ROS-INDUCED OXIDATIVE STRESS IN NOBILE-TYPE DENDROBIUM PROTOCORM-LIKE BODIES (PLBS) DURING VITRIFICATION

BACKGROUND

Oxidative stress involved in cryopreservation protocols may be responsible for the poor survival of tissues after cryopreservation.

OBJECTIVE

In the current study, we aimed to clarify the role of oxidative stress and its relationship with survival rate during cryopreservation of PLBs from nobile-type Dendrobium.

MATERIALS AND METHODS

ROS, antioxidants and oxidative products and the survival rate in PLBs from Dendrobium Hamanal Lake Dream were determined during vitrification.

RESULTS

Relative survival of PLBs decreased significantly after preculture and rewarming (P<0.01). Generation of ·O₂^- and protein carbonyl (PCO) increased significantly after preculture. Dramatic increases in ·O₂^-, H₂O₂ and MDA, and significant decreases in AsA content, activities of SOD and CAT were observed after rewarming.

CONCLUSION

ROS-induced oxidative stress was associated with the poor survival of PLBs following vitrification. ·O₂^- was the predominant ROS resulting in the decreased survival after preculture, while H₂O₂ together with ·O₂^- appear to be responsible for the survival decrease after rewarming.

Preparation of solid lipid nanoparticles loaded with garlic oil and evaluation of their in vitro and in vivo characteristics

OBJECTIVE

Solid lipid nanoparticles (SLN) are colloidal drug carriers and may be suitable for delivery of garlic oil, a nutraceutical with medicinal properties, whose use has been limited by its poor solubility. We tested whether poor solubility of garlic oil would be overcome by complexing with SLN by high-pressure homogenization and ultrasound techniques. The effects of lipid phase, surfactant mixture and loading concentration of garlic oil on particle size and distribution were also investigated.

MATERIALS AND METHODS

High pressure homogenization technique was used to prepare SLN, using orthogonal experiment method to optimize entrapment efficiency, loading efficiency, and recovery of SLN. Pharmacokinetics of garlic oil loaded solid lipid nanoparticles after oral administration to rats was studied by using LC/MS/MS method.

RESULTS

Mean particle size and zeta potential of SLN were, respectively, 106.5 ± 40.3 nm and -30.2 mv. The majority of SLN had a less ordered arrangement of crystals at room temperature, which was beneficial for increasing the drug loading capacity. Drug entrapment efficiency was > 90 percent and showed a relatively long-term physical stability. It was feasible to prepare a lyophilized product with good long-term stability. When 10% trehalose and 5% sucrose were used as cryopreservants, SNL particle size increased from 106.5 nm prior to lyophilisation to 155.3 nm after reconstitution. The garlic oil content in SLN decreased to about 85% (respectively, 34.3 vs. 39.4 mg/mL prior to lyophilisation) due to volatility of garlic oil. Pharmacokinetic studies in rats demonstrated that distribution and elimination of diallyl trisulfide (DATS) and diallyl disulfide (DADS) in garlic oil were rapid. Additionally, elimination of garlic oil-SLN complex is faster than that of garlic oil alone, probably, due to phagocytosis.

CONCLUSIONS

An SLN complex with garlic oil exhibits characteristics similar to those of parenteral emulsions, even after lyophilization and reconstitution.

Caesarean Scar Pregnancy: Treatment with Bilateral Uterine Artery Chemoembolization Combined with Dilation and Curettage

Objective:

This study investigated bilateral uterine artery chemo -embolization (BUACE) combined with dilation and curettage (D&C) in caesarean scar pregnancy (CSP).

Methods:

Nineteen women with CSP were referred for interventional radiology. In 13 patients, BUACE was performed before D&C, following a diagnosis of CSP. A further six patients received BUACE for massive vaginal bleeding after D&C for inevitable miscarriage; the diagnosis of CSP was subsequently confirmed ultrasonographically. BUACE of the uterine arteries was performed using gelfoam particles following intra-arterial infusion of 100 mg/m2 methotrexate.

Results:

BUACE was technically successful and immediate haemostasis was achieved in all patients. Blood loss was significantly greater during D&C undertaken before BUACE compared with D&C after BUACE, but this bleeding was controlled by BUACE. No patient required further surgical intervention and there were no severe complications. The gestational sac and placenta could no longer be detected ultrasonographically and the menstrual cycle returned to normal 2 - 3 months after treatment in all patients.

Conclusions:

BUACE followed by D&C seems to be a safe and effective treatment for CSP and should be considered as a treatment of choice.

Effects of transcranial direct current stimulation on hemichannel pannexin-1 and neural plasticity in rat model of cerebral infarction

The aim of this study was to investigate the effects of transcranial direct current stimulation (TDCS) on hemichannel pannexin-1 (PX1) in cortical neurons and neural plasticity, and explore the optimal time window of TDCS therapy after stroke. Adult male Sprague-Dawley rats (n=90) were randomly assigned to sham operation, middle cerebral artery occlusion (MCAO), and TDCS groups, and underwent sham operation, unilateral middle cerebral artery (MCA) electrocoagulation, and unilateral MCA electrocoagulation plus TDCS (daily anodal and cathodal 10 Hz, 0.1 mA TDCS for 30 min beginning day 1 after stroke), respectively. Motor function was assessed using the beam walking test (BWT), and density of dendritic spines (DS) and PX1 mRNA expression were compared among groups on days 3, 7, and 14 after stroke. Effects of PX1 blockage on DS in hippocampal neurons after hypoxia-ischemia were observed. TDCS significantly improved motor function on days 7 and 14 after stroke as indicated by reduced BWT scores compared with the MCAO group. The density of DS was decreased after stroke; the TDCS group had increased DS density compared with the MCAO group on days 3, 7, and 14 (all P<0.0001). Cerebral infarction induced increased PX1 mRNA expression on days 3, 7, and 14 (P<0.0001), and the peak PX1 mRNA expression was observed on day 7. TDCS did not decrease the up-regulated PX1 mRNA expression after stroke on day 3, but did reduce the increased post-stroke PX1 mRNA expression on days 7 and 14 (P<0.0001). TDCS increased the DS density after stroke, indicating that it may promote neural plasticity after stroke. TDCS intervention from day 7 to day 14 after stroke demonstrated motor function improvement and can down-regulate the elevated PX1 mRNA expression after stroke.

In vitro and in vivo evaluation of Triptolide-loaded pluronic P105 polymeric micelles

Thin film method was applied successfully to prepare Triptolide (TP)-loaded micelles system. With a dynamic light scattering sizer and a transmission electron microscopy, it was shown that the TP-loaded micelles had a mean size of 84.3±6.4 nm with a spherical shape. The in vitro release profiles indicated that the release of TP from the micelles exhibited a sustained release behavior. A similar phenomenon was also observed in a pharmacokinetic study in rats, in which AUC of the micelles formulation were 4.7-fold higher than that of TP injection. The biodistribution study in rats showed that the TP-loaded micelles not only decreased drug uptake by liver, but also increased distribution of drug in ovary. The present work demonstrated the feasibility of controlled delivery of TP utilizing micelles system.

A simple LC-MS/MS method for determination of magnolol in rat blood and its application in a pharmacokinetic study

A simple LC-MS/MS method was developed for determination and pharmacokinetic study of magnolol in rat blood. Blood sample pretreatment involved a one-step extraction with methanol of 100 µL blood. The chromatographic separation was carried out on a Agilent Zobax SB C18 column with a mobile phase consisting of acetonitrile-0.2% formic acid (55:45, v/v) at a flow rate of 0.3 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring via electro spray ionization source with positive mode. A high throughput was achieved with a run time of 4 min per sample. The standard curve for magnolol was linear (r > 0.999) over the concentration range of 2-1 000 ng/mL, with a lower limit of quantification of 2 ng/mL. The intra- and inter-day precision (relative standard deviation) values were not higher than 12% and the accuracy (relative error) was <5% at three quality control levels. This simple, fast and highly sensitive method was fully validated and successfully applied to a clinical pharmacokinetic study of magnolol in rats after oral administration.

Pro-inflammatory cytokine-stimulated first trimester decidual cells enhance macrophage-induced apoptosis of extravillous trophoblasts

OBJECTIVE

As human blastocyst-derived extravillous trophoblasts (EVTs) invade the early decidua, they are positioned to interact with immune cells and resident decidual cells, and remodel spiral arteries into high capacity vessels that increase blood flow to the developing fetal-placental unit. Shallow EVT invasion elicits incomplete vascular transformation and reduces uteroplacental blood flow that presages adverse pregnancy outcomes. Excess macrophages in the decidua induce EVT apoptosis via tumor necrosis factor-alpha (TNF-α) secretion. Our previous observation that pro-inflammatory cytokines enhance neutrophil and macrophage activator granulocyte-macrophage colony-stimulating factor (GM-CSF) expression in first trimester decidual cells is now extended to include: (1) the specific macrophage activator M-CSF; (2) macrophage activation and subsequent enhancement of EVT apoptosis by both GM-CSF and M-CSF.

STUDY DESIGN

Quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay assessed M-CSF expression in first trimester decidual cells incubated with interleukin-1 beta (IL-1β) or TNF-α. Peripheral monocyte-derived macrophages pre-incubated with conditioned media from decidual cell cultures were co-cultured with a first trimester EVT cell line, HTR-8/SVneo cells. Macrophage activation was examined and EVT apoptosis evaluated by DNA fragmentation, caspase activation and cell membrane asymmetry.

RESULTS

IL-1β or TNF-α significantly enhanced M-CSF expression in first trimester decidual cells. The conditioned media from these cultures activates macrophages, which promote caspase 3/7-dependent EVT apoptosis with antibodies against GM-CSF or M-CSF blocking this effect.

CONCLUSIONS

Pro-inflammatory cytokines increases synthesis of M-CSF in first trimester decidual cells. Both GM-CSF and M-CSF activate macrophages, which initiate caspase-dependent EVT apoptosis.

[Expression of human leucocyte antigen in ectopic endometrial tissue of endometriosis]

OBJECTIVE

To investigate the human leucocyte antigen (HLA) expression of ectopic endometrial epithelial cells in cases with endometriosis and its role in pathogenesis of endometriosis.

METHODS

By immunohistochemical analysis, HLA expression was observed in ectopic endometrial epithelial cells of 25 endometriosis patients. Ectopic endometrial cells were cultured in vitro successfully and the expression of HLA were analyzed by flow cytometry in 10 out of the 25 patients. Eutopic endometrium of 15 normal women were taken as control.

RESULTS

(1) Expression of HLA class I molecule on ectopic endometrial epithelial cells of endometriosis measured by the immunohistochemical analysis was lower than those of controls, (4.0 +/- 0.5) score and (1.2 +/- 0.8) score respectively. So was the expression rate by flow cytometry in vitro culture (63.38 +/- 11.88)% and (5.27 +/- 2.88)% respectively (P < 0.01). (2) The expression of HLA class II molecule on ectopic endometrial epithelial cells of endometriosis was significantly increased. The outcome by immunohistochemical analysis was (0.2 +/- 0.1) score (control group) and (4.1 +/- 0.7) score (case group) and by flow cytometry was (7.19 +/- 2.43)% and (58.57 +/- 14.99)% respectively (P < 0.01).

CONCLUSIONS

The abnormal HLA expression could play a role in the pathogenesis of endometriosis.

BAC contig from a 3-cM region of mouse chromosome 11 surrounding Brca1

Even with the completion of a draft version of the human genome sequence only a fraction of the genes identified from this sequence have known functions. Chromosomal engineering in mouse cells, in concert with gene replacement assays to prove the functional significance of a given genomic region or gene, represents a rapid and productive means for understanding the role of a given set of genes. Both techniques rely heavily on detailed maps of chromosomal regions, initially to understand the scope of the regions being modified and finally to provide the cloned resources necessary to allow both finished sequencing and large insert complementation. This report describes the creation of a BAC clone contig on mouse chromosome 11 in a region showing conservation of synteny with sequences on human chromosome 17. We have created a detailed map of an approximately 3-cM region containing at least 33 genes through the use of multiple BAC mapping strategies, including chromosome walking and multiplex oligonucleotide hybridization and gap filling. The region described is one of the targets of a large effort to create a series of mice with regional deletions on mouse chromosome 11 (33-80 cM) that can subsequently be subjected to further mutagenesis.

Identification of heparin-binding EGF-like growth factor as a target in intercellular regulation of epidermal basal cell growth by suprabasal retinoic acid receptors

The role of retinoic acid receptors (RARs) in intercellular regulation of cell growth was assessed by targeting a dominant-negative RARalpha mutant (dnRARalpha) to differentiated suprabasal cells of mouse epidermis. dnRARalpha lacks transcriptional activation but not DNA-binding and receptor dimerization functions. Analysis of transgenic mice revealed that dnRARalpha dose-dependently impaired induction of basal cell proliferation and epidermal hyperplasia by all-trans RA (tRA). dnRARalpha formed heterodimers with endogenous retinoid X receptor-alpha (RXRalpha) over RA response elements in competition with remaining endogenous RARgamma-RXRalpha heterodimers, and dose-dependently impaired retinoid-dependent gene transcription. To identify genes regulated by retinoid receptors and involved in cell growth control, we analyzed the retinoid effects on expression of the epidermal growth factor (EGF) receptor, EGF, transforming growth factor-alpha, heparin-binding EGF-like growth factor (HB-EGF) and amphiregulin genes. In normal epidermis, tRA rapidly and selectively induced expression of HB-EGF but not the others. This induction occurred exclusively in suprabasal cells. In transgenic epidermis, dnRARalpha dose-dependently inhibited tRA induction of suprabasal HB-EGF and subsequent basal cell hyperproliferation. Together, our observations suggest that retinoid receptor heterodimers located in differentiated suprabasal cells mediate retinoid induction of HB-EGF, which in turn stimulates basal cell growth via intercellular signaling. These events may underlie retinoid action in epidermal regeneration during wound healing.

Keratinocyte-specific retinoid regulation of human cellular retinoic acid binding protein-II (hCRABPII) gene promoter requires an evolutionarily conserved DR1 retinoic acid-responsive element

Transcription of the hCRABPII gene is retinoid inducible in human skin keratinocytes (KC) but, surprisingly, not in cultured cells. The promoter for the gene harbors three putative nuclear receptor binding sites: DR5, upstream of the transcription start site; DR1 (DR1d), distal to the site; and DR1 (DR1p), a proximal variant. DR1d, but not DR1p, is conserved between human and mouse. Although DR5 has been found to be a retinoid receptor target in COS-1 cells, the function of DR1 remains unknown. We examined the functions of these DR in retinoid regulation of the hCRABPII promoter in human KC. In reporter gene assays, no significant retinoid response was observed in the promoter in cultured KC; however, overexpression of retinoid receptor heterodimers RARgamma x RXRalpha restored the response. Gel supershift assays showed that endogenous RARgamma x RXRalpha levels are much lower in cultured KC than in skin in vivo. Ligand-binding assays showed that cultured KC contain only one-third of the level of retinoic acid receptor (RAR) and one-eighth of the level of retinoid X receptor found in KC in skin. Deletion of the DR1d or DR5 sites reduced retinoid-induced promoter activity by 63% and 27%, respectively. Isolated DR1d and DR5 sites, but not DR1p, efficiently bound RARgamma-RXRalpha and conferred RAR-selective retinoid responsiveness on a heterologous promoter. These data indicate that: (i) the previously reported lack of retinoid regulation of endogenous hCRABPII gene transcription in cultured KC is likely due to insufficient levels of RARgamma x RXRalpha, but not their cofactors; (ii) the conserved DR1d site is the major functional target in RARgamma x RXRalpha regulation of hCRABPII in KC; (iii) the DR1p site is nonfunctional due to its lack of affinity for RARgamma x RXRalpha, although its half-sites share high sequence homology with the consensus retinoid receptor-binding half-site.

Suprabasal expression of a dominant-negative RXR alpha mutant in transgenic mouse epidermis impairs regulation of gene transcription and basal keratinocyte proliferation by RAR-selective retinoids

To determine whether 9-cis retinoic acid receptors (RXRs) regulate the biological activity of all-trans retinoic acid (tRA) and its receptors (RARs) in skin, we have targeted a dominant-negative RXR alpha (dnRXR alpha) lacking transactivation function AF-2 to differentiated suprabasal keratinocytes in the epidermis of transgenic mice. Driven by the suprabasal-specific keratin-10 gene promoter, expression of dnRXR alpha severely reduced the ability of RAR-selective ligands tRA and CD367 to induce epidermal mRNA levels of the CRABPII, CRBPI, and CRBPII genes, which contain RA-responsive elements (RAREs) DR1 and/or DR2. It also reduced gene-specific, synergistic induction of CRBPI mRNA by a combination of CD367 and RXR-selective SR11237. Like endogenous RXR alpha, dnRXR alpha in epidermal nuclear extracts from the transgenic mice competitively formed heterodimers with endogenous RAR gamma on RAREs, suggesting that dnRXR alpha impairs retinoid signaling by competing with endogenous RAR gamma-RXR alpha heterodimers. Histologically, the epidermis of dnRXR alpha mice showed no detectable developmental abnormalities. Surprisingly, in adult animals, the suprabasal expression of dnRXR alpha significantly reduced the ability of topically applied tRA to stimulate proliferation of undifferentiated keratinocytes in the basal layer of epidermis. RXR-selective ligands alone had no detectable effects on both normal and transgenic mouse epidermis. Accordingly, we suggest that in vivo: (1) in suprabasal keratinocytes, retinoids regulate gene transcription via RAR-RXR heterodimers in which RAR confers a predominant ligand response, whereas RXR AF-2 is required for liganded RAR AF-2 to efficiently trans-activate target genes, and (2) this suprabasal RXR-assisted mechanism indirectly regulates proliferation of basal keratinocytes likely via intercellular signaling.

[Pathological study on placenta from pregnancies with systemic lupus erythematosus]

Pathological study on the placenta of 18 cases of pregnancy complicated with systemic lupus erythematosus (SLE) and 23 cases of normal pregnancy was done. The average weight and placenta-villi area ratio of the placenta from pregnancy with SLE were significantly lower than those of the normal (P < 0.05). Scanning under electron microscope showed the placental villi of the SLE group slender and branching little, with their ends bean-sprout looking and the surface covered with pin-point holes, even slitted masses. Immunohistologic examination indicated deposition of IgG, IgA, IgM, C3 on the villi capillary wall surface, which suggested damage of the placental function of the SLE gravidae by the immunologic compounds.

[Correlation between outcome of pregnancy and condition of disease at conception in systemic lupus erythematosus women]

Thirty four pregnant patients with systemic lupus erythematosus (SLE) were divided into 3 groups: (1) primigravida, (2) previous history of spontaneous abortion, and (3) previous history of induced abortion. Outcomes of these pregnancies showed that the average birth weight in primigravida group was significantly higher than that in the other 2 groups (P < 0.05). Grouping by clinical status of SLE at conception, there were 4 kinds of situation: (1) remission, (2) controlled, (3) active, and (4) first onset. Patients with SLE of active stage had the lowest birth weight and gestational age babies (P < 0.05). The best time for conception in SLE women was at the time of remission or controlled stage, i.e. patients treated with prednisone in a dose of 5-15 mg/day for more than 6 months or without any medication for at least 1 year.