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Epidermal growth factor (EGF) plays a role in male germ cell development, but the precise function is yet to be defined. This study shows that EGF stimulates rat spermatogonial proliferation in a dose-dependent manner and significantly increased the protein levels of phosphated c-Src (p-c-Src) and phosphated signal transducer and activator of transcription 3 (p-STAT3). Moreover, overexpression of c-Src tagged with enhanced green fluorescence protein (EGFP) in rat spermatogonial stem cells enhances the cell viability. In contrast, knockdown or inhibition of c-Src inhibits rat spermatogonial stem cell proliferation; EGF could not abrogate the inhibitory effect. Evidently, the content of p-STAT3 protein was increased in c-Src-expressing cells and decreased in c-Src-suppressing cells. Furthermore, knockdown or inhibition of STAT3 also suppressed cell viability; neither EGF nor increased c-Src could reverse the inhibitory effect. These results are the first evidence that EGF induces proliferation of rat spermatogonial stem cells through c-Src/STAT3 signal.

The present study was performed to evaluate the potential protective effects of Shikonin extracted from Zicao on lupus nephritis (LN) using NZB/W F1 mice. Oral administration of Shikonin (24, 40 mg/kg body weight/d) or vehicle was applied to sixty female NZB/W F1 mice of 28-week-old with LN. Treatment with Shikonin for 14 weeks suppressed proteinuria dose-dependently with the mean proteinuria of 274.0 mg/dl and 160.3 mg/dl for low-dose and high-dose Shikonin groups, respectively, compared to 499.2 mg/dl for the vehicle. Also, Shikonin was observed to reduce circulating adhesion molecules significantly and down-regulate intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) mRNA expression in kidney. However, anti-double stranded (ds)DNA antibody in mice with low or high Shikonin dose administration both exhibited no significant elevation, differing from vehicle group. Kidney histological examination showed that renal glomerular lesions were alleviated after Shikonin application. These results suggest that Shikonin has therapeutic effects on LN in NZB/W F1 mice, to which inhibition of anti-dsDNA may be potential contribution, and its part mechanism is related to suppression of mRNA expression of cell adhesion molecules (CAMs) in the kidney.

To observe the effect of TCM therapy for detoxification, removing stasis, and nourishing yin on corticosteroid-induced hyperlipemia in patients with systemic lupus erythematosus (SLE), and to investigate its mechanism. One hundred and seventy patients with SLE were randomly assigned to the integrative medicine group (IM group) and the Western medicine group (WM group), 85 in each group. Also, 30 healthy subjects selected from blood donors were enrolled in the normal control (NC) group. All patients were treated mainly with prednisone, while those in the IM group were given TCM therapy additionally, and the therapeutic course for both groups was 6 successive months. The changes of serum total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C) and apolipoprotein A (ApoA) were determined and observed. A 2-year follow-up study was carried out in 16 patients of the WM group and 25 of the IM group. Before treatment, no significant difference had been found among the three groups in the serum levels of lipids and lipoproteins. After the 6-month treatment, as compared with the WM group, the IM group showed lower levels of TC, TG, LDL-C, and VLDL-C (P

Five antibodies against vascular endothelial growth factor 165 (VEGF165) were obtained. These antibodies, Ab-2, Ab-20, Ab-153, Ab-309, Ab-342, were able to recognize not only native VEGF165, but also reducing VEGF165. Three of the antibodies, Ab-153, Ab-309, Ab-342, were identified as VEGF165 neutralizing antibody on the basis of its ability to inhibit the proliferation of human umbilical vein endothelial cells (HUVEC) induced by VEGF165 and the binding of [125I]-VEGF165 to receptors on HUVEC. The fragments of E1 (VEGF120-135) and E2 (VEGF46-60) recognized by neutralizing antibodies may be related the receptor binding domain of VEGF.

HBp17 was purified by Heparin-Copper biaffinity chromatography and HPLC from conditioned medium of A431 cell. The purified HBp17 was digested by staphylococcus urcus V8 protease or chymotrypsin and the heparin-binding fragments were isolated by Heparin-Sepharose. One binding site of peptide mapping is HBp17 residues 110-145 produced by V8. Another one is HBp17 residues 82-143 which were produced by chymotrypsin digestion. Two binding sites of peptide mapping are overlap. Therefore the residues 110-143 of HBp17 are the principle heparin binding site. The basic amino acid cluster in this region may be contribute to the binding of HBp17 to heparin or heparan sulfate proteoglycan on the cell surface and extracellular matrix.

The biotransformation of adrenocorticotropin (ACTH-(1-39)) by brain synaptic membranes has been studied. Peptide fragments of ACTH-(1-39) which were formed during in vitro incubation of the peptide with membrane preparations were isolated by high pressure liquid chromatography and characterized by determination of amino acid composition and NH2- terminal residue. At pH 7.4, ACTH-(1-38) was found as the main metabolite, together with ACTH-(7-21) and ACTH-(7-20). In addition, a series of secondary products was identified. At pH 6.2, ACTH-(1-38), ACTH-(1-37), and ACTH-(1-36) were exclusively formed, while at pH 8.5, ACTH-(1-39) was converted into ACTH-(1-16), ACTH-(17-39), ACTH-(22-39), and ACTH-(3-15). Time course experiments demonstrated the action of a carboxypeptidase activity and a trypsin-like endopeptidase on ACTH-(1-39) as predominant proteolytic events. The carboxypeptidase was optimally active at pH values of 5.7 or below. These enzymes play an essential role in the stepwise conversion of ACTH-(1-39) in brain. It is suggested that they are involved in the modulation of the central activities of ACTH fragments in the brain.

Arginine-vasopressin and oxytocin, peptides which serve as putative precursors for neurotrophic fragments, were digested in the presence of the respective 14C-Tyr2- and 14C-GlyNH29-labeled nonapeptides with a purified synaptic membrane preparation of rat brain. In this preparation aminopeptidase activity predominates in the conversion of these peptides. The disappearance of intact peptide and the release of free 14C-Tyr and 14C-GlyNH2 was followed simultaneously with time by HPLC. Oxytocin was about four times more resistant to proteolysis than arginine-vasopressin as measured by slower disappearance of intact oxytocin, and reflected by the slower release of 14C-Tyr, but not of 14C-GlyNH2 from oxytocin. Comparison of degradation rates of structure analogues showed that peptides having Ile in position 3, as oxytocin, were more resistant than analogues having Phe in position 3, as arginine-vasopressin. The data demonstrate that arginine-vasopressin and oxytocin differ markedly in susceptibility to the aminopeptidase activity in brain synaptic membranes, and indicate that this difference resides primarily in the amino acid residue in position 3. It is suggested that the difference in susceptibility may affect the pattern of neurotrophic metabolites in brain.