Anxiolytic and antidepressant-like effects ofFerulago angulataessential oil in the scopolamine rat model of Alzheimer's disease

Antioxidant Compounds in the Treatment of Alzheimer's Disease: Natural, Hybrid, and Synthetic Products

Alzheimer's disease (AD) which is associated with cognitive dysfunction and memory lapse has become a health concern. Various targets and pathways have been involved in AD's progress, such as deficit of acetylcholine (ACh), oxidative stress, inflammation, β-amyloid (Aβ) deposits, and biometal dyshomeostasis. Multiple pieces of evidence indicate that stress oxidative participation in an early stage of AD and the generated ROS could enable neurodegenerative disease leading to neuronal cell death. Hence, antioxidant therapies are applied in treating AD as a beneficial strategy. This review refers to the development and use of antioxidant compounds based on natural products, hybrid designs, and synthetic compounds. The results of using these antioxidant compounds were discussed with the given examples, and future directions for the development of antioxidants were evaluated.

Current Knowledge of the Antidepressant Activity of Chemical Compounds from Crocus sativus L

Psychotropic effect of Crocus sativus L. (family Iridaceae) biologically active chemical compounds are quite well documented and they can therefore be used in addition to the conventional pharmacological treatment of depression. This systematic review on antidepressant compounds in saffron crocus and their mechanisms of action and side effects is based on publications released between 1995−2022 and data indexed in 15 databases under the following search terms: antidepressant effect, central nervous system, Crocus sativus, cognitive impairement, crocin, crocetin, depression, dopamine, dopaminergic and serotonergic systems, picrocrocin, phytotherapy, neurotransmitters, safranal, saffron, serotonin, and biologically active compounds. The comparative analysis of the publications was based on 414 original research papers. The investigated literature indicates the effectiveness and safety of aqueous and alcoholic extracts and biologically active chemical compounds (alkaloids, anthocyanins, carotenoids, flavonoid, phenolic, saponins, and terpenoids) isolated from various organs (corms, leaves, flower petal, and stigmas) in adjuvant treatment of depression and anxiety. Monoamine reuptake inhibition, N-methyl-d-aspartate (NMDA) receptor antagonism, and gamma-aminobutyric acid (GABA)-α agonism are the main proposed mechanism of the antidepressant action. The antidepressant and neuroprotective effect of extract components is associated with their anti-inflammatory and antioxidant activity. The mechanism of their action, interactions with conventional drugs and other herbal preparations and the safety of use are not fully understood; therefore, further detailed research in this field is necessary. The presented results regarding the application of C. sativus in phytotherapy are promising in terms of the use of herbal preparations to support the treatment of depression. This is particularly important given the steady increase in the incidence of this disease worldwide and social effects.

Effect of intensive olfactory training for cognitive function in patients with dementia

AIM

Recent evidence has revealed an association between neurodegenerative disorders and olfactory dysfunction. However, whether olfactory training can improve cognitive impairment in patients with dementia requires further study. The present study aimed to resolve this by developing an intensive olfactory training (IOT) protocol and assessing its impact on each of the cognitive domains in patients with dementia.

METHODS

Patients were prospectively recruited between June 2020 and September 2020. Baseline evaluations included demographic data, olfactory function test, depression scale and detailed cognitive function tests. Thirty-four patients in the experimental group underwent IOT twice a day with a 40-odor set for 15 days, while 31 individuals in the control group received conservative management. Follow-up evaluations using the depression scale and detailed cognitive function tests were performed after IOT.

RESULTS

Baseline characteristics were not different between the two groups. The IOT group showed significant improvements in depression, attention, memory and language functions, but not global cognition, frontal executive, or visuospatial functions compared with the control group.

CONCLUSION

This study shows the ability of IOT to alleviate depression and improve some cognitive functions in patients with dementia. These results suggest that IOT may be an effective non-pharmacological approach for improving the symptoms of dementia. Geriatr Gerontol Int ••; ••: ••-•• Geriatr Gerontol Int 2021; ••: ••-••.

Satureja montana L. essential oil various dosages effect on the main rats’ biological features

An application of natural antioxidants remains the focus of research groups. The effect of Satureja montana L. essential oil in various doses on the main biological characteristics of Wistar rats was the main aim of the study. The intensification of protein metabolism in the blood plasma of rats on the background of the use of Satureja montana L. essential oil was noted. Total protein increases by 17.9 – 19.7%, and albumin by 27.6% in rats of the experimental group received the essential oil at a dose of 0.6 ml per kg of feed. A significant increase in the AST level in control group rats to 207.3 U.L-1 was revealed. Its one to a certain extent indicates the hepatoprotective effect of mountain savory oil and a decrease in inflammatory processes in the organs of the gastrointestinal tract in the conditions of cell maintenance of rats of the experimental groups. Gastric epithelium thickness of rats of both experimental groups was lower than the control animals. But it did not bear any signs of atrophy. The difference of this indicator in comparison with control was 12.75 μm (p ≤0.05) in the second group and it was reliable. The number of chief stomach cells increases in animals of the experimental groups, which may indicate a greater enzymatic activity. An increased dose of mountain savory oil contributes to the formation of more damage to hepatocytes on the periphery of the liver lobule. Thus, the relationship between liver enzymes and the state of peripheral hepatocytes was noted.

Effects of olfactory stimulation on cognitive function and behavior problems in older adults with dementia: A systematic literature review

The aim of this study was to examine the effects of olfactory stimulation on both cognitive and behavioral symptoms in neurodegenerative diseases. The criteria for selection of participants in the study included neurodegenerative disease, interventions using olfactory stimulation, and measured cognitive or psychological symptoms. 5301 articles were identified, excluding duplicate papers. Seven original articles were selected according to the full article review and eligibility criteria. The final selected studies were all quasi-experimental studies and were published between 2002 and 2015. To assess the risk of bias, we used Cochrane Collaboration's tool, Non-randomized Studies-of Interventions (ROBINS-I). Although olfactory stimulation reported various effects on behavioral and psychological symptoms, it is still in its infancy. We propose standardization of olfactory stimulation and olfactory training. In patients with neurodegenerative diseases, it is necessary to consider the symptoms and severity of olfactory stimulation.

Essential Oil from the Leaves of Chromolaena odorata, and Sesquiterpene Caryophyllene Oxide Induce Sedative Activity in Mice

Chromolaena odorata (L.) R.M.King & H.Rob. essential oil (COEO) was investigated for its sedative activity in mice. The results showed that COEO significantly reduced mice locomotor activity and the most efficient concentrations were 0.04 and 0.00004 mg/cage (volume of the cage 61.2L). Analysis of chemical composition of the oil indicated that caryophyllene oxide (43.75%) was the major compound and bioactivity-guided fractionation of the oil was performed to isolate the compound responsible for activity. The data clearly identified sesquiterpene caryophyllene oxide as the compound inducing COEO sedative activity and it was effective in decreasing mice locomotor activity by 56% and 57% at 0.0004 and 0.04 mg/cage, respectively. In order to understand the action mechanisms, caryophyllene oxide was tested for its effects on the central nervous system (CNS) by using a caffeine pre-excited mice test and a pentobarbital sleeping-induced test in mice. The results showed that caryophyllene oxide is a potent CNS depressant. Nevertheless, it fails to potentiate the effects of pentobarbital on the GABAergic system, nor did flumazenil, a GABA_A receptor antagonist, reversed its effects. It was especially interesting to note that β-caryophyllene, the precursor of caryophyllene oxide, demonstrated a similar pattern of sedative activity, and the present work further extends actual knowledge on these naturally occurring sesquiterpenes. The findings in this study reveal the new activity of caryophyllene oxide as an innovative way to manage sleep and CNS-related disorders, and demonstrates a satisfactory effect of two interesting sesquiterpene compounds on the CNS.

The ethnobotany, phytochemistry and biological properties of genus Ferulago - A review

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Ferulago, belonging to the Apiaceae family, is found mainly in the Mediterranean area, Southwest and Middle Asia, the Caucasus and North Africa. Since ancient times, species of this genus have been largely employed in traditional medicine for their biological properties such as antimicrobial, anti-inflammatory, antispasmodic, insecticidal, and anti-malaria, cholinesterase inhibition effects, etc. AIMS: The scope of this paper is to present a comprehensive respect review of this interesting genus including traditional uses, chemical composition of volatile and non-volatile metabolites, and in vitro and in vivo biological properties either utilizing the crude extracts or essential oils, or the single isolated compounds. Furthermore, critical considerations of the published data have been highlighted by comparing them with the results obtained from species of other genus belonging to the Apiaceae family.

MATERIALS AND METHODS

The available information on these genera was collected from scientific databases and cover from 1967 up to 2020. The following electronic databases were used: PubMed, SciFinder, Science Direct, Scopus, Web of Science and Google Scholar. The search terms used for this review included Ferulago, all the botanical names of the species, both accepted names or synonyms, essential oils, volatile components, traditional uses, activity, pharmacology, and toxicity. No limitations were set for languages. A total of 230 articles were included in the present review.

RESULTS

Researches performed on either crude extracts, solvent fractions or isolated pure compounds from species of genus Ferulago showed several biological properties such as antibacterial, antifungal, antioxidant, antidiabetic, enzymatic, cytotoxic, anticancer, hepatoprotective, nephroprotective, antileishmanial, antimalarial, anticoagulant, anti-inflammatory, insecticidal, etc. Activities. Phytochemical investigations of Ferulago species have revealed that coumarins are the main constituents of the genera. A large number of flavonoids, terpenoids and other metabolites were also identified. Furthermore, a complete review on the essential oil composition of all the taxa studied so far has been also included.

CONCLUSION

In the present study, we have provided scientific information and research developments on traditional uses, phytochemical profiles, biological activities and industrial practices on the Ferulago genus. The commercial use and the applications in agri-food sector of some of these species have been also considered. In fact, the various extracts and essential oils have been used as antioxidants and/or as antimicrobial agents, for the stabilization of sunflower and soybean oil, for food packagings, as antioxidants of mayonnaise and yogurt during their storage and, also, as economically valid source for obtaining single compounds, more expensive at a synthetic level.

The phytochemistry and biological diversity of Ferulago genus (Apiaceae): a systematic review

OBJECTIVES

The genus Ferulago belonging to the family Apiaceae is a flora widely distributed in Central Asia and the Mediterranean and used in folk medicine. It is administered as a sedative, tonic, digestive, aphrodisiac, also as a treatment for intestinal worms and haemorrhoids. Herein, we reported a review on phytochemistry and its biological activities reported from 1990 up to early 2020. All the information and reported studies concerning Ferulago plants were summarized from the library and digital databases (e.g. Scopus, Medline, Scielo, ScienceDirect, SciFinder and Google Scholar).

KEY FINDINGS

The phytochemical investigations of Ferulago species revealed the presence of coumarins as the main bioactive compounds, including daucane derivatives, sesquiterpenes aryl esters, phenol derivatives, flavonoids and essential oils. Moreover, the therapeutic potentials of the pure compounds isolated from the genus Ferulago possess promising properties namely anticholinesterase, antimicrobial, anticoagulant, antileishmanial, antioxidant, antibacterial and antiproliferative.

SUMMARY

Today, significant advances in phytochemical and biological activity studies of different Ferulago species have been revealed. The traditional uses and reported biological results could be correlated via the chemical characterization of these plants. All these data will support the biologists in the elucidation of the biological mechanisms of these plants.

Role of Ascaridole and p-Cymene in the Sleep-Promoting Effects of Dysphania ambrosioides Essential Oil via the GABAergic System in a ddY Mouse Inhalation Model

The essential oil obtained from Dysphania ambrosioides leaves (DAEO) has antifungal, antioxidant, and antimicrobial properties. This study investigated DAEO's chemical composition and its sleep-promoting effects via administration by inhalation in ddY mice. Ascaridole (35.5%) and p-cymene (47.2%) were the major components. To obtain insight into DAEO's effects on the central nervous system (CNS), ascaridole and p-cymene were evaluated for sedative activity by using the caffeine-treated excitatory mouse model. DAEO administration significantly decreased locomotor activity at all doses except 0.000 04 mg per 400 μL of triethyl citrate. Both ascaridole and p-cymene were highly effective in decreasing locomotor activity of excited mice by more than 50%. In addition, ascaridole and p-cymene prolonged the pentobarbital-induced sleeping duration by 42% and 77%, respectively. These effects were antagonized by coadministration of gamma-aminobutyric acid (GABA_A)-benzodiazepine receptor antagonist, flumazenil (3 mg/kg), indicating that the GABAergic system mediates the sedative effect. Finally, inhaled ascaridole and p-cymene had no negative effect on motor coordination, as observed during the Rota-rod test. Therefore, via activation of the GABAergic system, ascaridole and p-cymene mediate the sleep-promoting effect of DAEO. The results further extend the knowledge on their use as potential promising natural products for the management of sleep disorders and CNS-related ailments.

Dose-related effects of inhaled essential oils on behavioural measures of anxiety and depression and biomarkers of oxidative stress

ETHNOPHARMACOLOGICAL RELEVANCE

Essential oils (EOs) are extracts of organic, volatile metabolites of plants that are typically oily liquids at ambient temperatures. Inhalation of EOs can regulate brain health and functions associated with mood and neurodegeneration, reflecting their bioavailability to brain. The aim was to identify physicochemical properties that influenced EO volatility and pathways of brain uptake by inhalation.

MATERIALS AND METHODS

Dose-dependency of effects, determined as: total EO intake (μg/g bodyweight-BW), and rate of EO intake (μg/hr/g-BW), was determined by meta-analysis of data from animal studies (10 studies, 12 EOs), measuring effects on anxiety, depression and selected biomarkers of oxidative stress and inflammation (OSI).

RESULTS

Results demonstrated benefits on animal behavior at EO intakes of 1-100 μg/g BW and 1-10 μg/hr/g BW (Elevated Plus Maze and Forced Swimming tests) and <100 μg/g BW and 10-100 g/hr/g BW (Marble Burying). EOs regulated OSI biomarkers at intakes of 10-100 μg/g BW and 1-10 μg/h/g BW, and a dose-dependent elevation of dopamine at >1000 μg/g BW and 100-1000 μg/hr/g BW.

CONCLUSION

The results support that EO 'aromatherapy' can promote dose-dependent regulation of anxiety, depression and OSI and that efficacy requires optimization of dose.

Anxiolytic Effect of Essential Oils and Their Constituents: A Review

Essential oils are usually used in aromatherapy to alleviate anxiety symptoms. In comparison to traditional drugs, essential oils have fewer side effects and more diversified application ways, including inhalation. This review provides a comprehensive overview of studies on anxiolytic effects of essential oils in preclinical and clinical trials. Most of the essential oils used in clinical studies have been proven to be anxiolytic in animal models. Inhalation and oral administration were two common methods for essential oil administration in preclinical and clinical trials. Massage was only used in the clinical trials, while intraperitoneal injection was only used in the preclinical trails. In addition to essential oils that are commonly used in aromatherapy, essential oils from many folk medicinal plants have also been reported to be anxiolytic. More than 20 compounds derived from essential oils have shown an anxiolytic effect in rodents, while two-thirds of them are alcohols and terpenes. Monoamine neurotransmitters, amino acid neurotransmitters, and the hypothalamic-pituitary-adrenal axis are thought to play important roles in the anxiolytic effects of essential oils.

Evaluation of antiamnesic activity of Salvia multicaulis essential oil on scopolamine-induced amnesia in rats: in vivo and in silico approaches

Plants of genus Salvia have been used in folk medicine for wound healing, in the alleviation of stomach, liver, and rheumatism pains, as antioxidant, cognitive-enhancer, sedative and antiseptic, stimulant and tonic agents. The present study aimed to evaluate whether Salvia multicaulis essential oil (1% and 3%) administered for 21 days attenuates cognitive deficits and exhibits anxiolytic and antidepressant-profile in the scopolamine-induced amnesia in rats. Rats were randomly divided into six groups (n = 6): (1) control, (2) scopolamine (Sco, 0.7 mg/kg) (3, 4) S. multicaulis essential oil treatment groups (SEO, 1% and 3%), (5) diazepam (DIAZ, 1.5 mg/kg) and (6) tramadol (TRM, 10 mg/kg). To establish an animal model of amnesia, Sco (0.7 mg/kg), a muscarinic acetylcholine receptor antagonist, was injected into male Wistar rats. Y-maze (memory), radial arm-maze (memory), elevated plus-maze (anxiety), and forced swimming (depression) tests were employed. Molecular interactions of chemical compounds from the essential oil with the GABA_A receptor was explored via molecular docking experiments. Using behavioral tests, we demonstrated that inhalation of S. multicaulis essential oil exerts significant antiamnesic activity as well as anxiolytic-antidepressant-like effects in the Sco-treated rats. Our data revealed that S. multicaulis oil could act as a promising phytopharmaceutical agent for improving dementia-related abnormalities.

Cognitive-enhancing and antioxidant activities of the aqueous extract from Markhamia tomentosa (Benth.) K. Schum. stem bark in a rat model of scopolamine

BACKGROUND

Plants of the genus Markhamia have been traditionally used by different tribes in various parts of West African countries, including Cameroun. Markhamia tomentosa (Benth.) K. Schum. (Bignoniaceae) is used as an antimalarial, anti-inflammatory, analgesic, antioxidant and anti-Alzheimer agent. The current study was undertaken in order to investigate its anti-amnesic and antioxidant potential on scopolamine-induced cognitive impairment and to determine its possible mechanism of action.

METHODS

Rats were pretreated with the aqueous extract (50 and 200 mg/kg, p.o.), for 10 days, and received a single injection of scopolamine (0.7 mg/kg, i.p.) before training in Y-maze and radial arm-maze tests. The biochemical parameters in the rat hippocampus were also assessed to explore oxidative status. Statistical analyses were performed using two-way ANOVA followed by Tukey's post hoc test. F values for which p < 0.05 were regarded as statistically significant.

RESULTS

In the scopolamine-treated rats, the aqueous extract improved memory in behavioral tests and decreased the oxidative stress in the rat hippocampus. Also, the aqueous extract exhibited anti-acetylcholinesterase activity.

CONCLUSIONS

These results suggest that the aqueous extract ameliorates scopolamine-induced spatial memory impairment by attenuation of the oxidative stress in the rat hippocampus.