Ons Boudawara

Biological properties of Alsidium corallinum and its potential protective effects against damage caused by potassium bromate in the mouse liver

In the course of searching for hepatoprotective agents from natural sources, the protective effect of chemical constituents of the marine red alga Alsidium corallinum (A. corallinum) against potassium bromate (KBrO3)-induced liver damage in adult mice was investigated. The in vitro antioxidant and antibacterial properties of A. corallinum were firstly investigated. Then, A. corallinum was tested in vivo for its potential protective effects against damage caused by KBrO3 in mice models divided into four groups: controls, KBrO3, KBrO3 + A. corallinum, and A. corallinum. Our results demonstrated the rich composition of A. corallinum in antioxidant compounds like phenolics, flavonoids, anthocyanins, polysaccharides, chlorophyll and carotenoids. Its antioxidant activity was also confirmed using β-carotene bleaching by linoleic acid assay, reducing sugar test and trolox equivalent antioxidant capacity. The ethanolic extract of A. corallinum also showed good inhibition of the tested bacteria. The coadministration of the red alga associated to the KBrO3 alleviated hepatotoxicity as monitored by the improvement of hepatic oxidative stress biomarkers and plasma biochemical parameters, when compared to the KBrO3-treated mice. These results were confirmed by the improvement of histological and molecular changes. Treatment with A. corallinum prevented liver damage induced by KBrO3, thus protecting the body against free radicals and reducing inflammation and hypercholesterolemia risks.

Expression of metallothioneins I and II related to oxidative stress in the liver of aluminium-treated rats

Abstract Hepatotoxicity, induced by aluminium chloride (AlCl3), has been well studied but there are no reports about liver metallothionein (MT) genes induction. Therefore, it is of interest to establish the mechanism involving the relation between MT gene expression levels and the oxidative stress status in hepatic cells of aluminium-treated rats. Aluminium (Al) was administered to rats in their drinking water at a dose of 50 mg/kg body weight for three weeks. AlCl3 provoked hepatotoxicity objectified by an increase in malondialdehyde (MDA), hydrogen peroxide (H2O2), advanced oxidation protein products (AOPP), protein carbonyls (PCO) and a decrease in reduced glutathione (GSH), non-protein thiols (NPSH) and vitamin C. CAT and Glutathione peroxidase (GPx) activities were decreased while Mn-SOD gene expression, total Metallothionein content and MT I and MT II genes induction were increased. There are changes in plasma of some trace elements, albumin levels, transaminases, LDH and ALP activities. All these changes were supported by histopathological observations.

Methyl thiophanate-induced toxicity in liver and kidney of adult rats: a biochemical, molecular and histopathological approach

The aim of this study was to elucidate the redox effects of Thiophanate methyl (MT) in the rat liver and kidney. Our results showed, after 3 days of MT injection (700 mg/kg), an increase in malondialdehyde (MDA), hydrogen peroxide and advanced oxidation protein products levels. Glutathione peroxidase and superoxide dismutase activities were also remarkably increased in the liver but decrease in the kidney. Glutathione and vitamin C values were significantly reduced. The changes in biochemical parameters were substantiated by histological and molecular data. A smear without ladder formation on agarose gel was shown, indicating random DNA degradation in the liver and the kidney of MT treated rats. The increase in cyclooxygenase-2 gene expression, marker of inflammation, and an increase in genes expression of glutathione peroxidase and superoxide dismutase in liver and their decrease in the kidney were also occurred after MT exposure. These data confirmed the pro-oxidant and genotoxic effects of this fungicide.

Altered hepatic mRNA expression of immune response-associated DNA damage in mice liver induced by potassium bromate: Protective role of vanillin.

Chronic exposure to potassium bromate (KBrO3), a toxic halogen existing widely in the environment, environment through contaminated drinking water, has become a global problem of public health. The present study investigates the protective role of vanillin against KBrO3 induced oxidative stress, distruption in inflammatory cytokines expression, DNA damage, and histopathological changes. Adult mice were exposed orally to KBrO3 (2g/L of drinking water) for 2 weeks The co‐administration of vanillin to the KBrO3‐treated mice significantly prevented the plasma transaminases increase in. Furthermore, it inhibited hepatic lipid peroxidation (malondialdehyde), advanced oxidation protein product (AOPP) and protein carbonyl (PCO) formation and attenuated the KBrO3‐mediated depletion of enzymatic and non enzymatic antioxidants catalase, superoxide dismutase, and glutathione peroxidase activities and glutathione level in the liver. In addition, vanillin markedly attenuated the expression levels of proinflammatory cytokines, including tumor necrosis factor‐α, interleukin‐1β, interleukin‐6, and COX2 and prevented KBrO3‐induced hepatic cell alteration and necrosis, as indicated by histopathological data. DNA damage, as assessed by the alkaline comet assay, was also found to be low in the co‐treated group. Thus, these findings show that vanillin acts as potent chemopreventive agent against KBrO3‐mediated liver oxidative stress and genotoxicity through its antioxidant properties.

Improvement of kidney redox states contributes to the beneficial effects of dietary pomegranate peel against barium chloride-induced nephrotoxicity in adult rats

Abstract Context: Pomegranate (Punica granatum L., Punicaceae) is known to possess enormous antioxidant activity. Objective: This study investigates the protective effects of pomegranate peel against barium-mediated renal damage. Materials and methods: Rats were exposed during 21 days either to barium (67 ppm), barium + pomegranate peel (5% of diet) or to only pomegranate peel (5% of diet). Results: Exposure rats to barium provoked a significant increase in kidney malondialdehyde (MDA), advanced oxidation protein products (AOPP) and hydrogen peroxide (H2O2) levels. Creatinine, urea and uric acid levels in plasma and urine were also modified. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, non protein thiol (NPSH) and reduced glutathione (GSH) levels were decreased. Metallothionein (MT) production was increased and their genes expressions were up-regulated. All these changes were improved by dietary pomegranate peel. Moreover, the distorted histoarchitecture in kidney of barium group was alleviated by pomegranate peel. Conclusion: Our data showed, for the first time, the protective effects of pomegranate peel against barium-induced renal oxidative damage.

Effects of acrylamide graded doses on metallothioneins I and II induction and DNA fragmentation: Bochemical and histomorphological changes in the liver of adult rats

The present study investigates the toxic effects of acrylamide (ACR) administered to rats at two doses on (i) oxidative stress and disruption of pro-oxidant/antioxidant balance in hepatic cells and (ii) its correlation with metallothioneins (MTs) genes expression, DNA damage and histomorphological changes. Treated rats with 20 and 40 mg/kg body weight of ACR led to an increase in malondialdehyde, hydrogen peroxide, advanced oxidation protein products, protein carbonyl levels as well as an alteration in the antioxidant status. Total MT content in the liver and MT I and MT II genes induction were increased. Plasma transaminases activities, albumin, total protein and glucose levels were also increased, while alkaline phosphatase activity was decreased. Moreover, total cholesterol (TC), triglyceride, low-density lipoprotein cholesterol (LDL-C) levels, TC/high-density lipoprotein cholesterol (HDL-C) and LDL-C/HDL-C ratios were increased, while HDL-C decreased in a dose-dependent manner. A random DNA degradation was observed only in the liver of ACR-treated rats with the highest dose. These changes were confirmed by histopathological observations.

Potential protective effects of polysaccharide extracted from Ulva lactuca against male reprotoxicity induced by thiacloprid

Abstract Context: Polysaccharides (PSs) from seaweeds have been reported to possess biological activity of potential medicinal values. Objective: The current study was conducted to establish the protective effects of PS extracted from Ulva lactuca against oxidative stress induced by Thiacloprid (THC) in the rat reproductive system. Materials and methods: Rats were exposed either to THC, THC + PS (100 mg/kg), or THC + PS (200 mg/kg). Results: Our study showed that THC induced severe disorders in the functional sperm parameters. A decrease in antioxidant activities and their genes expression were observed in the same group, compared to the controls. Our molecular data showing also a severe DNA breakdown in the testis of THC treated group. Moreover, THC treated group showed severe histopathological changes. Conclusions: Our results revealed that PS extracted from Ulva lactuca alleviated the THC induced reprotoxicity and reduced oxidative stress damages, DNA breakdown and histological injuries in the testis.

Potassium Bromate-induced Changes in the Adult Mouse Cerebellum Are Ameliorated by Vanillin

OBJECTIVE The current study aimed to elucidate the effect of vanillin on behavioral changes, oxidative stress, and histopathological changes induced by potassium bromate (KBrO3), an environmental pollutant, in the cerebellum of adult mice. METHODS The animals were divided into four groups: group 1 served as a control, group 2 received KBrO3, group 3 received KBrO3 and vanillin, and group 4 received only vanillin. We then measured behavioral changes, oxidative stress, and molecular and histological changes in the cerebellum. RESULTS We observed significant behavioral changes in KBrO3-exposed mice. When investigating redox homeostasis in the cerebellum, we found that mice treated with KBrO3 had increased lipid peroxidation and protein oxidation in the cerebellum. These effects were accompanied by decreased Na+-K+ and Mg2+ ATPase activity and antioxidant enzyme gene expression when compared to the control group. Additionally, there was a significant increase in cytokine gene expression in KBrO3-treated mice. Microscopy revealed that KBrO3 intoxication resulted in numerous degenerative changes in the cerebellum that were substantially ameliorated by vanillin supplementation. Co-administration of vanillin blocked the biochemical and molecular anomalies induced by KBrO3. CONCLUSION Our results demonstrate that vanillin is a potential therapeutic agent for oxidative stress associated with neurodegenerative diseases.

Cytoprotective Effects of the Red Marine Alga Chondrus canaliculatus Against Maneb-Induced Hematotoxicity and Bone Oxidative Damages in Adult Rats

The current study aimed at evaluating the ability of a mineral and antioxidant-rich extract from Chondrus canaliculatus to improve maneb (MB)-induced toxicity in adult rat. The animals were divided into four groups: group 1 used as a control group, group 2 received MB, group 3 received MB + C. canaliculatus extract, and group 4 received only the algal extract. MB, a Mn-containing ethylene-bis-dithiocarbamate fungicide, induced oxidative stress damages, mineral perturbations in the plasma, urine, and bone, and genotoxicity in rats. Hematological analysis revealed in the MB-treated group a disruption in the number of red blood cells, platelets, and white blood cells associated with a striking genotoxicity. Interestingly, a significant increase in malondialdehyde and advanced oxidation protein product levels in erythrocytes and bones were found. On the other hand, an impairment of the antioxidant status in both tissues was occurred. Along, our results revealed that MB injection caused a striking drop and disruption in bone’s mineral rates, especially calcium and phosphorus. These biochemical results were in accordance with the histological and molecular changes. However, co-treatment with C. canaliculatus extract showed, for the first time, that this alga was effective against MB-induced hematotoxicity, genotoxicity, and oxidative stress in the blood and bone and maintained osteomineral metabolism and bone histo-architecture. Such observations might be explained by the strong in vitro antioxidant and antibacterial activities exhibited by the alga, as well as by its high levels in several minerals: calcium, phosphorus, sodium, potassium, magnesium, iron, and zinc.

Hypolipidemic and cardioprotective effects of Ulva lactuca ethanolic extract in hypercholesterolemic mice

Abstract Context: Hypercholesterolemia has significant cardiac consequences, since it is among the major risk factors of ischemic heart diseases. Objective: The aim was searching the cardioprotective effect of chemical constituents from the sea lettuce Ulva lactuca upon hypercholesterolemic regime in mice. Material and methods: Mice were randomly divided into three groups: untreated group, hypercholesterolemic group, and mice receiving 1% cholesterol associated with U. lactuca ethanolic extract. Results: In vitro study demonstrated that algal extract has antioxidant efficacy attributable to the presence of phenolic compounds. Additionally, the alga alleviated cardiotoxicity, as shown by the improvement of haematological parameters, white cell viability, heart oxidative stress, plasma biochemical parameters and index of atherogenesis. Gene expression of the proinflammatory cytokines TNF-α, IL-1β and IL-6 significantly decreased in the heart of U. lactuca supplemented hypercholesterolemic animals. Conclusion: It was established that the green alga, thanks to its bioactive compounds, effectively counteracts cardiotoxic effects of hypercholesterolemic regime.