[Discussion] can we stop arguing about half-life until somebody posts a number
Slightly embarrassed to be asking this, but: can we stop arguing about half-life until somebody posts a number.
Asked a question here that I thought was stupid and got three papers back. Best thread I have been in on this site.
The GIP question, which is the most interesting unsettled thing in this field.
Dual agonism at GIP and GLP-1 receptors produces clinical results that are robust and well replicated. What is not settled is the mechanism by which the GIP arm contributes — there is a genuine scientific argument about agonism versus antagonism at that receptor, with reasonable people and real data on both sides.
It is worth sitting with that. The clinical effect is not in doubt; the explanation is. That is an ordinary state of affairs in pharmacology and it is a good corrective to the confident mechanistic stories that circulate here.
Why mechanism talk keeps misleading people, including me.
A mechanism tells you a direction. It does not tell you a magnitude, a timescale, or whether the pathway is operative at the exposures involved. "Receptor X is expressed in tissue Y" is a fact; "therefore effect Z in a person" is a hypothesis with several missing steps.
The corrective is boring and it works: ask whether the evidence is preclinical or human, ask what exposure was used, and read the limitations section before the abstract. Most of the confidently wrong posts on this board — several of them mine — skipped all three.
Ask me anything specific. Anything general I will probably get wrong.
best — the order this archive was captured in
GLP-1 receptor agonism acts both peripherally — insulin secretion in a glucose-dependent way, slowed gastric emptying — and centrally, on appetite regulation. The central component is the better explanation for sustained intake reduction.
GLP-1 receptor agonism acts both peripherally — insulin secretion in a glucose-dependent way, slowed gastric emptying — and centrally, on appetite reg
Disagreeing with this specific inference — that is a preclinical result being read as human pharmacology.
Small fix — it slows gastric emptying, it does not halt it, and the distinction matters for the mechanism you are proposing.
GIP is the arm people argue about because the biology is genuinely unsettled
The incretin effect is the observation that oral glucose provokes a larger insulin response than intravenous glucose at matched glycaemia, and the difference is mediated by gut hormones. That is the foundation the whole class sits on.
Speculation is welcome here if it is labelled. This one has been relabelled rather than removed.
Do you have the paper, or a summary of it?
Do you have the paper, or a summary of it?
annika_fonseca is right that mechanism gives direction and not magnitude. Worth pinning.
mechanism explains a direction, not a magnitude
Does the effect persist with continued dosing or does tolerance develop?
That study was in a rodent model. Worth stating, since the thread has been reading it as human data.
GIP receptor biology is genuinely unsettled — there is a live argument about agonism versus antagonism at the receptor — and the clinical results are robust regardless, which is an uncomfortable and interesting position.
What was the exposure in that experiment relative to therapeutic?
half-life is why these are weekly and not daily
receptor distribution is why the side effects are where they are
read the discussion section, that is where the honesty lives
dose response is not linear and nobody should assume it is
dose response is not linear and nobody should assume it is
Adding the caveat the paper itself makes in its limitations section, which is stronger than anything in this thread.
incretin effect first, then everything else in this board makes sense
incretin effect first, then everything else in this board makes sense
Agreed — and it is why the central and peripheral stories are complementary rather than rival.
- 1GIP receptor biology is genuinely unsettled — there is a live argument about…7 comments in this branch · started by u/employer_carveout