Influence of physical activity on addiction parameters of rats exposed to amphetamine which were previously supplemented with hydrogenated vegetable fat.

Amphetamine (AMPH) and its derivatives are addictive drugs used to promote and enhance alertness, motivation, willingness, courage and wellbeing. However, their chronic use is related to memory loss, emotional instability, insomnia, psychosis and paranoia. In the last decades, modern society has included processed foods, rich in trans fatty acids (TFA), in their diet, what has been related to several health problems including increased AMPH preference and self-administration. In this scenario, physical activity appears to be useful to attenuate rewarding symptoms related to addictive drugs mainly by affecting brain neuroplasticity and neurotransmission. The current study has been developed to assess the influence of physical activity on addiction parameters of rats exposed to AMPH which were previously supplemented with hydrogenated vegetable fat (HVF), rich in TFA. After six weeks of HVF or soybean oil (SO, control group) supplementation, adult rats were conditioned with d,l-AMPH or vehicle for 14 days. Then, half of each experimental group was submitted to physical activity in treadmill running sessions (60min/day, 5 days/week) for 5 weeks. Animals were re-conditioned with AMPH or vehicle for 3 more days, to observe drug relapse. Locomotor activity and anxiety-like symptoms were observed 24h after the last AMPH reconditioning, and fatty acids composition was quantified in the ventral tegmental area, striatum and prefrontal cortex. All animals showed AMPH preference, but only SO sedentary showed drug relapse. No differences were observed in locomotor activity among groups, while HVF-supplemented group showed decreased exploration per se, and physical activity prevented this. Moreover, AMPH-HVF group showed increased anxiety-like symptoms, which were prevented by physical activity. These results indicate that HVF supplementation modifies AMPH addiction, whereas regular physical activity could be protective against both AMPH and TFA damages.

Role of the adjunctive antimicrobial photodynamic therapy to periodontal treatment at plasmatic oxidative stress and vascular behavior.

BACKGROUND: To evaluate for the first time in vivo the effects of methylene blue (MB) photosensitizer dissolved in ethanol in antimicrobial photodynamic therapy (aPDT) as adjuvant periodontal treatment, at plasmatic oxidative stress and vascular behavior in rat model. METHODS: Wistar rats were divided into negative control (NC, no periodontitis) and positive control (PC, with periodontitis, without any treatment). The other groups had periodontitis and were treated with scaling and root planing (SRP); SRP+aPDT+MB dissolved in water (aPDT I); SRP+aPDT+MB dissolved in ethanol (aPDT II). The periodontitis was induced by ligature at the mandibular right first molar. At 7/15/30days, rats were euthanized, the plasma was used to determine oxidative stress parameters and gingival tissue for histomorphometric analysis. RESULTS: PC showed higher thiobarbituric acid reactive substances levels in 7/15/30days. aPDT II was able to block the lipid peroxidation, especially between 15th and 30th days. Glutathione reduced levels were consumed in PC, aPDT I and II groups throughout the experiment. aPDT II increased the vitamin C levels which were restored in this group in the 30th day. aPDT II group showed the highest number of blood vessels. CONCLUSION: In summary, the aPDT with MB dissolved in ethanol provides better therapeutic responses in periodontitis treatment.

Chronic consumption of trans fat can facilitate the development of hyperactive behavior in rats.

In recent decades, the increased consumption of processed foods, which are rich in hydrogenated vegetable fat (HVF), has led to a decreased consumption of fish and oilseed, rich in omega-3 fatty acids. This eating habit provides an increased intake of trans fatty acids (TFA), which may be related to neuropsychiatric conditions, including inattention and hyperactivity. In this study, we evaluated the potential connection between prolonged trans fat consumption and development of hyperactivity-like symptoms in rats using different behavioral paradigms. Trans fat intake for 10 months (Experiment 1), as well as during pregnancy and lactation across two sequential generations of rats, (Experiment 4) induced active coping in the forced swimming task (FST). In addition, HVF supplementation was associated with increased locomotion before and after amphetamine (AMPH) administration (Experiment 2). Similarly, HVF supplementation during pregnancy and lactation were associated with increased locomotion in both young and adult rats (Experiment 3). Furthermore, trans fat intake across two sequential generations increased locomotor and exploratory activities following stressors (Experiment 4). From these results, we suggest that chronic consumption of trans fat is able to enhance impulsiveness and reactivity to novelty, facilitating hyperactive behaviors.

Cross-generational trans fat intake exacerbates UV radiation-induced damage in rat skin.

We evaluated the influence of dietary fats on ultraviolet radiation (UVR)-induced oxidative damage in skin of rats. Animals from two consecutive generations born of dams supplemented with fats during pregnancy and breastfeeding were maintained in the same supplementation: soybean-oil (SO, rich in n-6 FA, control group), fish-oil (FO, rich in n-3 FA) or hydrogenated-vegetable-fat (HVF, rich in TFA). At 90 days of age, half the animals from the 2nd generation were exposed to UVR (0.25 J/cm(2)) 3×/week for 12 weeks. The FO group presented higher incorporation of n-3 FA in dorsal skin, while the HVF group incorporated TFA. Biochemical changes per se were observed in skin of the HVF group: greater generation of reactive oxygen species (ROS), lower mitochondrial integrity and increased Na(+)K(+)-ATPase activity. UVR exposure increased skin wrinkles scores and ROS generation and decreased mitochondrial integrity and reduced-glutathione levels in the HVF group. In FO, UVR exposure was associated with smaller skin thickness and reduced levels of protein-carbonyl, together with increased catalase activity and preserved Na(+)K(+)-ATPase function. In conclusion, while FO may be protective, trans fat may be harmful to skin health by making it more vulnerable to UVR injury and thus more prone to develop photoaging and skin cancer.