Bronchial epilepsy or broncho-pulmonary hyper-excitability as a model of asthma pathogenesis

A Novel Link between Early Life Allergen Exposure and Neuroimmune Development in Children

Purpose

As COVID-19 unprecedented situation significantly increased the time families spend indoors, the awareness of unhealthy living conditions negatively impacting immune system and early neurodevelopment of children is of crucial importance.

Methods

We retrospectively reviewed unrelated cases of the children with confirmed multiple indoor allergen sensitization due to prolonged exposure to unhealthy indoor environment with infestation and water damage, who, in addition to multiple health problems related to allergy and asthma, also developed neuroimmune complications and growth delay.

Results

Documented early in life atypical neurologic and behavioral changes were common in all cases. Clinical analysis did not establish other causative reason aside from prenatal and early life exposure to unhealthy living conditions. Alternaria Alternara and Penicillium/Aspergillus molds were found in all homes and sensitization was confirmed in all cases. Significant similarities in the symptoms recorded in all three families led us to a hypothesis that, likely, a significant level of the immune response to external immunogenic pathological stimulus such as mold spore protein, mycotoxin protein, dust mite protein, decay-related volatile particles (VOC) skewed a balance of the neuroimmune interactions, and further affected neuronal network establishment. As all children exhibited significant spectrum of the systemic inflammatory conditions early in life, coupled with inability to follow normal neurodevelopment, we hypothesize that an overwhelming activation of the aggressive immune mechanisms by the epigenetic factors led to glia activation, cytokine storm and break of tolerance.

Conclusions

We hypothesize that developing immune system exhibited aggressive responses due to environmental danger signals, subsequently TH-1 or TH-2 switch enables multiple clinical syndromes development with atypical presentation due to the described novel mechanism. An increased due to the COVID-19 lock-down may increase an amount of exposure of vulnerable people to indoor biological particles and volatile organic compounds present in unhealthy buildings. It is of crucial importance to identify and remediate indoor exposure factors that can decrease immune protection, especially against infectious pathogens such as novel coronavirus.

Association of epilepsy and asthma: a population-based retrospective cohort study

Background

Epidemiologic data supporting the epilepsy–asthma association are insufficient. Therefore, we examined this association in this study.

Methods

By using claims data from the National Health Insurance Research Database (Taiwan), we executed a retrospective cohort analysis. Analysis 1 entailed comparing 150,827 patients diagnosed as having incident asthma during 1996–2013 with disease-free controls who were selected randomly during the same period, frequency matched in terms of age and sex. Similarly, analysis 2 entailed comparing 25,274 patients newly diagnosed as having epilepsy with sex- and age-matched controls who were selected randomly. At the end of 2013, we evaluated in analysis 1 the epilepsy incidence and risk and evaluated in analysis 2 the asthma incidence and risk. We applied Kaplan–Meier analysis to derive plots of the proportion of asthma-free seizures.

Results

In analysis 1, the asthma group exhibited a higher epilepsy incidence than did the control group (3.05 versus 2.26 per 1,000 person-years; adjusted hazard ratio: 1.39, 95% CI [1.33–1.45]). We also noted a greater risk of subsequent epilepsy in women and girls. In analysis 2, we determined that the asthma incidence between the control and epilepsy groups did not differ significantly; however, some age subgroups including children and individuals in their 30s had an increased risk. A negative association was found in adolescents. The Kaplan–Meier analysis revealed epilepsy to be positively associated with subsequent onset of asthma within seven years of epilepsy diagnosis.

Discussion

Asthma may be associated with high epilepsy risk, and epilepsy may be associated with high asthma risk among children and individuals in their 30s. Nevertheless, people with epilepsy in other age subgroups should be aware of the possibility of developing asthma within seven years of epilepsy diagnosis.

The efficacy of specific neuromodulators on human refractory chronic cough: a systematic review and meta-analysis

BACKGROUND

There have been several published reports on the use of orally administered, specific centrally acting medicines for the treatment of idiopathic cough; however, there is no extant systematic review of randomized controlled trials (RCTs) that evaluated their efficacy and safety for the treatment of idiopathic cough in human beings.

METHODS

We conducted a series of definitive systematic reviews and meta-analyses of RCTs. Claims data from the MEDLINE, EMBASE, LILACS, CBM, CNKI, VIP, Wan Fang, and Cochrane Library databases were used. We also reviewed articles and reference lists of relevant articles pertaining to human subjects published prior to March 26, 2016. No language restrictions were imposed. Two authors independently reviewed the titles and abstracts of the retrieved studies, which were matched using Review Manager 5.3 software. Disagreements were resolved by consensus. The outcome data were the number of subjects whose symptoms declined, measured by cough or Leicester Cough Questionnaire (LCQ) score. Random effect meta-analyses were used to pool the findings. Publication bias was assessed using funnel plots.

RESULTS

Three RCTs, regarding the medicines baclofen, amitriptyline, and gabapentin, were conducted involving 92 persons in total. Our reviews confirmed that baclofen, amitriptyline, and gabapentin show promise in the treatment of cough for select cases of refractory chronic cough. After-treatment relief of cough symptoms was significant (risk ratio =2.41; 95% CI: 1.15-5.04, n=84). Each of the medicines was well tolerated with minimal side effects. Methodological biases in the design and execution of cluster randomized trials might contribute to any selection bias in this review.

CONCLUSIONS

Baclofen, amitriptyline, and gabapentin may be effective 'non-specific' antitussives in clinical settings, although none of them are used in medical assessments or routinely included in the anatomic diagnostic protocol.

Glufosinate aerogenic exposure induces glutamate and IL-1 receptor dependent lung inflammation

Glufosinate-ammonium (GLA), the active component of an herbicide, is known to cause neurotoxicity. GLA shares structural analogy with glutamate. It is a powerful inhibitor of glutamine synthetase (GS) and may bind to glutamate receptors. Since these potentials targets of GLA are present in lung and immune cells, we asked whether airway exposure to GLA may cause lung inflammation in mice. A single GLA exposure (1 mg/kg) induced seizures and inflammatory cell recruitment in the broncho-alveolar space, and increased myeloperoxidase (MPO), inducible NO synthase (iNOS), interstitial inflammation and disruption of alveolar septae within 6-24 h. Interleukin 1β (IL-1β) was increased and lung inflammation depended on IL-1 receptor 1 (IL-1R1). We demonstrate that glutamate receptor pathway is central, since the N-methyl-D-aspartate (NMDA) receptor inhibitor MK-801 prevented GLA-induced lung inflammation. Chronic exposure (0.2 mg/kg 3× per week for 4 weeks) caused moderate lung inflammation and enhanced airway hyperreactivity with significant increased airway resistance. In conclusion, GLA aerosol exposure causes glutamate signalling and IL-1R-dependent pulmonary inflammation with airway hyperreactivity in mice.

NMDA receptors mediate contractile responses in human airway smooth muscle cells

Human airway smooth muscle (HASM) exhibits enhanced contractility in asthma. Inflammation is associated with airway hypercontractility, but factors that underpin these features are not fully elucidated. Glutamate toxicity associated with increased plasma glutamate concentrations was observed in airway inflammation, suggesting that multisubunit glutamate receptors, N-methyl-d-aspartate receptors (NMDA-R) contribute to airway hyperreactivity. We tested the hypothesis that HASM expresses NMDA-R subunits that can form functional receptors to mediate contractile responses to specific extracellular ligands. In cultured HASM cells, we measured NMDA-R subunit mRNA and protein abundance by quantitative PCR, immunoblotting, flow cytometry, and epifluorescence immunocytochemistry. We measured mRNA for a number of NMDA-R subunits, including the obligatory NR1 subunit, which we confirmed to be present as a protein. In vitro and ex vivo functional NMDA-R activation in HASM cells was measured using intracellular calcium flux (fura-2 AM), collagen gel contraction assays, and murine thin-cut lung slices (TCLS). NMDA, a pharmacological glutamate analog, induced cytosolic calcium mobilization in cultured HASM cells. We detected three different temporal patterns of calcium response, suggesting the presence of heterogeneous myocyte subpopulations. NMDA-R activation also induced airway contraction in murine TCLS and soft collagen gels seeded with HASM cells. Responses in cells, lung slices, and collagen gels were mediated by NMDA-R, as they could be blocked by (2R)-amino-5-phosphonopentanoate, a specific NMDA-R inhibitor. In summary, we reveal the presence of NMDA-R in HASM that mediate contractile responses via glutamatergic mechanisms. These findings suggest that accumulation of glutamate-like ligands for NMDA-R associated with airway inflammation contributes directly to airway hyperreactivity.

Effects of neostigmine on bronchoconstriction with continuous electrical stimulation in rats

PURPOSE

When neostigmine is used to reverse muscle relaxants in patients with asthma without signs of airway inflammation, asthma attack is occasionally encountered. It is likely that abnormally increased electrical impulses traveling from the brain through cholinergic nerves to airway smooth muscles may be one of the pathogeneses of asthma attack. We applied continuous electrical field stimulation (c-EFS) or continuous electrical stimulation (c-ES) of low frequency to the vagal nerve of the rat in vitro and in vivo to determine the role of cholinergic nerve activation in inducing airway constriction.

METHODS

Fifty-seven male Wistar rats were used. In an in vitro study we examined whether tetrodotoxin (TTX), an Na(+)-channel blocker, 4-DAMP, a muscarinic M(3) receptor antagonist, or neostigmine could affect c-EFS-induced contraction of the tracheal ring. In an in vivo study, we examined whether c-ES of the vagal nerve could increase maximum airway pressure (P (max)) and whether neostigmine could potentiate c-ES-induced P (max).

RESULTS

TTX and 4-DAMP completely inhibited c-EFS-induced contraction whereas neostigmine potentiated c-EFS-induced contraction dose-dependently. P (max) was not increased by neostigmine. P (max) was not increased by 2-Hz c-ES, but was increased by the addition of neostigmine. P (max) was increased by 5-Hz c-ES, and further increased by the addition of neostigmine.

CONCLUSION

The contractile response of the tracheal ring to c-EFS is potentiated by neostigmine. P (max) is increased by c-ES of the vagal nerve, and is potentiated by neostigmine. These data suggest that increased activity of the cholinergic nerve could be involved in asthma attack.

Common causes of uncommon seizures

Afebrile seizures associated with rotavirus gastroenteritis, respiratory syncytial virus bronchiolitis, influenza infection, asthma, blood transfusions, and intake of a number of drugs (including theophylline, cephalosporins, metronidazole, and acyclovir) with therapeutic drug levels are uncommonly encountered in clinical practice. Reviewed here are the incidence, etiology, clinical presentation, types, diagnosis, associated electroencephalographic changes, and cranial magnetic resonance imaging findings in the literature, as well as management and prognosis of these seizures.

Neuro-bioenergetic concepts in cancer prevention and treatment

Cancer remains one of the most difficult and elusive disorders to prevent and treat, despite great efforts in research and treatment over the last 30 years. Researchers have tried to understand the pathogenesis of cancer by discovering the single cellular mechanism or pathway derived from a genetic mutation. There are limited efforts made toward discovering a unified concept of cancer. We propose a neuro-bioenergetic concept of cancer pathogenesis based on the central mechanism of cellular hyperexcitability via inducible overexpression of voltage-gated ion channels, ligand-gated channels and neurotransmitters. Exploration of this concept could lead to a better understanding of the cause of cancer as well as developing more effective and specific strategies toward cancer prevention and treatment.