Vascular relaxation induced by aqueous extract of Lespedeza cuneata via the NO-cGMP pathway

Therapeutic Potential of Lespedeza bicolor to Prevent Methylglyoxal-Induced Glucotoxicity in Familiar Diabetic Nephropathy

Lespedeza bicolor (LB) is often used in traditional medicine to remove toxins, replenish energy stores, and regulate various symptoms of diabetes. This study aimed to explore the use of LB as a therapeutic to prevent diabetic nephropathy in methylglyoxal (MGO)-treated models in vitro and in vivo. Western blotting, immunostaining, and biochemical assays were used to obtain several experimental readouts in renal epithelial cells (LLC-PK1) and BALB/c mice. These include: production of reactive oxygen species (ROS), formation of advanced glycation end-products (AGEs), expression of receptor for advanced glycation end-products (RAGE), apoptotic cell death, glucose levels, fatty acid and triglyceride levels, expression of pro-inflammatory cytokines IL-1β and TNF-α, glyoxalase 1 (Glo1), and nuclear factor erythroid 2-related factor 2 (Nrf2). Pretreatment with LB significantly reduced MGO-induced cellular apoptosis, intracellular production of ROS, and formation of AGEs to ameliorate renal dysfunction in vitro and in vivo. Interestingly, administering LB in MGO-treated cells and mice upregulated the expression of Nrf2 and Glo1, and downregulated the expression of IL-1β and TNF-α. Moreover, LB reduced MGO-induced AGE accumulation and RAGE expression in the kidneys, which subsequently reduced AGE-RAGE interactions. Overall, LB ameliorates renal cell apoptosis and corrects renal dysfunction in MGO-treated mice. These findings extend our understanding of the pathogenic mechanism of MGO-induced nephrotoxicity and regulation of the AGE/RAGE axis by Lespedeza bicolor.

Aqueous extract of Lespedeza cuneata improves male menopause by increase of nitric oxide and dihydrotestosterone

This study aimed to evaluate the effect of aqueous extract of Lespedeza cuneata (ALC) on men menopause induced erectile dysfunction (ED) and testosterone deficiency syndrome (TDS) in vitro and in vivo. Nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) have been fundamental factors of ED, and free testosterone such as dihydrotestosterone (DHT) has a crucial role in mitigation of TDS. ALC increased the production of NO in a dose-dependent manner in vitro and in vivo. The level of neuronal nitric oxide synthase and cGMP was increased in the ALC group. The level of DHT and 17-beta hydroxysteroid dehydrogenases (17β-HSD) was also increased in the ALC group. There was no significant change of hepatotoxicity, renal toxicity, lipid metabolism, and glucose. These results suggest that ALC enhanced NO, cGMP and free testosterone which could be developed as a health supplement for improving male menopause.

Lespedeza cuneata protects the endothelial dysfunction via eNOS phosphorylation of PI3K/Akt signaling pathway in HUVECs

BACKGROUND

Lespedeza cuneata G.Don (LCE), which belongs to the genus Lespedeza (Leguminosae), is a traditional oriental medicine known to prevent diabetes and cardiovascular diseases. However, no scientific studies about the effectiveness of LCE, their responsible bioactive constituents, and its mechanisms against endothelial dysfunction have been performed.

PURPOSE

This study was performed to investigate the role of LCE and its chemical components in ameliorating endothelial dysfunction.

METHODS

The production of nitric oxide (NO) was evaluated after LCE treatment in HUVECs. Cell viability was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reagent. Western blot analysis was performed to determine the protein expression of endothelial nitric oxide synthase (eNOS) and protein kinase B (PKB, also known as Akt) in human umbilical vein endothelial cells (HUVECs).

RESULTS

Pretreatment with L-NAME and LY294002 significantly decreased the LCE-induced NO production, as well as eNOS and Akt phosphorylation. β-Sitosterol and β-Sitosterol 6'-linolenoyl-3-O-β-D-glucopyranoside are the bioactive constituents increase NO production as well as eNOS phosphorylation.

CONCLUSION

Our findings suggest that LCE increase NO production via eNOS phosphorylation of PI3K/Akt signaling pathway.

Efficacy and Safety of a Mixed Extract of Trigonella foenum-graecum Seed and Lespedeza cuneata in the Treatment of Testosterone Deficiency Syndrome: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Purpose

The aim of this study was to investigate the efficacy and safety of a mixed extract of Trigonella foenum-graecum seed and Lespedeza cuneata (TFGL) for the treatment of testosterone deficiency syndrome (TDS).

Materials and Methods

Patients were instructed to take a placebo or 200 mg TFGL capsule twice per day for 8 weeks. The primary efficacy variable was the change from baseline in the Aging Males' Symptoms scale (AMS), as well as levels of serum total and free testosterone. Secondary efficacy measurements included changes from baseline in the number of ‘yes’ answers on the Androgen Deficiency in the Aging Male (ADAM) questionnaire, levels of serum total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglyceride, all domain scores of the International Index of Erectile Function (IIEF), perceived stress scale-10 (PSS-10), as well as changes in body composition.

Results

The TFGL group exhibited a significant improvement in the AMS scores at 8 weeks, total testosterone at 8 weeks, and free testosterone at 4 and 8 weeks. At 4 weeks, 25% of the TFGL group changed to negative in terms of ADAM scores and 34.1% of the TFGL group had negative scores at the end of the study. The TFGL group exhibited a significant improvement in total cholesterol, HDL-C, LDL-C, triglyceride, IIEF scores, and PSS-10 scores at 8 weeks.

Conclusions

The mixed extract of TFGL resulted in significant improvements in symptoms of TDS, as measured by the AMS, ADAM, PSS-10 and testosterone levels.

Ultrasonicated Lespedeza cuneata extract prevents TNF-α-induced early atherosclerosis in vitro and in vivo

This study evaluated the use of ultrasonication to extract Lespedeza cuneata as a potential nutraceutical for preventing vascular inflammation.

Lespedeza bicolor ameliorates endothelial dysfunction induced by methylglyoxal glucotoxicity

BACKGROUND

Lespedeza species have been used as a traditional medicine to treat nephritis, azotemia, inflammation, energy depletion, diabetes, and diuresis.

PURPOSE

The purpose of this study is to screen the most potent Lespedeza species against methylglyoxal (MGO)-induced glucotoxicity, and to elucidate the mechanisms of action. Also, we will attempt to identify small chemical metabolites that might be responsible for such anti-glucotoxicity effects.

METHODS

Firstly, the protective effect of 26 different Lespedeza species against MGO-induced toxicity in human umbilical vein endothelial cells was investigated. The chemical metabolites of the most potent species (Lespedeza bicolor 1 (LB1) were identified by high pressure liquid chromatography quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS/MS), then quantified by HPLC. The effects of LB1 on MGO-induced apoptosis were measured by annexin V-FITC staining and western blot. Inhibitory effects of LB1 on MGO-induced ROS generation, and effect of LB1 on advanced glycation end products (AGEs) inhibitor or a glycated cross-link breaker are also measured.

RESULTS

Among different Lespedeza species, LB1 extract was shown to reduce intracellular reactive oxidative species, exhibit anti-apoptotic effects, strongly inhibit all the mitogen-activated protein kinase signals, inhibit MGO-induced AGEs formation, and break down preformed AGEs. We tentatively identified 17 chemical constituents of LB1 by HPLC-Q-TOF-MS/MS. Among those, some components, such as genistein and quercetin, significantly reduced the AGEs formation and increased the AGEs-breaking activity, resulting in the reduction of glucotoxicity.

CONCLUSION

LB1 extract has shown to be effective in preventing or treating MGO-induced endothelial dysfunction.

A potential anti-inflammation activity and depigmentation effect of Lespedeza bicolor extract and its fractions

Postinflammatory hyperpigmentation (PIH) is an acquire hypermelanosis after cutaneous inflammation and injury. The aim of the present study was to investigate a natural ingredient with the anti-inflammatory and depigmentation activities into possible applications of postinflammatory hyperpigmentation. Methanol extracts of Lespedeza bicolor and its various fractions inhibited LPS-induced NO production in RAW 264.7 macrophages in a concentration-dependent manner. In particular, the ethyl acetate fraction was shown to be inhibition of NO production (89%) and down-regulation of iNOS mRNA without causing cytotoxicity. In addition, ethyl acetate fraction significantly attenuated LPS-induced NF-κB activation (P < 0.05), indicating the anti-inflammatory activity due to NF-κB inhibition. Moreover, extracts, mainly ethyl acetate fraction, exhibited not only DPPH free radical scavenging activity (IC₅₀, 112.45 μg/mL) with 4 times lower activity than ascorbic acid, but also anti-tyrosinase activity (IC₅₀, 1 μg/mL) with a similar activity to arbutin showing a competitive inhibitor. Furthermore, vitexin and haginins A, B and C were identified through LC–MS analysis as potential compounds responsible for these effects. These results suggest that L. bicolor extract have anti-inflammatory, antioxidant activities and tyrosinase inhibitory effect and it might be used in the management of postinflammatory pigmentation through inhibition of pathogenic process involved in hyperpigmentation.