Journal: Nature Communications

Article Title: Naked mole-rats have distinctive cardiometabolic and genetic adaptations to their underground low-oxygen lifestyles

doi: 10.1038/s41467-024-46470-x

Figure Lengend Snippet: A Representative naked mole-rat and C57/BL6 mouse used in the study. B Langendorff heart ischaemia/reperfusion protocols, figure created with Biorender.com. C Images of representative cardiac sections from C57/BL6 mouse and NMR post I/R. Red colour- viable tissue, white areas- post-infarct scar. D Reduced infarct size in NMR vs C57BL6 post-myocardial ischaemia (20 min) and reperfusion (120 min) protocol ** P = 0.0025. 1 H nuclear magnetic resonance spectroscopy analysis of cardiac metabolites post-20-minute ischaemia in NMR vs C57/BL6 mouse, E elevated total adenine nucleotide pool (sum of ATP + ADP + AMP) * P = 0.039 two-tailed t test, F elevated myocardial glucose *** P = 0.0003 two-tailed, G elevated myocardial lactate ** P = 0.0043 ( H ) reduced effluent lactate ** P = 0.003 * P = 0.0439 two-tailed ( I ) reduced myocardial succinate **** P = 0.0001 and J reduced effluent succinate (1 min reperfusion) * P = 0.041. n = 5/group, Data mean ± SEM. t test two-tailed, data normality tested by Shapiro–Wilk. Source data are provided as a Source Data file.

Article Snippet: Beating hearts were excised from terminally anaesthetised naked mole-rats ( n = 5) and C57/BL6 mice ( n = 5) (Charles River, UK) for Langendorff perfusions as previously described .

Techniques: Nuclear Magnetic Resonance, Spectroscopy, Two Tailed Test

Journal: Science Advances

Article Title: Ultrathin rubbery bio-optoelectronic stimulators for untethered cardiac stimulation

doi: 10.1126/sciadv.adq5061

Figure Lengend Snippet: ( A and B ) RBOES was interfaced to the cadaver heart tissue (A) and the potential response under the light stimulation (1 Hz, 100 ms) (B). ( C and D ) RBOES was interfaced to an intercostal nerve (C) and the potential response under the light stimulation (0.5 Hz, 100 ms) (D). The rubbery semiconducting nanofilm side was directly placed on the tissues to form the interface. The potential signals were extracted using a pair of clamp recording electrodes. ( E ) Schematic of the measurement setup including a Langendorff system that maintained the rat hearts. An adult rat heart was placed in an incubator (37°C and 5% CO 2 ), and oxygenated Krebs-Henseleit buffer reservoir was perfused into the aorta of the heart. A 530-nm LED light was focused through an amplifying lens on the RBOES placed onto the exposed myocardium on the right atrium. ECG electrodes were sutured on the heart to record the signals with a data acquisition system. ( F ) Optical images of the perfused rat heart with the RBOES (marked in the dotted square) and the ECG electrodes. ( G ) Real-time beating rate of the perfused rat heart under consecutive stimulation with targeted beating rates of 120 and 150 bpm (marked in the dotted black line). ( H ) ECG signals of the perfused rat heart under optoelectronic stimulation. The top row shows the ECG signals obtained from prestimulation (0 to 5 s), during stimulation (680 to 685 s), and post-stimulation (771 to 776 s) of 2-Hz light illumination. The bottom row shows ECG signals of the perfused rat heart obtained from prestimulation (600 to 605 s), during stimulation (2240 to 2245 s), and post-stimulation (2262 to 2267 s) of 2.5-Hz light illumination. ( I ) Typical ECG with PQRST waves was observed in the signal during stimulation in (H).

Article Snippet: Cannulated hearts were assembled in the Langendorff perfusion system (Radnoti) and perfused with warm (37°C) oxygenated Krebs-Henseleit buffer (118 mM NaCl, 4.7 mM KCl, 1.2 mM MgSO 4 , 1.25 mM CaCl 2 , 1.2 mM KH 2 PO 4 , 25 mM NaHCO 3 , and 11 mM glucose).

Techniques: