Blood transfusion increases radical promoting non-transferrin bound iron in preterm infants

BACKGROUND

Blood transfusion has been recognised as a risk factor for the development of retinopathy of prematurity (ROP) or chronic lung disease (CLD) in preterm infants, but the precise mechanism involved is not understood.

AIM

To investigate the level of non-transferrin bound "free" iron, which has the potential to promote the generation of reactive oxygen species, and its redox status in the plasma of preterm infants immediately before and after blood transfusion.

METHODS

Twenty one preterm infants with a median gestational age and birth weight of 27 weeks and 1021 g respectively were prospectively enrolled in the study. Sixteen of the 21 infants developed ROP and/or CLD. The infants were transfused with concentrated red blood cells at a median age of 32 days. The plasma concentration of total bleomycin detectable iron (BDI) was measured and also the ferrous iron (Fe(2+)) activity by bleomycin-iron complex dependent degradation of DNA.

RESULTS

Even before blood transfusion, BDI was detectable in one third of the blood samples, and all but one sample had ferrous iron activity. After transfusion, both BDI and ferrous iron activity were significantly increased, in contrast with the situation in full term infants. Plasma ascorbic acid (AA) concentration was significantly decreased after blood transfusion, whereas the level of its oxidation product, dehydroascorbic acid (DHAA), and the DHAA/AA ratio were significantly increased compared with before the transfusion. The activity of plasma ferroxidase, which converts iron from the ferrous to the ferric state, was appreciably decreased in preterm infants, as expected from their very low plasma caeruloplasmin concentration.

CONCLUSIONS

Plasma non-transferrin bound iron was significantly increased in preterm infants after blood transfusion and existed partly in the ferrous form, because of the low ferroxidase activity and the reduction of ferric iron (Fe(3+)) by ascorbic acid. This finding was specific to preterm infants and was not observed in full term infants after blood transfusion. Non-transferrin bound "free" iron may catalyse the generation of reactive oxygen species, which may be responsible for the clinical association of blood transfusion with ROP and CLD.

The incidence of apoptotic bodies in membrana granulosa can predict prognosis of ova from patients participating in in vitro fertilization programs

OBJECTIVE

To investigate the relationship between the incidence of apoptotic bodies in membrana granulosa and follicular steroid concentrations in human follicles.

DESIGN

Case-controlled prospective study for 132 individual follicles.

SETTING

Procedures were performed in Yamagata University Hospital.

PATIENT(S)

Thirty-six normo-ovulatory women with tubal infertility underwent ovulation induction for IVF-ET with a conventional hyperstimulation method.

INTERVENTION(S)

Patients underwent follicle aspiration after the administration of hCG.

MAIN OUTCOME MEASURE(S)

The nuclei of recovered granulosa cells were examined by fluorescence microscopy, and the incidence of apoptotic bodies was tabulated. Intrafollicular steroids were evaluated mainly by RIA. These data were analyzed with respect to oocyte-retrieval, oocyte maturity, fertilization, and embryo quality.

RESULT(S)

Membrana granulosa cells in the follicles from which oocytes were subsequently fertilized showed a significantly lower incidence of apoptotic bodies than those in follicles from which the oocytes did not fertilize. Membrana granulosa cells in the follicles from which oocytes were developed into good quality showed a significantly lower incidence of apoptotic bodies than those in the follicles from which oocytes developed into fair and poor quality. The incidence of apoptotic bodies was significantly higher in the mural granulosa cell region than in the cumulus cell region in most cases. Intrafollicular E2, P, and free T levels were not different between the oocyte groups.

CONCLUSION(S)

These results indicate that lower incidence of apoptotic bodies in individual follicles is associated with better outcomes for oocytes. Also, mural granulosa cells and cumulus cell in each follicle may show differentiation during follicular maturation.

Incidence of apoptotic bodies in membrana granulosa of the patients participating in an in vitro fertilization program

OBJECTIVE

To investigate the incidence of apoptotic bodies in mural granulosa cell masses and cumulus cell masses.

DESIGN

Nonrandomized, prospective study.

SETTING

Department of Obstetrics and Gynecology, Yamagata University School of Medicine, Yamagata, Japan.

PATIENT(S)

One hundred twenty-nine normally ovulating women underwent ovulation induction for IVF-ET with GnRH analogue (GnRH-a) and gonadotropins.

INTERVENTION(S)

Patients underwent follicle aspiration after the administration of hCG.

MAIN OUTCOME MEASURE(S)

The nuclei of recovered granulosa cells were examined by fluorescence microscopy and the incidence of apoptotic bodies was tabulated.

RESULT(S)

The incidence of apoptotic bodies was significantly higher in mural granulosa cell masses than in cumulus cell masses in the entire group of 129 patients. Both incidence of apoptotic bodies of mural granulosa cell masses and cumulus cell masses were significantly higher in patients with less than six follicular oocytes compared with patients with six or more oocytes. Nonpregnant patients showed significantly higher incidence of apoptotic bodies in mural granulosa cell masses compared with pregnant patients.

CONCLUSION(S)

These results indicate that mural granulosa cell masses and cumulus cell masses may have different functions in follicular maturation. The incidence of apoptotic bodies in mural granulosa cell masses can be used as an indicator of success of IVF.

Moderate and severe endometriosis is associated with alterations in the cell cycle of granulosa cells in patients undergoing in vitro fertilization and embryo transfer

OBJECTIVE

To determine whether folliculogenesis is impaired in patients with endometriosis.

DESIGN

Prospective study.

SETTING

Yamagata University School of Medicine, Yamagata, Japan.

PATIENT(S)

Thirty women participating in an IVF program.

INTERVENTION(S)

The patients were divided into four groups according to the cause of their infertility: tubal factor (T), n = 7; male factor (M), n = 7; idiopathic (I), n = 7; and endometriosis (E), n = 9. Granulosa cells were obtained from the follicular fluid of each patient and analyzed by flow cytometry.

MAIN OUTCOME MEASURE(S)

The percentage of granulosa cells in each cell-cycle stage.

RESULT(S)

The mean (+/- SD) rate of apoptosis in the granulosa cells obtained from the patients with endometriosis was the highest among the four groups (T = 11.7% +/- 3.3%; M = 5.6% +/- 3.8%; I = 9.6% +/- 5.1%; and E = 18.6% +/- 9.6%). The percentage of S-phase granulosa cells was significantly higher in the patients with endometriosis than in all the other patients combined (E = 12.5% +/- 6%; T + M + I = 9.3% +/- 2.9%). The percentage of G2/M-phase granulosa cells was significantly lower in the endometriosis group than in the other three groups combined (E = 2.3% +/- 2.5%; T + M + I = 4.6% +/- 2.1%).

CONCLUSION(S)

Endometriosis impairs the cell cycle in granulosa cells. This phenomenon may have a detrimental effect on folliculogenesis.

Development of hepatic sinusoidal structure with special reference to the Ito cells

To elucidate sinusoidal cell structure and function under normal conditions and their behavior in diseased settings, an understanding of their developmental aspects is needed. At day 10 of gestation in mice and rats or at 5 weeks of gestation in humans, the hepatic cords grow into the mesenchymal tissue of the septum transversum, and the primitive sinusoidlike structure is simultaneously observed between the liver cell cords. In the margin of the growing liver primordium, mesenchymal cells in the septum transversum are trapped in the subendothelial space. These subendothelial cells are at the early stages of organogenesis and become progenitors of the Ito cells. By days 12-14 of gestation in mice and rats or 8 weeks of gestation in humans, the basic structure of the sinusoids has developed. Embryonic hepatic sinusoids are usually lined by a continuous endothelium without basement membranes, and an incompletely fenestrated sinusoid appears at the middle gestational stage. In the late gestational stages, the Ito cells exhibit myofibroblastlike features in humans, mice, and rats. In association with this event, perisinusoidal reticular networks are gradually intensified. After birth until days 4-5 in mice and rats, the sinusoidal and perisinusoidal structures are almost completely formed, although slight morphological differences from those in adult livers still exist. What happens to sinusoidal endothelial cells and Ito cells in hepatic fibrosis-cirrhosis of the adult may be a deviated or uncontrolled occurrence of what goes on during the fetal period, i.e., a continuous nonfenestrated sinusoidal lining in the early embryonic stage and a myofibroblastlike transformation of Ito cells in late fetal life.

Aging-related changes in calcium oscillations in fertilized mouse oocytes

Aging of oocytes, being not fertilized after ovulation for a prolonged time, considerably affects normal development of the fertilized oocyte. We examined effects of the aging on a series of highly repetitive Ca2+ transients commonly seen in fertilized mouse oocytes (Ca2+ oscillations). Frequency of Ca2+ oscillations in the aged oocyte [20 hrs after induction of superovulation by i.p. human chorionic gonadotropin (hCG)] was significantly higher (34.1 +/- 5.8 l/hr) than the fresh oocyte (14 hr post-hCG, 21.8 +/- 7.9 l/hr). Rates of rise and fall of individual Ca2+ transient in the aged oocyte were significantly slower than the fresh oocyte, whereas durations of individual Ca2+ transients were similar. When extracellular Ca2+ was raised from 2.04 mM to 5.00 mM, aged oocytes showed significant prolongation of the duration of individual Ca2+ transient, that resulted in a sustained elevation of intracellular Ca2+ ([Ca2+]i) in 33% of the aged oocyte. Transient increase in [Ca2+]i by photolysis of a caged Ca2+, Nitr-5, injected into cytoplasm was completely restored in the fresh oocyte [fluorescence intensity of [Ca2+]i indicator dye Fluo-3 (F480) returned to 97 +/- 2% of the control level, time constant = 37 +/- 9 sec]. In contrast, in the aged oocyte, restoration of F480 following Nitr-5 photolysis was incomplete (115 +/- 12% of the control) and slow (time constant = 64 +/- 23 sec). Because inhibition of the Ca2+ pump of the endoplasmic reticulum (ER) by 5 microM thapsigargin almost completely inhibited restoration of F480 following Nitr-5 photolysis in the fresh oocyte, we conclude that the aging-related changes in Ca2+ oscillations may be accounted for by dysfunction of intracellular Ca2+ regulation, presumably of the Ca2+ pump of the ER.

Neonatal hyperbilirubinemia and a common mutation of the bilirubin uridine diphosphate-glucuronosyltransferase gene in Japanese

Neonatal hyperbilirubinemia, which is prevalent among Asian peoples, has been considered as a physiological phenomenon, and its metabolic basis has not been clearly explained. Gilbert syndrome is a common inherited disease of unconjugated hyperbilirubinemia due to decreased bilirubin uridine diphosphate-glucuronosyltransferase (B-UGT), and its role in neonatal jaundice has recently been considered. We have previously reported that the Gly71Arg mutation of the B-UGT gene associated with Gilbert syndrome is prevalent in Japanese, Korean, and Chinese populations and was more frequently detected in neonates with severe hyperbilirubinemia than in control subjects. We have studied 159 Japanese full-term neonates, evaluating the relationship between the B-UGT genotype and the severity of jaundice, as assessed with a transcutaneous bilirubinometer. The gene frequency of the Gly71Arg mutation in these neonates was 0.19, and neonates carrying the Gly71Arg mutation had significantly increased bilirubin levels on days 2-4, manifested in a gene dose-dependent manner. The frequency of the Gly71Arg mutation was 0.47 in the neonates who required phototherapy (i.e., those with more severe hyperbilirubinemia), significantly higher than 0.16 in the neonates who did not require the therapy. The gene frequency of the TA repeat promoter polymorphism, the (TA)7 mutation, was 0.07, and neonates carrying this mutation did not have an increase in bilirubin. These results suggested that the Gly71Arg mutation contributes to the high incidence of neonatal hyperbilirubinemia in Japanese.

Role of the extracellular Ca2+ on the intracellular Ca2+ changes in fertilized and activated mouse oocytes

Changes in intracellular calcium concentration ([Ca2+]i) in fertilized mouse oocytes were measured using the calcium-sensitive dye, fura-2. After fertilization, an initial long-lasting [Ca2+]i increase was followed by a periodic [Ca2+]i increase. The periodic increase in [Ca2+]i persisted for 1 to 3 h and all fertilized oocytes extruded the second polar body within 4 h. The mean interval of periodic [Ca2+]i increase was 470 +/- 180 s (mean +/- SD). The frequency of the periodic [Ca2+]i increase depended on the extracellular calcium concentration. Verapamil and nifedipine inhibited the periodic [Ca2+]i increase. Sixty-five per cent of tested cells extruded the second polar body within 90 min of exposure to 7% ethanol. In these activated oocytes, the long-lasting [Ca2+]i increase was observed. However, no cells showed a repetitive increase in [Ca2+]i. Both release of calcium from intracellular stores and influx of extracellular calcium contribute to the increase in [Ca2+]i induced by ethanol. We conclude that the extrusion of the second polar body requires an increase in [Ca2+]i above a certain threshold level and the mobilization of calcium of both the intracellular and extracellular space in mouse oocytes.

Differential expression of CD34 in normal colorectal tissue, peritumoral inflammatory tissue, and tumour stroma

AIMS

To investigate the role of CD34 positive stromal cells, namely dendritic interstitial cells, in the desmoplastic stroma formation of malignant epithelial neoplasms the distribution of CD34 positive stromal cells was examined in human colorectal adenocarcinomas, peritumoral inflammatory tissue, and normal tissue.

METHODS

Forty one surgically resected human colorectal adenocarcinomas and their corresponding peritumoral inflammatory and normal tissues were examined. To distinguish CD34 positive stromal cells from vascular endothelial cells, immunostaining for both CD34 and CD31 was performed. The distribution of myofibroblasts was also analysed immunohistochemically, and double staining with CD34 and alpha smooth muscle actin (ASMA) was performed.

RESULTS

Most of the stromal cells in the normal colorectal submucosa, muscularis propria, subserosa, and perirectal tissue were positive for CD34. In contrast, the peritumoral inflammatory tissue and the tumour stroma had no CD34 positive stromal cells. The distribution of myofibroblasts was almost the same as in the aforementioned series. No stromal cells double positive for CD34 and ASMA were detected in the peritumoral inflammatory tissues.

CONCLUSIONS

Most stromal fibroblasts are CD34 positive stromal cells (dendritic interstitial cells). In colorectal adenocarcinomas, a lack of CD34 expression in stromal cells is associated with desmoplastic reaction.

Radioimmunoassay of serum medroxyprogesterone acetate (Provera) in women following oral and intravaginal administration

A radioimmunoassay (RIA) method for measuring medroxyprogesterone acetate (MPA, Provera) in serum has been developed utilizing benzene:iso-octane extraction, 3H-MPA to assess procedural losses, goat anti-MPA-3-(0-carboxymethyl) oxime-bovine serum albumin serum and dextran-coated charcoal separation. Control serum blanks were undetectable, 200 pg/ml of MPA was measurable with a high reliability, and intra- and interassay coefficients of variation were 6 and 13 percent, respectively. MPA added to control serum was quantitatively recovered. Serum MPA levels measured in 2 women after ingestion of 10 mg MPA rose to 3.4 to 4.4 ng/ml within 1 to 4 hours after oral intake and fell rapidly thereafter to 0.3 to 0.6 ng/ml within 24 hours. Insertion of Silastic intra-vaginal rings (IVRs), containing 100 or 200 mg of MPA, into 4 women for periods of 3 weeks resulted in a rapid rise of serum MPA after insertion, rather stable MPA levels of 0.9 to 1.6 ng/ml while the IVRs were in place, and a rapid decline of serum MPA following IVR removal. Serum estradiol-17beta and progesterone concentrations, measured about 3 times a week in these patients, indicated that ovulation was consistently inhibited. The serum MPA levels observed in this study were approximately 5 times lower than those reported by other investigators using a double-antibody RIA of MPA in unextracted serum.

Development of glucose utilization studied in single oocytes and preimplantation embryos from mice

Superovulated mouse oocytes and embryos were isolated and incubated with nontracer concentrations of 2-deoxyglucose, an analog of glucose, which is transported into the cells by glucose transporter and phosphorylated by hexokinase to 2-deoxyglucose 6-phosphate; it is not rapidly metabolized further, and accumulates in the cytosol. Using our non-radiometric and enzymatic microassay method, we determined 2-deoxyglucose and 2-deoxyglucose 6-phosphate amounts in individual oocytes and preimplantation embryos after the incubation. Hexokinase activity increased continuously and exponentially during development from follicular oocytes to blastocysts. Endogenous glucose and glucose 6-phosphate decreased precipitously from follicular oocytes to unfertilized and ovulated oocytes. Fertilization induced rapid increases in glucose and glucose 6-phosphate concentrations, which increased exponentially thereafter during embryonic development. 2-Deoxyglucose incorporation and 2-deoxyglucose 6-phosphate formation were undetectable in unfertilized oocytes. However, when cumulus-oocyte complexes were incubated with 2-deoxyglucose, 2-deoxyglucose was incorporated into cumulus cells surrounding follicular oocytes and transported via the gap junctions into the follicular oocytes. Fertilization triggered facilitative 2-deoxyglucose transport in one-cell embryos, and the capacities of 2-deoxyglucose incorporation and 2-deoxyglucose 6-phosphate formation developed along with the maturation of preimplantation embryos.

Raised concentrations of aldehyde lipid peroxidation products in premature infants with chronic lung disease

AIM

To indicate the extent of lipid peroxidation induced by oxidative stress, by measuring aldehyde end products in biological samples.

METHODS

A highly specific gas chromatography and mass spectrometry (GC/MS) method was used to measure plasma concentrations of aliphatic aldehydes within the first week of life in 13 premature infants who subsequently developed chronic lung disease (CLD) and 11 infants without CLD (non-CLD). The oxime-tert-butyldimethylsilyl derivatives of aldehydes were analysed using 2,2,6,6-d4-cyclohexanone as the internal standard.

RESULTS

All of the aldehydes measured were raised in those infants with CLD compared with non-CLD infants. Plasma concentrations of heptanal, 2-nonenal, and 4-hydroxynonenal (HNE) were significantly increased in CLD infants on the day of birth, while the differences in all aldehydes between the two groups were not significant at 4-6 days of age. Logistic regression analysis showed that the increase in these three aldehydes within the first 24 hours of life independently showed significant associations with the development of CLD. In particular, an HNE concentration of > or = 200 nM on day 0 was the best predictor for the early detection of CLD (odds ratio = 32.0), followed by a 2-nonenal concentration of > or = 150 nM (odds ratio = 16.0).

CONCLUSIONS

These findings suggest that lipid peroxidation may have a role in the pathogenesis of neonatal CLD.

Effects of gonadotropin-releasing hormone agonist on the incidence of apoptosis in porcine and human granulosa cells

Gonadotropin-releasing hormone (GnRH) has been found to be expressed in ovaries of various species and to modulate cell differentiation in ovarian cells. GnRH agonists (GnRHa) are widely used in the stimulation protocols of assisted reproduction. In the present study, the direct effects of a GnRHa on the incidence of apoptosis and sterodogenesis in porcine in human granulosa cells were investigated. Cells were obtained from 6-month-old swine and in vitro fertilization patients, and cultured in minimum essential medium (MEM) supplemented with 5% fetal bovine serum for 24 h. The GnRHa (burserelin acetate) was added to the MEM at various concentrations (0, 5, 50, 500 pg/ml, and 5 ng/ml). The nuclei of granulosa cells were examined by fluorescence microscopy after Hoechst 33258 staining, and the incidence of apoptotic cells was tabulated. The GnRHa directly increased the incidence of apoptosis in both types of granulosa cells. The concentration of GnRHa in clinical use is much higher than the concentration which produced apoptosis in granulosa cells here. The clinical dosage of GnRHa should be reconsidered with regard to its apoptosis-inducing effect.

Aberrant expression of the p53 tumor suppressor gene in adult T-cell leukemia and HTLV-I-infected cells

By immunoprecipitation analysis, enhanced p53 expression was detected in 3 of 4 adult T-cell leukemia (ATL) cell lines, 1 of 3 HTLV-I-infected cell lines and 1 of 5 fresh ATL samples, compared with phytohemagglutinin-stimulated peripheral blood lymphocytes. Among these 5 high expressers, p53 missense mutations were indicated in 2 ATL cell lines and 1 fresh ATL sample by extensive p53 cDNA and genomic DNA polymerase chain reaction single-strand conformation polymorphism analysis. No mutation was found throughout the entire coding region of the remaining 2 high expressers (1 ATL and 1 HTLV-I-infected cell lines) and low expressers of p53 (2 HTLV-I-infected cell lines). Tax oncoprotein expression was found in these 2 high p53 expressers in which p53 mutation was not present, but not in low p53 expressers or cells carrying this mutation. The levels of p53 mRNA were similar among the samples regardless of p53 levels. Posttranscriptional mechanisms other than missense mutation would thus appear to increase p53 in the Tax-expressing cells but not in cells containing undetectable levels of Tax. No complex formation between p53 and Tax was observed.

Decreased natural killer cell activity in women with endometriosis

Natural killer (NK) cell activity is characterized by the spontaneous capacity of lymphoid cells derived from nonimmunized hosts to recognize and lyse certain tumor cell lines, virus-infected cells and transplanted tumor cell lines. Endometriosis is characterized by implantation and proliferation of autologous ectopic tissue in the pelvic cavity. Therefore, we focused on examining NK cell activity in women with endometriosis. NK cell activity in peripheral blood from women with endometriosis was lower than in women without endometriosis. On the basis of this finding, we analyzed also the effect of peripheral sera of women with endometriosis on NK cell activity. In the presence of peripheral sera of women with endometriosis, NK cell activity was significantly suppressed as compared with the sera of women without endometriosis. The suppressive effect of sera of women with endometriosis on NK cell activity showed dose-dependent curves. These studies provide the speculation that natural immunity mediated by NK cells may modulate the development of endometrial implants.

Ovarian fecundity in patients with endometriosis can be estimated by the incidence of apoptotic bodies

OBJECTIVE

To investigate the incidence of apoptotic bodies in membrana granulosa in patients with endometriosis.

DESIGN

Retrospective analysis.

SETTING

Yamagata University Hospital.

PATIENT(S)

Fifty-eight normoovulatory women with endometriosis and 45 patients with male factor infertility underwent ovulation induction for IVF-ET with GnRH analogues and gonadotropins.

INTERVENTION(S)

Patients underwent follicle aspiration after the administration of hCG.

MAIN OUTCOME MEASURE(S)

Recovered granulosa cells (GCs) were examined by fluorescence microscopy, and the incidence of apoptotic bodies was tabulated. These data and the other parameters associated with IVF results were analyzed on the basis of both the revised American Fertility Society (AFS) classification of endometriosis and the existence of chocolate cysts.

RESULT(S)

The incidence of apoptotic bodies in membrana granulosa of patients with endometriosis was significantly higher than that of the control (male factor infertility) group and increased as the stage of the revised AFS classification advanced. The incidence of apoptotic bodies in membrana granulosa was significantly higher in patients with chocolate cysts than in those without chocolate cysts. The patients with endometriosis had smaller numbers of developed follicles (> or = 15 mm), harvested oocytes, and mature oocytes than the male factor infertility patients. The existence of chocolate cysts corresponded with a reduced number of both harvested oocytes and mature oocytes.

CONCLUSION(S)

Through the apoptosis of GCs, the existence of endometriosis may have negatively affected the follicle development and oocyte quality.

An immunohistochemical study of developing glomeruli in human fetal kidneys

BACKGROUND

In the glomerulonephritis, mesenchymal cells frequently repeat the expression of fetal immunohistochemical phenotypes. However, in human glomerulogenesis the phenotypic alteration of mesangial and other types of glomerular cells has not been clearly defined. Our aim was to clarify the characteristics of fetal mesangial cells and glomerular capillary endothelial cells, as well as their changes during glomerulogenesis using immunohistochemistry.

METHODS

We examined the renal tissues of 34 autopsied fetuses and neonates, 5 children, and 5 adults using immunohistochemistry and immunoelectron microscopy, using antibodies for cytoskeletons, contraction-associated proteins, and endothelial cell markers.

RESULTS

In the V and S stages, there were no cells showing mesangial and endothelial features within the vesicles and the S-shaped bodies. In the S stage, small blood vessels, consisting of endothelial cells (CD31+, CD34+) and primitive perivascular mesenchymal cells (alpha-smooth muscle actin+, low molecular caldesmon+, vimentin+), were branched from developing interlobular arteries and appeared to extend to the lower clefts of the S-shaped bodies. In the C stage, the perivascular mesenchymal cells aggregated at the root of the immature glomeruli. In the M stage, they migrated toward the periphery of immature glomeruli and gradually lost their fetal immunohistochemical features. Similarly, with further maturation, the fetal glomerular capillary endothelial cells gradually lost the immunostaining for CD34, while the strong staining intensity of CD31 remained unchanged, just as that in the adult glomerular capillary endothelial cells.

CONCLUSIONS

In human glomerulogenesis, we demonstrate that fetal mesangial and capillary endothelial cells change their immunohistochemical phenotypes with maturation. They gradually lose fetal immunohistochemical phenotypes. Already before birth, the mesangial cells in almost all glomeruli at the late M stage acquire the adult phenotype.

Hyaluronic acid inhibits apoptosis in granulosa cells via CD44

PURPOSE

This study was designed to examine whether hyaluronic acid (HA) inhibits apoptosis in cumulus and mural granulosa cells and to examine whether this effect of HA was mediated through CD44.

METHODS

Mural and cumulus granulosa cells were obtained from in vitro fertilization patients. The cells were cultured with various concentrations of HA or HA plus various concentrations of anti-CD44 antibody without serum supplement. After 24 hr of culture, the cells were fixed and stained with Hoechst 33258. One thousand granulosa cells of each conditions were observed by fluorescence microscopy.

RESULTS

HA inhibited apoptosis in both kinds of granulosa cells, and anti-CD44 antibody prevented this effect of HA.

CONCLUSIONS

The incidence of apoptotic granulosa cells with fragmented condensed nuclei was reduced by HA via CD44.

A monoclonal antibody reacting with the zona pellucida of the oviductal egg but not with that of the ovarian egg of the golden hamster

A monoclonal antibody (mAb) designated AZPO-8 was produced by hybridizing a mouse myeloma with spleen cells from BALB/c mice immunized with materials obtained from the hamster oviduct. With an immunofluorescence test, AZPO-8 reacted with the zona pellucida (ZP) of ovulated eggs in the oviduct (ZP-OVI) but not with the zona pellucida of eggs in the ovary (ZP-OVA). Using indirect enzyme immunostaining, this mAb reacted with epithelial cells of the oviduct, the uterus (especially the cervical epithelium) and the gastric mucosa, but not with other hamster tissues examined. The reactivity of antigen-positive tissues was abrogated by pretreatment of the tissues with periodic acid. Western blotting analysis revealed that AZPO-8 reacted with substances of broad molecular weight range, and the strongest reactivity was detected at a molecular weight of approximately 200,000 in both cases when extract of ZP-OVI or the hamster oviduct was applied on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gel. AZPO-8 showed strong hemagglutination activity only to group A human red blood cells. These results indicated that (1) ZP-OVI had an antigen that was not detected on ZP-OVA, (2) ZP-OVI and the oviduct shared the same antigenicity, and (3) the antigenic determinant reactive with the mAb might be carbohydrate in nature. A possible role of this antigen in fertilization was discussed.

Effects of aging on inositol 1,4,5-triphosphate-induced Ca(2+) release in unfertilized mouse oocytes

We previously demonstrated in the mouse oocyte that in vivo postovulatory aging significantly suppresses activity of the endoplasmic reticulum (ER) Ca(2+)-ATPase (Igarashi et al. 1997. Mol Reprod Dev 48:383-390). We undertook the present study to further examine the effects of oocyte aging on Ca(2+) release from the inositol 1,4,5-triphosphate (InsP(3))-sensitive Ca(2+) channels of the ER membrane, because not only Ca(2+) reuptake, but also Ca(2+) release from the ER, substantially affect Ca(2+) oscillations in fertilized oocytes. A transient increase in cytosolic free Ca(2+) concentration ([Ca(2+)](i)) was induced by photolysis of caged InsP(3) microinjected into the cytoplasm in both fresh (14 hr post hCG) and aged (20 hr or 24 hr post hCG) oocytes, where the maximum rate of increase in [Ca(2+)](i) significantly decreased in the aged oocytes. Reduced ER Ca(2+) release in the aged oocyte may not be attributable to aging-related desensitization of the InsP(3)-sensitive Ca(2+) channels in the ER because concentrations of caged InsP(3) for half maximal [Ca(2+)](i) increase were identical for fresh and aged oocytes. The peak [Ca(2+)](i) response following administration of 5 microM thapsigargin, a specific ER Ca(2+)-ATPase inhibitor, was significantly reduced in the aged oocyte, suggesting reduction of the ER Ca(2+) stores. We conclude from these results that reduction of Ca(2+) release from the InsP(3)-sensitive Ca(2+) stores in the aged oocyte arises from depletion of the ER Ca(2+) stores with aging. These aging-related changes in Ca(2+) release and reuptake may account for alterations in Ca(2+) oscillations in aged fertilized oocytes.