Antidepressant activity of tricin-7-O-glucoside and anxiolytic-like effect of harmane from Passiflora coriacea Juss. On mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Passiflora coriacea Juss., a medicinal plant in the family Passifloraceae, is widely used to treat anxiety and depression in Mexican folk medicine. However, its chemical profile and biological activity have not been characterized. AIM OF THE STUDY: The aim of the study was to determine the antidepressant activity, anxiolytic effect, and chemical profile of Passiflora coriacea. MATERIALS AND METHODS: An organic fraction (PcEA) from a hydroalcoholic extract of the aerial parts of P. coriacea was obtained, followed by a chemical analysis and separation, yielding six fractions (PcEA, T1, T2, T1.1, T2.1, and T2.2). Male ICR mice were used to determine the antidepressant activity of selected treatments (PcEA, T1, T2, and T1.1) based on a forced swim test (FST). The anxiolytic-like effects of various treatments (PcEA, T1, T2, T2.1, and T2.2) were determined using the elevated plus maze (EPM) test. RESULTS: The organic fraction of P. coriacea decreased anxiety-like behaviors in mice and increased the time of mobility in the FST. After chemical separation, two compounds were isolated from the species with antidepressant activity and anxiolytic-like effects, T1.1 (tricin 7-O-glucoside) and T2.2 (harmane), respectively. CONCLUSIONS: Compounds isolated from P. coriacea exerted anxiolytic and antidepressant effects in mice based on the EPM and FST. The flavonoid tricin-7-O-glucoside and the alkaloid harmane contributed to these biological activities.

Potential anxiolytic therapeutics from Hybanthus enneaspermus (L.) F. Muell. - mitigate anxiety by plausibly modulating the GABAA-Cl- channel.

Anxiety is a commonly prevailing psychological disorder that requires effective treatment, wherein phytopharmaceuticals and nutraceuticals could offer a desirable therapeutic profile. Hybanthus enneaspermus (L.) F. Muell. is a powerful medicinal herb, reportedly effective against several ailments, including psychological disorders. The current research envisaged evaluating the anxiolytic potential of the ethanolic extract of Hybanthus enneaspermus (EEHE) and its toluene insoluble biofraction (ITHE) employing experimental and computational approaches. Elevated Plus Maze, Light and Dark Transition, Mirror Chamber, Hole board and Open field tests were used as screening models to assess the antianxiety potential of 100, 200 and 400 mg/kg body weight of EEHE and ITHE in rats subjected to social isolation, using Diazepam as standard. The brains of rats exhibiting significant anxiolytic activity were dissected for histopathological and biochemical studies. Antioxidant enzymes like catalase, superoxide dismutase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase; and neurotransmitters viz. monoamines (serotonin, noradrenaline, dopamine), Gamma-aminobutyric acid (GABA), and glutamate were quantified in the different regions of rats' brain (cortex, hippocampus, pons, medulla oblongata, cerebellum). Chromatographic techniques were used to isolate phytoconstituents from the fraction exhibiting significant activity that were characterized by spectroscopic methods and subjected to in silico molecular docking. ITHE at 400 mg/kg body weight significantly mitigated anxiety in all the screening models (p < 0.05), reduced the inflammatory vacuoles and necrosis (p < 0.05) and potentiated the antioxidant enzymes (p < 0.05). It enhanced the monoamines and GABA levels while attenuating glutamate levels (p < 0.01) in the brain. Three significant flavonoids viz. Quercitrin, Rutin and Hesperidin were isolated from ITHE. In silico docking studies of these flavonoids revealed that the compounds exhibited substantial binding to the GABAA receptor. ITHE displayed a promising pharmacological profile in combating anxiety and modulating oxidative stress, attributing its therapeutic virtues to the flavonoids present.

Anticonvulsant and anxiolytic-like potential of the essential oil from the Ocimum basilicum Linn leaves and its major constituent estragole on adult zebrafish (Danio rerio).

The Ocimum species present active compounds with the potential to develop drugs for treating chronic disease conditions, such as anxiety and seizures. The present study aims to investigate the anticonvulsant and anxiolytic-like effect of the essential oil from O. basilicum Linn (OEFOb) leaves and its major constituent estragole (ES) in vivo on adult zebrafish (aZF) and in silico. The aZF were treated with OEFOb or ES or vehicle and submitted to the tests of toxicity, open-field, anxiety, and convulsion and validated the interactions of the estragole on the involvement of GABAergic and serotonergic receptors by molecular docking assay. The results showed that the oral administration of OEFOb and ES did not have a toxic effect on the aZF and showed anxiolytic-like effects with the involvement of GABAA, 5-HT1, 5-HT2A/2C and 5-HT3A/3B as well on anxiety induced by alcohol withdrawal. The OEFOb and ES showed anticonvulsant potential attenuating the seizures induced by pentylenetetrazole (PTZ) by modulation of the GABAA system. Both anxiolytic and anticonvulsant effects were corroborated by the potential of the interaction of ES by in silico assay. These study samples demonstrate the pharmacological evidence and potential for using these compounds to develop new anxiolytic and anticonvulsant drugs.

Neuro-stimulating effect of Citri Reticulata Pericarpium Viride essential oil through regulating Glu/NMDAR on olfactory bulb to improve anxiety-like behavior.

ETHNOPHARMACOLOGICAL RELEVANCE: Citri Reticulata Pericarpium Viride (also known Qing-Pi or QP) is a plant in the Rutaceae family, QP is a traditional Qi-regulating medicine in Chinese medicine that is compatible with other Chinese medicine components and has extensive clinical practice in treating anxiety and depression. Reports on the pharmacological effects of QP have demonstrated its neuroprotective effects and antioxidant capacities. Numerous pharmacological benefits of QP are attributed to its antioxidant abilities. Anxiety disorders are a broadly defined category of mental illnesses. Oxidative stress and an imbalance in the antioxidant defense system are typical pathological features of these disorders. AIM OF THE STUDY: The aim of this study was to evaluate the effects of QP essential oil on anxiety using animal models and investigate the underlying neurobiological mechanisms. MATERIALS AND METHODS: This study aimed to develop an animal model of anxiety using chronic restraint stress and investigate the effects of inhalation of Citri Reticulata Pericarpium Viride essential oil on anxiety-like behavior, olfactory function, and olfactory bulb neurogenesis in mice with anxiety. RESULTS: The results showed that long-term chronic restraint stimulation caused a decrease in olfactory function, significant anxiety-like behavior, and a notable reduction in the number of neurons in the olfactory bulb. However, inhalation of Citri Reticulata Pericarpium Viride essential oil reversed these effects, improving the olfactory function, neuro-stimulating effect, alleviating anxiety-like behavior, and regulating theta (4-12Hz) oscillation in the hippocampus DG area. These effects were associated with changes in the expression levels of glutamate receptor NMDAR and NeuN in olfactory bulb. CONCLUSIONS: The study revealed that mice with anxiety induced by chronic restraint stress exhibited significant olfactory dysfunction, providing strong evidence for the causal relationship between anxiety disorders and olfactory dysfunction. Moreover, QP essential oil has the potential to be developed as a therapeutic drug for anxiety disorders, in addition to its role as a complementary anxiolytic.

Unraveling the multi-faceted role of Rosmarinus officinalis L. (rosemary) and diosmetin in managing gut motility.

ETHNOPHARMACOLOGICAL RELEVANCE: Rosmarinus officinalis L. (Rosemary) is a popular herb with reported effectiveness against diarrhea, anxiety and constipation, albeit with limited pharmacological evidence. AIM OF THE STUDY: The current study was aimed at evaluating the therapeutic potential, possible pharmacological mechanisms of action and active constituents of hydro-ethanolic extract of rosemary (Rs.Cr), as potential anti-diarrheal, laxative and anxiolytic agent. METHOD: Rs.Cr was analyzed through reverse-phase high pressure liquid chromatography (RP-HPLC). Laxative, antidiarrheal, and anxiolytic activities were assessed using in vivo models. Spasmogenic and spasmolytic mechanisms were studied on isolated guinea pig ileum and rabbit jejunum tissues, respectively. Possible role of diosmetin, one of the active constituents of Rs.Cr was also evaluated. RESULTS: RP-HPLC analysis revealed presence of diosmetin, rutin and apigenin in Rs.Cr. Laxative effect was seen at low doses, which was partially reversed in atropinized mice. The spasmogenic mechanism was mediated by cholinergic and histaminergic receptors stimulation. At higher doses, antidiarrheal activity was evident, with reduction in gastrointestinal motility and secretions using charcoal meal and enteropooling assays, respectively. Rs.Cr also showed dose-dependent anxiolytic effect. The antispasmodic mechanisms were mediated by anti-muscarinic and K+ channel opening-like effect (predominant KATP-dependent). Diosmetin exhibited antidiarrheal and antispasmodic activities, but spasmogenic effect was not seen. CONCLUSION: Rosemary leaves have dual antidiarrheal and laxative effects, and as well as anxiolytic activity. In addition, the possible modulation of muscarinic and histaminergic receptors, and KATP channels show it as potential herb to be explored for irritable bowel syndrome. Diosmetin is possibly one of its constituents that contributes to its antidiarrheal activity.

Chemical profiling, anticonvulsant and anxiolytic effects of the smoke constituents isolated from Leonotis leonurus (L.) R.Br.

ETHNOPHARMACOLOGICAL RELEVANCE: The use of medicinal plants for central nervous system (CNS)-related ailments, such as epilepsy and anxiety, is prevalent in South Africa. Plants from the Lamiaceae family are commonly used for their therapeutic benefits. Leonotis leonurus (L.) R.Br. has been reported in ethnobotanical literature to have anticonvulsant and anxiolytic effects through the inhalation of pyrolysis products obtained by combustion of the aerial parts. AIM AND OBJECTIVES: To explore the chemical profiles and CNS activity of the smoke extract and isolated constituents of L. leonurus in zebrafish larvae, through anticonvulsive and anxiolytic activity assays. MATERIALS AND METHODS: The smoke extract of L. leonurus was obtained through the combustion of the aerial parts of the plant using a custom-built smoke recovery apparatus. The chemical profile of the smoke constituents was determined using Ultra-Performance Liquid Chromatography coupled with Mass Spectrometry (UPLC-MS). Targeted compounds were subjected to preparative High-Performance Liquid Chromatography for separation before structure elucidation using Nuclear Magnetic Resonance (NMR). The maximum tolerated concentrations, as well as the anxiolytic activity of the smoke extract were determined in five days post fertilisation zebrafish larvae. Reverse-thigmotaxis and locomotor activity of larvae in the light/dark transition assay were used to determine anxiolytic activity. Zebrafish larvae at six days post fertilisation (dpf) were subjected to several concentrations of the smoke constituents of L. leonurus. The baseline locomotor activity of the larvae was tracked for 30 min, prior to addition of pentylenetetrazole (PTZ) to induce seizure-like behaviour in the larvae, after which the locomotor activity of the larvae was once again tracked for an additional 30 min. RESULTS: The UPLC-MS profiles of the smoke extract revealed the presence of two main compounds, leoleorin A and leoleorin B, which were targeted and isolated. Upon subjection to NMR spectroscopy for structure elucidation, the compounds were confirmed to be labdane diterpenoids. Both leoleorin A and leoleorin B, and the smoke extract displayed suppression of the PTZ induced seizure-like behaviour in zebrafish larvae. Under light and dark conditions, the smoke extract and compounds displayed potential anxiolytic activity at different concentrations. CONCLUSION: Our results suggest that the smoke constituents of L. leonurus may exert anticonvulsant and anxiolytic effects which align with the traditional indications and the mode of administration.

Anticonvulsant effects of Cymbopogon giganteus extracts with possible effects on fully kindled seizures and anxiety in experimental rodent model of mesio-temporal epilepsy induced by pilocarpine.

ETHNOPHARMACOLOGICAL RELEVANCE: Epilepsy is a neurological disorder of the brain characterized by periodic and unpredictable occurrence of a transient behavior alteration due to the rhythmic, synchronous and disordered firing of brain neuron. Worldwide, approximately 50 million people currently live with epilepsy and close to 80% of people with epilepsy live in poor countries. However, it was noticed in many countries worldwide that people with epilepsy and their families suffer from stigma and discrimination and that situation exposes them to high psychological conditions such as depression and anxiety as well as more physical problems including bruising and fractures from injuries related to seizures. However, several plants-based products used for epilepsy and anxiety treatments in different system of folk medicine have exhibited a significant anti-epileptic and antianxiety activities using animal models with fewer side effects. AIM OF THE STUDY: The study aimed at evaluating the antiepileptic, status post-epilepticus and anxiolytic effects of Cymbopogon giganteus decoction in rat model induced by pilocarpine. MATERIALS AND METHODS: A total of 90 rats were partitioned into 7 groups and treated as follow: animals of groups I (normal control) and II (considered the negative control) received distilled water (10 mL/kg); while groups III, IV, V, and VI were treated with the C. giganteus extract at 34, 85, 170 and 340 mg/kg p.o, respectively; and the group VII (considered positive control) received sodium valproate at 300 mg/kg, i.p. After 40 min post-treatment, a single dose of n-methyl-scopolamine (1 mg/kg, i.p) was administered to animals of groups (II, III, IV, V, VI, VII) followed by pilocarpine (360 mg/kg, i.p). Animal of group I (normal group) received distilled water. Rats were further observed for 6 h to evaluate the severity and the duration of the acute seizures of epilepsy according to Racine scale. Anxious behavior status post-epilepticus was also assessed in the same rats used above in the Elevated Plus Maze and number of entries into the open or closed arms and the time spent on either open or closed arms of the platform were recorded. Animals were also evaluated on Open Field Test and the number of rearing, crossing, grooming, defecation and center time were registered. RESULTS: C. giganteus decoction significantly (P < 0.05) reduced the animal mortality, the number and duration of convulsions and effectively increased the latency of convulsions. The plant extract significantly (P < 0.05) improved GSH level and SOD activity, reduced MDA and CAT activity, increased GABA level and decreased GABA-t activity in hippocampus. The anxiety induced by pilocarpine was also significantly (P < 0.05) inhibited by the extract of the plant. CONCLUSIONS: Thus, C. giganteus has demonstrated its antiepileptic and anxiolytic activities in rat model and may be used as preventive measure for patients suffering from epilepsy seizures and anxiety.

Antidepressant- and anxiolytic-like activities of Rosmarinus officinalis extract in rodent models: Involvement of oxytocinergic system.

BACKGROUND: Oxytocin (OXT), a neuropeptide involved in mammal reproductive and prosocial behaviors, has been reported to interact with various stressor-provoked neurobiological changes, including neuroendocrine, neurotransmitter, and inflammatory processes. In view of disturbances in psychosocial relationships due to social isolation and physical distancing measures amid the COVID-19 pandemic, being one of the triggering factors for the recent rise in depression and anxiety, OXT is a potential candidate for a new antidepressant. METHODS: In this present study, we have aimed to investigate the effects of oral administration of Rosmarinus officinalis extract (RE), extracted from distillation residue of rosemary essential oil, on central OXT level in the context of other stress biomarkers and neurotransmitter levels in mice models. Tail suspension test (TST) and elevated plus maze test (EPMT) following LPS injection were employed to assess depressive- and anxiety-like behavior in mice, respectively. FINDINGS: Pretreatment with RE for seven days significantly improved behavior in TST and EPMT. Whole-genome microarray analysis reveals that RE significantly reversed TST stress-induced alterations in gene expressions related to oxytocinergic and neurotransmitter pathways and inflammatory processes. In both models, RE significantly increased central Oxt and Oxtr expressions, as well as OXT protein levels. RE also significantly attenuated stress-induced changes in serum corticosterone, brain and serum BDNF levels, and brain neurotransmitters levels in both models. INTERPRETATION: Altogether, our study is the first to report antidepressant- and anxiolytic-like activities of RE through modulating oxytocinergic system in mice brain and thus highlights the prospects of RE in the treatment of depressive disorders of psychosocial nature.

Antidepressant and anxiolytic compounds isolated from Salvia elegans interact with serotonergic drugs.

Salvia elegans belongs to a genus plants with biological activities in central nervous system. In this work, the purpose was to evaluate the anxiolytic and antidepressant effects of fractions and compounds isolated from S. elegans and its interaction with serotoninergic drugs by using behavioral tests in mice. Fractions from aerial parts of S. elegans were obtained by column chromatography, SeF1, SeF2, SeF3, and SeF4. Each of them was administered to 25 mg/k in ICR mice subject to forced swimming test (FST), or elevated plus maze test (EPM), or open field test (OFT). The most active fractions were chemically separated until compounds, which were analyzed as anxiolytic or antidepressant and the coadministration of these treatments with 5-HT1A and 5-HT2 drugs was measured in the different biological tests. All fractions were anxiolytic and antidepressant, oleanolic acid (OA) was found in SeF2, and from SeF3, a mixture of terpenes was found; a GC-MS analysis confirmed the presence of two main compounds: rosifoliol and agaraspirol (TM, mixture of terpenes). TM (doses-response curve, 0.01, 0.1, 0.5, 1.0, and 2.0 mg/kg) and OA (5 mg/kg) were also evaluated demonstrating an antidepressant and anxiolytic effect, respectively. The combination of TM (0.5 mg/kg) with 8-OH (selective 5-HT1A receptor agonist) induced an increment of antidepressant activity, while with the antagonist WAY-100635, the effect diminished. But with DOI (5-HT1c/5-HT2 receptor agonist), there was no change, and with KET (5-HT2 receptor antagonist), the activity was increased. When OA is co-administered with 8-OH or with DOI, the anxiolytic activity of this terpene, diminished; but with the combination with antagonists, the effect of OA shows no change. TM and OA were antidepressant and anxiolytic, respectively, on mice exposed to different tests, and these are able to interact with serotoninergic drugs.

Anxiolytic-like effect of brominated compounds from the marine sponge Aplysina fulva on adult zebrafish (Danio rerio): Involvement of the GABAergic system.

Benzodiazepines are commonly used to treat disorders of the central nervous system, including anxiety. However, due to their adverse effects, there is a continuing interest in discovering new safe and effective drugs. Marine natural products have emerged as a prolific source of bioactive nitrogenated compounds. Aiming to discover new biologically active natural compounds, the marine sponge Aplysina fulva, a nitrogen-bearing heterocyst producer, was investigated. The main isolated compounds (4, 6, and 9) were evaluated on adult zebrafish (Danio rerio). A group of fishes (n = 6) was preliminarily subjected to acute toxicity, and open field tests using 0.1, 0.5, and 1.0 mg/mL (v. o.) of those compounds was performed. The anxiolytic effect was further investigated in the light/dark assay based on the locomotor response at zebrafish. Interactions through the GABAergic system were investigated using flumazenil, a silent modulator of GABA receptors. To improve the results, a study of molecular docking using the GABAA receptor also was performed. Based on the results, the bromotyrosine derivative compounds 4, 6, and 9 exhibited anxiolytic-like effects mediated by the GABAergic system.

Coumarins from Seseli devenyense Simonk.: Isolation by Liquid-Liquid Chromatography and Potential Anxiolytic Activity Using an In Vivo Zebrafish Larvae Model.

Different types of anxiety disorders have become the number one mental health issue in developed countries. The search for new, safer and effective drug-like molecules among naturally derived substances faces two difficulties: an efficient method of isolation compounds with a high-purity and high-throughput animal model for activity assay. Thus, the aim of the present study was to isolate by liquid-liquid chromatography high-purity rare coumarins from the fruits of Seseli devenyense Simonk. and evaluate their anxiolytic effect (defined as reversed thimotaxis) using a 5-days post-fertilization (dpf) Danio rerio larvae model. Liquid-liquid chromatography enabled the isolation of one simple hydroxycoumarin (devenyol) and four pyranocoumarins (cis-khellactone, d-laserpitin, isolaserpitin and octanoyllomatin). The anxiolytic effect was defined as a decrease in the time spent in the boundaries of the living space (also described as reversed thigmotaxis). Our results show that all isolated courmarins exerted a significant influence on the anxiety behavior (anxiolytic activity) in the zebrafish larvae model. According to our knowledge, this is the first report of anxiolytic activity of pyranocoumarins and devenyol.

Exposure to noise augments behavioral deficits in mice: Protective effect of banana peel extract.

The study is aimed to evaluate the protective impact of banana peel extract (BPE) following noise induce behavioral deficits in male mice. Animals were separated into two groups (control and test, 12 in each). Control mice were given drinking water, at the same time test group was given BPE (400 mg/kg; oral administration). Animals have received their respective treatment for 14 days. Mice were subdivided (n=6) into unstressed and stressed groups on day 15. Noise stress was given to the respective group for 4-h. Behavioral activities were monitored 24-h after the 4-h noise stress. Forced-swim-test, Elevated-plus-maze and light-dark-activity-box tests were performed for depression/anxiety-like behaviors respectively. Morris-water-maze assessment was used for memory. After behavioral tests animals were sacrificed and brain was detached for biochemical estimations and histopathological studies. In the present study, BPE produced anxiolytic and antidepressant-like effects and enhanced memory. Activity of antioxidant enzymes increased while levels of AChE and MDA decreased in BPE treated animals. Histopathological alterations induced by noise stress were also normalized by BPE. It is concluded that supplementation/administration of banana peel has preventive effects against anxiety, depression and memory impairment via its strong antioxidant potential following NS.

Calea zacatechichi Schltdl. (Compositae) produces anxiolytic- and antidepressant-like effects, and increases the hippocampal activity during REM sleep in rodents.

ETHNOPHARMACOLOGICAL RELEVANCE: Calea zacatechichi is a plant with an extensive popular and ritual use in Mexico. In healthy volunteers, it induces well-being and tranquility senses, and facilitates superficial stages of sleep. However, anxiolytic, and antidepressant-like effects and changes on the sleep-waking stages have not been explored. AIM: To determine anxiolytic and antidepressant-like effects of an aqueous extract of C. zacatechichi (CZ) in rodents and to analyze their effects on hippocampal activity in the rat sleep-waking cycle. MATERIAL AND METHODS: CZ anxiolytic- and antidepressant-like effects were evaluated in several mice and rat behavioral paradigms. CZ effects on temporal distribution of sleep were described, and hippocampus EEG frequency patterns were analyzed during the sleep-waking cycle; absolute and relative powers were analyzed during Rapid Eye Movements (REM) and non-REM sleep stages. CZ chemical analysis was performed by UPLC-ESI-MS. RESULTS: CZ produced specific and robust anxiolytic- and antidepressant-like effects in mice and rats, similar to those of prototypical drugs, at doses ranging from 0.5 to 50 mg/kg. CZ at 100 mg/kg produced visible mild sedative effects in rats, associated with a significant increase in Slow Wave Sleep episodes during a 6 h recording, and enhanced fast frequencies of hippocampus (gamma-band:31-50 Hz) during REM sleep. CONCLUSION: Results could support the well-being and tranquility senses reported by healthy consumers, and to explain the oneiric content during dreams and some improvements in cognitive processes described by consumers. Anxiolytic- and antidepressant-like effects of this species, reported for first time in this study could improve some aspects of mental health.

Anxiolytic effect of an extract of Salvia miltiorrhiza Bunge (Danshen) in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Salvia miltiorrhiza Bunge (Danshen), a traditional Chinese medicine, has demonstrated in modern studies for its pharmacological activities in treatments of CNS disorders like insomnia, dysphoria. However, its application on anxiolytic effect from the ethanol extract of Salvia miltiorrhiza Bunge (SMEtOH) has not yet been reported. MATERIALS AND METHODS: This study investigated the anxiolytic effect of the SMEtOH using the elevated plus-maze test (EPM) and the hole-board test (HBT) with diazepam and buspirone as positive controls. Also, the spontaneous locomotor activity of mice had been investigated in the open field. Further, we have illustrated the anxiolytic mechanisms of SMEtOH with its influencing upon GABAergic and/or serotonergic nervous systems via a method that SMEtOH was co-administered with flumazenil, a benzodiazepine (BZD) antagonist, or a drug (WAY-100635), a selective 5HT1A receptor antagonist. RESULTS: In hole-board test, results presented that SMEtOH increased head-dip counts and duration time. On the other hand, a decrease in spontaneous locomotor activity was observed. In the EPM test, SMEtOH increased the percentage of open-arm entries and the percentage of time spent in open arms. However, when SMEtOH co-administered with flumazenil or WAY-100635, the anxiolytic effect of SMEtOH was significantly counteracted. CONCLUSION: From these results, we can conclude that the anxiolytic mechanism of SMEtOH is exerted through an activation of the BZD and 5HT1A receptors.

An Insight Into the Anxiolytic Effects of Lignans (Phyllanthin and Hypophyllanthin) and Tannin (Corilagin) Rich Extracts of Phyllanthus amarus : An In-Silico and In-vivo approaches.

The extracts and the compounds isolated from Phyllanthus amarus Schumm and Thonn (Family: Euphorbiaceae) have shown a wide spectrum of pharmacological activities including antiviral, antibacterial, antiplasmodial, antimalarial, antimicrobial, anticancer, antidiabetic, hypolipidemic, antioxidant, hepatoprotective, nephroprotective and diurectic properties. BACKGROUND: This investigation was aimed at exploring the anxiolytic potential of Phyllanthus amarus standardized extracts and predict probable role of marker phyto constitutents. OBJECTIVE AND METHODS: Three standardized extracts of Phyllanthus amarus plant viz. standardized aqueous extract of Phyllanthus amarus whole plant (PAAE), standardized methanolic extract of P. amarus leaf (PAME) and the standardized hydro-methanolic extract of P. amarus leaf (PAHME) were tested in the classical animal models of anxiety: Elevated plus-maze model and Light & Dark Exploration test. RESULTS: The lower doses of the tannin rich extract (PAHME) of the P. amarus possess significant anxiolytic activity compared to lignin rich (PAME) and aqueous extracts (PAAE), while at a higher dose (400mg/kg) the results of all three extracts appears to be potentially sedative. While the molecular docking studies support these probable anxiolytic, the sedative effects of the Phyllanthus amarus extracts could be due to the interaction of tannins and lignans with the GABAbenzodiazepine receptor complex. CONCLUSION: The results of the present study indicate that the tannin-rich extract of the P. amarus may have potential clinical applications in the management of anxiety. It can be further studied for optimum dosage to be used as a future of anti-anxiety drug development or as a standardized Phytomedicine.

Discovery and proteomics analysis of effective compounds in Valeriana jatamansi jones for the treatment of anxiety.

ETHNOPHARMACOLOGICAL RELEVANCE: Zhizhu Xiang (ZZX for short) is the root and rhizome of Valeriana jatamansi Jones, which is a Traditional Chinese Medicine (TCM) used to treat various mood disorders for more than 2000 years, especially anxiety. However, there have been few investigations to clarify the compounds in ZZX for the treatment of anxiety. AIM OF THE STUDY: Our previous study has identified five anti-anxiety components, including hesperidin, isochlorogenic acid A, isochlorogenic acid B and isochlorogenic acid C and chlorogenic acid, from extract of ZZX. In order to find the optimal combination and the underlying mechanism of these five components in the treatment of anxiety disorder, researches were designed based on uniform design method and proteomic technology. MATERIALS AND METHODS: The samples with different proportion and content of the five active components were arranged by uniform design method. Then a mathematical model was formulated using partial least square method and stepwise regression analysis. Moreover, the empty bottle stress-induced anxiety rat model was established, and the anti-anxiety effect was recorded by the unconditioned reflex elevated maze test and the open field test. In addition, the isobaric tags for relative and absolute quantitation (iTRAQ) technique, along with the multidimensional liquid chromatography and high-resolution mass spectrometry were applied in proteomic study. At last, the result of proteomic analysis was further confirmed by Western blot. RESULTS: The optimal combination of the components from the extract of ZZX was 1.153 mg/kg hesperidin, 2.197 mg/kg Isochlorogenic acid A, 0.699 mg/kg Isochlorogenic acid B and 1.249 mg/kg Chlorogenic acid. Total 6818 proteins were identified using proteomic analysis and 80 differentially expressed proteins were used for further bioinformatic analysis. These proteins were involved in the neuroactive ligand-receptor interaction, protein digestion and absorption, cholesterol metabolism, Chagas disease, and AGE/RAGE signaling pathway. CONCLUSIONS: The composition and proportion of anti-anxiety components in extract of ZZX was disclosed, and there was an anti-anxiety effect for the combined components of flavonoids and phenolic acids. Through proteomic analysis and Western blot, it was found that the effective components of extract of ZZX can exert synergistic anti-anxiety effects via the regulation of multi-signaling pathways. These findings could provide a preliminary research basis for the development of new low-toxic, efficient, stable and controllable anti-anxiety drugs.

Pharmacological basis of the anxiolytic and antidepressant properties of Silexan®, an essential oil from the flowers of lavender.

Silexan®, a proprietary essential oil manufactured by steam distillation from Lavandula angustifolia flowers showed pronounced anxiolytic effects in patients with subthreshold anxiety disorders and was also efficacious in patients with Generalized Anxiety disorder (GAD). Moreover, evidences for antidepressant-like properties of Silexan® have been observed in anxious patients suffering from comorbid depressive symptoms and in patients with mixed anxiety-depression disorder (ICD-10 F41.2). In accordance with the clinical data Silexan® is active in several behavioral models in rodents at rather low concentrations indicating potent anxiolytic and antidepressive properties. As possible mechanism of action a moderate inhibition of voltage dependent calcium channels (VDCC) has been found showing some similarities to the anxiolytic drug pregabalin. However, while pregabalin mainly inhibits P/Q-type channels by binding to a modulatory subunit, Silexan® moderately inhibits mainly T-type and N-type channels and to some extent P/Q-type channels. Unlike pregabalin Silexan® is free of hypnotic or sedative side effects and seems to be devoid of any abuse potential. With respect to its specific antidepressant like properties Silexan® improves several aspects of neuroplasticity which seems to be the common final pathway of all antidepressant drugs. As a potential mechanism of its effects on neuroplasticity an activation of the transcription factor CREB via activation of intracellular signaling kinases like PKA and MAPK has been found. Since the concentrations of Silexan® needed to inhibit VDCC function and to improve neuroplasticity are quite similar, the effects of Silexan® on PKA or MAPK could constitute a common intracellular signaling cascade leading to VDCC modulation as well as CREB activation and improved neuroplasticity.

Health policy versus kava (Piper methysticum): Anxiolytic efficacy may be instrumental in restoring the reputation of a major South Pacific crop.

ETHNOPHARMACOLOGICAL RELEVANCE: Kava (Piper methysticum G. Forst. f.) is by far the most important plant used in the islands of Melanesia, Polynesia and Micronesia for its relaxing effects. Kava drinking is a pillar of South Pacific societies and is also the foundation of their economies. Preparations of kava extract as herbal medicinal drugs were banned in Germany in 2002 and again in 2019, with dramatic consequences for the South Pacific economies. In 2002, the major regulatory argument for the ban of kava was safety issues. In 2019, the assessment report of the European Medicines Agency's Herbal Medicinal Product Committee (HMPC) justified a negative benefit-to-risk ratio by a supposed lack of efficacy of ethanolic extracts for an indication of which kava extract preparations never had an approval. In this HMPC report the efficacy in the approved indications 'nervous anxiety, tension and restlessness' was attributed to the extract branded as 'WS 1490', which was assumed to have been prepared with acetone as an extraction solvent. In addition to this change of indication and the attribution of efficacy to acetone kava extract alone, the German health authorities and the HMPC still refuse to discuss quality issues as a likely factor impacting drug safety. The first case reports of liver toxicity were observed with an acetone extract in a timely relationship with the introduction of 'two-day kava' instead of 'noble kava' as used in ethanolic kava extracts. AIM OF THE STUDY: The correlation between clinical benefits and the type of extract preparation was examined. METHODS: In order to identify the types of kava material and extracts used in clinical trials, the respective publications were compared with regulatory databases and protocols of a German regulatory advisory board. RESULTS AND CONCLUSIONS: The comparison reveals inconsistencies in the regulatory decisions. In all studies with WS 1490, the evidence points to the use of an ethanolic extract. The efficacy of kava extract for the approved indication was clearly demonstrated. The HMPC report and the recent renewed German regulatory ban of kava therefore require major revision, which should include the impact of the use of "two-day kava" on drug safety. Such a revision could contribute to restoring the reputation of "noble kava" on the international markets.

Pharmacological and pharmacokinetic effect of a polyherbal combination with Withania somnifera (L.) Dunal for the management of anxiety.

ETHNOPHARMACOLOGICAL RELEVANCE: In the Indian system of medicine, Withania somnifera (L.) Dunal, Hemidesmus indicus (R.Br.), Aegle marmelos (L.) Correa, Emblica officinalis Gaertn, Ocimum sanctum (L.) has been mentioned as a remedy for the treatment of anxiety related disorders. Based on their folklore use, a polyherbal combination was derived for the management of anxiety. AIM OF THE STUDY: The present study is aimed to find the best polyherbal combination (PHC), in terms of its pharmacological action, out of two PHC, namely PHC1 and PHC3, prepared based on the previous studies conducted and to carry out the pharmacokinetic (PK) study of the best combination (PHC3). MATERIALS AND METHODS: Pharmacological activities include elevated plus maze model and hole-board test for anti-anxiety screening, gamma amino-butyric acid (GABAA) measurement in brain tissues and superoxide dismutase, lipid peroxidation and reduced glutathione measurement for anti-oxidant screening. RESULTS: PHC3 (100 mg/kg) produced statistically significant (p < 0.05) effect on all the pharmacological outcome measures when compared to alprazolam standard. Therefore, it was chosen for PK study. PK study was carried out using Liquid Chromatography Mass Spectroscopy technique with respect to Withaferin-A. PK parameters such as maximum plasma concentration (Cmax), 16.78 ± 5.32 ng/mL; time of maximum concentration (Tmax), 18 ± 0.12min; half-life (T1/2) 61.20 ± 9.87min; mean residual time (MRT), 7.53 h s; area under the concentration versus time curve (AUC0-1), 1678 ± 34.13 ng/mL; area under the concentration versus time curve from zero to infinity (AUC0-∞), 1705 ± 28.87 ng/mL; total clearance (CL), 290.67 ± 15.89 mL/min and volume of distribution (Vd) 0.054 L were calculated. CONCLUSIONS: The results of the studies revealed that PHC3 possessed significant anxiolytic, anti-oxidant activities and enhanced expression of GABAA mediated inhibition when compared to PHC1. Withaferin-A in PHC3 exhibited a rapid oral absorption in rat plasma. The findings of this study greatly help to provide useful evidence for the development of suitable formulation using PHC3.

In vivo anxiolytic and in vitro anti-inflammatory activities of water-soluble extract (WSE) of Nigella sativa (L.) seeds.

The WSE is a highly polar, gummy and mucilaginous bioactive content of the Nigella sativa (L.) seeds. This study reports the anxiolytic and anti-inflammatory effects of WSE investigated using Elevated Plus Maze (EPM) and Hole-Board Test (HBT) in adult mice and human RBCs haemolysis inhibition and protein denaturation respectively. The oral WSE treatment (100 & 200 mg/kg b.w/day) for 72 hours has exhibited slightly better anxiolytic effect (p < 0.05) through the time span (92.33 & 93.33 s) spent in the opened arms of EPM vs. diazepam (1 mg/kg b.w i.p/day; 69.33 s). In HBT, only WSE (200 mg/kg b.w/day) has shown a promising number of mean head pokes (13.27 times/min) vs. diazepam (12.87 times/min). The WSE (62.5-500 µg/mL) exposure has exhibited 40.14-72.18% protection against lysis of RBCs vs. aspirin (57.04-71.48%) whilst 62.67-67.66% inhibition of protein denaturation vs. diclofenac sodium (43.11-80.64%). The current findings suggested WSE has promising anxiolytic and anti-inflammatory activities.