Multiple doses of pegylated long‐acting growth hormone are well tolerated in healthy male volunteers and possess a potential once‐weekly treatment profile

Objectives Recombinant human growth hormone (rhGH) replacement therapy in children and adults currently requires daily subcutaneous injections for several years or lifelong. The current study examined safety, tolerability, pharmacokinetic and pharmacodynamic response parameters after single and multiple doses of a long‐acting rhGH preparation (NNC126‐0083). Design Randomized, double‐blinded, placebo‐controlled, multiple‐dose, dose‐escalating (0·02, 0·04, 0·08 and 0·16 mg protein/kg), sequential dose group trial. Subjects Forty adult Japanese healthy male volunteers (aged 20–45; body mass index: 18·0–27·0 kg/m²). Five groups (n = 8) were randomized to receive multiple doses of NNC126‐0083 (n = 6) or placebo (n = 2). Methods Primary outcome was safety, and tolerability of multiple doses of NNC126‐0083 compared with placebo. Blood samples for the assessment of pharmacokinetics (PK) and pharmacodynamics response [insulin‐like growth factor I (IGF‐I) and IGF binding protein 3 (IGFBP‐3)] were taken after multiple ascending doses. Results NNC126‐0083 was well tolerated and not associated with any local injection‐site reactions or lipoatrophy. Following administration, NNC126‐0083 levels increased rapidly and remained elevated for several days, returning to baseline before each weekly injection. Steady‐state PK was achieved after the third dosing. A more than dose‐proportional exposure was observed at the highest NNC126‐0083 dose (0·16 mg protein/kg). A strong dose‐dependent pharmacodynamic response in circulating concentrations of both IGF‐I and IGFBP‐3 compared with placebo (P < 0·0001) was observed during the administration of all doses. Conclusions Multiple administration of NNC126‐0083 in healthy male volunteers indicates that NNC126‐0083 has the potential for an efficacious, well‐tolerated, once‐weekly rhGH compound in the treatment of GH deficiency.     

Gender and the use of hormonal contraception in women are not associated with cerebral cortical 5-HT 2A receptor binding

Gender influences brain function including serotonergic neurotransmission, which may play a role in the well-known gender variations in vulnerability to mood and anxiety disorders. Even though hormonal replacement therapy in menopause is associated with globally increased cerebral 5-HT_2A receptor binding it is not clear if gender or use of hormonal contraception exhibits associations with 5-HT_2A receptor binding. We found no significant effect of gender on cortical 5-HT_2A receptor binding (P=0.15, n=132). When adjusting for the personality trait neuroticism, known to be positively correlated to frontolimbic 5-HT_2A receptor binding and to be more pronounced in women, again, the effect of gender was not significant (P=0.42, n=127). Also, the use of hormonal contraception (n=14) within the group of pre-menopausal women (total n=29) was not associated with cortical 5-HT_2A receptor binding (P=0.31). In conclusion, neither gender, nor the use of hormonal contraception in premenopausal women was associated with cortical 5-HT_2A receptor binding.     

Endocrine systems in juvenile anadromous and landlocked Atlantic salmon (Salmo salar): seasonal development and seawater acclimation

The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four days and one month seawater (SW) acclimation. Plasma GH and gill GH receptor (GHR) mRNA levels increased continuously during the spring smoltification period in the anadromous, but not in landlocked salmon. There were no differences in plasma IGF-I levels between strains, or any increase during smoltification. Gill IGF-I and IGF-I receptor (IGF-IR) mRNA levels increased in anadromous salmon during smoltification, with no changes observed in landlocked fish. Gill PRLR mRNA levels remained stable in both strains during spring. Plasma cortisol levels in anadromous salmon increased 5-fold in May and June, but not in landlocked salmon. Gill glucocorticoid receptor (GR) mRNA levels were elevated in both strains at the time of peak smoltification in anadromous salmon, while mineralocorticoid receptor (MR) mRNA levels remained stable. Only anadromous salmon showed an increase of gill 11beta-hydroxysteroid dehydrogenase type-2 (11beta-HSD2) mRNA levels in May. GH and gill GHR mRNA levels increased in both strains following four days of SW exposure in mid-May, whereas only the anadromous salmon displayed elevated plasma GH and GHR mRNA after one month in SW. Plasma IGF-I increased after four days in SW in both strains, decreasing in both strains after one month in SW. Gill IGF-I mRNA levels were only increased in landlocked salmon after 4days in SW. Gill IGF-IR mRNA levels in SW did not differ from FW levels in either strain. Gill PRLR mRNA did not change after four days of SW exposure, and decreased in both strains after one month in SW. Plasma cortisol levels did not change following SW exposure in either strain. Gill GR, 11beta-HSD2 and MR mRNA levels increased after four days in SW in both strains, whereas only the anadromous strain maintained elevated gill GR and 11beta-HSD2 mRNA levels after one month in SW. The results indicate that hormones and receptors of the GH and cortisol axes are present at significantly lower levels during spring development and SW acclimation in landlocked relative to anadromous salmon. These findings suggest that attenuation of GH and cortisol axes may, at least partially, result in reduced preparatory upregulation of key gill ion-secretory proteins, possibly a result of reduced selection pressure for marine adaptations in landlocked salmon.     

Lung vascular cell heterogeneity: endothelium, smooth muscle, and fibroblasts

The pulmonary circulation represents a unique vascular bed, receiving 100% of the cardiac output while maintaining low blood pressure. Multiple different cell types, including endothelium, smooth muscle, and fibroblasts, contribute to normal vascular function, and to the vascular response to injury. Our understanding of the basic cell biology of these various cell types, and the roles they play in vascular homeostasis and disease, remains quite limited despite several decades of study. Recent advances in approaches that enable the mapping of cell origin and the study of the molecular basis of structure and function have resulted in a rapid accumulation of new information that is essential to vascular biology. A recent National Institutes of Health workshop was held to discuss emerging concepts in lung vascular biology. The findings of this workshop are summarized in this article.     

Hypercholesterolemia in pregnant mice does not affect atherosclerosis in adult offspring

In humans, maternal hypercholesterolemia during pregnancy promotes microscopical fatty streaks in the children. The mechanism is unknown. Fatty streaks are clinically silent, and many of them regress and never develop into advanced atherosclerosis. The aim of this study was to investigate whether hypercholesterolemia in pregnant mice induced more advanced atherosclerosis in their adult progeny. Hypercholesterolemic (HC) apolipoprotein E knockout (apoE(-/-)) female mice were mated with normocholesterolemic (NC) wild-type (apoE(+/+)) males and vice versa. All parents were almost identical genetically except for apoE. Therefore, all progeny became genetically identical and heterozygous apoE(+/-). They were born of either HC (i.e. apoE(-/-)) or NC (i.e. apoE(+/+)) mothers. The progeny were killed 6 months after birth and the amount of atherosclerosis in the aortic root was assessed. Females developed more atherosclerosis than males (P<0.001) but, regardless of sex, maternal hypercholesterolemia during pregnancy had no influence on the amount of atherosclerosis in adult progeny. Males of HC mothers had lower plasma cholesterol levels than males of NC mothers. Thus, in mice, maternal hypercholesterolemia during pregnancy does not promote the development of advanced atherosclerosis in their adult progeny.     

Efficacy of and tolerance to prolonged release prazosin in patients with hypertension and non-insulin dependent diabetes

The treatment of hypertension represents one of the major elements of the cardiovascular prognosis in type II diabetes. Among antihypertensive drugs, alpha blockers may be interesting because of the absence of unfavourable effects on plasma glucose and lipid levels. OBJECTIVE: The aim of this study was to evaluate the effectiveness and the safety of prazosin osmotic tablet treatment in non-insulin-dependent diabetic patients with mild to moderate arterial hypertension. METHODS: After an initial 4-week-single-blind placebo period, 81 hypertensive subjects (162 +/- 11/96 +/- 5 mmHg) with type II diabetes were included in the study to receive prazosin osmotic tablet (o.t) open-label therapy at the dose of 2.5 mg/day for 12 weeks. After 4 weeks of treatment the dosage of prazosin o.t was increased to 5 mg/day if the diastolic blood pressure remained > or = 90 mmHg. RESULTS: Both supine and standing systolic and diastolic blood pressures were significantly decreased (P < 0.001) with prazosin therapy from 162 +/- 10/96 +/- 5 mmHg in supine and 160 +/- 12/95 +/- 6 mmHg in the upright position, to 149 +/- 15/86 +/- 9 mmHg and 148 +/- 16/86 +/- 9 mmHg respectively at the end of the 12-week-treatment period. There were no significant changes in the glycemic parameters (glycemia, haemoglobin A1c) during the prazosin therapy compared with baseline values. A significant decrease of triglycerides (P = 0.005), total cholesterol (P < 0.001) and LDL cholesterol (P = 0.03) levels was observed during prazosin therapy compared with the baseline measurements, whereas HDL cholesterol remained stable. Only 6% of the patients reported adverse events in relation with the study drug during the active treatment period. CONCLUSION: This study showed a significant decrease of the blood pressure in hypertensive subjects with type II diabetes after prazosin o.t treatment, without any change of glycemic parameters. Moreover, there was a favourable evolution of the lipidic parameters during the study characterised by a significant decrease of triglycerides and total and LDL cholesterol.