Luteal phase support for assisted reproductive technologies: between past, present and future.

The luteal phase is defined as the period between ovulation and either the establishment of a pregnancy or the onset of menses two weeks later. Assisted reproductive technologies (ART), and in particular controlled ovarian stimulation (COS), negatively interfere with the endocrine mechanisms normally regulating the luteal phase. Up to now, there is no generally accepted opinion as to the most appropriate therapeutic schemes for luteal phase support in ART cycles. Progesterone-based protocols are the most frequently adopted, while alternative regimens including human chorionic gonadotropin (hCG) and GnRH agonists (GnRH-a) are controversial. A GnRH-a can be used instead of hCG for ovulation triggering and the effectiveness of luteal phase support in such new protocols is the object of a growing number of experimental studies. Currently, vaginal progesterone is considered as the first line therapy for luteal phase support (LPS). The starting-time and the duration of luteal phase supplementation after the onset of pregnancy are still debated. Despite the lack of clinical or biological evidence supporting the efficacy of luteal phase support in intrauterine insemination cycles, the use of progesterone has become a well-established practice.

Methylenetetrahydrofolate reductase gene promoter hypermethylation in semen samples of infertile couples correlates with recurrent spontaneous abortion.

STUDY QUESTION: Is the methylation status of the methylenetetrahydrofolate reductase (MTHFR) promoter region in semen samples associated with 'recurrent spontaneous abortion' (RSA)? SUMMARY ANSWER: MTHFR promoter hypermethylation is more frequent in semen samples from RSA couples than in semen samples from infertile couples with no history of RSA (NRSA) and affects the whole sperm population significantly more often. WHAT IS KNOWN ALREADY: Modifications to the MTHFR gene such as polymorphisms and promoter methylations are associated with male infertility. STUDY DESIGN, SIZE AND DURATION: Retrospective cohort study of semen samples from 20 RSA couples, 147 NRSA couples and 20 fertile men between 2011 and 2012. MATERIALS, SETTING AND METHODS: DNA from the semen samples of RSA, NRSA and fertile men were analyzed by methylation-specific PCR amplification using primers which anneal to the methylated or unmethylated cytosine-phosphodiester bond guanine (CpG) islands within the promoter region of MTHFR. The specificity of the PCR products was assessed by DNA sequencing. MAIN RESULTS AND THE ROLE OF CHANCE: The methylated MTHFR epigenotype (including samples where it co-existed with unmethylated MTHFR epigenotypes) was detected in 75% of RSA men, 54% of NRSA men and 15% of fertile men. MTHFR methylation was observed in the whole sperm population in semen samples from 55% of RSA men compared with 8% in NRSA men (P < 0.05) and 0% in fertile men (P < 0.05). DNA sequencing analysis was fully concordant with the PCR results and revealed that when MTHFR methylation occurred, CpG islands within the promoter region were 100% methylated (hypermethylation of MTHFR promoter). LIMITATIONS, REASONS FOR CAUTION: The relatively small sample size of RSA infertile couples. WIDER IMPLICATIONS OF THE FINDINGS: The hypermethylation of the MTHFR gene promoter should be taken into consideration as a novel putative risk factor in RSA etiology. STUDY FUNDING/COMPETING INTEREST(S): Our institution has received an FAR research grant from the University of Ferrara, Ferrara, Italy. No competing interests declared.

Noneosinophilic asthma in children: relation with airway remodelling.

Noneosinophilic asthma is increasingly recognised as an important clinical-pathological phenotype in adults. However, this entity has scarcely been investigated in children. In particular, it is unknown whether airway remodelling would develop in children with non-eosinophilic asthma to the same degree as in children with eosinophilic disease. We analysed bronchial biopsies from 80 children undergoing bronchoscopy for appropriate clinical indications: 21 with noneosinophilic asthma, 34 with eosinophilic asthma and 25 control children. Features of airway remodelling - basement membrane thickening, epithelial loss and angiogenesis - and immune activation - inflammatory infiltrate, interleukin (IL)-4, IL-5, transforming growth factor (TGF)-ß, TGF-ß receptor type II - were quantified by histology and immunohistochemistry. The main components of airway remodelling were present in children with noneosinophilic asthma just as in those with eosinophilic disease. Indeed, compared with control children, both noneosinophilic and eosinophilic asthmatic children had thickened basement membrane, increased epithelial loss and higher number of vessels. Moreover, in both groups of asthmatics, expression of IL-4 and IL-5 was increased, while that of TGF-ß receptor type II was reduced, compared with controls. This study demonstrates that structural changes typical of asthma develop in asthmatic children even in the absence of a prominent eosinophilic infiltrate, indicating that other mechanisms, besides eosinophilic inflammation, may promote airway remodelling early in life.

Increased activation of p38 MAPK in COPD.

Inflammation, oxidative stress and apoptosis, which are involved in chronic obstructive pulmonary disease (COPD) pathogenesis, may activate the p38 subgroup of mitogen-activated protein kinases (MAPKs). Therefore, the aim of the present study was to evaluate the expression of the phosphorylated, active form of p38 MAPK (phospho-p38) in the lungs of COPD patients. Surgical specimens were obtained from 18 smokers with COPD at different stages of disease severity, plus nine smoking and eight nonsmoking subjects with normal lung function. Phospho-p38+ cells were quantified by immunohistochemistry in both alveolar spaces and alveolar walls. Moreover, a Western blot analysis of phospho-p38 and total p38alpha isoform expressed by alveolar macrophages was performed. Phospho-p38+ alveolar macrophages and phospho-p38+ cells in alveolar walls were increased in patients with severe and mild/moderate COPD, compared with smoking and nonsmoking controls. Moreover, they were inversely correlated to values of forced expiratory volume in one second (FEV(1)) and FEV(1)/forced vital capacity. Western blot analysis showed that phosphorylated p38, but not the total p38alpha isoform, was specifically increased in alveolar macrophages from COPD patients. Activation of the p38 mitogen-activated protein kinase pathway appears to be involved in the pathogenesis of chronic obstructive pulmonary disease. The present findings suggest that this protein may be a suitable pharmacological target for therapeutic intervention.

Transforming growth factor-beta type II receptor in pulmonary arteries of patients with very severe COPD.

A mild-to-moderate increase in pulmonary arterial pressure is often associated with severe chronic obstructive pulmonary disease (COPD). Transforming growth factor (TGF)-beta is a cytokine involved in the maintenance of integrity of vasculature. The aim of the study was to investigate whether the TGF-beta pathway might be involved in the development of pulmonary hypertension associated with COPD. Surgical specimens from 14 patients undergoing lung transplantation for very severe COPD (forced expiratory volume in one second 17 +/- 2% of the predicted value) and from seven donors were examined. The expression of TGF-beta1 and TGF-beta type II receptor (TGF-betaRII), cell proliferation index and structural changes in pulmonary arteries were quantified immunohistochemically. In severe COPD patients, increased expression of TGF-betaRII was observed in both the tunica media and intima, which was associated with a normal proliferation index in both layers. Conversely, significant thickening of the tunica intima, which was not present in the tunica media, was observed, suggesting that mechanisms other than cell proliferation may be involved in intimal thickening. In conclusion, in the pulmonary arteries of patients with severe chronic obstructive pulmonary disease, there is upregulation of transforming growth factor-beta type II receptor expression associated with a normal proliferation index. These findings suggest the activation of an antiproliferative pathway, which might explain the relatively low degree of pulmonary hypertension observed in these subjects.

Decreased expression of TGF-beta type II receptor in bronchial glands of smokers with COPD.

BACKGROUND: The role of transforming growth factor-beta1 (TGF-beta1) in chronic obstructive pulmonary disease is still controversial, but it has been proposed that it may protect from mucus hypersecretion since it is able to downregulate mucin production. A study was undertaken to investigate the expression of TGF-beta1 and its type II receptor (TGF-beta RII) in the bronchial glands of smokers with COPD. METHODS: The expression of TGF-beta(1) and TGF-beta RII were examined immunohistochemically in the bronchial glands of 24 smokers undergoing lung resection for solitary peripheral nodules: 12 with airflow limitation (smokers with COPD) and 12 with normal lung function. RESULTS: The expression of TGF-beta1 in bronchial glands was similar in the two groups of subjects while that of TGF-beta RII was lower in smokers with COPD than in smokers with normal lung function (p=0.004). TGF-beta RII expression was inversely correlated with the values of Reid's index, a measure of gland size (p=0.02, r=-0.50). CONCLUSIONS: In the bronchial glands of smokers with COPD there is decreased expression of TGF-beta RII which is associated with bronchial gland enlargement. These findings support the view that the absence of TGF-beta signalling may induce structural changes in the bronchial glands which, in turn, may promote mucus hypersecretion.

Neutrophilic infiltration within the airway smooth muscle in patients with COPD.

BACKGROUND: COPD is an inflammatory disorder characterised by chronic airflow limitation, but the extent to which airway inflammation is related to functional abnormalities is still uncertain. The interaction between inflammatory cells and airway smooth muscle may have a crucial role. METHODS: To investigate the microlocalisation of inflammatory cells within the airway smooth muscle in COPD, surgical specimens obtained from 26 subjects undergoing thoracotomy (eight smokers with COPD, 10 smokers with normal lung function, and eight non-smoking controls) were examined. Immunohistochemical analysis was used to quantify the number of neutrophils, macrophages, mast cells, CD4+ and CD8+ cells localised within the smooth muscle of peripheral airways. RESULTS: Smokers with COPD had an increased number of neutrophils and CD8+ cells in the airway smooth muscle compared with non-smokers. Smokers with normal lung function also had a neutrophilic infiltration in the airway smooth muscle, but to a lesser extent. When all the subjects were analysed as one group, neutrophilic infiltration was inversely related to forced expiratory volume in 1 second (% predicted). CONCLUSIONS: Microlocalisation of neutrophils and CD8+ cells in the airway smooth muscle in smokers with COPD suggests a possible role for these cells in the pathogenesis of smoking induced airflow limitation.

Role of Ca(2+) and protein kinase C in the serotonin (5-HT) transport in human platelets.

Accumulation of serotonin (5-HT) into human platelets was not affected by the presence of the extra-cellular calcium chelator EGTA, while decreased by platelet incubation with the membrane permeant chelator BAPTA-AM. Serotonin uptake also diminished upon platelet exposure to EGTA/thapsigargin or EGTA/ionomycin which increased the cytosolic [Ca(2+)] to levels lower than those inducing secretion of dense granules. The latter inhibition depended in part on changes of intra-granular pH, since the accumulation of acridine orange, which is driven into the dense granules by the intra-granular acid pH gradient, was slightly decreased in the presence of EGTA/thapsigargin. These compounds also inhibited the 5-HT uptake in platelets pre-incubated with reserpine and bafilomycin that prevent 5-HT from entering into the dense granules. Inhibitors of protease, protein phosphatase, Na(+)/H(+) exchanger or ciclo-oxygenase activities did not modify the serotonin accumulation. Addition of EGTA/thapsigargin to reserpine-treated, [(14)C]5-HT-loaded, platelets caused an imipramine-insensitive release of labelled serotonin. This release was reduced by both BAPTA-AM or protein kinase C inhibitor bisindoylmaleimide (GF). The latter compound, either alone or together with EGTA/thapsigargin, inhibited the 5-HT accumulation in reserpine-treated platelets. It is concluded that both cytosolic [Ca(2+)] and protein kinase C are involved in the regulation of the plasma membrane 5-HT transport.