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Background: With bipolar disorder (BD) having a lifetime prevalence of 4.4% and a significant portion of patients being chronically burdened by symptoms, there has been an increased focus on uncovering new targets for intervention in BD. One area that has shown early promise is the mitochondrial hypothesis. However, at the time of publication no studies have utilized positron emission tomography (PET) imaging to assess mitochondrial function in the setting of BD., Case Presentation: Our participant is a 58 year-old male with a past medical history notable for alcohol use disorder and BD (unspecified type) who underwent PET imaging with the mitochondrial complex I PET ligand 18 F-BCPP-EF. The resulting images demonstrated significant overlap between areas of dysfunction identified with the 18 F-BCPP-EF PET ligand and prior functional magnetic resonance imaging (MRI) techniques in the setting of BD. That overlap was seen in both affective and cognitive circuits, with mitochondrial dysfunction in the fronto-limbic, ventral affective, and dorsal cognitive circuits showing particularly significant differences., Conclusions: Despite mounting evidence implicating mitochondria in BD, this study represents the first PET imaging study to investigate this mechanistic connection. There were key limitations in the form of comorbid alcohol use disorder, limited statistical power inherent to a case study, no sex matched controls, and the absence of a comprehensive psychiatric history. However, even with these limitations in mind, the significant overlap between dysfunction previously demonstrated on functional MRI and this imaging provides compelling preliminary evidence that strengthens the mechanistic link between mitochondrial dysfunction and BD., Competing Interests: None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of West China School of Medicine/West China Hospital (WCSM/WCH) of Sichuan University.)

Background: Anxiety in Parkinson disease (PD) negatively impacts quality of life. While research predominantly focuses on central nervous system changes, some evidence suggests a connection between peripheral autonomic dysfunctions and PD-related anxiety. The role of the peripheral autonomic nervous system in this context may be overlooked., Objectives: This study explores the link between anxiety symptoms and cardiac sympathetic denervation in PD using 11 C-meta-hydroxyephedrine ([ 11 C]HED) PET cardiac imaging., Methods: We studied 34 non-demented PD subjects, assessing anxiety levels through the Spielberg Anxiety State-Trait test trait section (STAI-T). Patients underwent comprehensive assessments along with [ 11 C]HED cardiac and [ 11 C]DTBZ brain PET. To identify subdimensions of STAI-T, we employed principal components analysis (PCA). We examined associations between the anxiety subdimensions and two measures of cardiac sympathetic denervation from [ 11 C]HED PET. We utilized correlation and linear regression models for these analyses., Results: PCA revealed two STAI-T results components: anxiety-depressive and pure anxiety subcomponents. Only pure anxiety significantly correlated with measures of cardiac sympathetic denervation (rhos -0.40, p = 0.018; 0.35, p = 0.043). Regression models confirmed a significant association, with cardiac sympathetic denervation explaining ∼20 % of pure anxiety variance, independent of sex, dopaminergic impairment, and anxiolytic treatments., Discussion: This study provides preliminary evidence of peripheral autonomic nervous system abnormalities contributing to PD-related anxiety, suggesting dysregulation in peripheral autonomic functions influencing anxiety perception., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

There is growing interest in the investigation of ketogenic diets as a potential therapy for bipolar disorder. The overlapping pharmacotherapies utilized for both bipolar disorder and seizures suggest that a mechanistic overlap may exist between these conditions, with fasting and the ketogenic diet representing the most time-proven therapies for seizure control. Recently, preliminary evidence has begun to emerge supporting a potential role for ketogenic diets in treating bipolar disorder. Notably, some patients may struggle to initiate a strict diet in the midst of a mood episode or significant life stressors. The key question addressed by this pilot clinical trial protocol is if benefits can be achieved with a less restrictive diet, as this would allow such an intervention to be accessible for more patients. Recent development of so-called ketone esters, that once ingested is converted to natural ketone bodies, combined with low glycemic index dietary changes has the potential to mimic two foundational components of therapeutic ketosis: high levels of ketones and minimal spiking of glucose/insulin. This pilot clinical trial protocol thus aims to investigate the effect of a 'ketogenic-mimicking diet' (combining supplementation of ketone esters with a low glycemic index dietary intervention) on neural network stability, mood, and biomarker outcomes in the setting of bipolar disorder. Positive findings obtained via this pilot clinical trial protocol may support future target engagement studies of ketogenic-mimicking diets or related ketogenic interventions. A lack of positive findings, in contrast, may justify a focus on more strict dietary interventions for future research.

Two near-infrared fluorescent probes ( A and B ) containing hemicyanine structures appended to dipicolylamine (DPA), and a dipicolylamine derivative where one pyridine was substituted with pyrazine, respectively, were synthesized and tested for the identification of Zn(II) ions in live cells. In both probes, an acetyl group is attached to the phenolic oxygen atom of the hemicyanine platform to decrease the probe fluorescence background. Probe A displays sensitive fluorescence responses and binds preferentially to Zn(II) ions over other metal ions such as Cd 2+ ions with a low detection limit of 0.45 nM. In contrast, the emission spectra of probe B is not significantly affected if Zn(II) ions are added. Probe A possesses excellent membrane permeability and low cytotoxicity, allowing for sensitive imaging of both exogenously supplemented Zn(II) ions in live cells, and endogenously releases Zn(II) ions in cells after treatment of 2,2-dithiodipyridine., Competing Interests: The authors declare no conflict of interest.

An aggregation-induced emission (AIE) cyanine-based fluorescent cassette with a large pseudo-Stokes shift was designed and prepared to sensitively image pH changes in live cells via through-bond energy transfer (TBET) from a tetraphenylethene (TPE) donor to a cyanine acceptor.