Pub Date : 2024-12-16eCollection Date: 2025-01-01DOI: 10.1093/braincomms/fcae455
Samantha Weber, Natascha Stoffel, Juan Ansede-Bermejo, Raquel Cruz, Álvaro Del Real Bolt, Rupert Bruckmaier, Ángel Carracedo, Selma Aybek
Individuals diagnosed with functional neurological disorder experience abnormal movement, gait, sensory processing or functional seizures, for which research into the pathophysiology identified psychosocial contributing factors as well as promising biomarkers. Recent pilot studies suggested that (epi-)genetic variants may act as vulnerability factors, for example, on the oxytocin pathway. This study set out to explore endogenous oxytocin hormone levels in saliva in a cohort of 59 functional neurological disorder patients and 65 healthy controls comparable in sex and age. First, we examined the association between salivary oxytocin levels with the genetic allelic variant (rs53576) of the oxytocin receptor gene (OXTR), its epigenetic changes indicated by methylation rates, and clinical variables-including childhood trauma. Second, due to previously reported effects of oxytocin changing the volume and functional connectivity of the amygdala, as well as the known involvement of the amygdala in the pathophysiology of functional neurological disorders, we further looked at both structural and functional imaging of the amygdala. While patients did not significantly differ from healthy control in their peripheral oxytocin levels, there was a specific interaction of OXTR methylation and peripheral oxytocin dependent on group: higher methylation rates correlated with higher salivary oxytocin in patients only, while this was not the case in healthy control [F(1109) = 8.92, P = 0.003, d = 0.541]. Moreover, patients with the AA-genotype (minor allele) of the rs53576 genetic variant of the OXTR gene presented with higher OXTR methylation levels [F(2106) = 10.25, P < 0.0001, d = 0.58]. Lastly, amygdalar connectivity to the hippocampus, the posterior cingulate cortex, the inferior parietal cortex and the inferior temporal cortex as well as smaller amygdalar volume were correlated to peripheral oxytocin levels in patients only [F(2,38) = 5.36, P = 0.025, d = 0.431], but not in healthy control. No significant interactions with childhood trauma were identified. Our study revealed a significant interplay between peripheral oxytocin and OXTR methylation in patients only, potentially influenced by genotype. One could hypothesize that higher peripheral oxytocin denotes a compensatory mechanisms for the increased methylation of the OXTR, which might affect amygdalar functional connectivity. These findings help to further understand underlying pathophysiological mechanisms, considering oxytocin's involvement in functional patients and could offer a potential site of treatment for future studies.
被诊断为功能性神经障碍的个体会经历异常的运动、步态、感觉处理或功能性癫痫发作,病理生理学研究确定了社会心理因素以及有希望的生物标志物。最近的初步研究表明,(epi-)基因变异可能作为易感因素,例如,在催产素途径上。本研究旨在探讨59名功能性神经障碍患者和65名性别和年龄相当的健康对照者唾液中的内源性催产素水平。首先,我们研究了唾液催产素水平与催产素受体基因(OXTR)的等位基因变异(rs53576)、甲基化率显示的表观遗传变化以及包括童年创伤在内的临床变量之间的关系。其次,由于先前报道的催产素改变杏仁核的体积和功能连接的影响,以及已知的杏仁核参与功能性神经疾病的病理生理学,我们进一步研究了杏仁核的结构和功能成像。虽然患者的外周催产素水平与健康对照组没有显著差异,但OXTR甲基化与外周催产素之间存在特定的相互作用:只有患者的甲基化率较高,唾液催产素水平较高,而健康对照组并非如此[F(1109) = 8.92, P = 0.003, d = 0.541]。此外,携带OXTR基因rs53576遗传变异aa基因型(次要等位基因)的患者OXTR甲基化水平较高[F(2106) = 10.25, P 0.0001, d = 0.58]。最后,杏仁核与海马、后扣带皮层、下顶叶皮层和下颞叶皮层的连通性以及较小的杏仁核体积仅在患者中与外周催产素水平相关[F(2,38) = 5.36, P = 0.025, d = 0.431],而在健康对照组中则无关。未发现与儿童创伤有显著的相互作用。我们的研究揭示了外周催产素和OXTR甲基化之间的显著相互作用,仅在患者中,可能受到基因型的影响。人们可以假设,外周催产素水平的升高表明了OXTR甲基化增加的补偿机制,这可能会影响杏仁核的功能连接。这些发现有助于进一步了解潜在的病理生理机制,考虑到催产素在功能性患者中的作用,并可能为未来的研究提供潜在的治疗场所。
{"title":"Salivary oxytocin and amygdalar alterations in functional neurological disorders.","authors":"Samantha Weber, Natascha Stoffel, Juan Ansede-Bermejo, Raquel Cruz, Álvaro Del Real Bolt, Rupert Bruckmaier, Ángel Carracedo, Selma Aybek","doi":"10.1093/braincomms/fcae455","DOIUrl":"10.1093/braincomms/fcae455","url":null,"abstract":"<p><p>Individuals diagnosed with functional neurological disorder experience abnormal movement, gait, sensory processing or functional seizures, for which research into the pathophysiology identified psychosocial contributing factors as well as promising biomarkers. Recent pilot studies suggested that (epi-)genetic variants may act as vulnerability factors, for example, on the oxytocin pathway. This study set out to explore endogenous oxytocin hormone levels in saliva in a cohort of 59 functional neurological disorder patients and 65 healthy controls comparable in sex and age. First, we examined the association between salivary oxytocin levels with the genetic allelic variant (rs53576) of the oxytocin receptor gene (<i>OXTR</i>), its epigenetic changes indicated by methylation rates, and clinical variables-including childhood trauma. Second, due to previously reported effects of oxytocin changing the volume and functional connectivity of the amygdala, as well as the known involvement of the amygdala in the pathophysiology of functional neurological disorders, we further looked at both structural and functional imaging of the amygdala. While patients did not significantly differ from healthy control in their peripheral oxytocin levels, there was a specific interaction of <i>OXTR</i> methylation and peripheral oxytocin dependent on group: higher methylation rates correlated with higher salivary oxytocin in patients only, while this was not the case in healthy control [<i>F</i>(1109) = 8.92, <i>P</i> = 0.003, <i>d</i> = 0.541]. Moreover, patients with the AA-genotype (minor allele) of the rs53576 genetic variant of the <i>OXTR</i> gene presented with higher <i>OXTR</i> methylation levels [<i>F</i>(2106) = 10.25, <i>P <</i> 0.0001, <i>d</i> = 0.58]. Lastly, amygdalar connectivity to the hippocampus, the posterior cingulate cortex, the inferior parietal cortex and the inferior temporal cortex as well as smaller amygdalar volume were correlated to peripheral oxytocin levels in patients only [<i>F</i>(2,38) = 5.36, <i>P</i> = 0.025, <i>d</i> = 0.431], but not in healthy control. No significant interactions with childhood trauma were identified. Our study revealed a significant interplay between peripheral oxytocin and <i>OXTR</i> methylation in patients only, potentially influenced by genotype. One could hypothesize that higher peripheral oxytocin denotes a compensatory mechanisms for the increased methylation of the <i>OXTR</i>, which might affect amygdalar functional connectivity. These findings help to further understand underlying pathophysiological mechanisms, considering oxytocin's involvement in functional patients and could offer a potential site of treatment for future studies.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"7 1","pages":"fcae455"},"PeriodicalIF":4.1,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11670354/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142901224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-14eCollection Date: 2025-01-01DOI: 10.1093/braincomms/fcae454
Emre Fertan, Christy Hung, John S H Danial, Jeff Y L Lam, Pranav Preman, Giulia Albertini, Elizabeth A English, Dorothea Böken, Frederick J Livesey, Bart De Strooper, Rickie Patani, David Klenerman
Extracellular beta-amyloid aggregation and inflammation are in a complex and not fully understood interplay during hyperphosphorylated tau aggregation and pathogenesis of Alzheimer's disease. Our group has previously shown that an immune challenge with tumour necrosis factor alpha can alter extracellular beta-sheet containing aggregates in human-induced pluripotent stem cell-derived cortical neurons carrying familial Alzheimer's disease-related presenilin 1 mutations. Here, using single-molecule detection and super-resolution imaging techniques, we quantified and characterized the intra- and extracellular beta-amyloid and AT8-positive tau aggregates. Our results indicate a pre-existing Alzheimer's disease-like pathology caused by the presenilin 1 mutation, with increased beta-amyloid aggregates in both the cell lysate and conditioned media compared to isogenic controls and also increased intracellular tau aggregates. The main effect of tumour necrosis factor alpha treatment on presenilin 1 neurons was the formation of larger intracellular beta-amyloid aggregates. In contrast, isogenic controls showed more significant changes with tumour necrosis factor alpha treatment with an increase in beta-amyloid aggregates in the media but not intracellularly and an increase in tau aggregates in both the media and cell lysate, suggesting a chronic inflammation-driven mechanism for the development of sporadic Alzheimer's disease. Remarkably, we also found significant morphological differences between intra- and extracellular beta-amyloid and tau aggregates in human-induced pluripotent stem cell-derived cortical neurons, suggesting these neurons can only clear aggregates when small, and that larger aggregates stay inside the neurons. While majority of the beta-amyloid aggregates were cleared into the media, a greater portion of the tau aggregates remained intracellular. This size-dependent aggregate clearance was also shown to be conserved in vivo, using soaked and homogenized mouse and human post-mortem Alzheimer's disease brain samples. As such, our results are proposing a previously unknown, size-dependent aggregate clearance mechanism, which can possibly explain the intracellular aggregation of tau and extracellular aggregation of beta-amyloid.
{"title":"Clearance of beta-amyloid and tau aggregates is size dependent and altered by an inflammatory challenge.","authors":"Emre Fertan, Christy Hung, John S H Danial, Jeff Y L Lam, Pranav Preman, Giulia Albertini, Elizabeth A English, Dorothea Böken, Frederick J Livesey, Bart De Strooper, Rickie Patani, David Klenerman","doi":"10.1093/braincomms/fcae454","DOIUrl":"10.1093/braincomms/fcae454","url":null,"abstract":"<p><p>Extracellular beta-amyloid aggregation and inflammation are in a complex and not fully understood interplay during hyperphosphorylated tau aggregation and pathogenesis of Alzheimer's disease. Our group has previously shown that an immune challenge with tumour necrosis factor alpha can alter extracellular beta-sheet containing aggregates in human-induced pluripotent stem cell-derived cortical neurons carrying familial Alzheimer's disease-related presenilin 1 mutations. Here, using single-molecule detection and super-resolution imaging techniques, we quantified and characterized the intra- and extracellular beta-amyloid and AT8-positive tau aggregates. Our results indicate a pre-existing Alzheimer's disease-like pathology caused by the presenilin 1 mutation, with increased beta-amyloid aggregates in both the cell lysate and conditioned media compared to isogenic controls and also increased intracellular tau aggregates. The main effect of tumour necrosis factor alpha treatment on presenilin 1 neurons was the formation of larger intracellular beta-amyloid aggregates. In contrast, isogenic controls showed more significant changes with tumour necrosis factor alpha treatment with an increase in beta-amyloid aggregates in the media but not intracellularly and an increase in tau aggregates in both the media and cell lysate, suggesting a chronic inflammation-driven mechanism for the development of sporadic Alzheimer's disease. Remarkably, we also found significant morphological differences between intra- and extracellular beta-amyloid and tau aggregates in human-induced pluripotent stem cell-derived cortical neurons, suggesting these neurons can only clear aggregates when small, and that larger aggregates stay inside the neurons. While majority of the beta-amyloid aggregates were cleared into the media, a greater portion of the tau aggregates remained intracellular. This size-dependent aggregate clearance was also shown to be conserved <i>in vivo</i>, using soaked and homogenized mouse and human post-mortem Alzheimer's disease brain samples. As such, our results are proposing a previously unknown, size-dependent aggregate clearance mechanism, which can possibly explain the intracellular aggregation of tau and extracellular aggregation of beta-amyloid.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"7 1","pages":"fcae454"},"PeriodicalIF":4.1,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11694676/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142924191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-13eCollection Date: 2025-01-01DOI: 10.1093/braincomms/fcae451
Raffaele Cacciaglia, Mahnaz Shekari, Gemma Salvadó, Marta Milà-Alomà, Carles Falcon, Gonzalo Sánchez-Benavides, Carolina Minguillón, Karine Fauria, Oriol Grau-Rivera, José Luis Molinuevo, Kaj Blennow, Henrik Zetterberg, Frances-Catherine Quevenco, Marc Suárez-Calvet, Juan Domingo Gispert
CSF concentrations of β-amyloid 42 (Aβ42) and phosphorylated tau (p-tau) are well-established biomarkers of Alzheimer's disease and have been studied in relation to several neuropathological features both in patients and in cognitively unimpaired individuals. The CSF p-tau/Aβ42 ratio, a biomarker combining information from both pathophysiological processes, has emerged as a promising tool for monitoring disease progression, even at pre-clinical stages. Here, we studied the association between the CSF p-tau/Aβ42 ratio with downstream markers of pre-clinical Alzheimer's disease progression including brain structure, glucose metabolism, fibrillary Aβ deposition and cognitive performance in 234 cognitively unimpaired individuals, who underwent cognitive testing, a lumbar puncture, MRI, 18F-fluorodeoxyglucose and 18F-flutemetamol PET scanning. We evaluated both main effects and interactions with Alzheimer's disease risk factors, such as older age, female sex and the apoliporoptein E (APOE)-ɛ4 allele, in a priori defined regions of interest and further examined the associations on the whole-brain using voxel-wise regressions. In addition, as the association between CSF Alzheimer's disease biomarkers and brain structure and function may be non-linear, we tested the interaction between the CSF p-tau/Aβ42 ratio and stages of pre-clinical Alzheimer's disease defined using the amyloid (A) and tau (T) classification. We found significantly positive associations between CSF p-tau/Aβ42 and both cortical Aβ deposition and regional grey matter volume while no effect was observed for brain metabolism. A significant interaction with age indicated that, for the same level of CSF p-tau/Aβ42, older individuals displayed both increased Aβ deposition and lower grey matter volume, in widespread cortical areas. In addition, we found that women compared with men had a greater Aβ fibrillary accumulation in midline cortical areas and inferior temporal regions, for the same level of the CSF biomarker. The impact of CSF p-tau/Aβ42 on grey matter volume was modulated by AT stages, with A+T+ individuals displaying significantly less positive associations in areas of early atrophy in the Alzheimer's continuum. Finally, we found that sex and APOE-ɛ4 modulated the association between the CSF biomarker and episodic memory as well as abstract reasoning, respectively. Our data indicate that the CSF p-tau/Aβ42 ratio is strongly associated with multiple downstream neuropathological events in cognitively unimpaired individuals and may thus serve as a potent biomarker to investigate the earliest changes in pre-clinical Alzheimer's disease. Given that its impact on both Aβ deposition and grey matter volume is modulated by specific risk factors, our results highlight the need to take into account such predisposing variables in both clinical practice and prevention trials.
脑脊液中β-淀粉样蛋白42 (a - β42)和磷酸化tau (p-tau)的浓度是公认的阿尔茨海默病的生物标志物,并已被研究与患者和认知功能未受损个体的几种神经病理特征有关。CSF p-tau/ a - β42比值是一种结合两种病理生理过程信息的生物标志物,即使在临床前阶段,也已成为监测疾病进展的有前途的工具。在这里,我们研究了脑脊液p-tau/ a - β42比值与临床前阿尔茨海默病进展的下游标志物之间的关系,包括脑结构、葡萄糖代谢、原纤维a - β沉积和认知表现,234名认知功能未受损的个体接受了认知测试、腰椎穿刺、MRI、18f -氟脱氧葡萄糖和18f -氟替他莫PET扫描。我们评估了阿尔茨海默病风险因素的主要影响和相互作用,如年龄较大,女性和载脂蛋白E (APOE)- 4等位基因,在先验定义的感兴趣区域,并进一步使用体素回归检查了全脑的关联。此外,由于脑脊液阿尔茨海默病生物标志物与大脑结构和功能之间的关联可能是非线性的,我们测试了脑脊液p-tau/A - β42比值与使用淀粉样蛋白(A)和tau (T)分类定义的临床前阿尔茨海默病分期之间的相互作用。我们发现脑脊液p-tau/ a - β42与皮层a - β沉积和区域灰质体积呈显著正相关,而对脑代谢没有影响。与年龄的显著相互作用表明,对于相同水平的脑脊液p-tau/A - β42,老年人在广泛的皮层区域表现出A - β沉积增加和灰质体积减少。此外,我们发现,对于相同水平的脑脊液生物标志物,与男性相比,女性在皮层中线区域和颞下区有更大的a β原纤维积聚。脑脊液p-tau/A - β42对灰质体积的影响由AT分期调节,A+T+个体在阿尔茨海默病连续体的早期萎缩区域显示出明显较少的正相关。最后,我们发现性别和APOE- 4分别调节脑脊液生物标志物与情景记忆和抽象推理之间的关联。我们的数据表明,脑脊液p-tau/ a - β42比值与认知未受损个体的多种下游神经病理事件密切相关,因此可能作为研究临床前阿尔茨海默病早期变化的有效生物标志物。鉴于其对Aβ沉积和灰质体积的影响是由特定的危险因素调节的,我们的研究结果强调了在临床实践和预防试验中考虑这些易感变量的必要性。
{"title":"The CSF p-tau/β-amyloid 42 ratio correlates with brain structure and fibrillary β-amyloid deposition in cognitively unimpaired individuals at the earliest stages of pre-clinical Alzheimer's disease.","authors":"Raffaele Cacciaglia, Mahnaz Shekari, Gemma Salvadó, Marta Milà-Alomà, Carles Falcon, Gonzalo Sánchez-Benavides, Carolina Minguillón, Karine Fauria, Oriol Grau-Rivera, José Luis Molinuevo, Kaj Blennow, Henrik Zetterberg, Frances-Catherine Quevenco, Marc Suárez-Calvet, Juan Domingo Gispert","doi":"10.1093/braincomms/fcae451","DOIUrl":"10.1093/braincomms/fcae451","url":null,"abstract":"<p><p>CSF concentrations of β-amyloid 42 (Aβ42) and phosphorylated tau (p-tau) are well-established biomarkers of Alzheimer's disease and have been studied in relation to several neuropathological features both in patients and in cognitively unimpaired individuals. The CSF p-tau/Aβ42 ratio, a biomarker combining information from both pathophysiological processes, has emerged as a promising tool for monitoring disease progression, even at pre-clinical stages. Here, we studied the association between the CSF p-tau/Aβ42 ratio with downstream markers of pre-clinical Alzheimer's disease progression including brain structure, glucose metabolism, fibrillary Aβ deposition and cognitive performance in 234 cognitively unimpaired individuals, who underwent cognitive testing, a lumbar puncture, MRI, 18F-fluorodeoxyglucose and 18F-flutemetamol PET scanning. We evaluated both main effects and interactions with Alzheimer's disease risk factors, such as older age, female sex and the apoliporoptein E (<i>APOE</i>)-ɛ4 allele, in <i>a priori</i> defined regions of interest and further examined the associations on the whole-brain using voxel-wise regressions. In addition, as the association between CSF Alzheimer's disease biomarkers and brain structure and function may be non-linear, we tested the interaction between the CSF p-tau/Aβ42 ratio and stages of pre-clinical Alzheimer's disease defined using the amyloid (A) and tau (T) classification. We found significantly positive associations between CSF p-tau/Aβ42 and both cortical Aβ deposition and regional grey matter volume while no effect was observed for brain metabolism. A significant interaction with age indicated that, for the same level of CSF p-tau/Aβ42, older individuals displayed both increased Aβ deposition and lower grey matter volume, in widespread cortical areas. In addition, we found that women compared with men had a greater Aβ fibrillary accumulation in midline cortical areas and inferior temporal regions, for the same level of the CSF biomarker. The impact of CSF p-tau/Aβ42 on grey matter volume was modulated by AT stages, with A+T+ individuals displaying significantly less positive associations in areas of early atrophy in the Alzheimer's continuum. Finally, we found that sex and <i>APOE</i>-ɛ4 modulated the association between the CSF biomarker and episodic memory as well as abstract reasoning, respectively. Our data indicate that the CSF p-tau/Aβ42 ratio is strongly associated with multiple downstream neuropathological events in cognitively unimpaired individuals and may thus serve as a potent biomarker to investigate the earliest changes in pre-clinical Alzheimer's disease. Given that its impact on both Aβ deposition and grey matter volume is modulated by specific risk factors, our results highlight the need to take into account such predisposing variables in both clinical practice and prevention trials.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"7 1","pages":"fcae451"},"PeriodicalIF":4.1,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11668178/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142901227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-13eCollection Date: 2024-01-01DOI: 10.1093/braincomms/fcae429
Jochum J van 't Hooft, Willem L Hartog, Michelle Braun, Dewi Boessen, Jay L P Fieldhouse, Marie-Paule E van Engelen, Ellen H Singleton, Artur C Jaschke, Rebecca S Schaefer, Vikram Venkatraghavan, Frederik Barkhof, Argonde C van Harten, Flora H Duits, Sigfried N T M Schouws, Mardien L Oudega, Jason D Warren, Betty M Tijms, Yolande A L Pijnenburg
<p><p>Human musicality might have co-evolved with social cognition abilities, but common neuroanatomical substrates remain largely unclear. In behavioural variant frontotemporal dementia, social cognitive abilities are profoundly impaired, whereas these are typically spared in Alzheimer's disease. If musicality indeed shares a neuroanatomical basis with social cognition, it could be hypothesized that clinical and neuroanatomical associations of musicality and social cognition should differ between these causes of dementia. We recruited 73 participants from the Amsterdam Dementia Cohort (<i>n</i> = 30 female; aged 50-78), of whom 23 had behavioural variant frontotemporal dementia, 22 Alzheimer's disease and 28 were healthy controls. Musicality was assessed using a music-emotion recognition test, melody, tempo, accent and tuning subscores, a musicality summed score, the identification of auditory hedonic phenotypes and music emotion induction using skin conductance responses. Social cognition was assessed across multiple levels, including emotion recognition, theory of mind, socio-emotional sensitivity and understanding of social norms. We used ANCOVA to investigate subgroup differences in musicality and social cognition and linear regressions to investigate associations between musicality and social cognition. All analyses were adjusted for age, sex, musical training and mini mental state examination. Finally, we performed voxel-based morphometry analyses on T<sub>1</sub>-weighted MRI to study whether regions for musicality and social cognition overlapped anatomically. We found that patients with behavioural variant frontotemporal dementia performed worse on music-emotion recognition (all <i>P</i> < 0.001) and tempo recognition (all <i>P</i> < 0.05) compared with Alzheimer's disease and on musicality summed score (all <i>P</i> = 0.02) compared to controls only. Furthermore, patients with behavioural variant frontotemporal dementia had lower mean skin conductance responses during emotion-inducing music, compared to Alzheimer's disease (all <i>P</i> < 0.045). Worse music emotion recognition scores were associated with worse facial emotion recognition (<i>P</i> < 0.0001), worse theory of mind (<i>P</i> = 0.0005) and worse understanding of social norms (<i>P</i> = 0.01). Melody and tempo recognition were associated with facial emotion recognition and theory of mind, and accent recognition was associated with the theory of mind. Music emotion recognition and tempo recognition were also associated with executive functions. Worse music emotion recognition, melody recognition, tempo recognition, facial emotion recognition and theory of mind scores were all related to atrophy in the anterior temporal regions and the fusiform gyri, which play a role in multisensory integration, and worse tempo recognition was associated with atrophy of the anterior cingulate cortex. These results support the idea that musicality and social cognition may share a neurobiologi
{"title":"Musicality and social cognition in dementia: clinical and anatomical associations.","authors":"Jochum J van 't Hooft, Willem L Hartog, Michelle Braun, Dewi Boessen, Jay L P Fieldhouse, Marie-Paule E van Engelen, Ellen H Singleton, Artur C Jaschke, Rebecca S Schaefer, Vikram Venkatraghavan, Frederik Barkhof, Argonde C van Harten, Flora H Duits, Sigfried N T M Schouws, Mardien L Oudega, Jason D Warren, Betty M Tijms, Yolande A L Pijnenburg","doi":"10.1093/braincomms/fcae429","DOIUrl":"10.1093/braincomms/fcae429","url":null,"abstract":"<p><p>Human musicality might have co-evolved with social cognition abilities, but common neuroanatomical substrates remain largely unclear. In behavioural variant frontotemporal dementia, social cognitive abilities are profoundly impaired, whereas these are typically spared in Alzheimer's disease. If musicality indeed shares a neuroanatomical basis with social cognition, it could be hypothesized that clinical and neuroanatomical associations of musicality and social cognition should differ between these causes of dementia. We recruited 73 participants from the Amsterdam Dementia Cohort (<i>n</i> = 30 female; aged 50-78), of whom 23 had behavioural variant frontotemporal dementia, 22 Alzheimer's disease and 28 were healthy controls. Musicality was assessed using a music-emotion recognition test, melody, tempo, accent and tuning subscores, a musicality summed score, the identification of auditory hedonic phenotypes and music emotion induction using skin conductance responses. Social cognition was assessed across multiple levels, including emotion recognition, theory of mind, socio-emotional sensitivity and understanding of social norms. We used ANCOVA to investigate subgroup differences in musicality and social cognition and linear regressions to investigate associations between musicality and social cognition. All analyses were adjusted for age, sex, musical training and mini mental state examination. Finally, we performed voxel-based morphometry analyses on T<sub>1</sub>-weighted MRI to study whether regions for musicality and social cognition overlapped anatomically. We found that patients with behavioural variant frontotemporal dementia performed worse on music-emotion recognition (all <i>P</i> < 0.001) and tempo recognition (all <i>P</i> < 0.05) compared with Alzheimer's disease and on musicality summed score (all <i>P</i> = 0.02) compared to controls only. Furthermore, patients with behavioural variant frontotemporal dementia had lower mean skin conductance responses during emotion-inducing music, compared to Alzheimer's disease (all <i>P</i> < 0.045). Worse music emotion recognition scores were associated with worse facial emotion recognition (<i>P</i> < 0.0001), worse theory of mind (<i>P</i> = 0.0005) and worse understanding of social norms (<i>P</i> = 0.01). Melody and tempo recognition were associated with facial emotion recognition and theory of mind, and accent recognition was associated with the theory of mind. Music emotion recognition and tempo recognition were also associated with executive functions. Worse music emotion recognition, melody recognition, tempo recognition, facial emotion recognition and theory of mind scores were all related to atrophy in the anterior temporal regions and the fusiform gyri, which play a role in multisensory integration, and worse tempo recognition was associated with atrophy of the anterior cingulate cortex. These results support the idea that musicality and social cognition may share a neurobiologi","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"6 6","pages":"fcae429"},"PeriodicalIF":4.1,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11642622/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142830998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-13eCollection Date: 2024-01-01DOI: 10.1093/braincomms/fcae401
Laurent Sheybani
Associate Editor Laurent Sheybani discusses how artificial intelligence (AI) could be both a risk and a solution for statistical reliability in scientific research in the context of the European Union AI act, which came into force in the summer of 2024.
{"title":"Could AI safeguard us from AI?","authors":"Laurent Sheybani","doi":"10.1093/braincomms/fcae401","DOIUrl":"10.1093/braincomms/fcae401","url":null,"abstract":"<p><p>Associate Editor Laurent Sheybani discusses how artificial intelligence (AI) could be both a risk and a solution for statistical reliability in scientific research in the context of the European Union AI act, which came into force in the summer of 2024.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"6 6","pages":"fcae401"},"PeriodicalIF":4.1,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11644472/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142830986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-11eCollection Date: 2024-01-01DOI: 10.1093/braincomms/fcae387
[This corrects the article DOI: 10.1093/braincomms/fcad247.].
[更正文章DOI: 10.1093/braincomms/fcad247.]。
{"title":"Correction to: Revisiting anti-Hu paraneoplastic autoimmunity: phenotypic characterization and cancer diagnosis.","authors":"","doi":"10.1093/braincomms/fcae387","DOIUrl":"https://doi.org/10.1093/braincomms/fcae387","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.1093/braincomms/fcad247.].</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"6 6","pages":"fcae387"},"PeriodicalIF":4.1,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11631557/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142815267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-11eCollection Date: 2024-01-01DOI: 10.1093/braincomms/fcae449
William Matchin, Zeinab K Mollasaraei, Leonardo Bonilha, Christopher Rorden, Gregory Hickok, Dirk den Ouden, Julius Fridriksson
Syntactic processing and verbal working memory are both essential components to sentence comprehension. Nonetheless, the separability of these systems in the brain remains unclear. To address this issue, we performed causal-inference analyses based on lesion and connectome network mapping using MRI and behavioural testing in two groups of individuals with chronic post-stroke aphasia. We employed a rhyme judgement task with heavy working memory load without articulatory confounds, controlling for the overall ability to match auditory words to pictures and to perform a metalinguistic rhyme judgement, isolating the effect of working memory load (103 individuals). We assessed non-canonical sentence comprehension, isolating syntactic processing by incorporating residual rhyme judgement performance as a covariate for working memory load (78 individuals). Voxel-based lesion analyses and structural connectome-based lesion symptom mapping controlling for total lesion volume were performed, with permutation testing to correct for multiple comparisons (4000 permutations). We observed that effects of working memory load localized to dorsal stream damage: posterior temporal-parietal lesions and frontal-parietal white matter disconnections. These effects were differentiated from syntactic comprehension deficits, which were primarily associated with ventral stream damage: lesions to temporal lobe and temporal-parietal white matter disconnections, particularly when incorporating the residual measure of working memory load as a covariate. Our results support the conclusion that working memory and syntactic processing are associated with distinct brain networks, largely loading onto dorsal and ventral streams, respectively.
{"title":"Verbal working memory and syntactic comprehension segregate into the dorsal and ventral streams, respectively.","authors":"William Matchin, Zeinab K Mollasaraei, Leonardo Bonilha, Christopher Rorden, Gregory Hickok, Dirk den Ouden, Julius Fridriksson","doi":"10.1093/braincomms/fcae449","DOIUrl":"10.1093/braincomms/fcae449","url":null,"abstract":"<p><p>Syntactic processing and verbal working memory are both essential components to sentence comprehension. Nonetheless, the separability of these systems in the brain remains unclear. To address this issue, we performed causal-inference analyses based on lesion and connectome network mapping using MRI and behavioural testing in two groups of individuals with chronic post-stroke aphasia. We employed a rhyme judgement task with heavy working memory load without articulatory confounds, controlling for the overall ability to match auditory words to pictures and to perform a metalinguistic rhyme judgement, isolating the effect of working memory load (103 individuals). We assessed non-canonical sentence comprehension, isolating syntactic processing by incorporating residual rhyme judgement performance as a covariate for working memory load (78 individuals). Voxel-based lesion analyses and structural connectome-based lesion symptom mapping controlling for total lesion volume were performed, with permutation testing to correct for multiple comparisons (4000 permutations). We observed that effects of working memory load localized to dorsal stream damage: posterior temporal-parietal lesions and frontal-parietal white matter disconnections. These effects were differentiated from syntactic comprehension deficits, which were primarily associated with ventral stream damage: lesions to temporal lobe and temporal-parietal white matter disconnections, particularly when incorporating the residual measure of working memory load as a covariate. Our results support the conclusion that working memory and syntactic processing are associated with distinct brain networks, largely loading onto dorsal and ventral streams, respectively.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"6 6","pages":"fcae449"},"PeriodicalIF":4.1,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11660927/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142878400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-10eCollection Date: 2025-01-01DOI: 10.1093/braincomms/fcae447
Marina Romozzi, Serena Spartano, Federica Francesca L'Erario, Luigi Francesco Iannone, Vincenzo Trigila, Annalisa Gentile, Pasquale Sanginario, Paolo Calabresi, Francesco Danilo Tiziano, Catello Vollono
Familial hemiplegic migraine type 2 results from pathogenic variants in the ATP1A2 gene, which encodes for a catalytic subunit of sodium/potassium ATPase. This extremely rare autosomal dominant disorder manifests with a spectrum of symptoms, most commonly pure hemiplegic phenotype, epilepsy, and/or intellectual disability. In this study, we detail the clinical features and genetic analysis of nine patients from a large family spanning four generations, with all carrying a previously unreported likely pathogenic variant, p.Gly615Glu, in ATP1A2, compatible with a diagnosis of familial hemiplegic migraine type 2, fully penetrant with variable expressivity. This newly identified likely pathogenic variant primarily presented with psychiatric disturbances and a non-hemiplegic phenotype. Only one patient presented hemiplegic attacks, while seven were diagnosed with migraine with aura, including visual, sensory, and speech/language aura, and one with migraine without aura. The identification of the genes responsible for the more common forms of migraine, both with and without aura, remains a significant challenge in migraine genetics and is critical for advancing personalized medicine.
{"title":"Clinical characterization of a novel <i>ATP1A2</i> p.Gly615Glu mutation in nine family members with familial hemiplegic migraine.","authors":"Marina Romozzi, Serena Spartano, Federica Francesca L'Erario, Luigi Francesco Iannone, Vincenzo Trigila, Annalisa Gentile, Pasquale Sanginario, Paolo Calabresi, Francesco Danilo Tiziano, Catello Vollono","doi":"10.1093/braincomms/fcae447","DOIUrl":"10.1093/braincomms/fcae447","url":null,"abstract":"<p><p>Familial hemiplegic migraine type 2 results from pathogenic variants in the <i>ATP1A2</i> gene, which encodes for a catalytic subunit of sodium/potassium ATPase. This extremely rare autosomal dominant disorder manifests with a spectrum of symptoms, most commonly pure hemiplegic phenotype, epilepsy, and/or intellectual disability. In this study, we detail the clinical features and genetic analysis of nine patients from a large family spanning four generations, with all carrying a previously unreported likely pathogenic variant, p.Gly615Glu, in <i>ATP1A2</i>, compatible with a diagnosis of familial hemiplegic migraine type 2, fully penetrant with variable expressivity. This newly identified likely pathogenic variant primarily presented with psychiatric disturbances and a non-hemiplegic phenotype. Only one patient presented hemiplegic attacks, while seven were diagnosed with migraine with aura, including visual, sensory, and speech/language aura, and one with migraine without aura. The identification of the genes responsible for the more common forms of migraine, both with and without aura, remains a significant challenge in migraine genetics and is critical for advancing personalized medicine.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"7 1","pages":"fcae447"},"PeriodicalIF":4.1,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11668175/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142901219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-09eCollection Date: 2025-01-01DOI: 10.1093/braincomms/fcae440
Romain Dalléry, Nicolas Fraisse, Laurent Cléret de Langavant, Katia Youssov, Graça Morgado, Renaud Massart, Robin Schubert, Ralf Reilmann, Charlotte Jacquemot, Blanche Bapst, Monica Busse, David Craufurd, Anne Rosser, Marine Lunven, Anne-Catherine Bachoud-Lévi
The prevalent belief that individuals with Huntington's disease exhibit selfish behaviour, disregarding the thoughts, feelings and actions of others, has been challenged by patient organizations and clinical experts. To further investigate this issue and study whether participants with Huntington's disease can pay attention to others, a joint memory task was carried out in patients with Huntington's disease with and without a partner. This study involved 69 participants at an early stage of Huntington's disease and 56 healthy controls from the UK, France and Germany, who participated in the international Repair-HD multicentre study (NCT03119246). Participants completed a semantic categorization task across three categories: animals, fruits and vegetables and manufactured objects. They performed the task either alone (Alone condition) or with the examiner acting as a partner (Pair condition). In the Pair condition, the participant was assigned one category, their partner was assigned another and one category was left unassigned. Afterwards, participants engaged in a surprise free recall task to remember as many words as possible. Words not assigned to anyone were considered socially irrelevant in contrast to the ones assigned to the participant and to the partner. Both groups demonstrated the expected self-prioritization effect, recalling their assigned words better than their partner's or unassigned words in both conditions. Additionally, a joint memory effect was observed, with better recall for the partner's assigned words than the unassigned words in the Pair condition (controls: difference = 0.45, P < 0.001; participants with Huntington's disease: difference = 0.34, P < 0.001). Socially relevant words were thus better recalled than irrelevant words. The number of recalled words correlated with cognitive performance (all P-values < 0.05) and MRI analysis revealed a negative correlation between the joint memory effect and right orbitofrontal grey matter density in participants with Huntington's disease. These findings challenge the notion that individuals with Huntington's disease display selfish behaviours because of disinterest in others. They show the ability to process information about their partners, implying that their social difficulties may arise from factors other than social cognition deficits. This opens the door for more ecological assessments of social cognition in patients with Huntington's disease.
{"title":"The joint memory effect: challenging the selfish stigma in Huntington's disease?","authors":"Romain Dalléry, Nicolas Fraisse, Laurent Cléret de Langavant, Katia Youssov, Graça Morgado, Renaud Massart, Robin Schubert, Ralf Reilmann, Charlotte Jacquemot, Blanche Bapst, Monica Busse, David Craufurd, Anne Rosser, Marine Lunven, Anne-Catherine Bachoud-Lévi","doi":"10.1093/braincomms/fcae440","DOIUrl":"10.1093/braincomms/fcae440","url":null,"abstract":"<p><p>The prevalent belief that individuals with Huntington's disease exhibit selfish behaviour, disregarding the thoughts, feelings and actions of others, has been challenged by patient organizations and clinical experts. To further investigate this issue and study whether participants with Huntington's disease can pay attention to others, a joint memory task was carried out in patients with Huntington's disease with and without a partner. This study involved 69 participants at an early stage of Huntington's disease and 56 healthy controls from the UK, France and Germany, who participated in the international Repair-HD multicentre study (NCT03119246). Participants completed a semantic categorization task across three categories: animals, fruits and vegetables and manufactured objects. They performed the task either alone (Alone condition) or with the examiner acting as a partner (Pair condition). In the Pair condition, the participant was assigned one category, their partner was assigned another and one category was left unassigned. Afterwards, participants engaged in a surprise free recall task to remember as many words as possible. Words not assigned to anyone were considered socially irrelevant in contrast to the ones assigned to the participant and to the partner. Both groups demonstrated the expected self-prioritization effect, recalling their assigned words better than their partner's or unassigned words in both conditions. Additionally, a joint memory effect was observed, with better recall for the partner's assigned words than the unassigned words in the Pair condition (controls: difference = 0.45, <i>P</i> < 0.001; participants with Huntington's disease: difference = 0.34, <i>P</i> < 0.001). Socially relevant words were thus better recalled than irrelevant words. The number of recalled words correlated with cognitive performance (all <i>P</i>-values < 0.05) and MRI analysis revealed a negative correlation between the joint memory effect and right orbitofrontal grey matter density in participants with Huntington's disease. These findings challenge the notion that individuals with Huntington's disease display selfish behaviours because of disinterest in others. They show the ability to process information about their partners, implying that their social difficulties may arise from factors other than social cognition deficits. This opens the door for more ecological assessments of social cognition in patients with Huntington's disease.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"7 1","pages":"fcae440"},"PeriodicalIF":4.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11693399/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142916573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-09eCollection Date: 2024-01-01DOI: 10.1093/braincomms/fcae438
Isaac Llorente-Saguer, Neil P Oxtoby
PET is used to measure tau protein accumulation in Alzheimer's disease. Multiple biomarkers have been proposed to track disease progression, most notably the standardized uptake value ratio of PET tracer uptake in a target region of interest relative to a reference region, but literature suggests these region choices are nontrivial. This study presents and evaluates a novel framework, BioDisCVR, designed to facilitate the discovery of useful biomarkers, demonstrated on [18F]AV-1451 tau PET data in multiple cohorts. BioDisCVR enhances signal-to-noise by conducting a data-driven search through the space of possible combinations of regional tau PET signals into a ratio of two composite regions, driven by a user-defined fitness function. This study compares ratio-based biomarkers discovered by the framework with state-of-the-art standardized uptake value ratio biomarkers. Data used is tau PET regional measurements from 198 individuals from the Alzheimer's Disease Neuroimaging Initiative database, used for discovery, and 42 from the Mayo Clinic Alzheimer's Disease Research Center and Mayo Clinic Study of Aging (MCSA), used for external validation. Biomarkers are evaluated by calculating clinical trial sample size estimates for 80% power and 20% effect size. Secondary metrics are a measure of longitudinal consistency (standard deviation of linear mixed-effects model residuals), and separation between cognitive groups (t-statistic of the change over time due to being cognitively impaired). When applied to preclinical (secondary prevention with CU individuals) and clinical (treatment aimed at cognitively impaired individuals) trials on Alzheimer's disease, our data-driven framework BioDisCVR discovered ratio-based tau PET biomarkers vastly superior to previous work, both reducing measurement error and sample size estimates for hypothetical clinical trials. Our analysis suggests remarkable potential for patient benefit (reduced exposure to health risks associated with experimental drugs) and substantial cost savings, through accelerated trials and reduced sample sizes. Our study supports the leveraging of data-driven methods like BioDisCVR for clinical benefit, with the potential to positively impact drug development in Alzheimer's disease and beyond.
PET用于测量阿尔茨海默病中tau蛋白的积累。已经提出了多种生物标志物来跟踪疾病进展,最值得注意的是PET示踪剂在目标区域相对于参考区域的摄取的标准化摄取值比,但文献表明这些区域的选择不是微不足道的。本研究提出并评估了一个新的框架,BioDisCVR,旨在促进发现有用的生物标志物,在多个队列的AV-1451 tau PET数据中得到了证明。BioDisCVR通过对区域tau PET信号可能组合的空间进行数据驱动搜索,从而增强信噪比,并由用户定义的适应度函数驱动。本研究将该框架发现的基于比率的生物标志物与最先进的标准化摄取值比率生物标志物进行了比较。使用的数据是来自阿尔茨海默病神经影像学倡议数据库的198名个体的tau PET区域测量数据,用于发现,以及来自梅奥诊所阿尔茨海默病研究中心和梅奥诊所衰老研究(MCSA)的42名个体,用于外部验证。通过计算80%功效和20%效应量的临床试验样本量来评估生物标志物。次要指标是纵向一致性(线性混合效应模型残差的标准偏差)和认知组之间的分离(由于认知受损而随时间变化的t统计量)的度量。当应用于阿尔茨海默病的临床前(CU个体的二级预防)和临床(针对认知受损个体的治疗)试验时,我们的数据驱动框架BioDisCVR发现了基于比率的tau PET生物标志物,大大优于以前的工作,既减少了假设临床试验的测量误差,也减少了样品量估计。我们的分析表明,通过加速试验和减少样本量,患者获益(减少与实验性药物相关的健康风险)和大量节约成本的潜力显著。我们的研究支持利用像BioDisCVR这样的数据驱动方法来获得临床益处,并有可能对阿尔茨海默病及其他疾病的药物开发产生积极影响。
{"title":"A data-driven framework for biomarker discovery applied to optimizing modern clinical and preclinical trials on Alzheimer's disease.","authors":"Isaac Llorente-Saguer, Neil P Oxtoby","doi":"10.1093/braincomms/fcae438","DOIUrl":"10.1093/braincomms/fcae438","url":null,"abstract":"<p><p>PET is used to measure tau protein accumulation in Alzheimer's disease. Multiple biomarkers have been proposed to track disease progression, most notably the standardized uptake value ratio of PET tracer uptake in a target region of interest relative to a reference region, but literature suggests these region choices are nontrivial. This study presents and evaluates a novel framework, BioDisCVR, designed to facilitate the discovery of useful biomarkers, demonstrated on [<sup>18</sup>F]AV-1451 tau PET data in multiple cohorts. BioDisCVR enhances signal-to-noise by conducting a data-driven search through the space of possible combinations of regional tau PET signals into a ratio of two composite regions, driven by a user-defined fitness function. This study compares ratio-based biomarkers discovered by the framework with state-of-the-art standardized uptake value ratio biomarkers. Data used is tau PET regional measurements from 198 individuals from the Alzheimer's Disease Neuroimaging Initiative database, used for discovery, and 42 from the Mayo Clinic Alzheimer's Disease Research Center and Mayo Clinic Study of Aging (MCSA), used for external validation. Biomarkers are evaluated by calculating clinical trial sample size estimates for 80% power and 20% effect size. Secondary metrics are a measure of longitudinal consistency (standard deviation of linear mixed-effects model residuals), and separation between cognitive groups (<i>t</i>-statistic of the change over time due to being cognitively impaired). When applied to preclinical (secondary prevention with CU individuals) and clinical (treatment aimed at cognitively impaired individuals) trials on Alzheimer's disease, our data-driven framework BioDisCVR discovered ratio-based tau PET biomarkers vastly superior to previous work, both reducing measurement error and sample size estimates for hypothetical clinical trials. Our analysis suggests remarkable potential for patient benefit (reduced exposure to health risks associated with experimental drugs) and substantial cost savings, through accelerated trials and reduced sample sizes. Our study supports the leveraging of data-driven methods like BioDisCVR for clinical benefit, with the potential to positively impact drug development in Alzheimer's disease and beyond.</p>","PeriodicalId":93915,"journal":{"name":"Brain communications","volume":"6 6","pages":"fcae438"},"PeriodicalIF":4.1,"publicationDate":"2024-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11632366/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142815263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}