Neuroprotection by extract of Petasites japonicus leaves, a traditional vegetable, against oxidative stress in brain of mice challenged with kainic acid

Petasites japonicus extract exerts anti-malarial effects by inhibiting platelet activation

BACKGROUND

New antimalarial agents are needed to combat emerging resistance to the currently available drugs. In the pathology of cerebral malaria, platelets play a central role by binding infected and uninfected red cells and the endothelium. Since Petasites japonicus extract was reported as an effective inhibitor of platelet activation, we examined the antimalarial activities of the P. japonicus extract.

PURPOSE

This study aimed to evaluate the impact of P. japonicus extract prepared from whole plants on malarial infection.

METHODS

The P. japonicus extract were characterized by high-performance liquid chromatography (HPLC) profiling. Antimalarial activity of the P. japonicus ethanolic extract was evaluated in vitro using chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) P. berghei strains. Also, the in vivo activity of the extract was evaluated in P. berghei-infected mice via oral administration followed by a four-day suppressive test to measure the hematological parameters. In addition, platelet activation signaling induced by the P. japonicus extract in P. berghei infection was evaluated.

RESULTS

In HPLC study, catechin, rutin, liquiritin, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid were identified in P. japonicus extract. Exposure to the P. japonicus extract significantly inhibited both CQ-sensitive (3D7) and resistant (Dd2) strains of P. falciparum with IC₅₀ values of 8.48 ± 1.70 and 7.83 ± 6.44 μg/ml, respectively. Administration of the P. japonicus extract also resulted in potent antimalarial activities in P. berghei-infected mice with no associated toxicity. The treatment also improved the hematologic parameters. In addition, the survived mice from P. berghei infection exhibited the inhibition of collagen-induced platelet aggregation by attenuated glycoprotein VI (GPVI) downstream signaling.

CONCLUSION

P. japonicus extracts promote antimalarial effects both in vitro and in vivo. In addition, the effects appear to be induced by the inhibition of collagen-induced platelet activation related to attenuated GPVI downstream signaling. Further studies to identify and characterize the antimalarial compounds in P. japonicus will promote the development of new drugs.

A review on the ethnobotany, phytochemistry, pharmacology and toxicology of butterbur species (Petasites L.)

ETHNOPHARMACOLOGICAL RELEVANCE

Petasites (butterbur, Asteraceae) species have been used since Ancient times in the traditional medicine of Asian and European countries to treat central nervous system (migraine), respiratory (asthma, allergic rhinitis, bronchitis, spastic cough), cardiovascular (hypertension), gastrointestinal (ulcers) and genitourinary (dysmenorrhea) disorders.

AIM OF THE REVIEW

This study summarized and discussed the traditional uses, phytochemical, pharmacological and toxicological aspects of Petasites genus.

MATERIALS AND METHODS

A systematic search of Petasites in online databases (Scopus, PubMed, ScienceDirect, Google Scholar) was performed, with the aim to find the phytochemical, toxicological and bioactivity studies. The Global Biodiversity Information Facility, Plants of the World Online, World Flora Online and The Plant List databases were used to describe the taxonomy and geographical distribution.

RESULTS

The detailed phytochemistry of the potentially active compounds of Petasites genus (e.g. sesquiterpenes, pyrrolizidine alkaloids, polyphenols and essential oils components) was presented. The bioactivity studies (cell-free, cell-based, animal, and clinical) including the traditional uses of Petasites (e.g. anti-spasmolytic, hypotensive, anti-asthmatic activities) were addressed and followed by discussion of the main pharmacokinetical and toxicological issues related to the administration of butterbur-based formulations.

CONCLUSIONS

This review provides a complete overview of the Petasites geographical distribution, traditional use, phytochemistry, bioactivity, and toxicity. More than 200 different sesquiterpenes (eremophilanes, furanoeremophilanes, bakkenolides), 50 phenolic compounds (phenolic acids, flavonoids, lignans) and volatile compounds (monoterpenes, sesquiterpenes) have been reported within the genus. Considering the phytochemical complexity and the polypharmacological potential, there is a growing research interest to extend the current therapeutical applications of Petasites preparations (anti-migraine, anti-allergic) to other human ailments, such as central nervous system, cardiovascular, malignant or microbial diseases. This research pathway is extremely important, especially in the recent context of the pandemic situation, when there is an imperious need for novel drug candidates.

Single and Repeated Oral Dose Toxicity and Genotoxicity of the Leaves of Butterbur

Butterbur (Petasites japonicus (Siebold & Zucc.) Maxim) leaves are available to consumers in the marketplace, but there is no guarantee that they are safe for human consumption. Previously, we demonstrated that hot water extracts of P. japonicus leaves (KP-1) had anti-inflammatory properties and attenuated memory impairment. However, data regarding KP-1 toxicity are lacking. This study assessed the safety of KP-1 by examining oral and genotoxic effects using in vivo and in vitro tests, respectively. In a single oral dose toxicity and two-week repeated oral dose toxicity study, we observed no toxicologically significant clinical signs or changes in hematology, blood chemistry, and organ weights at any dose during the experiment. Following a thirteen-week repeated oral dose, toxicity, hyperkeratosis, and squamous cell hyperplasia of the limiting ridge in the stomach were observed. The no observable adverse effect level (NOAEL) was found to be 1250 mg/kg/day in male and female rats. However, hyperkeratosis and hyperplasia were not considered to be of toxicological significance when extrapolating the NOAEL to humans because the limiting ridge in the stomach is species-specific to rats. Therefore, in our study, the NOAEL was considered to be 5000 mg/kg/day when the changes in the stomach’s limiting ridge were discounted. Moreover, in vitro bacterial reverse mutations and chromosomal aberrations in Chinese hamster lung (CHL) cells and the in vivo micronucleus in Institute of cancer research (ICR) mice assays showed that KP-1 possessed no mutagenicity. Although additional research is required, these toxicological evaluations suggest that KP-1 could be safe for human consumption.

Sesquiterpene-Loaded Co-Polymer Hybrid Nanoparticle Effects on Human Mast Cell Surface Receptor Expression, Granule Contents, and Degranulation

Biodegradable polymeric nanoparticles (NPs) such as poly(lactic-co-glycolic acid) (PLGA) and polyvinyl alcohol (PVA) have been used as drug delivery systems for natural and synthetic compounds and are designed to control the loading and release of biodegradable materials to target cells, tissues, and organs. Eremophilane-type sesquiterpenes have anti-inflammatory properties but are lipophilic, cytotoxic, and not biocompatible with many cells. To determine whether biodegradable PLGA/PVA could improve the biocompatibility of sesquiterpenes, sesquiterpene-loaded NPs were synthesized and their effects on human mast cells (LAD2), the major effector cells of allergic inflammation, were determined. NPs composed of PLGA/PVA and two types of sesquiterpenes (fukinone, PLGA/PVA-21 and 10βH-8α,12-epidioxyeremophil-7(11)-en-8β-ol, PLGA/PVA-22) were produced using a microfluidic synthesis method. The NPs’ size distribution and morphology were evaluated by dynamic light scattering and cryogenic transmission electron microscopy (TEM). PLGA/PVA-21 and PLGA/PVA-22 were 60 to 70 nm and were readily internalized by LAD2 as shown by flow cytometry, fluorescence microscopy, and TEM. While unencapsulated sesquiterpenes decreased LAD2 cell viability by 20%, PLGA/PVA-21 and PLGA/PVA-22 did not alter LAD2 viability, showing that encapsulation improved the biocompatibility of the sesquiterpenes. PLGA/PVA-21 and PLGA/PVA-22 decreased the expression of genes encoding the subunits of the high affinity immunoglobulin E receptor (FcεR1α, FcεR1β, FcεR1γ) and the stem cell factor receptor (Kit,), suggesting that hybrid NPs could alter mast cell responses to antigens and shift their maturation. Similarly, PLGA/PVA-21 and PLGA/PVA-22 inhibited tryptase expression but had no effect on chymase expression, thereby promoting a shift to the tryptase-positive phenotype (MC_T). Lastly, PLGA/PVA-21 and PLGA/PVA-22 inhibited mast cell degranulation when the LAD2 cells were activated by IgE crosslinking and FcεRI. Overall, our results suggest that PLGA/PVA-21 and PLGA/PVA-22 alter human mast cell phenotype and activation without modifying viability, making them a more biocompatible approach than treating cells with sesquiterpenes alone.

Effect of thiamazole on kainic acid-induced seizures in mice

Kainic acid (KA) induced epileptic seizures in mice is a commonly used experimental model of epilepsy. Previous studies have suggested the roles of various neurotransmitters and oxidative stress in KA-induced seizures. An important role of hypothyroidism has also been suggested in epilepsy. Thiamazole (TZ) is an anti-hyperthyroid drug with antioxidant property. This study reports the effect of TZ on KA-induced epileptic seizures in mice, produced by intraperitoneal (IP) injection of KA (18 mg/kg). Prior to KA injection, the animals were treated with TZ (12.5, 25 and 50 mg/kg IP). Our results showed that in KA alone group, about half of the animals developed seizures. Pre-treatment of mice with TZ significantly increased the frequency of seizures in dose-dependent manner. Administration of TZ significantly reduced the latency time and aggravated the severity of seizures. TZ also increased the mortality in KA-treated mice. Striatal dopamine and serotonin levels were markedly increased in KA alone treated mice, which were not significantly affected by TZ treatment. Among the indices of oxidative stress, we observed a significant reduction in cerebral vitamin E whereas the levels of cerebral malondialdehyde and conjugated dienes were significantly increased in animals with high severity of seizures. In conclusion, TZ potentiated the frequency and severity of experimental seizure in mice. There is a possibility of altered metabolism of KA in presence of TZ that might have potentiated the toxicity of KA. These findings suggest a caution while administering anti-hyperthyroid drugs in epileptic seizures.

S-petasin induces apoptosis and inhibits cell migration through activation of p53 pathway signaling in melanoma B16F10 cells and A375 cells

Melanoma is a dangerous type of skin cancer that develops from the melanocytes. Activation of p53 in melanoma cells has been validated as a strategy for melanoma therapy. S-Petasin, a dietary sesquiterpene isolated from Petasites japonicus, has been shown to possess multiple biological effects. However, no studies have reported that s-petasin exerted anti-melanoma or inhibited activity in melanoma cells. We investigated the effect of s-petasin in B16F10 cells and A375 cells and the underlying molecular mechanism. S-Petasin exerted a significant anti-proliferation effect on B16F10 cells and A375 cells as measured by the MTT assay and crystal violet staining assay. S-Petasin induced cell apoptosis in B16F10 cells and A375 cells as evidenced by flow cytometry assay and western blot assay. Wound healing assay and transwell cell migration and invasion assay revealed that s-petasin suppressed B16F10 cells and A375 cells migration in vitro. For mechanism study, western blot assay indicated that s-petasin activated the p53 pathway signaling. Furthermore, expression of Bcl-2, Bcl-_XL, Bax, MMP-2, MMP-9, p21, CDK4 and cyclin D₁ were regulated by s-petasin. Taken together, our data suggest that s-petasin is a novel compound which can induce apoptosis and inhibit cell migration through activation of the p53 pathway signaling in melanoma B16F10 cells and A375 cells.

Antioxidant compounds of Petasites japonicus and their preventive effects in chronic diseases: a review

Petasites japonicus (P. japonicus) is a plant of the Asteraceae family. Its roots and stems have been used for the treatment or the prophylaxis of migraine and tension headache as a traditional Chinese medicine in Japan and Korea. Sesquiterpenoids, lignans, and flavonoids are components of P. japonicus. Regarding the biological activity of P. japonicus, its anti-allergic effect has been researched extensively using IgE antigen-stimulated degranulation of RBL-2H3 cells or passive cutaneous anaphylaxis reaction in experimental animal models. The study of the antioxidant activity of P. japonicus was initiated approximately 15 years ago using in vitro assays. In addition, its in vivo effect has also been examined in animal models with induced oxidative injury. Moreover, recently, many types of antioxidant compounds have been rapidly and simultaneously identified using the liquid chromatography–mass spectrometry technique. The number of reports on the other functions of this plant, such as its neuroprotective and anti-inflammatory effects, has been increasing. In this review, I summarized the studies of functional foods derived from P. japonicus, which may provide a basis for the development of potential functional foods. Finally, I discuss the future research avenues in this field.

Anti-Obesity Effects of Petasites japonicus (Meowi) Ethanol Extract on RAW 264.7 Macrophages and 3T3-L1 Adipocytes and Its Characterization of Polyphenolic Compounds

Koreans have been consuming Petasites Japonicus (PJ) as food. Although the therapeutic effect of PJ on allergic or inflammatory reactions associated with asthma has been proven, its effect on obesity is unclear. Therefore, the present study was aimed to assess the obesity related anti-inflammatory and anti-adipogenic effects of ethanol extract PJ (EPJ) on the inflammatory response in RAW 264.7 macrophages and on differentiation in 3T3-L1 adipocytes. In addition, the polyphenolic compound was quantitatively characterized from the EPJ using ultra performance liquid chromatography coupled with diode array detector, quadrupole time-of-flight-mass spectrometry (UPLC-DAD-QToF-MS). In RAW 264.7 or 3T3-L1, reduction of nitric oxide (in macrophages) production as well as monocyte chemoattractant protein-1 and tumor necrosis factor-α were observed. Treatment of EPJ in adipocyte differentiation showed an improvement in adiponectin and lipid accumulation and a significant reduction of PPARγ and FABP-4 mRNA expression levels. On the other hand, mRNA expression of UCP-1, PPARα, and ACO increased in the EPJ treated group. In addition, a total of 26 polyphenolic compounds were detected and of which 12 are reported for the first time from PJ. The higher content of diverse polyphenolic compounds presented in EPJ might be responsible for the observed anti-inflammatory and anti-adipogenic effect. These results suggest that PJ is valuable in improving obesity-related inflammatory responses.

S-petasin inhibits lipid accumulation in oleic acid-induced HepG2 cells through activation of the AMPK signaling pathway

S-petasin inhibits lipid accumulation in oleic acid-induced HepG2 cells.

S-Petasin isolated from Petasites japonicus exerts anti-adipogenic activity in the 3T3-L1 cell line by inhibiting PPAR-γ pathway signaling

S-Petasin from Petasites japonicus exerts anti-adipogenic activity in 3T3-L1 cells through inhibition of the expression of PPAR-γ.

Neuroprotective Strategies for Neurological Disorders by Natural Products: An update

Nature has bestowed mankind with surplus resources (natural products) on land and water. Natural products have a significant role in the prevention of disease and boosting of health in humans and animals. These natural products have been experimentally documented to possess various biological properties such as antioxidant, anti-inflammatory and anti-apoptotic activities. In vitro and in vivo studies have further established the usefulness of natural products in various preclinical models of neurodegenerative disorders. Natural products include phytoconstituents, like polyphenolic antioxidants, found in herbs, fruits, nuts, vegetables and also in marine and freshwater flora. These phytoconstituents may potentially suppress neurodegeneration and improve memory as well as cognitive functions of the brain. Also, they are known to play a pivotal role in the prevention and cure of different neurodegenerative diseases, such as Alzheimer's disease, epilepsy, Parkinson's disease and other neuronal disorders. The large-scale neuro-pharmacological activities of natural products have been documented due to the result of either the inhibition of inflammatory processes, or the up-regulation of various cell survival proteins or a combination of both. Due to the scarcity of human studies on neuroprotective effects of natural products, this review focuses on the various established activities of natural products in in vitro and in vivo preclinical models, and their potential neuro-therapeutic applications using the available knowledge in the literature.

Bicyclic eremophilane-type petasite sesquiterpenes potentiate peroxisome proliferator-activated receptor γ activator-mediated inhibition of dendritic cells

Dendritic cell (DC) activation induces expression of co-stimulatory surface molecules, as well as migration into secondary lymphoid organs, where they activate naïve T-cells. A family of plant derivatives, eremophilane-type petasite sesquiterpenes, can regulate the immune system through DC targeting due to their anti-inflammatory effects. Peroxisome proliferator–activated receptor gamma (PPARγ) is involved in inhibition of inflammatory responses and induction of DCs to acquire a mucosal phenotype. Since mucosal DCs are central in innate immune responses, we hypothesized that eremophilane-type petasite sesquiterpenes exerted their anti-inflammatory effects by inhibiting DC maturation and activation through PPARγ. This study assessed the bicyclic eremophilane-type petasite sesquiterpene compounds Fukinone and 10βH-8α,12-Epidioxyeremophil-7(11)-en-8β-ol (ZYFDC21 and ZYFDC22) in the maturation and activation of mouse DC. We measured surface expression of co-stimulatory molecules by flow cytometry and cell-free supernatant cytokine production upon lipopolysaccharide stimulation by enzyme-linked immunosorbent assays (ELISAs) in the presence or absence of PPARγ agonists. DCs were generated from C57BL/6 mice bone marrow cells and harvested. Cells were exposed to bicyclic eremophilane-type petasite sesquiterpenes ZYFDC21 or ZYFDC22 in the presence or absence of synthetic PPARγ agonists (GW1929 and TGZ) or the natural PPARγ ligand 15d-PGJ₂, followed by overnight activation with LPS. We observed differences in the upregulation of surface expression of CD86, along with TNF, IL-6, and IL-12p70 released by DCs stimulated with LPS, when using combinations of bicyclic eremophilane-type petasite sesquiterpenes ZYFDC21 or ZYFDC22, and PPARγ agonists, in particular the PPARγ ligand 15d-PGJ₂. Our results indicate that bicyclic eremophilane-type petasite sesquiterpenes ZYFDC21 or ZYFDC22 inhibit maturation and activation of DC, and this activity is augmented upon PPARγ activation.

LC-MS/MS characterization, anti-inflammatory effects and antioxidant activities of polyphenols from different tissues of Korean Petasites japonicus (Meowi)

The Korean Petasites japonicus is a perennial plant used in folk medicine as a remedy for many diseases and popularly consumed as spring greens. Ten polyphenols were characterized from the leaves, stems and roots of this plant via high-performance liquid chromatography-tandem mass spectrometry. Individual polyphenols were quantified for the first time using calibration curves of six structurally related external standards. Validation data indicated that coefficients of determinations (R² ) were ≥0.9702 for all standards. Recoveries measured at 50 and 100 mg/L were 80.0-91.9 and 80.3-105.3%, respectively. Precisions at these two concentration levels were 0.7-6.1 and 1.1-5.5%, respectively. The total number of identified components was largest for the leaves and smallest for the stems. The leaf and root polyphenolic extracts showed anti-inflammatory effects by inducing LPS-activated COX-2 and iNOS protein levels in mouse macrophage RAW 264.7 cells. The antioxidant capacity of the polyphenols, when evaluated for DPPH (α,α-diphenyl-β-picrylhydrazyl)^ˑ , ABTS⁺ [2-2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] and superoxide radical scavenging activities, and in ferric reducing ability of plasma (FRAP) assays, was highest in the leaf and lowest in the stem. This trend suggests that the antioxidant capacities depend primarily on polyphenol concentration in each tissue. The current findings suggest that polyphenols derived from P. japonicas tissues could have potential as functional health foods.

Kainic Acid-Induced Excitotoxicity Experimental Model: Protective Merits of Natural Products and Plant Extracts

Excitotoxicity is well recognized as a major pathological process of neuronal death in neurodegenerative diseases involving the central nervous system (CNS). In the animal models of neurodegeneration, excitotoxicity is commonly induced experimentally by chemical convulsants, particularly kainic acid (KA). KA-induced excitotoxicity in rodent models has been shown to result in seizures, behavioral changes, oxidative stress, glial activation, inflammatory mediator production, endoplasmic reticulum stress, mitochondrial dysfunction, and selective neurodegeneration in the brain upon KA administration. Recently, there is an emerging trend to search for natural sources to combat against excitotoxicity-associated neurodegenerative diseases. Natural products and plant extracts had attracted a considerable amount of attention because of their reported beneficial effects on the CNS, particularly their neuroprotective effect against excitotoxicity. They provide significant reduction and/or protection against the development and progression of acute and chronic neurodegeneration. This indicates that natural products and plants extracts may be useful in protecting against excitotoxicity-associated neurodegeneration. Thus, targeting of multiple pathways simultaneously may be the strategy to maximize the neuroprotection effect. This review summarizes the mechanisms involved in KA-induced excitotoxicity and attempts to collate the various researches related to the protective effect of natural products and plant extracts in the KA model of neurodegeneration.

N-palmitoyl serotonin alleviates scopolamine-induced memory impairment via regulation of cholinergic and antioxidant systems, and expression of BDNF and p-CREB in mice

N-Palmitoyl-5-hydroxytryptamines (Pal-5HT), a cannabinoid, has recently been reported to express anti-allergic and anti-inflammatory actions in RBL-2H3 cells, and ameliorate glutamate-induced cytotoxicity in HT-22 cells. In this study, we examined the effect of Pal-5HT on deficits of learning and memory induced by scopolamine in mice. Memory performance was evaluated using Morris water maze test and passive avoidance test. Activities of acetylcholinesterase (AChE) and choline acetyltransferase (ChAT), level of oxidative stress markers, and expression of brain-derived neurotrophic factor (BDNF), phosphorylation of cAMP response element-binding protein (p-CREB) were determined. Loss of neuronal cells in hippocampus was evaluated by histological examinations. Pal-5HT significantly improved the amnesia in the behavioral assessment. Pal-5HT regulated cholinergic function by inhibiting scopolamine-induced elevation of AChE activity and decline of ChAT activity. Pal-5HT suppressed oxidative stress by increasing activities of glutathione peroxidase (GPx), glutathione reductase (GR) or NAD(P)H quinine oxidoreductase-1 (NQO-1) and lowering MDA level. Additionally, it prevented against scopolamine-induced expression of iNOS and COX-2. Moreover, Pal-5HT suppressed the death of neuronal cells in CA1 and CA3 regions, while it restored expression of p-CREB and BDNF in hippocampus. Taken together, Pal-5HT is suggested to ameliorate deficits of memory and learning through regulation of cholinergic function, activation of antioxidant systems as well as restoration of BDNF and p-CREB expression. From these, Pal-5HT may be a potential candidate to prevent against neurodegeneration related to the memory deficit.

Deer bone extract prevents against scopolamine-induced memory impairment in mice

Deer bone has been used as a health-enhancing food as well as an antiaging agent in traditional Oriental medicine. Recently, the water extract of deer bone (DBE) showed a neuroprotective action against glutamate or Aβ1-42-induced cell death of mouse hippocampal cells by exerting antioxidant activity through the suppression of MAP kinases. The present study is to examine whether DBE improves memory impairment induced by scopolamine. DBE (50, 100 or 200 mg/kg) was administered orally to mice for 14 days, and then scopolamine (2 mg/kg, i.p.) was administered together with DBE for another 7 days. Memory performance was evaluated in the Morris water maze (MWM) test and passive avoidance test. Also, brain acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) activity, biomarkers of oxidative stress and the loss of neuronal cells in the hippocampus, was evaluated by histological examinations. Administration of DBE significantly restored memory impairments induced by scopolamine in the MWM test (escape latency and number of crossing platform area), and in the passive avoidance test. Treatment with DBE inhibited the AChE activity and increased the ChAT activity in the brain of memory-impaired mice induced by scopolamine. Additionally, the administration of DBE significantly prevented the increase of lipid peroxidation and the decrease of glutathione level in the brain of mice treated with scopolamine. Also, the DBE treatment restored the activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, and glutathione reductase to control the level. Furthermore, scopolamine-induced oxidative damage of neurons in hippocampal CA1 and CA3 regions were prevented by DBE treatment. It is suggested that DBE may be useful for memory improvement through the regulation of cholinergic marker enzyme activities and the suppression of oxidative damage of neurons in the brain of mice treated with scopolamine.

Isolation, characterization, and neuroprotective activities of sesquiterpenes from Petasites japonicus

Neuroprotective reagents to protect the nerve cells against oxidative stress and other damages are potentially effective for the medical treatment of Parkinson's disease. Petasites japonicus, a wild vegetable, belongs to the family Compositae and its extract has shown the neuroprotective effects. A further phytochemical investigation of P. japonicus for neuroprotective substances led to the isolation of eight new (1-8) and two known (9 and 10) sesquiterpenes. Their structures were elucidated on the basis of extensive 1D and 2D NMR (HMQC, HMBC, (1)H-(1)H COSY, and NOESY) spectroscopic data analyses, and the structure of 1 was confirmed by X-ray crystallography. The neuroprotective activities of these sesquiterpenes were evaluated against cobalt chloride (CoCl2)-induced neuronal cell death in human dopaminergic SH-SY5Y cells. Five compounds showed a neuroprotective activity.

The medical plant butterbur (Petasites): analytical and physiological (re)view

Butterbur (Petasites) is an ancient plant which has been used for medical and edible purposes with its spasmolytic agents. However, toxic alkaloid content of the plant limits its direct usage. The paper covers the pyrrolizidine alkaloids (PAs) and butterbur themes in detail in order to display the outline of alkaloid-free plant extract production for medical and edible purposes. The toxic PAs and medicinal constituents of the plant are described with emphasis on analytics, physiological effects and published patent data on alkaloid free extract production. The analytics is based on several commonly used analytical methods including liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry and enzyme linked immunoassay analysis of PAs and N-oxides based on published literature data of butterbur. The analyses of major medicinal constituents of butterbur are given and the physiological effects of these compounds have been discussed to attract attention to the importance of alkaloid-free extract production. The concentration distributions of the medicinal constituents and toxic PAs in different parts of the plant and the outcomes of the published patent data provide comprehensive information for proper plant raw-material selection and production of alkaloid-free butterbur extracts. The review is intended to guide researchers interested in medical plant extracts by providing comprehensive data on the medical plant butterbur and its chemical constituents.

Determination of bakkenolide A in rat plasma using liquid chromatography/tandem mass spectrometry and its application to a pharmacokinetic study

A sensitive rapid analytical method was established and validated to determine the bakkenolide A (BA) in rat plasma. This method was further applied to assess the pharmacokinetics of BA in rats receiving a single dose of BA. Liquid chromatography tandem mass spectrometry in multiple reaction monitoring mode was used in the method, and costundide was used as internal standard. A simple protein precipitation based on methanol was employed. The combination of a simple sample cleanup and short chromatographic running time (2.4 min) increased the throughput of the method substantially. The method was validated over the range of 1-1000 ng/mL with a correlation coefficient > 0.99. The lower limit of quantification was 1 ng/mL for BA in plasma. Intra- and inter-day accuracies for BA were 93-112% and 103-104%, respectively, and the inter-day precision was less than 15%. After a single oral dose of 20 mg/kg of BA, the mean peak plasma concentration (C(max) ) of BA was 234.7 ± 161 ng/mL at 0.25 h. The area under the plasma concentration-time curve (AUC(0-24 h) ) was 535.8 ± 223.7 h·ng/mL, and the elimination half-life (T(1/2) ) was 5.0 ± 0.36 h. In case of intravenous administration of BA at a dosage of 2 mg/kg, the area under the plasma concentration-time curve (AUC(0-24 h) ) was 342 ± 98 h⋅ng/mL, and the elimination half-life (T(1/2) ) was 5.8 ± 0.7 h. Based on the results, the oral bioavailability of BA in rats at 20 mg/kg is 15.7%.

Effects of structural analogues of nociceptin(1-13)NH₂ on brain antioxidant status in kainic acid-treated rats

The in vivo effects of nociceptin (N/OFQ(1-13)NH(2) ) and its structural analogues ([Dab(9) ]N/OFQ(1-13)NH(2) , [Dap(9) ]N/OFQ(1-13)NH(2) and [Cav(9) ]N/OFQ(1-13)NH(2) ) on the levels of lipid peroxidation and cell antioxidants (enzyme and non-enzyme) in brain of control and kainic acid (KA)-treated rats were studied. In control animals, [Dab(9) ]N/OFQ(1-13)NH(2) and [Dap(9) ]N/OFQ(1-13)NH(2) , unlike N/OFQ(1-13)NH(2) and [Cav(9) ]N/OFQ(1-13)NH(2) , slightly increased the brain lipid peroxidation; the rest of the parameters were unchanged by all neuropeptides tested. KA (0.25 µg in 0.5 µl, i.c.v) increased the lipid peroxidation (4 and 24 h after KA-injection) and decreased the glutathione level (1 h after KA-administration). One hour after KA-administration, the neuropeptides (2 µg in 0.5 µl, injected 30 min before KA) showed the following effects: a slight decrease in the KA-induced lipid peroxidation by all nociceptin analogues and an enhancement of the KA-decreased GSH level, but by [Cav(9) ]N/OFQ(1-13)NH(2) only. The brain antioxidant enzyme activities were unchanged in all used experimental groups. In addition, the nociceptin analogues, especially [Can(9) ]N/OFQ(1-13)NH(2) , showed a good antioxidant capacity in chemical systems, generating reactive oxygen species. In conclusion, the substitution of lysin (Lys) in N/OFQ(1-13)NH(2) molecule with other amino acids might contribute to changes in its antioxidant properties. Copyright © 2011 John Wiley & Sons, Ltd.

Suppressive effect of Petasites japonicus extract on ovalbumin-induced airway inflammation in an asthmatic mouse model

AIM OF THE STUDY

Asthma is a disease marked by airway inflammation. Petasites japonicus (Pj) is known as an herb for treating asthma, oxidant stress and gastric ulcer in traditional Oriental medicine. In this study, the inhibitory effects of Pj extract on asthmatic responses were examined both in vitro and in vivo.

MATERIALS AND METHODS

The Pj extract was acquired from whole plants of Petasites japonicus using 80% ethanol. Cytotoxicity of the Pj extract on Jurkat cells and THP-1 cells was determined using MTT assay. ELISA was performed to determine the expression levels of cytokines, chemokines, and IgE. BALB/c mice were used for an OVA-induced asthmatic mouse model. Reactive oxygen species (ROS) production was stained with 2',7'-dichlorofluorescein diacetate and measured by fluorescence-activated cell sorting analysis. The effects of the Pj extract on leukocyte infiltration and mucus production were determined using periodic acid-Schiff staining as well as hematoxylin and eosin staining.

RESULTS

The Pj extract inhibits the increased release of interleukin (IL)-2, IL-4, IL-5, IL-13, and TNF-α due to house dust mite in Jurkat cells and blocks IL-6 expression in THP-1 cells without cytotoxicity. In the asthmatic mouse model, the Pj extract inhibits eosinophil infiltration, mucus hypersecretion, and IL-5 level in bronchoalveolar lavage (BAL) fluid, and it has a scavenging effect on ROS production of cells in BAL fluid.

CONCLUSION

The Pj extract has suppressive properties for the pathogenesis of airway inflammation and may be used as a potent agent for the treatment of asthma.