[Studies on the constituents of the useful plants. VIII. The constituents of Lespedeza cuneata G. Don (author's transl)]

Effect of oral gargle containing Lespedeza cuneata extract on periodontal health improvement and disease prevention: a randomized, controlled clinical trial

BACKGROUND

This study aimed to evaluate the antiplaque and antibacterial effects of a mouthwash containing Lespedeza cuneata (LC) extract through clinical periodontal disease (PD) indicators and changes in PD-causing bacteria.

METHODS

A total of 63 subjects participated in this double-blind clinical trial. Subjects were divided into two groups: 32 participants gargled with LC extract, and 31 used saline. Scaling was performed 1 week before the experiment to secure the homogeneity of the subjects' oral conditions. After gargling with 15 ml of each solution for 1 min, participants spit out the solution to remove any residual mouthwash solution. Then, PD-related bacteria were measured via the O'Leary index, plaque index (PI), and gingival index (GI). The clinical data were collected three times: before gargling, immediately after gargling, and 5 d after gargling.

RESULTS

After 5 d, the O'Leary index, PI, and GI scores were significantly reduced in the LC extract gargle group (p < 0.05). PD-inducing Gram-positive and -negative bacteria were also reduced, confirming the LC extract's effect on periodontal health improvement and disease prevention.

CONCLUSION

Mouthwash containing LC extract, a new alternative natural substance that is safe and effective, may be used to treat PD because of its ability to inhibit and prevent PD.

Phytochemical Constituents Identified from the Aerial Parts of Lespedeza cuneata and Their Effects on Lipid Metabolism during Adipocyte Maturation

Lespedeza cuneata, belonging to Fabaceae, is well-known as Chinese bushclover, and it has been used in traditional folk medicines for the treatment of disorders, such as diabetes, hematuria, and insomnia. As part of continuing research projects to discover interesting natural compounds with biological activities from Korean medicinal plants, the phytochemical investigation of L. cuneata resulted in the isolation of five chemical constituents: α-tocopherol (1), 7a-methoxy-α-tocopherol (2), 13(R)-hydroxy-octadeca-(9Z,11E,15Z)-trien-oic acid (3), α-dimorphecolic acid (4), and lupeol (5). The structural determination of the isolated compounds was elucidated from data gathered through nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography–mass spectrometry (LC/MS). Until now, this study is the first to report these five compounds from the plant L. cuneata. Moreover, these isolated compounds (1–5) were evaluated for their anti-adipogenesis effects and their role in lipid metabolism during adipocyte maturation. As a result, the upregulation of mRNA expression levels of Fabp4 from 3T3-L1 pre-adipocytes treated with compounds 3 and 4 demonstrated that these compounds efficiently induced adipocyte differentiation. Furthermore, compounds 3 and 4 were found to regulate lipid metabolism by the induction of lipolytic and of lipogenic gene expressions. Therefore, experimental data from these findings supported that the compounds 3 and 4 induce the adipogenesis of 3T3-L1 pre-adipocytes and regulate lipid metabolism.

Determination of Afzelin and Astragalin from Lespedeza cuneata on Aldose Reductase Inhibition

The bioactive chemicals in L. cuneata were investigated by repeated column chromatography and their effect on aldose reductase (AR), obtained from rat lenses, was examined. Results showed that the ethyl acetate and n-butanol fractions of L. cuneata exhibited potential inhibitory effect against AR with IC50 values of 0.57 and 0.49 μg/mL, respectively. Phytochemical analysis of these two fractions resulted in the isolation of five flavonoids namely, acacetin (1), afzelin (2), astragalin (3), kaempferol (4) and scutellarein 7-O-glucoside (5). The AR inhibitory effect of compounds 1-5 was explored; compounds 2, 3 and 5 showed potential AR-inhibitory effects with IC50 values of 2.20, 1.91 and 12.87 μM, respectively. Quantitative analysis of afzelin (2) and astragalin (3) in L. cuneata by high performance liquid chromatography with ultraviolet detection revealed its content to be 0.722-11.828 and 2.054-7.006 mg/g, respectively. Overall, this study showed that L. cuneata is rich in flavonoids with promising AR-inhibitory activities, which can be utilized for the development of natural therapies for treating and managing diabetic complications.

Aviculin Isolated from Lespedeza cuneata Induce Apoptosis in Breast Cancer Cells through Mitochondria-Mediated Caspase Activation Pathway

The global incidence of breast cancer has increased. However, there are many impediments to the development of safe and effective anticancer drugs. The aim of the present study was to evaluate the effect of aviculin isolated from Lespedeza cuneata (Dum. Cours.) G. Don. (Fabaceae) on MCF-7 human breast cancer cells and determine the underlying mechanism. Using the bioassay-guided isolation by water soluble tetrazolium salt (WST-1)-based Ez-Cytox assay, nine compounds (four lignan glycosides (1-4), three flavonoid glycosides (5-7), and two phenolic compounds (8 and 9)) were isolated from the ethyl acetate (EA) fraction of the L. cuneata methanolic extract. Of these, aviculin (2), a lignan glycoside, was the only compound that reduced metabolic activity on MCF-7 cells below 50% (IC₅₀: 75.47 ± 2.23 μM). The underlying mechanism was analyzed using the annexin V Alexa Fluor 488 binding assay and Western blotting. Aviculin (2) was found to induce apoptotic cell death through the intrinsic apoptosis pathway, as indicated by the increased expression of initiator caspase-9, executioner caspase-7, and poly (ADP-ribose) polymerase (PARP). Aviculin (2)-induced apoptotic cell death was accompanied by an increase in the Bax/Bcl-2 ratio. These findings demonstrated that aviculin (2) could induce breast cancer cell apoptosis through the intrinsic apoptosis pathway, and it can therefore be considered an excellent candidate for herbal treatment of breast cancer.

Effects of Lespedeza Cuneata aqueous extract on testosterone-induced prostatic hyperplasia

CONTEXT

Lespedeza cuneata G. Don (Fabaceae), has been used as a traditional treatment of various diseases. There is a report L. cuneata effects on hormone replacement therapy for endocrine-related disease. However, studies related to benign prostatic hyperplasia (BPH) have not been investigated.

OBJECTIVE

The effects of L. cuneata aqueous extract (LCW) on testosterone-induced prostatic hyperplasia (TPH) were examined.

MATERIALS AND METHODS

Male Wistar rats (10 weeks, 330-350 g) were randomly divided to 6 groups (n = 6): Control group; TPH group (3 mg/kg, s.c, daily); TPH + LCW (25, 50, 100 mg/kg); TPH + Finasteride 10 mg/kg for 6 weeks. At the end of treatment, histological change of prostate, serum dihydrotestosterone (DHT) level, mRNA expression of 5α-reductase, inflammatory factors, proliferating cell nuclear antigen (PCNA) and fibroblast growth factor-2 (FGF-2) in prostate were examined. Then, LCW was treated with BPH-1, a human BPH cell line, at 25, 50, 100 μg/mL for 24 h and examine mRNA level of androgen receptor (AR) and prostate-specific antigen (PSA). In addition, the content of vicenin-2 was analyzed.

RESULTS

LCW treatment of TPH inhibited serum DHT levels by 54.5, 51.2 and 54.1% and mRNA expression of 5α-reductase were inhibited 54.3, 61.3 and 73.6%, respectively. In addition, mRNA expression of inflammatory factors, PCNA and FGF-2 were decreased in the prostate of rats. Also, LCW attenuated mRNA level of AR and PSA in BPH-1 cell. The content of vicenin-2 in the LCW was analyzed to 0.89 mg/g.

DISCUSSION AND CONCLUSIONS

Based on the results, LCW is a potential pharmacological candidate for the treatment of prostatic hyperplasia.

Antiwrinkle and antimelanogenesis activity of the ethanol extracts of Lespedeza cuneata G. Don for development of the cosmeceutical ingredients

To develop the ingredient with the cosmeceutical function, the antiwrinkle and antimelanogenesis effects of the ethanol extract of Lespedeza cuneata G. Don were investigated. DPPH radical scavenging activity was significantly increased with the extract of L. cuneata G. Don. Cell viability on CCD986Sk human fibroblast was also increased by the ethanol extract of L. cuneata G. Don. The inhibitory function of the extract of L. cuneata G. Don on collagenase, elastase, and tyrosinase was evaluated. Protein expression level of Claudin-1, Occludin, and ZO-1 was up-regulated in HaCaT human keratinocyte by the extract of L. cuneata G. Don. In addition, the extract of L. cuneata G. Don inhibited melanin synthesis in B16F10 murine melanoma cells by decreasing MITF, TRP1, and TRP2 protein levels and increasing the phosphorylated Erk and Akt. Thus, these findings would be useful for developing the new cosmeceutical formulations based on the extract of L. cuneata G. Don.

Protective effect of Lespedeza cuneata ethanol extract on Bisphenol A-induced testicular dysfunction in vivo and in vitro

PURPOSE

Bisphenol A (BPA) has been regarded as a possible risk factor for reproductive health. We examined potential reproductive health benefits of Lespedeza cuneata ethanol extract (LCE). Previously, Lespedeza cuneata showed many therapeutic effects. However, the protective effect of LCE on BPA-induced testicular dysfunction and its mechanisms have not been precisely studied.

METHODS

Mice were randomly divided into six groups (n = 7). Sperm counts and motility were measured by light microscope. Testosterone, total cholesterol, triglycerides, HDL, LDL-cholesterol, glucose, free fatty acids, hs-CRP, Angiotensinogen, Angiotensin II, GOT, GPT, TBARS, GSH, CAT, and SOD1 were measured in mouse serum. The potential protective effects of the LCE on mouse sertoli cells were evaluated.

RESULTS

Oral administration of LCE in BPA-exposed male mice restored testis weight, sperm count, motility, and testosterone levels by inhibiting markers in serum. In addition, treatment with LCE in BPA-treated TM4 sertoli cells recovered cell viability by attenuating Bax expression and activating caspase 3 and PARP.

CONCLUSIONS

These results indicate that LCE prevented BPA-induced testicular dysfunction and cell viability in BPA-treated TM4 sertoli cells. Our study also suggests that LCE has the potential to protect male reproductive health.

Three new lignanosides from the aerial parts of Lespedeza cuneata

Three new lignanosides (+)-(8S,7'S,8'S)-burselignan-9'-O-β-d-glucopyrano side (1), (+)-(8R,7'S,8'R)-isolariciresinol-9'-O-β-d-fucopyranoside (2), (-)-(8S, 7'R,8'R)-methoxyisoariciresinol-9'-O-α-l-rhamnoside (3), along with four known compounds, were isolated from the aerial parts of Lespedeza cuneata (Dum.Cours.) G.Don. The fucopyranoside has not been reported in this genus previously. Their structures and absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses (UV, IR, HR-ESI-MS, 1D and 2D NMR, CD), as well as by comparison with known analogues in the literature. Compounds 2 and 6 showed moderate hepatoprotective activities.

Flavonoids isolated from Lespedeza cuneata G. Don and their inhibitory effects on nitric oxide production in lipopolysaccharide-stimulated BV-2 microglia cells

BACKGROUND

Lespedeza cuneata (Dum. Cours.) G. Don, a perennial legume native to Eastern Asia, has been used therapeutically in traditional Asian medicine to protect the function of liver, kidneys and lungs. However, its effect on inflammatory nitric oxide (NO) production and the active constituents have not yet been explored.

OBJECTIVE

In this study, we investigated the phytochemical constituents of L. cuneata and evaluated their effect on NO production using lipopolysaccharide (LPS)-stimulated BV2 cells.

MATERIALS AND METHODS

The 80% methanol extract of the aerial part of L. cuneata were used for the isolation of flavonoids. The isolated compounds were elucidated by various spectroscopic methods including nuclear magnetic resonance and mass spectrometry spectrometry. To evaluate the effect on inflammatory NO production, LPS-stimulated murine microglia BV-2 cells were used as a screening system.

RESULTS

Nine flavonoids were isolated from the aerial parts of L. cuneata. Among the isolated flavonoids, compounds 4, 5, 7 and 9 are reported from the genus Lespedeza for the first time. Moreover, compounds 1 and 6 showed significant inhibitory effects on NO production in LPS-stimulated BV2 cells without cell toxicity.

CONCLUSION

In this study, nine flavonoids were isolated from L. cuneata. Among the compounds, only 1 and 6, which have free hydroxyl groups at both C3 and C7 showed significant inhibitory activity on NO production in LPS-stimulated BV2 cells. These results suggested L. cuneata and its flavonoid constituents as possible candidate for the treatment of various inflammatory diseases.

Hepatoprotective effect of flavonoid glycosides from Lespedeza cuneata against oxidative stress induced by tert-butyl hyperoxide

The aerial parts of Lespedeza cuneata G. Don, perennial legume native to Eastern Asia, have been used therapeutically in traditional Asian medicine to protect the function of liver, kidneys and lungs. However, little is known about the pharmaceutical effect of extracts from this plant. In the present study, the aerial parts of L. cuneata were used to prepare an ethanol extract, which was then tested for hepatoprotective effects against injury by tert-butyl hyperoxide (t-BHP). At a dose of 20 μg/mL, the ethanol extract significantly protected HepG2 cells against the cytotoxicity of t-BHP. Further fractionation of the extract with ethyl acetate allowed the isolation of five flavonoid compounds that were structurally identified by ¹H and ¹³C NMR spectroscopy as isovitexin, hirsutrin, trifolin, avicularin and quercetin. Hirsutrin, avicularin and quercetin (10 μM) showed clear hepatoprotective activity against injury by t-BHP in HepG2 cells, whereas isovitexin and trifolin showed no protective effects. The observed hepatoprotective effect of the investigated compounds showed a high correlation with radical scavenging activity, which followed the structure-activity relationships of the flavonoid aglycones.