Stereotactic Body Radiotherapy and Conventional Radiotherapy Induce Cytoskeleton Extension and Enlargement of Cell Morphology in Non-Small Cell Lung Cancer

Stereotactic body radiotherapy (SBRT) is now widely used in cancer therapy. However, the biological effects of SBRT compared with conventional radiotherapy (CRT) are not clear. The cytoskeleton plays an important role in many biological processes and cellular life activities. The effects of SBRT or CRT on the morphology and cytoskeletal structure of non-small cell lung cancer (NSCLC) cells remain unknown. Based on the biologically equivalent dose (BED) formula, we designed SBRT and CRT fractionation regimens with the same BED. The morphology was captured during radiation, and rhodamine-phalloidin immunofluorescence was used to study the cytoskeleton. A lactate dehydrogenase assay kit was used to determine the cell membrane permeability, and western blot was used to detect the cytoskeleton protein expression levels. The morphology and cytoskeleton expanded after SBRT or CRT, with an increase in cell membrane permeability and stable cytoskeleton protein levels. Besides, different dose of SBRT (10,20,30 Gy) induce similar morphology and cytoskeleton enlargement. Our findings indicate that SBRT and CRT can induce cytoskeleton reorganization and the enlargement of cell morphology (at different rates) in NSCLC. The morphology and cytoskeleton enlargement after SBRT are dose independence.

CcrZ is a pneumococcal spatiotemporal cell cycle regulator that interacts with FtsZ and controls DNA replication by modulating the activity of DnaA

Most bacteria replicate and segregate their DNA concomitantly while growing, before cell division takes place. How bacteria synchronize these different cell cycle events to ensure faithful chromosome inheritance by daughter cells is poorly understood. Here, we identify Cell Cycle Regulator protein interacting with FtsZ (CcrZ) as a conserved and essential protein in pneumococci and related Firmicutes such as Bacillus subtilis and Staphylococcus aureus. CcrZ couples cell division with DNA replication by controlling the activity of the master initiator of DNA replication, DnaA. The absence of CcrZ causes mis-timed and reduced initiation of DNA replication, which subsequently results in aberrant cell division. We show that CcrZ from Streptococcus pneumoniae interacts directly with the cytoskeleton protein FtsZ, which places CcrZ in the middle of the newborn cell where the DnaA-bound origin is positioned. This work uncovers a mechanism for control of the bacterial cell cycle in which CcrZ controls DnaA activity to ensure that the chromosome is replicated at the right time during the cell cycle.

Rapamycin Attenuated Podocyte Apoptosis Via Upregulation of Nestin in Ang II-Induced Podocyte Injury

Background: Angiotensin II (Ang II) contributes to the progression of glomerulosclerosis mainly by inducing podocyte injury. Convincing evidence indicates that the mTOR inhibitor rapamycin plays a fundamental role in the protection of podocyte injury. Nestin, a major cytoskeleton protein, is expressed stably in podocytes and correlates with podocyte damage. The purpose of this study was to investigate the effect of rapamycin in podocyte injury induced by Ang II, and clarify the role and mechanism of Nestin in the protection of podocyte injury.Methods and Results: We established an Ang II perfusion animal model, and the effects of interfere treatment of rapamycin on podocyte were detected in vivo. In vitro, podocytes were stimulated with Ang II and rapamycin to observe podocyte injury, nestin-siRNA was transfected to investigate the mechanism in the process. We observed that Ang II induce podocyte injury both in vivo and in vitro, while rapamycin treatment relieved Ang II-induced podocyte injury. Also we found that nestin co-localized with p-mTOR in glomeruli, and the protection effect of rapamycin was reduced by nestin-siRNA in podocytes. Moreover, co-IP indicated the interaction between nestin and p-mTOR, and nestin could affect podocyte injury via mTOR/P70S6K signaling pathway.Conlusion: Thus, here, we demonstrated that Rapamycin attenuated podocyte apoptosis via upregulation of nestin through mTOR/P70S6K signsling pathway in Ang II-induced podocyte injury.

Diseases associated with mutations in the filamin A gene (FLNA)

The article presents literature review of the diseases associated with mutations in the FLNA gene encoding filamin A, which is a cytoskeleton protein with polymorphic functions. The mutations of this gene lead to the damage of the central nervous system (periventricular nodular heterotopy), respiratory organs (emphysema, interstitial lung disease), heart (congenital heart defects and minor heart abnormalities); the listed diseases can be diagnosed at different ages. The information presented in this review can be useful for clinical geneticists, specialists in rare (orphan) diseases, pediatricians, neonatologists, neurologists, epileptologists, pulmonologists, surgeons, cardiologists for timely diagnosis and improvement of medical care for patients requiring a multidisciplinary approach.

Involvement of Acid-Sensing Ion Channel 1a Contribute to The Effect of Extracellular Acidosis on Vascular Endothelialcell Damage of Henoch-Schönlein Purpura Patients

Introduction: Henoch-Schönlein purpura (HSP) is a common kind of systematic vasculitis in children characterized by rash, joint pain,abdominal symptoms and renal disease,the detail pathogenesis of HSP has not been elucidated.Acid-sensing ion channels (ASICs) is a proton-gated sodium selective channel that belongs to Degenerin /epithelial Sodium Channel(DEG/ENaC) superfamily,previous research found the expression of ASIC1a in vascular endothellial cells could be stimulated by serum IgA1 from HSP patients under acidic environment.This study aims to investigate the molecular mechanisms of silencing of acid-sensing ion channel 1a(ASIC1a) protects the vascular endothelial cells from Henoch-Schonlein purpura(HSP) patients.Methods:Human dermal microvascular endothelial cells ( HDMVEC) were cultured in vitro，siRNA sequences were designed for the coding region of human ASIC1a gene and HDMVEC cells were transfected with recombinant lentivirus( LV) -sh-ASIC1a． The control group ( NC group) without virus transfection and LV-sh-ASIC1a transfection group ( si-ASIC1a group) were set up． The expression of transfixed ASIC1a gene was detected by RT-PCR． After virus transfection 72 h，serum IgA1from HSP patients and serum IgA1 of normal children were added into HDMVEC cells． ASIC1a and cytoskeleton protein ( sm-α f-actin，MLCK) mRNA and protein expressions were detected by real-time PCR and Western blotting Methods.The binding activity of NF- κB with DNA in HDMVEC was determined by electrophoretic mobility shift assay (EMSA).The whole-cell patch-clamp technique was used to record the current changes and electrophysiological characteristics of ASICs and calcium in HDMVEC.Results：Cytoskeleton protein ( sm-α f-actin，MLCK) mRNA and protein expressions in the group of si-ASIC1a group were significantly increased compared with the NC control group( P ＜ 0． 01) ．The HSP serum and silencing of ASIC1a had no significant effect on the binding activity of NF-κB with DNA in HDMVEC. Compared with the NC control group, the ASICS current and calcium overload of the si-ASIC1A group were reduced( P ＜ 0． 01) ．Conclusion: Silencing ASIC1a can protect HSP vascular endothelial cell injury by inhibiting ASIC1-related calcium influx and reducing the overload of calcium ,not the NF- κB signaling pathway.

Involvement of Acid-Sensing Ion Channel 1a Contribute to The Effect of Extracellular Acidosis on Vascular Endothelialcell Damage of Henoch-Schönlein Purpura Patients

Background: Henoch-Schönlein purpura (HSP) is a common kind of systematic vasculitis in children characterized by rash, joint pain,abdominal symptoms and renal disease,the detail pathogenesis of HSP has not been elucidated.Acid-sensing ion channels (ASICs) is a proton-gated sodium selective channel that belongs to Degenerin /epithelial Sodium Channel(DEG/ENaC) superfamily,previous research found the expressions of ASIC1a and ASIC3 in the vascular endothelial cells of HSPThis study aims to investigate the molecular mechanisms of silencing of acid-sensing ion channel 1a(ASIC1a) protects the vascular endothelial cells from Henoch-Schonlein purpura(HSP) patients.Findings:Human dermal microvascular endothelial cells ( HDMVEC) were cultured in vitro, siRNA sequences were designed for the coding region of human ASIC1a gene and HDMVEC cells were transfected with recombinant lentivirus( LV) -sh-ASIC1a. The control group ( NC group) without virus transfection and LV-sh-ASIC1a transfection group ( si-ASIC1a group) were set up. The expression of transfixed ASIC1a gene was detected by RT-PCR. After virus transfection 72 h, serum IgA1from HSP patients and serum IgA1 of normal children were added into HDMVEC cells. ASIC1a and cytoskeleton protein ( sm-α f-actin, MLCK) mRNA and protein expressions were detected by real-time PCR and Western blotting Methods.The binding activity of NF- κB with DNA in HDMVEC was determined by electrophoretic mobility shift assay (EMSA).The whole-cell patch-clamp technique was used to record the current changes and electrophysiological characteristics of ASICs in HDMVEC.Cytoskeleton protein ( sm-α f-actin, MLCK) mRNA and protein expressions in the group of si-ASIC1a group were significantly increased compared with the NC control group( P＜0.01). The HSP serum and silencing of ASIC1a had no significant effect on the binding activity of NF-κB with DNA in HDMVEC. Compared with the NC control group, the ASICS current and calcium overload of the si-ASIC1A group were reduced( P＜0.01) ．Conclusions: Silencing ASIC1a can protect HSP vascular endothelial cell injury by inhibiting ASIC1-related calcium influx and reducing the overload of calcium ,not the NF- κB signaling pathway.

Neuronal death in pneumococcal meningitis is triggered by pneumolysin and pilus-1 interactions with β-actin

Neuronal damage is a major consequence of bacterial meningitis, but little is known about mechanisms that lead to neuronal death. Streptococcus pneumoniae (pneumococcus) is a leading cause of bacterial meningitis and many survivors develop neurological sequelae after the acute infection has resolved, possibly due to neuronal damage. Here, we studied mechanisms for pneumococcal interactions with neurons. Using human primary neurons and co-immunoprecipitation assays, we showed that pneumococci interact with the cytoskeleton protein β-actin through the pilus-1 adhesin RrgA and the cytotoxin pneumolysin (Ply), thereby promoting adhesion and uptake into neurons and neuronal death. Using our bacteremia-derived meningitis mouse model, we observed that RrgA- and Ply-expressing pneumococci co-localize with neuronal β-actin. We found that pneumococcal-infected neurons show increased intracellular Ca2+ levels depending on RrgA and mainly Ply which likely cause actin cytoskeleton disassembly leading to neuronal damage. Finally, neuronal death caused by pneumococcal infection could be inhibited using antibody against β-actin.