Intermittent fasting attenuates lipopolysaccharide-induced neuroinflammation and memory impairment.

BACKGROUND: Systemic bacterial infections often result in enduring cognitive impairment and are a risk factor for dementia. There are currently no effective treatments for infection-induced cognitive impairment. Previous studies have shown that intermittent fasting (IF) can increase the resistance of neurons to injury and disease by stimulating adaptive cellular stress responses. However, the impact of IF on the cognitive sequelae of systemic and brain inflammation is unknown. METHODS: Rats on IF for 30 days received 1 mg/kg of lipopolysaccharide (LPS) or saline intravenously. Half of the rats were subjected to behavioral tests and the other half were euthanized two hours after LPS administration and the hippocampus was dissected and frozen for analyses. RESULTS: Here, we report that IF ameliorates cognitive deficits in a rat model of sepsis by a mechanism involving NF-κB activation, suppression of the expression of pro-inflammatory cytokines, and enhancement of neurotrophic support. Treatment of rats with LPS resulted in deficits in cognitive performance in the Barnes maze and inhibitory avoidance tests, without changing locomotor activity, that were ameliorated in rats that had been maintained on the IF diet. IF also resulted in reduced levels of mRNAs encoding the LPS receptor TLR4 and inducible nitric oxide synthase (iNOS) in the hippocampus. Moreover, IF prevented LPS-induced elevation of IL-1α, IL-1ß and TNF-α levels, and prevented the LPS-induced reduction of BDNF levels in the hippocampus. IF also significantly attenuated LPS-induced elevations of serum IL-1ß, IFN-γ, RANTES, TNF-α and IL-6 levels. CONCLUSIONS: Taken together, our results suggest that IF induces adaptive responses in the brain and periphery that can suppress inflammation and preserve cognitive function in an animal model of systemic bacterial infection.

Influence of anabolic steroid treatment associated to physical exercise in the ultrasonic vocalization of rats.

Unlike humans, who communicate in frequency bands between 250 Hz and 6 kHz, rats can communicate in frequencies above 18 kHz. Their vocalization types depend on the context and are normally associated to subjective or emotional states. It was reported significant vocal changes due to administration of replacement testosterone in a trained tenor singer with hypogonadism. Speech-Language Pathology clinical practices are being sought by singers who sporadically use anabolic steroids associated with physical exercise. They report difficulties in reaching and keeping high notes, "breakage" in the passage of musical notes and post singing vocal fatigue. Those abnormalities could be raised by the association of anabolic steroids and physical exercise. Thus, in order to verify if this association could promote vocal changes, maximum, minimum and fundamental frequencies and call duration in rats treated with anabolic steroids and physically trained (10 weeks duration) were evaluated. The vocalizations were obtained by handling the animals. At the end of that period, rats treated and trained showed significant decrease in call duration, but not in other parameters. The decrease in call duration could be associated to functional alterations in the vocal folds of treated and trained animals due to a synergism between anabolic steroids and physical training.

Behavioral and enzymatic bioassays with Serjania erecta Radlk., Sapindaceae, correlated with cognitive dysfunctions / Comportamento e ensaios bioenzimáticos com Serjania erecta Radlk., sapindaceae, correlacionados com disfunções cognitivas

The purpose of this study was to investigate the crude extract of Serjania erecta Radlk., Sapindaceae, and its bioactive agents as preventive or inhibitor of memory loss in rodents, as well as other factors correlated with Alzheimer's syndrome: antioxidant and anticholinesterase activity, mainly as plant adaptogen - low toxicity and regulation action. The blocking cholinergic reversion activity (scopolamine) in the test of the passive avoidance was detected by measuring latency in young and adult animals. It presented low toxicity, with protective effect as shown by biochemical analysis (hypoglycemic/hypotriglyceridemic). Elevated levels (above 83 percent) of antioxidant activity were detected. AchE and BuChE inhibition were also detected in the chromatographic fractions, which were active both orally and directly on CNS (ICV).

O objetivo deste estudo foi pesquisar o extrato bruto de Serjania erecta Radlk., Sapindaceae, e seus bioativos como preventivos ou inibidores de perda de memória em roedores, e outros fatores correlacionados com a síndrome de Alzheimer: atividade antioxidante e anticolinesterásicas, principalmente como planta adaptógena, baixa toxicidade e ação regulatória. A reversão do bloqueador colinérgico (escopolamina) no teste da esquiva passiva foi detectada pela latência mensurada em animais jovens e adultos. Apresentou baixa toxicidade, com efeito protetor na análise bioquímica (hipoglicemia/hipotrigliceridemia). Índices elevados (acima 83 por cento) na atividade antioxidante foram observados. A inibição da AChE e BuChE foi perceptível nas frações cromatográficas, confirmando as ações via oral e diretamente no SNC.