Molecular Neurobiology Research Papers - Academia.edu (original) (raw)

The SH-SY5Y cells differentiated by sequential exposure of retinoic acid (RA) and brain-derived neurotrophic growth factor (BDNF) are a well-employed cellular model for studying the mechanistic aspects of neural development and... more

The SH-SY5Y cells differentiated by sequential exposure of retinoic acid (RA) and brain-derived neurotrophic growth factor (BDNF) are a well-employed cellular model for studying the mechanistic aspects of neural development and neurodegeneration. Earlier studies from our lab have identified dramatic upregulation (77 miRNAs) and downregulation (17 miRNAs) of miRNAs in SH-SY5Y cells differentiated with successive exposure of RA + BDNF and demonstrated the essential role of increased levels of P53 proteins in coping with the differentiation-induced changes in protein levels. In continuation to our earlier studies, we have performed unbiased LC-MS/MS global protein profiling of naïve and differentiated SH-SY5Y cells and analyzed the identified proteins in reference to miRNAs identified in our earlier studies to identify the cellular events regulated by both identified miRNAs and proteins. Analysis of LC-MS/MS data has shown a significant increase and decrease in levels of 215 and 163 proteins, respectively, in differentiated SH-SY5Y cells. Integrative analysis of miRNA identified in our previous studies and protein identified in the present study is carried out to discover novel miRNA-protein regulatory modules to elucidate miRNA-protein regulatory relationships of differentiating neurons. In silico network analysis of miRNAs and proteins deregulated upon SH-SY5Y differentiation identified cell cycle, synapse formation, axonogenesis, differentiation, neuron projection, and neurotransmission, as the topmost involved pathways. Further, measuring mitochondrial dynamics and cellular bioenergetics using qPCR and Seahorse XFp Flux Analyzer, respectively, showed that differentiated cells possess increased mitochondrial dynamics and OCR relative to undifferentiated cells. In summary, our studies have identified a novel set of proteins deregulated during neuronal differentiation and establish the role of miRNAs identified in earlier studies in the regulation of proteins identified by LC-MS/MS-based global profiling of differentiating neurons, which will help in future studies related to neural development and neurodegeneration.

Many people worldwide suffer from motor neuron-related disorders such as amyotrophic lateral sclerosis and spinal cord injuries. Recently, several attempts have been made to recruit stem cells to modulate disease progression in ALS and... more

Many people worldwide suffer from motor neuron-related disorders such as amyotrophic lateral sclerosis and spinal cord injuries. Recently, several attempts have been made to recruit stem cells to modulate disease progression in ALS and also regenerate spinal cord injuries. Chorion-derived mesenchymal stem cells (C-MSCs), used to be discarded as postpartum medically waste product, currently represent a class of cells with self renewal property and immunomodulatory capacity. These cells are able to differentiate into mesodermal and nonmesodermal lineages such as neural cells. On the other hand, gelatin, as a simply denatured collagen, is a suitable substrate for cell adhesion and differentiation. It has been shown that electrospinning of scaffolds into fibrous structure better resembles the physiological microenvironment in comparison with two-dimensional (2D) culture system. Since there is no report on potential of human chorion-derived MSCs to differentiate into motor neuron cells i...

Everyday, there are several millions of people that are increasingly unable to combat their frustrating and even fatal romance with getting high and/or experiencing "normal" feelings of well-being. In the USA, the FDA has... more

Everyday, there are several millions of people that are increasingly unable to combat their frustrating and even fatal romance with getting high and/or experiencing "normal" feelings of well-being. In the USA, the FDA has approved pharmaceuticals for drug and alcohol abuse: tobacco and nicotine replacement therapy. The National Institute on Drug Abuse (NIDA) and the National Institute on Alcohol Abuse and Alcoholism (NIAAA) remarkably continue to provide an increasing understanding of the intricate functions of brain reward circuitry through sophisticated neuroimaging and molecular genetic applied technology. Similar work is intensely investigated on a worldwide basis with enhanced clarity and increased interaction between not only individual scientists but across many disciplines. However, while it is universally agreed that dopamine is a major neurotransmitter in terms of reward dependence, there remains controversy regarding how to modulate its role clinically to treat ...

Patients who present with severe intractable apparently idiopathic fatigue accompanied by profound physical and or cognitive disability present a significant therapeutic challenge. The effect of psychological counseling is limited, with... more

Patients who present with severe intractable apparently idiopathic fatigue accompanied by profound physical and or cognitive disability present a significant therapeutic challenge. The effect of psychological counseling is limited, with significant but very slight improvements in psychometric measures of fatigue and disability but no improvement on scientific measures of physical impairment compared to controls. Similarly, exercise regimes either produce significant, but practically unimportant, benefit or provoke symptom exacerbation. Many such patients are afforded the exclusionary, non-specific diagnosis of chronic fatigue syndrome if rudimentary testing fails to discover the cause of their symptoms. More sophisticated investigations often reveal the presence of a range of pathogens capable of establishing life-long infections with sophisticated immune evasion strategies, including Parvoviruses, HHV6, variants of Epstein-Barr, Cytomegalovirus, Mycoplasma, and Borrelia burgdorferi...

Cannabinoids have been proposed as clinically promising neuroprotective molecules, as they are capable to reduce excitotoxicity, calcium influx, and oxidative injury. They are also able to decrease inflammation by acting on glial... more

Cannabinoids have been proposed as clinically promising neuroprotective molecules, as they are capable to reduce excitotoxicity, calcium influx, and oxidative injury. They are also able to decrease inflammation by acting on glial processes that regulate neuronal survival and to restore blood supply to injured area by reducing the vasoconstriction produced by several endothelium-derived factors. Through one or more of these processes, cannabinoids may provide neuroprotection in different neurodegenerative disorders including Parkinson’s disease and Huntington’s chorea, two chronic diseases that are originated as a consequence of the degeneration of specific nuclei of basal ganglia, resulting in a deterioration of the control of movement. Both diseases have been still scarcely explored at the clinical level for a possible application of cannabinoids to delay the progressive degeneration of the basal ganglia. However, the preclinical evidence seems to be solid and promising. There are two key mechanisms involved in the neuroprotection by cannabinoids in experimental models of these two disorders: first, a cannabinoid receptor-independent mechanism aimed at producing a decrease in the oxidative injury and second, an induction/upregulation of cannabinoid CB2 receptors, mainly in reactive microglia, that is capable to regulate the influence of these glial cells on neuronal homeostasis. Considering the relevance of these preclinical data and the lack of efficient neuroprotective strategies in both disorders, we urge the development of further studies that allow that the promising expectatives generated for these molecules progress from the present preclinical evidence till a real clinical application.

Cerebral ischemia/reperfusion (I/R) injury triggers multiple and distinct but overlapping cell signaling pathways, which may lead to cell survival or cell damage. There is overwhelming evidence to suggest that besides necrosis, apoptosis... more

Cerebral ischemia/reperfusion (I/R) injury triggers multiple and distinct but overlapping cell signaling pathways, which may lead to cell survival or cell damage. There is overwhelming evidence to suggest that besides necrosis, apoptosis do contributes significantly to the cell death subsequent to I/R injury. Both extrinsic and intrinsic apoptotic pathways play a vital role, and upon initiation, these pathways recruit downstream apoptotic molecules to execute cell death. Caspases and Bcl-2 family members appear to be crucial in regulating multiple apoptotic cell death pathways initiated during I/R. Similarly, inhibitor of apoptosis family of proteins (IAPs), mitogen-activated protein kinases, and newly identified apoptogenic molecules, like second mitochondrial-activated factor/direct IAP-binding protein with low pI (Smac/Diablo), omi/high-temperature requirement serine protease A2 (Omi/HtrA2), X-linked mammalian inhibitor of apoptosis protein-associated factor 1, and apoptosis-inducing factor, have emerged as potent regulators of cellular apoptotic/antiapoptotic machinery. All instances of cell survival/death mechanisms triggered during I/R are multifaceted and interlinked, which ultimately decide the fate of brain cells. Moreover, apoptotic cross-talk between major subcellular organelles suggests that therapeutic strategies should be optimally directed at multiple targets/mechanisms for better therapeutic outcome. Based on the current knowledge, this review briefly focuses I/R injury-induced multiple mechanisms of apoptosis, involving key apoptotic regulators and their emerging roles in orchestrating cell death programme. In addition, we have also highlighted the role of autophagy in modulating cell survival/death during cerebral ischemia. Furthermore, an attempt has been made to provide an encouraging outlook on emerging therapeutic approaches for cerebral ischemia.

Neuroinflammation, characterized by the appearance of reactive microglial and astroglial cells, is one of the several pathogenic mechanisms of amyotrophic lateral sclerosis (ALS), a fast-progressing and fatal neurodegenerative disease.... more

Neuroinflammation, characterized by the appearance of reactive microglial and astroglial cells, is one of the several pathogenic mechanisms of amyotrophic lateral sclerosis (ALS), a fast-progressing and fatal neurodegenerative disease. Cerebrospinal fluid and spinal cord of ALS patients and SOD1 mutant mice show high concentrations of IL-1β. This interleukin, expressed as an inactive precursor, undergoes a proteolytic maturation by caspase1, whose activation, in turn, depends on inflammasomes. Whether and how inflammasome is activated in ALS models is still to be clarified. The mechanism of inflammasome activation was studied in murine microglial cells overexpressing hSOD1(G93A) and verified in the spinal cord of hSOD1(G93A) mice. Murine microglial hSOD1(G93A) cells express all the inflammasome components and LPS activates caspase1 leading to an increase in the secretion of IL-1β. By activating NF-κB, LPS increases ROS and NO levels that spontaneously react to form peroxynitrite, th...

The importance of the role of the endocannabinoid system (ECS) in neurodegenerative diseases has grown during the past few years. Mostly because of the high density and wide distribution of cannabinoid receptors of the CB1 type in the... more

The importance of the role of the endocannabinoid system (ECS) in neurodegenerative diseases has grown during the past few years. Mostly because of the high density and wide distribution of cannabinoid receptors of the CB1 type in the central nervous system (CNS), much research focused on the function(s) that these receptors might play in pathophysiological conditions. Our current understanding, however, points to much diverse roles for this system. In particular, other elements of the ECS, such as the fatty acid amide hydrolase (FAAH) or the CB2 cannabinoid receptor are now considered as promising pharmacological targets for some diseases and new cannabinoids have been incorporated as therapeutic tools. Although still preliminary, recent reports suggest that the modulation of the ECS may constitute a novel approach for the treatment of Alzheimer’s disease (AD). Data obtained in vitro, as well as in animal models for this disease and in human samples seem to corroborate the notion that the activation of the ECS, through the use of agonists or by enhancing the endogenous cannabinoid tone, may induce beneficial effects on the evolution of this disease.

The cerebral cortex (or neocortex) is a brain structure formed during embryogenesis. The present study seeks to provide a detailed characterization of the Zn homeostatic mechanisms during cerebral cortex formation and development. To... more

The cerebral cortex (or neocortex) is a brain structure formed during embryogenesis. The present study seeks to provide a detailed characterization of the Zn homeostatic mechanisms during cerebral cortex formation and development. To reach that goal, we have combined high-throughput RNA-sequencing analysis of the whole murine genome, X-ray fluorescence nanoimaging (XRF), inductively coupled plasma-atomic emission spectrometry (ICP-AES), and live-cell imaging of dissociated cortical neurons loaded with the Zn fluorescent probe FluoZin-3. The transcriptomic analysis was conducted from mRNAs isolated from cortices collected at embryonic (E) days 11 (E11), E13, and E17 and on postnatal day 1 (PN1) pups. This permitted to characterize the temporal pattern of expression of the main genes participating in the cellular transport, storage, and release of Zn during corticogenesis. It appears that cells of the immature cortex express a wide diversity of actors involved in Zn homeostasis with Zip7, SOD1, and metallothioneins being the most abundant transcripts throughout corticogenesis. The quantification of total Zn with XRF and ICP-AES reveals a reduction of Zn levels. Moreover, this is accompanied by a diminution of the size of the internal pools of mobilizable Zn. This study illustrates the tight temporal and spatial regulation of Zn homeostasis during cerebral brain development.