Activation of Enteroendocrine Membrane Progesterone Receptors Promotes Incretin Secretion and Improves Glucose Tolerance in Mice

Background: To investigate the potential synergistic effects of olive oil releasing 2-oleoylglycerol and hydrolyzed pine nut oil containing 20% pinolenic acid on GLP-1 secretion, glucose tolerance, insulin secretion and appetite in healthy individuals, when delivered to the small intestine as potential agonists of GPR119, FFA1 and FFA4. Methods: Nine overweight/obese individuals completed three 6-h oral glucose tolerance tests (OGTTs) in a crossover design. At -30 min, participants consumed either: no oil, 6 g of hydrolyzed pine nut oil (PNO-FFA), or a combination of 3 g hydrolyzed pine nut oil and 3 g olive oil (PNO-OO) in delayed-release capsules. Repeated measures of glucose, insulin, C-peptide, GLP-1, GIP, ghrelin, subjective appetite and gastrointestinal tolerability were done. Results: PNO-FFA augmented GLP-1 secretion from 0–360 min compared to no oil and PNO-OO (p < 0.01). GIP secretion was increased from 240–360 min after both PNO-FFA and PNO-OO versus no oil (p < 0.01). Both oil treatments suppressed subjective appetite by reducing hunger and prospective food consumption and increasing satiety (p < 0.05). Conclusions: In support of previous findings, 6 g of delayed-release hydrolyzed pine nut oil enhanced postprandial GLP-1 secretion and reduced appetite. However, no synergistic effect of combining hydrolyzed pine nut oil and olive oil on GLP-1 secretion was observed. These results need further evaluation in long-term studies including effects on bodyweight and insulin sensitivity.

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Nuclear and membrane progesterone receptors expression in placenta from early to late pregnancy in sheep: Effects of restricted nutrition and realimentation

Theriogenology ◽

10.1016/j.theriogenology.2020.02.041 ◽

2020 ◽

Vol 148 ◽

pp. 95-102

Author(s):

Thanya Bunma ◽

Kimberly A. Vonnahme ◽

Manuel A. Vasquez-Hidalgo ◽

Kendall C. Swanson ◽

Sheri T. Dorsam ◽

...

Keyword(s):

Progesterone Receptors ◽

Late Pregnancy ◽

Membrane Progesterone Receptors

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Heterologous expression of human mPRα, mPRβ and mPRγ in yeast confirms their ability to function as membrane progesterone receptors

Steroids ◽

10.1016/j.steroids.2008.05.003 ◽

2008 ◽

Vol 73 (11) ◽

pp. 1160-1173 ◽

Cited By ~ 72

Author(s):

Jessica L. Smith ◽

Brian R. Kupchak ◽

Ibon Garitaonandia ◽

L. Kim Hoang ◽

Andrew S. Maina ◽

...

Keyword(s):

Heterologous Expression ◽

Progesterone Receptors ◽

Membrane Progesterone Receptors

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Expression of membrane progesterone receptors (mPRs) in rat peripheral glial cell membranes and their potential role in the modulation of cell migration and protein expression

Steroids ◽

10.1016/j.steroids.2017.09.009 ◽

2019 ◽

Vol 142 ◽

pp. 6-13 ◽

Cited By ~ 10

Author(s):

Luca F. Castelnovo ◽

Valerio Magnaghi ◽

Peter Thomas

Keyword(s):

Cell Migration ◽

Protein Expression ◽

Glial Cell ◽

Cell Membranes ◽

Potential Role ◽

Progesterone Receptors ◽

Membrane Progesterone Receptors

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Distribution and hormonal regulation of membrane progesterone receptors β and γ in ciliated epithelial cells of mouse and human fallopian tubes

Reproductive Biology and Endocrinology ◽

10.1186/1477-7827-7-89 ◽

2009 ◽

Vol 7 (1) ◽

pp. 89 ◽

Cited By ~ 40

Author(s):

Magdalena Nutu ◽

Birgitta Weijdegård ◽

Peter Thomas ◽

Ann Thurin-Kjellberg ◽

Håkan Billig ◽

...

Keyword(s):

Epithelial Cells ◽

Hormonal Regulation ◽

Progesterone Receptors ◽

Fallopian Tubes ◽

Membrane Progesterone Receptors ◽

Ciliated Epithelial Cells

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Progesterone signals through membrane progesterone receptors (mPRs) in MDA-MB-468 and mPR-transfected MDA-MB-231 breast cancer cells which lack full-length and N-terminally truncated isoforms of the nuclear progesterone receptor

Steroids ◽

10.1016/j.steroids.2011.01.008 ◽

2011 ◽

Cited By ~ 3

Author(s):

Yefei Pang ◽

Peter Thomas

Keyword(s):

Breast Cancer ◽

Progesterone Receptor ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Progesterone Receptors ◽

Full Length ◽

Membrane Progesterone Receptors ◽

Truncated Isoforms ◽

Nuclear Progesterone Receptor

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Interactions between progesterone and tumor necrosis factor-α in the regulation of primordial follicle assembly

Reproduction ◽

10.1530/rep-06-0045 ◽

2006 ◽

Vol 132 (6) ◽

pp. 877-886 ◽

Cited By ~ 36

Author(s):

Eric E Nilsson ◽

Jacob Stanfield ◽

Michael K Skinner

Keyword(s):

Tumor Necrosis Factor ◽

Cell Survival ◽

Tumor Necrosis ◽

Tumor Necrosis Factor Α ◽

Surface Membrane ◽

Progesterone Receptors ◽

Primordial Follicle ◽

Membrane Progesterone Receptors ◽

Factor Α ◽

Necrosis Factor

Follicle assembly is the process by which groups or ‘nests’ of oocytes break down to form primordial follicles. The size of the primordial follicle pool is the major determinant of the reproductive lifespan of a female. Previously, progesterone (P4) has been shown to inhibit follicle assembly, while tumor necrosis factor-α (TNFα) has been shown to promote the apoptosis that is necessary for follicle assembly. The present study examines how TNFα and progesterone interact to regulate primordial follicle assembly. Ovaries were collected from newborn rats and placed in organ culture to examine the actions of P4 and TNFα. P4 was found to decrease primordial follicle assembly and increase the percentage of unassembled oocytes both in vitro and in vivo. TNFα treatment did not change the proportion of assembled follicles in cultured ovaries, but blocked the ability of P4 to inhibit follicle assembly. Microarray analysis of the ovarian transcriptome revealed that progesterone treatment of the ovaries altered the expression of 513 genes with 132 only expressed after P4 treatment and 16 only expressed in control ovaries. The majority of genes were up-regulated greater than twofold over control, with a small subset of 16 genes down-regulated. Categories of genes affected by P4 are described including a group of extracellular signaling factors. The progesterone receptors expressed at the time of follicle assembly included the surface membrane progesterone receptors PGRMC1, PGRMC2, and RDA288. The nuclear genomic P4 receptor was not expressed at appreciable levels. Progesterone increased the expression of several genes (TANK, NFκB, Bcl2l1, and Bcl2l2) involved in a signaling pathway that promotes cell survival and inhibits apoptosis. Observations indicate that P4 acts through the surface membrane progesterone receptors to regulate primordial follicle assembly, and that TNFα can override the inhibitory actions of P4 on follicle assembly. A major mechanism involved in the actions of P4 is an increase in cell survival genes and inhibition of the apoptosis pathway. Observations provide insight into the hormonal regulation of primordial follicle assembly and lead to novel approaches to potentially manipulate follicle assembly and reproductive capacity.

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