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The redox co-factor nicotinamide adenine dinucleotide (NAD) declines with age, and NAD deficits are specifically associated with dysfunctional energy metabolism in late-onset Alzheimer's disease (LOAD). Nicotinamide riboside (NR), a dietary NAD precursor, has been suggested to ameliorate the aging process or neurodegeneration. We assessed whether NR with or without caffeine, which increases nicotinamide mononucleotide transferase subtype 2 (NMNAT2), an essential enzyme in NAD production, modulates bioenergetic functions in LOAD. In LOAD patients-and young or old control individuals-derived dermal fibroblasts as well as in induced pluripotent stem cell-differentiated neural progenitors and astrocytes, NR and caffeine cell type-specifically increased the NAD pool, transiently enhanced mitochondrial respiration or glycolysis and altered the expression of genes in the NAD synthesis or consumption pathways. However, continued treatment led to reversed bioenergetic effects. Importantly, NR and caffeine did not alter the characteristics of a previously documented inherent LOAD-associated bioenergetic phenotype. Thus, although NR and caffeine can partially restore diminished NAD availability, increasing NAD alone may not be sufficient to boost or restore energy metabolism in brain aging or alter aberrant energy management in LOAD. Nicotinamide riboside might still be of value in combination with other agents in preventive or therapeutic intervention strategies to address the aging process or age-associated dementia.

This comprehensive review summarizes the evidence regarding use of cerebral autoregulation-directed therapy at the bedside and provides an evaluation of its impact on optimizing cerebral perfusion and associated functional outcomes. Multiple studies in adults and several in children have shown the feasibility of individualizing mean arterial blood pressure and cerebral perfusion pressure goals by using cerebral autoregulation monitoring to calculate optimal levels. Nine of these studies examined the association between cerebral perfusion pressure or mean arterial blood pressure being above or below their optimal levels and functional outcomes. Six of these nine studies (66%) showed that patients for whom median cerebral perfusion pressure or mean arterial blood pressure differed significantly from the optimum, defined by cerebral autoregulation monitoring, were more likely to have an unfavorable outcome. The evidence indicates that monitoring of continuous cerebral autoregulation at the bedside is feasible and has the potential to be used to direct blood pressure management in acutely ill patients.

The purpose of this study was to determine whether there was a significant difference in static stretching (SS), dynamic stretching (DS), and no stretching (NS) on maximal strength (one-repetition maximum [1RM]) in the bench and leg presses using free weights on 19 college-aged men and 32 women. Most of the participants were moderately to very active and had previous experience with weight training. The design was repeated measures, with each treatment being randomly assigned. Each testing session was separated by 72 hours. Moderate-intensity stretching was defined as stretching as far as possible without any assistance, and subjects were encouraged to do their best. For the SS routine, the chest, shoulder, triceps, quadriceps, and hamstrings were stretched. Three repetitions were performed for 15 seconds, each separated by a 10-second rest. For DS, the upper-body stretch was swinging each arm, one at a time, as far forward and then as far backward as possible in a diagonal plane. For the legs, the same movement was done for each leg, except performed in a sagittal plane. Each forward and backward movement took about 2 seconds. Three 30-second sets were administered, and a 10-second rest was allowed between sets. Next, 1RM was determined for the bench and leg presses in random order. Two warm-up sets were given, followed by several 1RM attempts. The last successful lift was recorded as the 1RM. Data were reported using means +/- SD. A one-way ANOVA with repeated measures was used with alpha set at 0.05. There was no significant difference among the treatments. Moderate-intensity stretching does not seem to adversely affect 1RM in the bench and leg presses.