Demethylenetetrahydroberberine protects dopaminergic neurons in a mouse model of Parkinson's disease / 中国天然药物

Parkinson's disease (PD) is a multifactorial disorder of the nervous system where a progressive loss of dopaminergic neurons exist. However, the pathogenesis of PD remains undefined, which becomes the main limitation for the development of clinical PD treatment. Demethylenetetrahydroberberine (DMTHB) is a novel derivative of natural product berberine. This study was aimed to explore the neuroprotective effects and pharmacological mechanism of DMTHB on Parkinson's disease using C57BL/6 mice. A PD model of mice was induced by administration of MPTP (20 mg·kg-1) and probenecid (200 mg·kg-1) twice per week for five weeks. The mice were administered with DMTHB daily by gavage at the dose of 5 and 50 mg·kg-1 for one- week prophylactic treatment and five-week theraputic treatment. The therapeutic effects of DMTHB were evaluated by behavior tests (the open field, rotarod and pole tests), immunohistochemical staining of tyrosine hydroxylase (TH), Nissl staining and biochemical assays. The molecular mechanisms of DMTHB on the key biomarkers of PD pathological states were analyzed by Western blot (WB) and qRT-PCR. DMTHB treatment alleviated the behavioral disorder induced by MPTP-probenecid. Nissl staining and TH staining showed that the damage of dopaminergic neurons in the substantia nigra was remarkably suppressed by DMTHB treatment. Western blot results showed that the ratio of Bcl-2/Bax and TH increased, but the level of α-synuclein (α-syn) was remarkably reduced, which indicated that the apoptosis of dopaminergic neurons in mice was significantly reduced. The protein phosphorylation of p-PI3K, p-AKT and p-mTOR also increased about 2-fold, compared with the model group. Furthermore, qRT-PCR results demonstrated that the mRNA levels of pro-inflammatory cytokines, IL-1β and TNF-α, were reduced, but the level of anti-inflammatory cytokine IL-10 increased after DMTHB treatment. Finally, the cellular assay displayed that DMTHB was also a strong antioxidant to protect neuron cell line PC12 by scavenging ROS. In this study, we demonstrated DMTHB alleviates the behavioral disorder and protects dopaminergic neurons through multiple-target effects includubg anti-apoptotic, anti-inflammatory and antioxidant effects.

Immunolocalization assessment of metastasis-associated protein 1 in human and mouse mature testes and its association with spermatogenesis / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To investigate the stage-specific localization of metastasis-associated protein 1 (MTA1) during spermatogenesis in adult human and mouse testis.</p><p><b>METHODS</b>The immunolocalization of MTA1 was studied by immunohistochemistry and Western blot analysis. The distribution pattern of MTA1 in mouse testis was confirmed by using quantitative analysis of purified spermatogenic cells.</p><p><b>RESULTS</b>The specificity of polyclonal antibody was confirmed by Western blot analysis. MTA1 was found expressed in the nucleus of germ cells, except elongate spermatids, and in the cytoplasm of Sertoli cells; Leydig cells did not show any specific reactivity. MTA1 possessed different distribution patterns in the two species: in humans, the most intensive staining was found in the nucleus of round spermatids and of primary spermatocytes while in mice, the most intense MTA1 staining was in the nucleus of leptotene, zygotene and pachytene spermatocytes. In both species the staining exhibited a cyclic pattern.</p><p><b>CONCLUSION</b>The present communication initially provides new evidence for the potential role of MTA1 in mature testis. In addition, its distinctive expression in germ cells suggests a regulatory role of the peptide during spermatogenesis.</p>

Histone deacetylase inhibitor trichostatin A induced caspase-independent apoptosis in human gastric cancer cell / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Histone deacetylase inhibitors (HDACIs) have been reported to induce apoptosis in cancer cells. The effects of trichostatin A (TSA) on gastric cancer cells have not been well characterized. This study was aimed to explore the effects and mechanisms of TSA on human gastric cancer SGC-7901 cells.</p><p><b>METHODS</b>The cells were treated with TSA and analyzed by cell proliferation assay, Western blot, TUNEL assay, flow cytometry by fluorescein isothiocyanate (FITC) conjugated with Annexin V and PI staining, immunofluorescence analysis, analysis of subcellular fractionation, gene chips and real time polymerase chain reaction (PCR).</p><p><b>RESULTS</b>TSA could inhibit cell growth and induced apoptosis in gastric cancer SGC-7901 cells through the regulation of apoptosis-related genes, such as Bcl-2, Bax and survivin. Further study indicated that the pan-caspase inhibitor z-VAD-fmk did not inhibit the apoptosis induced by TSA, and we did not observe the cleavage of poly ADP ribose polymerase (PARP) after TSA treatment too. In addition, apoptosis inducing factor (AIF) and EndoG were found to translocate from mitochondria to nucleus in the immunofluorescence assay and the Western analysis of subcellular fractionation confirmed the result of immunofluorescence assay.</p><p><b>CONCLUSIONS</b>The apoptosis induced by TSA in gastric cancer SGC-7901 cells involves a caspase-independent pathway.</p>

Distribution characteristic of NDRG2 expression in human fetal tissues / 生理学报

NDRG2, one of the new N-Myc downstream-regulated gene (NDRG) gene families, is believed to be involved in cell growth event. However, the exact function is still unknown. Identification of the tissue or cell types expressing this gene in vivo will provide clues in clarifying its physiological roles. Using RT-PCR and Western blot, we analyzed the expression level of NDRG2 mRNA and protein in human fetal tissues from different gestational ages. The anti-NDRG2 monoclonal antibody, which has been proved to react specifically with NDRG2 protein, was further used to analyze the cellular location of NDRG2 protein in various human fetal tissues by immunohistochemistry. We found that NDRG2 expression was developmentally dynamic, being generally lower in the early stages of development and markedly increasing during the later stages. NDRG2 mRNA and protein distribution were generally consistent in heart and lung. One of the differences was that NDRG2 protein appeared later than mRNA in kidney. Another unmatched expression was found in liver. NDRG2 mRNA appeared later than protein in liver. In human fetal tissues at sixteen and twenty-eight weeks of gestation, NDRG2 protein immunoreactions could be seen in epithelium of small intestine, epithelium of large intestine, superficial layer of epidermis, whisker follicles, epithelium of small bronchus, hepatocytes, cardiac myocytes, thymus corpuscles and epithelium of renal tubule, and the immunoreactions in those tissues from twenty-eight weeks of gestation was stronger than that from sixteen weeks of gestation. In the present study, we demonstrate the expression pattern and cellular location of NDRG2 protein in a large set of human fetal tissues. This is the first demonstration of NDRG2 protein expression in human fetal tissues. Taken together, the results suggest that NDRG2 protein found in a variety of tissues is not a tissue-specific protein, and may play important roles in histogenesis and organogenesis.

Construction and Eukaryotic Expressing of GPI-Anchored Met-RANTES / 中国生物工程杂志

Objective: To express glycosyl-phosphatidylinositol (GPI) modified Met- RANTES fusion protein on Chinese hamster ovary (CHO) cells and to develop a novel immunosuppressant GPI anchored form of Met-RANTES. Methods: The eukaryotic expression vector PEF/GPI-Met-RANTES were constructed and transfected into CHO cells by electroporation. The transfectants were selected with methotrexate (MTX). Expression of the recombinant protein was assessed by flow cytometric analysis, cell immunofluorescence staining and immunogold electron microscopy. Results: The chimeric molecules of GPI anchored form of Met-RANTES including the whole reading frame were constructed, and the sequence was identical to the designed sequence. GPI anchored form of Met-RANTES was stably expressed on CHO- DHFR- cells. Conclusion: A large amount of GPI modified Met-RANTES fusion protein was expressed on CHO cells. GPI anchored form of Met-RANTES may be used as novel immunosuppressant for suppressing reaction in graft rejection.

Regular expression of discoidin domain receptor 2 in the improved adjuvant-induced animal model for rheumatoid arthritis / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the expression of discoidin domain receptor 2 (DDR2) of fibroblast-like synovial cells in improved adjuvant-induced animal (AIA) model for rheumatoid arthritis (RA) and to provide evidence for DDR2's antagonist use clinically.</p><p><b>METHODS</b>AIA was modified by administrating 0.1 mL of complete Freund's adjuvant (CFA, mixed with 5 mg Bacillus Calmette-Guerin vaccine/mL) into rats' right hind paws and 0.125 mL tumor necrosis factor-alpha (2 U/mL) into right ankles and subpatellar fatty tissue. The expression of DDR2 in fibroblast-like synovial cells was assessed using immunohistochemistry, immunofluorescence histochemistry, and in situ hybridization methods. Levels of anti-collagen II antibody were measured using enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>Given the terms mentioned above, we found a more practical rat model, apparently decreasing immunization time (average 3-5 days). DDR2 can be detected upon the 15th day of immunization; expression gradually increased with time going on, and reaching a peak 35 days after immunization before gradually decreasing. Serum anti-collagen II antibody showed similar expression patterns as DDR2, but reached peak later than DDR2, about 40 days after immunization.</p><p><b>CONCLUSION</b>Regular expression of DDR2 in animal models infers its important role in the pathological process of RA.</p>

Expression of Smad1 and Smad5 in the testis of infertile rats with kidney-yang deficiency / 中华男科学杂志

<p><b>OBJECTIVES</b>To study the expression of Smad1 and Smad5 in the testis of infertile rats with adenine-modeled kidney-yang deficiency and the pathological mechanism of infertility with kidney-yang deficiency, attempting to obtain experimental evidence for the prevention and treatment of male infertility.</p><p><b>METHODS</b>Forty-eight 60 d male SD rats were divided randomly into 6 groups with 8 in each: 7 d, 14 d and 21 d kidney-yang deficiency groups, and 7 d, 14 d and 21 d control groups. The experimental rats had been fed with adenine (300 mg/kg) and the expression levels of Smad1 and Smad5 were measured with immunohistochemical SABC method at the 7th, 14th and 21st day.</p><p><b>RESULTS</b>Smad1 immunoreactivity was mainly located in the spermatogonia, spermatocytes and spermatids, and the reactive substance distributed in cytoplasm with negative nuclei. Sertoli cells and Leydig cells were negative. Compared with the control, the expression level of Smad1 was decreased significantly at the 21st day (P < 0.05), but with no significant difference at the 7th and 14th day (P > 0.05). Smad5 immunoreactivity was mainly located in the spermatogonia and spermatocytes, and the reactive substance distributed in cytoplasm with negative nuclei. Compared with the control, the expression level of Smad5 was not significantly different at the 7th day (P > 0.05). The expression of Smad5 was negative at the 14th and the 21st day.</p><p><b>CONCLUSION</b>The weaker expression of Smad1 and no expression of Smad5 may be one of the pathological mechanisms of infertility with adenine-modeled kidney-yang deficiency.</p>

Expression and significance of Rap1A in testes of azoospermic subjects / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To evaluate the Rap1A mRNA expression and its significance in the testes of normal and azoospermic subjects.</p><p><b>METHODS</b>A cDNA microarray that contained Rap1A and some other genes such as RBM, EIF1AY was used to identify the differential gene expression profiles between the normal and azoospermic testes. cDNA probes were prepared by labeling mRNA from azoospermic and normal testicular tissues through reverse transcription with Cy5-dUTP and Cy3-dUTP, respectively. The mixed cDNA probes were then hybridized with cDNA microarray (each containing 4096 unique human cDNA sequences). The fluorescent signals were scanned and the values of Cy5-dUTP and Cy3-dUTP on each spot were analyzed and calculated. In situ hybridization was employed to detect the expression of Rap1A in the testes of 10 fertile and 39 azoospermic subjects.</p><p><b>RESULTS</b>One hundred and twenty-eight differentially expressed genes were found to be possibly related to azoospermia, of which 56 were up-regulated and 72, down-regulated genes. The mRNA expression of Rap1A in the spermatogenic cells of azoospermic was stronger than that in those of the fertile testes.</p><p><b>CONCLUSION</b>Rap1A may play certain roles in the development of azoospermia.</p>

Stage-specific localization of transforming growth factor beta1 and beta3 and their receptors during spermatogenesis in men / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To investigate the stage-specific localization of transforming growth factor (TGF) beta1 and beta3 during spermatogenesis in adult human testis.</p><p><b>METHODS</b>The localization of TGFbeta1 and beta3 was investigated by immunohistochemical staining method employing specific polyclonal antibodies.</p><p><b>RESULTS</b>Both TGFbeta1 and beta3 and their receptors were preponderant in the Leydig cells. TGFbeta1 could not be detected in the seminiferous tubules. TGFbeta3 and TGFbeta-Receptor (R) I were mainly seen in the elongated spermatids, while TGFbeta-RII in the pachytene spermatocytes and weak in the spermatogonia, spermatids and Sertoli cells. Only TGFbeta-RII was detected in the Sertoli cells. TGFbeta3, TGFbeta-RI and TGFbeta-RII showed a staining pattern dependent upon the stages of the seminiferous epithelium cycle.</p><p><b>CONCLUSION</b>TGFbeta isoforms and their receptors are present in the somatic and germ cells of the adult human testis, suggesting their involvement in the regulation of spermatogenesis.</p>

Expression and localization of Smad1, Smad2 and Smad4 proteins in rat testis during postnatal development / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To study the expression and regulation of Smad1, Smad2 and Smad4 proteins (intracellular signaling molecules of transforming growth factor-b family) in rat testis during postnatal development.</p><p><b>METHODS</b>The whole testes were collected from SD rats aged 3, 7, 14, 28 and 90 (adult) days. The cellular localization and developmental changes were examined by immunohistochemistry ABC method with the glucose oxidase-DAB-nickel enhancement technique. Quantitative analysis of the immunostaining was made by the image analysis system. The Smads proteins coexistence in the adult rat testis was tested by the double immune staining for CD14-Smad4 and Smad2-Smad4. The protein expression of Smad during rat testicular development was examined by means of Western blots.</p><p><b>RESULTS</b>Smad1, Smad2 and Smad4 were present throughout testicular development. The immunostaining of Smad1 and Smad2 were present in spermatogenic cells. A positive immunoreactivity was located at the cytoplasm, but the nucleus was negative. Smad1 was immunolocalized at the d14, d28 and adult testes, while Smad2, at the d7, d14, d28 and adult testis. There was positive immunoreaction in the Sertoli cells and Leydig cells as well. The immunolocalization of Smad4 was exclusively at the cytoplasm of Leydig cells and the nuclei were negative throughout the testicular development. No expression was detected in the germ cells. The results of image and statistical analysis showed that generally the expression of Smad1, Smad2 and Smad4 in the testis tended to increase gradually with the growth of the rat.</p><p><b>CONCLUSION</b>The present data provide direct evidences for the molecular mechanism of TGF-bgr action in rat testes during postnatal development and spermatogenesis.</p>

The role of transforming growth factor beta superfamily in male germ cell development / 中华男科学杂志

Transforming growth factor beta (TGF beta) superfamily can regulate the development of primordial germ cell (PGC) and gonocyte. TGF beta, bone morphogenetic protein (BMP), activin, inhibin, and anti-Müllerian hormone (AMH), all of which belong to the TGF beta superfamily, can play important roles in male germ cell development. Their downstream signaling molecules, Smads proteins are involved in the signal transduction pathway. In addition, TGF beta and AMH contribute to the apoptosis during development. Understanding this effect will help to elucidate the molecular mechanism of the early development of male reproductive system and the pathogenesis of testicular cancer.