Passiflora incarnata is widely used as an anxiolytic and sedative due to its putative GABAergic properties. Passiflora incarnata L. methanolic extract (PI-ME) was evaluated in an animal model of streptozotocin-induced diabetic neuropathic allodynia and vulvodynia in rats along with antinociceptive, anxiolytic and sedative activities in mice in order to examine possible underlying mechanisms.

Methods

PI-ME was tested preliminary for qualitative phytochemical analysis and then quantitatively by proximate and GC-MS analysis. The antinociceptive property was evaluated using the abdominal constriction assay and hot plate test. The anxiolytic activity was performed in a stair case model and sedative activity in an open field test. The antagonistic activities were evaluated using naloxone and/or pentylenetetrazole (PTZ). PI-ME was evaluated for prospective anti-allodynic and anti-vulvodynic properties in a rat model of streptozotocin induced neuropathic pain using the static and dynamic testing paradigms of mechanical allodynia and vulvodynia.

Results

GC-MS analysis revealed that PI-ME contained predominant quantities of oleamide (9-octadecenamide), palmitic acid (hexadecanoic acid) and 3-hydroxy-dodecanoic acid, among other active constituents. In the abdominal constriction assay and hot plate test, PI-ME produced dose dependant, naloxone and pentylenetetrazole reversible antinociception suggesting an involvement of opioidergic and GABAergic mechanisms. In the stair case test, PI-ME at 200 mg/kg increased the number of steps climbed while at 600 mg/kg a significant decrease was observed. The rearing incidence was diminished by PI-ME at all tested doses and in the open field test, PI-ME decreased locomotor activity to an extent that was analagous to diazepam. The effects of PI-ME were antagonized by PTZ in both the staircase and open field tests implicating GABAergic mechanisms in its anxiolytic and sedative activities. In the streptozotocin-induced neuropathic nociceptive model, PI-ME (200 and 300 mg/kg) exhibited static and dynamic anti-allodynic effects exemplified by an increase in paw withdrawal threshold and paw withdrawal latency. PI-ME relieved only the dynamic component of vulvodynia by increasing flinching response latency.

Conclusions

These findings suggest that Passiflora incarnata might be useful for treating neuropathic pain. The antinociceptive and behavioural findings inferring that its activity may stem from underlying opioidergic and GABAergic mechanisms though a potential oleamide-sourced cannabimimetic involvement is also discussed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1048-6) contains supplementary material, which is available to authorized users.

Passiflora actinia hydroalcoholic extract and its major constituent, isovitexin, are neuroprotective against glutamate-induced cell damage in mice hippocampal slices

OBJECTIVES

To investigate whether Passiflora actinia hydroalcoholic extract and its major constituent, isovitexin, protect mice hippocampal brain slices from glutamate-induced neurotoxicity.

METHODS

Neuroprotective effect of the extract against glutamate-induced excitotoxicity (10 mm) was evaluated through cell viability of hippocampal slices. The extract or its flavonoids were directly applied to hippocampal slices and then subjected to glutamate-induced toxicity. Alternatively, hippocampal slices from extract-treated mice were also subjected to the same toxicity protocol.

KEY FINDINGS

Mice supplementation with the extract protected hippocampal slices from in-vitro neurotoxicity. When directly applied to hippocampal slices, the extract showed a higher neuroprotective potential than a commercial dry extract of Passiflora incarnata, which was related to P. actinia extract which had higher isovitexin and total flavonoid content expressed as isovitexin. Isovitexin, but not apigenin, induced a similar neuroprotective response when applied alone, at a concentration equivalent to that found in the extract.

CONCLUSIONS

This study highlights new neuropharmacological activity of the Passiflora genus, suggesting that it can act as modulator of the glutamatergic system. The search for improved pharmacotherapies with novel mechanisms of action has been shown of great importance for the treatment of resistant neurological and psychiatric disorders.

Ayurveda and botanical drugs for epilepsy: Current evidence and future prospects

The understanding of epilepsy has progressed since its earliest impression as a disease associated with paranormal and superstitious beliefs. Landmark advances have been made in deciphering the pathophysiological substrates involved in the disease process, and treatment advances have contributed significantly to ameliorating the seizures. However, disease-modifying agents are yet to be discovered. Ayurveda is a system of medicine that stresses a holistic approach to disease, and treatment is focused on disease modification and symptom management. Herbs form the core of Ayurveda medicine; though many of them have been studied for their anticonvulsant activity, very few actually mention the reference of these herbs in Ayurveda literature. Other therapeutic interventions used in Ayurveda are relatively unexplored, and future research will need to focus on this. The current manuscript briefly discusses the understanding of epilepsy as per Ayurveda and reviews herbs that have been studied for their anticonvulsant activity mentioned in Ayurveda literature. This article is part of a Special Issue entitled "Botanicals for Epilepsy".

A model on how to obtain data from botanical practitioners

OBJECTIVE

This paper addresses the challenge on how to obtain information from practitioners with experience in using medicinal plants.

BACKGROUND

Collecting information on medicinal uses of plants is very challenging; since botanical remedies are used within the context of multiple differing medical systems, practitioners differ in training from Western physicians and scientists, and active ingredients of botanicals vary with preparation method, growth, and harvest conditions.

DESIGN/METHODS

A model on how useful data on safety and efficacy can be obtained from botanical practitioners is presented, based on methods developed by the association of anthroposophic physicians in Europe, a system of integrative medicine which includes the use of botanicals and is practiced mostly by medical doctors.

RESULTS

Decades of experience by hundreds of practitioners are summarized and made accessible in a manual, which alphabetically lists the most commonly used botanicals and describes the most successful therapeutic experiences which could be confirmed by several of the contributing practitioners.

CONCLUSIONS/RELEVANCE

This approach of continuous, multilingual systematic collection of successful therapeutic experiences within a community of practitioners with similar goals and a common therapeutic framework can be used not only for the training of successful future botanical practitioners, but also for helping to identify promising botanicals for scientific research and to further their development, and could support their official registration with governing bodies in countries of their use. This article is part of a Special Issue entitled "Botanicals for Epilepsy".

Complex effects of aqueous extract of Melampyrum pratense and of its flavonoids on activity of primary cultured hippocampal neurons

ETHNOPHARMACOLOGICAL RELEVANCE

The aqueous extract of the plant Malmpyrum pratense (Mp), is widely used in traditional medicine as a sedative, yet the biological basis of its action is not known.

AIM OF THE STUDY

The effects of Mp on network activity and intrinsic and synaptic properties were studied in cultured hippocampal neurons in an attempt to analyze its mode of action.

MATERIALS AND METHODS

Dissociated cultures of rat hippocampal neurons were used. Spontaneous network activity was assessed by variations in intracellular [Ca(2+)] concentrations, reflecting action potential discharges. Individual neuronal synaptic activity was measured by patch clamp recordings from similar neurons. The effect of exposure to different concentrations of Mp and some of its main ingredients was measured.

RESULTS

Mp produced complex, dose dependent, reversible effects on network activity, increasing it with low concentrations, and decreasing it at high concentrations. Individual flavonoids contained in Mp mimicked the effects of the extract, both for the facilitating and suppressing effects of the extract. Electrophysiologically, Mp caused a reduction in spontaneous activity, but did not affect membrane properties of individual patch clamped neurons, nor did it affect mEPSCs recorded from these neurons. However, a transient increase in reactivity to pulse application of GABA was evident.

CONCLUSIONS

These results suggest that a main sedative effect of Mp is on GABAergic neurotransmission in cultured hippocampal neurons.

Passiflora incarnata L.: ethnopharmacology, clinical application, safety and evaluation of clinical trials

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Passiflora incarnata Linnaeus comprises approximately 520 species belonging to the Passifloraceae family. The majority of these species are vines found in Central or South America, with rare occurrence in North America, Southeast Asia and Australia. The genus Passiflora incarnata has long been used in traditional herbal medicine for the treatment of insomnia and anxiety in Europe, and it has been used as a sedative tea in North America. Furthermore, this plant has been used for analgesic, anti-spasmodic, anti-asthmatic, wormicidal and sedative purposes in Brazil; as a sedative and narcotic in Iraq; and for the treatment of disorders such as dysmenorrhoea, epilepsy, insomnia, neurosis and neuralgia in Turkey. In Poland, this plant has been used to treat hysteria and neurasthenia; in America, it has been used to treat diarrhoea, dysmenorrhoea, neuralgia, burns, haemorrhoids and insomnia. Passiflora incarnata L. has also been used to cure subjects affected by opiate dependence in India. This review aims to provide up-to-date information about the pharmacology, clinical efficacy and clinical safety of Passiflora incarnata L. based on the scientific literature. In particular, the methodological accuracy of clinical trials is analysed in accordance with current consolidated guidelines on reporting the clinical efficacy of herbal medicine, offering new insight into opportunities for future research and development.

METHODS

A bibliographic investigation was performed by examining the available data on Passiflora incarnata L. from globally accepted scientific databases and search engines (Pubmed, Scopus and Web of Science, SciFinder and Google Scholar). We selected studies, case reports, and reviews addressing the pharmacology and safety of Passiflora incarnata.

RESULTS

Although numerous Passiflora incarnata L. derivative products have been commercialised as alternative anxiolytic and sedative remedies based on their long tradition of use, their supposed efficacy does not appear to be adequately corroborated by the literature, with clinical studies often featuring inadequate methodologies and descriptions of the products under investigation. This medicinal plant has shown a wide spectrum of pharmacological activities in preclinical experiments, including anxiolytic, sedative, antitussive, antiasthmatic, and antidiabetic activities. The plant has a good safety profile. The clinical trials that we included in this review were designed to evaluate and in some cases confirm promising observations of preclinical pharmacological activity, and the methodological limits of these studies are characterised here.

CONCLUSION

In conclusion, clinical studies on the effects of products containing herbal preparations based on Passiflora incarnata reveal crucial weaknesses such as poor details regarding the drug extract ratio, limited patient samples, no description of blinding and randomisation procedures, incorrect definition of placebo, and lack of intention to treat analysis. In conclusion, the results of this review suggest that new clinical trials should be conducted using a more rigorous methodology to assess the traditional putative efficacy of Passiflora incarnata L.

Repeated administration of an aqueous spray-dried extract of the leaves of Passiflora alata Curtis (Passifloraceae) inhibits body weight gain without altering mice behavior

ETHNOPHARMACOLOGICAL RELEVANCE

Passiflora alata is a Southern American species that constitutes many traditional remedies as well as phytomedicines used for sedative and anxiolytic purposes in Brazil. However studies on repeated treatment effects are scarce.

AIM OF THE STUDY

To evaluate behavioral, physiological and biochemical effects of the repeated treatment with an aqueous spray-dried extract of Passiflora alata leaves containing 2.5% (w/v) of flavonoids (PA) in mice.

MATERIAL AND METHODS

Male adult CF1 mice were treated (p.o.) for 14 days with PA (2.5; 25 or 250 mg/kg). The feeding behavior was evaluated at the beginning (1h after the first administration) and at the end of the treatment (15th day). The body weight gain and food consumption were monitored along the days. On day 15 mice were evaluated on plus maze, spontaneous locomotor activity, catalepsy and barbiturate sleeping time tests. Serum glucose, lipids, ALT and AST enzymes were determined. Liver, kidney, perirenal fat, epididymal and peritoneal fat were analyzed.

RESULTS

The repeated treatment with the highest dose tested (250 mg/kg) did not alter the mice behavior on open field, elevated plus maze, catalepsy and barbiturate sleeping time tests. Repeated administration of PA 250 decreased mice feeding behavior and weight gain. PA 25 and PA 250 reduced mice relative liver weight and caused mild hepatic hydropic degeneration as well as a decrease in alanine aminotransferase (ALT) serum level.

CONCLUSIONS

These results indicate that Passiflora alata does not present central cumulative effects and point to the needs of further studies searching for its hepatotoxicity as well as potential anorexigenic.

Cancer-related stress and complementary and alternative medicine: a review

A cancer diagnosis elicits strong psychophysiological reactions that characterize stress. Stress is experienced by all patients but is usually not discussed during patient-healthcare professional interaction; thus underdiagnosed, very few are referred to support services. The prevalence of CAM use in patients with history of cancer is growing. The purpose of the paper is to review the aspects of cancer-related stress and interventions of commonly used complementary and alternative techniques/products for amelioration of cancer-related stress. Feasibility of intervention of several CAM techniques and products commonly used by cancer patients and survivors has been established in some cancer populations. Efficacy of some CAM techniques and products in reducing stress has been documented as well as stress-related symptoms in patients with cancer such as mindfulness-based stress reduction, yoga, Tai Chi Chuan, acupuncture, energy-based techniques, and physical activity. Much of the research limitations include small study samples and variety of intervention length and content. Efficacy and safety of many CAM techniques and some herbs and vitamin B and D supplements need to be confirmed in further studies using scientific methodology. Several complementary and alternative medicine therapies could be integrated into standard cancer care to ameliorate cancer-related stress.

Neuroprotective effects of vitexin, a flavonoid, on pentylenetetrazole-induced seizure in rats

Flavonoids are important constituents of food and beverages and have several neuropharmacological activities. Many of these compounds are ligands for γ-aminobutyric acid type A receptors in the central nervous system. This study aimed to investigate the anticonvulsant effects of intracerebroventricularly administered vitexin (5, 7, 4-trihydroxyflavone-8-glucoside), a flavonoid found in plants, in rats treated with pentylenetetrazole (90 mg/kg, intraperitoneally) and to clarify the underlying mechanism. Vitexin (100 and 200 μm, i.c.v) affected minimal clonic seizures and generalized tonic-clonic seizures induced by pentylenetetrazole by increasing the seizure onset time. Pretreatment with flumazenil suppressed the anticonvulsant effects of vitexin during the onset of both the seizures. These results indicate that vitexin has anticonvulsant effects in the brain, possibly through interaction at the benzodiazepine site of the γ-aminobutyric acid type A receptor complex.

Dual protective effect of Passiflora incarnata in epilepsy and associated post-ictal depression

ETHNOPHARMACOLOGICAL RELEVANCE

Passiflora incarnata L. (Passifloraceae) has been used for the treatment of epilepsy in several traditional systems of medicine.

AIM OF THE STUDY

The aerial parts of Passiflora incarnata contain multiple bioactive metabolites such as, flavonoids (like, chrysin that show CNS depressant activity by agonizing GABA-benzodiazepine receptor), amino acids (like, GABA), harmala alkaloids (reversible monoamine oxidase-A inhibitor), etc. In view of this, the present study was designed to investigate dual protective effect of the hydroethanolic extract of Passiflora incarnata in pentylenetetrazol (PTZ)-induced seizure and associated post-ictal depression.

MATERIALS AND METHODS

Different groups of mice were administered with repeated subconvulsive doses of PTZ (50mg/kg; i.p.) at an interval of 5 days for 15 days. From 5th to 15th day the animals in different groups were administered daily with varying doses of hydroethanolic extract of Passiflora incarnata (150, 300, and 600mg/kg; i.p.), diazepam (2mg/kg; i.p.) and vehicle. On every 5th day, after PTZ treatment, seizure severity (score) was noted. Following convulsive episodes the locomotor activity (using actophotometer) and immobility period (using forced swim test) were also determined. On 15th day after behavioral assessment, the brain serotonin and noradrenaline levels were determined using spectrofluorometric methods.

RESULTS

Treatment with the extract significantly (p<0.05) reduced the seizure severity and immobility period as compared to vehicle control, in a dose and time-dependent manner. Moreover, the extract treatment retained the serotonin and noradrenaline levels of the brain.

CONCLUSIONS

The results of present study concluded that the hydroethanolic extract of Passiflora incarnata suppress PTZ-induced seizures, and ameliorates its associated post-ictal depression, which has been found to be get worsened with the standard antiepileptic drug, diazepam.

Pharmacological studies in an herbal drug combination of St. John's Wort (Hypericum perforatum) and passion flower (Passiflora incarnata): in vitro and in vivo evidence of synergy between Hypericum and Passiflora in antidepressant pharmacological models

Extracts of Hypericum, Passiflora and Valeriana are used for the treatment of mild depression and anxiety. We were interested whether a combination of Hypericum and Passiflora exerts comparable effects to Hypericum alone. We used two well-established models for investigating extracts for their anti-depressant activity, namely the effects on synaptic uptake of serotonin and the forced-swimming-test. We show here for the first time, that Passiflora significantly enhances the pharmacological potency of Hypericum in both models. Our data suggest that anti-depressive therapeutic effects of Hypericum are possible with lower doses, when it is combined with Passiflora, than with mono-preparations of Hypericum.