The prevalence of obesity is growing at an alarming rate worldwide, and current therapies have limited benefits. Therefore, it is essential to increase our understanding of the underlying mechanisms so that new strategies can be developed to reduce the incidence of obesity related diseases. Adiponectin is an adipocyte-derived hormone that regulates glucose and lipid metabolism via direct and indirect mechanisms and has anti-inflammatory, anti-diabetic, anti-atherogenic and cardioprotective properties. Hypoadiponectinemia is implicated in the aetiology of obesity-related diseases making strategies to increase circulating adiponectin levels therapeutically attractive.Emerging evidence, predominantly from preclinical studies, suggests induction of heme-oxygenase-1 (HO-1) increases adiponectin production concomitant with decreased inflammatory tone prompting the proposal of a "HO-1 -adiponectin axis." However, the underlying mechanisms of increased adiponectin production via HO-1 induction are poorly defined; indeed a direct relationship has not been demonstrated. Thus, the overarching aim of this thesis is to investigate the effects of HO-1 induction on adiponectin production as well as adipocyte and adipose tissue remodelling and metabolic parameters using cellular and mouse models.Initial studies were designed to characterize the direct effect of HO-1 induction on adiponectin production. We found that treatment with the widely used HO-1 inducer cobalt protoporphyrin (CoPP) or hemin for 24-48 h increased HO-1 expression and activity without affecting adiponectin expression and secretion, in human mature adipocyte under a variety of experimental scenarios.Treatment of adipocytes with TNFα reduced adiponectin production and induced pro-inflammatory cytokines production. HO-1 induction failed to reverse these effects. These results do not support a direct HO-1 -adiponectin axis.However, literature suggests that chronic induction of HO-1 via CoPP administration throughout differentiation, promotes adiponectin secretion, albeit in the context of reduced adipogenesis. While our previous findings argued against the existence of a direct "HO-1 -adiponectin axis," they did not address the potential effects of chronic induction of HO-1 on adiponectin production. Thus, we extended our study to characterise the effects of chronic HO-1 induction throughout differentiation of human preadipocytes. In this study we demonstrate that chronic induction of HO-1 with CoPP or hemin throughout differentiation results in dose-dependent inhibition of adipogenesis and adiponectin production as well as induction of additional NRF2 target genes. Co-treatment with SnMP (HO-1 activity inhibitor) and HO-1 siRNA did not prevent these effects. These findings suggest that the chronic treatment with CoPP or hemin inhibits adipogenesis and adiponectin production potentially by a HO-1-independent mechanism that may be downstream of NRF2.iii However, our results contradict the majority of reports in the literature. One possibility is that the ...