I found some content. And I hope it can help you.
The burning sensation when injecting peptide products can be caused by several things. First, certain peptide products can cause an inflammatory response in local tissues during injection, and this inflammatory response may lead to a burning sensation. For example, after an exosome cosmetic injection, a patient experienced moderate pain and a burning sensation that persisted even after the needle was removed.
Second, the use of organic solvents may also be a cause of burning sensations. When organic solvents are rapidly released into the tissues, they may irritate the nerve endings, which can cause a burning sensation. This is more common in long-acting drug delivery formulations, which require injection to achieve rapid drug release.
In addition, activation of the TRPV1 pathway, a heat-sensitive receptor that activates sensory nerve endings and causes burning and itching sensations, may also be an important mechanism for causing burning sensations. When peptide products are injected into the subcutaneous tissue, they may directly or indirectly activate TRPV1, which can cause burning sensations.
In summary, the burning sensation when injecting peptide products may be due to a combination of local inflammatory reactions, the use of organic solvents, and the activation of the TRPV1 pathway.
The specific mechanisms by which peptides induce localized inflammatory responses involve the following:
1.Immunomodulation: Peptides work by regulating cytokines and signaling pathways in the immune system. For example, the antimicrobial peptide LL37 modulates the immune response and influences the onset and progression of skin diseases. In addition, host defense peptides also show immunomodulatory functions, including anti-inflammation and cell chemotaxis.
2.Inhibition of Inflammation-Related Factors: Certain peptide products are able to directly inhibit key factors associated with inflammation. For example, blue copper peptides can inhibit inflammatory responses by decreasing levels of acute inflammatory cytokines.
3.Regulation of Nuclear Transcription Factors: Peptides may also affect the inflammatory response by regulating the expression of nuclear transcription factor κb (NF-κb), an important regulator of inflammation and immune response, whose increased activity often leads to an increased inflammatory response.
4.Promoting angiogenesis and repairing damage: Some peptides have the ability to promote angiogenesis and repair damage, which also helps to reduce the inflammatory state. For example, host defense peptides not only have anti-inflammatory activity, but also promote angiogenesis and repair of damage.
5.Interference with signaling pathways: Peptides may exert anti-inflammatory effects by interfering with signaling pathways associated with the expression of inflammatory cytokines. For example, anti-inflammatory peptides may interfere with signal transduction involved in the expression of inflammatory cytokines.
The TRPV1 pathway plays an important role in the burning sensation induced by peptide products, and its activation mechanism involves multiple factors and signaling pathways.
TRPV1 is a heat-activated cation channel that can be activated by substances such as capsaicin, which triggers burning and pain sensations. Capsaicin is a specific agonist of TRPV1, and when it binds to TRPV1, it causes the channel to open, allowing calcium ions to enter the neuron, which in turn triggers the burning and pain sensations.
In addition, TRPV1 activation is modulated by inflammatory factors. For example, upregulation of COX2 enhances TRPV1 sensitization, which increases TRPV1 activation over a short period of time (approximately 30 minutes). This feed-forward sensitization mechanism may play a role in chronic pain and inflammatory diseases.
I've done some preliminary searching and reading about the causes of Post Injection-site Pain (PIP).
Causes of PIP vary by medication type ie steroids vs peptides vs others.
With peptides the likely cause appears to be a small variation of the med's ph from our body's ph.
The medication ph is usually chemically adjusted during the manufacturing process to normalize it - "buffering" so called.
Not buffering the meds, or not buffering accurately, yields a "burning" sensation at the time of injection.
This should diminish rapidly as the injected solution spreads and is diluted in our bodies.
While not desireable, nothing I have yet read suggests that PIP causes serious or lasting harm.
NOTE: this subject deserves more time than I can give it right now.
I'd enjoy hearing from those of you who have more insight, or more time to research it.
Dennis