Key Growth Factors in Platelet-Rich Plasma

I have mentioned platelet-rich plasma (PRP) in a dozen or so posts on this blog over the past three years. The positive effect of PRP on hair growth is somewhat controversial. However, there is no controversy when it comes to the fact that PRP contains numerous concentrated growth factors (GFs). And many of these growth factors are known to at least modestly benefit hair thickness as well as hair quantity.

PRP Growth Factors
Platelet-Rich Plasma (PRP) Growth Factors.

In the past I have briefly discussed some of the key growth factors that are highly concentrated in PRP. I think it is worth having a separate post here that discusses all of them in a bit more detail. There is a good chance that I am still missing things, so any corrections and suggestions are welcome via the comments.

It should be noted that even many non-PRP related hair loss products target one or more of the below listed growth factors in order to stimulate hair growth. There is a good chance that both PRP as well as hair loss products that contain some of the below growth factors make existing hair stronger. However, it is unlikely that such products ever bring back hair that has been lost for a long time.

Growth Factors in Platelet-Rich Plasma

The key growth factors in PRP treatment that are supposedly beneficial to hair growth are:

  • Insulin-Like Growth Factor 1 (IGF-1).
  • Fibroblast Growth Factor (FGF).
  • Platelet-Derived Growth Factor (PDGF).
  • Vascular Endothelial Growth Factor (VEGF).
  • Epidermal Growth Factor (EGF).
  • Transforming Growth Factor Beta (TGF-β).
  • Nerve Growth Factor (NGF).


I start with the growth hormone insulin-like growth factor 1 (IGF-1) because I have already covered it a few times before.

  • Promotion of IGF-1 expression is one of the main considerations behind Shiseido’s bestselling adenosine based products.
  • US-based Follicept was targeting IGF-1 delivery in its hair loss product, prior to the company’s demise.
  • Adipose-derived stem cells (ADSCs — an exciting recent development in the hair loss world) are rich in various growth factors, including IGF-1.
  • Last year, an important and widely publicized study found that topical application of oleuropein (derived from the leaves of olive drupes) induces hair growth in mice. According to the study findings, oleuropein-treated mouse skin showed substantial upregulation of IGF-1.


I list fibroblast growth factor (FGF) next because I have also covered it many times on this blog before. There are 22 types of FGFs numbered FGF-1 through FGF-22. A significant number of these influence hair growth. I may write an entire detailed post on FGFs at some point in the future. I have covered some of the key ones on this blog before, in particular FGF-5, which discourages hair growth and has to be inhibited. Australian company Cellmid’s Evolis line of products claims to inhibit FGF-5.

Note that PRP does not inhibit growth factors. So it is more relevant for the purposes of this post to discuss some of the FGFs that promote hair growth. It seems like the main ones are FGF-1, FGF-2, FGF-7, FGF-9 and FGF-10. Evidence for three of those (FGF-1, FGF-2 and FGF-10) and their positive effects on hair is found in an important 2014 study from China. Fibroblast growth factors stimulate hair growth through β-Catenin and Shh expression.

Note that “hair cell regeneration” or variations of that term are mentioned a number of times in this study, even if in mice. PRP is said to increase FGF-2 concentration levels. Interestingly, when I interviewed Dr. Malcolm Xing last year, he mentioned that FGF-2 is the preferred growth factor used at this clinic for his work purposes.

FGF-9 has become an especially important growth factor in large part due to the work of the renowned Dr. George Cotsarelis, who holds a patent titled “Fibroblast growth factor-9 promotes hair follicle regeneration after wounding“. Dr. Cotsarelis is also a co-author of a 2013 paper that concludes: “The importance of FGF-9 in hair follicle regeneration suggests that it could be used therapeutically in humans“.

Finally, FGF-7 (also called keratinocyte growth factor, or KGF) is required for hair growth. The well known researcher Dr. Elaine Fuchs co-authored an important study on FGF-7, hair development and wound healing all the way back in 1995. Moreover, Histogen’s Hair Stimulating Complex product is focusing on KGF as one of the key growth factors to be injected in human scalps.


Platelet-derived growth factor (PDGF) is a key growth factor involved in blood vessel formation. A 2006 study from Japan found that “PDGF isoforms induce and maintain anagen phase of murine hair follicles“. Adipose-derived stem cells (ADSCs) are rich in various growth factors, including PDGF, and are increasingly utilized in the hair loss world.


Besides hair growth, vascular endothelial growth factor (VEGF) is also involved in blood vessel formation. A 2001 study concluded that “normal hair growth and size are dependent on VEGF-induced perifollicular angiogenesis”. Note that Shiseido’s adenosine based shampoo also promotes the expression of VEGF. The previously discussed adipose-derived stem cells are also rich in various growth factors including VEGF.

Also, one of the ways in which Minoxidil works to grow hair is via the upregulation of VEGF. Moreover, Histogen’s Hair Stimulating Complex product is focusing on VEGF as one of the key growth factors to be injected in human scalps.

A number of studies have examined natural and synthetic products that increase VEGF and their impact on scalp hair. For example, in 2018, Japanese researchers found that water-soluble chicken egg yolk peptides stimulate hair growth through induction of VEGF production.


Epidermal growth factor (EGF) promotes cell growth, proliferation and differentiation. A 2003 study from Hong Kong concluded that EGF functions as a biological switch that is “turned on and off in hair follicles at the beginning and end of the anagen phase of the hair cycle“.


Transforming growth factor beta (TGF-β) is a cytokine protein growth factor. From the brief research I did, it seems like TGF-β actually adversely impacts hair growth! e.g., see here, here and here. So I am not sure if this growth factor in PRP benefits hair.


There seem to be mixed opinions on the impact of nerve growth factor (NGF) on the hair cycle in any significant manner. A 2006 study suggests both anagen-promoting and catagen-promoting effects of NGF on the hair cycle. Another study, also from 2006, seems to also find different effects of NGF on the hair cycle.

65 thoughts on “Key Growth Factors in Platelet-Rich Plasma”

  1. They have been doing PRP for some time now. It’s quite expensive and very little if any evidence exists for it actually giving people regrowth. I think people would be much better off saving up for hair transplant or saving money for a more effective treatment in the future.

    If anyone got really significant regrowth from this we would have seen 1000 pictures already.

    1. Doesnt that require it to actually work? If anyone sits on secret evidence of great results one would think they come forward by now?

      The lack of proven results rather prove that autoimmune system is not noteworthy involved in mpb. Yeah i have no proof for that but you dont have proof for your conclusion as well.

  2. Very interesting stuff admin. Never realized all the growth factors involved in prp. Wonder how many folks who use those products get any benefits? Maybe topical injections of growth factors would be better rather than the products?

  3. Can sheisidos adenosine actually be bought any more. All im seeing is adenogen. Is that basically the same product? I live in the usa and want to try. Any ideas on how to purchase?

  4. Are there any Doctors that offer PRP that can show any results?

    There’s one here in NYC (Prasad) that offers PRP for $5,000 (half the cost of a good transplant!) and he uses crazy scammy sounding selling points that it’s ‘the cure for baldness’ and ‘works 100% of the time.’ To even see his photos you need to pay $1000 for a consultation.

    He also owns all these SEO clickbait web addresses like and 5 or 6 others all with the same info on them. Another sign of a scam. Why would you need so many websites?

    And he does a lot of YouTube videos with the same scam, just repeats the same info in a different order in new videos with new titles. He posts those all over transplant/plastic surgery forums advising people to first drop 5k on HIM before doing a transplant. Suspicious.

    The photos on his sites also look fishy. Flash vs No Flash, different positions, lighting, hair lengths, etc.

    No one on the internet has any experience with him despite him having ‘thousands of clients.’ Not one wants to even give a good review? Hmmmm.

  5. In any discussion about PRP and associated growth factors, I think it is important to clarify the potential expected benefit. As admin points out: “it is highly unlikely that they ever bring back hair that has been lost for a long time”. This is an accurate statement and I don’t know of any legitimate knowledgeable hair loss professional that would claim otherwise. For example, see this link for a great description: But because it does not grow hair on a bald scalp does not mean that PRP (when used with Acell or BioD Restore) is not beneficial. In my experience, it is a maintenance tool that shows just enough thickening to let you know that it does in fact work. So the value is not so much in taking you forward, but in keeping you from going backward. Also in my experience, it has to be done at least once a year at a cost of $2,500 from a quality professional. The link above is not from my doctor but I provide it because I think it is the best description I have seen of what is actually happening and the expected timeline. It is very consistent with my experience. I just had my third treatment, this time with BioD Restore, and will keep you posted.

  6. Scheduled for PRP in 5 days!
    Pretty excited to finally try out a promising treatment.

    Just hoping it can give my hair a boost until a better treatment comes alive in 2017-2020

    1. Good find, even though I am skeptical about this product being able to do much beyond improving existing scalp hair quality. They have replied to me on Twitter in the past and seem interesting.

    2. thank you very much hopefullybefore2020. Just hope that could lead to something…
      Every time I heard about PRP Just think we deserve something better than PRP ! A lot of studies are so skeptical about that. And when it works, It seams a bit better than Minox !! We are in 2016 Guys !!!

    1. Stanford University or Sanford Burnham?

      Regarding the latter, Dr. Terskikh mentioned on Twitter that they need funding.

  7. Just saw that Samumed is going to release their phase 2b results in spring 2017 conference and that their next step is large scale phase 3. They also mentioned to have fda approval in two years.

    1. Thanks for the update Mjones. There’s some interesting stuff posted in that article.

      Samumed definitely has something cooking for hairloss. I’m excited to hear more in the spring. Hopefully their phase 2 results are even better than before. Its really good news that they are moving onto a phase 3.


  8. I had PRP 2 months after my hair transplant to boost the healing time. At month 4 I ended up where I would have ended up by month 6; the donor area had recovered and the new hair was becoming visible. I had the spare money and did not want to look like Frankenstein for a day longer than I had to. But the surgeon was also very clear that it would not “regenerate” any lost hair. Sadly he was right about that too.

    1. If something does come out, be it the Replicel stem cell method or the JAK inhibitors, it will reverse ALL loss. You have the same number of stem cells you had when you had a full head of hair. You are not and never will be beyond repair. In the meantime, work on getting seriously fit and lean so when the cure comes out you will have young hair on a young body.

  9. @rancidmango I’m with you, it’s great that we have all these “new treatments ” coming out in the so called “next few years”
    Trouble is some of us can’t wait

    1. ya, the “next few years” is more than 10% of my current lifetime. I think I’ve already passed peak rigidity…god I’m old…

        1. You are gonna make it, be positive and grateful for all good things you have (some people cannot even breathe by their own)

    1. Why can’t they just do a parallel trial for AGA along with AA? It’s so stupid. It’s going to be the same drug topically just get 100 aga people and apply it to their scalp to see if it works or not. Why do we have to wait 10 freaking years for this. Soooo annoying. This is why I really hope samumed works very well. They are pushing fast through trials and providing us with updates constantly.

        1. Nai Gianni. Etsi pws to blepw mono aftoi proxorane grigora. An ksekinisoune phase 3 sintoma tote tha eimai sigouros oti tha vgei se 2 xronia.
          Meneis ellada file?

  10. Bored about Alopecia Areata !! Now we know that JAKs work on this kind of alopecia, why doesnt Dr King just focus on Androgenic alopecia ??
    If they are all septics about topical tofacitinib for mpb why they dont just try with injection Under the scalp? Now tofacitinib is a bit cheaper with the generic form I would like to try on my own but wich content use ? Which vehicule ?
    Anyone got information about the setepiprant trial currently in study ?

  11. In next 50, maybe never
    JAK inhibitors- they did not start trials how can it may be hard
    WHY dear christiano and mister king . Name with small letters.

    1. Jere there are many companies working on mpb. My assumption is if they are focusing on AA first then most likely jak won’t work as well for mpb. If it did then you bet your ass they would rush that to market to make billions . At least that what I believe. SM seems to be rushing trials for that exact purpose even if it only gives us 10 to 20% growth.

  12. @Admin not sure if this is just me but on the home page the counter under the title for this thread is stuck on ‘5 comments’ – just a heads up

    1. Hi Jay yes I know and thanks for letting me know. I was downloading various plugins to try to improve the caching mechanism of this blog and optimize it to make it load faster. Unfortunately, several of the plugins might have clashed with each other.

      Can you let me know if you refresh the blog and see the total comment number update? I removed all the plugins yesterday and hopefully this should resolve the issue (at least it seems to have done on my current browser for now).

  13. sorry for bothering again but I can only see recent comments when I post a comment myself… there is some kind of problem with the forum :/

  14. It looks like there is an Australian company selling FGF (FGF5) related products in Australia and the US.

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