MULTIFACTORIAL DETERMINANTS OF OBESITY: THE ROLES OF HORMONES, GENETICS, INFLAMMATION AND GUT MICROBIOTA – REVIEW
DOI:
https://doi.org/10.31435/ijitss.4(48).2025.4311Keywords:
Obesity, Hormones, Gut Microbiota, Inflammation, TreatmentAbstract
Obesity is a multifactorial chronic disease resulting from the interaction of genetic, hormonal, inflammatory, and microbial factors. While caloric imbalance contributes to its pathogenesis, pathways involving molecular mechanisms—such as leptin–melanocortin pathway dysfunction, adipokine dysregulation, and microbiota-induced inflammation—are also significant. Adipose tissue inflammation is characterized by macrophage infiltration, activation of MAPK and NF-κB pathways, and abnormal adipokine secretion, all of which lead to insulin resistance and metabolic dysfunction. Genetic factors, including mutations in the LEP, LEPR, POMC, and MC4R genes, can disrupt appetite regulation and predispose individuals to early-onset obesity. Syndromic forms of obesity, such as Prader–Willi and Bardet–Biedl syndromes, further highlight chromosomal influences. Hormonal imbalances, including those involving ghrelin, GLP-1, and CCK, also affect energy expenditure and appetite regulation. Additionally, gut dysbiosis contributes to systemic inflammation through increased levels of lipopolysaccharides (LPS) and decreased production of short-chain fatty acids, which maintain metabolic endotoxemia. These patterns of evidence underscore the need for integrative interventions targeting endocrine, inflammatory, and microbial pathways. Further research is required to clarify gene– microbiota–hormone interactions and to develop personalized therapeutic intervention.
References
Alhabeeb, H., Alfaiz, A., Kutbi, E., Alshahrani, D., Alsuhail, A., Alrajhi, S., Alotaibi, N., Alotaibi, K., Alamri, S., Alghamdi, S., & Aljohani, N. (2021). Gut hormones in health and obesity: The upcoming role of short chain fatty acids. In Nutrients (Vol. 13, Issue 2). https://doi.org/10.3390/nu13020481
Amabebe, E., Robert, F. O., Agbalalah, T., & Orubu, E. S. F. (2020). Microbial dysbiosis-induced obesity: role of gut microbiota in homoeostasis of energy metabolism. British Journal of Nutrition. https://doi.org/10.1017/S0007114520000380
Aruwa, C. E., & Sabiu, S. (2024). Adipose tissue inflammation linked to obesity: A review of current understanding, therapies and relevance of phyto-therapeutics. In Heliyon (Vol. 10, Issue 1). Elsevier Ltd. https://doi.org/10.1016/j.heliyon.2023.e23114
Attaye, I., van Oppenraaij, S., Warmbrunn, M. V., & Nieuwdorp, M. (2022). The role of the gut microbiota on the beneficial effects of ketogenic diets. In Nutrients (Vol. 14, Issue 1). https://doi.org/10.3390/nu14010191
Baothman, O. A., Zamzami, M. A., Taher, I., Abubaker, J., & Abu-Farha, M. (2016). The role of Gut Microbiota in the development of obesity and Diabetes. In Lipids in Health and Disease (Vol. 15, Issue 1). https://doi.org/10.1186/s12944-016-0278-4
Broeders, E. P. M., Nascimento, E. B. M., Havekes, B., Brans, B., Roumans, K. H. M., Tailleux, A., Schaart, G., Kouach, M., Charton, J., Deprez, B., Bouvy, N. D., Mottaghy, F., Staels, B., Van Marken Lichtenbelt, W. D., & Schrauwen, P. (2015). The bile acid chenodeoxycholic acid increases human brown adipose tissue activity. Cell Metabolism, 22(3). https://doi.org/10.1016/j.cmet.2015.07.002
Chakraborti, C. K. (2015). New-found link between microbiota and obesity. Baishideng Publishing Group. https://doi.org/https://doi.org/10.4291/wjgp.v6.i4.110
Cheng, Z., Zhang, L., Yang, L., & Chu, H. (2022). The critical role of gut microbiota in obesity. In Frontiers in Endocrinology (Vol. 13). https://doi.org/10.3389/fendo.2022.1025706
Coppola, S., Avagliano, C., Calignano, A., & Canani, R. B. (2021). The Protective Role of Butyrate against Obesity and Obesity-Related Diseases. Molecules. https://doi.org/10.3390/molecules26030682
Ecklu-Mensah, G., Choo-Kang, C., Maseng, M. G., Donato, S., Bovet, P., Viswanathan, B., Bedu-Addo, K., Plange-Rhule, J., Boateng, P. O., Forrester, T., Williams, M., Lambert, E., Rae, D., Sinyanya, N., Luke, A., Layden, B., OKeefe, S., Gilbert, J., & Dugas, L. (2023). Gut microbiota and fecal short chain fatty acids differ with adiposity and country of origin: the METS-microbiome study. Nature Communications. https://doi.org/10.1038/s41467-023-40874-x
Ellulu, M. S., Patimah, I., Khaza’ai, H., Rahmat, A., & Abed, Y. (2017). Obesity & inflammation: The linking mechanism & the complications. Archives of Medical Science, 13(4), 851–863. https://doi.org/10.5114/aoms.2016.58928
Fang, S., Suh, J. M., Reilly, S. M., Yu, E., Osborn, O., Lackey, D., Yoshihara, E., Perino, A., Jacinto, S., Lukasheva, Y., Atkins, A. R., Khvat, A., Schnabl, B., Yu, R. T., Brenner, D. A., Coulter, S., Liddle, C., Schoonjans, K., Olefsky, J. M., … Evans, R. M. (2015). Intestinal FXR agonism promotes adipose tissue browning and reduces obesity and insulin resistance. Nature Medicine, 21(2). https://doi.org/10.1038/nm.3760
Gaber, M., Wilson, A. S., Millen, A., Hovey, K., LaMonte, M. J., Wactawski-Wende, J., Ochs-Balcom, H. M., & Cook, K. L. (2024). Visceral adiposity in postmenopausal women is associated with a pro-inflammatory gut microbiome and immunogenic metabolic endotoxemia. Microbiome. https://doi.org/10.1186/s40168-024-01901-1
Hastuti, P. (2022). Obesity and the role of genetic polymorphism: A review of genes as the risk of obesity. Journal of the Medical Sciences (Berkala Ilmu Kedokteran), 54(2). https://doi.org/10.19106/jmedsci005402202209
Huang, M., Huang, M., Liu, L., Yang, F., He, C., Sun, Y.-C., Jiao, Y.-R., Xiang, T., Hou, J., Chen, K.-X., He, W., Wei, J., Chen, H.-L., Li, X., Zeng, C., Lei, G.-H., Jun-li, C., Huang, M., Huang, M., … Jun-li, C. (2025). Gut Microbiota Modulates ObesityAssociated Skeletal Deterioration Through Macrophage Aging and Grancalcin Secretion. Wiley. https://doi.org/https://doi.org/10.1002/advs.202502634
Kaila, B., & Raman, M. (2008). Obesity: A review of pathogenesis and management strategies. In Canadian Journal of Gastroenterology (Vol. 22, Issue 1). https://doi.org/10.1155/2008/609039
Khanna, D., Khanna, S., Khanna, P., Kahar, P., & Patel, B. M. (2022). Obesity: A Chronic Low-Grade Inflammation and Its Markers. Cureus. https://doi.org/10.7759/cureus.22711
Kimura, I., Inoue, D., Hirano, K., & Tsujimoto, G. (2014). The SCFA Receptor GPR43 and Energy Metabolism. Frontiers in Endocrinology. https://doi.org/10.3389/fendo.2014.00085
Kopczynska, J., & Kowalczyk, M. (2024). The potential of short-chain fatty acid epigenetic regulation in chronic low-grade inflammation and obesity. Frontiers in Immunology. https://doi.org/10.3389/fimmu.2024.1380476
Li, L., Zhao, X., Abdugheni, R., Yu, F., Zhao, Y., Ma, B. F., Yang, Z., Li, R., Li, Y., Maimaitiyiming, Y., & Maimaiti, M. (2024). Gut microbiota changes associated with low-carbohydrate diet intervention for obesity. Open Life Sciences, 19(1). https://doi.org/10.1515/biol-2022-0803
Lin, X., & Li, H. (2021). Obesity: Epidemiology, Pathophysiology, and Therapeutics. In Frontiers in Endocrinology (Vol. 12). https://doi.org/10.3389/fendo.2021.706978
Mahmoud, R., Kimonis, V., & Butler, M. G. (2022). Genetics of Obesity in Humans: A Clinical Review. In International Journal of Molecular Sciences (Vol. 23, Issue 19). https://doi.org/10.3390/ijms231911005
Marić, G., Gazibara, T., Zaletel, I., Labudović Borović, M., Tomanović, N., Cirić, M., & Puškaš, N. (2014). The role of gut hormones in appetite regulation (review). In Acta Physiologica Hungarica (Vol. 101, Issue 4). https://doi.org/10.1556/APhysiol.101.2014.4.1
Mlynarska, E., Bojdo, K., Bulicz, A., Frankenstein, H., Gsior, M., Kustosik, N., Rysz, J., & Franczyk, B. (2025). Obesity as a Multifactorial Chronic Disease: Molecular Mechanisms, Systemic Impact, and Emerging Digital Interventions. Caister Academic Press. https://doi.org/https://doi.org/10.3390/cimb47100787
Muscogiuri, G., Verde, L., Sulu, C., Katsiki, N., Hassapidou, M., Frias-Toral, E., Cucalón, G., Pazderska, A., Yumuk, V. D., Colao, A., & Barrea, L. (2022). Mediterranean Diet and Obesity-related Disorders: What is the Evidence? In Current Obesity Reports (Vol. 11, Issue 4). https://doi.org/10.1007/s13679-022-00481-1
Ngamsamer, C., Sirivarasai, J., & Sutjarit, N. (2022). The Benefits of Anthocyanins against Obesity-Induced Inflammation. In Biomolecules (Vol. 12, Issue 6). https://doi.org/10.3390/biom12060852
Nikulina, A. o. (2024). Significance of single-nucleotide variants of anorexigenic hormone genes in childhood obesity. SE “Dnipropetrovsk Medical Academy of Health Ministry of Ukraine.” https://doi.org/https://doi.org/10.26641/2307-0404.2024.1.300508
Pelc, A., Fic, W., Typrowicz, T., & Polak-Szczybyo, E. (2025). Physiological Mechanisms of and Therapeutic Approaches to the Gut Microbiome and Low-Grade Inflammation in Obesity. Current Issues in Molecular Biology. https://doi.org/10.3390/cimb47080637
Puljiz, Z., Kumric, M., Vrdoljak, J., Martinovic, D., Ticinovic Kurir, T., Krnic, M. O., Urlic, H., Puljiz, Z., Zucko, J., Dumanic, P., Mikolasevic, I., & Bozic, J. (2023). Obesity, Gut Microbiota, and Metabolome: From Pathophysiology to Nutritional Interventions. In Nutrients (Vol. 15, Issue 10). https://doi.org/10.3390/nu15102236
Randeni, N., Bordiga, M., & Xu, B. (2024). A Comprehensive Review of the Triangular Relationship among DietGut MicrobiotaInflammation. International Journal of Molecular Sciences. https://doi.org/10.3390/ijms25179366
Ridlon, J. M., Kang, D. J., & Hylemon, P. B. (2006). Bile salt biotransformations by human intestinal bacteria. In Journal of Lipid Research (Vol. 47, Issue 2). https://doi.org/10.1194/jlr.R500013-JLR200
Rohm, T. V., Meier, D. T., Olefsky, J. M., & Donath, M. Y. (2022). Inflammation in obesity, diabetes, and related disorders. Immunity, 55(1), 31–55. https://doi.org/10.1016/J.IMMUNI.2021.12.013
Sam, A. H., Troke, R. C., Tan, T. M., & Bewick, G. A. (2012). The role of the gut/brain axis in modulating food intake. In Neuropharmacology (Vol. 63, Issue 1). https://doi.org/10.1016/j.neuropharm.2011.10.008
Schwartz, M. W., Seeley, R. J., Zeltser, L. M., Drewnowski, A., Ravussin, E., Redman, L. M., & Leibel, R. L. (2017). Obesity pathogenesis: An endocrine society scientific statement. Endocrine Reviews, 38(4). https://doi.org/10.1210/ER.2017-00111
Skoracka, K., Hryhorowicz, S., Schulz, P., Zawada, A. E., Rychter, A. M., Somski, R., Dobrowolska, A., & Krela-Kamierczak, I. (2025). The role of leptin and ghrelin in the regulation of appetite in obesity. Elsevier BV. https://doi.org/https://doi.org/10.1016/j.peptides.2025.171367
Suzuki, K., Simpson, K. A., Minnion, J. S., Shillito, J. C., & Bloom, S. R. (2010). The role of gut hormones and the hypothalamus in appetite regulation. In Endocrine Journal (Vol. 57, Issue 5). https://doi.org/10.1507/endocrj.K10E-077
Valls, Y., Arshad, M., Abdalbaqi, M., Inman, C. K., Ahmad, A., Drou, N., Gunsalus, K. C., Ali, R., Tahlak, M., Abdulle, A., Valls, Y., Arshad, M., Abdalbaqi, M., Inman, C. K., Ahmad, A., Drou, N., Gunsalus, K. C., Ali, R., Tahlak, M., & Abdulle, A. (2024). The infants gut microbiome: setting the stage for the early onset of obesity. Frontiers Media. https://doi.org/https://doi.org/10.3389/fmicb.2024.1371292
Vourdoumpa, A., Paltoglou, G., & Charmandari, E. (2023). The Genetic Basis of Childhood Obesity: A Systematic Review. In Nutrients (Vol. 15, Issue 6). https://doi.org/10.3390/nu15061416
Weisberg, S. P., McCann, D., Desai, M., Rosenbaum, M., Leibel, R. L., & Ferrante, A. W. (2003). Obesity is associated with macrophage accumulation in adipose tissue. Journal of Clinical Investigation, 112(12). https://doi.org/10.1172/JCI200319246
Wu, H., & Ballantyne, C. M. (2020). Metabolic Inflammation and Insulin Resistance in Obesity. In Circulation Research (Vol. 126, Issue 11, pp. 1549–1564). Lippincott Williams and Wilkins. https://doi.org/10.1161/CIRCRESAHA.119.315896
Zhang, C. X. W., Candia, A. A., & Sferruzzi-Perri, A. N. (2024). Placental inflammation, oxidative stress, and fetal outcomes in maternal obesity. Trends in Endocrinology & Metabolism, 35(7), 638–647. https://doi.org/10.1016/J.TEM.2024.02.002
Zhang, S., Zhang, Y., Li, J., Wang, X., Zhang, M., Du, M., Jiang, W., & Li, C. (2024). Butyrate and Propionate are Negatively Correlated with Obesity and Glucose Levels in Patients with Type 2 Diabetes and Obesity. Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy. https://doi.org/10.2147/DMSO.S434499
Zsálig, D., Berta, A., Tóth, V., Szabó, Z., Simon, K., Figler, M., Pusztafalvi, H., & Polyák, É. (2023). A Review of the Relationship between Gut Microbiome and Obesity. In Applied Sciences (Switzerland) (Vol. 13, Issue 1). https://doi.org/10.3390/app13010610
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