Advertisement
Research Article

Metabolic Consequences and Vulnerability to Diet-Induced Obesity in Male Mice under Chronic Social Stress

  • Alessandro Bartolomucci mail,

    alessandro.bartolomucci@unipr.it

    Affiliation: Department of Evolutionary and Functional Biology, University of Parma, Parma, Italy

    X
  • Aderville Cabassi,

    Affiliation: Department of Internal Medicine, Nephrology and Health Sciences, University of Parma, Parma, Italy

    X
  • Paolo Govoni,

    Affiliation: Department of Experimental Medicine, University of Parma, Parma, Italy

    X
  • Graziano Ceresini,

    Affiliation: Department of Internal Medicine and Biomedical Sciences, University of Parma, Parma, Italy

    X
  • Cheryl Cero,

    Affiliation: Department of Evolutionary and Functional Biology, University of Parma, Parma, Italy

    X
  • Daniela Berra,

    Affiliation: Department of Evolutionary and Functional Biology, University of Parma, Parma, Italy

    X
  • Harold Dadomo,

    Affiliation: Department of Evolutionary and Functional Biology, University of Parma, Parma, Italy

    X
  • Paolo Franceschini,

    Affiliation: Department of Evolutionary and Functional Biology, University of Parma, Parma, Italy

    X
  • Giacomo Dell'Omo,

    Affiliation: Ornis Italica, Rome, Italy

    X
  • Stefano Parmigiani equal contributor,

    equal contributor Contributed equally to this work with: Stefano Parmigiani, Paola Palanza

    Affiliation: Department of Evolutionary and Functional Biology, University of Parma, Parma, Italy

    X
  • Paola Palanza equal contributor

    equal contributor Contributed equally to this work with: Stefano Parmigiani, Paola Palanza

    Affiliation: Department of Evolutionary and Functional Biology, University of Parma, Parma, Italy

    X
  • Published: January 30, 2009
  • DOI: 10.1371/journal.pone.0004331
  • Published in PLOS ONE

Reader Comments (1)

Post a new comment on this article

Do human individualism/bonding fragilities play a role in obesity?

Posted by isabelaz on 31 Mar 2009 at 14:47 GMT

The findings of Alessandro Bartolomucci and collaborators (1) are really interesting and open a wide avenue of new hypothesis for the overwhelming obesity epidemic of our time. A lot of environmental changes of the last decades, repeatedly described, are logically and easily related to the increasing obesity prevalence. However, the dimensions of the phenomenon suggest that, beyond abundant energy dense food and sedentarism, less obvious factors are involved. Stress and disruption of circadian rhythmicity are being given attention. But the results of Bartolomucci et al with individually caged mice are absolutely new and inspiring: under normal chow diet these animals eat less and loose weight, but given access to a high fat diet they eat more and become obese, i.e., they exhibit an increased hedonic response (1).
We wonder if these individually caged mice could be a model of individualism, social isolation, and weak bonding societal conditions in present human societies. At least for children, and for the strange case of children obesity, this seems a forceful hypothesis, deserving consideration. Healthy children used to present a lack of interest in food, complaining when forced to abandon playing to attend the family meal. What is going on with these present day children that do not like to play outdoor games, and prefer instead being seated with palatable food at hand?
Will it be bonding problems, with mothers going back to work when their babies are only a few months old? With parents returning home late and too tired with no time for children? Perturbations of bonding create vulnerability to addiction behaviour (see 2). Another possibility is the putative effect of an egotistic attitude in children favoured by an indulging behaviour of parents that put no resistance to children wishes, don't teach them to respect and care for the other, and don't even allow them the oportunity to dream and/or aim at anything. Research work on these hypothesis could help to improve mental and physical health of next generations.

Laura Ribeiro, Diogo Pestana and Isabel Azevedo
Department of Biochemistry, Faculty of Medicine, University of Porto
4200-319 Porto, Portugal

References

1. Bartolomucci A, Cabassi A, Govoni P, et al (2009) Metabolic Consequences and Vulnerability to Diet-Induced Obesity in Male Mice under Chronic Social Stress. PLoS ONE. 4:e4331.

2. Henry JP (1997) Psychological and physiological responses to stress: The right hemisphere and the hypothalamo-pituitary-adrenal axis, an inquiry into problems of human bonding. Acta Physiol Scand 161, Suppl 640: 10-25.

No competing interests declared.

RE: Do human individualism/bonding fragilities play a role in obesity?

abartolomucci replied to isabelaz on 02 Apr 2009 at 07:24 GMT

Ribeiro, Pestana and Azevedo, highlighted the potential implications of one, somewhat unexpected, findings of our study (1), i.e. the hedonic response to high fat diet and the marked vulnerability to develop obesity of individually-housed male mice. This finding was unexpected considering the lower feeding and body weight loss under standard low fat diet (1), as well as the general phenotype of individually housed male mice (2-4). On the other hand, our findings are in agreement with a recent report in mice (belonging to stains different from the CD1 here used), which were vulnerable to high fat diet-induced obesity and type 2 diabetes (4).

The current stage of the research do not allow us proposing a direct parallel between our individually housed mouse model and the “isolated”, sedentary and overfed children. On the other hand we sincerely hope that the interesting translational view suggested by Ribeiro et al, would stimulate further interest in preclinical models aimed at understanding the relative contribution of environmental factors as well as the geneXenvironment interaction in determining obesity, as opposed to a pure candidate gene approach.
Findings in preclinical models would hopefully translate into a better understanding of the actual obesity pandemia in human being, and provide innovative research tools for prevention and treatment options.

Alessandro Bartolomucci, Stefano Parmigiani, Paola Palanza
Department of Evolutionary and Functional Biology, University of Parma, Italy


1. Bartolomucci A, Cabassi A, Govoni P, et al (2009) Metabolic Consequences and Vulnerability to Diet-Induced Obesity in Male Mice under Chronic Social Stress. PLoS ONE. 4:e4331.
2. Bartolomucci A, Palanza P, Sacerdote P, et al (2003) Individual housing induces altered immuno-endocrine responses to psychological stress in male mice. Psychoneuroendocrinology 28:540-58.
3. Valzelli L (1973) The "isolation syndrome" in mice. Psychopharmacologia 31:305-20.
4. Palanza P (2001). Animal models of anxiety and depression: how are females different? Neurosci Biobehav Rev 25:219-33.
5. Nonogaki K, Nozue K, Oka Y (2007) Social isolation affects the development of obesity and type 2 diabetes in mice. Endocrinology 148:4658-66.

No competing interests declared.