Cort, short for cortistatin, is a neuropeptide with a wide-range of biological functions. It is highly related to somatostatin and is involved in multiple regulatory pathways. At the endocrine pancreas, it influences insulin secretion, glucose homeostasis, and insulin resistance [4]. In glioma, CORT is identified as an inhibitor of temozolomide (TMZ) resistance by suppressing the NF-κB-MGMT signaling axis. Decreased CORT expression in glioma tissues is associated with a poorer survival rate, and overexpression of CORT can inhibit glioma cell proliferation, migration, and enhance apoptosis of TMZ-resistant cells [5].

In migratory birds like Gray Catbirds, baseline corticosterone (CORT, the primary glucocorticoid in birds) is thought to underlie transitions between fuel catabolism during flight, fuel deposition during stopover, and the initiation of migratory flight. A U-shaped CORT curve over the course of stopover is predicted, with elevated CORT at arrival responding to poor body condition and elevation before departure driving changes in behavior and body condition [1]. In female Cope's gray treefrogs, CORT and its receptors in the brain are related to mate choosiness. Exogenous CORT can rapidly increase choosiness, and there are changes in the expression of glucocorticoid receptors in the brain following CORT treatment, although the causal relationship is not clear [2]. In salamanders, elevated CORT levels via cutaneous patch lead to significantly less tail regeneration after autotomy, while CORT does not directly affect exploratory behavior but may lead to changes in movement patterns due to delayed regeneration [3].

In conclusion, Cort has diverse functions across different species and biological contexts. In birds, it is related to migratory physiology, in amphibians to mate-choice behavior, in salamanders to autotomy-related processes, and in humans, it has implications in glioma treatment. These findings from various research models help us understand the multiple roles of Cort in different biological processes and disease-related conditions.

References:

1. DeSimone, Joely G, Ramirez, Mariamar Gutierrez, Elowe, Cory R, Breuner, Creagh W, Gerson, Alexander R. 2020. Developing a Stopover-CORT hypothesis: Corticosterone predicts body composition and refueling rate in Gray Catbirds during migratory stopover. In Hormones and behavior, 124, 104776. doi:10.1016/j.yhbeh.2020.104776. https://pubmed.ncbi.nlm.nih.gov/32439349/

2. Rodriguez-Santiago, Mariana, Ruppert, Annika, Gall, Megan D, Bee, Mark A, Baugh, Alexander T. 2024. In your CORT: Corticosterone and its receptors in the brain underlie mate choosiness in female Cope's gray treefrogs (Hyla chrysoscelis). In Hormones and behavior, 159, 105477. doi:10.1016/j.yhbeh.2024.105477. https://pubmed.ncbi.nlm.nih.gov/38245919/

3. Lewis, Jacquelyn L, Sullivan, Aaron M. 2020. Salamander stress and duress: the relationship between CORT, autotomy and regeneration, and exploratory behaviour. In Zoology (Jena, Germany), 139, 125751. doi:10.1016/j.zool.2020.125751. https://pubmed.ncbi.nlm.nih.gov/32070799/

4. Chanclón, Beléen, Martínez-Fuentes, Antonio J, Gracia-Navarro, Francisco. 2012. Role of SST, CORT and ghrelin and its receptors at the endocrine pancreas. In Frontiers in endocrinology, 3, 114. doi:10.3389/fendo.2012.00114. https://pubmed.ncbi.nlm.nih.gov/23162532/

5. He, Zongze, Peng, Bo, Wang, Qi, Jia, Ping, Tang, Jian. 2023. Transcriptomic analysis identifies the neuropeptide cortistatin (CORT) as an inhibitor of temozolomide (TMZ) resistance by suppressing the NF-κB-MGMT signaling axis in human glioma. In Genes & diseases, 11, 100977. doi:10.1016/j.gendis.2023.04.017. https://pubmed.ncbi.nlm.nih.gov/38292193/