Senescence is an inevitable natural life process that involves structural and functional degeneration of tissues and organs. Recently, the process of skin aging has attracted much attention. Determining a means to delay or even reverse skin aging has become a research hotspot in medical cosmetology and anti-aging. Dysfunction in the epidermis and fibroblasts and changes in the composition and content of the extracellular matrix are common pathophysiological manifestations of skin aging. Reactive oxygen species and matrix metalloproteinases play essential roles in this process. Stem cells are pluripotent cells that possess self-replication abilities and can differentiate into multiple functional cells under certain conditions. These cells also possess a strong ability to facilitate tissue repair and regeneration. Stem cell transplantation has the potential for application in anti-aging therapy. Increasing studies have demonstrated that stem cells perform functions through paracrine processes, particularly those involving exosomes. Exosomes are nano-vesicular substances secreted by stem cells that participate in cell-to-cell communication by transporting their contents into target cells. In this chapter, the biological characteristics of exosomes were reviewed, including their effects on extracellular matrix formation, epidermal cell function, fibroblast function and antioxidation. Exosomes derived from stem cells may provide a new means to reverse skin aging.

The dose-toxicity-effect relationship between licorice combined with rhubarb in purgation was studied. A total of 108 ICR mice were divided into control group,model group,positive group,low,medium and high-dose rhubarb groups,and low,medium and high-dose rhubarb-liquorice decoction group. After 6 days of continuous administration of loperamide hydrochloride,the constipation model of mice was replicated,and each group was given lactulose,different doses of rhubarb and rhubarb-liquorice decoction for 14 days. After administration,the defecation characteristics,blood biochemistry,liver,kidney and colon pathological changes in each group were compared. Based on the objective weight given by factor analysis,the dose-toxicity-effect relationship was comprehensively analyzed by multi-index scoring method. Two common factors were extracted by factor analysis,representing effect and toxicity respectively. The results showed that rhubarb could exert a diarrhea effect at the dosage of 1/2,2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,increase the defecation volume and the intestinal tract propulsion rate,reduce the time of anal and the oral transmission,and increase the water content of feces. The combination with licorice could alleviate its diarrhea effect,especially at the dosage of 1/2 times of the high limit set forth in the Chinese Pharmacopoeia. However,rhubarb showed obvious hepatic and colon toxicities at the dosage of 2 and 8 times of the high limit set forth in the Chinese Pharmacopoeia,and the combination with licorice could significantly reduce its toxicity. It shows that licorice has a " mediating" effect on rhubarb by alleviating the purgation property and reducing the toxicity.
Animals ; Cathartics ; pharmacology ; Colon ; Dose-Response Relationship, Drug ; Glycyrrhiza ; chemistry ; Kidney ; Liver ; Mice ; Mice, Inbred ICR ; Plant Extracts ; pharmacology ; Rheum ; chemistry ; Toxicity Tests

Objective To observe the effects of triptolide on drebrin and cofilin expression in the hippocampus of rats with Alzheim-er's disease (AD). Methods Sixty male Sprague-Dawley rats were equally divided into control group, model group and triptolide-treated group with 20 cases in each group. The AD model was established with unilateral injection of beta amyloid 1-40 (Aβ1- 40) into hippocampus in rats. The control group was established with unilateral injection of normal saline with the same volume into hippocampus in rats. The triptolide-treated group was administered triptolide intraperi-toneally, 0.4 mg/kg, once a day, for 15 days after modeling. Spine density of hippocampal neurons was assayed by Golgi staining. Drebrin and cofilin expression of hippocampal neurons was assayed by immunohistochemical staining and reverse transcription polymerase chain reaction (RT-PCR). Results The spine density of hippocampal neurons was higher in the triptolide-treated group than in the model group (P<0.05). The average optical density of drebrin was higher in the triptolide-treated group than in the the model group (P<0.01), while the cell number and average optical density of cofilin were lower (P<0.05). The drebrin mRNA expression was higher in the triptolide-treated group than in the model group (P<0.05), and the cofilin mRNA expression was lower (P<0.01). Conclusion Triptolide may delay the degeneration of dendritic spines in hippocampal neurons of AD rats by regulating the expression of drebrin and cofilin.

OBJECTIVETo simulate the chemical microenvironment of injured brain tissue, and to explore the effect of this chemical microenvironment on temperature sensitive umbilical cord mesenchymal stem cells (tsUC).

METHODSRat models of traumatic brain injury (TBI) were made by fluid percussion injury, and then the brain tissue extracts of the injured regions were acquired. Human umbilical cord mesenchymal stem cells (UC) were isolated and cultured, and the tsUC were obtained through the infection of temperature-sensitive Simian 40 Large T- antigen (ts-SV40LT) retrovirus. After that, both the two kinds of cells were cultured on the polyacrylamide gels which mimicking the elastic modulus of brain. Four groups were included: UC cultured under normal temperature (UC group), UC cultured added brain tissue extract under normal temperature (UC plus extract group), tsUC cultured under mild hypothermia (tsUC group), and tsUC added brain tissue extract under mild hypothermia for 3 days, then normal temperature for 4 days (tsUC plus extract group). After 24 hours, the apoptosis level was checked. Cell growth and morphological changes in each group were given dynamic observation. Seven days later, cell immunofluorescences were implemented for examining neural differentiation level.

RESULTSCompared with UC plus extract group, the apoptosis and proliferation in UC plus extract group were significantly reduced (P < 0.01) and increased (P < 0.01) respectively. Cell immunofluorescence showed that the both GFAP and Neuron positive cells were significantly enhanced in UC plus extract group than those in tsUC plus extract group.

CONCLUSIONtsUC combining with mild hypothermia could significantly reverse injury induced cell apoptosis, improve cell proliferation and neural differentiation under chemical microenvironment after brain injury, which confirmed the adaptation and resistance of tsUC under mild hypothermia after TBI.

Animals ; Apoptosis ; Brain ; cytology ; pathology ; Brain Injuries ; pathology ; Cell Proliferation ; Humans ; Mesenchymal Stromal Cells ; chemistry ; Neurons ; cytology ; Rats ; Temperature ; Umbilical Cord ; cytology

Instruction is the basis for the clinical use of drugs and is the safe and effective legal basis for patient to protect their use of drugs. However, the dosage and usage of the instruction in the clinical practice can not meet the clinical needs, which lead to the excessive usage.In this paper, expert consensus on the excessive use of antimicrobial agents beyond the instruction is interpreted in order to provide reference for clinical medication.

The discovery of induced pluripotent stem cells(iPSCs) is a promising advancement in the field of regenerative medicine. Previous studies have indicated that the teratoma-forming propensity of iPSCs is variable; however, the relationship between tumorigenic potential and genomic instability in human iPSCs (HiPSCs) remains to be fully elucidated. Here, we evaluated the malignant potential of HiPSCs by using both colony formation assays and tumorigenicity tests. We demonstrated that HiPSCs formed tumorigenic colonies when grown in cancer cell culture medium and produced malignancies in immunodeficient mice. Furthermore, we analyzed genomic instability in HiPSCs using whole-genome copy number variation analysis and determined that the extent of genomic instability was related with both the cells' propensity to form colonies and their potential for tumorigenesis. These findings indicate a risk for potential malignancy of HiPSCs derived from genomic instability and suggest that quality control tests, including comprehensive tumorigenicity assays and genomic integrity validation, should be rigorously executed before the clinical application of HiPSCs. In addition, HiPSCs should be generated through the use of combined factors or other approaches that decrease the likelihood of genomic instability.
Animals ; Carcinogenesis ; Cells, Cultured ; DNA Copy Number Variations ; Genomic Instability ; Humans ; Induced Pluripotent Stem Cells ; cytology ; metabolism ; transplantation ; Mice ; Mice, SCID ; NIH 3T3 Cells ; Octamer Transcription Factor-3 ; metabolism ; Teratocarcinoma ; etiology ; Teratoma ; etiology ; Tumor Stem Cell Assay

Brain Neoplasms ; metabolism ; Cell Line, Tumor ; Glioma ; metabolism ; Humans ; Neoplastic Stem Cells ; drug effects ; metabolism ; Reactive Oxygen Species ; metabolism ; Sodium Selenite ; pharmacology

Objective To construct the eukaryotic expression plasmid containing glyceraldehydes-3-phosphate dehydrogenase (GAPDH) and cysteine protease inhibitor ( CPI ) gene from periodic Brugia malayi (Bm) and to lay foundation for studying multivalent vaccines. Methods Total RNA was extracted from periodic Bin. The BmGAPDH and BmCPI genes were amplified by RT-PCR. The PCR product was cloned and then subeloned into eukaryotic recombinant plasmid vector pcDNA3.1 (+). pcDNA3.1 (+)/BmGAPDH/BmCPI was constructed. The recombinant plasmids were screened and identified by digestion with restriction enzyme and PCR amplification, and were transformed into HeLa cell subsequently. The transient expression of BmGAPDH and BmCPI were examined by RT-PCR. The expressed protein was identified by sodium dodeeylsulphate-polyacrylamide gel electrophoresis(SDS-PAGE). Results Two specific bands of around 877 bp of BmGAPDH and 621 bp of BmCPI were amplified, consistent with the expected value. The same bands were obtained by double restriction enzyme digestion of recombinant plasmids or PCR using recombinant plasmid as template. BmGAPDH and BmCPI mRNA were highly expressed in transfeeted HeLa cell. The relative molecular mass (Mr) of the recombinant protein was about 54 × 103. Conclusion The recombinant eukaryotic expression plasmid pcDNA3.1 (+)/BmGAPDH/BmCPI has been constructed successfully and the protein is expressed correctly in mammalian cell.

Objective To clone and sequence the cysteine protease inhibitor gene of periodic Brugia malayi(BmCPI) and predict B-cell epitopes in amino acide sequence of BmCPI in order to provide basis for further study the expression of BmCPI and its function. Methods Total RNA was extracted from periodic Brugia malayi.A couple of specific primers were designed on the basis of known sequences of cysteine protease inhibitor gene from BmCPI. The desired gene was amplified by PCR technique from cDNA. The PCR products were purified and cloned into plasmid pGEM-T by T-A cloning method, transformed into Escherichia coli(E, coli) strain DH5α. The recombinant plasmids were screened and identified by digestion with restriction enzyme and PCR amplification. Five parameters and methods were used to predict B-cell epitopes in amino acide sequence of BmCPI. Results For RT-PCR, a specific band of around 621 bp was amplified. The same band was obtained by double restriction of recombinant plasmids or PCR using recombinant plasmid as template. The result of DNA sequencing showed that BmCPI shares 99% nucleotide sequence identity with that of published sequence. It showed that B-cell epitopes were probably at or adjacent to 23 - 32, 50 - 79 and 117 - 126 in its amino acide sequence. Conclusions pGEM-BmCPI is successfully constructed and sequenced, anticipated objective is reached and conditions is provided for further study of BmCPI expression and its function.

OBJECTIVETo investigate the hypocholesterolemic activity of red yeast rice (RYR) and its underlying mechanism.

METHODSThree groups of hamsters were fed either the control diet or one of the two experimental diets containing by weight 0.1% RYR (0.1RYR) or 0.3% RYR (0.3RYR). Blood (0.5 mL) was collected from the retro-orbital sinus into a heparinized capillary tube at the end of week 0, 3, and 6. Plasma lipoproteins were measured using enzymatic kits, while fecal neutral and acidic sterols were quantified using a gas-liquid chromatography.

RESULTSPlasma total cholesterol was reduced by 12% in 0.1RYR group and by 18% in 0.3RYR group compared with the control value. Similarly, plasma triacylglycerol was decreased by 11% in 0.1RYR group and by 24% in 0.3RYR group. Western blotting analysis demonstrated that RYR had no effect on sterol regulatory element binding protein 2, liver X receptor, 3-hydroxy-3-methylglutary-CoA reductase, LDL receptor, and cholesterol-7alpha-hydroxylase. HPLC analysis confirmed that RYR contained 0.88% monacolin K. It was recently found that RYR supplementation increased excretion of fecal acidic sterols by 3-4 folds compared with the control value.

CONCLUSIONHypocholesterolemic activity of RYR is mediated at least partially by enhancement of acidic sterol excretion.

Animals ; Bile Acids and Salts ; secretion ; Biological Products ; pharmacology ; Blotting, Western ; Body Weight ; drug effects ; Cholesterol ; metabolism ; Cholesterol 7-alpha-Hydroxylase ; metabolism ; Cricetinae ; Dietary Supplements ; Feces ; chemistry ; Feeding Behavior ; drug effects ; Hydroxymethylglutaryl CoA Reductases ; metabolism ; Lipoproteins ; blood ; Liver ; enzymology ; Liver X Receptors ; Naphthalenes ; analysis ; Organ Size ; drug effects ; Orphan Nuclear Receptors ; metabolism ; Receptors, LDL ; metabolism ; Sterol Regulatory Element Binding Protein 2 ; metabolism ; Weight Gain ; drug effects