Review article Men and mice: Relating their ages Sulagna Dutta a , Pallav Sengupta b, ⁎ a Ex-guest Teacher, Department of Physiology, Post-graduation Section, Serampore College, University of Calcutta, Kolkata, West Bengal, India b Department of Physiology, Vidyasagar College for Women, University of Calcutta, Kolkata, West Bengal, India abstract article info Article history: Received 20 July 2015 Received in revised form 19 October 2015 Accepted 22 October 2015 Available online xxxx Keywords: Age Developmental biology Human age Laboratory mice Mice age Physiology Since the late 18th century, the murine model has been widely used in biomedical research (about 59% of total animals used) as it is compact, cost-effective, and easily available, conserving almost 99% of human genes and physiologically resembling humans. Despite the similarities, mice have a diminutive lifespan compared to humans. In this study, we found that one human year is equivalent to nine mice days, although this is not the case when comparing the lifespan of mice versus humans taking the entire life at the same time without consid- ering each phase separately. Therefore, the precise correlation of age at every point in their lifespan must be de- termined. Determining the age relation between mice and humans is necessary for setting up experimental murine models more analogous in age to humans. Thus, more accuracy can be obtained in the research outcome for humans of a specific age group, although current outcomes are based on mice of an approximate age. To fill this gap between approximation and accuracy, this review article is the first to establish a precise relation be- tween mice age and human age, following our previous article, which explained the relation in ages of laboratory rats with humans in detail. © 2015 Elsevier Inc. All rights reserved. Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 2. Age determination of laboratory mice: common methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 2.1. Weight of eye lens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 2.2. Musculoskeletal examination: epiphyseal closure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 2.3. Body weight assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 2.4. TW pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 3. Relation between mice age and human age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 3.1. Relation between their lifespans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 3.2. Weaning period of mice and human . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 3.3. Mice and human age to attain puberty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 3.4. Age of adulthood onset in mice and its relation to human age of adulthood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 3.5. Reproductive senescence in mice and humans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 3.6. Post-senescence phase in mice and humans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 4. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 Conflict of interest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 Funding source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 1. Introduction Most studies in the field of life science (almost 59% of the experi- mental studies [1]) use experimental murine models (Mus musculus) for investigating the implications on human health and body (Fig. 1). In terms of their maximum lifespan, mice (4 years) and humans (120 Life Sciences xxx (2015) xxx–xxx ⁎ Corresponding author at: Department of Physiology, Vidyasagar College for Women, University of Calcutta, Kolkata, India. E-mail address: pallav_cu@yahoo.com (P. Sengupta). LFS-14535; No of Pages 5 http://dx.doi.org/10.1016/j.lfs.2015.10.025 0024-3205/© 2015 Elsevier Inc. All rights reserved. Contents lists available at ScienceDirect Life Sciences journal homepage: www.elsevier.com/locate/lifescie Please cite this article as: S. Dutta, P. Sengupta, Men and mice: Relating their ages, Life Sci (2015), http://dx.doi.org/10.1016/j.lfs.2015.10.025