J Proteomics. 2011 Nov 18;74(12):2760-73. Epub 2011 Oct 2.
Impact of taxol on dermal papilla cells--a proteomics and bioinformatics analysis.
Dermal papilla (DP) cells play a regulatory role in hair growth and regrowth, and also play a role in alopecia (hair loss). However, effects of taxol, which is a widely used chemotherapy drug, on DP cells remain unclear, despite that theoretically taxol can impact on DP cells to contribute to taxol-induced alopecia. To better understand pathophysiology of taxol-induced damage in DP cells, morphological and biochemical analyses were performed to check whether taxol can cause apoptosis in cultured DP cells or not. If it can, proteomics and bioinformatics analyses were then performed to investigate the protein networks which are impacted by the taxol treatment. Our data showed that taxol can cause apoptotic damage in DP cells in a concentration-dependant manner, as demonstrated by various apoptotic markers. Proteomic analysis on DP cells treated with the lowest apoptosis-inducible concentration of taxol revealed that taxol can affect expression of proteins involved in Ca2+-regulated biological processes, vesicles transport, protein folding, reductive detoxification, and biomolecules metabolism. Furthermore, bioinformatics analysis indicated that taxol can impact on multiple biological networks. Taken together, this biochemical, proteomics, and bioinformatics data may give an insight into pathophysiology of taxol-induced damage in DP cells and shed light on mechanisms underlying taxol-induced hait-loss.
Vitamin-D and hair loss and hair regrowth
Dermatol Online J. 2010;16:3.
Does D matter? The role of vitamin D in hair disorders and hair follicle cycling.
Amor KT, et al
"...Limited studies have been done in humans to elaborate the role of vitamin D in the hair cycle. A potential application for vitamin D is in chemotherapy-induced hair loss. Topical calcitriol has been shown to protect against chemotherapy-induced alopecia caused by paclitaxel and cyclophosphamide. However, topical calcitriol failed to protect against chemotherapy-induced hair loss caused by a combination of 5-fluorouracil, doxorubicin, and cyclophosphamide and a combination of cyclophosphamide, methotrexate, and 5-fluorouracil [36, 37]. The ability of topical calcitriol to prevent chemotherapy-induced alopecia may therefore depend on the chemotherapy agents used. Of note, the studies in which no effects were observed, were small and may have used doses of vitamin D that were inadequate to protect against chemotherapy-induced hair loss....
Another potential application for vitamin D is in hair loss due to scalp psoriasis, which is associated with an increased telogen to anagen ratio. Although vitamin D3 analogs have been used in combination or as an alternative to topical steroids to treat scalp psoriasis for many years, their ability to combat the associated hair loss has not been thoroughly evaluated. A placebo-controlled trial with 26 patients showed that calcipotriol did not affect the telogen to anagen ratio after 6 weeks of treatment, but the optimal effect of calcipotriol on scalp psoriasis is not seen until 8 weeks. Thus, the follow up may have been too brief to detect an effect of calcipotriol on hair loss.
An optimal concentration of vitamin D may be necessary to delay the aging phenomena, including hair loss. A cross sectional study of 296 healthy men was done to determine the association, if any, between male pattern baldness and serum 25-hydroxyvitamin D levels. Based on this study, the extent and severity of male pattern baldness does not appear to be associated with serum 25-hydroxyvitamin D levels . Additional studies in subjects with age-related or senescent hair thinning as well as in women with female pattern hair loss could be considered to see if there is an association of hair loss with serum 25-hydroxyvitamin D levels.
Because it is known that the absence of VDR leads to hair loss, it was hypothesized that there may be VDR gene polymorphisms (Bsml, Apal, and Taql) in patients with alopecia areata. A study of VDR genotypes in 32 patients with alopecia areata and 27 controls showed no association between these VDR gene polymorphisms and alopecia areata. A separate study also showed that there was no relationship between the VDR gene FokI polymorphism and hair loss due to alopecia areata......
edited for hair loss blog
Hair loss and hair loss treatment
Canine hypothyroidism and hair loss
J Am Vet Med Assoc. 1980 Dec 1;177(11):1117-22.
Canine hypothyroidism: a retrospective study of 108 cases.
Nesbitt GH, Izzo J, Peterson L, Wilkins RJ.
Hypothyroidism, defined as a serum concentration of less than 70 ng of triiodothyronine (T3)/dl or less than 1.5 microgram of thyroxine (T4)/dl, or both, was diagnosed in 108 dogs by means of radioimmunoassay techniques. Both T3 and T4 values were determined in 96 dogs. Both values were low in approximately 50% (47/96) of the hypothyroid dogs; 25% (24/96) were T3 hypothyroid (low T3, normal T4), and 26% (25/96) were T4 hypothyroid (normal T3, low T4). The T3 values varied markedly between animals. Common clinical signs were hair loss, changes in coat (dryness, dullness, dandruff, scales, coarseness, and slow hair regrowth), hyperpigmentation, and pyoderma. Doberman Pinschers, Great Danes, Poodles, Schnauzers, Irish Setters, and Boxers accounted for 50% (54/108) of the hypothyroid dogs. Therapy consisted of T4, T3, or combination T3 and T4 replacement. A good clinical response was observed with T4 replacement in 40.4% (19/47) within 2 months and in 21.3% (10/47) within 5 months. A poor clinical response was observed in 25.5% (12/47) after 6 months of therapy. Posttherapeutic evaluation was based on peak serum concentrations of T3 and T4, pretreatment (basal) thyroid hormone values, type of replacement therapy, dosage and time of sampling after treatment, concurrent clinical problems, and, most important, clinical response to thyroid replacement therapy.