Blood urea nitrogen to creatinine ratio is associated with physical frailty in older-aged Chinese: a cross-sectional study.

BACKGROUND: The relationship between the ratio of blood urea nitrogen to creatinine (BUN/Cr) and physical frailty in elderly patients remains unclear. The study aims to investigate the association between the BUN/Cr ratio and physical frailty in the elderly Chinese population. METHODS: In this cross-sectional analysis, the clinical data of 5213 participants from 2015 were selected from the China Health and Retirement Longitudinal Study (CHARLS). The demographic variables (including age and gender) and health behavior (including smoking and drinking history), anthropometric (including systolic and diastolic blood pressure, waist circumference (WC), etc.), physical performances (i.e., grip strength, repeated chair stands, etc.), and biochemical indicators (i.e., blood urea nitrogen (BUN), creatinine(Cr), total cholesterol (TC), triglycerides (TG), etc.) were measured. The association between the BUN/Cr ratio and physical frailty was analyzed. RESULTS: After adjusting for potential confounding factors, smooth curve fitting showed a linear relationship between the BUN/Cr ratio and grip strength, a non-linear relationship between the BUN/Cr ratio, and repeated chair-rising time. The fully adjusted linear regression results showed a negative association between the BUN/Cr ratio and grip strength. In the multivariate, piecewise linear regression, when the BUN/Cr ratio was greater than 18.60, the repeated chair-rising time increased with the increase in BUN/Cr ratio (ß = 0.046, 95%CI 0.025, 0.066; p < 0.001). However, we did not observe a significant correlation when the BUN/Cr ratio was less than 18.60 (ß = -0.007, 95%CI -0.046, 0.032; p = 0.717). CONCLUSION: This study demonstrated that the BUN/Cr ratio might be associated with physical frailty in older-aged Chinese, and this association requires further investigation.

Construction and evaluation of endometriosis diagnostic prediction model and immune infiltration based on efferocytosis-related genes.

Background: Endometriosis (EM) is a long-lasting inflammatory disease that is difficult to treat and prevent. Existing research indicates the significance of immune infiltration in the progression of EM. Efferocytosis has an important immunomodulatory function. However, research on the identification and clinical significance of efferocytosis-related genes (EFRGs) in EM is sparse. Methods: The EFRDEGs (differentially expressed efferocytosis-related genes) linked to datasets associated with endometriosis were thoroughly examined utilizing the Gene Expression Omnibus (GEO) and GeneCards databases. The construction of the protein-protein interaction (PPI) and transcription factor (TF) regulatory network of EFRDEGs ensued. Subsequently, machine learning techniques including Univariate logistic regression, LASSO, and SVM classification were applied to filter and pinpoint diagnostic biomarkers. To establish and assess the diagnostic model, ROC analysis, multivariate regression analysis, nomogram, and calibration curve were employed. The CIBERSORT algorithm and single-cell RNA sequencing (scRNA-seq) were employed to explore immune cell infiltration, while the Comparative Toxicogenomics Database (CTD) was utilized for the identification of potential therapeutic drugs for endometriosis. Finally, immunohistochemistry (IHC) and reverse transcription quantitative polymerase chain reaction (RT-qPCR) were utilized to quantify the expression levels of biomarkers in clinical samples of endometriosis. Results: Our findings revealed 13 EFRDEGs associated with EM, and the LASSO and SVM regression model identified six hub genes (ARG2, GAS6, C3, PROS1, CLU, and FGL2). Among these, ARG2, GAS6, and C3 were confirmed as diagnostic biomarkers through multivariate logistic regression analysis. The ROC curve analysis of GSE37837 (AUC = 0.627) and GSE6374 (AUC = 0.635), along with calibration and DCA curve assessments, demonstrated that the nomogram built on these three biomarkers exhibited a commendable predictive capacity for the disease. Notably, the ratio of nine immune cell types exhibited significant differences between eutopic and ectopic endometrial samples, with scRNA-seq highlighting M0 Macrophages, Fibroblasts, and CD8 Tex cells as the cell populations undergoing the most substantial changes in the three biomarkers. Additionally, our study predicted seven potential medications for EM. Finally, the expression levels of the three biomarkers in clinical samples were validated through RT-qPCR and IHC, consistently aligning with the results obtained from the public database. Conclusion: we identified three biomarkers and constructed a diagnostic model for EM in this study, these findings provide valuable insights for subsequent mechanistic research and clinical applications in the field of endometriosis.

Granatin B and punicalagin from Chinese herbal medicine pomegranate peels elicit reactive oxygen species-mediated apoptosis and cell cycle arrest in colorectal cancer cells.

BACKGROUND: Colorectal cancer ranks among the most common cancers. 5-Fluorouracil (5-FU) based first-line chemotherapy for colorectal cancer treatment often leads to chemoresistance and gastrointestinal mucositis. PURPOSE: This study aimed to find potential therapeutic agents from herbal medicine with anti-colorectal cancer and anti-mucositis activities. METHODS: Chinese medicine theory, network pharmacology analyses, and antioxidant activity coupled with liquid chromatography tandem mass spectrometry analyses were used to identify potential bioactive compounds. HT-29 human colorectal cancer cell culture and xenograft tumor models were employed to study anti-colorectal cancer efficacy. Lipopolysaccharide-induced RAW 264.7 and 5-FU treated Dark Agouti rats were used to evaluate anti-inflammatory and anti-mucositis activities. Histological staining, immunofluorescence imaging, western blots, and flow cytometric analyses were employed to explore the underlying mechanisms. RESULTS: Both Chinese medicine theory and network pharmacology analyses indicated pomegranate peels as a potential anti-colorectal cancer and anti-mucositis agent. Antioxidant activity coupled with liquid chromatography tandem mass spectrometry analyses revealed granatin B and punicalagin as the most potent antioxidant compounds in pomegranate peels. Granatin B and punicalagin demonstrated superior anti-colorectal cancer activities in both cell culture and xenograft tumor models. Granatin B and punicalagin also exhibited strong anti-inflammatory activities in lipopolysaccharide-induced RAW264.7 cells and anti-mucositis activities in 5-FU-treated rats. Mechanistic studies revealed that granatin B and punicalagin induced reactive oxygen species-mediated S-phase cell cycle arrest and apoptosis in HT-29 cells. Moreover, these compounds sensitized HT-29 cells to 5-FU-induced cell death and S-phase cell cycle arrest. CONCLUSION: We report that granatin B and punicalagin exhibit superior anti-colorectal cancer and anti-mucositis activities. To the best of our knowledge, these results are novel and suggest that utilizing phenols from herbal medicine, such as granatin B and punicalagin, to target reactive oxygen species may be an innovative therapy to treat colorectal cancer and intestinal mucositis.

Bibliometric analysis of the effects of mental fatigue on athletic performance from 2001 to 2021.

Aims: To explore the research hot topics and main contents in the field of the influence of mental fatigue on athletic performance, and to provide new ideas and directions for future research in this field. Methods: Using CiteSpace and VOSviewer visualization tool software core collection of Web of Science database to TS = ("mental fatigue" OR "mental exertion" OR "cognitive fatigue" OR "Cognitive exertion" OR "mental exhaustion" OR "mental tiredness") AND ("athletic performance" OR "technical skill*" OR "Skill*" OR "technique" OR "decision making" OR "performance") AND ("Humans") searched for the influence of mental fatigue on athletic performance from 2001 to 2021 to conduct visual analysis. Research hot topics were analyzed from the aspects of high-impact countries/regions, institutions, authors, high-frequency keywords, and mutation terms. Results: A total of 658 publications were identified finally, and there has been an increasing trend in the annual number of publications, with the United States ranking first in the number of publications and influence. Future research will focus on promoting the application of EEG technology as an objective indicator for assessing mental fatigue, exploring effective methods and measures for pharmacological or non-pharmacological interventions against fatigue, and focusing on the effects of mental fatigue on endurance performance, technical skills, and sports-related decision-making. Conclusion: The results of the present study help us understand the status of the mental fatigue and athletic performance field and its recent developments.

Dendrobine targeting JNK stress signaling to sensitize chemotoxicity of cisplatin against non-small cell lung cancer cells in vitro and in vivo.

BACKGROUND: Lung cancer is a leading cause of cancer-related death worldwide. Cisplatin-based chemotherapy is the standard treatment for lung cancer, but chemoresistance and adverse effects especially cardiotoxicity limit its efficacy. PURPOSE: The efficacy of combination treatment of dendrobine, a plant alkaloid isolated from Dendrobium nobile, with cisplatin was examined as a possible anti-non-small cell lung cancer strategy. METHODS: The cytotoxicity of dendrobine and cisplatin against A549 lung cancer cells was analyzed by MTT and colony formation assays. Apoptosis was measured by annexin V/PI double staining. Apoptosis-related proteins were assessed by western blotting and qPCR analysis. In vivo efficacy was determined using A549 xenograft in nude mice. JNK and Bim inhibition were achieved by siRNA knockdown and/or chemical inhibition. Cardiotoxicity was assessed by serum creatine phosphokinase activity assay. RESULTS: Dendrobine induced apoptotic cell death through mitochondrial-mediated pathway. Combination treatment of dendrobine with cisplatin showed enhanced cytotoxicity through stimulation of JNK/p38 stress signaling pathways and, consequently, the induction of apoptosis involving pro-apoptotic proteins Bax and Bim. In addition, dendrobine attenuated the body weight reduction and cardiotoxicity induced by cisplatin in nude mice. CONCLUSION: The combination treatment showed enhanced anticancer activity toward non-small cell lung cancer cells without aggravating the cardiotoxic effects of cisplatin suggesting that the combination strategy deserves further investigation for human lung cancer treatment.

Downregulation of Aquaporin 9 Exacerbates Beta-amyloid-induced Neurotoxicity in Alzheimer's Disease Models In vitro and In vivo.

Alzheimer's disease (AD) is the most common cause of dementia in the elderly, characterized by progressive cognitive dysfunction. Aquaporin 9 (AQP9) is an aquaglyceroporin membrane channel shown biophysically to conduct water, glycerol, and other small solutes. In our study, we reported for the first time an age-associated decrease in AQP9 mRNA and protein expressions in both hippocampus and cerebral cortex of APPswe/PS1dE9 (Tg) AD mice at 3, 6 and 10 months of age. Consistently, we observed a dose-dependent downregulation of AQP9 expression in PC12 cells after treatment with amyloid-beta protein 1-40 (Aß1-40). Pre-treatment with AQP9 small interfering RNA led to a more severe neurotoxicity in PC12 cells in response to Aß1-40. Furthermore, we corroborated that the active participation of AQP9 in AD progression is associated with Aß-induced apoptosis both in vitro and in vivo. Taken together, our results reveal an important role of AQP9 in Aß-induced pathogenesis of AD which deserves further investigation.

Ellagitannins from Pomegranate Ameliorates 5-Fluorouracil-Induced Intestinal Mucositis in Rats while Enhancing Its Chemotoxicity against HT-29 Colorectal Cancer Cells through Intrinsic Apoptosis Induction.

Worldwide, colorectal cancer (CRC) is a deleterious disease causing millions of death annually. 5-Fluorouracil (5-FU) is a first-line chemotherapy for CRC, but chemoresistance and gastrointestinal mucositis limit its efficacy. Polyphenol-rich foods are increasingly popular due to their potential beneficial roles in preventing and treating cancer. Ellagitannins are a group of phenolic compounds commonly found in pomegranate, strawberries, raspberries, etc. The objective of this study was to explore whether ellagitannins from pomegranate (PETs) could ameliorate 5-FU-induced intestinal mucositis and enhance the drug's efficacy against CRC. The results showed that PETs (100 mg/kg) counteracted 5-FU-induced intestinal mucositis in rats. The number of apoptotic cells per crypt was reduced from 1.50 ± 0.21 to 0.85 ± 0.18 ( P < 0.05). Moreover, PETs induced HT-29 CRC cell death through intrinsic apoptosis, as demonstrated by dissipation of mitochondrial membrane potential, increased Bax-to-Bcl-2 ratio, and cleavage of caspase 9 and caspase 3. PETs and 5-FU combination treatments exhibited synergistic cytotoxicity against HT-29 cells with a weighted combination index of 0.3494. PETs (80 µg/mL) and 5-FU (40 µg/mL) treatments for 48 h induced 14.03 ± 0.76% and 16.42 ± 1.15% of HT-29 cells to undergo apoptosis, while the combination treatment further increased apoptosis of cells to 34.00 ± 1.54% ( P < 0.05). Combination treatment of the cells also enhanced S phase cell cycle arrest as compared with PETs or 5-FU monotherapy ( P < 0.05). These results suggest that dietary ellagitannins from pomegranate could alleviate intestinal mucositis in rats induced by 5-FU while enhancing its toxicity against HT-29 cells through potentiation of apoptosis and cell cycle arrest.

Smoking cessation affects the natural history of COPD.

BACKGROUND: Cigarette smoking is the most commonly encountered and readily identifiable risk factor for COPD. However, it is not clear which quantitative factors related to smoking influence the prognosis of COPD patients. METHODS: A total of 204 patients with a long-term history of smoking were enrolled into this study and followed up for 5 years. Patients were divided into "death" or "survival" groups based on follow-up results and "quitting-smoking" or "continuing-smoking" groups based on whether they gave up smoking. RESULTS: Patients in the death group had a longer smoking time, lower prevalence of quitting smoking, later onset of COPD symptoms, older age at quitting smoking, lower forced expiratory volume in one second (FEV1) % predicted, and lower ratio of FEV1/forced vital capacity. Age, age at quitting smoking, and FEV1% predicted were independently associated with mortality from COPD. Compared to the continuing-smoking group, the quitting-smoking group had a lower mortality rate, longer course of COPD, earlier onset of COPD symptoms, and lower residual volume percent predicted. During the 5-year follow-up, 113 deaths were recorded (quitting-smoking group: n=92; 40 deaths; continuing-smoking group: n=112; 73 deaths). The mortality risk remained significantly higher in the continuing-smoking group than the quitting-smoking group (log-rank test, 13.59; P=0.0002). CONCLUSION: Smoking time may be related to the mortality rate from COPD. Smoking cessation has the greatest capacity to influence the natural history of COPD.

Ficus virens proanthocyanidins induced apoptosis in breast cancer cells concomitantly ameliorated 5-fluorouracil induced intestinal mucositis in rats.

5-Fluorouracil (5-FU) is a commonly used chemotherapeutic agent for breast cancer. However, its use often leads to drug resistance and mucositis. This study aimed to investigate whether proanthocyanidins from Ficus virens possessed anti-breast cancer and anti-mucositis activities. The results showed that the cytotoxic effects of the proanthocyanidins against MDA-MB-231 and MCF-7 breast cancer cells were in the order of stem barks proanthocyanidins (SPAs) > leaves proanthocyanidins > fruits proanthocyanidins. Moreover, SPAs induced apoptosis in both cell lines which were accompanied with an increase in loss of mitochondrial membrane potential, production of reactive oxygen species, Bax to Bcl-2 protein expression ratio, and activated caspase 3. Furthermore, intraperitoneal injection of 5-FU (150 mg/kg body weight) resulted in body weight loss and jejunal injury in the rats while administration of SPAs (100 mg/kg body weight) counteracted these changes. Collectively, our study demonstrated that SPAs induced apoptosis cell death in breast cancer cells while ameliorating the symptoms of intestinal mucositis in rats.Therefore, SPAs merits further exploration as a potential therapeutic agent for breast cancer and chemotherapy-induced mucositis.

Proanthocyanidins from Uncaria rhynchophylla induced apoptosis in MDA-MB-231 breast cancer cells while enhancing cytotoxic effects of 5-fluorouracil.

Breast cancer is the most frequently diagnosed cancer and cause of cancer death in women worldwide. Current treatments often result in systematic toxicity and drug resistance. Combinational use of non-toxic phytochemicals with chemotherapeutic agents to enhance the efficacy and reduce toxicity would be one promising approach. In this study, bioactive proanthocyanidins from Uncaria rhynchophylla (UPAs) were isolated and their anti-breast cancer effects alone and in combination with 5- fluorouracil (5-FU) were investigated in MDA-MB-231 breast cancer cells. The results showed that UPAs significantly inhibited cell viability and migration ability in a dose-dependent manner. Moreover, UPAs induced apoptosis in a dose-dependent manner which was associated with increased cellular reactive oxygen species production, loss of mitochondrial membrane potential, increases of Bax/Bcl-2 ratio and levels of cleaved caspase 3. Treatments of the cells with UPAs resulted in an increase in G2/M cell cycle arrest. Cytotoxic effects of 5-FU against MDA-MB-231 cells were enhanced by UPAs. The combination treatment of UPAs and 5-FU for 48 h elicited a synergistic cytotoxic effect on MDA-MB-231 cells. Altogether, these data suggest that UPAs are potential therapeutic agents for breast cancer.

Quality and safety control of tumor-shrinking decoction (TSD): A Chinese herbal preparation for the treatment of uterine fibroids.

Reproducible efficacy assessments of Chinese herbal medicines are largely based on well-established quality control procedures. This study presents a comprehensive quality control procedure for tumor-shrinking decoction (TSD), a 15-herb preparation under study as a potential therapy for uterine fibroids. Morphological, microscopic, and physicochemical authentications were first carried out on individual herbal medicines composing TSD. Contaminant tests on TSD for the presence of heavy metals and pesticide residues were performed by atomic absorption spectrophotometry and gas chromatography-mass spectrometry analysis. Furthermore, batch-to-batch quality monitoring of the decoction was investigated via ultra-performance liquid chromatography (UPLC) and high-performance liquid chromatography (HPLC). An aqueous extract of the herbal medicines was prepared and formulated into TSD. The tested contaminants were within the maximum permitted levels of the Hong Kong government in proprietary Chinese medicines. UPLC and HPLC fingerprints for quality tracking on TSD were established. The decoction was quantitatively standardized by UPLC and HPLC, respectively, with five and three chemical compounds serving as references. Collectively, the procedure established in this study will not only serve as a fundamental basis for the investigation and development of TSD as a novel therapy for uterine fibroids, but also as a protocol for studying other polycomponent herbal preparations.

[Change in serum intestinal fatty acid binding protein and its significance in children with pneumonia and gastrointestinal injury].

OBJECTIVE: To study the change in serum intestinal fatty acid binding protein (IFABP) in children with pneumonia and its correlation with gastrointestinal injury. METHODS: A total of 82 children with community-acquired pneumonia who were treated from January to October, 2015 were enrolled, among whom 34 had mild pneumonia and 48 had severe pneumonia. According to pediatric critical illness score (PCIS), the children with severe pneumonia were further divided into non-critical group (25 patients) and critical group (23 patients). Thirty healthy children who underwent physical examination at outpatient service were enrolled as the control group. ELISA was used to measure serum IFABP level, and the acute gastrointestinal injury (AGI) grade was determined for children with severe pneumonia. Serum IFABP level was compared between groups, and the correlations of IFABP with AGI grade and PCIS were analyzed. RESULTS: The severe pneumonia group showed a significantly higher serum IFABP level than the control group and the mild pneumonia group (P<0.01), and the mild pneumonia group also showed a significantly higher serum IFABP level than the control group (P<0.01). The critical group showed a significantly higher serum IFABP level than the non-critical group (P<0.01). The patients with grade I-IV AGI had significantly higher serum IFABP levels than the control group (P<0.01), and the serum IFABP level increased significantly with the increasing AGI grade (P<0.01). Serum IFABP level was positively correlated with AGI grade (P<0.01) but negatively correlated with PCIS (P<0.01). CONCLUSIONS: Children with pneumonia experience an increased serum IFABP level which can be used as a sensitive indicator for the early diagnosis of gastrointestinal injury and the evaluation of conditions in children with pneumonia.

Chinese medicines in the treatment of experimental diabetic nephropathy.

Diabetic nephropathy (DN) is a severe micro vascular complication accompanying diabetes mellitus that affects millions of people worldwide. End-stage renal disease occurs in nearly half of all DN patients, resulting in large medical costs and lost productivity. The course of DN progression is complicated, and effective and safe therapeutic strategies are desired. While the complex nature of DN renders medicines with a single therapeutic target less efficacious, Chinese medicine, with its holistic view targeting the whole system of the patient, has exhibited efficacy for DN management. This review aims to describe the experimental evidence for Chinese medicines in DN management, with an emphasis on the underlying mechanisms, and to discuss the combined use of herbs and drugs in DN treatment.

Antioxidant and antityrosinase proanthocyanidins from Polyalthia longifolia leaves.

In the present study the structure of proanthocyanidins from Polyalthia longifolia leaves was characterized with (13)C nuclear magnetic resonance, high performance liquid chromatography electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses. The results showed that the proanthocyanidins were mixture of homopolymers of B-type procyanidins with degree of polymerization up to 14-mer. Furthermore, the antioxidant activity of the proanthocyanidins was studied through 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free-radical scavenging activities, and ferric reducing/antioxidant power assays. In addition, antityrosinase activity of the proanthocyanidins was investigated. The IC50 for 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) free-radical scavenging activity of the proanthocyanidins were 89.32 ± 12.07 and 76.79 ± 5.88 µg/mL, respectively; the ferric reducing/antioxidant power value was 710.54 ± 142.82 mg ascorbic acid equivalent/g dry weight. The IC50 for antityrosinase activity was 773.09 ± 1.47 µg/mL. In conclusion, the proanthocyanidins from P. longifolia leaves exhibited potent antioxidant and antityrosinase activities. This research would provide scientific evidence for the use of proanthocyanidins from P. longifolia leaves as antioxidant and antityrosinase agents.

Isolation and purification of condensed tannins from flamboyant tree and their antioxidant and antityrosinase activities.

Flamboyant tree, a kind of medicinal plant, was studied as a source of condensed tannins. The antioxidant activities of the condensed tannins from the leaf, fruit, and stem bark of flamboyant tree were screened by ABTS radical and hydroxyl radical scavenging activity methods. The results indicated that these compounds possessed potent antioxidant activity. Their structures were then characterized by high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) after thiolytic degradation. The results showed that the leaf condensed tannins were composed of afzelechin/epiafzelechin, catechin/epicatechin, and gallocatechin/epigallocatechin, while the fruit and stem bark condensed tannins had afzelechin/epiafzelechin and catechin/epicatechin. In addition, the condensed tannins were evaluated for their antityrosinase ability. They were found to have significant antityrosinase activity. The IC50 values were 35 ± 2.0 and 40 ± 0.5 µg/ml for the condensed tannins of fruit and stem bark, respectively. Further, fluorescence quenching and copper interacting techniques were utilized to unravel the molecular mechanisms of the inhibition. The results showed that the hydroxyl group of the condensed tannins could chelate the dicopper center of the enzyme and interact with tryptophan residues. Our studies revealed that condensed tannins might be suitable for use in food, agriculture, cosmetic, nutraceutical, and pharmaceutical applications.

Condensed tannins from Ficus virens as tyrosinase inhibitors: structure, inhibitory activity and molecular mechanism.

Condensed tannins from Ficus virens leaves, fruit, and stem bark were isolated and their structures characterized by 13C nuclear magnetic resonance spectrometry, high performance liquid chromatography electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The results showed that the leaves, fruit, and stem bark condensed tannins were complex mixtures of homo- and heteropolymers of B-type procyanidins and prodelphinidins with degrees of polymerization up to hexamer, dodecamer, and pentadecamer, respectively. Antityrosinase activities of the condensed tannins were studied. The results indicated that the condensed tannins were potent tyrosinase inhibitors. The concentrations for the leaves, fruit, and stem bark condensed tannins leading to 50% enzyme activity were determined to be 131.67, 99.89, and 106.22 µg/ml on monophenolase activity, and 128.42, 43.07, and 74.27 µg/ml on diphenolase activity. The inhibition mechanism, type, and constants of the condensed tannins on the diphenolase activity were further investigated. The results indicated that the condensed tannins were reversible and mixed type inhibitors. Fluorescence quenching, copper interacting, and molecular docking techniques were utilized to unravel the molecular mechanisms of the inhibition. The results showed that the hydroxyl group on the B ring of the condensed tannins could chelate the dicopper irons of the enzyme. Moreover, the condensed tannins could reduce the enzyme product o-quinones into colourless compounds. These results would contribute to the development and design of antityrosinase agents.

Structure characterization of proanthocyanidins from Caryota ochlandra Hance and their bioactivities.

Proanthocyanidins (PAs) from Caryota ochlandra fruit pericarp and fruit flesh were characterized by (13)C nuclear magnetic resonance, high performance liquid chromatography-electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry techniques. The fruit pericarp and flesh PAs were complex mixtures of homo- and heteropolymers of B-type procyanidins and prodelphinidins both with degrees of polymerization up to dodecamer. Their antioxidant and antityrosinase activities were investigated. The fruit pericarp PAs exhibited potent antioxidant activity with IC50 values of 142.86 ± 1.53 and 80.51 ± 0.4 µg/ml for DPPH and ABTS free-radical scavenging assays; with FRAP value of 373.09 ± 5.02 mg ascorbic acid equivalent/g dry weight. Furthermore, the fruit pericarp PAs had antityrosinase activity while the fruit flesh PAs could be oxidized by tyrosinase. The structure and antioxidant activities of the C. ochlandra fruit PAs together with their effects on tyrosinase activity would lay scientific foundation for their utilization in food and nutrition industry.

Optimization of extraction of phenolics from leaves of Ficus virens.

In this research, the conditions for extraction of phenolics from leaves of Ficus virens were optimized using response surface methodology (RSM). The extraction abilities of phenolics (EAP) and flavonoids (EAF), the 2,2-diphenyl-1-pierylhydrazyl (DPPH) free-radical scavenging potential, and the ferric reducing/antioxidant power (FRAP) were used as quality indicators. The results of single-factor experiments showed that temperature, ethanol concentration, extraction time, and the number of extraction cycles were the main influencing variables, and these provided key information for the central composite design. The results of RSM fitted well to a second degree polynomial model and more than 98% of the variability was explained. The ideal extraction conditions for EAP, EAF, DPPH free-radical scavenging potential, and FRAP were obtained. Considering the four quality indicators overall, the ideal extraction conditions were 58% ethanol at 57 °C for 37 min with three extraction cycles. At the ideal extraction conditions, the values of EAP, EAF, DPPH free-radical scavenging potential, and FRAP were 5.72%, 3.09%, 58.88 mg ascorbic acid equivalent (AAE)/g dry weight (DW), and 15.86 mg AAE/g DW, respectively. In addition, linear correlations were observed between EAP, EAF, and antioxidant potential.

Reversible and competitive inhibitory kinetics of amoxicillin on mushroom tyrosinase.

In the present work, we investigated the inhibitory effects of amoxicillin, a bacteriolytic ß-lactam antibiotic drug, on the rate of monophenol hydroxylation and o-diphenol oxidation catalyzed by mushroom tyrosinase. The results showed that amoxicillin could inhibit both monophenolase and diphenolase activities. For monophenolase activity, the inhibition on reaction rate was dose-dependent, while the influence on lag period was not obvious. For diphenolase activity, amoxicillin was found to be a reversible inhibitor, with an IC50 value of 9.0 ± 1.8 mM. Kinetics analysis showed that amoxicillin was a mixed type inhibitor of the enzyme with KI and KIS values of 8.30 mM and 44.79 mM, respectively. Further, the molecular mechanism underlying the inhibition of tyrosinse by amoxicillin was investigated by means of fluorescence quenching and molecular docking techniques. The results showed that amoxicillin could form static interaction with the catalytic pocket of the enzyme through the interaction of amoxicillin with the dicopper irons and amino acid residues in the enzyme active center. Our results contributed to the usage of amoxicillin as a potential tyrosinase inhibitor in the field of medicinal industry and could also provide guidance in the design of novel tyrosinase inhibitors.

Inhibitory effects of Zengshengping fractions on DMBA-induced buccal pouch carcinogenesis in hamsters.

BACKGROUND: Zengshengping (ZSP) tablets had inhibitory effects on oral precancerous lesions by reducing the incidence of oral cancer. However, the severe liver toxicity caused by systemic administration of ZSP limits the long-term use of this anti-cancer drug. The purpose of this study was to evaluate the tumor inhibitory effects due to the topical application of extracts from ZSP, a Chinese herbal drug, on 7, 12-dimethlbenz(a)anthracene (DMBA) induced oral tumors in hamsters. The study also investigated the anti-cancer mechanisms of the ZSP extracts on oral carcinogenesis. METHODS: DMBA (0.5%) was applied topically to the buccal pouches of Syrian golden hamsters (6 - 8 weeks old) three times per week for six weeks in order to induce the development of oral tumors. Different fractions of ZSP were either applied topically to the oral tumor lesions or fed orally at varying dosages to animals with oral tumors for 18 weeks. Tumor volume was measured by histopathological examination. Tumor cell proliferation was evaluated by counting BrdU labeled cells and by Western blotting for mitogen-activated protein kinase (MAPK) protein levels. The protein levels of apoptosis marker Caspase-3 and regulator Bcl-2 protein were also measured by Western blotting. RESULTS: Topical application of DMBA to the left pouch of hamsters induced oral tumor formation. Animals treated with DMBA showed a loss in body weight while animals treated with ZSP maintained normal body weights. Both the ZSP n-butanol fraction and water fraction significantly reduced tumor volume by 32.6% (P < 0.01) and 22.9% (P < 0.01) respectively. Topical application of ZSP also markedly decreased the BrdU-positive cell numbers in oral tumor lesions and reduced the expression level of MAPK. In addition, ZSP promoted tumor cell apoptosis by increasing Caspase-3 expression but decreasing Bcl-2 protein production. CONCLUSION: The n-butanol and water fractions of ZSP are effective at inhibiting tumor cell proliferation and stimulating apoptosis in oral cancer suggesting that these fractions have chemopreventive effects on DMBA induced oral carcinogenesis.