Expression profiles of hydrophobic surfactant proteins in children with diffuse chronic lung disease

Background

Abnormalities of the intracellular metabolism of the hydrophobic surfactant proteins SP-B and SP-C and their precursors may be causally linked to chronic childhood diffuse lung diseases. The profile of these proteins in the alveolar space is unknown in such subjects.

Methods

We analyzed bronchoalveolar lavage fluid by Western blotting for SP-B, SP-C and their proforms in children with pulmonary alveolar proteinosis (PAP, n = 15), children with no SP-B (n = 6), children with chronic respiratory distress of unknown cause (cRD, n = 7), in comparison to children without lung disease (n = 15) or chronic obstructive bronchitis (n = 19).

Results

Pro-SP-B of 25–26 kD was commonly abundant in all groups of subjects, suggesting that their presence is not of diagnostic value for processing defects. In contrast, pro-SP-B peptides cleaved off during intracellular processing of SP-B and smaller than 19–21 kD, were exclusively found in PAP and cRD. In 4 of 6 children with no SP-B, mutations of SFTPB or SPTPC genes were found. Pro-SP-C forms were identified at very low frequency. Their presence was clearly, but not exclusively associated with mutations of the SFTPB and SPTPC genes, impeding their usage as candidates for diagnostic screening.

Conclusion

Immuno-analysis of the hydrophobic surfactant proteins and their precursor forms in bronchoalveolar lavage is minimally invasive and can give valuable clues for the involvement of processing abnormalities in pediatric pulmonary disorders.     

Activation of Bcl-2-Caspase-9 Apoptosis Pathway in the Testis of Asthmatic Mice

Background

Apoptosis plays a critical role in controlling the proliferation and differentiation of germ cells during spermatogenesis. Dysregulation of the fine-tuned balance may lead to the onset of testicular diseases. In this study, we investigated the activation status of apoptosis pathways in the testicular tissues under the background of an asthmatic mouse model.

Methods

Ten BALB/c mice were divided into two groups: the acute asthma group and the control group. In the acute asthma group, ovalbumin (OVA)-sensitized mice were challenged with aerosolized OVA for 7 days, while the control group was treated with physiological saline. After that, both epididymis and testis were collected to determine the sperm count and motility. Apoptosis in the testis was evaluated by DNA ladder, immunochemistry and further by PCR array of apoptosis-related genes. Finally, the cleavage of caspase-3 and poly ADP-ribose polymerase (PARP) was determined by western blot and the enzymatic activities of caspase-9 and 3/7 were assessed using Caspase-Glo kits.

Results

Compared with control mice, significant decreases in the body weight, testis weight, sperm count and motility were seen in the experimental group. DNA ladder and immunochemistry showed significant increase in apoptotic index of the asthmatic testis, whereas a decrease in mRNA expression of Bcl-2 and increases in Bax, BNIP3, caspase-9, and AIF were observed in the asthma group. Furthermore, protein levels of AIF were significantly upregulated, while the translational expression of Bcl-2 was downregulated markedly. Consistently, caspase-9 activity in the testis of asthma mice was significantly higher than that of the control group.

Conclusion

Collectively, these results showed that Bcl-2-caspase-9 apoptosis pathway was clearly activated in the testis of asthmatic mice with the increased expression of apoptosis-related genes and proteins. To our knowledge, this is the first report demonstrating that asthma could lead to the activation of the mitochondrial apoptosis signaling pathway in the mouse testis.     

Surfactant-Derived Proteins as Markers of Alveolar Membrane Damage in Heart Failure

Background

In heart failure (HF) alveolar-capillary membrane is abnormal. Surfactant-derived proteins (SPs) and plasma receptor for advanced-glycation-end-products (RAGE) have been proposed as lung damage markers.

Methods

Eighty-nine chronic HF and 17 healthy subjects were evaluated by echocardiography, blood parameters, carbon monoxide lung diffusion (DLCO) and cardiopulmonary exercise test. We measured immature SP-B, mature SP-B, SP-A, SP-D and RAGE plasma levels.

Results

Immature SP-B (arbitrary units), mature SP-A (ng/ml) and SP-D (ng/ml), but not mature SP-B (ng/ml) and RAGE (pg/ml) levels, were higher in HF than in controls [immature SP-B: 15.6 (13.1, 75^th–25^th interquartile range) Vs. 11.1 (6.4), p<0.01; SP-A, 29.6 (20.1) Vs. 18.3 (13.5), p = 0.01; SP-D: 125 (90) Vs. 78 (58), p<0.01]. Immature SP-B, SP-A, SP-D and RAGE values were related to DLCO, peak oxygen consumption, ventilatory efficiency, and brain natriuretic peptide (BNP), whereas plasma mature SP-B was not. The DLCO Vs. immature SP-B correlation was the strongest one. At multivariate analysis, RAGE was associated to age and creatinine, SP-A to DLCO and BNP, SP-D to BNP, mature SP-B to DLCO and creatinine, and immature SP-B only but strongly to DLCO.

Conclusions

Immature SP-B is the most reliable biological marker of alveolar-capillary membrane function in HF.     

Expression of Dominant-Negative Thyroid Hormone Receptor Alpha1 in Leydig and Sertoli Cells Demonstrates No Additional Defect Compared with Expression in Sertoli Cells Only

Background

In the testis, thyroid hormone (T3) regulates the number of gametes produced through its action on Sertoli cell proliferation. However, the role of T3 in the regulation of steroidogenesis is still controversial.

Methods

The TRα^AMI knock-in allele allows the generation of transgenic mice expressing a dominant-negative TRα1 (thyroid receptor α1) isoform restricted to specific target cells after Cre-loxP recombination. Here, we introduced this mutant allele in both Sertoli and Leydig cells using a novel aromatase-iCre (ARO-iCre) line that expresses Cre recombinase under control of the human Cyp19(IIa)/aromatase promoter.

Findings

We showed that loxP recombination induced by this ARO-iCre is restricted to male and female gonads, and is effective in Sertoli and Leydig cells, but not in germ cells. We compared this model with the previous introduction of TRα^AMI specifically in Sertoli cells in order to investigate T3 regulation of steroidogenesis. We demonstrated that TRα^AMI-ARO males exhibited increased testis weight, increased sperm reserve in adulthood correlated to an increased proliferative index at P3 in vivo, and a loss of T3-response in vitro. Nevertheless, TRα^AMI-ARO males showed normal fertility. This phenotype is similar to TRα^AMI-SC males. Importantly, plasma testosterone and luteinizing hormone levels, as well as mRNA levels of steroidogenesis enzymes StAR, Cyp11a1 and Cyp17a1 were not affected in TRα^AMI-ARO.

Conclusions/Significance

We concluded that the presence of a mutant TRα^AMI allele in both Leydig and Sertoli cells does not accentuate the phenotype in comparison with its presence in Sertoli cells only. This suggests that direct T3 regulation of steroidogenesis through TRα1 is moderate in Leydig cells, and that Sertoli cells are the main target of T3 action in the testis.     

GPR30, the non-classical membrane G protein related estrogen receptor, is overexpressed in human seminoma and promotes seminoma cell proliferation

Background

Testicular germ cell tumours are the most frequent cancer of young men with an increasing incidence all over the world. Pathogenesis and reasons of this increase remain unknown but epidemiological and clinical data have suggested that fetal exposure to environmental endocrine disruptors (EEDs) with estrogenic effects, could participate to testicular germ cell carcinogenesis. However, these EEDs (like bisphenol A) are often weak ligands for classical nuclear estrogen receptors. Several research groups recently showed that the non classical membrane G-protein coupled estrogen receptor (GPER/GPR30) mediates the effects of estrogens and several xenoestrogens through rapid non genomic activation of signal transduction pathways in various human estrogen dependent cancer cells (breast, ovary, endometrium). The aim of this study was to demonstrate that GPER was overexpressed in testicular tumours and was able to trigger JKT-1 seminoma cell proliferation.

Results

We report here for the first time a complete morphological and functional characterization of GPER in normal and malignant human testicular germ cells. In normal adult human testes, GPER was expressed by somatic (Sertoli cells) and germ cells (spermatogonia and spermatocytes). GPER was exclusively overexpressed in seminomas, the most frequent testicular germ cell cancer, localized at the cell membrane and triggered a proliferative effect on JKT-1 cells in vitro, which was completely abolished by G15 (a GPER selective antagonist) and by siRNA invalidation.

Conclusion

These results demonstrate that GPER is expressed by human normal adult testicular germ cells, specifically overexpressed in seminoma tumours and able to trigger seminoma cell proliferation in vitro. It should therefore be considered rather than classical ERs when xeno-estrogens or other endocrine disruptors are assessed in testicular germ cell cancers. It may also represent a prognosis marker and/or a therapeutic target for seminomas.     

Expression and localization of surfactant proteins in human nasal epithelium

Surfactant proteins (SPs), designated SP-A, SP-B, SP-C, and SP-D, play an important role in surfactant metabolism and host defense mechanisms in the lung. This study investigates expression of the different SP types in human nasal mucosa and cultured normal human nasal epithelial (NHNE) cells and whether the expression of SP mRNA is influenced by the degree of mucociliary differentiation. RT-PCR was performed with mRNA from cultured NHNE cells and nasal mucosa. Immunohistochemical staining for SPs was performed on nasal mucosa specimens. Western blot analysis was performed on cell lysates from cultured NHNE cells. SP-A2, SP-B, and SP-D mRNAs were expressed in normal NHNE cells and human nasal mucosa. SPs were localized in ciliated cells of the surface epithelium and serous acini of the submucosal glands. SP-A, SP-B, and SP-D proteins were expressed in cultured NHNE cells. The degree of mucociliary differentiation influenced expression of the SP gene. We demonstrate that SP-A, SP-B, and SP-D are expressed in human nasal mucosa and cultured NHNE cells. Further study of the functional role of SPs in the upper airway is required.     

Inhibition of NOS-NO System Prevents Autoimmune Orchitis Development in Rats: Relevance of NO Released by Testicular Macrophages in Germ Cell Apoptosis and Testosterone Secretion

Background

Although the testis is considered an immunoprivileged organ it can orchestrate immune responses against pathological insults such as infection and trauma. Experimental autoimmune orchitis (EAO) is a model of chronic inflammation whose main histopathological features it shares with human orchitis. In EAO an increased number of macrophages infiltrate the interstitium concomitantly with progressive germ cell degeneration and impaired steroidogenesis. Up-regulation of nitric oxide (NO)-NO synthase (NOS) system occurs, macrophages being the main producers of NO.

Objective

The aim of our study was to evaluate the role of NO-NOS system in orchitis development and determine the involvement of NO released by testicular macrophages on germ cell apoptosis and testosterone secretion.

Method and Results

EAO was induced in rats by immunization with testicular homogenate and adjuvants (E group) and a group of untreated normal rats (N) was also studied. Blockage of NOS by i.p. injection of E rats with a competitive inhibitor of NOS, L-NAME (8mg/kg), significantly reduced the incidence and severity of orchitis and lowered testicular nitrite content. L-NAME reduced germ cell apoptosis and restored intratesticular testosterone levels, without variations in serum LH. Co-culture of N testicular fragments with testicular macrophages obtained from EAO rats significantly increased germ cell apoptosis and testosterone secretion, whereas addition of L-NAME lowered both effects and reduced nitrite content. Incubation of testicular fragments from N rats with a NO donor DETA-NOnoate (DETA-NO) induced germ cell apoptosis through external and internal apoptotic pathways, an effect prevented by N-acetyl-L-cysteine (NAC). DETA-NO inhibited testosterone released from Leydig cells, whereas NAC (from 2.5 to 15 mM) did not prevent this effect.

Conclusions

We demonstrated that NO-NOS system is involved in the impairment of testicular function in orchitis. NO secreted mainly by testicular macrophages could promote oxidative stress inducing ST damage and interfering in Leydig cell function.     

Human testis-expressed sequence 101 is limitedly distributed in germinal epithelium of testis and disappears in seminoma

Background

Testis-expressed sequence 101 (TEX101) was found to be highly expressed in testis and involved in acrosome reaction in previous studies. Recently, the metastasis suppressor function of TEX101 in cancer was disclosed, but the comprehensive investigation of its expression has rarely been reported. In this study, the expression features of TEX101 in normal human organs and seminoma were systematically analyzed.

Results

Immunohistochemistry demonstrated intense staining of TEX101 in human testis tissues; however, its expression in 27 other types of normal human organs, including the ovary, was negligible. Higher expression of TEX101 was observed in the spermatocytes and spermatids of the testis, but relatively lower staining was detected in spermatogonia. Western blotting showed a single TEX101 band of 38 kDa in human testis, but it did not correspond to the predicted molecular weight of its mature form at 21 KDa. Furthermore, we examined seminoma tissues by immunohistochemistry and found that none of the 36 samples expressed TEX101.

Conclusions

Our data confirmed TEX101 to be a testis protein that could be related to the maturation process of male germ cells. The lack of TEX101 in seminoma indicated its potential role in tumor progression. This characteristic expression of TEX101 could provide a valuable reference for understanding its biological functions.     

Arecoline induces TNF-alpha production and Zonula Occludens-1 redistribution in mouse Sertoli TM4 cells

Background

Arecoline, a major alkaloid in Areca nut has the ability to induce oxidative stress. The effect of Areca nut, arecoline on reducing sperm quality and quantity were documented previously using several animal models. Junction disruption by down-regulation of the junction-adhesive protein via oxidative stress is an important route mediating abnormal spermatogenesis. Therefore, in this present study, we investigated the functional role of arecoline on junctional proteins.

Results

To analyze direct effects of arecoline on testis cells, confluent mouse testicular Sertoli cell line TM4 was exposed to arecoline. Arecoline decreased insoluble zonula occludens-1 (ZO-1) protein expression in TM4 cells, however, arecoline treatment increased TNF-alpha production in both TM4 and monocytic THP1 cells. In addition, ERK1/2 inhibitor PD98059 reversed arecoline effects on TNF-alpha and ZO-1.

Conclusions

Arecoline increases the production of TNF-alpha and induces protein redistribution of ZO-1. All these results explain the role of arecoline in male reproductive dysfunction, besides its cytotoxic induction.

Electronic supplementary material

The online version of this article (doi:10.1186/s12929-014-0093-z) contains supplementary material, which is available to authorized users.     

Onco-testicular sperm extraction (Onco-TESE) from a single testis with metachronous bilateral testicular cancer: a case report

Background

Although oncologic testicular sperm extraction (onco-TESE) has been increasingly practiced, the evidence of onco-TESE performed in patients with testicular cancer is insufficient. Furthermore, in bilateral testicular cancer, accounting for 0.5%–1% of testicular cancers, onco-TESE is more challenging and has been insufficiently reported.

Case presentation

Here we report the case of a 25-year-old man who underwent onco-TESE from his residual single testis with a nonseminomatous germ cell tumor that occurred 5 years after orchiectomy of the contralateral testis. A second orchiectomy and simultaneous TESE from the noncancerous testicular tissue were performed. The pathological diagnosis was germ cell tumors, tumors of more than one histological type (embryonal carcinoma, immature teratoma, yolk sac tumor, seminoma, and choriocarcinoma; pT1N0M0). The patient subsequently married and hoped for fatherhood 3 years later. Whereas histological diagnosis of the normal testicular tissue was Johnsen score 6 (maturation arrest), morphologically normal and motile sperms were successfully retrieved from thawed TESE samples and used for multiple cycles of intracytoplasmic sperm injection. Although the conception has not been succeeded to date, ICSI attempts have been continuing.

Conclusion

This case demonstrates the effectiveness of onco-TESE for challenging cases such as bilateral and nonseminmatous testicular cancer.

     

H-rev107 regulates prostaglandin D2 synthase-mediated suppression of cellular invasion in testicular cancer cells

Background

H-rev107 is a member of the HREV107 type II tumor suppressor gene family which includes H-REV107, RIG1, and HRASLS. H-REV107 has been shown to express at high levels in differentiated tissues of post-meiotic testicular germ cells. Prostaglandin D2 (PGD2) is conjectured to induce SRY-related high-mobility group box 9 (SOX9) expression and subsequent Sertoli cell differentiation. To date, the function of H-rev107 in differentiated testicular cells has not been well defined.

Results

In the study, we found that H-rev107 was co-localized with prostaglandin D2 synthase (PTGDS) and enhanced the activity of PTGDS, resulting in increase of PGD2 production in testis cells. Furthermore, when H-rev107 was expressed in human NT2/D1 testicular cancer cells, cell migration and invasion were inhibited. Also, silencing of PTGDS would reduce H-rev107-mediated increase in PGD2, cAMP, and SOX9. Silencing of PTGDS or SOX9 also alleviated H-rev107-mediated suppression of cell migration and invasion.

Conclusions

These results revealed that H-rev107, through PTGDS, suppressed cell migration and invasion. Our data suggest that the PGD2-cAMP-SOX9 signal pathway might play an important role in H-rev107-mediated cancer cell invasion in testes.     

3640 Unique EST Clusters from the Medaka Testis and Their Potential Use for Identifying Conserved Testicular Gene Expression in Fish and Mammals

Background

The fish medaka is the first vertebrate capable of full spermatogenesis in vitro from self-renewing spermatogonial stem cells to motile test-tube sperm. Precise staging and molecular dissection of this process has been hampered by the lack of suitable molecular markers.

Methodology and Principal Findings

We have generated a normalized medaka testis cDNA library and obtained 7040 high quality sequences representing 3641 unique gene clusters. Among these, 1197 unique clusters are homologous to known genes, and 2444 appear to be novel genes. Ontology analysis shows that the 1197 gene products are implicated in diverse molecular and cellular processes. These genes include markers for all major types of testicular somatic and germ cells. Furthermore, markers were identified for major spermatogenic stages ranging from spermatogonial stem cell self-renewal to meiosis entry, progression and completion. Intriguingly, the medaka testis expresses at least 13 homologs of the 33 mouse X-chromosomal genes that are enriched in the testis. More importantly, we show that key components of several signaling pathways known to be important for testicular function in mammals are well represented in the medaka testicular EST collection.

Conclusions/Significance

Medaka exhibits a considerable similarity in testicular gene expression to mammals. The medaka testicular EST collection we obtained has wide range coverage and will not only consolidate our knowledge on the comparative analysis of known genes'' functions in the testis but also provide a rich resource to dissect molecular events and mechanism of spermatogenesis in vivo and in vitro in medaka as an excellent vertebrate model.     

Critical Structural and Functional Roles for the N-Terminal Insertion Sequence in Surfactant Protein B Analogs

Background

Surfactant protein B (SP-B; 79 residues) belongs to the saposin protein superfamily, and plays functional roles in lung surfactant. The disulfide cross-linked, N- and C-terminal domains of SP-B have been theoretically predicted to fold as charged, amphipathic helices, suggesting their participation in surfactant activities. Earlier structural studies with Mini-B, a disulfide-linked construct based on the N- and C-terminal regions of SP-B (i.e., ∼residues 8–25 and 63–78), confirmed that these neighboring domains are helical; moreover, Mini-B retains critical in vitro and in vivo surfactant functions of the native protein. Here, we perform similar analyses on a Super Mini-B construct that has native SP-B residues (1–7) attached to the N-terminus of Mini-B, to test whether the N-terminal sequence is also involved in surfactant activity.

Methodology/Results

FTIR spectra of Mini-B and Super Mini-B in either lipids or lipid-mimics indicated that these peptides share similar conformations, with primary α-helix and secondary β-sheet and loop-turns. Gel electrophoresis demonstrated that Super Mini-B was dimeric in SDS detergent-polyacrylamide, while Mini-B was monomeric. Surface plasmon resonance (SPR), predictive aggregation algorithms, and molecular dynamics (MD) and docking simulations further suggested a preliminary model for dimeric Super Mini-B, in which monomers self-associate to form a dimer peptide with a “saposin-like” fold. Similar to native SP-B, both Mini-B and Super Mini-B exhibit in vitro activity with spread films showing near-zero minimum surface tension during cycling using captive bubble surfactometry. In vivo, Super Mini-B demonstrates oxygenation and dynamic compliance that are greater than Mini-B and compare favorably to full-length SP-B.

Conclusion

Super Mini-B shows enhanced surfactant activity, probably due to the self-assembly of monomer peptide into dimer Super Mini-B that mimics the functions and putative structure of native SP-B.     

Infectivity of adeno-associated virus serotypes in mouse testis

Background

Recombinant adeno-associated viruses (AAVs) are emerging as favoured transgene delivery vectors for both research applications and gene therapy. In this context, a thorough investigation of the potential of various AAV serotypes to transduce specific cell types is valuable. Here, we rigorously tested the infectivity of a number of AAV serotypes in murine testis by direct testicular injection.

Results

We report the tropism of serotypes AAV2, 5, 8, 9 and AAVrh10 in mouse testis. We reveal unique infectivity of AAV2 and AAV9, which preferentially target intertubular testosterone-producing Leydig cells. Remarkably, AAV2 TM, a mutant for capsid designed to increase transduction, displayed a dramatic alteration in tropism; it infiltrated seminiferous tubules unlike wildtype AAV2 and transduced Sertoli cells. However, none of the AAVs tested infected spermatogonial cells.

Conclusions

In spite of direct testicular injection, none of the tested AAVs appeared to infect sperm progenitors as assayed by reporter expression. This lends support to the current view that AAVs are safe gene-therapy vehicles. However, testing the presence of rAAV genomic DNA in germ cells is necessary to assess the risk of individual serotypes.

     

Complement Activation in Patients with Focal Segmental Glomerulosclerosis

Background

Recent pre-clinical studies have shown that complement activation contributes to glomerular and tubular injury in experimental FSGS. Although complement proteins are detected in the glomeruli of some patients with FSGS, it is not known whether this is due to complement activation or whether the proteins are simply trapped in sclerotic glomeruli. We measured complement activation fragments in the plasma and urine of patients with primary FSGS to determine whether complement activation is part of the disease process.

Study Design

Plasma and urine samples from patients with biopsy-proven FSGS who participated in the FSGS Clinical Trial were analyzed.

Setting and Participants

We identified 19 patients for whom samples were available from weeks 0, 26, 52 and 78. The results for these FSGS patients were compared to results in samples from 10 healthy controls, 10 patients with chronic kidney disease (CKD), 20 patients with vasculitis, and 23 patients with lupus nephritis.

Outcomes

Longitudinal control of proteinuria and estimated glomerular filtration rate (eGFR).

Measurements

Levels of the complement fragments Ba, Bb, C4a, and sC5b-9 in plasma and urine.

Results

Plasma and urine Ba, C4a, sC5b-9 were significantly higher in FSGS patients at the time of diagnosis than in the control groups. Plasma Ba levels inversely correlated with the eGFR at the time of diagnosis and at the end of the study. Plasma and urine Ba levels at the end of the study positively correlated with the level of proteinuria, the primary outcome of the study.

Limitations

Limited number of patients with samples from all time-points.

Conclusions

The complement system is activated in patients with primary FSGS, and elevated levels of plasma Ba correlate with more severe disease. Measurement of complement fragments may identify a subset of patients in whom the complement system is activated. Further investigations are needed to confirm our findings and to determine the prognostic significance of complement activation in patients with FSGS.