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Phyto-Nano Interaction
Published in Ramesh Raliya, Nanoscale Engineering in Agricultural Management, 2019
Divya Vishambhar Kumbhakar, Debadrito Das, Bapi Ghosh, Ankita Pramanik, Sudha Gupta, Animesh Kumar Datta
Elevated ROS generation due to phyto-nano interaction causes cell cycle dysregulation, resulting in cell granularity and shrinkage of the cell at an early phase of apoptosis (Vamanu et al. 2008, Faisal et al. 2013) leading to enhanced cell mortality. Cell cycle checkpoints (the G1/S checkpoint and the G2/M checkpoint) are used to examine and regulate cell cycle progression, which is either altered or inhibited in NPs treatments. Mahmoudi et al. (2011) revealed that apoptotic cells due to NP exposure may be the outcome of failure in separation of condensed chromosomes in mitotic progression. Flow cytometric analysis confirmed that NPs are capable of inducing sub-G1 apoptotic peak (different amounts of DNA lost in form of fragments) or G2/M arrest (Chunyan and Valiyaveettil 2013) in host seedlings in relation to controls (Fig. 5). Such events are activated by the caspase-3 protease pathway of signal transduction (Green 1998, Eom and Choi 2010, Li and Xing 2011, Faisal et al. 2013).
Evaluating the Interactions of Silver Nanoparticles and Mammalian Cells Based on Biomics Technologies
Published in Huiliang Cao, Silver Nanoparticles for Antibacterial Devices, 2017
The ‘MAPK signalling pathway’ plays vital roles in cell apoptosis regulation. Down-regulated CRK can lead to JNK-mediated apoptotic response (Hrincius et al. 2010). HSPA5 is a member of the heat shock protein 70 (HSP70) family, and its high expression may accelerate Ca2+ binding, resist calcium signalling and then prevent the activation of some pro-apoptotic proteins (Zimmermann et al. 2010). On the contrary, down-regulation of HSPA5 will be beneficial for inducing apoptosis. Caspase-3 (CASP3) gene-encoded protein plays a primary role in the execution phase of cell apoptosis, is up-regulated in apoptotic cells through extrinsic and intrinsic pathways (Ghavami et al. 2009), and has been considered as a reliable marker of apoptosis (Duan et al. 2003). Dual-specificity phosphatase 5 (DUSP5) could be invoked by the p53 protein, which was up-regulated in response to cellular stress and could evoke apoptosis (Ueda et al. 2003). Thus, the down-regulation of CRK and HSPA5 and the up-regulation of CASP3 and DUSP5 might imply that Ag NPs can cause apoptosis.
Analysis of Single Cells Using Lab-on-a-Chip Systems
Published in Frances S. Ligler, Jason S. Kim, The Microflow Cytometer, 2019
In addition to changes in the cell membrane, apoptosis involves the active participation of endogenous cellular enzymes. A family of cysteine proteases (caspases) seems to represent the effector arm of the apoptotic program. Caspase-3 is a key protease that is activated during the early stages of apoptosis and is synthesized as an inactive proenzyme. It is cleaved and thereby activated in cells undergoing apoptosis. The expression of active caspase-3 can be studied in apoptotic cells by staining the cells intracellularly with antibodies.
Estimation of silver nanoparticles effect on the reproductive health of female Wistar rats
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Yara Mohamed, Abdel-Wahab El Ghareeb, Fawzy Ali Attaby, Heba Ali Abd El-Rahman
Caspases play an important role in the apoptosis process. Caspase-3 is a commonly activated death protease that catalyses the precise cleavage of various important cellular proteins. Caspases-3 activation pathways have been identified that are dependent on or independent of mitochondrial cytochrome c release and caspase-9 activity. Caspase-3 is required for appropriate brain development and other apoptotic pathways in tissue-cell-type-and death stimulus-specific ways, including chromatin condensation and DNA fragmentation, in all cell types studied. So, whereas caspase-3 is important for certain processes linked to cell disassembly and the formation of apoptotic bodies, it may also be active prior to or during the decision to lose cell viability [47]. Our results showed a significant increase in caspase-3 expression after AgNPs injection in ovarian and uterine tissues. These results were inconsistent with Cu NP exposure which induced the expression of caspase-9 and caspase-3 levels [45]. Another study on the uterus showed that the expression of caspases 3, 8, and 9 increased after exposure to Cu-NP in the treated rat uterus [31]. Also, El-Nouri et al. stated that there were positive reactions for Caspase 3, indicating apoptosis [42]. AgNPs cause apoptosis in the ovaries and uterus, according to our findings, by inducing oxidative stress and activation of the caspase-3 pathway.
Characterization of green synthesized flaxseed zinc oxide nanoparticles and their cytotoxic, apoptotic and antimigratory activities on aggressive human cancer cells
Published in Inorganic and Nano-Metal Chemistry, 2021
Suray Pehlivanoglu, Cigdem Aydin Acar, Soner Donmez
The caspase activation of A549, HT29, and MDA-MB-231 cells were evaluated under 10, 25, 50 μg/mL concentrations of the ZnO NPs for 48 h. Colorimetric ELISA assays showed that the caspase-3 and −9 activities significantly increased (p > 0.05) in treated cells compare to control. The NPs induced 2.5–3.1-fold caspase-3 and 3.5–4.15-fold caspase-9 activation. Contrary to this, the treated cells did not show any statistically significant caspase-8 activation (Figure 6). The enhanced caspase-3/9 activations in treated cells inferred intrinsic apoptotic pathway. Caspase-3 is the most important apoptotic executioner caspase because it activates death proteases and catalyzes the autoproteolytic cleavage of cellular structures. Caspase-3 can be directly activated by initiator caspases, such as caspase-8 (extrinsic pathway) and caspase-9 (intrinsic pathway).[48,49] Consequently, it could be said that the toxicity of the green synthesized ZnO NPs was associated with proapoptotic activity through the induction of caspase-3/9 activation.
Combined treatment with auranofin and trametinib induces synergistic apoptosis in breast cancer cells
Published in Journal of Toxicology and Environmental Health, Part A, 2021
Min-Kyung Joo, Sangyun Shin, Dong-Jin Ye, Hong-Gyu An, Tae-Uk Kwon, Hyoung-Seok Baek, Yeo-Jung Kwon, Young-Jin Chun
To investigate altered apoptotic signaling initiated by the synergistic effect on cell growth inhibition, changes in caspase-3/7 activation and PARP cleavage were determined. Combination of auranofin (0.125 μM) with trametinib (7.5 μM) was found to significantly elevate the activity of caspase-3/7 by 71.7% in MCF-7 cells. Following combination exposures, our findings demonstrated significantly enhanced caspase-3/7 activation compared to individual treatments (Figure 3a). In MDA-MB-231 cells, combination with auranofin (0.15 μM) and trametinib (0.5 μM) also showed increases of caspase-3/7 activity (Supplementary Figure 2C). An increase in cleaved caspase 3 is one of the major phenomena occurring in cancer cell apoptosis (Yang et al. 2001). Although expression of caspase 3 is known to relatively low in MCF-7 cells compared to other cancer cells (Ghate et al. 2013; Wesierska-Gadek et al. 2011), our data demonstrated that combination treatment with auranofin and trametinib induced cleavage of caspase 3 in MCF-7 cells (Figure 3b). As illustrated in Figure 3c, combination incubation with auranofin and trametinib resulted in a marked rise in PARP cleavage.