Does advancing male age influence the expression levels and localisation patterns of phospholipase C zeta (PLCζ) in human sperm?

Socio-economic factors have led to an increasing trend for couples to delay parenthood. However, advancing age exerts detrimental effects upon gametes which can have serious consequences upon embryo viability. While such effects are well documented for the oocyte, relatively little is known with regard to the sperm. One fundamental role of sperm is to activate the oocyte at fertilisation, a process initiated by phospholipase C zeta (PLCζ), a sperm-specific protein. While PLCζ deficiency can lead to oocyte activation deficiency and infertility, it is currently unknown whether the expression or function of PLCζ is compromised by advancing male age. Here, we evaluate sperm motility and the proportion of sperm expressing PLCζ in 71 males (22–54 years; 44 fertile controls and 27 infertile patients), along with total levels and localisation patterns of PLCζ within the sperm head. Three different statistical approaches were deployed with male age considered both as a categorical and a continuous factor. While progressive motility was negatively correlated with male age, all three statistical models concurred that no PLCζ–related parameter was associated with male age, suggesting that advancing male age is unlikely to cause problems in terms of the sperm’s fundamental ability to activate an oocyt

Canagliflozin and Renal Outcomes in Type 2 Diabetes and Nephropathy

BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to 300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m 2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

A Validated Age-Related Normative Model for Male Total Testosterone Shows Increasing Variance but No Decline after Age 40 Years

The diagnosis of hypogonadism in human males includes identification of low serum testosterone levels, and hence there is an underlying assumption that normal ranges of testosterone for the healthy population are known for all ages. However, to our knowledge, no such reference model exists in the literature, and hence the availability of an applicable biochemical reference range would be helpful for the clinical assessment of hypogonadal men. In this study, using model selection and validation analysis of data identified and extracted from thirteen studies, we derive and validate a normative model of total testosterone across the lifespan in healthy men. We show that total testosterone peaks [mean (2.5-97.5 percentile)] at 15.4 (7.2-31.1) nmol/L at an average age of 19 years, and falls in the average case [mean (2.5-97.5 percentile)] to 13.0 (6.6-25.3) nmol/L by age 40 years, but we find no evidence for a further fall in mean total testosterone with increasing age through to old age. However we do show that there is an increased variation in total testosterone levels with advancing age after age 40 years. This model provides the age related reference ranges needed to support research and clinical decision making in males who have symptoms that may be due to hypogonadism.Publisher PDFPeer reviewe

Cardiovascular safety and efficacy of the PCSK9 inhibitor evolocumab in patients with and without diabetes and the effect of evolocumab on glycaemia and risk of new-onset diabetes: a prespecified analysis of the FOURIER randomised controlled trial.

BACKGROUND: The proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor evolocumab reduced LDL cholesterol and cardiovascular events in the FOURIER trial. In this prespecified analysis of FOURIER, we investigated the efficacy and safety of evolocumab by diabetes status and the effect of evolocumab on glycaemia and risk of developing diabetes. METHODS: FOURIER was a randomised trial of evolocumab (140 mg every 2 weeks or 420 mg once per month) versus placebo in 27 564 patients with atherosclerotic disease who were on statin therapy, followed up for a median of 2·2 years. In this prespecified analysis, we investigated the effect of evolocumab on cardiovascular events by diabetes status at baseline, defined on the basis of patient history, clinical events committee review of medical records, or baseline HbA1c of 6·5% (48 mmol/mol) or greater or fasting plasma glucose (FPG) of 7·0 mmol/L or greater. The primary endpoint was a composite of cardiovascular death, myocardial infarction, stroke, hospital admission for unstable angina, or coronary revascularisation. The key secondary endpoint was a composite of cardiovascular death, myocardial infarction, or stroke. We also assessed the effect of evolocumab on glycaemia, and on the risk of new-onset diabetes among patients without diabetes at baseline. HbA1c was measured at baseline then every 24 weeks and FPG was measured at baseline, week 12, week 24, and every 24 weeks thereafter, and potential cases of new-onset diabetes were adjudicated centrally. In a post-hoc analysis, we also investigated the effects on glycaemia and diabetes risk in patients with prediabetes (HbA1c 5·7-6·4% [39-46 mmol/mol] or FPG 5·6-6·9 mmol/L) at baseline. FOURIER is registered with ClinicalTrials.gov, number NCT01764633. FINDINGS: At study baseline, 11 031 patients (40%) had diabetes and 16 533 (60%) did not have diabetes (of whom 10 344 had prediabetes and 6189 had normoglycaemia). Evolocumab significantly reduced cardiovascular outcomes consistently in patients with and without diabetes at baseline. For the primary composite endpoint, the hazard ratios (HRs) were 0·83 (95% CI 0·75-0·93; p=0·0008) for patients with diabetes and 0·87 (0·79-0·96; p=0·0052) for patients without diabetes (pinteraction=0·60). For the key secondary endpoint, the HRs were 0·82 (0·72-0·93; p=0·0021) for those with diabetes and 0·78 (0·69-0·89; p=0·0002) for those without diabetes (pinteraction=0·65). Evolocumab did not increase the risk of new-onset diabetes in patients without diabetes at baseline (HR 1·05, 0·94-1·17), including in those with prediabetes (HR 1·00, 0·89-1·13). Levels of HbA1c and FPG were similar between the evolocumab and placebo groups over time in patients with diabetes, prediabetes, or normoglycaemia. Among patients with diabetes at baseline, the proportions of patients with adverse events were 78·5% (4327 of 5513 patients) in the evolocumab group and 78·3% (4307 of 5502 patients) in the placebo group; among patients without diabetes at baseline, the proportions with adverse events were 76·8% (6337 of 8256 patients) in the evolocumab group and 76·8% (6337 of 8254 patients) in the placebo group. INTERPRETATION: PCSK9 inhibition with evolocumab significantly reduced cardiovascular risk in patients with and without diabetes. Evolocumab did not increase the risk of new-onset diabetes, nor did it worsen glycaemia. These data suggest evolocumab use in patients with atherosclerotic disease is efficacious and safe in patients with and without diabetes. FUNDING: Amgen