Donor Variation And Sex Hormone Receptors In Periodontal Ligament Cells

Objective: This study evaluated the gene expression and protein synthesis of sex hormone receptors in human periodontal ligament cells (PDLCs) in relation to donor- and tooth-specific factors with the aim to clarify the debate about sex hormone receptors in PDLCs.Design: The expression patterns of estrogen receptors (genes: ESR1 and ESR2; proteins: ER alpha and ER beta), androgen receptor (AR) and progesterone receptor (PR) were investigated in the context of immortalization status, previous orthodontic tooth movement (OTM), donor age, sex and hormonal stimulation in PDLCs from 14 healthy donors (male: n = 8, female: n = 6; adolescents: n = 8, adults: n = 6) using quantitative real-time polymerase chain reaction, Western blot and immunocytochemistry.Results: For ER beta, the full-length isoform ER beta 1 and truncated variants were detected. For ER alpha, the expected isoform ER alpha 66 was not observed, but a novel isoform ER alpha 36 was detected. Immortalization status, previous OTM and donor age had no impact on ESR1 and ESR2 expression. Estradiol stimulation for 24 h doubled the ratio of ESR2/ESR1 in PDLCs from female but not male donors, indicating sex-specific patterns of receptor expression. AR and PR demonstrated insufficient protein synthesis in PDLCs.Conclusions: The data revealed a pivotal role for and complex interplay between ER alpha and ER beta in human PDLCs regardless of variable donor characteristics. Therefore, PDLC biology might be altered in patients of each age group and both sexes due to hormonal changes. This should be kept in mind during periodontic and orthodontic treatment of patients with special hormonal status.