Extraction Optimization, Structural Characterization, and Anti-Hepatoma Activity of Acidic Polysaccharides From Scutellaria barbata D. Don.

The Chinese medicinal herb Scutellaria barbata D. Don has antitumour effects and is used to treat liver cancer in the clinic. S. barbata polysaccharide (SBP), one of the main active components extracted from S. barbata D. Don, exhibits antitumour activity. However, there is still a lack of research on the extraction optimization, structural characterization, and anti-hepatoma activity of acidic polysaccharides from S. barbata D. Don. In this study, the optimal extraction conditions for SBP were determined by response surface methodology (RSM): the material-liquid ratio was 1:25, the extraction time was 2 h, and the extraction temperature was 90°C. Under these conditions, the average extraction efficiency was 3.85 ± 0.13%. Two water-soluble polysaccharides were isolated from S. barbata D. Don, namely, SBP-1A and SBP-2A, these homogeneous acidic polysaccharide components with average molecular weights of 1.15 × 105 Da and 1.4 × 105 Da, respectively, were obtained at high purity. The results showed that the monosaccharide constituents of the two components were fucose, galactosamine hydrochloride, rhamnose, arabinose, glucosamine hydrochloride, galactose, glucose, xylose, and mannose; the molar ratio of these constituents in SBP-1A was 0.6:0.3:0.6:30.6:3.3:38.4:16.1:8:1.4, and that in SBP-2A was 0.6:0.5:0.8:36.3:4.4:42.7:9.2:3.6:0.7. In addition, SBP-1A and SBP-2A contained uronic acid and ß-glucan, and the residue on the polysaccharide was mainly pyranose. The in vitro results showed that the anti-hepatoma activity of SBP-2A was better than that of SBP-1A and SBP. In addition, SBP-2A significantly enhanced HepG2 cell death, as cell viability was decreased, and SBP-2A induced HepG2 cell apoptosis and blocked the G1 phase. This phenomenon was coupled with the upregulated expression of P53 and Bax/Bcl-2 ratio, as well as the downregulated expression of the cell cycle-regulating protein cyclinD1, CDK4, and Bcl-2 in this study. Further analysis showed that 50 mg/kg SBP-2A inhibited the tumour growth in H22 tumour-bearing mice, with an average inhibition rate of 40.33%. Taken together, SBP-2A, isolated and purified from S. barbata showed good antitumour activity in vivo and in vitro, and SBP-2A may be a candidate drug for further evaluation in cancer prevention. This study provides insight for further research on the molecular mechanism of the anti-hepatoma activity of S. barbata polysaccharide.

Calcium sensing receptor involving in therapy of embryonic stem cell transplantation alleviates acute myocardial infarction by inhibiting apoptosis and oxidative stress in rats.

OBJECTIVES: The aims of the present study were to investigate the expression of calcium sensing receptor (CaSR) at different times in acute myocardial infarction (AMI) rat myocardial tissue after mouse embryonic stem cells (mESCs) transplantation treatment and to assess its effects on apoptosis and oxidative stress of cardiomyocytes. MATERIALS AND METHODS: The AMI rats were treated with mESCs, Calindol (a CaSR agonist) and Calhex231 (a CaSR inhibitor). Serum measurements, Echocardiographic analysis and TUNEL assay were performed. Myocardial ultrastructure changes were viewed by electron microscopy. Additionally, western blotting was used to detect the protein expressions. RESULTS: Compared to the sham group, it was found that the expression levels of CaSR, caspase-3, cytoplasmic cytochrome C (cyt-C) and Bcl2-associated x (Bax), and the levels of Malondialdehyde (MDA) were significantly increased in both AMI and AMI + mESCs + Calindol groups with the development of myocardial infarction. Furthermore, the ultra-microstructure of cardiomyocyte was highly damaged, the expression levels of mitochondrial cyt-C and B-cell lymphoma 2 (Bcl-2) were significantly decreased, and there was decreased activity of superoxide dismutase (SOD). However, the combination of Calhex231 and mESCs transplantation could inhibit these changes. CONCLUSION: Our results suggested that CaSR expression in myocardial tissue of AMI rats was increased over time, and that Calhex231 could enhance the efficacy of ESCs transplantation for the treatment of AMI, which would be a new therapeutic strategy for the treatment of AMI.

[The expression of calcium-sensing receptor in rats with acute myocardial infarction and its effect on cells apoptosis].

OBJECTIVE: To investigate the change of calcium sensing receptor (CaSR) expression at different time in rat tissue with acute myocardial infarction (AMI) and its effect on cardiomyocyte apoptosis. METHODS: The healthy Wistar rats were randomly divided into Sham and AMI groups, the rat myocardial infarction model was established by ligating left anterior descending coronary artery. The changes of cardiac morphology and hemodynamics were detected at 1, 2 and 4 weeks,respectively. The expressions of CaSR mRNA and protein in myocardial tissue were detected by RT-PCR and Western blot, respectively. The expressions of Bax, Bcl-2, caspase-3 and caspase-9 proteins were detected by Western blot. The serum levels of lactate dehydrogenase (LDH), creatine kinase (CK) activity and cardiac troponin (cTnT) were determined. The apoptosis of cardiomyocytes were tested by TUNEL staining. RESULTS: Compared with the sham group, the expressions of CaSR mRNA and protein, the apoptosis index were increased significantly with the development of AMI (P＜0.05). The ultrastructural damage of cardiomyocytes was serious; the levels of LVSP, +dp/dtmax and -dp/dtmax were decreased,while the levels of LVEDP was increased (P＜0.05); In AMI group, the cTnT level, CK and LDH activities were all increased (P＜0.05). With the development of myocardial infarction, the cTnT level and CK activity were gradually decreased, while the activity of LDH was not significantly changed. The expressions of promote apoptosis-related Bax, caspase-3 and caspase-9 were significantly increased, and the expression of inhibited apoptosis-related protein(factor)Bcl-2 was significantly decreased (P＜0.05). CONCLUSION: With the development of myocardial infarction,the expressions of CaSR mRNA and protein,the apoptosis index in rat myocardial tissue were increased with time prolongation after AMI. The increased expression of CaSR is involved in rat myocardial infarction, which is related with apoptosis.

Scutellaria barbata polysaccharides inhibit tumor growth and affect the serum proteomic profiling of hepatoma H22­bearing mice.

The present study aimed to evaluate the antitumor effect of Scutellaria barbata polysaccharides (SBPS) in a hepatoma mouse model and examine the serum proteins involved in the tumorigenesis and SBPS treatment. A hepatoma model was established by the subcutaneous inoculation of murine hepatocellular carcinoma into Kunming mice. The treatment (once a day) lasted until the tumor weight in the model group was ~1 g (~7­10 days after inoculation). The sera proteins from each group were then collected and subjected to two­dimensional gel electrophoresis. Differentially expressed proteins were screened out and representatives were identified using matrix­assisted laser desorption ionization time­of­flight mass spectrometry. SBPS treatment at different doses significantly inhibited hepatoma growth (all P<0.01 vs. model group). The comparative serum proteomics showed that pseudouridine synthase 1 and chain A of the signal recognition particle Alu RNA­binding heterodimer (Srp9/14) were increased in the serum of the H22 hepatoma­bearing mice, and both were reduced by SBPS treatment. Mitochondrial ribosomal protein L24 was absent from the serum of H22 hepatoma­bearing mice, and was restored by SBPS treatment to approximately the normal level. Taken together, SBPS inhibited the growth of hepatic carcinoma in mice and affected serum proteomic profiling.

Calcium-sensing receptor-mediated mitogen-activated protein kinase pathway improves the status of transplanted mouse embryonic stem cells in rats with acute myocardial infarction.

Several studies have identified the critical role of calcium-sensing receptors (CaSRs) in cardiac ischaemia/reperfusion injury and cardiac hypertrophy and have demonstrated that CaSRs induce myocardial apoptosis by activating MAPKs. Using acute myocardial infarction rat models, we found that a combination therapy of CaSR inhibition and embryonic stem cell (ESC) transplantation after acute myocardial infarction (AMI) leads to a dramatic reduction in the infarct size; a significant increase in the maximum rising and falling rate (+dp/dtmax and -dp/dtmax, respectively) of left ventricular pressure; a significant decrease in left ventricular end-diastolic pressure; a significant decrease in the mRNA expression level of CaSR, Bax, Bcl-2, cleaved caspase-3, cleaved caspase-9, p-ERK, p-JNK and p-P38 protein together with apoptosis indexes in the C and E groups; and a significant decrease in cTnT levels as well as LDH and CK activity. These findings indicate that cardiac function could be enhanced significantly by combination therapy with CaSR inhibition and ESC transplantation; the effect was better than ESC transplantation alone, and the mechanism might be associated with a reduction in cell apoptosis via the inhibition of the MAPK pathway. Apoptosis could be reduced through CaSR, which regulates the MAPK pathway and apoptosis-related protein. Our study indicated that CaSR inhibitors have a pivotal role in the treatment of AMI.

Arsenic trioxide inhibits breast cancer cell growth via microRNA-328/hERG pathway in MCF-7 cells.

Arsenic trioxide (As2O3) has been widely used in the treatment of acute promyelocytic leukemia and has been observed to exhibit therapeutic effects in various types of solid tumor. In a previous study by this group, it was shown that As2O3 induces the apoptosis of MCF-7 breast cancer cells through inhibition of the human ether-à-go-go-related gene (hERG) channel. The present study was designed to further investigate the effect of As2O3 on breast cancer cells and to examine the mechanism underlying the regulation of hERG expression. The present study confirmed that As2O3 inhibited tumor growth in vivo, following MCF-7 cell implantation into nude mice. Using computational prediction , it was identified that microRNA (miR)-328 had a binding site in the 3'-untranslated region of hERG mRNA. A luciferase activity assay demonstrated that hERG is a target gene of miR-328. Further investigation using western blot analysis and reverse transcription-quantitative polymerase chain reaction revealed that As2O3 downregulated hERG expression via upregulation of miR-328 expression in MCF-7 cells. In conclusion, As2O3 was observed to inhibit breast cancer cell growth, at least in part, through the miR-328/hERG pathway.

Ultraperformance liquid chromatography-mass spectrometry based comprehensive metabolomics combined with pattern recognition and network analysis methods for characterization of metabolites and metabolic pathways from biological data sets.

Metabolomics is the study of metabolic changes in biological systems and provides the small molecule fingerprints related to the disease. Extracting biomedical information from large metabolomics data sets by multivariate data analysis is of considerable complexity. Therefore, more efficient and optimizing metabolomics data processing technologies are needed to improve mass spectrometry applications in biomarker discovery. Here, we report the findings of urine metabolomic investigation of hepatitis C virus (HCV) patients by high-throughput ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) coupled with pattern recognition methods (principal component analysis, partial least-squares, and OPLS-DA) and network pharmacology. A total of 20 urinary differential metabolites (13 upregulated and 7 downregulated) were identified and contributed to HCV progress, involve several key metabolic pathways such as taurine and hypotaurine metabolism, glycine, serine and threonine metabolism, histidine metabolism, arginine and proline metabolism, and so forth. Metabolites identified through metabolic profiling may facilitate the development of more accurate marker algorithms to better monitor disease progression. Network analysis validated close contact between these metabolites and implied the importance of the metabolic pathways. Mapping altered metabolites to KEGG pathways identified alterations in a variety of biological processes mediated through complex networks. These findings may be promising to yield a valuable and noninvasive tool that insights into the pathophysiology of HCV and to advance the early diagnosis and monitor the progression of disease. Overall, this investigation illustrates the power of the UPLC-MS platform combined with the pattern recognition and network analysis methods that can engender new insights into HCV pathobiology.

Exploratory urinary metabolic biomarkers and pathways using UPLC-Q-TOF-HDMS coupled with pattern recognition approach.

Metabolomics represents an emerging and powerful discipline concerned with the comprehensive analysis of small molecules and provides a powerful approach to discover biomarkers in biological systems. Recent development of biomarkers for diagnosis and therapeutic monitoring of liver-stagnation and spleen-deficiency syndrome (LSS)-type disease remains challenging. This study was undertaken to discover novel potential biomarkers for the non-invasive early diagnosis of human LSS. Urine samples which are potentially a rich source of metabolites were collected from patients with LSS, together with healthy control samples. Metabolite profiling was performed by ultra-performance liquid-chromatography/electrospray-ionization synapt high-definition mass spectrometry (UPLC-Q-TOF-HDMS) in conjunction with multivariate data analysis and ingenuity pathway analysis that were used to select the metabolites to be used for the non-invasive diagnosis of LSS. Twelve urinary differential metabolites contributing to the complete separation of LSS patients from matched healthy controls were identified involving several key metabolic pathways such as pentose and glucuronate interconversions, ascorbate, aldarate, cysteine, methionine, tyrosine, tryptophan, amino sugar and nucleotide sugar metabolism. More importantly, of the 12 differential metabolites, 4 metabolite markers, prolylhydroxyproline, L-homocystine, 2-octenoylcarnitine and α-N-phenylacetyl-L-glutamine, were effective for the diagnosis of human LSS, with an achieved sensitivity of 93.0%. These results demonstrate that robust metabolomics has the potential as a non-invasive strategy and promising screening tool to evaluate the potential of these metabolites in the early diagnosis of LSS patients and provides new insight into pathophysiological mechanisms.

Urine metabolomics analysis for biomarker discovery and detection of jaundice syndrome in patients with liver disease.

Metabolomics is a powerful new technology that allows for the assessment of global metabolic profiles in easily accessible biofluids and biomarker discovery in order to distinguish between diseased and nondiseased status information. Deciphering the molecular networks that distinguish diseases may lead to the identification of critical biomarkers for disease aggressiveness. However, current diagnostic methods cannot predict typical Jaundice syndrome (JS) in patients with liver disease and little is known about the global metabolomic alterations that characterize JS progression. Emerging metabolomics provides a powerful platform for discovering novel biomarkers and biochemical pathways to improve diagnostic, prognostication, and therapy. Therefore, the aim of this study is to find the potential biomarkers from JS disease by using a nontarget metabolomics method, and test their usefulness in human JS diagnosis. Multivariate data analysis methods were utilized to identify the potential biomarkers. Interestingly, 44 marker metabolites contributing to the complete separation of JS from matched healthy controls were identified. Metabolic pathways (Impact-value≥0.10) including alanine, aspartate, and glutamate metabolism and synthesis and degradation of ketone bodies were found to be disturbed in JS patients. This study demonstrates the possibilities of metabolomics as a diagnostic tool in diseases and provides new insight into pathophysiologic mechanisms.

Expression profiles of microRNAs after focal cerebral ischemia/reperfusion injury in rats.

Rat models of focal cerebral ischemia/reperfusion injury were established by occlusion of the middle cerebral artery. Microarray analysis showed that 24 hours after cerebral ischemia, there were nine up-regulated and 27 down-regulated microRNA genes in cortical tissue. Bioinformatic analysis showed that bcl-2 was the target gene of microRNA-384-5p and microRNA-494, and caspase-3 was the target gene of microRNA-129, microRNA-320 and microRNA-326. Real-time PCR and western blot analyses showed that 24 hours after cerebral ischemia, bcl-2 mRNA and protein levels in brain tissue were significantly decreased, while caspase-3 mRNA and protein levels were significantly increased. This suggests that following cerebral ischemia, differentially expressed microRNA-384-5p, microRNA-494, microRNA-320, microRNA-129 and microRNA-326 can regulate bcl-2 and caspase-3 expression in brain tissue.