Pinus sylvestris L. and Syzygium aromaticum (L.) Merr. & L. M. Perry Essential Oils Inhibit Endotoxin-Induced Airway Hyperreactivity despite Aggravated Inflammatory Mechanisms in Mice

Abstract

Scots pine (SO) and clove (CO) essential oils (EOs) are commonly used by inhalation, and their main components are shown to reduce inflammatory mediator production. The aim of our research was to investigate the chemical composition of commercially available SO and CO by gas chromatography–mass spectrometry and study their effects on airway functions and inflammation in an acute pneumonitis mouse model. Inflammation was evoked by intratracheal endotoxin and EOs were inhaled three times during the 24 h experimental period. Respiratory function was analyzed by unrestrained whole-body plethysmography, lung inflammation by semiquantitative histopathological scoring, myeloperoxidase (MPO) activity and cytokine measurements. α-Pinene (39.4%) was the main component in SO, and eugenol (88.6%) in CO. Both SO and CO significantly reduced airway hyperresponsiveness, and prevented peak expiratory flow, tidal volume increases and perivascular edema formation. Meanwhile, inflammatory cell infiltration was not remarkably affected. In contrast, MPO activity and several inflammatory cytokines (IL-1β, KC, MCP-1, MIP-2, TNF-α) were aggravated by both EOs. This is the first evidence that SO and CO inhalation improve airway function, but enhance certain inflammatory parameters. These results suggest that these EOs should be used with caution in cases of inflammation-associated respiratory diseases.

In vivo determination of the anti-inflammatory and antioxidant effects of the aqueous extract of Syzygium aromaticum (clove) in an asthmatic rat model

“…All the previously obtained results corroborate those of the present histopathological study of the lungs. Indeed, in asthmatic rats (OVA batch), infiltration of granulocytes, neutrophils, and macrophages was associated with the occurrence of perivascular and peribronchial edema, as shown in Figure 4 (black, white, and red arrows) [58]. Most of these inflammatory cells are composed of lymphocytes and eosinophils and are mainly located around the small bronchi, bronchioles, and blood vessels.…”

“…In addition to the infiltration of these cells, edema is also present [13]. However, treatment with the aqueous extracts of the S. aromaticum plant helped in reducing alveolar edema by decreasing pulmonary inflammation and reducing the concentrations of inflammatory cells and their infiltration into the lumen of the bronchioles [58]. In this regard, it is necessary to measure the effects of other medicinal plants [59][60][61].…”

Drug therapy possibilities for various forms of chronic rhinitis accompanied by dry nose syndrome

“…Широко представлены положительные качества фитопрепаратов, Bronchopulmonology, otorhinolaryngology приготовленных из разных частей сосны обыкновенной (хвои, почек, смолы) [44]. Исследование in vivo на животных продемонстрировало доказательства того, что ингаляции эфирным маслом сосны обыкновенной (Pinus sylvestris L.) снижают воспалительную гиперреактивность дыхательных путей и не вызывают гистопатологических изменений [45].…”

An Update on the Therapeutic Anticancer Potential of Ocimum sanctum L.: “Elixir of Life”

“…In animal models of pulmonary disease, eugenol was shown to have anti-inflammatory effects, as measured by a reduction in both TNF- and neutrophil infiltration. When the substance was administered at a dose of 160 mg/kg body weight in lung polymorphonuclear (PMN) infiltration [ 127 ], there was a decrease in the alveolar collapse that was observed. In addition, eugenol prevented chemically induced dysfunction in macrophage cells and restored balance to pro/mouse peritoneal macrophages, which are cells that produce anti-inflammatory mediators [ 127 , 128 , 129 ].…”