The futile creatine cycle and the synthesis of fatty acids in inguinal white adipose tissue from growing rats, submitted to a hypoprotein-hyperglycidic diet for 15 days.

The low-protein, high-carbohydrate (LPHC) diet administered to growing rats soon after weaning, for 15 days, promoted an increase in energy expenditure by uncoupling protein 1 (UCP1) in interscapular brown adipose tissue, and also due to the occurrence of the browning process in the perirenal white adipose tissue (periWAT). However, we believe that inguinal white adipose tissue (ingWAT) may also contribute to energy expenditure through other mechanisms. Therefore, the aim of this work is to investigate the presence of the futile creatine cycle, and the origin of lipids in ingWAT, since that tissue showed an increase in the lipids content in rats submitted to the LPHC diet for 15 days. We observed increases in creatine kinase and alkaline phosphatase activity in ingWAT, of the LPHC animals. The mitochondrial Nicotinamide adenine dinucleotide reduced/nicotinamide adenine dinucleotide oxidized ratio is lower in ingWAT of LPHC animals. In the LPHC animals treated with ß-guanidinopropionic acid, the extracellular uptake of creatine in ingWAT was lower, as was the rectal temperature. Regarding lipid metabolism, we observed that in ingWAT, lipolysis in vitro when stimulated with noradrenaline is lower, and there were no changes in baseline levels. In addition, increases in the activity of enzymes were also observed: malic, glucose-6-phosphate dehydrogenase, and ATP-citrate lyase, in addition to an increase in the PPARγ content. The results show the occurrence of the futile creatine cycle in ingWAT, and that the increase in the relative mass may be due to an increase in de novo fatty acid synthesis.

Effects of topical ketorolac tromethamine on tear parameters, meibography, goblet cell density, and conjunctival oxidative stress in healthy dogs.

OBJECTIVES: The objective of the study was to evaluate whether a twice-daily instillation of 0.45% preservative-free ketorolac tromethamine (FKT) or 0.4% benzalkonium chloride-preserved ketorolac tromethamine (BACKT), every 12 h for 30 days may affect tear film parameters and the meibography in healthy dogs. Additionally, we assessed whether the same treatments irritated the ocular surface, affected goblet cell density (GCD), and the levels of oxidative stress biomarkers (OSB) in the conjunctiva of the same dogs. PROCEDURES: Experimental and masked comparison study. In 11 healthy dogs baseline values of the lipid layer thickness, tear meniscus height, non-invasive tear breakup time (NI-TFBT), and the meibomian gland (MG) loss were assessed by OSAvet®. For each dog, one eye received 40 µL of BACKT, while the other received 40 µL FKT, every 12 h for 30 consecutive days. Tear parameters and meibography were repeated 15, 30, and 60 days post-treatments. Conjunctival hyperemia and blepharospasm were monitored at the same time points. At baseline and Day 30, a conjunctival biopsy was collected for GCD and OSB determination. RESULTS: Conjunctival hyperemia and blepharospasm were not observed. At Day 15, the MG loss increased only in FKT-treated eyes (p < .001). On Day 30, both treatment groups showed increased MG loss, shortened NI-TFBT, and reduced GCD and catalase (p < .05). At Day 30, BACKT-treated eyes showed lower levels of superoxide dismutase (SOD) (p = .006) and higher levels of malondialdehyde (MDA) (p = .02). Differences between treatments were not observed for any parameter at any time point (p > .05). 60 days after treatment, OSAvet® parameters tended to return to values assessed at baseline; however, significant differences remained for MG loss (p < .05). CONCLUSIONS: Twice-daily instillation of KT, containing or not BAC, for 30 consecutive days shortened NI-TFBT, decreased GCD, and increased the MG loss in healthy dogs. KT should be used with caution when prescribed for long periods, particularly in patients with tear film abnormalities. However, future controlled studies using KT, BAC, and other topical NSAIDs are indicated to further support this finding.

Acute supplementation of growing rats with Brazil nut flour increases hepatic lipid content but prevents oxidative damage in the liver.

Brazil nuts (BN) (Bertholletia excels, Bonpl.), are of great importance because of their nutritional properties and economic value. They can be consumed in natura or as flour (BNF). In this study, we evaluated the effects of BNF and BN intakes (Both 5% and 15%) on metabolic parameters of rats for 15 days. Serum Selenium (Se) levels were higher in BN-15% and BNF-15% groups. Lipid content was reduced in retroperitoneal and epididymal adipose tissues in all groups and in the BN-5% group in the liver. However, liver lipids increased in the BNF-15% group. The levels of carbonylated proteins and lipid peroxidation in the liver were not altered. The data reveal that the increase in hepatic lipids in the BNF-15% group probably occurred due to the high concentration of free fatty acids present in the flour. The Se bioavailability in the diet contributed to the preservation of the liver function in rats. PRACTICAL IMPLICATIONS: The consumption of BN is common in the population. However, changes in eating habits have led to a more frequent consumption of vegetable derivatives, such as drinks and oils. The cake residue generated after processing is still considered of high nutritional value, since it is a source of protein and minerals such as Se. Because of its low cost, the use of pie at the industrial level is becoming increasingly more interesting for the development of new products, and the Brazil nut flour (BNF) is considered a good option. Our study showed that just like BN, BNF can be a source of selenium for the body, although changes in lipid metabolism and physiological parameters can be observed depending on the amount used. We believe that the results of this investigation can be used to guide the development of new technologies and products containing BN.