Antidepressant effects of the water extract from Taraxacum officinale leaves and roots in mice

Dandelion (Taraxacum Genus): A Review of Chemical Constituents and Pharmacological Effects

Dandelion (Taraxacum genus) is a perennial herb belonging to the Asteraceae family. As a well-known and extensively studied genus, dandelion comprises numerous species. Some species have been widely used in both complementary and alternative medicine to clear heat, detoxify, activate blood circulation, dispel stasis, and discharge urine. Multiple pharmacological studies have highlighted its therapeutic potential, including anti-bacterial, anti-oxidant, anti-cancer, and anti-rheumatic activities. Furthermore, bioactive compounds associated with these effects include sesquiterpenoids, phenolic compounds, essential oils, saccharides, flavonoids, sphingolipids, triterpenoids, sterols, coumarins, etc. Based on recent studies about the Taraxacum genus, the present review critically evaluates the current state of dandelion utilization and summarizes the significant roles of dandelion and its constituents in different diseases. We also focus on the reported phytology, chemical composition, pharmacology, and toxicity of dandelion, along with the main possible action mechanisms behind their therapeutic activities. Meanwhile, the challenges and future directions of the Taraxacum genus are also prospected in this review, thus highlighting its pharmaceutical research and practical clinical applications.

Phenolic Acids as Antidepressant Agents

Depression is a psychiatric disorder affecting the lives of patients and their families worldwide. It is an important pathophysiology; however, the molecular pathways involved are not well understood. Pharmacological treatment may promote side effects or be ineffective. Consequently, efforts have been made to understand the molecular pathways in depressive patients and prevent their symptoms. In this context, animal models have suggested phytochemicals from medicinal plants, especially phenolic acids, as alternative treatments. These bioactive molecules are known for their antioxidant and antiinflammatory activities. They occur in some fruits, vegetables, and herbal plants. This review focused on phenolic acids and extracts from medicinal plants and their effects on depressive symptoms, as well as the molecular interactions and pathways implicated in these effects. Results from preclinical trials indicate the potential of phenolic acids to reduce depressive-like behaviour by regulating factors associated with oxidative stress, neuroinflammation, autophagy, and deregulation of the hypothalamic-pituitary-adrenal axis, stimulating monoaminergic neurotransmission and neurogenesis, and modulating intestinal microbiota.

Antihypernociceptive and Neuroprotective Effects of the Aqueous and Methanol Stem-Bark Extracts of Nauclea pobeguinii (Rubiaceae) on STZ-Induced Diabetic Neuropathic Pain

The greatest common and devastating complication of diabetes is painful neuropathy that can cause hyperalgesia and allodynia. It can disturb psychosocial functioning by increasing levels of anxiety and depression. This work was designed to evaluate the antihyperalgesic, antidepressant, and anxiolytic-like effects of the aqueous and methanol extracts of Nauclea pobeguinii stem-bark in diabetic neuropathy induced by streptozotocin in mice. Diabetic neuropathy was induced in mice by the intraperitoneal administration of 200 mg/kg streptozotocin (STZ) to provoke hyperglycemia. Nauclea pobeguinii aqueous and methanol extracts at the doses of 150 and 300 mg/kg were administered by oral route, and their effects were evaluated on antihyperalgesic activity (Von Frey filaments, hot plate, acetone, and formalin tests), blood glucose levels, body weight, serum, sciatic nerve proinflammatory cytokines (TNF-α, IL-1β, and IL-6) and sciatic nerve growth factor (IGF and NGF) rates, depression (open field test, forced swimming test, tail suspension test), and anxiety (elevated plus maze, light-dark box test, social interaction). Oral administration of Nauclea pobeguinii stem-bark aqueous and methanol extracts (150 and 300 mg/kg) produced antihyperalgesic, antidepressant, and anxiolytic-like effects in STZ-induced diabetic neuropathic mice. Extracts also triggered a decrease in glycaemia and increased body weight in treated animals. They also significantly (p <0.001) reduced tumour necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), and IL-6 and significantly (p <0.001) increased nerve growth factor (NGF) and insulin-like growth factor (IGF) in sciatic nerves. The results of this study confirmed that Nauclea pobeguinii aqueous and methanol extracts possess antihyperalgesic, antidepressant, and anxiolytic activities and could be beneficial therapeutic agents.

Antihypernociceptive, Anxiolytic, and Antidepressant Properties of Aqueous and Ethanol Extracts of Dissotis thollonii Cogn. (Melastomataceae) in Mice

Diabetic neuropathy, which affects 7 to 9% of the world's population and that is usually accompanied by anxiety and depression, is chronic pain that results from impaired function of the central or peripheral nervous system. This study aimed at evaluating the antihypernociceptive, antiallodynic, anxiolytic, and antidepressant effects of Dissotis thollonii extracts. Diabetic neuropathy was induced by intraperitoneal injection of streptozotocin (200 mg/kg) in mice. The aqueous and ethanol extracts (250 and 500 mg/kg) were administered orally. Hyperalgesia (thermal and chemical), allodynia (mechanical and thermal), anxiety (high plus labyrinth, light-dark box, and social interaction), and depression (open field test, suspension test tail, and forced swimming test) were evaluated, and then the levels of some cytokines and growth factors were determined. The aqueous and ethanol extracts of Dissotis thollonii demonstrated significant antihypernociceptive (inhibition of hyperalgesia and allodynia), anxiolytic, and antidepressant activities in mice made diabetic by STZ. The extracts also significantly inhibited (p < 0.001) the levels of TNF-α, IL-1β, and IL-6 in the blood as well as the levels of TNF-α, IL-1β, IL-6, IGF, and NGF in the sciatic nerve. This study shows that the extracts of Dissotis thollonii have antihypernociceptive and neuroprotective effects which could be linked to the inhibition of proinflammatory cytokines and growth factors in the blood and the sciatic nerve.

Reversal of heavy metal-induced antibiotic resistance by dandelion root extracts and taraxasterol

Introduction. Metal exposure is an important factor for inducing antibiotic resistance in bacteria. Dandelion extracts have been used for centuries in traditional Chinese and Native American medicine.

Aim. We assessed the effects of dandelion water extracts and taraxasterol on heavy metal-induced antibiotic resistance in Escherichia coli as well as the underlying mechanisms.

Methodology. Dandelion extracts were obtained through 4 h of boiling in distilled water. Bacterial growth was monitored with a spectrophotometer. Biochemical assays were performed to assess the activities and gene transcriptions of β-lactamase and acetyltransferase. Oxidative stress was determined using an oxidation-sensitive probe, H2DCFDA.

Results. The present study demonstrated that higher concentrations of nickel (>5 µg ml−1), cadmium (>0.1 µg ml−1), arsenic (>0.1 µg ml−1) and copper (>5 µg ml−1) significantly inhibited the growth of E. coli . Lower concentrations of nickel (0.5 µg ml−1), cadmium (0.05 µg ml−1) and arsenic (0.05 µg ml−1) had no effect on bacterial growth, but helped the bacteria become resistant to two antibiotics, kanamycin and ampicillin. The addition of dandelion root extracts and taraxasterol significantly reversed the antibiotic resistance induced by these heavy metals. The supplements of antibiotics and cadmium generated synergistic effects on the activities of β-lactamase and acetyltransferase (two antibiotic resistance-related proteins), which were significantly blocked by either dandelion root extract or taraxasterol. In contrast, oxidative stress was not involved in the preventative roles of dandelion root extracts and taraxasterol in heavy metal-induced antibiotic resistance.

Conclusion. This study suggests that heavy metals induce bacterial antibiotic resistance and dandelion root extracts and taraxasterol could be used to help reverse bacterial resistance to antibiotics.

Acaricidal efficacy of Calotropis procera (Asclepiadaceae) and Taraxacum officinale (Asteraceae) against Rhipicephalus microplus from Mardan, Pakistan

Medicinal plants are used by traditional folk healers, modern physicians, and veterinarians as an alternative to conventional drugs to treat a wide range of disorders including parasitic diseases. Some compounds from these plants have been shown to have acaricidal activity and repel arthropods. The cattle tick Rhipicephalus microplus is one of the most destructive pests to the livestock industry in tropical and subtropical parts of the world. The potential to develop herbal acaricides to control R. microplus infestations is critical in maintaining cattle herd productivity, reducing economic losses, and curtailing the overuse of synthetic chemical acaricides. Calotropis procera, the apple of Sodom, and Taraxacum officinale, the common dandelion, were evaluated for acaricidal activity against R. microplus larvae and adults in vitro. Both plant species tested are common indigenous species of Pakistan where R. microplus infestations are widespread across livestock species including cattle, sheep, and goats. Whole-plant extracts derived from C. procera and T. officinale significantly reduced the index of egg laying (P < 0.01) and increased the percent inhibition of oviposition of adult female ticks at a concentration of 40 mg/mL when assessed by the adult immersion test (AIT). Calotropis procera and T. officinale treatments at the same concentration also resulted in larval mortality of 96.0% ± 0.57 and 96.7% ± 0.88, respectively, as measured using the larval packet test (LPT). An increasing range of extract concentrations was tested to determine the LD₅₀ and LD₉₀ for C. procera, 3.21 and 21.15 mg/mL, respectively, and T. officinale, 4.04 and 18.92 mg/mL, respectively. These results indicate that further studies are warranted to determine the relative contribution of individual phytochemicals from whole-plant extracts on acaricidal activity. This information will guide the design of further acaricidal efficacy tests using livestock infested with R. microplus.

Antidepressive Effects of Taraxacum Officinale in a Mouse Model of Depression Are Due to Inhibition of Corticosterone Levels and Modulation of Mitogen-Activated Protein Kinase Phosphatase-1 (Mkp-1) and Brain-Derived Neurotrophic Factor (Bdnf) Expression

BACKGROUND Depression is a common disorder linked with high levels of chronicity, psycho-social and physical problems, and suicide. Here, we assessed the antidepressant effects of the hydromethanolic extract of Taraxacum officinale and investigated the underlying mechanism. MATERIAL AND METHODS Antidepressant effects were examined by use of the tail suspension test (TST). Concentrations of corticosterone, dopamine, noradrenaline, and adrenaline were examined by biochemical assays. The mRNA expression was assessed by quantitative RT-PCR. Phytochemical analysis was performed by LC/MS. RESULTS The results showed that the extract at the dosage of 50 and 100 mg/kg significantly (p<0.01) alleviated the TST-induced immobility in the mice, and the effects were comparable to the antidepressant drug Bupropion, which was used as the positive control. Investigation of the underlying mechanism revealed that the T. officinale extract exerts it effects by significantly (p<0.05) decreasing the levels of corticosterone and increasing the concentrations of dopamine, noradrenaline, and adrenaline. Further, the extract also increased the expression of brain-derived neurotrophic factor (Bdnf), which was associated with significant (p<0.05) decrease in the expression of mitogen-activated protein kinase phosphatase-1 (Mkp-1), indicative of the antidepressant potential of T. officinale. Finally, the active constituents of the extract, which include isoetin, hesperidin, naringenin, Kaempferol, sinapinic, and gallic acid, were also identified, which could potentially be responsible for its antidepressant effects. CONCLUSIONS In conclusion, T. officinale exerts significant antidepressant effects in a mouse model of depression by inhibition of corticosterone levels and modulation of Mkp-1 and Bdnf expression.

Neuroprotective Effects of Taraxacum officinale Wigg. Extract on Glutamate-Induced Oxidative Stress in HT22 Cells via HO-1/Nrf2 Pathways

Oxidative stress-mediated neuron damage is considered an important contributor to the pathogenesis and development of neurodegenerative diseases. Taraxacum officinale has been reported to possess antioxidant activities. However, whether it can protect neurons against oxidative damage and the underlying molecular mechanisms have not been fully determined. In the present study, we examined the neuroprotective effects of ethanol extracts of this plant (ETOW) on glutamate-induced oxidative stress in HT22 cells. Both cell viability and reactive oxygen species (ROS) assays showed that ETOW effectively attenuated glutamate-induced cytotoxicity and ROS generation. Furthermore, our results revealed that ETOW increased the expression of heme oxygenase-1 (HO-1) and promoted the nuclear translocation of nuclear factor erythroid 2-related factor-2 (Nrf2). The inhibitory effects of ETOW on glutamate-stimulated cell toxicity and ROS production were partially reversed by tin protoporphyrin (SnPP), an HO activity inhibitor. Taken together, these results demonstrate that ETOW can protect HT22 cells against glutamate-induced oxidative damage by inducing the Nrf2/HO-1 pathways. Our study supports the idea that Taraxacum officinale Wigg. is a promising agent for preventing neurodegenerative diseases.

The use of medicinal herbs in gynecological and pregnancy-related disorders by Jordanian women: a review of folkloric practice vs. evidence-based pharmacology

Context National statistical reports in Jordan indicate a decrease in the total fertility rate along with a parallel increase in contraceptive use. The folkloric use of medicinal herbs in gynecological disorders has been growing in Jordan, despite of deficient reports on the evidence-based safety and efficacy of these practices. Objective The aim of this comprehensive article is to review medicinal plants with claimed ethnonpharmacological usage in various gynecological and pregnancy-related issues in Jordan, and to assess their evidence-based pharmacological studies as well as their phytochemistry. Methods The published literature was surveyed using Google Scholar entering the terms "ethnopharmacology AND Jordan AND infertility AND gynecology OR gestation". We included ethnopharmacological surveys in Jordan with available full-text. Results Twelve articles were reviewed. Plant species which are commonly used for female gynecological issues such as Artemisia monosperma Del. and A. herba-alba Asso. (Asteraceae) have been found to exert an antifertility effect. Ricinus communis L. (Euphorbiaceae) and Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) had antifertility effects in male rats, but Nigella sativa oil L. (Ranunculaceae) and Cinnamon zeylanicum J. Presl (Lauraceae) were found to enhance it. Conclusion Using plants for gynecological disorders is a common practice in Jordan. Many of them, whether utilised for gynecological or non-gynecological conditions equally, were found to have detrimental effects on female or male fertility. Thus, couples planning pregnancy should be discouraged from the consumption of these herbs. Further local studies are warranted to confirm the appreciable beneficial pharmacological effects and safety of these plants.