Abstract
According to the most recent WHO report in 2022, about 16% of people were classified as obese. Obesity is an inflammatory-mediated condition manifested by accelerated lipogenesis and accumulation of excessive amounts of fat around the viscera and, in some cases, surrounds the male gonads. Thus, obesity is considered one of the major causes of male infertility. Many environmental toxicants known as obesogens are connected to obesity progression via disturbing hormonal profile, interrupting the cellular metabolism and subsequently leading to the development of fat tissue. Such toxicants like bisphenol A, a plastic derivative, as well as dioxins, which are byproduct of incomplete combustion or industrial processes. Interestingly, these types of toxicants, in addition to others like polycyclic aromatic hydrocarbons and polychlorinated biphenyls, are defined as ligands of aryl hydrocarbon receptor (AhR). AhR has critical roles in immunity, metabolism, reproduction, and cancer biology, and it is expressed in immune cells like T/B lymphocytes, macrophages, and dendritic cells. The effect of AhR on immunity is dependent on the ligand, which in turn could activate macrophage-induced obesity. Many of the ligands of AhR can be exogenous or endogenous (kynurenine and indole derivatives) and affect reproductive functions, such as spermatogenesis and oocyte maturation. There are also natural antagonists to AhR, including resveratrol, showing potential to play a role in fertility governance. .Currently, to connect the roles of AhR in obesity-induced male infertility. This review aims to elucidate the physiological/toxicological roles of AhR in obesity initiation and male infertility.

Key words: Aryl hydrocarbon receptor; Male Infertility; Metabolic infertility; Obesity.