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Tauopathies are a class of neurodegenerative diseases associated with the pathological aggregation of tau protein in the human brain. Although numerous studies in mouse models of Alzheimer disease (AD) have shown a correlation among diet, beta-amyloid and AD onset, little is known about the impact of diet on Tau. We investigated whether a low fat-protein diet (LFPD) may improve lifespan, cognitive and locomotor activity in P301L-tg mouse model of tauopathy. Our data indicate that LFPD has a beneficial effect on these parameters. Tg mice fed with standard diet shown a decrease in body weight, food intake and survival rate if compared to wild type animals. In contrast, LFPD counteracted weight loss, increased mortality and ameliorated cognitive and locomotor performances in tg mice. LFPD also reduced the abnormal accumulation of agglomerates of P-Tau (pathological features of tauopathies) and the expression of apoptotic markers (i.e., TUNEL immunopositive neurons) in the prefrontal cerebral cortex and hippocampus of P301L-tg mice. Interestingly, some of these effects are sex-dependent. For instance, tg females, but not males, fed with LFPD had a significant increase of body weight and a reduction of P-Tau agglomerates compared to tg fed with standard diet. These changes correlated with a more pronounced improvement of cognition and locomotor activity in females than in male tg fed with LFPD. Altogether, these results suggest a sex dependent neuroprotective effect of LFPD in P301L-tg mice, suggesting that lifestyle intervention strategies may be clinically relevant for delaying the onset of cognitive impairment and dementia, especially in females.

Investigation of bodies recovered in water comprises an important proportion of medico-legal cases, but is affected by relevant limits concerning the specific decomposition processes and the cause of death. Few indications are provided by literature concerning the post mortem modification of corpses in water, but for a general variability in decomposition degree, and only few experimental projects have been performed in order to verify the influence of water on the decomposition process. On the other hand, in order to reconstruct the cause of death, at present, the diatom test is considered as the "golden standard" for the diagnosis of drowning, although recent literature has pointed out its relative reliability and the frequent problems of contamination. This pilot study was performed to observe the changes of animal remains in aquatic environments. The following experimental system was set up: three piglet corpses, who died by natural causes independent from the study, were immerged in water rich in diatoms (Navicola, Order Pennales) in a tank exposed to the open air; macroscopic, histochemical and diatoms analysis were performed after 1, 2 and 3 months. Decomposition effects were fast: since the first month the skin appeared colliquated with exposure of the underlying bone surface, whereas at the second and third month the inner viscera were no longer recognizable; histology revealed that the skin was well preserved at 1 month, but morphology was completely altered at the second month, whereas at the third month epidermis was no longer visible. Diatom testing showed the presence of contamination both in the first and second piglet; the finding of a sea-diatom, on the other hand, was completely unexpected. This study performed for the first time histochemical testing on animal models submerged in water: although the results became negative after the second month, some microscopic structure could still be recognized at the end of the experimental project; on the other hand, the search for diatoms in the samples proved the high possibility of post mortem contamination.

We investigated the in vivo effects of dietary conjugated linoleic acid (CLA) on subcutaneous adipose tissue from heavy pigs to clarify the involvement of possibly different causative effects in the established antiadipogenic effect of CLA. Pigs [n = 36; initial body weight, 106 kg live weight (LW)] were assigned to 1 of 2 LW-matched groups supplemented with either 0 or 0.75% of a CLA preparation containing 50% CLA isomers. The pigs were slaughtered at 155 kg LW and adipose tissue analyzed. CLA supplementation affected ash content, and decreased iodine values (P < 0.01) and adipocyte size (P < 0.05). The fat content of adipose tissue was lower (P < 0.05) in females than castrated males, and females had smaller (P < 0.01) adipocytes than castrated males. Neither CLA nor sex influenced adipocyte lipid droplet diameter or the extent of lipid peroxidation as determined by quantitation of Schiff's histochemical reaction. NADPH-diaphorase was not influenced by CLA treatment. Preadipocyte proliferation rates were lower in pigs fed CLA (P < 0.05), whereas the number of adipocyte apoptotic nuclei was greater (P < 0.05). Preadipocyte proliferation was also greater (P < 0.05) in females than castrated males. Neuronal and endothelial nitric oxide synthase activities did not differ between groups in adipose tissue vessels, but inducible nitric oxide synthase expression in adipocytes was lower in pigs fed CLA (P = 0.05). These findings suggest that the antiadipogenic effect of CLA in heavy pigs is not a direct effect but may occur by downregulation of a NO-mediated lipolytic pathway.