Came across this, found it interesting to note that minocycline (an antibiotic) increased 5AR activity (albeit in Gingival fibroblasts inthe mouth).
Note: The tissues that surround and support the teeth are collectively called the periodontium.
ncbi.nlm.nih.gov/pubmed/9477 … PlusDrugs1
Effects of the anti-androgen finasteride on 5alpha-reductase activity in human gingival fibroblasts in response to minocycline.
Soory M, Virdi H.
Department of Periodontology, King’s College School of Medicine & Dentistry, London, United Kingdom.
In addition to their antimicrobial properties, tetracyclines have antiinflammatory and pro-anabolic effects on the reparatory potential of connective tissue and bone.
The physiologically active androgen 5alpha-dihydrotestosterone (DHT) implicated in matrix synthesis is formed in gingivae from androgen substrates.
The aim of this investigation is to study the androgen metabolic response of gingivae to minocycline, in the presence or absence of the anti-androgen finasteride. Chronically inflamed gingival tissue derived from 12 subjects aged 30-50 years and passaged fibroblasts derived from this source, were used for the experiments.
Duplicate incubations were performed in Eagle’s MEM with 14C-testosterone/14C-4-androstenedione in the presence or absence of minocycline (5-60 microg/ml) or finasteride for 24 h.
The androgen substrate 14C-testosterone was metabolised mainly to DHT and 4-androstenedione, while 14C-4-androstenedione was converted mainly to DHT and testosterone.
Minocycline at 20-30 microg/ml stimulated the formation of these metabolites from both substrates by 13-25%. In the tissue incubations there were 3- and 2-fold increases in DHT and 4-androstenedione formation (n=12; p<0.01).
The anti-androgen finasteride caused significant inhibition of 5alpha-reductase activity on both substrates at 0.1 & 1.0 microg/ml with total inhibition at 10 & 50 microg/ml (n=3; p<0.01). Minocycline-induced stimulation of 5alpha-reductase activity was also inhibited by finasteride (n=4; p<0.02).
Since finasteride inhibition of 5alpha-reductase activity is specific for the type 2 isoenzyme associated with anabolic functions of target tissue, this enzyme activity may contribute to some of the cited anabolic tissue responses to minocycline.
PMID: 9477022 [PubMed - indexed for MEDLINE]
ncbi.nlm.nih.gov/pubmed/1070 … 20Propecia
The effect of minocycline on the metabolism of androgens by human oral periosteal fibroblasts and its inhibition by finasteride.
Soory M, Tilakaratne A.
Department of Periodontology, GKT Dental Institute, King’s College, Caldecot Road, London, UK.
The antimicrobial minocycline has matrix-stimulatory effects on connective tissue and bone. The aim here was to study the effect of minocycline on 5alpha reduction of androgen substrates to 5alpha-dihydrotestosterone (DHT) in periosteal fibroblasts and the influence of the antiandrogen finasteride on this conversion.
Confluent cultures of periosteal fibroblasts established from oral periosteum isolated from the bone surface were incubated in duplicate in multiwell dishes with two androgen substrates, [(14)C]-testosterone/[(14)C]-4-androstenedione, in the presence or absence of serial concentrations of minocycline or the antiandrogen finasteride or the two in combination for 24 h.
The metabolites formed were solvent-extracted with ethyl acetate, separated by thin-layer chromatography and quantified using a radioisotope scanner. Both androgen substrates were metabolized to DHT and 4-androstenedione or testosterone.
Minocycline stimulated the synthesis of DHT from these substrates by 75-83% at 20-30 microg/ml (n=4; p<0.01). Finasteride inhibited the 5alpha-reductase activity of these substrates by 3-5-fold at 1 microg/ml and 40-80% at 0.01 and 0.1 microg/ml (n=4; p<0.01), with little change in 17beta-hydroxysteroid dehydrogenase activity.
Minocycline and finasteride in combination showed an intermediate response with one substrate.
As finasteride inhibits the type 2, 5alpha-reductase isoenzyme associated with anabolic functions, these findings demonstrate target-tissue androgen metabolic activity in periosteal fibroblasts at baseline and in response to minocycline.
This has implications for the reparatory potential of the diseased periodontium during adjunctive treatment with minocycline.
PMID: 10708666 [PubMed - indexed for MEDLINE]