• Food Science and Biotechnology
• /
• 제16권1호
• /
• pp.55-61
• /
• 2007

The antioxidant activities of water, ethanol, methanol, and chloroform extracts of Ulmus davidiana were evaluated using various antioxidant assays: DPPH (1,1-diphenyl-2-pricrylhydrazyl) free radical scavenging; hydroxyl radical scavenging; lipid peroxidation scavenging; and reducing power assays. All extracts, except the chloroform extract, demonstrated strong antioxidant activity in all assays. The chloroform extract had the highest hydroxyl radical scavenging activity, and its activity was equivalent to $\alpha$-tocopherol at a concentration of 0.5 mg/mL. Additionally, the antidiabetic activity of their extracts was also evaluated using a rat intestinal $\alpha$-glucosidase inhibition assay. Among all extracts investigated, the methanol extract had the highest $\alpha$-glucosidase inhibitory activity, although its activity was less than acarbose at $0.5\;{\mu}g/mL$. This result suggested that U. davidiana extracts may have antidiabetic activity. Total phenolic compounds and flavonoids were also measured. Phenolic compounds such as tannic acid, p-coumatric acid, and kaempferol were detected by high-performance liquid chromatography (HPLC). These results suggest that U. davidiana extracts may be useful as a potential source of antioxidant and antidiabetic materials.

• 한국미생물·생명공학회지
• /
• 제40권3호
• /
• pp.180-185
• /
• 2012

Type 2 Diabetes Mellitus, a chronic metabolic disorder which results from a high blood glucose level, is one of the most prevalent and costly diseases of our time. Considering increasing rates of obesity and the aging population in Korea, the number of diabetic patients is likely to rise rapidly in the future. There are five conventional diabetic drugs which work through different mechanisms; sulfonylureas, biguanide, meglitinide, alpha-glucosidase inhibitors, and thiazolidinedione. Although they all have antidiabetic effects, some side effects such as hypoglycemia, weight gain and gastrointestinal intolerance are associated with them. Incretin based therapies, utilizing glucagon-like peptide-1 (GLP-1) and dipeptidyl peptidase-4 (DPP-4) inhibitors, which have a lower risk of adverse side effects, have recently been introduced. At present PPAR-targeting drugs are being actively developed. In this research review, particular emphasis has been placed on the current trends and possible biological targets for the new generation of antidiabetic drugs.

• 약학회지
• /
• 제47권1호
• /
• pp.52-55
• /
• 2003

Antidiabetic activities of white ginseng 50％ ethanol extract (WGE) and IH901, an intestinal metabolite of ginsenoside R $b_1$, were compared in multiple low dose streptozotocin (STZ)-induced diabetic rats. WGE or IH901 were coadministered with STZ on Day 1 at dose of 100 and 300 mg or 10 and 30 mg, respectively, and continually administered for 16 days. STZ dissolved in citrate boner was injected intraperitoneally at dose of 20 mg/kg for 5 consecutive days. During the experiment, plasma glucose level and body weight were measured every 4$^{th}$ day. Amount of food and water intake were evaluated once a week and compared between groups. WGE and IH901 both significantly reduced the plasma glucose levels on Day 16 as compared with those of the diabetic control group. In the meantime, amount of food and water intake in WGE-and IH901-treated groups were significantly improved in a dose dependent fashion as compared with those of the diabetic control group. Taken together WGE and IH901 showed the comparable antidiabetic activities at the corresponding doses used in this experiment.

• Journal of the Korean Wood Science and Technology
• /
• 제47권4호
• /
• pp.498-508
• /
• 2019

This study was carried out to investigate the potential of Korean red pine (Pinus densiflora) inner bark extracts as an antidiabetic agent. The ethyl acetate soluble fraction of the bark extracts was chromatographed on a Sephadex LH-20 column to yield five compounds, which structures were elucidated by NMR spectroscopy. The isolated compounds were (+)-catehin, (-)-epicatechin, taxifolin, taxifolin-3'-O-${\beta}$-D-(+)-glucose and $\tilde{n}$-courmaric acid. The antidiabetic activity of the different fractions, including the crude extracts and isolated compounds, was evaluated by ${\beta}$-cells insulin secretion and glucose uptake in skeletal muscle cells. The insulin secretion was 128% for taxifolin at $25{\mu}g/mL$. However, the other samples had no effect on this test. For the glucose uptake activity assay, $1{\mu}M$ insulin and 2 mM metformin were used as controls. Both the crude extract and taxifolin showed relatively low activity values, but the other samples yielded glucose uptake values over 260%. ${\rho}$-courmaric acid showed the highest uptake (270%). The results confirmed that Korean red pine extracts may be used as a hypoglycemic agent.

• Journal of Microbiology and Biotechnology
• /
• 제29권5호
• /
• pp.713-720
• /
• 2019

Acanthamoeba castellanii belonging to the T4 genotype may cause a fatal brain infection known as granulomatous amoebic encephalitis, and the vision-threatening eye infection Acanthamoeba keratitis. The aim of this study was to evaluate the antiamoebic effects of three clinically available antidiabetic drugs, Glimepiride, Vildagliptin and Repaglinide, against A. castellanii belonging to the T4 genotype. Furthermore, we attempted to conjugate these drugs with silver nanoparticles (AgNPs) to enhance their antiamoebic effects. Amoebicidal, encystation, excystation, and host cell cytotoxicity assays were performed to unravel any antiacanthamoebic effects. Vildagliptin conjugated silver nanoparticles (Vgt-AgNPs) characterized by spectroscopic techniques and atomic force microscopy were synthesized. All three drugs showed antiamoebic effects against A. castellanii and significantly blocked the encystation. These drugs also showed significant cysticidal effects and reduced host cell cytotoxicity caused by A. castellanii. Moreover, Vildagliptin-coated silver nanoparticles were successfully synthesized and are shown to enhance its antiacanthamoebic potency at significantly reduced concentration. The repurposed application of the tested antidiabetic drugs and their nanoparticles against free-living amoeba such as Acanthamoeba castellanii described here is a novel outcome that holds tremendous potential for future applications against devastating infection.

• 한국식생활문화학회지
• /
• 제36권5호
• /
• pp.522-529
• /
• 2021

This study was conducted to analyze the antioxidant and antidiabetic activities of acorns according to the types of Quercus serrata Thunb (QST) and Q. acutissima Carruther (QAC). The total polyphenol contents of the extracts from QST and QAC were 220.59 and 320.96 mg GAE/g, respectively. The content of total polyphenol of QAC was higher than that of QAC (p<0.001). DPPH (2,2 Diphenyl 1 picrylhydrazyl) radical scavenging activity, reducing power and superoxide dismutase (SOD)-like activity were increased in a concentration-dependent manner by both acorn extracts, and QAC showed high activity in all antioxidant experiments (p<0.05). The inhibitory activities of α-glucosidase and α-amylase were also increased in a concentration-dependent manner, and QAC showed higher inhibitory activity than QST (p<0.05). Our study indicates that QST and QAC are functional food materials with high antioxidant and antidiabetic activities. In addition, QAC has a higher physiological activity than QST.

• 대한본초학회지
• /
• 제24권1호
• /
• pp.159-167
• /
• 2009

Objectives : So-Dang-Hwan (SDH) is used as a traditional treatment of diabetes in oriental clinics in Korea. This study aimed to evaluate antidiabetic effect of SDH in streptozotocin (STZ)-induced diabetic rats. Methods : Diabetes was induced by i.p. injection of STZ (45 mg/kg) to Sprague-Dawley rats. Experimental animals (eight per group), were treated by oral administration of SDH (60 mg/kg body weight) and glibenclimide (1 mg/kg), a known antidiabetic drug for comparison, during 5 weeks. To veridy the effect of SDH, the levels of glucose, triglyceride, insulin, BUN and creatinine were measured in sera from experimental diabetic rats, and an oral glucose tolerance test (OGTT) was also performed. Results : SDH prevented body weight loss in diabetic rats. SDH exhibited at termination, a significant reduction in blood glucose levels in STZ-induced diabetic rats. SDH significantly reduced serum creatinine levels toward the normal levels. The OGTT results showed a significant improvement in glucose tolerance in rats treated with SDH. Conclusions : These data indicate that SDH treatment may improve glocose homeostasis in STZ-induced diabetes.

• 생명과학회지
• /
• 제27권5호
• /
• pp.579-583
• /
• 2017

번행초는 주요 화합물인 수용성 다당류와 cerebroside의 작용에 기인하여 기대되는 항궤양성 약용작물이다. 스트렙토조토신 유도 당뇨마우스에서 번행초의 다당 추출물(TPE)의 항당뇨 효과는 이전에 보고된 바가 없다. 본 연구는 체중 1 kg 당 65 mg의 스트렙토조토신을 복강에 주사하여 확립된 당뇨 마우스에서 TPE의 항당뇨 효과를 측정하기 위해 실시하였다. 100 mg 농도의 TPE를 3주간 투여했을 때, 당뇨 마우스의 체중은 유지되었으며, 혈당, 중성지방, 그리고 lactate dehydrogenase, alkaline phosphatase 및 glutamic pyruvic transaminase가 낮은 수준으로 감소함이 관찰되었다. 또한 내당능 실험에서도 TPE의 투여는 대조군인 당뇨 마우스에 비해 혈당 수준을 현저하게 감소시켰으며, 실험 가능한 거의 모든 생화학적 요인을 당뇨마우스에 비해 낮은 수준으로 회복시켰다. 따라서 전통적인 약용작물인 번행초의 잠재적인 항당뇨 효능을 본 연구에서 처음으로 증명하였다.

• 한국임상약학회지
• /
• 제29권3호
• /
• pp.186-192
• /
• 2019

Background: Diabetes is associated with cancer risk in the aging population. Observational studies have indicated the beneficial effects of metformin against breast cancer, making studies on the anticancer potential of antidiabetic drugs worthwhile. This study investigated cancer incidence in patients on antidiabetic monotherapy. Methods: Using National Health Insurance Service data (2002-2013), a retrospective cohort study that included type 2 diabetes mellitus (T2DM) patients was conducted. Study subjects were enrolled if they were ${\geq}30$ years old, on monotherapy for diabetes, and cancer-free. They were followed up for cancer occurrence or death, until December 31st, 2013. A Cox proportional hazard model analysis was conducted between metformin and sulfonylurea (including meglitinide) users, to determine cancer risk, with adjustment for age, gender, comorbidity index, dyslipidemia, hypertension, and T2DM duration. Results: The number of antidiabetic monotherapy-treated T2DM patients without a history of cancer was 9,554 (metformin, n = 5,825; sulfonylurea, n = 3,225; others, n = 504). During the follow-up period (mean, 2.04; IQR, 3.18 years), the cancer incidence rate was 5.48/100 and 5.45/100 patient-years for metformin and sulfonylurea, respectively. The hazard ratio (HR) for risk of cancer incidence in the metformin group was 0.74 (95% confidence interval [CI], 0.66-0.83; p < 0.0001), compared with sulfonylurea. Additionally, the HRs for risks of lung, liver, and stomach cancer were respectively 0.46 (95% CI, 0.31-0.66; p < 0.0001), 0.41 (95% CI, 0.31-0.54; p < 0.0001), and 0.51 (95% CI, 0.35-0.73; p = 0.0003). Conclusion: Antidiabetic therapy with metformin reduces cancer risk by 26%, specifically for lung, liver, and stomach cancer.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
• /
• pp.117-117
• /
• 2003

PPARs (peroxisome proliferator activated receptors) are member of nuclear hormone receptors superfamily. Activations of PPARs upon binding with ligands modulate glucose metabolite, differentiation of adipocyte, inflammation response, and so on. Thiazolidinedione analog is one of potential antidiabetic drug that binds and activates PPARν selectively and enhances insulin sensitivity. In an effort to develop novel and effective antidiabetic thiazolidindione analogs, syntheses of benzoxazole and benzothiazole-linked thiazolidinedione analogs were performed via coupling reaction of benzoxazolylalkylaminoethanol with hydroxybenzylthiazolidinedione to develop novel and effective antidiabetic thiazolidindiones. All compounds were evaluated their biological potency by PPARν transactivation assay and revealed the similar potency with Troglitazone. However, lengthening of N-alkyl substituent did not seem to be beneficial for the activity.