Neuropeptide Y directly affects ovarian cell proliferation and apoptosis

We have demonstrated that neuropeptide Y (NPY), abundantly produced by enteric neurons, is an important regulator of intestinal inflammation. However, the role of NPY in the progression of chronic inflammation to tumorigenesis is unknown. We investigated whether NPY could modulate epithelial cell proliferation and apoptosis, and thus regulate tumorigenesis. Repeated cycles of dextran sodium sulfate (DSS) were used to model inflammation-induced tumorigenesis in wild-type (WT) and NPY knockout ( NPY−/−) mice. Intestinal epithelial cell lines (T84) were used to assess the effects of NPY (0.1 µM) on epithelial proliferation and apoptosis in vitro. DSS-WT mice exhibited enhanced intestinal inflammation, polyp size, and polyp number (7.5 ± 0.8) compared with DSS- NPY−/− mice (4 ± 0.5, P < 0.01). Accordingly, DSS-WT mice also showed increased colonic epithelial proliferation (PCNA, Ki67) and reduced apoptosis (TUNEL) compared with DSS- NPY−/− mice. The apoptosis regulating microRNA, miR-375, was significantly downregulated in the colon of DSS-WT (2-fold, P < 0.01) compared with DSS- NPY−/−-mice. In vitro studies indicated that NPY promotes cell proliferation (increase in PCNA and β-catenin, P < 0.05) via phosphatidyl-inositol-3-kinase (PI3-K)-β-catenin signaling, suppressed miR-375 expression, and reduced apoptosis (increase in phospho-Bad). NPY-treated cells also displayed increased c-Myc and cyclin D1, and reduction in p21 ( P < 0.05). Addition of miR-375 inhibitor to cells already treated with NPY did not further enhance the effects induced by NPY alone. Our findings demonstrate a novel regulation of inflammation-induced tumorigenesis by NPY-epithelial cross talk as mediated by activation of PI3-K signaling and downregulation of miR-375. NEW & NOTEWORTHY Our work exemplifies a novel role of neuropeptide Y (NPY) in regulating inflammation-induced tumorigenesis via two modalities: first by enhanced proliferation (PI3-K/pAkt), and second by downregulation of microRNA-375 (miR-375)-dependent apoptosis in intestinal epithelial cells. Our data establish the existence of a microRNA-mediated cross talk between enteric neurons producing NPY and intestinal epithelial cells, and the potential of neuropeptide-regulated miRNAs as potential therapeutic molecules for the management of inflammation-associated tumors in the gut.

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cAMP response element-binding protein 1 controls porcine ovarian cell proliferation, apoptosis, and FSH and insulin-like growth factor 1 response

Reproduction Fertility and Development ◽

10.1071/rd17508 ◽

2018 ◽

Vol 30 (8) ◽

pp. 1145 ◽

Cited By ~ 5

Author(s):

A. V. Sirotkin ◽

A. Benčo ◽

A. Tandlmajerová ◽

M. Lauková ◽

D. Vašíček ◽

...

Keyword(s):

Cell Proliferation ◽

Growth Factor ◽

Camp Response Element Binding ◽

Insulin Like Growth Factor ◽

Camp Response Element ◽

Response Element ◽

Ovarian Cell ◽

Proliferation And Apoptosis ◽

Element Binding Protein ◽

Series Of Experiments

The aim of the present study was to examine the role of cAMP response element-binding protein (CREB) and its phosphorylation in the regulation of ovarian cell proliferation and apoptosis, and of the response of proliferation and apoptosis to the upstream hormonal stimulators FSH and insulin-like growth factor (IGF) 1. In the first series of experiments, porcine ovarian granulosa cells, transfected or not with a gene construct encoding wild-type CREB1 (CREB1WT), were cultured with and without FSH (0, 1, 10 or 100 ng mL−1). In the second series of experiments, these cells were transfected or not with CREB1WT or non-phosphorylatable mutant CREB1 (CREB1M1) and cultured with and without FSH (0, 1, 10 or 100 ng mL−1) or IGF1 (0, 1, 10 and 100 ng mL−1). Levels of total and phosphorylated (p-) CREB1, proliferating cell nuclear antigen (PCNA), a marker of proliferation, and BAX, a marker of apoptosis, were evaluated by western immunoblotting and immunocytochemical analysis. Transfection of cells with CREB1WT promoted accumulation of total CREB1 within cells, but p-CREB1 was not detected in any cell group. Both CREB1WT and CREB1M1 reduced cell proliferation and apoptosis. Addition of 10 and 100 ng mL−1 FSH to non-transfected cells promoted CREB1 accumulation and apoptosis, whereas cell proliferation was promoted by all concentrations of FSH tested. FSH activity was not modified in cells transfected with either CREB1WT or CREB1M1. IGF1 at 100 ng mL−1 promoted cell proliferation, whereas all concentrations of IGF1 tested reduced apoptosis. Transfection with either CREB1WT or CREB1M1 did not modify the effects of either FSH or IGF1, although CREB1M1 reversed the effect of IGF1 on apoptosis from inhibitory to stimulatory. These observations suggest that CREB1 is involved in the downregulation of porcine ovarian cell proliferation and apoptosis. The absence of visible CREB1 phosphorylation and the similarity between the effects of CREB1WT and CREB1M1 transfection indicate that phosphorylation is not necessary for CREB1 action on these processes. Furthermore, the observations suggest that FSH promotes both ovarian cell proliferation and apoptosis, whereas IGF1 has proliferation-promoting and antiapoptotic properties. The effect of FSH on CREB1 accumulation and the ability of CREB1M1 to reverse the effects of IGF1 on apoptosis indicate that CREB1 is a mediator of hormonal activity, but the inability of either CREB1WT or CREBM1transfection to modify the primary effects of FSH and IGF1 suggest that CREB1 and its phosphorylation do not mediate the action of these hormones on ovarian cell proliferation and apoptosis.

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Resistin is a survival factor for porcine ovarian follicular cells

Reproduction ◽

10.1530/rep-15-0255 ◽

2015 ◽

Vol 150 (4) ◽

pp. 343-355 ◽

Cited By ~ 17

Author(s):

Agnieszka Rak ◽

Eliza Drwal ◽

Anna Wróbel ◽

Ewa Łucja Gregoraszczuk

Keyword(s):

Cell Proliferation ◽

Protein Expression ◽

Western Blot ◽

Dna Fragmentation ◽

Cell Apoptosis ◽

Caspase 3 ◽

Inhibitory Effect ◽

Ovarian Cell ◽

Proliferation And Apoptosis ◽

Mrna And Protein Expression

Previously, we demonstrated the expression of resistin in the porcine ovary, the regulation of its expression and its direct effect on ovarian steroidogenesis. The objective of this study was to examine the effect of resistin on cell proliferation and apoptosis in a co-culture model of porcine granulosa and theca cells. First, we analysed the effect of resistin at 1 and 10 ng/ml alone or in combination with FSH- and IGF1 on ovarian cell proliferation with an alamarBlue assay and protein expression of cyclins A and B using western blot. Next, the mRNA and protein expression of selected pro-apoptotic and pro-survival regulators of cell apoptosis, caspase-9, -8 and -3 activity and DNA fragmentation using real time PCR, western blot, fluorescent assay and an ELISA kit, respectively, were analysed after resistin treatment. Furthermore, we determined the effect of resistin on the protein expression of ERK1/2, Stat and Akt kinase. Using specific inhibitors of these kinases, we also checked caspase-3 activity and protein expression. We found that resistin, at both doses, has no effect on cell proliferation. The results showed that resistin decreased pro-apoptotic genes, which was confirmed on protein expression of selected factors. We demonstrate an inhibitory effect of resistin on caspase activity and DNA fragmentation. Finally, resistin stimulated phosphorylation of the ERK1/2, Stat and Akt and kinases inhibitors reversed resistin action on caspase-3 activity and protein expression to control. All of these results showed that resistin has an inhibitory effect on porcine ovarian cell apoptosis by activation of the MAPK/ERK, JAK/Stat and Akt/PI3 kinase signalling pathways.

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Fennel affects ovarian cell proliferation, apoptosis, and response to ghrelin

Physiological Research ◽

10.33549/physiolres.934546 ◽

2021 ◽

pp. 237-243

Author(s):

AV Sirotkin ◽

R Alexa ◽

S Alwasel ◽

AH Harrath

Keyword(s):

Cell Proliferation ◽

Cell Apoptosis ◽

Proliferation Marker ◽

Direct Effects ◽

Ovarian Cell ◽

Animal Reproduction ◽

Ovarian Cells ◽

Proliferation And Apoptosis ◽

Series Of Experiments ◽

Apoptosis Marker

The objective of this study was to examine the direct effects of the medicinal plant fennel (Foeniculum vulgare Mill.) on basic functions of ovarian cells, including proliferation, apoptosis, and response to the physiological hormonal stimulator, ghrelin. In the first series of experiments, porcine ovarian granulosa cells were cultured with (1, 10, 100 µg/ml) or without fennel extract. In the second series of experiments, cells were cultured with (1, 10, 100 ng/ml) or without ghrelin, alone or in combination with fennel extract (10 µg/ml). Expression of the proliferation marker, PCNA, and the apoptosis marker, bax, were analyzed via quantitative immunocytochemical methods. Fennel stimulated the accumulation of the proliferation marker, and suppressed the expression of the apoptosis marker. Ghrelin alone promoted proliferation and apoptosis of ovarian cells. The presence of fennel inhibited these ghrelin effects. These observations provide the first demonstration of (1) effects of fennel on farm animal reproduction, (2) direct effects of fennel on ovarian cells, (3) the ability of fennel to promote ovarian cell proliferation, to inhibit ovarian cell apoptosis, and to enhance the ovarian cell proliferation:apoptosis ratio. Furthermore, our results (4) confirm the involvement of ghrelin in the control of ovarian cell apoptosis and proliferation, and (5) demonstrate the ability of fennel to affect not only ovarian cell proliferation and apoptosis, but also to suppress the responses of ovarian cells to the upstream hormonal regulator ghrelin. Our results indicate the potential applicability of fennel as a bio-stimulator of farm animal reproduction.

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Effects of PKC beta inhibitor enzastaurin on parental and chemoresistant ovarian cancer cell lines

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.20037 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 20037-20037 ◽

Cited By ~ 4

Author(s):

I. Meinhold-Heerlein ◽

D. O. Bauerschlag ◽

K. Bräutigam ◽

N. Maass ◽

C. Mundhenke ◽

...

Keyword(s):

Ovarian Cancer ◽

Cell Proliferation ◽

Cell Line ◽

Cell Lines ◽

Cancer Cell ◽

Ovarian Cancer Cell ◽

High Expression ◽

Expression Level ◽

Ovarian Cell ◽

Proliferation And Apoptosis

20037 Background: Enzastaurin (LY317615.HCl), a selective inhibitor of protein kinase C beta (PKCβ), inhibits induction of angiogenesis and apoptosis. Activation of PKCβ has been correlated with tumor cell proliferation and invasiveness. The impact of Enzastaurin was investigated in an ovarian cancer tissue culture model utilizing the parental cell line HEY and resistant subclones against different cytostatic drugs. Methods: The ovarian cancer cell line HEY was used to develop subclones with selective resistance against Cisplatin, Etoposide, Docetaxel and Paclitaxel, respectively. The ovarian cell line IGROV-1 with high expression of PKC beta served as control. All cell lines were stimulated with 5 μM Enzastaurin for up to four hours. Immunoblotting analyses determined the expression of GSK3β, a target of PKCβ. Proliferation and apoptosis induction after Enzastaurin treatment was analysed by a proliferation assay and DAPI staining. Results: All cell lines showed phosphorylation of GSK3β, the highest expression level was found in parental and Cisplatin-resistant HEY cells as well as in IGROV-1 cells. Phosphorylation decreased after stimulation with 5 μM Enzastaurin for 30 minutes, most obvious detectable in parental and Cisplatin-resistent HEY cells and also IGROV-1 cells. Proliferation and apoptosis assays demonstrated the Paclitaxel- and Docetaxel-resistant HEY cells as the most sensitive cell lines for Enzastaurin treatment. In contrast, Cisplatin-resistant HEY cells and IGROV-1 cells exhibited the highest resistance against Enzastaurin. Conclusion: The results indicate that ovarian cell lines with a high expression level of active PKCβ like Cisplatin-resistant HEY cells and IGROV-1 cells display also strong phosphorylation of GSK3β. Though in these cell lines the inhibitory effect of Enzastaurin is most prominent, the cell proliferation is hardly affected, nor apoptosis is accelerated when Enzastaurin concentrations up to 10–15 μM were used. Compared to the Cisplatin-resistant variants the normal HEY cells are more sensitive to the inhibitor. Taxane-resistant cells seem to respond to low concentrations of Enzastaurin. Therefore, Enzastaurin may become an effectful drug to treat ovarian carcinomas with resistance to Taxane-based chemotherapies. [Table: see text]

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