Journal: eLife
Article Title: Hugin-AstA circuitry is a novel central energy sensor that directly regulates sweet sensation in Drosophila and mouse
doi: 10.7554/eLife.108551
Figure Lengend Snippet: ( A ) Blood Neuromedin U (NMU) levels of starved mice refed with 20% sucrose ( t -test; *, p=0.0373; n=6). ( B ) Two-bottle preference tests for starved mice refed with sucrose ( t -test; ***, p=0.0002; n=7). ( C ) Two-bottle preference tests for starved mice with or without intraperitoneal injection of NMU peptide (YFLFRPRN-NH 2 , 4.5 μm/kg) ( t -test; *, p=0.0293; n=7). ( D ) Two-bottle preference tests for indicated starved mice ( t -test; **, p=0.0073; n=6). ( E ) Fiber photometry to record the calcium dynamics of NMU + neurons in the ventromedial hypothalamus (VMH) with GCaMP6m (left) and representative IHC image of expressing GCaMP6m in VMH (right). ( F–G ) Representative trace (left) and heatmaps (right, n=5) showing calcium dynamics of NMU + neurons in the VMH in response to gastric glucose infusion (20% sucrose, 200 μL), which elevates circulating glucose levels independently of oral sensory stimulation. ( H ) Experimental approach to assess calcium signaling in NMU + neurons in the VMH in vitro (left) and representative IHC image of expressing GCaMP6m in VMH (right). ( I–J ) Representative traces and quantification of ex vivo calcium responses of NMU + neurons during the perfusion of glucose with or without TTX ( I ), alloxan ( J ), and phlorizin ( J ) (one-way ANOVA; **, p=0.0049; ***, p=0.0001 for glucose+phlorizin and p=0.0006 for glucose+alloxan; n=6–7). Horizontal black bar represents the duration of indicated glucose solution stimulation. ( K ) Anterograde trans-synaptic tracing of downstream targets of NMU + neurons. NMU + neurons were labeled by GFP expression following injection of a Cre-dependent AAV2/1-DIO-GFP into NMU-Cre mice. This virus undergoes anterograde trans-synaptic transfer to postsynaptic neurons. To enable GFP expression specifically in downstream target regions, an AAV-Cre virus was locally injected into the rNST. As a result, postsynaptic neurons in the rNST receiving input from NMU + neurons were labeled by GFP delivered anterogradely from upstream NMU + neurons. Representative images show that GFP-labeled downstream neurons in the rNST colocalize with Calb2 immunoreactivity, indicating that NMU + neurons preferentially target Calb2 + rNST neurons. ( L ) Fiber photometry to record the calcium dynamics of Calb2 + neurons in the rNST with GCaMP6m (left) and representative IHC image of expressing GCaMP6m in rNST (right). ( M ) Representative traces and quantification of calcium responses of Calb2 + neurons during glucose licking under physiological feeding conditions (500 mM sucrose), with or without NMU administration, assessing downstream modulation of sweet-responsive brainstem circuits ( t -test; ****, p<0.0001; n=6). Student’s t -test and one-way ANOVA followed by post hoc test with Bonferroni correction were used for multiple comparisons when applicable. Figure 7—source data 1. Source data contain numerical values and statistical results for .
Article Snippet: Genetic reagent ( M. musculus ) , NMU-Cre , Shanghai Model Organisms Center , Cat: #NM-KI-200298 , .
Techniques: Injection, Expressing, In Vitro, Ex Vivo, Labeling, Virus
