Toxicological Function of Adipose Tissue: Focus on Persistent Organic Pollutants

Abstract

Background: Adipose tissue (AT) is involved in several physiological functions, including metabolic regulation, energy storage, and endocrine functions.Objectives: In this review we examined the evidence that an additional function of AT is to modulate persistent organic pollutant (POP) toxicity through several mechanisms.Methods: We reviewed the literature on the interaction of AT with POPs to provide a comprehensive model for this additional function of AT.Discussion: As a storage compartment for lipophilic POPs, AT plays a critical role in the toxicokinetics of a variety of drugs and pollutants, in particular, POPs. By sequestering POPs, AT can protect other organs and tissues from POPs overload. However, this protective function could prove to be a threat in the long run. The accumulation of lipophilic POPs will increase total body burden. These accumulated POPs are slowly released into the bloodstream, and more so during weight loss. Thus, AT constitutes a continual source of internal exposure to POPs. In addition to its buffering function, AT is also a target of POPs and may mediate part of their metabolic effects. This is particularly relevant because many POPs induce obesogenic effects that may lead to quantitative and qualitative alterations of AT. Some POPs also induce a proinflammatory state in AT, which may lead to detrimental metabolic effects.Conclusion: AT appears to play diverse functions both as a modulator and as a target of POPs toxicity.

Body Fats Accumulate Metabolic Products: Physical and Chemical Analysis in Vitro

“…Dense AP contain the largest number of C, H, and O, metals, such as Na and Ca, and chemical compounds containing hydroxide and carboxide groups. This could be due to the deposition property of lipids at chronic metabolic intoxication [23].…”

Immune system - drug metabolism interactions: Toxicological insight

“…the link between obesity, immuiny and in ammation is well documented (60,61). Likewise, various CYPs were found to be expressed in the adipose tissue which appears to be a "postliver" major organ involved in the activity of xenobiotic/drug metabolizing enzymes (62)(63)(64). Impaired immune response in animals and humans a ected by obesity, leading to increased risks of infection.…”

Persistent Organic Pollutants (POPs): A Primer for Practicing Clinicians

“…However, in the long term, this accumulation can lead to larger body burdens, which are then slowly released into the blood stream. When there is large mobilization of adipose tissue, such as during periods of weight loss, pregnancy, after pregnancy and during breastfeeding, the POPs may be released at a faster rate from adipose tissue into the blood stream [29]. Several studies have shown that after large weight losses, like after bariatric surgery, there are higher serum levels of POPs [30•, 31].…”

“…POPs may induce obesogenic effects and also induce a pro-inflammatory state that can lead to the metabolic syndrome and diabetes [29,32,33]. These effects may also be age/period of development specific [34].…”