OBJECTIVETo explore the apoptosis and the express of proliferating cell nuclear antigen (PCNA) in spermatogenic cells, and study generation function of the rabbit after scrotal reconstruction with flaps.

METHODSThe 48 New Zealand white rabbits were randomly divided into three groups as experimental group (the scrotum reconstructed with flaps, n = 48), the control group (the sham operated group, n = 24) and the blank group (n = 18). The apoptosis and the expression of PCNA in the spermatogenic cells were detected with TUNEL and the immunohistochemistry from the 3rd to the 8th week after operation. 8 weeks later, 12 animals in each group were fed respectively with one female rabbit to observe the procreation.

RESULTSThe apoptotic index of the spermatogenic cells in blank group was 7.73 +/- 4.95. 3 weeks after operation, the apoptotic index of spermatogenic cells was 22.59 +/- 3.04 in the experimental group, and 21.13 +/- 1.68 in control group, showing no significant difference between the two groups (P > 0.05). 8 weeks after operation, the apoptotic index of spermatogenic cells was 71.85 +/- 2.69 in the experimental group, and 13.64 +/- 2.09 in control group, show a significant difference between them (P < 0.05). The apoptotic index in experimental group increased gradually from the 3rd to 8th week after scrotal reconstruction , which was markedly higher than that in the blank group (P < 0.05). The apoptotic index in control group was higher than that in the blank group at the 3rd week (P < 0.05), but not at the 8th week (P > 0.05). The proliferation index of spermatogenic cells was 9.32 +/- 9.30 and 12.52 +/- 3.87 in experimental group at the 3rd and 4th week, respectively, which was significantly lower than that in blank group (43.07 +/- 2.25) and control group (45.69 +/- 4.98) at the 3rd week (P < 0.05). The proliferation index of spermatogenic cells was 46.98 +/- 18.92 and 49.53 +/- 9.79 in experimental group at the 7th and 8th week, respectively, 39.90 +/- 5.10 in control group at the 8th week, showing no difference between the two groups (P > 0.05). The proliferation index of spermatogenic cells in control group at the 3rd and 8th week was not different from that in the blank group (P > 0.05). The female pairing rabbits in the blank and control group were all pregnant, and the average childbirths were 6.0 +/- 1.28 and 5.92 +/- 1.31 respectively, with no difference between the two groups (P > 0.05). All the female pairing rabbits in the experimental group were not pregnant, showing a significant difference from those in the blank and control group (P < 0.05).

CONCLUSIONSThe rabbit generation functional disturbance after scrotal reconstruction with flaps is due to the excessive apoptosis of spermatogenic cell. The spermatogenic cell proliferation is affected only in the early postoperative period, but can recover later.

Animals ; Apoptosis ; Cell Proliferation ; Male ; Proliferating Cell Nuclear Antigen ; metabolism ; Rabbits ; Scrotum ; surgery ; Seminiferous Epithelium ; cytology ; Skin Transplantation ; Surgical Flaps

OBJECTIVETo explore the changes of rat testicular spermatogenic epithelium stimulated by bacterial lipopolysaccharide (LPS) in vivo.

METHODSTwenty Wistar rats were divided into two groups: control group and experimental group. The control group was treated with pyrogen-free saline (1 ml/kg) and the experimental group was injected ip with saline containing LPS (1 mg/kg) once every two days. Two groups were operated after ten days in order to investigate the testicular pathological changes by HE staining and the expression of proliferating cell nuclear antigen( PCNA), alpha-catenin in spermatogenic epithelium by immunohistochemistry assay.

RESULTSThe testes of the experimental group showed inflammatory changes. The positive expression of PCNA in seminiferous epithelium was significantly lower than that of control group. The number of positive cells in every seminiferous, in which only spermatogonia were stained in experimental group were 59 +/- 5 and it showed significant decrease compared with the control (P < 0.01). Furthermore, the percentage of such seminiferous tubules was 0.673 +/- 0.054 and increased apparently (P < 0.01). The expression of alpha-catenin in testicular tissue of the experimental group declined (P < 0.01), and cellular positive granular light density was 0.150 +/- 0.014.

CONCLUSIONThe ability of spermatogonium proliferation and the function of conglutination of cells under inflammatory condition of the testes declined, which may be one of the etiologies of male infertility.

Animals ; Bacterial Toxins ; Disease Models, Animal ; Male ; Orchitis ; metabolism ; pathology ; Proliferating Cell Nuclear Antigen ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Seminiferous Epithelium ; metabolism ; alpha Catenin ; metabolism

OBJECTIVETo investigate the impact of experimental varicocele (EV) on the ipsilateral testis in rats.

METHODSEV was induced by partial ligation of the left renal vein in male SD rats, the control rats subjected to sham operation, and the testes of the EV models and controls were extirpated 6, 12, and 18 weeks later. Johnson's score, ultrastructure of seminiferous tubules, intratesticular testosterone concentration (ITC) and germ cell apoptotic index (AI) of each left testis were evaluated.

RESULTSJohnson's scores were (6.92 +/- 0.52), (4.83 +/- 0.41) and (2.95 +/- 0.26), ITCswere (6.32 +/- 0.85), (5.17 +/- 0.76) and (4.11 +/- 0.69) and AIs were (5.32 +/- 1.23), (15.21 +/- 0.97) and (21.13 +/- 1.12) respectively in the 6 w , 12 w and 18 w EV groups, significantly lower than in the corresponding control groups, (9.56 +/- 0.35, 9.63 +/- 0.31, 9.39 +/- 0.46), (9.64 +/- 1.23, 9.38 +/- 0.69, 9.73 +/- 0.49) and (3.21 +/- 1.15, 3.43 +/- 1.21, 3.61 +/- 1. 15) (P < 0.05), the former two showing a gradual decline while the latter a significant elevation with the increasing duration of varicocele. The damage to the ultrastructure of seminiferous tubules was aggravated with the prolonging of varicocele.

CONCLUSIONEV can cause a progressive decline of ITC, dyszoospermia and increased AI of germ cells.

Animals ; Apoptosis ; Disease Models, Animal ; Infertility, Male ; Male ; Rats ; Rats, Sprague-Dawley ; Seminiferous Epithelium ; cytology ; ultrastructure ; Testis ; chemistry ; metabolism ; Testosterone ; metabolism ; Varicocele ; metabolism ; physiopathology

OBJECTIVETo explore the effects of different methods of scrotal reconstruction on the apoptosis of spermatogenic cells and expression of the bcl-2 protein in patients with third-degree scrotal burns.

METHODSForty male and 24 female 2-month-old Guizhou mini-pigs were used in this study, the former equally randomized to groups I (normal control), II (natural healing), III (skin grafting) and IV (skin flap grafting). Ten months after the establishment of the model of third-degree burns, 6 male pigs from each group were paired with the female pigs and fed for 3 weeks. Then the female pigs were fed for another 4 months, followed by observation of their reproductivity. At 12 months, the bilateral testes were taken from the male pigs for detection of the apoptosis index of spermatogenic cells by TUNEL and determination of the expression of the bcl-2 protein by immunohistochemistry. The data obtained were subjected to single factor analysis of variance.

RESULTSThe apoptosis indexes of spermatogenic cells were (7.07 +/- 3.5), (40.34 +/- 4.85), (15.14 +/- 1.36) and (39.29 +/- 5.73)% in groups I , II, III and IV, respectively, significantly higher in groups II , III and IV than in I (P<0.05), with statistically significant differences between group III and groups II and IV (P<0.05) but not between II and IV (P>0.05). The expression rates of the bcl-2 protein were (75.07 +/- 3.74), (54.93 +/- 4.03), (66.85 +/- 3.06) and (53.33 +/- 5.22)% in groups I, II, III, and IV, respectively, remarkably higher in I than in the other three (P<0.05), with significant differences between group III and groups II and IV (P<0.05) but not between II and IV (P>0.05). Pregnancies were found in all the female pigs of group I with 10.0 +/- 1.18 newborns and in 4 of group III with 9.92 +/- 1.31 newborns, but in none of groups II and IV, with significant differences between group I and the other three (P<0.05) as well as between group III and groups II and IV (P<0.05), but not between II and IV (P>0.05).

CONCLUSIONAll the three methods of reconstruction for the scrotum with third-degree burns can suppress spermatogenic function, increase the apoptosis of spermatogenic cells and decrease the expression of the bcl-2 protein, among which, skin grafting least affects spermatogenic function.

Animals ; Apoptosis ; Burns ; surgery ; Disease Models, Animal ; Female ; Male ; Reconstructive Surgical Procedures ; methods ; Scrotum ; injuries ; metabolism ; surgery ; Seminiferous Epithelium ; cytology ; metabolism ; Skin Transplantation ; methods ; Spermatogenesis ; Swine ; Swine, Miniature

AIMTo evaluate the effect of a protein synthesis inhibitor cycloheximide on arresting activity in spermatogenesis and sperm count in male rats.

METHODSThe study used seminiferous tubule (ST) segments from adult rats cultured in vitro with or without cycloheximide to condition culture media, which have been concentrated, size fractioned (30-50 kDa) and administered 7 days to adult rats by intraperitoneal injections. The effects on testicular and epididymal weights, spermatogenesis and epididymal sperm count were determined.

RESULTSThe fraction (30-50 kDa), named arresting, obtained from the culture without cycloheximide decreased testicular and epididymal weights (P<0.01) and reduced the epididymal sperm count significantly. Study of the spermatogenic cycle by transillumination showed spermatogenic arrest at stage VII in rats treated with arresting compared to that observed in controls. The length of stage VII in the group receiving the seminiferous tubules culture media with cycloheximide (30-50 KDa CHX-STCM fraction) was similar to control.

CONCLUSIONThe difference in the effect may be the result of the presence or absence of arresting, a protein secreted by the tubules.

Animals ; Arrestin ; biosynthesis ; Culture Media, Conditioned ; Cycloheximide ; pharmacology ; Epididymis ; cytology ; drug effects ; growth & development ; Male ; Protein Synthesis Inhibitors ; pharmacology ; Rats ; Seminiferous Epithelium ; cytology ; drug effects ; physiology ; Seminiferous Tubules ; metabolism ; Sperm Count ; Testis ; drug effects ; growth & development

During spermatogenesis, developing germ cells that lack the cellular ultrastructures of filopodia and lamellipodia generally found in migrating cells, such as macrophages and fibroblasts, rely on Sertoli cells to support their transport across the seminiferous epithelium. These include the transport of preleptotene spermatocytes across the blood-testis barrier (BTB), but also the transport of germ cells, in particular developing haploid spermatids, across the seminiferous epithelium, that is to and away from the tubule lumen, depending on the stages of the epithelial cycle. On the other hand, cell junctions at the Sertoli cell-cell and Sertoli-germ cell interface also undergo rapid remodeling, involving disassembly and reassembly of cell junctions, which, in turn, are supported by actin- and microtubule-based cytoskeletal remodeling. Interestingly, the underlying mechanism(s) and the involving biomolecule(s) that regulate or support cytoskeletal remodeling remain largely unknown. Herein, we used an in vitro model of primary Sertoli cell cultures that mimicked the Sertoli BTB in vivo overexpressed with the ribosomal protein S6 (rpS6, the downstream signaling protein of mammalian target of rapamycin complex 1 [mTORC1]) cloned into the mammalian expression vector pCI-neo, namely, quadruple phosphomimetic and constitutively active mutant of rpS6 (pCI-neo/p-rpS6-MT) versus pCI-neo/rpS6-WT (wild-type) and empty vector (pCI-neo/Ctrl) for studies. These findings provide compelling evidence that the mTORC1/rpS6 signal pathway exerted its effects to promote Sertoli cell BTB remodeling. This was mediated through changes in the organization of actin- and microtubule-based cytoskeletons, involving changes in the distribution and/or spatial expression of actin- and microtubule-regulatory proteins.
Actins/metabolism* ; Animals ; Blood-Testis Barrier/metabolism* ; Cells, Cultured ; Male ; Mechanistic Target of Rapamycin Complex 1/metabolism* ; Permeability ; Rats ; Ribosomal Protein S6/metabolism* ; Seminiferous Epithelium/metabolism* ; Sertoli Cells/metabolism* ; Signal Transduction/physiology*

AIMTo investigate the changes in the extracellular matrix protein expression and the morphology of seminiferous tubules in the testis of 88 azoospermic men.

METHODSThe patients were of the following categories: (1) 22 cases of Sertoli-cell-only syndrome, (2) 20 cases of spermatogenic arrest, and (3) 46 cases with hypospermatogenesis. Testicular sections were immunohistochemically stained for fibronectin, vimentin, laminin and collagen type IV. The seminiferous tubular diameter and the connective matrix zone (CMZ, the acellular zone between the basement membrane [BM] and the peritubular cells) thickness were measured. Seminiferous tubules were typed according to the thickness of the connective matrix in the lamina propria. The predominant tubule type and the Johnsen and Silber scores were determined.

RESULTSThe mean tubular diameter were 119 +/- 27, 117 +/- 20, and 140 +/- 38 microm for Groups 1, 2, and 3, respectively. Both the laminin and the type IV collagen were localized to the epithelial BM and peritubular cells. In most of the tubules, BM and peritubular cells were separated by a homogenous acellular layer, the CMZ, in which laminin, type IV collagen, fibronectin and vimentin were not present. It is perceived that the worse the testicular histology, the higher the thickness of the CMZ.

CONCLUSIONIn testis with no or low sperm production, the diameter of the seminiferous tubules is decreased, the thickness of the seminiferous tubular wall is increased and a CMZ is formed between the peritubular cells and the BM. The thickness of CMZ is increasing with the advancement of testiclar deterioration. The most important morphologic predictive factor for spermiogenesis is the predominant

Adult ; Collagen Type IV ; analysis ; biosynthesis ; Extracellular Matrix Proteins ; analysis ; biosynthesis ; Fibronectins ; analysis ; biosynthesis ; Humans ; Immunohistochemistry ; Laminin ; analysis ; biosynthesis ; Logistic Models ; Male ; Middle Aged ; Oligospermia ; metabolism ; pathology ; Seminiferous Epithelium ; metabolism ; pathology ; Spermatogenesis ; Testis ; chemistry ; metabolism ; pathology ; Vimentin ; analysis ; biosynthesis

AIMTo understand the biological functions of the ectoplasmic specializations between Sertoli cells and maturing spermatids in seminiferous epithelia.

METHODSIn order to disrupt the function of the ectoplasmic specializations, nectin-2, which is expressed at the specialization, was neutralized with anti-nectin-2 antibody micro-injected into the lumen of the mouse seminiferous tubule. Anti-nectin-3 antibody was also micro-injected into the lumen in order to neutralize nectin-3, which is expressed at the specialization.

RESULTSThe actin filaments at the specialization disappeared, and exfoliation of maturing spermatids was observed by electron microscopy.

CONCLUSIONNectin-2 was neutralized by anti-nectin-2 antibody and nectin-3 was neutralized by anti-nectin-3 antibody, respectively. Inactivated nectin-2 and nectin-3 disrupted the nectin-afadin-actin system, and finally the actin filaments disappeared. As a result, the specialization lost the holding function and detachment of spermatids was observed. One of the functions of the specialization seems to be to hold maturing spermatids until spermiation.

Actins ; metabolism ; Animals ; Antibodies ; immunology ; pharmacology ; Cell Adhesion Molecules ; immunology ; metabolism ; Cell Communication ; drug effects ; physiology ; Intercellular Junctions ; drug effects ; metabolism ; Male ; Mice ; Mice, Inbred ICR ; Microfilament Proteins ; metabolism ; Microscopy, Confocal ; Nectins ; Seminiferous Epithelium ; cytology ; drug effects ; metabolism ; Sertoli Cells ; cytology ; drug effects ; metabolism ; Spermatids ; cytology ; drug effects ; metabolism

AIMTo investigate the stage-specific localization of transforming growth factor (TGF) beta1 and beta3 during spermatogenesis in adult human testis.

METHODSThe localization of TGFbeta1 and beta3 was investigated by immunohistochemical staining method employing specific polyclonal antibodies.

RESULTSBoth TGFbeta1 and beta3 and their receptors were preponderant in the Leydig cells. TGFbeta1 could not be detected in the seminiferous tubules. TGFbeta3 and TGFbeta-Receptor (R) I were mainly seen in the elongated spermatids, while TGFbeta-RII in the pachytene spermatocytes and weak in the spermatogonia, spermatids and Sertoli cells. Only TGFbeta-RII was detected in the Sertoli cells. TGFbeta3, TGFbeta-RI and TGFbeta-RII showed a staining pattern dependent upon the stages of the seminiferous epithelium cycle.

CONCLUSIONTGFbeta isoforms and their receptors are present in the somatic and germ cells of the adult human testis, suggesting their involvement in the regulation of spermatogenesis.

Adult ; Humans ; Immunohistochemistry ; Leydig Cells ; metabolism ; Ligands ; Male ; Middle Aged ; Orchiectomy ; Prostatic Neoplasms ; pathology ; Receptors, Transforming Growth Factor beta ; metabolism ; Seminiferous Epithelium ; cytology ; metabolism ; Spermatids ; metabolism ; Spermatogenesis ; physiology ; Testis ; metabolism ; physiology ; Transforming Growth Factor beta ; metabolism ; Transforming Growth Factor beta1 ; Transforming Growth Factor beta3

AIMTo study the expression pattern of the retinoic acid metabolizing enzymes RALDH2 and CYP26b1 during mouse postnatal testis development at both mRNA and protein levels.

METHODSReal-time polymerase chain reaction and Western blot analysis were performed to determine the relative quantity of RALDH2 and CYP26b1 at both mRNA and protein levels at postnatal day 1, 5, 10, 20, and in adult mice (70 days testes). Testicular localization of RALDH2 and CYP26b1 during mouse postnatal development was examined using immunohistochemistry assay.

RESULTSAldh1a2 transcripts and its protein RALDH2 began to increase at postnatal day 10, and remained at a high level through postnatal day 20 to adulthood. Cyp26b1 transcripts and CYP26b1 protein did not change significantly during mouse postnatal testis development. RALDH2 was undetectable in the postnatal 1, 5 and 10 day testes using immunohistochemistry assay. At postnatal day 20 it was detected in pachytene spermatocytes. Robust expression of RALDH2 was restricted in round spermatids in the adult mouse testis. In the developing and adult testis, CYP26b1 protein was confined to the peritubular myoepithelial cells.

CONCLUSIONOur results indicate that following birth, the level of retinoic acid in the seminiferous tubules might begin to increase at postnatal day 10, and maintain a high level through postnatal day 20 to adulthood.

Aldehyde Oxidoreductases ; genetics ; metabolism ; Animals ; Cytochrome P-450 Enzyme System ; genetics ; metabolism ; Gene Expression Regulation, Developmental ; Male ; Mice ; Mice, Inbred BALB C ; RNA, Messenger ; metabolism ; Rabbits ; Retinoic Acid 4-Hydroxylase ; Seminiferous Epithelium ; cytology ; metabolism ; Sensitivity and Specificity ; Spermatids ; cytology ; metabolism ; Testis ; cytology ; growth & development ; metabolism