Circulating MiR-21 expression is upregulated after 30 days of head-down tilt bed rest.

Relative expression of miR-21-5p in serum was upregulated in response to 30 days of bed rest, and miRNA fold changes were positively associated with serum calcium changes. INTRODUCTION: Circulating miRNAs (c-miRNAs) have potential as biomarkers of cellular activity, and they may play a role in cell-to-cell communication. The purpose of this study was to examine c-miRNA and bone marker responses to a 30-day six-degree head-down bed rest protocol at an ambient 0.5% CO2. METHODS: Eleven participants (6 males/5 females, 25-50 years) had fasting blood draws taken 3 days before and immediately after completing the 30-day bed rest protocol at the Institute for Aerospace Medicine in Germany. Serum relative expression of miRNAs associated with bone function (miR-21-5p, -100-5p, -125b-5p, -126-3p) were analyzed using qPCR, and serum bone markers were quantitated using ELISA. RESULTS: Serum bone markers, sclerostin, and calcium significantly increased (p ≤ 0.036), and total hip aBMD significantly decreased (p = 0.003) post bed rest. Serum miR-21-5p relative expression was significantly upregulated (p = 0.018) post bed rest. Fold changes in miR-126-3p (r = 0.82, p = 0.002) and miR-21-5p (r = 0.62, p = 0.042) were positively correlated with absolute change in serum calcium. There were no sex differences in miRNA responses; women had greater percent increases in TRAP5b (37.3% vs. 16.9% p = 0.021) and greater percent decreases in total hip aBMD (- 2.15% vs. - 0.69%, p = 0.034) than men. CONCLUSION: c-miR-21-5p has potential as a biomarker of bone resorption and bone loss in an unloading condition. The upregulation of miR-21-5p may reflect an increase in osteoclast activity after bed rest, which is corroborated by the increase in TRAP5b.

A caffeine containing weight loss supplement augments hemodynamic responses after exercise.

BACKGROUND: Since the effects of supplements can be potentially harmful and/or ineffective to obtain desired positive benefits, there is a need to investigate supplementation to understand the responses of physiological systems, to educate consumers, and to provide feedback for businesses creating these supplements. The purpose of the current study was to test hemodynamic responses of a weight loss supplement and determine its effects on hemodynamic variables. METHODS: 31 participants underwent a randomized, double-blind, crossover study design and received a placebo or supplement on two separate days. Baseline measures of all variables were assessed prior to exercise. During exercise, each participant performed treadmill running at 80% VO2PEAK until volitional fatigue. Immediately post-exercise, hemodynamic measures were recorded at multiple time points. RESULTS: There was a significant condition∗time interaction with the supplement having a higher PWV for the carotid to femoral segment (p=0.004). There were also significant condition∗time interactions for heart rate (p=0.001). Large arterial elasticity was significantly lower for the supplement (p=0.005). Systolic blood pressure was conditionally higher (p=0.001), as was diastolic blood pressure (p=0.003) and mean arterial pressure (p=0.003). Vascular resistance was conditionally higher for the supplement (p=0.044). CONCLUSIONS: Ingredients in the supplement caused multiple negative effects within hemodynamics and were ineffective at increasing running time.

Disrupted in Schizophrenia 1 (DISC1) is a multicompartmentalized protein that predominantly localizes to mitochondria.

DISC1 is disrupted by a chromosomal translocation cosegregating with schizophrenia and recurrent major depression in a large Scottish family and has also been reported as a potential susceptibility locus in independent populations. We reveal a widespread and complex pattern of DISC1 expression, with at least five forms of Disrupted in Schizophrenia 1 DISC1 detectable. Mitochondria are the predominant site of DISC1 expression with additional nuclear, cytoplasmic, and actin-associated locations evident. Although the subcellular targeting of DISC1 is clearly complex, the association with mitochondria is of interest as many mitochondrial deficits have been reported in schizophrenia and other neuropsychiatric illnesses. Moreover, of the many cellular functions performed by mitochondria, their role in oxidative phosphorylation, calcium homeostasis, and apoptosis may hold particular relevance for the neuronal disturbances believed to be involved in the pathogenesis of schizophrenia.