Cysteine and aspartic proteases possess high elastolytic activity and might contribute to the degradation of the abdominal aortic aneurysm (AAA) wall. The aim of this study was to analyze, in detail, the proteases (cathepsins B, D, K, L and S, and inhibitor cystatin C) found in human AAA and healthy aortic tissue samples. The vessel walls from AAA patients (n=36) and nonaneurysmal aortae (n=10) were retrieved using conventional surgical repair and autopsy methods. Serum samples from the same AAA patients and 10 healthy volunteers were also collected. Quantitative expression analyses were performed at the mRNA level using real-time reverse transcriptase-PCR (RT-PCR). Furthermore, analyses at the protein level included western blot and immunoprecipitation analyses. Cellular sources of cysteine/aspartic proteases and cystatin C were identified by immunohistochemistry (IHC). All cysteine/aspartic proteases and cystatin C were detected in the AAA and control samples. Using quantitative RT-PCR, a significant increase in expression was observed for cathepsins B (P=0.021) and L (P=0.018), compared with the controls. Cathepsin B and cystatin C were also detected in the serum of AAA patients. Using IHC, smooth muscle cells (SMCs) and macrophages were positive for all of the tested cathepsins, as well as cystatin C; in addition, the lymphocytes were mainly positive for cathepsin B, followed by cathepsins D and S. All cysteine/aspartic proteases analyzed in our study were detected in the AAA and healthy aorta. The highest expression was found in macrophages and SMCs. Consequently, cysteine/aspartic proteases might play a substantial role in AAA.
Aged ; Aorta/enzymology ; Aortic Aneurysm, Abdominal/*enzymology ; Aspartic Acid Proteases/genetics/*metabolism ; Case-Control Studies ; Cathepsins/genetics/metabolism ; Cysteine Proteases/genetics/*metabolism ; Humans ; Lymphocytes/enzymology ; Macrophages/enzymology ; Middle Aged ; Myocytes, Smooth Muscle/enzymology ; RNA, Messenger/genetics/metabolism

AIMTo study the incidence of single nucleotide polymorphisms in ubiquitin-specific protease 26 (USP26) gene and its involvement in idiopathic male infertility in China.

METHODSRoutine semen analysis was performed. Infertility factors such as immunological, infectious and biochemical disorders were examined to select patients with idiopathic infertility. DNA was isolated from peripheral blood of the selected patients and control population, which were examined for mutations using polymerase chain reaction-single strand conformation polymorphism analysis. Furthermore, nucleotide sequences were sequenced in some patients and controls.

RESULTSOf 41 infertile men, 9 (22.0%, P = 0.01) had changes in USP26 gene on the X chromosome. A compound mutation (364insACA; 460G right triple arrow A) was detected in 8 patients (19.5%, P = 0.01) and a 1044T right triple arrow A substitution was found in 1 patient (2.4%, P > 0.05). All three variations led to changes in the coding amino acids. Two substitutions predict some changes: 460G right triple arrow A changes a valine into an isoleucine, and 1044T right triple arrow A substitutes a leucine for a phenylalanine. Another insertion of three nucleotides ACA causes an insertion of threonine. No other changes were found in the remaining patients and fertile controls.

CONCLUSIONThe USP26 gene might be of importance in male reproduction. Mutations in this gene might be associated with male infertility, and might negatively affect testicular function. Further research on this issue is in progress.

Asian Continental Ancestry Group ; ethnology ; genetics ; Case-Control Studies ; China ; Cysteine Endopeptidases ; genetics ; metabolism ; Endopeptidases ; genetics ; metabolism ; Humans ; Incidence ; Infertility, Male ; ethnology ; genetics ; Leydig Cells ; metabolism ; Male ; Polymorphism, Single Nucleotide ; genetics ; RNA, Messenger ; genetics ; metabolism ; Sertoli Cells ; metabolism ; Spermatogenesis ; genetics ; Testis ; metabolism ; Ubiquitin-Specific Proteases