Transdermal insulin delivery via OP polymer, brain language processing, and early dog domestication explored in Nature Podcast

In this episode, researchers outline a promising transdermal insulin delivery method using a pH-responsive polymer called OP, which navigates the skin’s barrier to reach circulation. The podcast also investigates how language is represented in the brain, revealing surprising similarities in neural processing of native and foreign speech, and it even delves into the deep history of dogs, showing early skull diversity and connections between human and canine populations. Additionally, there is a briefing on COP30 climate negotiations and predictions for when global emissions might peak. This episode weaves together biomedical innovation, brain science, archaeology, and climate policy to highlight how science unravels complex biological and environmental questions.

Overview

The Nature Podcast presents a multi-faceted look at recent research spanning biomedicine, neuroscience, archaeology, and climate science. The central thread is how new data from diverse fields can change our understanding of human health, language, and our relationship with animals, particularly dogs, while also situating these advances within global policy debates about emissions and climate action.

Transdermal insulin delivery and OP polymer

Researchers from Zhejiang University report a novel polymer, poly2N-oxide NN-dimethyl amino ethyl methacrylate (OP), engineered to exploit the skin’s pH gradient. The polymer becomes positively charged in the skin’s acidic surface, enabling binding to lipid molecules. As it penetrates into more neutral sub-layers, OP loses its charge, releasing its insulin cargo into circulation. In mice, insulin tethered to OP (OPI) reduced glucose within 30 minutes, reaching near-normal levels within an hour, and achieved similar effects in mini pigs over a two-hour period without noticeable skin damage. While promising, questions about long-term safety and dosing precision remain, but the approach could potentially be adapted for other large biomolecules. “This performance is almost as quick as injected insulin,” - Yu Qing Shen, Zhejiang University.

Language in the brain: universal building blocks with native-foreign differences

Neuroscientist Eddie Chang and colleagues examined how the brain processes phonemes, syllables, and words in native versus unfamiliar languages. Using intracranial recordings from epilepsy patients undergoing clinical monitoring, they found that individual phonetic elements are represented similarly across languages, yet the brain parses speech into words in a native language, a process reflected by dips in neural activity between words rather than a continuous signal. The superior temporal gyrus emerges as a key hub, handling both native and second languages, suggesting shared neural machinery that adapts with experience. A notable takeaway is that bilinguals show complex coding for multiple languages within the same brain region, underscoring the brain’s plasticity for language learning and maintenance. “Regardless if you were listening to your native or foreign language, actually, the brain activity looked remarkably similar,” - Eddie Chang, University of California, San Francisco.

Dogs through time: skull morphology and ancient human-dog relationships

The podcast covers two connected studies on dog domestication and dispersal. One paper classifies ancient skull shapes to separate dog-like from wolf-like specimens, revealing dog-like skulls around 11,000 years ago and an early explosion in skull shape diversity, suggesting purposeful breeding or intense selection long before the Victorian era. A second genetic study sequences genomes from 17 dogs dating back 10,000 years, linking dog populations to human ancestries and showing dogs tracked human migrations; in some cases dogs moved with humans, while in others dogs appear to have been traded between populations. Together, these findings illuminate the deep, intertwined history of dogs and humans and hint at varied pathways to domestication. “The diversity of dog shapes happened quite early,” - researchers discussing skull morphology findings.

Climate briefing: emissions peaks and policy context

The Nature Briefing segment discusses COP30 in Brazil and uncertain timelines for peak emissions, with China now the largest emitter but potentially peaking soon due to demand shifts in cement and steel, plus heavy investment in renewables. Projections range from 2030 to 2035 for peak emissions, after which steep reductions are required to meet 1.5°C or 2°C targets. The discussion uses a metaphor about managing greenhouse gases like a swimming pool—turning off the hose while enlarging the drain and learning to swim—to emphasize the multi-faceted effort needed for climate stabilization.