Nutritional epidemiology shows that insufficient protein intake is related to senile dementia. The levels of protein intake in aged people are positively associated with memory function, and elderly people with high protein intake have a low risk of mild cognitive impairment. Although the beneficial roles of protein nutrition in maintaining brain function in aged people are well demonstrated, little is known about the mechanism by which dietary intake of protein affects memory and brain conditions. We fed aged mice a low protein diet (LPD) for 2 months, which caused behavioral abnormalities, and examined the nutritional effect of essential amino acid administration under LPD conditions. The passive avoidance test revealed that LPD mice demonstrated learning and memory impairment. Similarly, the LPD mice showed agitation and hyperactive behavior in the elevated plus maze test. Moreover, LPD mice exhibited decreased concentrations of gamma-aminobutyric acid (GABA), glutamate, glycine, dopamine, norepinephrine, serotonin and aspartate in the brain. Interestingly, oral administration of seven essential amino acids (EAAs; valine, leucine, isoleucine, lysine, phenylalanine, histidine, and tryptophan) to LPD mice, which can be a source of neurotransmitters, reversed those behavioral changes. The oral administration of EAAs restored the brain concentration of glutamate, which is involved in learning and memory ability and may be associated with the observed behavioral changes. Although the details of the link between decreased amino acid and neurotransmitter concentrations and behavioral abnormalities must be examined in future studies, these findings suggest the importance of dietary protein and essential amino acids for maintaining brain function.

Intake of specific seven essential amino acids affects the pathology of the brain.

Cilnidipine is an L/N-type calcium channel blocker (CCB). The effects of cilnidipine on N-type channels give it unique organ-protective properties via the suppression of hyperactivity in the sympathetic nervous system (SNS) and renin-angiotensin-aldosterone system (RAAS). In the present study, we compared the effects of cilnidipine and amlodipine (an L-type CCB) on cardiac and renal functions in spontaneously-hypertensive rats injected with adriamycin (ADR). After the weekly administration of ADR for 3 weeks, spontaneously-hypertensive rats were orally administered cilnidipine (20 mg/kg per day), amlodipine (3 mg/kg per day), or vehicle once daily for 4 weeks. A control group received saline rather than ADR, followed by vehicle for 4 weeks. Cilnidipine and amlodipine produced similar reductions in blood pressure after 4 weeks. Cilnidipine ameliorated ADR-induced heart and kidney damage, whereas amlodipine slightly improved cardiac echocardiographic parameters, but did not protect against ADR-induced renal damage. Cilnidipine (but not amlodipine) suppressed the reflex SNS and RAAS hyperactivity caused by their antihypertensive effects. Furthermore, cilnidipine and amlodipine treatment decreased the urinary levels of adrenocortical hormones. The protective effects of cilnidipine against ADR-induced renal and cardiac dysfunction might be associated with its blockade of N-type calcium channels, in addition to its pleiotropic actions, which include the inhibition of the RAAS.

BackgroundThe effect of peer-led training in basic life support (BLS) in the education of medical students has not been assessed.Subjects and methodsThis study was a randomized controlled trial with a blinded outcome assessor. A total of 74 fourth-year medical students at Ehime University School of Medicine, Japan were randomly assigned to BLS training conducted by either a senior medical student (peer-led group) or a health professional (professional-led group). The primary outcome measure was the percentage of chest compressions with adequate depth (38–51 mm) by means of a training mannequin evaluated 20 weeks after BLS training. Secondary outcome measures were compression depth, compression rate, proportion of participants who could ensure adequate compression depth (38–51 mm) and adequate compression rate (90–110/minute), and retention of BLS knowledge as assessed by 22-point questionnaire.ResultsPercentage chest compressions with adequate depth (mean ± SD) was 54.5% ± 31.8% in the peer-led group and 52.4% ± 35.6% in the professional-led group. The 95% confidence interval (CI) of difference of the means was −18.7% to 22.8%. The proportion of participants who could ensure an adequate mean compression rate was 17/23 (73.9%) in the peer-led group but only 8/22 (36.4%) in the professional-led group (P = 0.011). On the 22-point questionnaire administered 20 weeks after training, the peer-led group scored 17.2 ± 2.3 whereas the professional-led group scored 17.8 ± 2.0. The 95% CI of difference of the means was −1.72 to 0.57.ConclusionPeer-led training in BLS by medical students is feasible and as effective as health professional-led training.

No abstract