Open AccessYoung transgenic hMTH1 mice are protected against dietary fat‐induced metabolic stress—implications for enhanced longevity
Author(s) -
Marcon Francesca,
Meschini Roberta,
Iorio Egidio,
Palleschi Simonetta,
Luca Gabriele,
Siniscalchi Ester,
Conti Luigi,
Chirico Mattea,
Pisanu Maria Elena,
Battistis Francesca,
Rossi Barbara,
Minoprio Anna,
Giuliani Alessandro,
Karran Peter,
Bignami Margherita
Publication year - 2022
Publication title -
aging cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.103
H-Index - 140
eISSN - 1474-9726
pISSN - 1474-9718
DOI - 10.1111/acel.13605
Subject(s) - oxidative stress , biology , dna damage , genome instability , senescence , endocrinology , medicine , microbiology and biotechnology , genetics , dna
Abstract hMTH1 protects against mutation during oxidative stress. It degrades 8‐oxodGTP to exclude potentially mutagenic oxidized guanine from DNA. hMTH1 expression is linked to ageing. Its downregulation in cultured cells accelerates RAS‐induced senescence, and its overexpression in hMTH1‐Tg mice extends lifespan. In this study, we analysed the effects of a brief (5 weeks) high‐fat diet challenge (HFD) in young (2 months old) and adult (7 months old) wild‐type (WT) and hMTH1‐Tg mice. We report that at 2 months, hMTH1 overexpression ameliorated HFD‐induced weight gain, changes in liver metabolism related to mitochondrial dysfunction and oxidative stress. It prevented DNA damage as quantified by a comet assay. At 7 months old, these HFD‐induced effects were less severe and hMTH1‐Tg and WT mice responded similarly. hMTH1 overexpression conferred lifelong protection against micronucleus induction, however. Since the canonical activity of hMTH1 is mutation prevention, we conclude that hMTH1 protects young mice against HFD by reducing genome instability during the early period of rapid growth and maximal gene expression. hMTH1 protection is redundant in the largely non‐growing, differentiated tissues of adult mice. In hMTH1‐Tg mice, expression of a less heavily mutated genome throughout life provides a plausible explanation for their extended longevity.