Explore the vast range of titles available.

Tauopathies are a class of neurodegenerative disorders characterized by abnormal deposition of post-translationally modified tau protein in the human brain. Tauopathies are associated with Alzheimer's disease (AD), chronic traumatic encephalopathy (CTE), and other diseases. Hyperphosphorylation increases tau tendency to aggregate and form neurofibrillary tangles (NFT), a pathological hallmark of AD. In this study, okadaic acid (OA, 100 nM), a protein phosphatase 1/2A inhibitor, was treated for 24h in mouse neuroblastoma (N2a) and differentiated rat primary neuronal cortical cell cultures (CTX) to induce tau-hyperphosphorylation and oligomerization as a cell-based tauopathy model. Following the treatments, the effectiveness of different kinase inhibitors was assessed using the tauopathy-relevant tau antibodies through tau-immunoblotting, including the sites: pSer202/pThr205 (AT8), pThr181 (AT270), pSer202 (CP13), pSer396/pSer404 (PHF-1), and pThr231 (RZ3). OA-treated samples induced tau phosphorylation and oligomerization at all tested epitopes, forming a monomeric band (46-67 kDa) and oligomeric bands (170 kDa and 240 kDa). We found that TBB (a casein kinase II inhibitor), AR and LiCl (GSK-3 inhibitors), cyclosporin A (calcineurin inhibitor), and Saracatinib (Fyn kinase inhibitor) caused robust inhibition of OA-induced monomeric and oligomeric p-tau in both N2a and CTX culture. Additionally, a cyclin-dependent kinase 5 inhibitor (Roscovitine) and a calcium chelator (EGTA) showed contrasting results between the two neuronal cultures. This study provides a comprehensive view of potential drug candidates (TBB, CsA, AR, and Saracatinib), and their efficacy against tau hyperphosphorylation and oligomerization processes. These findings warrant further experimentation, possibly including animal models of tauopathies, which may provide a putative Neurotherapy for AD, CTE, and other forms of tauopathy-induced neurodegenerative diseases.

Alzheimer’s disease (AD), the leading cause of dementia worldwide, remains a challenge due to its complex origin and degenerative character. The need for accurate biomarkers and treatment targets hinders early identification and intervention. To fill this gap, we used a novel longitudinal proteome methodology to examine the temporal development of molecular alterations in the cortex of an intracerebroventricular streptozotocin (ICV-STZ)-induced AD mouse model for disease initiation and progression at one, three-, and six-weeks post-treatment. Week 1 revealed metabolic protein downregulation, such as Aldoa and Pgk1. Week 3 showed increased Synapsin-1, and week 6 showed cytoskeletal protein alterations like Vimentin. The biological pathways, upstream regulators, and functional effects of proteome alterations were dissected using advanced bioinformatics methods, including Ingenuity Pathway Analysis (IPA) and machine learning algorithms. We identified Mitochondrial Dysfunction, Synaptic Vesicle Pathway, and Neuroinflammation Signaling as disease-causing pathways. Huntington’s Disease Signaling and Synaptogenesis Signaling were stimulated while Glutamate Receptor and Calcium Signaling were repressed. IPA also found molecular connections between PPARGC1B and AGT, which are involved in myelination and possible neoplastic processes, and MTOR and AR, which imply mechanistic involvements beyond neurodegeneration. These results help us comprehend AD’s molecular foundation and demonstrate the promise of focused proteomic techniques to uncover new biomarkers and therapeutic targets for AD, enabling personalized medicine.

The DUF668 gene performs a critical role in mitigating the impact of abiotic stress factors. In this study, we identified 30 DUF668 genes in a soybean genome, distributed across fifteen chromosomes. The phylogenetic analysis classified the DUF668 genes into three groups (group I, group II, and group III). Interestingly, gene structure analysis illustrated that several GmDUF668 genes were without introns. Furthermore, the subcellular localization results suggested that GmDUF668 proteins were present in the nucleus, mitochondria, cytoplasm, and plasma membrane. GmDUF668 promoters were analyzed in silico to gain insight into the presence of regulatory sequences for TFs binding. The expression profiling illustrated that GmDUF668 genes showed expression in leaves, roots, nodules, and flowers. To investigate their response to salt stress, we utilized the RNA sequencing data of GmDUF668 genes. The results unveiled that GmDUF668-8, GmDUF668-20, and GmDUF668-30 genes were upregulated against salt stress treatment. We further validated these findings using qRT-PCR analysis. These findings provide a scientific basis to explore the functions of GmDUF668 genes against different stress conditions.

Tauopathy is a class of a neurodegenerative disorder linked with tau hyperphosphorylation, proteolysis, and aggregation. Tau can be subjected to proteolysis upon calpain activation in Alzheimer disease (AD), and traumatic brain injury (TBI). We and others have extensively researched calpain-mediated tau breakdown products (Tau-BDP; 45K, 35K, and 17K). Tau proteolysis might also generate low molecular weight (LMW ≤10K) proteolytic peptides after neurodegenerative damage. In this study, we have subjected purified tau protein (phospho and non-phospho) and mouse brain lysate to calpain-1 digestion to characterize the LMW generated by nano-liquid chromatography coupled to electrospray ionization to tandem mass spectrometry (nano-LC-ESI-MS/MS). We have also challenged differentiated primary cerebrocortical neuronal cultures (CTX) with neurotoxic agents (calcium ionophore calcimycin (A23187), staurosporine (STS), N-methyl-D-aspartate (NMDA), and Maitotoxin (MTX)) that mimic neurodegeneration to investigate the peptidome released into the conditioned cell media. We used a simple workflow in which we fractionate LMW calpain-mediated tau peptides by ultrafiltration (molecular weight cut-off value (MWCO) of 10K) and subject filtrate fractions to nano-LC-MS/MS analysis. The high molecular weight (HMW) peptides and intact proteins retained on the filter were analyzed separately by western blotting using total and phospho-specific tau antibodies. We have identified several novel proteolytic tau peptides (phosphorylated and non-phosphorylated) that are only present in samples treated with calpain or cell-based calpain activation model (particularly N- and C-terminal peptides). Our findings can help in developing future research strategies emphasizing on the suppression of tau proteolysis as a target.

The DUF668 gene performs a critical role in mitigating the impact of abiotic stress factors. In this study, we identified 30 DUF668 genes in a soybean genome, distributed across fifteen chromosomes. The phylogenetic analysis classified the DUF668 genes into three groups (group I, group II, and group III). Interestingly, gene structure analysis illustrated that several GmDUF668 genes were without introns. Furthermore, the subcellular localization results suggested that GmDUF668 proteins were present in the nucleus, mitochondria, cytoplasm, and plasma membrane. GmDUF668 promoters were analyzed in silico to gain insight into the presence of regulatory sequences for TFs binding. The expression profiling illustrated that GmDUF668 genes showed expression in leaves, roots, nodules, and flowers. To investigate their response to salt stress, we utilized the RNA sequencing data of GmDUF668 genes. The results unveiled that GmDUF668-8, GmDUF668-20, and GmDUF668-30 genes were upregulated against salt stress treatment. We further validated these findings using qRT-PCR analysis. These findings provide a scientific basis to explore the functions of GmDUF668 genes against different stress conditions.

Traumatic brain injury (TBI) is a multidimensional damage, and currently, no FDA-approved medicine is available. Multiple pathways in the cell are triggered through a head injury (e.g., calpain and caspase activation), which truncate tau and generate variable fragment sizes (MW 400–45,000 K). In this study, we used an open-head TBI mouse model generated by controlled cortical impact (CCI) and collected ipsilateral (IC) and contralateral (CC) mice htau brain cortices at one (D1) three (D3), and seven (D7) days post-injury. We implemented immunological (antibody-based detection) and peptidomic approaches (nano-reversed-phase liquid chromatography/tandem mass spectrometry) to investigate proteolytic tau peptidome (low molecular weight (LMW) < 10 K)) and pathological phosphorylation sites (high-molecular-weight (HMW); > 10 K) derived from CCI-TBI animal models. Our immunoblotting analysis verified tau hyperphosphorylation, HMW, and HMW breakdown products (HMW-BDP) formation of tau (e.g., pSer 202 , pThr 181 , pThr 231 , pSer 396 , and pSer 404 ), following CCI-TBI. Peptidomic data revealed unique sequences of injury-dependent proteolytic peptides generated from human tau protein. Among the N-terminal tau peptides, EIPEGTTAEEAGIGDTPSLEDEAAGHVTQA (a.a. 96–125) and AQPHTEIPEGTTAEEAGIGDTPSLEDEAAGHVTQARM (a.a. 91–127). Examples of tau C-terminal peptides identified include NVSSTGSIDMVDSPQLATLADEVSASLAKQGL (a.a. 410–441) and QLATLADEVSASLAKQGL (a.a. 424–441). Our peptidomic bioinformatic tools showed the association of proteases, such as CAPN1, CAPN2, and CTSL; CASP1, MMP7, and MMP9; and ELANE, GZMA, and MEP1A, in CCI-TBI tau peptidome. In clinical trials for novel TBI treatments, it might be useful to monitor a subset of tau peptidome as targets for biomarker utility and use them for a “theranostic” approach.

Traumatic brain injury (TBI) and traumatic spinal cord injury (SCI), collectively termed neurotrauma, are two parallel neurological conditions that can cause long-lasting neurological impairment and other comorbidities in patients, while at the same time, can create a high burden to society. To date, there are still no FDA-approved therapeutic interventions for either TBI or SCI. Recent advances in proteomic technologies, including tandem mass spectrometry, as well as imaging mass spectrometry, have enabled new approaches to study the differential proteome in TBI and SCI with the use of either animal disease models and/or biosamples from clinical observational studies. Thus, the applications of state-of-the-art proteomic method hold promises in shedding light on identifying clinically useful neurotrauma “biomarkers” and/or in identifying distinct and, otherwise, unobvious systems pathways or “key drivers” that can be further exploited as new therapeutic intervention targets.

Tauopathies are a class of neurodegenerative disorders characterized by abnormal deposition of post-translationally modified tau protein in the human brain. Tauopathies are associated with Alzheimer’s disease (AD), chronic traumatic encephalopathy (CTE), and other diseases. Hyperphosphorylation increases tau tendency to aggregate and forms neurofibrillary tangles (NFT), a pathological hallmark of AD. In this study, okadaic acid (OA, 100 nM), a protein phosphatase 1/2A inhibitor, was treated for 24h in mouse neuroblastoma (N2a) and differentiated rat primary neuronal cortical cell cultures (CTX) to induce tau-hyperphosphorylation and oligomerization as a cell-based tauopathy model. Following the treatments, the effectiveness of different kinase inhibitors was assessed using the tauopathy-relevant tau antibodies through tau-immunoblotting, including the sites: pSer202/pThr205 (AT8), pThr181 (AT270), pSer202 (CP13), pSer396/pSer404 (PHF-1), and pThr231 (RZ3). OA-treated samples induced tau phosphorylation and oligomerization at all tested epitopes, forming a monomeric band (46-67 kDa) and oligomeric bands (170 kDa and 240 kDa). We found that TBB (a casein kinase II inhibitor), AR and LiCl (GSK-3 inhibitors), cyclosporin A (calcineurin inhibitor), and Saracatinib (Fyn kinase inhibitor) caused robust inhibition of OA-induced monomeric and oligomeric p-tau in both N2a and CTX culture. Additionally, a cyclin-dependent kinase 5 inhibitor (Roscovitine) and a calcium chelator (EGTA) showed conflicting results between the two neuronal cultures.This study provides a comprehensive view of potential drug candidates (TBB, CsA, AR, and Saracatinib), and their efficacy against tau hyperphosphorylation and oligomerization processes. These findings warrant further experimentation, possibly including animal models of tauopathies, which may provide a putative Neurotherapy for AD, CTE, and other forms of tauopathy-induced neurodegenerative diseases.