Proteomic profiling reveals neuronal ion channel dysregulation and cellular responses to DNA damage-induced cell cycle arrest and senescence in human neuroblastoma SH-SY5Y cells exposed to cypermethrin

A Proteomics Profiling Reveals the Neuroprotective Effects of Melatonin on Exogenous β-amyloid-42 Induced Mitochondrial Impairment, Intracellular β-amyloid Accumulation and Tau Hyperphosphorylation in Human SH-SY5Y Cells

Alzheimer's disease (AD) is prevalent in the elderly population and characterized by the intracellular accumulation of neurofibrillary tangles (NFTs), composed of tau proteins, and extracellular deposition of beta-amyloid protein (Aβ). The present study aimed to investigate the neuroprotective effects of melatonin on Aβ42-induced AD-like pathology in SH-SY5Y cell lines. To assess the effects of melatonin on Aβ42-exposed cells, we performed a proteomics analysis of altered protein expression in Aβ42-treated cells, with or without melatonin Pretreatment, using label-free nano-LC-MS/MS. Experimental validations of pathways related to the neuroprotective effects of melatonin were carried out using Milliplex amyloid beta and tau magnetic bead assays, Western blot analysis, and measurements of mitochondrial membrane potential and ROS levels. Our results show that Aβ42 exposure led to an increase in an accumulation of intracellular Aβ42/40 and phosphorylated tau (Thr181)/Tau ratios. Pretreatment with melatonin effectively reduced the levels of these pathogenic proteins. Proteomics analysis has revealed protein markers associated with the Alzheimer's disease pathway, neuronal synapses, cellular apoptosis, and mitochondrial functions. Changes in proteins regulating the mitochondrial permeability transition pore, the electron transport chain, and mitochondrial oxidative stress were observed in Aβ42-treated cells. Pretreatment with melatonin protected the cells against Aβ42-induced cellular damages by regulating the expression of several proteins underpinning these biological processes, including the suppression of mitochondrial ROS generation and mitigation of mitochondrial membrane depolarization.

Daily proteome variations highlight sustained metabolic activity in cone cells of Nrl knockout mice

Vision is a highly rhythmic function adapted to daily changes in light intensity. Rhythms disruption is known to compromise retinal health and visual function. This study investigates expression patterns of cone proteins over the 24-h daily cycle in order to understand the molecular bases of cone cyclic physiology. Cones were isolated by vibratome-sectioning from Nrl knockout mice at four time points across the 24-h LD (Light-Dark) cycle and protein extracts were quantified by label-free LC-MS/MS. The resulting protein data was then submitted to MetaCycle analysis to identify proteins with rhythmic expression patterns and associated functions. Cyclic profiles were further validated by SWATH-MS analysis. A total of 1208 proteins were identified. Rhythmic expression patterns were found for 319 proteins, categorized into four clusters based on intensity variation. SWATH-MS analysis validated the approach. Functional enrichment analysis revealed proteins critical for photoreceptor function, including those involved in phototransduction, oxidative phosphorylation, RNA processing, proteostasis, transport, synaptic function and cilia biogenesis. These findings provide a unique dataset of rhythmic cone proteins, potentially crucial for elucidating cone cell physiology and visual function. This knowledge can empower future research on preventing and treating vision impairment.

Metabolomics' Change Under β-Cypermethrin Stress and Detoxification Role of CYP5011A1 in Tetrahymena thermophila

BACKGROUND

β-cypermethrin (β-CYP) exhibits high toxicity to aquatic organisms and poses significant risks to aquatic ecosystems. Tetrahymena thermophila, a protozoa widely distributed in aquatic environments, can tolerate high concentrations of β-cypermethrin. However, the comprehensive detoxification mechanisms remain poorly understood in Tetrahymena.

METHODS

Untargeted metabolomics was used to explore the detoxification mechanisms of T. thermophila under β-CYP stress.

RESULTS

Trehalose, maltose, glycerol, and D-myo-inositol were upregulated under β-CYP exposure in Tetrahymena. Furthermore, the expression level of CYP5011A1 was upregulated under β-CYP treatment. CYP5011A1 knockout mutants resulted in a decreasing proliferation rate of T. thermophila under β-CYP stress. The valine-leucine and isoleucine biosynthesis and glycine-serine and threonine metabolism were significantly affected, with significantly changed amino acids including serine, isoleucine, and valine.

CONCLUSIONS

These findings confirmed that T. thermophila develops β-CYP tolerance by carbohydrate metabolism reprogramming and Cyp5011A1 improves cellular adaptations by influencing amino acid metabolisms. Understanding these mechanisms can inform practices aimed at reducing the adverse effects of agricultural chemicals on microbial and environmental health.

Preconception and first trimester exposure to pesticides and associations with stillbirth

Associations of pesticide exposures during preconception with stillbirth have not been well explored. We linked Arizona pesticide use records with birth certificates from 2006 to 2020 and estimated associations of living within 500 m of any pyrethroid, organophosphate (OP), or carbamate pesticide applications during a 90-day preconception window or the first trimester, with stillbirth. We considered a binary measure of exposure (any exposure), as well as log-pounds and log-acres applied within 500 m, in a negative control exposure framework with log-binomial regression. We included 1 237 750 births, 2290 stillbirths, and 27 pesticides. During preconception, any exposure to pesticides was associated with stillbirth, including cyfluthrin (risk ratio [RR] = 1.97; 95% CI, 1.17-3.32); zeta-cypermethrin (RR = 1.81; 95% CI, 1.20-2.74); OPs as a class (RR = 1.60; 95% CI, 1.16-2.19); malathion (RR = 2.02; 95% CI, 1.26-3.24); carbaryl (RR = 6.39; 95% CI, 2.07-19.74); and propamocarb hydrochloride (RR = 7.72; 95% CI, 1.10-54.20). During the first trimester, fenpropathrin (RR = 4.36; 95% CI, 1.09-17.50); permethrin (RR = 1.57; 95% CI, 1.02-2.42); OPs as a class (RR = 1.50; 95% CI, 1.11-2.01); acephate (RR = 2.31; 95% CI, 1.22-4.40); and formetanate hydrochloride (RR = 7.22; 95% CI, 1.03-50.58) were associated with stillbirth. Interpretations were consistent when using continuous measures of pounds or acres of exposure. Pesticide exposures during preconception and first trimester may be associated with stillbirth. This article is part of a Special Collection on Environmental Epidemiology.

Proteomic-miRNA Biomics Profile Reveals 2D Cultures of Human iPSC-Derived Neural Progenitor Cells More Sensitive than 3D Spheroid System Against the Experimental Exposure to Arsenic

The iPSC-derived 3D models are considered to be a connective link between 2D culture and in vivo studies. However, the sensitivity of such 3D models is yet to be established. We assessed the sensitivity of the hiPSC-derived 3D spheroids against 2D cultures of neural progenitor cells. The sub-toxic dose of Sodium Arsenite (SA) was used to investigate the alterations in miRNA-proteins in both systems. Though SA exposure induced significant alterations in the proteins in both 2D and 3D systems, these proteins were uncommon except for 20 proteins. The number and magnitude of altered proteins were higher in the 2D system compared to 3D. The association of dysregulated miRNAs with the target proteins showed their involvement primarily in mitochondrial bioenergetics, oxidative and ER stress, transcription and translation mechanism, cytostructure, etc., in both culture systems. Further, the impact of dysregulated miRNAs and associated proteins on these functions and ultrastructural changes was compared in both culture systems. The ultrastructural studies revealed a similar pattern of mitochondrial damage, while the cellular bioenergetics studies confirm a significantly higher energy failure in the 2D system than to 3D. Such a higher magnitude of changes could be correlated with a higher amount of internalization of SA in 2D cultures than in 3D spheroids. Our findings demonstrate that a 2D culture system seems better responsive than a 3D spheroid system against SA exposure.

Ion channel modulator DPI-201-106 significantly enhances antitumor activity of DNA damage response inhibitors in glioblastoma

Background

Glioblastoma, a lethal high-grade glioma, has not seen improvements in clinical outcomes in nearly 30 years. Ion channels are increasingly associated with tumorigenesis, and there are hundreds of brain-penetrant drugs that inhibit ion channels, representing an untapped therapeutic resource. The aim of this exploratory drug study was to screen an ion channel drug library against patient-derived glioblastoma cells to identify new treatments for brain cancer.

Methods

Seventy-two ion channel inhibitors were screened in patient-derived glioblastoma cells, and cell viability was determined using the ViaLight Assay. Cell cycle and apoptosis analysis were determined with flow cytometry using PI and Annexin V staining, respectively. Protein and phosphoprotein expression was determined using mass spectrometry and analyzed using gene set enrichment analysis. Kaplan-Meier survival analyses were performed using intracranial xenograft models of GBM6 and WK1 cells.

Results

The voltage-gated sodium channel modulator, DPI-201-106, was revealed to reduce glioblastoma cell viability in vitro by inducing cell cycle arrest and apoptosis. Phosphoproteomics indicated that DPI-201-106 may impact DNA damage response (DDR) pathways. Combination treatment of DPI-201-106 with the CHK1 inhibitor prexasertib or the PARP inhibitor niraparib demonstrated synergistic effects in multiple patient-derived glioblastoma cells both in vitro and in intracranial xenograft mouse models, extending survival of glioblastoma-bearing mice.

Conclusions

DPI-201-106 enhances the efficacy of DDR inhibitors to reduce glioblastoma growth. As these drugs have already been clinically tested in humans, repurposing DPI-201-106 in novel combinatorial approaches will allow for rapid translation into the clinic.

Novel insights into the role of ion channels in cellular DNA damage response

The DNA damage response (DDR) is a complex and highly regulated cellular process that detects and repairs DNA damage. The integrity of the DNA molecule is crucial for the proper functioning and survival of cells, as DNA damage can lead to mutations, genomic instability, and various diseases, including cancer. The DDR safeguards the genome by coordinating a series of signaling events and repair mechanisms to maintain genomic stability and prevent the propagation of damaged DNA to daughter cells. The study of an ion channels in the context of DDR is a promising avenue in biomedical research. Lately, it has been reported that the movement of ions through channels plays a crucial role in various physiological processes, including nerve signaling, muscle contraction, cell signaling, and maintaining cell membrane potential. Knowledge regarding the involvement of ion channels in the DDR could support refinement of our approach to several pathologies, mainly cancer, and perhaps lead to innovative therapies. In this review, we focused on the ion channel's possible role in the DDR. We present an analysis of the involvement of ion channels in DDR, their role in DNA repair mechanisms, and cellular outcomes. By addressing these areas, we aim to provide a comprehensive perspective on ion channels in the DDR and potentially guide future research in this field. It is worth noting that the interplay between ion channels and the cellular DDR is complex and multifaceted. More research is needed to fully understand the underlying mechanisms and potential therapeutic implications of these interactions.

Pyrethroids toxicity in vertebrates and invertebrates and amelioration by bioactive compounds: A review

Generations of different synthetic pesticides have been launched over time to maintain balance between production and consumption of the agricultural yield, control various disease programmes, store grains, etc. Pyrethroids, which are supposed to be non-toxic, have been excessively implemented and have contaminated soil and water bodies. Thus, pyrethroids cause severe and dreadful pernicious effects on various life forms residing in soil, air, and water. Various obnoxious effects of pyrethroids have been analyzed in the vertebrate and invertebrate systems of the animal kingdom. Pyrethroids, namely, Cypermethrin, Deltamethrin, Beta-cyfluthrin, Esfenvalerate, Fenvalerate, and Bifenthrin, have set out various types of degenerative and toxic impacts that include oxidative stress, hepatotoxicity, immunotoxicity involving thymic and splenic toxicity, neurotoxicity, nephrotoxicity, foetal toxicity, alterations in serum calcium and phosphate levels, cerebral and bone marrow degeneration, degeneration of the reproductive system, histological alteration, and DNA damage. Bioactive compounds like Diosmin, Curcumin, Rutin, Spirulina platensis, sesame oil, Naringin, Allicin, Piperine, alpha-lipoic acid, alpha-tocopherol, Cyperus rotundus L. tuber extract, herbal syrup from chicory and artichoke leaves, green tea extract, Quercetin, Trans-ferulic acid, Ascorbic acid, Propolis, ethanolic extract of grape pomace, and Melatonin have been reported to sublime the toxic effects of these pesticides. The expanding harmfulness of pesticides is a real and demanding issue that needs to be overcome, and bioactive compounds have been shown to reduce the toxicity in vivo as well as in vitro.

Neuroprotective Effects of Nano-Curcumin against Cypermethrin Associated Oxidative Stress and Up-Regulation of Apoptotic and Inflammatory Gene Expression in Rat Brains

Cypermethrin (CPM) is the most toxic synthetic pyrethroid that has established neurotoxicity through oxidative stress and neurochemical agitation in experimental rats. The toxic effects are supposed to be mediated by modifying the sodium channels, reducing Na-K ATPase, acetylcholine esterase (AchE), and monoamine oxidase (MAO). The use of curcumin nanoparticles (NC) that have potent antioxidant, anti-inflammatory and antiapoptotic properties with improved bioavailability attenuates neurotoxicity in rat brains. To test this hypothesis, animals were divided into five groups, each having six animals. Group-I control received vehicle only, while Group-II was treated with 50 mg/kg CPM. Group-III and Group-IV received both CPM and NC 2.5 mg/kg and 5 mg/kg, respectively. Group-V received 5 mg of NC alone. The CPM and NC were given by oral route. Afterwards, brain antioxidant status was measured by assessing lipid peroxidation (LPO), 4-HNE, glutathione reduced (GSH), antioxidant enzyme catalase, and superoxide dismutase (SOD) along with neurotoxicity markers Na-K ATPase, AchE, and MAO. Inflammation and apoptosis indices were estimated by ELISA, qRT-PCR, and immunohistochemistry, while morphologic changes were examined by histopathology. Observations from the study confirmed CPM-induced neurotoxicity by altering Na-K ATPase, AchE, and MAO, and by decreasing the activity of antioxidant enzymes and GSH. Oxidative stress marker LPO and the level of inflammatory interleukins IL-6, IL-1β, and TNF-α were notably high, and elevated expressions of Bax, NF-kB, and caspase-3 and -9 were reported in CPM group. However, NC treatment against CPM offers protection by improving antioxidant status and lowering LPO, inflammation, and apoptosis. The neurotoxicity marker’s enzyme successfully attenuated after NC treatment. Therefore, this study supports the administration of NC effectively ameliorated CPM-induced neurotoxicity in experimental rats.