1. Caspase-3, a shrimp phosphorylated hemocytic protein is necessary to control YHV infection
Phattara-Orn Havanapan,Nuanwan Phungthanom,Kallaya Sritunyalucksana,Chartchai Krittanai,Sittiruk Roytrakul,Atchara Paemanee,Suparat Taengchaiyaphum Fish Shellfish Immunol . 2021 Jul;114:36-48. doi: 10.1016/j.fsi.2021.04.007.
By using immunohistochemistry detection, yellow head virus (YHV) was found to replicate in granule-containing hemocytes including semi-granular hemocytes (SGC) and granular hemocytes (GC) during the early phase (24 h post injection) of YHV-infected shrimp. Higher signal of YHV infection was found in GC more than in SGC. Comparative phosphoproteomic profiles between YHV-infected and non-infected GC reveal a number of phosphoproteins with different expression levels. The phosphoprotein spot with later on identified as caspase-3 in YHV-infected GC is most interesting. Blocking caspase-3 function using a specific inhibitor (Ac-DEVD-CMK) demonstrated high replication of YHV and consequently, high shrimp mortality. The immunohistochemistry results confirmed the high viral load in shrimp that caspase-3 activity was blocked. Caspase-3 is regulated through a variety of posttranslational modifications, including phosphorylation. Analysis of phosphorylation sites of shrimp caspase-3 revealed phosphorylation sites at serine residue. Taken together, caspase-3 is a hemocytic protein isolated from shrimp granular hemocytes with a role in anti-YHV response and regulated through the phosphorylation process.
2. Caspase-3 activation in oligodendrocytes from the myelin-deficient rat
J B Grinspan,R Siman,N B Eraydin,L Lavy,J S Beesley J Neurosci Res . 2001 May 15;64(4):371-9. doi: 10.1002/jnr.1088.
The myelin-deficient (MD) rat has a point mutation in its proteolipid protein (PLP) gene that causes severe dysmyelination and oligodendrocyte cell death. Using an in vitro model, we have shown that MD oligodendrocytes initially differentiate similarly to wild-type cells, expressing galactocerebroside, 2',3'-cyclic nucleotide 3'-phosphodiesterase, and myelin basic protein. However, at the time when PLP expression would normally begin, the MD oligodendrocytes die via an apoptotic pathway involving caspase activation. The active form of caspase-3 was detected, along with the cleavage products of poly-(ADP-ribose) polymerase (PARP) and spectrin, major targets of caspase-mediated proteolysis. A specific inhibitor of casapse-3, Ac-DEVD-CMK, reduced apoptosis in MD oligodendrocytes, but the rescued cells did not mature fully or express myelin-oligodendrocyte glycoprotein. These results suggest that mutant PLP affects not only cell death but also oligodendrocyte differentiation.
3. Procaspase-activating compound 1 induces a caspase-3-dependent cell death in cerebellar granule neurons
Øyvind W Akselsen,Gulzeb Aziz,Ragnhild E Paulsen,Trond V Hansen Toxicol Appl Pharmacol . 2010 Sep 15;247(3):238-42. doi: 10.1016/j.taap.2010.07.002.
Procaspase-activating compound 1, PAC-1, has been introduced as a direct activator of procaspase-3 and has been suggested as a therapeutic agent against cancer. Its activation of procaspase-3 is dependent on the chelation of zinc. We have tested PAC-1 and an analogue of PAC-1 as zinc chelators in vitro as well as their ability to activate caspase-3 and induce cell death in chicken cerebellar granule neuron cultures. These neurons are non-dividing, primary cells with normal caspase-3. The results reported herein show that PAC-1 chelates zinc, activates procaspase-3, and leads to caspase-3-dependent cell death in neurons, as the specific caspase-3-inhibitor Ac-DEVD-cmk inhibited both the caspase-3 activity and cell death. Thus, chicken cerebellar granule neurons is a suitable model to study mechanisms of interference with apoptosis of PAC-1 and similar compounds. Furthermore, the present study also raises concern about potential neurotoxicity of PAC-1 if used in cancer therapy.
4. Prediction and validation of apoptosis through cytochrome P450 activation by benzo[a]pyrene
Bibekanand Mallick,Birendra Behera,Niharika Sinha,Sujit K Bhutia,Tapas K Maiti,Prashanta Kumar Panda,Durgesh Nandini Das,Subhadip Mukhopadhyay Chem Biol Interact . 2014 Feb 5;208:8-17. doi: 10.1016/j.cbi.2013.11.005.
Polycyclic aromatic hydrocarbons (PAHs) processed by cytochrome P450 (CYP450) during metabolism is well reported to induce carcinogenesis. The present study has developed a new approach to examine apoptotic activity of a known PAH called benzo[a]pyrene (B[a]P), using protein-ligand and protein-protein interaction through in silico approach, followed by in vitro validation. In silico study showed that the conformational changes and energies involved in the binding of B[a]P to CYP1B1 was crucial with its target proteins. The data showed that activated B[a]P had high affinity to bind with aryl hydrocarbon receptor (AhR) with binding energy of -601.97kcal/mol. Interestingly, B[a]P-CYP1B1 complex showed strong binding affinity for caspase-8, -9, -3 with binding energy of -625.5, -479.3 and -514.2kcal/mol respectively. Moreover, the docking of specific caspase inhibitors in the complex showed weak interaction with low binding energy value as compared to B[a]P-CYP1B1 caspase complexes. To validate our in silico work, we showed B[a]P treated HaCaT cells triggered apoptosis with increase in caspase 8, caspase 9 and caspase 3/7 level. Further, in vitro work confirmed that B[a]P induced apoptosis was significantly suppressed in Ac-DEVD-CMK pre-treated cells. In addition, knockdown of CYP1B1 suppressed B[a]P induced apoptosis in HaCaT cells confirming a pivotal role of CYP1B1 in B[a]P induced apoptosis. Interestingly, through in silico modeling, we screened clotrimazole as a potent CYP1B1 inhibitor which completely inhibited B[a]P mediated activation. This hypothesis was validated by MTT assay, caspase activation measurement and showed remarkable inhibition of B[a]P induced cell death; thereby, highlighting a potent therapeutic role for industrial pollution associated diseases.