Stuff like grape seed extract is supposed to spur collagen synthesis and from what I can tell, it does. Skin texture gets subtely smoother when on it.
All in all, stretching and maintaining elasticity has been my biggest hurtle when bulking up. Forced stretches, IMO, are the only thing that will reliably lengthen tendons and induced micro tears that spur collagen repair. Things like Celadrin my help facilitate this but getting older is getting older..it sucks, lol. I noticed signifcant tendon repair from IGF r3...but I never maintain my stretching routine so it was lost.
I used to be able to jump into the splits and jump kick the top of a door frame 15 years ago, now I can hardly touch my toes.
There's a few studies on horses that seem to support IGF-1 induced tendon repair. A few anecdotal reports confirm this in humans as well.
J Orthop Res. 2002 Sep;20(5):910-9. Related Articles, Links
Insulin-like growth factor-I improves cellular and molecular aspects of healing in a collagenase-induced model of flexor tendinitis.
Dahlgren LA, van der Meulen MC, Bertram JE, Starrak GS, Nixon AJ.
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Veterinary Medical Center, Ithaca, NY 14853, USA.
Flexor tendinitis is a common and debilitating injury of elite and recreational athletes. Healing may be improved through intratendinous injection of insulin-like growth factor-I (IGF-I), which has been shown in vitro to stimulate mitogenesis and enhance tendon matrix production. This study investigated the effects of intratendinous injection of IGF-I on tendon healing in an equine model of flexor tendinitis. Collagenase-induced lesions were created in the tensile region of theflexor digitorum superficialis tendon of both forelimbs of eight horses. Treated tendons were injected with 2 microg rhlGF-I intralesionally every other day for 10 injections, while controls received 0.9% NaCl. Tendon fiber deposition and organization were evaluated serially using ultrasonography throughout the 8 week trial period. Following euthanasia, the tendons were harvested and DNA, hydroxyproline, and glycosaminoglycan content determined, mechanical strength and stiffness evaluated, gene expression and spatial arrangement of collagen types I and III assessed by northern blot and in situ hybridization, and tendon fiber architecture assessed by polarized light microscopy. Local soft tissue swelling was reduced in the IGF-I treated limbs. Similarly, lesion size in IGF-I treated tendons was smaller 3 and 4 weeks after initiation of treatment. Cell proliferation and collagen content of the IGF-I treated tendons were increased compared to controls. Mechanically, IGF-I treated tendons showed a trend toward increased stiffness compared to saline treated controls. Considered together with the decreased soft tissue swelling and improved sonographic healing, these data support the potential use of intralesional IGF-I for treatment of debilitating tendon injuries.
PMID: 12382953 [PubMed - indexed for MEDLINE]
Am J Vet Res. 1997 Jan;58(1):103-9. Related Articles, Links
Biochemical and site-specific effects of insulin-like growth factor I on intrinsic tenocyte activity in equine flexor tendons.
Murphy DJ, Nixon AJ.
Comparative Orthopaedics Laboratory, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
OBJECTIVE: To examine the site-specific and dose-dependent effects of insulin-like growth factor I (IGF-I) on normal equine tendon in vitro. SAMPLES: Superficial digital flexor tendon explants derived from a euthanatized 3-year-old horse. PROCEDURE: Explants in culture were treated with 0, 100, 250, or 500 ng of IGF-I/ml for 14 days with an end-stage radiolabel of 20 microCi of [3H]proline/ml or 5 microCi of [3H]thymidine/ml. The tendon tissues were then analyzed biochemically for hydroxyproline content by reverse-phase high-performance liquid chromatography, DNA content by fluorometry, and glycosaminoglycan content by the dimethylmethylene blue dye-binding assay. In addition, morphologic analysis of the explants comprised histologic examination, autoradiography, and immunohistochemistry. RESULTS: Hydroxyproline content was significantly increased in explants treated with 100 and 250 ng of IGF-I/ml. Additionally, the collagen synthetic rate, measured by incorporation of [3H]proline into hydroxyproline, was significantly increased for all treatment groups. On the basis of autoradiograms, fibroblast proliferation and collagen synthesis were predominantly confined to the endcap and adjacent endotenon of the explants. Enhanced immunoreactivity for type-I collagen, compared with type-III collagen, was evident in the treated explants, an observation supported by positive staining for type-I collagen with picrosirius red. Histologically, treated explants contained greater numbers of larger and more metabolically active fibroblasts, compared with untreated controls. CONCLUSION: IGF-I enhances collagen synthesis in normal equine flexor tendon in a dose-dependent manner. IGF-I also exerts its primary effect on cell proliferation and collagen synthesis in the epitenon and adjacent endotenon and accompanying perivascular connective tissues, consistent with enhancement of intrinsic tendon metabolism. CLINICAL RELEVANCE: IGF-I may have a potential role in the treatment of tendinitis in horses.
PMID: 8989505 [PubMed - indexed for MEDLINE]