The cross-talk between leptin and circadian rhythm signaling proteins in physiological processes: a systematic review

Background: Today modern lifestyles and especially disrupted sleep patterns cause circadian clock rhythm impairments that may be linked with the leptin signaling pathway which subsequently alter a wide range of metabolic processes and have significant health burdens on societies. Nevertheless, there is not any systematic review regarding circadian clock genes and proteins, leptin, and the related signaling pathways. Methods: Accordingly, we systematically reviewed circadian clock proteins, leptin, and molecular mechanisms between them by searching Pubmed, Scopus, ProQuest, Web of Sciences, and also Google Scholar until September 2022. After considering inclusion and exclusion criteria, twenty animal model studies were selected as there were not any clinical trial articles about the related molecular pathways. Then the risk of bias for each paper was assessed. Results: The results clarified the reciprocal interconnected relationship between the circadian clock genes and leptin and more profoundly, revealed engaged molecular mechanisms and factors. Also, the role of these molecular mechanisms was explained in different physiological processes such as metabolism in the hypothalamus and corresponding peripheral organs. Conclusions: All this may demonstrate that these signaling pathways and affecting elements should be considered in the prevention and choosing of new therapeutic targets for related disorders especially obesity and metabolic impairments.