20 research outputs found
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Modulation of intestinal epithelium homeostasis by extra virgin olive oil phenolic compounds
Dietary habits have been strongly linked to the maintenance of intestinal epithelium homeostasis, whose alteration may contribute to the pathogenesis of inflammatory diseases and cancer. Polyphenols are among those dietary components suggested to be beneficial for gut health. Within a balanced Mediterranean type diet, a good portion of ingested polyphenols comes from olives and extra virgin olive oil (EVOO). Most of them reach the intestine, where they may be directly absorbed or metabolized under absorption. Others undergo an extensive gastrointestinal biotransformation, producing various metabolites that retain the potential beneficial effect of the parent compounds, or exert a more efficient biological action themselves. Ingested EVOO polyphenols (EVOOP) and their metabolites will be particularly concentrated in the intestinal lumen, where they might exert a significant local action. In this review we summarize the few studies that investigated the effect of EVOOP at the intestinal level, focusing on the possible mechanism of action in relation to their interaction with the microbiota, and their ability to potentially modulate the oxidative status of the intestinal epithelial layer, inflammation and immune response
Harmful effect of oxysterols in the gut and at systemic level: modulatory activity of olive oil phenolics
A healthy and proper diet is essential to prevent the onset of various diseases, as with the diet we can also introduce harmful substances.
Among others, the oxysterols are particularly relevant; they can be absorbed from the diet and are the oxidized products of cholesterol present in cholesterol-containing foodstuffs after cooking, processing and storage, such as meat, fish, dairy products and eggs. They can be also generated endogenously from either the spontaneous or enzymatic oxidation of cholesterol.
Oxysterols have been shown to exert several in vitro and in vivo biochemical activities, physiological but mostly pathological. In particular, they may induce cytotoxicity, cell death (necrosis and apoptosis), pro-oxidant and pro-inflammatory effects in different cells and tissues and have been linked with the onset and development of major chronic diseases.
Only in the last few years, oxysterols have been shown to interfere with the homeostasis of the human digestive tract, demonstrating their involvement in the pathogenesis of human inflammatory bowel disease and colon rectal cancer.
Experimental studies suggest that the ingestion of compounds with antioxidant action, such as phenolics, is able to counteract the oxidative stress and inflammatory response in the intestine and inhibit the onset of the main related diseases.
Extra virgin olive oil polyphenols in particular, recognized for their strong antioxidant property and related anti-inflammatory action, may display this effect in the intestinal lumen where they concentrate before absorption, preventing intestinal diseases.
The first aim of this study was to evaluate the ability of different extra virgin olive oil phenolic extracts to counteract the pro-oxidant, pro-apoptotic and pro-
inflammatory action of oxysterols in the human colon adenocarcinoma cell line (Caco-2) and the molecular mechanism involved.
Oxysterols treatment, depending on time of exposure and concentrations used, significantly altered the cellular redox status (ROS production increase, GSH decrease, GPX activity enhancement), induced an oxidative damage to the membrane lipid fraction (MDA production increase) and cell death (Caspase 3 increase); cytokines production (IL-6, IL-8) was indicative of a pro-inflammatory effect. Phenolic extracts were able to significantly counteract the oxysterols harmful effects, at least in part by modulating intracellular signaling pathways (Akt/PKB, MAPK) involved in the cellular response to oxidative stress, apoptosis and inflammation.
Several studies in animals and humans have shown that dietary oxysterols, after digestion can be absorbed from the gut and transported into the circulation within chylomicrons and other lipoproteins. Furthermore, the presence of oxysterols in plasma can derive from the oxidation of endogenous cholesterol through enzymatic or spontaneous reactions.
Oxysterols have been found at increased levels in the plasma of hypercholesterolemic subjects and have been linked with the atherosclerotic process.
In this context the second part of this study was specifically focused on the protective effect of pure olive oil phenolics, which can be found in the blood stream after absorption (hydroxytyrosol, tyrosol, and homovanillc alcohol), against the pro-oxidant and pro-inflammatory activity of oxysterols in blood cells (PBMCs).
It was demonstrated that all phenolic compounds tested, HT, TYR and HVA were able to inhibit oxysterol-induced pro-inflammatory cytokines production.
According to the hypotesis that pro-inflammatory cytokine release may be induced by changes in intracellular redox status, it was observed that, in human
PBMCs treated with the oxysterols mixture, simple phenols were also able to inhibit ROS production as well as to suppress both redox-based MAPK phosphorylation (JNK, p38).
These data suggest that olive oil phenolic extracts may significantly contribute to preserve the integrity of intestinal mucosa against oxidative damage and inflammation related disorders and simple phenols found in the blood after metabolism and absorption counteract the oxysterols-induced inflammatory effect at systemic level
Harmful effect of oxysterols in the gut and at systemic level: modulatory activity of olive oil phenolics
A healthy and proper diet is essential to prevent the onset of various diseases, as with the diet we can also introduce harmful substances.
Among others, the oxysterols are particularly relevant; they can be absorbed from the diet and are the oxidized products of cholesterol present in cholesterol-containing foodstuffs after cooking, processing and storage, such as meat, fish, dairy products and eggs. They can be also generated endogenously from either the spontaneous or enzymatic oxidation of cholesterol.
Oxysterols have been shown to exert several in vitro and in vivo biochemical activities, physiological but mostly pathological. In particular, they may induce cytotoxicity, cell death (necrosis and apoptosis), pro-oxidant and pro-inflammatory effects in different cells and tissues and have been linked with the onset and development of major chronic diseases.
Only in the last few years, oxysterols have been shown to interfere with the homeostasis of the human digestive tract, demonstrating their involvement in the pathogenesis of human inflammatory bowel disease and colon rectal cancer.
Experimental studies suggest that the ingestion of compounds with antioxidant action, such as phenolics, is able to counteract the oxidative stress and inflammatory response in the intestine and inhibit the onset of the main related diseases.
Extra virgin olive oil polyphenols in particular, recognized for their strong antioxidant property and related anti-inflammatory action, may display this effect in the intestinal lumen where they concentrate before absorption, preventing intestinal diseases.
The first aim of this study was to evaluate the ability of different extra virgin olive oil phenolic extracts to counteract the pro-oxidant, pro-apoptotic and pro-
inflammatory action of oxysterols in the human colon adenocarcinoma cell line (Caco-2) and the molecular mechanism involved.
Oxysterols treatment, depending on time of exposure and concentrations used, significantly altered the cellular redox status (ROS production increase, GSH decrease, GPX activity enhancement), induced an oxidative damage to the membrane lipid fraction (MDA production increase) and cell death (Caspase 3 increase); cytokines production (IL-6, IL-8) was indicative of a pro-inflammatory effect. Phenolic extracts were able to significantly counteract the oxysterols harmful effects, at least in part by modulating intracellular signaling pathways (Akt/PKB, MAPK) involved in the cellular response to oxidative stress, apoptosis and inflammation.
Several studies in animals and humans have shown that dietary oxysterols, after digestion can be absorbed from the gut and transported into the circulation within chylomicrons and other lipoproteins. Furthermore, the presence of oxysterols in plasma can derive from the oxidation of endogenous cholesterol through enzymatic or spontaneous reactions.
Oxysterols have been found at increased levels in the plasma of hypercholesterolemic subjects and have been linked with the atherosclerotic process.
In this context the second part of this study was specifically focused on the protective effect of pure olive oil phenolics, which can be found in the blood stream after absorption (hydroxytyrosol, tyrosol, and homovanillc alcohol), against the pro-oxidant and pro-inflammatory activity of oxysterols in blood cells (PBMCs).
It was demonstrated that all phenolic compounds tested, HT, TYR and HVA were able to inhibit oxysterol-induced pro-inflammatory cytokines production.
According to the hypotesis that pro-inflammatory cytokine release may be induced by changes in intracellular redox status, it was observed that, in human
PBMCs treated with the oxysterols mixture, simple phenols were also able to inhibit ROS production as well as to suppress both redox-based MAPK phosphorylation (JNK, p38).
These data suggest that olive oil phenolic extracts may significantly contribute to preserve the integrity of intestinal mucosa against oxidative damage and inflammation related disorders and simple phenols found in the blood after metabolism and absorption counteract the oxysterols-induced inflammatory effect at systemic level
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Olive oil phenolics prevent oxysterol-induced proinflammatory cytokine secretion and reactive oxygen species production in human peripheral blood mononuclear cells, through modulation of p38 and JNK pathways
The aim of the present study was to investigate the ability of extra virgin olive oil (EVOO) polyphenols to counteract the proinflammatory effects induced by dietary and endogenous oxysterols in ex vivo immune cells. Peripheral blood mononuclear cells (PBMCs), separated from the whole blood of healthy donors, were utilized and were stimulated with an oxysterols mixture, in the presence of physiologically relevant concentrations of the EVOO polyphenols, hydroxytyrosol, tyrosol, and homovanillic alcohol. Oxysterols significantly increased the production of proinflammatory cytokines, interleukin-1β, regulated on activation, normal T-cell expressed and secreted and macrophage migration inhibitory factor in ex vivo cultured PBMCs. Increased levels of reactive oxygen species (ROS) were also detected along with increased phosphorylation of the p38 and JNK. All phenolic compounds significantly reduced cytokine secretion induced by the oxysterols and inhibited ROS production and mitogen activated protein kinase phosphorylation. These results suggest that extra virgin olive oil polyphenols modulate the immune response induced by dietary and endogenous cholesterol oxidation products in human immune cells and may hold benefit in controlling chronic immune and/or inflammatory processes
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Synthetic, non-intoxicating 8,9-dihydrocannabidiol for the mitigation of seizures
There can be a fine line between therapeutic intervention and substance abuse, and this point is clearly exemplified in herbal cannabis and its products. Therapies involving cannabis have been the treatment of last resort for some cases of refractory epilepsy, and this has been among the strongest medical justifications for legalization of marijuana. In order to circumvent the narcotic effects of 9-tetrahydrocannabinol (THC), many studies have concentrated on its less intoxicating isomer cannabidiol (CBD). However, CBD, like all natural cannabinoids, is a controlled substance in most countries, and its conversion into THC can be easily performed using common chemicals. We describe here the anticonvulsant properties of 8,9-dihydrocannibidiol (H2CBD), a fully synthetic analogue of CBD that is prepared from inexpensive, non-cannabis derived precursors. H2CBD was found to have effectiveness comparable to CBD both for decreasing the number and reducing the severity of pentylenetetrazole-induced seizures in rats. Finally, H2CBD cannot be converted by any reasonable synthetic route into THC, and thus has the potential to act as a safe, noncontroversial drug for seizure mitigation
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Raw and sous-vide-cooked red cardoon stalks (Cynara cardunculus L. var. altilis DC): (poly)phenol bioaccessibility, anti-inflammatory activity in the gastrointestinal tract, and prebiotic activity
The in vitro anti-inflammatory and prebiotic activity and the content and profile of bioaccessible (poly)phenols and catabolites of raw and sous-vide-cooked red cardoon (Cynara cardunculus L. var. altilis DC) were investigated during gastrointestinal (GI) digestion. Raw cardoon after in vitro GI digestion had 0.7% bioaccessible (poly)phenols, which protected against lipopolysaccharide-induced inflammation by counteracting IL-8, IL-6, TNF-α, and IL-10 secretions in differentiated Caco-2 cells. Contrarily, GI-digested sous vide cardoon showed higher (poly)phenol bioaccessibility (59.8%) and exerted proinflammatory effects in Caco-2 cells. (Poly)phenols were highly metabolized during the first 8 h of in vitro fermentation, and nine catabolites were produced during 48 h of fermentation. Colonic-fermented raw and sous-vide-cooked cardoon did not show anti-inflammatory activity in HT-29 cells but presented potential prebiotic activity, comparable to the commercial prebiotic FOS, by stimulating health-promoting bacteria such as Bifidobacterium spp. and Lactobacillus/Enterococcus spp. and by increasing the production of total SCFAs, especially acetate
Olive oil phenolic compounds modulate immune function in oxysterols-stimulated peripheral blood mononuclear cells
Recommended from our members
Synthetic, non-intoxicating 8,9-dihydrocannabidiol for the mitigation of seizures.
There can be a fine line between therapeutic intervention and substance abuse, and this point is clearly exemplified in herbal cannabis and its products. Therapies involving cannabis have been the treatment of last resort for some cases of refractory epilepsy, and this has been among the strongest medical justifications for legalization of marijuana. In order to circumvent the narcotic effects of Δ9-tetrahydrocannabinol (THC), many studies have concentrated on its less intoxicating isomer cannabidiol (CBD). However, CBD, like all natural cannabinoids, is a controlled substance in most countries, and its conversion into THC can be easily performed using common chemicals. We describe here the anticonvulsant properties of 8,9-dihydrocannibidiol (H2CBD), a fully synthetic analogue of CBD that is prepared from inexpensive, non-cannabis derived precursors. H2CBD was found to have effectiveness comparable to CBD both for decreasing the number and reducing the severity of pentylenetetrazole-induced seizures in rats. Finally, H2CBD cannot be converted by any reasonable synthetic route into THC, and thus has the potential to act as a safe, noncontroversial drug for seizure mitigation