Fluoxetine inhibits inflammatory response and bone loss in a rat model of ligature-induced periodontitis

Influence of antidepressant use on periodontal status: a systematic review and meta-analysis

OBJECTIVE

The aim of this review was to evaluate the influence of antidepressant use on inflammatory and clinical data related to periodontal status in animal and human studies.

MATERIALS AND METHODS

A systematic review was conducted according to the PRISMA guidelines. The potential risk of bias was assessed using the SYRCLE RoB or the Joanna Briggs Institute tools. For human studies, a meta-analysis was performed to compare periodontal parameters between users and non-users of antidepressants, and to estimate the mean difference using random effects models.

RESULTS

Twelve studies met the inclusion criteria: eight were conducted on animal models, and four were human studies. Tianeptine, desipramine, imipramine, and fluoxetine effectively reduced alveolar bone loss in experimental periodontitis. Furthermore, desipramine, imipramine, and fluoxetine were observed to reduce the expressions of inflammatory markers in gingival tissue. The meta-analysis found no differences in the influence of antidepressant use on periodontal pocket depth, clinical attachment level, and gingival index between users and non-users. There was no standardization of the duration of use, type, and dosage of medication between studies.

CONCLUSIONS

Animal studies suggest antidepressants modulate the immunoinflammatory response and prevent alveolar bone loss in experimental periodontitis, but their impact on human periodontal status remains controversial. Standardized methods are needed to clarify antidepressant effects on the periodontium.

CLINICAL RELEVANCE

This study informs health professionals that certain antidepressants may positively impact the periodontium, while also highlighting the need for further research evaluating their possible influence on the human periodontal condition and their potentially associated local/systemic adverse effects.

Microbiota-immune-brain interactions: A new vision in the understanding of periodontal health and disease

This review highlights the significance of interactions between the microbiota, immune system, nervous and hormonal systems, and the brain on periodontal health and disease. Microorganisms in the microbiota, immune cells, and neurons communicate via homeostatic nervous and hormonal systems, regulating vital body functions. By modulating pro-inflammatory and anti-inflammatory adaptive immune responses, these systems control the composition and number of microorganisms in the microbiota. The strength of these brain-controlled responses is genetically determined but is sensitive to early childhood stressors, which can permanently alter their responsiveness via epigenetic mechanisms, and to adult stressors, causing temporary changes. Clinical evidence and research with humans and animal models indicate that factors linked to severe periodontitis enhance the responsiveness of these homeostatic systems, leading to persistent hyperactivation. This weakens the immune defense against invasive symbiotic microorganisms (pathobionts) while strengthening the defense against non-invasive symbionts at the gingival margin. The result is an increased gingival tissue load of pathobionts, including Gram-negative bacteria, followed by an excessive innate immune response, which prevents infection but simultaneously destroys gingival and periodontal tissues. Thus, the balance between pro-inflammatory and anti-inflammatory adaptive immunity is crucial in controlling the microbiota, and the responsiveness of brain-controlled homeostatic systems determines periodontal health.

Deciphering the Biological Aging Impact on Alveolar Bone Loss: Insights From α-Klotho and Renal Function Dynamics

Alveolar bone loss is generally considered a chronological age-related disease. As biological aging process is not absolutely determined by increasing age, whether alveolar bone loss is associated with increasing chronological age or biological aging remains unclear. Accurately distinguishing whether alveolar bone loss is chronological age-related or biological aging-related is critical for selecting appropriate clinical treatments. This study aimed to identify the relationship between alveolar bone loss and body aging. In total, 3 635 participants from the National Health and Nutrition Examination Survey and 71 living kidney transplant recipients from Gene Expression Omnibus Datasets were enrolled. Multivariate regression analysis, smooth curve fittings, and generalized additive models were used to explore the association among alveolar bone loss, age, serum α-Klotho level, renal function markers, as well as between preoperative creatinine and renal cortex-related α-Klotho gene expression level. Meanwhile, a 2-sample Mendelian randomization (MR) study was conducted to assess the causal relationship between α-Klotho and periodontal disease (4 376 individuals vs 361 194 individuals). As a biological aging-related indicator, the α-Klotho level was negatively correlated with impaired renal function and alveolar bone loss. Correspondingly, accompanied by decreasing renal function, it was manifested with a downregulated expression level of α-Klotho in the renal cortex and aggravated alveolar bone loss. The MR analysis further identified the negative association between higher genetically predicted α-Klotho concentrations with alveolar bone loss susceptibility using the IVW (odds ratio [OR] = 0.999, p = .005). However, an inversely U-shaped association was observed between chronological age and alveolar bone loss, which is especially stable in men (the optimal cutoff values were both 62 years old). For men above 62 years old, increasing age is converted to protective factor and is accompanied by alleviated alveolar bone loss. Alveolar bone loss that is directly associated with decreased renal function and α-Klotho level was related to biological aging rather than chronological age. The renal-alveolar bone axis could provide a new sight of clinical therapy in alveolar bone loss.

Periodontitis and Depressive Disorders: The Effects of Antidepressant Drugs on the Periodontium in Clinical and Preclinical Models: A Narrative Review

Background/Objectives: Several psychological conditions, including stress and depression, can adversely affect oral health; in fact, antidepressants, commonly used to treat depressive disorders, may have conflicting effects on the periodontal status of individuals. The aim of this review was to determine the effects of antidepressants on the periodontium. Methods: A literature search was conducted using electronic databases, Pubmed/MEDLINE, Cochrane Library, focusing on the use of antidepressants and their effects on periodontal health in animals or humans. Results: Seventeen articles have been included with the use of amitriptyline (two studies), desipramine (one study), imipramine (two studies), desvenlafaxine (one study), fluoxetine (six studies), venlafaxine (three studies) and tianeptine (two studies). One study evaluated several categories of antidepressants, such as selective serotonin reuptake inhibitors (SSRI), serotonin-norepinephrine reuptake inhibitors (SNRI), tricyclic, atypical and monoamine oxidase inhibitors (MAO). Most trials showed improvements in periodontal health, especially with fluoxetine, but also with imipramine, desipramine, desvenlafaxine and tianeptine; on the contrary, worsening of clinical periodontal indices and increased loss of alveolar bone were reported with venlafaxine. Conclusions: This review suggests that in the presence of comorbidity between periodontitis and depression, pharmacological treatment with SNRIs, SSRIs and mixed antidepressants is associated with improvement in periodontal parameters, except for venlafaxine. Healthcare professionals (especially oral and mental health professionals) should investigate proper adherence to medication therapy in patients with a history of periodontitis and depression. Further clinical trials are needed to confirm these results.

The multifaceted effects of fluoxetine treatment on cognitive functions

Fluoxetine, the prototypical selective serotonin reuptake inhibitor (SSRI), is widely used to treat major depressive disorder (MDD) and a variety of other central nervous system conditions, primarily due to its established clinical safety profile. Although its efficacy in treating depression is well-recognized, the impact of fluoxetine on cognitive functions remains inconsistent and elusive. In this review, we first examine the well-substantiated biological mechanisms underlying fluoxetine's antidepressant effects, which include serotonin reuptake inhibition and activation of TrkB receptors-key to brain-derived neurotrophic factor (BDNF) signaling. Subsequently, we delve into the cognitive side effects observed in both preclinical and clinical studies, affecting domains such as memory, attention, and executive functions. While certain studies indicate cognitive improvements in patients with underlying disorders, there is also evidence of negative effects, influenced by variables like gender, duration of treatment, age, disease pathology, and the specifics of cognitive testing. Significantly, the negative cognitive outcomes reported in preclinical research often involve healthy, non-diseased animals. This review underscores the necessity for heightened caution in fluoxetine prescription and further investigation into its potentially detrimental cognitive effects, even when used prophylactically.

An Update on Drug-Nutrient Interactions and Dental Decay in Older Adults

In recent decades, the global demographic landscape has undergone a discernible shift that has been characterised by a progressive increase in the proportion of elderly individuals, indicative of an enduring global inclination toward extended lifespans. The aging process, accompanied by physiological changes and dietary patterns, contributes to detrimental deviations in micronutrient consumption. This vulnerable aging population faces heightened risks, including dental caries, due to structural and functional modifications resulting from insufficient nutritional sustenance. Factors such as physiological changes, inadequate nutrition, and the prevalence of multiple chronic pathologies leading to polypharmacy contribute to the challenge of maintaining an optimal nutritional status. This scenario increases the likelihood of drug interactions, both between medications and with nutrients and the microbiome, triggering complications such as dental decay and other pathologies. Since the drug industry is evolving and new types of food, supplements, and nutrients are being designed, there is a need for further research on the mechanisms by which drugs interfere with certain nutrients that affect homeostasis, exemplified by the prevalence of caries in the mouths of older adults. Infectious diseases, among them dental caries, exert serious impacts on the health and overall quality of life of the elderly demographic. This comprehensive review endeavours to elucidate the intricate interplay among drugs, nutrients, the microbiome, and the oral cavity environment, with the overarching objective of mitigating the potential hazards posed to both the general health and dental well-being of older adults. By scrutinising and optimising these multifaceted interactions, this examination aims to proactively minimise the susceptibility of the elderly population to a spectrum of health-related issues and the consequences associated with dental decay.

Periodontal and peri-implant status and whole salivary interleukin 1-beta levels among individuals using selective serotonin reuptake inhibitors: an observational study

OBJECTIVE

Selective serotonin reuptake inhibitors (SSRI) are commonly used for managing psychological diseases such as depression. These disorders are also directly associated with periodontal and peri-implant diseases, namely periodontitis and peri-implantitis, respectively. It is hypothesized that there is no difference in periodontal and peri-implant clinicoradiographic status and unstimulated whole salivary interleukin (IL)-1β levels in participants using selective serotonin reuptake inhibitors (SSRI) and controls (individuals not using SSRI). The aim of the present observational case-control study was to compare periodontal and peri-implant clinicoradiographic statuses and whole salivary IL-1β in participants using SSRI and controls.

METHODS

Users of SSRI and controls were included. In all participants, periodontal (plaque index [PI], gingival index [GI], probing depth [PD], clinical attachment loss [AL] and marginal bone loss [MBL]) and peri-implant (modified PI [mPI], modified GI [mGI], PD and crestal bone loss [CBL]) were assessed. Unstimulated whole saliva was collected and IL-1β levels were determined. Information related to duration of implants in function, duration of depressive symptoms and treatment of depression was retrieved from healthcare records. Sample-size was estimated using 5% error and group comparisons were performed. P < 0.05 was considered statistically significant.

RESULTS

Thirty-seven SSRI users and 35 controls were assessed. Individuals using SSRI had a history of depression of 4.2 ± 2.5 years. The mean age of SSRI-users and controls were 48.7 ± 5.7 and 45.3 ± 5.1 years, respectively. Tooth brushing twice daily was reported by 75.7% and 62.9% SSRI-users and controls, respectively. There was no statistically significant difference in PI, mPI, GI, mGI, PD, clinical AL, numbers of MT and mesial and distal MBL and CBL among individuals using SSRI compared with controls (Tables 3 and 4). The unstimulated whole salivary flow rate in individuals using SSRI and controls was 0.11 ± 0.003 and 0.12 ± 0.001 ml/min, respectively. Whole salivary IL-1β levels in individuals using SSRI and controls were 57.6 ± 11.6 pg/ml and 34.6 ± 5.2 pg/ml, respectively.

CONCLUSION

Users of SSRI and controls demonstrate healthy periodontal and peri-implant tissue statuses with no marked differences in whole salivary IL-1β levels provided oral hygiene is stringently maintained.

Cinnamaldehyde modulates host immunoinflammatory responses in rat ligature-induced periodontitis and peripheral blood mononuclear cell models

Cinnamaldehyde is a natural product with anti-inflammatory and immune-modulatory properties, known to regulate host responses to bacterial stimuli. This study aimed to investigate the effects of cinnamaldehyde on ligature-induced periodontitis in rats, and its impact on the modulation of human peripheral blood mononuclear cells (PBMC). Male Wistar rats were assigned into three groups:i) control: no ligature + vehicle; ii) ligature: ligature + vehicle; and iii) ligature + cinnamaldehyde (50 mg/kg); all treatments by daily oral gavage. After 14 days of induced periodontitis, the hemimandibles were collected for bone loss evaluation. The gingival levels of IL-1β, MMP-9 and iNOS mRNA were evaluated. Nitric oxide (NO) was measured in both rat saliva and plasma. PBMC were stimulated with Aggregatibacter actinomycetemcomitans (Aa) in the presence or absence of cinnamaldehyde (5, 20 e 40 µM), and cytokine production was quantified in cell supernatant. Proliferating lymphocytes were taken for flow cytometer reading, while culture supernatants were used for IFN-γ and IL-10 assessment. The ligature group had both increased alveolar bone loss and gingival expression of IL-1β, MMP-9 and iNOS compared to the control group. All parameters were attenuated by cinnamaldehyde treatment. Lower salivary but not plasma NO was detected in the cinnamaldehyde compared to the ligature group. Aa-stimulated PBMCs treated with cinnamaldehyde produced less IL-1β; the compound also attenuated lymphocyte proliferation in a dose-dependent manner, as well as cell IL-10 production. Cinnamaldehyde treatment reduced periodontal bone loss, and downregulated key inflammatory mediators and human PBMC responses, pointing to novel potential therapeutic effects of this compound.

Effect of mechanical instrumentation with adjunct photodynamic therapy on salivary TNFα levels and clinical periodontal and peri‑implant status in patients with depression: A randomized controlled trial

INTRODUCTION

The aim of the present randomized controlled trial was to assess the effect of mechanical instrumentation (MI) with adjunct photodynamic therapy (PDT) on salivary tumor necrosis factor-alpha (TNFα) levels and clinical periodontal and peri‑implant status in patients with depression.

MATERIALS AND METHODS

In groups 1 and 2, individuals with periodontal and peri‑implant diseases with and without depression, respectively were included. Group-3 comprised of systemically healthy individuals with a healthy periodontal and peri‑implant status. In groups 1 and 2, patients in the test- and control groups received MI with and without PDT respectively. Periodontal and peri‑implant probing depth and plaque and gingival indices were measured. Radiographic evaluation was done at baseline. Whole salivary tumor necrosis factor alpha (TNFα) in peri‑implant sulcular fluid were measured at baseline. The clinical and immunological parameters were reassessed at 120 days' follow-up. Level of significance was set at P<0.05.

RESULTS

Thirty-four, 36 and 37 implants were in function in groups 1, 2 and 3, respectively. At baseline, periodontal and peri‑implant clinical parameters and TNFα levels were significantly higher in groups 1 (P<0.05) and 2 (P<0.05) than Group-3. At 4-months follow-up, there was no difference in periodontal and peri‑implant clinical parameters in the test- and control groups among individuals in groups 1 and 3. In Group-2, there was a significant reduction in periodontal (P<0.05) and peri‑implant (P<0.05) clinical parameters at 4-months follow-up than baseline. In Group-2, there was no significant difference in these parameters among patients in the test- and control-groups.

CONCLUSION

In patients with depression clinical periodontal and peri‑implant status is poorer and salivary TNFα levels are higher after MI with or without PDT. In healthy patients, PDT offers no additional benefits in the treatment of periodontal inflammation.

Mental health and periodontal and peri-implant diseases

Mental health disorders, particularly depression and anxiety, affect a significant number of the global population. Several pathophysiological pathways for these disorders have been identified, including the hypothalamic-pituitary-adrenal axis, autonomic nervous system, and the immune system. In addition, life events, environmental factors, and lifestyle affect the onset, progression, and recurrence of mental health disorders. These may all overlap with periodontal and/or peri-implant disease. Mental health disorders are associated with more severe periodontal disease and, in some cases, poorer healing outcomes to nonsurgical periodontal therapy. They can result in behavior modification, such as poor oral hygiene practices, tobacco smoking, and alcohol abuse, which are also risk factors for periodontal disease and, therefore, may have a contributory effect. Stress has immunomodulatory effects regulating immune cell numbers and function, as well as proinflammatory cytokine production. Stress markers such as cortisol and catecholamines may modulate periodontal bacterial growth and the expression of virulence factors. Stress and some mental health disorders are accompanied by a low-grade chronic inflammation that may be involved in their relationship with periodontal disease and vice versa. Although the gut microbiome interacting with the central nervous system (gut-brain axis) is thought to play a significant role in mental illness, less is understood about the role of the oral microbiome. The evidence for mental health disorders on implant outcomes is lacking, but may mainly be through behaviourial changes. Through lack of compliance withoral hygiene and maintenance visits, peri-implant health can be affected. Increased smoking and risk of periodontal disease may also affect implant outcomes. Selective serotonin reuptake inhibitors have been linked with higher implant failure. They have an anabolic effect on bone, reducing turnover, which could account for the increased loss.

Matrix Metalloproteinases in Dental and Periodontal Tissues and Their Current Inhibitors: Developmental, Degradational and Pathological Aspects

Objectives: This review article aims to describe some of the roles of Matrix metalloproteinases (MMPs) in enamel, dentine, dental caries, hybrid layer degradation, pulp and periodontal tissues, throwing light on their current inhibitors. The article addresses the potential of MMPs to serve as biomarkers with diagnostic and therapeutic value. Design: The sections of this review discuss MMPs’ involvement in developmental, remodeling, degradational and turnover aspects of dental and periodontal tissues as well as their signals in the pathogenesis, progress of different lesions and wound healing of these tissues. The literature was searched for original research articles, review articles and theses. The literature search was conducted in PubMed and MEDLINE for articles published in the last 20 years. Results: 119 published papers, two textbooks and two doctoral theses were selected for preparing the current review. Conclusions: MMPs are significant proteases, of evident contribution in dental and periapical tissue development, health and disease processes, with promising potential for use as diagnostic and prognostic disease biomarkers. Continuing understanding of their role in pathogenesis and progress of different dental, periapical and periodontal lesions, as well as in dentine-pulp wound healing could be a keystone to future diagnostic and therapeutic regimens.

Fluoxetine-induced hepatic lipid accumulation is mediated by prostaglandin endoperoxide synthase 1 and is linked to elevated 15-deoxy-Δ12,14 PGJ2

Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ^12,14 PGJ₂ a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ^12,14 PGJ₂ production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ₂ and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment.

Association of different antidepressant classes with clinical attachment level and alveolar bone loss in patients with periodontitis: A retrospective study

OBJECTIVE

Our study aimed to determine the relationship of antidepressant medicine use with periodontal diseases, exploring the association of different pharmacological classes of antidepressant with observations of clinical attachment loss (CAL) and alveolar bone level (BL) in patients with periodontitis.

BACKGROUND

Existing evidence on the impact of antidepressant medication on periodontal tissues has focused on some classes only and is still unclear. Therefore, this retrospective study evaluated the association of different antidepressant classes with clinical attachment loss (CAL) and alveolar bone level (BL).

METHODS

This study was carried out in a population of patients aged ≥ 30 years old with periodontitis who sought treatment at the University of Florida from 2014 to 2018. The following variables were obtained from patients' records; usage of antidepressant medications and their pharmacological classes (selective serotonin reuptake inhibitors [SSRI], serotonin-norepinephrine reuptake inhibitors [SNRI], tricyclic, atypical, and monoamine oxidase inhibitors [MAO]), age, gender, smoking habit, mild systemic diseases, CAL, and cement-enamel junction (CEJ) and alveolar bone crest (BC) distance, defined as BL, in the Ramfjord index teeth.

RESULTS

Five hundred and eighty-two periodontitis patients were evaluated, of which 113 (19.4%) were antidepressant users. Antidepressant users exhibited significantly lower BL and fewer sites with severe CAL (≥5 mm), than non-users (p < .05). Among all single-class antidepressant users, the SSRI users showed significantly less CAL and lower BL than non-users (p < .05). Patients taking combinations of the different classes of antidepressants also showed better CAL and BL than non-users. Generalized linear models, including variables such as gender, age, systemic diseases, and smoking, demonstrated that antidepressant users were more likely to have lower mean BL and fewer sites with severe bone loss (i.e. BL > 3 and >5 mm) than non-users (p < .05).

CONCLUSIONS

Antidepressant medications were associated with higher alveolar bone level and less clinical attachment loss in patients with periodontitis. When the different classes of antidepressants were analyzed individually, only the SSRI class users and the multiple-class users showed significantly less periodontal breakdown than non-users.

Cold Atmospheric Plasma Jet as a Possible Adjuvant Therapy for Periodontal Disease

Due to the limitations of traditional periodontal therapies, and reported cold atmospheric plasma anti-inflammatory/antimicrobial activities, plasma could be an adjuvant therapy to periodontitis. Porphyromonas gingivalis was grown in blood agar. Standardized suspensions were plated on blood agar and plasma-treated for planktonic growth. For biofilm, dual-species Streptococcus gordonii + P. gingivalis biofilm grew for 48 h and then was plasma-treated. XTT assay and CFU counting were performed. Cytotoxicity was accessed immediately or after 24 h. Plasma was applied for 1, 3, 5 or 7 min. In vivo: Thirty C57BI/6 mice were subject to experimental periodontitis for 11 days. Immediately after ligature removal, animals were plasma-treated for 5 min once-Group P1 (n = 10); twice (Day 11 and 13)-Group P2 (n = 10); or not treated-Group S (n = 10). Mice were euthanized on day 15. Histological and microtomography analyses were performed. Significance level was 5%. Halo diameter increased proportionally to time of exposure contrary to CFU/mL counting. Mean/SD of fibroblasts viability did not vary among the groups. Plasma was able to inhibit P. gingivalis in planktonic culture and biofilm in a cell-safe manner. Moreover, plasma treatment in vivo, for 5 min, tends to improve periodontal tissue recovery, proportionally to the number of plasma applications.

Protective effects of desipramine on alveolar bone in experimental periodontitis

BACKGROUND

Desipramine is a tricyclic antidepressant with immune-modulatory activity, whose effects on ligature-induced periodontitis are yet to be investigated. Hence, its actions on alveolar bone resorption, gingival collagen content and key inflammatory mediators were herewith analyzed.

METHODS

A total of 60 male Wistar rats were randomly assigned into three groups: 1) control: rats without ligature treated with vehicle (saline); 2) ligature: rats with ligature-induced periodontitis treated with vehicle; 3) ligature + desipramine: rats with ligature-induced periodontitis treated with desipramine (20 mg/kg/d in vehicle). Mandibles and gingival tissues were collected 3 or 15 days after ligature insertion (or no ligature insertion for controls) and treatments. Alveolar bone resorption and gingival collagen fibers were histologically analyzed using either HE or picrosirius red staining. Gingival mRNA expressions of interleukin (IL)-1β, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 were obtained through reverse transcription polymerase chain reaction. MMP-9 activity was analyzed by zymography.

RESULTS

Alveolar bone loss was significantly reduced in the ligature + desipramine group (P < 0.05), whereas gingival collagen degradation was like the ligature group (P > 0.05). Desipramine administration downregulated mRNA expressions of IL-1β, iNOS, COX-2, and TIMP-1 when compared to vehicle alone in the ligature group (P < 0.05). MMP-9 expression and MMP-9/TIMP-1 ratio were similar among rats with ligature-induced periodontitis (P > 0.05); however, MMP-9 activity was lower in the group treated with desipramine (P < 0.05).

CONCLUSION

Desipramine administration reduced alveolar bone loss as histologically observed, and modulated key bone remodeling and inflammatory mediators in rats with ligature-induced periodontitis.

Inflammatory modulation of fluoxetine use in patients with depression: A systematic review and meta-analysis

There is growing evidence that there is a relationship between major depressive disorder (MDD), also simply known as "depression", and inflammatory processes. Selective serotonin inhibitors, such as fluoxetine, are used as a first-line treatment for depression, and it is hypothesized that its use can reduce levels of proinflammatory cytokines. The aim of this systematic review and meta-analysis is to enable a better understanding of how treatment with the antidepressant fluoxetine modulates inflammation, and the roles of the main cytokines in this process. Risk of bias (RoB) in the included studies was assessed using the Cochrane Risk of Bias Assessment tool for Non-randomized studies (RoBANS). In the meta-analysis, standardized mean difference (SMD) was used as a summary statistic and grouped statistics using the generic inverse variation method in RevMan 5 with random effects model. Heterogeneous changes in cytokine levels were also evaluated from the SMD forest plot of individual studies. After analysis, we observed that fluoxetine was able to decrease TNF-α levels (SMD ± 0.90, 95% CI = 0.16, 1.165, Z ± 2.40, p = 0.02), but not change IL-6 levels (SMD ± 0.37, 95% CI = 0.21, 0.95, Z ± 1.25, p = 0.21).Fluoxetine acts by modulating neuroimmunology, and not only by acting only on the independent restoration of neurotransmission and neuroinflammation pathways.

Effect of antidepressants on various periodontal parameters: A case-control study

Background:

Various medications are used in the treatment of chronic systemic diseases that affect the periodontium. Antidepressants in mentally depressed patients are prescribed for a long term, but their effect on the periodontium has not been studied adequately. A case–control study was conducted to know the effect of two commonly prescribed antidepressants – venlafaxine (serotonin–norepinephrine reuptake inhibitor [SNRI]) and fluoxetine (selective serotonin reuptake inhibitor [SSRI]). These drugs have been shown to possess anti-inflammatory properties but do not protect the periodontium from insults caused by these medications, which are significantly associated with the presence of destruction of the periodontium. The aim of this study was to clinically evaluate the effect of antidepressants on various periodontal parameters.

Materials and Methods:

The study sample consisted of 182 depressed patients divided into three study groups: Group I – the control group diagnosed as depressed on the first visit, Group II – depressed patients taking fluoxetine 20 mg/day, and Group III – patients taking venlafaxine 75 mg/day. Patients in Groups II and III were on isolated antidepressant medication at least for a period of 3 or more months. Mental depression in patients was assessed with the Patient Health Questionnaire-based Hamilton Depression Rating Scale with scoring of ≤16. All the depressed patients were assessed for periodontal health on the basis of the clinical periodontal parameters.

Results:

The commonly prescribed antidepressants such as fluoxetine and venlafaxine do not protect the periodontium from destruction in spite of possessing anti-inflammatory properties; therefore, these drugs may be considered as a risk factor for periodontal health. The comparative periodontal indices on nonusers of antidepressants or control group (Group I), users of SSRI (fluoxetine) (Group II), and users of antidepressants-SNRI (venlafaxine) (Group III) showed increased periodontal parameters, especially debris index (DI), calculus index (CI), gingival index (GI), periodontal pocket depth (PD), and loss in clinical attachment level. There was no significant difference for CI and GI, probing PD, and clinical attachment levels except DI which was significantly different (P ≤ 0.001).

Conclusion:

The depressed patients receiving fluoxetine or venlafaxine should be regularly evaluated for periodontal health status as these drugs are risk factors for normal periodontal tissues. Further, these medications did not protect the periodontium from periodontal inflammation, although possessing anti-inflammatory properties.

A novel Nanoformulation Development of Eugenol and their treatment in inflammation and periodontitis

OBJECTIVE

To prepare a novel nanoemulsion- Carbopol® 934 gel for Eugenol, in order to prevent the periodontitis.

MATERIAL AND METHODS

Spontaneous emulsification method was used for the preparation of nanoemulsion in which it contain Eugenol (oil phase), Tween-80 (surfactant), and PEG (co-surfactant). To the development of best nanoemulsion, three-factor three-level central composite design was used in which %oil; %Smix and % water were optimized as independent variables. An optimized-nanoemulsion were converted to nanoemulsion-Carbopol® 934 gel.

RESULTS

5.5% oil, 35.5% Smix and 59.0% water were optimized as independent and dependent variables. Finally dependent variables optimized as a particle size (nm), PDI and %transmittance were observed 79.92 ± 6.33 nm, 0.229 ± 0.019, and 98.88 ± 1.31% respectively. The values of final results for dependent variables like particle size (nm), PDI and % transmittance were evaluated as 79.92 ± 6.33 nm, 0.229 ± 0.019, and 98.88 ± 1.31%, respectively. TEM and SEM showed a spherical shape of developed nanoemulsion with refractive index (1.63 ± 0.038), zeta potential (-19.16 ± 0.11), pH (7.4 ± 0.06), viscosity (34.28 ± 6 cp), and drug content of 98.8 ± 0.09%. After that a final optimized EUG-NE-Gel was assessed on the basis of their pH measurement, drug content, syringeability, and mucoadhesion on the goat buccal mucosa. Optimized EUG-NE-Gel (Tween-80 and Carbopol® 934 used) showed the results, to improve the periodontal drug delivery of EUG in future.

CONCLUSION

EUG-NE-Gel showed a significant role in anti-inflammatory activity, analgesic, and anesthetic, antibacterial, and treatment of periodontal disease.

Serotonin and orthodontic tooth movement

Peripheral serotonin continuously reveals its unexpected involvements in many organ functions. In bone tissue, there is an increasing evidence for a local serotonergic system affecting the cellular and molecular actors involved in bone turnover. During orthodontic treatment, tooth movement relies on bone remodeling, itself a result of the inflammatory process triggered by application of orthodontic forces to the teeth. Nowadays, many adults proceed to an orthodontic treatment, it therefore seems important to consider physiological growth-related factors and external factors as medications that may influence adverse effects and efficacy of orthodontic treatment techniques. In this review, we focus on peripheral serotonin mechanism of regulation of bone remodeling during orthodontic movement. We discuss the differential effect of serotonin on alveolar bone inflammation that may open new strategies in orthodontics.

Adjunctive antimicrobial photodynamic therapy using methylene blue/ethanol formulation in experimental periodontitis in diabetic rats: short-term results

The aim of this study was to evaluate the effect of an MB experimental formulation (ethanol 20%) in aPDT used as an adjuvant to scaling and root planing (SRP) in the periodontal treatment of diabetic rats. Forty male Wistar rats received streptozotocin-intraperitonial injections to induce diabetes. After 14 days, 5 animals were allocated in the non-ligate group (NLG), and 35 animals received ligature at the first right mandibular molar to induce periodontitis. After 7 days, the ligature was removed and the animals were randomized into 4 groups: LG (without treatment, n = 5), SRPG (SRP, n = 10), aPDTW (SRP+aPDT-MB/water, n = 10), and aPDTEt (SRP + aPDT-MB/water/ethanol/carboxymethylcellulose, n = 10). Animals were euthanized after 7 days. Data of bone loss (BL) area, degree of inflammatory cell response, and collagen fibers percentages were statistically analyzed (p < 0.05). Percentage of animals that presented mild and severe inflammatory infiltrate was 10% and 40% for SRPG, 20% and 30% for aPDTW, and 50% and 0% for aPDTEt, respectively. BL area (mm²) was statistically higher in the LG (0.39 ± 0.15) than NLG (0.05 ± 0.02). aPDTEt showed the lowest value of BL (0.08 ± 0.03), followed by aPDTW (0.21 ± 0.15) and SRPG (0.31 ± 0.18). Statistical differences were verified between aPDTEt and SRPG. In relation to the LG, aPDTEt, aPDTW, and SRPG recovered the equivalent 80%, 46%, and 20% of the BL. aPDTEt showed collagen content statistically higher than SRPG and LG, and presented higher mean values than NLG (p > 0.05). Our findings showed aPDTEt presented promising results. aPDT using MB/ethanol can have potential as an adjunctive periodontal treatment in diabetics.

Periodontal, metabolic, and cardiovascular disease: Exploring the role of inflammation and mental health

Previous evidence connects periodontal disease, a modifiable condition affecting a majority of Americans, with metabolic and cardiovascular morbidity and mortality. This review focuses on the likely mediation of these associations by immune activation and their potential interactions with mental illness. Future longitudinal, and ideally interventional studies, should focus on reciprocal interactions and cascading effects, as well as points for effective preventative and therapeutic interventions across diagnostic domains to reduce morbidity, mortality and improve quality of life.

Citalopram attenuated neurobehavioral, biochemical, and metabolic alterations in transient middle cerebral artery occlusion model of stroke in male Wistar rats

Oxidative stress and inflammation are implicated as cardinal mechanisms of neuronal death following stroke. In the present study citalopram (Cit) was investigated in a 2 h middle cerebral artery occlusion (MCAo) model of stroke in male Wistar rats. Pretreatment, posttreatment (Post Cit) and pre plus posttreatment (Pre + Post Cit) with Cit were evaluated for its neuroprotective effect. In pretreatment protocol, effect of Cit at three doses (2, 4, and 8 mg/kg) administered i.p., 1 h prior to MCAo was evaluated using neurological deficit score (NDS), motor deficit paradigms, and cerebral infarction 24 h post-MCAo. In posttreatment and pre plus posttreatment protocol, the effective dose of Cit (4 mg/kg) was administered i.p., 0.5 h post-reperfusion (Post Cit) only, and 1 h prior to MCAo and again at 0.5 h post-reperfusion (Pre + Post Cit), respectively. These two groups were assessed for NDS and cerebral infarction. Though NDS was significantly reduced in both Post Cit and Pre + Post Cit groups, significant reduction in cerebral infarction was evident only in Pre + Post Cit group. Infarct volume assessed by magnetic resonance imaging was significantly attenuated in Pre + Post Cit group (10.6 ± 1.1%) compared to MCAo control group (18.5 ± 3.0%). Further, Pre + Post Cit treatment significantly altered 17 metabolites along with attenuation of malondialdehyde, reduced glutathione, matrix metalloproteinases, and apoptotic markers as compared to MCAo control. These results support the neuroprotective effect of Cit, mediated through amelioration of oxidative stress, inflammation, apoptosis, and altered metabolic profile.

Periodontal status in chronic periodontitis depressed patients on desvenlafaxine: An observational study

Background:

A wide variety of drugs have the potential to affect immune and inflammatory responses of periodontium. A class of antidepressant drug, selective serotonin and norepinephrine reuptake inhibitors, has shown anti-inflammatory function. The aim of the present study is to explore the effect of desvenlafaxine on clinical periodontal parameters in patients with chronic periodontitis.

Materials and Methods:

The patients were divided into two groups as follows: test group (n = 63) comprised of participants on 50 mg once-daily dose of desvenlafaxine for ≥2 months and control group (n = 72) included participants who were yet to be prescribed medication for depression. Periodontal parameters of both the groups were analyzed and compared statistically.

Results:

Participants taking desvenlafaxine revealed lower values of periodontal parameters as compared to those in control group. The number of pockets with greater depth and clinical attachment loss was greater in control group.

Conclusion:

In our study, patients on desvenlafaxine were associated with less pocket depth and bleeding on probing.

Melatonin and periodontal tissues: Molecular and clinical perspectives

Periodontal disease is a frequent chronic inflammatory pathology that implies the destruction of the tissues supporting the teeth, which represents a high sanitary cost. It usually appears associated with other systemic conditions such as diabetes, metabolic syndrome, depression and Alzheimer disease among others. The presence of melatonin and its receptors in the oral cavity supports the hypothesis that this hormone could play a role in homeostasis of periodontal tissues. In the present review we will discuss the potential role of melatonin, a circadian synchronizing hormone, with proved antiinflammatory and antioxidant profile, in the pathogenesis and treatment of periodontitis. Particular emphasis will be placed on the role of the indolamine in the treatment of periodontal disease when this oral condition is comorbid with other pathologies that would also benefit from the therapeutic potential of melatonin and its analogs through diverse mechanisms.

Use of antidepressive agents as a possibility in the management of periodontal diseases: A systematic review of experimental studies

Antidepressant agents have anti-inflammatory functions that could be interesting as adjuvants in periodontal therapy. The aim of the present study was to analyze the effect of antidepressive drugs in the management of periodontal disease. The MEDLINE, Scopus, Embase, LILACS, and SciELO databases were searched. To be included, the studies had to be experimental studies; randomized, controlled; double-blinded; or blinded studies. A total of 565 articles were initially searched, of which five were selected for the systematic review. All studies used rats, and three different drugs were evaluated: tianeptine, venlafaxine, and fluoxetine. Two of these studies evaluated the effect of antidepressive agents in rats submitted to both ligature-induced periodontitis and depression models, showing that depressive rats had greater alveolar bone loss (ABL). Only the venlafaxine study was not able to find any significant ABL reduction in the group that used this antidepressive drug. The other four studies showed statistically-significant differences, favoring the group with the antidepressant agent. Treatments that are able to modulate the brain-neuroendocrine-immune system could be used as an adjuvant to periodontal disease management. However, studies on humans and animals are scarce, limiting the conclusion of a positive effect in the present systematic review.

Impact of post-traumatic stress disorder on oral health

BACKGROUND

The stress experienced as an intense and traumatic event can increase the odds of orofacial pain, affect the biomechanics of masticatory system and compromise the periodontal health. This study was conducted to investigate the impact of post-traumatic stress disorder (PTSD) on oral health.

METHODS

A case-control study with a convenience sample was designed. Probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing, and plaque were recorded at 6 sites per tooth. A visual analog scale (VAS) was used to evaluate the pain after probing. The Research Diagnostic Criteria for Temporomandibular Disorders Axis II (RDC/TMD Axis II) and Structured Clinical Interview (DSM-IV) were also applied. The final sample comprised 38 PTSD patients and 38 controls.

RESULTS

Patients with PTSD had a higher degree of chronic pain, more depression and nonspecific physical symptoms (including and excluding pain) compared with the control group (Fisher exact test p < 0.001, and Chi-squared test, p < 0.001, < 0.001, < 0.001, respectively). Patients with PTSD also had more pain after periodontal probing compared with controls (Mann-Whitney, p = 0.037). The prevalence of sites with CAL or PPD ≥ 4, ≥ 5, ≥ 6 were not different between the groups. Age was associated with moderate periodontitis (multivariable logistic regression model, OR = 3.33, 95% CI = 1.03-10.75, p = 0.04).

LIMITATION

The severity of PTSD precluded an ample sample size.

CONCLUSIONS

Patients with PTSD presented a worse RDC/TMD Axis II profile, more pain after periodontal probing, and no difference related to periodontal clinical parameters. More studies are needed to confirm these findings.

Simvastatin modulates gingival cytokine and MMP production in a rat model of ligature-induced periodontitis

Purpose

The aim of this study was to evaluate the effect of simvastatin on the synthesis of cytokines TNF-α and IL-10 and metalloproteinase (MMPs) 2 and 9 in a rat model of ligature-induced periodontitis.

Materials and methods

Twenty Wistar rats were used, and a cotton ligature was place in a subgingival position encircling the entire cervix of the first molar of the left (ipsilateral) side of the mandible. The right (contralateral) side of the mandible had no ligature placed and was used as control. After the ligature placement, animals were randomly assigned to two experimental groups (n=10): 1) rats with ligature + vehicle (saline; 10 mL/kg; orally) and 2) rats with ligature + simvastatin (25 mg/kg; orally). After 14 days of treatment, the animals were euthanized by anesthetic overdose and the gingival tissue was removed and homogenized in appropriate buffer. MMP-2 and -9 release as well as the IL-10 and TNF-α levels were detected by enzyme-linked immunosorbent assay. Statistical comparison was performed by unpaired Student’s t-test, with p<0.05 representing significance.

Results

No differences were observed for TNF-α production between the groups (p>0.05). However, IL-10 was upregulated in simvastatin-treated animals (1.8-fold increase) in comparison with the vehicle-treated group (p<0.05). Simvastatin reduced the gingival levels of MMP-9 (64.3%) in comparison with vehicle-treated samples (p<0.05).

Conclusion

Oral treatment with simvastatin increased the release of IL-10 and reduced the MMP-9 in ligature-induced periodontitis model in rats.

Fluoxetine effects on periodontogenesis: histomorphometrical and immunohistochemical analyses in rats

Reports have indicated that serotonin plays an important role in cell migration and differentiation during the organogenesis of several tissues, including the oral types. Administration of selective serotonin reuptake inhibitor (SSRI) drugs during pregnancy could affect the delivery of serotonin to embryonic tissues altering its development.

Roles of Wnt3a and Dkk1 in experimental periodontitis

Background/purpose

Periodontitis is an inflammatory, destructive disease caused by periodontal bacteria, and its molecular mechanism remains unclear. The aims of this study are to evaluate the expressions of Wnt3a and Dkk1 in experimental periodontitis (EP) and preliminarily explore their roles in periodontal diseases.

Materials and methods

A total of 64 six-week-old male Sprague–Dawley rats were randomly divided into a normal group and an EP group. The EP group was prepared by using silk ligature combined with intraoral bacteria inoculation. To assess the periodontal inflammation and bone destruction extent, hematoxylin and eosin staining and tartrate-resistant acid phosphatase staining was performed 2 weeks, 4 weeks, and 6 weeks after the modeling, respectively, and immunohistochemistry and enzyme-linked immunosorbent assay were also performed to detect the changes of Wnt3a and Dkk1 in periodontal tissue and plasma.

Results

Wnt3a expression was significantly decreased in the EP group when compared with the normal group (P < 0.05). Meanwhile, Dkk1 expression was significantly increased in the EP group when compared with the normal group (P < 0.05).

Conclusion

The expression of Wnt3a and Dkk1 was well correlated with EP. It is suggested that Wnt3a and Dkk1 may be involved in periodontal diseases.

TNFAIP3, a negative regulator of the TLR signaling pathway, is a potential predictive biomarker of response to antidepressant treatment in major depressive disorder

Inflammation and abnormalities in Toll-like receptor (TLR) expression and activation have been linked to major depressive disorder (MDD). However, negative regulators of TLR pathways have not been previously investigated in this context. Here, we sought to investigate the association of depression severity, measured by the 17-item Hamilton Depression Rating Scale (HAMD-17), with mRNA expression levels of negative regulators of the TLR pathway, including SOCS1, TOLLIP, SIGIRR, MyD88s, NOD2 and TNFAIP3, in peripheral blood mononuclear cells (PBMCs) from 100 patients with MDD and 53 healthy controls, before and after treatment with antidepressants. Positive regulators of the TLR4 pathway, including Pellino 1, TRAF6 and IRAK1, were also investigated. Among all patients, MyD88s, and TNFAIP3 mRNAs were expressed at lower levels in PBMCs from patients with MDD. Multiple linear regression analyses revealed that TNFAIP3 mRNA expression before treatment was inversely correlated with severity of depression and effectively predicted improvement in HAMD-17 scores. Among 79 treatment-completers, only TNFAIP3 mRNA was significantly increased by treatment with antidepressants for 4 weeks. Treatment of human monocytes (THP-1) and mouse microglia (SIM-A9) cell lines with fluoxetine significantly increased TNFAIP3 mRNA expression and suppressed IL-6 levels. The suppressive effect of fluoxetine on IL-6 was attenuated by knockdown of TNFAIP3 expression. These findings suggest that both dysfunction of the negative regulatory system in patients with MDD and antidepressant treatment exert anti-inflammatory effects, at least in part through increased expression of the TNFAIP3 gene. They also indicate that modulating expression of the TNFAIP3 gene to rebalance TLR-mediated inflammatory signaling may be potential therapeutic strategy for treating MDD.

Serotonin-reuptake inhibitors act centrally to cause bone loss in mice by counteracting a local anti-resorptive effect

The use of selective serotonin-reuptake inhibitors (SSRIs) has been associated with an increased risk of bone fracture, raising concerns about their increasingly broader usage. This deleterious effect is poorly understood, and thus strategies to avoid this side effect remain elusive. We show here that fluoxetine (Flx), one of the most-prescribed SSRIs, acts on bone remodeling through two distinct mechanisms. Peripherally, Flx has anti-resorptive properties, directly impairing osteoclast differentiation and function through a serotonin-reuptake-independent mechanism that is dependent on intracellular Ca2+ levels and the transcription factor Nfatc1. With time, however, Flx also triggers a brain-serotonin-dependent rise in sympathetic output that increases bone resorption sufficiently to counteract its local anti-resorptive effect, thus leading to a net effect of impaired bone formation and bone loss. Accordingly, neutralizing this second mode of action through co-treatment with the β-blocker propranolol, while leaving the peripheral effect intact, prevents Flx-induced bone loss in mice. Hence, this study identifies a dual mode of action of SSRIs on bone remodeling and suggests a therapeutic strategy to block the deleterious effect on bone homeostasis from their chronic use.

Fluoxetine Inhibits NLRP3 Inflammasome Activation: Implication in Depression

BACKGROUND

Emerging evidence indicates that NLRP3 inflammasome-induced inflammation plays a crucial role in the pathogenesis of depression. Thus, inhibition of NLRP3 inflammasome activation may offer a therapeutic benefit in the treatment of depression. Fluoxetine, a widely used antidepressant, has been shown to have potential antiinflammatory activity, but the underlying mechanisms remain obscure.

METHODS

We used a chronic mild stress model and cultured primary macrophage/microglia to investigate the effects of fluoxetine on NLRP3 inflammasome and its underlying mechanisms.

RESULTS

We demonstrated that fluoxetine significantly suppressed NLRP3 inflammasome activation, subsequent caspase-1 cleavage, and interleukin-1β secretion in both peripheral macrophages and central microglia. We further found that fluoxetine reduced reactive oxygen species production, attenuated the phosphorylation of double-stranded RNA-dependent protein kinase, and inhibited the association of protein kinase with NLRP3. These data indicate that fluoxetine inhibits the activation of NLRP3 inflammasome via downregulating reactive oxygen species-protein kinase-NLRP3 signaling pathway. Correspondingly, in vivo data showed that fluoxetine also suppressed NLRP3 inflammasome activation in hippocampus and macrophages of chronic mild stress mice and alleviated chronic mild stress-induced depression-like behavior.

CONCLUSIONS

Our findings reveal that fluoxetine confers an antidepressant effect partly through inhibition of peripheral and central NLRP3 inflammasome activation and suggest the potential clinical use of fluoxetine in NLRP3 inflammasome-driven inflammatory diseases such as depression.

The role of macrophages in anti-inflammatory activity of antidepressant drugs

Depression is a common disease influencing patients' quality of life, whose etiology involves complex interactions of environmental, genetic and immunological factors. The latter factors include proinflammatory activation of monocytes and macrophages and increased serum levels of proinflammatory cytokines, altogether formulated as the "macrophage theory of depression". Our current review summarizes the impact of the most commonly used antidepressant drugs on the immune response with special emphasis on the role of macrophages in the clinically observed effects. The anti-inflammatory action of antidepressants mainly results from their direct interaction with immune cells and from changes in the concentration and the relations of neurotransmitters sensed by these cells. The summarized data revealed that Mφs are one of the leading cell populations involved in drug-mediated immune effects that can be observed both in subjects with depression as well as in individuals not suffering from depression. Thus, currently reviewed immunomodulatory effects of the experimental use of different antidepressant drugs suggest the possibility of utilizing them in complex therapeutic strategies dedicated to various inflammatory and immune-mediated diseases. It is worth noting that an excessive inflammatory reaction is also associated with the pathogenesis of various cardiovascular, metabolic and neuro-endocrine diseases. Thus, the inclusion of antidepressants in the complex therapy of these disorders may have beneficial effects through the enhancement of the mood of the patient and alleviation of chronic inflammation. On the other hand, presented data suggest that the influence of chronically used antidepressants on anti-microbial and anti-tumor immunity could also be taken into consideration.

Repeatedly administered antidepressant drugs modulate humoral and cellular immune response in mice through action on macrophages

Depression is associated with an altered immune response, which could be normalized by antidepressant drugs. However, little is known about the influence of antidepressants on the peripheral immune response and function of macrophages in individuals not suffering from depression. Our studies were aimed at determining the influence of antidepressant drugs on the humoral and cellular immune response in mice. Mice were treated intraperitoneally with imipramine, fluoxetine, venlafaxine, or moclobemide and contact immunized with trinitrophenyl hapten followed by elicitation and measurement of contact sensitivity by ear swelling response. Peritoneal macrophages from drug-treated mice were either pulsed with sheep erythrocytes or conjugated with trinitrophenyl and transferred into naive recipients to induce humoral or contact sensitivity response, respectively. Secretion of reactive oxygen intermediates, nitric oxide, and cytokines by macrophages from drug-treated mice was assessed, respectively, in chemiluminometry, Griess-based colorimetry and enzyme-linked immunosorbent assay, and the expression of macrophage surface markers was analyzed cytometrically. Treatment of mice with fluoxetine, venlafaxine, and moclobemide results in suppression of humoral and cell-mediated immunity with a reduction of the release of macrophage proinflammatory mediators and the expression of antigen-presentation markers. In contrast, treatment with imipramine enhanced the humoral immune response and macrophage secretory activity but slightly suppressed active contact sensitivity. Our studies demonstrated that systemically delivered antidepressant drugs modulate the peripheral humoral and cell-mediated immune responses, mostly through their action on macrophages. Imipramine was rather proinflammatory, whereas other tested drugs expressed immunosuppressive potential. Current observations may be applied to new therapeutic strategies dedicated to various disorders associated with excessive inflammation.

The effect of an inhibitor of gut serotonin (LP533401) during the induction of periodontal disease

BACKGROUND AND OBJECTIVE

LP533401 is an inhibitor of tryptophan hydroxylase 1, which regulates serotonin production in the gut. Previous work indicates that LP533401 has an anabolic effect in bone. Thus, we hypothesized that inhibition of gut serotonin production may modulate the host response in periodontal disease. In this study, we aimed to analyze the effects of LP533401 in a rat periodontitis model to evaluate the role of gut serotonin in periodontitis pathophysiology.

MATERIAL AND METHODS

Twenty-four rats were divided into three groups: treated group (T: ligature-induced periodontal disease and LP533401, 25 mg/kg/d) by gavage; ligature group (L: ligature-induced periodontal disease only); and control group (C: without ligature-induced periodontal disease). After 28 d, radiographic alveolar bone support was measured on digital radiographs, and alveolar bone volume fraction, tissue mineral density and trabeculae characteristics were quantified by microcomputed tomography in the right hemi-mandible. Left hemi-mandibles were decalcified and alveolar bone loss, attachment loss and area of collagen in the gingiva were histologically analyzed.

RESULTS

Significant difference between the L and C groups was found, confirming that periodontal disease was induced. We observed no difference between the T and L groups regarding alveolar bone destruction and area of collagen.

CONCLUSION

LP533401 (25 mg/kg/d) for 28 d does not prevent bone loss and does not modulate host response in a rat model of induced periodontal disease.

Association of Periodontitis and Subsequent Depression: A Nationwide Population-Based Study

Periodontitis is a systemic and chronic inflammatory disease associated with multiple physical conditions. Distress and depression are other problems affecting the progression of periodontitis. However, the causal relationship between depression and periodontitis has not been adequately investigated. This aim of this study was to determine the association between periodontitis and the subsequent development of depression.We identified 12,708 patients with newly diagnosed periodontitis from 2000 to 2005 and 50,832 frequency-matched individuals without periodontitis. Both groups were followed until diagnosed with depression, withdrawal from the National Health Insurance program, or the end of 2011. The association between periodontitis and depressio was analyzed using Cox proportional hazard regression models.The incidence density rate of depression was higher in the periodontitis group than in the nonperiodontitis group, with an adjusted hazard ratio of 1.73 (95% confidence interval 1.58-1.89) when adjusting for sex, age, and comorbidity. Cox models revealed that periodontitis was an independent risk factor for depression in patients, except for comorbidities of diabetes mellitus (DM), alcohol abuse, and cancer.Periodontitis may increase the risk of subsequent depression and was suggested an independent risk factor regardless of sex, age, and most comorbidities. However, DM, alcohol abuse, and cancer may prevent the development of subsequent depression because of DM treatment, the paradoxical effect of alcohol, and emotional distress to cancer, respectively. Prospective studies on the relationship between periodontitis and depression are warranted.

Effect of Fluoxetine Consumption on Orthodontic Tooth Movement in Rats

OBJECTIVES

Fluoxetine is a selective serotonin re-uptake inhibitor (SSRI) widely used for depression, bipolar disorder, anxiety and obsessive-compulsive disorder. The aim of this study was to assess the effect of fluoxetine on orthodontic tooth movement (OTM) in rats.

MATERIALS AND METHODS

Forty-five male Wistar rats were randomly divided into three groups namely the control group (no medication), saline and fluoxetine dissolved in saline. In all groups, nickel titanium closed-coil spring was used between the left maxillary central incisor and first molar to exert 60g force at 2mm activation. Radiographs were taken at one and 21 days. After 21 days, the rats were sacrificed. The distance between the first and second molar teeth, optical density of bone, periodontal ligament (PDL) width, lacuna length and depth and number of osteoclasts were measured and compared among the groups.

RESULTS

Tooth movement significantly increased in the fluoxetine group (P=0.005). No significant differences were found in osteoclast count (P=0.069). The PDL width in the mesioapical region of root was significantly different among the groups (P=0.015). Statistical analysis did not show significant differences in depth or length of lacunae in any examined part of the root (P>0.05). Bone densitometry results showed that in fluoxetine group, density of bone in all four areas (alveolar bone, hard palate, skull and mandibular bone) significantly decreased from day one to day 21 (P< 0.05).

CONCLUSION

This study indicated that fluoxetine decreased bone density, which resulted in subsequently greater tooth movement in rats; however, further studies are needed on humans.

Systemic effects of fluoxetine on the amount of tooth movement, root resorption, and alveolar bone remodeling during orthodontic force application in rat

Background:

Antidepressant drugs such as fluoxetine are of the most commonly used drugs among the public. These drugs may impact the regulation of bone cell functioning, and thus affect orthodontic tooth movement. The aim of this study was to determine the effect of fluoxetine on tooth movements during orthodontic treatment in rats.

Materials and Methods:

In this study, 30 male rats were randomly assigned into two groups and injected with fluoxetine 10 mg/kg (experimental group) and normal saline (control group) for a period of 1-month intraperitoneally 5 times/week. Then, the rats were anesthetized and a nickel-titanium closed-coil spring was placed between the left maxillary first molar and left maxillary central incisors of all samples, and then fluoxetine (experimental group) and normal saline (control group) were injected for another 3 weeks by the same method. After measuring tooth movements, rats were sacrificed, and histomorphometric analyses were conducted and the obtained data were statistically analyzed using independent t-test and the significance was set at 0.05.

Results:

Following the fluoxetine injection, the mean amount of tooth movements in the experimental group was reduced compared to the control group, which was not statistically significant (P = 0.14). There was no significant difference between the two groups regarding bone apposition rate (P = 0.83), external root resorption rate (P = 0.1), and mean number of root resorption lacunae (P = 0.16).

Conclusion:

Within the limitations of this study, systemic use of fluoxetine may cause insignificant reduction of tooth movement rate in rats; however, this subject needs more evaluations.

Downregulation of Proteinase-Activated Receptor-2, Interleukin-17, and Other Proinflammatory Genes by Subantimicrobial Doxycycline Dose in a Rat Periodontitis Model

BACKGROUND

Subantimicrobial dose doxycycline (SDD) has been used as an adjunct in periodontal treatment because of its matrix metalloproteinase inhibition properties. Although the benefits of SDD therapy, such as improvement in the parameters of periodontal probing depth and clinical attachment level, have been proven in multiple clinical studies, the comprehension of other biologic mechanisms of action on periodontitis remains poorly investigated. Therefore, this animal-model study evaluated the effects of SDD monotherapy on the expressions of the following key proinflammatory genes: proteinase-activated receptor-2 (PAR2), tumor necrosis factor (TNF)-α, interleukin (IL)-17, and IL-1β.

METHODS

Male Wistar rats were assigned randomly to the following: 1) control group: no ligature-induced periodontitis and no treatment; 2) ligature group: ligature-induced periodontitis and placebo treatment; and 3) ligature + doxycycline group: ligature-induced periodontitis and SDD treatment. After the experimental time, animals were sacrificed, and reverse transcription-polymerase chain reaction was performed to analyze the mRNA expression of IL-1β, IL-17, TNF-α, and PAR2 in gingival tissue samples. Histologic analyses were performed on the furcation region and mesial gingiva of mandibular first molars to measure periodontal bone loss and collagen content.

RESULTS

SDD administration significantly downregulated PAR2, IL-17, TNF-α, and IL-1β mRNA expressions (P <0.05). In addition, SDD treatment was accompanied by lower rates of alveolar bone loss (P <0.05) and maintenance of the amount of gingival collagen fibers.

CONCLUSION

These findings reveal new perspectives regarding SDD efficacy because it can be partially related to proinflammatory gene expression modulation, even considering PAR2 and IL-17, which has not been investigated thus far.

Effect of fluoxetine on induced tooth movement in rats

INTRODUCTION

Fluoxetine is a widely used antidepressant. Its various effects on bone mineral density are well described. The aim of this study was to evaluate the effect of fluoxetine on induced tooth movement.

METHODS

Seventy-two Wistar rats were divided into 3 groups: M (n = 24; 0.9% saline solution and induced tooth movement), FM (n = 24; fluoxetine, 10 mg/kg, and induced tooth movement), and F (n = 24; fluoxetine, 10 mg/kg only). After 30 days of daily saline solution or fluoxetine administration, an orthodontic appliance (30 cN) was used to displace the first molar mesially in groups M and FM. The animals were killed 3, 7, and 14 days after placement of the orthodontic appliances. The animals in group F did not receive induced tooth movement but were killed at the same times. We evaluated tooth movement rates, collagen neoformation rates by polarization microscopy, numbers of osteoclast by tartrate-resistant acid phosphatase, and trabecular bone modeling by microcomputed tomography of the femur.

RESULTS

The tooth movement rates were similar in groups M and FM at all studied time points (P >0.05). The rate of newly formed collagen had a reverse pattern in groups M and FM, but the difference was not statistically significant (P >0.05). There were significantly more osteoclasts in group FM than in group F on day 3 (P <0.01). The trabecular spacing was significantly larger in group F compared with group M on day 14 (P <0.05).

CONCLUSIONS

Fluoxetine did not interfere with induced tooth movement or trabecular bone in rats.

Toxicological evaluation of sediment samples spiked with human pharmaceutical products: Energy status and neuroendocrine effects in marine polychaetes Hediste diversicolor

There is a lack of studies about the ecotoxicology of pharmaceutical products on marine environment. To predict possible adverse effects of pharmaceutical products on benthic biota, polychaetes Hediste diversicolor were exposed for 14-days to pharmaceutical-spiked sediments under laboratory conditions. Carbamazepine (CBZ), ibuprofen (IBP) and propranolol (PRO) at concentrations of 500ngg(-1), 50ngg(-1), 5ngg(-1), 0.5ngg(-1) and 0.05ngg(-1), fluoxetine (FX) and 17α-ethynylestradiol (EE2) at concentrations of 100ngg(-1), 10ngg(-1), 1ngg(-1), 0.1ngg(-1) and 0.01ngg(-1), including environmental concentrations (underlined), were spiked in marine sediment samples. After the exposure, cellular energy status (total lipids content - TLP; and mitochondrial electron transport activity - MET), metabolism of monoamines (monoamine oxidase activity - MAO) and inflammation properties (cyclooxygenase activity - COX) were observed in polychaetes. CBZ increased TLP content and MET activity, and decreased MAO activity in polychaetes. IBP did not interfere on the TLP level, but on the MET and MAO activities (environmental concentrations). FX did not cause changes in the energy status. Therefore, environmental concentration diminished MAO activity. EE2 did not affect the energy status, however, MAO activity was significantly lower in polychaetes exposed to environmental concentration. PRO increased TLP level in polychaetes, but not MET activity. MAO activity was significantly lower for polychaetes exposed to environmental concentration. Except FX, all pharmaceuticals showed anti-inflammatory properties confirmed by the decrease of COX activity. Pharmaceutical products affected H. diversicolor physiology and health. As a benthic top predator, adverse effects on sea-worms can potentially culminate in ecosystem perturbations.

Exenatide and Sitagliptin Decrease Interleukin 1β, Matrix Metalloproteinase 9, and Nitric Oxide Synthase 2 Gene Expression But Does Not Reduce Alveolar Bone Loss in Rats With Periodontitis

BACKGROUND

New drugs for the treatment of diabetes, glucagon-like peptide-1 (GLP-1) receptor agonists and inhibitors of dipeptidyl peptidase-4 (DPP-4) have shown pleiotropic effects on bone metabolism and anti-inflammatory properties. The aim of this study is to evaluate the effects of exenatide (GLP-1 agonist) and sitagliptin (DPP-4 inhibitor) during periodontitis induction by ligature insertion in rats.

METHODS

Forty rats were divided into four groups: 1) animals with induced periodontitis that received exenatide (EG); 2) animals with induced periodontitis that received sitagliptin (SG); 3) animals with induced periodontitis and without drug treatment (LG); and 4) animals without induced periodontitis and without drug treatment (controls). The drugs were administered for 28 days. On the day the animals were sacrificed, blood was collected for analysis of glucose and DPP-4 levels. The gene expressions of prostaglandin-endoperoxide synthase 2, tissue inhibitor of metalloproteinase 1, Dpp4, nitric oxide synthase 2 (Nos2), interleukin 1β (Il1b), and matrix metalloproteinase 9 (Mmp9) in the gingiva; support and alveolar bone loss; connective tissue attachment; and the quantity of gingival collagen were evaluated.

RESULTS

Exenatide and sitagliptin treatments have led to a lower percentage of weight gain but did not influence glycemia. Sitagliptin reduced the serum concentration of DPP-4. Interestingly, although the gene expression profile has revealed a downregulation of Mmp9, Nos2, and Il1b in both EG and SG compared to LG, a significant protective effect was not observed on alveolar bone and collagen tissue in this model.

CONCLUSION

Regardless of the reduction of the expression of Il1b, Nos2, and Mmp9, the drugs were not effective in the stabilization or reduction of alveolar bone loss and collagen degradation in rats.

Effects of treatment with fluoxetine on mandibular development: A morphological study in rats

AIM

To verify whether the use of fluoxetine during gestation and lactation interferes in mandibular bone formation in rats.

METHODS

Twenty-four Wistar rat pups were used and distributed into four groups: CG - control of gestation; CL - control of gestation and lactation; FG - treated with fluoxetine during gestation and FL - treated with fluoxetine during gestation and lactation. At 25 days of life, after anesthesia, perfusion and decapitation, the mandibles were removed. Radiographic, histologic, histometric and polarizing microscopy analyses were performed. Statistical analysis was used considering a level of 5% significance.

RESULT

The FL group compared with its control (CL) was shown to differ statistically from the other groups as regards histometry and radiopacity, revealing a reduction in the inferior cortical thickness, reduction in number of osteocytes, with consequent reduction in radiographic bone density. There was also reduction in the number of osteoblasts in FG.

CONCLUSION

The long-term use of fluoxetine via oral route by pregnant and lactating rats modifies the mandibular bone mass.

Effect of Fluoxetine on Periodontal Status in Patients With Depression: A Cross-Sectional Observational Study

BACKGROUND

Fluoxetine, a selective serotonin reuptake inhibitor, has been reported to reduce periodontal disease severity in a rat ligature-induced periodontitis model. The objective of the present study is to investigate the influence of fluoxetine intake on periodontal parameters in patients with periodontitis with clinical depression.

METHODS

A sample of 236 patients with chronic periodontitis and clinical depression were assessed for clinical parameters of periodontal disease. Of these, 115 patients were taking fluoxetine (20 mg/day) for ≥2 months, and 121 patients were not. Participants taking fluoxetine were further analyzed for correlation between duration of drug intake and periodontal parameters.

RESULTS

All periodontal parameters, except plaque index, were significantly lower in participants taking fluoxetine (P <0.01). Partial correlation analysis, adjusted for confounders, revealed a significant and negative correlation between duration of fluoxetine intake and attachment loss (AL) (R(2) = -0.321, P <0.05). Logistic regression analysis revealed that fluoxetine intake was associated with a lower risk of having AL ≥3 (odds ratio [OR] = 0.55, 95% confidence interval [CI] = 0.31 to 0.96) and lower odds of increased bleeding on probing (BOP) percentage values (OR = 0.62, 95% CI = 0.34 to 0.97).

CONCLUSION

In this observational study, use of fluoxetine was associated with lower BOP percentages and reduced AL.

Paroxetine differentially modulates LPS-induced TNFα and IL-6 production in mouse macrophages

Paroxetine is a selective serotonin reuptake inhibitor (SSRI) that is clinically used for the treatment of depression in human patients. Because of recent reports on the role of serotonin in modulating inflammation and the link between inflammation and depression, we sought to test the effect of paroxetine directly on macrophage response to an inflammatory stimulus. Lipopolysaccharide (LPS) treatment of mouse macrophages significantly enhanced TNFα and IL-6 production. Paroxetine treatment of macrophages, however, significantly inhibited LPS-induced IL-6 production. In contrast, paroxetine enhanced LPS-induced TNFα production in macrophages. These effects of paroxetine were mimicked by fluoxetine, another SSRI. To determine if the effects of paroxetine are mediated via modulation of the 5-HT system, we treated macrophages with 5-HT or 5-HT receptor antagonist (LY215840) in the presence of LPS and/or paroxetine. 5-HT treatment by itself did not affect LPS-induced cytokine production. LY215840, however, reversed paroxetine's effect on LPS-induced TNFα production but not IL-6. To understand the signaling mechanisms, we examined paroxetine's effect on MAPK and NFκB pathways. While paroxetine inhibited LPS-induced IκBα phosphorylation, MAPK pathways were mostly unaffected. Together these data demonstrate that paroxetine has critical but differential effects on IL-6 and TNFα production in macrophages and that it likely regulates these cytokines via distinct mechanisms.