Antisteatotic and antioxidant activities of Thymbra spicata L. extracts in hepatic and endothelial cells as in vitro models of non-alcoholic fatty liver disease

Natural Products from the Mediterranean Area as Wound Healing Agents-In Vitro Studies: A Systematic Review

Wound healing is a process that happens when lost tissue replenishes. For this process, both protective elements and wound healing accelerating factors are required. In recent years, the search for natural products that promote faster healing and prevent adverse effects has gained momentum. This is a systematic review, adhering to PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) criteria, of the wound healing effects of natural products, with a focus on natural products from the Mediterranean region. This study sourced the PubMed and Scopus databases for eligible articles and publications over the last six years. Due to the information volume, only the in vitro studies were included in this review. The criteria set concluded in the 28 studies included. These studies showed that many natural products found in the Mediterranean have been studied for the treatment of wounds. The wound healing effect seems to be related to dose, type of wounded tissue, and application time. Moreover, half of the studies were additionally tested and shown antioxidant activity through DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and FRAP (Ferric Reducing Antioxidant Power) assays.

Thymbra spicata extract and arbuscular mycorrhizae improved the morphophysiological traits, biochemical properties, and essential oil content and composition of Rosemary (Rosmarinus officinalis L.) under salinity stress

BACKGROUND

Enhancing the content of essential oils and valuable secondary metabolites is a primary goal for medicinal plant breeders. In this study, the effects of Thymbra spicata extract at concentrations of 0% (C), 10% (TS1), and 20% (TS2), along with mycorrhizal fungus (MF) biofertilizer at a rate of 50 g/2.5 kg of soil, were evaluated on the growth, photosynthetic pigments, relative water content (RWC), proline, protein, malondialdehyde (MDA), catalase (CAT), phenylalanine ammonia-lyase (PAL), and essential oil content and composition of Rosmarinus officinalis L. under varying salinity stress levels of 0 mM (S0), 100 mM (S1), and 200 mM (S2) NaCl. The experiment was conducted as a factorial study within a completely randomized design, with three replications.

RESULTS

As salinity stress increased, the yield and growth characteristics of the plants declined. However, the applied treatments effectively mitigated the negative effects of salinity. The highest chlorophyll a, b, and total chlorophyll contents were observed in the TS2 + MF treatment under nonsaline conditions. Under S2 salinity stress, carotenoid and anthocyanin contents increased by 38.29% and 11.11%, respectively, with the use of TS2 + MF. Under S1 stress conditions, the proline and soluble sugar content increased by 268% and 44%, respectively, in the MF treatment. Essential oil content was enhanced by 80.43% with the TS2 + MF treatment under S1 stress. Essential oil analysis showed significant increases in camphene (9.71%), β-pinene (43.75%), α-phellandrene (13.3%), geranyl acetate (156%), cineole (21.39%), and β-linalool (5.12%) in the TS2 + MF treatment compared to the control under S1 stress conditions.

CONCLUSIONS

Among all the treatments, the combined application of TS2 and MF proved to be the most effective in enhancing the morphophysiological and biochemical characteristics of rosemary plants. This treatment not only boosted the production of essential oils and secondary metabolites but also mitigated the detrimental effects of salinity stress. Therefore, it is recommended as a beneficial agricultural practice for improving the productivity and quality of rosemary plants under salinity stress.

Herbal Medicine in Three Different Mediterranean Living Areas During the COVID-19 Pandemic: The Role of Polyphenolic-Rich Thyme-like Plants

Despite herbal medicine being popular across the Mediterranean basin, there is no evidence in favor of COVID-19 infection. This study investigates the utilization and effects of medicinal plants in Italy, Lebanon, and Tunisia during COVID-19 and its effects on post-COVID-19 pandemics. We used a tailored, web-based "Google Form" questionnaire with the random sampling method. We gathered 812 complete responses (Italy: 116, Lebanon: 557, and Tunisia: 139), revealing diverse demographics and symptom experiences. Fatigue prevailed across all groups (89.0-94.2%), while psychological impacts ranged from 20.1% to 30.9%, with higher rates in Lebanon. Post-COVID-19 symptoms affected 22.4% (Italy), 48.8% (Lebanon), and 31.7% (Tunisia). General use of herbs was consistent (41.4-50.4%), with 23.3% (Italy), 50.2% (Lebanon), and 65.5% (Tunisia) employing herbs for COVID-19 therapy. Notably, in Lebanon, Za'atar, a thyme-like plant, correlated with reduced symptoms, suggesting potential protective effects that are likely due to its polyphenol richness. This study underscores the persistent reliance on traditional medicinal plants remedies in the Mediterranean area, with regional variations. Further exploration of herbal compounds for COVID-19-like symptoms is warranted.

Unraveling the metabolic activities of bioactive compounds on cellular models of hepatosteatosis and adipogenesis through docking analysis with PPARs

Obesity is associated with fatty liver disease. Available therapies show modest efficacy, and nutraceuticals with good effectiveness and safety are largely investigated. We focused on five natural compounds, three plant phenolic compounds (carvacrol, rosmarinic acid, silybin), and two thyroid hormones (T2: 3,5-diiodo-l-thyronine; T3: 3,5,3'-triiodo-L-thyronine) as comparison, to assess their beneficial effects on two cellular models of hepatosteatosis and adipogenesis. All compounds ameliorated the lipid accumulation and oxidative stress in both models, but with different potencies. The peroxisome proliferator-activated receptors (PPARs) are pivotal controllers of adipogenesis and lipid metabolism. For the main isoforms, PPARγ and PPARa, we assessed their possible binding to the compounds by molecular docking calculations, and their expression pattern by real-time PCR. All compounds bind both PPARs with different affinity, while not all compounds affect their expression. The results may clarify the distinctive molecular mechanisms underlying the action of the five compounds in the different cell models with possible applications to treat obesity.

Effects of Thymbra spicata extract and Thymol on morphine withdrawal syndrome in mice (insights to the liver function, antioxidant, and behavioral responses)

Safe chemicals for drug withdrawal can be extracted from natural sources. This study investigates the effects of clonidine and Thymbra spicata extract (TSE) on mice suffering from morphine withdrawal syndrome. Thymol, which is the active constituent in TSE, was also tested. A total of 90 mice were divided into nine groups. Group 1 was the control group, while Group 2 was given only morphine, and Group 3 received morphine and 0.2 mg/kg of clonidine. Groups 4-6 were given morphine along with 100, 200, and 300 mg/kg of TSE, respectively. Groups 7-9 received morphine plus 30, 60, and 90 mg/kg of Thymol, respectively, for 7 days. An oral naloxone challenge of 3 mg/kg was used to induce withdrawal syndrome in all groups. Improvement of liver enzyme levels (aspartate aminotransferase, alkaline phosphatase, and alanine transaminase) (p < .01) and behavioral responses (frequencies of jumping, frequencies of two-legged standing, Straub tail reaction) (p < .01) were significantly observed in the groups receiving TSE and Thymol (Groups 4-9) compared to Group 2. Additionally, antioxidant activity in these groups was improved compared to Group 2. Nitric oxide significantly decreased in Groups 4 and 6 compared to Groups 2 and 3 (p < .01). Superoxide dismutase increased dramatically in Groups 5, 8, and 9 compared to Groups 2 and 3 (p < .01). Groups 5-9 were significantly different from Group 2 in terms of malondialdehyde levels (p < .01). Certain doses of TSE and Thymol were found to alleviate the narcotics withdrawal symptoms. This similar effect to clonidine can pave the way for their administration in humans.

Comprehensive Strategies for Metabolic Syndrome: How Nutrition, Dietary Polyphenols, Physical Activity, and Lifestyle Modifications Address Diabesity, Cardiovascular Diseases, and Neurodegenerative Conditions

Several hallmarks of metabolic syndrome, such as dysregulation in the glucose and lipid metabolism, endothelial dysfunction, insulin resistance, low-to-medium systemic inflammation, and intestinal microbiota dysbiosis, represent a pathological bridge between metabolic syndrome and diabesity, cardiovascular, and neurodegenerative disorders. This review aims to highlight some therapeutic strategies against metabolic syndrome involving integrative approaches to improve lifestyle and daily diet. The beneficial effects of foods containing antioxidant polyphenols, intestinal microbiota control, and physical activity were also considered. We comprehensively examined a large body of published articles involving basic, animal, and human studie, as well as recent guidelines. As a result, dietary polyphenols from natural plant-based antioxidants and adherence to the Mediterranean diet, along with physical exercise, are promising complementary therapies to delay or prevent the onset of metabolic syndrome and counteract diabesity and cardiovascular diseases, as well as to protect against neurodegenerative disorders and cognitive decline. Modulation of the intestinal microbiota reduces the risks associated with MS, improves diabetes and cardiovascular diseases (CVD), and exerts neuroprotective action. Despite several studies, the estimation of dietary polyphenol intake is inconclusive and requires further evidence. Lifestyle interventions involving physical activity and reduced calorie intake can improve metabolic outcomes.

Nutritional and Physiological Properties of Thymbra spicata: In Vitro Study Using Fecal Fermentation and Intestinal Integrity Models

(Poly)phenolic-rich Mediterranean plants such as Thymbra spicata have been associated with several health-promoting effects. The nutritional value, as well as physiological interaction of T. spicata with the gastrointestinal tract, has not been investigated before. The nutritional composition of T. spicata leaves was here characterized by standard analytical methods. T. spicata leaves were subjected to ethanolic extraction, simulated gastrointestinal digestion, and anaerobic microbial gut fermentation. Phenols/flavonoid contents and radical scavenging activity were assessed by colorimetric methods. The volatile organic compounds (VOCs) were detected by gas chromatography coupled with mass spectrometry. The effect on intestinal integrity was evaluated using a Caco-2 monolayers mounted in a Ussing chamber. T. spicata contains a high amount of fiber (12.3%) and unsaturated fatty acids (76% of total fat). A positive change in VOCs including short-chain fatty acids was observed without significant change in viable microbe. T. spicata and carvacrol (main phenolic compound) enhanced ionic currents in a concentration-dependent manner without compromising the Caco-2 monolayer's integrity. These effects were partially lost upon simulated digestion and completely abolished after colonic fermentation in line with polyphenols and carvacrol content. Conclusion: T. spicata represents a promising nutrient for the modulation of gut microbiota and the gut barrier. Further studies must better define its mechanisms of action.

Chinese herbal medicines: The modulator of nonalcoholic fatty liver disease targeting oxidative stress

ETHNOPHARMACOLOGICAL RELEVANCE

Plants are a natural treasure trove; their secondary metabolites participate in several pharmacological processes, making them a crucial component in the synthesis of novel pharmaceuticals and serving as a reserve resource foundation in this process. Nonalcoholic fatty liver disease (NAFLD) is associated with the risk of progression to hepatitis and liver cancer. The "Treatise on Febrile Diseases," "Compendium of Materia Medica," and "Thousand Golden Prescriptions" have listed herbal remedies to treat liver diseases.

AIM OF THE REVIEW

Chinese herbal medicines have been widely used for the prevention and treatment of NAFLD owing to their efficacy and low side effects. The production of reactive oxygen species (ROS) during NAFLD, and the impact and potential mechanism of ROS on the pathogenesis of NAFLD are discussed in this review. Furthermore, common foods and herbs that can be used to prevent NAFLD, as well as the structure-activity relationships and potential mechanisms, are discussed.

METHODS

Web of Science, PubMed, CNKI database, Google Scholar, and WanFang database were searched for natural products that have been used to treat or prevent NAFLD in the past five years. The primary search was performed using the following keywords in different combinations in full articles: NAFLD, herb, natural products, medicine, and ROS. More than 400 research papers and review articles were found and analyzed in this review.

RESULTS

By classifying and discussing the literature, we obtained 86 herbaceous plants, 28 of which were derived from food and 58 from Chinese herbal medicines. The mechanism of NAFLD was proposed through experimental studies on thirteen natural compounds (quercetin, hesperidin, rutin, curcumin, resveratrol, epigallocatechin-3-gallate, salvianolic acid B, paeoniflorin, ginsenoside Rg1, ursolic acid, berberine, honokiol, emodin). The occurrence and progression of NAFLD could be prevented by natural antioxidants through several pathways to prevent ROS accumulation and reduce hepatic cell injuries caused by excessive ROS.

CONCLUSION

This review summarizes the natural products and routinely used herbs (prescription) in the prevention and treatment of NAFLD. Firstly, the mechanisms by which natural products improve NAFLD through antioxidant pathways are elucidated. Secondly, the potential of traditional Chinese medicine theory in improving NAFLD is discussed, highlighting the safety of food-medicine homology and the broader clinical potential of multi-component formulations in improving NAFLD. Aiming to provide theoretical basis for the prevention and treatment of NAFLD.

Polyphenol-enriched extracts of Sarcopoterium spinosum fruits for counteracting lipid accumulation and oxidative stress in an in vitro model of hepatic steatosis

Sarcopoterium spinosum (L.) Spach is a Rosaceae shrub employed in the folk medicine in the Eastern Mediterranean basin. The previous few studies have focused on the S. spinosum roots, while the fruits have been poorly investigated. The present study aims to assess the biological properties of S. spinosum fruits collected in Lebanon and subjected to ethanolic, water or boiling water extraction. The extracts were compared for the phenol and flavonoid contents, and for the in vitro radical scavenging ability. The ethanolic extract (SEE) was selected and characterized by high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS) showing a phenolome rich in tannins (ellagitannins), flavonoids (quercetin derivatives), and triterpenes. The biological activity of SEE was tested on a cellular model of moderate steatosis consisting of lipid-loaded hepatic cells treated with increasing concentrations of SEE (1-25 μg/mL), or with corilagin or quercetin as comparison. In steatotic hepatocytes the SEE was able (i) to ameliorate the hepatosteatosis; (ii) to counteract the excess ROS and lipid peroxidation; (iii) to restore the impaired catalase activity. The results indicate that the ethanolic extract from S. spinosum fruits is endowed with relevant antisteatotic and antioxidant activities and might find application as nutraceutical product.

Oxidative Stress and MicroRNAs in Endothelial Cells under Metabolic Disorders

Reactive oxygen species (ROS) are radical oxygen intermediates that serve as important second messengers in signal transduction. However, when the accumulation of these molecules exceeds the buffering capacity of antioxidant enzymes, oxidative stress and endothelial cell (EC) dysfunction occur. EC dysfunction shifts the vascular system into a pro-coagulative, proinflammatory state, thereby increasing the risk of developing cardiovascular (CV) diseases and metabolic disorders. Studies have turned to the investigation of microRNA treatment for CV risk factors, as these post-transcription regulators are known to co-regulate ROS. In this review, we will discuss ROS pathways and generation, normal endothelial cell physiology and ROS-induced dysfunction, and the current knowledge of common metabolic disorders and their connection to oxidative stress. Therapeutic strategies based on microRNAs in response to oxidative stress and microRNA's regulatory roles in controlling ROS will also be explored. It is important to gain an in-depth comprehension of the mechanisms generating ROS and how manipulating these enzymatic byproducts can protect endothelial cell function from oxidative stress and prevent the development of vascular disorders.

The Impact of Za'atar Antioxidant Compounds on the Gut Microbiota and Gastrointestinal Disorders: Insights for Future Clinical Applications

Since the gut microbiota plays a pivotal role in host homeostasis and energy balance, changes in its composition can be associated with disease states through the promotion of immune-mediated inflammatory disorders and increasing intestinal permeability, ultimately leading to the impairment of intestinal barrier function. Za'atar is one of the most popular plant-based foods in the Eastern Mediterranean region. Za'atar is a mixture of different plant leaves, fruits, and seeds and contains hundreds of antioxidant compounds, especially polyphenols, and fiber, with pre-clinical and clinical evidence suggesting health-promoting effects in cardiovascular and metabolic disease. Za'atar compounds have also been studied from a gastrointestinal perspective, concerning both gut microbiota and gastrointestinal diseases. Antioxidants such as Za'atar polyphenols may provide beneficial effects in the complex interplay between the diet, gut microbiota, and intestinal permeability. To our knowledge, no studies have reported the effects of the whole Za'atar mixture, however, based on the pre-clinical studies published on components and single compounds found in Za'atar, we provide a clinical overview of the possible effects on the gastrointestinal tract, focusing mainly on carvacrol, rosmarinic acid, gallic acid, and other polyphenols. We also cover the potential clinical applications of Za'atar mixture as a possible nutraceutical in disorders involving the gastrointestinal tract.

Influence of Simulated In Vitro Gastrointestinal Digestion on the Phenolic Profile, Antioxidant, and Biological Activity of Thymbra spicata L. Extracts

Plants or plant extracts are widely investigated for preventing/counteracting several chronic disorders. The oral route is the most common route for nutraceutical and drug administration. Currently, it is still unclear as to whether and how the pattern of phenolic compounds (PCs) found in the plants as well as their bioactivity could be modified during the gastrointestinal transit. Recent studies have revealed antioxidant and anti-steatotic properties of Thymbra spicata. Here, we investigated the possible loss of phytochemicals that occurs throughout the sequential steps of a simulated in vitro gastrointestinal (GI) digestion of aqueous and ethanolic extracts of aerial parts of T. spicata. Crude, digested, and dialyzed extracts were characterized in terms of their phenolic profile and biological activities. Total contents of carbohydrates, proteins, PCs, flavonoids, and hydroxycinnamic acids were quantified. The changes in the PC profile and in bioactive compounds upon the simulated GI digestion were monitored by HPLC-MS/MS analysis. The antioxidant activity was measured by different spectrophotometric assays, and the antiproliferative potential was assessed by using three representative human cancer cell lines. We observed that the simulated GI digestion reduced the phytochemical contents in both aqueous and ethanolic T. spicata extracts and modified the PC profile. However, T. spicata extracts improved their antioxidant potential after digestion, while a partial reduction in the antiproliferative activity was observed for the ethanolic extract. Therefore, our results could provide a scientific basis for the employment of T. spicata extract as valuable nutraceutical.

Beneficial Effects of Carvacrol on In Vitro Models of Metabolically-Associated Liver Steatosis and Endothelial Dysfunction: A Role for Fatty Acids in Interfering with Carvacrol Binding to Serum Albumin

BACKGROUND

Carvacrol, a plant phenolic monoterpene, is largely employed as food additive and phytochemical.

OBJECTIVE

We aimed to assess the lipid lowering and protective effects of carvacrol in vitro using cellular models of hepatic steatosis and endothelial dysfunction. We also investigated if and how the binding of carvacrol to albumin, the physiological transporter for small compounds in the blood, might be altered by the presence of high levels of fatty acids (FAs).

METHODS

Hepatic FaO cells treated with exogenous FAs mimic hepatosteatosis; endothelial HECV cells exposed to hydrogen peroxide are a model of endothelial dysfunction. In these models, we measured spectrophotometrically lipid accumulation and release, lipoperoxidation, free radical production, and nitric oxide release before and after treatment with carvacrol. The carvacrol binding to albumin in the presence or absence of high levels of FAs was assessed by absorption and emission spectroscopies.

RESULTS

Carvacrol counteracted lipid accumulation and oxidative stress in hepatocytes and protected endothelial cells from oxidative stress and dysfunction. Moreover, high levels of FAs reduced the binding of carvacrol to albumin.

CONCLUSION

The results suggest the good potential of carvacrol in ameliorating dysfunction of hepatic and endothelial cells in vitro. High levels of circulating FAs might compete with carvacrol for binding to albumin thus influencing its transport and bio-distribution.

The Potential of Lamiaceae Herbs for Mitigation of Overweight, Obesity, and Fatty Liver: Studies and Perspectives

Numerous plants, plant extracts, and plant-derived compounds are being explored for their beneficial effects against overweight and liver diseases. Obesity is associated with the increased prevalence of non-alcoholic fatty liver disease (NAFLD), becoming the most common liver disease in Western countries. Obesity and NAFLD are closely associated with many other metabolic alternations such as insulin resistance, diabetes mellitus, and cardiovascular diseases. Many herbs of the Lamiaceae family are widely employed as food and spices in the Mediterranean area, but also in folk medicine, and their use for the management of metabolic disorders is well documented. Hereby, we summarized the scientific results of the medicinal and nutraceutical potential of plants from the Lamiaceae family for prevention and mitigation of overweight and fatty liver. The evidence indicates that Lamiaceae plants may be a cost-effective source of nutraceuticals and/or phytochemicals to be used in the management of metabolic-related conditions such as obesity and NAFLD. PubMed, Google Scholar, Scopus, and SciFinder were accessed to collect data on traditional medicinal plants, compounds derived from plants, their reported anti-obesity mechanisms, and therapeutic targets.

The Antioxidant and Hypolipidemic Effects of Mesona Chinensis Benth Extracts

In this study, the antioxidant and hypolipidemic effects of Mesona Chinensis Benth (MCB) extracts were evaluated. Seven fractions (F0, F10, F20, F30, F40, F50 and MTF) were obtained from the MCB ethanol extracts. Compared to the commercial antioxidants (vitamin C), MTF and F30 exhibited higher antioxidant activities in the antiradical activity test and the FRAP assay. The half-inhibition concentration (IC50) for MTF and F30 were 5.323 µg/mL and 5.278 µg/mL, respectively. MTF at 200 µg/mL significantly decreased the accumulation of TG in oleic acid (OA)-induced HepG2 cells and reversed the inhibitory effect of Compound C on AMPK (MTF and F30 significantly increased the glucose utilization of insulin-induced HepG2 cells). In addition, the components of MTF were identified by HPLC-MS, which were caffeic acid, quercetin 3-O-galactoside, isoquercetin, astragalin, rosmarinic acid, aromadendrin-3-O-rutinoside, rosmarinic acid-3-O-glucoside and kaempferol-7-O-glucoside. Through statistical correlations by Simca P software, it was found that the main antioxidant and hypolipidemic components of MCB might be caffeic acid, kaempferol-7-O-glucoside, rosmarinic acid-3-O-glucoside and aromadendrin-3-O-rutinoside, which may play important roles in the AMPK pathway. MTF and F30 in MCB could be potential health products for the treatment of hyperlipidemia.

In vitro antiviral activity of Thymbra spicata L. extract on bovine respiratory viruses (BCoV, BPIV-3, BRSV, BVDV and BoHV-1)

AIMS

Viral pathogens are the primary agents in bovine respiratory disease cases, and there is no direct effective antiviral drug application. Thymbra is a genus of oregano commonly found in Turkey. The primary component (34.9%) of the extract obtained from Thymbra spicata L. is the carvacrol which is used in traditional medicine. This study evaluates the potential antiviral activity and inactivation efficiency of T. spicata L. extract against bovine respiratory viruses, including BCoV, BPIV-3, BRSV, BVDV and BoHV-1.

METHODS AND RESULTS

To evaluate its effect on viral replication, viral titres were taken from infected cells treated with non-cytotoxic T. spicata L. extract concentrations (0.75% and 1.5%, 1.32 and 2.64 µg/ml of carvacrol as active ingredient, respectively) and compared to non-treated infected cells. The viruses were treated directly with 1.5% T. spicata L. extract, and the viral titres were evaluated at certain time points to determine the efficiency of direct inactivation. The number of infectious virions for BCoV, BPIV-3, BRSV, BVDV and BoHV-1 treated with 1.5% T. spicata L. extract were decreased by 99.44%, 100.0%, 94.38%, 99.97% and 99.87%, respectively.T. spicata L. extract strongly inhibits the replication of mentioned viruses in a dose-dependent manner in vitro. In addition, T. spicata L. extract shared direct inactivation efficiency on the mentioned viruses in a time-dependent manner.

CONCLUSION

This study shows the antiviral efficiency of T. spicata L. on BRD-related viral agents for the first time. The oregano species T. spicata and its main component, carvacrol, may have a potential for antiviral activity in the alternative treatment of respiratory viral diseases in cattle.

SIGNIFICANCE AND IMPACT OF THE STUDY

Given the similarity of replication strategies, obtained data suggest the possible efficiency of T. spicata L. on human respiratory viruses.

Repressive effect of Rhus coriaria L. fruit extracts on microglial cells-mediated inflammatory and oxidative stress responses

ETHNOPHARMACOLOGICAL RELEVANCE

Rhus coriaria L. represents a herbal shrub that is used widely in traditional medicine in the Middle East region to treat different diseases including inflammation-related disorders. R. coriaria extracts have been well characterized in terms of their biological activities, pharmacological potential and phytochemical components. However, the effect of R. coriaria on neuro-inflammation has not been studied previously in detail.

AIM OF THE STUDY

In the present study, we performed a qualitative phytochemical analysis and investigated the antioxidant and anti-neuro-inflammatory potential of R. coriaria extracts on BV-2 microglial cells.

MATERIALS AND METHODS

R. coriaria extracts were prepared using two different solvents: distilled water and ethanol. Phytochemical screening was performed to determine the principal bioactive components. The radical scavenging activity was assessed by DPPH method (2,2-diphenyl-1-picrylhydrazyl). The effect of R. coriaria on neuro-inflammation was studied upon measuring the production of oxidative stress and inflammatory factors using DCF (2',7'-dichlorofluorescein) and Nitric oxide (NO) assays respectively, and by analyzing the mRNA (TNFα, IL-10, iNOS and COX-2) and protein (NFκβ) levels of genes involved BV-2 microglia cells-mediated inflammation using quantitative Real Time PCR and Western blot, respectively.

RESULTS

We found that R. coriaria extracts contain high phenolic and flavonoid contents. Interestingly, the ethanolic extract exerted a potent anti-inflammatory potential on insulted BV-2 cells manifested by: i) inhibition of Reactive Oxygen species (ROS) production and nitric oxide (NO) release; ii) suppressing TNFα, iNOS and COX-2 mRNA levels; iii) reducing NFκβ activation; and iiii) enhancing IL-10 transcription levels.

CONCLUSION

Our results indicate that the neuro-inflammation inhibitory activity of R. coriaria extracts involves the inhibition of NF-κB signaling pathway. These findings suggest that R. coriaria might carry therapeutic potential against neurodegenerative diseases.

Dietary Polyphenols and Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD), which is emerging as a major public health issue worldwide, is characterized by a wide spectrum of liver disorders, ranging from simple fat accumulation in hepatocytes, also known as steatosis, to non-alcoholic steatohepatitis (NASH) and cirrhosis. At present, the pharmacological treatment of NAFLD is still debated and dietary strategies for the prevention and the treatment of this condition are strongly considered. Polyphenols are a group of plant-derived compounds whose anti-inflammatory and antioxidant properties are associated with a low prevalence of metabolic diseases, including obesity, hypertension, and insulin resistance. Since inflammation and oxidative stress are the main risk factors involved in the pathogenesis of NAFLD, recent studies suggest that the consumption of polyphenol-rich diets is involved in the prevention and treatment of NAFLD. However, few clinical trials are available on human subjects with NAFLD. Here, we reviewed the emerging existing evidence on the potential use of polyphenols to treat NAFLD. After introducing the physiopathology of NAFLD, we focused on the most investigated phenolic compounds in the setting of NAFLD and described their potential benefits, starting from basic science studies to animal models and human trials.

Adipocyte hypertrophy parallels alterations of mitochondrial status in a cell model for adipose tissue dysfunction in obesity

AIMS

Adipocyte hypertrophy is the main cause of obesity. A deeper understanding of the molecular mechanisms regulating adipocyte dysfunction may help to plan strategies to treat/prevent obesity and its metabolic complications. Here, we investigated in vitro the molecular alterations associated with early adipocyte hypertrophy, focusing on mitochondrial dysfunction.

MAIN METHODS

As model of adipocyte hypertrophy, we employed 3T3-L1 preadipocytes firstly differentiated into mature adipocytes, then cultured with long-chain fatty acids. As a function of differentiation and hypertrophy, we assessed triglyceride content, lipid droplet size, radical homeostasis by spectrophotometry and microscopy, as well as the expression of PPARγ, adiponectin and metallothioneins. Mitochondrial status was investigated by electron microscopy, oxygraph 2 k (O2K) high-resolution respirometry, fluorimetry and western blot.

KEY FINDINGS

Compared to mature adipocytes, hypertrophic adipocytes showed increased triglyceride accumulation and lipid peroxidation, larger or unique lipid droplet, up-regulated expression of PPARγ, adiponectin and metallothioneins. At mitochondrial level, early-hypertrophic adipocytes exhibited: (i) impaired mitochondrial oxygen consumption with parallel reduction in the mitochondrial complexes; (ii) no changes in citrate synthase and HSP60 expression, and in the inner mitochondrial membrane polarization; (iii) no stimulation of mitochondrial fatty acid oxidation. Our findings indicate that the content, integrity, and catabolic activity of mitochondria were rather unchanged in early hypertrophic adipocytes, while oxygen consumption and oxidant production were altered.

SIGNIFICANCE

In the model of early adipocyte hypertrophy exacerbated oxidative stress and impaired mitochondrial respiration were observed, likely depending on reduction in the mitochondrial complexes, without changes in mitochondrial mass and integrity.

Protective effects of extracts from Ephedra foeminea Forssk fruits against oxidative injury in human endothelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Ephedra foeminea is a member of the Ephedraceae family which is widespread in the eastern Mediterranean area. In Lebanon, Ephedra is a popular remedy in traditional medicine to prevent and/or counteract many stress oxidative-related diseases like inflammation and bacterial infections.

AIM OF THE STUDY

Oxidative stress leads to endothelial cell dysfunction, and is a major factor contributing to etiology of atherosclerosis and related diseases. This study aims to investigate the antioxidant and cytoprotective potential of extracts from E. foeminea fruits on human endothelial cells exposed to hydrogen peroxide (H₂O₂) to mimic in vitro vascular endothelium dysfunction.

MATERIALS AND METHODS

Different extracts of E. foeminea fruits were prepared using pure ethanol (EE), methanol/water (EMW), pure hexane (Ehex) or ethyl acetate/water (Epoly) as extraction solvents. The phenolome profile of each extract was characterized using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS). Total phenolic and flavonoid content, and radical scavenging properties of the extracts were assessed spectrophotometrically. Then, the effects on human endothelial cells HECV were evaluated.

RESULTS

Epoly extract showed the highest phenol and flavonoid content, and the highest radical scavenging capacity. On H₂O₂-insulted HECV cells Epoly was able: (i) to counteract the ROS/RNS production and lipid peroxidation; (ii) to rescue the ROS-dependent decrease in the mitochondrial membrane potential; (iii) to counteract the apoptosis induction; (iv) to restore endothelial cell viability and migration.

CONCLUSIONS

The findings indicated that the polyphenol-enriched extract Epoly from E. foeminea fruits is endowed with in vitro anti-oxidant and anti-apoptotic effects and might be used as nutraceutical for treating ROS-related endothelium dysfunction and inflammation.

New Perspectives of S-Adenosylmethionine (SAMe) Applications to Attenuate Fatty Acid-Induced Steatosis and Oxidative Stress in Hepatic and Endothelial Cells

S-adenosylmethionine (SAMe) is an endogenous methyl donor derived from ATP and methionine that has pleiotropic functions. Most SAMe is synthetized and consumed in the liver, where it acts as the main methylating agent and in protection against the free radical toxicity. Previous studies have shown that the administration of SAMe as a supernutrient exerted many beneficial effects in various tissues, mainly in the liver. In the present study, we aimed to clarify the direct effects of SAMe on fatty acid-induced steatosis and oxidative stress in hepatic and endothelial cells. Hepatoma FaO cells and endothelial HECV cells exposed to a mixture of oleate/palmitate are reliable models for hepatic steatosis and endothelium dysfunction, respectively. Our findings indicate that SAMe was able to significantly ameliorate lipid accumulation and oxidative stress in hepatic cells, mainly through promoting mitochondrial fatty acid entry for β-oxidation and external triglyceride release. SAMe also reverted both lipid accumulation and oxidant production (i.e., ROS and NO) in endothelial cells. In conclusion, these outcomes suggest promising beneficial applications of SAMe as a nutraceutical for metabolic disorders occurring in fatty liver and endothelium dysfunction.

Antitumor Activity of Ethanolic Extract from Thymbra Spicata L. aerial Parts: Effects on Cell Viability and Proliferation, Apoptosis Induction, STAT3, and NF-kB Signaling

Thyme-like plants including Thymbra spicata L. are widely used as food and folk medicinal remedies in the Mediterranean area. This study aimed to explore the in vitro antitumor potential of polyphenol-enriched extracts from aerial parts of T. spicata. The ethanolic extract significantly inhibited proliferation of different human tumor cell lines, without significant effects on non-neoplastic cells. A deeper investigation of the molecular mechanism sustaining the in vitro antitumor activity of the extract was carried on the human breast cancer cells MCF-7 in comparison with the normal breast cells MCF-10A. The effects on MCF-7 cells were associated with the following: (i) production of reactive oxygen species (ROS) and release of nitric oxide; (ii) apoptosis induction; and (iii) reduction in STAT3 and NF-kB phosphorylation. The ethanolic extract from T. spicata leaves might represent a novel therapeutic tool in combination with conventional chemotherapy to reduce the adverse side effects and drug resistance.

The Impacts of Herbal Medicines and Natural Products on Regulating the Hepatic Lipid Metabolism

The dysregulation of hepatic lipid metabolism is one of the hallmarks in many liver diseases including alcoholic liver diseases (ALD) and non-alcoholic fatty liver diseases (NAFLD). Hepatic inflammation, lipoperoxidative stress as well as the imbalance between lipid availability and lipid disposal, are direct causes of liver steatosis. The application of herbal medicines with anti-oxidative stress and lipid-balancing properties has been extensively attempted as pharmaceutical intervention for liver disorders in experimental and clinical studies. Although the molecular mechanisms underlying their hepatoprotective effects warrant further exploration, increasing evidence demonstrated that many herbal medicines are involved in regulating lipid accumulation processes including hepatic lipolytic and lipogenic pathways, such as mitochondrial and peroxisomal β-oxidation, the secretion of very low density lipoprotein (VLDL), the non-esterified fatty acid (NEFA) uptake, and some vital hepatic lipogenic enzymes. Therefore, in this review, the pathways or crucial mediators participated in the dysregulation of hepatic lipid metabolism are systematically summarized, followed by the current evidences and advances in the positive impacts of herbal medicines and natural products on the lipid metabolism pathways are detailed. Furthermore, several herbal formulas, herbs or herbal derivatives, such as Erchen Dection, Danshen, resveratrol, and berberine, which have been extensively studied for their promising potential in mediating lipid metabolism, are particularly highlighted in this review.

Aquaporin-9 is involved in the lipid-lowering activity of the nutraceutical silybin on hepatocytes through modulation of autophagy and lipid droplets composition

Hepatic steatosis is the hallmark of non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of the metabolic syndrome and insulin resistance with potential evolution towards non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. Key roles of autophagy and oxidative stress in hepatic lipid accumulation and NAFLD progression are recognized. Here, we employed a rat hepatoma cell model of NAFLD progression made of FaO cells exposed to oleate/palmitate followed or not by TNFα treatment to investigate the molecular mechanisms through which silybin, a lipid-lowering nutraceutical, may improve hepatic lipid dyshomeostasis. The beneficial effect of silybin was found to involve amelioration of the fatty acids profile of lipid droplets, stimulation of the mitochondrial oxidation and upregulation of a microRNA of pivotal relevance in hepatic fat metabolism, miR-122. Silybin was also found to restore the levels of Aquaporin-9 (AQP9) and glycerol permeability while reducing the activation of the oxidative stress-dependent transcription factor NF-κB, and autophagy turnover. In conclusion, silybin was shown to have molecular effects on signaling pathways that were previously unknown and potentially protect the hepatocyte. These actions intersect TG metabolism, fat-induced autophagy and AQP9-mediated glycerol transport in hepatocytes.