Protective effects of Yerba mate (IIex paraguariensis) on prostate cancer development.

OBJECTIVES: Prostate cancer (PCa) is the most common adenocarcinoma in men >50 y of age. It has a long latency period, which provides time for preventive strategies like incorporating healthy eating habits. Yerba mate (YM) intake has been associated with numerous health benefits. Since YM is one of the most popular infusions in Argentina, the of this study was to examine the influence of YM on PCa development. METHODS: We carried out an in vivo model of PCa through subcutaneous inoculation of transgenic adenocarcinoma of the mouse prostate-C1 cells in C57BL/6 mice. Subsequently, the animals were divided into two groups: mate (25 mg/mL of YM in drinking water, n = 15), and control (only drinking water, n = 15). We also developed an in vitro model to study the direct effects of YM on three human PCa cell lines: lymph node carcinoma of the prostate (LNCaP), PC-3, and DU-145. RESULTS: Our in vivo model showed that YM intake slightly reduced body weight, increased the latency of tumor appearance (P <0.01), and diminished the tumor volume (P <0.05) compared with the control group. In agreement, the expression of proliferating cell nuclear antigen, and nuclear estrogen receptor α were lower in the tumors of the mate animals (P <0.05). In vitro, YM decreased the viability, proliferation, and adhesion of the three tumor cell lines (P < 0.001) and retarded the migration of LNCaP (P <0.05) and DU-145 (P <0.005), without modifying the migration of PC-3 cells. CONCLUSIONS: YM showed anticancer effects in vitro and in vivo and were more effective on the androgen-sensitive cell line (LNCaP).

Placental leukocyte infiltration accompanies gestational changes induced by hyperthyroidism.

In brief: The endocrine and immunological disruption induced by hyperthyroidism could alter gestation, placenta, and fetal development. This study suggests an immunological role of thyroid hormones in gestation. Abstract: Thyroid dysfunctions lead to metabolic, angiogenic, and developmental alterations at the maternal-fetal interface that cause reproductive complications. Thyroid hormones (THs) act through their nuclear receptors that interact with other steroid hormone receptors. Currently, immunological regulation by thyroid status has been characterized to a far less extent. It is well known that THs exert regulatory function on immune cells and modulate cytokine expression, but how hyperthyroidism (hyper) modulates placental immunological aspects leading to placental alterations is unknown. This work aims to throw light on how hyper modulates immunological and morphological placental aspects. Control and hyper (induced by a daily s.c. injection of T4 0.25 mg/kg) Wistar rats were mated 8 days after starting T4 treatment and euthanized on days 19 (G19) and 20 (G20) of pregnancy. We removed the placenta to perform qPCR, flow cytometry, immunohistochemistry, Western blot and histological analysis, and amniotic fluid and serum to evaluate hormone levels. We observed that hyper increases the fetal number, fetal weight, and placental weight on G19. Moreover, hyper induced an endocrine imbalance with higher serum corticosterone and changed placental morphology, specifically the basal zone and decidua. These changes were accompanied by an increased mRNA expression of glucocorticoid receptor and monocyte chemoattractant protein-1, an increased mRNA and protein expression of prolactin receptor, and an increase in CD45+ infiltration. Finally, by in vitro assays, we evidenced that TH induced immune cell activation. In summary, we demonstrated that hyper modulates immunological and morphological placental aspects and induces fetal phenotypic changes, which could be related to preterm labor observed in hyper.

Desmoglein-4 Deficiency Exacerbates Psoriasiform Dermatitis in Rats While Psoriasis Patients Displayed a Decreased Gene Expression of DSG4.

Desmogleins are involved in cell adhesion conferring structural skin integrity. However, their role in inflammation has been barely studied, and whether desmoglein-4 modulates psoriasis lesions is completely unknown. In this study, we assessed the impact of desmoglein-4 deficiency on the severity of imiquimod (IMQ)-induced skin inflammation and psoriasiform lesions. To this end, desmoglein-4-/- Oncins France Colony A (OFA) with Sprague-Dawley (SD) genetic background were used. Additionally, human RNA-Seq datasets from psoriasis (PSO), atopic dermatitis (AD), and a healthy cohort were analyzed to obtain a desmosome gene expression overview. OFA rats displayed an intense skin inflammation while SD showed only mild inflammatory changes after IMQ treatment. We found that IMQ treatment increased CD3+ T cells in skin from both OFA and SD, being higher in desmoglein-4-deficient rats. In-depth transcriptomic analysis determined that PSO displayed twofold less DSG4 expression than healthy samples while both, PSO and AD showed more than three-fold change expression of DSG3 and DSC2 genes. Although underlying mechanisms are still unknown, these results suggest that the lack of desmoglein-4 may contribute to immune-mediated skin disease progression, promoting leukocyte recruitment to skin. Although further research is needed, targeting desmoglein-4 could have a potential impact on designing new biomarkers for skin diseases.

Pigment epithelium derived factor (PEDF) expression in the male tract of Wistar rats.

Pigment epithelium derived factor (PEDF) expression has been described in many organs as showing neurotrophic, anti-angiogenic, anti-apoptotic, anti-inflammatory, anti-oxidant and pro-cell survival properties. However, references to its activity in the male reproductive system are scarce. We aimed to characterize the expression of PEDF in the male reproductive tract of Wistar rats by using RT-PCR, western blot and immunostaining and also evaluate the effect of flutamide in PEDF expression. We found that PEDF is expressed in the epididymis, prostate and seminal vesicles in Wistar rats, but notably not in the testes. Under the effect of flutamide PEDF expression decreased, recovering by suppressing the antiandrogen. The epididymis is an essential organ in sperm maturation-storages. The role of PEDF in this physiological process has not been fully elucidated yet, but considering that in other systems PEDF has anti-apoptotic, anti-oxidants and pro-cell survival properties, its expression along the epididymis could play a role in the protection of spermatozoa while they are stored.

Chronic exposure to environmental stressors enhances production of natural and specific antibodies in rats.

Although the immunosuppressive effect of chronic stress has been established, a stress response that downregulates the whole immune system does not make biological sense, especially if an animal has to endure difficult times in which there is also increased infection risk. At high animal densities, animals are faced simultaneously with food restriction (FR), social conflict (SC), and greater parasite-pathogen exposure. We hypothesized that the stress response to chronic stressors that covary with infection risk is not entirely immunosuppressive. Our prediction was that a chronically stressed animal would respond by enhancing innate defenses, while reducing investment in acquired immunity. In a laboratory setting, rats were exposed to prolonged FR and/or SC, and natural and specific antibody levels were repeatedly measured. Our prediction was fulfilled only partly, as FR and SC interacted to enhance natural antibodies, but rats exposed to either or both stressors also showed significantly higher levels of specific antibodies. These results suggest that, in the rat, chronic stress results in a prioritization of both innate and acquired humoral defenses, which makes biological sense provided the stressors examined usually signal an increased infection risk.

Simultaneous activation of PLA2 and PLC are required to promote acrosomal reaction stimulated by progesterone via G-proteins.

The acrosome reaction (AR) is a special exocytotic process promoted by signal transduction pathways studied in many laboratories. Progesterone (P4) is one of the trigger molecules proposed. Upon the binding of P4 to its receptor, several molecules could be activated, including G-proteins, phospholipase A(2) (PLA(2)), and phospholipase C (PLC). The role of these molecules was analyzed in this study using the Chlortetracycline (CTC) protocol to detect and quantify the AR. Incubation of capacitated sperm cells with GTPgammas (GTPgammas, a mimetic of G-protein activation), arachidonic acid (AA, product of PLA(2) action), or phorbol ester (PMA, an activator of PLC) for 15 min increased the AR to a similar percentage as P4. Conversely, a decrease in the AR was detected when sperm cells were incubated with P4 after preincubation with: GDPbetaS (GDP, an inhibitor of G-protein activation), ONO RS-82 (ONO, an inhibitor of PLA(2)), or neomycin (Neo, an inhibitor of PLC) for 15 min. To analyze the activation sequence of G proteins, PLA(2), and PLC combinations of these mimetic/inhibitors were used during successive incubation periods. Inhibition promoted by GDP, ONO, and Neo were overcome by 15-min incubation with GTPgammas, AA, or PMA, respectively. But GTPgammas or P4 did not reverse the inhibition due to incubation with Neo and ONO. Interestingly, this dual inhibition was reverted by another 15-min incubation with AA or PMA. Results presented here could indicate that the AR triggered by P4 is driven by activation of G-proteins, that in turn activate PLA(2) and PLC simultaneously, that finally promote acrosomal exocytosis.

Progesterone receptor availability in mouse spermatozoa during epididymal transit and capacitation: ligand blot detection of progesterone-binding protein.

The goals of the present study were to determine the availability of progesterone (P4) receptor (P4r) in mouse sperm during maturation and capacitation and to make the first steps toward a characterization of P4r. It has been proposed that P4 is able to induce an acrosomal reaction (AR) by using a membrane P4r. This induction was verified in sperm isolated from the cauda epididymis (fully mature) when incubated in specific conditions that capacitate sperm. First, we set up the conditions in our laboratory to induce an AR in mature and capacitated sperm triggered by P4 that was detected by a chlortetracycline (CTC) assay. Then, we examined sperm isolated from the caput epididymis (immature) incubated under conditions that support cauda sperm capacitation and found that the AR could not be detected. Moreover, P4 was unable to induce the AR when it was applied to sperm isolated from either region and incubated under conditions that did not support capacitation. These results can be explained by changes in P4r availability. A suitable marker for P4r is the gold (Au)-P4 complex. This marker shows a binding capacity that can be visualized directly by electron microscopy (EM) and indirectly by silver-enhanced methods with light microscopy. The Au-P4 complex was localized in capacitated cauda sperm at the dorsal edge of the head. Using these techniques, we observed a significant decrease in both noncapacitated cauda sperm and caput sperm (whether incubated in capacitating media or not). Genomic P4r could be responsible for the signal detected, but antibodies against the P4 nuclear receptor did not recognize any sites in the sperm by immunostaining methodology. Instead, a 44-kd protein band was detected in the sperm by a ligand blot assay. In conclusion, P4 promotes the AR in capacitated cauda sperm but is unable to do so in noncapacitated or immature sperm because the availability of P4r increases during epididymal transit and after capacitation. The P4r responsible for this behavior is different from a classical nuclear receptor-on the basis of the immunostaining results-and is probably a protein close to 44 kd-on the basis of the ligand assay results.