Rat KalliKrein 1 ELISA Kit

The sera of patients with breast cancer have higher levels of des[Arg(9)]bradykinin, a kinin B-1 receptor (B1R) agonist, than that from healthy individuals. Stimulation of breast cancer cells with the analog Lys des[Arg(9)]bradykinin causes release of metalloproteinases-2 and -9 and increases cell proliferation. We examined the possibility that breast cancer cells, in addition to B1R, express the kinin-forming protease true tissue kallikrein (KLK1) and the endogenous proteins termed kininogens from which kinins are enzymatically released. Furthermore, we investigated whether stimulation of breast cancer cells with a B1R agonist would modify the cellular levels of KLK6, KLK10 and KLK11, three kallikrein-related peptidases with a still poorly-understood biological role in breast cancer. We found that breast cancer cells expressed KLK1 and kininogens, and that stimulation of estrogen-sensitive breast cancer cells with the B1R agonist produced down-regulation of KLK10 (a protease associated with growth suppression) but up-regulation of KLK11 and KLK6 (peptidases related to increased cell proliferation and invasiveness, respectively). Furthermore, we showed that the B1R agonist acts as a functional stimulus for the secretion of KLK1 and KLK6, an event relevant for kinin production and cell invasion, respectively.

OBJECTIVES To investigate the effect of kallikrein-related peptidase KLK1 on azoospermic mice induced by busulfan and mouse spermatogonial stem cell. METHODS Mice were treated with a single intraperitoneal injection of busulfan, and 4 weeks later, they received a daily intraperitoneal injection of KLK1 at different doses for another 4 weeks. Eight weeks after the busulfan treatment, all mice were sacrificed and their testes were collected for histological evaluation, immunostaining and protein extraction. In vitro, immortalized mouse spermatogonial stem cells, namely C18-4 cells, were treated with KLK1 for proliferation assays. RESULTS Histological evaluation of testes, epididymis and epididymal fluid showed that KLK1-treated mice had better spermatogenesis than the control group. Immunostaining showed that tissue samples from testes of KLK1-treated mice had more PLZF- and SCP3-positive cells per seminiferous tubule as well as more PNA-positive cells in the seminiferous tubules. Western blots revealed higher expression levels of PCNA in KLK1-treated mice than in control mice. C18-4 cells treated with KLK1 had a higher proliferation rate and higher expression levels of PCNA, Cyclin A and Cyclin E, and the level of phosphorylated ERK2 were increased after KLK1 treatment. CONCLUSION Collectively, KLK1 can improve spermatogenesis in azoospermic mice, and KLK1 can promote the proliferation of mouse spermatogonial stem cells via activating ERK1/2 and cell cycle proteins Cyclin A and Cyclin E. This study could offer novel approach and provide new targets for the treatment of azoospermia. (C) 2018 Published by Elsevier Inc.