A strategy to improve rodent control while reducing rodenticide release into the environment.

In addition to having a negative impact on the health of people and domestic animals, rodents often cause enormous damage to the environment by disrupting natural biodiversity. The negative impacts of rodents in urban and rural areas have required intensive use of rodentcides in spite of the proven risk of secondary poisoning of non-target predators and scavengers. Continuous and intensive use of rodenticides has led to environmental pollution through their retention in the environment. Commensal rodents are predominantly managed with anticoagulant rodenticides, which are very persistent in the environment and move up the food chain and accumulate in the bodies of predators and scavengers. Generally, the use of anticoagulant rodenticides continues, and there is a need to take appropriate measures to reduce their harmful impact. The efficacy of second generation anticoagulants (bromadiolone, difenacoum and brodifacoum), combined either mutually or with chlorophacinone at reduced doses (0.001 % and 0.0008 %), in controlling brown rats (Rattus norvegicus) was tested in a four-day no-choice feeding test. Combinations of second generation anticoagulants were more effective than the combination of chlorophacinone and second generation anticoagulants. The results indicate that combinations of different anticoagulants at multifold lower doses than the standard may provide a successful tool for brown rat control and a more environment-friendly method of rodent control and protection of non-target animals.

Glycosaminoglycan dermatan sulfate supplementation decreases diet-induced obesity and metabolic dysfunction in mice.

Glycosaminoglycans are complex carbohydrates used as nutraceuticals for diverse applications. We studied the potential of the glycosaminoglycan dermatan sulfate (DS) to counteract the development of diet-induced obesity (DIO) using obesity-prone mice fed a high-fat diet (HFD) as a model. Oral DS supplementation protected the animals against HFD-induced increases in whole-body adiposity, visceral fat mass, adipocyte size, blood glucose levels, insulin resistance, and pro-inflammatory lipids levels in brown adipose tissue (BAT) and the liver, where it largely counteracted the HFD-induced changes in the nonpolar metabolome. Protection against DIO in the DS-supplemented mice occurred despite higher energy intake and appeared to be associated with increased energy expenditure, higher uncoupling protein 1 expression in BAT, decreased BAT "whitening," and an enhanced channeling of fuel substrates toward skeletal muscle. This work is the first preclinical study to examine the anti-obesity activity of DS tested individually in vivo. The results support possible uses of DS as an active component in functional foods/supplements to manage obesity and associated metabolic diseases.

Accumulation of metal trace elements in different body parts of terrestrial Roman snail Helix pomatia L., 1758 on three polluted sites in Serbia.

Atmospheric pollution remains one of the growing concerns in the twenty-first century, with particular focus on metal trace elements (MTE) from anthropogenic sources, due to their adverse effects on biota. The concentration and type of MTE in the atmosphere and in the soil are diverse, depending on the origin of pollutants, which can cause diverse detrimental effects on organisms living in the nearby environment. Three sites in Central Serbia with different origins of MTE pollution (urban contamination, smelting, and fly ash area) were assessed, using terrestrial Roman snails (Helix pomatia) as biomarker organisms. These snails are sentinel organisms and are known for their capacities for accumulation of MTE. Snails were sampled and their body was divided in three parts: viscera, foot, and shell and concentrations of MTE were determined in each of these body parts using inductively coupled plasma optical spectrometry. Results showed contrasting MTE accumulation patterns in body parts of the snails. Of three studied sites, snails sampled in the vicinity of fly ash containment had lower concentrations of MTE compared to other two polluted sites.

Relationships between the Pathogen Erysiphe alphitoides, the Phytophagous Mite Schizotetranychus garmani (Acari: Tetranychidae) and the Predatory Mite Euseius finlandicus (Acari: Phytoseiidae) in Oak.

Food webs on forest trees include plant pathogens, arthropods, and their natural enemies. To increase the understanding of the impact of a plant pathogen on herbivore-natural enemy interactions, we studied the powdery mildew fungus Erysiphe alphitoides, the phytophagous mite Schizotetranychus garmani, and the predatory and mycophagous mite Euseius finlandicus in pedunculate oak (Quercus robur) leaves. In June, July and August of 2016, we assessed the severity of powdery mildew, mite population density and adult female mite size in 30 trees in three forests near Belgrade, Serbia. In August, the infection severity of E. alphitoides related positively to the population density of S. garmani and negatively to the body size of S. garmani females. Throughout the vegetative season, the infection severity of E. alphitoides related positively to the population density of E. finlandicus but not to its body size. The effect of E. alphitoides on the population density and adult size of S. garmani was not mediated by the population density of E. finlandicus, and vice versa. Interactions were consistent in all forests and varied with the summer month. Our findings indicate that E. alphitoides can influence the average body size and population densities of prey and predatory mites studied, irrespective of predator-prey relationships.

Protective Effects of Individual and Combined Low Dose Beta-Carotene and Metformin Treatments against High-Fat Diet-Induced Responses in Mice.

Anti-obesity activity has been reported for beta-carotene (BC) supplementation at high doses and metformin (MET). We studied whether BC treatment at a closer to dietary dose and MET treatment at a lower than therapeutic dose are effective in ameliorating unwanted effects of an obesogenic diet and whether their combination is advantageous. Obesity-prone mice were challenged with a high-fat diet (HFD, 45% energy as fat) for 4 weeks while receiving a placebo or being treated orally with BC (3 mg/kg/day), MET (100 mg/kg/day), or their combination (BC+MET); a fifth group received a placebo and was kept on a normal-fat diet (10% energy as fat). HFD-induced increases in body weight gain and inguinal white adipose tissue (WAT) adipocyte size were attenuated maximally or selectively in the BC+MET group, in which a redistribution towards smaller adipocytes was noted. Cumulative energy intake was unaffected, yet results suggested increased systemic energy expenditure and brown adipose tissue activation in the treated groups. Unwanted effects of HFD on glucose control and insulin sensitivity were attenuated in the treated groups, especially BC and BC+MET, in which hepatic lipid content was also decreased. Transcriptional analyses suggested effects on skeletal muscle and WAT metabolism could contribute to better responses to the HFD, especially in the MET and BC+MET groups. The results support the benefits of the BC+MET cotreatment.

Mouse Models to Study Antiobesogenic Effects of Carotenoids.

Carotenoids entail a vast potential to tackle health problems including obesity and some of its comorbidities. The use of animal models remains necessary, particularly at early stages of research (preclinical) and for advancing in mechanistic aspects of carotenoid action. No single animal model completely mimics human absorption and metabolism of carotenoids, and the best model must be chosen considering the specific application, characteristics of the individual models, and funding and facilities available. Here, we propose three protocols in mice to investigate the potential of a given carotenoid, carotenoid mixture, or carotenoid-rich extract to (a) counteract the development of obesity and prevent the metabolic alterations caused by feeding mice a moderate high-fat diet; (b) improve the metabolic profile of obese animals with metabolic alterations caused by chronic high-fat diet feeding; and (c) act as coadjuvants in weight loss strategies (reversion to a low fat diet) applied to diet-induced obese animals.

A Lipophilic Fucoxanthin-Rich Phaeodactylum tricornutum Extract Ameliorates Effects of Diet-Induced Obesity in C57BL/6J Mice.

Phaeodactylum tricornutum (P. tricornutum) comprise several lipophilic constituents with proposed anti-obesity and anti-diabetic properties. We investigated the effect of an ethanolic P. tricornutum extract (PTE) on energy metabolism in obesity-prone mice fed a high fat diet (HFD). Six- to eight-week-old male C57BL/6J mice were switched to HFD and, at the same time, received orally placebo or PTE (100 mg or 300 mg/kg body weight/day). Body weight, body composition, and food intake were monitored. After 26 days, blood and tissue samples were collected for biochemical, morphological, and gene expression analyses. PTE-supplemented mice accumulated fucoxanthin metabolites in adipose tissues and attained lower body weight gain, body fat content, weight of white adipose tissue (WAT) depots, and inguinal WAT adipocyte size than controls, independent of decreased food intake. PTE supplementation was associated with lower expression of Mest (a marker of fat tissue expandability) in WAT depots, lower gene expression related to lipid uptake and turnover in visceral WAT, increased expression of genes key to fatty acid oxidation and thermogenesis (Cpt1, Ucp1) in subcutaneous WAT, and signs of thermogenic activation including enhanced UCP1 protein in interscapular brown adipose tissue. In conclusion, these data show the potential of PTE to ameliorate HFD-induced obesity in vivo.