Possible Role of Activin in the Adiponectin Paradox-Induced Progress of Alzheimer’s Disease

Article type: Research Article

Authors: Hashimoto, Makoto^{a; *} | Ho, Gilbert^b | Sugama, Shuei^c | Takenouchi, Takato^d | Waragai, Masaaki^a | Sugino, Hiromu^a | Inoue, Satoshi^{e; f} | Masliah, Eliezer^g

Affiliations: [a] Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo, Japan | [b] PCND Neuroscience Research Institute, Poway, CA, USA | [c] Department of Physiology, Nippon Medical School, Tokyo, Japan | [d] Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan | [e] Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan | [f] Research Center for Genomic Medicine, Saitama Medical University, Saitama, Japan | [g] Division of Neuroscience, National Institute on Aging, Bethesda, MD, USA

Correspondence: [*] Correspondence to: Dr. Makoto Hashimoto, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan. Tel.: +1 81 3 6834 2354; Fax: +1 81 3 5316 3150; E-mail: [email protected].

Abstract: Accumulating evidence suggests that the adiponectin (APN) paradox might be involved in promoting aging-associated chronic diseases such as Alzheimer’s disease (AD). In human brain, APN regulation of the evolvability of amyloidogenic proteins (APs), including amyloid-β (Aβ) and tau, in developmental/reproductive stages, might be paradoxically manifest as APN stimulation of AD through antagonistic pleiotropy in aging. The unique mechanisms underlying APN activity remain unclear, a better understanding of which might provide clues for AD therapy. In this paper, we discuss the possible relevance of activin, a member of transforming growth factor β (TGFβ) superfamily of peptides, to antagonistic pleiotropy effects of APN. Notably, activin, a multiple regulator of cell proliferation and differentiation, as well as an endocrine modulator in reproduction and an organizer in early development, might promote aging-associated disorders, such as inflammation and cancer. Indeed, serum activin, but not serum TGFβ increases during aging. Also, activin/TGFβ signal through type II and type I receptors, both of which are transmembrane serine/threonine kinases, and the serine/threonine phosphorylation of APs, including Aβ 42 serine 8 and αS serine 129, may confer pathological significance in neurodegenerative diseases. Moreover, activin expression is induced by APN in monocytes and hepatocytes, suggesting that activin might be situated downstream of the APN paradox. Finally, a meta-analysis of genome-wide association studies demonstrated that two SNPs relevant to the activin/TGFβ receptor signaling pathways conferred risk for major aging-associated disease. Collectively, activin might be involved in the APN paradox of AD and could be a significant therapeutic target.

Keywords: Activin, adiponectin paradox, Alzheimer’s disease, amyloidogenic proteins, antagonistic pleiotropy, evolvability, transforming growth factor β

DOI: 10.3233/JAD-210206

Journal: Journal of Alzheimer's Disease, vol. Pre-press, no. Pre-press, pp. 1-8, 2021