Early intervention with Interleukin-1 Receptor Antagonist Protein modulates catabolic microRNA and mRNA expression in cartilage after impact injury.

OBJECTIVE: The purpose of this controlled laboratory study was to determine the efficacy of Interleukin-1 Receptor Antagonist Protein (IRAP) treatment as an early intervention strategy by examining the changes in microRNA and mRNA expression in cartilage in an ex-vivo porcine knee joint impact model. METHODS: Custom impact device was used to create replicable injury ex-vivo to intact porcine knee joint. Injury was caused by dropping a 10 kg weight one time from 1 m directly above the knee in extension. One hour after impact 20 µg/ml IRAP solution was intra-articularly injected. At 8 h post-injury, cartilage samples were harvested for cell viability and genetic expression analysis. Genetic expression of miR-27b, miR-140, miR-125b, ADAMTS-4, ADAMTS-5, MMP-3, IL-1ß, and TNF-α were analyzed by RT-PCR. Cell viability image analysis was performed using ImageJ software. Groups were compared by analysis of variance (ANOVA) followed by Tukey's post-hoc test. A P-value <0.05 was considered significant. RESULTS: At 8 h after IRAP treatment, expressions of ADAMTS-4, ADAMTS-5, MMP-3, IL-1ß, and TNF-α in cartilage were significantly down-regulated from injury group (all P < 0.001). MiR-140, miR-125b, and miR-27b expressions were significantly up-regulated after treatment as compared to control and injury groups (all P < 0.001). CONCLUSION: This study demonstrates that IRAP treatment administered during acute phase of cartilage impact injury increases expression levels of miR-140, miR-125b, and miR-27b in cartilage, indicating increased inhibition of their respective matrix-degrading enzymes. Clinically, these findings support the potential of IRAP treatment as an early intervention strategy for the prevention of cartilage degeneration after impact injury.

New insights into the role of sex steroid hormones in pregnancy: possible therapeutic approach by sex steroid hormones for the treatment of both preeclampsia and preterm labor.

Fetal peptide hormones are essential for the development of fetus, which increase in accordance with pregnancy term. Concentration of these hormones within the feto-placental unit is normally higher than that of maternal circulation. Since these hormones are biologically active, the leakage of these hormones into the maternal circulation is regulated by degradation activity by placental aminopeptidases, in order to maintain the balance between carriage of pregnancy and onset of labor.Because the concentration of these hormones, being regulated by the amount of endogenous production and by physiological degradation by enzymes in the blood and tissue, the balance between production and degradation is a definitive element for maintaining normal gestation and term delivery.The changes of the balance between fetal angiotensin II (A-II) and vasopressin (AVP) andA-II and AVP degrading enzymes, between aminopeptidase A (APA) and placental leucine aminopeptidase( P-LAP) - in the placenta and maternal blood due to fetal stress such as hypoxia - are the provable causes of preeclampsia or preterm labor.Induction of APA and P-LAP by estradiol benzoate (E2) and progesterone (P) from placenta has been demonstrated. They are involved in the regulation of fetal peptide hormones via placental aminopeptidases in homeostasis of pregnancy.Recently it was shown that both APA and P-LAP could be potentially safe and effective drugs for preeclampsia and preterm labor. The authors' proposed sex steroid treatment with dose increasing manner by gestational week (sex steroid treatment) for severe preeclampsia and preterm labor could be candidates replacing conventional treatments. In light of lacking safe and effective medication, the proposed sex steroid treatment is worthwhile for the prospective controlled studies for the treatment of both preeclampsia and preterm labor.

Reproductive cycle of the Neotropical Crotalus durissus terrificus: I. Seasonal levels and interplay between steroid hormones and vasotocinase.

Crotaline snakes present delayed fertilization and sperm storage because secondary vitellogenesis is not completed by the time of mating. The release of vitellogenesis and synchrony between ovulation and fertilization suggest a steroidal modulation. We investigated changes of sexual steroid levels during reproduction in the Neotropical rattlesnake Crotalus durissus terrificus, analyzing macroscopical variations of reproductive condition (vitellogenesis, pregnancy, and post-partum) and plasma levels of estradiol, progesterone, and vasotocinase cystine aminopeptidase (CAP) activity over 2 years. Data showed 44.4% non-reproductive snakes (40.1% primary vitellogenesis and 4.3% post-partum) and 55.6% reproductive (36.8% secondary vitellogenesis and 18.8% pregnant). Estradiol was low in spring and summer, increasing in autumn till it peaked in winter. Estradiol in secondary vitellogenesis was significantly higher than in primary vitellogenesis, or in pregnant and post-partum females, Progesterone dropped significantly in autumn compared to summer, winter, and spring. Pregnant females showed the highest levels of progesterone compared to primary or secondary vitellogenesis, or post-partum females. CAP activity showed lowest values in reproductive females in autumn and greatest levels in post-partum females. A significant negative linear relationship was obtained between CAP activity and estradiol. The combination of morphological observations, levels of steroids and CAP activity allowed us to suggest a similar morphological reproductive pattern between temperate and tropical rattlesnakes, and to infer the role of estradiol, progesterone and CAP activity on vitellogenesis, gestation and sperm storage, respectively.

Reproductive cycle of the Neotropical Crotalus durissus terrificus: II. Establishment and maintenance of the uterine muscular twisting, a strategy for long-term sperm storage.

Crotaline snakes store sperm by means of a uterine musculature twisting (UMT). We investigated the influence of plasma levels of estradiol and progesterone and vasotocinase cystine aminopeptidase (CAP) activity on UMT formation and maintenance, and the in vitro uterine reactivity for AVT in Crotalus durissus terrificus in primary or secondary vitellogenesis with or without UMT. Frequency of females in secondary vitellogenesis with UMT is significantly higher than in primary one. Estradiol levels did not vary in all conditions studied, however, significantly low levels of progesterone were found in snakes in secondary vitellogenesis with UMT compared to those without it. UMT is always observed when high levels of estradiol and low levels of progesterone are detected. CAP activity did not change in the presence of UMT. AVT produced concentration-response contractions of the isolated uterus of snakes in all stages analysed and the pD2 value and maximum contractile response were significantly higher in primary vitellogenesis without UMT than in other reproductive conditions, indicating that uterus of those snakes presents a higher contractile capacity which may favour UMT establishment. In conclusion, we show a relationship of UMT and estradiol/progesterone balance and a possible participation of AVT in UMT formation and maintenance in the Neotropical rattlesnake.