Analysis of Interleukin-Activated Human Gingival Fibroblasts: Modulation of Chemokine Responses by Female Hormones

Consideration of hormonal changes for orthodontic treatment during pregnancy and lactation - a review

Hormonal changes in pregnant and lactating women significantly affect bone metabolism and overall stress levels, positioning them as a unique group within the orthodontic population. Fluctuations in estrogen, progesterone, prolactin, and other hormones are closely linked to bone remodeling and the periodontal tissue's response to inflammation caused by dental plaque. Hormones such as thyrotropin, leptin, and melatonin also play crucial roles in pregnancy and bone remodeling, with potential implications for orthodontic tooth movement. Additionally, adverse personal behaviors and changes in dietary habits worsen periodontal conditions and complicate periodontal maintenance during orthodontic treatment. Notably, applying orthodontic force during pregnancy and lactation may trigger stress responses in the endocrine system, altering hormone levels. However, these changes do not appear to adversely affect the mother or fetus. This review comprehensively examines the interaction between hormone levels and orthodontic tooth movement in pregnant and lactating women, offering insights to guide clinical practice.

The effect of sex steroid hormones on the ecology of in vitro oral biofilms

Sex steroid hormones (SSH) such as oestrogen, progesterone and testosterone are cholesterol derived molecules that regulate various physiological processes. They are present in both blood and saliva, where they come in contact with oral tissues and oral microorganisms. Several studies have confirmed the effect of these hormones on different periodontal-disease-associated bacteria, using single-species models. Bacteria can metabolize SSH, use them as alternative for vitamin K and also use them to induce the expression of virulence factors. However, it is still unclear what the effects of SSH are on the oral microbiome. In this study, we investigated the effects of four SSH on commensal in vitro oral biofilms. Saliva-derived oral biofilms were grown in Mc Bain medium without serum or menadione using the Amsterdam Active-Attachment model. After initial attachment in absence of SSH, the biofilms were grown in medium containing either oestradiol, oestriol, progesterone or testosterone at a 100-fold physiological concentration. Menadione or ethanol were included as positive control and negative control, respectively. After 12 days with daily medium refreshments, biofilm formation, biofilm red fluorescence and microbial composition were determined. The supernatants were tested for proteolytic activity using the Fluorescence Resonance Energy Transfer Analysis (FRET). No significant differences were found in biofilm formation, red fluorescence or microbial composition in any of the tested groups. Samples grown in presence of progesterone and oestradiol showed proteolytic activity comparable to biofilms supplemented with menadione. In contrast, testosterone and oestriol showed a decreased proteolytic activity compared to biofilms grown in presence of menadione. None of the tested SSH had large effects on the ecology of in vitro oral biofilms, therefore a direct translation of our results into in vivo effects is not possible. Future experiments should include other host factors such as oral tissues, immune cells and combinations of SSH as present in saliva, in order to have a more accurate picture of the phenomena taking place in both males and females.

Gender differences in immunological response of African-American juveniles with Grade C molar incisor pattern periodontitis

BACKGROUND

Prevalence of Grade C molar incisor periodontitis (C/MIP) in females (F) and males (M) is controversial, although some studies suggest higher prevalence in females. The objective of this study was to evaluate differences in clinical parameters, and levels of cyto/chemokines in gingival crevicular fluid (GCF) and peripheral blood response.

METHODS

GCF and blood were collected from 79 C/MIP African-American participants (53F and 26 M) and healthy controls (58F and 38 M), aged 5 to 23. Blood was stimulated with ultrapure LPS from Escherichia coli (Ec) and Porphyromonas gingivalis (Pg) and we quantified levels of 14 cyto/chemokines. Clinical parameters were collected before and 12 months following treatment RESULTS: No clinical parameters or age differences were found between males and females, although age was negatively correlated with response to treatment. GCF levels of TNFα, IFNγ, MIP1α, and MCP1 from diseased and sites and healthy sites IFNγ levels were higher in M (P < 0.05). C/MIP females presented higher Pg and Ec LPS induced levels of Eotaxin, IFNγ, and GMCSF (P < 0.05), whereas healthy males presented higher Ec LPS induced levels of Eotaxin and IFNγ (P < 0.05). Inflammatory profiles were also different among genders in disease (P = 0.004).

CONCLUSIONS

Although males seemed to present few elevated inflammatory markers in the GCF in disease and in health, females presented an elevated systemic inflammatory response to LPS in disease, which indicates a possible differential susceptibility to inflammation. Future studies need to determine if sex hormones have a role in the peripheral host response and in the pathogenesis of C/MIP.

The role of CXC chemokine ligand 16 in physiological and pathological pregnancies

The survival and development of a semi-allogeneic fetus during pregnancy require the involvement of a series of cytokines and immune cells. Chemokines are a type of special cytokine those were originally described as having a role in leukocyte trafficking. CXC chemokine ligand (CXCL) 16 is a member of the chemokine family, and CXC chemokine receptor (CXCR) 6 is its sole receptor. Emerging evidence has shown that CXCL16/CXCR6 is expressed at the maternal-fetal interface, by cell types that include trophoblast cells, decidual stroma cells, and decidual immune cells (eg, monocytes, γδT cells, and natural killer T (NKT) cells). The regulation of expression of CXCL16 is quite complex, and this process involves a multitude of factors. CXCL16 exerts a critical role in the establishment of a successful pregnancy through a series of molecular interactions at the maternal-fetal interface. However, an abnormal expression of CXCL16 is associated with certain pathological states associated with pregnancy, including recurrent miscarriage, pre-eclampsia, and gestational diabetes mellitus (GDM). In the present review, the expression and pleiotropic roles of CXCL16 under conditions of physiological and pathological pregnancy are systematically discussed.

Multiple functions of gingival and mucoperiosteal fibroblasts in oral wound healing and repair

Fibroblasts are cells of mesenchymal origin. They are responsible for the production of most extracellular matrix in connective tissues and are essential for wound healing and repair. In recent years, it has become clear that fibroblasts from different tissues have various distinct traits. Moreover, wounds in the oral cavity heal under very special environmental conditions compared with skin wounds. Here, we reviewed the current literature on the various interconnected functions of gingival and mucoperiosteal fibroblasts during the repair of oral wounds. The MEDLINE database was searched with the following terms: (gingival OR mucoperiosteal) AND fibroblast AND (wound healing OR repair). The data gathered were used to compare oral fibroblasts with fibroblasts from other tissues in terms of their regulation and function during wound healing. Specifically, we sought answers to the following questions: (i) what is the role of oral fibroblasts in the inflammatory response in acute wounds; (ii) how do growth factors control the function of oral fibroblasts during wound healing; (iii) how do oral fibroblasts produce, remodel and interact with extracellular matrix in healing wounds; (iv) how do oral fibroblasts respond to mechanical stress; and (v) how does aging affect the fetal-like responses and functions of oral fibroblasts? The current state of research indicates that oral fibroblasts possess unique characteristics and tightly controlled specific functions in wound healing and repair. This information is essential for developing new strategies to control the intraoral wound-healing processes of the individual patient.

Relationship between gingival inflammation and pregnancy

An increase in the prevalence and severity of gingival inflammation during pregnancy has been reported since the 1960s. Though the etiology is not fully known, it is believed that increasing plasma sex steroid hormone levels during pregnancy have a dramatic effect on the periodontium. Current works of research have shown that estrogen and progesterone increasing during pregnancy are supposed to be responsible for gingivitis progression. This review is focused not only on epidemiological studies, but also on the effects of progesterone and estrogen on the change of subgingival microbiota and immunologic physiological mediators in periodontal tissue (gingiva and periodontal ligament), which provides current information about the effects of pregnancy on gingival inflammation.

Different effects of P. gingivalis LPS and E. coli LPS on the expression of interleukin-6 in human gingival fibroblasts

OBJECTIVE

Gingival fibroblasts (GFs) produce pro-inflammatory cytokines in response to stimulation with lipopolysaccharide (LPS) of Porphyromonas gingivalis, which is thought to be mediated by activation of toll-like receptors (TLR)2 and TLR4. The present study investigated the expression of interleukin (IL)-6, TLR2, and TLR4 in GFs of seven different donors upon stimulation with P. gingivalis LPS. The effects of P. gingivalis LPS were compared with those of TLR4 agonist Escherichia coli LPS and TLR2 agonist Pam3CSK4.

MATERIALS AND METHODS

GFs were stimulated with P. gingivalis LPS, E. coli LPS or Pam3CSK4 and the expression of IL-6, TLR2 and TLR4 was measured by qPCR. The surface expression of TLR2 and TLR4 was measured by flow cytometry.

RESULTS

In GFs from three donors, P. gingivalis LPS and Pam3CSK4 induced a markedly lower increase in IL-6 expression than E. coli LPS. This was accompanied by significant down-regulation of the TLR2 and TLR4 expression. In GFs from another four donors, an increase in IL-6 expression upon stimulation with P. gingivalis LPS and Pam3CSK4 was similar or even higher than that induced by E. coli LPS. In GFs of these donors, all stimuli induced an up-regulation of both mRNA and protein expression of TLR2 and did not influence that of TLR4.

CONCLUSIONS

This study suggests that P. gingivalis LPS and E. coli LPS differently regulate cytokine production in human gingival fibroblasts. Regulation of the expression level of TLR2 and TLR4 by periodontal pathogens might be an important factor controlling the inflammatory response in GFs.

Influence of combined oral contraceptives on the periodontal condition

Most studies investigating the impact of oral contraceptives have been performed some years ago, when the level of sexual hormones was greater than the actual formulations.

OBJECTIVE

The aim of this study was to evaluate the effects of current combined oral contraceptives (COC) on periodontal tissues, correlating the clinical parameters examined with the total duration of continuous oral contraceptive intake.

MATERIAL AND METHODS

Twenty-five women (19-35 years old) taking combined oral contraceptives for at least 1 year were included in the test group. The control group was composed by 25 patients at the same age range reporting no use of hormone-based contraceptive methods. Clinical parameters investigated included pocket probing depth (PD), clinical attachment level (CAL), sulcular bleeding index (SBI) and plaque index (Pl.I). Data were statistically evaluated by unpaired t test, Pearson's correlation test and Spearman's correlation test.

RESULTS

The test group showed increased PD (2.228±0.011 x 2.154±0.012; p<0.0001) and SBI (0.229±0.006 x 0.148±0.005, p<0.0001) than controls. No significant differences between groups were found in CAL (0.435±0.01 x 0.412±0.01; p=0.11). The control group showed greater Pl.I than the test group (0.206±0.007 x 0.303±0.008; p<0.0001). No correlation between the duration of oral contraceptive intake, age and periodontal parameters was observed.

CONCLUSIONS

These findings suggest that the use of currently available combined oral contraceptives can influence the periodontal conditions of the patients, independently of the level of plaque accumulation or total duration of medication intake, resulting in increased gingival inflammation.