Endomorphin-2- and Neurotensin- Based Chimeric Peptide Attenuates Airway Inflammation in Mouse Model of Nonallergic Asthma

Abstract

We examined anti-inflammatory potency of hybrid peptide-PK20, composed of neurotensin (NT) and endomorphin-2 (EM-2) pharmacophores in a murine model of non-atopic asthma induced by skin sensitization with 2,4-dinitrofluorobenzene and intratracheal challenge of cognate hapten. Mice received intraperitoneally PK20, equimolar mixture of its structural elements (MIX), dexamethasone (DEX), or NaCl. Twenty-four hours following hapten challenge, the measurements of airway responsiveness to methacholine were taken. Bronchoalveolar lavage (BALF) and lungs were collected for further analyses. Treatment with PK20, similarly to dexamethasone, reduced infiltration of inflammatory cells, concentration of mouse mast cell protease, IL-1β, IL-12p40, IL-17A, CXCL1, RANTES in lungs and IL-1α, IL-2, IL-13, and TNF-α in BALF. Simple mixture of NT and EM-2 moieties was less potent. PK20, DEX, and MIX significantly decreased malondialdehyde level and secretory phospholipase 2 activity in lungs. Intensity of NF-κB immunoreactivity was diminished only after PK20 and DEX treatments. Neither PK20 nor mixture of its pharmacophores were as effective as DEX in alleviating airway hyperresponsiveness. PK20 effectively inhibited hapten-induced inflammation and mediator and signaling pathways in a manner seen with dexamethasone. Improved anti-inflammatory potency of the hybrid over the mixture of its moieties shows its preponderance and might pose a promising tool in modulating inflammation in asthma.

Inhalations with Brine Solution from the ‘Wieliczka’ Salt Mine Diminish Airway Hyperreactivity and Inflammation in a Murine Model of Non-Atopic Asthma

“…Apart from airway hyperreactivity, another feature of asthma is the airway inflammation described by the influx of inflammatory cells into the airways and the levels of inflammatory cytokines in both the lung tissue and BALF. The total number of inflammatory cells in sensitized, non-inhaled animals in our study was about three to ten times higher than in previous reports [42,43], which is probably in relation to the repeated hapten challenge. Moreover, we obtained a comparably elevated level of neutrophils, together with a lack of eosinophils, as it was observed previously [42,43].…”

“…The total number of inflammatory cells in sensitized, non-inhaled animals in our study was about three to ten times higher than in previous reports [42,43], which is probably in relation to the repeated hapten challenge. Moreover, we obtained a comparably elevated level of neutrophils, together with a lack of eosinophils, as it was observed previously [42,43]. Neutrophilia and the absence of eosinophils are key features of non-atopic asthma [44], both in humans and in animal models [45], which may determine the cytokine spectrum in blood, BALF, and lung tissue [1].…”

Contribution of opioid and neurotensin receptors in the anti‐inflammatory activity of PK20 hybrid compound in murine airways

“…Our latest report confirmed that the chimera alleviated inflammatory symptoms in the murine model of nonallergic asthma induced by sensitization with 1‐fluoro‐2,4‐dinitrobenzene (DNFB); a low molecular weight compound 16 . In fact, it has been proven that PK20 reduced influx of inflammatory cells into bronchoalveolar lavage fluid (BALF) and lungs, limited expression of nuclear transcription factor NF‐κB and concentration of pro‐inflammatory cytokines, malondialdehyde (MDA), secretory phospholipase A 2 (sPLA 2 ) and mouse mast cell protease (MCPT 1) in lung tissue, as well as the level of albumin in BALF.…”

“…In fact, it has been proven that PK20 reduced influx of inflammatory cells into bronchoalveolar lavage fluid (BALF) and lungs, limited expression of nuclear transcription factor NF‐κB and concentration of pro‐inflammatory cytokines, malondialdehyde (MDA), secretory phospholipase A 2 (sPLA 2 ) and mouse mast cell protease (MCPT 1) in lung tissue, as well as the level of albumin in BALF. In the same experimental conditions, the beneficial inhibitory impact of PK20 was revealed on airway hyperreactivity (AHR) in response to methacholine provocation 16 …”

Neurotransmitter and neuropeptide regulation of mast cell function: a systematic review

“…However, NT reduced mouse MC protease and malondialdehyde in lung homogenates in a murine hapten-induced asthma model, and the NTR1 antagonist did not reverse the NT-mediated reduced mouse MC activation [ 134 ]. Moreover, NT-based chimeric peptide and endomorphin-2 also reduced the concentration of mouse MC protease in a similar model [ 135 ].…”