Endocrine Abstracts

Nicotine has been reported to have detrimental effects on fibroblasts while androgen metabolites and oestradiol are potentially anabolic. The aim of this investigation is to study the effects of oestradiol and nicotine on androgen metabolism as an index of healing. Monolayer cultures of human gingival fibroblasts (Approved by the local Ethics Committee) were established in Eagle's MEM with 14C-testosterone / 14C-4-androstenedione (4-A) as substrates. (Nicotine (N:1,50 microgram/ml) and oestradiol (O:1microgram/ml) were added alone and in combinations of N1+O and N50+O. After a 24h incubation period, the medium was solvent extracted for steroid metabolites, which were separated by thin layer chromatography and quantified using a radioisotope scanner. N1 caused 26% stimulation in DHT synthesis while N50 inhibited DHT synthesis by 23% over controls (n=6; p<0.01). There was 66% stimulation of DHT yields in response to O1, while the combinations of O1 with N1 and N50 respectively, showed 29% and 43% less stimulation than with O1 alone (n=6; p<0.01). There was not much change in the yields of 4-A. Similar trends were seen with 14C-4-A as substrate. The decreased androgen metabolic response of fibroblasts to higher concentrations of nicotine could reflect impaired healing responses. Some of the detrimental effets of higher concentations of nicotine on fibroblasts may be diminished by oestradiol.