Horse Placental Extract Enhances Neurogenesis in the Presence of Amyloid ß.

Human placental extract and animal-derived placental extracts from pigs and horses host a wide range of biological activities. Several placental products are used as medicines, cosmetics, and healthcare substances worldwide. However, the use of placental extracts for neuronal functioning is currently not established because the number of relevant studies is limited. A few previous reports suggested the neuroprotective effect and dendrite genesis effect of placental extract. However, no studies have reported on neurogenesis in placental extracts. Therefore, we aimed to investigate the effects of horse placental extract on neurogenesis, and we examined the protective effect of the extract on the onset of memory disorder. A horse placental extract, JBP-F-02, was used in this study. JBP-F-02 treatment dose-dependently increased the number of neural stem cells and dendrite length under Aß treatment in primary cultured cortical cells. The oral administration of JBP-F-02 to a 5XFAD mouse model of Alzheimer's disease at a young age significantly prevented the onset of memory dysfunction. This study suggests that the extract has the potential to prevent dementia.

A Novel Heptapeptide, GPPGPAG Transfers to the Brain, and Ameliorates Memory Dysfunction and Dendritic Atrophy in Alzheimer's Disease Model Mice.

We investigated the effects of a heptapeptide, GPPGPAG, on memory improvement and neuritic regeneration in Alzheimer's disease models to evaluate its potency as a new anti-Alzheimer's disease (AD) therapy. The anti-AD effects of GPPGPAG were evaluated in Aß-treated cortical neurons and 5XFAD, a mouse model of AD. Exposure of cortical neurons to Aß25-35 for 3 days resulted in atrophy of axons and dendrites. Treatment with GPPGPAG improved the dendritic atrophy of Aß-treated cortical neurons, but not axonal atrophy. Postsynaptic and presynaptic densities under Aß1-42 exposure were increased by GPPGPAG post treatment. Oral administration of GPPGPAG to 5XFAD mice for 15 days improved significantly object recognition memory and dendritic density. Direct infusion of GPPGPAG into the lateral ventricle of 5XFAD mice for 28 days improved object recognition memory. Following oral administration of GPPGPAG in mice, the undigested heptapeptide was detected in the plasma and cerebral cortex. Analysis of target protein of GPPGPAG in neurons by DARTS method identified 14-3-3ε as a bound protein. The protective effect of GPPGPAG on Aß1-42-induced dendritic atrophy was canceled by knockdown of 14-3-3ε. Taken together, these results suggest that GPPGPAG is orally available, transfers to the brain, and ameliorates memory dysfunction in AD brain, which is possibly mediated by 14-3-3ε-related dendritic restoration.

Diosgenin content is a novel criterion to assess memory enhancement effect of yam extracts.

Several studies have suggested that some kind of Dioscorea species (yam) or yam-contained herbal medicines have cognitive enhancement effect. However, it has been unknown what is a crucial factor for cognitive enhancement in each Dioscorea species. In this study, we aimed to investigate whether one of the main and brain-penetrating components in yams, diosgenin, can be a novel criterion to assess memory enhancement effect of yam extracts. Although our previous studies showed that administration of diosgenin or diosgenin-rich yam extract enhanced cognitive function in normal mice and healthy humans, we have never evaluated whether the effect depends on diosgenin content or not. Therefore, we compared memory enhancement effects of low diosgenin-contained general yam water extract with diosgenin-rich yam extract on cognitive function in normal mice. We found that unlike diosgenin-rich yam, administration of general yam water extract did not enhance object recognition memory in normal mice. LC-MS/MS analyses revealed that after administration of general yam, diosgenin concentration in the brain did not reach to the effective dose because of the low diosgenin content in the original yam extract. On the other hand, when diosgenin was artificially added into general yam, the extract showed memory enhancement in normal mice and promoted neurite outgrowth in neurons. Our study suggests that diosgenin is actually an active compound in yams for memory enhancement, and diosgenin content can be a criterion for predicting cognitive enhancement effect of yam extracts.

Relaxin-2 May Suppress Endometriosis by Reducing Fibrosis, Scar Formation, and Inflammation.

BACKGROUND: Relaxin (RLX)-2, produced by the corpus luteum and placenta, is known to be potentially effective in fibrotic diseases of the heart, lungs, kidneys, and bladder; however, its effectiveness in endometriosis has not yet been investigated. In the present study, we conducted a comprehensive study on the effect of RLX-2 on endometriosis. We checked the expressions of LGR-7, a primary receptor of RLX-2, in endometriomas using immunohistochemistry. Endometriotic stromal cells (ESCs) purified from surgical specimens were used in in vitro experiments. The effects of RLX-2 on ESCs were evaluated by quantitative-PCR, ELISA, and Western blotting. Gel contraction assay was used to assess the contraction suppressive effect of RLX-2. The effect of RLX-2 was also examined in the endometriosis mouse model. LGR-7 was expressed in endometriotic lesions. In ESCs, RLX-2 increased the production of cAMP and suppressed the secretion of interleukin-8, an inflammatory cytokine, by 15% and mRNA expression of fibrosis-related molecules, plasminogen activator inhibitor-1 (PAI-1), and collagen-I by approximately 50% (p < 0.05). In the gel contraction assay, RLX-2 significantly suppressed the contraction of ESCs, which was cancelled by removing RLX-2 from the medium or by adding H89, a Protein Kinase A (PKA) inhibitor. In ESCs stimulated with RLX-2, p38 MAPK phosphorylation was significantly suppressed. In the endometriosis mouse model, administration of RLX-2 significantly decreased the area of the endometriotic-like lesion with decreasing fibrotic component compared to non-treated control (p = 0.01). RLX-2 may contribute to the control of endometriotic lesion by suppressing fibrosis, scar formation, and inflammation.

Serum Brain-derived Neurotrophic Factor Levels Mirror Bone Mineral Density in Amenorrheic and Eumenorrheic Athletes.

Amenorrhea and osteoporosis are strongly associated in female athletes. Amenorrheic women show lower serum levels of brain-derived neurotrophic factor (BDNF) than eumenorrheic women. BDNF is known to regulate bone tissue development and remodeling; thus, athletes with low serum BDNF levels may show low bone mass. This study investigated the associations between serum BDNF, estradiol, and bone mineral density (BMD) in female athletes. This study included 160 elite female athletes (21.7±4.3 years). Serum levels of BDNF and estradiol were in 195 blood samples obtained from 132 eumenorrheic athletes (EA) and 63 amenorrheic athletes (AA). BMD was measured in the radius, lumbar spine, pelvis, and legs using dual-energy X-ray absorptiometry. AA showed significantly lower serum BDNF levels than EA (p=0.017). Serum BDNF levels were positively and significantly associated with both serum estradiol levels (p=0.0004) and the BMD measured at all sites (all p<0.05). 10 AA received transdermal estrogen therapy, and serum BDNF levels were measured at baseline and 6 months after therapy. Hormone-treated AA demonstrated a significant increase in serum BDNF levels after 6 months (p=0.022). Thus, serum BDNF levels may be associated with decreased BMD and serve as an indicator of the therapeutic effect of estradiol supplementation in female athletes with osteoporosis.

Sphingosine 1 Phosphate (S1P) Increased IL-6 Expression and Cell Growth in Endometriotic Cells.

OBJECTS: There is growing evidence that sphingosine 1-phosphate (S1P) is involved in inflammatory diseases. As endometriosis is known as an inflammatory disease, we investigated the role of S1P system in the development of endometriosis. METHODS: The expression of sphingosine kinase (SphK) 1 in endometriosis lesions was examined by immunohistochemistry. The cystic fluid of ovarian cysts/tumors were obtained to measure S1P concentrations. Endometriotic stromal cells (ESC) derived from endometrioma were used for in vitro experiments. RESULTS: Sphingosine kinase 1 was detected in epithelium and stromal cells of endometriotic lesions. The mean S1P concentration in the cystic fluid of endometriomas was higher than that in nonendometriomas significantly (98.2 nM vs less than 1.5 nM, P < .01). Interleukin-1ß (IL-1ß) or transforming growth factor-ß exhibited 2.7-fold and 11.5-fold increase in SphK1 messenger RNA (mRNA) expression in ESC, respectively (P < .01). Higher dose of S1P (125nM) increased the cell number of ESC by 20%, and low dose of S1P (1.25 nM and 12.5 nM) induced IL-6 mRNA production and IL-6 secretion by ESC dose-dependently. JTE013, an antagonist for S1PR2, partially suppressed IL-6 induction by S1P (P < .05). JTE013 and VPC23019, an antagonist for S1PR1 and S1PR3, suppressed the ESC proliferation induced by S1P. CONCLUSION: The present study for the first time proved that the SphK-S1P-S1PR axis play a role of accelerating inflammation and growth of endometriotic cells.

RSK-MASTL Pathway Delays Meiotic Exit in Mouse Zygotes to Ensure Paternal Chromosome Stability.

During vertebrate fertilization, sperm chromatin remodeling occurs concomitantly with maternal chromosome segregation at anaphase II, leading to simultaneous formation of two pronuclei. In mammals, these processes take much longer than in other vertebrates. Here, we explore the molecular basis and physiological importance of this mammalian-specific temporal regulation using mouse oocytes. We demonstrate the involvement of protein phosphatase in temporal regulation. Early onset of pronuclear formation causes paternal-biased abnormalities in pronuclear morphology and chromosome segregation at the first mitosis. After oocyte activation, CDK1-MASTL-ENSA, a protein phosphatase 2A-suppressive pathway, remains active despite the absence of cyclin B and contributes to delayed pronuclear formation. Sustained activation of MASTL involves ribosomal S6 kinase (RSK)-mediated phosphorylation of Thr297, which is conserved only among mammalian MASTLs. Our findings reveal the role of RSK in mouse oocytes, showing that the RSK-MASTL pathway allows mammalian-specific prolonged meiotic exit and ensures the faithful conversion from sperm to paternal pronuclei.

PAI-1 in granulosa cells is suppressed directly by statin and indirectly by suppressing TGF-ß and TNF-α in mononuclear cells by insulin-sensitizing drugs.

PROBLEM: Plasminogen activator inhibitor-1 (PAI-1) is elevated in women with polycystic ovary syndrome (PCOS), but the regulation in granulosa cells (GCs) is unclear. METHOD OF STUDY: PAI-1 expression in PCOS ovaries was investigated immunohistologically. PAI-1 expressions in HGrC1, a human GC cell line, were investigated at mRNA and activity levels. The expressions of TGF-ß and TNF-α in peritoneal fluid mononuclear cells (PFMCs) were measured with quantitative PCR. RESULTS: Little PAI-1 expression is observed in healthy GCs, whereas GCs of PCOS and atretic follicle exhibit distinct expression in vivo. In vitro study using HGrC1 shows that TGF-ß and TNF-α increase PAI-1 mRNA and its activity, and both together exhibit a synergistic effect. The expression of PAI-1 mRNA is suppressed by simvastatin. Moreover, insulin-sensitizing drugs (metformin, pioglitazone, and rosiglitazone) suppress LPS-induced TGF-ß and TNF-α mRNA expression in PFMC. CONCLUSION: Statin and insulin-sensitizing drugs may provide a potential therapy for PCOS via down-regulation of PAI-1 expression in GCs and down-regulation of TGF-ß and TNF-α expression in PFMC, respectively.

Oral contraceptive therapy reduces serum relaxin-2 in elite female athletes.

AIM: Recent investigations have demonstrated that athletes with high relaxin-2 levels have a high risk of anterior cruciate ligament injuries, while athletes taking oral contraceptives (OC) have low relaxin-2 levels. It has not yet been clarified whether taking OC reduces relaxin-2 levels. The purpose of this study was to investigate changes in relaxin-2 levels in athletes taking OC. METHODS: Levels of relaxin-2, estradiol, progesterone, luteinizing hormone and follicle-stimulating hormone were measured in serum samples (n = 183) from 106 elite female athletes. Five athletes with serum relaxin-2 concentrations > 6 pg/mL during the luteal phase were recruited to assess the effect of OC therapy. RESULTS: Serum relaxin-2 concentrations were significantly higher during the luteal phase (n = 57) than in the follicular phase (n = 72), or in athletes on OC therapy (n = 10) (P < 0.001, P < 0.001 and P < 0.05, respectively). In the luteal phase, 36.8% (21/57) of the athletes had relaxin levels > 6 pg/mL. In 23 athletes, serum relaxin-2 concentrations were measured during both the follicular and luteal phases, revealing that relaxin-2 levels were significantly higher in the luteal phase compared with the follicular phase. In 5 out of 23 athletes, serum relaxin-2 concentrations were > 6 pg/mL in the luteal phase and during the second cycle of OC therapy, relaxin-2 concentrations decreased dramatically to below the detection limit (0.26 pg/mL). CONCLUSIONS: High serum relaxin-2 concentrations were only detected during the luteal phase. In athletes with high relaxin-2 concentrations during the luteal phase, OC therapy decreased serum relaxin-2 levels.

Alpha-7 nicotinic acetylcholine receptor (nAChR) agonist inhibits the development of endometriosis by regulating inflammation.

OBJECTIVE: We investigated α-7 nAchR expression in human peritoneal macrophages and examined whether activation of nAchR might be a new therapy for endometriosis. MATERIALS AND METHODS: Human peritoneal fluid mononuclear cells (PFMC) were stimulated with lipopolysaccharide (LPS) in the presence of α-7 nAChR agonists. In a murine endometriosis model, α-7 nAChR modulators were administered. RESULTS: Human PFMC expressed α-7 nAChR at the mRNA and protein levels. Activation of α-7 nAChR with its agonists led to significant (P<.01) suppression of LPS-induced interleukin (IL) -1ß expression. In a murine endometriosis model, one week after inoculation of endometrium to the peritoneal cavity, α-7 nAChR agonist significantly suppressed the expression of IL-1ß mRNA (P<.01), which was negated when α-7 nAChR antagonist was administered simultaneously. α-7 nAChR agonist significantly suppressed the formation of endometriotic lesions, which was reversed with α-7 nAChR antagonist. CONCLUSION: Activation of nAChR might be a new candidate for treatment of endometriosis.

The microtubule-binding and coiled-coil domains of Kid are required to turn off the polar ejection force at anaphase.

Mitotic chromosomes move dynamically along the spindle microtubules using the forces generated by motor proteins such as chromokinesin Kid (also known as KIF22). Kid generates a polar ejection force and contributes to alignment of the chromosome arms during prometaphase and metaphase, whereas during anaphase, Kid contributes to chromosome compaction. How Kid is regulated and how this regulation is important for chromosome dynamics remains unclear. Here, we address these questions by expressing mutant forms of Kid in Kid-deficient cells. We demonstrate that Cdk1-mediated phosphorylation of Thr463 is required to generate the polar ejection force on Kid-binding chromosomes, whereas dephosphorylation of Thr463 prevents generation of the ejection force on such chromosomes. In addition to activation of the second microtubule-binding domain through dephosphorylation of Thr463, the coiled-coil domain is essential in suspending generation of the polar ejection force, preventing separated chromosomes from becoming recongressed during anaphase. We propose that phosphorylation of Thr463 switches the mitotic chromosome movement from an anti-poleward direction to a poleward direction by converting the Kid functional mode from polar-ejection-force-ON to -OFF during the metaphase-anaphase transition, and that both the second microtubule-binding domain and the coiled-coil domain are involved in this switching process.

Caveolin-1 in extracellular matrix vesicles secreted from osteoblasts.

Caveolin-1 is an essential and signature protein of caveolae, which are small invaginations of the plasma membrane enriched in cholesterol and sphingolipids. Although high levels of expression of caveolin-1 have been demonstrated in osteoblasts as well as endothelial cells, fibroblasts, and muscular cells, the role of caveolin-1 in osteoblasts has not been clarified. Here, we show that caveolin-1 is secreted from osteoblasts in the form of matrix vesicles; extracellular vesicles released from the plasma membrane of osteoblasts. In this study, caveolae and matrix vesicles were similarly enriched in cholesterol and sphingomyelin in fractions isolated from mineralizing MC3T3-E1 cells. Interestingly, in the MC3T3-E1 cells caveolin-1 was enriched in the matrix vesicle fraction as well as the caveolar membrane fraction, and the amount of caveolin-1 in the matrix vesicle fraction increased as differentiation progressed. Localization of caveolin-1 in matrix vesicles was also confirmed in murine tibia. Furthermore, overexpression of caveolin-1 enhanced matrix calcification in MC3T3-E1 cells, whereas knockdown of caveolin-1 diminished it. These results suggest that secreted caveolin-1 as a component of matrix vesicles may play an important role in osteoblast calcification.

Sox6 overexpression causes cellular aggregation and the neuronal differentiation of P19 embryonic carcinoma cells in the absence of retinoic acid.

The Sox6 gene is a member of the Sox gene family that encodes transcription factors. Previous studies have suggested that Sox6 plays an important role in the development of the central nervous system. Aggregation of embryonic carcinoma P19 cells with retinoic acid (RA) results in the development of neurons, glia and fibroblast-like cells. In this report, we have shown that Sox6 mRNA increased rapidly in P19 cells during RA induction and then decreased during the differentiation of P19 into neuronal cells. To explore the possible roles of Sox6 during this process, stably Sox6-overexpressing P19 cell lines (P19[Sox6]) were established. These P19[Sox6] had acquired both characteristics of the wild-type P19 induced by RA. First, P19[Sox6] cells showed a marked cellular aggregation in the absence of RA. Second, P19[Sox6] could differentiate into microtubule-associated protein 2 (MAP2)-expressing neuronal cells in the absence of RA. Sox6 expression could cause the activation of endogenous genes including the neuronal transcription factor Mash-1, the neuronal development-related gene Wnt-1, the neuron-specific cell adhesion molecule N-cadherin, and the neuron-specific protein MAP2, resulting in neurogenesis. Moreover, E-cadherin, a major cell adhesion molecule of wild-type P19, was strongly induced by Sox6, resulting in cellular aggregation without RA. Thus Sox6 may play a critical role in cellular aggregation and neuronal differentiation of P19 cells.