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PubMed2002

An immunohistochemical and ultrastructural study of syringocystadenoma papilliferum.

BACKGROUND: Syringocystadenoma papilliferum is a benign hamartomatous tumour of the skin. The histogenesis of this tumour is still controversial. There have been few reports regarding immunohistochemical investigations using only a limited range of antibodies and ultrastructural studies on this rare tumour. OBJECTIVES: To elucidate the immunohistochemical and ultrastructural properties of this tumour. METHODS: We investigated the immunohistological patterns of 12 different anticytokeratin (CK) antibodies and several other markers in five cases of this tumour, comparing them with the patterns in adult sweat glands. One of these cases was also evaluated ultrastructurally. RESULTS: The luminal columnar cells of the tumour were mostly positive for CK7 and more than 70% were positive for CK19. These cells showed the heterogeneous expression of CK1/5/10/14, CK14 and CK5/8. These patterns were also observed in the luminal cells in the secretory or the ductal portion of the adult sweat glands. The basal cuboidal cells of the tumour almost constantly expressed CK1/5/10/14, CK5/8, CK14 and CK7 (except for one case), similar to the patterns of basal cells in the transitional portion and myoepithelial cells in the sweat glands. However, the basal tumour cells expressed CK19 and vimentin heterogeneously, and alpha-smooth muscle actin focally (three cases). Ultrastructurally, the constituent epithelial cells were mainly divided into three types: luminal cells, basal cells and clear cells. The luminal tumour cells bore features of the secretory or ductal luminal cells of sweat glands, although they were somewhat immature in appearance. The basal tumour cells were fundamentally basaloid in nature. The clear cells were undifferentiated or primitive in appearance, suggesting stem or progenitor cell properties. Transitional forms between the clear cells and the other two cell types were also identified. CONCLUSIONS: The tumour epithelium was composed of several cell types demonstrating various developmental stages from the primitive clear cells to the basal cells demonstrating a tendency to differentiate toward basal cells in the apocrine transitional portion or myoepithelial lineage, or luminal cells toward the ductal or secretory epithelium. These results support the classical concept that syringocystadenoma papilliferum is a hamartomatous tumour that arises from pluripotent cells.

Adenoma, Sweat Gland↗

PubMed1999

Nitric oxide protects the ultrastructure of pancreatic acinar cells in the course of caerulein-induced acute pancreatitis.

Nitric oxide (NO) as a unique biological mediator that has been implicated in many physiological and pathophysiological processes may have a significant influence on the course of acute pancreatitis and the recovery process. The aim of the study was to evaluate the effect of a NO synthase inhibitor or a substrate for NO endogenous production on the ultrastructural features of the acinar cells in the course of caerulein-induced acute pancreatitis. Acute pancreatitis was induced in the rats by a supramaximal dose of caerulein. During acute pancreatitis induction, the rats were treated with L-arginine (the substrate for NO synthesis), NG-nitro-L-arginine (L-NNA, NO synthase inhibitor), L-arginine + L-NNA or saline. Light and electron microscopy examinations were performed in all groups after pancreatitis induction and additionally after 7 and 14 days of recovery. The study demonstrated that the NO synthase inhibitor given during pancreatitis induction in rats enhances the damage to the acinar cells, detected ultrastructurally, and increases the cellular inflammatory infiltration. In the later period, the considerable damage to the mitochondria and the changes in secretory compartment were observed, including dilated cisternae of Golgi apparatus, focal degranulation of rough endoplasmic reticulum, and reduced number of zymogen granules and condensing vacuoles. L-arginine reversed to some extent the deleterious effect of L-NNA, although when administered alone it had no apparent effect on the ultrastructure of pancreatic acinar cells compared with untreated animals. The obtained results indicate that the NO synthase inhibitor enhances the ultrastructural degenerative alterations in the pancreatic acinar cells in the course of caerulein-induced acute pancreatitis and confirm the protective role of endogenous nitric oxide in this disease.

Acute Disease↗

PubMed2002

Changes in ultrastructure and the occurrence of permeability transition in mitochondria during rat liver regeneration.

Mitochondrial bioenergetic impairment has been found in the organelles isolated from rat liver during the prereplicative phase of liver regeneration. To gain insight into the mechanism underlying this impairment, we investigated mitochondrial ultrastructure and membrane permeability properties in the course of liver regeneration after partial hepatectomy, with special interest to the role played by Ca2+ in this process. The results show that during the first day after partial hepatectomy, significant changes in the ultrastructure of mitochondria in situ occur. Mitochondrial swelling and release from mitochondria of both glutamate dehydrogenase and aspartate aminotransferase isoenzymes with an increase in the mitochondrial Ca2+ content were also observed. Cyclosporin-A proved to be able to prevent the changes in mitochondrial membrane permeability properties. At 24 h after partial hepatectomy, despite alteration in mitochondrial membrane permeability properties, no release of cytochrome c was found. The ultrastructure of mitochondria, the membrane permeability properties and the Ca2+ content returned to normal values during the replicative phase of liver regeneration. These results suggest that, during the prereplicative phase of liver regeneration, the changes in mitochondrial ultrastructure observed in liver specimens were correlated with Ca2+-induced permeability transition in mitochondria.

Animals↗

PubMed2002

Effects of bovine serum albumin and estrous cow serum on development and ultrastructure of in vitro-produced porcine embryos.

This study evaluated the effects of bovine serum albumin (BSA; 4 mg/ml) and estrous cow serum (ECS; 10%) in North Carolina State University (NCSU) 23 medium on the development of in vitro-matured and in vitro-fertilized porcine oocytes. Early cleavage rate was significantly (P < 0.05) higher in NCSU/ECS (71.3 +/- 14.7%) vs. NCSU/BSA (60.6 +/- 4.7%). Cleavage beyond the four-cell stage was not different between the two culture media (43.5 +/- 9.5% and 41.4 +/- 17.7%, respectively). The proportion of development to blastocysts was--with borderline significance (P = 0.05)--higher in NCSU/BSA (28.0 +/- 4.4%) than in NCSU/ECS (20.4 +/- 7.3%). Blastocysts produced in NCSU/BSA had significantly (P < 0.001) higher cell numbers than those cultured in NCSU/ECS (29.5 +/- 20.1 vs. 16.9 +/- 10.8). The ultrastructure of in vitro-produced blastocysts from both culture systems was compared vs. in vivo-derived blastocysts. The latter showed a clear differentiation between trophectoderm (TE) and inner cell mass (ICM) cells. The TE cells were anchored to other TE cells or ICM cells by long, well-developed junctional complexes. The apical membrane of trophoblast cells was covered with numerous microvilli. Mitochondria were abundant, round to elongated in shape, and showed clear transverse cristae. The ultrastructure of blastocysts cultured in NCSU/BSA mimicked that of in vivo-derived embryos closely. In contrast, blastocysts from the NCSU/ECS culture system displayed an irregular ultrastructure with reduced numbers of organelles and numerous cytoplasmic inclusions, such as lipid-yolk-vacuoles and vacuoles with lipid content. In some sections of these embryos, cellular debris was detected in cytoplasm. The shape of mitochondria was more ovoid and cristae were not visible. In summary, our results demonstrate a beneficial influence of ECS in the culture medium on initial cleavage of in vitro-produced porcine embryos. Clearly negative effects of ECS in the subsequent culture period are associated with marked ultrastructural changes of embryonic cells.

Animals↗

PubMed2003

A prospective evaluation of detrusor ultrastructural changes in bladder outlet obstruction.

OBJECTIVES: To characterize the ultrastructure of detrusor smooth muscle from the bladders of symptomatic men with bladder outlet obstruction (BOO) caused by benign prostatic enlargement (BPE) and compare this with a matched control group; to determine how detrusor morphology relates to urodynamic findings and to develop a better understanding of the natural development of bladder dysfunction related to BOO. PATIENTS AND METHODS: Twelve men (mean age 66 years, range 52-77) with urodynamically confirmed BOO caused by BPE and 12 age-matched asymptomatic normally voiding controls (mean age 67.8 years, undergoing cystoscopy for other conditions) had detrusor biopsies taken endoscopically. The biopsies were processed for electron microscopy using standard methods. The specimens were randomized and examined at medium power (x 4000) by an examiner unaware of the urodynamic findings. Any ultrastructural patterns identified subjectively were noted. RESULTS: In the BOO group eight of the 12 men had a myohypertrophic pattern, half of which were associated with a degenerative pattern of hypocontractility. Of the remaining four patients, two had the degenerative pattern alone and two were normal. The six men whose biopsies had a degenerative pattern had consistent postvoid residual volumes of > 150 mL; the remainder all had volumes of < 150 mL. There were no ultrastructural abnormalities in the control patients. CONCLUSIONS: There are interesting qualitative ultrastructural changes in the obstructed detrusor, but they are not consistent enough to provide a reliable diagnostic tool. However, there may be an important relationship between the degenerative pattern and postvoid residual volume in BOO.

Adult↗

PubMed1998

Haemodynamic and ultrastructural observations on the rat liver after two-thirds partial hepatectomy.

Rat liver ultrastructure was investigated after partial hepatectomy (PH), by scanning and transmission electron microscopy. Portal pressure was monitored before and after PH and, after killing performed at 6, 12, 24, 48 h and 10 d, regenerating livers were fixed by portal vein perfusion under haemodynamic conditions identical to those existing in vivo. An early and persistent increase in portal pressure after PH was found (P < 0.01 for normal vs sham-operated controls). Ultrastructural study showed sinusoid dilatation and disappearance of the sieve-plate arrangement of small endothelial pores, thus leaving the parenchymal liver cell surface directly exposed to portal blood. Widening of sinusoids, endothelial fenestrations, intercellular spaces and spaces of Disse, was accompanied by dilatation of bile canaliculi. At 10 d, liver ultrastructure had returned to normal. Our observations suggest that a rise in portal pressure, as a consequence of PH, may be related to the observed ultrastructural changes in the liver.

Animals↗

PubMed1999

Ultrastructural features of goat oviductal secretory cells at follicular and luteal phases of the oestrous cycle.

The aim of the present study was to investigate the ultrastructure of secretory cells in the various regions of the goat oviduct during the follicular and luteal phases of the oestrous cycle. During the follicular phase in the fimbriae, the secretory cells contained small secretory granules with electron-dense matrices. In the luteal phase, the secretory granules disappeared and cytoplasmic protrusions, extending beyond the luminal border of the ciliated cells and often containing the nucleus, were predominant. During the follicular phase in ampullary secretory cells, numerous secretory granules with moderately electron-dense matrices were present in the supranuclear cytoplasm and exocytosis of secretory granules was observed. The number of secretory granules was dramatically reduced in the ampullary secretory cells at the luteal phase. Conspicuous cytoplasmic protrusions of secretory cells were observed similar to those of the fimbrial epithelium. Isthmic cells were almost free of secretory granules and lysosome-like bodies were found both at the follicular and luteal phases. In conclusion, our ultrastructural observations of goat oviduct revealed marked cyclic changes in the ultrastructural features of secretory cells and the ultrastructural features and the numbers of secretory granules were distinctive for each particular segment.

Animals↗

PubMed2002

Ultrastructural changes in malignant transformation of oral mucosa.

Transmission electron microscopy (EM) has been used to identify the ultrastructural details of normal and cancerous human oral mucosa. However, inconsistent reports of structural descriptions have rendered transmission EM valueless in the diagnosis of oral squamous cell carcinoma (SCC) or as a prognostic indicator. To identify features of dysplasia for diagnostic purposes, normal mucosa, severe dysplasia, oral SCC and normal margin adjacent to oral SCC were used to compare the ultrastructural features of normal and premalignant oral mucosa and oral SCC. The preparatory stages of dehydration, embedding, cutting and positive staining for transmission EM were modified and tested to improve ultrastructural definition. Thin and discontinuous basal laminas were found in mucosa with severe dysplasia and normal margin adjacent to oral SCC. No basal lamina was identified in oral SCC. This study has shown that there are some ultrastructural changes during malignant transformation of oral mucosa. Together with other laboratory investigative techniques, transmission EM may be helpful in detecting malignant changes in oral mucosa.

Acrylic Resins↗

PubMed1983

Functional and ultrastructural changes induced by short term ovariectomy on pancreatic islets.

The effect of short term ovariectomy and combined estrogen-progesterone treatment on insulin secretion was studied and related to the changes observed in the glucose oxidation, calcium uptake and insulin content, as well as the ultrastructure of pancreatic rat islets. It was found that ovariectomy was followed by an enhanced glucose-induced insulin secretion, glucose oxidation, calcium uptake and insulin content together with striking changes at the ultrastructural level located only in the B cell population. They were represented by the appearance of broad cytoplasmic areas containing an homogeneous fine granular material, enclosing sometimes organelles, B secretory granules with their clear halo significantly enlarged and marked dilation of the rough endoplasmic reticulum. Conversely, in ovariectomized-rats supplemented with estrogen-progesterone, the insulin response as well as the above mentioned metabolic parameters return to normal control values. Although not completely, ultrastructural changes also showed a clear amelioration. On account of our results, we might suggest that insulin secretion is controlled, at least in part, by the circulating levels of estrogen and progesterone throughout their effect on pancreatic islet metabolism. The absence of this control over a short term period produces a reversible increment in B cell function and the appearance of important changes at the ultrastructural level.

Animals↗

PubMed1986

[Ultrastructural changes in skeletal muscle in polymyalgia rheumatica].

Skeletal muscle from 21 patients with clinical confirmed polymyalgia rheumatica (PMR) were examined electronmicroscopically. The changes were classified according to 15 ultrastructure criteria. The focal changes have a regressive character and, while they are nonspecific, the systematic assessment of all criteria produced a characteristic pattern in which the ultrastructural picture of skeletal muscles provided a certain profile in cases of PMR. The functionally most important ultrastructural change concerns the mitochondria. Deposition and deformation of crystals result in mitochondrial changes which are structurally definable and are harmful to cell respiration. They are compensated by new formation and accumulation of mitochondria. Comparative analysis of regressive skeletal changes and of processes in the region of the media of the muscular arteries demonstrates analogous morphological changes which point to a common harmful and overlying systemic process in PMR and giant cell arteritis. Changes in the ultrastructure of the kind and degree described cannot be explained by inflammatory or noninflammatory arterial occlusions.

Humans↗

PubMed2002

Ultrastructural characterization of developmental and degenerative vitreo-retinal changes in the eyes of transgenic mice with a deletion mutation in type II collagen gene.

PURPOSE: Molecular genetic analyses have clearly associated vitreoretinal degeneration with mutations in the type II collagen gene, but lack of experimental models has prevented systematic analyses of the occurrence of phenotypic changes and of the pathogenetic mechanisms involved. The present study is a detailed morphological and ultrastructural analysis of the vitreoretinal consequences of a small deletion mutation in the type II collagen gene. METHODS: The eyes of Del1 mice carrying six copies of pro alpha1(II) collagen transgene with a small deletion mutation were analyzed during embryonic development, postnatal growth and aging using their nontransgenic littermates as controls. Tissue samples were processed for light and electron microscopy for morphological and ultrastructural analyses. Transcription of pro alpha1(II) collagen gene was localized by in situ hybridization, and type II collagen was detected by immunohistochemistry. RESULTS: In this mouse model most components of the eye are ultrastructurally unaltered. However, the transgenes caused a dose-dependent dominant negative effect seen as a reduced number of type II collagen fibrils in the vitreous. In concert with this, dose-dependent accumulation of amorphous material was observed in the dilated rough endoplasmic reticulum of cells responsible for the production of type II collagen molecules. In mice homozygous for the transgene locus, the vitreoretinal degenerative lesions appeared already during late embryonic development. In mice heterozygous for the locus, such changes were milder and appeared only during postnatal growth and progressed gradually upon aging. CONCLUSIONS: The observed ultrastructural changes suggest that defective structure and function of collagen fibrils in Del1 mice result from a partial block in the post-translational processing and secretion of the mutated procollagen chains, and partly from secretion of mutated procollagen molecules which interfere with normal fibrillogenesis.

Aging↗

PubMed2001

Chylomicron retention disease--the role of ultrastructural examination in differential diagnosis.

Three children with malabsorption presumably caused by celiac disease had undergone jejunal biopsy. While a histological examination revealed microvacuolization of enterocytes in the absence of celiac lesions, an ultrastructural investigation disclosed numerous chylomicrons and larger lipid vacuoles inside the cytoplasm of enterocytes, mostly in the supranuclear region. No chylomicrons were evident in the interstitium between adjacent enterocytes, as observed in normal subjects. These ultrastructural findings allowed for the diagnosis of "Chylomicron retention disease" (CRD). CRD was described for the first time by Anderson in 1961, and it is included in the group of disorders of biosynthesis and secretion of B apolipoproteins (apoB). This disease, in particular, appears to result from a specific defect involving the secretion of lipoproteins containing apoB-48 from the gut, with the complete absence of post prandial chylomicrons in the sera. CRD needs to be recognized early because of its adverse effects on growth and its potential for neurological and ocular complications, and the ultrastructural identification of chylomicron-size lipid droplets clustered in the enterocytes, with the absence of fat outside the cells, represents the gold standard to identify CRD. together with clinical aspects and laboratory measurements. In this study, we describe the histological and ultrastructural aspects observed in three pediatric cases of CRD.

Apolipoproteins B↗

PubMed2002

Cholestatic effect of large bilirubin loads and cholestasis protection conferred by cholic acid co-infusion: a molecular and ultrastructural study.

BACKGROUND: Large intravenous bilirubin loads block biliary phospholipid secretion, produce canalicular membrane lesions and cause canalicular cholestasis. Cholic acid co-infusion forestalls these untoward effects. The aim of this study was first to determine whether bilirubin overload causes cholestasis through reducing the activity or the hepatic expression of the bile salt export pump (bsep) or Na-taurocholate co-transporting polypeptide (ntcp) and, secondly, whether cholic acid co-infusion forestalls cholestasis by upregulating bsep, ntcp or phosphoglycoprotein 3 (pgp3) expressions or activities. A further aim was to determine whether large bilirubin infusions also produce ultrastructural changes inside hepatocytes. METHODS: The effects of intravenous infusion of 2 g bilirubin over 150 min on hepatic expression of bsep, ntcp and pgp3 were studied in bile acid-depleted and cholic acid co-infused pigs, and related to canalicular bile acid transport and bile secretion. Effects on hepatocyte ultrastructural morphology were analysed by electron microscopy. RESULTS: Bilirubin-induced cholestasis reflected marked diminution of bsep and pgp3 transport activities and not reduced hepatic expression of these transporters. Hepatocyte ultrastructural abnormalities were predominantly confined to the hepatocyte canalicular membrane in cholestatic livers. Cholic acid co-infusion with bilirubin conferred complete cholestasis protection through enhancing pgp3 and bsep transporter activities and not through upregulating their expression. Bilirubin infusion did not change ntcp expression. CONCLUSION: Bilirubin-induced cholestasis is due to markedly impaired activity of the membrane-embedded bsep transporter consequent upon ultrastructural injury to the canalicular membrane. Cholic acid co-infusion with bilirubin enhances bsep and pgp3 activities and confers protection against canalicular membrane injury and bilirubin-induced cholestasis.

ATP Binding Cassette Transporter, Subfamily B↗

PubMed2003

The detrusor muscle cell in bladder outlet obstruction--ultrastructural and morphometric findings.

OBJECTIVE: Lower urinary tract symptoms (LUTS) in elderly males are not solely caused by bladder outlet obstruction (BOO) and may be at least partly attributable to detrusor dysfunction. Urodynamically, patients may show instability, hypocontractility, BOO or combinations of these findings. These findings have been related to specific ultrastructural changes in detrusor smooth muscle cells; however, this relationship is controversial. The aim of this study was to correlate ultrastructural findings in patients with BOO with urodynamic parameters. MATERIAL AND METHODS: In 25 men with BOO verified by means of a full urodynamic evaluation, including a pressure-flow study, a detrusor biopsy was obtained. Six men without BOO served as controls. Biopsies for electron microscopy were analysed semiquantitatively and morphometrically to determine the presence of muscle cell hypertrophy, variation in intercellular distances, occurrence of abnormal cell junctions and configurations and intracellular changes. RESULTS: The only parameter which was found to relate to the degree of obstruction in BOO was an increase in intra- and interfascicular elastin, all other correlations not reaching significance. CONCLUSION: This study does not confirm a specific relationship between ultrastructural detrusor smooth muscle features and various types of BOO. Therefore ultrastructural investigation of detrusor smooth muscle cells cannot replace urodynamic evaluation in the classification of LUTS.

Adult↗

PubMedDate not supplied

Fibrosarcoma mimicking plasmacytoma or carcinoma: an ultrastructural study of 4 cases.

Because the fibroblast has a remarkable capability of phenotypic modulations, reflected in both morphologic and immunohistochemical (IHC) changes, ultrastructural studies are mandatory to identify the variants of fibroblasts. Myofibroblasts or histiofibroblasts are such examples, demonstrating chimeric ultrastructural features of fibroblastic cells in common with smooth muscle cells or with histiocytes, respectively. The presence of epithelioid fibroblastic cells sharing morphologic features with epithelial or plasma cells has not been yet characterized. The authors identified 4 cases of fibrosarcomas (FS) characterized by an unusual phenotype and associated with peculiar ultrastructural findings. The electron microscopic (EM) findings were correlated with the histologic appearance and immunoprofile. All tumors were located in the extremities, 3 in soft tissues and 1 in the bone. By light microscopy 2 cases were composed predominantly by round uniform cells with a striking plasmacytoid appearance. One case mimicked carcinoma, composed predominantly by epithelioid cells and scattered giant tumor cells. The fourth case showed a mixture of plasmacytoid-like and epithelioid cells. By IHC, tumor cells were positive for vimentin and in 2 cases also for epithelial membrane antigen. Kappa/lambda light chain and cytokeratins markers were negative. By EM all 4 tumors showed in addition to classic features of fibroblasts, unusual epithelial-type features, such as secretory granules of "neurosecretory-type" (3 cases), rudimentary cell junctions (3 cases), microvilli (2 cases), and lumen-like structures (1 case). One plasmacytoid-type tumor showed finely granular extracellular deposits. The study describe 4 examples of fibrosarcomas with unusual features at the ultrastructural level, which are associated microscopically with a peculiar phenotype, mimicking plasmacytoma or carcinoma. These findings broaden the spectrum of fibroblastic cell variants in neoplasia.

Adult↗

PubMedDate not supplied

Ultrastructural features of apoptosis in human pituitary adenomas.

Although several recent studies deal with various molecular aspects of apoptosis, or programmed cell death, very little information is available on the ultrastructural changes associated with apoptosis in the adenohypophysis and its role in the regulation of pituitary adenoma growth and progression. This paper describes the distinct ultrastructural sequences that develop during the various phases of the apoptotic process. The study is based on the ultrastructural investigation of more than 8,000 surgically removed pituitary biopsies, which were examined by histology and immunocytochemistry for diagnostic purposes. No apoptosis was found in normal adenohypophysis and it is also a rare event in pituitary adenomas. When present, adenomatous adenohypophysial cells exhibit common and characteristic apoptotic changes. The ultrastructural alterations of membraneous organelles associated with apoptosis are similar to those previously reported in other tissues. It is noteworthy that apoptosis is clearly distinguishable from the ubiquitous dark cells denoting the common way of cell death. The findings suggest that apoptosis in pituitary adenomas is not a random event. Practically every specimen containing multiple apoptotic cells represents corticotroph adenoma. Occasional examples occur in lactotroph or gonadotroph adenomas. Although electron microscopic specimens are admittedly small, the large number of investigated cases gives credence to the observations.

Adenoma↗

PubMedDate not supplied

Ultrastructural alterations of primary human liver sinusoidal cells in patients treated for peritonitis.

Acute peritonitis is still associated with a high mortality rate. Bacterial toxins are rapidly cleared from the peritoneal cavity and may induce general sepsis. The hepatic sinusoidal cells are part of the primary defence against these toxins. The object of this study was to examine ultrastructural alterations of human sinusoidal liver cells from patients undergoing surgical treatment for peritonitis. Liver specimens, obtained from five patients treated with programmed interval peritoneal lavages for peritonitis, were analyzed by electron microscopy. Despite interindividual differences in etiology of peritonitis, the detected ultrastructural alterations displayed a high degree of similarity. Kupffer cells displayed enhanced phagocytotic activity. Numerous Kupffer cell-lymphocyte contacts were observed. Notably, the morphological appearance of the endothelial cells resembled that of an activated phagocytotic cell. The ultrastructural alterations peaked on day 7, and regressed during the course of treatment. Our findings demonstrate that major changes occur in the ultrastructural appearance of both Kupffer cells and sinusoidal endothelial cells in patients with acute peritonitis treated successfully with programmed interval peritoneal lavages. Our data suggest that in peritonitis, a septic spread of toxins and antigens may be modulated by sinusoidal liver cells.

Acute Disease↗

PubMed2001

Characterization of ultrastructural and metabolic abnormalities in semen from men with spinal cord injury.

BACKGROUND: In men with spinal cord injury (SCI), fertility is impaired because of a combination of ejaculatory dysfunction and poor semen quality. We hypothesized that ultrastructural and metabolic abnormalities of sperm could be an underlying factor in infertility in these men. METHODS: To investigate mechanisms contributing to the abnormal sperm parameters, we analyzed seminal constituents and sperm ultrastructure in ejaculates from 7 men with SCI and compared them with 5 control subjects. Sperm adenosine triphosphate (ATP) content was measured using a firefly luciferase bioluminescent assay kit, and ultrastructure was evaluated by electron microscopy. Seminal oxidative stress (8-iso-prostaglandin F-2alpha [8-iso-PGF2alpha]) and transforming growth factor-beta1 (TGF-beta1) levels were measured by specific enzyme-linked immunoabsorbent assay kits. RESULTS: Semen samples from men with SCI showed azoospermia (3) and severe asthenospermia (2; motility 0-5%). A majority (65%) of sperm from asthenospermic samples showed degenerative changes and significant axonemal defects. Incubation of normal sperm with SCI seminal plasma induced a concentration-dependent decrease in sperm motility (43%) accompanied by a significant drop in intracellular ATP content (33%). Semen samples from men with SCI exhibited levels of 8-iso-PGF2alpha 3.5-fold higher than those from controls and levels of TGF-beta1 that were 10% higher than those from controls. CONCLUSION: Our results suggest that seminal constituents of men with SCI are detrimental to sperm movement and that ultrastructural degenerative changes may contribute to the impaired sperm motility and viability seen in these patients. These preliminary results must be confirmed in larger patient populations and longitudinal studies.

Adult↗