CommunityStacking & Switching

Chart Showing Comparative Activation of Different Receptors by GLP-1 Drugs Involved

12 replies7 peopleOct 26, 2025☆ Follow
Summary

Are published charts of GLP-1 receptor affinities for semaglutide, tirzepatide, retatrutide and similar drugs accurate and useful for understanding real-world effects?

The thread examines one widely shared chart of in-vitro binding values and confirms the numbers match several papers except for survodutide. Participants note the data come from cell assays on human receptors, not human dosing studies, and that tirzepatide is given at higher doses than semaglutide so raw Ki numbers overstate practical differences. Some users suggest the weaker GLP-1 affinity of retatrutide might explain stalls when switching from tirzepatide and propose low-dose semaglutide stacking, while others question whether the chart was generated by AI or taken directly from a review.

What this discussion establishesWhere people disagree

Whether the chart originated from a peer-reviewed figure or was assembled by ChatGPT, and whether other published charts that reverse tirzepatide GLP/GIP values are more plausible.

Still open

How well the in-vitro numbers predict human outcomes or stall-breaking strategies when drugs are combined or switched.

Nothing here is advice.

12 replies · 7 people
CopperLedger37archiveopening postOct 26, 2025

I saw a chart that keeps circulating with claimed potencies for several weight-loss drugs in people. I thought the numbers looked off, yet they lined up with published papers when I checked. The drugs shown are semaglutide, tirzepatide, retatrutide, mazdutide, and survodutide. There are important limits to how the numbers should be used, but I don't know the field well enough to spell those limits out clearly. I'm posting the image plus a PDF that has the clickable links to the original papers.

NorthAnchor41archiveOct 26, 2025

Appreciate you getting everything sorted out here.

SharpAnchor92archiveOct 26, 2025

Appreciate the point. It looks like a key idea when trying to get past a plateau and explains why it's smart to steer clear of oversimplified notions that piling on more of these substances will always help. Every receptor type ties mainly to one helpful outcome such as quieting hunger cues, delaying stomach emptying, shifting how the body uses fuel, and so on. That means changing or combining a drug like this one probably won't fix a given person's unique plateau in the best way. I could attempt to map out those ties but prefer not to risk getting them wrong without proper thought, plus I'm occupied at the moment riding the rails between those two towns.

CopperFenwick68archiveOct 26, 2025
↳ replying to @CopperLedger37 (opening post)

I wonder if that graph came straight out of research papers or if somebody just pieced it together from reading them. Other graphs I've run into flip the values for those two components in the dual version versus the single one, showing a smaller share for the first component. That version lines up better for me since the dual one sits easier with people overall.

AmberMarble84archiveOct 26, 2025
↳ replying to @CopperFenwick68

Those graphs ignore how people actually react. The data came from lab experiments outside any living body. This leaves everything speculative since trials never used real humans. We can't tell whether the outcomes would match for us.

SharpAnchor92archiveOct 26, 2025
↳ replying to @CopperFenwick68

The graph marks stronger connections with smaller figures. I wonder whether this lines up with the point you made.

CopperLedger37archiveOct 26, 2025
↳ replying to @CopperFenwick68

I previously came across that diagram but set aside any thought of its reliability after searching online. The image showed up in various spots yet lacked ties to the academic references I usually trust. So I had an AI generate a fresh version instead. Checking sources against each entry in the new version confirmed all but one medication where the data didn't line up. When I went back to the original dark-themed image its values matched the AI version everywhere except that one spot and the figures for the mismatched item now agreed with what I had located. That leaves me viewing the dark image as reliable. Higher values there signal lower strength at triggering a receptor. Does the medication really activate GLP-1 far more effectively? It does act more potently yet the diagram inflates the actual outcome in people since the other option gets used at larger amounts. Could some formula combine duration in the system peak amounts and binding measures to weigh relative strengths across these compounds? I have no idea how to run the numbers or whether any such equation even works.

CopperLedger37archiveOct 26, 2025
↳ replying to @AmberMarble84

Experiments happened in lab dishes with receptors of the GLP-1 type taken from humans.

KeenLantern39archiveOct 26, 2025

It appears plenty of folks notice their results stalling or even sliding backward after moving across to this newer option from the prior one. Maybe the lower pull at that one receptor site explains the difference. Adding a modest amount of yet another compound would logically fill the gap while hitting every route at peak strength. Anyone else see it that way? I ran the graphs and numbers past a couple of language models for review and they went along with the values in broad terms though not the references behind them. Still feels adequate given the murky setting we operate in.

CopperLedger37archiveOct 26, 2025
↳ replying to @CopperLedger37 (opening post)

I messed up the connection to that semaglutide reference. It reached the identifier page without hitting an open version. So I went back and corrected the whole thing. Attached is the binding comparison file. The study is now linked properly.

CopperLedger37archiveOct 27, 2025

Your chart probably came from an artificial intelligence since the one I received matched those exact values and overall appearance. The figures listed for this medication strike me as inaccurate. No references turned up to support what the chatbot supplied. What turned up instead was a report noting that with full human and mouse plasma present the strength came in at 1.0 and 1.6 nanomolar for the human GLP-1 receptor along with 8.3 and 16 nanomolar for the human glucagon receptor.

ClearWillow59archiveOct 27, 2025

I came across a diagram posted on that forum, can't trace its beginning, and folks spotted inaccuracies in it. Just to note, I sketched some lines showing possible endpoints if the experiments lasted the full period like the other trial did. That one's figures didn't appear quite as strong when compared to the alternatives in the picture.

CopperLedger37archiveOct 27, 2025
↳ replying to @ClearWillow59

This diagram comes from the second illustration inside a study those researchers released back in twenty twenty five. Their work looks at fresh strategies that rely on medicines to address weight problems and it appeared inside the yearly journal on drug actions plus toxins with volume sixty five covering pages one hundred sixty nine through one hundred eighty nine.

Add your experience

If you have tried it, this topic is still open. Sign in to reply — it takes a minute.

Chart Showing Comparative Activation of Different Receptors by GLP-1 Drugs Involved · ZyraTrack Community