Ataxia Telangiectasia patient-derived neuronal and brain organoid models reveal mitochondrial dysfunction and oxidative stress.

Ataxia Telangiectasia (AT) is a rare disorder caused by mutations in the ATM gene and results in progressive neurodegeneration for reasons that remain poorly understood. In addition to its central role in nuclear DNA repair, ATM operates outside the nucleus to regulate metabolism, redox homeostasis and mitochondrial function. However, a systematic investigation into how and when loss of ATM affects these parameters in relevant human neuronal models of AT was lacking. We therefore used cortical neurons and brain organoids from AT-patient iPSC and gene corrected isogenic controls to reveal levels of mitochondrial dysfunction, oxidative stress, and senescence that vary with developmental maturity. Transcriptome analyses identified disruptions in regulatory networks related to mitochondrial function and maintenance, including alterations in the PARP/SIRT signalling axis and dysregulation of key mitophagy and mitochondrial fission-fusion processes. We further show that antioxidants reduce ROS and restore neurite branching in AT neuronal cultures, and ameliorate impaired neuronal activity in AT brain organoids. We conclude that progressive mitochondrial dysfunction and aberrant ROS production are important contributors to neurodegeneration in AT and are strongly linked to ATM's role in mitochondrial homeostasis regulation.

Robot-assisted vs ultrasonography-guided transversus abdominis plane (TAP) block vs local anaesthesia in urology: results of the UROTAP randomized trial.

OBJECTIVES: To prospectively analyse robotically administered transperitoneal transversus abdominis plane (robot-assisted transversus abdominis plane [RTAP]) compared with both ultrasonography-guided transversus abdominis plane (UTAP) and local anaesthesia (LA) with regard to pain control and narcotic use in patients undergoing robot-assisted prostatectomy (RARP) or robot-assisted partial nephrectomy (RAPN). SUBJECTS/PATIENTS AND METHODS: Patients undergoing RARP or RAPN were randomized in a single-blind 2:2:1 fashion to RTAP:UTAP:LA, with the study powered to evaluate superiority of UTAP to LA and non-inferiority of RTAP to UTAP. We compared time to deliver the block, operating room time, postoperative pain scores using the visual analogue scale, and intra-operative and postoperative analgesia consumption. RESULTS: A total of 143 patients were randomized and received treatment. There was no significant difference in patient baseline characteristics. UTAP did not demonstrate superiority to LA in terms of pain control. RTAP and LA were faster to administer than UTAP (time to perform block 2.5 vs 2.5 vs 6.25 min; P < 0.001). There was no difference in postoperative narcotic, acetaminophen, ketorolac or ondansetron requirements among the three groups (P > 0.05). The study was terminated early due to the unexpected efficacy of LA. CONCLUSION: This study showed that UTAP and RTAP do not provide superior pain control to LA. The efficiency, effectiveness, and ease of administration of LA make it an excellent option for first-line therapy for postoperative analgesia.

Tips and tricks in achieving zero peri-operative opioid used in onco-urologic surgery.

PURPOSE: To review non-opioid based protocols in urologic oncologic surgery and describe our institutional methods of eliminating peri-operative opioids. METHODS: A thorough literature review was performed using PUBMED to identify articles pertaining to reducing or eliminating narcotic use in genitourinary cancer surgery. Studies were analyzed pertaining to protocols utilized in genitourinary cancer surgery, major abdominal and/or pelvic non-urologic surgery. RESULTS: Reducing or eliminating peri-operative narcotics should begin with an institutionalized protocol made in conjunction with the anesthesia department. Pre-operative regimens should consist of appropriate counseling, gabapentin, and acetaminophen with or without a non-steroidal anti-inflammatory medications. Prior to incision, a regional block or local anesthetic should be delivered. Anesthesiologists may develop opioid-free protocols for achieving and maintaining general anesthesia. Post-operatively, patients should be on a scheduled regimen of ketorolac, gabapentin, and acetaminophen. CONCLUSION: Eliminating peri-operative narcotic use is feasible for major genitourinary oncologic surgery. Patients not only have improved peri-operative outcomes but also are at significantly reduced risk of developing long-term opioid use. Through the implementation of a non-opioid protocol, urologists are able to best serve their patients while positively contributing to reducing the opioid epidemic.

Persistent Opioid Use After Combat Injury and Subsequent Long-term Risk of Abuse: A Retrospective Cohort Study.

OBJECTIVE: To determine whether persistent opioid use after injury is associated with subsequent long-term development of clinically recognized opioid abuse. SUMMARY BACKGROUND DATA: Opioid abuse is an epidemic in the United States and trauma can initiate persistent use; however, it remains unclear whether persistent opioid use contributes to the subsequent development of opioid abuse. The care of combat casualties by the Departments of Defense and Veterans Affairs uniquely allows investigation of this long-term outcome. METHODS: This retrospective cohort study randomly selected 10,000 battle-injured United States military personnel. We excluded patients who died during initial hospitalization or within 180 days of discharge, had a preinjury opioid abuse diagnosis, or had missing data in a preselected variable. We defined persistent opioid use as filling an opioid prescription 3 to 6 months after discharge and recorded clinically recognized opioid abuse using relevant diagnosis codes. RESULTS: After exclusion, 9284 subjects were analyzed, 2167 (23.3%) of whom developed persistent opioid use. During a median follow-up time of 8 years, 631 (6.8%) patients developed clinically recognized opioid abuse with a median time to diagnosis of 3 years. Injury severity and discharge opioid prescription amount were associated with persistent opioid use after trauma. After adjusting for patient and injury-specific factors, persistent opioid use was associated with the long-term development of clinically recognized opioid abuse (adjusted hazard ratio, 2.39; 95% confidence interval, 1.99-2.86). CONCLUSIONS: Nearly a quarter of patients filled an opioid prescription 3 to 6 months after discharge, and this persistent use was associated with long-term development of opioid abuse.

The Enduring Health Consequences of Combat Trauma: a Legacy of Chronic Disease.

BACKGROUND: A better understanding of the long-term health effects of combat injury is important for the management of veterans' health in the Department of Defense (DoD) and Veterans Affairs (VA) health care systems and may have implications for primary care management of civilian trauma patients. OBJECTIVE: To determine the impact of traumatic injury on the subsequent development of hypertension (HTN), diabetes mellitus (DM), and coronary artery disease (CAD) after adjustment for sociodemographic, health behavior, and mental health factors. DESIGN: Retrospective cohort study of current and former US military personnel with data obtained from both the DoD and VA health care systems. PARTICIPANTS: Combat injured (n = 8727) service members between 1 February 2002 and 14 June 2016 randomly selected from the DoD Trauma Registry matched 1:1 based on year of birth, sex, and branch of service to subjects that deployed to a combat zone but were not injured. MAIN MEASURES: Traumatic injury, stratified by severity, compared with no documented injury. Diagnoses of HTN, DM, and CAD defined by International Classification of Diseases 9th or 10th Revision Clinical Modification codes. KEY RESULTS: After adjustment, severe traumatic injury was significantly associated with HTN (HR 2.78, 95% CI 2.18-3.55), DM (HR 4.45, 95% CI 2.15-9.18), and CAD (HR 4.87, 95% CI 2.11-11.25), compared with no injury. Less severe injury was associated with HTN (HR 1.14, 95% CI 1.05-1.24) and CAD (HR 1.62, 95% CI 1.11-2.37). CONCLUSIONS: Severe traumatic injury is associated with the subsequent development of HTN, DM, and CAD. These findings have profound implications for the primary care of injured service members in both the DoD/VA health systems and may be applicable to civilian trauma patients as well. Further exploration of pathophysiologic, health behavior, and mental health changes after trauma is warranted to guide future intervention strategies.

Directional Persistence of Cell Migration in Schizophrenia Patient-Derived Olfactory Cells.

Cell migration is critical for brain development and linked to several neurodevelopmental disorders, including schizophrenia. We have shown previously that cell migration is dysregulated in olfactory neural stem cells from people with schizophrenia. Although they moved faster than control cells on plastic substrates, patient cells were insensitive to regulation by extracellular matrix proteins, which increase the speeds of control cells. As well as speed, cell migration is also described by directional persistence, the straightness of movement. The aim of this study was to determine whether directional persistence is dysregulated in schizophrenia patient cells and whether it is modified on extracellular matrix proteins. Directional persistence in patient-derived and control-derived olfactory cells was quantified from automated live-cell imaging of migrating cells. On plastic substrates, patient cells were more persistent than control cells, with straighter trajectories and smaller turn angles. On most extracellular matrix proteins, persistence increased in patient and control cells in a concentration-dependent manner, but patient cells remained more persistent. Patient cells therefore have a subtle but complex phenotype in migration speed and persistence on most extracellular matrix protein substrates compared to control cells. If present in the developing brain, this could lead to altered brain development in schizophrenia.

Managing COVID-19 from the epicenter: adaptations and suggestions based on experience.

In March 2020, the New York City metropolitan area became the epicenter of the United States' SARS-CoV-2 pandemic and the surge of new cases threatened to overwhelm the area's hospital systems. This article describes how an anesthesiology department at a large urban academic hospital rapidly adapted and deployed to meet the threat head-on. Topics included are preparatory efforts, development of a team-based staffing model, and a new strategy for resource management. While still maintaining a fully functioning operating theater, discrete teams were deployed to both COVID-19 and non-COVID-19 intensive care units, rapid response/airway management team, the difficult airway response team, and labor and delivery. Additional topics include the creation of a temporary 'pop-up' anesthesiology-run COVID-19 intensive care unit utilizing anesthesia machines for monitoring and ventilatory support as well as the development of a simulation and innovation team that was instrumental in the rapid prototyping of a controlled split-ventilation system and conversion of readily available BIPAP units into emergency ventilators. As the course of the disease is uncertain, the goal of this article is to assist others in preparation for what may come next with COVID-19 as well as potential future pandemics.

Antibody-Free Targeted Proteomics Assay for Absolute Measurement of α-Tubulin Acetylation.

Acetylation of α-tubulin at conserved lysine 40 (K40) amino acid residue regulates microtubule dynamics and controls a wide range of cellular activities. Dysregulated microtubule dynamics characterized by differential α-tubulin acetylation is a hallmark of cancer, neurodegeneration, and other complex disorders. Hence, accurate quantitation of α-tubulin acetylation is required in human disease and animal model studies. We developed a novel antibody-free proteomics assay to measure α-tubulin acetylation targeting protease AspN-generated peptides harboring K40 site. Using the synthetic unmodified and acetylated stable isotope labeled peptides DKTIGGG and DKTIGGGD, we demonstrate assay linearity across 4 log magnitude and reproducibility of <10% coefficient of variation. The assay accuracy was validated by titration of 10-80% mixture of acetylated/nonacetylated α-tubulin peptides in the background of human olfactory neurosphere-derived stem (ONS) cell matrix. Furthermore, in agreement with antibody-based high content microscopy analysis, the targeted proteomics assay reported an induction of α-tubulin K40 acetylation upon Trichostatin A stimulation of ONS cells. Independently, we found 35.99% and 16.11% α-tubulin acetylation for mouse spinal cord and brain homogenate tissue, respectively, as measured by our assay. In conclusion, this simple, antibody-free proteomics assay enables quantitation of α-tubulin acetylation, and is applicable across various fields of biology and medicine.

Urban air particulate matter induces mitochondrial dysfunction in human olfactory mucosal cells.

BACKGROUND: The adverse effects of air pollutants including particulate matter (PM) on the central nervous system is increasingly reported by epidemiological, animal and post-mortem studies in the last decade. Oxidative stress and inflammation are key consequences of exposure to PM although little is known of the exact mechanism. The association of PM exposure with deteriorating brain health is speculated to be driven by PM entry via the olfactory system. How air pollutants affect this key entry site remains elusive. In this study, we investigated effects of urban size-segregated PM on a novel cellular model: primary human olfactory mucosal (hOM) cells. RESULTS: Metabolic activity was reduced following 24-h exposure to PM without evident signs of toxicity. Results from cytometric bead array suggested a mild inflammatory response to PM exposure. We observed increased oxidative stress and caspase-3/7 activity as well as perturbed mitochondrial membrane potential in PM-exposed cells. Mitochondrial dysfunction was further verified by a decrease in mitochondria-dependent respiration. Transient suppression of the mitochondria-targeted gene, neuronal pentraxin 1 (NPTX1), was carried out, after being identified to be up-regulated in PM2.5-1 treated cells via RNA sequencing. Suppression of NPTX1 in cells exposed to PM did not restore mitochondrial defects resulting from PM exposure. In contrast, PM-induced adverse effects were magnified in the absence of NPTX1, indicating a critical role of this protein in protection against PM effects in hOM cells. CONCLUSION: Key mitochondrial functions were perturbed by urban PM exposure in a physiologically relevant cellular model via a mechanism involving NPTX1. In addition, inflammatory response and early signs of apoptosis accompanied mitochondrial dysfunction during exposure to PM. Findings from this study contribute to increased understanding of harmful PM effects on human health and may provide information to support mitigation strategies targeted at air pollution.

Cell migration in schizophrenia: Patient-derived cells do not regulate motility in response to extracellular matrix.

Schizophrenia is a highly heritable psychiatric disorder linked to a large number of risk genes. The function of these genes in disease etiology is not fully understood but pathway analyses of genomic data suggest developmental dysregulation of cellular processes such as neuronal migration and axon guidance. Previous studies of patient-derived olfactory cells show them to be more motile than control-derived cells when grown on a fibronectin substrate, motility that is dependent on focal adhesion kinase signaling. The aim of this study was to investigate whether schizophrenia patient-derived cells are responsive to other extracellular matrix (ECM) proteins that bind integrin receptors. Olfactory neurosphere-derived cells from nine patients and nine matched controls were grown on ECM protein substrates at increasing concentrations and their movement was tracked for 24h using automated high-throughput imaging. Control-derived cells increased their motility as the ECM substrate concentration increased, whereas patient-derived cell motility was little affected by ECM proteins. Patient and control cells had appropriate integrin receptors for these ECM substrates and detected them as shown by increases in focal adhesion number and size in response to ECM proteins, which also induced changes in cell morphology and cytoskeleton. These observations indicate that patient cells failed to translate the detection of ECM proteins into appropriate changes in cell motility. In a sense, patient cells act like a moving car whose accelerator is jammed, moving at the same speed without regard to the external environment. This focuses attention on cell motility regulation rather than speed as key to impairment of neuronal migration in the developing brain in schizophrenia.

Parkinson's disease-associated human ATP13A2 (PARK9) deficiency causes zinc dyshomeostasis and mitochondrial dysfunction.

Human ATP13A2 (PARK9), a lysosomal type 5 P-type ATPase, has been associated with autosomal recessive early-onset Parkinson's disease (PD). ATP13A2 encodes a protein that is highly expressed in neurons and is predicted to function as a cation pump, although the substrate specificity remains unclear. Accumulation of zinc and mitochondrial dysfunction are established aetiological factors that contribute to PD; however, their underlying molecular mechanisms are largely unknown. Using patient-derived human olfactory neurosphere cultures, which harbour loss-of-function mutations in both alleles of ATP13A2, we identified a low intracellular free zinc ion concentration ([Zn(2+)]i), altered expression of zinc transporters and impaired sequestration of Zn(2+) into autophagy-lysosomal pathway-associated vesicles, indicating that zinc dyshomeostasis occurs in the setting of ATP13A2 deficiency. Pharmacological treatments that increased [Zn(2+)]i also induced the production of reactive oxygen species and aggravation of mitochondrial abnormalities that gave rise to mitochondrial depolarization, fragmentation and cell death due to ATP depletion. The toxic effect of Zn(2+) was blocked by ATP13A2 overexpression, Zn(2+) chelation, antioxidant treatment and promotion of mitochondrial fusion. Taken together, these results indicate that human ATP13A2 deficiency results in zinc dyshomeostasis and mitochondrial dysfunction. Our data provide insights into the molecular mechanisms of zinc dyshomeostasis in PD and its contribution to mitochondrial dysfunction with ATP13A2 as a molecular link between the two distinctive aetiological factors of PD.

A Grand Challenge. 2. Phenotypic Profiling of a Natural Product Library on Parkinson's Patient-Derived Cells.

Harnessing the inherent biological relevance of natural products requires a method for the recognition of biological effects that may subsequently lead to the discovery of particular targets. An unbiased multidimensional profiling method was used to examine the activities of natural products on primary cells derived from a Parkinson's disease patient. The biological signature of 482 natural products was examined using multiparametric analysis to investigate known cellular pathways and organelles implicated in Parkinson's disease such as mitochondria, lysosomes, endosomes, apoptosis, and autophagy. By targeting several cell components simultaneously the chance of finding a phenotype was increased. The phenotypes were then clustered using an uncentered correlation. The multidimensional phenotypic screening showed that all natural products, in our screening set, were biologically relevant compounds as determined by an observed phenotypic effect. Multidimensional phenotypic screening can predict the cellular function and subcellular site of activity of new compounds, while the cluster analysis provides correlation with compounds with known mechanisms of action. This study reinforces the value of natural products as biologically relevant compounds.

Pathogens penetrating the central nervous system: infection pathways and the cellular and molecular mechanisms of invasion.

The brain is well protected against microbial invasion by cellular barriers, such as the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB). In addition, cells within the central nervous system (CNS) are capable of producing an immune response against invading pathogens. Nonetheless, a range of pathogenic microbes make their way to the CNS, and the resulting infections can cause significant morbidity and mortality. Bacteria, amoebae, fungi, and viruses are capable of CNS invasion, with the latter using axonal transport as a common route of infection. In this review, we compare the mechanisms by which bacterial pathogens reach the CNS and infect the brain. In particular, we focus on recent data regarding mechanisms of bacterial translocation from the nasal mucosa to the brain, which represents a little explored pathway of bacterial invasion but has been proposed as being particularly important in explaining how infection with Burkholderia pseudomallei can result in melioidosis encephalomyelitis.

A patient-derived olfactory stem cell disease model for ataxia-telangiectasia.

The autosomal recessive disorder ataxia-telangiectasia (A-T) is characterized by genome instability, cancer predisposition and neurodegeneration. Although the role of ataxia-telangiectasia mutated (ATM) protein, the protein defective in this syndrome, is well described in the response to DNA damage, its role in protecting the nervous system is less clear. We describe the establishment and characterization of patient-specific stem cells that have the potential to address this shortcoming. Olfactory neurosphere (ONS)-derived cells were generated from A-T patients, which expressed stem cell markers and exhibited A-T molecular and cellular characteristics that included hypersensitivity to radiation, defective radiation-induced signaling and cell cycle checkpoint defects. Introduction of full-length ATM cDNA into these cells corrected defects in the A-T cellular phenotype. Gene expression profiling and pathway analysis revealed defects in multiple cell signaling pathways associated with ATM function, with cell cycle, cell death and DNA damage response pathways being the most significantly dysregulated. A-T ONS cells were also capable of differentiating into neural progenitors, but they were defective in neurite formation, number of neurites and length of these neurites. Thus, ONS cells are a patient-derived neural stem cell model that recapitulate the phenotype of A-T, do not require genetic reprogramming, have the capacity to differentiate into neurons and have potential to delineate the neurological defect in these patients.

Variance of gene expression identifies altered network constraints in neurological disease.

Gene expression analysis has become a ubiquitous tool for studying a wide range of human diseases. In a typical analysis we compare distinct phenotypic groups and attempt to identify genes that are, on average, significantly different between them. Here we describe an innovative approach to the analysis of gene expression data, one that identifies differences in expression variance between groups as an informative metric of the group phenotype. We find that genes with different expression variance profiles are not randomly distributed across cell signaling networks. Genes with low-expression variance, or higher constraint, are significantly more connected to other network members and tend to function as core members of signal transduction pathways. Genes with higher expression variance have fewer network connections and also tend to sit on the periphery of the cell. Using neural stem cells derived from patients suffering from Schizophrenia (SZ), Parkinson's disease (PD), and a healthy control group, we find marked differences in expression variance in cell signaling pathways that shed new light on potential mechanisms associated with these diverse neurological disorders. In particular, we find that expression variance of core networks in the SZ patient group was considerably constrained, while in contrast the PD patient group demonstrated much greater variance than expected. One hypothesis is that diminished variance in SZ patients corresponds to an increased degree of constraint in these pathways and a corresponding reduction in robustness of the stem cell networks. These results underscore the role that variation plays in biological systems and suggest that analysis of expression variance is far more important in disease than previously recognized. Furthermore, modeling patterns of variability in gene expression could fundamentally alter the way in which we think about how cellular networks are affected by disease processes.

Timing of de novo mutagenesis--a twin study of sodium-channel mutations.

De novo mutations are a cause of sporadic disease, but little is known about the developmental timing of such mutations. We studied concordant and discordant monozygous twins with de novo mutations in the sodium channel α1 subunit gene (SCN1A) causing Dravet's syndrome, a severe epileptic encephalopathy. On the basis of our findings and the literature on mosaic cases, we conclude that de novo mutations in SCN1A may occur at any time, from the premorula stage of the embryo (causing disease in the subject) to adulthood (with mutations in the germ-line cells of parents causing disease in offspring).

Concise review: Patient-derived olfactory stem cells: new models for brain diseases.

Traditional models of brain diseases have had limited success in driving candidate drugs into successful clinical translation. This has resulted in large international pharmaceutical companies moving out of neuroscience research. Cells are not brains, obviously, but new patient-derived stem models have the potential to elucidate cell biological aspects of brain diseases that are not present in worm, fly, or rodent models, the work horses of disease investigations and drug discovery. Neural stem cells are present in the olfactory mucosa, the organ of smell in the nose. Patient-derived olfactory mucosa has demonstrated disease-associated differences in a variety of brain diseases and recently olfactory mucosa stem cells have been generated from patients with schizophrenia, Parkinson's disease, and familial dysautonomia. By comparison with cells from healthy controls, patient-derived olfactory mucosa stem cells show disease-specific alterations in gene expression and cell functions including: a shorter cell cycle and faster proliferation in schizophrenia, oxidative stress in Parkinson's disease, and altered cell migration in familial dysautonomia. Olfactory stem cell cultures thus reveal patient-control differences, even in complex genetic diseases such as schizophrenia and Parkinson's disease, indicating that multiple genes of small effect can converge on shared cell signaling pathways to present as a disease-specific cellular phenotype. Olfactory mucosa stem cells can be maintained in homogeneous cultures that allow robust and repeatable multiwell assays suitable for screening libraries of drug candidate molecules.

Simulation-based assessment and retraining for the anesthesiologist seeking reentry to clinical practice: a case series.

BACKGROUND: Established models for assessment and maintenance of competency in anesthesiology may not be adequate for anesthesiologists wishing to reenter practice. The authors describe a program developed in their institution incorporating simulator-based education, to help determine competency in licensed and previously licensed anesthesiologists before return to practice. METHODS: The authors have used simulation for assessment and retraining at their institution since 2002. Physicians evaluated by the authors' center undergo an adaptable 2-day simulation-based assessment conducted by two board-certified anesthesiologists. A minimum of three cases are presented on each day, with specific core competencies assessed, and participants complete a standard Clinical Anesthesia Year 3 level anesthesia knowledge test. Participants are debriefed extensively and retraining regimens are designed, where indicated, consisting of a combination of simulation and operating-room observership. RESULTS: Twenty anesthesiologists were referred to the authors' institution between 2002 and 2012. Fourteen participants (70%) were in active clinical practice 1 yr after participation in the authors' program, five (25%) were in supervised positions, and nine (45%) had resumed independent clinical practice. The reasons of participants not in practice were personal (1 participant) and medico-legal (3 participants); two participants were lost to follow-up. Two of 14 physicians, who were formally assessed in the authors' program, were deemed likely unfit for safe return to practice, irrespective of further training. These physicians were unavailable for contact 1 yr after assessment. CONCLUSION: Anesthesiologists seeking to return to active clinical status are a heterogeneous group. The simulated environment provides an effective means by which to assess baseline competency and also a way to retrain physicians.

Surface coatings of ZnO nanoparticles mitigate differentially a host of transcriptional, protein and signalling responses in primary human olfactory cells.

BACKGROUND: Inhaled nanoparticles have been reported in some instances to translocate from the nostril to the olfactory bulb in exposed rats. In close proximity to the olfactory bulb is the olfactory mucosa, within which resides a niche of multipotent cells. Cells isolated from this area may provide a relevant in vitro system to investigate potential effects of workplace exposure to inhaled zinc oxide nanoparticles. METHODS: Four types of commercially-available zinc oxide (ZnO) nanoparticles, two coated and two uncoated, were examined for their effects on primary human cells cultured from the olfactory mucosa. Human olfactory neurosphere-derived (hONS) cells from healthy adult donors were analyzed for modulation of cytokine levels, activation of intracellular signalling pathways, changes in gene-expression patterns across the whole genome, and compromised cellular function over a 24 h period following exposure to the nanoparticles suspended in cell culture medium. RESULTS: ZnO nanoparticle toxicity in hONS cells was mediated through a battery of mechanisms largely related to cell stress, inflammatory response and apoptosis, but not activation of mechanisms that repair damaged DNA. Surface coatings on the ZnO nanoparticles mitigated these cellular responses to varying degrees. CONCLUSIONS: The results indicate that care should be taken in the workplace to minimize generation of, and exposure to, aerosols of uncoated ZnO nanoparticles, given the adverse responses reported here using multipotent cells derived from the olfactory mucosa.

Reduced acetylated α-tubulin in SPAST hereditary spastic paraplegia patient PBMCs.

HSP-SPAST is the most common form of hereditary spastic paraplegia (HSP), a neurodegenerative disease causing lower limb spasticity. Previous studies using HSP-SPAST patient-derived induced pluripotent stem cell cortical neurons have shown that patient neurons have reduced levels of acetylated α-tubulin, a form of stabilized microtubules, leading to a chain of downstream effects eventuating in increased vulnerability to axonal degeneration. Noscapine treatment rescued these downstream effects by restoring the levels of acetylated α-tubulin in patient neurons. Here we show that HSP-SPAST patient non-neuronal cells, peripheral blood mononuclear cells (PBMCs), also have the disease-associated effect of reduced levels of acetylated α-tubulin. Evaluation of multiple PBMC subtypes showed that patient T cell lymphocytes had reduced levels of acetylated α-tubulin. T cells make up to 80% of all PBMCs and likely contributed to the effect of reduced acetylated α-tubulin levels seen in overall PBMCs. We further showed that mouse administered orally with increasing concentrations of noscapine exhibited a dose-dependent increase of noscapine levels and acetylated α-tubulin in the brain. A similar effect of noscapine treatment is anticipated in HSP-SPAST patients. To measure acetylated α-tubulin levels, we used a homogeneous time resolved fluorescence technology-based assay. This assay was sensitive to noscapine-induced changes in acetylated α-tubulin levels in multiple sample types. The assay is high throughput and uses nano-molar protein concentrations, making it an ideal assay for evaluation of noscapine-induced changes in acetylated α-tubulin levels. This study shows that HSP-SPAST patient PBMCs exhibit disease-associated effects. This finding can help expedite the drug discovery and testing process.