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Background Gene dosage imbalance caused by copy number variations (CNVs) is a prominent contributor to brain disorders. In particular, 15q11.2 CNV duplications and deletions have been associated with autism spectrum disorder and schizophrenia, respectively. The mechanism underlying these diametric contributions remains unclear. Methods We established both loss-of-function and gain-of-function mouse models of Cyfip1, one of four genes within 15q11.2 CNVs. To assess the functional consequences of altered CYFIP1 levels, we performed systematic investigations on behavioral, electrophysiological, and biochemical phenotypes in both mouse models. In addition, we utilized RNA immunoprecipitation sequencing (RIP-seq) analysis to reveal molecular targets of CYFIP1 in vivo. Results Cyfip1 loss-of-function and gain-of function mouse models exhibited distinct and shared behavioral abnormalities related to autism spectrum disorder and schizophrenia. RIP-seq analysis identified messenger RNA targets of CYFIP1 in vivo, including postsynaptic NMDA receptor (NMDAR) complex components. In addition, these mouse models showed diametric changes in levels of postsynaptic NMDAR complex components at synapses because of dysregulated protein translation, resulting in bidirectional alteration of NMDAR-mediated signaling. Importantly, pharmacological balancing of NMDAR signaling in these mouse models with diametric Cyfip1 dosages rescues behavioral abnormalities. Conclusions CYFIP1 regulates protein translation of NMDAR and associated complex components at synapses to maintain normal synaptic functions and behaviors. Our integrated analyses provide insight into how gene dosage imbalance caused by CNVs may contribute to divergent neuropsychiatric disorders.

Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). In this study, we generated a transgenic model by crossing germline Parkin–/–mice with PolgAD257Amice, an established model of premature aging and mitochondrial stress. We hypothesized that loss of Parkin–/–in PolgAD257A/D257Amice would exacerbate mitochondrial dysfunction, leading to loss of dopamine neurons and nigral-striatal specific neurobehavioral motor dysfunction. We found that aged Parkin–/–/PolgAD257A/D257Amale and female mice exhibited severe behavioral deficits, nonspecific to the nigral-striatal pathway, with neither dopaminergic neurodegeneration nor reductions in striatal dopamine. We saw no difference in expression levels of nuclear-encoded subunits of mitochondrial markers and mitochondrial Complex I and IV activities, although we did observe substantial reductions in mitochondrial-encoded COX41I, indicating mitochondrial dysfunction as a result of PolgAD257A/D257AmtDNA mutations. Expression levels of mitophagy markers LC3I/LC3II remained unchanged between cohorts, suggesting no overt mitophagy defects. Expression levels of the parkin substrates, VDAC, NLRP3, and AIMP2 remained unchanged, suggesting no parkin dysfunction. In summary, we were unable to observe dopaminergic neurodegeneration with corresponding nigral-striatal neurobehavioral deficits, nor Parkin or mitochondrial dysfunction in Parkin–/–/PolgAD257A/D257Amice. These findings support a lack of synergism of Parkin loss on mitochondrial dysfunction in mouse models of mitochondrial deficits.SIGNIFICANCE STATEMENTProducing a mouse model of Parkinson's disease (PD) that is etiologically relevant, recapitulates clinical hallmarks, and exhibits reproducible results is crucial to understanding the underlying pathology and in developing disease-modifying therapies. Here, we show that Parkin–/–/PolgAD257A/D257Amice, a previously reported PD mouse model, fails to reproduce a Parkinsonian phenotype. We show that these mice do not display dopaminergic neurodegeneration nor nigral-striatal-dependent motor deficits. Furthermore, we report that Parkin loss does not synergize with mitochondrial dysfunction. Our results demonstrate that Parkin–/–/PolgAD257A/D257Amice are not a reliable model for PD and adds to a growing body of work demonstrating that Parkin loss does not synergize with mitochondrial dysfunction in mouse models of mitochondrial deficits.

Introduction: It has been hypothesized that certain persistent physical symptoms (PPS) may be linked to unresolved traumatic or distressing somatic-symptom related memories. EMDR intervention targets and reintegrates distressing memories, thus reducing the re-experiencing of physical sensations. The primary aim of this review was to examine effectiveness of EMDR for PPS. Secondary aims were to investigate effectiveness of EMDR on secondary outcomes (post-traumatic stress, anxiety, and depression), and to evaluate the acceptability of EMDR for this client group.Method: Six electronic databases (PsycInfo, PsycArticles, CINAHL, MEDLINE, Web of Science and SCOPUS) were searched for peer-reviewed literature, with no restrictions on publication dates. Twenty-eight studies met inclusion criteria. Studies were included if the primary aim of EMDR intervention was to reduce intensity, frequency or reported distress associated with PPS. Studies were quality appraised using the MMAT tool prior to narrative synthesis of key findings.Results: Studies varied in design and included RCT, UCT, case study and case series. EMDR treatment length varied between studies; 1–20 sessions. All studies reported significant improvement in PPS at post-test. Effect sizes were available to report in five studies and ranged from moderate to large. Improvement in secondary outcomes were reported in all repeated measure studies. Where available, large effect sizes were reported for reduction in anxiety and depression. Overall drop-out rates in studies with representative samples was low (10.6%). Quality of research varied; low (42.8%), medium (21.4%), and high (35.7%).Conclusions: There is promising emerging evidence for effectiveness and acceptability of EMDR for a range of PPS. However, firm conclusions on efficacy cannot be made. While comparisons between PPS presentations cannot be drawn due to methodological differences, the findings for pain and tinnitus are the most compelling due to methodological quality. High-quality sufficiently powered RCTs are recommended to determine efficacy.

To assess the association between vitamin B12 (B12) deficiency and the prevalence of fatigue and prespecified neurologic symptoms in patients with fibromyalgia.A retrospective chart analysis of patients diagnosed with fibromyalgia in the years 2015-2020 was performed. The values of B12 were collected. The chart reviews assessed reported fatigue and neurologic symptoms, including brain fog, memory loss, cognitive impairment, paresthesias, numbness, and tingling, to assess their correlation with B12 levels. Concurrent vitamin D and thyroid-stimulating hormone levels were reviewed to assess their association with fibromyalgia.A total of 2142 patients with fibromyalgia with documented levels of B12 and vitamin D were included. Of them, 42.4% had B12 deficiency (400 ng/L). Fatigue and memory loss were more common in the B12 deficiency group. After adjusting for vitamin D levels, B12 deficiency remained statistically significantly associated with the presence of fatigue (odds ratio, 1.39; 95% confidence interval, 1.11-1.75;This is the first study to report the association of B12 in patients with fibromyalgia complaining of fatigue. This symptom was prevalent in our group of patients with fibromyalgia with B12 deficiency, regardless of whether the cutoff point was 400 or 350 ng/L.

An impacted tooth is one that has not erupted or is unlikely to erupt into its functional position within the dental arch1, and which has remained embedded in the jawbone or mucosa for more than 2 years following its physiological eruption time2 . It may be visible, not visible but palpable, or neither visible nor palpable but evident on a radiograph.1,3 Third molars are the most commonly impacted teeth followed by maxillary canines, with reported variations in prevalence amongst different population groups2,4. In 2000 The National Institute for Health and Clinical Excellence (NICE) issued guidelines stating that third molars should only be removed if there is evidence of pathology, and advocated that the practice of prophylactic removal be discontinued.1

PARP-1 over-activation results in cell death via excessive PAR generation in different cell types, including neurons following brain ischemia. Glycolysis, mitochondrial function, and redox balance are key cellular processes altered in brain ischemia. Studies show that PAR generated after PARP-1 over-activation can bind hexokinase-1 (HK-1) and result in glycolytic defects and subsequent mitochondrial dysfunction. HK-1 is the neuronal hexokinase and catalyzes the first reaction of glycolysis, converting glucose to glucose-6-phosphate (G6P), a common substrate for glycolysis, and the pentose phosphate pathway (PPP) (Wilson, 2003). PPP is critical in maintaining NADPH and GSH levels via G6P dehydrogenase activity. Therefore, defects in HK-1 will not only decrease cellular bioenergetics but will also cause redox imbalance due to the depletion of GSH. In brain ischemia, whether PAR-mediated inhibition of HK-1 results in bioenergetics defects and redox imbalance is not known. We used oxygen-glucose deprivation (OGD) in mouse cortical neurons to mimic brain ischemia in neuronal cultures and observed that PARP-1 activation via PAR formation alters glycolysis, mitochondrial function, and redox homeostasis in neurons. We used pharmacological inhibition of PARP and adenoviral-mediated overexpression of wild-type HK-1 (wtHK-1) and PAR-binding mutant HK-1 (pbmHK-1). Our data show that PAR inhibition or overexpression of HK-1 significantly improves glycolysis, mitochondrial function, redox homeostasis, and cell survival in mouse cortical neurons exposed to OGD. These results suggest that PAR binding and inhibition of HK-1 during OGD drives bioenergetic defects in neurons due to inhibition of glycolysis and impairment of mitochondrial function. Significance: Brain ischemia is a leading cause of death and disability. Bioenergetic collapse, mitochondrial defects, and oxidative stress are early pathological pathways elicited after PARP-1 activation in brain ischemia. This study revealed a critical finding that PAR generated by oxygen-glucose deprivation inhibits HK-1 and results in glycolytic defects, mitochondrial dysfunction, and oxidative stress in neurons. This study suggests that PAR binding to HK-1 is a pathological process and that strategies targeted to block PAR interaction with HK-1 may be beneficial in limiting neuronal injury after ischemia.

The spread of prion-like protein aggregates is believed to be a common driver of pathogenesis in many neurodegenerative diseases. Accumulated tangles of filamentous Tau protein are considered pathogenic lesions of Alzheimer’s disease (AD) and related Tauopathies, including progressive supranuclear palsy, and corticobasal degeneration. Tau pathologies in these illnesses exhibits a clear progressive and hierarchical spreading pattern that correlates with disease severity1, 2. Clinical observation combined with complementary experimental studies3, 4have shown that Tau preformed fibrils (PFF) are prion-like seeds that propagate pathology by entering cells and templating misfolding and aggregation of endogenous Tau. While several receptors of Tau are known, they are not specific to the fibrillar form of Tau. Moreover, the underlying cellular mechanisms of Tau PFF spreading remains poorly understood. Here, we show that the lymphocyte-activation gene 3 (Lag3) is a cell surface receptor that binds to PFF, but not monomer, of Tau. Deletion ofLag3or inhibition of Lag3 in primary cortical neurons significantly reduces the internalization of Tau PFF and subsequent Tau propagation and neuron-to-neuron transmission. Propagation of Tau pathology and behavioral deficits induced by injection of Tau PFF in the hippocampus and overlying cortex are attenuated in mice lackingLag3selectively in neurons. Our results identify neuronal Lag3 as a receptor of pathologic Tau in the brain, and for AD and related Tauopathies a therapeutic target.One Sentence SummaryLag3 is a neuronal receptor specific for Tau PFF, and is required for uptake, propagation and transmission of Tau pathology.

Background: Recent observational study evidence suggests that clozapine, unlike other antipsychotics, may be associated with a small increased risk of hematological malignancy. This study described characteristics of hematological and other cancers in those taking clozapine reported to the Australian Therapeutic Goods Administration. Methods: We analyzed public case reports for “clozapine,” “Clozaril,” or “Clopine” from January 1995 to December 2020 classified as “neoplasm benign, malignant and unspecified” by the Australian Therapeutic Goods Administration. Data on age, sex, dose, clozapine start and cessation dates, Medical Dictionary for Regulatory Activities reaction terms, and date of cancer were extracted. Results: Overall, 384 spontaneous reports of cancers in people taking clozapine were analyzed. The mean age of patients was 53.9 years (SD, 11.4 years), and 224 (58.3%) were male. The most frequent cancers were hematological (n = 104 [27.1%]), lung (n = 50 [13.0%]), breast (n = 37 [9.6%]), and colorectal (n = 28 [7.3%]). The outcome was fatal for 33.9% of cancer reports. Lymphoma comprised 72.1% of all hematological cancers (mean patient age, 52.1 years; SD, 11.6 years). The median daily dose of clozapine at the time of hematological cancer report was 400 mg (interquartile range, 300–543.8 mg), and the median duration of clozapine use before hematological cancer diagnosis was 7.0 years (interquartile range, 2.8–13.2 years). Conclusions: Lymphoma and other hematological cancers are overrepresented in spontaneous adverse event reports compared with other cancer types. Clinicians should be aware of the possible association with hematological cancers and monitor for and report any hematological cancers identified. Future studies should examine histology of lymphomas in people using clozapine and corresponding blood level of clozapine. Refereed/Peer-reviewed

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High-dose chemotherapy with melphalan followed by autologous transplantation is a first-line treatment for multiple myeloma. Here, we present preclinical evidence that this treatment may be significantly improved by the addition of exportin 1 inhibitors (XPO1i). The XPO1i selinexor, eltanexor, and KOS-2464 sensitized human multiple myeloma cells to melphalan. Human 8226 and U266 multiple myeloma cell lines and melphalan-resistant cell lines (8226-LR5 and U266-LR6) were highly sensitized to melphalan by XPO1i. Multiple myeloma cells from newly diagnosed and relapsed/refractory multiple myeloma patients were also sensitized by XPO1i to melphalan. In NOD/SCIDγ mice challenged with either parental 8226 or U266 multiple myeloma and melphalan-resistant multiple myeloma tumors, XPO1i/melphalan combination treatments demonstrated stronger synergistic antitumor effects than single-agent melphalan with minimal toxicity. Synergistic cell death resulted from increased XPO1i/melphalan-induced DNA damage in a dose-dependent manner and decreased DNA repair. In addition, repair of melphalan-induced DNA damage was inhibited by selinexor, which decreased melphalan-induced monoubiquitination of FANCD2 in multiple myeloma cells. Knockdown of FANCD2 was found to replicate the effect of selinexor when used with melphalan, increasing DNA damage (γH2AX) by inhibiting DNA repair. Thus, combination therapies that include selinexor or eltanexor with melphalan may have the potential to improve treatment outcomes of multiple myeloma in melphalan-resistant and newly diagnosed patients. The combination of selinexor and melphalan is currently being investigated in the context of high-dose chemotherapy and autologous transplant (NCT02780609).Significance:Inhibition of exportin 1 with selinexor synergistically sensitizes human multiple myeloma to melphalan by inhibiting Fanconi anemia pathway-mediated DNA repair.

Purpose: To determine the maximum tolerated dose (MTD) of topotecan in combination with ifosfamide, mesna, and etoposide (TIME), followed by autologous hematopoietic cell transplant (HCT), in patients with chemotherapy-refractory malignancies.Experimental Design: Patients were treated with (in mg/m2/d) ifosfamide 3,333, mesna 3,333, and topotecan 3.3 to 28.3 during days −8 through −6 and etoposide 500 (days −5 through −3) followed by HCT on day 0. Once MTD was defined, we expanded this dosing cohort to include patients with high-risk lymphoma due to activity seen during dose escalation. Topotecan pharmacokinetic analyses were carried out, and topoisomerase I levels and activity were measured.Results: The topotecan MTD in this regimen was 64 mg/m2 (21.3 mg/m2/d). Mucositis was dose limiting and correlated with topotecan dose level and area under the curve (AUC). Dose level was also correlated with length of hospitalization, number of days of parenteral nutrition, and neutrophil and platelet engraftment. Topotecan AUC was significantly correlated with time to platelet recovery. The baseline peripheral blood mononuclear cell topoisomerase I level was found to be a significant positive predictor for overall and progression-free survival. Topotecan AUC was positively correlated with dose level, with a trend toward decreasing clearance with increasing dose.Conclusion: Topotecan can be a useful drug in the high-dose setting given its activity in some malignancies when given in standard dose. Pharmacokinetic monitoring may be a valuable tool for optimizing the use of topotecan and to avoid toxicity seen with high-systemic exposures. Baseline topoisomerase I levels may have an important role in predicting topotecan efficacy. Clin Cancer Res; 17(24); 7743–53. ©2011 AACR.

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Purpose:Induction chemotherapy results in complete remission (CR) rates of 20% to 50% among patients with poor-risk AML. Selinexor is an oral selective inhibitor of nuclear export with promising single-agent activity. By inhibiting the primary export protein, XPO1, selinexor localizes and activates tumor suppressor proteins in the nucleus and inhibits DNA damage repair, rationalizing combination with DNA-damaging agents.Patients and Methods:This was a single-arm phase I clinical trial of selinexor combined with cytarabine and daunorubicin (7+3). Dose escalation was selinexor alone (3+3) with an expansion at the MTD. Cohorts 1 and 2 received 60 and 80 mg orally, respectively, twice weekly during induction. Consolidation cycles (≤ 2) with selinexor at induction dose plus 5+2 were allowed for patients who achieved CR. MTD and recommended phase II dose of selinexor were the primary endpoints.Results:Twenty-one patients with poor-risk AML were enrolled. All 21 patients were included in the safety evaluations and survival analyses (4 in each of 2 cohorts; 13 in the expansion); 8 (53%) of the 19 patients evaluable for response achieved CR/CRi. MTD was not reached. Selinexor 80 mg (orally, twice weekly) was used in the expansion phase. The most common grade 3/4 nonhematologic treatment-emergent adverse events were febrile neutropenia (67%), diarrhea (29%), hyponatremia (29%), and sepsis (14%). At median follow-up (28.9 months), 38% of patients were alive. Median overall survival was 10.3 months.Conclusions:Selinexor plus 7+3 is a safe regimen for patients with newly diagnosed poor-risk AML and warrants further investigation in a larger clinical trial.

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Cerebral ischemia and reperfusion initiate cellular events in brain that lead to neurological disability. Investigating these cellular events provides ample targets for developing new treatments. Despite considerable work, no such therapy has translated into successful stroke treatment. Among other issues—such as incomplete mechanistic knowledge and faulty clinical trial design—a key contributor to prior translational failures may be insufficient scientific rigor during preclinical assessment: nonblinded outcome assessment; missing randomization; inappropriate sample sizes; and preclinical assessments in young male animals that ignore relevant biological variables, such as age, sex, and relevant comorbid diseases. Promising results are rarely replicated in multiple laboratories. We sought to address some of these issues with rigorous assessment of candidate treatments across 6 independent research laboratories. The Stroke Preclinical Assessment Network (SPAN) implements state-of-the-art experimental design to test the hypothesis that rigorous preclinical assessment can successfully reduce or eliminate common sources of bias in choosing treatments for evaluation in clinical studies. SPAN is a randomized, placebo-controlled, blinded, multilaboratory trial using a multi-arm multi-stage protocol to select one or more putative stroke treatments with an implied high likelihood of success in human clinical stroke trials. The first stage of SPAN implemented procedural standardization and experimental rigor. All participating research laboratories performed middle cerebral artery occlusion surgery adhering to a common protocol and rapidly enrolled 913 mice in the first of 4 planned stages with excellent protocol adherence, remarkable data completion and low rates of subject loss. SPAN stage 1 successfully implemented treatment masking, randomization, prerandomization inclusion/exclusion criteria, and blinded assessment to exclude bias. Our data suggest that a large, multilaboratory, preclinical assessment effort to reduce known sources of bias is feasible and practical. Subsequent SPAN stages will evaluate candidate treatments for potential success in future stroke clinical trials using aged animals and animals with comorbid conditions.