Oleuropein down-regulated IL-1β-induced inflammation and oxidative stress in human synovial fibroblast cell line SW982

Secoiridoids of olive and derivatives as potential coadjuvant drugs in cancer: A critical analysis of experimental studies

Phenolic secoiridoids from olive, including oleocanthal, oleuropein and related derivatives, are bioactive natural products with documented anticancer activities, that have mainly been attributed to their antioxidant, anti-inflammatory and antiproliferative effects. This review summarizes the results of the preclinical studies on the natural secoiridoids of olive used as single agents or in combination with other chemotherapeutics against cancer cells. The molecular targets of their action are described. A critical analysis of the importance of the experimental studies in view of the possible use in humans is also discussed.

Effects of Olive Leaf Extract on Metabolic Response, Liver and Kidney Functions and Inflammatory Biomarkers in Hypertensive Patients

BACKGROUND AND OBJECTIVE

Hypertension is a long-term medical condition in which the blood pressure is gradually elevated. In this project, the effects of olive leaf extract (OLE) were evaluated on metabolic response, liver and kidney functions and also biomarkers of inflammation in hypertensive patients.

MATERIALS AND METHODS

In this randomized double-blind placebo controlled clinical trial, 60 hypertensive patients, aged 30-60 years old had participated. Patients were randomly assigned into two groups to receive either OLE or placebo tablets for 12 weeks. At the beginning and end of the intervention, metabolic parameters and biomarkers of liver, kidney and inflammation were measured in sera of the participants using available laboratory methods.

RESULTS

Compared with the placebo, changes in parameters associated with glucose metabolism were not statistically significant (p>0.05). The OLE tablets did not have significant effect on liver enzymes, total protein, albumin, urea and creatinine (p>0.05), but significantly decreased interleukin-6, interleukin-8 and tumor necrosis factor alpha as inflammatory biomarkers (p<0.05) in OLE group compared to the placebo group.

CONCLUSION

The results concluded that inflammation as a major cause of hypertension was significantly decreased in patients using OLE tablets.

Polyphenolic extract from extra virgin olive oil inhibits the inflammatory response in IL-1β-activated synovial fibroblasts

The polyphenolic extract (PE) from extra virgin olive oil (EVOO) has been shown to possess important anti-inflammatory and joint protective properties in murine models of rheumatoid arthritis (RA). This study was designed to evaluate the effects of PE on IL-1β-activated human synovial fibroblasts SW982 cell line. PE from EVOO treatment inhibited IL-1β-induced matrix metalloproteases (P&lt;0·001), TNF-α and IL-6 production (P&lt;0·001). Similarly, IL-1β-induced cyclo-oxygenase-2 and microsomal PGE synthase-1 up-regulations were down-regulated by PE (P&lt;0·001). Moreover, IL-1β-induced mitogen-activated protein kinase (MAPK) phosphorylation and NF-κB activation were ameliorated by PE (P&lt;0·001). These results suggest that PE from EVOO reduces the production of proinflammatory mediators in human synovial fibroblasts; particularly, these protective effects could be related to the inhibition of MAPK and NF-κB signalling pathways. Taken together, PE from EVOO probably could provide an attractive complement in management of diseases associated with over-activation of synovial fibroblasts, such as RA.

Olive Fruit Blends Modulate Lipid-Sensing Nuclear Receptor PPARγ, Cell Survival, and Oxidative Stress Response in Human Osteoblast Cells

OBJECTIVE

The aim of the present study was to investigate how different extravirgin olive oils (EVOOs), obtained by blending Olea europea cultivars, could influence the cell growth, the response to inflammatory stimuli, and oxidative stress in a culture of the osteosarcoma cell line Saos-2.

METHODS

Three different extravirgin olive oils were physicochemically characterized, determining the free acidity, the oxidation status, the polyphenols content, and the antioxidative activity. Moreover, the effects on Saos-2 cell culture were determined, studying the mRNA expression level by real-time polymerase chain reaction (PCR) assays and the antioxidative activity using fluorescent probes.

RESULTS

The cultivars used in the south of Italy, yield extravirgin oils with different amount of fatty acids and polyphenols, which counteract induction of proinflammatory cytokines and regulate free radical production in hydrogen peroxide-stimulated cells. In vitro analysis using the human osteoblast cell line Saos-2 showed that the addition of oils to cell culture simulated a hypoxic stress followed by a reoxygenation period, during which the antioxidant activity of extravirgin olive oils protected cells from oxidative damages. On the other hand, the mRNA expression levels of factors involved in inflammatory processes, cell growth recovery, and antioxidant response, as heme oxygenase-1, were differently stimulated by EVOOs. Moreover, peroxisome proliferator activated receptor γ (PPARγ) was differently modulated by EVOOs.

CONCLUSION

These findings show that the blending of different extravirgin olive oil can impact an osteoblast cell line, in particular regarding cell growth recovery and oxidative stress.

Oleuropein inhibits the IL-1β-induced expression of inflammatory mediators by suppressing the activation of NF-κB and MAPKs in human osteoarthritis chondrocytes

Osteoarthritis (OA) is the most common form of joint disease and is widespread in the elderly population and is characterized by erosion of articular cartilage, subchondral bone sclerosis and synovitis. Oleuropein (OL), a secoiridoid, is considered as the most prevalent phenolic component in olive leaves and seeds, pulp and peel of unripe olives and has been shown to have potent anti-inflammatory effects. However, its effects on OA have not been clearly elucidated. This study aimed to assess the effect of OL on human OA chondrocytes. Human OA chondrocytes were pretreated with OL (10, 50 and 100 μM) for 2 h and subsequently stimulated with IL-1β for 24 h. The production of NO, PGE2, MMP-1, MMP-13, and ADAMTS-5 was evaluated by the Griess reaction and ELISA assays. The messenger RNA (mRNA) expression of COX-2, iNOS, MMP-1, MMP13, ADAMTS-5, aggrecan, and collagen-II was measured by using real-time PCR. The protein expressions of COX-2, iNOS, p65, IκB-α, JNK, p-JNK, ERK, p-ERK, p38, and p-p38 were tested by using western blot. We found that OL significantly inhibited the IL-1β-induced production of NO and PGE2; expression of COX-2, iNOS, MMP-1, MMP-13, and ADAMTS-5; and degradation of aggrecan and collagen-II. Furthermore, OL dramatically suppressed IL-1β-stimulated NF-κB and MAPK activation. Immunofluorescence staining demonstrated that OL could suppress IL-1β-induced phosphorylation of p65 nuclear translocation. These results indicate that the therapeutic effect of OL on OA is accomplished through the inhibition of both NF-κB and MAPK signaling pathways. Altogether, our findings provide the evidence to develop OL as a potential therapeutic agent for patients with OA.