Immunologic basis and management of steroid-resistant asthma

The Anti-Inflammatory Effects of Invigorating Kidney and Supplementing Qi Chinese Herbal Formulae in Asthma Patients

BACKGROUND

The theories of Shen-reinforcement and Qi-supplementation are important in asthma treatment based on traditional Chinese medicine theories. Early studies suggested that Invigorating Kidney and Supplementing Qi herbal formulae, Bu Shen Fang Chuan (BSFC) and Bu Shen Yi Qi (BSYQ), conveyed promising results in asthma treatment. However, the efficacy and safety of the formulae need to be further investigated by a randomized double-blind clinical trial.

METHODS

328 eligible patients were randomly sent to BSFC, BSYQ, and placebo group. The two formulae were received as add-on therapy. The primary endpoints were rate of asthma exacerbation and Hamilton Rating Scale for Depression (HAM-D) score. The secondary endpoints included HPA axis function and inflammatory cytokine production profile. All indexes were measured before and after treatment.

RESULTS

The primary endpoints were not improved in both groups; however, the depression levels of subgroup patients with HAM-D score > 5 were improved in BSFC group. HPA axis functions and inflammatory cytokines level were also improved by two formulae. The incidences of adverse events were similar among groups.

CONCLUSIONS

The two formulae had multiple advantage effects on neuroendocrine-immune system. They are worth used as a replacement therapy in asthma.

TRIAL REGISTRATION

This trial is registered with clinical trial number ChiCTR-PRC-09000529.

Psychiatric Factors in Asthma

Emotional factors are an obstacle in the diagnosis and management of asthma. This review discusses three problem patterns: negative emotions in relatively normal patients with asthma; patients presenting possible functional symptoms and; patients presenting asthma in conjunction with psychiatric deviations. Negative emotions influence the symptoms and management of asthma, even in relatively normal patients. Psychogenic symptoms appear normal, but culminate in functional symptoms in a minority of patients. Diagnosing and treating asthma in patients with comorbid asthma and psychiatric symptoms is very difficult. On the one hand, treating asthma may often be just treating the emotions. On the other hand, negative emotions make the treatment of asthma guesswork. Physicians should estimate emotional influences in their patients' symptoms for an optimal evaluation of medication efficacy. Assessment and analysis of emotional factors surrounding exacerbations seems essential, e.g. emotional precipitants of asthma and asthma-evoked negative emotions. Moreover, patients should be informed about stress-induced breathlessness and the consequences of overuse of bronchodilators. When patients present with atypical symptoms, or do not properly respond to asthma medication, functional symptoms should be suspected. Psychiatric analysis may often lead to the conclusion that symptoms have a functional basis. In patients with comorbid asthma and anxiety disorders, asthma should be the focus for treatment since difficult-to-control asthma often causes anxiety problems in the first place. Moreover, panic-like symptoms in asthma are often related to sudden onset asthma exacerbations. However, in patients with comorbid asthma and depression, depression should become the focus of treatment. The reason is that optimal treatment of depressive asthmatics is probably impossible. Special issues include specific problems with children, compliance problems, and physicians' dilemmas regarding the simultaneous treatment of asthma and psychiatric symptoms.

A review of candidate pathways underlying the association between asthma and major depressive disorder

OBJECTIVE

To consider the mechanisms that may link asthma and major depressive disorder (MDD). Asthma and MDD co-occur at higher rates than expected, but whether this reflects shared underlying pathophysiological mechanisms is not known.

METHODS

A review of the epidemiological data linking asthma and MDD was conducted and the possible biological mechanisms that could account for the high rate of this comorbidity were reviewed.

RESULTS

MDD occurs in almost half of patients with asthma assessed in tertiary care centers. Dysregulation of the hypothalamic pituitary adrenal axis may predispose people to both MDD and asthma, and similar alterations in the immune, autonomic nervous, and other key systems are apparent and may contribute to this increased risk of co-occurrence.

CONCLUSIONS

High rates of MDD in asthma may result from the stress of chronic illness, the medications used to treat it, or a combination of the two. The high level of co-occurrence may also reflect dysregulation of certain stress-sensitive biological processes that contribute to the pathophysiology of both conditions.

Patients with multiple sclerosis resisted to glucocorticoid therapy: abnormal expression of heat-shock protein 90 in glucocorticoid receptor complex

OBJECTIVE

The majority of patients with multiple sclerosis (MS) respond favorably to glucocorticoids (GS) for their relapse treatment (steroid-sensitive multiple sclerosis). Unfortunately, a small subset of patients with multiple-sclerosis fails to adequately respond even to high dose of GS (steroid-resistant multiple sclerosis). Mechanism of GS therapeutic unresponsiveness is not resolved.

METHODS

Transcripts for glucocorticoid receptor (GR) was assessed in peripheral blood mononuclear cells by real-time polymerase chain reaction in patients with steroid-sensitive and steroid-resistant multiple sclerosis. GR expression was assessed by Western blotting. The amount of heat-shock protein 90 (hsp90) in GR cytoplasmic complex was assessed by immunoprecipitation. Hsp90 was shown to stabilize the GR complex, to prevent its translocation to nucleus, and to inhibit GR transcription.

RESULTS

Peripheral blood mononuclear cells of steroid-resistant multiple sclerosis transcripts for all three isoforms of GR, alpha, beta, and gamma, were reduced by about two-folds compared with patients with steroid-sensitive multiple sclerosis. We have not found an increase in the beta and gamma transcripts of GR, which might serve as a dominant negative mutants, over GR alpha in steroid-resistant multiple sclerosis. The amount of hsp90 in the GR complex in cytoplasm was significantly higher in steroid-resistant multiple sclerosis compared with steroid-sensitive multiple sclerosis.

CONCLUSIONS

Molecular mechanism of GS unresponsiveness in some patients with multiple sclerosis might be related to increased presence of hsp90 in the GR cytoplasmic complex, leading to the inhibition of GR translocation to nucleus and reduction in its transcription.

Psychological factors in asthma

Asthma has long been considered a condition in which psychological factors have a role. As in many illnesses, psychological variables may affect outcome in asthma via their effects on treatment adherence and symptom reporting. Emerging evidence suggests that the relation between asthma and psychological factors may be more complex than that, however. Central cognitive processes may influence not only the interpretation of asthma symptoms but also the manifestation of measurable changes in immune and physiologic markers of asthma. Furthermore, asthma and major depressive disorder share several risk factors and have similar patterns of dysregulation in key biologic systems, including the neuroendocrine stress response, cytokines, and neuropeptides. Despite the evidence that depression is common in people with asthma and exerts a negative impact on outcome, few treatment studies have examined whether improving symptoms of depression do, in fact, result in better control of asthma symptoms or improved quality of life in patients with asthma.

Corticosteroids (inhaled and/or intranasal) in the treatment of respiratory allergy in children: safety vs. efficacy

BACKGROUND

Topical administration of Corticosteroids (CS) can reduce the total dose of CS required to treat the patient and minimize side effects. Topical CS is extremely effective and has an excellent safety profile. Nonetheless, care must be taken when multiple sites such as lungs, nose and skin are being treated. CS mechanisms of action on the inflammatory process are complex. The aim of this study is to review such mechanisms and the adverse events secondary to it.

METHODS

Review English database (Embase, PubMed, Scielo) searching words: CS, adverse events, inhaled CS, intranasal CS, and children.

RESULTS

There is a classic mechanism involving a genomic effect of CS and a non-genomic effect, independently of gene transcription process. This mechanism acts by reducing mucosal blood flow in the asthmatic airways. Second-generation topical CS is the treatment of choice in allergic diseases control because of their good anti-inflammatory activity, poor absorption and first-pass hepatic metabolism. When comparing different CS, it is important to compare therapeutically equivalent doses. Although topical CS reduces systemic side effects, local and even systemic side effects can occur. Many factors affect the amount of drug that reaches the lung, including inhaler technique and inhaler type, fine particle dose and particle distribution.

CONCLUSION

Most patients with allergic diseases respond to CS treatment, but there is a small subset of them whose response is unsatisfactory even with high doses of CS. They are classified as corticosteroid-resistant asthmatics. Pro-inflammatory cytokines appear to up regulate the expression of GRb that has been associated with CS resistance.

CMV Colitis Mimicking Recurrent Inflammatory Bowel Disease: Report of Three Cases

The association between cytomegalovirus infection and inflammatory bowel disease challenges both the clinician and the pathologist to establish the correct diagnosis and to prescribe the most appropriate form of therapy. To understand this association the authors report three patients who presented with signs and symptoms mimicking reactivated inflammatory bowel disease who responded poorly to aggressive treatment of inflammatory bowel disease. Microscopic examination, in all three cases revealed numerous nuclear and cytoplasmic viral inclusions, as demonstrated by cytomegalovirus immunohistochemistry, as well as histologic findings consistent with inflammatory bowel disease (ulcerative colitis and/or Crohn's disease). Because the clinical pathologic features of cytomegalovirus colitis and inflammatory bowel disease often overlap, and because of the possible coexistence of cytomegalovirus colitis with idiopathic colitis, the possibility of cytomegalovirus infection should be always considered, so that the most appropriate therapy can be instituted for these patients.

Glucocorticoid resistance syndrome: A diagnostic and therapeutic approach

In the past decades, several cases of the syndrome of generalized glucocorticoid (GC) resistance have been reported. This familial disease is characterized by reduced cortisol effects, due to a GC receptor (GR) defect, which is compensated by hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. As a consequence, patients present with signs of adrenal overproduction of mineralocorticoids (hypertension and hypokalaemic alkalosis) and, in females, of androgens (hirsutism, male pattern of baldness, menstrual irregularities). In a few kindreds the underlying molecular basis has been revealed--e.g. mutations in the gene coding for the GR--but in a substantial number of patients the cause of GC resistance has not yet been elucidated. In this chapter we also discuss some other determinants which can lead to GC resistance. Diagnosis of generalized GC resistance can be difficult. This review highlights the diagnostic process and therapeutic options for treating patients with this disease.

Update on glucocorticoid action and resistance

Extensive development of inhaled and oral glucocorticoids has resulted in highly potent molecules that have been optimized to target activity to the lung and minimize systemic exposure. These have proved highly effective for most asthmatic subjects, but despite these developments, there are a number of subjects with asthma who fail to respond to even high doses of inhaled or even oral glucocorticoids. Advances in delineating the fundamental mechanisms of glucocorticoid pharmacology, especially the concepts of transactivation and transrepression and cofactor recruitment, have resulted in better understanding of the molecular mechanisms whereby glucocorticoids suppress inflammation. The existence of multiple mechanisms underlying glucocorticoid insensitivity raises the possibility that this might indeed reflect different diseases with a common phenotype, and studies examining the efficacy of potential new agents should be targeted toward subgroups of patients with severe corticosteroid-resistant asthma who clearly require effective new drugs and other approaches to improved asthma control.

Profiling of genes expressed in peripheral blood mononuclear cells predicts glucocorticoid sensitivity in asthma patients

Gene expression profiles were examined in freshly isolated peripheral blood mononuclear cells (PBMC) from two independent cohorts (training and test sets) of glucocorticoid (GC)-sensitive (n = 64) and GC-resistant (n = 42) asthma patients in search of genes that accurately predict responders and nonresponders to inhaled corticosteroids. A total of 11,812 genes were examined with high-density oligonucleotide microarrays in both resting PBMC (106 patients) and cells treated in vitro with IL-1beta and TNF-alpha combined (88 patients), with or without GC. A total of 5,011 genes were expressed at significant levels in the PBMC, and 1,334 of those were notably up-regulated or down-regulated by IL-1beta/TNF-alpha treatment. The expression changes of 923 genes were significantly reversed in GC responders in the presence of GC. The expression pattern of 15 of these 923 genes that most accurately separated GC responders (n = 26) from the nonresponders (n = 18) in the training set, based on the weighted voting algorithm, predicted the independent test set of equal size with 84% accuracy. The expression accuracy of these genes was confirmed by real-time-quantitative PCR, wherein 11 of the 15 genes predicted GC sensitivity at baseline with 84% accuracy, with one gene predicting at 81% in an independent cohort of 79 patients. We conclude that we have uncovered gene expression profiles in PBMC that predict clinical response to inhaled GC therapy with meaningful accuracy. Upon validation in an independent study, these results support the development of a diagnostic test to guide GC therapy in asthma patients.

Risk-benefit value of inhaled glucocorticoids: a pharmacokinetic/pharmacodynamic perspective

Inhaled glucocorticoids induce therapeutic and adverse systemic effects via the same types of receptors. Analysis of the pharmacokinetic/pharmacodynamic parameters of inhaled glucocorticoids generates a risk-benefit value (RBV). Targeted efficacy with minimal adverse effects helps to quantify an appropriate RBV. High lung deposition/targeting, high receptor binding, longer pulmonary retention, and high lipid conjugation are among the pharmacokinetic parameters to be considered for improved efficacy of the compound. Low or negligible oral bioavailability, small particle size and inactive drug at the oropharynx, high plasma protein binding, rapid metabolism, high clearance, and lower systemic concentrations are associated with low risks for adverse effects. Inhaled glucocorticoid potency is enhanced by solution inhalers, which result in higher pulmonary deposition and minimize local adverse effects. These properties, among others, determine the efficacy and safety of inhaled glucocorticoids. Currently available inhaled glucocorticoids do not provide the complete pharmacokinetic/pharmacodynamic parameters to optimize RBV, leaving room for improvement in the development of future agents.

Identification of a novel glucocorticoid receptor mutation in budesonide-resistant human bronchial epithelial cells

We developed a molecular genetic model to investigate glucocorticoid receptor (GR) signaling in human bronchial epithelial cells in response to the therapeutic steroid budesonide. Based on a genetic selection scheme using the human Chago K1 cell line and integrated copies of a glucocorticoid-responsive herpes simplex virus thymidine kinase gene and a green fluorescent protein gene, we isolated five Chago K1 variants that grew in media containing budesonide and ganciclovir. Three spontaneous budesonide-resistant subclones were found to express low levels of GR, whereas two mutants isolated from ethylmethane sulfonate-treated cultures contained normal levels of GR protein. Analysis of the GR coding sequence in the budesonide-resistant subclone Ch-BdE5 identified a novel Val to Met mutation at amino acid position 575 (GRV575M) which caused an 80% decrease in transcriptional regulatory functions with only a minimal effect on ligand binding activity. Homology modeling of the GR structure in this region of the hormone binding domain and molecular dynamic simulations suggested that the GRV575M mutation would have a decreased affinity for the LXXLL motif of p160 coactivators. To test this prediction, we performed transactivation and glutathione-S-transferase pull-down assays using the p160 coactivator glucocorticoid interacting protein 1 (GRIP1)/transcriptional intermediary factor 2 and found that GRV575M transcriptional activity was not enhanced by GRIP1 in transfected cells nor was it able to bind GRIP1 in vitro. Identification of the novel GRV575M variant in human bronchial epithelial cells using a molecular genetic selection scheme suggests that functional assays performed in relevant cell types could identify subtle defects in GR signaling that contribute to reduced steroid sensitivities in vivo.

Psychiatric diagnoses in inner city outpatients with moderate to severe asthma

OBJECTIVE

Psychiatric symptoms may be associated with increased asthma morbidity and mortality. However, no investigations have identified syndromal psychiatric diagnoses in asthma patients using current diagnostic criteria or examined treatment received for mental illness.

METHOD

We conducted structured clinical interviews on 32 patients with moderate to severe asthma to identify current and past psychiatric illness.

RESULTS

Twenty-five percent of subjects had current major depressive disorder, but only 25 percent of these received antidepressants. Anxiety disorders, including panic disorder (16 percent), and social (13 percent) and specific phobias (28 percent) were also common. All subjects with panic disorder were receiving appropriate therapy.

CONCLUSIONS

Asthma patients with moderate to severe asthma treated at community health facilities may have high rates of often untreated mood and anxiety disorders. Interventions aimed at identifying and treating psychiatric disorders in this population are needed.

Prevalence of cytomegalovirus infection in severe refractory ulcerative and Crohn's colitis

OBJECTIVES

Cytomegalovirus infection has been reported as a cause of refractory inflammatory bowel disease, but no data are available on its prevalence in severe colitis. The aim of this study was to evaluate the prevalence and outcome of cytomegalovirus infection in a consecutive series of patients with severe steroid refractory colitis admitted to our department from 1997 to 1999.

METHODS

Among 62 patients with severe colitis, 55 with ulcerative colitis and seven with Crohn's disease, 19 (30%) were resistant to intravenous steroids and bowel rest. In all of them, rectal biopsies were examined for cytomegalovirus (the flexible proctoscopy being performed without air insufflation and limited to the first 10 cm). Buffy coat preparation on leukocytes was also performed to detect systemic infection. If cytomegalovirus was not detected, cyclosporine was started.

RESULTS

In seven (five with ulcerative colitis and two with Crohn's disease) out of 19 (36%) patients with refractory disease, cytomegalovirus was diagnosed in the rectal specimens as well as by buffy coat preparation. Five patients went into remission after antiviral treatment (three with ganciclovir and two with foscarnet). One patient did not respond and was operated on. In one patient, cytomegalovirus was found in the surgical specimen.

CONCLUSIONS

Cytomegalovirus infection is a frequent cause of severe refractory colitis. Rectal biopsy should always be performed in severe steroid-resistant colitis.

Depression in Asthma: Prevalence and Clinical Implications

BACKGROUND: Asthma and depression are both common illnesses. Data suggest that the prevalence of asthma and asthma-related morbidity and mortality has increased in the past 2 decades. Asthma has long been considered an illness in which mood and emotions contribute to symptom exacerbation. Therefore, we reviewed the recent literature on depression in persons with asthma. DATA SOURCES: The MEDLINE (1966-1999) and PSYCHINFO (1967-1999) databases were used to find English-language articles on asthma and depression. Search terms included asthma, depression, dysthymia, and mood. DATA SYNTHESIS: This literature suggests depressive symptoms are more common in asthma patients than in the general population and perhaps even more common than in some other general medical conditions. Depression may be associated with asthma morbidity and mortality. Limited data suggest the older tricyclic antidepressants may improve both depression and asthma symptoms. However, no studies have examined the use of second-generation antidepressants in asthma patients. CONCLUSION: Depressive symptoms are common in asthma patients. However, the prevalence of depressive disorders in this population is not well determined. Future studies should focus on determining the prevalence of major depressive disorder in this population and the effect of antidepressants on mood and asthma symptoms.