The role of MIR-186 and ZNF545 in inhibiting the proliferation of multiple myeloma cells

This study aimed to investigate the mechanism underlying the inhibitory effect of tumor suppressor gene miR-186 and zinc finger protein 545 (ZNF545) on the proliferation of multiple myeloma (MM) cells. CD138 magnetic beads were used to isolate different types of myeloma cell lines (KM3, U266, RPMI-8226, and H929), which were then infected by lentivirus carrying the miR-186 gene. Using uninfected myeloma cells as the control, MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, Thiazolyl Blue Tetrazolium Bromide] assay was performed to calculate the rate of cell proliferation at different time points. In addition, the correlation between the expression of Jagged 1 and miR-186 was analyzed by real-time Polymerase Chain Reaction (PCR). Furthermore, the effect of 5-Aza-2-deoxycytidine and acetylase inhibitor Trichomycin A (TSA) on the expression of ZNF545 and proliferation/apoptosis of MM cells was investigated using Reverse Transcription-Polymerase Chain Reaction (RT-PCR), Western blotting (WB), MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] cell proliferation assay, and Annexin V-FITC/PI staining. Compared with the control group, the proliferation of miR-186-overexpressing U266 and RPMI-8226 cells was significantly decreased. In cell cloning experiments, miR-186 decreased the number of U266 and RPMI-8226 clones while reducing the protein expression of Jagged 1. The expression level of ZNF545 in myeloma patients was also reduced to some extent. ZNF545 protein also promoted the apoptosis of myeloma cells. By inhibiting the proliferation of myeloma cells, miR-186 gene and ZNF protein may be used as tumor suppressors in the treatment of myeloma.

The beneficial effects of cumulus cells and oocyte-cumulus cell gap junctions depends on oocyte maturation and fertilization methods in mice

Cumulus cells are a group of closely associated granulosa cells that surround and nourish oocytes. Previous studies have shown that cumulus cells contribute to oocyte maturation and fertilization through gap junction communication. However, it is not known how this gap junction signaling affects in vivo versus in vitro maturation of oocytes, and their subsequent fertilization and embryonic development following insemination. Therefore, in our study, we performed mouse oocyte maturation and insemination using in vivo- or in vitro-matured oocyte-cumulus complexes (OCCs, which retain gap junctions between the cumulus cells and the oocytes), in vitro-matured, denuded oocytes co-cultured with cumulus cells (DCs, which lack gap junctions between the cumulus cells and the oocytes), and in vitro-matured, denuded oocytes without cumulus cells (DOs). Using these models, we were able to analyze the effects of gap junction signaling on oocyte maturation, fertilization, and early embryo development. We found that gap junctions were necessary for both in vivo and in vitro oocyte maturation. In addition, for oocytes matured in vivo, the presence of cumulus cells during insemination improved fertilization and blastocyst formation, and this improvement was strengthened by gap junctions. Moreover, for oocytes matured in vitro, the presence of cumulus cells during insemination improved fertilization, but not blastocyst formation, and this improvement was independent of gap junctions. Our results demonstrate, for the first time, that the beneficial effect of gap junction signaling from cumulus cells depends on oocyte maturation and fertilization methods.

Assessment of mouse germinal vesicle stage oocyte quality by evaluating the cumulus layer, zona pellucida, and perivitelline space

To improve the outcome of assisted reproductive technology (ART) for patients with ovulation problems, it is necessary to retrieve and select germinal vesicle (GV) stage oocytes with high developmental potential. Oocytes with high developmental potential are characterized by their ability to undergo proper maturation, fertilization, and embryo development. In this study, we analyzed morphological traits of GV stage mouse oocytes, including cumulus cell layer thickness, zona pellucida thickness, and perivitelline space width. Then, we assessed the corresponding developmental potential of each of these oocytes and found that it varies across the range measured for each morphological trait. Furthermore, by manipulating these morphological traits invitro, we were able to determine the influence of morphological variation on oocyte developmental potential. Manually altering the thickness of the cumulus layer showed strong effects on the fertilization and embryo development potentials of oocytes, whereas manipulation of zona pellucida thickness effected the oocyte maturation potential. Our results provide a systematic detailed method for selecting GV stage oocytes based on a morphological assessment approach that would benefit for several downstream ART applications.

Casein kinase 1 alpha regulates chromosome congression and separation during mouse oocyte meiotic maturation and early embryo development

Casein kinase I alpha (CK1α) is a member of serine/threonine protein kinase, generally present in all eukaryotes. In mammals, CK1α regulates the transition from interphase to metaphase in mitosis. However, little is known about its role in meiosis. Here we examined Ck1α mRNA and protein expression, as well as its subcellular localization in mouse oocytes from germinal vesicle to the late 1-cell stage. Our results showed that the expression level of CK1α was increased in metaphase. Immunostaining results showed that CK1α colocalized with condensed chromosomes during oocyte meiotic maturation and early embryo development. We used the loss-of-function approach by employing CK1α specific morpholino injection to block the function of CK1α. This functional blocking leads to failure of polar body 1 (PB1) extrusion, chromosome misalignment and MII plate incrassation. We further found that D4476, a specific and efficient CK1 inhibitor, decreased the rate of PB1 extrusion. Moreover, D4476 resulted in giant polar body extrusion, oocyte pro-MI arrest, chromosome congression failure and impairment of embryo developmental potential. In addition, we employed pyrvinium pamoate (PP), an allosteric activator of CK1α, to enhance CK1α activity in oocytes. Supplementation of PP induced oocyte meiotic maturation failure, severe congression abnormalities and misalignment of chromosomes. Taken together, our study for the first time demonstrates that CK1α is required for chromosome alignment and segregation during oocyte meiotic maturation and early embryo development.

Biochemical and anatomical evidence for specialized voltage-dependent calcium channel gamma isoform expression in the epileptic and ataxic mouse, stargazer

Inherited forms of ataxia and absence seizures in mice have been linked to defects in voltage-dependent calcium channel subunits. However, a correlation between the sites of neuronal dysfunction and the impact of the primary lesion upon calcium channel subunit expression or function has not been clearly established. For example, the mutation in stargazer mice has pleiotropic consequences including synaptic alterations in cerebellar granule cells, hippocampal CA3/mossy fibers, and cortical neurons in layer V that, presumably, lead to ataxia and seizures. Genetic analysis of stargazer mice determined that the defective gene encodes a protein expressed in brain (gamma2) with limited homology to the skeletal muscle L-type calcium channel gamma1 subunit. Although additional gamma isoforms have been subsequently identified primarily in neural tissue, little was known about the proteins they encode. Therefore, this study explored the distribution and biochemical properties of gamma2 and other gamma isoforms in wild-type and stargazer brain. We cloned human gamma2, gamma3, and gamma4 isoforms, produced specific anti-peptide antibodies to gamma isoforms and characterized both heterologously expressed and endogenous gamma. We identified regional specificity in the expression of gamma isoforms by western analysis and immunohistochemistry. We report for the first time that the mutation in the stargazer gene resulted in the loss of gamma2 protein. Furthermore, no compensatory changes in the expression of gamma3 or gamma4 protein were evident in stargazer brain. In contrast to other voltage-dependent calcium channel subunits, gamma immunostaining was striking in that it was primarily detected in regions highly enriched in excitatory glutamatergic synapses and faintly detected in cell bodies, suggesting a role for gamma in synaptic functions. Sites of known synaptic dysfunction in stargazer (the hippocampal CA3 region, dentate gyrus, and cerebellar molecular layer) were revealed as relying primarily upon gamma2, as total gamma isoform expression was dramatically decreased in these regions. Electron microscopy localized anti-gamma antibody immunostaining to dendritic structures of hippocampal mossy fiber synapses, with enrichment at postsynaptic densities. To assess the association of native gamma with voltage-dependent calcium channel or alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor subunits, gamma isoforms (gamma2, gamma3 and gamma4) were detergent solubilized from mouse forebrain. Antibodies against a highly conserved C-terminal epitope present in gamma2, gamma3 and gamma4 immunoprecipitated voltage-dependent calcium channel subunits (alpha1B), providing the first in vivo evidence that gamma and voltage-dependent calcium channels form stable complexes. Furthermore, both anti-gamma2 antibodies and anti-alpha1B antibodies independently immunoprecipitated the AMPA receptor subunit, GluR1, from mouse forebrain homogenates. In summary, loss of gamma2 immunoreactivity in stargazer is precisely localized so as to contribute to previously characterized synaptic defects. The data in this paper provide compelling evidence that gamma isoforms form complexes in vivo with voltage-dependent calcium channels as well as AMPA receptors, are selectively and differentially expressed in neuronal processes, and localize primarily to dendritic structures in the hippocampal mossy fiber region.

Correlation between decrease of 11beta-hydroxysteroid dehydrogenase activity and hypokalemia induced by furosemide in rats

AIM

To investigate the correlation between decrease of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) activity and hypokalemia induced by furosemide (Fur) in rats.

METHODS

SD rats were given single dose or successive doses of Fur by gavage. The activity of 11beta-HSD was evaluated by measuring the ratio of 11-dehydrocorticosterone (A) and corticosterone (B) in urine and conversion rate of B to A in renal cortex microsome preparation was determined with HPLC.

RESULTS

After giving single dose of Fur (40, 100, and 250 mg/kg) or multiple doses of Fur (10, 20, and 100 mg/kg, bid x 20 d), the ratio of A/B was reduced by 29.0 %, 58.6 %, and 60.9 % at 0 - 2 h; 14.4 %, 36.0 %, and 44.9 %, respectively; the conversion rate of B to A was decreased by 29 %, 33 %, and 37 %; 6 %, 17 %, and 23 %, respectively. The serum potassium was significantly reduced by multiple doses of Fur (20 and 100 mg/kg, bid x 20 d) (P < 0.01). The reduction in serum potassium was positively correlated with the lowering of A/B ratio and the conversion of B to A (P < 0.01).

CONCLUSION

The inhibition of renal 11beta-HSD activity may be another new biochemical mechanism for hypokalemia induced by Fur.

Pharmacokinetics of sustained-release capsule of 5-isosorbide mononitrate in 20 healthy Chinese young men

AIM

To compare the pharmacokinetics of domestic and imported sustained-release capsule of 5-isosorbide mononitrate (5-IM).

METHODS

A single and 5-d-repeated oral doses of 5-IM 50 mg were performed on 2 groups of 20 Chinese healthy subjects (10 subjects for each group) in a randomized crossover protocol. The 5-IM in plasma were measured by gas chromatography with electron-captured detector method. Data were analyzed automatically by using a CAPP program on a PC computer.

RESULTS

Fitting the 5-IM concentration-time curves to one-compartment model or following trapezoidal rule, the parameters such as Tmax, Cmax, Ke, MRT, and AUC were calculated and there were no significant differences between the two kinds of capsule. The major pharmacokinetic parameters of domestic and imported 5-IM sustained-release capsule with a 5-d multiple dose were respectively: Cmax (677 +/- 103) and (702 +/- 76) micrograms.L-1; Tmax (5.1 +/- 2.0) and (5.6 +/- 1.3) h; MRT (11.5 +/- 0.5) and (11.4 +/- 0.7) h; AUC0-infinity (12,121 +/- 1346) and (12,352 +/- 988) micrograms.h.L-1. The fraction of drug absorbed in vivo was correlated well with the percentage amount of drug released in vitro at corresponding time (P < 0.05), and the fluctuation indices on d 5 in multiple dose study were not significantly different between the two formulations (P > 0.05). The relative bioavailability of the domestic capsule for single and multiple dose were 96% +/- 11% and 98% +/- 10%, respectively.

CONCLUSION

Domestic 5-IM sustained-release capsule showed bioequivalence compared with the imported capsule and provided the same nitrate-low interval in the latter part of the 24-h dosing interval.

Stereoselective metabolism of metoprolol in isolated rat liver

AIM

To study the stereoselective pharmacokinetics of the enantiomers of metoprolol (Met).

METHODS

The enantiomers of Met were metabolized in isolated rat liver with hemoglubin-free medium. The enantiomers of Met were analyzed with HPLC.

RESULTS

The linear kinetics were found in 3 doses (0.16, 0.32, and 0.64 mg) of R-(+)- and S-(-)-Met. The time-concentration curve of Met was fitted in first order-kinetics compartment model. There were differences in the pharmacokinetic parameters (K, T1/2, and Cl) between the enantiomers at the same dose (P < 0.01). The ratio of liver clearence of S-(-)-Met/R-(+)-Met was 0.14-0.17.

CONCLUSION

Pharmacokinetics of enantiomers of Met in the isolated rat liver were stereoselective, with a preferential clearance of R-(+)-Met, which elimination was not a saturable process.

Pharmacokinetic-pharmacodynamic modeling of metoprolol stereoisomers in spontaneously hypertensive rat

AIM

To study the combined pharmacokinetic-pharmacodynamic (PK-PD) model of metoprolol stereoisomers, and compare their inhibitory effects on cardiovascular system in the spontaneously hypertensive rats (SHR).

METHODS

The drug concentration in plasma was measured by the reversed phase HPLC and the drug effects were recorded by polygraph. The pharmacokinetic parameters and the PK-PD model parameters were calculated.

RESULTS

The plasma concentration-time profiles were adequately described by two-compartment model. Differences of Vd between (+)-Met and (-)-Met were found. The relationships between effects and concentration of effect compartment were represented by the sigmoid-Emax model. The Css50 of Vmax, dp/dtmax, and HR inhibitory effects of (+)-Met were larger than those of (-)-Met.

CONCLUSION

Stereo-selective drug distribution and different potencies of the inhibitory effects of (+)-Met and (-)-Met existed in SHR.

Pharmacokinetics of bendazac lysine in 10 Chinese young men

AIM

To compare the pharmacokinetics of domestic and imported tablets of bendazao lysine (BL).

METHODS

A single oral dose of 500 mg BL of this 2 kinds of tablets was given to 10 Chinese volunteers of Han nationality in a randomized crossover study. Plasma levels were determined with HPLC-UV method. Data were analyzed automatically by using a CAPP program on microcomputer.

RESULTS

The plasma concentration-time curve was fitted to 2-compartment open model, and the major pharmacokinetic parameters of domestic and imported BL tablets were shown respectively as following: Cmax 66 +/- 16 and 65 +/- 8 mg.L-1; Tmax 0.98 +/- 0.22 and 0.98 +/- 0.21 h; T1/2 beta 6.2 +/- 1.8 and 6.2 +/- 1.7 h; AUC 335 +/- 47 and 337 +/- 58 mg.h.L-1. There was no significant difference between domestic and imported tablets. The bioavailability of the domestic vs that of the imported tablet was 99 +/- 12%. The unchanged BL in urine were about 5.4% and 5.6% respectively of the dosage in 24 h after a single oral dose.

CONCLUSION

The two kinds of tablets had the same biological effects.

Enhancement by the complement membrane attack complex of tumor necrosis factor-alpha-induced endothelial cell expression of E-selectin and ICAM-1

Although TNF-alpha and several products of the activated complement system (e.g., C3b, iC3b, and C5a) are known to modulate endothelial cell function in vitro, relatively little is known about the potential modulatory role of the membrane attack complex (MAC) in endothelial cell activation. Using an in vitro neutrophil-endothelial adhesion assay and a quantitative whole cell ELISA to measure endothelial E-selectin and intracellular adhesion molecule-1 (ICAM-1) expression, we examined the modulatory role of the MAC in TNF-alpha-induced neutrophil-endothelial cell adhesive interactions. Activation of quiescent human umbilical vein endothelial cells (HUVECs) with TNF-alpha results in a concentration-dependent increase in neutrophil adhesion measured at 4 h. Assembly of sublytic concentrations of the MAC on endothelial cells did not result in changes in neutrophil-HUVEC adhesion measured at 4 h. Activation of HUVECs with TNF-alpha followed by assembly of the MAC resulted in a marked increase in neutrophil binding as compared with that observed in cells treated with TNF-alpha alone. Blocking studies of mAb revealed that in either TNF-alpha-stimulated or TNF-alpha and MAC-activated endothelial cells enhanced neutrophil binding was nearly entirely attributable to E-selectin and ICAM-1. This conclusion was further supported by a whole-cell ELISA, which provided evidence that the MAC augments TNF-alpha-induced up-regulation of both E-selectin and ICAM-1. This study provides data that support the conclusion that the distal complement system (MAC) can enhance TNF-alpha-induced proinflammatory endothelial cell functions.

Enhancement by the complement membrane attack complex of tumor necrosis factor-alpha-induced endothelial cell expression of E-selectin and ICAM-1

Although TNF-alpha and several products of the activated complement system (e.g., C3b, iC3b, and C5a) are known to modulate endothelial cell function in vitro, relatively little is known about the potential modulatory role of the membrane attack complex (MAC) in endothelial cell activation. Using an in vitro neutrophil-endothelial adhesion assay and a quantitative whole cell ELISA to measure endothelial E-selectin and intracellular adhesion molecule-1 (ICAM-1) expression, we examined the modulatory role of the MAC in TNF-alpha-induced neutrophil-endothelial cell adhesive interactions. Activation of quiescent human umbilical vein endothelial cells (HUVECs) with TNF-alpha results in a concentration-dependent increase in neutrophil adhesion measured at 4 h. Assembly of sublytic concentrations of the MAC on endothelial cells did not result in changes in neutrophil-HUVEC adhesion measured at 4 h. Activation of HUVECs with TNF-alpha followed by assembly of the MAC resulted in a marked increase in neutrophil binding as compared with that observed in cells treated with TNF-alpha alone. Blocking studies of mAb revealed that in either TNF-alpha-stimulated or TNF-alpha and MAC-activated endothelial cells enhanced neutrophil binding was nearly entirely attributable to E-selectin and ICAM-1. This conclusion was further supported by a whole-cell ELISA, which provided evidence that the MAC augments TNF-alpha-induced up-regulation of both E-selectin and ICAM-1. This study provides data that support the conclusion that the distal complement system (MAC) can enhance TNF-alpha-induced proinflammatory endothelial cell functions.

Flow dependence of metoprolol elimination in isolated perfused rat liver

The effect of blood flow rates on hepatic elimination of metoprolol (Met) was studied in a recirculating isolated perfused rat liver system with a constant infusion of Met into the reservoir. This design ensures that, at a steady state, the elimination rate of Met is a constant. The results showed that at flow rates of 10, 20, and 30 ml.min-1, the concentrations of Met entering the liver (Cin) were 7.6, 5.0, and 3.4 micrograms.ml-1 and the concentrations leaving the liver (Cout) were 1.2, 2.0, and 2.7 micrograms.ml-1, while the logarithmic average concentrations in hepatocytes (C) were 3.4, 3.2, and 3.0 micrograms.ml-1, respectively. It is concluded that the hepatic elimination of Met is flow-dependent, which is in accordance with the 'parallel tube' model.

Effect of dose of metoprolol on its elimination by isolated perfused rat liver in vitro

The effects of dose of metoprolol (Met) on hepatic elimination was studied in isolated rat liver perfused at a flow of 25 ml.min-1. The results showed that Met was eliminated by rat liver in accordance with one-compartment model. Linear kinetic eliminating processes (apparent first-order kinetics) were found in doses of Met 0.2, 0.5, 1.0, and 2.0 mg, T1/2 were 8.3, 8.8, 9.6, and 10.6 min and the clearance rate were 11.7, 11.8, 9.6, and 8.6 ml.min-1, respectively. Nonlinear eliminating processes were found in doses of Met 4, 8, and 12 mg. Vm and Km were 0.98, 1.05, and 0.94 microgram/min-1.ml-1 and 15.6, 16.9, and 14.6 micrograms.ml-1, respectively. It is concluded that hepatic Met elimination is independent on lower doses, but rested upon high doses.

Clinical reactivation of herpes simplex virus type 2 infection in seropositive pregnant women with no history of genital herpes

OBJECTIVE

To determine the risk for genital herpes and asymptomatic herpes simplex virus (HSV) shedding in late pregnancy and delivery in a population of HSV type 2 (HSV-2)-seropositive but previously asymptomatic pregnant women.

DESIGN

A prospective inception cohort study.

PARTICIPANTS

A total of 1355 pregnant women with no history of genital herpes referred from three private obstetrics practices between November 1985 and June 1988.

MAIN OUTCOME MEASURES

Confidential questionnaires evaluated sexual risk factors in relation to HSV-2 serologic status as determined by Western blot analysis. Herpes simplex virus shedding was determined by viral culture of the cervix and vulva and of any suspicious lesions.

RESULTS

Antibody to HSV-2 was detected in 439 of 1355 pregnant women (32%) with no history of genital herpes. Asymptomatic HSV shedding was detected in 5 of 1160 cultures (0.43%) obtained in late pregnancy and during delivery. A first episode of clinical genital herpes was recognized by 43 of 264 HSV-2-seropositive women (16%) during their pregnancy.

CONCLUSIONS

Serologic evidence of unknown HSV-2 infection was common in pregnant women without a history of genital herpes. Asymptomatic viral shedding in these women occurred at a rate similar to that seen in women with symptomatic genital HSV-2 infection. To improve recognition of genital herpes near term, obstetricians should counsel pregnant women about the high prevalence and mild and diverse symptoms of genital HSV-2 infection.

Analysis of false positive HIV-1 serologic testing in Kenya

Sera of 95 mothers and 129 children from Nairobi, Kenya, collected in 1976, and of 466 adults and 193 children of Embu District, Kenya, collected in 1984 and 1985, were analyzed for the presence of human immunodeficiency virus type 1 (HIV-1) antibodies. Although no HIV-1 seropositivity was demonstrated by western blot analysis in both study groups, 7% of Nairobi mothers and 10% of adult females from Embu District had false positive results by enzyme immunoassay (EIA) compared with less than 1% seroreactivity rates observed in adult males and children. False positive results were not due to simian T lymphotropic virus type III (STLV-IIIAGM)/human T lymphotropic virus type IV (HTLV-IV) seropositivity. Sixty-one percent of the HIV-1 EIA reactive sera could not be explained by cytotoxic activity to lymphocytes bearing the HLA-DR4 or HLA-DQw3 phenotype. We conclude that false positive HIV EIA tests are frequently encountered in East Africa. Seroprevalence rates in rural Africa must be interpreted with caution due to the decreased specificity of HIV EIAs.