👤 Kensuke Shiomi

Agricultural or gardening activity (also known as hobby farming) is a simple strategy that may be effective for maintaining health and preventing lifestyle-related diseases. However, its preventive effect on the development of conditions associated with neurovascular aging (e.g., stroke and dementia) remains unclear. To comprehensively investigate the preventive role of regular agricultural or gardening physical activity (AGPA) in neurovascular aging and its underlying mechanisms using two approaches. We conducted an experimental study in which we assessed arterial stiffness, cognitive performance (Flanker and Stroop tests), and circulating biomarkers (e.g., plasmin-α2-plasmin inhibitor complexes, nitric oxide, brain-derived neurotrophic factor) in 12 male students (average age: 22 ± 1 years) before and after three 40-min interventions (resting, cycling, and simulated AGPA) under controlled conditions. We also conducted a cross-sectional study, in which we recruited 161 (79 in the AGPA group and 82 in the control group) hospital-based older individuals (average age: 78 ± 5 years) and assessed their history of stroke, cognitive function, and brain magnetic resonance imaging (MRI) findings. In the experimental study, simulated AGPA reduced arterial stiffness, improved executive cognitive function, and elevated circulating plasmin-α2-plasmin inhibitor complexes, nitric oxide, and brain-derived neurotrophic factor. Brain MRI-assessed cerebral white matter hyperintensities caused by reduced blood flow to brain tissue and stroke prevalence were lower, and cognitive scores (as assessed by the Hasegawa Dementia Scale-Revised) were higher in the AGPA group than in the control group. Our findings suggest that regular AGPA is associated with markers of slower neurovascular aging in older individuals. AGPA induces a combination of general physical activity-related and specific AGPA-related effects; moreover, it may offer similar or even greater benefits than physical activity alone. Therefore, habitual AGPA may serve as an effective preventive strategy for neurovascular aging. Show less

IgM-related AL amyloidosis is a rare and distinct clinical entity, often associated with underlying lymphoproliferative disorders such as Waldenström's macroglobulinemia (WM) or lymphoplasmacytic lymphoma (LPL). Unlike non-IgM AL amyloidosis, it exhibits unique organ involvement patterns and generally poorer prognosis. We report a 66-year-old woman diagnosed with WM complicated by systemic IgM-κ AL amyloidosis. She received combination chemotherapy with rituximab and bendamustine (BR), resulting in a reduction of serum IgM levels. Despite the hematologic improvement, her liver dysfunction rapidly progressed, and she died of hepatic failure just two months after diagnosis. Pathological autopsy revealed massive IgM-κ amyloid deposition in the liver and multiple organs, with no residual lymphoma in the bone marrow or lymph nodes. These findings suggest that extensive hepatic amyloid infiltration was already present at diagnosis, and that organ response could not be achieved despite hematologic improvement. This case highlights the aggressive nature of IgM-related AL amyloidosis and the critical importance of early detection, especially when liver dysfunction is observed. Current therapies targeting the underlying clone may not be sufficient in cases with advanced organ involvement, emphasizing the urgent need for novel strategies to facilitate amyloid clearance and protect organ function. Show less

Mutually exclusive KIT and PDGFRA mutations are considered to be the earliest events in gastrointestinal stromal tumors (GIST), but insufficient for their malignant progression. Herein, we aimed to identify driver genes and signaling pathways relevant to GIST progression. We investigated genetic profiles of 707 driver genes, including mutations, gene fusions, copy number gain or loss, and gene expression for 65 clinical specimens of surgically dissected GIST, consisting of six metastatic tumors and 59 primary tumors from stomach, small intestine, rectum, and esophagus. Genetic alterations included oncogenic mutations and amplification-dependent expression enhancement for oncogenes (OG), and loss of heterozygosity (LOH) and expression reduction for tumor suppressor genes (TSG). We assigned activated OG and inactivated TSG to 27 signaling pathways, the activation of which was compared between malignant GIST (metastasis and high-risk GIST) and less malignant GIST (low- and very low-risk GIST). Integrative molecular profiling indicated that a greater incidence of genetic alterations of driver genes was detected in malignant GIST (96%, 22 of 23) than in less malignant GIST (73%, 24 of 33). Malignant GIST samples groups showed mutations, LOH, and aberrant expression dominantly in driver genes associated with signaling pathways of PI3K (PIK3CA, AKT1, and PTEN) and the cell cycle (RB1, CDK4, and CDKN1B). Additionally, we identified potential PI3K-related genes, the expression of which was upregulated (SNAI1 and TPX2) or downregulated (BANK1) in malignant GIST. Based on our observations, we propose that inhibition of PI3K pathway signals might potentially be an effective therapeutic strategy against malignant progression of GIST. Show less

Wnt signaling plays a crucial role in directing cell differentiation, polarity, and growth. In the canonical pathway, Wnt receptors activate Dishevelled (Dvl), which then blocks the degradation of a key signal transducer, beta-catenin, leading to the nuclear accumulation of beta-catenin and induction of Wnt target genes through TCF/LEF family transcription factors. Here we identified a novel zebrafish gene encoding Ccd1, which possesses a DIX (Dishevelled-Axin) domain. DIX domains are essential for the signal transduction of two major Wnt downstream mediators, Dvl and Axin. Ccd1 formed homomeric and heteromeric complexes with Dvl and Axin and activated TCF-dependent transcription in vitro. In addition, overexpression of ccd1 in zebrafish embryos led to a reduction in the size of the eyes and forebrain (posteriorization), as seen with wnt8 overexpression, whereas a dominant-negative ccd1 (DN-ccd1) caused the opposite phenotype. Furthermore, the Wnt activation phenotype induced by ccd1 was inhibited by the expression of axin1 or DN-ccd1, and the wnt8 overexpression phenotype was rescued by DN-ccd1, suggesting that Ccd1 functions downstream of the Wnt receptor and upstream of Axin. These results indicate that Ccd1 is a novel positive regulator in this Wnt signaling pathway during zebrafish neural patterning. Show less