TLDR People with alopecia areata have higher levels of osteopontin, which might be important in the disease's development, but this doesn't relate to how severe the disease is.
The study compared osteopontin (OPN) expression in 28 patients with alopecia areata (AA) to 25 healthy controls, using real-time PCR and immunohistochemistry. Results showed significantly higher OPN levels in AA patients, with PCR levels at 4.5–12.8 (mean 8.93 ± 1.9) and immunohistochemical expression at 7.1–21.2% (mean 12 ± 5.5%), against controls with levels of 1-4.6 (mean 2.11 ± 0.93) and 3.9-12.02% (mean 6.8 ± 2.8%), respectively, and p < 0.0000 for both methods. No significant correlation was found between OPN mRNA expression and the Severity of Alopecia Tool score. The study concluded that the high expression of OPN mRNA is associated with AA and may play a significant role in its pathogenesis, despite the lack of correlation with disease severity.
66 citations,
May 2011 in “Dermatologic therapy” Guidelines help design better trials to compare alopecia areata treatments.
109 citations,
May 2011 in “Dermatologic Therapy” Alopecia areata is a type of hair loss that can lead to complete baldness, often associated with other autoimmune conditions, and half of the cases may see hair return within a year.
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391 citations,
January 2010 in “Journal of The American Academy of Dermatology” Half of people with Alopecia Areata may see hair regrowth within a year without treatment, but recovery is unpredictable.
185 citations,
August 2005 in “Autoimmunity Reviews” Alopecia areata is an autoimmune condition causing hair loss due to the immune system attacking hair follicles, often influenced by genetics and stress.
17 citations,
December 2001 in “Journal of Investigative Dermatology” The osteopontin gene is active in a specific part of rat hair follicles during a certain hair growth phase and might affect hair cycle and diseases.
27 citations,
September 1999 in “Journal of Investigative Dermatology” Human skin cells contain Protease Nexin-1, and male hormones can decrease its levels, potentially affecting hair growth.
176 citations,
August 2015 in “The journal of allergy and clinical immunology/Journal of allergy and clinical immunology/The journal of allergy and clinical immunology” Alopecia areata involves immune activation in the scalp, suggesting treatments targeting TH1, TH2, and IL-23 pathways.
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