Role of exercise in modulating prefrontal cortical activation for improved gait and cognition in Parkinson's disease patients.

PURPOSE: This narrative review evaluated the impact of exercise on gait and cognitive functions in patients with Parkinson's disease (PD), focusing on prefrontal cortical (PFC) activation assessed using near-infrared spectroscopy (NIRS). METHODS: A literature search was conducted in the PubMed and Web of Science databases using keywords such as "Parkinson's disease," "gait," "cognitive functions," "exercise," and "NIRS," focusing on publications from the last decade. Studies measuring PFC activity using NIRS during gait tasks in patients with PD were selected. RESULTS: The review indicated that patients with PD demonstrate increased PFC activity during gait tasks compared to healthy controls, suggesting a greater cognitive demand for movement control. Exercise has been shown to enhance neural efficiency, thus improving gait and cognitive functions. CONCLUSION: Exercise is crucial for improving gait and cognitive functions in patients with PD through increased PFC activation. This emphasizes the importance of incorporating exercise into PD management plans and highlights the need for further studies on its long-term effects and the neurobiological mechanisms underlying its benefits, with the aim of optimizing therapeutic strategies and improving patients' quality of life.

Clinical usefulness of the SARC-F questionnaire to assess sarcopenia in patients with Parkinson's disease.

OBJECTIVE: To investigate the accuracy of the SARC-F questionnaire to identify sarcopenia in patients with Parkinson's disease (PD). METHODS: We prospectively recruited patients with PD who had a score of 3 or lower on the Hoehn and Yahr (H&Y) scale. Appendicular skeletal muscle mass (ASM), hand grip strength, and the SARC-F were used to assess sarcopenia. The cutoffs for the ASM index and hand grip strength to diagnose sarcopenia were based on the Asian Working Group for Sarcopenia 2019 consensus. A score ≥4 on the SARC-F was considered at risk for sarcopenia. RESULTS: A total of 365 patients with PD were included (mean age, 71.1 years; men, 53.2 %), and 73 (20.0 %) were diagnosed with sarcopenia. The area under the receiver operating characteristic curve of the SARC-F was 0.702 (95 % confidence interval, 0.634-0.770). Using the recommended cutoff score of ≥4, the SARC-F showed a sensitivity of 38.4 %, specificity of 85.6 %, positive predictive value (PPV) of 40.0 %, and negative predictive value (NPV) of 84.7 %. The Youden's index was the highest at a cutoff score of ≥2, in which the SARC-F showed a sensitivity of 67.1 %, specificity of 65.4 %, PPV of 32.7 %, and NPV of 88.8 %. These predictive values were similar to those obtained using a cutoff score of ≥2.5 or 3 on the H&Y scale. CONCLUSION: The application of the SARC-F to the mild-to moderate PD population is not appropriate as a first-step screening tool to diagnose sarcopenia. Given the comparable predictive values of the SARC-F and H&Y scale, this questionnaire may be considered only for ruling out sarcopenia in patients with similar disease severity.

Stem cell factor and cKIT modulate endothelial glycolysis in hypoxia.

AIMS: In hypoxia, endothelial cells (ECs) proliferate, migrate, and form new vasculature in a process called angiogenesis. Recent studies have suggested that ECs rely on glycolysis to meet metabolic needs for angiogenesis in ischaemic tissues, and several studies have investigated the molecular mechanisms integrating angiogenesis and endothelial metabolism. Here, we investigated the role of stem cell factor (SCF) and its receptor, cKIT, in regulating endothelial glycolysis during hypoxia-driven angiogenesis. METHODS AND RESULTS: SCF and cKIT signalling increased the glucose uptake, lactate production, and glycolysis in human ECs under hypoxia. Mechanistically, SCF and cKIT signalling enhanced the expression of genes encoding glucose transporter 1 (GLUT1) and glycolytic enzymes via Akt- and ERK1/2-dependent increased translation of hypoxia inducible factor 1A (HIF1A). In hypoxic conditions, reduction of glycolysis and HIF-1α expression using chemical inhibitors significantly reduced the SCF-induced in vitro angiogenesis in human ECs. Compared with normal mice, mice with oxygen-induced retinopathy (OIR), characterized by ischaemia-driven pathological retinal neovascularization, displayed increased levels of SCF, cKIT, HIF-1α, GLUT1, and glycolytic enzymes in the retina. Moreover, cKIT-positive neovessels in the retina of mice with OIR showed elevated expression of GLUT1 and glycolytic enzymes. Further, blocking SCF and cKIT signalling using anti-SCF neutralizing IgG and cKIT mutant mice significantly reduced the expression of HIF-1α, GLUT1, and glycolytic enzymes and decreased the pathological neovascularization in the retina of mice with OIR. CONCLUSION: We demonstrated that SCF and cKIT signalling regulate angiogenesis by controlling endothelial glycolysis in hypoxia and elucidated the SCF/cKIT/HIF-1α axis as a novel metabolic regulation pathway during hypoxia-driven pathological angiogenesis.

Clinical Utility of Whole-Genome Analysis as One-for-All Test for Breast Cancer: A Case Series.

Introduction: Breast cancer exhibits vast genomic diversity, leading to varied clinical manifestations. Integrating molecular subtyping with in-depth genomic profiling is pivotal for informed treatment choices and prognostic insights. Whole-genome clinical analysis provides a holistic view of genome-wide variations, capturing structural changes and affirming tumor suppressor gene loss of heterozygosity. Case Presentation: Here we detail four unique breast cancer cases from Seoul St. Mary's Hospital, highlighting the actionable benefits and clinical value of whole-genome sequencing (WGS). As an all-in-one test, WGS demonstrates significant clinical utility in these cases, including: (1) detecting homologous recombination deficiency with underlying somatic causal variants (case 1), (2) distinguishing double primary cancer from metastasis (case 2), (3) uncovering microsatellite instability (case 3), and (4) identifying rare germline pathogenic variants in TP53 gene (case 4). Our observations underscore the enhanced clinical relevance of WGS-based testing beyond pinpointing a few driver mutations in conventional targeted panel sequencing platforms. Conclusion: With genomic advancements and decreasing sequencing costs, WGS stands out as a transformative tool in oncology, paving the way for personalized treatment plans rooted in individual genetic blueprints.

Whole-genome sequences reveal zygotic composition in chimeric twins.

While most dizygotic twins have a dichorionic placenta, rare cases of dizygotic twins with a monochorionic placenta have been reported. The monochorionic placenta in dizygotic twins allows in utero exchange of embryonic cells, resulting in chimerism in the twins. In practice, this chimerism is incidentally identified in mixed ABO blood types or in the presence of cells with a discordant sex chromosome. Here, we applied whole-genome sequencing to one triplet and one twin family to precisely understand their zygotic compositions, using millions of genomic variants as barcodes of zygotic origins. Peripheral blood showed asymmetrical contributions from two sister zygotes, where one of the zygotes was the major clone in both twins. Single-cell RNA sequencing of peripheral blood tissues further showed differential contributions from the two sister zygotes across blood cell types. In contrast, buccal tissues were pure in genetic composition, suggesting that in utero cellular exchanges were confined to the blood tissues. Our study illustrates the cellular history of twinning during human development, which is critical for managing the health of chimeric individuals in the era of genomic medicine.

Mitochondrial DNA mosaicism in normal human somatic cells.

Somatic cells accumulate genomic alterations with age; however, our understanding of mitochondrial DNA (mtDNA) mosaicism remains limited. Here we investigated the genomes of 2,096 clones derived from three cell types across 31 donors, identifying 6,451 mtDNA variants with heteroplasmy levels of ≳0.3%. While the majority of these variants were unique to individual clones, suggesting stochastic acquisition with age, 409 variants (6%) were shared across multiple embryonic lineages, indicating their origin from heteroplasmy in fertilized eggs. The mutational spectrum exhibited replication-strand bias, implicating mtDNA replication as a major mutational process. We evaluated the mtDNA mutation rate (5.0 × 10-8 per base pair) and a turnover frequency of 10-20 per year, which are fundamental components shaping the landscape of mtDNA mosaicism over a lifetime. The expansion of mtDNA-truncating mutations toward homoplasmy was substantially suppressed. Our findings provide comprehensive insights into the origins, dynamics and functional consequences of mtDNA mosaicism in human somatic cells.

Quantitative and qualitative mutational impact of ionizing radiation on normal cells.

The comprehensive genomic impact of ionizing radiation (IR), a carcinogen, on healthy somatic cells remains unclear. Using large-scale whole-genome sequencing (WGS) of clones expanded from irradiated murine and human single cells, we revealed that IR induces a characteristic spectrum of short insertions or deletions (indels) and structural variations (SVs), including balanced inversions, translocations, composite SVs (deletion-insertion, deletion-inversion, and deletion-translocation composites), and complex genomic rearrangements (CGRs), including chromoplexy, chromothripsis, and SV by breakage-fusion-bridge cycles. Our findings suggest that 1 Gy IR exposure causes an average of 2.33 mutational events per Gb genome, comprising 2.15 indels, 0.17 SVs, and 0.01 CGRs, despite a high level of inter-cellular stochasticity. The mutational burden was dependent on total irradiation dose, regardless of dose rate or cell type. The findings were further validated in IR-induced secondary cancers and single cells without clonalization. Overall, our study highlights a comprehensive and clear picture of IR effects on normal mammalian genomes.

Clinical application of whole-genome sequencing of solid tumors for precision oncology.

Genomic alterations in tumors play a pivotal role in determining their clinical trajectory and responsiveness to treatment. Targeted panel sequencing (TPS) has served as a key clinical tool over the past decade, but advancements in sequencing costs and bioinformatics have now made whole-genome sequencing (WGS) a feasible single-assay approach for almost all cancer genomes in clinical settings. This paper reports on the findings of a prospective, single-center study exploring the real-world clinical utility of WGS (tumor and matched normal tissues) and has two primary objectives: (1) assessing actionability for therapeutic options and (2) providing clarity for clinical questions. Of the 120 patients with various solid cancers who were enrolled, 95 (79%) successfully received genomic reports within a median of 11 working days from sampling to reporting. Analysis of these 95 WGS reports revealed that 72% (68/95) yielded clinically relevant insights, with 69% (55/79) pertaining to therapeutic actionability and 81% (13/16) pertaining to clinical clarity. These benefits include the selection of informed therapeutics and/or active clinical trials based on the identification of driver mutations, tumor mutational burden (TMB) and mutational signatures, pathogenic germline variants that warrant genetic counseling, and information helpful for inferring cancer origin. Our findings highlight the potential of WGS as a comprehensive tool in precision oncology and suggests that it should be integrated into routine clinical practice to provide a complete image of the genomic landscape to enable tailored cancer management.