Effect of Dandelion Extracts on the Proliferation of Ovarian Granulosa Cells and Expression of Hormone Receptors / 中华医学杂志(英文版)

<p><b>Background</b>In the current society, infertility related to age has become a social problem. The in vitro fertilization (IVF) success rate in women with poor ovarian response (POR) is very low. Dandelion extract T-1 (DE-T1) is an effective component of the extract from the leaves and stems of Taraxacum officinale, which is one of the medicines used in some patients with POR, but its molecular mechanism remains unclear.</p><p><b>Methods</b>Following IVF, ovarian granulosa cells (GCs) of sixty patients were extracted and divided into normal ovarian response (NOR) and POR groups. GCs were cultured in a dose-dependent and time-dependent manner with DE-T1, proliferation of GCs was determined by Cell Counting Kit-8 assay, and mRNA levels of insulin-like growth factor 1 receptor (IGF-1R), luteotropic hormone receptor (LHR), follicle-stimulating hormone receptor (FSHR), LHR, and CYP19A1 (aromatase) were determined by quantitative polymerase chain reaction. Progesterone and estradiol (E2) concentrations were determined by enzyme-linked immunosorbent assay.</p><p><b>Results</b>The cell viability gradually increased with the progressive increase in the DE-T1 concentration. Compared with the control group (without DE-T1), the mRNA expressions of FSHR, LHR, IGF-1R, and CYP19A1 were upregulated after the addition of DE-T1, especially in the 2.5% DE-T1 group (P < 0.01). The expression of IGF-1R was upregulated approximately 25 times (24.97 ± 4.02 times) in the POR group with 2.5% DE-T1. E2 and progesterone levels increased with the increasing DE-T1 concentration. There were highly significant differences in the E2 and progesterone secretion between the NOR and POR groups (P < 0.01).</p><p><b>Conclusion</b>DE-T1 may promote steroid hormone synthesis by promoting GC proliferation and upregulating GC receptor expression, thereby improving ovarian endocrine function.</p>

Preliminary molecular analysis of bacterial composition in periapical lesions with primary endodontic infections of deciduous teeth / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The bacterial composition of periapical lesions in deciduous teeth has not been well documented. This study was designed to explore the bacterial compositions, especially the dominant bacteria in periapical lesions using 16S rRNA sequencing.</p><p><b>METHODS</b>Tissue samples were collected from 11 periapical lesions in deciduous teeth with primary endodontic infections. DNA was extracted from each sample and analyzed using 16S rRNA cloning and sequencing for the identification of bacteria.</p><p><b>RESULTS</b>All DNA samples were positive for 16S rRNA gene PCR. One hundred and fifty-one phylotypes from 810 clones were identified to eight phyla, and each sample contained an average of 25.9 phylotypes. In addition, 59 phylotypes were detected in more than two samples, and Fusobacterium (F.) nucleatum (8/11), Dialister (D.) invisus (8/11), Campylobacter (C.) gracilis (7/11), Escherichia (E.) coli DH1 (6/11), Aggregatibacter (A.) segnis (6/11), and Streptococcus (S.) mitis (6/11) were the most prevalent species. Furthermore, 45 as-yet-uncultivated phylotypes were also identified.</p><p><b>CONCLUSIONS</b>Chronic periapical lesions in deciduous teeth contained polymicrobial infections. F. nucleatum, D. invisus, C. gracilis, E. coli DH1, A. segnis, and S. mitis were the most prevalent species detected by 16S rRNA sequencing.</p>

Microbial diversity in failed endodontic root-filled teeth / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Persistent/secondary infections of human root canals play an important role in the failure of endodontic treatment. This study used 16S rRNA sequencing to assess microbial diversity in root-filled teeth associated with failed endodontic treatment.</p><p><b>METHODS</b>DNA was extracted from 15 teeth with persistent intraradicular infections, and the 16S rRNA of all present bacteria were amplified by PCR, followed by cloning and sequencing of the 16S rRNA amplicons.</p><p><b>RESULTS</b>All sample extracts were positive for PCR amplification using the universal 16S rRNA gene primers. Negative control reactions yielded no amplicons. Sixty-five phylotypes belonging to seven phyla were identified from 760 clones; a mean of 9.4 phylotypes were detected in each sample (range 3 - 15). Twenty-eight phylotypes were detected in more than one sample, revealing a high inter-sample variability. Parvimonas micra (60%, 9/15), Solobacterium moore (47%, 7/15), Dialister invisus (33%, 5/15), Enterococcus faecalis (33%, 5/15), Filifactor alocis (27%, 4/15), and Fusobacterium nucleatum (27%, 4/15) were the prevalent species. Nineteen as-yet-uncultivated phylotypes were identified, comprising a substantial proportion of the bacteria in many cases.</p><p><b>CONCLUSIONS</b>Persistent intraradicular infections were present in all root-filled teeth associated with failed endodontic treatment. The current observations reveal new candidate endodontic pathogens, including as-yet-uncultivated bacteria and phylotypes that may participate in the mixed infections associated with post-treatment apical periodontitis.</p>

RNA interference mediated silencing of alpha-synuclein in MN9D cells and its effects on cell viability / 神经科学通报·英文版

<p><b>OBJECTIVE</b>To silence the expression of alpha-synuclein in MN9D dopaminergic cells using vector mediated RNA interference (RNAi) and examined its effects on cell proliferation and viability.</p><p><b>METHODS</b>We identified two 19-nucleotide stretches within the coding region of the alpha-synuclein gene and designed three sets of oligonucleotides to generate double-stranded (ds) oligos. The ds oligos were inserted into the pENTR/H1/TO vector and transfected into MN9D dopaminergic cells. alpha-Synuclein expression was detected by RT-PCR, real-time PCR, immunocytochemistry staining and Western blot. In addition, we measured cell proliferation using growth curves and cell viability by 3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di- phenytetrazoliumromide (MTT).</p><p><b>RESULTS</b>The mRNA and protein levels of alpha-synuclein gene were significantly down-regulated in pSH2/alpha-SYN-transfected cells compared with control MN9D and pSH/CON-transfected MN9D cells, while pSH1/alpha-SYN-transfected cells showed no significant difference. Silencing alpha-synuclein expression does not affect cell proliferation but may decrease cell viability.</p><p><b>CONCLUSION</b>Our results demonstrated pSH2/alpha-SYN is an effective small interfering RNA (siRNA) sequence and potent silencing of mouse alpha-synuclein expression in MN9D cells by vector-based RNAi, which provides the tools for studying the normal function of alpha-synuclein and examining its role in Parkinson's disease (PD) pathogenesis. alpha-Synuclein may be important for the viability of MN9D cells, and loss of alpha-synuclein may induce cell injury directly or indirectly.</p>

Astrocytes protect MN9D neuronal cells against rotenone-induced oxidative stress by a glutathione-dependent mechanism / 生理学报

Astrocytes maintain homeostasis of neuronal microenvironment, provide metabolic and trophic support to neurons and modulate neuronal responses to injury. Rotenone specifically inhibits mitochondrial complex I, and long exposure to rotenone may increase the risk for Parkinson's disease (PD) and cause Parkinsonism. However, little is known about the role of astrocytes in the process of rotenone-induced dopaminergic neuron injury. In order to investigate this issue, we used MN9D cells as a cell model of dopaminergic neurons and rotenone as a toxin to initiate mitochondrial deficiency. MN9D cells treated with the normal medium or astrocyte-conditioned medium (ACM) were exposed to different concentrations of rotenone for different time followed by cell viability measurement by MTT assay. Besides, various concentrations of ACM and temporally different treatments were devised to evaluate protective efficiency of ACM. Growth curve of cells in the normal medium or ACM was continuously assessed by cell counting for 8 d. The influence of rotenone and ACM on cellular oxidative stress was determined by DCFH-DA staining followed by flow cytometric analysis. Glutathione (GSH) content after treatment of ACM or rotenone was measured by GSH assay kit. Our results showed that rotenone decreased viability of MN9D cells in a dose-dependent manner and ACM treatment significantly attenuated rotenone toxicity at each concentration. No significant difference in growth rate was observed between the normal medium and ACM treatment. Four concentrations of ACM, namely 1/3ACM, 1/2ACM, 2/3ACM and pure ACM, all displayed protection, increasing cell viability to (124.15+/-0.79)%, (126.59+/-0.82) %, (125.84+/-0.61) % and (117.15+/-1.63) % of the cells exposed directly to rotenone, respectively. Treatment with ACM through the whole experiment except the initial 24 h, 24 h before or at the same time of rotenone addition all exerted protective effects, with cell viability being (110.11+/-2.52)%, (113.30+/-2.36) %, (114.42+/-2.00)% of the cells exposed directly to rotenone, respectively. Conversely, ACM treatment 12 h after rotenone addition had no protective effect, with cell viability being (102.54+/-1.36)% of the cells exposed directly to rotenone. Moreover, ACM treatment up-regulated GSH level in MN9D cells nearly twofold. Incubation with 100 nmol/L rotenone for 24 h depleted GSH level by nearly two thirds of the control, but ACM treatment mitigated the drop of GSH level, maintaining its content at (147.83+/-0.63)% of the control. Consistent with GSH change, rotenone administration resulted in a positive rate of 96.24% of DCF staining, implying a great extent of oxidative stress, whereas treatment with ACM reduced the extent of oxidative stress to a positive rate of 78.31%. Taken together, these findings suggest that astrocytes protect MN9D cells from oxidative stress caused by rotenone, and GSH partially accounts for the protection. Therefore, astrocytes may play a protective role in the process of PD.

Overexpression of alpha-synuclein in SH-SY5Y cells partially protected against oxidative stress induced by rotenone / 生理学报

Both genetic and environmental factors are involved in the pathogenesis of Parkinsonos disease (PD). Epidemiological studies showed that environmental factors shared with the common mechanisms of resulting in alpha-synuclein aggregation by inhibiting complex I of mitochondria and leading to oxidative stress. To investigate the relationship between alpha-synuclein and oxidative stress, we used human dopaminergic SH-SY5Y cells transfected with alpha-synuclein-enhanced green fluorescent protein (EGFP). alpha-synuclein gene expression was determined by immunocytochemistry and real-time quantitative PCR. Both SH-SY5Y and alpha-synuclein overexpressed SH-SY5Y (SH-SY5Y/Syn) cells were treated with various concentrations of rotenone for different time. Cell viability and oxidative stress were detected by MTT assay and DCF assay. Superoxide dismutase (SOD) activity was assessed with xanthine peroxidase method. Cell apoptosis was detected with flow cytometry. Results showed that alpha-synuclein gene was constantly overexpressed in SH-SY5Y/Syn cells. After treatment with rotenone, both cell viability and complex I activity in these cells were reduced in a concentration-dependent manner. Oxidative stress was also found in these cells. Compared with SH-SY5Y cells, SOD activity in SH-SY5Y/Syn cells was increased distinctly (P<0.05) and alpha-synuclein significantly attenuated rotenone-induced cell apoptosis. These results suggest that the alpha-synuclein overexpression in SH-SY5Y cells has a tendency to partially resist oxidative stress induced by rotenone and this response may assist cell survival.

N-terminal of ?-Synuclein Involved in Regulation of Mitochondrial Function / 中国生物工程杂志

Objective: To identify the functional domain of ?-Synuclein in affecting mitochondrial function and how the function to be impaired,especially,the mitochondrial membrane potential and the release of Cytochrome c.Methods: Harvest of ?-Syn-N and ?-Syn-△N by PCR,then subcloned into the pCMV-Myc mammalian expression vector.The recombinant plasmids were transfected into HEK293T cells by Lipofectamine 2000.After detecting the protein expression by Western blot,the functional domain was detected by co-immunoprecipitation.The mitochondrial membrane potential through flow cytometry and immunofluorescence,at the same time,the release of Cytochrome c through flow cytometry to detect.Results: The recombinant plasmids were constructed successfully.CO-IP has proved that N-terminal may be the functional domain of ?-Synuclein in affecting mitochondria.Over-expression of N-terminal could depolarize the mitochondrial membrane potential and induce the Cytochrome c releasing in MN9D cells.Conclusion: N-terminal may be the functional domain of ?-synuclein and over-expression of N-terminal could decrease mitochondrial activity.

Therapeutic Benefit of TH,AADC,and GCH-I Genes for Parkinson's Disease in Rat Model / 中国生物工程杂志

Parkinson's disease(PD) is a common neurodegenerative disorder with no effective protective treatment,characterized by a massive degeneration of dopaminergic neurons in the substantia nigra(SNpc) and the subsequent loss of their projecting nerve fibers in the striatum.The major neurochemical manifestation of this disorder is the loss of the neurotransmitter dopamine(DA) in the striatum as a result of the progressive degeneration of the dopaminergic neurons in the substantia nigra.There have been significant progresses in recent years reporting on the use of mesenchymal stem cells(MSCs)in gene therapy,with specific application towards PD.MSCs,a kind of multipotent adult progenitor cells,are considered as a useful vehicle for cell and gene therapy because of their multiple differentiation potentiality and self-transplantation.The present study was focused on treating rat model of PD using human tyrosine hydroxylase gene(hTH),human aromatic L-amino acid decarboxylase gene(hAADC) and human GT Pcyclohydrolase I gene(hGCH-I) engineered MSCs,in order to provide a better understanding about the application of these cells in the therapeutic benifit of PD.The gene of hTH,hAADC and hGCH-I were introduced via recombinant adeno-associated virus(rAAV) infection into the MSCs in vitro.The genetically modified MSCs expressing hTH,hAADC and hGCH-I were transplanted into the striatum of PD rat models.The behavior,the nigra-striatal level of DA and its metabolite were detected.The results of present study were shown as follows:hTH,hAADC,hGCH-I and LacZ gene were transfected into MSCs with adeno-associated virus vectors.The HEK293 packaging cells(ATCC) were transfected with the plasmids of pAAV-hTH,pAAV-hAADC,pAAV-hGCH-I,pAAV-LacZ,pAAV-RC,pHelper by using calcium phosphate precipitation.Titer was detected using HT1080 cells.Viral particles were collected and used to infect MSCs.The purified modified MSCs expressing the three kinds of genes were selected separately and were grafted in the striatum of the PD model rats in the lesion side.The MSCs genetically modified suvived well 12 weeks after transplantation.The improvements of the behavior were observed every week after transplantation.Compared with the control group,the rounds of asymmetric rotation after apomorphine administration decreased in the groups double or triple genes engineered MSCs grafted(p

Study on the Role of ?-synuclein in Mitochondria Dysfunction Caused by Small Dosage Rotenone / 中国生物工程杂志

Mitochondrial dysfunction has been implicated in the aetiology of sporadic Parkinson's disease but its role in the disease mechanism remains unclear.To investigate the effect of synuclein on mitochondrial dysfunction induced by rotenone.The human dopaminergic SH-SY5Y cells were used as a cell model.The cells over-expressed the wild-type ?-synuclein were treated with complex I inhibitor rotenone.The cell viability,complex I activity,Mitochondrial swelling and O2-content were tested at different time point-1w,2w,4w after rotenone treated.CCK-8 test results showed that the cell viability of overexpressed ?-synuclein(SH-SY5Y-Syn)was much lower than the control group(SH-SY5Y-Ctr).After administrating with rotenone about 1w or 2w the cell viability of SH-SY5Y-Syn became higher than that of SH-SY5Y-Ctr.On the 4th week the results were contrary to the first 2 weeks.Similar results were got when test the mitochondrial function.In the first 2 weeks after roteoone administrating,the mitochondrial function of SH-SY5Y-Syn was better than that of SH-SY5Y-Ctr.This suggest that the ?-synuclein could protect the mitochondrial against the injury induced by rotenone in the early stage-1w,2w,while this effect disappeared in the final stage-4w.

Expression and assessment of double genes of tyrosine hydroxylase gene and aromatic L-amino acid decarboxylase gene in vitro / 生理学报

The characteristic pathological changes of Parkinson s disease (PD) include a severe loss of dopamine neurons in the substantia nigra and a severe decrease in dopamine in the striatum. Since the expression of tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC) in the biosynthetic pathway for dopamine are low, a promising approach to the gene therapy of PD is to augment the gene expression of the enzymes in the biosynthetic pathway for dopamine. In the present study, human TH and AADC genes were reconstructed into retrovirous vectors pLHCX and pLNCX(2) respectively. Then pLHCX/TH and pLNCX(2)/AADC were transfected into packaging cell line PA317 with liposome. PA317/TH and PA317/AADC were selected by different antibiotics. Gene expression was examined by methods of immunohistochemistry and in situ hybridization. The catalytic activity of two cloned gene enzymes was assessed in vitro by HPLC-EC. Immunocytochemical staining showed that TH and AADC were expressed efficiently in vitro. Both TH and AADC mRNA were transcripted in PA317 cell lines by using in situ hybridazation. HPLC-EC experiments revealed that the transfected cells produced a significantly higher level of dopamine and L-dopa than the untransfected cells. The two genetically modified cells could improve the production of L-dopa and dopamine in response to suitable substrate. The present results suggest that not only recombinant TH and AADC genes are successfully expressed in vitro, but also the enzymes have respective functional activities. These results have set up a way for in vivo gene therapy of PD with TH and AADC genes.