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1.
Animals (Basel) ; 11(11)2021 Nov 09.
Article in English | MEDLINE | ID: mdl-34827927

ABSTRACT

Epithelial barrier function in the mammary gland acts as a forefront of the defense mechanism against mastitis, which is widespread and a major disorder in dairy production. Chemerin is a chemoattractant protein with potent antimicrobial ability, but its role in the mammary gland remains unelucidated. The aim of this study was to determine the function of chemerin in mammary epithelial tissue of dairy cows in lactation or dry-off periods. Mammary epithelial cells produced chemerin protein, and secreted chemerin was detected in milk samples. Chemerin treatment promoted the proliferation of cultured bovine mammary epithelial cells and protected the integrity of the epithelial cell layer from hydrogen peroxide (H2O2)-induced damage. Meanwhile, chemerin levels were higher in mammary tissue with mastitis. Tumor necrosis factor alpha (TNF-α) strongly upregulated the expression of the chemerin-coding gene (RARRES2) in mammary epithelial cells. Therefore, chemerin was suggested to support mammary epithelial cell growth and epithelial barrier function and to be regulated by inflammatory stimuli. Our results may indicate chemerin as a novel therapeutic target for diseases in the bovine mammary gland.

2.
Anim Sci J ; 85(10): 910-4, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24841561

ABSTRACT

We analyzed the urinary excretion of glucose and N-acetyl-ß-D-glucosaminidase (NAG) in six okapis (Okapia johnstoni) in captivity to investigate the cause of their urinary sugar excretion. The urinary glucose-positive okapi had significantly higher urinary NAG indices than the urinary glucose-negative okapi. There was also a positive correlation between urinary glucose levels and urinary NAG indices. These results suggest that the proximal tubular function of the glycosuric okapi may have been obstructed, which impaired glucose reabsorption.


Subject(s)
Acetylglucosaminidase/urine , Glycosuria/veterinary , Ruminants/urine , Animals , Animals, Zoo , Female , Glycosuria/urine , Male , Ruminants/classification
3.
Anim Sci J ; 83(12): 788-95, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23216544

ABSTRACT

Although our previous report demonstrated that adiponectin and AdipoR1 gene expressions changed among different lactation stages in the bovine mammary gland, its in vivo kinetics remain unclear in ruminant animals. In this study, we investigated the changes in circulating concentrations of adiponectin, as well as other metabolic hormones and metabolites, (i) during the periparturient period and (ii) among different lactation stages, in Holstein dairy cows. In experiment 1, serum adiponectin concentrations increased after parturition. Serum insulin concentrations were lower in the postpartum than prepartum period, whereas serum growth hormone (GH) concentrations increased in the postpartum period. Serum nonesterified fatty acids (NEFA) levels were increased during the postpartum period and were dependent on the parity. In experiment 2, there was no significant difference in plasma adiponectin concentrations among lactational stages. Plasma insulin concentrations tended to be lower in early lactation while plasma GH levels tended to be higher. Plasma NEFA concentrations were significantly lower in mid- and late-lactation stages than non-lactation stages. These findings indicate that elevation of serum adiponectin might be involved in energy metabolism just around parturition, and might exert its action through regulation of receptor expression levels in target tissues in each lactational stage in Holstein dairy cows.


Subject(s)
Adiponectin/blood , Cattle/physiology , Energy Metabolism/physiology , Lactation/physiology , Parturition/physiology , Animals , Fatty Acids, Nonesterified/blood , Female , Growth Hormone/blood , Insulin/blood , Lactation/blood , Parturition/blood
4.
Anim Sci J ; 83(3): 263-7, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22435632

ABSTRACT

Accumulating data suggest a relationship between chemerin and energy metabolism. Our group previously described gene cloning, expression analysis and the regulatory mechanism of chemerin and its own receptor in mice and cattle. The objective of the present study was to investigate the physiological effect of chemerin on endocrine changes and energy metabolism in sheep using a biologically stable chemerin analog. The chemerin analog was intravenously administrated (100 or 500 µg/head) to sheep, and plasma insulin and metabolites (glucose, nonesterified fatty acids (NEFA), triglyceride, total cholesterol and high-density lipoprotein (HDL) cholesterol) were analyzed. The chemerin analog dramatically increased the insulin levels, and glucose levels were decreased. NEFA levels were slightly decreased at 20 min but then increased gradually from 60 to 180 min after analog administration. In addition, injection of the chemerin analog immediately increased triglyceride and total cholesterol but not HDL levels. These results suggested that chemerin analog regulated insulin secretion related to glucose metabolism and the release of triglycerides in sheep in vivo. This study provides new information about endocrine and metabolic changes in response to chemerin in sheep.


Subject(s)
Chemokines/physiology , Energy Metabolism/physiology , Sheep/metabolism , Animals , Blood Glucose/metabolism , Cholesterol/blood , Fatty Acids, Nonesterified/blood , Insulin/metabolism , Insulin Secretion , Lipoproteins, HDL/blood , Triglycerides/blood
5.
Anim Sci J ; 82(1): 99-106, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21269367

ABSTRACT

Although the functions of adiponectin, a differentiated adipocyte-derived hormone, in regulating glucose and fatty acid metabolism are regulated by two subtypes of adiponectin receptors (AdipoRs; AdipoR1 and AdipoR2), those in ruminants remain unclear. Therefore we examined the messenger RNA (mRNA) expression levels of adiponectin and its receptors in various bovine tissues and mammary glands among different lactation stages, and the effects of lactogenic hormones (insulin, dexamethasone and prolactin) and growth hormone (GH) on mRNA expression of the AdipoRs in cultured bovine mammary epithelial cells (BMEC). AdipoRs mRNAs were widely expressed in various bovine tissues, but adiponectin mRNA expression was significantly higher in adipose tissue than in other tissues. In the mammary gland, although adiponectin mRNA expression was significantly decreased at lactation, AdipoR1 mRNA expression was significantly higher at peak lactation than at the dry-off stage. In BMEC, lactogenic hormones and GH upregulated AdipoR2 mRNA expression but did not change that of AdipoR1. In conclusion, adiponectin and its receptor mRNA were expressed in various bovine tissues and the adiponectin mRNA level was decreased during lactation. These results suggest that adiponectin and its receptors ware changed in mammary glands by lactation and that AdipoRs mRNA expression was regulated by different pathways in BMEC.


Subject(s)
Adiponectin/genetics , Adiponectin/metabolism , Epithelial Cells/metabolism , Gene Expression Regulation , Growth Hormone/pharmacology , Mammary Glands, Human/cytology , Mammary Glands, Human/metabolism , Prolactin/pharmacology , Animals , Cattle , Cells, Cultured , Dexamethasone/pharmacology , Female , Growth Hormone/physiology , Humans , Insulin/pharmacology , Insulin/physiology , Lactation/genetics , Lactation/physiology , Prolactin/physiology , RNA, Messenger/metabolism , Receptors, Adiponectin/genetics , Receptors, Adiponectin/metabolism , Theophylline/analogs & derivatives , Up-Regulation
6.
Comp Biochem Physiol B Biochem Mol Biol ; 149(2): 285-92, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17977041

ABSTRACT

To understand the relationship between intramuscular adipogenesis in the pig and the supply fatty acids, we established a clonal porcine intramuscular preadipocyte (PIP) line from the marbling muscle tissue of female Duroc pig. Confluent PIP cells exhibited a fibroblastic appearance. Their adipogenic ability was investigated using confluent PIP cells after exchanging growth medium for adipogenic medium containing 50 ng/mL insulin, 0.25 microM dexamethasone, 2 mM octanoate, and 200 microM oleate. Appropriate concentrations of octanoate and oleate for the induction of adipogenesis were determined from the ability of cells to accumulate lipid and the toxicity of fatty acids. When cells were cultured in differentiation medium for 8 days, large numbers of lipid droplets were observed in differentiated PIP cells, and their cytosolic TG content increased in a time-dependent manner. While oleate only induced the expression of PPARgamma mRNA, but not that of C/EBPalpha, octanoate significantly induced the expression of both PPARgamma and C/EBPalpha mRNA. Octanoate and oleate accelerated the inducing effect of insulin and dexamethasone on the expression of aP2 mRNA. These results indicate that a combination of octanoate and oleate synergistically induced PIP adipogenesis, and that the stimulation of octanoate was essential to the trigger for the adipogenesis in PIP cells.


Subject(s)
Adipocytes, White/drug effects , Caprylates/pharmacology , Cell Differentiation/drug effects , Oleic Acid/pharmacology , Adipocytes, White/cytology , Adipocytes, White/metabolism , Adipocytes, White/physiology , Adipogenesis/drug effects , Adipogenesis/genetics , Animals , Biomarkers/metabolism , Cells, Cultured , Drug Combinations , Female , Gene Expression Regulation/drug effects , Muscle, Skeletal/chemistry , Muscle, Skeletal/drug effects , Muscle, Skeletal/physiology , Sus scrofa
7.
Domest Anim Endocrinol ; 32(4): 260-72, 2007 May.
Article in English | MEDLINE | ID: mdl-16698222

ABSTRACT

Growth hormone (GH) plays a specific role to inhibit apoptosis in the bovine mammary gland through the insulin-like growth factor (IGF)-I system, however, the mechanism of GH action is poorly understood. In this study, we show that GH dramatically inhibits the expression of IGFBP-5, and GH along with IGF-I enhanced the phosphorylation of Akt through the reduction of IGF binding protein (IGFBP)-5. To determine how GH affects Akt through IGF-I in bovine mammary epithelial cells (BMECs), we examined the phosphorylation of Akt in GH treated BMECs and found that IGF-I induced phosphorylation of Akt was significantly enhanced by the treatment with GH. We demonstrated that GH reduces mRNA and protein expression of IGFBP-5 in BMECs, but it does not affect the expression of IGFBP-3. To determine that the enhanced effect of the Akt phosphorylation by the treatment of GH is due to the inhibition of the expression of IGFBP-5, we examined the effect of IGFBP-3 and -5 on the phosphorylation of Akt through IGF-I in the GH-treated BMECs. The phosphorylation of Akt was inhibited in a dose-dependent manner when IGFBP-5 was added at varying concentrations and was also inhibited in the presence of IGFBP-3. The results of this study suggest that GH plays an important role on mammary gland involution in bovine mammary epithelial cells.


Subject(s)
Epithelial Cells/metabolism , Growth Hormone/physiology , Insulin-Like Growth Factor Binding Protein 5/metabolism , Insulin-Like Growth Factor I/physiology , Proto-Oncogene Proteins c-akt/metabolism , Animals , Cattle , Cell Survival/physiology , Female , Gene Expression Regulation/physiology , Lactation/metabolism , Mammary Glands, Animal/cytology , Mammary Glands, Animal/growth & development , Mammary Glands, Animal/metabolism , Organ Size , Phosphorylation , Signal Transduction/physiology
8.
Domest Anim Endocrinol ; 31(1): 88-96, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16198527

ABSTRACT

Leptin mRNA is expressed in not only adipocytes but also mammary epithelial cells and leptin protein is present in milk. Although milk leptin is thought to influence metabolism or the immune system in neonates, there is little information about the regulation of leptin expression in mammary epithelial cells. We examined the effect of growth hormone (GH) and/or lactogenic hormone complex (DIP; dexamethasone, insulin and prolactin) on leptin mRNA expression in mammary epithelial cells. We used a bovine mammary epithelial cell (BMEC) clonal line, which was established from a 26-day pregnant Holstein heifer. We confirmed that the mRNA was expressed in BMECs and the expression was significantly reduced by GH and/or DIP, when the cells were cultured on both plastic plates and cell culture inserts at days 2 and 7 after stimulation with lactogenic hormones. GH and/or DIP significantly increased level of alpha-casein mRNA in BMECs after 7 days on the cell culture inserts, but no mRNA expression was detected at day 2. GH and DIP significantly stimulated the secretion of alpha-casein from BMEC on cell culture inserts at 3.5 and 7 days. However, neither alpha-casein mRNA expression nor secretion was observed in the BMECs cultured on plastic dishes, even in the presence of GH or/and DIP. These results indicate that GH and DIP can directly reduce leptin mRNA expression in both undifferentiated and functionally differentiated bovine mammary epithelial cell.


Subject(s)
Cattle/metabolism , Growth Hormone/pharmacology , Leptin/biosynthesis , Mammary Glands, Animal/metabolism , Prolactin/pharmacology , RNA, Messenger/biosynthesis , Animals , Caseins/genetics , Caseins/metabolism , Cell Line , Dexamethasone/pharmacology , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , Gene Expression Regulation/drug effects , Insulin/pharmacology , Leptin/genetics , Mammary Glands, Animal/cytology , Mammary Glands, Animal/drug effects , Pregnancy , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction/veterinary
9.
J Dairy Res ; 72(3): 264-70, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16174355

ABSTRACT

To study the effect of growth hormone (GH) on the functions of mammary epithelia, we examined the effect of GH on the synthesis and secretion of alpha-casein in a bovine mammary epithelial cell (BMEC) clonal line, which was established from a 26-d-pregnant Holstein heifer. GH receptors (GHR) were observed in the BMEC on the membrane as well as in the cytoplasm. After BMEC were plated onto cell culture inserts, GH stimulated alpha-casein release in both the presence and absence of the lactogenic hormone complex, which included dexamethasone, insulin and prolactin (DIP). DIP enhanced the effect of GH on alpha-casein release. Although alpha(s1-) casein mRNA expression was not detected in untreated control cells, its expression was observed in BMEC in response to the GH, DIP and GH + DIP treatments. Expression was greater for GH and GH + DIP than for just DIP. Expression of GHR mRNA was increased by DIP treatment, while the mRNA expression was little changed by GH treatment. We conclude that GH acts on BMEC and induces the expression of both the alpha-casein gene and protein. GHR gene expression was shown to be regulated by DIP and GHR. GHR may be involved in a synergic effect between GH and DIP on casein secretion. These results suggest that GH, in addition to its widely accepted homeorhetic role in vivo, also can act on the mammary parenchyma, and that the effects of GH on mammary epithelial cells could partly account for the clear galactopoietic effect of recombinant bovine GH seen in lactating dairy cows.


Subject(s)
Caseins/biosynthesis , Caseins/metabolism , Cattle/physiology , Growth Hormone/pharmacology , Mammary Glands, Animal/metabolism , Animals , Caseins/genetics , Cell Line , Dexamethasone/pharmacology , Epithelial Cells/chemistry , Epithelial Cells/drug effects , Epithelial Cells/physiology , Female , Gene Expression/drug effects , Insulin/pharmacology , Lactation , Mammary Glands, Animal/drug effects , Pregnancy , Prolactin/pharmacology , RNA, Messenger/analysis , Receptors, Somatotropin/analysis , Receptors, Somatotropin/genetics , Recombinant Proteins/pharmacology , Reverse Transcriptase Polymerase Chain Reaction
10.
J Dairy Res ; 71(4): 398-404, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15605705

ABSTRACT

Mammary epithelial cells, which express and secrete leptin into milk, accumulate triacylglycerol (TAG). We examined effects on the accumulation of cytosolic TAG of addition of short- (acetate and butyrate) or medium- (octanoate) chain fatty acids to the medium bathing bovine mammary epithelial cells (bMEC). Octanoate stimulated the accumulation of TAG in a concentration-dependent manner from 1 to 10 mM and increased lipid droplet formation and mRNA expression of CD36 (a fatty acid translocase). Additionally, expression of a peroxisome proliferator activated receptor (PPAR) gamma 2 protein that is a lipid-activated transcription factor, was increased by the addition of acetate or octanoate. However, leptin mRNA expression was significantly reduced by addition of acetate or butyrate. Both short- and medium-chain fatty acids inhibited acetyl coenzyme A carboxylase (ACC) activities, which is pivotal in lipid synthesis, but elevated expression of uncoupling protein 2 (UCP2) mRNA, which is important in energy expenditure. These results suggest that octanoate induces cytosolic TAG accumulation and the formation of lipid droplets, and that acetate and butyrate inhibit leptin expression and lipid synthesis in bMEC.


Subject(s)
Acetyl-CoA Carboxylase/antagonists & inhibitors , CD36 Antigens/genetics , Caprylates/pharmacology , Cattle , Mammary Glands, Animal/drug effects , Triglycerides/metabolism , Animals , Cells, Cultured , Cytosol/metabolism , Enzyme Inhibitors/pharmacology , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , Gene Expression/drug effects , Ion Channels , Leptin/genetics , Mammary Glands, Animal/metabolism , Membrane Transport Proteins/genetics , Mitochondrial Proteins/genetics , PPAR gamma/genetics , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , Uncoupling Protein 2
11.
Article in English | MEDLINE | ID: mdl-12547264

ABSTRACT

Little attention has been paid to carbonic anhydrase VI (CA VI), a secretory type isozyme, in the bovine mammary gland, although the gland is an important exocrine gland and CA VI is known to localize in exocrine glands such as salivary and lacrimal glands in various animal species. In the present study mRNA expression and protein localization of CA VI in isolated gland tissues and in cloned epithelial cells from the mammary gland of Holstein cows (Bos taurus) were observed by reverse transcript polymerase chain reaction and immunocytochemistry. Also, changes of CA VI concentrations in milk were measured for 2 months postpartum by an enzyme-linked immunosorbent assay. CA VI gene expression was detected in the gland tissues and epithelial cells, and CA VI protein was localized in the cytoplasm of the epithelial cells. Colostrum contained the highest concentration of CA VI protein (100 ng/ml), decreasing in an exponential manner (P<0.001). We conclude that bovine mammary epithelial cells synthesize and secrete CA VI in colostrum at higher concentration than in normal milk, implying its role to compensate for low CA VI secretion in neonatal calves.


Subject(s)
Carbonic Anhydrases/metabolism , Cattle/physiology , Lactation , Mammary Glands, Animal/enzymology , Protein Subunits/metabolism , Animals , Carbonic Anhydrases/analysis , Carbonic Anhydrases/genetics , Clone Cells , Colostrum/chemistry , DNA, Complementary/metabolism , Enzyme-Linked Immunosorbent Assay , Epithelial Cells/enzymology , Female , Immunohistochemistry , Mammary Glands, Animal/cytology , Milk/chemistry , Osmolar Concentration , Parotid Gland/enzymology , Protein Subunits/analysis , Protein Subunits/genetics , Reverse Transcriptase Polymerase Chain Reaction , Tissue Distribution
12.
J Dairy Res ; 69(3): 345-55, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12369405

ABSTRACT

The aim of the study was to establish in vitro a bovine mammary epithelial cell (MEC) clone, able to respond to mitogenic growth factors and to lactogenic hormones. Mammary tissue from a 200-d pregnant Holstein cow was used as a source of MEC, from which a clone was established through a process of limiting dilution. When plated on plastic, the cells assumed a monolayer, cobblestone, epithelial-like morphology, with close contact between cells. Inclusion of IGF-1 and EGF in the media significantly increased the number of cells 5 d after plating. All cells stained strongly for cytokeratin and moderately for vimentin at young and old passage stages, indicating the epithelial nature of this cell clone. When the cells were plated at a high density on a thin layer of a commercial extracellular matrix preparation (Matrigel), lobular, alveoli-like structures developed within approximately 5 d, with a clearly visible lumen. When cells were plated onto Matrigel in differentiation media (containing lactogenic hormones), detectable quantities of alpha-casein were present in the media and particularly on the lumen side of the structures. Omission of one of the lactogenic hormones (insulin, prolactin or hydrocortisone) reduced alpha-casein release to the limit of detection of the assay used. Lactoferrin was also produced when the cells were plated on Matrigel, again principally on the lumen side of the lobules, though this was independent of the lactogenic hormones. By passage 40, the cells had senesced, and it was not possible to induce alpha-casein or lactoferrin production. This study notes the establishment of a functional bovine mammary epithelial cell clone, which is responsive to mitogenic and lactogenic hormones and an extracellular matrix.


Subject(s)
Cell Differentiation/physiology , Epithelial Cells/physiology , Mammary Glands, Animal/cytology , Animals , Caseins/biosynthesis , Cattle , Cell Differentiation/drug effects , Cell Division , Cells, Cultured , Cellular Senescence/physiology , Clone Cells , Collagen , Culture Media , Cytoskeletal Proteins/analysis , Drug Combinations , Enzyme-Linked Immunosorbent Assay/veterinary , Epithelial Cells/cytology , Extracellular Matrix/physiology , Female , Fluorescent Antibody Technique/veterinary , Karyotyping/veterinary , Lactoferrin/biosynthesis , Laminin , Pregnancy , Prolactin/pharmacology , Proteoglycans , Time Factors
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