Non-Pharmacological Treatments in Lewy Body Disease: A Systematic Review.

INTRODUCTION: Lewy body disease (LBD) is the second most common neurodegenerative disorder in patients older than 65 years. LBD is characterized by heterogeneous symptoms like fluctuation in attention, visual hallucinations, Parkinsonism, and REM sleep behaviour disorders. Considering the relevant social impact of the disease, identifying effective non-pharmacological treatments is becoming a priority. The aim of this systematic review was to provide an up-to-date literature review of the most effective non-pharmacological treatments in patients with LBD, focussing on evidence-based interventions. METHODS: Following PRISMA criteria, we carried out a systematic search through three databases (PubMed, Cochrane Libraries, and PEDro) including physical therapy (PT), cognitive rehabilitation (CR), light therapy (LT), transcranial direct current stimulation (tDCS), transcranial magnetic stimulation (TMS), electroconvulsive therapy (ECT), deep brain stimulation (DBS). All studies were qualitatively assessed using standardized tools (CARE and EPHPP). RESULTS: We obtained a total of 1,220 studies of which 23 original articles met eligibility criteria for inclusion. The total number of LBD patients included was 231; mean age was 69.98, predominantly men (68%). Some PT studies highlighted improvements in motor deficits. CR produced significant improvements in mood, cognition, and patient's quality of life and satisfaction. LT outlined a partial trend of improvements in mood and sleep quality. DBS, ECT, and TMS showed some partial improvements mainly on neuropsychiatric symptoms, whereas tDCS provided partial improvements in attention. CONCLUSION: This review highlights the efficacy of some evidence-based rehabilitation studies in LBD; however, further randomized controlled trials with larger samples are needed to provide definitive recommendations.

Molecular biomarkers correlate with brain grey and white matter changes in patients with mitochondrial m.3243A > G mutation.

INTRODUCTION: The mitochondrial DNA (mtDNA) m.3243A > G mutation in the MT-TL1 gene results in a multi-systemic disease, that is commonly associated with neurodegenerative changes in the brain. METHODS: Seventeen patients harboring the m3243A > G mutation were enrolled (age 43.1 ± 11.4 years, 10 M/7F). A panel of plasma biomarkers including lactate acid, alanine, L-arginine, fibroblast growth factor 21 (FGF-21), growth/differentiation factor 15 (GDF-15) and circulating cell free -mtDNA (ccf-mtDNA), as well as blood, urine and muscle mtDNA heteroplasmy were evaluated. Patients also underwent a brain standardized MR protocol that included volumetric T1-weighted images and diffusion-weighted MRI. Twenty sex- and age-matched healthy controls were included. Voxel-wise analysis was performed on T1-weighted and diffusion imaging, respectively with VBM (voxel-based morphometry) and TBSS (Tract-based Spatial Statistics). Ventricular lactate was also evaluated by 1H-MR spectroscopy. RESULTS: A widespread cortical gray matter (GM) loss was observed, more severe (p < 0.001) in the bilateral calcarine, insular, frontal and parietal cortex, along with infratentorial cerebellar cortex. High urine mtDNA mutation load, high levels of plasma lactate and alanine, low levels of plasma arginine, high levels of serum FGF-21 and ventricular lactate accumulation significantly (p < 0.05) correlated with the reduced brain GM density. Widespread microstructural alterations were highlighted in the white matter, significantly (p < 0.05) correlated with plasma alanine and arginine levels, with mtDNA mutation load in urine, with high level of serum GDF-15 and with high content of plasma ccf-mtDNA. CONCLUSIONS: Our results suggest that the synergy of two pathogenic mechanisms, mtDNA-related mitochondrial respiratory deficiency and defective nitric oxide metabolism, contributes to the brain neurodegeneration in m.3243A > G patients.

Brain Structure and Degeneration Staging in Friedreich Ataxia: Magnetic Resonance Imaging Volumetrics from the ENIGMA-Ataxia Working Group.

OBJECTIVE: Friedreich ataxia (FRDA) is an inherited neurological disease defined by progressive movement incoordination. We undertook a comprehensive characterization of the spatial profile and progressive evolution of structural brain abnormalities in people with FRDA. METHODS: A coordinated international analysis of regional brain volume using magnetic resonance imaging data charted the whole-brain profile, interindividual variability, and temporal staging of structural brain differences in 248 individuals with FRDA and 262 healthy controls. RESULTS: The brainstem, dentate nucleus region, and superior and inferior cerebellar peduncles showed the greatest reductions in volume relative to controls (Cohen d = 1.5-2.6). Cerebellar gray matter alterations were most pronounced in lobules I-VI (d = 0.8), whereas cerebral differences occurred most prominently in precentral gyri (d = 0.6) and corticospinal tracts (d = 1.4). Earlier onset age predicted less volume in the motor cerebellum (rmax  = 0.35) and peduncles (rmax  = 0.36). Disease duration and severity correlated with volume deficits in the dentate nucleus region, brainstem, and superior/inferior cerebellar peduncles (rmax  = -0.49); subgrouping showed these to be robust and early features of FRDA, and strong candidates for further biomarker validation. Cerebral white matter abnormalities, particularly in corticospinal pathways, emerge as intermediate disease features. Cerebellar and cerebral gray matter loss, principally targeting motor and sensory systems, preferentially manifests later in the disease course. INTERPRETATION: FRDA is defined by an evolving spatial profile of neuroanatomical changes beyond primary pathology in the cerebellum and spinal cord, in line with its progressive clinical course. The design, interpretation, and generalization of research studies and clinical trials must consider neuroanatomical staging and associated interindividual variability in brain measures. ANN NEUROL 2021;90:570-583.

Epigenomic and somatic mutations of pituitary tumors with clinical and pathological correlations in 111 patients.

OBJECTIVE: To profile clinically non-aggressive and aggressive pituitary adenomas (PAs)/pituitary neuroendocrine tumours (PitNETs) and pituitary carcinomas for somatic mutations and epigenetic alterations of genes involved in cell proliferation/differentiation, microRNAs (miRNA)/long noncoding RNA (LncRNA)-post-transcriptional regulators and therapy targets. DESIGN: Retrospective observational study. PATIENTS AND MEASUREMENTS: A total of 64 non-aggressive and 41 aggressive PAs/PitNETs and 6 pituitary carcinomas treated by endoscopic surgery with ≥1-year follow-up were included. Somatic mutations of 17 genes and DNA methylation of 22 genes were assessed. Ten normal pituitaries were used as control. RESULTS: We found at least one mutation in 17 tumours, including 6/64 non-aggressive, 10/41 aggressive PAs/PitNETs, and 1/6 pituitary carcinoma. AIP (N = 6) was the most frequently mutated gene, followed by NOTCH (4), and TP53 (3). Hypermethylation of PARP15, LINC00599, ZAP70 was more common in aggressive than non-aggressive PAs/PITNETs (p < .05). Lower levels of methylation of AIP, GNAS and PDCD1 were detected in aggressive PAs/PITNETs than non-aggressive ones (p < .05). For X-linked genes, males presented higher level of methylation of FLNA, UXT and MAGE family (MAGEA11, MAGEA1, MAGEC2) genes in aggressive vs. non-aggressive PAs/PITNETs (p < .05). In pituitary carcinomas, methylation of autosomal genes PARP15, LINC00599, MIR193 and ZAP70 was higher than in PAs/PITNETs, while X-linked genes methylation level was lower. CONCLUSIONS: Somatic mutations and methylation levels of genes involved in cell proliferation/differentiation, miRNA/LncRNA-post-transcriptional regulators and targets of antineoplastic therapies are different in non-aggressive and in aggressive PAs/PitNETs. Methylation profile also varies according to gender. Combined genetic-epigenetic analysis, in association with clinico-radiological-pathological data, may be of help in predicting PA/PitNET behaviour.

Major cerebral vessels involvement in patients with MELAS syndrome: Worth a scan? A systematic review.

Major cerebral vessels have been proposed as a target of defective mitochondrial metabolism in patients with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes syndrome (MELAS). Cerebral angiographic techniques are not routinely performed in MELAS patients. A systematic literature review was performed to identify studies describing major vessel caliber alterations in MELAS. Twenty-three studies reporting on 46 MELAS patients were included. Alterations in major caliber vessels were present in 59% (27/46) of patients. Dilation occurred in 37% (17/46) of patients, and in 88% (15/17) of them during a stroke-like episode (SLE). Stenosis was reported in 24% (11/46) of patients: 36% (4/11) related to an SLE and 64% (7/11) to dissections or degenerative changes. During an SLE, identification of intracranial vessels dilation or stenosis could be a selection tool for new treatment protocols. Outside SLE, identification of major cerebral vessels dissections and degenerative changes may help to prevent subsequent complications.

Hand classification of fMRI ICA noise components.

We present a practical "how-to" guide to help determine whether single-subject fMRI independent components (ICs) characterise structured noise or not. Manual identification of signal and noise after ICA decomposition is required for efficient data denoising: to train supervised algorithms, to check the results of unsupervised ones or to manually clean the data. In this paper we describe the main spatial and temporal features of ICs and provide general guidelines on how to evaluate these. Examples of signal and noise components are provided from a wide range of datasets (3T data, including examples from the UK Biobank and the Human Connectome Project, and 7T data), together with practical guidelines for their identification. Finally, we discuss how the data quality, data type and preprocessing can influence the characteristics of the ICs and present examples of particularly challenging datasets.

Combined Cerebellar Proton MR Spectroscopy and DWI Study of Patients with Friedreich's Ataxia.

Friedreich's ataxia (FRDA) is the commonest autosomal recessive ataxia, caused by GAA triplet expansion in the frataxin gene. Neuropathological studies in FRDA demonstrate that besides the primary neurodegeneration of the dorsal root ganglia, there is a progressive atrophy of the cerebellar dentate nucleus. Diffusion-weighted imaging (DWI) detected microstructural alterations in the cerebellum of FRDA patients. To investigate the biochemical basis of these alterations, we used both DWI and proton MR spectroscopy (1H-MRS) to study the same cerebellar volume of interest (VOI) including the dentate nucleus. DWI and 1H-MRS study of the left cerebellar hemisphere was performed in 28 genetically proven FRDA patients and 35 healthy controls. In FRDA mean diffusivity (MD) values were calculated for the same 1H-MRS VOI. Clinical severity was evaluated using the International Cooperative Ataxia Rating Scale (ICARS). FRDA patients showed a significant reduction of N-acetyl-aspartate (NAA), a neuroaxonal marker, and choline (Cho), a membrane marker, both expressed relatively to creatine (Cr), and increased MD values. In FRDA patients NAA/Cr negatively correlated with MD values (r = -0.396, p = 0.037) and with ICARS score (r = -0.669, p < 0.001). Age-normalized NAA/Cr loss correlated with the GAA expansion (r = -0.492, p = 0.008). The reduced cerebellar NAA/Cr in FRDA suggests that neuroaxonal loss is related to the microstructural changes determining higher MD values. The correlation between NAA/Cr and the severity of disability suggests that this biochemical in vivo MR parameter might be a useful biomarker to evaluate therapeutic interventions.

The effect of diffusion gradient direction number on corticospinal tractography in the human brain: an along-tract analysis.

OBJECTIVES: We evaluated diffusion imaging measures of the corticospinal tract obtained with a probabilistic tractography algorithm applied to data of two acquisition protocols based on different numbers of diffusion gradient directions (NDGDs). MATERIALS AND METHODS: The corticospinal tracts (CST) of 18 healthy subjects were delineated using 22 and 66-NDGD data. An along-tract analysis of diffusion metrics was performed to detect possible local differences due to NDGD. RESULTS: FA values at 22-NDGD showed an increase along the central portion of the CST. The mean of partial volume fraction of the orientation of the second fiber (f2) was higher at 66-NDGD bilaterally, because for 66-NDGD data the algorithm more readily detects dominant fiber directions beyond the first, thus the increase in FA at 22-NDGD is due to a substantially reduced detection of crossing fiber volume. However, the good spatial correlation between the tracts drawn at 22 and 66 NDGD shows that the extent of the tract can be successfully defined even at lower NDGD. CONCLUSIONS: Given the spatial tract localization obtained even at 22-NDGD, local analysis of CST can be performed using a NDGD compatible with clinical protocols. The probabilistic approach was particularly powerful in evaluating crossing fibers when present.

Precuneal Thickness and Depression in Parkinson Disease.

BACKGROUND: Depression-related gray matter changes in Parkinson disease (PD) patients have been reported, although studies investigating cortical thickness in early-stage disease are lacking. OBJECTIVE: We aimed to evaluate cortical changes related to depression in early-stage PD patients with an extensive neuropsychological evaluation. METHODS: 17 PD patients and 22 healthy controls underwent a 1.5-T brain MR protocol, and voxel-wise differences in cortical thickness among patients with (n = 6) and without (n = 11) depression and controls were evaluated using FreeSurfer software. RESULTS: Cortical thickness was increased in the precuneus bilaterally in PD patients with depression compared to the other groups (number of vertices >100; p < 0.001, uncorrected) with a direct correlation with the Beck Depression Inventory score (p < 0.001, uncorrected). CONCLUSION: Precuneal cortical thickening is evident in PD patients with mild-moderate depression even in the early stages of the disease. This finding may reflect the early involvement of this region in the development of PD-related depression.

A time-domain nuclear magnetic resonance study of Mediterranean scleractinian corals reveals skeletal-porosity sensitivity to environmental changes.

Mediterranean corals are a natural model for studying global warming, as the Mediterranean basin is expected to be one of the most affected regions and the increase in temperature is one of the greatest threats for coral survival. We have analyzed for the first time with time-domain nuclear magnetic resonance (TD-NMR) the porosity and pore-space structure, important aspects of coral skeletons, of two scleractinian corals, Balanophyllia europaea (zooxanthellate) and Leptopsammia pruvoti (nonzooxanthellate), taken from three different sites on the western Italian coast along a temperature gradient. Comparisons have been made with mercury intrusion porosimetry and scanning electron microscopy images. TD-NMR parameters are sensitive to changes in the pore structure of the two coral species. A parameter, related to the porosity, is larger for L. pruvoti than for B. europaea, confirming previous non-NMR results. Another parameter representing the fraction of the pore volume with pore sizes of less than 10-20 µm is inversely related, with a high degree of statistical significance, to the mass of the specimen and, for B. europaea, to the temperature of the growing site. This effect in the zooxanthellate species, which could reduce its resistance to mechanical stresses, may depend on an inhibition of the photosynthetic process at elevated temperatures and could have particular consequences in determining the effects of global warming on these species.

Subthalamic nucleus shows opposite functional connectivity pattern in Huntington's and Parkinson's disease.

Huntington's and Parkinson's disease are two movement disorders representing mainly opposite states of the basal ganglia inhibitory function. Despite being an integral part of the cortico-subcortico-cortical circuitry, the subthalamic nucleus function has been studied at the level of detail required to isolate its signal only through invasive studies in Huntington's and Parkinson's disease. Here, we tested whether the subthalamic nucleus exhibited opposite functional signatures in early Huntington's and Parkinson's disease. We included both movement disorders in the same whole-brain imaging study, and leveraged ultra-high-field 7T MRI to achieve the very fine resolution needed to investigate the smallest of the basal ganglia nuclei. Eleven of the 12 Huntington's disease carriers were recruited at a premanifest stage, while 16 of the 18 Parkinson's disease patients only exhibited unilateral motor symptoms (15 were at Stage I of Hoehn and Yahr off medication). Our group comparison interaction analyses, including 24 healthy controls, revealed a differential effect of Huntington's and Parkinson's disease on the functional connectivity at rest of the subthalamic nucleus within the sensorimotor network, i.e. an opposite effect compared with their respective age-matched healthy control groups. This differential impact in the subthalamic nucleus included an area precisely corresponding to the deep brain stimulation 'sweet spot'-the area with maximum overall efficacy-in Parkinson's disease. Importantly, the severity of deviation away from controls' resting-state values in the subthalamic nucleus was associated with the severity of motor and cognitive symptoms in both diseases, despite functional connectivity going in opposite directions in each disorder. We also observed an altered, opposite impact of Huntington's and Parkinson's disease on functional connectivity within the sensorimotor cortex, once again with relevant associations with clinical symptoms. The high resolution offered by the 7T scanner has thus made it possible to explore the complex interplay between the disease effects and their contribution on the subthalamic nucleus, and sensorimotor cortex. Taken altogether, these findings reveal for the first time non-invasively in humans a differential, clinically meaningful impact of the pathophysiological process of these two movement disorders on the overall sensorimotor functional connection of the subthalamic nucleus and sensorimotor cortex.

Multimodal investigation of melanopsin retinal ganglion cells in Alzheimer's disease.

OBJECTIVE: In Alzheimer's disease (AD), the presence of circadian dysfunction is well-known and may occur early in the disease course. The melanopsin retinal ganglion cell (mRGC) system may play a relevant role in contributing to circadian dysfunction. In this study, we aimed at evaluating, through a multimodal approach, the mRGC system in AD at an early stage of disease. METHODS: We included 29 mild-moderate AD (70.9 ± 11 years) and 26 (70.5 ± 8 years) control subjects. We performed an extensive neurophtalmological evaluation including optical coherence tomography with ganglion cell layer segmentation, actigraphic evaluation of the rest-activity rhythm, chromatic pupillometry analyzed with a new data-fitting approach, and brain functional MRI combined with light stimuli assessing the mRGC system. RESULTS: We demonstrated a significant thinning of the infero-temporal sector of the ganglion cell layer in AD compared to controls. Moreover, we documented by actigraphy the presence of a circadian-impaired AD subgroup. Overall, circadian measurements worsened by age. Chromatic pupillometry evaluation highlighted the presence of a pupil-light response reduction in the rod condition pointing to mRGC dendropathy. Finally, brain fMRI showed a reduced occipital cortex activation with blue light particularly for the sustained responses. INTERPRETATION: Overall, the results of this multimodal innovative approach clearly document a dysfunctional mRGC system at early stages of disease as a relevant contributing factor for circadian impairment in AD providing also support to the use of light therapy in AD.

What Can Resting-State fMRI Data Analysis Explain about the Functional Brain Connectivity in Glioma Patients?

Resting-state functional MRI has been increasingly implemented in imaging protocols for the study of functional connectivity in glioma patients as a sequence able to capture the activity of brain networks and to investigate their properties without requiring the patients' cooperation. The present review aims at describing the most recent results obtained through the analysis of resting-state fMRI data in different contexts of interest for brain gliomas: the identification and localization of functional networks, the characterization of altered functional connectivity, and the evaluation of functional plasticity in relation to the resection of the glioma. An analysis of the literature showed that significant and promising results could be achieved through this technique in all the aspects under investigation. Nevertheless, there is room for improvement, especially in terms of stability and generalizability of the outcomes. Further research should be conducted on homogeneous samples of glioma patients and at fixed time points to reduce the considerable variability in the results obtained across and within studies. Future works should also aim at establishing robust metrics for the assessment of the disruption of functional connectivity and its recovery at the single-subject level.

In Vivo Parieto-Occipital White Matter Metabolism Is Correlated with Visuospatial Deficits in Adult DM1 Patients.

Myotonic dystrophy type 1 (DM1) is a genetic disorder caused by a (CTG) expansion in the DM protein kinase (DMPK) gene, representing the most common adult muscular dystrophy, characterized by a multisystem involvement with predominantly skeletal muscle and brain affection. Neuroimaging studies showed widespread white matter changes and brain atrophy in DM1, but only a few studies investigated the role of white matter metabolism in the pathophysiology of central nervous system impairment. We aim to reveal the relationship between the metabolic profile of parieto-occipital white matter (POWM) as evaluated with proton MR spectroscopy technique, with the visuoperceptual and visuoconstructional dysfunctions in DM1 patients. MR spectroscopy (3 Tesla) and neuropsychological evaluations were performed in 34 DM1 patients (19 F, age: 46.4 ± 12.1 years, disease duration: 18.7 ± 11.6 years). The content of neuro-axonal marker N-acetyl-aspartate, both relative to Creatine (NAA/Cr) and to myo-Inositol (NAA/mI) resulted significantly lower in DM1 patients compared to HC (p-values < 0.0001). NAA/Cr and NAA/mI correlated with the copy of the Rey-Osterrieth complex figure (r = 0.366, p = 0.033; r = 0.401, p = 0.019, respectively) and with Street's completion tests scores (r = 0.409, p = 0.016; r = 0.341, p = 0.048 respectively). The proportion of white matter hyperintensities within the MR spectroscopy voxel did not correlate with the metabolite content. In this study, POWM metabolic alterations in DM1 patients were not associated with the white matter morphological changes and correlated with specific neuropsychological deficits.

The Combination of Metabolic Posterior Cingulate Cortical Abnormalities and Structural Asymmetries Improves the Differential Diagnosis Between Primary Progressive Aphasia and Alzheimer's Disease.

Differential diagnosis between primary progressive aphasia (PPA) and Alzheimer's disease (AD) could be difficult if based on clinical grounds alone. We evaluated the combination of proton MR spectroscopy of posterior cingulate cortex (PCC) and quantitative structural imaging asymmetries to differentiate PPA from AD patients. A greater left-lateralized temporo-parietal atrophy (higher accuracy for the PCC, 81.4%) and metabolic neurodegenerative changes in PCC (accuracy 76.8%) was demonstrated in PPA versus AD. The combined multiparametric approach increased the accuracy to 94%in the differential diagnosis between these two neurodegenerative diseases.

Brain functional MRI responses to blue light stimulation in Leber's hereditary optic neuropathy.

Melanopsin retinal ganglion cells (mRGCs) are intrinsically photosensitive photoreceptors contributing both to image and non-image-forming (NIF) functions of the eye. They convey light signal to the brain to modulate circadian entrainment, sleep, alertness, cognition, brightness perception and coarse vision. Given that rods and cones also contribute to all these impacts of light, isolating mRGC visual and NIF roles in humans is challenging so that mRGC functions remains to be fully characterized. Here, we evaluated light-driven visual and cognitive brain responses in Leber's Hereditary Optic Neuropathy (LHON), an inherited optic neuropathy that is characterized by a selective relative sparing of the melanopsin-expressing retinal ganglion cells (mRGCs). Twelve patients and twelve matched healthy controls (HC) were enrolled in a functional brain magnetic resonance imaging (fMRI) protocol including visual and visual-cognitive paradigms under blue (480 nm) and red (620 nm) light exposures. Primary visual cortex activation was detected in LHON patients; in particular higher occipital activation was found in response to sustained blue vs. red stimulation in LHON vs. HC. Similarly, brain responses to the executive task were larger under blue vs. red light in LHON over lateral prefrontal cortex. These findings are in line with the relative mRGC sparing demonstrated in LHON and support the mRGC contribution to both non-visual and visual brain functions, with potential implication for visual rehabilitation in hereditary optic neuropathy patients.

Brain MRS correlates with mitochondrial dysfunction biomarkers in MELAS-associated mtDNA mutations.

OBJECTIVE: The purpose of this study was to investigate correlations between brain proton magnetic resonance spectroscopy (1 H-MRS) findings with serum biomarkers and heteroplasmy of mitochondrial DNA (mtDNA) mutations. This study enrolled patients carrying mtDNA mutations associated with Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like episodes (MELAS), and MELAS-Spectrum Syndrome (MSS). METHODS: Consecutive patients carrying mtDNA mutations associated with MELAS and MSS were recruited and their serum concentrations of lactate, alanine, and heteroplasmic mtDNA mutant load were evaluated. The brain protocol included single-voxel 1 H-MRS (1.5T) in the medial parieto-occipital cortex (MPOC), left cerebellar hemisphere, parieto-occipital white matter (POWM), and lateral ventricles. Relative metabolite concentrations of N-acetyl-aspartate (NAA), choline (Cho), and myo-inositol (mI) were estimated relative to creatine (Cr), using LCModel 6.3. RESULTS: Six patients with MELAS (age 28 ± 13 years, 3 [50%] female) and 17 with MSS (age 45 ± 11 years, 7 [41%] female) and 39 sex- and age-matched healthy controls (HC) were enrolled. These patients demonstrated a lower NAA/Cr ratio in MPOC compared to HC (p = 0.006), which inversely correlated with serum lactate (p = 0.021, rho = -0.68) and muscle mtDNA heteroplasmy (p < 0.001, rho = -0.80). Similarly, in the cerebellum patients had lower NAA/Cr (p < 0.001), Cho/Cr (p = 0.002), and NAA/mI (p = 0.001) ratios, which negatively correlated with mtDNA blood heteroplasmy (p = 0.001, rho = -0.81) and with alanine (p = 0.050, rho = -0.67). Ventricular lactate was present in 78.3% (18/23) of patients, correlating with serum lactate (p = 0.024, rho = 0.58). CONCLUSION: Correlations were found between the peripheral and biochemical markers of mitochondrial dysfunction and brain in vivo markers of neurodegeneration, supporting the use of both biomarkers as signatures of MELAS and MSS disease, to evaluate the efficacy of potential treatments.

An Evolutionary Cancer Epigenetic Approach Revealed DNA Hypermethylation of Ultra-Conserved Non-Coding Elements in Squamous Cell Carcinoma of Different Mammalian Species.

BACKGROUND: Ultra-conserved non-coding elements (UCNEs) are genomic sequences that exhibit > 95% sequence identity between humans, mammals, birds, reptiles, and fish. Recent findings reported their functional role in cancer. The aim of this study was to evaluate the DNA methylation modifications of UNCEs in squamous cell carcinoma (SCC) from different mammal species. METHODS: Fifty SCCs from 26 humans, 17 cats, 3 dogs, 1 horse, 1 bovine, 1 badger, and 1 porcupine were investigated. Fourteen feline stomatitis and normal samples from 36 healthy human donors, 7 cats, 5 dogs, 5 horses, 2 bovines and 1 badger were collected as normal controls. Bisulfite next generation sequencing evaluated the DNA methylation level from seven UCNEs (uc.160, uc.283, uc.416, uc.339, uc.270, uc.299, and uc.328). RESULTS: 57/59 CpGs were significantly different according to the Kruskal-Wallis test (p < 0.05) comparing normal samples with SCC. A common DNA hypermethylation pattern was observed in SCCs from all the species evaluated in this study, with an increasing trend of hypermethylation starting from normal mucosa, through stomatitis to SCC. CONCLUSIONS: Our findings indicate that UCNEs are hypermethylated in human SCC, and this behavior is also conserved among different species of mammals.

Author Correction: Calcium mishandling in absence of primary mitochondrial dysfunction drives cellular pathology in Wolfram Syndrome.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Calcium mishandling in absence of primary mitochondrial dysfunction drives cellular pathology in Wolfram Syndrome.

Wolfram syndrome (WS) is a recessive multisystem disorder defined by the association of diabetes mellitus and optic atrophy, reminiscent of mitochondrial diseases. The role played by mitochondria remains elusive, with contradictory results on the occurrence of mitochondrial dysfunction. We evaluated 13 recessive WS patients by deep clinical phenotyping, including optical coherence tomography (OCT), serum lactic acid at rest and after standardized exercise, brain Magnetic Resonance Imaging, and brain and muscle Magnetic Resonance Spectroscopy (MRS). Finally, we investigated mitochondrial bioenergetics, network morphology, and calcium handling in patient-derived fibroblasts. Our results do not support a primary mitochondrial dysfunction in WS patients, as suggested by MRS studies, OCT pattern of retinal nerve fiber layer loss, and, in fibroblasts, by mitochondrial bioenergetics and network morphology results. However, we clearly found calcium mishandling between endoplasmic reticulum (ER) and mitochondria, which, under specific metabolic conditions of increased energy requirements and in selected tissue or cell types, may turn into a secondary mitochondrial dysfunction. Critically, we showed that Wolframin (WFS1) protein is enriched at mitochondrial-associated ER membranes and that in patient-derived fibroblasts WFS1 protein is completely absent. These findings support a loss-of-function pathogenic mechanism for missense mutations in WFS1, ultimately leading to defective calcium influx within mitochondria.