Radiomics analysis of myocardial perfusion SPECT images in patients with cardiomyopathy and heart failure

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI Grants

Background

Although myocardial perfusion heterogeneity due to focally damaged cardiomyocytes is observed in single−photon emission computed tomography (SPECT) imaging, a current perfusion defect scoring system does not allow us to provide sufficient diagnostic information for heterogeneity.

Purpose

The aim of this study was to perform radiomics analysis of myocardial perfusion SPECT (MPS) images to investigate the potential to detect myocardial perfusion heterogeneity.

Methods

Patients with hypertrophic cardiomyopathy (n = 3), heart failure (n = 9), and with a low likelihood of coronary artery disease (n =15) (Figure 1), who underwent a rest 99mTc-MIBI myocardial perfusion SPECT, were assessed using a LIFEx software. Four shape−based features, 6 histogram−based features, and 32 textural features were computed. The relevant features for the classification of the patients were selected using the Boruta algorithm, and hierarchical clustering of the selected features using the Spearman correlation coefficient was also performed for the feature reduction. The receiver operating characteristics (ROC) analysis was performed by the support vector machine to calculate the area under the ROC curve (AUC) for the selected features.

Results

Of 40 features, 17 were selected by the classification analysis, and these features were classified into 7 classes by the correlation analysis (Figure 2). The ROC AUCs for 7 features extracted from each class were 0.99, 0.97, 0.96, 0.92, 0.90, 0.86, and 0.83 for the contrast of NDGLDM, the entropy of histogram, ZLNU of GLZLM, the energy of GLCM, the energy of histogram, SZLGE of GLZLM, and the correlation of GLCM, respectively, as compared to 0.39 for a summed rest score.

Conclusions

Radiomics analysis successfully determined the myocardial perfusion heterogeneity in patients with cardiomyopathy and heart failure. It might be promising for the evaluation of myocardial damages that cannot be analyzed by the conventional scoring method.

Effect of proinflammatory cytokines on endometrial collagen and metallopeptidase expression during the course of equine endometrosis

Equine endometrosis (endometrial fibrosis) is a degenerative chronic process that occurs in the uterus of the mare and disturbs proper endometrial function. Fibrosis is attributed to excessive deposition of extracellular matrix (ECM) components. The turnover of ECM is mediated by matrix metallopeptidases (MMP). Previously, it was shown that cytokines modulate MMP expression in other tissues and may regulate fibrosis indirectly by attracting inflammatory cells to the site of inflammation and directly on various tissues. However, the regulation of MMP expression in equine endometrosis is still relatively unknown. Thus, our aim was to determine if interleukin (IL)-1β and IL-6 regulate ECM, MMPs, or their inhibitors (TIMPs) and whether this regulation differs during endometrosis in the mare. Endometrial fibrosis was divided into four categories according to severity: I (no degenerative changes), IIA (mild degenerative changes), IIB (moderate degenerative changes) and III (severe degenerative changes) according to Kenney and Doig classification. Endometrial explants (n = 5 for category I, IIA, IIB and III according to Kenney and Doig) were incubated with IL-1β (10 ng/ml) or IL-6 (10 ng/ml) for 24 h. Secretion and mRNA transcription of collagen type 1 (Col1a1) and type 3 (Col3a1), fibronectin (Fn1), Mmp-1, -2, -3, -9, -13, Timp-1, -2 were analyzed by real-time PCR and ELISA, respectively. IL-1β treatment up-regulated secretion of COL1, MMP-2, TIMP1, and TIMP2 in category I endometrial fibrosis tissues (P < 0.05). IL-6 treatment up-regulated secretion of ECM, MMP-2, and MMP-3 and down-regulated secretion of MMP-9 in category I tissues (P < 0.05). In category IIA tissues, IL-1β and IL-6 treatment up-regulated secretion of COL3 (P < 0.05; P < 0.05), and IL-6 treatment also down-regulated secretion of MMP-9 (P < 0.05). In category IIB tissues, IL-1β treatment down-regulated secretion of COL3 (P < 0.05) and up-regulated secretion of MMP-3 (P < 0.01), while IL-6 treatment up-regulated secretion of MMP-3, MMP-9, and MMP-13 (P < 0.05). In category III tissues, IL-1β treatment up-regulated secretion of COL1, MMP-1, MMP-9 and TIMP-2 (P < 0.05), and IL-6 up-regulated secretion of all investigated ECM components, MMPs and TIMPs. These results reveal that the effect of IL-1β and IL-6 on equine endometrium differs depending on the severity of endometrial fibrosis. Our findings indicate an association between inflammation and development of endometrosis through the effect of IL-1β and IL-6 on expression of ECM components, MMPs, and TIMPs in the mare.

Postoperative changes in serum creatine kinase in paediatric orthopaedic patients with preoperative hyperCKaemia: review of three cases

An elevated serum creatine kinase (CK) level is commonly known as hyperCKaemia, and anaesthesiologists must take into account the potential susceptibility of hyperCKaemia patients to develop malignant hyperthermia during general anaesthesia as well as acute onset of rhabdomyolysis postoperatively. Three paediatric patients with hyperCKaemia were scheduled for orthopaedic surgery. With the consent of their parents, their CK changes were monitored for seven days postoperatively to detect rhabdomyolysis. The results showed that the postoperative CK change patterns were almost the same as those for patients whose CK levels were within reference range. Maximum CK levels tended to be higher in these patients than in the CK reference-range patients studied previously, although the reason remains unclear. This experience and previous studies suggest that measuring CK levels at least on postoperative days 1 and 2 might be better for detecting early signs of rhabdomyolysis, even in paediatric patients with hyperCKaemia.

Abstract P3-08-11: The prognostic impact of retinoic acid-induced 2 (RAI2) expression in ERα-positive breast cancer patients

Background: Breast cancer cells disseminate to the bone marrow and form bone metastases in a large majority of late-stage patients. Retinoic Acid-Induced 2 (RAI2) was reported as a putative suppressor of early hematogenous dissemination of tumor cells to the bone marrow in breast cancer, particularly in estrogen receptor α (ERα)-positive breast cancer. Here, we investigated mRNA expression of RAI-2 in breast cancer patients during long-term follow-up.

Materials and methods: A total of 451 invasive breast cancer tissues was available for analysis of RAI2 mRNA using a TaqMan PCR system. We also sought correlations between clinicopathological factors and levels of RAI2 expression in these samples. The expression of markers associated with tumor-initiating capacity, such as SNAI1, SNAI2 and VIM was also analyzed. The median follow-up period was 9.0 years. Survival curves were analyzed using the Kaplan-Meier method. Cox proportional hazards regression analysis was used for univariate and multivariate analyses of prognostic values.

Results: We found positive correlations between low expression of RAI2 mRNA and shorter disease-free survival and overall survival in breast cancer patients (P=0.003, P&lt;0.0001, respectively), which was limited to ERα-positive patients (P=0.04, P=0.0009, respectively), and not seen in ERα-negative patients (P=0.52, P=0.27, respectively). Low RAI2 mRNA levels were positively correlated with high grade, ERα-negativity and PgR negativity. Multivariate analysis indicated that low level RAI2 mRNA expression was an independent factor for survival both overall in breast cancer and in ERα-positive breast cancer patients

Multivariate analysis (ERα-positive breast cancer patients)  OS  Multivariate patientsp valueHR(95%CI)Tumor size≤2cm1390.83691 (Reference) &gt;2cm207 1.08(0.54-2.28)Node statusNegative176&lt;0.00011 (Reference) Positive144 4.72(2.33-10.34)Grade11240.95921 (Reference) 2•3218 0.98(0.50-2.14)RAI2 mRNA expressionhigh140&lt;0.00011 (Reference) middle•low206 4.79(2.14-12.78)

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Conclusion:We show that low expression of RAI2 is an independent factor predictive of a poor prognosis in ERα-positive breast cancer patients. RAI2 could be a promising candidate biomarker and therapeutic target in ERα-positive breast cancer to prevent dissemination to the bone marrow.

Citation Format: Nishikawa S, Kondo N, Endo Y, Hato Y, Hisada T, Nishimoto M, Dong Y, Okuda K, Kato H, Takahashi S, Nakanishi R, Toyama T. The prognostic impact of retinoic acid-induced 2 (RAI2) expression in ERα-positive breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-08-11.

Spatial Distribution and Temporal Trend of Anthropogenic Organic Compounds Derived from the 2011 East Japan Earthquake

The tsunami caused by the Great East Japan Earthquake on March 11, 2011 disturbed coastal environments in the eastern Tohoku region in Japan. Numerous terrestrial materials, including anthropogenic organic compounds, were deposited in the coastal zone. To evaluate the impacts of the disaster, we analyzed PCBs, LABs, PAHs, and hopanes in mussels collected from 12 locations in the east of Tohoku during 2011-2015 (series A) by GC-ECD or GC-MS and compared them with results from mussels collected from 22 locations around Japan during 2001-2004 (series B). Early LAB concentrations in series A at some locations were higher than the maximum concentrations in series B but decreased during the 5 years. Because LABs are molecular markers for sewage, these decreases are consistent with the recovery of sewage treatment plants in these areas. Early PAH concentrations at several locations were higher than the maximum concentrations in series B but also decreased. These high concentrations would have been derived from oil spills. The decreases of both LABs and PAHs indicate that these locations were affected by the tsunami but recovered. In contrast, later high concentrations of target compounds were detected sporadically at several locations. This pattern suggests that environmental pollution was caused by human activities, such as reconstruction. To understand the long-term trend of environmental pollution induced by the disaster, continuous monitoring along the Tohoku coast is required.

Perfusion MR Imaging Using a 3D Pulsed Continuous Arterial Spin-Labeling Method for Acute Cerebral Infarction Classified as Branch Atheromatous Disease Involving the Lenticulostriate Artery Territory

BACKGROUND AND PURPOSE

Branch atheromatous disease is a stroke subtype considered a risk factor for early neurologic deterioration. Meanwhile, crossed cerebellar diaschisis is thought to be influenced by the degree and location of supratentorial perfusion abnormalities and is associated with the clinical outcome in the case of an ischemic stroke. In this article, our aim was to clarify the utility of using a whole-brain 3D pulsed continuous arterial spin-labeling method as an imaging biomarker for predicting neurologic severity in branch atheromatous disease.

MATERIALS AND METHODS

Twenty-three patients with branch atheromatous disease in the lenticulostriate artery territory were enrolled. All patients underwent MR imaging, including DWI, 3D-TOF-MRA, and 3D-arterial spin-labeling. We measured the asymmetry index of CBF in the affected area (branch atheromatous disease), the asymmetry index of the contralateral cerebellar hemisphere (crossed cerebellar diaschisis), and the DWI infarct volume in the lenticulostriate artery territory. We also compared each parameter with the initial NIHSS score with the Pearson correlation coefficient.

RESULTS

Among the 23 patients, we found no correlation between NIHSS score and the asymmetry index of CBF in the affected area (branch atheromatous disease) (r = -0.027, P = .724), whereas the asymmetry index of the contralateral cerebellar hemisphere (crossed cerebellar diaschisis) and DWI infarct volumes were significantly correlated with NIHSS score (r = 0.515, P = .012; r = 0.664, P = .001, respectively).

CONCLUSIONS

In patients with branch atheromatous disease, 3D-arterial spin-labeling can detect crossed cerebellar diaschisis, which is correlated with the degree of neurologic severity.

Constitutively active ABL family kinases, TEL/ABL and TEL/ARG, harbor distinct leukemogenic activities in vivo

ABL (ABL1) and ARG (ABL2) are highly homologous to each other in overall domain structure and amino-acid sequence, with the exception of their C termini. As with ABL, translocations that fuse ARG to ETV6/TEL have been identified in patients with leukemia. To assess the in vivo leukemogenic activity of constitutively active ABL and ARG, we generated a bone marrow (BM) transplantation model using the chimeric forms TEL/ABL and TEL/ARG, which have comparable kinase activities. TEL/ABL rapidly induced fatal myeloid leukemia in recipient mice, whereas recipients of TEL/ARG-transduced cells did not develop myeloid leukemia, instead, they succumbed to a long-latency infiltrative mastocytosis that could be adoptively transferred to secondary recipients. Swapping of the C termini of ABL and ARG altered disease latency and phenotypes. In a detailed in vitro study, TEL/ARG strongly promoted mast cell differentiation in response to stem cell factor or interleukin-3, whereas TEL/ABL preferentially induced myeloid differentiation of hematopoietic stem/progenitor cells. These results indicate that ABL and ARG kinase activate distinct differentiation pathways to induce specific diseases in vivo, that is, myeloid leukemia and mastocytosis, respectively. Further elucidation of the differences in their properties should provide important insight into the pathogenic mechanisms of oncogenes of the ABL kinase family.

Chemical Endoplasmic Reticulum Chaperone Alleviates Doxorubicin-Induced Cardiac Dysfunction

RATIONALE

Doxorubicin is an effective chemotherapeutic agent for cancer, but its use is often limited by cardiotoxicity. Doxorubicin causes endoplasmic reticulum (ER) dilation in cardiomyocytes, and we have demonstrated that ER stress plays important roles in the pathophysiology of heart failure.

OBJECTIVE

We evaluated the role of ER stress in doxorubicin-induced cardiotoxicity and examined whether the chemical ER chaperone could prevent doxorubicin-induced cardiac dysfunction.

METHODS AND RESULTS

We confirmed that doxorubicin caused ER dilation in mouse hearts, indicating that doxorubicin may affect ER function. Doxorubicin activated an ER transmembrane stress sensor, activating transcription factor 6, in cultured cardiomyocytes and mouse hearts. However, doxorubicin suppressed the expression of genes downstream of activating transcription factor 6, including X-box binding protein 1. The decreased levels of X-box binding protein 1 resulted in a failure to induce the expression of the ER chaperone glucose-regulated protein 78 which plays a major role in adaptive responses to ER stress. In addition, doxorubicin activated caspase-12, an ER membrane-resident apoptotic molecule, which can lead to cardiomyocyte apoptosis and cardiac dysfunction. Cardiac-specific overexpression of glucose-regulated protein 78 by adeno-associated virus 9 or the administration of the chemical ER chaperone 4-phenylbutyrate attenuated caspase-12 cleavage, and alleviated cardiac apoptosis and dysfunction induced by doxorubicin.

CONCLUSIONS

Doxorubicin activated the ER stress-initiated apoptotic response without inducing the ER chaperone glucose-regulated protein 78, further augmenting ER stress in mouse hearts. Cardiac-specific overexpression of glucose-regulated protein 78 or the administration of the chemical ER chaperone alleviated the cardiac dysfunction induced by doxorubicin and may facilitate the safe use of doxorubicin for cancer treatment.

Heat devices in nonlinear irreversible thermodynamics

We present results obtained by using nonlinear irreversible models for heat devices. In particular, we focus on the global performance characteristics, the maximum efficiency and the efficiency at maximum power regimes for heat engines, and the maximum coefficient of performance (COP) and the COP at maximum cooling power regimes for refrigerators. We analyze the key role played by the interplay between irreversibilities coming from heat leaks and internal dissipations. We also discuss the relationship between these results and those obtained by different models.

104 EXPRESSION OF ACTIVIN A AS A LOCAL REGULATOR IN THE BOVINE OVIDUCT

Activin (ACV) is known as a local regulator of several reproductive functions including follicular development and implantation in mammals. ACVA is a glycopeptide belonging to the transforming growth factor β superfamily, and is a homodimer of inhibin ßA (INHBA) subunits. Follistatin (FST), an ACV-specific binding protein, inhibits ligand-receptor binding. ACV receptor (ACVR) is a hetero-tetramer consisting of 2 kinds of protein, ACVR1 or ACVR1B and ACVR2A or ACVR2B. The oviduct provides an optimal environment for sperm capacitation, fertilization, and early embryonic development. Previous reports have demonstrated that ACVRs were expressed in bovine oocytes and embryos, and that early embryonic development is facilitated by ACVA in vitro. ACVA produced by the bovine oviduct may affect gametes and embryos as well as oviductal cells as a local regulator in cow. Bovine oviductal samples were classified into 6 stages of the oestrous cycle (day of ovulation; Days 2–3 after ovulation; Days 5–6; Days 8–12; Days 15–17; Days 19–21). We examined (1) protein expression of ACVA and FST in oviductal fluid collected from the ampulla and isthmus, (2) mRNA expression of INHBA and FST in the ampullary and isthmic oviductal tissues during the oestrous cycle, (3) the effects of oestradiol-17β (E2: 0.1, 1, 10 nM) and progesterone (P4: 1, 10, 100 nM) on mRNA expressions of INHBA and FST in cultured oviductal epithelial cells isolated from the ampulla and isthmus, and (4) mRNA expression of ACVRs in tissues and in cultured epithelial and stromal cells. The main findings were as follows: (1) Both ACVA and FST were detected throughout the oestrous cycle in the oviductal fluid of the ampulla and isthmus. (2) INHBA expression was higher in the isthmus than in the ampulla. FST expression in the ampulla was lowest at peri-ovulation, INHBA expression in the isthmus was highest on the day of ovulation and FST in the isthmus during Days 2–6 was highest. Because an increase of ACVA production and a decrease of FST production raise ACVA bioactivity, ACVA seems to be most active at peri-ovulation in both the ampulla and isthmus. (3) In the cultured isthmic oviductal epithelial cells, 10 nM E2 significantly stimulated INHBA expression, but tended to suppress FST expression. Therefore, the bioactivity of ACVA seems to be controlled by E2 during the oestrous cycle in the isthmus. (4) The expression of ACVR1B and ACVR2A was clearly detected in the tissues as well as in cultured epithelial and stromal cells. The overall findings suggest that ACVA secreted into oviductal fluid plays an important role in oviductal functions, including fertilization in the ampulla and sperm motility and viability in the isthmus. It is also suggested that ACVA acts on both epithelial and stromal cells as a local regulator of cellular functions, such as cellular proliferation and secretion in the cow.

105 EFFECT OF LYSOPHOSPHATIDIC ACID ON PROSTAGLANDIN PRODUCTION IN THE BOVINE OVIDUCT

The oviduct is an essential organ for successful pregnancy in mammals. The transport of gametes and early embryos is mainly induced by contraction and relaxation of smooth muscle. The contraction and relaxation of bovine oviductal smooth muscle are induced by prostaglandin (PG) F2α and PGE2, respectively. Lysophosphatidic acid (LPA), a type of phospholipid, is involved in various physiological actions such as promoting inflammation and cellular proliferation in various organs. LPA acts through at least 6 G protein-coupled receptors. Both LPA and LPA receptors are expressed in endometrium and, moreover, LPA affects PG production by the endometrium in cow. Based on the above findings, we hypothesised that LPA is locally involved in PG production by oviductal cells to promote motility of oviductal smooth muscle in cow. Oviductal samples ipsilateral to a corpus luteum or a dominant follicle at peri-ovulation (0–6 and 19–21 days after ovulation) were collected in abattoir. Messenger RNA expression of LPA receptors (LPAR1–6) and LPA-producing enzymes (ATX, PLA1α, PLA1β) was examined in ampullary and isthmic tissues. Expression in cultured epithelial and stromal cells isolated from the bovine oviduct were also examined to determine the cells possessing LPA receptors and LPA-producing enzymes. In addition, the effect of LPA (0.1, 1, 10 μM) on the expression of cyclooxygenase (COX)-1 and COX-2 (PG-synthesising enzymes) and on PGE2 and PGF2α production by cultured epithelial and stromal cells was investigated. The significant differences (P < 0.05) were determined by Student's t-test for 2 groups, and by one-way ANOVA followed by Tukey's multiple comparison test for more than 3 groups. LPAR1–6, ATX, PLA1α, and PLA1β were expressed in both ampullary and isthmic tissues as well as in both cultured epithelial and stromal cells. The expression of LPAR1–3 was significantly lower in the isthmic tissues than in the ampullary tissues, whereas the expression of LPAR4–6 was significantly higher in the isthmic tissues than in the ampullary tissues. The expression of COX-2 was significantly stimulated by 10 μM LPA in cultured isthmic stromal cells. In addition, LPA significantly stimulated both PGE2 and PGF2α production by cultured isthmic stromal cells. In the isthmus of the oviduct, LPA produced by epithelial and stromal cells may stimulate the expression of COX-2 in the stromal cells, followed by increased PG production. Because the mRNA expression of LPAR4–6 is higher in the isthmus than in the ampulla, those effects of LPA might be mediated by activation of LPAR4–6. The overall findings suggest that LPA is one of the regulating factors for transport of gametes and early embryos by controlling the motility of smooth muscle in the bovine oviduct.

Structural Study of Amorphous Co-Ferrite Film by Anomalous X-Ray Scattering

The structure of amorphous Co-ferrite film grown on a glass substrate was studied by anomalous X-ray scattering (AXS). Co atoms cannot be distinguished from Fe atoms with the usual X-ray diffraction technique. Therefore the AXS method at the Fe and Co K-absorption edges was adopted. In the previous AXS studies only the lower energy side of the absorption edges was adopted. In the previous AXS studies only the lower energy side of the absorption edge was used. In the present case, the lower energy side of the Co K-absorption edge corresponds to the higher energy side of the Fe K-absorption edge. Therefore, in order to overcome this inconvenience, the scattering was measured on both sides of the absorption edge, thus enabling the independent determination of the oxygen coordination numbers around Co and Fe in the ferrite film from the environmental RDFs estimated from the energy differential profiles by coupling with the linear least squares technique.

Three-dimensional surface figure measurement of high-accuracy spherical mirror with nanoprofiler using normal vector tracing method

Processing technology using an extreme ultraviolet light source, e.g., next-generation lithography, requires next-generation high-accuracy mirrors. As it will be difficult to attain the degree of precision required by next-generation high-accuracy mirrors such as aspherical mirrors through conventional processing methods, rapid progress in nanomeasurement technologies will be needed to produce such mirrors. Because the measuring methods used for the surface figure measurement of next-generation mirrors will require high precision, we have developed a novel nanoprofiler that can measure the figures of high-accuracy mirrors without the use of a reference surface. Because the accuracy of the proposed method is not limited by the accuracy of a reference surface, the measurement of free-form mirrors is expected to be realized. By using an algorithm to process normal vectors and their coordinate values at the measurement point obtained by a nanoprofiler, our measurement method can reconstruct three-dimensional shapes. First, we measured the surface of a concave spherical mirror with a 1000-mm radius of curvature using the proposed method, and the measurement repeatability is evaluated as 0.6 nm. Sub-nanometer repeatability is realized, and an increase in the repeatability would be expected by improving the dynamic stiffness of the nanoprofiler. The uncertainty of the measurement using the present apparatus is estimated to be approximately 10 nm by numerical simulation. Further, the uncertainty of a Fizeau interferometer is also approximately 10 nm. The results obtained using the proposed method are compared with those obtained using a Fizeau interferometer. The resulting profiles are consistent within the range of each uncertainty over the middle portions of the mirror.

Influence of prostaglandin F₂α analogues on the secretory function of bovine luteal cells and ovarian arterial contractility in vitro

Although prostaglandin (PG) F2α analogues are routinely used for oestrus synchronisation in cattle, their effects on the function of the bovine corpus luteum (CL), and on ovarian arterial contractility, may not reflect the physiological effects of endogenous PGF2α. In the first of two related experiments, the effects of different analogues of PGF2α (aPGF2α) on the secretory function and apoptosis of cultured bovine cells of the CL were assessed. Enzymatically-isolated bovine luteal cells (from between days 8 and 12 of the oestrous cycle), were stimulated for 24h with naturally-occurring PGF2α or aPGF2α (dinoprost, cloprostenol or luprostiol). Secretion of progesterone (P4) was determined and cellular [Ca(2+)]i mobilisation, as well as cell viability and apoptosis were measured. Naturally-occurring PGF2α and dinoprost stimulated P4 secretion (P<0.05), whereas cloprostenol and luprostiol did not influence P4 synthesis. The greatest cytotoxic and pro-apoptotic effects were observed in the luprostiol-treated cells, at 37.3% and 202%, respectively (P<0.001). The greatest effect on [Ca(2+)]i mobilisation in luteal cells was observed post-luprostiol treatment (200%; P<0.001). In a second experiment, the influence of naturally-occurring PGF2α and aPGF2α on ovarian arterial contraction in vitro, were examined. No differences in the effects of dinoprost or naturally-occurring PGF2α were found across the studied parameters. The effects of cloprostenol and luprostiol on luteal cell death, in addition to their effects on ovarian arterial contractility, were much greater than those produced by treatment with naturally-occurring PGF2α.

Lipopolysaccharides, cytokines, and nitric oxide affect secretion of prostaglandins and leukotrienes by bovine mammary gland epithelial cells

The aims of this study were to determine the effects of lipopolysaccharides (LPS), tumor necrosis factor (TNF), interleukin 1 alpha (IL-1α), nitric oxide donor (NONOate), or the combination of TNF + IL-1α + NONOate on the following: (i) secretion of prostaglandin (PG)-F(2α), PGE(2), leukotriene (LT)-B(4), and LTC(4) by epithelial cells of the teat cavity and lactiferous sinus of bovine mammary gland; (ii) messenger RNA (mRNA) transcription of enzymes responsible for arachidonic acid (AA) metabolism (prostaglandin-endoperoxide synthase 2 [PTGS2], prostaglandin E synthase [PTGES], prostaglandin F synthase [PGFS], and arachidonate 5-lipooxygenase [ALOX5]); and (iii) proliferation of the cells. The cells were stimulated for 24 h. Prostaglandins and LT were measured by enzyme immunoassay, mRNA transcription of enzymes was determined by real-time reverse transcription polymerase chain reaction, and the cell viability was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide. All factors increased PG secretion, but the highest stimulation was observed after TNF and IL-1α (P < 0.001). Tumor necrosis factor, NONOate, and TNF + IL-1α + NONOate increased LTB(4) production (P < 0.01), whereas LTC(4) was increased by LPS, TNF, and IL-1α (P < 0.01). Lipopolysaccharides, TNF, IL-1α, and the reagents combination increased PTGS2, PTGES, and PGFS mRNA transcription (P < 0.01), whereas ALOX5 mRNA transcription was increased only by TNF (P < 0.001). Lipopolysaccharides, TNF, IL-1α, NONOate, and the combination of reagents increased the cell number (P < 0.001). Mediators of acute-clinical Escherichia coli mastitis locally modulate PG and LT secretion by the epithelial cells of the teat cavity and lactiferous sinus, which might be a useful first line of defense for the bovine mammary gland. Moreover, the modulation of PG and LT secretion and the changing ratio of luteotropic (PGE(2), LTB(4)) to luteolytic (PGF(2α), LTC(4)) metabolites may contribute to disorders in reproductive functions.