Grape Seed Extract Reduces the Degree of Atherosclerosis in Ligature-Induced Periodontitis in Rats - An Experimental Study.

The associations between periodontitis and cardiovascular diseases have been intensely studied in recent years. Oxidative stress is involved in the initiation and both progression of periodontitis and atherosclerosis. Antioxidants can reduce the effects of oxidative stress on inflammatory diseases. Our aim was to measure the effects of a grape seed extract (GSE), rich in antioxidants, on atherosclerosis caused by ligature-induced periodontitis in rats. Thirty male Wistar rats were randomly divided into three groups of 10: control group, periodontitis group, and periodontitis group treated with GSE (GSE group). Periodontitis was induced by placing an orthodontic wire around the cervix of the first mandibular molar and keeping it in place for 4 weeks. On days 1, 7 and 28, blood samples were taken to assess oxidative stress and inflammation markers (malondialdehyde and glutathione - MDA, reduced glutathione - GSH, C reactive protein) and lipids. After 4 weeks, the animals were euthanized, and aortas were collected for histopathologic examination. MDA was significantly higher in Periodontitis group compared to the other groups only at day 7. GSH was significantly increased in the Control and GSE groups on days 1 and 7, compared to Periodontitis group and on day 28 higher in GSE vs. Periodontitis groups. C reactive protein was significantly increased in the Periodontitis group on days 1 and 7 compared to both groups. Cholesterol was significantly decreased in the aortas of GSE group at day 28 compared to the Periodontitis group. Oral administration of a grape seed extract reduces the oxidative stress, inflammation and atherosclerosis in a rat model of ligature-induced periodontitis.

Cutaneous wound healing using polymeric surgical dressings based on chitosan, sodium hyaluronate and resveratrol. A preclinical experimental study.

Wound healing is a complex and dynamic process that involves modifying the wound environment depending on the patient's health status. Scar formation depends on many factors that influence wound healing, are important to bear in mind because most of the negative factors involved can be stopped by implementing an adequate treatment. The consensus in wound therapy recommends dressings that should keep a moist and alkaline environment thus creating a protective barrier against mechanical stress and secondary infections, in view of promoting granulation. In the current paper, we aimed to synthesize a polymer-based sponge containing chitosan-sodium hyaluronate-resveratrol (CHR) and to evaluate its regenerative potential. The process of synthesizing the CHR polymer was described before microtomography analysis was conducted and the density and porosity of the obtained sponges was assessed. The cytotoxicity was evaluated in vitro. By undertaking the in vivo testing of the CHR polymer, we aimed to determine the CHR sponge's potential to stimulate tissue regeneration after inflicting a controlled, reproducible and measurable skin wound in an animal model. Skin punch biopsies were harvested from the healed area and were subjected to histopathological evaluation. The results obtained in this study confirmed that this polymer accelerates the formation of granulation facilitating wound healing, while also achieving a bacteriostatic outcome.

Influence of Genista tinctoria L. or methylparaben on subchronic toxicity of bisphenol A in rats.

OBJECTIVE: To evaluate the influence of an extract of Genista tinctoria L. herba (GT) or methylparaben (MP) on histopathological changes and 2 biomarkers of oxidative stress in rats subchronicly exposed to bisphenol A (BPA). METHODS: Adult female Wistar rats were orally exposed for 90 d to BPA (50 mg/kg), BPA+GT (35 mg isoflavones/kg) or BPA+MP (250 mg/kg). Plasma and tissue samples were taken from liver, kidney, thyroid, uterus, ovary, and mammary gland after 30, 60, and 90 d of exposure respectively. Lipid peroxidation and in vivo hydroxyl radical production were evaluated by histological analysis along with malondialdehyde and 2,3-dihydroxybenzoic acid detection. RESULTS: The severity of histopathological changes in liver and kidneys was lower after GT treatment than after BPA or BPA+MP treatment. A minimal thyroid receptor antagonist effect was only observed after BPA+MP treatment. The abnormal folliculogenesis increased in a time-dependent manner, and the number of corpus luteum decreased. No significant histological alterations were found in the uterus. The mammary gland displayed specific estrogen stimulation changes at all periods. Both MP and GT revealed antioxidant properties reducing lipid peroxidation and BPA-induced hydroxyl radical generation. CONCLUSION: GT L. extract ameliorates the toxic effects of BPA and is proved to have antioxidant potential and antitoxic effect. MP has antioxidant properties, but has either no effect or exacerbates the BPA-induced histopathological changes.

Inhibition of UVB-induced skin phototoxicity by a grape seed extract as modulator of nitrosative stress, ERK/NF-kB signaling pathway and apoptosis, in SKH-1 mice.

Molecular mechanisms concerning the modulation of nitrosative stress, signal transduction and proliferation/apoptosis by a grape seed extract, Burgund Mare variety (BM), in SKH-1 mice exposed to UVB, were investigated. The animals were irradiated with single and multiple doses of UVB in 10 consecutive days. In each experiment were used five groups of animals: control, vehicle, UVB irradiated, vehicle+UVB, BM+UVB. The extract was applied topically, 30 min before each UVB exposure, in a dose of 4 mg total polyphenols/cm(2). BM remarkably inhibited UVB-induced activation of inducible nitric oxide synthase (iNOS) and therefore generation of nitric oxide (NO) and nitrotyrosine, in a UVB single dose regimen. BM also suppressed NF-kB activation by UVB but did not affect the activity of total ERK 1/2. In multiple UVB irradiations, BM increased NO formation and total ERK 1/2 activity and reduced iNOS activity and nitrotyrosine levels, inhibited cell proliferation, diminished p53 and caspase-3 immunoreactivities and increased the percentage of Bcl-2 positive cells. We concluded that BM modulates the apoptotic response of SKH-1 mice skin in UVB irradiation by the inhibition of p53, caspase-3, Bax/Bcl-2 and proliferating cell nuclear antigen expressions, as well as by reducing the activation of iNOS and NF-kB.

Effects of astaxanthin supplementation on chemically induced tumorigenesis in Wistar rats.

BACKGROUND: Astaxanthin (ASTA) is a fat-soluble xanthophyll with powerful antioxidant functions. It is extracted from e.g. salmon, an important food source for certain human populations known to have a reduced risk of tumor development. It is possible that ASTA plays a role in cancer chemoprevention in such populations. The purpose of this study was to investigate the effects of dietary ASTA on chemically induced mammary tumorigenesis using N-methyl-N-nitroso-urea (MNU) in immature Wistar rats. METHODS: Thirty-six 37 days old juvenile female Wistar rats were at random allocated to 4 groups of which Groups 1 and 2 received a single dose of 55 mg MNU/kg body weight. The effects of ASTA was evaluated by giving rats of Groups 2 and 4 a dose of 50 mg ASTA/kg/day for the entire duration of the study. Group 3 rats received feed added alimentary oil.Necropsy and histopathological examinations were carried out on each rat 14 months after the administration of MNU. Haematological values and antioxidative status were determined. Oxidative stress was evaluated by monitoring superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in hepatic tissue. Lipid peroxidation and carbonylation of proteins was determined in protein extracts from the liver. RESULTS: Tumor development occurred only in rats of Groups 1 and 2, i.e. MNU exposed animals. Frequency of tumor development in general and average number of tumors per animal were insignificant between these two groups. Mammary gland tumors developed in equal frequencies in Group 1 and 2 rats, respectively. Although only rather few tumors were found in the mammary glands, a substantial number of other tumors were found in Group 1 and 2 rats, but at equal rates.Biochemical analyses showed significant higher levels of GPx, malondialdehyde and dinitrophenylhydrazine in Group 1 rats that for rats in all other groups thus indicating protective effects of ASTA on MNU induced hepatic oxidative stress. CONCLUSIONS: Supplementation with ASTA did not reduce tumorigenesis induced by MNU in Wistar rats. However, supplementation with ASTA seemed to have anti-inflammatory effects.

The effects of grape seeds polyphenols on SKH-1 mice skin irradiated with multiple doses of UV-B.

The study investigated the protective activity of red grape seeds (Vitis vinifera L, Burgund Mare variety) (BM) extracts in vivo on multiple doses of ultraviolet radiation (UV)-B-induced deleterious effects in SKH-1 mice skin. Eighty 8-weeks-old female SKH-1 mice were divided into 8 groups: control, vehicle, UV-B irradiated, vehicle+UV-B irradiated, BM 2.5mg polyphenols (PF)/cm(2)+UV-B irradiated, BM 4 mg PF/cm(2)+UV-B irradiated, UV-B+BM 2.5mg PF/cm(2), UV-B+BM 4 mg PF/cm(2). The extract was applied topically before or after each UV-B exposure (240 mJ/cm(2)), for 10 days consecutively. The antioxidant activity of BM extract is higher than gallic acid (k(BM)=0.017, k(gallic acid)=0.013). Multiple doses of UV-B generated the formation of cyclobutane pyrimidine dimers (CPDs) and sunburn cells, increased glutathione peroxidase (GPx) and catalase (CAT) activities respectively glutathione (GSH) and IL-1ß levels in skin. In group treated with 2.5mg PF/cm(2) before UV-B irradiation BM extract inhibited UV-B-induced sunburn cells, restored the superoxide dismutase (MnSOD) activity, increased insignificantly CAT and GPx activities and reduced IL-1ß level. The BM 4.0 mg PF/cm(2) treatment decreased GSH level and reduced the percentage of CPDs positive cells in skin. Both doses of BM extract administered after UV-B irradiation increased the MnSOD and GPx activities and reduced the formation of sunburn cells in skin. Our results suggest that BM extract might be a potential chemo-preventive candidate in reducing the oxidative stress and apoptosis induced by multiple doses of UV-B in skin.