Look Beyond Gluten in Short Stature with Celiac Disease - A Prospective, Interventional Study
INDIAN JOURNAL OF PEDIATRICS
Authors: Walia, Rama; Singh, Amandeep; Aggarwal, Anshita; Thapa, Baburam; Guptasarma, Manni Luthra; Bhansali, Anil; Khandelwal, Niranjan
Abstract
Objective Short stature (SS) is a common manifestation of celiac disease (CD). After starting gluten free diet (GFD), children usually have catch-up growth (improvement in height SDS of >1 SD). However, few children in remission, even on GFD, lack catch up growth. This study was planned to assess the growth hormone (GH) axis and the prevalence of anti-pituitary antibodies in such patients. Methods It was a single-centre, prospective study. Patients with CD in remission for the last 1 y, having SS and lacking catch-up growth, were included after excluding other common causes of SS. GH dynamics were studied using stimulation tests: Insulin tolerance test, clonidine stimulation test, and glucagon stimulation test. GH deficiency (GHD) was defined as non-stimulable response to 2 GH stimulation tests. Anti-pituitary antibodies were analysed in these patients using rat pituitary extract as antigen. Results Ten patients (8 girls), with a mean age of 10 +/- 2.8 y, in serological remission for CD and lacking catch-up growth, were enrolled. All had a height SDS of < -2. Fifteen age matched children with CD and adequate catch up growth served as controls. GHD was seen in 7 patients (70%), out of whom 2 received GH therapy and had an improvement in the height SDS from -2.7 to -1.4 and from -2.1 to 2.4 (over 1 y), respectively. Anti-pituitary antibodies were seen in significant titres in 55.5% of the cases and 40% of the controls. Conclusions Children with CD in remission but lacking catch-up growth should be evaluated for GHD.
Differential GLP-1R Binding and Activation by Peptide and Non-peptide Agonists
MOLECULAR CELL
Authors: Zhang, Xin; Belousoff, Matthew J.; Zhao, Peishen; Kooistra, Albert J.; Truong, Tin T.; Ang, Sheng Yu; Underwood, Christina Rye; Egebjerg, Thomas; Senel, Petr; Stewart, Gregory D.; Liang, Yi-Lynn; Glukhova, Alisa; Venugopal, Hari; Christopoulos, Arthur; Furness, Sebastian G. B.; Miller, Laurence J.; Reedtz-Runge, Steffen; Langmead, Christopher J.; Gloriam, David E.; Danev, Radostin; Sexton, Patrick M.; Wootten, Denise
Abstract
Peptide drugs targeting class B1 G-protein-coupled receptors (GPCRs) can treat multiple diseases; however, there remains substantial interest in the development of orally delivered non-peptide drugs. Here, we reveal unexpected overlap between signaling and regulation of the glucagon-like peptide-1 (GLP-1) receptor by the non-peptide agonist PF 06882961 and GLP-1 that was not observed for another compound, CHU-128. Compounds from these patent series, including PF 06882961, are currently in clinical trials for treatment of type 2 diabetes. High-resolution cryoelectron microscopy (cryo-EM) structures reveal that the binding sites for PF 06882961 and GLP-1 substantially overlap, whereas CHU-128 adopts a unique binding mode with a more open receptor conformation at the extracellular face. Structural differences involving extensive water-mediated hydrogen bond networks could be correlated to functional data to understand how PF 06882961, but not CHU-128, can closely mimic the pharmacological properties of GLP-1. These findings will facilitate rational structure-based discovery of non-peptide agonists targeting class B GPCRs.