Biomedical subjects

Takashi Shimizu

Publications and source records attributed to Takashi Shimizu.

At least 19 recordsLinked to original sources

PubMed2026

Characterization of the oral microbiota and antimicrobial resistance genes in shelter dogs in Japan.

Companion animals can serve as reservoirs of antimicrobial resistance genes and zoonotic microorganisms, yet information on shelter dogs remains limited. This study characterized the oral microbiota and screened for antimicrobial resistance genes in shelter dogs in Japan. Oral swabs were collected from 81 dogs, microbial genomic DNA was extracted, bacterial communities were profiled by 16S rRNA gene amplicon sequencing, and antimicrobial resistance genes were screened by PCR. We detected genes conferring resistance to several antimicrobial classes, including β-lactams, tetracyclines, macrolide-lincosamide-streptogramin B, phenicols, and sulfonamides. cfxA was detected in all 81 samples, followed by sul1 (66/81), tet(M) and sul2 (65/81), floR (39/81), mecA (17/81), and erm(B) (15/81). We identified potentially pathogenic genera including Capnocytophaga, Pasteurella, Fusobacterium, Campylobacter and Corynebacterium. Microbiome analysis revealed that at the phylum level, Pseudomonadota and Bacteroidota were the most dominant, while Porphyromonas, Frederiksenia and Moraxella were the most prevalent genera. Our findings highlight that (i) the oral microbiota of shelter dogs broadly resembles that reported in companion dogs and (ii) shelter dogs represent an overlooked reservoir of clinically relevant antimicrobial resistance genes and potentially zoonotic bacteria. Therefore, it is necessary to include shelter animals in antimicrobial resistance surveillance programs to capture any potential gaps in the antimicrobial resistance prevalence in companion animals and prevent dissemination of resistant bacteria to humans following adoption of shelter dogs and cats.

antimicrobial resistance gene↗

PubMed2007

Initial specification of the epibranchial placode in zebrafish embryos depends on the fibroblast growth factor signal.

In vertebrates, cranial sensory ganglia are mainly derived from ectodermal placodes, which are focal thickenings at characteristic positions in the embryonic head. Here, we provide the first description of the early development of the epibranchial placode in zebrafish embryos using sox3 as a molecular marker. By the one-somite stage, we saw a pair of single sox3-expressing domains appear lateral to the future hindbrain. The sox3 domain, which is referred to here as the early lateral placode, is segregated during the early phase of segmentation to form a pax2a-positive medial area and a pax2a-negative lateral area. The medial area subsequently developed to form the otic placode, while the lateral area was further segregated along the anteroposterior axis, giving rise to four sox3-positive subdomains by 26 hr postfertilization. Given their spatial relationship with the expression of the markers for the epibranchial ganglion, as well as their positions and temporal changes, we propose that these four domains correspond to the facial, glossopharyngeal, vagal, and posterior lateral line placodes in an anterior-to-posterior order. The expression of sox3 in the early lateral placode was absent in mutants lacking functional fgf8, while implantation of fibroblast growth factor (FGF) beads restored the sox3 expression. Using SU5402, which inhibits the FGF signal, we were able to demonstrate that formation of both the early lateral domains and later epibranchial placodes depends on the FGF signal operating at the beginning of somitogenesis. Together, these data provide evidence for the essential role of FGF signals in the development of the epibranchial placodes.

Animals↗

PubMed2006

Role of the hyaluronan receptor CD44 during porcine oocyte maturation.

Previous our studies have shown that CD44, the principal receptor for hyaluronan, is present on cumulus cells during oocyte maturation. Although hyaluronan-CD44 interaction has been implicated in cumulus expansion and/or oocyte maturation, the full significance of CD44 remains unknown. The objective of the present study was to further investigate the role of CD44 in cumulus expansion and oocyte maturation in pigs. We demonstrate here in that CD44 has a key role in oocyte maturation but not in cumulus expansion. Previous studies have reported the physiological significance of cumulus expansion in oocyte maturation. However, our results suggest that cumulus expansion is a necessary condition for oocyte maturation, but that it is not sufficient on its own. Furthermore, western blot analysis demonstrated that the CD44 of the in vitro-matured cumulus-oocyte complexes (COCs) had a larger molecular weight and more terminal sialic acid, which has been proven to inhibit the hyaluronan-binding ability of the receptor, than the CD44 of the in vivo-matured COCs, indicating that the hyaluronan-CD44 interactions during in vitro maturation might be insufficient compared with those in vivo. The insufficient interactions of hyaluronan-CD44 during in vitro maturation may cause the inferior capacity of fertilization and development of oocytes matured in vitro.

Animals↗

PubMed2006

Changes in plasma metabolic hormone concentrations during the ovarian cycles of Japanese black and holstein cattle.

The aim of the present study was to investigate the changing profiles of plasma metabolic hormones during the ovarian cycles of beef and dairy cattle. We used 16 non-pregnant, non-lactating Japanese Black beef cattle (6 heifers and 10 cows; parity=2.3 +/- 0.8) and 12 multiparous Holstein dairy cows (parity=3.0 +/- 0.3). Blood samples for hormonal analysis (growth hormone, GH; insulin-like growth factor-I, IGF-1; insulin; and progesterone, P4) were obtained twice weekly for 40 days before artificial insemination for Japanese Black cattle and from 50 to 100 days postpartum for Holstein cows. Luteal phases were considered normal if the P4 concentrations for at least 3 time points over the course of 7 days remained above 1 ng/ml and at least 2 of the time points were above 2 ng/ml. The patterns of the ovarian cycles were classified into two types (normal or abnormal, such as having prolonged luteal phase and cessation of cyclicity) on the basis of the plasma P4 profiles. The plasma concentrations of IGF-1 in both breeds increased transiently during the preovulatory period when the P4 levels were low and decreased to lower levels during the luteal phase when the P4 levels were high. The plasma concentrations of insulin in the 3(rd) week of normal ovarian cycles when the plasma P4 concentration dropped to less than 1 ng/ml were higher than those at other time points in the Japanese Black cattle, but not in the Holstein cows. The plasma concentrations of GH did not change during the ovarian cycle in either breed. In conclusion, the present study indicates that the plasma IGF-1 concentration increases during the follicular phase (low P4 levels) and decreases during the luteal phase (high P4 levels) in non-lactating Japanese Black and lactating Holstein cattle. The results suggest that ovarian steroids, rather than nutrient status, may be related to the cyclic changes in IGF-1 secretion from the liver in cattle.

Animals↗

PubMed2006

Cdx-Hox code controls competence for responding to Fgfs and retinoic acid in zebrafish neural tissue.

Fibroblast growth factor (Fgf) and retinoic acid (RA) signals control the formation and anteroposterior patterning of posterior hindbrain. They are also involved in development processes in other regions of the embryo. Therefore, responsiveness to Fgf and RA signals must be controlled in a context-dependent manner. Inhibiting the caudal-related genes cdx1a and cdx4 in zebrafish embryos caused ectopic expression of genes that are normally expressed in the posterior hindbrain and anterior spinal cord, and ectopic formation of the hindbrain motor and commissure neurons in the posteriormost neural tissue. Combinational marker analyses suggest mirror-image duplication in the Cdx1a/4-defective embryos, and cell transplantation analysis further revealed that Cdx1a and Cdx4 repress a posterior hindbrain-specific gene expression cell-autonomously in the posterior neural tissue. Expression of fgfs and retinaldehyde dehydrogenase 2 suggested that in the Cdx1a/4-defective embryos, the Fgf and RA signaling activities overlap in the posterior body and display opposing gradients, compared with those in the hindbrain region. We found that Fgf and RA signals were required for ectopic expression. Expression of the posterior hox genes hoxb7a, hoxa9a or hoxb9a, which function downstream of Cdx1a/4, or activator fusion genes of hoxa9a or hoxb9a (VP16-hoxa9a, VP16-hoxb9a) suppressed this loss-of-function phenotype. These data suggest that Cdx suppresses the posterior hindbrain fate through regulation of the posterior hox genes; the posterior Hox proteins function as transcriptional activators and indirectly repress the ectopic expression of the posterior hindbrain genes in the posterior neural tissue. Our results indicate that the Cdx-Hox code modifies tissue competence to respond to Fgfs and RA in neural tissue.

Animals↗

PubMed2006

Serratia marcescens serralysin induces inflammatory responses through protease-activated receptor 2.

The Serratia marcescens-derived protease serralysin is considered to play an important role in the pathogenesis of infection. Protease-activated receptor 2 (PAR-2) is activated by trypsin and also several other trypsin-like serine proteases, leading to the modulation of inflammatory and immune responses. However, little is known about the activation of PAR-2 by bacterial proteases and its roles in bacterial infection. In this study, we investigated whether S. marcescens serralysin activates host inflammatory responses through PAR-2. Our results demonstrated that serralysin induces interleukin-6 (IL-6) and IL-8 mRNA expression in a human lung squamous cell carcinoma, EBC-l cells. In addition, serralysin activated activator protein 1 (AP-1)-, CCAAT/enhancer-binding protein (C/EBP)-, and nuclear factor-kappaB (NF-kappaB)-driven promoters in EBC-1 cells. An electrophoretic mobility shift assay showed that serralysin activates the binding of AP-1, C/EBPbeta, and NF-kappaB in the cells. Inactivation of serralysin resulted in the failure of transactivation of AP-1-, C/EBP-, and NF-kappaB-driven promoters in the cells. Furthermore, serralysin activated AP-1-, C/EBP-, and NF-kappaB-driven promoters via PAR-2 in HeLa cells. PAR-2 antagonist peptides decreased serralysin-induced transactivation of AP-1-, C/EBP-, and NF-kappaB-driven promoters in EBC-1 cells. Considered together, these results suggest that serralysin requires PAR-2 to activate the critical transcription factors AP-1, C/EBPbeta, and NF-kappaB for host inflammatory responses.

CCAAT-Enhancer-Binding Proteins↗

PubMed2006

Differential effect of follicle-stimulating hormone and estradiol on expressions of vascular endothelial growth factor (VEGF) 120, VEGF164 and their receptors in bovine granulosa cells.

Vascular endothelial growth factor (VEGF) isoforms (VEGF 120 and VEGF 164) secreted by granulosa cells are involved in thecal angiogenesis during follicular development in the bovine ovary. However, whether the transcript of the VEGF120 and VEGF164 isoforms differs during follicular development in the ovary is still unknown. We first examined the gene expression of VEGF120, VEGF164, fms-like tyrosine kinase (Flt-1), and fetal liver kinase (Flk-1) in the granulosa cells (GCs) and theca cells (TCs) of pre-selection and post-selection follicles (PRF and POF respectively) from the bovine ovary. Then we examined the effects of FSH and estradiol (E2) on these factors in cultured bovine GCs. Messenger RNA (mRNA) expression was quantified using real-time PCR methods. The concentrations of E2 and P4 in the follicular fluid (FF) of the PRF and POF were estimated using an enzyme immunoassay (EIA). The concentrations of E2 and P4 in the FF were significantly higher in the POF than in the PRF. The ratio of E2/P4 in PRF and POF was 0.37 and 3.8, respectively. The expression levels of the VEGF120, VEGF164, and Flk-1 mRNAs in the GCs of POF with high E2 concentration were higher than those of PRF. The levels of the Flt-1 and Flk-1 mRNAs in the TCs were not different between PRF and POF. Since E2 in the FF of the POF used in the present study was high compared with the PRF, we examined the effects of E2 and FSH on the expression of the above genes using cultured GCs. Expression of VEGF120 mRNA was induced by a low concentration (1 ng/ml) of E2, whereas the levels of VEGF164 and Flk-1 mRNAs were not affected by E2. FSH stimulated the expression of the VEGF isoforms and Flk-1 genes. Moreover, the expression of those genes was enhanced when low E2 (1 ng/ml) was added to FSH. In conclusion, our data indicates that the VEGF isoforms have a follicle stage-dependent expression pattern. Thus, our results suggest that the expression of VEGF isoforms may be associated with characterization of the preovulatory phenotype during follicle development in the bovine ovary.

Animals↗

PubMed2006

Preliminary report of treatment with oral contraceptive pills for intermenstrual vaginal bleeding secondary to a cesarean section scar.

Uterine scar has been reported as a possible cause of intermenstrual bleeding in women with previous cesareans. We evaluated the effectiveness of combined hormonal therapy (estrogen and progesterone tablets containing 0.5 mg of norgestrel and 0.05 mg of ethynyl estradiol) in patients with recurring vaginal bleeding after cesarean section. Several cycles of the hormonal therapy eliminated the problem of abnormal vaginal bleeding, and the patients were satisfied with the treatment.

Adult↗

PubMed2006

Antimicrobial activity of inducible human beta defensin-2 against Mycoplasma pneumoniae.

Defensins in innate immunity are known to play critical roles to protect the host from infection by invasive microbes, including Gram-positive and -negative bacteria. However, little is known about the interactions between defensins and mycoplasmas. Human beta defensin (hBD)-2 and hBD-3, but not hBD-1, were found to exert strikingly antimicrobial activity against Mycoplasma pneumoniae. To elucidate the role of defensins in M. pneumoniae infection, a human pulmonary squamous cell line EBC-1 was stimulated with M. pneumoniae and interleukin (IL)-1beta. hBD-2 was markedly upregulated by IL-1beta as well as M. pneumoniae, but neither hBD-1 nor hBD-3 was apparently upregulated. Thus, the results suggest that inducible hBD-2 would play a critical role in the protection of M. pneumoniae infection.

Cells, Cultured↗

PubMed2006

Follicle-stimulating hormone (FSH) stimulates the expression of Pin1, a peptidyl-prolyl isomerase, in the bovine granulosa cells.

A peptidyl-prolyl isomerase, Pin 1, has been shown to play a role in the regulation of cell cycle progression, both in vitro and in vivo. However, the involvement of Pin 1 during follicular development is not well understood. The aim of this study was first to investigate the expression of Pin 1 mRNA in the granulosa and theca cells of the follicle at different developmental stages of follicles in the bovine ovary, and second, to examine the effects of follicle-stimulating hormone (FSH) and estradiol (E2) on the expression of Pin 1 in the cultured bovine granulosa cells. Follicles were classified into four groups based on the diameter (dominant follicles >8.5mm in diameter, subordinate follicles <8.5mm in diameter) and the relative levels of E2 and progesterone (P4) (E2:P4>1, estrogen active; E2:P4<1, estrogen inactive): i.e. preovulatory dominant follicles (POFs); E2 active dominant follicles (EADs); E2 inactive dominant follicles (EIDs); small follicles (SFs). The expression of the Pin 1 gene was significantly increased in the granulosa cells of EADs as compared with those of other follicles, whereas its expression in theca cells did not differ among follicles at different developmental stages. The concentration of 5 ng/ml FSH alone and the combination of 1 ng/ml E2 and 5 ng/ml FSH stimulated the expression of the Pin 1 gene in bovine granulosa cells. Our data provide the first evidence that Pin 1 expression in the granulosa cells but not the theca cells changes during follicular development, and that FSH stimulate the expression of the Pin 1 gene. These results suggest that Pin 1 regulates the timing of cell proliferation and may act as an intracellular signal responder in the granulosa cells during bovine follicle development.

Animals↗

PubMed2006

A novel cell division factor from tobacco 2B-13 cells that induced cell division in auxin-starved tobacco BY-2 cells.

Effects of auxin as plant hormones are widespread; in fact in almost all aspects of plant growth and development auxin plays a pivotal role. Although auxin is required for propagating cell division in plant cells, its effect upon cell division is least understood. If auxin is depleted from the culture medium, cultured cells cease to divide. It has been demonstrated in this context that the addition of auxin to auxin-starved nondividing tobacco BY-2 cells induced semisynchronous cell division. On the other hand, there are some cell lines, named habituated cells, that can grow without auxin. The cause and reason for the habituated cells have not been clarified. A habituated cell line named 2B-13 is derived from the tobacco BY-2 cell line, which has been most intensively studied among plant cell lines. When we tried to find the difference between two cell lines of BY-2 and 2B-13 cells, we found that the addition of culture filtrated from the auxin-habituated 2B-13 cells induced semisynchronous cell division in auxin-starved BY-2 cells. The cell division factor (CDF) that is responsible for inducing cell division in auxin-starved BY-2 cells was purified to near-homogeneity by sequential passage through a hydroxyapatite column, a ConA Sepharose column and a Sephadex gel filtration column. The resulting purified fraction appeared as a single band of high molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels by silver staining and was able to induce cell division in auxin-starved BY-2 cells. Identification of the protein by MALD-TOF-MS/MS revealed that it is structurally related to P-glycoprotein from Gossypioides kirkii, which belongs to ATP-binding cassette (ABC)-transporters. The significance of CDF as a possible ABC-transporter is discussed in relationship to auxin-autotrophic growth and auxin-signaling pathway.

Amino Acid Sequence↗

PubMed2006

A wide-range phylogenetic analysis of Zic proteins: implications for correlations between protein structure conservation and body plan complexity.

We compared Zic homologues from a wide range of animals. Striking conservation was found in the zinc finger domains, in which an exon-intron boundary has been kept in all bilateralians but not cnidarians, suggesting that all of the bilateralian Zic genes are derived from a single gene in a bilateralian ancestor. There were additional conserved amino acid sequences, ZOC and ZF-NC. Combined analysis of the zinc finger, ZOC, and ZF-NC revealed the presence of two classes of Zic, based on the degree of protein structure conservation. The "conserved" class includes Zic proteins from the Arthropoda, Mollusca, Annelida, Echinodermata, and Chordata (vertebrates and cephalochordates), whereas the "diverged" class contains those from the Platyhelminthes, Cnidaria, Nematoda, and Chordata (urochordates). The result indicates that the ancestral bilateralian Zic protein had already acquired an entire set of conserved domains, but that this was lost and diverged in the platyhelminthes, nematodes, and urochordates.

Amino Acid Sequence↗

PubMed2006

Coiled coil in the stalk region of ncd motor protein is nonlocally sustained.

The dimeric structure of kinesin superfamily proteins plays an important role in their motile functions and characteristics. In this study, the coiled-coil-forming property of the stalk region (192-346) of Drosophila ncd, a C-terminal kinesin motor protein, was investigated by synthesizing various peptide fragments. The alpha helicity of a set of 46-residue peptides spanning the stalk region appeared too low to form a coiled-coil dimer, probably because of insufficient continuity of the hydrophobic residues at (a and d) core positions in amphipathic heptad repeats. On the other hand, several peptides with leucine residues introduced at core positions or with extensional sequences with high alpha helicity had an advantage in coiled-coil formation. When we analyzed the thermal and urea-induced unfolding of these dimeric peptides, we identified four domains having a relatively high potential to form coiled coils. Among them, three domains on the C-terminal side of the stalk region, i.e., (252-272), (276-330), and (336-346), were in the same heptad frame, although these potential coiled-coil domains were not self-sustaining individually. This is in sharp contrast to the fragment of human kinesin, (332-369), which has an extremely high tendency toward coiled-coil formation. One of the possible triggers for coiled-coil formation of the ncd stalk region may be the interaction between the motor domain and the C-terminal part of the stalk as previously revealed by X-ray crystallography. The residues, S331 and R335, seem to act as a breaking point for alpha-helix continuity. This would make the region (336-346), as the head-stalk joint, more flexible such as seen with a plus-end-directed kinesin, if this region had no interaction with the motor domain. These characteristic differences between ncd and kinesin suggest that the nonlocally sustained coiled coil of ncd is one of the factors important for minus-end-directed motility.

Amino Acid Sequence↗

PubMed2006

Embryonic expression of a decapentaplegic gene in the oligochaete annelid Tubifex tubifex.

We have cloned and characterized the expression of a decapentaplegic homologue (designated Ttu-dpp) from the oligochaete annelid Tubifex tubifex. RT-PCR analysis and in situ hybridization revealed that Ttu-dpp begins to be expressed around the time of the onset of ectodermal germ band (GB) elongation (i.e., the onset of gastrulation). At this time, Ttu-dpp expression is detected in the anteriormost part of the GBs. As development proceeds and the GBs elongate, the domain of Ttu-dpp-expressing cells extends posteriorly. Then Ttu-dpp-expressing cells within the GB are divided into two groups: one group occurs along the ventral midline and coincides with the domain of ventral ganglia; the other is located more dorsally. The latter group of Ttu-dpp-expressing cells subsequently undergoes dorsalward expansion, which results in the formation of a lateral stripe of cells in every segment except the first (i.e., segment I). In embryos that undergo body elongation (that is one of the last morphogenetic movements occurring prior to hatchout), Ttu-dpp expression in the lateral region is confined to setal sacs, which are arranged in the same transverse plane around the periphery of each segment (except segment I).

Amino Acid Sequence↗

PubMed2006

Sizzled controls dorso-ventral polarity by repressing cleavage of the Chordin protein.

The Bone morphogenetic protein (Bmp) signalling gradient has a major function in the formation of the dorso-ventral axis. The zebrafish ventralized mutant, ogon, encodes Secreted Frizzled (Sizzled). sizzled is ventrally expressed in a Bmp-dependent manner and is required for the suppression of Bmp signalling on the ventral side of zebrafish embryos. However, it remains unclear how Sizzled inhibits Bmp signalling and controls ventro-lateral cell fate. We found that Sizzled stabilizes Chordin, a Bmp antagonist, by binding and inhibiting the Tolloid-family metalloproteinase, Bmp1a, which cleaves and inactivates Chordin. The cysteine-rich domain of Sizzled is required for inhibition of Bmp1a activity. Loss of both Bmp1a and Tolloid-like1 (Tll1; another Tolloid-family metalloproteinase) function leads to a complete suppression and reversal of the ogon mutant phenotype. These results indicate that Sizzled represses the activities of Tolloid-family proteins, thereby creating the Chordin-Bmp activity gradient along the dorso-ventral axis. Here, we describe a previously unrecognized role for a secreted Frizzled-related protein.

Animals↗

PubMed2006

Involvement of the bone morphogenetic protein/receptor system during follicle development in the bovine ovary: Hormonal regulation of the expression of bone morphogenetic protein 7 (BMP-7) and its receptors (ActRII and ALK-2).

Bone morphogenetic proteins (BMPs) are crucial factors in follicular growth and development. Among the BMP ligands, BMP-7 which use ActRII as their type II receptor, strongly bind to ALK-2 as their type I receptor. However, whether their receptors are expressed and the regulatory mechanisms controlling their expression during the process of bovine follicle development are still unknown. The aim of the present study was to clarify the involvement of the receptor system for BMP-7 in follicular selection by examining the effects of follicle-stimulating hormone (FSH) and estradiol (E2) on the regulation of ActRII and ALK-2 mRNA expression in bovine granulosa cells (GCs). To observe mRNA expression, follicles were obtained from heifers and GCs were classified into two groups: pre-selection follicles (PRF; follicles with an average diameter of 7 mm and low E2) and post-selection follicles (POF; follicles with an average diameter of 15 mm and high E2). The theca cell (TC) layer and GCs were harvested from aspirated follicles. For in vitro studies, GCs were obtained from bovine follicles of 4-7 mm diameter and cultured in Dulbecco's modified Eagle's/F12 (DMEM/F-12) medium with 10% fetal calf serum for 24h. The medium was then replaced with serum-free DMEM/F-12 supplemented with different doses of E2 (1, 10,100 ng/ml), FSH (1, 5, 10 ng/ml) or combinations of 1 ng/ml of E2 with different FSH doses (1, 5, 10 ng/ml). Total RNA was extracted from GCs and the mRNA expression of ActRII and ALK-2 was estimated by the quantitative PCR method using LightCycler. The expression of BMP-7 mRNA in TCs did not differ between the PRF and POF. ActRII and ALK-2 expression was detected in GCs from bovine antral follicles and was higher in the GCs of POF than in those of PRF, while the expression of the ActRII and ALK-2 genes in the TCs was not different between PRF and POF. Treatment of GCs with E2 (10 ng/ml) alone increased the expression of both ActRII and ALK-2 mRNAs, whereas FSH alone had no effect. However, ActRII and ALK-2 mRNA levels were up-regulated by the combination of E2 (1 ng/ml) and FSH (5 ng/ml). The results of the present study provide the first evidence that FSH and E2 regulate the expression of the ActRII and ALK-2 genes in bovine GCs. Thus, our data suggest that the BMP7/ActRII/ALK-2 system may be critically involved in the process of selection of bovine follicles.

Activin Receptors, Type I↗

PubMed2006

Sodium butyrate up-regulates cathelicidin gene expression via activator protein-1 and histone acetylation at the promoter region in a human lung epithelial cell line, EBC-1.

The antimicrobial protein cathelicidin is considered to play an important role in the defense mechanisms against bacterial infection. Recent studies show that sodium butyrate induces cathelicidin gene expression in human colonic, gastric and hepatic cells. However, little is known about the precise regulatory mechanisms underlying sodium butyrate-induced cathelicidin gene expression. In this study, we examined the regulatory mechanisms involved in sodium butyrate-induced cathelicidin gene expression using a human lung epithelial cell line, EBC-1. Our results indicate that sodium butyrate induces both cathelicidin mRNA and protein expression. Moreover, deletion or mutation of a putative activator protein-1 (AP-1) binding site in the cathelicidin gene promoter abrogated the response to sodium butyrate stimulation. Three different mitogen-activated protein (MAP) kinase inhibitors suppressed sodium butyrate-induced transactivation of the cathelicidin promoter. Electrophoretic mobility shift assays (EMSA) showed that nuclear extracts prepared from sodium butyrate-stimulated EBC-1 cells generated specific binding to probe including a putative AP-1 binding site in the cathelicidin gene promoter. Furthermore, chromatin immunoprecipitation (ChIP) assays demonstrated that sodium butyrate augmented histone acetylation of the cathelicidin promoter in EBC-1 cells. Therefore, these results indicate that AP-1 and histone acetylation of the cathelicidin promoter play a critical role in the regulation of inducible cathelicidin gene expression in EBC-1 cells stimulated with sodium butyrate.

Acetylation↗

PubMed2006

Expression of fibroblast growth factor 1 (FGF1) and FGF7 in mature follicles during the periovulatory period after GnRH in the cow.

The aim of this study was to evaluate the expression pattern of mRNA for fibroblast growth factor 1 (FGF1), FGF7, and their receptor variants (FGFR2IIIb) in time-defined follicle classes before LH surge, between LH surge and ovulation, and in the early corpus luteum (CL) in the cow. The ovaries were collected by transvaginal ovariectomy (n=5 cows/group), and the follicles (n=5, one follicle/cow) were classified into the following groups: before GnRH administration (before LH surge); 3-5 h after GnRH (during LH surge); 10 h after GnRH; 20 h after GnRH; 25 h after GnRH (periovulation), and early CL (Days 2-3). The mRNA expression was analyzed by quantitative real-time PCR (RotorGene 3000). The mRNA expression of FGF1 showed no significant differences in the follicle groups examined, but increased significantly at the early CL phase. A transient increase in FGF7 mRNA expression was observed 3-5 h after GnRH and again in the early CL phase. In contrast, the expression of FGFR2IIIb was constant throughout the period from the final growth of the follicle to early CL formation. The results of this study suggest that FGF1 and FGF7 may be involved differently in the process of follicle maturation and CL formation, which is strongly dependent on angiogenesis.

Animals↗