Management of hair loss
The management of hair loss, also known as alopecia or baldness, may include medications, surgery, and fashion accessories.[medical citation needed]
- 1 Medication
- 2 Hair transplantation
- 3 Radiation induced hair loss
- 4 Cosmeses
- 5 Alternative medicine
- 6 Mechanism
- 7 Research
- 8 References
- 9 External links
Treatments for the various forms of hair loss have on moderate success. Three medications have evidence to support their use in male pattern hair loss: finasteride, dutasteride and minoxidil. They typically work better to prevent further hair loss than to regrow lost hair.
They may be used together when hair loss is progressive or further regrowth is desired after 12 months. Other medications include ketoconazole, and in female androgenic alopecia spironolactone and flutamide. Combinations of finasteride, minoxidil and ketoconazole are more effective than individual use.
Finasteride is used to treat male pattern hair loss. Treatment provides about 30% improvement in hair loss after six months of treatment, and effectiveness only persists as long as the drug is taken. There is no good evidence for its use in women.
Minoxidil, applied topically, is widely used for the treatment of hair loss. It is effective in helping promote hair growth in both males and females with androgenic alopecia. About 40% of men experience hair regrowth after 3–6 months. It is the only topical product that is FDA approved for androgenic hair loss.
There is tenative support for spironolactone is women. Due to its feminizing side effects and risk of infertility in men it is noto often used in males. It can also cause hypotension, hyperkalemia, and cardiac dysrhythmia. Also, women who are pregnant or trying to become pregnant generally cannot use the medication as it is a teratogen, and can cause ambiguous genitalia in newborns.
Hair transplantation is a surgical technique that moves individual hair follicles from a part of the body called the donor site to bald or balding part of the body known as the recipient site. It is primarily used to treat male pattern baldness. In this condition, grafts containing hair follicles that are genetically resistant to balding are transplanted to bald scalp. It is also used to restore eyelashes, eyebrows, beard hair, chest hair, and pubic hair and to fill in scars caused by accidents or surgery such as face-lifts and previous hair transplants. Hair transplantation differs from skin grafting in that grafts contain almost all of the epidermis and dermis surrounding the hair follicle, and many tiny grafts are transplanted rather than a single strip of skin.
Since hair naturally grows in follicles in groups of 1 to 4 hairs, transplantation takes advantage of these naturally occurring follicular units. This achieves a more natural appearance by matching hair for hair through Follicular unit transplantation (FUT).
Donor hair can be harvested in two different ways. Small grafts of naturally-occurring units of one to four hairs, called follicular units, can be moved to balding areas of the hair restoration. These follicular units are surgically implanted in the scalp in very close proximity to one another and in large numbers. The grafts are obtained in one or both of the two primary methods of surgical extraction, follicular unit transplantation, colloquially referred to as "strip harvesting", or Follicular Unit Extraction (FUE), in which follicles are transplanted individually.
In FUT, a strip of skin containing many follicular units is extracted from the patient and dissected under stereoscopic microscope. The site of the strip removal is stiched closed. Once divided into follicular unit grafts, the surgeon implants each unit is individually inserted into small recipient sites made by incision in the bald scalp. In newer technique, roots are extracted from the donor area and divided into strips for transplantation. The strip, two to three millimeters thick, is isolated and transplanted to the bald scalp. After surgery, a bandage is worn for two days to protect the stiched strip during healing. A small strip scar remains after healing, which can be covered by scalp hair growing over the scar.
Radiation induced hair loss
Radiation induces hair loss through damage to hair follicle stem cell progenitors and alteration of keratin expression. Radiation therapy has been associated with increased mucin production in hair follicles.
Studies have suggested electromagnetic radiation as a therapeutic growth stimulant in alopecia.
Certain hair shampoos and ointments visually thicken existing hair, without affecting the growth cycle. There have also been developments in the fashion industry with wig design. The fashion accessory has also been shown to be a source of psychological support for women undergoing chemotherapy, with cancer survivors in one study describing their wig as a "constant companion". Other studies in women have demonstrated a more mixed psychosocial impact of hairpiece use.
2008 and 2012 reviews found little evidence to support the use of special lights or lasers to treat hair loss. Additionally none are FDA approved for this use. Both laser and lights appear to be safe.
Dietary supplements are not typically recommended. There is only one small trial of saw palmetto which shows tentative benefit in those with mild to moderate androgenetic alopecia. There is no evidence for biotin. Evidence for most other produces is also insufficient. There was no good evidence for gingko, aloe vera, ginseng, bergamot, or hibiscus as of 2011.
Several lines of evidence support the dermal papilla of the hair follicle as the androgenic target for hair loss prevention and reversal. Type 1 and 2 5α reductase enzymes are present at pilosebaceous units in papillae of individual hair follicles. They catalyze formation of the androgens testosterone and DHT, which in turn regulate hair growth. Androgens have different effects at different follicles: they stimulate IGF-1 at facial hair, causing hair regrowth, but stimulate TGF β1, TGF β2, dickkopf1 and IL-6 at the scalp, causing hair follicle miniaturization.
Female androgenic alopecia is characterized by diffuse crown thinning without hairline recession, and like its male counterpart rarely leads to total hair loss. Finasteride and minoxidil are usually first line therapy for its treatment. Other options include topical or systemic spironolactone or flutamide, although they have a high incidence of feminizing side effects and are better tolerated in female androgenic hair loss.
More advanced cases may be resistant or unresponsive to medical therapy, however, and require hair transplantation. Naturally-occurring units of one to four hairs, called follicular units, are excised and moved to areas of hair restoration. These follicular units are surgically implanted in the scalp in close proximity and in large numbers. The grafts are obtained from either Follicular Unit Transplantation (FUT) – colloquially referred to as "strip harvesting" – or Follicular Unit Extraction (FUE). In the former, a strip of skin with follicular units is extracted and dissected into individual follicular unit grafts. The surgeon then implants the grafts into small incisions, called recipient sites. Specialized scalp tattoos can also mimic the appearance of a short buzzed haircut. Androgenic alopecia also occurs in females, and more often presents as diffuse thinning without hairline recession. Like its male counterpart, the condition rarely leads to total hair loss. Treatment options are similar to those for men, although topical or systemic estrogen is used more often.
Bimatoprost and latanoprost
Latanoprost and bimatoprost are specific PGF2a analogues applied topically, and have been found to lengthen eyelashes, darken hair pigmentation and elongate hair. Bimatoprost is available as treatment for eyelash growth. Latanoprost has shown ability to promote scalp hair density and pigmentation, and is theorized to function at the dermal papilla. A study found latanoprost ineffective on eyelashes in a patient with alopecia areata. It has also been found ineffective in treatment of eyebrow hair loss.
Estrogens are indirect anti-androgens, and can be used to treat androgenetic hair loss in females with oral contraceptives. Systemic estrogen increases SHBG, which binds androgens, including testosterone and DHT, in turn reducing their bioavailability. Topical formulations are available in Europe. Hair follicles have estrogen receptors and it is theorized topical compounds act on them directly to promote hair growth and antagonize androgen action. Large clinical studies showing effectiveness are absent. Topical treatment is also usually unavailable in North America.
In December 2012, topical application of IGF-1 in a liposomal vehicle led to thicker and more rapid hair growth in transgenic mice with androgenic alopecia. The study did not show measurable systemic levels or hematopoietic side effects, suggesting potential for use in humans. Low energy radiofrequency irradiation induces IGF-1 in cultured human dermal papilla cells. Adenosine stimulates dermal papillae in vitro to induce IGF-1, along with fibroblast growth factors FGF7, FGF-2 and VEGF. β-catenin transcription increased, which promotes dermal papillae as well. Dietary isoflavones increase IGF production in scalp dermal papillae in transgenic mice. Topical capsaicin also stimulates IGF at hair follicles via release of vanilloid receptor-1, which in turn leads to more CGRP. Ascorbic acid has led to increased IGF expression in vitro.
Stem cell therapy
Although follicles were previously thought gone in areas of complete baldness, they are more likely dormant, as recent studies have shown the scalp contains the stem cells from which the follicles arose. Research on these follicular stem cells may lead to successes in treating baldness through hair multiplication (HM), also known as hair cloning.
One of the groups developing hair multiplication is Aderans Research Institute (ARI), a Japanese owned company in the United States. In 2008, Intercytex announced results of a Phase II trial to clone hair follicles from the back of the neck, multiply them and then reimplant the cells into the scalp. Initial testing showed at least two thirds of male patients regrew hair. The company estimated treatment would take "a number of years to complete" Phase III trials. After failing to achieve success in their trials, the company discontinued its hair multiplication project in 2010, with intention to sell off its assets and research. Aderans Research Institute Inc. (ARI) then acquired technology from Regenerative Medicine Assets Limited (formerly Intercytex Group plc) and is conducting Phase II clinical trials.
Scientists grew the first artificial hair follicles from stem cells in 2010. Researchers in the study predicted that by 2015 people could grow new hair from their own stem cells, and have it surgically implanted at areas of hair loss. The lead investigator said preparations for clinical trials were "already in motion". In their first human clinical trial, Replicel Life Sciences was able to regenerate 20% percent of hair on stem cell treated areas. Replicel is using dermal sheath cup cells instead of dermal papillae cells for multiplication, in distinction to Aderans. They will be conducting Phase II trials at the end of 2012. In early 2012 a research group demonstrated "functional hair regeneration from adult stem cells" in mouse animal models with the potential for "organ replacement regenerative therapies".
A March 26, 2015 study showed treatment using adipose-derived stem cells, had increased the number of hairs, and may be a future treatment for hair loss. Adipose-derived stem cells secrete various growth factors that promote hair growth.
Per a May 2015 review, no successful strategy to generate human hair follicles, for hair regrowth, from adult stem cells has yet been reported.
Curis and Procter & Gamble spent one million on development of a topical hedgehog agonist for hair loss. The agent did not meet safety standards, and the program was stopped in 2007. In 2008 researchers at the University of Bonn announced they have found the genetic basis of two distinct forms of inherited hair loss. They found the gene P2RY5 causes a rare, inherited form of hair loss called hypotrichosis simplex. It is the first receptor in humans known to play a role in hair growth. Researchers found that disruption of the gene SOX21 in mice caused cyclical hair loss. Research has suggested SOX21 as a master regulator of hair shaft cuticle differentiation, with its disruption causing cyclical alopecia in mice models. Deletion of SOX21 dramatically affects hair lipids.
- Levy, Lauren L.; Emer, Jason J. (29 August 2013). "Female pattern alopecia: current perspectives". International Journal of Women's Health 5: 541–56. doi:10.2147/IJWH.S49337. PMID 24039457.
- Banka, N; Bunagan, MJ; Shapiro, J (January 2013). "Pattern hair loss in men: diagnosis and medical treatment". Dermatologic clinics 31 (1): 129–40. doi:10.1016/j.det.2012.08.003. PMID 23159182.
- "Propecia & Rogaine for Treating Male Pattern Baldness". Webmd.com. Retrieved May 19, 2010.
- McElwee, K. J.; Shapiro, J. S. (2012). "Promising therapies for treating and/or preventing androgenic alopecia". Skin therapy letter 17 (6): 1–4. PMID 22735503.
- Khandpur, S.; Suman, M.; Reddy, B. S. (2002). "Comparative efficacy of various treatment regimens for androgenetic alopecia in men". The Journal of dermatology 29 (8): 489–498. PMID 12227482.
- "Propecia label" (PDF).
- Varothai, S; Bergfeld, WF (Jul 2014). "Androgenetic alopecia: an evidence-based treatment update.". American journal of clinical dermatology 15 (3): 217–30. doi:10.1007/s40257-014-0077-5. PMID 24848508.
- Andersson, S. (2001). "Steroidogenic enzymes in skin". European journal of dermatology : EJD 11 (4): 293–295. PMID 11399532.
- Avodart 0.5 mg soft capsules | SPC from the eMC
- Varothai, S; Bergfeld, WF (July 2014). "Androgenetic alopecia: an evidence-based treatment update.". American journal of clinical dermatology 15 (3): 217–30. PMID 24848508.
- van Zuuren, EJ; Fedorowicz, Z; Carter, B; Andriolo, RB; Schoones, J (16 May 2012). "Interventions for female pattern hair loss.". The Cochrane database of systematic reviews 5: CD007628. PMID 22592723.
- "Clinical utility and validity of minoxidil response testing in androgenetic alopecia.". Dermatol Ther 28 (1): 13–6. doi:10.1111/dth.12164. PMID 25112173.
- Buchanan, J. F.; Davis, L. J. (1984). "Drug-induced infertility". Drug intelligence & clinical pharmacy 18 (2): 122–132. PMID 6141923.
- Sinclair, R.; Patel, M.; Dawson, T. L.; Yazdabadi, A.; Yip, L.; Perez, A.; Rufaut, N. W. (2011). "Hair loss in women: Medical and cosmetic approaches to increase scalp hair fullness". British Journal of Dermatology 165: 12–18. doi:10.1111/j.1365-2133.2011.10630.x. PMID 22171680.
- Rathnayake, D.; Sinclair, R. (2010). "Use of spironolactone in dermatology". Skinmed 8 (6): 328–332; quiz 332. PMID 21413648.
- Yazdabadi, A.; Sinclair, R. (2011). "Treatment of female pattern hair loss with the androgen receptor antagonist flutamide". Australasian Journal of Dermatology 52 (2): 132–134. doi:10.1111/j.1440-0960.2010.00735.x. PMID 21605098.
- Rashid, R. M.; Morgan Bicknell, L. T. (2012). "Follicular unit extraction hair transplant automation: Options in overcoming challenges of the latest technology in hair restoration with the goal of avoiding the line scar". Dermatology online journal 18 (9): 12. PMID 23031379.
- Caroli, S.; Pathomvanich, D.; Amonpattana, K.; Kumar, A. (2011). "Current status of hair restoration surgery". International surgery 96 (4): 345–351. PMID 22808618.
- Nanashima, N.; Ito, K.; Ishikawa, T.; Nakano, M.; Nakamura, T. (2012). "Damage of hair follicle stem cells and alteration of keratin expression in external radiation-induced acute alopecia". International Journal of Molecular Medicine 30 (3): 579–584. doi:10.3892/ijmm.2012.1018. PMID 22692500.
- Kamiya, K.; Sasatani, M. (2012). "Effects of radiation exposure on human body". Nihon rinsho. Japanese journal of clinical medicine 70 (3): 367–374. PMID 22514910.
- Takeda, H.; Nakajima, K.; Kaneko, T.; Harada, K.; Matsuzaki, Y.; Sawamura, D. (2011). "Follicular mucinosis associated with radiation therapy". The Journal of Dermatology 38 (11): 1116–1118. doi:10.1111/j.1346-8138.2010.01187.x. PMID 22034994.
- Kalia, S.; Lui, H. (2012). "Utilizing Electromagnetic Radiation for Hair Growth". Dermatologic Clinics 31 (1): 193–200. doi:10.1016/j.det.2012.08.018. PMID 23159188.
- Davis, M. G.; Thomas, J. H.; Van De Velde, S.; Boissy, Y.; Dawson Jr, T. L.; Iveson, R.; Sutton, K. (2011). "A novel cosmetic approach to treat thinning hair". British Journal of Dermatology 165: 24–30. doi:10.1111/j.1365-2133.2011.10633.x. PMID 22171682.
- Zannini, L.; Verderame, F.; Cucchiara, G.; Zinna, B.; Alba, A.; Ferrara, M. (2012). "'My wig has been my journey's companion': Perceived effects of an aesthetic care programme for Italian women suffering from chemotherapy-induced alopecia". European Journal of Cancer Care 21 (5): 650–660. doi:10.1111/j.1365-2354.2012.01337.x. PMID 22339814.
- Inui, S.; Inoue, T.; Itami, S. (2012). "Psychosocial impact of wigs or hairpieces on perceived quality of life level in female patients with alopecia areata". The Journal of Dermatology 40 (3): 225–6. doi:10.1111/1346-8138.12040. PMID 23252418.
- Elisabeth Leamy (May 31, 2012). "Considering a hair tattoo? Pros and cons to consider before you commit". ABC News. Retrieved December 16, 2012.
- Bella Battle (February 11, 2012). "Wish you were hair". The Sun (London). Retrieved December 16, 2012.
- Rogers, NE; Avram, MR (October 2008). "Medical treatments for male and female pattern hair loss.". Journal of the American Academy of Dermatology 59 (4): 547–66; quiz 567–8. PMID 18793935.
- Rangwala, Sophia; Rashid, Rashid M. (Feb 2012). "Alopecia: a review of laser and light therapies". Dermatology Online Journal 18 (2): 3. ISSN 1087-2108. PMID 22398224.
Since then, a number of studies have suggested the use of lasers as an effective way to treat alopecia, particularly androgenetic alopecia and alopecia areata, but there is still a paucity of independent, peer-reviewed blinded clinical trials.
- Avci, Pinar; Gupta, Gaurav K.; Clark, Jason; Wikonkal, Norbert; Hamblin, Michael R. (2014). "Low-Level Laser (Light) Therapy (LLLT) for Treatment of Hair Loss". Lasers in surgery and medicine 46 (2): 144–151. doi:10.1002/lsm.22170. ISSN 0196-8092. PMC 3944668. PMID 23970445.
- Gupta, AK; Daigle, D (April 2014). "The use of low-level light therapy in the treatment of androgenetic alopecia and female pattern hair loss.". The Journal of dermatological treatment 25 (2): 162–3. PMID 23924031.
- Blumeyer, A; Tosti, A; Messenger, A; Reygagne, P; Del Marmol, V; Spuls, PI; Trakatelli, M; Finner, A; Kiesewetter, F; Trüeb, R; Rzany, B; Blume-Peytavi, U; European Dermatology Forum, (EDF) (October 2011). "Evidence-based (S3) guideline for the treatment of androgenetic alopecia in women and in men.". Journal der Deutschen Dermatologischen Gesellschaft = Journal of the German Society of Dermatology : JDDG. 9 Suppl 6: S1–57. PMID 21980982.
- Soni, V. K. (2009). "Androgenic alopecia: A counterproductive outcome of the anabolic effect of androgens". Medical Hypotheses 73 (3): 420–426. doi:10.1016/j.mehy.2009.03.032. PMID 19477078.
- Inui, Shigeki; Itami, Satoshi (2013). "Androgen actions on the human hair follicle: perspectives". Experimental Dermatology 22 (3): 168–171. doi:10.1111/exd.12024. PMID 23016593.
- "Female pattern baldness". MedlinePlus. December 15, 2012. Retrieved December 15, 2012.
- Rose, P. (2011). "The Latest Innovations in Hair Transplantation". Facial Plastic Surgery 27 (4): 366–377. doi:10.1055/s-0031-1283055. PMID 21792780.
- Kovalevsky, G.; Ballagh, S. A.; Stanczyk, F. Z.; Lee, J.; Cooper, J.; Archer, D. F. (2010). "Levonorgestrel effects on serum androgens, sex hormone–binding globulin levels, hair shaft diameter, and sexual function". Fertility and Sterility 93 (6): 1997–2003. doi:10.1016/j.fertnstert.2008.12.095. PMID 19394598.
- Law, S. K. (2010). "Bimatoprost in the treatment of eyelash hypotrichosis". Clinical ophthalmology (Auckland, N.Z.) 4: 349–358. doi:10.2147/opth.s6480. PMC 2861943. PMID 20463804.
- Tosti, A.; Pazzaglia, M.; Voudouris, S.; Tosti, G. (2004). "Hypertrichosis of the eyelashes caused by bimatoprost". Journal of the American Academy of Dermatology 51 (5): S149–S150. doi:10.1016/j.jaad.2004.05.002. PMID 15577756.
- Wand, M. (1997). "Latanoprost and hyperpigmentation of eyelashes". Archives of ophthalmology 115 (9): 1206–1208. doi:10.1001/archopht.1997.01100160376025. PMID 9298071.
- Banaszek, A. (2011). "Company profits from side effects of glaucoma treatment". Canadian Medical Association Journal 183 (14): E1058–E10F1. doi:10.1503/cmaj.109-3919. PMC 3185096. PMID 21876012.
- Blume-Peytavi, U.; Lönnfors, S.; Hillmann, K.; Garcia Bartels, N. (2012). "A randomized double-blind placebo-controlled pilot study to assess the efficacy of a 24-week topical treatment by latanoprost 0.1% on hair growth and pigmentation in healthy volunteers with androgenetic alopecia". Journal of the American Academy of Dermatology 66 (5): 794–800. doi:10.1016/j.jaad.2011.05.026. PMID 21875758.
- Johnstone, M. A.; Albert, D. M. (2002). "Prostaglandin-induced hair growth". Survey of ophthalmology. 47 Suppl 1: S185–S202. PMID 12204716.
- Roseborough, I.; Lee, H.; Chwalek, J.; Stamper, R. L.; Price, V. H. (2009). "Lack of efficacy of topical latanoprost and bimatoprost ophthalmic solutions in promoting eyelash growth in patients with alopecia areata". Journal of the American Academy of Dermatology 60 (4): 705–706. doi:10.1016/j.jaad.2008.08.029. PMID 19293023.
- Ross, E. K.; Bolduc, C.; Lui, H.; Shapiro, J. (2005). "Lack of efficacy of topical latanoprost in the treatment of eyebrow alopecia areata". Journal of the American Academy of Dermatology 53 (6): 1095–1096. doi:10.1016/j.jaad.2005.06.031. PMID 16310083.
- Blumeyer, A.; Tosti, A.; Messenger, A.; Reygagne, P.; Del Marmol, V.; Spuls, P. I.; Trakatelli, M.; Finner, A.; Kiesewetter, F.; Trüeb, R.; Rzany, B.; Blume-Peytavi, U. (2011). "Evidence-based (S3) guideline for the treatment of androgenetic alopecia in women and in men". JDDG: Journal der Deutschen Dermatologischen Gesellschaft 9: S1–57. doi:10.1111/j.1610-0379.2011.07802.x. PMID 21980982.
- Castro, R. F.; Azzalis, L. A.; Feder, D.; Perazzo, F. F.; Pereira, E. C.; Junqueira, V. B. C.; Rocha, K. C.; Machado, C. D. A.; Paschoal, F. C.; Gnann, L. A.; Fonseca, F. L. A. (2012). "Safety and efficacy analysis of liposomal insulin-like growth factor-1 in a fluid gel formulation for hair-loss treatment in a hamster model". Clinical and Experimental Dermatology 37 (8): 909–912. doi:10.1111/j.1365-2230.2012.04441.x. PMID 22924775.
- Yoon, S. Y.; Kim, K. T.; Jo, S. J.; Cho, A. R.; Jeon, S. I.; Choi, H. D.; Kim, K. H.; Park, G. S.; Pack, J. K.; Kwon, O. S.; Park, W. Y. (2011). Najbauer, Joseph, ed. "Induction of Hair Growth by Insulin-Like Growth Factor-1 in 1,763 MHz Radiofrequency-Irradiated Hair Follicle Cells". PLoS ONE 6 (12): e28474. doi:10.1371/journal.pone.0028474. PMC 3229574. PMID 22164296.
- Zhao, J.; Harada, N.; Kurihara, H.; Nakagata, N.; Okajima, K. (2011). "Dietary isoflavone increases insulin-like growth factor-I production, thereby promoting hair growth in mice". The Journal of Nutritional Biochemistry 22 (3): 227–233. doi:10.1016/j.jnutbio.2010.01.008. PMID 20576422.
- Okajima, K.; Harada, N. (2008). "Promotion of insulin-like growth factor-I production by sensory neuron stimulation; molecular mechanism(s) and therapeutic implications". Current medicinal chemistry 15 (29): 3095–3112. doi:10.2174/092986708786848604. PMID 19075656.
- Kwack, M. H.; Shin, S. H.; Kim, S. R.; Im, S. U.; Han, I. S.; Kim, M. K.; Kim, J. C.; Sung, Y. K. (2009). "L-Ascorbic acid 2-phosphate promotes elongation of hair shafts via the secretion of insulin-like growth factor-1 from dermal papilla cells through phosphatidylinositol 3-kinase". British Journal of Dermatology 160 (6): 1157–1162. doi:10.1111/j.1365-2133.2009.09108.x. PMID 19416266.
- Valente Duarte de Sousa, Isabel Cristina; Tosti, Antonella (May 2013). "New investigational drugs for androgenetic alopecia". Expert Opinion on Investigational Drugs 22 (5): 573–589. doi:10.1517/13543784.2013.784743. ISSN 1744-7658. PMID 23550739.
- Garza, L. A.; Yang, C. C.; Zhao, T.; Blatt, H. B.; Lee, M.; He, H.; Stanton, D. C.; Carrasco, L.; Spiegel, J. H.; Tobias, J. W.; Cotsarelis, G. (2011). "Bald scalp in men with androgenetic alopecia retains hair follicle stem cells but lacks CD200-rich and CD34-positive hair follicle progenitor cells". Journal of Clinical Investigation 121 (2): 613–622. doi:10.1172/JCI44478. PMC 3026732. PMID 21206086.
- "Hair Cloning Nears Reality as Baldness Cure". Webmd.com. November 4, 2004. Retrieved August 10, 2006.
- "Big Baldness Breakthrough?". Associated Press. March 15, 2004. Archived from the original on May 25, 2006. Retrieved August 10, 2006.
- "ICX-TRC – Frequently Asked Questions". Intercytex. March 22, 2010. Retrieved May 19, 2010.
- "Intercytex Discontinues its Hair Multiplication Development Operations | Hair Loss Q & A". Regrowhair.com. January 7, 2010. Retrieved May 19, 2010.
- Follicle Neogenesis, Bio Engineered Hair Loss Solution | Aderans Research
- Bates, Claire (December 20, 2010). "Cure for baldness on the horizon as scientists grow world's first hair follicles using stem cells". Daily Mail (London).
- Fukuoka, Hirotaro; Suga, Hirotaka (2015). "Hair Regeneration Treatment Using Adipose-Derived Stem Cell Conditioned Medium: Follow-up With Trichograms". Eplasty 15: e10. ISSN 1937-5719. PMC 4379938. PMID 25834689.
- Balañá, María Eugenia; Charreau, Hernán Eduardo; Leirós, Gustavo José (May 26, 2015). "Epidermal stem cells and skin tissue engineering in hair follicle regeneration". World Journal of Stem Cells 7 (4): 711–727. doi:10.4252/wjsc.v7.i4.711. ISSN 1948-0210. PMC 4444612. PMID 26029343.
- Procter & Gamble (September 19, 2005). "Curis and Procter & Gamble Enter into R&D Agreement for Hair Growth Program". Archived from the original on August 22, 2006. Retrieved August 24, 2006.
- Pasternack, S. M.; Von Kügelgen, I.; Al Aboud, K. A.; Lee, Y. A.; Rüschendorf, F.; Voss, K.; Hillmer, A. M.; Molderings, G. J.; Franz, T.; Ramirez, A.; Nürnberg, P.; Nöthen, M. M.; Betz, R. C. (2008). "G protein–coupled receptor P2Y5 and its ligand LPA are involved in maintenance of human hair growth". Nature Genetics 40 (3): 329–334. doi:10.1038/ng.84. PMID 18297070.
- Shimomura, Y.; Wajid, M.; Ishii, Y.; Shapiro, L.; Petukhova, L.; Gordon, D.; Christiano, A. M. (2008). "Disruption of P2RY5, an orphan G protein–coupled receptor, underlies autosomal recessive woolly hair". Nature Genetics 40 (3): 335–339. doi:10.1038/ng.100. PMID 18297072.
- Sprecher, E. (2008). "Disentangling the roots of inherited hair disorders". Nature Genetics 40 (3): 265–266. doi:10.1038/ng0308-265. PMID 18305473.
- Kiso, M.; Tanaka, S.; Saba, R.; Matsuda, S.; Shimizu, A.; Ohyama, M.; Okano, H. J.; Shiroishi, T.; Okano, H.; Saga, Y. (2009). "The disruption of Sox21-mediated hair shaft cuticle differentiation causes cyclic alopecia in mice". Proceedings of the National Academy of Sciences 106 (23): 9292–9297. doi:10.1073/pnas.0808324106. PMC 2695080. PMID 19470461.
- Kawaminami, S.; Breakspear, S.; Saga, Y.; Noecker, B.; Masukawa, Y.; Tsuchiya, M.; Oguri, M.; Inoue, Y.; Ishikawa, K.; Okamoto, M. (2012). "Deletion of theSox21gene drastically affects hair lipids". Experimental Dermatology 21 (12): 974–976. doi:10.1111/exd.12050. PMID 23171466.
- "Medical Treatments for Balding in Men", April 1999, American Family Physician (medical journal)