Protective Effect of Procyanidin B2 on Acute Liver Injury Induced by Aflatoxin B in Rats / 生物医学与环境科学（英文）

Objective@#This study aimed to explore the protective effect of procyanidin B2 (PCB2) on acute liver injury induced by aflatoxin B (AFB ) in rats.@*Methods@#Forty Sprague Dawley rats were randomly divided into control, AFB , AFB + PCB2, and PCB2 groups. The latter two groups were administrated PCB2 intragastrically (30 mg/kg body weight) for 7 d, whereas the control and AFB groups were given the same dose of double distilled water intragastrically. On the sixth day of treatment, the AFB and AFB + PCB2 groups were intraperitoneally injected with AFB (2 mg/kg). The control and PCB2 groups were intraperitoneally administered the same dose of dimethyl sulfoxide (DMSO). On the eighth day, all rats were euthanized: serum and liver tissue were isolated for further examination. Hepatic histological features were assessed by hematoxylin and eosin-stained sections. Weight, organ coefficient (liver, spleen, and kidney), liver function (serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total bilirubin, and direct bilirubin), oxidative index (catalase, glutathione, superoxide dismutase, malondialdehyde, and 8-hydroxy-2'-deoxyguanosine), inflammation factor [hepatic interleukin-6 (IL-6) mRNA expression and serum IL-6], and bcl-2/bax ratio were measured.@*Results@#AFB significantly caused hepatic histopathological damage, abnormal liver function, oxidative stress, inflammation, and bcl-2/bax ratio reduction compared with DMSO-treated controls. Our results indicate that PCB2 treatment can partially reverse the adverse liver conditions induced by AFB .@*Conclusion@#Our findings indicate that PCB2 exhibits a protective effect on acute liver injury induced by AFB .

Simultaneous liquid chromatography- tandem mass spectrometry method to quantify epicatechin and procyanidin B2 in rat plasma after oral administration of Trichilia catigua (catuaba) extract and its application to a pharmacokinetic study

Abstract Trichilia catigua A. Juss., Meliaceae, known as catuaba in Brazil, is traditionally used for the treatment of stress, sexual impotence and memory deficits. To our knowledge, there is no analytical method described in literature for simultaneous quantification of catuaba extract marker substances in biological matrices. The aim of this study was to develop and validate a bioanalytical method by LC-MS/MS to quantify epicatechin and procyanidin B2 in rat plasma after administration of standardized extract of T. catigua. Chromatographic separation was achieved with a C18 column, methanol and 0.1% aqueous formic acid at a flow rate of 0.25 ml/min. Detection was performed using electrospray ionization in negative mode. The lower limits of quantification were 5 ng/ml and 12.5 ng/ml for procyanidin B2 and epicatechin, respectively. Intra- and inter-day assays variability were less than 15%. The extraction recovery was 104% for epicatechin and 74% for procyanidin B2 using one-step liquid-liquid extraction with ethyl acetate. Epicatechin and PB2 were detected in plasma up to 300 min after oral administration of 400 mg/kg of standardized extract of T. catigua in rats. This rapid and sensitive method for the analysis of the epicatechin and procyanidin B2 in rat plasma can be applied to pharmacokinetic studies.

Protective effect of procyanidin B2 on intestinal barrier and against enteritis in a mouse model of trinitrobenzene sulphonic acid-induced colitis / 南方医科大学学报

OBJECTIVE@#To investigate the protective effect of procyanidin B2 (PCB2) on the intestinal barrier and against enteritis in mice with trinitrobenzene sulphonic acid (TNBS)-induced colitis and explore the possible mechanism.@*METHODS@#A mouse model of TNBS-induced colitis was established in male Balb/c mice aged 6-8 weeks. The successfully established mouse models were randomly divided into PCB2 treatment group (=10) and model group (=10) and were treated with daily intragastric administration of PCB2 (100 mg/kg, 0.2 mL) and 0.2 mL normal saline, respectively. After 4 weeks, the disease symptoms, intestinal inflammation, intestinal mucosal cell barrier function and the changes in PI3K/AKT signaling were evaluated using HE staining, immunofluorescence assay and Western blotting.@*RESULTS@#The disease activity index of the mice was significantly lower and the mean body weight was significantly greater in PCB2 group than in the model group in the 3rd and 4th weeks of intervention ( < 0.05). The levels of colonic inflammation and intestinal mucosal inflammatory mediators IL-1β and TNF-α were significantly lower while IL-10 was significantly higher in PCB2 group than in the model group ( < 0.05). Compared with those in the model group, the mice in PCB2 treatment group showed a significantly lower positive rate of bacterial translocation in the mesenteric lymph nodes and a lower thiocyanate-dextran permeability of the intestinal mucosa ( < 0.05). Western blotting showed that PCB2 treatment significantly increased the expressions of claudin-1 and ZO-1 ( < 0.05) and significantly lowered the expression levels of p-PI3K and p-AKT in the intestinal mucosa as compared with those in the model group ( < 0.05).@*CONCLUSIONS@#PCB2 suppresses intestinal inflammation and protects intestinal mucosal functions and structural integrity by inhibiting intestinal PI3K/AKT signaling pathway, suggesting the potential of PCB2 as a new drug for Crohn's disease.

Effect of procyanidin B2 on inflammatory mediators of human periodontal ligament cells / 上海交通大学学报（医学版）

Objective: To investigate the effects of procyanidin B2 on the expression of inflammatory mediators in human periodontal ligament cells (hPDLCs) induced by Porphyromonas gingivalis lipopolysaccharide (LPS). Methods: hPDLCs were cultured using tissue explant method in vitro. The effect of procyanidin B2 on the cell viability of hPDLCs was detected by MTT assay. hPDLCs were stimulated by P. gingivalis LPS after treatment with procyanidin B2 for 1 h. The expressions of IL-1β, IL-6, and IL-8 mRNA and proteins were detected by real-time PCR and ELISA assay. Reactive oxygen species (ROS) in the cytoplasm was observed under fluorescence microscope. Nitric oxide (NO) in the supernatant was detected by Griess assay. Results: 100.00 µg/mL procyanidin B2 could enhance the cell viability of hPDLCs. Procyanidin B2 could inhibit the expressions of IL-1β, IL-6, and IL-8 mRNA and proteins in hPDLCs. It could also downregulate ROS and NO in hPDLCs induced by P. gingivalis LPS. Conclusion: Procyanidin B2 can play an anti-inflammatory role by inhibiting inflammatory mediators in hPDLCs induced by P. gingivalis LPS.

Simultaneous determination of procyanidin B1, procyanidin B2, procyanidin B4, rutin, and quercetin in Aronia melanocarpa berry by UPLC / 中草药

Objective: The ultra performance liquid chromatography diode array detection method was used to establish the determination methods for the contents of procyanidin B1, procyanidin B2, procyanidin B4, rutin, and quercetin in Aronia melanocarpa berry. Methods: Waters Acquity UPLC® HSS T3 C18 column (100 mm × 2.1 mm, 1.8 μm) was used. The mobile phase was methanol (A)-0.03% phosphoric acid in water (B) for the gradient elution with flow rate of 0.2 mL/min. The column temperature was 35℃. The determination wavelength for procyanidin B1, procyanidin B2 and procyanidin B4 was 280 nm, and that for rutin and quercetin was 360 nm. Results: There was a linear correlation between the concentration of procyanidin B1 2.2-44.0 μg/mL (r = 0.999 2), procyanidin B2 50-1 000 μg/mL (r = 0.999 5), procyanidin B4 3.6-54.0 μg/mL (r = 0.999 2), rutin 7.4-148.0 μg/mL (r = 0.999 4), and quercetin 2.1-42.0 μg/mL (r = 0.999 7). The average recovery rates of procyanidin B1, procyanidin B2, procyanidin B4, rutin, and quercetin were 101.23% (RSD = 2.13%), 99.64% (RSD = 1.23%), 102.31% (RSD = 2.89%), 98.74% (RSD = 2.96%), and 103.53% (RSD = 2.64%), respectively. The average contents of procyanidin B1, procyanidin B2, procyanidin B4, rutin, and quercetin in Aronia melanocarpa berry were 129.78, 3 834.99, 196.02, 134.40 and 79.10 μg/g, respectively. Conclusion: The analysis method is simple, rapid, reproducible, accurate, and reliable, and can be used to identify and evaluate the quantitative determination of five constituents in A. melanocarpa berry.

Protective effect of procyanidin single active ingredient B2 on human en-dothelial progenitor cells under high glucose stimulation / 中国病理生理杂志

AIM:To study the protective effect of procyanidin single active ingredient B2 (PC-B2) on human endothelial progenitor cells ( EPCs) stimulated with high glucose.METHODS: The human EPCs were isolated from pe-ripheral blood of healthy people and identified.The EPCs were divided into control group (PBS treatment), hypertonic control group (25 mmol/L mannitol treatment), high glucose (30 mmol/L) group, and different concentrations (2, 10 and 50 mg/L) of PC-B2+30 mmol/L glucose groups.The viability of EPCs was detected by CCK-8 assay.The levels of LDH, MDA, SOD and GSH in the EPCs were detected.The changes of NO, ET-1, ICAM-1 and VCAM-1 in the EPCs cultured medium were measured by ELISA.The cell apoptotic rate and reactive oxygen species ( ROS) in the EPCs were analyzed by flow cytometry.The expression of VEGF and VEGFR-2 in the EPCs were determined by Western blot.RE-SULTS:Compared with control group, the viability of human EPCs was decreased significantly in 30 mmol/L glucose group (P cantly (P<0.05), but SOD and GSH activity and NO production were decreased significantly (P<0.05).The ROS and cell apoptotic rate were increased significantly (P<0.05).The expression of VEGF and VEGFR-2 in the EPCs were de-creased (P<0.05).When human EPCs were treated with different concentrations of PC-B2 and 30 mmol/L glucose, the viability was obviously rebounded (P<0.05), the LDH leakage, MDA content and the releases of ET-1, ICAM-1 and VCAM-1 were decreased gradually (P<0.05), the SOD, GSH activity and NO production were increased significantly (P<0.05), the ROS and cell apoptotic rate were decreased significantly (P<0.05), and the expression of VEGF and VEGFR-2 in the EPCs was increased gradually ( P <0.05 ) .CONCLUSION: PC-B2 enhances the viability of human EPCs under high glucose condition, reduces high glucose-induced oxidative damage, restores the EPCs normal function, and reduces the releases of inflammatory cytokines and apoptosis, thus playing a protective effect on human EPCs through inducing the expression of VEGF and VEGFR-2.

Determination of catechin,epicatechin,gaIIic acid and procyanidin B2 in procy-anidins by RP-HPLC / 中国药科大学学报

To develop a RP-HPLC method for the determination of catechin (C),epicatechin (EC),gallic acid (GA)and procyanidin B2 (PCB2 )in procyanidins and compare the contents of C,EC,GA and PCB2 in procyani-dins purchased from different manufacturers.A RP-HPLC method was developed and the determination was car-ried out on a Hypersil ODS2 column (4.0 mm ×200 mm,5 μm).The mobile phase consisted of methanol and 2% acetic acid with gradient elution and the detection wave-length was at 280 nm.There was a good linear rela-tionship between concentration and the peak area in the range of 0.1-50 μg/mL (r =0.998 6)for catechin,0.1-50 μg/mL (r =0.994 5)for epicatechin,0.05-50 μg/mL (r =0.999 9)for gallic acid and 0.1-50 μg/mL (r =0.992 2)for procyanidin B2 ,respectively.The average recoveries of catechin,epicatechin,gallic acid and PCB2 were 98.36%,98.21%,89.60% and 98.47%,respectively and the RSDs were 1.39%,0.84%,2.12% and 2.46%,respectively.The method is simple,accurate,reproducible and can be used for assay of C,EC,GA,PCB2 in procyanidins.There was a great difference in the content of four substance in procyanidins purchased from dif-ferent manufacturers.

Chemical constituents in root tuber of Tetrastigma hemsleyanum and their anti-oxidative activities / 中草药

Objective: To study the chemical compositions from the root tuber of Tetrastigma hemsleyanum and their anti-oxidative activities. Methods: The compounds were isolated by various column chromatography. Their structures were identified by spectroscopic methods including 1H-NMR, 13C-NMR, MS, HR-MS, etc. The anti-oxidative activities were evaluated by DPPH radical scavenging assay. Results: Fourteen compounds were isolated from the root tuber of T. hemsleyanum, they were identified as kaempferol (1), quercetin (2), salicylic acid (3), benzoic acid (4), oxyresveratrol (5), catechin (6), L-epicatechin (7), epigallocatechin (8), procyanidin B2 (9), procyanidin B1 (10), 3-O-caffeoylquinic acid (11), protocatechualdehyde (12), p-hydroxybenzoic acid (13), and protocatechuic acid (14). The anti-oxidative IC50 values of compounds 2, 8, 9, 10, and 12 were 14.15, 14.19, 15.99, 12.4, and 15.98 μmol/L, respectively, better than the positive control Vit C (IC50 value was 23.0 μmol/L). Conclusion: Compounds 4-12 are isolated from T. hemsleyanum for the first time. It has been demonstrated that the root tuber contain flavonoids and also is rich in organic acids. Moreover, compounds 2, 8, 9, 10, and 12 have the certain prospects in the development of natural anti-oxidative agents.

Procyanidin B2 protects LPS-induced myocardial cell apoptosis / 中国药理学通报

Aim To study the mechanisms of the pro-tective effect of procyanidin B2 ( PCB2 ) on the myocar-dial cell apoptosis induced by lipopolysaccharide ( LPS) . Methods Using the primary culture rat myo-cardial cells, myocardial cell injury model was induced by LPS. PCB2 low, medium and high dose groups, were cultured with 6. 25 , 12. 5 , 25. 0 μmol · L-1 PCB2 respectively in DMEM medium for 24 h continu-ously. Myocardial cell survival rate was determined by MTT colorimetric method. Cardiacmyocyte NOX activi-ty was determined by lucigen chemiluminescence meth-od . Western blot analysis was used to detect myocardi-al NADPH oxidase p47phox expression. TUNEL method was used to detect apoptosis and flow cytometry was used to determine the content of myocardial cells ROS. Results Compared with control group, the cell dam-age induced by LPS group myocardial cell survival rate significantly decreased ( P <0. 01 ) , and myocardial cell NOX activity, p47phox expression, apoptotic cell number and ROS content were significantly increased (P<0. 01). PCB2 low, medium and high dose groups cell survival rates were significantly elevated, myocar-dial cell NOX activity and p47phox expression, apoptotic cell number and the ROS content decreased significant-ly in a dose-dependent manner ( P <0. 01 ) . Conclu-sion PCB2 protects myocardial cell apoptosis induced by LPS via inhibiting the expression of NADPH oxidase activation, p47phox expression and reactive oxygen spe-cies generation.

Quality standard for Jinqiaomai Tablets / 中成药

AIM: To establish the quality standard for Jinqiaomai Tablets ( Fagopyri Dibotryis Rhizoma). METHODS: Fagopyri Dibotryis Rhizoma was identified by TLC. The contents of (-)-epicatechin and procyanidin B2 were determined simultaneously by HPLC,the Symmetry C18 column (5 ?m,3. 9 mm id ? 150 mm) was used. The water (adjust pH value to 3. 00 ? 0. 02 with phosphoric acid)-acetonitrile (92 ∶ 8) was used as a mobile phase,the detecting wavelength was at 280 nm. The column temperature was at 35 ℃. RESULTS: Fagopyri Dibotryis Rhizoma could be identified. The calibration curve of (-)-epicatechin was linear in the range of 0. 113 6-2. 272 ?g with the correlation of 0. 999 968 (n = 8). The average recovery of (-)-epicatechin was 97. 12% ,RSD = 0. 92% (n = 6). The calibration curve of procyanidin B2 was linear in the range of 0. 166 4-1. 664 ?g with the correlation of 0. 999 702(n = 8). The average recovery of procyanidin B2 was 98. 26% ,RSD = 0. 61% (n = 6). CONCLUSION: The method is specific,reliable and accurate,so it can be used for the quality control of Jinqiaomai Tablets.

Determination of procyanidin B2 in grape seed extract by RP-HPLC / 中成药

AIM: To establish the method of determining procyanidin B2 content in grape seed extract by HPLC. METHODS: The determination was carried out with ZORBAX SB-C_ 18 column. The mobile phase consisted of acetonitrile-2% acetate buffer under the gradient elution condition, detection wavelength was at 280nm. RESULTS: There was a good linear relationship between the peak area and concentration in the range of 1~30 ?g/mL for procyanidin B2. The average of procyanidin B2 (n=5) was 99.29% and RSD=1.64%, respectively. CONCLUSION: The method is simple, accurate, reproducible and can be used for assay of procyanidin B2.