Fig. 5: Cysteine-elimination-induced browning and weight loss requires noradrenergic signalling.
From: Cysteine depletion triggers adipose tissue thermogenesis and weight loss
a, Tissue clearing and whole-brain c-Fos immunolabelling approach using iDISCO+ and CLEARMAP in Cth−/−mice fed CTRL or CysF for 5 days. b, Scheme of the thermosensory information inflow into the brain and the thermogenic outflow to periphery, highlighting the key canonical sites responsible for a thermogenic response. LPBN, lateral parabrachial nucleus; MPOA, medial preoptic area; DMH, dorsomedial hypothalamus; PVH, paraventricular hypothalamus; RPA, raphe palladus; DRN/vlPAG, dorsal raphe nucleus/ventrolateral portion of the periaqueductal grey. c, Automated analysis of c-Fos+ cell distribution in Cth−/− brains collected after 5 days CTRL (n = 6) or CysF feeding (n = 5). Panels show the reference annotation (Allen Brain Atlas; ABA) with details from the averaged density maps (5–6 brains averaged) between the two conditions, P value maps (25-μm orthogonal projection) for the canonical thermogenic regions in the brain as coronal projections. First lane shows the LPBN, the entry point of thermosensory information into the brain. Second lane shows the MPOA, the sensory integrator of thermogenic input information. Third, fourth and fifth lanes show DMH, BNST and the vlPAG, respectively; three critical sites for transmitting information received by the MPOA to the SNS-mediated thermogenic outflow. d, Quantification of c-Fos staining in the parabrachial nucleus, MPOA, DMH and BNST of Cth−/− mice after 5 days of CTRL (n = 6) or CysF feeding (n = 5). e) Measurement of noradrenaline by orbitrap MS/MS in the SFAT of Cth+/+ and Cth−/− fed 6 days of CTRL or CysF diet (n = 5 Cth+/+ CTRL, n = 5 Cth+/+ CysF, n = 6 Cth−/− CTRL, n = 6 Cth−/− CysF). f, qPCR gene expression Maoa in SFAT of Cth+/+ (n = 8) and Cth−/− (n = 10) mice fed with CysF diet for 6 days. g,k, Cth−/− mice were fed with CysF diet for 5 days and treated daily with a β-3 adrenergic receptor antagonist (L748337) or vehicle (PBS) (n = 7 per group). g, Percentage body weight change. h, Representative images of hematoxylin and eosin (H&E) staining of SFAT sections (scale bar, 50 μm). i, qPCR gene expression of Ucp1 in BAT depots. j, Immunoblot analysis of lipolysis regulators (pHSL, HSL and ATGL) in BAT samples. Actin is used as a loading control. k, Quantification of pHSL and ATGL signals (n = 6 per group). Data are expressed as mean ± s.e.m. Box plots represent median value and extend to the 25th and 75th percentiles. Whiskers are plotted down to the minimum and up to the maximum value. Statistical differences were calculated by two-way ANOVA with Sidak’s correction for multiple comparisons or by unpaired two-tailed t-tests. Panels a and b created with BioRender.com.
