Purinergic Signaling Research Articles

Electroacupuncture may alleviate inflammatory pain by downregulating the expression of P2Y14 receptor in the primary somatosensory cortex.

Increasing evidence indicated that purinergic signalling involved in electroacupuncture (EA)-induced analgesia. Whether purinergic P2Y14 receptor contributes to EA-mediated analgesia remains unclear. Here, we report that the expression of P2Y14 receptor in the hindlimb region of the primary somatosensory cortex (S1HL) was significantly upregulated on Complete Freund's Adjuvant (CFA)-induced pain model mice, while was downregulated after EA treatment (2Hz frequency, 1mA intensity, and 30min duration) at "Zusanli" (also named ST36 acupoint). EA-mediated analgesia could be reversed by injection of P2RY14 agonist uridine diphosphate glucose (UDPG) into the bilateral S1HL, while prolonged by injection of P2RY14 antagonist pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid (PPTN). It suggested that EA may alleviate inflammatory pain by downregulating the expression of P2RY14 in the S1HL.

Purinergic signaling through the P2Y2 receptor regulates osteocytes' mechanosensitivity.

Osteocytes' response to dynamic loading plays a crucial role in regulating the bone mass but quickly becomes saturated such that downstream induction of bone formation plateaus. The underlying mechanisms that downregulate osteocytes' sensitivity and overall response to loading remain unknown. In other cell types, purinergic signaling through the P2Y2 receptor has the potential to downregulate the sensitivity to loading by modifying cell stiffness through actin polymerization and cytoskeleton organization. Herein, we examined the role of P2Y2 activation in regulating osteocytes' mechanotransduction using a P2Y2 knockout cell line alongside conditional knockout mice. Our findings demonstrate that the absence of P2Y2 expression in MLO-Y4 cells prevents actin polymerization while increasing the sensitivity to fluid flow-induced shear stress. Deleting osteocytes' P2Y2 expression in conditional-knockout mice enabled bone formation to increase when increasing the duration of exercise. Overall, P2Y2 activation under loading produces a negative feedback loop, limiting osteocytes' response to continuous loading by shifting the sensitivity to mechanical strain through actin stress fiber formation.

P2X7 expression patterns in the developing Fmr1-knockout mouse hippocampus.

Fragile-X Syndrome (FXS)is the leading monogenetic cause of intellectual disability among children but remains without a cure. Using the Fmr1 KO mouse model of FXS, much work has been done to understand FXS hippocampus dysfunction. Purinergic signaling, where ATP and its metabolites are used as signaling molecules, participates in hippocampus development, but it is unknown if purinergic signaling is affected in the developing Fmr1 KO hippocampus. In our study, we characterized the purinergic receptor P2X7. We first found that P2X7 was reduced in Fmr1 KO whole hippocampus tissue at P14 and P21, corresponding to the periods of neurite outgrowth and synaptic refinement in the hippocampus. We then evaluated the cell-specific expression of P2X7 with immunofluorescenceand found differences between WT and Fmr1 KO mice in P2X7 colocalization with hippocampal microglia and neurons. P2X7 colocalized more with microglia at P14 and P21, but there was a sex-specific reduction in P2X7 colocalization with neurons. In contrast, male mice at P14 and P21 showed reduced neuronal P2X7 colocalization compared to females, but only females showed reduced absolute neuronal P2X7 expression across the dorsal hippocampal formation. Together, our results suggest that P2X7 expression is altered during Fmr1-KO hippocampal development, potentially influencing several developmental processes in the Fmr1-KO hippocampus formation.

T Regulatory Cell Subsets Do Not Restore for One Year After Acute COVID-19.

COVID-19, caused by SARS-CoV-2, triggers a complex immune response, with T regulatory cells (Tregs) playing a crucial role in maintaining immune homeostasis and preventing excessive inflammation. The current study investigates the function of T regulatory cells during COVID-19 infection and the subsequent recovery period, emphasizing their impact on immune regulation and inflammation control. We conducted a comprehensive analysis of Treg subpopulations in peripheral blood samples from COVID-19 patients at different stages: acute infection, early convalescence, and long-term recovery. Flow cytometry was employed to quantify Tregs including "naïve", central memory (CM), effector memory (EM), and terminally differentiated CD45RA+ effector cells (TEMRA). Additionally, the functional state of the Tregs was assessed by the expression of purinergic signaling molecules (CD39, CD73). Cytokine profiles were assessed through multiplex analysis. Our findings indicate a significant decrease in the number of Tregs during the acute phase of COVID-19, which correlates with heightened inflammatory markers and increased disease severity. Specifically, we found a decrease in the relative numbers of "naïve" and an increase in EM Tregs, as well as a decrease in the absolute numbers of "naïve" and CM Tregs. During the early convalescent period, the absolute counts of all Treg populations tended to increase, accompanied by a reduction in pro-inflammatory cytokines. Despite this, one year after recovery, the decreased subpopulations of regulatory T cells had not yet reached the levels observed in healthy donors. Finally, we observed the re-establishment of CD39 expression in all Treg subsets; however, there was no change in CD73 expression among Tregs. Understanding these immunological changes across different T regulatory subsets and adenosine signaling pathways offers important insights into the disease's pathogenesis and provides a broader view of immune system dynamics during recovery.

The role of extracellular ATP in regulating the functional activity of cells

A search and analysis of scientific articles presented in the databases PubMed, ScienceDirect, Elsevier, eLibrary for 2000–2024 was carried out. The selection criterion was the presence in the articles of information on the concentration of extracellular ATP in normal and pathological tissues, the mechanisms of purinergic regulation of cell functioning, and the expression of CD73 and CD39 ectonucleotidases on cells, which regulate proinflammatory extracellular ATP catabolism to immunosuppressive adenosine. Modern data are presented on the role of extracellular ATP in the regulation of cell functioning under normal and pathological conditions, during inflammation and the formation of cellular and humoral immune responses, as well as on the study of the mechanisms of purinergic signaling from extracellular ATP in the development of targeted drugs for various diseases, including neoplasms, neurodegenerative and autoimmune pathologies.

Isosmotic Striction of Rat Aorta Smooth Muscle Cells During Activation of Purinergic Receptors: Role of Chlorine Transport

We studied the effect of the purinergic signaling system and Cl-transporters on vascular smooth muscle cells (SMC) isosmotic striction that occurs when osmotic pressure is normalized after prolonged incubation in a hypoosmotic medium. The study was performed with the method of myography on endothelium-denuded ring segments of the male Wistar rats aorta. Isosmotic striction was induced by placing the vascular segments in normosmotic Krebs solution containing 120 mM NaCl after a 40-minute incubation in a hyposmotic Krebs solution containing 40 mM NaCl. Purinergic receptors were activated by adenosine 5'-triphosphate (ATP, 500 μM) as nonselective P2X and P2Y receptor agonist, and uridine 5'-triphosphate (UTP, 500 μM) as selective P2Y receptor agonist. ATP and UTP eliminated the transient nature of the aorta SMC isosmotic striction without affecting its amplitude. Pretreatment of vascular segments with ATP and UTP during incubation in a hyposmotic solution completely suppressed the development of isosmotic striction in the presence of ATP or UTP, but did not affect isosmotic striction without activators of purinergic receptors. The inhibitor of Na+, K+, 2Cl--cotransport (NKCC) bumetanide (100 μM) abolished isosmotic striction in the presence of ATP, but not UTP, but restored its transient character. A non-selective blocker of Cl– channels and Cl–, HCO3– exchanger DIDS (100 μM) suppressed the development of isosmotic striction both in the presence of ATP and UTP. The potassium channel blocker tetraethylammonium (10 mM) potentiates the constrictor action of UTP on isosmotic striction. We suppose purinergic receptors eliminate the transient isosmotic striction by activating Cl– currents through activation of P2Y receptors. The mechanism of interaction between the purinergic signaling system and Cl– transport during changes in cell volume requires further study.

P2X7 receptor in macrophage polarization and its implications in neuroblastoma tumor behavior.

Tumor-associated macrophages (TAMs) exhibit antitumor or protumor responses related to inflammatory (or M1) and alternative (or M2) phenotypes, respectively. The P2X7 receptor plays a key role in macrophage polarization, influencing inflammation and immunosuppression. In this study, we investigated the role of the P2X7 receptor in TAMs. Using P2X7 receptor-deficient macrophages, we analyzed gene expression profiles and their implications for neuroblastoma invasion and chemoresistance. Our results showed that P2X7 receptor deficiency altered the expression of classical polarization markers, such as nitric oxide synthase 2 (Nos2) and tumor necrosis factor-α (Tnf), as well as alternative phenotype markers, including mannosereceptor C-type 1 (Mrc1) and arginase 1 (Arg1). P2X7 deficiency also influenced the expression of the ectonucleotidases Entpd1 and Nt5e and other purinergic receptors, especially P2ry2, suggesting compensatory mechanisms involved in macrophage polarization. In particular, TAMs deficient in P2X7 showed a phenotype with characteristicsintermideiate between resting macrophages (M0) and M1 polarization rather than the M2-type phenotype like and wild-type TAM macrophages. In addition, P2rx7-/- TAMs regulated the expression of P2X7 receptor isoforms in neuroblastoma cells, with downregulation of the P2X7A and B isoforms leading to a decrease in chemotherapy-induced cell death. However, TAMs expressing P2X7 downregulated only the B isoform, suggesting that TAMs play a role in modulating tumor behavior through P2X7 receptor isoform regulation. Taken together, our data underscore the regulatory function of the P2X7 receptor in orchestrating alternative macrophage polarization and in the interplay between tumor cells and TAMs. These findings help to clarify the complex interplay of purinergic signaling in cancer progression and open up avenues for future research and therapeutic interventions.

Astrocytic GLUT1 reduction paradoxically improves central and peripheral glucose homeostasis.

Astrocytes are considered an essential source of blood-borne glucose or its metabolites to neurons. Nonetheless, the necessity of the main astrocyte glucose transporter, i.e., GLUT1, for brain glucose metabolism has not been defined. Unexpectedly, we found that brain glucose metabolism was paradoxically augmented in mice with astrocytic GLUT1 reduction (GLUT1ΔGFAP mice). These mice also exhibited improved peripheral glucose metabolism especially in obesity, rendering them metabolically healthier. Mechanistically, we observed that GLUT1-deficient astrocytes exhibited increased insulin receptor-dependent ATP release, and that both astrocyte insulin signaling and brain purinergic signaling are essential for improved brain function and systemic glucose metabolism. Collectively, we demonstrate that astrocytic GLUT1 is central to the regulation of brain energetics, yet its depletion triggers a reprogramming of brain metabolism sufficient to sustain energy requirements, peripheral glucose homeostasis, and cognitive function.

Pharmacology of natural bioactive compounds used for management of Huntington diseases: An overview

Huntington's disease (HtD), an inherited genetic neurodegenerative disorder, posed threat to elderly population world-wide. HtD is caused by the repetition of cytosine-adenine-guanine (CAG) in HtD gene, which further leads to the formation of a mutant Huntington (mHtt) protein that is responsible for neuronal dysfunction and cell death. Symptoms of HtD usually begin in adulthood and progress slowly, resulting in psychiatric disturbances, motor deficits and cognitive dysfunction. The medium spiny neurons of the striatum and cortex are mainly affected in HtD. Multiple hypotheses have been proposed to elucidate the underlying mechanisms that lead to neuronal dysfunction and cell death. This typically includes molecular genetics, oxidative stress (OS), excitotoxicity, mitochondrial impairment etc. Natural bioactives are a diverse group of compounds derived from plants, animals and microorganisms. They have been found to modulate multiple signaling pathways involved in the development of HtD and have potentials in reducing OS, neuroinflammation, and neuronal death, which are key pathological processes in HtD.Mostly natural bioactive offers protection either by down-regulating the OS, excitotoxicity, mitochondrial dysfunctions, microglial inactivation, neuroinflammation and/or by upregulating ubiquitin-proteasome system, autophagy & lysosomal degradation pathway, apoptotic pathway, purinergic signaling pathway.In this chapter, we have summarized various natural bioactives that exhibit therapeutic potential against HtD. Furthermore, we have discussed the opportunities and challenges associated with the development of safe and effective natural bioactives-based therapies against HtD.

Heterologous expression and biochemical characterization of the recombinant nucleoside triphosphate diphosphohydrolase 2 (LbNTPDase2) from Leishmania (Viannia) braziliensis.

Leishmania braziliensis is a pathogenic protozoan parasite that causes American Tegumentary Leishmaniasis (ATL), an important tropical neglected disease. ENTPDases are nucleotidases that hydrolyze intracellular and/or extracellular nucleotides. ENTPDases are known as regulators of purinergic signalling induced by extracellular nucleotides. Leishmania species have two isoforms of ENTPDase, and, particularly, ENTPDase2 seems to be involved in infectivity and virulence. In this study, we conducted the heterologous expression and biochemical characterization of the recombinant ENTPDase2 of L. braziliensis (rLbNTPDase2). Our results show that this enzyme is a canonical ENTPDase with apyrase activity, capable of hydrolysing triphosphate and diphosphate nucleotides, and it is dependent on divalent cations (calcium or magnesium). Substrate specificity was characterized as UDP>GDP>ADP>GTP>ATP=UTP. The enzyme showed optimal activity at a neutral to basic pH and was partially inhibited by suramin and DIDS. Furthermore, the low apparent Km for ADP suggests that the enzyme may play a role in adenosine-mediated signalling. The biochemical characterization of this enzyme can open new avenues for using LbNTPDase2 as a drug target.

Purines and purinergic receptors in primary tumors of the central nervous system.

Purine nucleotides and nucleosides play critical roles in various pathological conditions, including tumor cell growth. Adenosine triphosphate (ATP) activates pro-tumor receptors, while adenosine (ADO) is a potent immunosuppressant and modulator of cell growth. This study aims to analyze the purinergic actions of ATP and its metabolites, associated enzymes, and P1 or P2 class receptors in primary central nervous system tumors. Additionally, we sought to correlate the levels of nucleosides and the density of P1, P2X, and P2Y receptors in cells with tumor progression. The results indicate that purinergic signaling depends on the receptor concentration and signaling molecules specific to each cell type, tissue, and tumor histology. The purinergic system may function as either a tumor-promoting agent or an antitumor factor, depending on the microenvironmental conditions and the concentrations of receptors and their respective activators. Notably, ATP emerges as the most significant extracellular signal, capable of being converted into other cellular stimulators pertinent to neoplasms, such as adenosine diphosphate, adenosine monophosphate, adenosine, and inosine. Consequently, a cascade of responses to these stimuli promotes tumor development, cell division, and metastasis. Purine nucleotides in central nervous system tumors are pivotal in cellular responses in glioblastoma multiforme, vestibular schwannoma, medulloblastoma, adenomas, gliomas, meningiomas, and pineal tumors. These findings hold the potential for developing novel therapeutic strategies and aiding in therapeutic management.

Pharmacology of P2X Receptors and Their Possible Therapeutic Potential in Obesity and Diabetes

The role of P2X ionotropic receptors in the behavior of purinergic signaling on pathophysiological processes has been widely studied. In recent years, the important participation of P2X receptors in physiological and pathological processes, such as energy metabolism, characteristic inflammatory responses of the immune system, and nociceptive activity in response to pain stimuli, has been noted. Here, we explore the molecular characteristics of the P2X receptors and the use of the different agonist and antagonist agents recently described, focusing on their potential as new therapeutic targets in the treatment of diseases with emphasis on obesity, diabetes, and some of the complications derived from these pathologies.

The Different Responsiveness of C3- and C5-deficient Murine BM Cells to Oxidative Stress Explains Why C3 Deficiency, in Contrast to C5 Deficiency, Correlates with Better Pharmacological Mobilization and Engraftment of Hematopoietic Cells.

The liver-derived circulating in peripheral blood and intrinsic cell-expressed complement known as complosome orchestrate the trafficking of hematopoietic stem/progenitor cells (HSPCs) both during pharmacological mobilization and homing/engraftment after transplantation. Our previous research demonstrated that C3 deficient mice are easy mobilizers, and their HSPCs engraft properly in normal mice. In contrast, C5 deficiency correlates with poor mobilization and defects in HSPCs' homing and engraftment. The trafficking of HSPCs during mobilization and homing/engraftment follows the sterile inflammation cues in the BM microenvironment caused by stress induced by pro-mobilizing drugs or myeloablative conditioning for transplantation. Therefore, to explain deficiencies in HSPC trafficking between C3-KO and C5-KO mice, we evaluated the responsiveness of C3 and C5 deficient cells to low oxidative stress. As reported, oxidative stress in BM is mediated by the activation of purinergic signaling, which is triggered by the elevated level of extracellular adenosine triphosphate (eATP) and by the activation of the complement cascade (ComC). In the current work, we noticed that BM lineage negative cells (lin-) isolated from C3-KO mice display several mitochondrial defects reflected by an impaired ability to adapt to oxidative stress. In contrast, C5-KO-derived BM cells show a high level of adaptation to this challenge. To support this data, C3-KO BM lin- cells were highly responsive to eATP stimulation, which correlates with enhanced levels of reactive oxygen species (ROS) generation and more efficient activation of intracellular Nlrp3 inflammasome. We conclude that the enhanced sensitivity of C3-KO mice cells to oxidative stress and better activation of the Nox2-ROS-Nlrp3 inflammasome signaling axis explains the molecular level differences in trafficking between C3- and C5-deficient HSPCs.

The potential role of purinergic signaling in cancer therapy: perspectives on anti-CD73 strategies for prostate cancer.

Purines and pyrimidines are signaling molecules in the tumor microenvironment that affect cancer immunity. The purinergic signaling pathways have been shown to play an important role in the development and progression of cancer. CD39 and CD73 are ectonucleotidases responsible for breaking down ATP or ADP into adenosine, which regulates immunosuppression in various types of cancer. These enzymes have been studied as a potential therapeutic target in immunotherapy, and recent research suggests a correlation between ectonucleotidases and clinical outcomes in cancer.Prostate cancer is the most diagnosed cancer in men, after non-melanoma skin tumors, and is the second leading cause of death in men in the world. Despite having long survival periods, patients often receive excessive or insufficient treatment. Within this complex landscape, the adenosine/CD73 pathway plays a crucial role. Therefore, this review aims to highlight new findings on the potential role of purinergic signaling in cancer treatment and emphasizes the importance of anti-CD73 as a pharmacological strategy for prostate cancer therapy.

Dysregulated Purinergic Signalling in Fragile X Syndrome Cortical Astrocytes.

The symptoms of fragile X syndrome (FXS), caused by a single gene mutation to Fmr1, have been increasingly linked to disordered astrocyte signalling within the cerebral cortex. We have recently demonstrated that the purinergic signalling pathway, which utilizes nucleoside triphosphates and their metabolites to facilitate bidirectional glial and glial-neuronal interactions, is upregulated in cortical astrocytes derived from the Fmr1 knockout (KO) mouse model of FXS. Heightened Fmr1 KO P2Y purinergic receptor levels were correlated with prolonged intracellular calcium release, elevated synaptogenic protein secretion, and hyperactivity of developing circuits. However, due to the relative lack of sensitive and reproducible quantification methods available for measuring purines and pyrimidines, determining the abundance of these factors in Fmr1 KO astrocytes was limited. We therefore developed a hydrophilic interaction liquid chromatography protocol coupled with mass spectrometry to compare the abundance of intracellular and extracellular purinergic molecules between wildtype and Fmr1 KO mouse astrocytes. Significant differences in the concentrations of UDP, ATP, AMP, and adenosine intracellular stores were found within Fmr1 KO astrocytes relative to WT. The extracellular level of adenosine was also significantly elevated in Fmr1 KO astrocyte-conditioned media in comparison to media collected from WT astrocytes. Glycosylation of the astrocyte membrane-bound CD39 ectonucleotidase, which facilitates ligand breakdown following synaptic release, was also elevated in Fmr1 KO astrocyte cultures. Together, these differences demonstrated further dysregulation of the purinergic signalling system within Fmr1 KO cortical astrocytes, potentially leading to significant alterations in FXS purinergic receptor activation and cellular pathology.

Purinergic signalling in the human placenta and functional analysis of purinoceptor P2Y6 in placental development

Purinergic signalling in the human placenta and functional analysis of purinoceptor P2Y6 in placental development

Regulation of transcription factor function by purinergic signalling in cardiovascular diseases.

Cardiovascular diseases (CVDs), including hypertension, atherosclerosis, myocardial ischemia, and myocardial infarction, constitute the primary cause of mortality worldwide. Transcription factors play critical roles in the development of CVDs and contribute to the pathophysiology of these diseases by coordinating the transcription of many genes involved in inflammation, oxidative stress, angiogenesis, and glycolytic metabolism. One important regulator of hemostasis in both healthy and pathological settings has been identified as a purinergic signalling pathway. Research has demonstrated that several signalling networks implicated in the pathophysiology of CVDs are formed by transcription factors that are regulated by purinergic substances. Here, we briefly summarize the roles and mechanisms of the transcription factors regulated by purinergic pathways in various types of CVD. This information will be essential for discovering novel approaches for CVD treatment and prevention.

Purinergic Signaling in Non-Parenchymal Liver Cells.

Purinergic signaling has emerged as an important paracrine-autocrine intercellular system that regulates physiological and pathological processes in practically all organs of the body. Although this system has been thoroughly defined since the nineties, recent research has made substantial advances regarding its role in aspects of liver physiology. However, most studies have mainly targeted the entire organ, 70% of which is made up of parenchymal cells or hepatocytes. Because of its physiological role, the liver is exposed to toxic metabolites, such as xenobiotics, drugs, and fatty acids, as well as to pathogens such as viruses and bacteria. Under injury conditions, all cell types within the liver undergo adaptive changes. In this context, the concentration of extracellular ATP has the potential to increase dramatically. Indeed, this purinergic response has not been studied in sufficient detail in non-parenchymal liver cells. In the present review, we systematize the physiopathological adaptations related to the purinergic system in chronic liver diseases of non-parenchymal liver cells, such as hepatic stellate cells, Kupffer cells, sinusoidal endothelial cells, and cholangiocytes. The role played by non-parenchymal liver cells in these circumstances will undoubtedly be strategic in understanding the regenerative activities that support the viability of this organ under stressful conditions.

Platelets isolation and ectonucleotidase assay: Revealing functional aspects of the communication between the vasculature and the immune system

Platelets are enucleated fragments of cells with a diversity of internal granules. They are responsible for functions related to hemostasis, coagulation, and inflammation. The activation of these processes depends on a cascade coordinated by cytokines, chemokines, and components of purinergic signaling, such as ATP, ADP, and adenosine. Platelets express distinct components of the purinergic system: P2X1, P2Y1, PY12, and P2Y14 receptors; and the ectonucleotidases NTPDase, NPP, and 5NTE (ecto-5′-nucleotidase). Except for P2Y14, which has not yet exhibited a known function, all other components relate to the biological processes mentioned before. Platelets are known to display specific responses to microorganisms, being capable of recognizing pathogen-associated molecular patterns (PAMPs), engulfing certain classes of viruses, and participating in NETosis. Platelet function dysregulation implicates various pathophysiological processes, including cardiovascular diseases (CVDs) and infections. In COVID-19 patients, platelets exhibit altered purinergic signaling and increased activation, contributing to inflammation. Excessive platelet activation can lead to complications from thrombosis, which can affect the circulation of vital organs. Therefore, controlling the activation is necessary to end the inflammatory process and restore homeostasis. Ectonucleotidases, capable of hydrolyzing ATP, ADP, and AMP, are of fundamental importance in activating platelets, promising pharmacological targets for clinical use as cardiovascular protective drugs. In this review, we revisit platelet biology, the purinergic receptors and ectonucleotidases on their surface, and their importance in platelet activity. Additionally, we describe methods for isolating platelets in humans and murine, as well as the main techniques for detecting the activity of ectonucleotidases in platelets. Considering the multitude of functions revealed by platelets and their potential use as potent bioreactors able to secrete and present molecules involved in the communication of the vasculature with the immune system, it is crucial to deeply understand platelet biology and purinergic signaling participation to contribute to the developing of therapeutic strategies in diseases of the cardiovascular, inflammatory, and immune systems.

A Potential Neurotoxic Mechanism: Bisphenol S-Induced Inhibition of Glucose Transporter 1 Leads to ATP Excitotoxicity in the Zebrafish Brain.

Many environmental pollutants have neurotoxic effects, but the initial molecular events involved in these effects are unclear. Here, zebrafish were exposed to the neurotoxicant bisphenol S (BPS, 1, 10, or 100 μg/L) from the embryonic stage to the larval stage to explore the ability of BPS to interfere with energy metabolism in the brain. BPS, which is similar to a glucose transporter 1 (GLUT1) inhibitor, inhibited GLUT1 function but increased mitochondrial activity in the brains of larval zebrafish. Interestingly, GLUT1 inhibitor treatment and BPS exposure did not reduce energy production in the brain; instead, they increased ATP production by inducing the preferential use of ketone bodies. Moreover, BPS promoted the protein expression of the purinergic 2X receptor but inhibited the purinergic 2Y-mediated phosphatidylinositol signaling pathway, indicating that excess ATP acts as a neurotransmitter to activate the purinergic 2X receptor under the BPS-induced restriction of GLUT1 function. BPS-induced inhibition of GLUT1 increased the number of neurons but promoted apoptosis by activating ATP-purinergic 2X receptors in the brain, causing ATP excitatory neurotoxicity. Our data reveal a potential neurotoxic mechanism induced by BPS that may represent a new adverse outcome pathway.