2023-03-30·American journal of physiology. Renal physiology
Store-operated Ca2+ entry inhibition ameliorates high glucose and AngⅡ induced podocyte apoptosis and mitochondria damage.
作者: Yu Tao ; Parisa Yazdizadeh Shotorbani ; Denise Inman ; Paromita Das-Earl ; Rong Ma
Hyperglycemia and increased activity of the renal angiotensin II (Ang II) system are two primary pathogenic stimuli for onset and progression of podocyte injury in diabetic nephropathy (DN). However, the underlying mechanisms are not fully understood. Store-operated Ca2+ entry (SOCE) is an important mechanism that helps maintain cell calcium homeostasis in both excitable and non-excitable cells. Our previous study demonstrated that high glucose (HG) enhanced podocyte SOCE. It is also known that Ang II activates SOCE by releasing endoplasmic reticulum Ca2+. However, the role of SOCE in stress-induced podocyte apoptosis and mitochondrial dysfunction remains unclear. The present study was aimed to determine if enhanced SOCE mediated HG and Ang II-induced podocyte apoptosis and mitochondria damage. In kidney from mice with DN, the number of podocytes were reduced significantly. In cultured human podocytes, both HG and Ang II treatment induced podocyte apoptosis, which was significantly blunted by an SOCE inhibitor, BTP2. Seahorse analysis showed that podocyte oxidative phosphorylation in response to HG and Ang II was impaired. This impairment was significantly alleviated by BTP2. The SOCE inhibitor, but not TRPC6 channel inhibitor, significantly blunted the damage of podocyte mitochondrial respiration induced by Ang II treatment. Furthermore, BTP2 reversed impaired mitochondria membrane potential (MMP), ATP production, and enhanced mitochondria superoxide generation induced by HG treatment. Finally, BTP2 prevented overwhelming Ca2+ uptake in HG-treated podocytes. Taken together, our results suggest that enhanced SOCE mediated HG- and Ang II-induced podocyte apoptosis and mitochondria injury.
2023-02-01·Saudi pharmaceutical journal : SPJ : the official publication of the Saudi Pharmaceutical Society
Blockade of store-operated calcium entry sensitizes breast cancer cells to cisplatin therapy via modulating inflammatory response
作者: Alhamed, Abdullah S. ; Alqinyah, Mohammed ; Alsufayan, Musab A. ; Alhaydan, Ibrahim A. ; Alassmrry, Yasseen A. ; Alnefaie, Hajar O. ; Algahtani, Mohammad M. ; Alghaith, Adel F. ; Alhamami, Hussain N. ; Albogami, Abdullah M. ; Alhazzani, Khalid ; Az, Alanazi
Store-operated calcium entry (SOCE) is an important pathway for calcium signaling that regulates calcium influx across the plasma membrane upon the depletion of calcium stores in the endoplasmic reticulum. SOCE participates in regulating a number of physiological processes including cell proliferation and migration while SOCE dysregulation has been linked with pathophysiological conditions such as inflammation and cancer. The crosslink between cancer and inflammation has been well-established where abundant evidence demonstrate that inflammation plays a role in cancer pathophysiology and the response of cancer cells to chemotherapeutic agents including cisplatin. Indeed, the efficacy of cisplatin against cancer cells is reduced by inflammation. Interestingly, it was shown that SOCE enhances inflammatory signaling in immune cells. Therefore, the main objectives of this study are to examine the impact of SOCE inhibition on the cisplatin sensitivity of breast cancer cells and to explore its related mechanism in modulating the inflammatory response in breast cancer cells. Our findings showed that SOCE inhibitor (BTP2) enhanced cisplatin cytotoxicity against resistant breast cancer cells via inhibition of cell proliferation and migration as well as induction of apoptosis. We also found an upregulation in the gene expression of two major components of SOCE, STIM1 and ORAI1, in cisplatin-resistant breast cancer cells compared to cisplatin-sensitive breast cancer cells. In addition, cisplatin treatment increased the gene expression of STIM1 and ORAI1 in cisplatin-resistant breast cancer cells. Finally, this study also demonstrated that cisplatin therapy caused an increase in the gene expression of inflammatory mediators COX2, IL-8, and TNF-α as well as COX2 protein and upon SOCE inhibition using BTP2, the effect of cisplatin on the inflammatory mediators was reversed. Altogether, this study has proven the pivotal role of SOCE in cisplatin resistance of breast cancer cells and showed the importance of targeting this pathway in improving breast cancer therapy.
2022-09-05·The Journal of general physiology2区 · 医学
Emergent role of SARAF and store-operated Ca2+ entry in angiogenesis.
2区 · 医学
作者: Isabel María Galeano-Otero ; Raquel Del Toro ; Tarik Smani
Angiogenesis is a multistep process that controls endothelial cell (EC) functioning to form new blood vessels from preexisting vascular beds. This process is tightly regulated by pro-angiogenic factors, such as vascular endothelial growth factor (VEGF), which promotes signaling pathways involving the increase in the intracellular Ca2+ concentration ([Ca2+]i). Recent evidence suggests that store-operated Ca2+ entry (SOCE) might play a role in angiogenesis. However, little is known regarding the role of SARAF, SOCE-associated regulatory factor in this process. The aim of this study is to examine the role of SARAF in angiogenesis. In vitro angiogenesis was studied using human umbilical endothelial cells (HUVECs) for tube formation assay and vessel sprouting using rat aortic ring by Matrigel assay supplemented with endothelial cell basal medium enriched with different growth factors (VEGF, FGF, b-EGF, and IGF). HUVECs migration was evaluated by wound healing assay, and HUVECs proliferation using Ki67+ marker. Ex vivo angiogenesis was examined by whole mount mice retina on P6 in neonatal mice injected with increasing concentrations of a SOCE inhibitor, GSK-7975A, on P3, P4, and P5. We observed that SOCE inhibition with GSK-7975A blocks aorta sprouting, as well as HUVEC tube formation and migration. The intraperitoneal injection of GSK-7975A also delays the development of retinal vasculature assessed at postnatal day 6 in mice since it reduces vessel length and the number of junctions while it increases lacunarity. Moreover, we found that knockdown of SARAF using siRNA impairs VEGF-mediated [Ca2+]i increase and HUVEC tube formation, proliferation, and migration. Our data show for the first that SOCE inhibition prevents angiogenesis using different approaches and we provide evidence indicating that SARAF plays a critical role in angiogenesis.