Discovering The Developmental Origins of Obesity

The Polish Academy of Sciences in Olsztyn, Poland


Praca dla studentów

Laboratorium Profesora Leslie P. Kozaka w Instytucie Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie poszukuje studentów ostatniego roku studiów magisterskich kierunków biologicznych do udziału w projekcie pt.: "Nutrition and ambient temperature during early development can reduce susceptibility to obesity". Wykonane badania będą jednocześnie przedmiotem obrony pracy magisterskiej.


Dr. Leslie Kozak was invited to present talks at:

  1. Technical University of Munich, The developmental origins of obesity, Munich, Germany, October, 2011.
  2. Gothenburg Medical University, UCP1-dependent and –independent thermogenesis and the regulation of body weight. Gothenburg, Sweden, March, 2012.
  3. BENZON SYMPOSIUM No. 58 Adipose Tissue in Health and Disease talk entitled, "The role of the early post-natal environment on the development of brown adipocytes in white fat depots" Copenhagen, August 27-30, 2012
  4. The Royal Society, London, UK Metabolism and Endocrinology Themed meeting, with symposium on "Brown adipose tissue: anew human organ?" talk entitled, "Does brown fat have a role in energy balance?" 11-13 December 2012.
  5. European Congress of Obesity, Enhancing energy expenditure during post-natal development with reduced ambient temperature. Liverpool, England, May 14, 2013.

Assessing the molecular basis for thermogenesis of brown adipocytes in interscapular brown fat and inguinal fat

tn Emilia Pawel poster Paris June 2013INTRODUCTION
Two types of fat tissue with diametrically opposing functions are present in humans and other mammals: white adipose tissue (WAT), which stores fat, and brown adipose tissue (BAT), which burns fat to produce heat. White adipocytes are almost completely filled with one lipid droplet surrounded by a thin layer of cytoplasm with little mitochondria. Brown adipocytes, in contrast, contain several small lipid droplets and a cytoplasm rich in mitochondria. BAT may exist in organism as a discrete organ that initially has been found in newborns mammals or it may exists as diffuse highly variable population of brown adipocytes within white fat depots (brite cells). While phenotypes of Ucp1-/- mice indicate that interscapular BAT (iBAT) is required for body temperature regulation, the function of brite cells is uncertain, although it is possible that induction and activation of brite cells may contribute to the regulation of body weight. Although the brown adipocytes of iBAT and brite cells have different genetic and developmental origins, it is unknown whether these two types of brown adipocytes have similar thermogenic capacities, that is, do these brown adipocytes have identical or different thermogenic potentiality. This property may be important to the effectiveness of each type of brown adipocyte in contributing to energy balance in an organism.


Inactivation of Sca-1 does not protect mice from diet-induced obesity

tn Barbara Kozak Keystone 2012 posterINTRODUCTION
Stem Cell Antigen-1 (Sca-1), a surface protein initially identified as an antigenic marker of murine hematopoietic cells, is commonly used for the identification of stem cells in various tissues. A substantial body of literature links stem cell antigen-1 (SCA-1) to stem cell function in adipose tissue.
In the present study we hypothesize that SCA-1 is a biomarker for adipocyte stem/progenitor cells within adipose tissue and that SCA-1 is required for adipose tissue expansion in an obesogenic environment.

Inherent Plasticity of Brown Adipogenesis in White Fat of Mice Allows for Recovery from Effects of Post-natal Malnutrition

tn Keystone Poster 2012INTRODUCTION
Interscapular brown adipose tissue (iBAT) is formed during fetal development and stable for the life span of the mouse. In addition, brown adipocytes also appear in white fat depots (wBAT) between 10 and 21 days of age in mice maintained at a room temperature of 23 °C. However, this expression is transient. By 60 days of age the brown adipocytes have disappeared, but they can re-emerge if the adult mouse is exposed to the cold (5°C) or treated with β3-adrenergic agonists.

Effects of rearing temperature and diet on susceptibility to adiposity in wild-type and UCP1-deficient mice

tn EMBO meeting poster ZuliaINTRODUCTION
Environmental conditions during early postnatal life exert long lasting effects by establishing a stable phenotype extending into adulthood. Alteration in developmental plasticity in response to environmental cues such as nutritional status or ambient temperature may lead to obesity in later life. Previous work demonstrated that UCP1-deficiency in adult mice is associated with resistance to diet-induced obesity (DIO) when the ambient temperature is below thermoneutral (28°C), by forcing an animal to activate alternative and less efficient thermogenic pathways (Liu et al., 2003; Anunciado-Koza et al., 2008). Others have found that UCP1-deficient mice are more susceptible to DIO when maintained at thermoneutrality (Feldmann et al., 2009).