Porcine Placenta Research Articles

DNA methylation-mediated silencing of FLT1 in parthenogenetic porcine placentas

Studies show that perturbed expression of vascular endothelial growth factor (VEGF) family genes is related to abnormal development of parthenogenetic (PA) placenta. In this study, the methylation status of VEGF family genes were compared between PA and normal placentas using bisulfite sequencing PCR (BSP). Results showed no significant difference in the methylation of VEGF-A differentially methylated region (DMR), placental growth factor (PIGF) DMR, and kinase insert domain receptor (KDR) DMR, whereas FMS-like tyrosine kinase 1 (FLT1) DMR was hypermethylated in PA placentas. These results suggested that abnormal methylation of FLT1 DMR might trigger the developmental failure of porcine PA placentas.

Oral Administration of Glycine and Leucine Dipeptides Improves Skin Hydration and Elasticity in UVB-Irradiated Hairless Mice.

Placenta is a special organ that contains many nutrients such as growth factors, minerals, and bioactive peptides. Dipeptides of glycine and leucine are major components of porcine placenta extracts (PPE) that has been used as an alternative of human placenta extracts. In this study, we investigated whether major peptides of PPE, Glycyl-L-Leucine (Gly-Leu), L-Leucyl-Glycine (Leu-Gly), and L-Leucyl-L-Leucine (Leu-Leu), affect skin hydration and elasticity in vitro and in vivo. We found that Gly-Leu and Leu-Gly dipeptides induced the expression of transglutaminase 1 in normal human epidermal keratinocytes (NHEKs) whereas Leu-Leu dipeptides did not. Treatment with Gly-Leu or Leu-Gly significantly increased hyaluronan (HA) synthesis in NHEKs and the upregulation of hyaluronan synthase 2 (HAS2) mRNA level was confirmed. In addition, elastase activity was inhibited in NHEKs treated with Gly-Leu or Leu-Gly dipeptides. Oral administration of Gly-Leu or Leu-Gly dipeptides increased skin hydration and elasticity in UVB-irradiated hairless mice. The significant upregulation of HA in UVB-irradiated hairless mice was observed in response to oral administration of Gly-Leu or Leu-Gly. These results suggest that the major dipeptides of porcine placenta, Gly-Leu and Leu-Gly, are potentially active ingredients for skin moisturization formulations.

Peroxisome proliferator‑activated receptor γ mediates porcine placental angiogenesis through hypoxia inducible factor‑, vascular endothelial growth factor‑ and angiopoietin‑mediated signaling.

Peroxisome proliferator-activated receptor (PPAR) γ has been reported to be implicated in placentation in mice. Previous studies have demonstrated that PPARγ is also expressed in porcine placenta, primarily localized in vascular endothelial cells (VECs). The present study aimed to investigate the roles of PPARγ during porcine placental angiogenesis and examine the molecular mechanisms involved in its actions. VECs were incubated with the PPARγ agonist rosiglitazone and the antagonist T0070907, and their angiogenic potential was evaluated using cellular impedance, wound healing and tube formation assays. Reverse transcription-quantitative polymerase chain reaction was used to assess the mRNA expression levels of angiogenic factors, including hypoxia-inducible factors (HIFs), vascular endothelial growth factor (VEGF) isoforms, VEGF receptors (VEGFRs) and angiopoietins (Angs). The results demonstrated that the adhesive, proliferative and migratory capabilities of VECs were potentiated by rosiglitazone and suppressed by T0070907. Notably, tube formation was invariably promoted during PPARγ activation and blockade. The mRNA expression levels of HIF1α, HIF2α, VEGFR2, VEGF188 and Ang-1 were revealed to be upregulated following treatment of VECs with rosiglitazone, whereas they were downregulated following treatment with T0070907. However, the mRNA expression levels of placental growth factor and VEGF120 were consistently downregulated following PPARγ activation and blockade, whereas VEGF164 mRNA levels remained unaltered. The results of the present study suggested that PPARγ may mediate porcine placental angiogenesis, by interfering with HIF-, VEGF- and angiopoietin-mediated signaling pathways.

Identification of appropriate reference genes for qPCR analyses of placental expression of SLC7A3 and induction of SLC5A1 in porcine endometrium

IntroductionEndometria and placentae undergo developmental changes that affect the stability of genes used as references for normalization of qPCR data. We identified genes that are stable within the porcine endometrium and placenta throughout pregnancy, and elucidated the temporal/spatial mRNA localization of the glucose and arginine transporters, solute carrier family (SLC) 5A1 and SLC7A3, respectively. Materials and MethodsqPCR was performed for 10 genes within porcine endometria from Days 5, 11, and 15 of the estrous cycle and 11, 15, 25, 40, 60, and 85 of pregnancy; and chorioallantois from Days 30, 35, 45, 50, 60, and 85. Gene stability was analyzed using GeNorm and NormFinder algorithms. qPCR and in situ hybridization determined temporal/spatial localization of SLC5A1 and SLC7A3 at the uterine-placental interface. ResultsThe geometric mean of TATA-binding protein (TBP), hypoxanthine phosphoribosyl transferase 1 (HPRT1), and tubulin alpha 1B (TUBA1B) provides acceptable reference values for porcine placenta. The geometric mean of TBP, beta actin (ACTB), and succinate dehydrogenase complex subunit A flavoprotein (SDHA) is acceptable for endometria. SLC5A1 is induced by estrogen in endometrial luminal epithelium (LE) on Days 12 and 13 of pregnancy. SLC7A3 is expressed in the chorion. Discussion and ConclusionUsing appropriate reference genes resulted in complementary results between qPCR and in situ hybridization techniques for SLC5A1 and SLC7A3 mRNAs. SLC5A1 is induced in uterine LE by estrogen of trophectoderm origin when the blastocyst is free-floating and dependent on glucose from the endometrium, and SLC7A3 is expressed by the established placenta to support fetal growth.

Cellular Localization and Regulation of Expression of the PLET1 Gene in Porcine Placenta.

The placenta expressed transcript 1 (PLET1) gene, which is expressed in placentas of pigs and mice, has been found to have a potential role in trophoblast cell fate decision in mice. Results of this study showed that the porcine PLET1 mRNA and protein were expressed exclusively in trophoblast cells on Days 15, 26, 50, and 95 of gestation (gestation length in the pig is 114 days), indicating that the PLET1 could be a useful marker for porcine trophoblast cells. Additionally, PLET1 protein was found to be redistributed from cytoplasm to the apical side of trophoblast cells as gestation progresses, which suggests a role of PLET1 in the establishment of a stable trophoblast and endometrial epithelial layers. In addition, two transcripts that differ in the 3′ UTR length but encode identical protein were identified to be generated by the alternative cleavage and polyadenylation (APA), and the expression of PLET1-L transcript was significantly upregulated in porcine placentas as gestation progresses. Furthermore, we demonstrated the interaction between the miR-365-3p and PLET1 gene using luciferase assay system. Our findings imply an important role of PLET1 in the placental development in pigs.

Anti-fatigue effect by active dipeptides of fermented porcine placenta through inhibiting the inflammatory and oxidative reactions.

Recently, we reported an anti-fatigue effect of fermented porcine placenta (FPP). Glycine-leucine (GL) and leucine-glycine (LG) dipeptides are main peptides of FPP. However, the therapeutic effects and underlying mechanisms of GL and LG dipeptides on fatigue are still unclear. Herein, we examined the anti-fatigue properties of GL and LG dipeptides using RAW264.7 macrophages and forced swimming test (FST) animal model. Our data revealed that lipopolysaccharide (LPS)-induced interleukin (IL)-1β, tumor necrosis factor-α, and IL-6 productions were markedly inhibited by GL or LG in RAW264.7 macrophages without inducing cytotoxicity. LPS-enhanced nitric oxide (NO) production and inducible nitric oxide synthase expression were inhibited by GL or LG, whereas superoxide dismutase (SOD) activities were significantly enhanced by GL or LG in LPS-stimulated RAW264.7 macrophages. The present study also figured out that these effects of GL and LG were mediated by blockade of caspase-1 and nuclear factor-κB activation. In FST-induced fatigue mouse model, the mice which received the GL or LG for 21days showed significant decreases of IL-1β, IL-6, and NO serum levels. Treatment with GL or LG significantly enhanced levels of SOD and glycogen and significantly lowered levels of lactate dehydrogenase, aspartate transaminase, and alanine transaminase. Taken together, our results indicated that GL and LG dipeptides, active components of FPP, should be considered as candidate of anti-fatigue agents.

Porcine placenta hydrolysates enhance osteoblast differentiation through their antioxidant activity and effects on ER stress

BackgroundOsteoporosis is a disease characterized by decreased bone strength, decreased bone mass, and bone deterioration. Oxidative damage is an important contributor to functional changes in the development of osteoporosis. Here we found that porcine placenta hydrolysates (PPHs) protect MC3T3-E1 osteoblastic cells against hydrogen peroxide (H2O2)-induced oxidative damage.MethodsIn vitro cell viability was determined using trypan blue dye exclusion. ER stress and apoptosis were evaluated using immunoblotting and a commercially available caspase kit. ALP, osteocalcin, Runx2, and osterix expression levels were evaluated by RT-PCR using isolated RNA. ROS, NADPH oxidase, and SOD activity levels were also measured.ResultsWe investigated the mechanisms underlying PPH-mediated inhibition of H2O2-induced ER stress and ROS production. PPHs also regulated osteoblast differentiation via the upregulation of alkaline phosphatase (ALP) expression in MC3T3-E1 osteoblastic cells. Also, treatment with PPHs enhanced the transcription of osteocalcin, Runx2, and osterix. These effects were all associated with the antioxidant actions of PPHs. Moreover, PPHs reversed the decrease in SOD activity, decreased ROS release, and inhibited NADPH oxidase activity in H2O2-treated MC3T3-E1 osteoblastic cells.ConclusionsPPHs protect cells against H2O2-induced cell damage when ER stress is involved. In addition, PPHs enhance osteoblast differentiation. This enhancement likely explains the regulatory effect of PPHs on bone metabolism disturbances, i.e. PPHs control ER stress and the related ROS production in osteoblasts.

Porcine placenta hydrolysates regulate calcium disturbance in MC3T3-E1 osteoblastic cells.

BackgroundIn bone metabolism, Ca2+ disturbance and oxidative damage are the main biochemical factors related to pathology. Osteoblasts are bone-forming cells that also control bone endocrinology. Endocrine hormones and proteins are matured, folded, and secreted in the endoplasmic reticulum (ER). ER stress has emerged as a new pathological mechanism to explain bone disturbance. Here we studied the role of porcine placenta hydrolysates (PPHs) in the regulation of ER stress.MethodsCell viability was determined in vitro using trypan blue dye exclusion. ER stress and apoptosis were evaluated using immunoblotting and a caspase kit. The fluorescent Ca2+-binding dye Fura-2/AM was used to measure changes in intracellular Ca2+ ([Ca2+]i). ROS levels, NADPH oxidase activity, and superoxide dismutase (SOD) activity were also measured.ResultsPPHs protected MC3T3-E1 osteoblastic cells against thapsigargin (Tg)-induced ER stress. Moreover, PPHs regulated caspase-12 and −3 activities, thereby protecting against cell death, and also regulated Tg-induced Ca2+ release. The Ca2+ chelator BAPT/AM also regulated caspase-12 and −3 activities and prevented Ca2 stress-induced cell death. In the presence of PPHs or BAPTA/AM, Ca2+-related ROS were also regulated, as demonstrated by alterations in NADPH oxidase and SOD activity.ConclusionsPPHs appear to regulate bone metabolism disturbance by controlling Ca2+ concentrations, and thus ER stress and ROS, in osteoblasts cultured in vitro.Electronic supplementary materialThe online version of this article (doi:10.1186/s12906-016-1202-1) contains supplementary material, which is available to authorized users.

Effect of fermented porcine placenta on physical fatigue in mice.

The fatigue spreads among the people who live under stressful life and brings about a negative impact on physical function. Here we evaluated the anti-fatigue effects of fermented porcine placenta (FPP) and main constituents, lysine (Lys) and leucine (Leu) with treadmill stress test and forced swimming test (FST) in animal models. The mice were administrated with FPP, Lys, and Leu for 21 days. After treadmill exercise, FPP, Lys, and Leu significantly reduced fatigue-related biochemical parameters, including lactate, lactate dehydrogenase, glucose, creatine kinase, urea nitrogen, cortisol, and pro-inflammatory cytokines, whereas superoxide dismutase activity and glycogen levels were significantly increased by FPP, Lys, and Leu. In the FST, FPP, Lys, and Leu significantly decreased immobility times and up-regulated brain-derived neurotrophic factor expression in brain. Furthermore, FPP, Lys, and Leu significantly decreased production of tumor necrosis factor-α, interleukin (IL)-6, IL-1β, and IL-4 through blockade of caspase-1/nuclear factor-κB pathway in stimulated splenocytes. In addition, FPP, Lys, and Leu significantly promoted proliferation of splenocytes. In conclusion, these findings suggest the potential of FPP as a novel functional food for the regulation of fatigue.

Expression of progesterone receptor in the porcine uterus and placenta throughout gestation: correlation with expression of uteroferrin and osteopontin

Progesterone (P4) stimulates production and secretion of histotroph, a mixture of hormones, growth factors, nutrients, and other substances required for growth and development of the conceptus (embryo or fetus and placental membranes). Progesterone acts through the progesterone receptor (PGR); however, there is a gap in our understanding of P4 during pregnancy because PGR have not been localized in the uteri and placentae of pigs beyond day 18. Therefore, we determined endometrial expression of PGR messenger RNA (mRNA) and localized PGR protein in uterine and placental tissues throughout the estrous cycle and through day 85 of pregnancy in pigs. Further, 2 components of histotroph, tartrate-resistant acid phosphatase 5 (ACP5; uteroferrin) and secreted phosphoprotein 1 (SPP1; osteopontin) proteins, were localized in relation to PGR during pregnancy. Endometrial expression of PGR mRNA was highest at day 5 of the estrous cycle, decreased between days 5 and 11 of both the estrous cycle and pregnancy, and then increased between days 11 and 17 of the estrous cycle (P < 0.01), but decreased from days 13 to 40 of pregnancy (P < 0.01). Progesterone receptor protein localized to uterine stroma and myometrium throughout all days of the estrous cycle and pregnancy. PGR were expressed by uterine luminal epithelium (LE) between days 5 and 11 of the estrous cycle and pregnancy, then PGR became undetectable in LE through day 85 of pregnancy. During the estrous cycle, PGR were downregulated in LE between days 11 and 15, but expression returned to LE on day 17. All uterine glandular epithelial (GE) cells expressed PGR from days 5 to 11 of the estrous cycle and pregnancy, but expression decreased in the superficial GE by day 12. Expression of PGR in GE continued to decrease between days 25 and 85 of pregnancy; however, a few glands near the myometrium and in close proximity to areolae maintained expression of PGR protein. Acid phosphatase 5 protein was detected in the GE from days 12 to 85 of gestation and in areolae. Secreted phosphoprotein 1 protein was detected in uterine LE in apposition to interareolar, but not areolar areas of the chorioallantois on all days examined, and in uterine GE between days 35 and 85 of gestation. Interestingly, uterine GE cells adjacent to areolae expressed PGR, but not ACP5 or SPP1, suggesting these are excretory ducts involved in the passage, but not secretion, of histotroph into the areolar lumen and highlighting that P4 does not stimulate histotroph production in epithelial cells that express PGR.

Anti-fatigue effect of fermented porcine placenta through the regulation of fatigue-associated inflammatory cytokines

Fatigue is a common complaint and affects the quality of life in modern people. Physical stress may induce activation of certain immune cells. Fermented porcine placenta (FPP) has been used to alleviate fatigue. Inflammatory cytokines are produced by physical stress and results in symptoms of fatigue. However, the role of FPP on fatigue-associated inflammatory cytokine production has not been elucidated yet. Thus, we estimated the anti-fatigue effect of FPP and its active components, leucine (Leu) and lysine (Lys) in activated RAW264.7 macrophages and forced swimming test (FST) fatigue animal model. Pretreatment with FPP, Leu, or Lys significantly inhibited the lipopolysaccharide (LPS)-induced tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 production without inducing cytotoxicity on LPS-stimulated RAW264.7 macrophages. FPP, Leu, or Lys inhibited the production of nitric oxide and downregulated the expression of inducible nitric oxide synthase on LPS-stimulated RAW264.7 macrophages. Furthermore, caspase-1 activities increased by LPS were significantly reduced by FPP, Leu, or Lys. In the FST, inflammatory cytokine levels of the mice administrated with FPP, Lys, and Leu were significantly reduced compared with the control group at 21 days. Collectively, these results show that anti-fatigue effect of FPP and its active components, Leu and Lys might be derived from the down-regulating of inflammatory mediators.

Uterine and placenta characteristics during early vascular development in the pig from day 22 to 42 of gestation

Insufficient placenta development is one of the primary causes of fetal death and reduced fetal growth after 35 days of gestation. Between day 22 and 42 the placenta consists of a central highly vascular placenta (HVP), adjacent to the fetus, a less vascular placenta (LVP), on either side of the fetus, and necrotic tips (NT). The objective of this study was to comprehensively evaluate uterine–placenta characteristics during early gestation in the gilt and determine time points and physiological changes. Gilts (n=25) were artificially inseminated at first detection of estrus (day 0) and 24h later, and harvested at 22, 27, 32, 37 or 42 days of gestation. Litter size, 12.1±3.4, was similar for all days of gestation. Fetal and placenta weight increased with day of gestation. The greatest increase in placenta weight occurred between 37 and 42 days of gestation. The LVP zones had no measurable fold formation until day 27. Necrotic tips became apparent after 27 days of gestation. Unoccupied areas of the uterus developed folds with changes in endometrial cell size and morphology from day 32 to 42 of gestation. Limited changes occurred in either fetal growth or placenta weight from day 27 through 32 of gestation; however, significant morphological changes occur at the maternal–fetal interface, demonstrating the dynamic architecture of the developing porcine placenta during early gestation. This work establishes fundamental time points in placenta development corresponding to fetal growth and microfold formation that may influence fetal growth and impact fetal survival.

FcRn Expression on Placenta and Fetal Jejunum during Early, Mid-, and Late Gestation in Minipigs.

Developmental toxicity testing of therapeutic antibodies is most often conducted in nonhuman primates owing to lack of cross-reactivity in other species. Minipigs may show cross-reactivity for some humanized antibodies but have not been used for developmental toxicity testing due to an assumed lack of embryo-fetal exposure. Unlike in humans, maternal IgGs do not cross the porcine placenta to reach the fetus. Some humanized IgGs, however, have a higher affinity for the neonatal Fc receptor (FcRn) and are more likely than endogenous antibodies to cross the placenta of animals. The major site of prenatal IgG transfer is the placenta, though FcRn in fetal intestine could also uptake maternal IgGs from swallowed amniotic fluid. Using immunohistochemistry andin situhybridization in this experiment, FcRn was found in minipig placenta and fetal intestine during early, mid-, and late gestation. To date, however, fetal exposure to maternally administered IgGs has never been demonstrated in the minipig.

Proteomic analysis of reproduction proteins involved in litter size from porcine placenta.

A gel-free and label-free quantitative proteomic approach based on a spectral counting strategy was performed to discover prolificacy-related proteins. Soluble proteins of porcine placenta from small litter size group (SLSG) and large litter size group (LLSG) were extracted and subsequently applied to in-solution tryptic digestion followed by liquid chromatography-tandem mass spectrometry analysis. Six and thirteen proteins were highly expressed in SLSG and LLSG, respectively. Of the dominantly expressed proteins, we chose prolificacy-related proteins such as puromycin-sensitive aminopeptidase (PSA) and retinol-binding protein 4 (RBP4). Western blot analysis confirmed that the processed form (70 kDa) of PSA was more expressed and RBP4 (23 kDa) was dominantly expressed in LLSG. These results indicate that PSA and RBP4 are representative proteins involved in porcine fertility traits, and this finding may help to increase litter size of pigs.

Protective effect of porcine placenta in a menopausal ovariectomized mouse

Menopause is a significant physiological phase that occurs as women's ovaries stop producing ovum and the production of estrogen declines. Human placenta and some amino acids are known to improve menopausal symptoms. In this study, we investigated that porcine placenta extract (PPE) and arginine (Arg), a main amino acid of PPE, would have estrogenic activities in ovariectomized (OVX) mice as a menopause mouse model, human breast cancer cell line (MCF-7) cells, and human osteoblast cell line (MG-63) cells. PPE or Arg significantly inhibited the body weight and increased the vagina weight compared to the OVX mice. PPE or Arg ameliorated the vaginal atrophy in the OVX mice. The levels of 17β-estradiol and the activities of alkaline phosphatase (ALP) were significantly increased by PPE or Arg in the serum of OVX mice. Trabecular bone parameters such as bone mineral density and porosity were also improved by PPE or Arg in the OVX mice. In the MCF-7 and MG-63 cells, PPE or Arg significantly increased the cell proliferation, estrogen receptor β mRNA expression, and estrogen-response elements luciferase activity. Finally, PPE or Arg increased the activations of ALP and extracellular signal-regulated kinase 1/2 in the MG-63 cells. These results indicate that PPE or Arg would have estrogenic and osteoblastic activity. Therefore, PPE or Arg may be useful as new pharmacological tools for treating menopausal symptoms including osteoporosis. Free Korean abstract: A Korean translation of this abstract is freely available at http://www.reproduction-online.org/content/150/3/173/suppl/DC1.

FcRn expression on placenta and fetal jejunum during early, mid and late gestation in minipigs

Developmental toxicity testing of therapeutic antibodies is most often conducted in nonhuman primates owing to lack of cross-reactivity in other species. Minipigs may show cross-reactivity for some humanized antibodies but have not been used for developmental toxicity testing due to an assumed lack of embryo-fetal exposure. Unlike in humans, maternal IgGs do not cross the porcine placenta to reach the fetus. Some humanized IgGs, however, have a higher affinity for the neonatal Fc receptor (FcRn) and are more likely than endogenous antibodies to cross the placenta of animals. The major site of prenatal IgG transfer is the placenta, though FcRn in fetal intestine could also uptake maternal IgGs from swallowed amniotic fluid. Using immunohistochemistry andin situhybridization in this experiment, FcRn was found in minipig placenta and fetal intestine during early, mid-, and late gestation. To date, however, fetal exposure to maternally administered IgGs has never been demonstrated in the minipig.

The Expression Pattern of MicroRNAs and the Associated Pathways Involved in the Development of Porcine Placental Folds That Contribute to the Expansion of the Exchange Surface Area.

The development of the microscopically folded structure of the diffuse epitheliochorial placenta in pigs is important because it expands the surface area for maternal-fetal exchange, resulting in an increase in placental efficiency. To better understand the regulatory mechanisms involved in this process, we characterized miRNA expression profiles in porcine placentas during the initiation and establishment of placental fold development. A total of 42 miRNAs were found to be differentially expressed, and their putative target genes were predicted using four target prediction programs. Following a comparative analysis with published gene expression pattern data obtained from porcine placentas in the corresponding stages of placental fold development, only those genes that were negatively correlated with miRNA expression were retained for further function and pathway enrichment analysis. The results showed that the up-regulated miRNAs were associated mainly with extracellular matrix remodeling and tissue morphogenesis, while the down-regulated miRNAs were related to cell proliferation and signal transduction. Furthermore, we provide evidence that miR-130b may facilitate the expression of HPSE, which has been reported to be a regulator of the folding of the pig placenta, by suppressing the expression of PPARG. In addition, we also reveal that the miRNA-target pairs expressed in the pig placenta may trigger the degradation of the stromal matrix and basement membrane (miR-29a-COL1A2, COL3A1, and LAMC1) and regulate trophoblast epithelial cell adherens junctions (the miR-200 family and miR-205-ZEB2-CDH1) and proliferation (miR-17-92 cluster-HBP1 and ULK1). Taken together, these results indicate that miRNAs and related pathways may have potential roles in porcine placental fold development.

Enhanced Anti-inflammatory Effects of γ-irradiated Pig Placenta Extracts.

Porcine placenta extract (PPE) is known to possess anti-inflammatory properties owing to its high concentration of bioactive substances. However, the need to eliminate blood-borne infectious agents while maintaining biological efficacy raises concerns about the optimal method for sterilizing PPE. Therefore, the objective of this study was to compare the effects of the standard pressurized heat (autoclaving) method of sterilization with γ-irradiation on the anti-inflammatory effects of PPE. The anti-inflammatory actions of these two preparations of PPE were evaluated by measuring their inhibitory effects on the production of NO, the expression of iNOS protein, and the expression of iNOS, COX2, TNF-α, IL-1β, and IL-6 mRNA in lipopolysaccharide-stimulated RAW 264.7 cells. Compared with autoclaved PPE, γ-irradiated PPE showed significantly greater inhibition of NO production and iNOS protein expression, and produced a greater reduction in the expression of iNOS, COX2, TNF-α, IL-1β, and IL-6 mRNA. These results provide evidence that the sterilization process is crucial in determining the biological activity of PPE, especially its anti-inflammatory activity. Collectively, our data suggest that γ-irradiated PPE acts at the transcriptional level to effectively and potently suppresses the production of NO and the expression of pro-inflammatory cytokines.

Effects of Porcine Placenta Extract Ingestion on Ultraviolet B-induced Skin Damage in Hairless Mice

The aim of our study was to evaluate the potential benefits of an oral supplement containing porcine placenta extract (PPE) on skin parameters related to cutaneous physiology and aging. PPEs were administered orally to hairless mice for 12 wk. The effects of oral PPE administration on skin water-holding capacity and Transepidermal Water Loss (TEWL) were similar to those of oral collagen (HYCPU2) administered as a positive control. Magnified photographs and replica images showed a reduction in UVB-induced wrinkle formation after collagen and PPE treatments. PPE treatments ameliorated the thicker skin surface that results from UVB exposure, based on a histological examination of skin tissue. The groups that were orally administered PPE (0.05%, OL; 0.1%, OH group) showed significantly reduced Matrix Metaloproteinase-2 (MMP-2) mRNA expression levels compared with the UVB control (Con), by 33.5% and 35.2%, respectively. The mRNA expression of another collagen-degrading protein, MMP-9, was also significantly lower in the groups that received oral administration of PPE (especially in the OH group) than in the control group. Additionally, oral administration of PPE significantly upregulated tissue inhibitor of metalloproteinase-1 (TIMP-1) and -2 mRNA expression levels compared with expression levels in the control group (p<0.05). This indicates that orally administered PPE activated the expression of Timp-1 and -2, inhibitors of MMP, which is responsible for collagen degradation in skin. Taken together, we propose that long-term oral administration of PPE might have a beneficial effect with respect to skin photo-aging.

Protective effect of porcine placenta in a menopausal ovariectomized mouse.

Menopause is a significant physiological phase that occurs as women's ovaries stop producing ovum and the production of estrogen declines. Human placenta and some amino acids are known to improve menopausal symptoms. In this study, we investigated that porcine placenta extract (PPE) and arginine (Arg), a main amino acid of PPE, would have estrogenic activities in ovariectomized (OVX) mice as a menopause mouse model, human breast cancer cell line (MCF-7) cells, and human osteoblast cell line (MG-63) cells. PPE or Arg significantly inhibited the body weight and increased the vagina weight compared to the OVX mice. PPE or Arg ameliorated the vaginal atrophy in the OVX mice. The levels of 17β-estradiol and the activities of alkaline phosphatase (ALP) were significantly increased by PPE or Arg in the serum of OVX mice. Trabecular bone parameters such as bone mineral density and porosity were also improved by PPE or Arg in the OVX mice. In the MCF-7 and MG-63 cells, PPE or Arg significantly increased the cell proliferation, estrogen receptor β mRNA expression, and estrogen-response elements luciferase activity. Finally, PPE or Arg increased the activations of ALP and extracellular signal-regulated kinase 1/2 in the MG-63 cells. These results indicate that PPE or Arg would have estrogenic and osteoblastic activity. Therefore, PPE or Arg may be useful as new pharmacological tools for treating menopausal symptoms including osteoporosis. Free Korean abstract: A Korean translation of this abstract is freely available at http://www.reproduction-online.org/content/150/3/173/suppl/DC1.