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Yasoda, A.

Publications and source records attributed to Yasoda, A..

3 recordsLinked to original sources

Transcriptomic Landscape of Hyperthyroidism in Mice Overexpressing Thyroid Stimulating Hormone

Hyperthyroidism is a condition with excessive thyroid hormone secretion. Activation of thyroid stimulating hormone receptor (TSHR) fundamentally leads to hyperthyroidism. The details of TSHR signaling remain to be elucidated. We conducted transcriptome analyses for hyperthyroid mice that we generated by overexpressing TSH. TSH overexpression via hydrodynamic gene delivery with pLIVE-TSHB and pLIVE-CGA vectors consistently caused hyperthyroidism and goiters for at least 4 weeks in C57BL/6J mice. RNA sequencing analysis of their thyroid glands revealed that thiamazole slightly changed the thyroid transcriptome, which reinforces a conventional theory that thiamazole decreases thyroid hormone secretion via inhibition of thyroid peroxidase activity. Meanwhile, TSH overexpression drastically changed the thyroid transcriptome. In particular, enrichment analyses identified the cell cycle, phosphatidylinositol-3 kinase/Akt pathway, and Ras-related protein 1 pathway as possibly associated with goiter development. Regarding the role of TSHR signaling in hyperthyroidism, it is noteworthy that Slc26a4 was exclusively upregulated among genes crucial to thyroid hormone secretion at both 1 and 4 weeks after hydrodynamic gene delivery. To verify the relationship between this upregulation and hyperthyroidism, we overexpressed TSH in Slc26a4 knockout mice. TSH overexpression caused hyperthyroidism in Slc26a4 knockout mice, equivalent to that in control mice. To summarize, we analyzed hyperthyroid mice generated by TSH overexpression. We did not observe significant changes in known genes and pathways involved in thyroid hormone secretion. Thus, our datasets might include candidate genes that have not yet been identified as regulators of thyroid function. Our transcriptome datasets regarding hyperthyroidism can contribute to future research on TSHR signaling.

physiology↗

Novel Thyroid-Specific Autoantibodies in Patients with Immune-Related Adverse Events Involving the Thyroid Gland

AimsProgrammed cell death-1 (PD-1) blockade therapy frequently results in immune-related adverse events involving the thyroid gland (thyroid irAEs). Although clinical features of thyroid irAEs are known, the mechanisms remain unclear. Here, we conducted a pilot study to investigate mechanisms of thyroid irAE development from the perspective of autoantibodies. MethodsWe performed immunoprecipitation-based assays using sera of 3 patients who developed thyroid irAEs with PD-1 blockade therapy by nivolumab and HEK293T cell lysates, including overexpressed proteins of interest (NKX2-1, PAX8, FOXE1, and HHEX; thyroid-specific transcriptional factors). The pellets were analyzed by western blot to detect the HiBit tag attached to the C-terminus of the proteins. ResultsRelevant changes to NKX2-1 bands were not seen in all 3 patients, but PAX8 bands were augmented in patient 2 with lung cancer and patient 3 with renal cell carcinoma. In addition, FOXE1 bands were augmented in patient 1 with malignant melanoma and patient 3, and a HHEX band was augmented in patient 3. Thus, we revealed novel thyroid-specific autoantibodies, PAX8Ab, FOXE1Ab, and HHEXAb. Expression patterns of the antigens recognized by these antibodies were not identical to the primary sites, so autoimmune responses in thyroid irAE may originate from the thyroid gland, and not the malignancy. Considering that TPOAb rather than TgAb is often negative in patients with thyroid irAEs, other mechanisms such as cytotoxic T cell and antigenicity of thyroglobulin may be involved. ConclusionsAlthough the significance of these novel autoantibodies needs further examination, the present study provides new insights for thyroid autoimmunity.

immunology↗

Periosteum-derived Osteocrin regulates bone growth through both endochondral ossification and intramembranous ossification

During development of long bones, two mechanistically distinct processes contribute to long- and short-axis growth. Endochondral ossification in the growth plate leads to the long-axis growth, while intramembranous ossification including apposition in the periosteum regulates the short axis growth. Here, we show that periosteal osteoblast-derived secretory peptide, Osteocrin (OSTN), promotes both types of long bone growth through potentiation of signaling by C-type natriuretic peptide (CNP), because OSTN inhibits the clearance of CNP by binding to natriuretic peptide receptor 3 (NPR3). The mice lacking OSTN showed less bone mass in trabecular and cortical regions than the control mice, suggesting the dual functions of OSTN in long bone growth. We found that OSTN regulated trabecular bone formation by inducing proliferation and maturation of chondrocytes possibly through enhancing CNP-dependent signaling. Besides the contribution of OSTN to long axis growth, we demonstrated that OSTN together with CNP induced osteoblast differentiation of periosteum-derived multipotent progenitor cells expressing NPR3. These data suggest that OSTN induces long bone growth through endochondral ossification and osteoblast specification of multipotent progenitor cells in the periosteum.

developmental biology↗