Chapter Ⅰ
Oxidative stress and aldose reductase activity have been implicated in the development of diabetic complications. In this study, the antioxidant and aldose reductase(AR) inhibitory effects of Maackia amurensis were investigated. The ethyl acetate (EtOAc) fraction of the M. amurensis ex...
Chapter Ⅰ
Oxidative stress and aldose reductase activity have been implicated in the development of diabetic complications. In this study, the antioxidant and aldose reductase(AR) inhibitory effects of Maackia amurensis were investigated. The ethyl acetate (EtOAc) fraction of the M. amurensis extract showed the highest inhibitory activity in oxidative stress and AR. To identify and isolate the active components guided by an offline HPLC-ABTS and HPLC micro-fractionation, the EtOAc fraction of the M. amurensis extract was performed by high-speed countercurrent chromatography and Sephadex LH-20 column chromatography. Four antioxidants, namely piceatannol (IC50 = 6.73 μM), resveratrol (IC50 = 11.05 μM), trans-ferulic acid (IC50 = 13.51 μM) and chlorogenic acid (IC50 = 27.23 μM), and six AR inhibitors, namely chlorogenic acid (IC50 = 4.2 μM), tectoridin (IC50 = 50.4 μM), genistein
(IC50 = 57.1 μM), formononetin (IC50 = 69.2 μM), resveratrol (IC50 = 117.6 μM) and daidzein (IC50 = 151.9 μM), were isolated and identified. The screening results of the offline
HPLC-ABTS and HPLC micro-fractionation was matched the activity results of isolated compounds. Thus, our results indicate that offline HPLC-ABTS and HPLC micro-fractionation is fast, efficient and reproducible for isolating active compounds from complex natural products.
Chapter 2
The aim of this study was to determine the aldose reductase (AR) inhibitory activity and DPPH free radical scavenging activity of components from Agrimonia pilosa Ledeb. We isolated agrimoniin (1), four flavonoid glucosides and two flavonoid glucuronides from the
n-butanol of A. pilosa 50% methanol extract. In addition to isolated compounds, the AR-inhibitory activity and the DPPH free radical scavenging activity of (+)-catechin, five
flavonoids, and four flavonoid glucosides (known components of A. pilosa) against rat lens AR (RLAR) and DPPH assay were measured. Compound 1 showed IC50 values of 1.55 and 13.04 μM against RLAR and DPPH scavenging activity. Additionally, 1, luteolin-7-O-glucuronide (4), quercitrin (5), luteolin and afzelin showed high inhibitory activity against AR and were first observed to decrease sorbitol accumulation in the rat lens under
high-sorbitol conditions ex vivo with inhibitory values of 47.62, 91.83, 76.87, 91.83, and 93.20%, respectively. Inhibition of recombinant human AR by compounds 1, 4 and afzelin exhibited a noncompetitive inhibition pattern. Based on our results, A. pilosa and its constituents may play partial roles in RLAR and oxidative radical inhibition. Our results suggest that compounds 1, 4, and 5, luteolin and afzelin may potentially be used as natural drugs for treating diabetic complications.
Chapter 3
Agrimonia pilosa Ledeb, often used in traditional Chinese medicine, has been previously reported to produce an antinociceptive effect on ICR mice in both tail-flick and
hot-plate tests. Studies have shown that Salvia miltiorrhiza Bunge, also renowned in traditional Chinese medicine, is an effective anti-inflammatory treatment. Among the extraction solvents investigated in this study, a 50% ethanol extract of A. pilosa produced the highest antinociceptive effect in MSU-induced gout pain models and the greatest yield. The 80%EtOH extract of S. miltiorrhiza produced a moderate inhibitory response against LPS-induced NO release from RAW 264.7 murine macrophages and exhibited outstanding yield. Mixture extracts from select A. pilosa and S.miltiorrhiza extracts were evaluated for enhanced
antinociceptive effects in gout arthritis treatment. To control extract quality, four bioactive markers–rutin, apigenin-7-O-glucuronide, tanshinone IIA, and salvianolic acid B–were
determined using an HPLC-DAD method. A 50:50 mg/kg mixture of 50% ethanol extract of A. pilosa and 80% ethanol extract of S.miltiorrhiza produced better results than when the extracts were administered individually. This study suggests that the 50:50 mg/kg mixture extract has significant therapeutic potential for treating gout arthritis.
Chapter Ⅰ
Oxidative stress and aldose reductase activity have been implicated in the development of diabetic complications. In this study, the antioxidant and aldose reductase(AR) inhibitory effects of Maackia amurensis were investigated. The ethyl acetate (EtOAc) fraction of the M. amurensis extract showed the highest inhibitory activity in oxidative stress and AR. To identify and isolate the active components guided by an offline HPLC-ABTS and HPLC micro-fractionation, the EtOAc fraction of the M. amurensis extract was performed by high-speed countercurrent chromatography and Sephadex LH-20 column chromatography. Four antioxidants, namely piceatannol (IC50 = 6.73 μM), resveratrol (IC50 = 11.05 μM), trans-ferulic acid (IC50 = 13.51 μM) and chlorogenic acid (IC50 = 27.23 μM), and six AR inhibitors, namely chlorogenic acid (IC50 = 4.2 μM), tectoridin (IC50 = 50.4 μM), genistein
(IC50 = 57.1 μM), formononetin (IC50 = 69.2 μM), resveratrol (IC50 = 117.6 μM) and daidzein (IC50 = 151.9 μM), were isolated and identified. The screening results of the offline
HPLC-ABTS and HPLC micro-fractionation was matched the activity results of isolated compounds. Thus, our results indicate that offline HPLC-ABTS and HPLC micro-fractionation is fast, efficient and reproducible for isolating active compounds from complex natural products.
Chapter 2
The aim of this study was to determine the aldose reductase (AR) inhibitory activity and DPPH free radical scavenging activity of components from Agrimonia pilosa Ledeb. We isolated agrimoniin (1), four flavonoid glucosides and two flavonoid glucuronides from the
n-butanol of A. pilosa 50% methanol extract. In addition to isolated compounds, the AR-inhibitory activity and the DPPH free radical scavenging activity of (+)-catechin, five
flavonoids, and four flavonoid glucosides (known components of A. pilosa) against rat lens AR (RLAR) and DPPH assay were measured. Compound 1 showed IC50 values of 1.55 and 13.04 μM against RLAR and DPPH scavenging activity. Additionally, 1, luteolin-7-O-glucuronide (4), quercitrin (5), luteolin and afzelin showed high inhibitory activity against AR and were first observed to decrease sorbitol accumulation in the rat lens under
high-sorbitol conditions ex vivo with inhibitory values of 47.62, 91.83, 76.87, 91.83, and 93.20%, respectively. Inhibition of recombinant human AR by compounds 1, 4 and afzelin exhibited a noncompetitive inhibition pattern. Based on our results, A. pilosa and its constituents may play partial roles in RLAR and oxidative radical inhibition. Our results suggest that compounds 1, 4, and 5, luteolin and afzelin may potentially be used as natural drugs for treating diabetic complications.
Chapter 3
Agrimonia pilosa Ledeb, often used in traditional Chinese medicine, has been previously reported to produce an antinociceptive effect on ICR mice in both tail-flick and
hot-plate tests. Studies have shown that Salvia miltiorrhiza Bunge, also renowned in traditional Chinese medicine, is an effective anti-inflammatory treatment. Among the extraction solvents investigated in this study, a 50% ethanol extract of A. pilosa produced the highest antinociceptive effect in MSU-induced gout pain models and the greatest yield. The 80%EtOH extract of S. miltiorrhiza produced a moderate inhibitory response against LPS-induced NO release from RAW 264.7 murine macrophages and exhibited outstanding yield. Mixture extracts from select A. pilosa and S.miltiorrhiza extracts were evaluated for enhanced
antinociceptive effects in gout arthritis treatment. To control extract quality, four bioactive markers–rutin, apigenin-7-O-glucuronide, tanshinone IIA, and salvianolic acid B–were
determined using an HPLC-DAD method. A 50:50 mg/kg mixture of 50% ethanol extract of A. pilosa and 80% ethanol extract of S.miltiorrhiza produced better results than when the extracts were administered individually. This study suggests that the 50:50 mg/kg mixture extract has significant therapeutic potential for treating gout arthritis.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.