Clinical outcomes and glycaemic responses to different aerobic exercise training intensities in type II diabetes: a systematic review and meta-analysis
Aims: To establish if aerobic exercise training is associated with beneficial effects on clinical outcomes and glycaemic profile in people with type II diabetes. Methods: A systematic search was conducted to identify studies through a search of MEDLINE (1985 to Sept 1, 2016, Cochrane Controlled Trials Registry (1966 to Sept 1, 2016), CINAHL, SPORTDiscus and Science Citation Index. The search strategy included a mix of MeSH and free text terms for related key concepts. Searches were limited to prospective randomized or controlled trials of aerobic exercise training in humans with type II diabetes, aged >18 years, lasting >2 weeks. Results: Our analysis included 27 studies (38 intervention groups) totalling 1372 participants, 737 exercise and 635 from control groups. The studies contain data from 39,435 patient-hours of exercise training. Our analyses showed improvements with exercise in glycosylated haemoglobin (HbA1C%) MD: -0.71%, 95% CI -1.11, -0.31; p value = 0.0005. There were significant moderator effects; for every additional week of exercise HbA1C% reduces between 0.009 and 0.04%, p = 0.002. For those exercising at vigorous intensity peak oxygen consumption (peak VO2) increased a further 0.64 and 5.98 ml/kg/min compared to those doing low or moderate intensity activity. Homeostatic model assessment of insulin resistance (HOMA-IR) was also improved with exercise MD: -1.02, 95% CI -1.77, -0.28; p value = 0.007; as was fasting serum glucose MD: -12.53 mmol/l, 95% CI -18.94, -6.23; p value <0.0001; and serum MD: -10.39 IU, 95% CI -17.25, -3.53; p value = 0.003. Conclusions: Our analysis support existing guidelines that for those who can tolerate it, exercise at higher intensity may offer superior fitness benefits and longer program duration will optimize reductions in HbA1C%.
Global proteomic profiling of the membrane compartment of bovine testis cell populations
Spermatogonial stem cells hold enormous potential in mammalian reproductive medicine through the preservation of gametes, the restoration of fertility, enhancement of germ-lineage genetic manipulation and the improvement in our understanding of stem cell biology. Here we describe the protein profiles of the membrane compartment of bovine testicular cell isolates which were enriched for germ cells using differential plating. The isolated cells were characterised with antibodies to UCHL1 (previously known as PGP9.5) for type A spermatogonia; DDX4 (previously known as VASA) for germ cells and vimentin for Sertoli cells. Ultraconservative techniques were used to specifically isolate cell membranes, with membrane protein identifications significantly increased when compared to whole cell lysates. We utilised the filter-aided sample preparation protocol for improved digestion efficiency of membrane proteins. Using ESI-LC-MS/MS, we compared the proteins present in two cell populations. A total of 1,387 proteins were identified in bovine testis cell isolates, of which 39% were membrane associated. A total of 64 proteins were differentially expressed in the non-adhered fraction (enriched for undifferentiated germ cells) compared to the adhered fraction, of which 16 were unique to this cell population and the remaining 48 showed a two-fold change (increase when compared to the adhered cell population) as judged by spectral counting. This analysis revealed a number of candidate germ cell markers including the known markers, DDX4 and UCHL1. The proteomic profiles generated in this study support and complement transcription data on gene expression and histological levels, and reinforce the potential of proteomics in identifying and characterising the protein effectors of self-renewal and/or differentiation in stem cells.