Comparative Study between Extracts of Different Pomegranate Parts Issued from Five Tunisian Cultivars (Punica granatum L.): Phytochemical Content, Volatile Composition and Biological Activity

Very few studies are interested to the volatile compounds of pomegranate and evoking their potentials, especially, their antibacterial activity. In the present study, edible (arils) and non-edible (peels) parts of five pomegranate varieties (Tounsi, Kalai, Zahri, Chelfi and Garci) were compared for their phenolic contents, antioxidant activity, aroma profile and antibacterial propriety of their volatile compounds. Results showed that peel of the five varieties contained higher content in phenolics, flavonoids, tannins, anthocyanins and carotenoids additionally to higher antioxidant power. Considerable correlations have been highlighted between polyphenols, o-diphenols and flavonoids of peel extracts and the DPPH scavenging activity as well as reducing power. Concerning volatile compounds, Chelfi is quantitatively the richest cultivar. However, the Tounsi seems to be quantitatively the richest for both peels and arils. Gram positive bacteria were more sensitive to volatiles extract than gram negative with a substantial activity of both peel and seed extracts of Tounsi variety. It’s therefore tempting to speculate that the non-edible part (peel) has a therapeutic and nutritional potential that must be valorised

Growth Inhibitory and Pro-Apoptotic Effects of Ornamental Pomegranate Extracts in Du145 Human Prostate Cancer Cells

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Mitochondrial dysfunction, oxidative stress and apoptotic induction in microglial BV-2 cells treated with sodium arsenate.

International audienceThe treatment of microglial BV-2 cells with sodium arsenate (As(V): 0.1-400μmol/L - 48hr) induces a dose-dependent response. The neurotoxic effects of high concentrations of As(V) (100, 200 and 400μmol/L) are characterized by increased levels of mitochondrial complexes I, II, and IV followed by increased superoxide anion generation. Moreover, As(V) triggers an apoptotic mode of cell death, demonstrated by an apoptotic SubG1 peak, associated with an alteration of plasma membrane integrity. There is also a decrease in transmembrane mitochondrial potential and mitochondrial adenosine triphosphate ATP. It is therefore tempting to speculate that As(V) triggers mitochondrial dysfunction, which may lead to defective oxidative phosphorylation subsequently causing mitochondrial oxidative damage, which in turn induces an apoptotic mode of cell death

Evidence of hormesis on human neuronal SK-N-BE cells treated with sodium arsenate: impact at the mitochondrial level.

International audienceExposure of human neuronal SK-N-BE cells to sodium arsenate (AsV 0.1-400 μM; 48 h) induced a biphasic toxic effect evoking hormesis. Indeed, at low concentrations, AsV stimulates cell proliferation visualized by phase contrast microscopy, whereas at high concentrations, an induction of cell death associated with a loss of cell adhesion was observed. These side effects were confirmed with crystal violet test, cell cycle analysis, evaluation of the percentage of Ki67 positive cells, and staining with propidium iodide. The impact of AsV on mitochondrial functions, which was determined by the MTT assay, the measurement of mitochondrial transmembrane potential with DiOC6(3), and the rate of mitochondrial ATP, also support an hormesis process. In addition, in the presence of high concentrations of AsV, a significant decrease of the protein expression of OXPHOS complexes of the respiratory chain was observed by western blot supporting that AsV-induced cell death is associated with mitochondrial alterations. Therefore, there are some evidences of hormesis on AsV-treated SK-N-BE cells, and at high concentrations, the mitochondria are a target of toxicity induced by AsV

Association of plasma fatty acid alteration with the severity of coronary artery disease lesions in Tunisian patients

Abstract Background Some factors related to diet are known to be involved in the progression of atherosclerosis in humans. Methods The relationship between plasma fatty acid (FA) levels and the severity of coronary artery disease (CAD), evaluated by Gensini score (GS), was investigated in CAD Tunisian patients compared to controls. Lipid profiles were analyzed, GS was calculated in CAD and non-CAD patients and compared to controls. Results CAD patients showed an alteration of conventional lipid parameters. In fact, a significant increase of plasmatic triglycerides (TG) level, atherogenic lipid ratios (TC/HDL-C,TG/HDL-C, LDL-C/HDL-C); and ApoB/ApoA1 was observed in the CAD group comparatively to controls (p < 0.001). Gensini score was showed to be a good indicator to evaluate cholesterol metabolism disorders associated with HDL-C since a negative association was found between HDL-C levels and GS for the two groups of patients. In addition, in the relation with FA and classes of FA, a negative association was found as expected, between Gensini score and total MUFA, PUFA n-3, total PUFA, GLA, DGLA and DHA. Furthermore, a positive association with stearic and erucic acid was found. Suggests that, GS is also a good indicator to evaluate FA metabolic disorders. Higher elongation index and modifications of desaturation index (D5D, D6D and D9D) were observed in patients compared to controls, supporting FA metabolism modifications. Conclusions In conclusion, although that Tunisian population appears to follow the Mediterranean diet, variations of plasmatic FA levels and desaturase activities in CAD patients highlights an alteration of FA metabolism and suggests an important implication of certain FA in the development of atherosclerosis

Correlation of trans fatty acids with the severity of coronary artery disease lesions

Abstract Background Nutritional choices, which include the source of dietary fatty acids (FA), have an important significant impact on coronary artery disease (CAD). We aimed to determine on patients with CAD the relationships between Trans fatty acids (Trans FA) and different CAD associated parameters such as inflammatory and oxidative stress parameters in addition to Gensini score as a vascular severity index. Methods Fatty acid profiles were established by gas chromatography from 111 CAD patients compared to 120 age-matched control group. Lipid peroxidation biomarkers, oxidative stress, inflammatory parameters and Gensini score were studied. Results Our study showed a significant decrease of the antioxidant parameters levels such as erythrocyte glutathione peroxydase (GPx) and superoxide dismutase (SOD) activities, plasma antioxidant status (FRAP) and thiol (SH) groups in CAD patients. On the other hand, catalase activity, conjugated dienes and malondialdehyde were increased. Plasmatic and erythrocyte Trans FA were also increased in CAD patients compared to controls. Furthermore, divergent associations of these Trans FA accumulations were observed with low-density lipoprotein-cholesterol/ high-density lipoprotein-cholesterol (LDL-C/HDL-C) ratio, Apolipoprotein B (ApoB), lipid peroxidation parameters, high-sensitivity C Reactive Protein (hs-CRP), Interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and Gensini score. Especially, elaidic acid (C18:1 trans 9), trans C18:2 isomers and trans 11 eicosanoic acid are correlated with these parameters. Trans FA are also associated with oxidative stress, confirmed by a positive correlation between C20:1 trans 11 and GPx in erythrocytes. Conclusions High level of Trans FA was highly associated with the induction of inflammation, oxidative stress and lipoperoxidation which appear to be based on the vascular severity and might be of interest to assess the stage and progression of atherosclerosis. The measurement of these Trans FA would be of great value for the screening of lipid metabolism disorders in CAD patients

COVID-19 in Tunisia (North Africa): Seroprevalence of SARS-CoV-2 in the general population of the capital city Tunis

International audienceBackground: Monitoring the coronavirus disease-19 (COVID-19) pandemic is primarily based on Reverse transcription polymerase chain reaction (RT PCR) detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As this test is mainly applied on persons with symptomatic disease, it may overlook individuals with pauci- or a-symptomatic infection. Seroprevalence studies are thus essential to get an accurate estimate of the actual SARS-CoV-2 diffusion within the populations. We report on the findings of the first serosurvey conducted in the capital city of Tunisia prior to the implementation of mass vaccination and analyzed factors associated with seropositivity. Methods: A cross sectional survey was conducted among households living in two areas of the governorate of Tunis, the capital city of the country. The survey was realized between March and April 2021, spanning the end of the second wave and the beginning of the third wave of COVID-19 and prior to the implementation of mass vaccination in Tunisia. SARS-CoV-2 specific immunoglobulin G (IgG) antibodies to the spike (S-RBD) or the nucleocapsid (N) proteins were detected using an in-house ELISA test. Results were adjusted for test performance. Multivariate logistic regression analysis was performed to determine factors independently associated with SARS-COV-2 seropositivity. Results: The survey included 1676 individuals from 431 households. The mean age and sex ratio were 43.3±20.9 years and 0.6 respectively. The weighted and test-performance adjusted prevalence of IgG antibodies to the N and the S-RBD proteins were 26.6% [22.9-30.8] and 25.1% [22.2-28.4] respectively. The weighted seroprevalence of anti-N and/or anti-S-RBD IgG antibodies was equal to 38.0% [34.6-41.5]. In multivariate analysis, age under 10, no tobacco use, previous diagnosis of COVID-19, a history of COVID-19 related symptoms and contact with a COVID-19 case within the household, were independently associated with higher SARS-CoV-2 seroprevalence. Conclusions: After the end of the second epidemic wave, more than one third of people living in Tunis got antibodies to SARS-CoV-2. Further studies are needed to monitor changes in these figures as Tunisian population is confronted to the subsequent epidemic waves and to guide the vaccine strategy

COVID-19 in Tunisia (North Africa): Seroprevalence of SARS-CoV-2 in the General Population of the Capital City Tunis

Seroprevalence studies are essential to get an accurate estimate of the actual SARS-CoV-2 diffusion within populations. We report on the findings of the first serosurvey conducted in Tunis prior to the implementation of mass vaccination and analyzed factors associated with seropositivity. A household cross sectional survey was conducted (March&ndash;April 2021) in Tunis, spanning the end of the second wave and the beginning of the third wave of COVID-19. SARS-CoV-2 specific immunoglobulin G (IgG) antibodies to the spike (S-RBD) or the nucleocapsid (N) proteins were detected by in-house ELISA tests. The survey included 1676 individuals from 431 households. The mean age and sex ratio were 43.3 &plusmn; 20.9 years and 0.6, respectively. The weighted seroprevalence of anti-N and/or anti-S-RBD IgG antibodies was equal to 38.0% (34.6&ndash;41.5). In multivariate analysis, age under 10, no tobacco use, previous diagnosis of COVID-19, a history of COVID-19 related symptoms and contact with a COVID-19 case within the household, were independently associated with higher SARS-CoV-2 seroprevalence. More than one third of people living in Tunis obtained antibodies to SARS-CoV-2. Further studies are needed to monitor changes in these figures as Tunisian population is confronted to the subsequent epidemic waves and to guide the vaccine strategy