polysaccharides

ETHNOPHARMACOLOGICAL RELEVANCE

Polygala fallax Hemsl. is a traditional folk medicine commonly used by ethnic minorities in the Guangxi Zhuang Autonomous Region, and has a traditional application in the treatment of liver disease. Polygala fallax Hemsl. polysaccharides (PFPs) are of interest for their potential health benefits.

AIM OF THIS STUDY

This study explored the impact of PFPs on a mouse model of cholestatic liver injury (CLI) induced by alpha-naphthyl isothiocyanate (ANIT), as well as the potential mechanisms.

MATERIALS AND METHODS

A mouse CLI model was constructed using ANIT (80 mg/kg) and intervened with different doses of PFPs or ursodeoxycholic acid. Their serum biochemical indices, hepatic oxidative stress indices, and hepatic pathological characteristics were investigated. Then RNA sequencing was performed on liver tissues to identify differentially expressed genes and signaling pathways and to elucidate the mechanism of liver protection by PFPs. Finally, Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to verify the differentially expressed genes.

RESULTS

Data analyses showed that PFPs reduced the levels of liver function-related biochemical indices, such as ALT, AST, AKP, TBA, DBIL, and TBIL. PFPs up-regulated the activities of SOD and GSH, down-regulated the contents of MDA, inhibited the release of IL-1β, IL-6, and TNF-α, or promoted IL-10. Pathologic characterization of the liver revealed that PFPs reduced hepatocyte apoptosis or necrosis. The RNA sequencing indicated that the genes with differential expression were primarily enriched for the biosynthesis of primary bile acids, secretion or transportation of bile, the reactive oxygen species in chemical carcinogenesis, and the NF-kappa B signaling pathway. In addition, the results of qRT-PCR and Western blotting analysis were consistent with those of RNA sequencing analysis.

CONCLUSIONS

In summary, this study showed that PFPs improved intrahepatic cholestasis and alleviated liver damage through the modulation of primary bile acid production, Control of protein expression related to bile secretion or transportation, decrease in inflammatory reactions, and inhibition of oxidative pressure. As a result, PFPs might offer a hopeful ethnic dietary approach for managing intrahepatic cholestasis.

saponins on insomnia mice and their targets

ETHNOPHARMACOLOGICAL RELEVANCE

Polygala tenuifolia Willd. has been widely used in the treatment of cancer, forgetfulness, depression and other diseases.

AIM OF REVIEW

The purpose of this study was to investigate the sleep-enhancing effect and mechanism of P. tenuifolia saponins (PTS).

MATERIALS AND METHODS

The total saponin (YZ-I) and purified saponin (YZ-II) fractions were extracted and ICR mice model of insomnia was established by p-chlorophenylalanine (PCPA) induction to observe anxiety and depression behaviors. Effects of YZ-I and YZ-II on the levels of neurotransmitters, hormones, and inflammation cytokines were detected by ELISA, RT-qPCR and western blotting.

RESULTS

The results showed that YZ-I and YZ-II reduced the immobility time of mice and prolonged the sleep time of mice and significantly increased the concentrations of 5-HT, NE, PGD2, IL-1β and TNF-α. YZ-I and YZ-II regulated GABAARα2, GABAARα3, GAD65/67, 5-HT1A and 5-HT2A, while regulated the levels of inflammatory cytokines such as DPR, PGD2, iNOS and TNF-α to exert sedative and hypnotic effects.

CONCLUSION

PTS are mainly achieved sedative and hypnotic effects by altering serotonergic, GABAergic and immune systems, but the effects and mechanisms of action of YZ-I were different from YZ-II.

Phytochemical screening and antimicrobial activity of Polygala sadebeckiana Gürke extracts on bacterial isolates from Wound samples of patients with "Shimetere"

BACKGROUND

Modern medicine is not the choice of patients with "shimetere" in the Gurage community owing to their perception of 'parenteral medication use severely aggravates the disease'. For this reason, the root part of Polygala sadebeckiana Gürke is commonly utilized as traditional medicine in the management of the disease. The aim of this study was to evaluate the antimicrobial activity of Polygala sadebeckiana Gürke extract on bacterial isolates from wound samples of patients with "Shimetere".

METHODS

The agar well diffusion method was used to evaluate antibacterial activity, and the agar dilution method was utilized to determine minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MICs). The crude extract was tested against isolated bacteria at concentrations of 25, 50, 75 and 100 mg/mL in triplicate (3x). The positive controls were azithromycin (15 µg) and cloxacillin disk (5 µg), and the negative control was dimethylsulfoxide (5%). The group mean comparisons were made using one-way ANOVA at a significance level of p < 0.05, and the results are presented as the mean ± standard deviation. The presence of secondary metabolites from crude extract was checked by standard testing procedures.

RESULTS

S. aureus and S. pyrogen were the two identified bacteria from 9 (60%) and 3 (20%) wound samples, respectively. All identified bacterial strains were susceptible to the reference antibiotics. Tannins and saponins were the most abundant secondary metabolites found in the crude extracts. The average inhibition zones of the plant extracts with 100, 75, 50 and 25 mg/mL concentrations were 27, 20.33, 15.25, and 11.96 mm (p < 0.000) for S. aureus and 30.02, 24.50, 19.07, and 15.77 mm (p < 0.000) for S. pyrogen bacteria, respectively. The MIC and MBC of the crude extract were 1.67 and 10 mg/mL for S. aureus and 0.98 and 4 mg/mL for S. pyrogen.

CONCLUSION

Polygala sadebeckiana Gürke contained significant tannins and saponins as secondary metabolites and had antibacterial activities against isolated bacteria (S. aureus and S. pyrogen) from "Shimetere". The potential mechanism of antibacterial action of the plant extract was cell wall synthesis inhibition.

on Lipopolysaccharide-Stimulated RAW264.7 Cells

OBJECTIVE

To investigate the anti-oxidant and anti-inflammatory effects of ethanol extract of Polygala sibirica L. var megalopha Fr. (EEP) on RAW264.7 mouse macrophages.

METHODS

RAW264.7 cells were pretreated with 0-200 µg/mL EEP or vehicle for 2 h prior to exposure to 1 µg/mL lipopolysaccharide (LPS) for 24 h. Nitric oxide (NO) and prostaglandin (PGE2) production were determined by Griess reagent and enzyme-linked immunosorbent assay (ELISA), respectively. The mRNA levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), interleukin-1beta (IL-1β), and IL-6 were determined using reverse transcription polymerase chain reaction (RT-PCR). Western blot assay was used to determine the protein expressions of iNOS, COX-2, phosphorylation of extracellular regulated protein kinases (ERK1/2), c-Jun N-terminal kinase (JNK), inhibitory subunit of nuclear factor Kappa B alpha (Iκ B-α) and p38. Immunofluorescence was used to observe the nuclear expression of nuclear factor-κ B p65 (NF-κ B p65). Additionally, the anti-oxidant potential of EEP was evaluated by reactive oxygen species (ROS) production and the activities of catalase (CAT) and superoxide dismutase (SOD). The 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl (OH), superoxide anion (O2-) radical and nitrite scavenging activity were also measured.

RESULTS

The total polyphenol and flavonoid contents of EEP were 23.50±2.16 mg gallic acid equivalent/100 g and 43.78±3.81 mg rutin equivalent/100 g. With EEP treatment (100 and 150 µg/mL), there was a notable decrease in NO and PGE2 production induced by LPS in RAW264.7 cells by downregulation of iNOS and COX-2 mRNA and protein expressions (P<0.01 or P<0.05). Furthermore, with EEP treatment (150 µg/mL), there was a decrease in the mRNA expression levels of TNF-α, IL-1β and IL-6, as well as in the phosphorylation of ERK, JNK and p38 mitogen-activated protein kinase (MAPK, P<0.01 or P<0.05), by blocking the nuclear translocation of NF-κ B p65 in LPS-stimulated cells. In addition, EEP (100 and 150 µg/mL) led to an increase in the anti-oxidant enzymes activity of SOD and CAT, with a concomitant decrease in ROS production (P<0.01 or P<0.05). EEP also indicated the DPPH, OH, O2- radical and nitrite scavenging activity.

CONCLUSION

EEP inhibited inflammatory responses in activated macrophages through blocking MAPK/NF-κ B pathway and protected against oxidative stress.

Antiplasmodial activity of coumarins isolated from Polygala boliviensis: in vitro and in silico studies

Polygala boliviensis is found in the Brazilian semiarid region. This specie is little chemically and biologically studied. Polygala spp. have different metabolites, especially coumarins. Studies indicate that coumarins have antimalarial potential, denoting the importance of researching new active compounds from plants, since the resistance of Plasmodium strains to conventional therapy has increased. The present study aimed to evaluate the antiplasmodial activity of auraptene and poligalen against a chloroquine-resistant strain of Plasmodium falciparum. Coumarins were isolated from P. boliviensis by open column chromatography and identified by Nuclear Magnetic Resonance Spectroscopy. A cytotoxicity assay was carried out using MTT test, and the in vitro antiplasmodial activity was evaluated using the W2 strain. The antiplasmodial activity results found were IC50=0.171 ± 0.016 for auraptene and 0.164 ± 0.012 for poligalen; the selectivity indexes were 78.71 and 609.76, respectively. Inverse virtual screening in the BRAMMT database by OCTOPUS 1.2 was applied to coumarins to find potential P. falciparum targets and showed higher affinity energy of auraptene for purine nucleoside phosphorylase (PfPNP) and of poligalen for dihydroorotate dehydrogenase (PfDHODH). Molecular Dynamics studies (MD and MM-GBSA) approach were applied to calculate binding energies against selected P. falciparum targets and showed that all coumarins were stable at the binding site during simulations. Furthermore, energies were favorable for complexation. This is the first report of auraptene in P. boliviensis species and of in vitro antiplasmodial activity of auraptene and poligalen. In silico studies indicated that the mechanism of action of coumarins is the inhibition of PfPNP and PfDHODH.Communicated by Ramaswamy H. Sarma.

Therapeutic potential of Polygala saponins in neurological diseases

BACKGROUND

There are many types of neurological diseases with complex etiologies. At present, most clinical drugs can only relieve symptoms but cannot cure these diseases. Radix Polygalae, a famous traditional Chinese medicine from the root of plants of the genus Polygala, has the traditional effect of treating insomnia, forgetfulness, and palpitation and improving intelligence and other symptoms of neurological diseases. Saponins are important bioactive components of plants of the genus Polygala and exhibit neuroprotective effects.

PURPOSE

This review aimed to summarize the traditional use of Polygala species and discuss the latest phytochemical, pharmacological, and toxicological findings, mainly with regard to Polygala saponins in the treatment of neurological disorders.

METHODS

Literature was searched and collected using databases, including PubMed, Science Direct, CNKI, and Google Scholar. The search terms used included "Polygala", "saponins", "neurological diseases", "Alzheimer's disease", "toxicity", etc., and combinations of these keywords. A total of 1202 papers were retrieved until August 2022, and we included 135 of these papers on traditional uses, phytochemistry, pharmacology, toxicology and other fields.

RESULTS

This literature review mainly reports on the traditional use of the Polygala genus and prescriptions containing Radix Polygalae in neurological diseases. Phytochemical studies have shown that plants of the genus Polygala mainly include saponins, flavonoids, oligosaccharide esters, alkaloids, coumarins, lignans, flavonoids, etc. Among them, saponins are the majority. Modern pharmacological studies have shown that Polygala saponins have neuroprotective effects on a variety of neurological diseases. Its mechanism of action involves autophagic degradation of misfolded proteins, anti-inflammatory, anti-apoptotic, antioxidative stress and so on. Toxicological studies have shown that Polygala saponins trigger gastrointestinal toxicity, and honey processing and glycosyl disruption of Polygala saponins can effectively ameliorate its gastrointestinal side effect.

CONCLUSION

Polygala saponins are the major bioactive components in plants of the genus Polygala that exhibit therapeutic potential in various neurological diseases. This review provides directions for the future study of Polygala saponins and references for the clinical use of prescriptions containing Radix Polygalae for the treatment of neurological diseases.

Polygalae Radix shortens the circadian period through activation of the CaMKII pathway

CONTEXT

The mammalian circadian clock system regulates physiological function. Crude drugs, containing Polygalae Radix, and Kampō, combining multiple crude drugs, have been used to treat various diseases, but few studies have focussed on the circadian clock.

OBJECTIVE

We examine effective crude drugs, which cover at least one or two of Kampō, for the shortening effects on period length of clock gene expression rhythm, and reveal the mechanism of shortening effects.

MATERIALS AND METHODS

We prepared 40 crude drugs. In the in vitro experiments, we used mouse embryonic fibroblasts from PERIOD2::LUCIFERASE knock-in mice (background; C57BL/6J mice) to evaluate the effect of crude drugs on the period length of core clock gene, Per2, expression rhythm by chronic treatment (six days) with distilled water or crude drugs (100 μg/mL). In the in vivo experiments, we evaluated the free-running period length of C57BL/6J mice fed AIN-93M or AIN-93M supplemented with 1% crude drug (6 weeks) that shortened the period length of the PERIOD2::LUCIFERASE expression rhythm in the in vitro experiments.

RESULTS

We found that Polygalae Radix (ED₅₀: 24.01 μg/mL) had the most shortened PERIOD2::LUCIFERASE rhythm period length in 40 crude drugs and that the CaMKII pathway was involved in this effect. Moreover, long-term feeding with AIN-93M+Polygalae Radix slightly shortened the free-running period of the mouse locomotor activity rhythm.

DISCUSSION AND CONCLUSIONS

Our results indicate that Polygalae Radix may be regarded as a new therapy for circadian rhythm disorder and that the CaMKII pathway may be regarded as a target pathway for circadian rhythm disorders.

slows the progression of diabetic nephropathy by targeting TLR4 anti-inflammation and MMP-2/9-mediated anti-fibrosis in vitro

BACKGROUND

Polygala fallax Hemsl. is a plant that is commonly used as a folk medicine by Guangxi ethnic minorities, and it is also widely used in the clinical treatment of chronic diseases in China. The extract of P. fallax (EPF) contains key biologically active components from the roots and stems. However, the role of P. fallax or EPF in diabetic nephropathy (DN) is unclear.

PURPOSE

This study aimed to investigate the effects and mechanisms of EPF on high glucose (HG)-induced human glomerular mesangial cell (HMC) injury, inflammation, fibrosis, and apoptosis in vitro.

METHODS

For the in vitro study, MTT and ELISA assays were performed with HG-treated HMCs, as well as MMP, Hoechst, flow cytometry, qRT-PCR, and western blot analyses. The expression of the TLR4/NF-κB pathway, along with its downstream inflammatory, apoptosis, and fibrosis factors, was measured. The expression of the TLR4/NF-κB pathway and its downstream inflammatory factors were also measured after the addition of TLR4 inhibitors.

RESULTS

Our results suggest that EPF can reverse the hyperproliferation and apoptosis of HMCs induced by HG. In addition, the extract inhibited the increase in inflammatory factors IL-6, TNF-α, IL-1β, MCP-1, and IL-18 in cells treated with HG. The mRNA and protein expression of TLR4, MyD88, NF-κB, Col IV, FN, MMP-9, and MMP-2 were downregulated by EPF. In addition, EPF significantly reduced the loss of MMP and the upregulation of Bcl-2/Bax mRNA and protein levels after HG treatment.

CONCLUSION

These results demonstrated that EPF protects against diabetes-induced renal injury in vitro. EPF protected against HG-induced HMCs proliferation, apoptosis, fibrosis, and inflammation likely via inhibition of TLR4-dependent NF-κB signaling. This herbal extract may also be a novel treatment for DN.

Polygala saponins inhibit NLRP3 inflammasome-mediated neuroinflammation via SHP-2-Mediated mitophagy

Activation of the NLRP3 inflammasome and its mediated neuroinflammation are implicated in neurodegenerative diseases, while mitophagy negatively regulates NLRP3 inflammasome activation. SHP-2, a protein-tyrosine phosphatase, is critical for NLRP3 inflammasome regulation and inflammatory responses. In this study, we investigated whether triterpenoid saponins in Radix Polygalae inhibit the NLRP3 inflammasome via mitophagy induction. First, we isolated the active fraction (polygala saponins (PSS)) and identified 17 saponins by ultra-performance liquid chromatography coupled with diode-array detection and tandem quadrupole time-of-flight mass spectrometry (UHPLC-DAD-Q/TOF-MS). In microglial BV-2 cells, PSS induced mitophagy as evidenced by increased co-localization of LC3 and mitochondria, as well as an increased number of autophagic vacuoles surrounding the mitochondria. Furthermore, the mechanistic study found that PSS activated the AMPK/mTOR and PINK1/parkin signaling pathways via the upregulation of SHP-2. In Aβ(1-42)-, A53T-α-synuclein-, or Q74-induced BV-2 cells, PSS significantly inhibited NLRP3 inflammasome activation, which was attenuated by bafilomycin A1 (an autophagy inhibitor) and SHP099 (an SHP-2 inhibitor). In addition, the co-localization of LC3 and ASC revealed that PSS promoted the autophagic degradation of the NLRP3 inflammasome. Moreover, PSS decreased apoptosis in conditioned medium-induced PC-12 cells. In APP/PS1 mice, PSS improved cognitive function, ameliorated Aβ pathology, and inhibited neuronal death. Collectively, the present study, for the first time, shows that PSS inhibit the NLRP3 inflammasome via SHP-2-mediated mitophagy in vitro and in vivo, which strongly suggests the therapeutic potential of PSS in various neurodegenerative diseases.

Root Using a Hydrolytic Continuous Flow System under High-Temperature, High-Pressure Conditions

An improved process for preparing tenuifolin (presenegenin 3-β-d-glucopyranoside) from the root of Polygala senega L. was developed. A crude saponin mixture extracted from P. senega was subjected to hydrolysis, and the reactivity of compounds in the extract was controlled by utilizing the combination of a flow reactor and experimental design. In addition, column chromatography with HP 20, a synthetic polystyrenic adsorbent, allowed the gram-scale preparation of tenuifolin in a continuous manner with fewer steps. This approach shortens the total time required for gram-scale preparation from 16 to 5 h in a continuous manner while improving the yield from 0.59% to 2.08% (w/w).

Bennett extract mitigates motor and cognitive deficits in a mouse model of acute ischemia

Stroke is considered one of the leading causes of death worldwide. The treatment is limited; however, the Brazilian flora has a great source of natural products with therapeutic potentials. Studies with the medicinal plant Polygala sabulosa W. Bennett provided evidence for its use as an anti-inflammatory and neuroprotective drug. In the case of ischemic stroke due to lack of oxygen, both acute and chronic inflammatory processes are activated. Thus, we hypothesized that P. sabulosa (HEPs) has the potential to treat the motor and cognitive deficits generated by ischemic stroke. Male mice were subjected to global ischemia for 60 min, followed by reperfusion and orally treated with HEPs (100 mg/kg in saline + 3% tween 20) twice a day (12 h apart) for 48 h starting 3 h after surgery. Motor skills were assessed using grip force and open field tasks. Hippocampi were then collected for mRNA quantification of the cytokines IL-1-β and TNF-α levels. After 48 h of acute treatment, spatial reference memory was evaluated in a Morris water maze test for another group of animals. We show that HEPs treatment significantly prevented motor weakness induced by ischemia. Brain infarct area was reduced by 22.25% with downregulation of the levels of IL-1β and TNF-α mRNA. Learning performance and memory ability on Morris water maze task were similar to the sham group. Our data demonstrates the neuroprotective properties of HEPs through its anti-inflammatory activities, which prevent motor and cognitive impairments, suggesting that HEPs may be an effective therapy for ischemic stroke.

Extract of the Aerial Part of Polygala tenuifolia Attenuates d-Galactose/NaNO2-induced Learning and Memory Impairment in Mice

Alzheimer's disease, one of the most common types of age-related dementia, is characterized by memory deterioration and behavior disorder. The aboveground part of Polygala tenuifolia is a traditional Chinese medicine used for the treatment of amnesia. This study was conducted to investigate the ameliorating effect of the aerial part of P. tenuifolia on d-galactose/NaNO₂-induced learning and memory impairment in mice. d-galactose (120 mg/kg) and NaNO₂ (90 mg/kg) were injected intraperitoneally for 60 days to induce learning and memory impairment in mice. The aerial part of P. tenuifolia (25, 50, and 100 mg/kg) and piracetam (200 mg/kg) were simultaneously administered orally on days 15 - 60. Results of this study showed that aerial part of P. tenuifolia significantly decreased the latency time and increased the number of platform crossings in the Morris water maze compared with the Model group. Moreover, the aerial part of P. tenuifolia significantly increased the latency time and decreased the error frequency in the step-down and step-through tests compared with the Model group. Meanwhile, the aerial part of P. tenuifolia was able to regulate the cholinergic system by increasing the levels of ACh and ChAT and decreasing the level of AChe. The aerial part of P. tenuifolia also significantly attenuated the levels of interleukin-1 beta and malonaldehyde and enhanced the interleukin-10 and glutathione levels and superoxide dismutase activity. Furthermore, treatment with aerial part of P. tenuifolia increased the protein and mRNA expression of brain-derived neurotrophic factor and tropomyosin receptor kinase B in the hippocampus. These results suggest that the aerial part of P. tenuifolia can ameliorate learning and memory impairments by modulating cholinergic activity, inhibiting neuroinflammation and oxidative stress, and regulating the brain-derived neurotrophic factor and tropomyosin receptor kinase B signaling pathway.

Polygala tenuifolia: a source for anti-Alzheimer's disease drugs

Context: Alzheimer's disease (AD) is a chronic neurodegenerative disease that originates from central nervous system lesions or recessions. Current estimates suggest that this disease affects over 35 million people worldwide. However, lacking effective drugs is the biggest handicap in treating AD. In traditional Chinese medicine (TCM), Polygala tenuifolia Willd. (Polygalaceae) is generally used to treat insomnia, memory dysfunction and neurasthenia.Objective: This review article explores the role of P. tenuifolia and its active components in anti-Alzheimer's disease.Methods: Literature for the last ten years was obtained through a search on PubMed, SciFinder, CNKI, Google Scholar, Web of Science, Science Direct and China Knowledge Resource Integrated with the following keywords: Polygala tenuifolia, polygalasaponin XXXII (PGS 32), tenuifolin, polygalacic acid, senegenin, tenuigenin, Alzheimer's disease.Results: Polygala tenuifolia and its active components have multiplex neuroprotective potential associated with AD, such as anti-Aβ aggregation, anti-Tau protein, anti-inflammation, antioxidant, anti-neuronal apoptosis, enhancing central cholinergic system and promote neuronal proliferation.Conclusions: Polygala tenuifolia and its active components exhibit multiple neuroprotective effects. Hence, P. tenuifolia is a potential drug against Alzheimer's disease, especially in terms of prevention.

Assessment of Polygala paniculata (Polygalaceae) characteristics for evolutionary studies of legume-rhizobia symbiosis

Root nodule (RN) symbiosis is a mutualistic interaction observed between nitrogen-fixing soil bacteria and nodulating plants, which are scattered in only four orders of angiosperms called nitrogen-fixing clade. Most of legumes engage in RN symbiosis with rhizobia. Molecular genetic analyses with legumes and non-leguminous nodulating plants revealed that RN symbiosis utilizes early signalling components that are required for symbiosis with arbuscular mycorrhizal (AM) fungi. However detailed evolutionary processes are still largely unknown. Comparative analyses with non-nodulating species phylogenetically related to legumes could be better strategies to study the evolution of RN symbiosis in legumes. Polygala paniculata is a non-leguminous species that belongs to a family different from legumes but that is classified into the same order, Fabales. It has appropriate characteristics for cultivation in laboratories: small body size, high fertility and short lifecycles. Therefore, we further assessed whether this species is suitable as a model species for comparative studies with legumes. We first validated that the plant we obtained in Palau was truly P. paniculata by molecular phylogenetic analysis using rbcL sequences. The estimated genome size of this species was less than those of two model legumes, Lotus japonicus and Medicago truncatula. We determined conditions for cultivation in vitro and for hairy root formation from P. paniculata seedlings. It would facilitate to investigate gene functions in this species. The ability of P. paniculata to interact with AM fungi was confirmed by inoculation with Rhizophagus irregularis, suggesting the presence of early signalling factors that might be involved in RN symbiosis. Unexpectedly, branching of root hairs was observed when inoculated with Mesorhizobium loti broad host range strain NZP2037, indicating that P. paniculata has the biological potential to respond to rhizobia. We propose that P. paniculata is used as a model plant for the evolutionary study of RN symbiosis.

Study on the safety of Polygala tenuifolia Willdenow root extract powder (BT-11) in young person aged from 9 to 19 years old

ETHNOPHARMACOLOGICAL RELEVANCE

Polygala tenuifolia Willdenow root extract (BT-11) has beneficial effects on central nervous system disorders in human. The safety of BT-11 should be elucidated in younger person further.

AIM OF THE STUDY

To evaluate the safety of BT-11 in human aged from 9 to 19 years old.

MATERIAL AND METHODS

The safety was evaluated in randomly assigned subjects who received the test products (61 subjects in BT-11 300 mg daily or 60 subjects in matching placebo) for 12 weeks. Adverse reactions were analyzed by the incidence rate, type, and severity. The clinical examination included hematology and blood chemistry tests, urinalysis, vital signs, body weight, and electrocardiogram (ECG).

RESULTS

Eleven adverse reactions were observed in ten subjects receiving BT-11 while seven adverse reactions in six subjects receiving placebo. There were no statistical differences in the incidence of adverse reactions between the two groups. Serious adverse reactions such as acute appendicitis and acute viral gastroenteritis were observed in the BT-11 group4 and the placebo group, respectively. However, it was confirmed that they were not associated with the test product. All other adverse reactions observed during the test period were resolved completely without special treatment. No statistical difference was also observed in safety laboratory tests, vital signs, and ECG between two groups.

CONCLUSIONS

This study demonstrates the safety of BT-11 in the adolescent by showing no apparent adverse reactions related to it.

Effects of pre-slaughter stressor and feeding preventative Chinese medicinal herbs on glycolysis and oxidative stability in pigs

A total of 64 5-month-old Pietrain pigs were randomly allocated to four treatments with four replicates per treatment according to body weight. The pigs were fed either a standard corn-soybean meal based control diet (treatments 1 and 2), the standard diet with 1% Lycium barbarum (LB) (treatment 3), or the standard diet with 1% Polygala tenuifolia Willd (PT) (treatment 4). Serum lactic acid and glucose concentrations were increased in stressed pigs (P < 0.05). Addition of the herbs in the diet had no effect on the serum lactic acid concentration, but 1% LB decreased (P < 0.05) serum glucose concentration in the stressed pigs. Pre-slaughter stress also decreased (P < 0.01) liver glycogen concentration and the decrease could be inhibited by addition of 1% LB in the diet (P > 0.05). Pre-slaughter stress increased the concentration of maleic dialdehyde (MDA) (P < 0.05) and decreased glutathione peroxidase (GSH-Px) activity in serum, while dietary 1% LB increased (P < 0.05) the activity of GSH-Px and decreased the concentration of MDA in the serum. In conclusion, pre-slaughter stress induces oxidative stress in pigs and dietary supplementation with 1% LB improves antioxidant capacity in stressed pigs before slaughtering.

[Chemical constituents of Polygala tenuifolia root]

OBJECTIVE

To study the chemical constituents from the root of Polygala tenuifolia.

METHODS

Silica gel,Sephadex LH-20 and ODS chromatographic techniques were used to study the chemical constituents of Polygala tenuifolia, and the chemical structures were elucidated by application of spectral data.

RESULTS

Eight-compounds were obtained and their structure were identified as 7-hydroxy-1-methoxy-2,3-methylenedioxyxanthone(1), 1, 7-dihydroxy-2, 3-dimethoxyxanth one(2), 1,3,6-trihydroxy-2, 7-dimethoxyxanthone(3),7-hydroxy-1,2, 3-trimethoxyxanthone(4), 1,2,3,6, 7-pentamethoxyxanthone(5), 1,3, 7-trihydroxy-2, 6-dimethanoxyxanthone (6),7-hydroxy-1-methoxyxanthone(7) and 1,7-dihydroxy-3,4-dimethoxyxanthone(8).

CONCLUSION

Compounds 1,6,7 and 8 are isolated from Polygala tenuifolia for the first time.

Morpho-anatomical and molecular characterization of the mycorrhizas of European Polygala species

The mycorrhizas of 12 species of Polygala (Polygalaceae), including herbs, subshrubs and one shrub, collected from Germany, Mallorca (Spain) and Malta, were investigated by morpho-anatomical and molecular methods. Aseptate hyphae, arbuscules and vesicles indicate an arbuscular mycorrhiza in all species examined. Hyphal spread in Polygala is predominantly, but not exclusively, intracellular and comprises three characteristic stages of colonization: (i) intracellular, linear hyphal growth in a cascading manner after penetration towards the penultimate parenchyma layer (layer 2), (ii) initially linear hyphal growth in the cells of layer 2 from where hyphal branches repeatedly penetrate the anatomically distinct innermost parenchyma layer (layer 1), forming arbuscule-like structures therein which are subject to degeneration, (iii) more branches from the linear hyphae in layer 2 develop, but coil and make contact to the layer outside layer 2 (layer 3) in which arbuscule-like structures similar to those in layer 1 form and degenerate. This general colonization pattern differs in details between the species, and critical comparisons, in particular between the woody P. myrtifolia, the herbaceous Polygala spp. and the mycoheterotrophic Epirixanthes spp. (Polygalaceae) suggest an evolutionary shift of mycorrhizal features within the family towards an optimization of plant benefit through the fungus. Based on the molecular marker 18S rDNA mycorrhizal fungi detected in roots of Polygala spp. are largely restricted to five clades of Glomeraceae 1 (Glomus Group A). This result rejects the hypothesis of a strict symbiotic specificity in Polygalaceae but may stimulate a discussion on functionally compatible groups of fungi.

Pharmacological Properties of N-095, a Drug Containing Red Ginseng, Polygala Root, Saffron, Antelope Horn and Aloe Wood

This study sought to establish a pharmacological profile for N-095, a crude drug containing red ginseng, polygala root, saffron, antelope horn and aloe wood. Our studies on rats and mice revealed a number of pharmacological properties of this novel drug. N-095 increased the forced swimming time in mice and prevented gastric ulcers in rats under restraint and water immersion stress conditions at 100 mg/kg or higher. It also prevented footpad swelling in rats treated with λ-carrageenin and histamine-induced gastric ulcers in rats at 300 mg/kg or higher. Furthermore, N-095 augmented the sedative effect in mice induced by hexobarbital, which is characterized by a decreased spontaneous motor activity and a prolongation of sleeping time. N-095 also stimulated spontaneous contractility of the uterus in rats at 1000 mg/kg and 2000 mg/kg and prevented hemolysis of erythrocytes by heating. In contrast, N-095 had no effect on the respiratory or cardiovascular system or on water and electrolyte regulation in rats or mice. These results show that N-095 is a relatively safe drug for use as a nutrient or tonic.

[Study on acute toxicity test of different processed products of Radix polygalae]

OBJECTIVE

To study the acute toxicity of the water extracts (ERWE) and 60% ethanol extracts (EREE) from different processed products of Radix Polygalae (crude Radix Polygalae, licorice, and honey processed Radix Polygalae), thus providing scientific evidence for toxicity study of Radix Polygalae and its safe clinical application.

METHODS

The ERWE and EREE were prepared from different processed products of Radix Polygalae. Their contents of saponins were respectively determined. The poisoning condition and death of the mice administered with ERWE and EREE by gastrogavage were observed within fourteen days. The modified Karber's method was used to calculate LD50 and 95% confidence interval (CI).

RESULTS

The EREE of licorice processed Radix Polygalae had the maximum toxicity with highest content of saponins, while the ERWE of honey processed Radix Polygalae had the minimum toxicity with lowest content of saponins.

CONCLUSIONS

Different processing methods have effects on the contents of saponins in Radix Polygalae. The experiment showed that the toxicity of Radix Polygalae is in direct proportion to the content of saponins. The higher the saponins contents, the higher the toxicity.

Polygalae radix inhibits toxin-induced neuronal death in the Parkinson's disease models

AIM OF THE STUDY

Polygalae radix, the root of Polygala tenuifolia Willd, has commonly been used for the treatment of amnesia and anxiety in traditional Korean medicine. The aim of this study was to investigate its neuroprotective effects and possible mechanisms of action in models of Parkinson's disease.

MATERIALS AND METHODS

This study utilized a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, a reactive oxygen species (ROS) assay, a nitric oxide (NO) production assay, and a caspase-3 activity test as measures of cell viability in PC12 cells damaged by 6-hydroxydopamine (6-OHDA). The protective effects of PRE against 1-methyl-4-phenylpyridium (MPP(+))-induced neurotoxicity were assessed in rat primary dopaminergic neurons and in a mouse PD model in which PRE was administered (100mg/kg/day, 3 days, p.o.) before acute 1-mehtyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity. Finally, TH immunohistochemistry tests were conducted in the substantia nigra pars compacta (SNpc) and striatum (ST).

RESULTS AND CONCLUSIONS

PRE significantly inhibited 6-OHDA-induced cell damage at doses of 0.05-1μg/ml with a maximal effect at 0.1μg/ml. Caspase-3 activity and the production of ROS and NO were alleviated at 0.1μg/ml. Also at this dose, PRE protected mesencephalic dopaminergic neurons from MPP(+)-induced toxicity. In an in vivo mouse model of PD, PRE protected dopaminergic neurons and fibers from MPTP-induced toxicity in the SNpc and ST. These results demonstrate that PRE has protective effects on dopaminergic neurons via its anti-oxidant and anti-apoptotic activity.

The effect of Acorus gramineus on the bioavailabilities and brain concentrations of ginsenosides Rg1, Re and Rb1 after oral administration of Kai-Xin-San preparations in rats

AIM OF THE STUDY

To investigate the effect of Acorus gramineus (AG), a supposed 'delivering servant' according to traditional Chinese medicine principles governing multi-herb formula preparation and formulation, on facilitating the uptake of ginsenosides Rg1, Re and Rb1 to the brain after oral administration of Kai-Xin-San (KXS) preparations.

MATERIALS AND METHODS

Ginseng extracts or KXS with or without AG were administered to rats for pharmacokinetic study and mice for behaviour tests at a dose of 3 g ginseng per kg. The concentrations of ginsenosides in plasma and brain were determined by an LC-MS/MS method, whilst the effects of preparations on spatial learning were evaluated using the Morris water maze test.

RESULTS

KXS in the presence of AG tended to significantly reverse the learning impairment induced by scopolamine. The presence of AG in the KXS formula led to increases in the initial absorption rate and extent of Rg1 and Re in terms of Cmax1 and AUC(0-3h) compared to KXS without AG. Although KXS were found to increase the bioavailabilities and brain concentrations of ginsenosides relative to ginseng extract, the brain-to-plasma AUC(0-12h) ratios appeared not to be affected.

CONCLUSIONS

The results suggested that the presence of AG in the KXS formula promoted the initial absorption of ginsenosides Rg1 and Re in the gastrointestinal tract, but unlikely affected the brain-to-plasma AUC ratios.

Antioxidant activity of oligosaccharide ester extracted from Polygala tenuifolia roots in senescence-accelerated mice

The constituents of the ethanol extract from the root of Polygala tenuifolia Willd. (Polygalaceae) were investigated for antioxidant activity in senescence-accelerated mice. Consequently, two relevant samples were obtained, a fraction separated by macroporous resin (YZ-OE), and a major pure crystal of 3,6'-disinapoyl sucrose (DISS). Based on HPLC-ESI-MS analysis, the most constituents in the YZ-OE fraction from the extract of P. tenuifolia were oligosaccharide esters. The antioxidant activities of these two samples were evaluated using the accelerated senescence-prone, short-lived mice (SAMP) in vivo. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) were increased significantly in SAMP mice fed oligosaccharide esters (YZ-OE 50 mg/kg) and its constituents (DISS 50 mg/kg). However, the content of malondialdehyde (MDA) was increased in the blood and liver of SAMP mice. But when given YZ-OE, it could be decreased, by 44.3% and 47.5%, respectively, compared with the SAMP model. Results from the analyses indicated that the oligosaccharide esters (YZ-OE) from roots of P. tenuifolia had a high in vivo antioxidant activity.

Antidepressant effects of the extract YZ-50 from Polygala tenuifolia in chronic mild stress treated rats and its possible mechanisms

YZ-50 is an active fraction obtained from the root of Polygala tenuifolia Willd. (Polygalaceae) extract and it has been reported previously to exert beneficial effects on mental health in depressed sufferers, however, its mechanism of action remains unresolved. This study utilized the chronic mild stress (CMS) model of depression in Sprague-Dawley rats to evaluate the effects of YZ-50 on depressive behaviors. Furthermore, we tested the hypothesis that the capacity of YZ-50 to reverse the harmful effects of CMS is relative to the hypothalamo-pituitary-adrenal (HPA) system and brain-derived neurotrophic factor (BDNF) in the hippocampus. Repeated administration of YZ-50 for 28 days at the doses of 140 and 280 mg/kg in CMS, YZ-50 reversed the CMS-induced changes in sucrose consumption, plasma corticosterone levels and open field activity. In addition, CMS significantly decreased hippocampal BDNF mRNA levels. However, YZ-50 counteracted a decrease in hippocampal BDNF mRNA caused by CMS. In conclusion, YZ-50 reversed the harmful effects of CMS on mood and behaviors in rats and it possesses an antidepressant property that is at least in part mediated by the neuroendocrine and neuropropective systems, and it is likely that the HPA system plays an important role in this process.

Anxiolytic and sedative-hypnotic activities of polygalasaponins from Polygala tenuifolia in mice

In the present study, the anxiolytic and sedative-hypnotic activities of polygalasaponins extracted from Polygala tenuifolia Willdenow (Polygalaceae) were determined in mice using hole-board, elevated plus maze, open field, and sodium pentobarbital-induced hypnosis tests. Moreover, the acute toxicity of polygalasaponins was also estimated in mice. Sixty minutes after p.o. administration of polygalasaponins (40, 80, 160 mg/kg) in mice, the central crossing counts and percentage of central/total ambulation significantly increased and the number of rearings and defecations was evidently inhibited in the open field test. Polygalasaponins also increased the head-dips of mice in the hole-board test and the time spent by mice in the open arms of the X-maze, prolonged sleep duration and shortened sleep latency in the test of synergetic effect on sodium pentobarbital (45 and 25 mg/kg, respectively). Acute toxic study showed the oral median lethal dose (LD(50)) of polygalasaponins was 3.95 g/kg and 0% lethal dose 2.6 g/kg. These results suggest that polygalasaponin possesses evident anxiolytic and sedative-hypnotic activities and has a relatively safe dose range, which supports the use of Polygala tenuifolia root as an anxiolytic and sedative-hypnotic drug in folk medicine.

Tenuifolin, an extract derived from tenuigenin, inhibits amyloid-beta secretion in vitro

AIM

Previous studies have shown that tenuigenin, a crude extract of Polygala tenuifolia Willd. that is commonly used in traditional Chinese herbal medicine for memory loss, can reduce the secretion of Abeta from cultured cells. However, the mechanism underlying this effect and the active compound derived from tenuigenin is unknown. In this study, a purified component of tenuigenin, tenuifolin, was examined and revealed to be an effective compound in vitro.

METHODS

Abeta secretion from three sets of COS-7 cells, each carrying a plasmid expressing a different form of APP was examined following the treatment with tenuifolin. Initially, tenuifolin was determined to have no inherent toxicity to either the transfected or wild type cells at the effective concentrations. Cells were then treated with 0.5-2.0 microg mL(-1) tenuifolin for 12 h and their media were examined via an ELISA for Abeta1-40 and Abeta-42.

RESULTS

We found that treatment with 2.0 microg mL(-1) tenuifolin significantly decreased Abeta secretion from COS-7 cells without altering the ratio of Abeta1-40 and Abeta-42. This effect is most probably due to inhibition of the beta-site APP cleaving enzyme as Abeta secretion was not inhibited from cells expressing the C99 fragment.

CONCLUSION

Tenuifolin is an effective compound from tenuigenin. We believe that this finding should lead the way for future experiments to determine the exact mechanism for tenuifolin's effect on Abeta secretion.

Preventive action of Kai Xin San aqueous extract on depressive-like symptoms and cognition deficit induced by chronic mild stress

Kai Xin San (KXS), a traditional Chinese herbal medicine, has been used clinically for the treatment of depressive disorders and cognitive impairment for centuries. However, the effects of KXS on cognitive dysfunction induced by depression have not been evaluated scientifically. The present study aimed to explore the antidepressant-like and nootropic effects of an aqueous extract of KXS (at doses of 0.3, 0.9, and 2.7 g/kg/day) using chronic mild stress (CMS) as a model of depression. Depressive symptoms were analyzed using the sucrose-preference and novelty-induced inhibition of feeding tests. Cognitive function was evaluated using a two-way active avoidance task. Serum corticosterone and adrenocorticotropic hormone (ACTH) levels, acetylcholinesterase (AChE) protein expression in the hippocampus, and monoamine neurotransmitter concentrations in the prefrontal cortex and hippocampus were also determined to elucidate the neurochemical mechanisms. Experimental results showed that KXS aqueous extract significantly ameliorated the CMS-induced depressive symptoms, including the reduced preference index and prolonged latency to novelty-suppressed feeding. Simultaneously, KXS significantly reversed the CMS-induced decrease in the numbers of active avoidance and active movement distances and increase in the numbers of the passive avoidance and passive movement distances, thereby producing nootropic effects in the two-way active avoidance test. KXS also inhibited the increased AChE expression in the hippocampus, up-regulated the decreased monoamine neurotransmitter concentrations of both brain areas and reduced the elevated ACTH concentrations in the serum induced by CMS. Taken together, these results indicate that KXS exerts its antidepressant-like and nootropic effects in the CMS model by modulating the HPA axis, monoamine neurotransmitter and cholinergic systems.

Hepatoprotective activity of the Indian medicinal plant Polygala arvensis on d-galactosamine-induced hepatic injury in rats

The suspensions of chloroform extract of leaves in 0.3% carboxy methyl cellulose (CMC) was evaluated for hepatoprotective activity in Wistar albino rats by inducing hepatic injury with d-galactosamine (400 mg/kg). The chloroform extract of Polygala arvensis at an oral dose of 200 mg/kg and 400 mg/kg exhibited a significant (P<0.001, P<0.01 and P<0.05) protection effect by normalizing the levels of aspartate amino transferase (ASAT, GOT), alanine amino transferase (ALAT, GPT), alkaline phosphatase (ALP), total bilirubin (TB), lactate dehydrogenase (LDH), total cholesterol (TC), triglycerides (TGL), albumin, total protein (TP) which were significantly (P<0.001) increased in rats by treatment with 400 mg/kg i.p. of d-galactosamine. Silymarin (25 mg/kg), a known hepatoprotective drug used for comparison exhibited significant activity (P<0.001).

Effect of Polygala tenuifolia root extract on cerebral ischemia and reperfusion

In this study, the effects of Polygala tenuifolia root extract on brain ischemia/reperfusion injury in Mongolian gerbils were investigated. The gerbils were administered ethanol extract of P. tenuifolia and its four sub-fractions orally 2 hours prior to ischemia, and were subjected to a 20-minute no-flow cerebral ischemia in vivo. Thirty minutes and 72 hours after reperfusion, the brain was removed and the ATP, lactate and lipid peroxide levels were determined, and the neurons in the hippocampal CA1 subfield were examined. In the vehicle-treated ischemic gerbils, the brain ATP levels decreased significantly, but this decrease was prevented by pre-treatment with an n-butanol fraction of P. tenuifolia. In contrast, both the lactate content and lipid peroxidation levels were elevated in the vehicle-treated ischemic animals, but this elevation was inhibited by ethanol extract and n-butanol fraction of P. tenuifolia, respectively. Both the ethanol extract and n-butanol fraction of P. tenuifolia attenuated post-ischemic neuronal necrosis in the hippocampal CA1 subfield. Our findings suggest that both ethanol extract and n-butanol fraction of P. tenuifolia root can reduce brain damage during ischemia and reperfusion, and prevent lipid peroxidation and preserve the energy metabolism.

New flavonol glycosides and new xanthone from Polygala japonica

Three new flavonol glycosides and a new xanthone were isolated from Polygala japonica HOUTT. with eight known compounds. Their structures were identified as 1,7-dihydroxy-3,4-dimethoxy-xanthone (1), kaempferol-7,4'-dimethyl ether (2), physcion (3), guazijinxanthone (4), rhamnetin (5), polygalin A (6), 3,5,7-trihydroxy-4'-methoxy-flavone-3-O-beta-d-galactopyranoside (7), 3,5,3'-trihydoxy-7,4'-dimethoxy-flavone-3-O-beta-d-galactopyranoside (8), 3,5,3',4'-tetrahydroxy-7-methoxy-flavone-3-O-beta-d-galactopyranoside (9), 3,5,3',4'-tetrahydroxy-7-methoxy-flavone-3-O-beta-d-glucopyranoside (10), polygalin B (11), polygalin C (12). Among them, compound 4 is a new xanthone, and 6, 11 and 12 are new flavonol glycosides. Compounds 1, 4, 7 and 8 were tested for cytotoxic activity with MTT assays on five human tumor cell lines, K562, A549, PC-3M, HCT-8 and SHG-44. Compound 4 showed cytotoxic activity against all the five cell lines.

A new cerebroside from Polygala japonica

The isolation of a new cerebroside, 1-O-beta-d-glucopyranosyl-(2S,3S,4R,11E)-2-[(2'R)-2'-hydroxypalmitoylamino]-11-octadecene-1,3,4-triol (polygalacerebroside) (1), from the aerial part of Polygala japonica is reported.

Antiinflammatory activity of Polygala japonica extract

The antiinflammatory activity of the aqueous extract of Polygala japonica (AEPJ) was investigated in mice and rats to find the pharmacological basis for its ethnomedical use. The extract produced a significant inhibition of peritoneal and cutaneous vascular permeability induced by acetic acid and histamine, respectively and ear swelling induced by picryl chloride in mice at the dose of 25.0 mg/kg. Moreover, the extract markedly inhibited footpad edema induced by histamine in rats, and decreased prostaglandin E(2) (PGE(2)) content in carrageenan-induced air-pouch at doses of 12.5 and 6.25 mg/kg respectively.

Antagonistic effects of methanolic extract of Polygala telephioides on morphine responses in mice

The present study was undertaken to investigate the antagonistic effects of the methanolic extract of Polygala telephioides (PT) on morphine responses in mice. Single administration of PT tended to antagonize the morphine-induced analgesia in a hot-plate test. Moreover, PT (300 mg/kg, p.o.) improved the morphine-induced memory impairment in an elevated plus maze test. However, PT alone had no effect on behaviors in the open-field, hot-plate and elevated plus maze tests. We investigated the effects of PT on naloxone-induced jumping (as withdrawal sign) in morphine-dependent mice. To induce dependence, mice were twice daily treated with morphine (10-45 mg/kg, s.c.) for 5 days. Co-administrations of PT (10, 100 and 300 mg/kg, p.o.) during repeated morphine treatments significantly suppressed the naloxone (10 mg/kg, i.p.)-induced jumping. However, the naloxone-induced jumping was not affected by a single large administration of PT on the 5th day. The inhibitory effect of PT on the naloxone-induced jumping was due to the development of dependence rather than expression of withdrawal sign. Moreover, single administration of PT (30 mg/kg, p.o.) decreased the morphine levels in plasma. These results indicate that PT may be useful in facilitating narcotic detoxification.

Characterization of Anti-neurodegenerative Effects of Polygala tenuifolia in A.BETA.(25-35)-Treated Cortical Neurons

Although Polygala tenuifolia WILLD (PT) was classically mentioned as an anti-dementia drug in Chinese and Japanese traditional medicine, basic research showed only enhancement of the cholinergic function. In Alzheimer's disease, neuritic atrophy and synaptic loss occur prior to neuronal death event, and may be the first trigger of the memory impairment. Therefore, we studied effects of Polygala tenuifolia WILLD (PT) on Abeta(25-35)-induced neuronal damage using rat cortical neurons for characterization of activities of PT under Abeta-induced neuronal damage. Treatment with the water extract of PT enhanced axonal length dose-dependently after Abeta(25-35)-induced axonal atrophy. However, dendritic atrophy and synaptic loss induced by Abeta(25-35) were not recovered by treatment with PT extract. In contrast, Abeta(25-35)-induced cell damage was completely inhibited by PT extract. By characterization of PT effects on neuronal morphological plasticity and cell damage, usefulness as well as an insufficiency of PT as an anti-dementia drug was clarified.

Xanthones from the roots of Polygala caudata and their antioxidation and vasodilatation activities in vitro

Three new xanthones, 2-hydroxy-1,6,7-trimethoxyxanthone (1), 1,4-dimethoxy-2,3-methylenedioxyxanthone (2), and 7-hydroxy-1,2-dimethoxyxanthone (3), together with five known compounds, 2,7-dihydroxy-1-methoxyxanthone (4), 1-methoxy-2,3-methylenedioxyxanthone (5), 7-hydroxy-1-methoxyxanthone (6), euxanthone (1,7-dihydroxyxanthone) (7), and gentitein (1,3,7-trihydroxyxanthone) (8), were isolated from the roots of Polygala caudata. Their structures were established on the basis of spectral evidence. In the antioxidation activity screening in vitro with luminol chemiluminescence methods, compounds 1 - 5 and 7 and 8 showed H2O2 scavenger activity, with a scavenging effect of 58.4 - 94.5% at 10 microg/mL, and 26.0 - 84.7% at 2 microg/mL. Compounds 4 and 8 also exhibited scavenging effects on the reactive oxygen free radicals produced by macrophage respiratory bursts, with a scavenging effect of 71.7% and 63.4% at 10 microg/mL, 41.2% and 47.8% at 2 microg/mL, respectively. In the vasodilatation assay, compounds 4 - 7 exhibited relaxing activity on the contractions evoked by KCl in Wistar rat thoracic aorta rings in a dose-dependent manner.

Effect of Polygala tenuifolia root on behavioral disorders by lesioning nucleus basalis magnocellularis in rat

We investigated whether an aqueous extract of Polygala tenuifolia Willd (PTW) could improve the rats' memory and behavioral disorders produced by lesioning nucleus basalis magnocellularis (NBM) in rats. The animals were divided into four groups for surgery, and following that they were orally administered PTW extract for 7 and 21 days. Each group consisted of eight male Sprague-Dawley rats and were treated as follows:

CONTROL

no surgery (n = 8), PBS: 1M (mol/L) phosphate buffered saline (n = 8), IBO: 0.12 M (n = 8), QUIS: 0.12 M (n = 8). Two 0.5 microL injections were made in the vicinity of the bilateral side of the nucleus basalis magnocellularis (NBM). All rats were tested in the neurological tests and the step-through passive avoidance memory test during pre-surgery, surgery and post-surgery drug treatment. The results suggest that PTW extract has some repairing effects on the memory and behavioral disorders produced by lesioning of the NBM in rats.

and Their Antioxidant Activity

Members of Polygalaceae are known to contain a variety of different polyphenolic compounds such as xanthones, flavonoids, and biphenyl derivatives. Here, we report the isolation and structural characterization of two new phenol derivatives, named alpestrin (= 3,3',5'-trimethoxy[1,1'-biphenyl]-4-ol; 10) and alpestriose A (= 6-O-benzoyl-1-O-{6-O-acetyl-3-O-[(4-hydroxy-3,5-dimethoxyphenyl)prop-2-enoyl]-beta-D-fructofuranosyl}-alpha-D-glucopyranoside; 11), and of four known compounds (12-15) from the MeOH extract of Polygala alpestris. The relative in vitro antioxidant activities of these compounds, in comparison with other phenolic substances from Polygala vulgaris, were evaluated by means of the Briggs-Rauscher (BR) oscillating reaction, a method based on the inhibitory effects of antioxidant free-radical scavengers. The experimental antioxidant-activity values (relative to resorcinol as a standard) were compared with those calculated on the basis of the bond-dissociation enthalpies. The structure/activity relationships for the compounds examined are also discussed.

Cognitive Improving and Cerebral Protective Effects of Acylated Oligosaccharides in Polygala tenuifolia

We studied the cognitive improving and cerebral protective constituents in the roots of Polygala tenuifolia Willdenow, a well-known Chinese traditional medicine prescribed for amnesia, neurasthenia, palpitation, noctural emission and insomnia. Tenuifoliside B (1), which is one of the acylated oligosaccharides in the roots of P. tenuifolia, showed the cerebral protective effect on potassium cyanide (KCN)-induced anoxia in mice, widely used as an animal model for cerebrovascular disease, and also had an ameliorative effect on the scopolamine-induced impairment of performance in passive avoidance task in rats. Compound 1 significantly enhanced oxotremorine-induced tremors in mice, suggesting that it ameliorated the scopolamine-induced impairment of passive avoidance response by enhancing the cholinergic system. These findings show that compound 1 has cognitive improving and cerebral protective effects.

Tenuifoliose Q, a new oligosaccharide ester from the root of Polygala tenuifolia Willd

From the cortexes of Polygala tenuifolia Willd., a new oligosaccharide ester, tenuifoliose Q (1), was isolated together with three known compounds. The structure of 1 was elucidated by spectroscopic and physiochemical analysis as an oligosaccharide esterified with acetic, benzoic and p-hydroxycinnamoyl acid.

Induction of NGF synthesis in astrocytes by onjisaponins of Polygala tenuifolia, constituents of kampo (Japanese herbal) medicine, Ninjin-yoei-to

The effect of a kampo medicine, Ninjin-yoei-to (NYT; Ren-shen-yang-rong-tang in Chinese) on nerve growth factor (NGF) secretion from the cultured rat astrocytes was examined in vitro. When rat embryo astrocytes were cultured in the presence of NYT for 24 h, the amount of NGF in the medium was significantly increased in a dose dependent manner. Among 14 kinds of component herbs in NYT, the roots of Polygala tenuifolia and roots of Panax ginseng extracts increased NGF levels from the astrocytes. Saponin fraction from the roots of P. tenuifolia enhanced the production of NGF, however phenolic glycoside fraction showed no effect. Onjisaponins A, B, E, F and G as major saponins of the root of P. tenuifolia strongly increased the NGF level, whereas ginsenosides Rb1 and Rg1 did not affect the NGF level. Onjisaponin F also induced ChAT mRNA level in rat basal forebrain cells. These results indicate the possibility that NYT and/or onjisaponins in P. tenuifolia may have potential therapeutic effects for the treatment of Alzheimer disease patients.

Ninjin-yoei-to (Ren-Shen-Yang-Rong-Tang) and Polygalae radix improves scopolamine-induced impairment of passive avoidance response in mice

We investigated the effect of Ninjin-yoei-to (Ren-Shen-Yang-Rong-Tang), a Japanese herbal medicine, and found that 1000 mg/kg p.o. improved the scopolamine-induced impairment of passive avoidance response in mice. Further, the same dose of Ninjin-yoei-to enhanced oxotremorine-induced tremors in mice. The water extract of Polygalae radix, one of the constituent herbs of Ninjin-yoei-to, at a dose of 100 mg/kg significantly improved the scopolamine-induced impairment of passive avoidance response and enhanced oxotremorine-induced tremors in mice. Moreover, the enhancement of oxotremorine-induced tremors by Ninjin-yoei-to (1000 mg/kg) and Polygalae radix (100 mg/kg) was completely antagonized by pretreatment of scopolamine hydrobromide (0.5 mg/kg). These results suggest that Ninjin-yoei-to may improve the scopolamine-induced impairment of passive avoidance response by enhancing the cholinergic system and that Polygalae radix may be involved in the action of Ninjin-yoei-to.

Behavioural pharmacology of polygalasaponins indicates potential antipsychotic efficacy

Polygalasaponins were extracted from a plant (Polygala tenuifolia Willdenow) that has been prescribed for hundreds of years to treat psychotic illnesses in Korean traditional medicine. Previous in vitro binding studies suggested a potential mechanism for its antipsychotic action, as polygalasaponin was shown to have an affinity for both dopamine and serotonin receptors [Psychopharmacol. Bull. 31 (1995) 139.]. In the present study we have investigated the functional in vivo actions of this material in tests that are predictive of dopamine and serotonin antagonist activities. Polygalasaponin (25-500 mg/kg) was shown to produce a dose-related reduction in the apomorphine-induced climbing behaviour (minimum effective dose [ED(min)] 25 mg/kg ip, 250 mg/kg sc and po), the 5-hydroxytryptamine (5-HTP)-induced serotonin syndrome (ED(min) 50 mg/kg ip) and the MK-801-induced hyperactivity (ED(min) 25 mg/kg ip) in mice. This compound also reduced the cocaine-induced hyperactivity (ED(min) 25 mg/kg ip) in rats. These results demonstrated that polygalasaponin has dopamine and serotonin receptor antagonist properties in vivo. This might suggest its possible utility as an antipsychotic agent.

Hypotensive effect of tenuifolic saponin and its mechanism

AIM

To study the effect of tenuifolic saponin (TS) on arterial pressure.

METHODS

Mean arterial pressure (MAP) was recorded from left carotid artery in rat which was anesthetized with urethane and then injected i.v. gtt with a transfusion of NaCl 0.15 mol.L-1. Systolic blood pressure (SBP) of conscious rat and renovascular hypertensive rat (RVHR) was measured by tail cuff method.

RESULTS

TS 2, 4, 8 mg.kg-1 i.v., 20 and 40 mg.kg-1 i.g. reduced the MAP by 31%, 37%, 50%, 21%, and 31%, respectively. Bilateral vagotomy plus atropine (Atr) i.v., or pretreatment with diphenhydramine hydrochloride (Dip) failed to influence TS effect. Lack of effect of TS on carotid-occlusion-induced- or epinephrine (Epi)-induced-hypertensive response was found. SBP in conscious rat and RVHR was suppressed, highest by 38.0% and 26.8% at 60 and 90 min, maintaining at least 2 and 3 h, respectively, after i.g. TS 40 mg.kg-1.

CONCLUSION

TS reduced the arterial pressure, not related to vagus excitation, ganglionic blockade, and peripheral alpha-adrenergic-, M-cholinergic-, and H1-receptors.