Biology subjects

Kashiwagi, A.

Publications and source records attributed to Kashiwagi, A..

4 recordsLinked to original sources

bioRxiv2024

AMH protects the ovary from doxorubicin by regulating cell fate and the response to DNA damage

Anti-Mullerian hormone (AMH) protects the ovarian reserve from chemotherapy, and this effect is most pronounced with Doxorubicin (DOX). However, the mechanisms of DOX toxicity and AMH rescue in the ovary remain unclear. Herein, we characterize these mechanisms in various ovarian cell types using scRNAseq. In the mesenchyme, DOX activates the intrinsic apoptotic signaling pathway through p53 class mediators, particularly affecting theca progenitors, while co-treament with AMH halts theca differentiation and reduces apoptotic gene expression. In preantral granulosa cells, DOX upregulates the cell cycle inhibitor Cdkn1a and dysregulates Wnt signaling, which are ameliorated by AMH co-treatment. Finally, in follicles, AMH induces Id3, a protein involved in DNA repair, which is necessary to prevent the accumulation of DNA lesions marked by {gamma}-H2AX in granulosa cells. Altogether this study characterizes cell, and follicle stage-specific mechanisms of AMH protection of the ovary, offering promising new avenues for fertility preservation in cancer patients undergoing chemotherapy. HighlightsO_LIDoxorubicin treatment induces DNA damage that activates the p53 pathway in stromal and follicular cells of the ovary. C_LIO_LIAMH inhibits the proliferation and differentiation of theca and granulosa cells and promotes follicle survival following Doxorubicin insult. C_LIO_LIAMH treatment mitigates Doxorubicin-induced DNA damage in the ovary by preventing the accumulation of {gamma}-H2AX-positive unresolved foci, through increased expression of ID3, a protein involved in DNA repair. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=189 SRC="FIGDIR/small/595356v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@19f6752org.highwire.dtl.DTLVardef@383e74org.highwire.dtl.DTLVardef@8c38f7org.highwire.dtl.DTLVardef@1efe797_HPS_FORMAT_FIGEXP M_FIG C_FIG

developmental biology↗

bioRxiv2023

Revealing Gene Expression Heterogeneity in a Clonal Population of Tetrahymena thermophila through Single-Cell RNA Sequencing

We performed single-cell RNA sequencing (scRNA-seq) on a population of 5,000 Tetrahymena thermophila, using the 10x Genomics 3 gene expression analysis, to investigate gene expression variability within this clonal population. Initially, we estimated the 3-untranslated regions (3 UTRs), which were absent in existing annotation files but are crucial for the 10x Genomics 3 gene expression analysis, using the peaks2utr method. This allowed us to create a modified annotation file, which was then utilized in our scRNA-seq analysis. Our analysis revealed significant gene expression variability within the population, even after removing the effect of cell phase-related features. This variability predominantly appeared in six distinct clusters. Through gene ontology and KEGG pathway enrichment analyses, we identified that these were primarily associated with ribosomal proteins, proteins specific to mitochondria, proteins involved in peroxisome-specific carbon metabolism, cytoskeletal proteins, motor proteins, and immobilized antigens.

microbiology↗

bioRxiv2022

A single cell atlas of the cycling murine ovary

The estrous cycle is regulated by rhythmic endocrine interactions of the nervous and reproductive systems, which coordinate the hormonal and ovulatory functions of the ovary. Folliculogenesis and follicle progression require the orchestrated response of a variety of cell types to allow the maturation of the follicle and its sequela, ovulation, corpus luteum (CL) formation, and ovulatory wound repair. Little is known about the cell state dynamics of the ovary during the estrous cycle, and the paracrine factors that help coordinate this process. Herein we used single-cell RNA sequencing to evaluate the transcriptome of > 34,000 cells of the adult mouse ovary and describe the transcriptional changes that occur across the normal estrous cycle and other reproductive states to build a comprehensive dynamic atlas of murine ovarian cell types and states.

developmental biology↗

bioRxiv2020

Microtubule Defect Involved in 'Mitophagy Resistance' Under Subacute Oxidative Stress - Potential Mechanism for Cellular Inflammation

IntroductionOxidative stress is considered an essential mechanism in ICU-acquired weakness. The roles of oxidative stress in autophagy/mitophagy dysfunction remains elusive. Microtubule serves as an essential guide rail for auto/mitophagosome trafficking required for proper maturation of auto/mitophagosomes in normal circumstances, and microtubules network formation is regulated by signal transduction mechanisms involving Akt, GSK3{beta}, and the microtubule plus-end tracking molecule, EB1. We have investigated (1) whether oxidative stress affects this pathway, leading to the defective mitophagy response, and (2) whether trehalose, an auto/mitophagy modulator, can ameliorate these pathological conditions. MethodsBy stably transfecting markers for auto/mitophagy or MT synthesis, we have established a few new C2C12 myocyte cell lines, expressing, GFP-LC3, EB1-GFP, and/or tandem-fluorescence LC3 (tfLC3). To monitor microtubule network, the cells were stained by SiR-tubulin. The cells were cultured in the presence or absence of oxidative stress by hydrogen peroxide (H2O2) and treated with or without trehalose. The response of mitophagy parameters including vesicle motion and the maturation status was monitored by stimulating the cells with carbonyl cyanide m-chlorophenyl hydrazone (CCCP), an established mitophagy inducer, under a time-lapse confocal microscopy. Signal transduction mechanisms linking mitophagy to microtubule formation was analyzed by Western Blotting against Akt and GSK3{beta}. ResultsCells under the oxidative stress, showed abolished MT network formation, decreased microtubule synthesis by EB1, and a decrease in CCCP-invoked response of mitophagosome motion, perturbed mitophagosome maturation, and increased superoxide production. Signal resistance of Akt/GSK3{beta} pathway to mitophagic stimulation, was documented. Trehalose treatment reversed signal resistance, diminished MT synthesis, ameliorated the disturbed MT network, and improved maturation defects, suppressing the production of superoxide. ConclusionsOxidative stress decreases the response of mitophagy and abolishes microtubule network. Trehalose improves the synthetic ability of microtubule and normalized the disturbed microtubule network, resulting in the improvement of the perturbed mitophagosomes maturation under the oxidative stress.

cell biology↗