Anti-obesity compounds, Semaglutide and LiPR, and PrRP do not change the proportion of human and mouse POMC+ neurons

Abstract

Anti-obesity medications (AOMs) have become one of the most prescribed drugs in human medicine. While AOMs are known to impact adult neurogenesis in the hypothalamus, their effects on the functional maturation of hypothalamic neurons remain unexplored. Given that AOMs target neurons in the Medial Basal Hypothalamus (MBH), which play a crucial role in regulating energy homeostasis, we hypothesized that AOMs might influence the functional maturation of these neurons, potentially rewiring the MBH. To investigate this, we exposed hypothalamic neurons derived from human induced pluripotent stem cells (hiPSCs) to Semaglutide and lipidized prolactin-releasing peptide (LiPR), two anti-obesity compounds. Contrary to our expectations, treatment with Semaglutide or LiPR during neuronal maturation did not affect the proportion of anorexigenic, Pro-opiomelanocortin-expressing (POMC+) neurons. Additionally, LiPR did not alter the morphology of POMC+ neurons or the expression of selected genes critical for the metabolism or development of anorexigenic neurons. Furthermore, LiPR did not impact the proportion of adult-generated POMC+ neurons in the mouse MBH. Taken together, these results suggest that AOMs do not influence the functional maturation of anorexigenic hypothalamic neurons.

Fig 1. PrRP does not alter the proportion of POMC+ hiPSC-derived neurons (A) A schematic of the experimental timeline.

(B) Representative confocal images of hiPSC-derived neurons stained as indicated at day 30. (C-H) Representative confocal images of neurons derived from three hiPSC lines and treated with the vehicle (Control, C, E, G) or PrRP (D, F, H) at day 30. (I) Quantification of the POMC+MAP2 + /MAP2 + proportion. (J) Quantification of the POMC+MAP2 + /MAP2 + proportion per hiPSC line (individual data points represent technical replicates). (K-L) RT-qPCR expression of selected genes. Scale bar (s.b.) = 20 µm (B), 50 µm (C-H). n = 3 hiPSC lines. Two-tailed T-Test: *p < 0.05, **p < 0.01, ***p < 0.001. Data are presented as mean ± SEM.

Fig 2. PrRP does not change the number of neurites or POMC expression.

(A) A representative confocal image of POMC+ neurons traced for MAP2 + neurites. (B) Quantification of the number of primary neurites per cell. (C) The ratio of the mean pixel density for POMC and MAP2 in hiPSC-derived neurons. (D) The ratio of the mean pixel density for POMC and DAPI in hiPSC-derived neurons. (E) The mean pixel density of POMC in hiPSC-derived neurons. S.b. = 20 µm. n = 3 hiPSC lines. Two-tailed T-Test: ^#p < 0.06. Data are presented as mean ± SEM.

Fig 3. Semaglutide does not change the proportion of POMC+ hiPSC-derived neurons.

(A) A representative confocal image hiPSC-derived neurons stained as indicated. (B) Quantification of the number of primary neurites per cell. (C) The ratio of the mean pixel density for POMC and MAP2 in hiPSC-derived neurons. (D) The ratio of the mean pixel density for POMC and DAPI in hiPSC-derived neurons. (E) The mean pixel density of POMC in hiPSC-derived neurons. S.b. = 50 µm. n = 3 hiPSC lines. Two-tailed T-Test. Data are presented as mean ± SEM.

Fig 4. LiPR does not alter the number or density of new POMC+ neurons in the mouse MBH.

(A) A schematic of the treatment protocol. (B-C) Representative confocal images of the MBH stained as indicated from Control (B) and LiPR treated (C) mice. (D-E) Quantification of the number (D) and density (E) of BrdU+ cells positive or negative for POMC in the MBH. (F) Mean pixel density of POMC in the MBH and Arc. S.b. = 50 µm. n = 5 mice per group. Two-tailed T-Test: *p < 0.05. Data are presented as mean ± SEM.