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Effects of Bisphenol-A on proliferation and expression of genes related to synthesis of polyamines, interferon tau and insulin-like growth factor 2 by ovine trophectoderm cells

Elmetwally, Mohammed A.; Halawa, Amal A.; Lenis, Yasser Y.; Tang, Wanjin; Wu, Guoyao; Bazer, Fuller W. (2018)

This study evaluated the effects of bisphenol A (BPA) on proliferation of ovine trophectoderm (oTr1) cells, as well as expression of genes for transport of arginine and synthesis of polyamines. BPA reduced proliferation ...
Effects of BPA on expression of apoptotic genes and migration of ovine trophectoderm (oTr1) cells during the peri-implantation period of pregnancy

Elmetwally, Mohammed A.; Halawa, Amal A.; Lenis, Yaser Y.; Tang, Wanjin; Wu, Guoyao; Bazer, Fuller W. (2019)

Bisphenol A (BPA) is an endocrine-disrupting chemical used in the manufacture of many products used daily. In the present study, the effects of BPA (1 × 10 −4 to 1 × 10 -9 M) on migration and on the expression of some ...
Functional roles of agmatinase during the peri-implantation period of pregnancy in sheep

Lenis, Yasser Y.; Elmetwally, Mohammed A.; Tang, Wanjin; Satterfield, Carey; Dunlap, Kathrin; Wu, Guoyao; Bazer, Fuller W. (2018)

This study investigated the effect of agmatine (Agm) in proliferation of ovine trophecdoderm cells (oTr1) as well as the importance of the arginine decarboxylase (ADC) and agmatinase (AGMAT) alternative pathway for synthesis ...
Functional roles of ornithine decarboxylase and arginine decarboxylase during the peri-implantation period of pregnancy in sheep

Lenis, Yasser Y.; Johnson, Gregory A.; Wang, Xiaoqiu; Tang, Wendy W.; Dunlap, Kathrin A.; Satterfield, M. Carey; Wu, Guoyao; Hansen, Thomas R.; Bazer, Fuller W. (2018)

Background: Polyamines stimulate DNA transcription and mRNA translation for protein synthesis in trophectoderm cells, as well as proliferation and migration of cells; therefore, they are essential for development and ...
Physiological importance of polyamines

Lenis, Yasser Y.; Elmetwally, Mohammed A.; Maldonado-Estrada, Juan G.; Bazer, Fuller W. (2017)

Polyamines are polycationic molecules that contain two or more amino groups (-NH3 +) and are present in all eukaryotic and prokaryotic cells. Polyamines are synthesized from arginine, ornithine, and proline, and from ...
The vaginal and uterine blood flow changes during the ovsynch program and its impact on the pregnancy rates in Holstein dairy cows

Sharawy, Heba A.; Hegab, AbdelRaouf O.; Engy F., Risha; Mohamed, El‑Adl; Fahmy, Reham A.; Farag, Virginia M.; Gohar, Mohamed A.; Soliman, Walid T.; Imakawa, Kazuhiko; Bazer, Fuller W.; James, Daniela; Zaghloul, Adel (2022)

Aim OvSynch is a hormonal protocol for synchronization of estrus and use of artificial insemination (AI) at an optimal time without adverse effects on the ovaries or uterus. This study investigated the use of noninvasive ...

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Effects of Bisphenol-A on proliferation and expression of genes related to synthesis of polyamines, interferon tau and insulin-like growth factor 2 by ovine trophectoderm cells
...
Elmetwally, Mohammed A. | 2018

This study evaluated the effects of bisphenol A (BPA) on proliferation of ovine trophectoderm (oTr1) cells, as well as expression of genes for transport of arginine and synthesis of polyamines. BPA reduced proliferation of oTr1 cells at concentrations of 1 × 10−6, 1 × 10−5, 1 × 10−4 M compared to concentrations of 0, 1 × 10−9, and 1 × 10−8 M at 24 and 96 h of culture. Lower concentrations of BPA significantly increased expression of mRNAs for agmatinase (AGMAT), arginine decarboxylase (ADC), ornithine decarboxylase (ODC1) and solute carrier family 7 member 1 (SLC7A1). Similarly, synthesis of polyamines by oTr1 cells was greatest at lower concentrations of BPA and decreased as the dose of BPA increased. Expression of mRNAs for interferon tau (IFNT) and insulin-like growth factor 2 (IGF2) by oTr1 cells was greater than for controls at 1 × 10−9 M BPA. Overall, the effects of BPA on proliferation and gene expression by oTr1 cells were highly dose-dependent.

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Effects of BPA on expression of apoptotic genes and migration of ovine trophectoderm (oTr1) cells during the peri-implantation period of pregnancy
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Elmetwally, Mohammed A. | 2019

Bisphenol A (BPA) is an endocrine-disrupting chemical used in the manufacture of many products used daily. In the present study, the effects of BPA (1 × 10 −4 to 1 × 10 -9 M) on migration and on the expression of some apoptotic genes were examined in vitro using ovine trophectoderm (oTr1) primary cell line. The results revealed that BPA at 1 × 10 −9 , 1 × 10 −8 and 1 × 10 −7 M increased migration of oTr1 cells, while 1 × 10 −6 , 1 × 10 −5 and 1 × 10 −4 M BPA decreased cell migration. Regarding apoptosis, expression of the anti-apoptotic gene Bcl-2 mRNA was greater at 1 × 10 −8 and 1 × 10 −9 M BPA and was down-regulated at 1 × 10 −4 to 1 × 10 −7 M BPA; however, expression of pro-apoptotic genes (Bax, cathepsin B, caspase-3 and c-myc) was reduced at the higher concentrations of BPA. Results of this study suggest that BPA may impair implantation by decreasing migration of oTr1 cells and inhibiting apoptosis.

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Functional roles of agmatinase during the peri-implantation period of pregnancy in sheep
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Lenis, Yasser Y. | 2018

This study investigated the effect of agmatine (Agm) in proliferation of ovine trophecdoderm cells (oTr1) as well as the importance of the arginine decarboxylase (ADC) and agmatinase (AGMAT) alternative pathway for synthesis of polyamines in ovine conceptuses during the peri-implantation period of pregnancy. Morpholino antisense oligonucleotides (MAOs) were used to inhibit translation of mRNAs for ODC1 alone, AGMAT alone, and their combination. Rambouillet ewes (N = 50) were assigned randomly to the following treatments on Day 8 of pregnancy: MAO control (n = 10); MAO-ODC1 (n = 8); MAO-ADC (n = 6); MAO-ODC1:MAO-ADC (n = 9); or MAO-ODC1:MAO-AGMAT (n = 9). Ewes were ovario-hysterectomized on Day 16 of pregnancy to obtain uterine flushings, uterine endometrium, and conceptus tissues. Inhibition of translation of both ODC1 and AGMAT resulted in 22% of ewes having morphologically and functionally normal (elongated and healthy) conceptuses designated MAO-ODC1:MAO-AGMAT (A). But, 78% of the MAO-ODC1:MAO-AGMAT ewes had morphologically and functionally abnormal (not elongated and fragmented) conceptuses designated MAO-ODC1:MAO-AGMAT (B). The pregnancy rate was less (22%; P < 0.05) for MAO-ODC1:MAO-AGMAT ewes than for MAO-control (80%), MAO-ODC1 (75%), MAO-ADC (84%), and MAO-ODC1:MAO-ADC (44%) ewes. Moreover, inhibition of translational of both ODC1 and AGMAT mRNAs increased expression of ADC, SLC22A1, SLC22A2, and SLC22A3 mRNAs, as well as abundances of agmatine, putrescine, spermindine, and spermine in conceptus tissue. However, MAO-ODC1:AGMAT(B) ewes had greater abundances of agmatine, putrescine, and spermidine and reduced amounts of spermine in uterine flushes. Thus, in vivo knockdown of translation of ODC1 and AGMAT mRNAs increased expression of genes for the synthesis and transport of polyamines in ovine conceptuses during the peri-implantation period of pregnancy.

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Functional roles of ornithine decarboxylase and arginine decarboxylase during the peri-implantation period of pregnancy in sheep
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Lenis, Yasser Y. | 2018

Background: Polyamines stimulate DNA transcription and mRNA translation for protein synthesis in trophectoderm cells, as well as proliferation and migration of cells; therefore, they are essential for development and survival of conceptuses (embryo/fetus and placenta). The ovine conceptus produces polyamines via classical and non-classical pathways. In the classical pathway, arginine (Arg) is transformed into ornithine, which is then decarboxylated by ornithine decarboxylase (ODC1) to produce putrescine which is the substrate for the production of spermidine and spermine. In the non-classical pathway, Arg is converted to agmatine (Agm) by arginine decarboxylase (ADC), and Agm is converted to putrescine by agmatinase (AGMAT). Methods: Morpholino antisense oligonucleotides (MAOs) were designed and synthesized to inhibit translational initiation of the mRNAs for ODC1 and ADC, in ovine conceptuses. Results: The morphologies of MAO control, MAO-ODC1, and MAO-ADC conceptuses were normal. Double knockdown of ODC1 and ADC (MAO-ODC1:ADC) resulted in two phenotypes of conceptuses; 33% of conceptuses appeared to be morphologically and functionally normal (phenotype a) and 67% of the conceptuses presented an abnormal morphology and functionality (phenotype b). Furthermore, MAO-ODC1:ADC (a) conceptuses had greater tissue concentrations of Agm, putrescine, and spermidine than MAO control conceptuses, while MAO-ODC1:ADC (b) conceptuses only had greater tissue concentrations of Agm. Uterine flushes from ewes with MAO-ODC1:ADC (a) had greater amounts of arginine, aspartate, tyrosine, citrulline, lysine, phenylalanine, isoleucine, leucine, and glutamine, while uterine flushes of ewes with MAO-ODC1:ADC (b) conceptuses had lower amount of putrescine, spermidine, spermine, alanine, aspartate, glutamine, tyrosine, phenylalanine, isoleucine, leucine, and lysine. Conclusions: The double-knockdown of translation of ODC1 and ADC mRNAs was most detrimental to conceptus development and their production of interferon tau (IFNT). Agm, polyamines, amino acids, and adequate secretion of IFNT are critical for establishment and maintenance of pregnancy during the peri-implantation period of gestation in sheep.

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Physiological importance of polyamines
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Lenis, Yasser Y. | 2017

Polyamines are polycationic molecules that contain two or more amino groups (-NH3 +) and are present in all eukaryotic and prokaryotic cells. Polyamines are synthesized from arginine, ornithine, and proline, and from methionine as the methyl-group donor. In the traditional pathway for polyamine synthesis, arginase converts arginine into ornithine, which is decarboxylated by ornithine decarboxylase (ODC1) to generate putrescine. The latter is converted to spermidine and spermine. Recent studies have indicated the existence of 'non-classical pathways' for the generation of putrescine from arginine and proline in animal cells. Specifically, arginine decarboxylase (ADC) catalyzes the conversion of arginine into agmatine, which is hydrolyzed by agmatinase (AGMAT) to form putrescine. Additionally, proline is oxidized by proline oxidase to yield pyrroline-5-carboxylate, which undergoes transamination with glutamate to produce ornithine for decarboxylation by ODC1. Intracellular production of polyamines is controlled by antizymes binding to and inactivating ODC1. Polyamines exert effects that include stimulation of cell division and proliferation, gene expression for the survival of cells, DNA and protein synthesis, regulation of apoptosis, oxidative stress, angiogenesis, and cell-cell communication activity. Accordingly, polyamines are essential for early embryonic development and successful pregnancy outcome in mammals. In this paper the main concepts on the history, structure and molecular pathways of polyamines as well as their physiological role on angiogenesis, and reproductive physiology are reviewed. © Copyright Cambridge University Press 2017.

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The vaginal and uterine blood flow changes during the ovsynch program and its impact on the pregnancy rates in Holstein dairy cows
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Sharawy, Heba A. | 2022

Aim OvSynch is a hormonal protocol for synchronization of estrus and use of artificial insemination (AI) at an optimal time without adverse effects on the ovaries or uterus. This study investigated the use of noninvasive color Doppler ultrasound to assess changes in uterine and vaginal blood flow during the Ovsynch program for synchronization of estrus and its relation to the pregnancy rates in Holstein cows. Materials and methods The experimental cows received an intramuscular dose of 10 μg of a GnRH analogue (G1), followed 7 days later with an intramuscular injection of synthetic prostaglandin F2α (P: PGF2α) analogue (500 μg cloprostenol sodium), and given a 10 μg, injection of the GnRH analogue (G2) i.m. 48 h after the PGF2α treatment, and the cows were bred 14-16 h after. Uterine and vaginal perfusion were investigated by performing transrectal Doppler ultrasonography of both the uterine and vaginal arteries in Holstein cows at different time points during the Ovsynch program to determine: peak systolic velocity (PSV), time-averaged maximum velocity (TAMV), the volume of blood flow (BFV), pulsatility index (PI), resistance index (RI), resistance impedance (S/D) and diameters of uterine (UA) and vaginal (VA) arteries. Steroid hormones were also assayed. Transrectal ultrasonography (TUS) was performed at 32 and 60 days to confirm the pregnancy per artificial insemination (P/AI). Results The uterine PSV, TAMV, and PV were greater at the time of the cloprostenol sodium and second GnRH injections (p<0.05) than at the time of the first GnRH injection. The vaginal PSV, PV were greater at the time of the cloprostenol sodium than at the time of the first and second GnRH injections (p<0.05). The receiver operating characteristic curve (ROC curve) indicated a high correlation between the uterine and vaginal blood flow and the rate of the pregnancy (p<0.05). The area under the ROC curve was 0.920 and 0.87 (p<0.05) for vaginal and uterine arteries respectively at time of G2. The serum levels of progesterone, estrogen and cortisol were correlated with the P/AI (p<0.05). The P/AI significantly decreased from 43.9 % at 32 d to 35.37 % at 60 d. Conclusion These results indicate that noninvasive Doppler ultrasonography is a valid method to evaluate changes in the characteristics of uterine and vaginal blood flow in cows during the Ovsynch protocol. Furthermore, vaginal and uterine blood flow are two determinant factors for the higher conception rates in Holstein dairy cows.

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Browsing by Author "Bazer, Fuller W."

Effects of Bisphenol-A on proliferation and expression of genes related to synthesis of polyamines, interferon tau and insulin-like growth factor 2 by ovine trophectoderm cells ﻿

Effects of BPA on expression of apoptotic genes and migration of ovine trophectoderm (oTr1) cells during the peri-implantation period of pregnancy ﻿

Functional roles of agmatinase during the peri-implantation period of pregnancy in sheep ﻿

Functional roles of ornithine decarboxylase and arginine decarboxylase during the peri-implantation period of pregnancy in sheep ﻿

Physiological importance of polyamines ﻿

The vaginal and uterine blood flow changes during the ovsynch program and its impact on the pregnancy rates in Holstein dairy cows ﻿

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Effects of Bisphenol-A on proliferation and expression of genes related to synthesis of polyamines, interferon tau and insulin-like growth factor 2 by ovine trophectoderm cells

Effects of BPA on expression of apoptotic genes and migration of ovine trophectoderm (oTr1) cells during the peri-implantation period of pregnancy

Functional roles of agmatinase during the peri-implantation period of pregnancy in sheep

Functional roles of ornithine decarboxylase and arginine decarboxylase during the peri-implantation period of pregnancy in sheep

Physiological importance of polyamines

The vaginal and uterine blood flow changes during the ovsynch program and its impact on the pregnancy rates in Holstein dairy cows

Effects of Bisphenol-A on proliferation and expression of genes related to synthesis of polyamines, interferon tau and insulin-like growth factor 2 by ovine trophectoderm cells

Effects of BPA on expression of apoptotic genes and migration of ovine trophectoderm (oTr1) cells during the peri-implantation period of pregnancy

Functional roles of agmatinase during the peri-implantation period of pregnancy in sheep

Functional roles of ornithine decarboxylase and arginine decarboxylase during the peri-implantation period of pregnancy in sheep

Physiological importance of polyamines

The vaginal and uterine blood flow changes during the ovsynch program and its impact on the pregnancy rates in Holstein dairy cows