Olive Leaf Extract (OLE) as a Novel Antioxidant That Ameliorates the Inflammatory Response in Cystic Fibrosis

Abstract

The deletion of phenylalanine at position 508 (F508del) produces a misfolded CFTR protein that is retained in the ER and degraded. The lack of normal CFTR channel activity is associated with chronic infection and inflammation which are the primary causes of declining lung function in Cystic Fibrosis (CF) patients. Moreover, LPS-dependent oxidative stress downregulates CFTR function in airway epithelial cells. Olive leaf extract (OLE) is used in traditional medicine for its effects, including anti-oxidant and anti-inflammatory ones. We found that OLE decreased the intracellular ROS levels in a dose–response manner in CFBE cells. Moreover, OLE attenuates the inflammatory response to LPS or IL-1β/TNFα stimulation, mimicking the infection and inflammatory status of CF patients, in CFBE and primary nasal epithelial (HNE) cells. Furthermore, we demonstrated that OLE restored the LPS-mediated decrease of TrikfaftaTM-dependent F508del-CFTR function in CFBE and HNE cultures. These findings provide strong evidence of OLE to prevent redox imbalance and inflammation that can cause chronic lung damage by enhancing the antioxidant activity and attenuating inflammation in CF airway epithelial cells. Additionally, OLE might be used in combination with CFTR modulators therapy to improve their efficacy in CF patients.

Nutritional Supplements for Skin Health—A Review of What Should Be Chosen and Why

“…Oleuropein has been shown to have a variety of medicinal effects. It was also discovered to have antiviral, antibacterial, anti-inflammatory, and antioxidant activities that may lower upper respiratory illness (URI) rates [124][125][126]. Olive leaf extract is currently sold either in cosmetics (oils, creams, or serums for topical use) or supplements for daily supplementation.…”

Olive Leaf Extracts from Three Italian Olive Cultivars Exposed to Drought Stress Differentially Protect Cells against Oxidative Stress

“…The antioxidant activity of olive leaf extracts (OLEs) is due to the presence of polyphenols [5], which makes them an ideal candidate in the medical, cosmetic, and pharmaceutical fields [6]. For example, OLEs' protective effects against oxidative stress were found in endothelial cells [7], in renal cells exposed to cadmium [8], and in bronchial epithelial cells affected by cystic fibrosis [9]. Oleuropein is the most abundant compound in OLE [10] and is thought to be primarily responsible for its pharmacological effects.…”