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2.
Primates ; 64(1): 91-103, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36436178

RESUMO

In South Africa, chacma baboons (Papio hamadryas ursinus) living near peri-urban areas may forage on anthropogenic food. Baboons have been recorded to damage crops, scatter waste from trash bins, and damage homes. A number of methods have been tested over the past 20 years to solve these problems, but none proved successful over the long-term or involved considerable costs. An efficient management system requires a detailed knowledge of how baboon troops proceed and organize during these urban foraging actions. This study examines the response of a troop of baboons to an experimental reduction of anthropogenic food sources in a peri-urban environment, the George campus of Nelson Mandela University (SA). We gradually suppressed access to waste food in trash cans, reducing the amount of anthropogenic food available. This change in food availability led baboons to modify their urban foraging strategy. They compensated for the lack of anthropogenic food by spending more time foraging on natural food and less time in urban areas. However, the troop still exploited waste-free areas during the experiment and even more when the conditions were normal again. Overall, these results show the ability of baboons to adapt to changes in anthropogenic food availability but also that they are highly dependent on this type of resource. Limiting its access is a mitigation strategy that humans must absolutely develop for reaching a high level of coexistence with baboons.


Assuntos
Papio hamadryas , Papio ursinus , Humanos , Animais , Papio ursinus/fisiologia , Papio , Alimentos , África do Sul
3.
Food Funct ; 5(4): 663-70, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24569685

RESUMO

Various epidemiological studies have shown that a regular and moderate consumption of red wine is correlated with a decreased relative risk of developing coronary heart disease and cancer. These health benefits are commonly attributed to high contents of polyphenols, particularly resveratrol, representing important sources of antioxidants. However, resveratrol does not seem to be the only bioactive compound present in the wine which contains numerous other polyphenols. The present study investigates the efficiency of red wine extracts (RWEs), containing different polyphenols, on colon cancer cell proliferation in vitro and on colonic aberrant crypt foci (ACF) in vivo. Proliferation, cell cycle analysis and incidence of ACF were monitored to examine the effects of RWEs. RWEs derived from a long vinification process exhibit superior anti-proliferative activity in colon cancer cells and prevent the appearance of ACF in mice. Interestingly, quercetin and resveratrol, representing two major bio-active polyphenols, exhibit synergistic anti-proliferative effects. These data suggest that the efficacy of RWEs on colon carcinogenesis may depend on the polyphenolic content, synergistic interaction of bio-active polyphenols and modulation of cellular uptake of polyphenols.


Assuntos
Neoplasias do Colo/prevenção & controle , Polifenóis/metabolismo , Substâncias Protetoras/metabolismo , Vinho/análise , Animais , Carcinogênese , Proliferação de Células/efeitos dos fármacos , Colo/patologia , Colo/fisiopatologia , Neoplasias do Colo/dietoterapia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/fisiopatologia , Humanos , Masculino , Camundongos
4.
Mol Nutr Food Res ; 56(2): 345-51, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22419533

RESUMO

While the cardioprotective effect of moderate and regular wine consumption in primary prevention has been well documented, the goal of the present investigation was to explore the effect of wine intake on blood parameters (lipid, anti-oxidant capacity, and erythrocyte membrane potential and fluidity) in post myocardial infarct patients to evaluate perspectives in secondary prevention. A clinical intervention trial has been undertaken on a group of selected post myocardial infarct patients who gave written informed consent for participation in this study prior to enrolment. This two-week study has been conducted on hospitalized patients during a cardiac readaptation period. During this period, patients were submitted to a "Western prudent" diet (inspired by the Mediterranean diet) and two groups have been compared on a drawn basis: patients receiving red wine (250 mL daily) to patients receiving water. Physical, clinical, and blood parameters were evaluated on Days 1 and 14. The data show a positive effect of low wine consumption on blood parameters (decrease in total cholesterol and LDL; increase in erythrocyte membrane fluidity and antioxidant status). The results show that a moderate consumption of red wine even for a short period associated with a "Western prudent" diet improves various blood parameters in lipid and anti-oxidative status in patients with previous coronary ischemic accidents.


Assuntos
Membrana Eritrocítica/efeitos dos fármacos , Infarto do Miocárdio/sangue , Infarto do Miocárdio/dietoterapia , Vinho , Antioxidantes/metabolismo , Colesterol/sangue , Citocinas/sangue , Dieta , Feminino , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Fluidez de Membrana/efeitos dos fármacos , Pessoa de Meia-Idade , Infarto do Miocárdio/reabilitação , Albumina Sérica/metabolismo , Triglicerídeos/sangue
5.
Genes Nutr ; 6(2): 161-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21541654

RESUMO

Resveratrol is a natural dietary polyphenol found in grape skin, red wine, and various other food products. Resveratrol has proved to be an effective chemopreventive agent for different malignant tumors. It has also been shown to prevent vascular alterations such as atherosclerosis and inflammatory-associated events. In view of these observations, we investigated the anti-proliferative and pro-apoptotic activities of resveratrol on a tumoral cardiac cell line (HL-1 NB) derived from mouse tumoral atrial cardiac myocytes. These effects were compared with those found on normal neonatal mouse cardiomyocytes. HL-1 NB cells and neonatal cardiomyocytes were treated with resveratrol (5, 30, and/or 100 µM) for different times of culture (24, 48, and/or 72 h). Resveratrol effects were determined by various microscopical and flow cytometric methods. After resveratrol treatment, a strong inhibition of tumoral cardiac HL1-NB cell growth associated with a loss of cell adhesion was observed. This cell proliferation arrest was associated with an apoptotic process revealed by an increased percentage of cells with fragmented and/or condensed nuclei (characteristic of apoptotic cells) identified after staining with Hoechst 33342 and by the presence of cells in subG1. At the opposite, on normal cardiomyocytes, no cytotoxic effects of resveratrol were observed, and a protective effect of resveratrol against norepinephrine-induced apoptosis was found on normal cardiomyocytes. Altogether, the present data demonstrate that resveratrol (1) induces apoptosis of tumoral cardiac HL1-NB cells, (2) does not induce cell death on normal cardiomyocytes, and (3) prevents norepinephrine-induced apoptosis on normal cardiomyocytes.

6.
Ann N Y Acad Sci ; 1215: 48-59, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21261641

RESUMO

Numerous studies have reported interesting properties of trans-resveratrol, a phytoalexin, as a preventive agent of several important pathologies: vascular diseases, cancers, viral infections, and neurodegenerative processes. These beneficial effects of resveratrol have been supported by observations at the cellular and molecular levels in both cellular and in vivo models, but the cellular fate of resveratrol remains unclear. We suggest here that resveratrol uptake, metabolism, and stability of the parent molecule could influence the biological effects of resveratrol. It appears that resveratrol stability involves redox reactions and biotransformation that influence its antioxidant properties. Resveratrol's pharmacokinetics and metabolism represent other important issues, notably, the putative effects of its metabolites on pathology models. For example, some metabolites, mainly sulfate-conjugated resveratrol, show biological effects in cellular models. The modifications of resveratrol stability, chemical structure, and metabolism could change its cellular and molecular targets and could be crucial for improving or decreasing its chemopreventive properties.


Assuntos
Antioxidantes/metabolismo , Membrana Celular/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Estilbenos/metabolismo , Animais , Transporte Biológico Ativo/fisiologia , Humanos , Resveratrol
7.
Org Biomol Chem ; 9(3): 701-10, 2011 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-21079866

RESUMO

The biological properties and possible pharmacological applications of benzo[kl]xanthene lignans, rare among natural products and synthetic compounds, are almost unexplored. In the present contribution, the possible interaction of six synthetic benzo[kl]xanthene lignans and the natural metabolite rufescidride with DNA has been investigated through a combined STD-NMR and molecular docking approach, paralleled by in vitro biological assays on their antiproliferative activity towards two different cancer cell lines: SW 480 and HepG2. Our data suggest that the benzo[kl]xanthene lignans are suitable lead compounds for the design of DNA selective ligands with potential antitumour properties.


Assuntos
Antinematódeos/química , DNA/química , Lignanas/química , Conformação de Ácido Nucleico , Xantenos/química , Antinematódeos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Lignanas/farmacologia , Modelos Moleculares , Relação Estrutura-Atividade , Xantenos/farmacologia
8.
Eur J Med Chem ; 45(7): 2972-80, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20395019

RESUMO

Resveratrol is the subject of intense research because of the abundance of this compound in the human diet and as one of the most valuable natural chemopreventive agents. Further advances require new resveratrol analogs be used to identify the structural determinants of resveratrol for the inhibition potency of cell proliferation by comparing experimental and docking studies. Therefore, we synthesized new trans/(E)- and cis/(Z)-resveratrol - analogs not reported to date - by modifying the hydroxylation pattern of resveratrol and a double bond geometry. We included them in a larger panel of 14 molecules, including (Z)-3,5,4'-trimethoxystilbene, the most powerful molecule that is used as reference. Using a docking model complementary to experimental studies on the proliferation inhibition of the human colorectal tumor SW480 cell line, we show that methylation is the determinant substitution in inhibition efficacy, but only in molecules bearing a Z configuration. Most of the synthetic methylated derivatives (E or Z) stop mitosis at the M phase and lead to polyploid cells, while (E)-resveratrol inhibits cells at the S phase. Docking studies show that almost all of the docked structures of (Z)-polymethoxy isomers, but not most of the (E)-polymethoxy isomers substantially overlap the docked structure of combretastatin A-4, taken as reference ligand at the colchicine-tubulin binding site.


Assuntos
Estilbenos/química , Estilbenos/farmacologia , Sítios de Ligação , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colchicina/metabolismo , DNA/metabolismo , Humanos , Hidróxidos/química , Modelos Moleculares , Resveratrol , Estereoisomerismo , Estilbenos/síntese química , Estilbenos/metabolismo , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
9.
J Gerontol A Biol Sci Med Sci ; 63(10): 1027-33, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18948552

RESUMO

In mammals, during the aging process, an atrophy of the muscle fibers, an increase in body fat mass, and a decrease in skeletal muscle oxidative capacities occur. Compounds and activities that interact with lipid oxidative metabolism may be useful in limiting damages that occur in aging muscle. In this study, we evaluated the effect of L-carnitine and physical exercise on several parameters related to muscle physiology. We described that supplementing old rats with L-carnitine at 30 mg/kg body weight for 12 weeks (a) allowed the restoration of L-carnitine level in muscle cells, (b) restored muscle oxidative activity in the soleus, and (c) induced positive changes in body composition: a decrease in abdominal fat mass and an increase in muscle capabilities without any change in food intake. Moderate physical exercise was also effective in (a) limiting fat mass gain and (b) inducing an increase in the capacities of the soleus to oxidize fatty acids.


Assuntos
Envelhecimento/efeitos dos fármacos , Envelhecimento/fisiologia , Carnitina/farmacologia , Mitocôndrias/metabolismo , Músculo Esquelético/fisiologia , Condicionamento Físico Animal , Animais , Masculino , Músculo Esquelético/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Estatísticas não Paramétricas
10.
Meat Sci ; 78(3): 331-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22062286

RESUMO

Human adults store around 20g of l-carnitine. In the human body, l-carnitine is not metabolized but excreted through the kidney. Lost l-carnitine has to be replenished either by a biosynthetic mechanism or by the consumption of foods containing l-carnitine. Today, there is no "official" recommended daily allowance for l-carnitine but the daily need for l-carnitine intake has been estimated in the wide range of 2-12µmol/day/kg body weight for an adult human. In this study we evaluated the effect of freezing and of different cooking methods on the l-carnitine content of red meat and fish. l-carnitine was abundantly present in all beef products analyzed. The amounts in the various cuts were similar and our data showed that freezing or cooking did not modify l-carnitine content. Salmon contained about 12 times less l-carnitine than beef but except in smoked salmon, cooking or freezing did not alter l-carnitine content. This study confirms the important role that meet products play for providing adequate amount of l-carnitine to the human body.

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