Morphofunctional State of the Ovaries in Rats with Experimental Model of Functional Cysts and Their Treatment with Gonadotropin-Releasing Hormone Antagonist

The morphofunctional features of the ovaries were evaluated in rats with functional ovarian cysts model treated with gonadotropin-releasing hormone antagonist. Administration of the antagonist significantly (p=0.009) reduced the number of cysts and the growth of follicles in the ovaries. The obtained results attest to a possibility of successful treatment of functional ovarian cysts with gonadotropin-releasing hormone antagonist.

Effect of Gonadotropin-Releasing Hormone Antagonist on the Expression Patterns of Insulin-Like Growth Factor 1, Androgen Receptor, and Luteinizing Hormone Receptor in an Experimental Rat Model of Functional Ovarian Cysts

We studied the expression of insulin-like growth factor 1 (IGF-1), androgen receptor (AR) and luteinizing hormone receptor (LHR) in the ovaries under the conditions of the modeling and subsequent treatment of functional ovarian cysts with gonadotropin-releasing hormone antagonist (ant-GnRH). The intensity of IGF-1, LHR, and AR expression in the generative elements of rat ovaries changed under conditions of functional ovarian cysts simulation, as well as during treatment with ant-GnRH. In both experimental groups, the expression levels of the studied markers in preantral follicles and epithelial lining of cysts were found to be related to the number of growing follicles and cysts. A divergence of LHR and AR expression indices and a more pronounced decrease in the number of cystic cavities were observed in the group receiving ant-GnRH. These changes demonstrate a positive effect of ant-GnRH on intra-ovarian regulatory factors and a therapeutic effect in functional ovarian cysts.

Long-term monitoring of chronic demyelination and remyelination in a rat ischemic stroke model using macromolecular proton fraction mapping

Remyelination is a key process enabling post-stroke brain tissue recovery and plasticity. This study aimed to explore the feasibility of demyelination and remyelination monitoring in experimental stroke from the acute to chronic stage using an emerging myelin imaging biomarker, macromolecular proton fraction (MPF). After stroke induction by transient middle cerebral artery occlusion, rats underwent repeated MRI examinations during 85 days after surgery with histological endpoints for the animal subgroups on the 7th, 21st, 56th, and 85th days. MPF maps revealed two sub-regions within the infarct characterized by distinct temporal profiles exhibiting either a persistent decrease by 30%-40% or a transient decrease followed by return to nearly normal values after one month of observation. Myelin histology confirmed that these sub-regions had nearly similar extent of demyelination in the sub-acute phase and then demonstrated either chronic demyelination or remyelination. The remyelination zones also exhibited active axonal regrowth, reconstitution of compact fiber bundles, and proliferation of neuronal and oligodendroglial precursors. The demyelination zones showed more extensive astrogliosis from the 21st day endpoint. Both sub-regions had substantially depleted neuronal population over all endpoints. These results histologically validate MPF mapping as a novel approach for quantitative assessment of myelin damage and repair in ischemic stroke.

Quantitative assessment of demyelination in ischemic stroke in vivo using macromolecular proton fraction mapping

A recent MRI method, fast macromolecular proton fraction (MPF) mapping, was used to quantify demyelination in the transient middle cerebral artery occlusion (MCAO) rat stroke model. MPF and other quantitative MRI parameters (T₁, T₂, proton density, and apparent diffusion coefficient) were compared with histological and immunohistochemical markers of demyelination (Luxol Fast Blue stain, (LFB)), neuronal loss (NeuN immunofluorescence), axonal loss (Bielschowsky stain), and inflammation (Iba1 immunofluorescence) in three animal groups ( n = 5 per group) on the 1st, 3rd, and 10th day after MCAO. MPF and LFB optical density (OD) were significantly reduced in the ischemic lesion on all days after MCAO relative to the symmetrical regions of the contralateral hemisphere. Percentage changes in MPF and LFB OD in the ischemic lesion relative to the contralateral hemisphere significantly differed on the first day only. Percentage changes in LFB OD and MPF were strongly correlated (R = 0.81, P < 0.001) and did not correlate with other MRI parameters. MPF also did not correlate with other histological variables. Addition of T₂ into multivariate regression further improved agreement between MPF and LFB OD (R = 0.89, P < 0.001) due to correction of the edema effect. This study provides histological validation of MPF as an imaging biomarker of demyelination in ischemic stroke.

Histological validation of fast macromolecular proton fraction mapping as a quantitative myelin imaging method in the cuprizone demyelination model

Cuprizone-induced demyelination in mice is a frequently used model in preclinical multiple sclerosis research. A recent quantitative clinically-targeted MRI method, fast macromolecular proton fraction (MPF) mapping demonstrated a promise as a myelin biomarker in human and animal studies with a particular advantage of sensitivity to both white matter (WM) and gray matter (GM) demyelination. This study aimed to histologically validate the capability of MPF mapping to quantify myelin loss in brain tissues using the cuprizone demyelination model. Whole-brain MPF maps were obtained in vivo on an 11.7T animal MRI scanner from 7 cuprizone-treated and 7 control С57BL/6 mice using the fast single-point synthetic-reference method. Brain sections were histologically stained with Luxol Fast Blue (LFB) for myelin quantification. Significant (p < 0.05) demyelination in cuprizone-treated animals was found according to both LFB staining and MPF in all anatomical structures (corpus callosum, anterior commissure, internal capsule, thalamus, caudoputamen, and cortex). MPF strongly correlated with quantitative histology in all animals (r = 0.95, p < 0.001) as well as in treatment and control groups taken separately (r = 0.96, p = 0.002 and r = 0.93, p = 0.007, respectively). Close agreement between histological myelin staining and MPF suggests that fast MPF mapping enables robust and accurate quantitative assessment of demyelination in both WM and GM.

[THE CHARACTERISTICS OF SYSTEMIC AND LOCAL IMMUNE REACTIONS UNDER HABITUAL NON-CARRYING OF PREGNANCY]

The study was carried out to evaluate clinical informativeness ofstudies of immunological parameters of structural and functional elements of endometrium in complex with profile of embritropic autoimmune antibodies under non-carrying of pregnancy The sampling consisted of 19 women of reproductive age with episodes of non-carrying in first semester. They were examined for inherited thrombophilia and profiles of immune reactivity of natural regulatory auto-antibodies (ELI-P-Complex). The biopsy material of endometrium was subjected to histological and immune histochemical (CD16, CD56, CD68, CB138, estrogen and progesterone receptors) analyses. In women with non-carrying of pregnancy polyclonal immunosuppression, increased level of embriotoxic auto antibodies to Fc- fragment of immunoglobulin, insulin and thyroglobulin are detected. The immune histochemical analysis established expressed decreasing of amount of progesterone receptors of stromal elements of endometrium after spontaneous abortion. The activation of killer activity of decidual lymphocytes under habitual non-carrying of pregnancy was detected too. The positive dependency was established between: expression of progesterone receptors in glandular cells of endometrium and level of anti-spermatic antibodies in blood serum; expression of progesterone receptors in stroma and level of antibodies to human chorial gonadotropin; expression of receptors of estrogens in stroma and level of antibodies to Fc-fragment of immmunoglobulines. The study data permits affirming that evaluation of level of regulatory auto-antibodies is informative at examination of woman after episode of non-carrying of pregnancy. The production of antibodies has direct relationship with pathological processes in endometrium and it can be one of criteria of completeness of pre-conceptional preparation.

[DYNAMICS OF CHANGES IN THE NUMERICAL DENSITY OF PLACENTAL MACROPHAGES DURING UROGENITAL INFECTION IN EARLY PREGNANCY]

The changes in the numerical density of macrophages of maternal (basal decidua) and fetal (Kashchenko-Hofbauer cells) origin were studied in the placenta of women with opportunistic (Ureaplasma urealyticum and Mycoplasma hominis) and pathogenic (Chlamydia trachomatis) urogenital microflora. Histological study of placenta was performed and CD68-immunoreactive cells were detected immunohistochemically in the basal decidua and in the chorionic villi obtained during artificial abortions for non-medical reasons in the 6-8th week of pregnancy (n=136). The results showed no changes in the numerical density of macrophages of maternal origin and a significant decrease in the numerical density of macrophages in the stroma of the chorionic villi, which was associated in Chlamydial infection with a delayed, and in Ureaplasma and Mycoplasma infection - with an accelerated development of the villous tree.

[Cellular composition of decidua basalis infiltrate during early pregnancy in urogenital mycoplasma infection]

The composition and distribution of immunocompetent cells in human decidua basalis at 6-8 weeks of pregnancy was studied immunonohistochemically under normal conditions (control group) and in infection with different mycoplasma species (microbial number> 104 CFU). In all the groups studied, monocytes were most numerous cells; large granular lymphocytes (phenotype: CD56++CD16-CD3), macrophages (CD68+) and immunonegative lymphocytes were observed in equal proportions; the least numerous populations were those of NK-cells (CD56+/-CD16+), plasmocytes and granulocytes. No statistically significant differences were found between the content of these cells in all the investigated groups. The data obtained suggest that mycoplasma infection even characterized by high microbial number, does not cause significant changes in the composition of decidua basalis cellular infiltrate.

[Seasonal variations of nucleic acid content in an experiment on non-pharmacological correction of the hepatic function]

This experiment was preformed on an animal model of CCl4 hepatitis using 320 Wistar rats. The animals underwent combined effect of saprogel and a magnetic field during different seasons. It was shown that non-medicamentous treatment of experimental CCl4 hepatitis had the most pronounced beneficial effect on the synthetic liver function in the winter time. An appreciable suppression of the hepatic function was documented in the spring.