A Diabetes Drug That Switches Itself On With Blood Sugar: Live Bacteria Secreting GLP1 on Demand
Scientists have engineered E. coli to secrete GLP1 automatically when blood sugar runs high, improving glucose control in mice and in macaques; human trials are still a long way off, but the work opens up the prospect of a living drug that doses on demand.
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A fixed-dose drug can never keep up with moving blood sugar
Diabetes is a common disease with a global footprint; the WHO estimates that roughly one in nine people is affected. Existing GLP1 agonists such as Ozempic and Wegovy work well, but there is a fundamental mismatch: the dosing regimen is fixed while blood sugar moves constantly. Overshoot the dose and the side effects are amplified. So the team set out to build a living bacterium that could sense blood sugar and release the therapeutic molecule on demand — a drug that works only when it is needed.
A molecular brake makes the bacteria produce the drug only when glucose is high
The team engineered E. coli with a regulatory circuit they call a molecular brake. When blood sugar is low, the brake holds GLP1 synthesis in the off state; when blood sugar rises, a signalling molecule is produced inside the bacterium, the brake releases and GLP1 secretion begins; once blood sugar falls back, the signal weakens and the brake goes back on. This closed loop targets the defect in fixed dosing directly, matching the dose delivered to the real-time blood sugar level — dynamic regulation of the kind the body itself performs. The design is nicknamed Gift, for glucose-responsive bacteria.
The live bacteria survive the stomach and still work, in macaques too
The researchers fed Gift orally to diabetic mice and to macaques. In both animals the bacteria still worked after passing through the stomach and reaching the gut: under high blood sugar the circuit was strongly activated, GLP1 was secreted, and blood sugar control and glucose tolerance improved markedly. On top of that, treated animals showed lower levels of fat accumulation in the liver and less kidney and colon damage than untreated controls, and the mice lost body weight and body fat. GLP1 itself has a weight-loss effect, but these results support the conclusion that delivery by live bacteria is effective, and that it may bring extra benefit to diabetes patients, who are often also overweight.
This is not one glucose-lowering drug, it is a platform for living medicines
Guan stresses that the work is still a considerable distance from human trials. The team needs to work out how long the bacteria survive in the body, how long their effect lasts, and how often they would have to be taken by mouth, and it needs to establish long-term safety. But the larger imagination here is the platform: the same sense-and-respond bacterial system could in future be programmed to recognise the signals of other diseases and secrete the corresponding therapeutic molecules, giving rise to a new generation of smart, self-regulating living medicines. That, rather than a single glucose-lowering therapy, is the ultimate goal of the work.
— Ninzi GuanWhere mountain lions are present, deer-vehicle collisions drop by 67%
Combining vehicle-deer collision data with GPS collar and camera trap records, researchers found that the presence of mountain lions — also called cougars or pumas — cuts the probability of a deer-vehicle collision by 67%. Deer actively avoid the forest edges where mountain lions tend to be active, roadsides included, and because mountain lions are night hunters, deer also become less active at night — which is exactly when many collisions happen. The researchers hope that spelling out this unexpected effect will help build public support for coexisting with large carnivores.
A water drop does not just hit rock, it sets the rock ringing
Past work on erosion by water drops relied mainly on high-speed cameras, which cannot resolve how force is distributed after impact. These researchers switched to surface strain sensors, measuring the deformation of the material beneath a glass plate. They found that in the first 2 milliseconds after a drop lands it generates powerful forces, enough to begin damaging the surface; then, from 2 to 20 milliseconds, the material and the water vibrate together at close to the natural resonant frequency of rock, which may extend microcracks and so accelerate erosion. That offers a new microscopic mechanism for understanding how landscapes evolve.
The eclipse sun is dimmer and can still burn through your retina
During an eclipse the sun is partly covered and the light is weaker, but the harm remains — looking straight at it can cause permanent retinal burns. There are two safe approaches. One is eclipse glasses that meet the ISO standard, whose filters pass only a tiny amount of light, so that with them on you can barely see ordinary objects. The other is indirect projection: use a pinhole camera, a colander, or the gaps between leaves under a tree to project an image of the sun onto the ground. Never look through a telescope or a camera directly unless it is fitted with a professional filter.
— Lizzie GibneyTo study the corona, two satellites build an artificial eclipse in space
The scientific value of an eclipse is that it lets you observe the corona, which is normally drowned out by the sun's glare. The corona is the sun's outer magnetic atmosphere, reaching temperatures of several million degrees Celsius, far hotter than the roughly 5000 degrees Celsius of the solar surface, and it is the source of solar storms. Space weather can disrupt satellites, power grids and trains, which is why understanding the corona matters so much. The European Space Agency launched the Proba-3 mission specifically for this: two satellites flying one in front of the other create an artificial eclipse so that the corona can be studied continuously. Eclipses seen from the ground remain a rare opportunity.
— Lizzie GibneyIn their own words · checked verbatim
One major challenge is that.Blood glucose goes up and down throughout the day, depending on meals.Physical activity and many other factors.
In mice, we found that the glucose responsive circuit was strongly activated.Under diabetic conditions.
Ninzi Guan3:00
Ultimately, our goal is not just to develop one treatment.But to explore a new generation of smart.Self regulating living medicines.
Ninzi Guan4:40
They found that the presence of mountain lions also known as cougars or pus is,Associated with a 67% reduction in the probability of a deer vehicle collision.
there is no safe way of doing it, you can't reflect it of anything.Definitely don't look through.Butocularlls or any kind of telescope like that.
Lizzie Gibney10:30
The key thing that you can do during eclipse that you can't do normally is see the sun's corona, so that's this kind of.Magnetic atmosphere that is around the sun, extremely hot.
Lizzie Gibney16:43
Figures
| WHO estimate of diabetes prevalence | About one in nine | 0:30 |
| Drop in deer-vehicle collision probability where mountain lions are present | 67% | 6:30 |
| Share of the sun covered in the eclipse, London | About 90% | 10:00 |
| Share of the sun covered in the eclipse, New York | About 10% | 10:30 |
| Temperature of the solar surface | About 5000 degrees Celsius | 17:00 |
| Temperature of the corona | About several million degrees Celsius | 17:15 |
Glossary
- GLP-1 (glucagon-like peptide-1)
- A hormone secreted in the gut that stimulates insulin release and suppresses appetite; a major target for glucose-lowering and weight-loss drugs.
- Molecular brake
- A repressive switch in a gene circuit that blocks protein expression in the absence of a stimulus.
- Proba-3
- An ESA satellite formation mission in which two spacecraft occult the sun to create an artificial eclipse for observing the corona.
How to listen
Metabolic disease researchers, biotech founders, investors watching living medicines, and people with diabetes.
The research highlights and the eclipse segment can be skipped; the probiotic story alone is enough.