Protective effect of thymoquinone on glycation of human myoglobin induced by d-ribose.

Nonenzymatic glycation and the subsequent accumulation of advanced glycation end-products (AGEs) in proteins are factors underlying long-term pathogenesis in diabetes. The study of protein glycation is crucial for elucidating their relationship with diabetes mellitus and related disorders. This study explores the interaction between d-ribose and human myoglobin (HMb), as well as the protective effect of thymoquinone (TQ) on glycation. A time-dependent in-vitro glycation study was performed to investigate the mechanism of d-ribose-induced structural interference of HMb in the absence and presence of TQ. Spectroscopic and proteomic analysis indicated that the presence of TQ significantly reduced the total amount of AGEs while maintaining structural characteristics of HMb. 14 glycated sites on HMb were further identified via liquid chromatography-tandem mass spectrometry (LC-MS/MS) after incubation with d-ribose for 12 h, predominantly interacting with lysine residues. TQ was found to disrupt this interaction, reducing the glycated sites from 14 to 12 sites and the percentage of glycated peptides from 26.50 % to 12.97 %. Additionally, there was a significant decrease in the degree of glycation at the same sites. In summary, our findings suggest that TQ has the potential to act as an anti-glycation agent and provide a comprehensive understanding underlying the inhibition mechanism of glycation.

Bioactivity-guided isolation of compounds from Sophora flavescens with antibacterial activity against Acinetobacter baumannii.

Bioactivity-guided fraction of an extract of Sophora flavescens to identify antibacterial compounds against Acinetobacter baumannii, led to the isolation of two new compounds, (2″R)-5-methoxy-7-hydroxy-8-lavandulylchromone (13) and (2S,ßS)-(-)-sophobiflavonoid CE (19), and 18 known flavonoids, (6aR,11aR)-(-)-maackiain (1), (2S)-(-)-8-prenylnaringenin (2), (2S)-(-)-exiguaflavanone K (3), (2S)-(-)-sophoraflavanone G (4), (2S)-(-)-leachianone A (5), (2S)-(-)-kushenol E (6), (2S)-(-)-leachianone G (7), (±)-kushenol F (8), (2S)-(-)-kurarinone (9), (2S)-(-)-kurarinol (10), (2 R,3R)- (+)-3,7,4'-trihydroxy-5-methoxy-8-prenylflavanone (11), (2S)-(-)-isoxanthohumol (12), (2S)-(-)-2'-methoxykurarinone (14), (2 R,3R)-(+)-kushenol I (15), calycosin (16), kuraridin (17), (2S)-(-)-kushenol A (18), and trifolirhizin (20). Their structures were elucidated based on NMR, MS, and CD spectroscopic analysis. Among them, 1, 2, 5, and 15 exerted modest antibacterial activity against A. baumannii, with MIC95 of 128-256 µg/mL for 2 and 256-512 µg/mL for 1, 5 and 15.

[Optimization of SFE-CO2 Extraction for Ursolic Acid from Punica granatum Peel by Plackett-Burman and Central Composite Design].

OBJECTIVE: The optimum extraction of ursolic acid from Punica granatum peel by SFE-CO2 was investigated. METHODS: Based on the design of Plackett-Burman(PB), significant factors influencing the yield of ursolic acid in the operation process were filtered, with the extraction rate of ursolic acid as the index. The results obtained by steepest ascent method approximated the maximum area of ursolic acid yield. Then the Central Composite Design(CCD) design was used to carry on the response surface optimization of significant factors, getting a two order mathematical model affecting the ursolic acid yield, as well as the optimum process conditions. RESULTS: The best technological conditions of the extraction of ursolic acid from Punica granatum peel by SFE-CO2 were that the extraction temperature was 46. 29 °C, extraction time was 91. 6 min and the extraction pressure was 34. 49 MPa. Under the optimal conditions, verification test of ursolic acid yield was 12. 508 mg/g, approximating to the predicted value of 12. 645 mg/g. CONCLUSION: The PB test and CCD test design are combined to optimize the extraction process of ursolic acid from Punica granatum peel by SFE-CO2. The screening results are statistically significant and the process operation is feasible.

[Mass Transfer Kinetics Model of Ultrasonic Extraction of Pomegranate Peel Polyphenols].

OBJECTIVE: The dynamic mathematical model of ultrasonic extraction of polyphenols from pomegranate peel was constructed with the Fick's second law as the theoretical basis. METHODS: The spherical model was selected, with mass concentrations of pomegranate peel polyphenols as the index, 50% ethanol as the extraction solvent and ultrasonic extraction as the extraction method. In different test conditions including the liquid ratio, extraction temperature and extraction time, a series of kinetic parameters were solved, such as the extraction process (k), relative raffinate rate, surface diffusion coefficient(D(S)), half life (t½) and the apparent activation energy (E(a)). RESULTS: With the extraction temperature increasing, k and D(S) were gradually increased with t½ decreasing,which indicated that the elevated temperature was favorable to the extraction of pomegranate peel polyphenols. The exponential equation of relative raffinate rate showed that the established numerical dynamics model fitted the extraction of pomegranate peel polyphenols, and the relationship between the reaction conditions and pomegranate peel polyphenols concentration was well reflected by the model. CONCLUSION: Based on the experimental results, a feasible and reliable kinetic model for ultrasonic extraction of polyphenols from pomegranate peel is established, which can be used for the optimization control of engineering magnifying production.

[The isolation and identification of bone marrow mesenchymal stem cells derived from rabbit mandible].

PURPOSE: To investigate the methods of isolation, culture and identification of BMMSCs derived from rabbit mandible. METHODS: BMMSCs were collected from rabbit mandible and isolated by density gradient centrifugation. Cells were adherently cultured in vitro, and P2 or P3 BMMSCs populations were collected and examined. Cell growth was observed by inverted microscopy; the propagation of BMMSCs were tested by MTT and a growth curve was drawn after statistical analysis; colony-forming unit-fibroblast(CFU-F) was detected by examination of colony formation; the potential of multi-directional differentiation into osteoblasts, adipocytes and skeletal muscle cells was estimated by pertinent methods; the surface marks of BMMSCs were detected by flow cytometry, the data was analysed using SPSS16.0 software package. RESULTS: The majority of adherent cells were long fusiform, and few were small triangle; the growth curve of BMMSCs showed that every passage experienced incubation period, log phase and platform period; the rate of colony formation was 37%. Growth of BMMSCs represented the appearance of CFU-F; BMMSCs after inducted differentiation showed osteogenic and adipogenic potential. The staining of mineralized nodules was positive by alizarin red S and the positive staining of oil red O appeared in lipid drops around cell nucleus. The staining of skeletal muscle cells was positive by desmin immunofluorescence; the cell surface marks assessed with flow cytometry indicated that these BMMSCs expressed CD90 and CD146 in high percentage (about 98.7% and 98.1%, respectively). CONCLUSIONS: The highly uniformed BMMSCs derived from rabbit mandible can be collected. These BMMSCs have the ability of self-replication and propagation, as well as potential of multi-directional differentiation in vitro.

[Study of dahuangzhechong pills on anti-arterial thrombosis with the orthogonal design].

OBJECTIVE: To screen the main component of Dahuangzhechong pill's anti-arterial thrombosis with the orthogonal design and refine Dahuangzhechong pills. METHODS: In accordance with the orthogonal design table (L(16)2(15)), divided herbs into 16 groups and made the appropriate liquid. The liquid was gave to SD rats by intragastric administration,the model group, normal control group received the same volume of physiological saline. Isolated rats' carotid artery after intragastric administration a week,modeled according to ferric chloride inducement the carotid artery thrombosis method, then collected blood, detected content of platelet, thromboxane B2 (TXB2) and 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha), sheared and measured dry weight of the modeling artery, then placed arteries in 10% formalin fixation, observed morphological changes in vascular tissue by HE staining. RESULTS: Pathological examination revealed: each experimental group had thrombosis, softening, dissolution, absorption, and intimal injury, but the severity of thrombosis were diferent. Orthogonal analysis showed: 1, influence on dry weight of thrombus: rhubarb, ground beetle, leeches, peach seed, dry paint, except dry paint P<0.05, the others P<0.01.2, influence on plasma 6- keto-PGF1alpha level: peach seed, dry paint, ground beetle, gadfly, grubs, leeches, rhubarb, except rhubarb P<0.05, the others P<0.01.3, influence on plasma TXB2: ground beetle, peach seed, dried paint, rhubarb, leeches, except leech P<0.05, the others P<0.01.4, influence on platelet count: peach seed, dry paint, rhubarb, ground beetle, gadfly, leeches, except gadfly, leeches P<0.05, the others P<0.01. CONCLUSION: Anti-artery thrombosis of Dahuangzhechong Pill is most closely related with rhubarb, ground beetle, leeches, peach seed, dry paint and gadfly.

[An epidemiological study on factors affecting serum thyroglobulin levels].

OBJECTIVE: To investigate the effects of several factors affecting serum thyroglobulin (TG) levels among people aged 14 or more. METHODS: We selected Panshan with median urinary iodine (MUI) 83.45 micro g/L as a deficient iodine intake community, Zhangwu with MUI 242.85 micro g/L as a sufficient iodine intake community and Huanghua with MUI 650.87 micro g/L as an excessive iodine intake community. Serum TG and thyroid stimulating hormone (TSH) were measured in 3,335 subjects whose thyroglobulin antibody (TGAb) were negative and thyroid volume were examined using B-ultrasound. RESULTS: In the population with MUI of 80 - 650 micro g/L, serum TG levels presented a "V" curve. An elevated serum TG was found in both the communities with deficient iodine intake and excessive iodine intake. The same trend was shown in the groups with different levels of serum TSH. An elevated serum TG was found in both the groups of TSH < 0.3 mU/L and TSH > 4.8 mU/L. The serum TG levels was positively correlated with thyroid volume and was higher in female subjects than in male. An increased serum TG was found in subjects of aged 50 in the community with deficient iodine intake. CONCLUSION: Serum TG level is affected by gender, amount of iodine intake, serum TSH level and thyroid volume.