Polymeric nanoparticle formulation of Octapeptide (NP-OP): In vitro release and in vivo effect in common marmosets, Callithrix jacchus Linn.

yielded an average particle size of 120 nm with 70% encapsulation-efficiency. In vitro release profile of NP-OP showed sustained release of OP for 21 days. In vivo anti-fertility studies were conducted in marmosets. Results indicated that control animals conceived in the same cycle while two of three treated animals failed to conceive in treatment cycle. The in vivo studies thus corroborate with in vitro release of OP, demonstrating its anti-fertility activity in 66% of animals.

Apoptosis in endometrium of mouse during estrous cycle.

The present study was carried out to evaluate apoptosis in endometrium and to correlate these changes with the circulating levels of estradiol and progesterone in the mouse. Apoptosis was observed in various compartments of mouse uterus i.e. stroma, glandular epithelium and luminal epithelium depending on the stage of cycle. Stromal cell apoptosis was observed during various stages of cyclicity except on estrus day. Luminal epithelial cells showed apoptotic changes during all stages of cyclicity except on diestrus day. During metestrus, apoptosis was observed in glandular and luminal epithelia as well as stromal cells. Steroid antagonists such as tamoxifen and onapristone altered the apoptotic changes in the uterus. The results suggest that epithelial cell apoptosis is regulated by estrogen while stromal cell apoptosis is under the control of progesterone.

Potential researchable areas in ARTs--oocyte maturation and embryo development.

Infertility is a commonly encountered situation occurring equally in both sexes. In vitro fertilization and embryo transfer (IVF-ET) and other assisted reproductive technologies (ARTs) have enhanced the possibilities for successful treatment to tackle infertility. However, ARTs currently face limitations due to the fact that although success rate is high for the initial stages such as ovulation induction and fertilization, it dwindles progressively so that the success rate of a take home baby is as low as 15-20%. Research centred around various stages in an IVF programme is therefore necessary to devise protocols that ensure a higher success rate. This review takes a look at the potential areas currently under research in the field of ARTs, such as, in vitro oocyte maturation, oocyte/embryo cryopreservation, embryo culture, preimplantation genetic diagnosis. Their applications, in clinical conditions such as cancer, have been discussed.

Localization of estrogen and progesterone receptors in the endometrium of common marmosets Callithrix jacchus.

In the present study, changes in the immunohistochemical localization of endometrial estrogen receptor (ER) and progesterone receptor (PR) during various stages of the ovarian cyclicity in common marmoset, have been reported. Ovarian cyclicity was monitored by estimating plasma estradiol and progesterone. During the early follicular phase, weak ER immunolocalization was observed in the endometrial stroma. During the late follicular phase under the influence of rising estradiol levels, stromal ER localization was intense. During the luteal phase, ER localization was absent in the stroma indicating that high concentrations of progesterone suppressed ER. PR localization was not observed in the stroma during the early follicular phase, while weak staining was seen in the stroma during the late follicular phase. PR localization was maximum during the mid luteal phase. However in marmoset, endometrial ER and PR localization was restricted only to the stroma. This unique feature may be due to the characteristic reproductive profile of this nonmenstruating species and needs to be studied further. Thus it can be hypothesized that in the marmoset endometrium, steroid hormone mediated effects possibly occur directly in the stroma and are then transmitted to the epithelium by autocrine/paracrine action of growth factors and cytokines.

Subpopulations of physiological and ovarian follicular fluid peptide induced apoptotic cells.

Ovarian follicular fluid peptide (OFFP) purified from sheep ovaries enhances apoptotic changes in ovarian granulosa cells of mice. To get an insight into the cell subpopulations responding to OFFP, the heterogeneity of granulosa cells was resolved. Subpopulations of granulosa cells were obtained from ovaries of immature mice treated with PMSG alone and autopsied 48 hr (control) and 72 hr after injection (atretic) and from animals injected OFFP 24 hr after PMSG injection and autopsied 24 hr later (OFFP treated) by separation on discontinuous Percoll gradient. Four fractions were collected and studied for their relative distributions and percent apoptotic cells measured by acridine orange staining. FSH binding to granulosa cell (sedimenting as a major) fraction was studied by radio receptor assay. There is a difference in densities in subpopulations of apoptotic cells induced by OFFP and those generated during the physiological process of atresia. This difference may be a reflection of different granulosa cell subpopulations involved in peptide response or differences in phases as the cells transit from normal to apoptotic phenotype. FSH binding to granulosa cells from OFFP treated animals was significantly less than those from control and atretic group.

Characterization and localization of estrogen and progesterone receptors of human fallopian tube.

The cellular distribution of estrogen and progesterone receptors (ER and PR) in the human fallopian tube was investigated by immunohistochemical localization with specific monoclonal antibodies. Nuclear immunostaining was observed. Intense PR immunostaining was seen in tissues obtained at mid cycle and luteal stages of the normal menstrual cycle. On the other hand, enhanced staining for ER was seen in early follicular phase and mid cycle. Menopausal tissues showed negligible staining for both ER and PR. The ER and PR were characterized for their molecular size, anatomical distribution and levels during the menstrual cycle and in menopause. ER protein was present throughout the cycle and also during menopause. Western blot analysis revealed two forms of ER approximately 66 kDa and a truncated from approximately 49 kDa in hFT. Presence of A [approximately 90 kDa] and B [approximately 120 kDa] isoforms of human PR was detected. Follicular and early luteal tissue possessed relatively high concentration of immunoreactive PR whereas it was almost undetectable in menopausal tissues. These results suggests that ER and PR are regulated by the changing ovarian steroid hormones.

Effect of estrogen and progesterone on newly synthesised and released human fallopian tube specific proteins.

Current study was carried out to identify the profile of newly synthesized and released proteins by human fallopian tube (hFT). Results indicated that hFT during menopause synthesised and released only 2-3 proteins as against several proteins ranging from molecular weight (MW) approximately 20 to approximately 130 kD during normal menstrual cycle. In vitro addition of estradiol-17 beta (E2) resulted in synthesis and release of a number of proteins including specific protein of MW 110-130 kD. Addition of progesterone (P) however, led to inhibition of protein synthesis and a combination of E2 and P negated the effect of the latter. An alteration in oviductal secretory protein-profile following addition of E2 in vitro were similar to that observed during normal menstrual cycle.

Autoimmune disorders of the ovary.

Infertility and ovarian disorders may occur not only due to imbalance in the steroid hormones but also due to the alteration in the immune function. A number of autoimmune disorders of the ovary, such as polycystic ovarian syndrome, premature ovarian failure and autoimmune oophoritis, have been documented. Both the cell mediated and humoral immune responses play an important role in these disorders. Cytokines secreted by the immune cells could have an adverse effect on ovarian steroidogenesis whereas the production of pathogenic T cells could lead to autoimmune disease of the ovary. Autoantibodies to granulosa and theca cells as well as zona pellucida of the oocyte have also been documented in women indicating that autoimmunity plays an important role in infertility. Thus the endocrine and the immune system work hand in hand to regulate ovarian function.

Immunoendocrine interrelationship--effect of ovariectomy on spleen and thymus in mouse.

Increase in the weights of spleen were observed 15 days after ovariectomy in adult as well as immature mice. However, no corresponding change was recorded in the splenocyte count. Morphological alterations in the shape of germinal centres was noted after ovariectomy in adult and immature mice. Increase in weight of the thymus could be demonstrated in adult mice only, with a concomitant enlargement of cortical and medullary region.

Localization and detection of ovarian follicular fluid protein in follicles of human ovaries.

Human ovarian follicular fluid protein has been partially purified and the active fraction designated as hGF2. Using specific polyclonal antiserum to hGF2, it was observed to be localized immunohistochemically in the granulosa cells of medium but not large follicles of human ovary. The hGF2 levels were estimated by ELISA in serum and follicular fluid of 10 gonadotropin-stimulated women recruited for IVF-ET programme. The results revealed a 3-fold increase in the concentration of hGF2 in follicular fluid compared to that in serum of these patients. These data indicate that the protein is secreted by granulosa cells and plays an important role in the regulation of follicular maturation and ovulation.

Suppression of steroidogenesis in mice granulosa cells by a synthetic nonapeptide fragment of human seminal plasma inhibin.

A synthetic nonapeptide, which is C-terminal sequence of 94-amino acid of prostatic inhibin peptide was tested for progesterone and estrogen secretion by mouse granulosa cell cultures. Nonapeptide suppressed the progesterone and estrogen synthesis, the magnitude of suppression was highest at 5 ng dose level for progesterone and 50 ng dose level for estradiol. The study suggests that, nonapeptide exerts its effect by impairing the binding of FSH to granulosa cell receptors.