High glucose impairs acetylcholine-mediated vasodilation in isolated arteries from Mourning doves (Z. macroura)

Ultrasound-responsive taurine lipid nanoparticles attenuate oxidative stress and promote macrophage polarization for diabetic wound healing

Diabetic wound healing presents a significant clinical challenge due to disrupted neuro-immune interactions. This study identifies the α7 nicotinic acetylcholine receptor (α7nAChR) as a key regulator of wound repair by linking cholinergic signaling to macrophage reprogramming. GEO analysis of diabetic foot ulcer (DFU) microenvironments revealed neuronal loss, M1 macrophage dominance, and chronic inflammation, all driven by impaired acetylcholine (ACh) secretion and α7nAChR inactivation. Mechanistically, taurine (TA) restored PC12 cell function under high glucose conditions by activating AMPK, alleviating oxidative and endoplasmic reticulum stress, and promoting ACh production. ACh activated macrophage α7nAChR, modulating M1/M2 polarization through JAK2/STAT3 activation and NF-κB suppression. To enhance TA bioavailability, ultrasound-responsive Ccr2-targeted TA nanoparticles (Ccr2@TA@LNP) were developed for site-specific delivery via Ccl2/Ccr2 chemotaxis. In diabetic neuropathy (DPN) mice, Ccr2@TA@LNP accelerated wound healing by increasing ACh levels, enhancing α7nAChR/CD206 expression, and reducing Ccl2-mediated inflammation. By integrating neuroprotection, macrophage reprogramming, and targeted nanotherapy, this study highlights TA as a multi-target agent that restores neuro-immune balance through the AMPK/α7nAChR/JAK2-STAT3 axis, offering a novel therapeutic strategy for diabetic wound treatment.

A Four-Week Urban Diet Impairs Vasodilation but Not Nutritional Physiology in Wild-Caught Mourning Doves (Zenaida macroura)

AbstractBirds living in urban areas routinely consume anthropogenic foods, but the physiological consequences of this consumption are poorly understood. To address this question, we investigated the effects of an urban diet (UD) in wild, urban-caught mourning doves in a controlled environment. Since anthropogenic foods often contain a high proportion of refined carbohydrate and fat, we predicted that UD consumption alters body mass as well as plasma and tissue metabolites and that it impairs vasodilation. To test this prediction, we compared body mass, various nutritional physiology parameters, and peripheral vasodilation of doves fed an UD (1∶1 ratio of bird seeds and french fries; [Formula: see text]) with those of doves receiving a control diet (CON, bird seed diet; [Formula: see text]) for 4 wk. At the end of the dietary manipulation period, birds were euthanized, and we dissected cranial tibial arteries to measure ex vivo vasodilation in response to acetylcholine treatment after phenylephrine-induced vasoconstriction. We also collected cardiac blood as well as liver, pectoralis, and gastrocnemius muscle samples to measure nutritional metabolite concentrations. Vasodilation of tibial arteries was impaired in UD- compared to CON-fed birds ([Formula: see text]), suggesting the potential for UD consumption to alter cardiovascular function. Body mass, plasma osmolality, glucose, sodium, insulin, triglyceride, uric acid, liver glycogen and triglycerides, and muscle glycogen did not differ between groups. The results suggest that short-term consumption of a diet composed of 50% anthropogenic foods is not associated with major metabolic perturbations in urban mourning doves.