The effect of TNF-alpha blockers on psychometric measures in ankylosing spondylitis patients: a preliminary observation

The Efficacy and Safety of Biologics in Treating Ankylosing Spondylitis and Their Impact on Quality of Life and Comorbidities: A Literature Review

Ankylosing spondylitis (AS) is a chronic inflammatory arthritis that affects the axial skeleton, causing intense pain, progressive joint destruction, and a gradual reduction in physical function. Additionally, AS can result in extra-musculoskeletal manifestations including inflammatory bowel disease (IBD), psoriasis, and acute anterior uveitis (AAU) affecting patients' quality of life (QoL). Furthermore, AS association with neurological and cardiovascular events has been documented. With the advent of biologics, treating AS has dramatically changed due to their high efficacy and tolerable safety. Nevertheless, there are differences in traits, including rapidity of onset, long-term efficacy, safety profile, and influence on comorbidities. A better understanding of such traits enables clinicians to make the best decision for each patient, increasing persistence, extending medication survival, enhancing patient satisfaction, and reducing the disease effect of AS. A review of the literature published in English in PubMed and Google Scholar databases from 2010 to 2023 was conducted. All relevant results fitting the scope of the topic were included. In this article, we emphasize biologics' efficacy and safety profile in patients with AS. In addition, we discuss the impact of biologics on comorbidities and health-related quality of life (HRQoL).

SARS-CoV-2 Psychiatric Sequelae: A Review of Neuroendocrine Mechanisms and Therapeutic Strategies

From the earliest days of the coronavirus disease 2019 (COVID-19) pandemic, there have been reports of significant neurological and psychological symptoms following Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. This narrative review is designed to examine the potential psychoneuroendocrine pathogenic mechanisms by which SARS-CoV-2 elicits psychiatric sequelae as well as to posit potential pharmacologic strategies to address and reverse these pathologies. Following a brief overview of neurological and psychological sequelae from previous viral pandemics, we address mechanisms by which SARS-CoV-2 could enter or otherwise elicit changes in the CNS. We then examine the hypothesis that COVID-19-induced psychiatric disorders result from challenges to the neuroendocrine system, in particular the hypothalamic-pituitary-adrenal stress axis and monoamine synthesis, physiological mechanisms that are only further enhanced by the pandemic-induced social environment of fear, isolation, and socioeconomic pressure. Finally, we evaluate several FDA-approved therapeutics in the context of COVID-19-induced psychoneuroendocrine disorders.

Effects of long-term infliximab and tocilizumab treatment on anxiety-like behavior and cognitive function in naive rats

BACKGROUND

Circulating cytokines have been proposed to be implicated in the development of mood disorders and cognitive impairment. This study aims to examine the effect of chronic treatment with infliximab, a tumor necrosis factor-alpha (TNF-alpha) inhibitor, and tocilizumab, an antibody against interleukin-6 (IL-6) receptor on anxiety-like behavior and cognitive function.

METHODS

Twenty-eight male, Wistar rats were randomly allocated into negative control, vehicle, infliximab and tocilizumab groups. After 8 weeks of intraperitoneal drug administration, rats performed the elevated-plus maze, the elevated-zero maze, the olfactory social memory and the passive avoidance tests. Brain sections at the level of the hippocampus, the amygdala and the prefrontal cortex were histologically examined. Finally, hippocampal and amygdaloid brain-derived neurotrophic factor (BDNF) expression was determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR).

RESULTS

Infliximab group exhibited a significantly higher number of entries and time spent into the open arms of the mazes, showing a lower level of anxiety. In the olfactory social memory test, tocilizumab significantly increased the ratio of interaction. Both infliximab- and tocilizumab-treated animals had a significantly lower latency time in the passive avoidance test that suggests an improved memory. Histological examination revealed similar morphology and neuronal density between groups. BDNF expression levels were significantly increased in the groups receiving anti-cytokine treatment.

CONCLUSIONS

Our findings suggest that long-term peripheral TNF-alpha and IL-6 inhibition improves anxiety and cognitive function in rats and leads to an increased BDNF expression in the brain.

Benefit of Biological Drugs for Quality of Life in Patients with Ankylosing Spondylitis: A Systematic Review and Meta-Analysis of Clinical Trials

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease involving the axial skeleton, peripheral joints, and extra-articular manifestations like psoriasis, inflammatory bowel disease, or uveitis. A deterioration of quality of life (QoL) affects the disease management and therapeutic decision-making. This meta-analysis focused on the influence of biological drugs on the QoL in SA compared to the effects of other therapeutic modalities. We searched the databases of MedLine, Academic Search Ultimate, CINAHL Complete, and Health Source - Nursing/Academic Edition for articles related to AS treatment using the terms "ankylosing spondylitis" OR "rheumatoid spondylitis" OR "spondylitis" AND "quality of life" OR "patient-reported outcomes" OR "well-being" OR "health-related quality of life" OR "biological treatment". The search came up with 10 English-language articles published between 2010 and 2020. Patients were evaluated with the following indexes and questionnaires: Assessment of Spondyloarthritis International Society (ASAS), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Quality of Life (ASQoL), 36-Item Short-Form Health Survey (SF-36), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), and the Bath Ankylosing Spondylitis Functional Index (BASFI), and Bath Ankylosing Spondylitis Functional (BASFI) Indexes. We found that the QoL, assessed with the ASQoL, improved significantly better in patients treated with biological drugs when compared to those treated with other standard therapies or placebo at a 4-month follow-up. However, improvements in other disease characteristics could not be differentiated based on the therapy modality. The finding that biological drugs are superior in improving the QoL should strengthen the recommendations for their use in patients with AS.

Infliximab treatment reduces depressive symptoms in patients with ankylosing spondylitis: an ancillary study to a randomized controlled trial (ASSERT)

Background

Patients with ankylosing spondylitis (AS) are at increased risk of depression. This increased risk has been hypothesized to be solely secondary due to AS-related symptoms, or additionally due to a common inflammatory pathway. From a clinical perspective, it is important to know whether treatment with tumor necrosis factor alpha inhibitors reduces depressive symptoms, while from a pathophysiological point of view, it would be insightful to understand whether such an effect would be a direct result of reduced inflammation, the result of reduced AS-related symptoms, or both. The objective of this study was to evaluate the effect of infliximab on depressive symptoms in patients with AS in a randomized-controlled trial setting.

Methods

Data were retrieved from a subgroup of patients from the AS Study for the Evaluation of Recombinant Infliximab Therapy (ASSERT). Patients were randomly allocated to infliximab (n = 16) or placebo (n = 7) until week 24, after which all received infliximab until week 54. Associations between treatment group and depressive symptoms, measured with the Center for Epidemiological Studies Depression scale (CES-D, range 0–60 (best-worst)) at baseline and over time, were explored with generalized estimating equations (GEE).

Results

Mean CES-D score at baseline was 15.5 (SD 9.3) in the infliximab group and 17.3 (SD 5.7) in the placebo group. Twelve patients (52%) had a CES-D score > 16, suggestive for clinical depression. After 24 weeks, mean CES-D had decreased to 9.5 (SD 11.4) in the infliximab group, but was 18.0 (SD 6.9) in the placebo group. GEE revealed larger improvements in depressive symptoms (B = − 6.63, 95%CI − 13.35 to 0.09) and odds of possible depression (OR = 0.02, 95%CI 0.00 to 0.72) in the infliximab group, compared to the placebo group. Both associations largely disappeared when adjusted for self-reported disease activity and/or physical function. Additional adjustment for C-reactive protein (CRP) did not change results.

Conclusions

Depressive symptoms are common in patients with AS and active disease. Infliximab improves these depressive symptoms in AS when compared to placebo by improving disease symptoms. We did not find an indication for a direct link between CRP-mediated inflammation and depressive symptoms.

Trial registration

Trial registration (ASSERT): NCT00207701. Registered on September 21, 2005 (retrospectively registered).

Longitudinal associations between depressive symptoms and clinical factors in ankylosing spondylitis patients: analysis from an observational cohort

OBJECTIVES

Although cross-sectional studies have shown that ankylosing spondylitis-specific factors correlate with depressive symptom severity, the association of these factors over time is unresolved. We examined the demographic and clinical factors associated with longitudinal depressive symptom severity in AS patients.

METHODS

We analyzed sociodemographic, clinical, behavioral and medication data from 991 patients from the Prospective Study of Outcomes in Ankylosing spondylitis cohort, and measured depression severity with the Center for Epidemiological Studies Depression (CES-D) Scale administered at approximately 6-month visit intervals. Multivariable longitudinal negative binomial regression models were conducted using generalized estimating equation modeling to assess the demographic, clinical, and medication-related factors associated with depression severity by CES-D scores over time.

RESULTS

The median baseline CES-D score (possible range 0-60) was 10.0 (interquartile range = 5, 17). In longitudinal multivariable analyses, higher CES-D scores were associated with longitudinal smoking, greater functional impairment, greater disease activity, self-reported depression, and poor global health scores. Marital status (e.g., being married) was associated with lower CES-D. Adjusted mean CES-D scores in our model decreased over time, with a significant interaction between time and gender observed.

CONCLUSION

This study identified longitudinal clinical factors such as greater disease activity, greater functional impairment, and poor global health to be associated with longitudinal depression severity. These factors are potentially modifiable and may help manage depressive symptoms in AS.

Fatigue and contributing factors in Chinese patients with ankylosing spondylitis

OBJECTIVES

Fatigue is a common symptom in patients with ankylosing spondylitis (AS). However, fatigue of AS patients has not been well elucidated in China. This study aimed to evaluate the predictors of fatigue and the effects of fatigue on health-related quality of life among patients with AS.

METHOD

A total of 150 AS patients were involved in the study. A series of questionnaires included the following: Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Metrology Index (BASMI), Bath Ankylosing Spondylitis Functional Index (BASFI), the 10-cm Visual Analog Scale (VAS), the Self-Rating Anxiety Scale (SAS), the Self-Rating Depression Scale (SDS), the Pittsburgh Sleep Quality Index (PSQI), the Health Assessment Questionnaire-Disability Index (HAQ-DI), the Short Form 36 Health Survey (SF-36), and the Fatigue Severity Scale (FSS). Independent samples t test, Mann-Whitney U test, chi-square analysis, Pearson/Spearman correlation, and binary logistic regression were used to analyze the data.

RESULTS

The results demonstrated that 48.7% individuals with AS suffered from fatigue. Binary logistic regression indicated that waist-to-hip ratio, BASDAI, and sleep disturbance were independent predictors of fatigue in AS patients. Meanwhile, severe fatigue led to lower quality of life.

CONCLUSION

These findings suggested that medical personnel should pay more attention to AS patients with fatigue and take effective measures to relieve fatigue. Key Points • Incidence of fatigue in AS patients is 48.7% according to this cross-sectional study. • The occurrence of fatigue was associated with higher WHR, higher BASDAI, and sleep disturbance. • We also found that the occurrence of fatigue significantly reduced the quality of life in AS patients both physically and psychologically.

Use of antidepressants and benzodiazepine-related hypnotics before and after initiation of TNF-α inhibitors or non-biological systemic treatment in patients with rheumatoid arthritis, psoriatic arthritis or ankylosing spondylitis

Background

Rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS) are autoimmune disorders associated with an increased risk for depression, anxiety and sleeping problems. The objective of this study was to analyze use of antidepressants and benzodiazepine-related hypnotics (BRH) in Sweden before and after first time treatment with anti-TNF and non-biological systemic (NBS) treatments among patients with the above diagnoses, and to correlate such use with that of randomly selected population controls.

Methods

Patients and dispensed drugs were identified in nationwide Swedish healthcare registers. Proportions of subjects filling prescriptions of antidepressants and BRH from 2 years before start of treatment (index-date), and 2 years after index date were assessed. Using the period -6 months to index-date as reference, prevalence rate ratios were computed for 6 months' intervals before and after index. For up to ten randomly selected population controls per patient, the same measures were calculated.

Results

A total of 6256 patients started anti-TNF treatment, and 13,241 NBS treatment. The mean age at index was 52.0 for the anti-TNF group and 56.1 for NBS. Use of antidepressants and BRH was similar in both treatment groups (10.4-12.8%), significantly more common than in the controls (6.6 to 7.6%). For all patients, proportions filling prescriptions for antidepressants and BRH decreased directly or soon after the index; no such changes were seen in the controls, who all showed a slow but steady increase in use over time. Starters of anti-TNF treatment did not show clearer decreases in use of psychotropics than those initiating NBS.

Conclusions

Decreased rates of dispensed psychotropic drugs after the time of anti-TNF and NBS treatment initiation were seen among patients with autoimmune disorders but not population controls. This may correspond to treatment effects of anti-TNF and NBS also on psychiatric symptoms among these patients.

Depression/anxiety symptoms in axial spondyloarthritis and psoriatic arthritis patients in Serbia: a pilot study

To assess prevalence and change of depression/anxiety symptoms in spondyloarthritis patients and feasibility of depression/anxiety questionnaires. 43 Patients with axial spondyloarthritis (axSpA) and 27 patients with psoriatic arthritis (PsA) were consecutively recruited. There were 34 patients on biologics and 36 patients on nonbiologics. Patients were not previously treated for depression. The demographic variables, pain, patient global assessment, laboratory, clinical findings, diseases activity scores, Beck Depression Inventory (BDI) and Depression Anxiety and Stress Scale-short version (DASS-21) were collected. The study visits were at the beginning, after 1 month, after 3 and after 6 months. In axSpA and PsA patients on biologics, BDI and DASS-21 were significantly lower compared to nonbiologics group during time. The axSpA patients on biologics had significantly lower BDI and depression severity by BDI at each time point and lower DASS-21 after 1, 3 and 6 months. BDI in PsA patients who received biological therapy was significantly lower after 3 and 6 months. In biologics groups, BDI significantly decreased after 3 months in axSpA patients and after 1 month in PsA patients. In axSpA patients, there was a medium correlation between BDI and axial pain, patient global assessment and disease activity scores. The biological therapy significantly affected the depression/anxiety symptoms in axSpA and PsA during time. BDI moderately correlated with pain and disease activity in axSpA. BDI and DASS-21 are easy to use in daily practice.

Brain Kynurenine and BH4 Pathways: Relevance to the Pathophysiology and Treatment of Inflammation-Driven Depressive Symptoms

The prevalence of depressive disorders is growing worldwide, notably due to stagnation in the development of drugs with greater antidepressant efficacy, the continuous large proportion of patients who do not respond to conventional antidepressants, and the increasing rate of chronic medical conditions associated with an increased vulnerability to depressive comorbidities. Accordingly, better knowledge on the pathophysiology of depression and mechanisms underlying depressive comorbidities in chronic medical conditions appears urgently needed, in order to help in the development of targeted therapeutic strategies. In this review, we present evidence pointing to inflammatory processes as key players in the pathophysiology and treatment of depressive symptoms. In particular, we report preclinical and clinical findings showing that inflammation-driven alterations in specific metabolic pathways, namely kynurenine and tetrahydrobiopterin (BH4) pathways, leads to substantial alterations in the metabolism of serotonin, glutamate and dopamine that are likely to contribute to the development of key depressive symptom dimensions. Accordingly, anti-inflammatory interventions targeting kynurenine and BH4 pathways may be effective as novel treatment or as adjuvants of conventional medications rather directed to monoamines, notably when depressive symptomatology and inflammation are comorbid in treated patients. This notion is discussed in the light of recent findings illustrating the tight interactions between known antidepressant drugs and inflammatory processes, as well as their therapeutic implications. Altogether, this review provides valuable findings for moving toward more adapted and personalized therapeutic strategies to treat inflammation-related depressive symptoms.

Patients' concerns regarding biological agents in rheumatology

OBJECTIVE

The potential side effects of biological agents may increase the anxiety levels of patients and influence not only their desire to use these therapies but also their concordance to treatment. This study aimed to determine the level and prevalence of drug-related concern in patients treated with biological agents and to acquire additional information regarding the related causes.

MATERIALS AND METHODS

A total of 1134 patients who were using biological agents for at least 3 months with a diagnosis of rheumatic diseases were enrolled. General anxiety levels were evaluated using the State-Trait Anxiety Inventory (STAI).

RESULTS

The most common cause for drug-related concerns was the potential side effects of the drugs (59.5%). Among the potential side effects, cancer risk was the most common cause for concern (40.1%), followed by the risk of tuberculosis activation (30.7%). Anxiety levels were higher in patients who experienced side effects than in other patients, and this difference was statistically significant (P < 0.05). STAI trait and state scores were moderately correlated with anxiety levels related to the drug (P < 0.001).

CONCLUSION

Anxiety related to biological agents may significantly affect the patients' anxiety levels. Awareness regarding the patients' concerns and expectations related to the drug is important to ensure drug adherence and concordance to treatment.

Depression and anxiety in axial spondyloarthritis

Axial spondyloarthritis (SpA) is a spectrum of chronic inflammatory rheumatologic diseases commonly presenting with symptoms of inflammatory back pain, peripheral joint pain, and fatigue. When compared to the general population, patients with SpA have higher prevalence of depression and anxiety symptoms. Poor psychological status is associated with worse disease activity, poorer functional status, poor treatment adherence, and unhealthy lifestyle choices such as cigarette smoking. The Chinese-bilingual Hospital Anxiety and Depression Scale (HADS) is a validated tool to screen depression and anxiety in patients with axial SpA. The cytokine theory of depression may explain emerging evidence on the mutually beneficial effects of antidepressants on disease outcomes and anti-tumor necrosis factor α (TNFα) therapy on psychological status.

The Involvement of TNF-α in Cognitive Dysfunction Associated with Major Depressive Disorder: An Opportunity for Domain Specific Treatments

Major depressive disorder is a highly prevalent, chronic and recurring disorder, associated with substantial impairment in cognitive and interpersonal functions. Accumulating evidence suggests that inflammatory processes play an important role in the etio-pathogenesis, phenomenology, comorbidity and treatment of MDD. Suboptimal remission rates and the persistence of cognitive deficits contribute to functional impairment in MDD inviting the need for the development of mechanistically novel and domain specific treatment approaches. The MEDLINE/ Pubmed database was searched from inception to February, 9^th, 2014 with combinations of the following search terms: ‘TNF-alpha’, ‘depression’, ‘infliximab’, ‘etanercept’, ‘adalimumab’, ‘golimumab’and ‘certolizumab’. Preclinical and clinical evidence linking TNF-α to MDD pathophysiology were reviewed as well as the current status of TNF-α modulators as novel agents for the treatment of MDD. Experimental models and clinical studies provide encouraging preliminary evidence for the efficacy of TNF-α antagonists in mitigating depressive symptoms and improving cognitive deficits. Further studies are warranted to confirm these data in larger randomized controlled trials in primary psychiatric populations. Translational research provides a promising perspective that may aid the development and/or repurposing of mechanism-based treatments for depressive symptoms and cognitive impairment in MDD.

Pathogenetic and Therapeutic Applications of Tumor Necrosis Factor-α (TNF-α) in Major Depressive Disorder: A Systematic Review

Major depressive disorder (MDD) is characterized by mood, vegetative, cognitive, and even psychotic symptoms and signs that can cause substantial impairments in quality of life and functioning. Up to now, the exact pathogenesis of MDD remains poorly understood. Recent research has begun to reveal that the pro-inflammatory cytokines, particularly, tumor necrosis factor-α (TNF-α), play an integral role in the pathophysiology of depressive disorders and the mechanism of antidepressant treatment. On the base of several observations: it is found that subsets of MDD patients have enhanced plasma levels TNF-α; antidepressant treatments had linked with the decline of TNF-α; central administration of TNF-α gives rise to sickness behavior which shares features with depression; and a blockade of it can ameliorate depressive symptomatology in animal models and clinical trials. In this review article, we focus on recent evidence linking TNF-α and MDD looking at data from animal and clinical studies, illustrating the pathophysiological role, susceptibility and its therapeutic application in depression. We conclude by discussing future directions for research, in particular the opportunities for the development of novel therapeutics that target TNF-α. This will be very important for designing preventative strategies and for the identification of new drug targets and preventative strategies.

Comparative Study of Infliximab Therapy and Methotrexate Monotherapy to Improve the Clinical Effect in Rheumatoid Arthritis Patients

Objective We examined whether infliximab (IFX) therapy was more effective than methotrexate (MTX) monotherapy to achieve an improvement in depressive states in Rheumatoid Arthritis (RA) patients. Methods We examined 152 RA patients (72 IFX patients and 80 MTX patients). We conducted an open-label cohort study to evaluate the disease activity of RA (Simplified Disease Activity Index; SDAI), depressive states (Hamilton Rating Scale for Depression; HAM-D), Activity of Daily Living (ADL) (modified Health Assessment Questionnaire; mHAQ) and Quality of Life (QOL) [Short Form (SF)-36] in patients before and 6 months after receiving therapy. The HAM-D, SDAI, mHAQ and SF-36 scores after 6 months of therapy were measured as the outcomes. Results We analyzed 60 IFX patients and 53 MTX patients. The HAM-D scores significantly improved in both groups (p<0.001), but there was no significant difference in the effectiveness between the IFX and MTX therapies (p=0.792). The SDAI scores significantly improved in both groups after therapy (p<0.001), and IFX therapy was more effective than MTX therapy (p=0.004). The mHAQ and HAM-D scores also improved significantly in both groups after therapy (p<0.001), but no significant difference in the effectiveness between the IFX and MTX therapies was observed (p=0.272, 0.792). The scores of all 8 items of the SF-36 improved in both groups after therapy, but IFX therapy was more effective than MTX therapy in only 4 of the 8 items (p<0.05). Conclusion Both IFX and MTX therapy improved the clinical efficacy, ADL, QOL and depressive states. However, no significant differences regarding an improvement in the depressive states and ADL were observed between IFX therapy and MTX monotherapy.

Tumour necrosis factor-α inhibitor therapy in chronic physical illness: A systematic review and meta-analysis of the effect on depression and anxiety

OBJECTIVE

Depression is more common among individuals with chronic physical illness than in the general population. New treatments for severe and chronic inflammatory conditions which inhibit tumour necrosis factor alpha (TNF-α), a pro-inflammatory cytokine, may be able to shed some light on the role of inflammatory mediators in depression. This systematic review and meta-analysis of randomised controlled trials determined the effects of TNF-α inhibitor therapy on depression and anxiety in people with chronic physical illness.

METHODS

Seven databases were searched from inception to January 2014: AMED, Central, Cochrane Database of Systematic Reviews, CINAHL, Embase, MEDLINE, and PsycINFO. Articles were screened for inclusion independently by two reviewers. Data extraction and appraisal were conducted by one reviewer and checked by a second. Random-effects meta-analyses were performed.

RESULTS

Six randomised controlled trials (reported in seven articles) met eligibility criteria and were included in the final review. In total 2540 participants were enrolled across the trials, with participants presenting with rheumatoid arthritis (n=3 trials), psoriasis (n=2) or ankylosing spondylitis (n=1). Meta-analyses, using standardised mean differences, showed evidence of small reductions in depression (-0.24; 95% CI -0.33 to -0.14; p<0.001), and anxiety (-0.17; 95% CI -0.31 to -0.02; p=0.02).

CONCLUSION

TNF-α inhibitor therapy reduces depression in people with chronic disease though the effects are small. Whilst this is consistent with inflammation contributing to the development of depression, further studies investigating a more detailed timeline of changes in depression, inflammatory biomarkers and disease activity status are required.

Tumor necrosis factor alpha induces a serotonin dependent early increase in ciliary beat frequency and epithelial transport velocity in murine tracheae

The tracheal epithelium prevents via its highly effective clearance mechanism the contamination of the lower airways by pathogens. This mechanism is driven by ciliary bearing cells which are not only in contact with the gas phase; in addition they are also influenced by inflammatory mediators. These mediators can alter the protective function of the epithelium. Since the pro-inflammatoric cytokine tumor necrosis factor-α (TNF-α) plays a pivotal role within the inflammatory cascade, we investigated its effect onto the tracheal epithelium measured by its ciliary beat frequency and the particle transport velocity. In organ explant experiments the ciliary beat frequency and the particle transport velocity were measured under the application of TNF-α using tracheae from male C57BL6J mice. We observed a dose dependent TNF-α induced increase of both particle transport velocity and ciliary beat frequency. Knock out mice experiments made evident that the increase was depended on the expression of tumor necrosis factor receptor 1 (TNF-R1). The increases in ciliary beat frequency as well as the accelerated particle transport velocity were either inhibited by the unspecific serotonin antagonist methysergide or by cyproheptadine a specific 5-HT2 receptor antagonist. Thus, acetylcholine antagonists or nitric oxide synthase (NOS) inhibitors failed to inhibit the TNF-α induced activation. In conclusion, TNF-α may play a pivotal role in the protection of lower airways by inducing ciliary activity and increase in particle transport velocity via TNF-R1 and 5-HT2 receptor.