Abdullah A

Ravanan P.

Fulltext

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

&nbsp;

&nbsp;

VIT University

Scientific Reports

Neuroblastoma is an embryonic malignancy arises out of the neural crest cells of the sympathetic nervous system. It is the most common childhood tumor and well known for its spontaneous regression via the process of differentiation. The induction of differentiation using small molecule modulators such as all trans retinoic acid is one of the treatment strategies to treat the residual disease. In this study, we have reported the effect of kaempferol, a phytoestrogen in inducing differentiation of neuroblastoma cells in vitro . Treatment of neuroblastoma cells with kaempferol reduced the proliferation and enhanced apoptosis along with the induction of neuritogenesis. Analysis of the expression of neuron specific markers such as β III tubulin, neuron specific enolase and NRDG1 (N-myc down regulated gene 1) revealed the process of differentiation accompanying kaempferol induced apoptosis. Further analysis on understanding the molecular mechanism of action showed that the activity of kaempferol happened through the activation of the endoribonuclease activity of IRE1α (Inositol requiring enzyme 1 alpha), an endoplasmic reticulum (ER) resident transmembrane protein. The in silico docking analysis and biochemical assays using recombinant human IRE1α confirms the binding of kaempferol to the ATP binding site of IRE1α and thereby activating ribonuclease activity. Treatment of cells with the small molecule inhibitor STF083010 which specifically targets and inhibits the endoribonuclease activity of IRE1α showed reduced expression of neuron specific markers and curtailed neuritogenesis. The knock down of IRE1α using plasmid based shRNA lentiviral particles also showed diminished changes in the change in morphology of the cells upon kaempferol treatment. Thus our study suggests that kaempferol induces differentiation of neuroblastoma cells via the IRE1α-XBP1 pathway.

The FEBS Journal

IRE 1α is critical for Kaempferol‐induced neuroblastoma differentiation

Kaempferol mitigates Endoplasmic Reticulum Stress Induced Cell Death by targeting caspase 3/7

Death-Associated Protein Kinase 1 (DAPK1) belongs to a family of five serine/threonine (Ser/Thr) kinases that possess tumor suppressive function and also mediate a wide range of cellular processes, including apoptosis and autophagy. The loss and gain-of–function of DAPK1 is associated with various cancer and neurodegenerative diseases respectively. In recent years, mechanistic studies have broadened our knowledge of the molecular mechanisms involved in DAPK1-mediated autophagy/apoptosis. In the present review, we have discussed the structural information and various cellular functions of DAPK1 in a comprehensive manner. © 2016 Singh, Ravanan and Talwar.

Frontiers in Molecular Neuroscience

Death Associated Protein Kinase 1 (DAPK1): A Regulator of Apoptosis and Autophagy

Execution of fundamental cellular functions demands regulated protein folding homeostasis. Endoplasmic reticulum (ER) is an active organelle existing to implement this function by folding and modifying secretory and membrane proteins. Loss of protein folding homeostasis is central to various diseases and budding evidences suggest ER stress as being a major contributor in the development or pathology of a diseased state besides other cellular stresses. The trigger for diseases may be diverse but, inflammation and/or ER stress may be basic mechanisms increasing the severity or complicating the condition of the disease. Chronic ER stress and activation of the unfolded-protein response (UPR) through endogenous or exogenous insults may result in impaired calcium and redox homeostasis, oxidative stress via protein overload thereby also influencing vital mitochondrial functions. Calcium released from the ER augments the production of mitochondrial Reactive Oxygen Species (ROS).Toxic accumulation of ROS within ER and mitochondria disturbs fundamental organelle functions. Sustained ER stress is known to potentially elicit inflammatory responses via UPR pathways. Additionally, ROS generated through inflammation or mitochondrial dysfunction could accelerate ER malfunction. Dysfunctional UPR pathways have been associated with a wide range of diseases including several neurodegenerative diseases, stroke, metabolic disorders, cancer, inflammatory disease, diabetes mellitus, cardiovascular disease, and others. In this review, we have discussed the UPR signaling pathways, and networking between ER stress-induced inflammatory pathways, oxidative stress, and mitochondrial signaling events, which further induce or exacerbate ER stress. © 2014 Chaudhari, Talwar, Parimisetty, Lefebvre d'Hellencourt and Ravanan.

Frontiers in Cellular Neuroscience

A Molecular Web: Endoplasmic Reticulum Stress, Inflammation, and Oxidative Stress

We explored the effect of a novel synthetic triterpenoid compound cyano enone of methyl boswellates (CEMB) on various prostate cancer and glioma cancer cell lines. CEMB displayed concentration-dependent cytotoxic activity with submicromolar lethal dose 50% (LD50) values in 10 of 10 tumor cell lines tested. CEMB-induced cytotoxicity is accompanied by activation of downstream effector caspases (caspases 3 and 7) and by upstream initiator caspases involved in both the extrinsic (caspase 8) and intrinsic (caspase 9) apoptotic pathways. By using short interfering RNAs (siRNA), we show evidence that knockdown of caspase 8, DR4, Apaf-1, and Bid impairs CEMB-induced cell death. Similar to other proapoptotic synthetic triterpenoid compounds, CEMB-induced apoptosis involved endoplasmic reticulum stress, as shown by partial rescue of tumor cells by siRNA-mediated knockdown of expression of genes involved in the unfolded protein response such as IRE1α, PERK, and ATF6. Altogether, our results suggest that CEMB stimulates several apoptotic pathways in cancer cells, suggesting that this compound should be evaluated further as a potential agent for cancer therapy. ©2011 AACR.

Molecular Cancer Therapeutics

Synthetic Triterpenoid Cyano Enone of Methyl Boswellate Activates Intrinsic, Extrinsic, and Endoplasmic Reticulum Stress Cell Death Pathways in Tumor Cell Lines

Journal	Data powered by TypesetScientific Reports
Publisher	Data powered by TypesetSpringer Science and Business Media LLC
Open Access	Yes