β3-adrenoceptor impacts apoptosis in cultured cardiomyocytes via activation of PI3K/Akt and p38MAPK / 华中科技大学学报（医学）（英德文版）

β3-adrenoceptor (β3-AR) has been shown to promote myocardial apoptosis. However, the exact physiological role and importance of this receptor in the human myocardium, and its underlying mode of action, have not been fully elucidated. The present study aimed to determine the effects of β3-AR on the promotion of myocardial apoptosis and on norepinephrine (NE) injury. We analyzed NE-induced cardiomyocyte (CM) apoptosis by using a TUNEL and an annexin V/propidium iodide apoptosis assay. Furthermore, we investigated the NE-induced expression of the apoptosis marker genes Akt and p38MAPK, their phosphorylated counterparts p-Akt and p-p38MAPK, caspase-3, Bcl-2, and Bax. In addition, we determined the effect of a 48-h treatment with a β3-AR agonist and antagonist on expression of these marker genes. β3-AR overexpression was found to increase CM apoptosis, accompanied by an increased expression of caspase-3, bax/bcl-2, and p-p38MAPK. In contrast, the β3-blocker reduced apoptosis of CMs and the associated elevated Akt expression. We identified a novel and potent anti-apoptosis mechanism via the PI3K/Akt pathway and a pro-apoptosis pathway mediated by p38MAPK.

β3-adrenoceptor impacts apoptosis in cultured cardiomyocytes via activation of PI3K/Akt and p38MAPK / 华中科技大学学报（医学）（英德文版）

β3-adrenoceptor (β3-AR) has been shown to promote myocardial apoptosis. However, the exact physiological role and importance of this receptor in the human myocardium, and its underlying mode of action, have not been fully elucidated. The present study aimed to determine the effects of β3-AR on the promotion of myocardial apoptosis and on norepinephrine (NE) injury. We analyzed NE-induced cardiomyocyte (CM) apoptosis by using a TUNEL and an annexin V/propidium iodide apoptosis aβsay. Furthermore, we investigated the NE-induced expreβsion of the apoptosis marker genes Akt and p38MAPK, their phosphorylated counterparts p-Akt and p-p38MAPK, caspase-3, Bcl-2, and Bax. In addition, we determined the effect of a 48-h treatment with a β3-AR agonist and antagonist on expression of these marker genes. β3-AR overexpression was found to increase CM apoptosis, accompanied by an increased expression of caspase-3, bax/bcl-2, and p-p38MAPK. In contrast, the β3-blocker reduced apoptosis of CMs and the associated elevated Akt expression. We identified a novel and potent anti-apoptosis mechanism via the PI3K/Akt pathway and a pro-apoptosis pathway mediated by p38MAPK.

Oligomeric interaction between ryanodine receptors: potential role in Ca(2+) release / 生理学报

Receptor proteins in both eukaryotic and prokaryotic cells often form regular lattice or array in the membrane. Recent theoretical analyses indicate that such arrays may provide a novel mechanism for receptor signaling regulation in cells. The functional coupling between neighboring receptors could improve the signaling performance. The ryanodine receptors (RyR)/calcium release channels usually form 2-D regular lattice in the endoplasmic/sarcoplasmic reticulum membranes. Thus, RyR is a potentially good model to study the function of receptor 2-D array. In this article, we briefly review recent progresses in this research field, including RyR-RyR interaction, RyR array's function and working mechanisms. The investigations performed by new methods in our laboratory are summarized. We demonstrate that the RyR-RyR interaction is modulated by the functional states of RyRs. Accordingly, the mechanism of "dynamic coupling" of RyR array is proposed. Its possible role in RyR-mediated Ca(2+) release is discussed.

The inhibitory action of the antisense oligodeoxynucleotide to the expression of vascular endothelial growth factor by radiotherapy in a prostate cancer cell line / 中华男科学杂志

<p><b>OBJECTIVES</b>To investigate mechanism for the increasing level of serum vascular endothelial growth factor(VEGF) in tumour patients during radiotherapy and the inhibitory action of the antisense oligodeoxynucleotide (AS-ODN) to the expression of VEGF protein by radiotherapy in the prostate cancer cell line (PC3M).</p><p><b>METHODS</b>To observe the changes of serum VEGF in the prostate cancer patients during radiotherapy dynamically and the inhibitory action of the antisense oligodeoxynucleotide to the expression of VEGF by radiotherapy in PC3M.</p><p><b>RESULTS</b>The changes of serum VEGF in three patients receiving radiotherapy had been observed continuously. The levels of serum VEGF began to increase when the patients received radiotherapy and rised up to peak value after fifteen days, then declined to the range of pre-radiotherapy. Irradiating the PC3M cells with X-rays significantly increased the VEGF expression and secretion. The expression of VEGF protein in the group treated by VEGF AS-ODNs and X-ray irradiation decreased significantly than the group treated only by X-ray irradiation.</p><p><b>CONCLUSIONS</b>The induction of VEGF protein expression by X-ray irradiation in tumor cells may result in the increasing of the VEGF in the prostate cancer patients during radiotherapy and the induction can be blocked by VEGF AS-ODNs.</p>