Obesity has reached epidemic proportions in Western society and is
increasing in the developing world. It is considered one of the main contributors to the
global burden of disability and chronic diseases, including autoimmune, inflammatory
and degenerative diseases. It has notably transformed the obsolete concept that white
adipose tissue (WAT) serves simply as an energy deposit. WAT is now recognized as
an endocrine organ, active and inflammatory, capable of producing a wide variety of
factors known as adipokines. These molecules participate in a wide variety of
physiological and physiopathological processes, regulating food intake, insulin
sensitivity, immunity and inflammation. Obese patients have chronic inflammation due
to the sustained production of pro-inflammatory cytokines in adipose tissue and higher
levels of inflammatory cytokines such as IL-6 and C-reactive protein (CRP). Also,
within the subsets of adipose tissue pro-inflammatory macrophages (phenotype M1), it
has been shown that they replace anti-inflammatory macrophages (phenotype M2).
Adipose tissue also produces a large amount of adipokines that act as signaling
molecules, with a broad range of effects on many organ systems, including the lungs.
Therefore, a possible underlying physiopathological mechanism that explains the effect
of obesity on the severity of SARS-CoV-2 infection may be due to anomalies in the
production of adipokines by fatty tissue, contributing to the condition called a
“cytokine storm”, which characterizes the severe form of COVID 19. Also, expression
of the gene (SARS-CoV-2 receptor) is greater in visceral and subcutaneous adipose
tissue than in lung tissue, an important target affected by SARS-CoV-2 infection. This
suggests a mechanism by which excess adiposity may lead to greater severity of
infection in patients with COVID-19. The production of these adipokines and proinflammatory factors of adipose tissue, as well as its importance in the severity of
COVID-19, are analyzed in this chapter, proposing these cytokines as possible markers
of metabolic and immunological diseases.
Keywords: Adipokines, Adiponectin, Cancer, COVID-19, Cytokine Storm, Immunology, Inflammation, Leptin, Obesity, Resistin, SARS-COV-2.
