PRINCE KUMAR SINGH
Verified @gmail.com
The Hebrew University of Jerusalem
RESEARCH, TEACHING, or OTHER INTERESTS
Neuroscience, Cellular and Molecular Neuroscience, Pharmacology, Toxicology and Pharmaceutics, Cell Biology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Sereen Sandouka, Prince Kumar Singh, Aseel Saadi, Rhoda Olowe Taiwo, Yara Sheeni, Taige Zhang, Larin Deeb, Michelle Guignet, Steve H. White, and Tawfeeq Shekh-Ahmad
Springer Science and Business Media LLC
Abstract Background Epilepsy affects over 65 million people worldwide and significantly burdens patients, caregivers, and society. Drug-resistant epilepsy occurs in approximately 30% of patients and growing evidence indicates that oxidative stress contributes to the development of such epilepsies. Activation of the Nrf2 pathway, which is involved in cellular defense, offers a potential strategy for reducing oxidative stress and epilepsy treatment. Dimethyl fumarate (DMF), an Nrf2 activator, exhibits antioxidant and anti-inflammatory effects and is used to treat multiple sclerosis. Methods The expression of Nrf2 and its related genes in vehicle or DMF treated rats were determined via RT-PCR and Western blot analysis. Neuronal cell death was evaluated by immunohistochemical staining. The effects of DMF in preventing the onset of epilepsy and modifying the disease were investigated in the kainic acid-induced status epilepticus model of temporal lobe epilepsy in rats. The open field, elevated plus maze and T-Maze spontaneous alteration tests were used for behavioral assessments. Results We demonstrate that administration of DMF following status epilepticus increased Nrf2 activity, attenuated status epilepticus-induced neuronal cell death, and decreased seizure frequency and the total number of seizures compared to vehicle-treated animals. Moreover, DMF treatment reversed epilepsy-induced behavioral deficits in the treated rats. Moreover, DMF treatment even when initiated well after the diagnosis of epilepsy, reduced symptomatic seizures long after the drug was eliminated from the body. Conclusions Taken together, these findings suggest that DMF, through the activation of Nrf2, has the potential to serve as a therapeutic target for preventing epileptogenesis and modifying epilepsy.
Sereen Sandouka, Aseel Saadi, Prince Kumar Singh, Rhoda Olowe, and Tawfeeq Shekh-Ahmad
Springer Science and Business Media LLC
Abstract Background Drug resistance is a particular problem in patients with temporal lobe epilepsy, where seizures originate mainly from the hippocampus. Many of these epilepsies are acquired conditions following an insult to the brain such as a prolonged seizure. Such conditions are characterized by pathophysiological mechanisms including massive oxidative stress that synergistically mediate the secondary brain damage, contributing to the development of epilepsy. The transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has emerged in recent years as an attractive therapeutic approach targeting to upregulate the antioxidative defenses in the cell, to ameliorate the oxidative stress-induced damage. Thus, it is important to understand the characteristics of Nrf2 activation during epileptogenesis and epilepsy. Here, we studied the temporal, regional, and cell-type specific expression of Nrf2 in the brain, in a rat model of temporal lobe epilepsy. Results Early after status-epilepticus, Nrf2 is mainly activated in the hippocampus and maintained during the whole period of epileptogenesis. Only transient expression of Nrf2 was observed in the cortex. Nevertheless, the expression of several Nrf2 antioxidant target genes was increased within 24 h after status-epilepticus in both the cortex and the hippocampus. We demonstrated that after status-epilepticus in rats, Nrf2 is predominantly expressed in neurons in the CA1 and CA3 regions of the hippocampus, and only astrocytes in the CA1 increase their Nrf2 expression. Conclusions In conclusion, our data identify previously unrecognized spatial and cell-type dependent activation of Nrf2 during epilepsy development, highlighting the need for a time-controlled, and cell-type specific activation of the Nrf2 pathway for mediating anti-oxidant response after brain insult, to modify the development of epilepsy.
Sereen Sandouka, Aseel Saadi, Rhoda Olowe, Prince Kumar Singh, and Tawfeeq Shekh‐Ahmad
Wiley
The modulation of the nuclear factor erythroid 2‐like 2 (Nrf2) activity has been reported to be implicated in the pathology of various neurological disorders, including epilepsy. Previous studies have demonstrated that Nrf2 is activated in the post‐status epilepticus rat model; however, the spatiotemporal as well as cell type‐specific expression of Nrf2 following brief epileptic seizures remains unclear. Here, we evaluated how an acute epileptic seizure affected the expression of Nrf2 and its downstream genes in the rats' cortex and the hippocampus up to 1 week following the induced seizure. We found that after a pentylenetetrazol‐induced seizure, Nrf2 significantly increased at 24 h at the mRNA level and 3 h at the protein level in the cortex. In the hippocampus, the Nrf2 mRNA level peaked at 3 h after the seizure, and no significant changes were observed in the protein level. Interestingly, the mRNA level of Nrf2 downstream genes peaked at 3–6 h after seizure in both the cortex and the hippocampus. A significant increase in the expression of Nrf2 was observed in the neuronal population of CA1 and CA3 regions of the hippocampus, as well as in the cortex. Moreover, we observed no change in the co‐localization of Nrf2 with astrocytes neither in the cortex nor in CA1 and CA3. Our results revealed that following a brief acute epileptic seizure, the expression of Nrf2 and its downstream genes is transiently increased and peaked at early timepoints after the seizure predominantly in the hippocampus, and this expression is restricted to the neuronal population.
Prince Kumar Singh, Aseel Saadi, Yara Sheeni, and Tawfeeq Shekh-Ahmad
Elsevier BV
Prince Kumar Singh, Jagreeti Singh, Tapas Medhi, and Aditya Kumar
American Chemical Society (ACS)
Diabetes is a group of metabolic disorders characterized by elevated blood sugar levels, leading to many undesirable health consequences. There are many herbal formulations, traditionally used by the Northeast Indian population for disease management. These formulations require scientific validations to optimize their efficacy and increase their popularity. In this study, we attempt to scientifically validate a polyherbal formulation traditionally used for the management of diabetes through preliminary phytochemicals investigation, characterization of potential phytochemicals using Fourier transform infrared (FT-IR) spectroscopy, high-resolution liquid chromatography mass spectrometry (HR-LC/MS) analysis, and in silico characterization of physiochemical, drug-likeness, and pharmacokinetic properties of identified phytochemical compounds. Qualitative phytochemical screening of various extracts of the formulation confirmed the presence of alkaloids, phenols and tannins, flavonoids, fats, and oils. Phytochemical quantification of the various extracts showed that the highest total phenolic content is present in the ethanolic extract (35.61 ± 0.15 mg GAE/g), while the highest total flavonoid content is present in the chloroform extract (76.33 ± 2.96 mg QE/g) of the formulation. FT-IR spectroscopic analysis revealed various characteristic band values with various functional groups in the formulation extract such as amines, alcohol, fluoro compounds, phenol, alkane, alkene, and conjugated acid groups. HR-LC/MS analyses identified nearly 51 compounds including 9 small peptides and 42 potential phytochemical compounds. In silico SwissADME analysis of identified compounds revealed 25 potential compounds following Lipinski’s rule and showing drug-like characteristics, and out of them, 16 compounds exhibited good oral bioavailability, as revealed in the bioavailability radar. The overall study showed that the presented polyherbal formulation is enriched with bio-active phytochemical compounds with good pharmaceutical values.
Aseel Saadi, Sereen Sandouka, Etty Grad, Prince Kumar Singh, and Tawfeeq Shekh-Ahmad
Elsevier BV
Mehraj-U-Din Lone, Javed Miyan, Mohammad Asif, Showkat A. Malik, Parul Dubey, Varsha Singh, Kavita Singh, Kalyan Mitra, Deepali Pandey, Wahajul Haq,et al.
Springer Science and Business Media LLC
Abstract Background The mechanistic (or mammalian) target of rapamycin (mTOR), a Ser/Thr kinase, associates with different subunits forming two functionally distinct complexes, mTORC1 and mTORC2, regulating a diverse set of cellular functions in response to growth factors, cellular energy levels, and nutrients. The mechanisms regulating mTORC1 activity are well characterized; regulation of mTORC2 activity, however, remains obscure. While studies conducted in Dictyostelium suggest a possible role of Ras protein as a potential upstream regulator of mTORC2, definitive studies delineating the underlying molecular mechanisms, particularly in mammalian cells, are still lacking. Methods Protein levels were measured by Western blotting and kinase activity of mTORC2 was analyzed by in vitro kinase assay. In situ Proximity ligation assay (PLA) and co-immunoprecipitation assay was performed to detect protein-protein interaction. Protein localization was investigated by immunofluorescence and subcellular fractionation while cellular function of mTORC2 was assessed by assaying extent of cell migration and invasion. Results Here, we present experimental evidence in support of the role of Ras activation as an upstream regulatory switch governing mTORC2 signaling in mammalian cancer cells. We report that active Ras through its interaction with mSIN1 accounts for mTORC2 activation, while disruption of this interaction by genetic means or via peptide-based competitive hindrance, impedes mTORC2 signaling. Conclusions Our study defines the regulatory role played by Ras during mTORC2 signaling in mammalian cells and highlights the importance of Ras-mSIN1 interaction in the assembly of functionally intact mTORC2.