🍪 The GLP Lounge uses cookies to improve your experience, analyze traffic, and personalize content. By continuing to use this site, you agree to our Cookie Policy.
Evidence-based GLP-1 & peptide discussion since 2023
ForumsPharmacology & MechanismsHas anyone dealt with my pharmacist tried to explain the mechanism and my eyes glazed over?

Has anyone dealt with my pharmacist tried to explain the mechanism and my eyes glazed over?

labquiet_amy Thu, Mar 21, 2024 at 3:14 PM 34 replies 2,580 viewsPage 1 of 7
This thread is more than 26 months old. Information may be outdated. Consider searching for more recent discussions.
labquiet_amy
Senior Member
1,234
6,789
Mar 2024
Cambridge, MA
Mar 21, 2024 at 3:14 PM#1

Read the primary source rather than the write-up and the two do not agree, so here is what is actually in it.

The mechanism is more central than most summaries suggest. Receptor agonism in the arcuate nucleus activates POMC neurons and inhibits AgRP/NPY signalling, and the downstream MC4R pathway is the same one disrupted in monogenic obesity — convergent genetic evidence that the target is the right one. Peripherally there is glucose-dependent insulin secretion, glucagon suppression and delayed gastric emptying, but the gastric component largely adapts over months while the central effect persists, which is why the durable effect is appetite rather than fullness.

Where I think it is weakest: the subgroup findings are the part I trust least — with enough subgroups something is always significant, and these were not all pre-registered.

The bit I cannot resolve on my own is which effects tachyphylax and which persist, because the answer explains why tolerability improves while the appetite effect keeps working. I would rather have one careful answer than five confident ones.

Note on sourcing:
Figures above are from the primary publication rather than the press summary. If a number here disagrees with one you have, post yours and we will work out which of us is reading a secondary source.
43 13TrialNerd_Beth, HPLC_Greg, LibrarianMeg and 40 others
Reply Quote Save Share Report
Dr.ObesityMed
VIP Member
3,456
19,234
Nov 2023
Denver, CO
Online
Mar 21, 2024 at 3:19 PM#2
labquiet_amy said:
The mechanism is more central than most summaries suggest.

Amycretin (AMY/GLP-1 dual agonist) emerging data relevant to the pharmacology: Phase 1 showed -13.1% body weight at only 12 weeks, the fastest trajectory ever seen for an anti-obesity agent[1].

Amylin receptor agonism enhances satiety signaling through the area postrema and reduces glucagon secretion. Combined with GLP-1R agonism, this dual mechanism may produce even greater efficacy than current agents.

Early-stage data — interpret with caution. But the trajectory is extraordinary.

References:
[1] Novo Nordisk investor presentation, September 2023.
42 12PharmacoVig_BOS, SurmountFan_IN, PeptideChemSF and 39 others
Reply Quote Save Share Report
TrialNerd_Beth
Senior Member
2,345
11,234
Jan 2024
Bethesda, MD
Mar 21, 2024 at 3:24 PM#3
labquiet_amy said:
The mechanism is more central than most summaries suggest.

Pushing back on labquiet_amy here. The pharmacokinetics explain nearly every practical question asked here. Albumin binding above 99% slows clearance enough to make weekly dosing possible; a terminal half-life near a week means four to five weeks to steady state and therefore a four-week titration interval; subcutaneous bioavailability around 89% means injection site barely matters. Those three facts answer most timing questions before they are asked.

41 11TomTeleRx, DoseLogDan, SleepFixSam and 38 others
Reply Quote Save Share Report

PeptideMeter — Independent Peptide Analytics

Community-driven peptide testing and vendor rating platform. Transparent results. Unbiased analysis. Trusted by thousands.

View Results
TinaHashiRN
Member
345
1,567
Sep 2024
Raleigh, NC
Mar 21, 2024 at 3:29 PM#4
TrialNerd_Beth said:
The pharmacokinetics explain nearly every practical question asked here.

Semaglutide structural biology relevant to the pharmacology: semaglutide is a 31-amino acid peptide with 94% homology to native GLP-1(7-36). Three key modifications enable its pharmacokinetic profile:

  1. Aib8 substitution: DPP-4 resistance (prevents enzymatic degradation)
  2. Arg34 substitution: improved chemical stability
  3. C18 fatty diacid at Lys26: albumin binding → long half-life

These three modifications transform a peptide with a 2-minute half-life (native GLP-1) into one with a 168-hour half-life (semaglutide). A masterclass in peptide engineering.

40 10Admin, Dr.Martinez, mike_mod and 37 others
Reply Quote Save Share Report
jim_asheville
Member
289
1,234
Aug 2024
Asheville, NC
Mar 21, 2024 at 3:55 PM#5
Dr.ObesityMed said:
Amycretin (AMY/GLP-1 dual agonist) emerging data relevant to the pharmacology: Phase 1 showed -13.1% body weight at only 12 weeks, the fastest…

This matches mine closely enough to be worth saying so out loud. Posting only so the count is not one.

39 9LarryQC_SD, wanda_boise, NurseAsh_DET and 36 others
Reply Quote Save Share Report
1237

Similar Threads

GLP-1R desensitization — β-arrestin-mediated internalization18 replies
Biased agonism at GLP-1R — Gs vs β-arrestin signaling balance13 replies
Semaglutide albumin binding and the C-18 fatty acid linker17 replies
GIP receptor pharmacology — why GIP agonism enhances GLP-113 replies
Glucagon receptor signaling — hepatic glycogenolysis and lipolysis16 replies
ForumsNewTrendingMembersAccount

Log In

Forgot password?
No account? Register