Protective effects of corni fructus extract in mice with potassium oxonate-induced hyperuricemia.

Corni fructus is consumed as food and herbal medicine in Chinese culture. Studies have revealed that corni fructus exhibits potent antioxidant activity; however, few studies have investigated the ability of corni fructus to lower uric acid concentrations. In this study, the xanthine oxidase (XO) inhibition and uric acid-lowering effect of corni fructus extract (CFE) were evaluated in mice with potassium oxonate-induced hyperuricemia. Hyperuricemia is a chronic disease prevalent worldwide and is associated with high recurrence rates. In addition, drugs used to treat hyperuricemia induce side effects that discourage patient compliance. Hyperuricemia induces metabolic imbalances resulting in accumulative uric acid deposition in the joints and soft tissues. Hyperuricemia not only induces gout but also interrupts hepatic and renal function, thereby trigging severe inflammation and various complications, including obesity, nonalcoholic fatty liver disease, diabetes, and metabolic diseases. In this study, the ethyl acetate fraction (EAF) of CFE resulted in yields of antioxidant photochemical components significantly higher than those of CFEs formed using other substances. The EAF of CFE exhibited high free radical scavenging activity and XO inhibition and effectively lowered uric acid concentrations in the animal model of chemically induced hyperuricemia. The results of this study can serve as a reference for the prevention of preclinical gout as well as for functional food research.

Far-Infrared Therapy Improves Arteriovenous Fistula Patency and Decreases Plasma Asymmetric Dimethylarginine in Patients with Advanced Diabetic Kidney Disease: A Prospective Randomized Controlled Trial.

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase and plays a significant role in the pathogenesis of arteriovenous fistula (AVF) dysfunction. The aim of this study is to evaluate the effect of far-infrared (FIR) therapy on the maturation and patency of newly-created AVFs in patients with advanced diabetic kidney disease (DKD) as well as the concurrent change in plasma ADMA. The study enrolled 144 participants with advanced DKD where 101 patients were randomly allocated to the FIR therapy group (N = 50) and control group (N = 51). Patients receiving FIR therapy had a decreased AVF failure rate within 12 months (16% versus 35.3%; p = 0.027); decreased incremental change of ADMA concentration at the 3rd and 12th month; increased AVF blood flow at the 1st, 3rd, and 12th month; increased 3-month physiologic maturation rate (88% versus 68.6%; p = 0.034); increased 1-year unassisted AVF patency rate (84% versus 64.7%; p = 0.017); and increased clinical AVF maturation rate within 12 months (84% versus 62.7%; p = 0.029) compared to the control group. The study demonstrates that FIR therapy can reduce the incremental changes in plasma ADMA concentration, which may be associated with the improvement of AVF prognosis in patients with advanced DKD.

Effect of Quercetin on Injury to Indomethacin-Treated Human Embryonic Kidney 293 Cells.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are used to treat inflammation and pain and even to prevent the progression of cardiovascular disease. They have become widely used because of their effectiveness, especially among athletes performing high-intensity training. Indomethacin is used for pain management in sports medicine and is highly effective and versatile. However, several clinical studies have reported that indomethacin induces acute renal damage. In the present study, we determined that indomethacin reduced human embryonic kidney 293 (HEK293) cell viability in a concentration-dependent manner by triggering apoptosis. In addition, we demonstrated the effect of quercetin on indomethacin-treated HEK293 cells by inactivating the caspase-3 and caspase-9 signals. Furthermore, quercetin reduced ROS production and increased mitochondrial membrane potential (ΔΨm) in indomethacin-treated HEK293 cells. Our results indicate that quercetin can interrupt the activated caspase and mitochondrial pathway induced by indomethacin in HEK293 cells and affect apoptotic mRNA expression. Quercetin can protect against indomethacin-induced HEK293 cell apoptosis by regulating abnormal ΔΨm and apoptotic mRNA expression.

Long-term prognosis of vascular access in hemodialysis patients with systemic lupus erythematosus: a retrospective cohort study.

Patients with systemic lupus erythematosus (SLE) have a higher risk of vascular complications. This retrospective cohort study aimed to analyze the differences in the risk of arteriovenous fistula or graft (AVF/AVG) dysfunction in hemodialysis patients with and without SLE from Taiwan's National Health Insurance Database over a 10-year period. AVF/AVG dysfunction is defined as the occurrence of the first episode of intervention after vascular access creation. A total of 1366 HD patients with SLE had higher incidence rates of AVF/AVG dysfunction than 4098 non-SLE HD patients in the following 4 periods: (1) after 1 year (incidence rates = 15.21% and 13.01%, respectively; subdistribution hazard ratio (SHR) = 1.16; P = 0.007), (2) 1st-to-10th-year period (15.36% and 13.25%; SHR = 1.16; P = 0.007), (3) 5th-to-10th-year period (11.91% and 8.1%; SHR = 1.42; P = 0.003), and (4) overall period (23.53% and 21.66%; SHR = 1.09; P = 0.027). In conclusion, there were significantly higher incidence rates of AVF/AVG dysfunction in SLE patients during the long-term follow-up period. Vascular access function should be monitored regularly by clinical examinations, especially after 1 year and during 5 to 10 years, to improve AVF/AVG patency and dialysis adequacy in SLE patients undergoing maintenance hemodialysis.

Bioactive naphthoquinones and triterpenoids from the fruiting bodies of Taiwanofungus salmoneus.

Drug resistance of cancer cells stands for the major problem of the treatment failure for chemotherapy or target therapy. Overexpression of efflux pumps leading to multidrug resistance (MDR) is still an important issue needed to be solved. In the present study, Taiwanofungus salmoneus was selected as the topic and eleven undescribed constituents including four naphthoquinones salmonones A-D (1-4) and seven triterpenoids salmoneatins A-G (5-11), along with one chromanone (12) and two benzenoids (13 and 14) reported from the natural sources for the first time, as well as twenty-one known compounds were characterized. The structures of undescribed compounds were established by the spectroscopic and spectrometric analyses. In addition, the plausible biosynthetic mechanism of purified naphthoquinones was proposed and these compounds may be the excellent chemotaxonomic markers. Moreover, the isolates were evaluated for their P-gp inhibitory effects and the results showed that most of the examined compounds were effective. Among the tested compounds, 5, 10, 2,3-dimethoxy-5-(2',5'-dimethoxy-3',4'-methylenedioxyphenyl)-7-methyl-[1,4]naphthoquinone, zhankuic acid A methyl ester, and camphoratin F can reverse the resistance of paclitaxel or vincristine with the reversal folds in the range of 51093.3 and 259.5. These experimental data would initiate the possible development of Taiwanofungus salmoneus for the cancer therapy in the future.

A Rapid and Feasible 1H-NMR Quantification Method of Ephedrine Alkaloids in Ephedra Herbal Preparations.

A highly specific and sensitive proton nuclear magnetic resonance (1H-NMR) method has been developed for the quantification of ephedrine alkaloid derivatives in Ephedra herbal commercial prescriptions. At the region of δ 4.0 to 5.0 ppm in the 1H NMR spectrum, the characteristic signals are separated well from each other, and six analogues in total, methylephedrine (ME), ephedrine (EP), norephedrine (NE), norpseudoephedrine (NP), pseudoephedrine (PE), and methylpseudoephedrine (MP) could be identified. The quantities of these compounds are calculated by the relative ratio of the integral values of the target peak for each compound to the known concentrations of the internal standard anthracene. The present method allows for a rapid and simple quantification of ephedrine alkaloid derivatives in Ephedra-related commercial prescriptions without any preliminary purification steps and standard compounds, and accordingly it can be a powerful tool to verify different Ephedra species. In comparison to conventional chromatographic methods, the advantages of this method include the fact that no standard compounds are required, the quantification can be directly performed on the crude extracts, a better selectivity for various ephedrine alkaloid derivatives, and the fact that a very significant time-gain may be achieved.

Intraocular pressure-lowering effect of Cordyceps cicadae mycelia extract in a glaucoma rat model.

Glaucoma is a leading cause of irreversible blindness worldwide. This study evaluates the reduction of intraocular pressure (IOP) induced by C. cicadae mycelia extract in a steroid-induced rat model of glaucoma. Cordyceps cicadae mycelia is a well-known and valued traditional Chinese herbal medicine. C. cicadae mycelia were cultured using a liquid fermentation technique. The harvested C. cicadae mycelia were then lyophilized and extracted with two solvents, water and ethanol. The aqueous extract (CCM-DW) and ethanolic extract (CCM-EtOH) of the mycelia were obtained through lyophilization. Sprague Dawley rats were randomly divided into four groups (n = 6 in each group): a normal group, a control group, and experimental groups treated with CCM-DW, or CCM-EtOH (both at 50 mg/kg/body weight). Except for those in the normal group, all rats received a subconjunctival injection of betamethasone to induce high IOP. The rats in the experimental groups received a daily administration of CCM by oral gavage for four consecutive weeks. IOP reduction is the known treatment for glaucoma. The results revealed that steroid treatment caused a significant increase in the animals' IOP (control group). Elevated IOP decreased significantly after treatment with CCM-DW and CCM-EtOH (p < 0.01), and CCM-DW was more effective than CCM-EtOH. CCM-DW and CCM-EtOH were capable of causing significant decreases in high IOP-induced lesions in pathological studies in which it was shown that the efficacy of CCM-DW surpassed that of CCM-EtOH. After CCM-DW administration for 28 days, there were significant decreases in malondialdehyde and lactate dehydrogenase levels and significant increases in catalase, superoxide dismutase, and glutathione peroxidase levels. In summary, C. cicadae mycelia may be beneficial for preventing or treating glaucoma due to its significant IOP-lowering and antioxidant activities.

Application of Lanthanide Shift Reagent to the 1H-NMR Assignments of Acridone Alkaloids.

This study investigates the application of the paramagnetic shift reagent tris(dipivaloylmethanato)-europium(III) in NMR spectral studies of permethoxyacridone alkaloids (1-3) and pyranoacridone alkaloids (4-6). The induced chemical shifts (∆δ) of all protons were observed for the same molecule, and were compared to deduce the positions resulting from the distance nearby the Eu(dpm)3. Assignment of the H-2, H-4 and H-8 of polysubstituted acridones could be distinguished based on the least-squares method of lanthanide-induced shifts plotted against the mole ratios of Eu(dpm)3 to the substrate. The developed method is not only potentially useful for determining the planar structures of polysubstituted compounds, such as acridones, anthraquinones, xanthones, flavonoids, and phenanthrenes, but also applicable for their stereochemistry.

Effect of Quercetin on Dexamethasone-Induced C2C12 Skeletal Muscle Cell Injury.

Glucocorticoids are widely used anti-inflammatory drugs in clinical settings. However, they can induce skeletal muscle atrophy by reducing fiber cross-sectional area and myofibrillar protein content. Studies have proven that antioxidants can improve glucocorticoid-induced skeletal muscle atrophy. Quercetin is a potent antioxidant flavonoid widely distributed in fruits and vegetables and has shown protective effects against dexamethasone-induced skeletal muscle atrophy. In this study, we demonstrated that dexamethasone significantly inhibited cell growth and induced cell apoptosis by stimulating hydroxyl free radical production in C2C12 skeletal muscle cells. Our results evidenced that quercetin increased C2C12 skeletal cell viability and exerted antiapoptotic effects on dexamethasone-treated C2C12 cells by regulating mitochondrial membrane potential (ΔΨm) and reducing oxidative species. Quercetin can protect against dexamethasone-induced muscle atrophy by regulating the Bax/Bcl-2 ratio at the protein level and abnormal ΔΨm, which leads to the suppression of apoptosis.

Protective effect of Corchorus capsularis L. leaves on ethanol-induced acute gastric mucosal lesion in rats.

In Taiwan, Corchorus capsularis L. has long been cultivated and the leaves are consumed as edible vegetable. This study is to investigate the protection effect of extract of C. capsularis leaves (ECC) on ethanol-induced acute gastric mucosal lesion (AGML) in rats. The results of phytochemical determination in ECC for total polyphenol, flavonoid and polysaccharide were 59.88 ± 0.61 mg/g, 86.39 ± 18.0 mg/g and 320.89 ± 6.99 mg/g, respectively. ECC showed significant activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging with IC50 of 0.25 mg/ml. In vivo studies, Sprague-Dawley (SD) rats were randomly divided into five groups: sham, vehicle (control) and low-, medium-, and high-dose ECC (LECC, MECC, HECC; 200, 400, and 1,000 mg/kg/day, respectively). ECC was able to decrease significantly the ulcer index (UI) caused by 80% ethanol in a dose dependent manner. There was no significant effect on growth trend and food intake rate after the administration of ECC in the experimental period. The serum lipid parameters in ECC groups revealed significant increase in glutathione peroxidase (GPx), superoxide dilmutase (SOD) and catalase (CAT), and a decrease in malondialdehyde (MDA). Significant amelioration on pathological lesion score was found in ECC groups compared with the control group (P<0.05). The overall results indicate that ECC has protective effects on ethanol-induced AGML in rats, which could be associated with its antioxidant activity.

Discovery and Study of Novel Antihypertensive Peptides Derived from Cassia obtusifolia Seeds.

Antihypertensive peptides were screened from thermolysin hydrolysate of Cassia obtusifolia seeds (Jue Ming Zi) using two independent bioassay-guided fractionations, reversed-phase high-performance liquid chromatography (RP-HPLC), and strong cation-exchange (SCX) liquid chromatography coupled with angiotensin I-converting enzyme (ACE) inhibitory assay. The identical peptide in the most active RP-HPLC and SCX fractions was simultaneously de novo sequenced as FHAPWK with high-resolution mass spectrometry. FHAPWK (IC50 = 16.83 ± 0.90 µM) was further identified as a competitive inhibitor and a true inhibitor on ACE by a Lineweaver-Burk plot and preincubation experiment, respectively. The molecular docking simulation indicated that FHAPWK could interact with several key residues of the ACE active site, which is consistent with the result of the inhibitory kinetics study. Moreover, its antihypertensive effect was demonstrated using the animal model of spontaneously hypertensive rats. It is concluded that FHAPWK is the first reported antihypertensive peptide derived from thermolysin hydrolysate of C. obtusifolia seeds.

Autophagy and apoptotic machinery caused by Polygonum cuspidatum extract in cisplatin­resistant human oral cancer CAR cells.

Polygonum cuspidatum (Hu Zhang) is a traditional Chinese medicine (TCM) and has been revealed to exert anticancer, anti­angiogenesis, anti­human immunodeficiency virus (HIV), anti­hepatitis B virus, anti­microbial, anti­inflammatory, and neuro­protective bio­activities. However, the effect of P. cuspidatum extract (PCE) on drug­resistant human oral cancer cells regarding cell death is not fully understood yet. The present study was undertaken to explore the induction of autophagic and apoptotic cell death and to investigate their underlying molecular mechanisms in PCE­treated cisplatin­resistant human oral cancer CAR cells. Our results revealed that PCE was determined via HPLC analytic method, and it was revealed that resveratrol may be a major compound in PCE. The data also demonstrated that PCE reduced CAR cell viability in a concentration­ and time­dependent response via an MTT assay. PCE had an extremely low toxicity in human normal gingival fibroblasts (HGF). Autophagic and apoptotic cell death was found after PCE treatment by morphological determination. PCE was revealed to induce autophagy as determined using acridine orange (AO), LC3­GFP, monodansylcadaverine (MDC) and LysoTracker Red staining in CAR cells. In addition, PCE was revealed to induce apoptosis in CAR cells via 4',6­diamidino­2­phenylindole (DAPI)/terminal deoxynucleotidyl transferase dUTP nick­end labeling (TUNEL) double staining. PCE significantly stimulated caspase­9 and ­3 activities as revealed using caspase activity assays. PCE markedly increased the protein levels of Atg5, Atg7, Atg12, Beclin­1, LC3, Bax and cleaved caspase­3, while it decreased the protein expression of Bcl­2 in CAR cells as determined by western blotting. In conclusion, our findings are the first to suggest that PCE may be potentially efficacious for the treatment of cisplatin­resistant human oral cancer.

Far-infrared therapy improves ankle brachial index in hemodialysis patients with peripheral artery disease.

Ankle brachial index (ABI) is a diagnostic tool for peripheral artery disease (PAD), which is an important issue in hemodialysis (HD) patients. We enrolled 198 maintenance HD patients in this study. PAD is defined as ABI ≤ 0.90. Only PAD patients received far-infrared (FIR) therapy using the WS TY101 FIR emitter for 40 min during each HD session, three times weekly for 6 months. The ABI was measured at the bilateral lower extremities for 4 times [pre-dialytic timing (0 min) and 40 min after the initiation of HD session at both day 0 and 6 months after the FIR therapy]. The primary outcome is the change in ABI. There were 51 out of 198 patients with PAD. In comparison with the period without FIR therapy in the 51 PAD patients, 6 months of FIR therapy significantly improved the ABI of the right/left side for 0 min (from 0.77 ± 0.19 to 0.81 ± 0.20, p = 0.027/0.79 ± 0.20 to 0.81 ± 0.17, p = 0.049), 40 min during HD (from 0.73 ± 0.23 to 0.83 ± 0.19, p < 0.001/from 0.77 ± 0.21 to 0.83 ± 0.18, p < 0.001), and the incremental change between 0 and 40 min (from - 0.04 ± 0.14 to 0.05 ± 0.13, p = 0.007/from - 0.05 ± 0.13 to 0.03 ± 0.11, p = 0.012), respectively. In conclusion, the application of FIR therapy for 40 min, three times weekly for 6 months, has improved the ABI of both lower extremities, thus providing a new strategy of PAD treatment in HD patients.

Current status of dialysis and vascular access in Taiwan.

Due to the implementation of the National Health Insurance system in 1995, the number of patients receiving maintenance dialysis has increased rapidly. This contributed to Taiwan to be in an unfortunate position of possessing the highest prevalence of end-stage renal disease globally. Although the age-standardized incidence of end-stage renal disease gradually decreased to -1.1% in 2014, the huge economic burden that comes with dialysis is detrimental to the quality of dialysis treatment. To achieve a balance between economy and quality of care requires multidisciplinary cooperation. Through a variety of chronic kidney disease-related care projects, we have gradually reversed this situation and achieved good results. Further promotion of kidney transplantation and hospice care for terminal patients will improve the situation. With respect to vascular access, the "fistula first" policy is carried out and percutaneous transluminal angioplasty is the mainstay of treatment to resolve vascular access dysfunction. The medical expenses for dialysis and vascular access management are both fully paid for by the National Health Insurance, and patients do not have to worry about the medical expenses. However, the statistics and vascular access monitoring are relatively insufficient in the past. The comprehensive integration of vascular access management into public policy related to kidney disease will complete the missing piece of the puzzle of overall care.

Benzyl isothiocyanate (BITC) triggers mitochondria-mediated apoptotic machinery in human cisplatin-resistant oral cancer CAR cells.

Benzyl isothiocyanate (BITC), a component of dietary food, possesses a powerful anticancer activity. Previous studies have shown that BITC produces a large number of intracellular reactive oxygen species (ROS) and increases intracellular Ca2+ release from endoplasmic reticulum (ER), leading to the activation of the apoptotic mechanism in tumor cells. However, there is not much known regarding the inhibitory effect of BITC on cisplatin-resistant oral cancer cells. The purpose of this study was to examine the anticancer effect and molecular mechanism of BITC on human cisplatin-resistant oral cancer CAR cells. Our results demonstrated that BITC significantly reduced cell viability of CAR cells in a concentration- and time-dependent manner. BITC was found to cause apoptotic cell shrinkage and DNA fragmentation by morphologic observation and TUNEL/DAPI staining. Pretreatment of cells with a specific inhibitor of pan-caspase significantly reduced cell death caused by BITC. Colorimetric assay analyses also showed that the activities of caspase-3 and caspase-9 were elevated in BITC-treated CAR cells. An increase in ROS production and loss of mitochondria membrane potential (ΔΨm) occurred due to BITC exposure and was observed via flow cytometric analysis. Western blotting analyses demonstrated that the protein levels of Bax, Bad, cytochrome c, and cleaved caspase-3 were up-regulated, while those of Bcl-2, Bcl-xL and pro-caspase-9 were down-regulated in CAR cells after BITC challenge. In sum, the mitochondria-dependent pathway might contribute to BITC-induced apoptosis in human cisplatin-resistant oral cancer CAR cells.

Association between Organochlorine Pesticide Levels in Breast Milk and Their Effects on Female Reproduction in a Taiwanese Population.

Only few studies have focused on organochlorine pesticides (OCPs) in breast milk and the related health risks for women in Taiwan. Our goal is to examine breast milk OCPs and their associations with female reproductive function (infertility, gynecological diseases, and menstruation characteristics) as well as their correlation with sociodemographic parameters (age, pre-pregnant body mass index (BMI), annual incomes, population, birth year, and parity) and dietary habit. The breast milk samples were collected in southern Taiwan (n = 68) from 2013 to 2016 and the OCP residues were analyzed using high resolution gas chromatography with low resolution mass spectrometry (HRGC/LRMS). The results show that the most abundant OCP residues in the breast milk was ΣDDT with the geometric mean ± standard deviation of 9.81 ± 7.52 ng−1 lipid−1 followed by ΣHCH (0.539 ± 0.557 ng−1·lipid−1). In the principal component analysis, cis-chlordane (cis-CHL) and γ-HCH were found to be related to participants who received medical treatment for infertility, and 4,4′-DDT was associated with those who received gynecological surgery. The logistic regression showed that the odds ratio (OR) of log γ-hexachlorocyclohexane (γ-HCH) was higher for mothers who had received medical treatment for infertility than for the normal group (OR = 25.6, p = 0.035) after adjustments for age, pre-pregnant BMI, annual income, population (i.e., native-born Taiwanese), birth year, and parity. Cow milk and beef consumption as well as menstruation characteristics such as average menstrual period (>5 days), shortest menstrual period (<3 days), and women who had taken hormonal drugs were significantly associated to several OCP residues in the breast milk. In addition, ΣHCH including β-HCH and γ-HCH was correlated with annual family income and gravidity as well as cow milk and beef consumptions. Overall, γ-HCH exhibited a probable association with the infertility diseases of Taiwanese women, and dietary habit might play an important role in the female Taiwanese exposure to OCPs.

Levels of PCDD/Fs, PBDEs, and PBDD/Fs in Breast Milk from Southern Taiwan.

This study investigates the congener-specific concentrations of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polybrominated dibenzo-p-dioxins/furans (PBDD/Fs), and polybrominated diphenyl ethers (PBDEs) in 25 breast milk samples from southern Taiwan. Most investigated congeners in Taiwanese breast milk are detectable except for PBDD/Fs. The geometric means of PCDD/Fs and PBDEs in the breast milk are 2.44 pg WHO2005-TEQ/g lipid and 2810 pg/g lipid. Several PCDD/F and PBDE congeners were highly correlated to each other like 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF (r = 0.919, p < 0.001). The longest duration of menstruation could be predicted by BDE-153 (ß = 0.252) and 1,2,3,4,6,7,8-HpCDF (ß = 0.345) with adjustment of confounders using a multiple stepwise linear regression model (r = 0.963, p < 0.001).

Effects of Lycium barbarum (goji berry) on dry eye disease in rats.

Lycium barbarum (goji berry) has long been used as a food and traditional herbal medicine. This study aimed to investigate the beneficial effect of the goji berry on dry eye disease in rats. Male Sprague­Dawley rats with induced dry eye disease were randomly assigned to four groups: Vehicle (control), low­dose goji berry extract [GBE; 250 mg/kg/body weight (bw)], median­dose GBE (350 mg/kg/bw), and high­dose GBE (500 mg/kg/bw). Three methods, Schirmer's test, tear break­up time (BUT) measurement and keratoconjunctival fluorescein staining, were used to evaluate the effect of GBE on symptoms of dry eye disease experienced by the rats. The results of the present study revealed that both the Schirmer's test score and tear BUT significantly increased following 1 week of GBE administration. Furthermore, the severity of the keratoconjunctival staining decreased significantly. In addition, the results suggested that administration of GBE may ameliorate dry eye disease symptoms in a dose­dependent manner. There were no mortalities and no apparent abnormal histopathology changes in the liver or kidney tissues of rats administered GBE for 21 consecutive days. Polysaccharides and betaine present in GBE may have important effects in alleviating dry eye disease induced by oxidative stress and inflammation. In conclusion, the goji berry is a safe, functional food with beneficial effects in alleviating dry eye disease.

Inhibitory effect of burdock leaves on elastase and tyrosinase activity.

Burdock (Arctium lappa L.) leaves generate a considerable amount of waste following burdock root harvest in Taiwan. To increase the use of burdock leaves, the present study investigated the optimal methods for producing burdock leaf extract (BLE) with high antioxidant polyphenolic content, including drying methods and solvent extraction concentration. In addition, the elastase and tyrosinase inhibitory activity of BLE was examined. Burdock leaves were dried by four methods: Shadow drying, oven drying, sun drying and freeze-drying. The extract solution was then subjected to total polyphenol content analysis and the method that produced BLE with the highest amount of total antioxidant components was taken forward for further analysis. The 1,1-diphenyl-2-pycrylhydrazyl scavenging, antielastase and antityrosinase activity of the BLE were measured to enable the evaluation of the antioxidant and skin aging-associated enzyme inhibitory activities of BLE. The results indicated that the total polyphenolic content following extraction with ethanol (EtOH) was highest using the freeze-drying method, followed by the oven drying, shadow drying and sun drying methods. BLE yielded a higher polyphenol content and stronger antioxidant activity as the ratio of the aqueous content of the extraction solvent used increased. BLE possesses marked tyrosinase and elastase inhibitory activities, with its antielastase activity notably stronger compared with its antityrosinase activity. These results indicate that the concentration of the extraction solvent was associated with the antioxidant and skin aging-associated enzyme inhibitory activity of BLE. The reactive oxygen species scavenging theory of skin aging may explain the tyrosinase and elastase inhibitory activity of BLE. In conclusion, the optimal method for obtaining BLE with a high antioxidant polyphenolic content was freeze-drying followed by 30-50% EtOH extraction. In addition, the antielastase and antityrosinase activities of the BLE produced may be aid in the development of skincare products with antiwrinkle and skin-evening properties.

Effect of burdock extract on physical performance and physiological fatigue in mice.

Burdock (BD) is a common vegetable with many pharmacological properties. However, few studies have examined the effect of BD on exercise performance and physical fatigue. We aimed to evaluate the potential beneficial effects of BD on fatigue and ergogenic functions following physical challenge in mice. METHODS: Male ICR mice were divided into four groups to receive either vehicle, or BD at 348.5, 697 or 1,742.5 mg/kg/day, by daily oral gavage for 4 weeks. Exercise performance and fatigue were evaluated from forelimb grip strength, exhaustive swimming time, and post-exercise levels of physical fatigue-related biomarkers serum lactate, ammonia, glucose, and creatine kinase (CK). RESULTS: BD supplementation elevated endurance and grip strength in a dose-dependent manner. It also significantly decreased lactate, ammonia, and CK levels after physical challenge. In addition, BD supplementation had few subchronic toxic effects. CONCLUSIONS: Supplementation with BD has a wide spectrum of bioactive effects, including health promotion, performance improvement, and fatigue reduction.