High-fat diet and estrogen impacts the colon and its transcriptome in a sex-dependent manner.

There is a strong association between obesity and colorectal cancer (CRC), especially in men, whereas estrogen protects against both the metabolic syndrome and CRC. Colon is the first organ to respond to high-fat diet (HFD), and estrogen receptor beta (ERß) can attenuate CRC development. How estrogen impacts the colon under HFD and related sex differences has, however, not been investigated. To dissect this, mice were fed control diet or HFD for 13 weeks and administered receptor-selective estrogenic ligands for the last three weeks. We recorded impact on metabolism, colon crypt proliferation, macrophage infiltration, and the colon transcriptome. We found clear sex differences in the colon transcriptome and in the impact by HFD and estrogens, including on clock genes. ERα-selective activation reduced body weight and generated systemic effects, whereas ERß-selective activation had local effects in the colon, attenuating HFD-induced macrophage infiltration and epithelial cell proliferation. We here demonstrate how HFD and estrogens modulate the colon microenvironment in a sex- and ER-specific manner.

Eccentric exercise in ischemic cardiac patients and functional capacity: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Eccentric (ECC) exercise is an "economical" type of exercise with low energy requirements and does not cause early fatigue. Therefore, it is used for cardiac patients, who have low physical activity and exercise intolerance, as an easier kind of training. OBJECTIVE: This systematic review aimed to investigate the efficacy of ECC exercise for functional capacity (FC) in patients with ischemic heart disease. DESIGN: Systematic review. METHODS: MEDLINE via PubMed and EBSCO databases were searched for articles of randomized controlled trials of adults with ischemic heart disease who underwent ECC training as compared with other forms of exercise (concentric exercise) or no exercise and assessed FC. The methodologic quality of studies was assessed by the PEDro scale. A meta-analysis was performed with sufficient homogeneity between at least 2 studies in the pre-defined comparisons. RESULTS: Four studies, investigating a total of 99 subjects, met the inclusion criteria. The results of the studies did not clearly indicate whether ECC exercise could improve FC better than traditional forms of exercise. However, the small number of studies and their methodologic weaknesses do not allow for drawing firm conclusions. CONCLUSIONS: We found contradictory results about the effectiveness of ECC as compared with concentric exercise in terms of FC in ischemic cardiac patients. Further investigation with well-designed randomized trials is needed to determine the effectiveness of this kind of exercise for FC in such patients.

Test-retest reliability of grip strength measurement in full elbow extension to evaluate maximum grip strength.

The objective of this study was to investigate the test-retest reliability of measurement of grip strength in full elbow extension. The grip strengths of 19 healthy participants were measured using the Jamar dynamometer by the same rater on two occasions with an interval of 7 days between measures. Test-retest reliability of grip strength measurement was excellent in full elbow extension and associated with low values of standard error of measurement and small variations in the differences between the two measurements in both testing sessions.

A recombinant glycine receptor fragment forms homo-oligomers distinct from its GABA(A) counterpart.

The ligand-gated ion channel receptor superfamily includes receptors for glycine, GABA, acetylcholine and serotonin. Whereas the acetylcholine and serotonin receptors mediate excitory neurotransmissions, both glycine and GABA(A) receptors are inhibitory. In this study, a fragment of the human glycine receptor alpha1 subunit, consisting of residues Ala165-Met291 (numbering based on the precursor protein), was hyperexpressed for the first time in Escherichia coli. This fragment is highly homologous in sequence to the corresponding fragment of the GABA(A) receptor. The recombinant fragment was found to have stable beta-rich secondary structure, similar to that found for the homologous GABA(A) receptor fragment, and ordered tertiary packing, suggesting a stable structural domain. Results from laser scattering studies suggest that the fragment forms trimers in solution. In addition, SDS-induced changes in secondary structure were found to occur prior to changes in oligomerization status, suggesting that oligomerization was secondary structure dependent. A study of quaternary structure using single particle analysis electron microscopy (EM) also suggested that the fragment formed homo-trimers. One trimer measures approximately 7.5 nm in diameter with a central cavity approximately 1.5 nm across. This is the first EM study on a single domain of the glycine receptor and the result is in contrast to the pentameric assembly of the equivalent GABA(A) receptor fragment reported by us earlier. The fact that this fragment alone could form oligomers in vitro suggests that amino acid residues within this segment may be involved in the oligomerization of the glycine receptor in vivo. Furthermore, the finding that two cousin receptor fragments form distinct quaternary structures indicates that sequence similarity does not necessarily imply quaternary structure similarity and, hence, care must be taken when applying a structure model derived from studies of individual receptors to the whole ligand-gated ion channel superfamily.