Biology subjects

Li, Q.

Publications and source records attributed to Li, Q..

At least 181 records · Page 10Linked to original sources

bioRxiv2025

NQO1 phase condensation promotes stress granule assembly to facilitate pancreatic carcinogenesis

G3BP1 promotes pancreatic ductal adenocarcinoma (PDAC) tumorigenesis driven by oncogenic KRAS mutations through liquid-liquid phase separation (LLPS)-mediated assembly of stress granules (SGs). However, the regulatory mechanisms remain elusive. We identify the antioxidant enzyme NAD(P)H quinone dehydrogenase 1 (NQO1) as a novel SG regulator that enhances SG assembly in pancreatic cancer cells independently of reactive oxygen species (ROS). Mechanistic studies reveal that NQO1 does not regulate the expression of G3BP1 or other SG-associated genes. Instead, NQO1 undergoes LLPS dependent on its RNA-binding K homology (KH) like domain. Further analysis demonstrates that residues 121-131 of NQO1 directly interact with G3BP1s RNA-binding domain (RBD), enhancing the multivalency of G3BP1 complexes to potentiate LLPS-driven SG assembly. This interaction accelerates cell proliferation, KRAS mutation-induced acinar-to-ductal metaplasia (ADM), and pancreatic carcinogenesis. Notably, the interaction between NQO1 residues 121-131 and G3BP1s RBD is essential for NQO1 phase condensation under stress condition. Integrative analysis of human PDAC transcriptomic datasets reveals a weak association between NQO1 and G3BP1 levels. Importantly, both NQO1 and G3BP1 formed biological condensates and co-localized in the lesions of human PDAC tissue sections. Our study uncovers a novel KRAS mutation-driven mechanism of pancreatic carcinogenesis through the lens of phase separation, transcending conventional gene expression regulation and offering new insights into non-canonical KRAS-NQO1-G3BP1-SG regulatory networks in PDAC initiation.

cancer biology↗

bioRxiv2025

Study on Early pregnancy diagnosis in sows based on joint analysis of vaginal secretion metabolomics and machine learning

ObjectiveMetabolic transformations in female mammals throughout gestation manifest in the metabolite profiles of bodily fluids, potentially serving as biomarkers for the diagnosis of pregnancy. This investigation concentrated on sows 18 days post-mating, with the objective of identifying biomarkers pertinent to early pregnancy diagnosis through the analysis of variations in metabolic molecules within vaginal secretions. MethodsVaginal secretion samples were procured from both pregnant and non-pregnant sows 18 days post-mating, subsequently subjected to untargeted metabolomic analysis utilizing liquid chromatography-mass spectrometry (LC-MS). The samples were partitioned into training and testing datasets, and machine learning algorithms--specifically, Random Forest (RF) and support vector machine (SVM)--were integrated with metabolite weight ranking to identify key biological markers. ResultsA total of 3,249 metabolic molecules were identified, among which 534 exhibited significant differential expression in the vaginal secretions of pregnant versus non-pregnant sows. Notably, three hormones that correlate with the pregnant status of the sow were discerned: Progesterone, 3-Deoxyestradiol, and Prostaglandin E1. KEGG pathway analysis revealed that the differentially expressed metabolites were predominantly enriched in nucleotide metabolic pathways. The RF model demonstrated an impressive accuracy of 1.00 in the training dataset and 0.88 in the testing dataset, while the SVM model maintained an accuracy of 1.00 across both datasets. Utilizing model weights and differential expression data, three pivotal metabolites were identified: Indolepropionic acid, cis-Aconitate, and 4-p-Coumaroylquinic acid, which exhibited ROC curve AUC values of 0.90, 0.89, and 0.79, respectively. ConclusionThis study validates the viability of utilizing vaginal secretions for the early diagnosis of pregnancy in sows, thereby establishing a foundation for the advancement of non-invasive diagnostic methodologies.

zoology↗

bioRxiv2025

Deciphering acquired resistance mechanisms to sustained auxin-inducible protein degradation in cells and mice

Targeted protein degradation is a favorable strategy for studying the immediate downstream effects of protein loss-of-function. An appealing platform among these technologies is the auxin-inducible degron (AID) system. Although this system has been applied extensively to cell and animal models, degradation resistance to long-term auxin treatment has not been studied. With the advent of the new AID2 system, cellular toxicity due to the high concentrations of auxin required in the original AID1 system is no longer a concern, making it possible to study protein degradation over extended periods. In this study, we derived multiple miniAID-tagged knock-in human cell lines and a Ctcf-miniAID knock-in mouse strain to investigate mechanisms of degradation resistance. We revealed four independent resistance mechanisms, including a nonsense mutation in the CTCF coding sequence that removed the miniAID peptide, a missense point mutation in the miniAID coding region that disrupted ubiquitin complex targeting, and silencing of the OsTIR1 adaptor protein. Resistance to auxin degradation was also acquired in mouse primary CtcfminiAID/miniAID knock-in B-ALL cells through missense mutations of the OsTIR1(F74G) protein in vivo and ex vivo. In summary, our innovative study expands our understanding of the AID system and cautions careful consideration of design for future applications in mammalian system.

cell biology↗

bioRxiv2025

PhaseICA: Complex-Valued Decomposition of Spatially Independent Brain Waves

Understanding complex dynamics from spatiotemporal signals requires robust tools capable of decoding reoccurring patterns. Traditional ICA methods often overlook the spatially non-stationarity nature of brain activity across both the frequency and spatial domains. We propose a novel data-driven approach, named PhaseICA, designed to extract reoccurring spatiotemporal patterns, referred to as brain waves. Unlike conventional ICA methods that focus solely on amplitude, PhaseICA incorporates phase information directly into the component estimation, preserving the nonstationary property that real-valued ICA methods typically discard. The method performs spatial independence optimization in the complex domain by minimizing a complex entropy bound over the eigenvectors of Hilbert-transformed signals. The proposed method captures spatial propagation across brain regions with interpretable and compact representations, offering a promising foundation for decoding brain dynamic systems and revealing the temporal relationship of regions.

neuroscience↗

bioRxiv2025

Lower Airway Dysbiosis in NTM+ Bronchiectasis is Associated with NET-Predominant Severe Phenotypes

RationaleThe discoveries of neutrophilic inflammation and Pseudomonas-dominant pulmonary dysbiosis have helped pave the way for host-directed therapy in bronchiectasis. Substantial knowledge gaps remain about the interplay between neutrophilic signatures and microbes in non-tuberculous mycobacterial lung disease (NTM-LD), a phenotypically diverse lung infection that is increasingly prevalent in the United States and other parts of the world. ObjectivesEvaluate the lower airway microbiota and neutrophilic traits in NTM- and NTM+ bronchiectasis. Methods16S rRNA gene sequencing, cell counts and neutrophil extracellular trap (NET) immunoassays were performed on bronchoscopic lower airway samples in 200 bronchiectasis subjects (108 NTM-, 92 NTM+). A preclinical model of oral commensal micro-aspiration and NTM infection was used to profile the murine lower airways with flow cytometry and a NET assay. Measurements and Main ResultsLower airways of NTM+ bronchiectasis patients were enriched with Mycobacterium and oral commensals (e.g., Veillonella, Prevotella). NET levels were higher in NTM+ BAL. Mycobacterium and oral commensals co-occurred with NET and neutrophils in network studies. Distinct oral commensal taxa associated with severe disease phenotypes such as cavitary disease and exacerbators. In a murine micro-aspiration model, the combination of oral commensals and Mycobacterium led to a sustained pro-inflammatory immune response marked by an increase in Th17, {gamma}8T cells, PD-1+ T lymphocytes as well as higher NET levels. ConclusionsOur analyses showed that distinct microbiome features beyond the primary pathogen can contribute to neutrophilic inflammation and severe disease phenotypes in bronchiectasis/ NTM-LD.

immunology↗

bioRxiv2025

Longitudinal analysis of bacterial community dynamics in normal hospital ward following patient occupancy

The hospital microbiome significantly influences patient recovery and clinical outcomes. However, the dynamics of microbial colonization and transmission following initial patient occupancy remain poorly understood. Here, we employed 16S rRNA gene amplicon sequencing to investigate bacterial community dynamics on surfaces within neurosurgery ward and patients as a new hospital became operational. Our results showed that bacterial colonization in hospital wards follows distinct site-specific patterns, after hospital opening, alpha diversity was significantly increased on floors and drawer handles but decreased on bedrails and faucet handles compared to preopening. Beta diversity analysis showed that surfaces frequently contacted by patients exhibited the greatest compositional turnover, such as bedrails, drawer handles, and faucet handles, bacterial communities in after-opening were more homogeneous across sites than preopening, indicating potential bacterial transmission. Moreover, we found following patient admission, patient hand-derived microbiomes exert a significant influence on the bacterial communities in hospital wards, with a particularly pronounced impact on bedrails. Additionally, the potential disease risk of bedrails in post-opening was significantly higher than preopening. Taken together, these findings underscore the critical role of human contact in shaping hospital microbiomes and highlight the importance of targeted infection control strategies to mitigate pathogen transmission.

bioinformatics↗

bioRxiv2025

DynPerturb:Dynamic Perturbation Modeling for Spatiotemporal Single-Cell Systems

Perturbation responses in multicellular systems are inherently spatiotemporal, governed by temporal dynamics, perturbation intensity, and tissue context. However, existing approaches rarely capture explicit spatiotemporal perturbation dynamics, limiting the ability to reconstruct how perturbations propagate over time, spread across space, and induce feedback at multiple biological scales. Here we introduce DynPerturb, a dynamic inference framework for single-cell and spatial transcriptomics that systematically models the "when-how strong-where" dimensions of perturbations. DynPerturb incorporates temporal encoding, spatial adjacency, and memory modules to capture nonlinear signal propagation and cross-regional feedback with mechanistic interpretability. Across temporal benchmarking datasets, DynPerturb consistently outperformed existing methods in regulatory link prediction, demonstrated zero-shot generalization to unseen nodes, and preserved accuracy under varying sparsity conditions and temporal resolutions. Applied to representative biological systems, DynPerturb uncovers dynamic regulatory rewiring in kidney disease, highlighting a mid-age sensitivity window and potential reversibility with early intervention; delineated a temporal fate-switching boundary between megakaryocyte-erythroid progenitors (MEPs) and granulocyte-monocyte progenitors (GMPs) during hematopoiesis; and revealed spatiotemporal interchamber signaling in murine heart development, where Igf2 perturbations induced spatial feedback shaping chamber proportioning. Collectively, these results establish DynPerturb as a unified and versatile system for dissecting dynamic perturbation effects and guiding precision intervention strategies in multicellular systems.

bioinformatics↗

bioRxiv2025

DNA Data Storage Architecture via Ligation of Dynamic DNA Bytes

The explosive growth of digital data is overwhelming conventional storage media, creating an urgent need for more efficient solutions. DNA offers immense potential for digital data storage, yet most systems remain static and archival. Here, we present a modular DNA storage architecture based on dynamic DNA bytes (DynaBytes)-- pre-fabricated DNA segments that can be ligated into reconfigurable information units. Utilizing core, functional and control DynaBytes, we stored 210,776 bits (26,347 bytes) of digital information organized within a file-system, and demonstrated CRUD (Create-Read-Update-Delete)-like operations, hierarchical access and nanopore-based realtime retrieval. Robust data recovery was achieved under [~]100x error-prone sequencing using streamlined error correction and fuzzy decoding. By relying on in vitro ligation of standardized components, DynaBytes reduces cost, scales efficiently, and allows interactive, rewritable storage. These features advance DNA storage beyond passive archiving toward a reconfigurable framework, opening new possibilities for dynamic, practical and large-scale DNA-based data systems.

synthetic biology↗

bioRxiv2025

From ambiguous object to illusory faces: EEG decoding reveals a dynamic cascade of face pareidolia

Face pareidolia, perceiving faces in inanimate objects, provides a unique window into how the brain constructs perceptual meaning from ambiguous visual input. In this work, we investigated the neural dynamics of face pareidolia, testing the hypothesis that it emerges from a temporal cascade that integrates global (low spatial frequency, LSF) and local (high spatial frequency, HSF) visual information. With a pareidolia detection task, we combined event-related potentials (ERP), multivariate pattern analysis (MVPA), and representational similarity analysis (RSA) to map the evolving neural code for illusory face perception. Behaviorally, participants experienced pareidolia from both LSF and HSF stimuli, but the percept was strongest for broadband images containing both frequency bands. Electrophysiological results revealed a clear temporal progression. Early processing (<150 ms) was driven by low-level attributes, with distinct P100/N100 components and neural representations for LSF and HSF signals. A critical shift occurred around 145 ms, after which MVPA decoding could reliably distinguish between images perceived as faces and those that were not. Concurrently, RSA showed that the geometry of neural representations shifted to reflect participants subjective face-likeness ratings, rather than the initial physical properties of the stimuli. This transition to a higher-order, subjective evaluation was marked by a later N250 component, whose amplitude indexed the cognitive load of integrating the visual cues. Together, these findings demonstrate that face pareidolia is a dynamic neural cascade, from early sensory encoding to higher-order perceptual evaluation, driven by the integration of global configuration and local features of visual stimuli. Our results illuminate how the brain transforms ambiguous input into meaningful social perception, offering insight into the temporal dynamics of visual awareness.

neuroscience↗

bioRxiv2025

A neuroendocrine principle: Pancreatic islets actively shape sympathetic innervation

Survival critically depends on maintaining blood glucose levels to provide essential energy, especially during emergencies such as the fight-or-flight response, when timely glucose control via neural integration is vital. However, pancreatic islets constitute only a small fraction of the pancreas and are dispersed throughout the organ, raising the fundamental question of how the nervous system coordinates synchronized control of multiple islets. Using whole-organ clearing and 3D imaging, we mapped pancreatic sympathetic innervation, revealing specialized anatomical integration between sympathetic nerves and islets. Transplanted islets intrinsically attracted sympathetic nerves independent of their native environment. Chronic islet injury disrupted sympathetic innervation and markedly impaired nerve regeneration after denervation. Sympathetic denervation markedly elevated islet-derived Reg2 and Reg3{beta}; administration of these proteins accelerated sympathetic regeneration and improved islet graft function. Our findings identify an islet-sympathetic architecture actively maintained by islets, uncovering an endocrine-driven mechanism for neural regulation, highlighting Reg2 and Reg3{beta} as therapeutic candidates for diabetes management.

neuroscience↗

bioRxiv2025

Albumin-STING Nanocomplex Reprograms HSPCs to Antitumor Neutrophils with Enhanced MHC I Antigen Presentation for Cancer Immunotherapy

Tumor-associated immunosuppressive neutrophils, termed myeloid-derived suppressor cells (MDSCs), compromise cancer immunotherapy. They can be pathologically programmed as early the hematopoietic stem and progenitor cell (HSPC) stage by suppressing interferon signaling. Reprogramming HSPCs toward antitumor neutrophils through the stimulator of interferon genes (STING) activation offers a promising therapeutic strategy. Here, we demonstrate that an albumin-STING nanoagonist (Nano ZSA-51D) reprograms HSPCs to generate antitumor neutrophils, enhancing MHC I-mediated CD8 T cell immunity. Nano ZSA-51D activates STING-interferon signaling in HSPCs, promoting their expansion and differentiation toward granulocyte-monocyte progenitors via STING-NF-{kappa}B-IL-6 signaling. It further reprograms neutrophils into CD14ICAM-1+ subset through STING-NF-{kappa}B-TNF- signaling, enhancing tumor infiltration. These neutrophils upregulate interferon signaling and MHC I antigen presentation, boosting tumor-specific CD8 T cell responses. Adoptive transfer of Nano ZSA-51D-reprogrammed neutrophils with -PD1 therapy achieves complete colon tumor remission. Our findings provide a novel strategy to reprogram HSPCs toward antitumor neutrophils and highlight the potential of early interventions at HSPC stage to rewire neutrophil fate for cancer immunotherapy.

immunology↗

bioRxiv2025

Segmented poly(A) tails with microRNA target sites confer tissue-specific regulation for mRNA therapeutics

Targeted delivery and controlled expression of mRNA-LNPs are critical for the development of safe and effective mRNA medicines. However, efficient post-delivery regulation of mRNA-LNP expression remains challenging. In this study, we engineered segmented poly(A) tail variants that function as gene-specific regulatory elements for synthetic mRNAs. Specifically, we inserted microRNA target sites (MTS) for miR-122 or miR-142 at various positions of the poly(A) tail of synthesized luciferase reporter mRNA. These modifications significantly reduced luciferase expression in non-target tissues in vitro and in vivo, demonstrating position-dependent selective expression control. Furthermore, by incorporating triple-MTS sequences for miR-142, miR-126, and miR-148a in all possible combinations at the 5 end of the poly(A) tail, we identified triple-MTS arrangements that simultaneously decrease luciferase activities in three non-target hepatic cell types, while preserving robust expression in hepatocytes. The results highlighted the importance of MTS insertion order for optimal mRNA silencing. These triple-MTS modules significantly expanded the utility of single miRNA-responsive elements, enabling cell-type selective regulation for mRNA therapeutics. By complementing tissue-tropic delivery LNPs, our mRNA cargo regulatory elements have the potential to improve tissue and cell type selectivity as a novel platform for post-delivery regulation of mRNA-LNP.

bioengineering↗

bioRxiv2025

Evolutionary innovation within conserved gene regulatory networks underlying biomineralized skeletons in Bilateria

Biomineralized skeletons have evolved convergently across animals, yet exhibit remarkable diversity in structure and development. However, the evolutionary origins of gene regulatory networks underlying biomineralized skeletons remains elusive. Here, we report comprehensive developmental profiling of transcriptomic and chromatin dynamics in a bivalve mollusc, Crassostrea nippona. We provide evidence for a biphasic regulatory program orchestrating larval and adult shell formation, involving the coordinated activity of ancient transcription factors and dynamic chromatin remodeling. Comparative analyses suggest a conserved developmental toolkit was co-opted for larval exoskeleton formation in the common lophotrochozoan ancestor. In contrast, limited regulatory conservation was observed between lophotrochozoans and echinoderms with regards to the formation of biomineralized skeletons, despite both relying on a heterochronic activation of ancestral regulators. Together, our findings support a hierarchical model where dynamic chromatin decouples rapidly evolving effectors from deeply conserved regulators, allowing modular innovations within conserved gene regulatory networks. This study highlights how epigenetic dynamics bridge evolutionary conservation and novelty, offering a framework for understanding the independent evolution of biomineralization across Bilateria through combinatorial regulatory evolution.

evolutionary biology↗

bioRxiv2025

SARS-CoV-2 nucleocapsid induces hyperinflammation and vascular leakage through the Toll-like receptor signaling axis in macrophages

Tens of thousands of severe COVID-19 cases are hospitalized weekly in the U.S., often driven by an imbalance between antiviral responses and inflammatory signaling, leading to uncontrolled cytokine secretion. The SARS-CoV-2 nucleocapsid (N) protein is a known immune antagonist, but its role in macrophage-driven cytokine storms is unclear. We demonstrate that N functions in a pathway-specific manner, specifically amplifying nuclear factor {kappa}B-related transcripts upon Toll-like receptor 7/8 stimulation. Moreover, we show that this is a conserved feature of pathogenic coronaviruses, with the delta variant N being the most pro-inflammatory. Our interaction networks suggest the delta variant N drives inflammation through interactions with several stress granule-related proteins. Profiling of secreted cytokines revealed that supernatants from the delta variant N-expressing macrophages disrupt brain and heart endothelial barriers, implicating N in COVID-19-associated cognitive and cardiac complications. Our findings highlight N-mediated immune imbalance as a driver of severe COVID-19 and identify N as a promising therapeutic target to mitigate hyperinflammation.

microbiology↗

bioRxiv2025

Paclitaxel Alleviates Pulmonary Arterial Hypertension by Modulating Macrophage M2a Polarization via the NF-κB Pathway

BackgroundPulmonary arterial hypertension (PAH) is primarily associated with vascular remodeling, in which macrophage polarization is considered to play a major role. Paclitaxel(PTX) has been shown to modulate macrophage polarization in tumors. We investigated whether PTX could alleviate PAH by altering macrophage polarization, particularly M2a macrophages. MethodsTo establish PAH, rats underwent left pneumonectomy followed by monocrotaline (MCT) injection. In vitro, THP-1 cells were differentiated into macrophages using PMA and polarized with LPS+IFN-{gamma} (M1), IL-4 (M2a), or IL-10 (M2c), followed by PTX intervention. Hemodynamic parameters (mPAP) and right ventricular hypertrophy index (RVHI) were measured. Pathological changes were assessed via HE staining. Single-cell RNA sequencing analyzed macrophage subsets in lung tissues. Macrophage polarization and NF-{kappa}B pathway activity were evaluated using immunohistochemistry, qPCR, cytokine profiling and Western blot. ResultsIn a severe PAH model induced by left pneumonectomy plus monocrotaline, pulmonary interstitial macrophages initially exhibited a predominant M1-polarized phenotype in the early stage, which transitioned to an M2a-polarized phenotype in the later stage and eventually stabilized. Low-dose PTX alleviated severe PAH by reducing perivascular macrophage infiltration. Cytological studies confirmed that PTX inhibited M2a polarization via suppression of NF-{kappa}B, thereby attenuating its proliferative effects on pulmonary arterial smooth muscle cells (PASMCs). ConclusionM2a macrophages play a crucial role in PAH progression. PTX may alleviate PAH by suppressing M2a polarization via the NF-{kappa}B pathway.

immunology↗

bioRxiv2025

Benchmarking RNA velocity methods across 17 independent studies

RNA velocity techniques offer great potential for unveiling trajectories of cell state transitions in different biological contexts. While diverse computational methods have been developed, there is no evidence-based guidelines for best-practice in RNA velocity inference. Here we conducted a benchmark study for 14 existing RNA velocity methods in 17 independent datasets. Many validations were done for the first time. We evaluated the performances of each method by measuring accuracy, stability, and usability. Our data showed no single method exhibited superior performance in all the assessments, and unexpected underperformance was observed in certain cases. Especially, the lack of uniformity in the inference results highlights the necessity to compare and control of multiple methods in a single analysis. Our study revealed current limitations and challenges in the RNA velocity methods and informed the best-practice for future studies.

bioinformatics↗

bioRxiv2025

RNA reinforces condensate nucleation on chromatin to amplify oncogenic transcription

Aberrant chromatin-associated condensates have emerged as drivers of transcriptional dysregulation in cancer. Although extensive studies have elucidated intrinsic protein sequence features governing their formation, how extrinsic factors within the chromatin environment modulate their assembly and pathogenic function remains poorly understood. Gain-of-function mutations in the histone acetylation reader ENL, found in pediatric leukemia and Wilms tumor, drive oncogenesis by inducing condensate formation at highly selective genomic loci. Here, we uncover a critical role for locally produced gene transcripts in reinforcing the nucleation, chromatin engagement, and oncogenic activity of ENL mutant condensates. Mutant ENL binds RNA in part through a conserved basic patch within its YEATS domain, and this interaction enhances condensate formation both in vitro and across diverse cellular contexts. Using a chemically inducible condensate displacement and re-nucleation system, we show that blocking ENL-RNA interactions or transcription impairs condensate reformation at endogenous targets. RNA interactions preferentially enhance mutant ENL occupancy at top-bound, condensate-permissive loci, leading to increased transcriptional bursting and robust gene activation at the single-cell and single-allele level. In mouse models, disrupting ENL-RNA interactions reduces condensate formation and oncogenic transcription in hematopoietic stem and progenitor cells, thereby suppressing ENL mutant-driven leukemogenesis. Together, these findings demonstrate that locally produced RNA transcripts can promote locus-specific nucleation of pathogenic condensates on chromatin, which in turn drive persistent and hyperactive transcription of oncogenic targets and lead to tumorigenesis.

molecular biology↗

bioRxiv2025

Ultra-performance liquid chromatography-mass spectrometry analysis of post-mortem brain tissue reveals specific amino acid profile dysregulation in Parkinson's Disease and Alzheimer's Disease patients

BackgroundCombined metabolomic and HPLC-based analyses have identified significant metabolic alterations in serum and plasma amino acid levels of Parkinsons disease (PD) patients, underscoring their potential as biomarkers. However, it remains unclear whether these biochemical changes also manifest within the central nervous system or are confined to peripheral metabolism, reflecting systemic metabolic disturbances. MethodsTo address this issue, here we measured the levels of 44 different amino acids in post-mortem brain samples from MPTP-intoxicated, L-DOPA-treated monkeys and PD patients at different Braak Lewy body (LB) stages, compared to their respective controls, through targeted Ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). ResultsIn MPTP-intoxicated monkeys, UPLC-MS revealed significant elevations in GABA, citrulline, threonine, isoleucine, phenylalanine, valine, glycine, and serine in the putamen, whereas we failed to detect alterations in the superior frontal gyrus (SFG). In PD patients, caudate-putamen (CPu) analysis demonstrated consistent serine upregulation across Braak LB stages 3-4 and 6, with stage 6 specifically showing additional proline increases and phosphoethanolamine decreases. Notably, serine was the sole amino acid significantly altered in both the putamen of MPTP-intoxicated monkeys and the CPu of PD patients. No significant amino acid alterations were observed in the SFG of PD patients, mirroring the findings in monkeys. In contrast, Alzheimers disease (AD) patient SFG samples showed significant increases in tryptophan, phenylalanine, threonine, tyrosine, and methionine relative to controls. ConclusionsThese findings demonstrate that cerebral amino acid alterations in PD are region-specific and primarily localized to brain areas receiving nigrostriatal dopaminergic innervation. Moreover, the cortical amino acid profile in AD differs substantially from that in PD, suggesting disease-specific metabolic signatures in distinct neurodegenerative conditions.

neuroscience↗