Tag: Mechanism

Posted on

Discovered Mechanism Underlying “Farm Dust” Could Lead To Protection Against … – Lung Disease News


Lung Disease News

Discovered Mechanism Underlying “Farm Dust” Could Lead To Protection Against …
Lung Disease News
While known for many years that children growing up on farms were more protected from asthma, no conclusive scientific findings could support this hypothesis until now. To uncover the connection between the exposure to farm dust and protection against …
Allergy Study Could Lead To Asthma Prevention TreatmentPioneer News
Farm kids less likely to have asthma3News NZ
Farm dust protects against allergies?iAfrica.com

all 6 news articles »

View full post on asthma – Google News

Posted on

Nanotubes Connect CD4+ T Cells to Airway Smooth Muscle Cells: Novel Mechanism of T Cell Survival.

Related Articles

Nanotubes Connect CD4+ T Cells to Airway Smooth Muscle Cells: Novel Mechanism of T Cell Survival.

J Immunol. 2015 May 1;

Authors: Al Heialy S, Zeroual M, Farahnak S, McGovern T, Risse PA, Novali M, Lauzon AM, Roman HN, Martin JG

Abstract
Contact between airway smooth muscle (ASM) cells and activated CD4(+) T cells, a key interaction in diseases such as asthma, triggers ASM cell proliferation and enhances T cell survival. We hypothesized that direct contact between ASM and CD4(+) T cells facilitated the transfer of anti-apoptotic proteins via nanotubes, resulting in increased survival of activated CD4(+) T cells. CD4(+) T cells, isolated from PBMCs of healthy subjects, when activated and cocultured with ASM cells for 24 h, formed nanotubes that were visualized by immunofluorescence and atomic force microscopy. Cell-to-cell transfer of the fluorescent dye calcein-AM confirmed cytoplasmic communication via nanotubes. Immunoreactive B cell lymphoma 2 (Bcl-2) and induced myeloid leukemia cell differentiation protein (Mcl-1), two major anti-apoptotic proteins, were present within the nanotubes. Downregulation of Mcl-1 by small interfering RNA in ASM cells significantly increased T cell apoptosis, whereas downregulation of Bcl-2 had no effect. Transfer of GFP-tagged Mcl-1 from ASM cells to CD4(+) T cells via the nanotubes confirmed directionality of transfer. In conclusion, activated T cells communicate with ASM cells via nanotube formation. Direct transfer of Mcl-1 from ASM to CD(+) T cells via nanotubes is involved in T cell survival. This study provides a novel mechanism of survival of CD4(+) T cells that is dependent on interaction with a structural cell.

PMID: 25934863 [PubMed – as supplied by publisher]

View full post on pubmed: asthma

Posted on

The effect of unilateral adrenalectomy on transformation of adrenal medullary chromaffin cells in vivo: a potential mechanism of asthma pathogenesis.

The effect of unilateral adrenalectomy on transformation of adrenal medullary chromaffin cells in vivo: a potential mechanism of asthma pathogenesis.

PLoS One. 2012;7(9):e44586

Authors: Hu CP, Zou YQ, Feng JT, Li XZ

Abstract
BACKGROUND: Decreased epinephrine (EPI) is an important underlying factor of bronchoconstriction in asthma. Exogenous ?(2)-adrenergic receptor agonist is one of the preferred options to treat asthma. We previously showed that this phenomenon involved adrenal medullary chromaffin cell (AMCC) transformation to a neuron phenotype. However, the underlying molecular mechanism is not fully understood. To further explore this, an asthmatic model with unilateral adrenalectomy was established in this study.
METHODOLOGY/PRINCIPAL FINDINGS: Thirty-two rats were randomly into four groups (n?=?8 each) control rats (controls), unilateral adrenalectomy rats (surgery-control, s-control), asthmatic rats (asthma), unilateral adrenalectomy asthmatic rats (surgery-induced asthma, s-asthma). Asthmatic rats and s-asthmatic rats were sensitized and challenged with ovalbumin (OVA). The pathological changes in adrenal medulla tissues were observed under microscopy. EPI and its rate-limiting enzyme, phenylethanolamine N-methyl transferase (PNMT), were measured. Peripherin, a type III intermediate filament protein, was also detected in each group. The asthmatic rats presented with decreased chromaffin granules and swollen mitochondria in AMCCs, and the s-asthmatic rats presented more serious pathological changes than those in asthmatic rats and s-control rats. The expressions of EPI and PNMT in asthmatic rats were significantly decreased, as compared with levels in controls (P<0.05), and a further decline was observed in s-asthmatic rats (P<0.05). The expression of peripherin was higher in the asthmatic rats than in the controls, and the highest level was found in the s-asthmatic rats (P<0.05).
CONCLUSION/SIGNIFICANCE: Compared with asthmatic rats and s-control rats, the transformation tendency of AMCCs to neurons is more obvious in the s-asthmatic rats. Moreover, this phenotype alteration in the asthmatic rats is accompanied by reduced EPI and PNMT, and increased peripherin expression. This result provides further evidence to support the notion that phenotype alteration of AMCCs contributes to asthma pathogenesis.

PMID: 22957086 [PubMed – in process]

View full post on pubmed: asthma

Posted on

Anti-inflammatory and antinociceptive effects of salbutamol on acute and chronic models of inflammation in rats: involvement of an antioxidant mechanism.

Anti-inflammatory and antinociceptive effects of salbutamol on acute and chronic models of inflammation in rats: involvement of an antioxidant mechanism.

Mediators Inflamm. 2012;2012:438912

Authors: Uzkeser H, Cadirci E, Halici Z, Odabasoglu F, Polat B, Yuksel TN, Ozaltin S, Atalay F

Abstract
The possible role of ?-2 adrenergic receptors in modulation of inflammatory and nociceptive conditions suggests that the ?-2 adrenergic receptor agonist, salbutamol, may have beneficial anti-inflammatory and analgesic effects. Therefore, in this study, we induced inflammatory and nociceptive responses with carrageenan-induced paw edema or cotton-pellet-induced granuloma models, both of which result in oxidative stress. We hypothesized that salbutamol would prevent inflammatory and nociceptive responses by stimulating ?-2 adrenergic receptors and the prevention of generation of ROS during the acute inflammation process in rats. Both doses of salbutamol used in the study (1 and 2?mg/kg) effectively blocked the acute inflammation and inflammatory nociception induced by carrageenan. In the cotton-pellet-induced granuloma test, both doses of salbutamol also significantly decreased the weight of granuloma tissue on the cotton pellets when compared to the control. Anti-inflammatory and analgesic effects of salbutamol were found to be comparable with those of indomethacin. Salbutamol decreased myeloperoxidase (MPO) activity and lipid peroxidation (LPO) level and increased the activity of superoxide dismutase (SOD) and level of glutathione (GSH) during the acute phase of inflammation. In conclusion, salbutamol can decrease acute and chronic inflammation, possibly through the stimulation of ?-2 adrenergic receptors. This anti-inflammatory effect may be of significance in asthma treatment, where inflammation also takes part in the etiopathology. This study reveals that salbutamol has significant antioxidative effects, which at least partially explain its anti-inflammatory capabilities. These findings presented here may also shed light on the roles of ?-2 adrenergic receptors in inflammatory and hyperalgesic conditions.

PMID: 22665951 [PubMed – in process]

View full post on pubmed: asthma