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Dive into the research topics where James W. Akin is active.

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Featured researches published by James W. Akin.


Biology of Reproduction | 2013

Ovarian Expression, Localization, and Function of Tissue Inhibitor of Metalloproteinase 3 (TIMP3) During the Periovulatory Period of the Human Menstrual Cycle

Katherine L. Rosewell; Feixue Li; Muraly Puttabyatappa; James W. Akin; Mats Brännström; Thomas E. Curry

ABSTRACT Ovulation involves reorganization of the extracellular matrix of the follicle. This study examines the expression, localization, and potential function of the tissue inhibitor of metalloproteinase 3 (TIMP3) during ovulation in women. The dominant follicle of the menstrual cycle was collected at specified times throughout the ovulatory process: pre-, early, late, and postovulatory. For quantitative studies, the follicle was bisected; granulosa and theca cells were separated and collected. For immunohistochemistry (IHC), the intact follicle was embedded and TIMP3 was localized. Additionally, granulosa cells were collected from women undergoing in vitro fertilization and treated with increasing concentrations of recombinant TIMP3, and cell viability was assessed. Real-time PCR for TIMP3 mRNA revealed an increase in TIMP3 mRNA expression in granulosa cells from the early to the late ovulatory stage. Thecal TIMP3 mRNA expression was constitutive across the periovulatory period. TIMP3 protein was localized by IHC to the granulosa and theca cell layers in pre-, early, and late ovulatory follicles as well as to the vascular bed. The staining was most intense in the granulosa and theca cells in the late ovulatory group. Treatment of human granulosa-lutein cells with exogenous recombinant TIMP3 for 24 h decreased cell viability by 60%. Using human follicles collected throughout the periovulatory period of the menstrual cycle, we have demonstrated that TIMP3 mRNA expression increases and that TIMP3 protein is in the appropriate cellular layers to regulate proteolytic remodeling as the follicle progresses toward ovulation. In addition, we have shown that elevated levels of TIMP3 lead to decreased cell viability.


Fertility and Sterility | 1993

The use of clomiphene citrate in the treatment of azoospermia secondary to incomplete androgen resistance

James W. Akin

An infertile male with a deletion within the AR gene is discussed. The patient presented with azoospermia and, after daily CC treatment, was found to have sperm within his ejaculate. However, the ultimate goal of pregnancy was not achieved, nor were there enough sperm present to warrant an IVF attempt.


Endocrinology | 2015

Chemokine Ligand 20: A Signal for Leukocyte Recruitment During Human Ovulation?

Linah Al-Alem; Muraly Puttabyatappa; Kathy Rosewell; Mats Brännström; James W. Akin; Jeffrey Boldt; Ken N. Muse; Thomas E. Curry

Ovulation is one of the cornerstones of female fertility. Disruption of the ovulatory process results in infertility, which affects approximately 10% of couples. Using a unique model in which the dominant follicle is collected across the periovulatory period in women, we have identified a leukocyte chemoattractant, chemokine ligand 20 (CCL20), in the human ovary. CCL20 mRNA is massively induced after an in vivo human chorionic gonadotropin (hCG) stimulus in granulosa (>10 000-fold) and theca (>4000-fold) cells collected during the early ovulatory (12-18 h) and late ovulatory (18-34 h) periods after hCG administration. Because the LH surge sets in motion an inflammatory reaction characterized by an influx of leukocytes and CCL20 is known to recruit leukocytes in other systems, the composition of ovarian leukocytes (CD45+) containing the CCL20 receptor CCR6 was determined immediately prior to ovulation. CD45+/CCR6+ cells were primarily natural killer cells (41%) along with B cells (12%), T cells (11%), neutrophils (10%), and monocytes (9%). Importantly, exogenous CCL20 stimulated ovarian leukocyte migration 59% within 90 minutes. Due to the difficulties in obtaining human follicles, an in vitro model was developed using granulosa-lutein cells to explore CCL20 regulation. CCL20 expression increased 40-fold within 6 hours after hCG, was regulated partially by the epithelial growth factor pathway, and was positively correlated with progesterone production. These results demonstrate that hCG dramatically increases CCL20 expression in the human ovary, that ovarian leukocytes contain the CCL20 receptor, and that CCL20 stimulates leukocyte migration. Our findings raise the prospect that CCL20 may aid in the final ovulatory events and contribute to fertility in women.


Fertility and Sterility | 2015

Induction of proteinases in the human preovulatory follicle of the menstrual cycle by human chorionic gonadotropin

Katherine L. Rosewell; Linah Al-Alem; Farnosh Zakerkish; Lauren McCord; James W. Akin; Charles L. Chaffin; Mats Brännström; Thomas E. Curry

OBJECTIVE To explore the temporal expression in granulosa and theca cells of key members of the MMP and ADAMTS families across the periovulatory period in women to gain insight into their possible roles during ovulation and early luteinization. DESIGN Experimental prospective clinical study and laboratory-based investigation. SETTING University medical center and private IVF center. ANIMAL AND PATIENT(S) Thirty-eight premenopausal women undergoing surgery for tubal ligation and six premenopausal women undergoing assisted reproductive techniques. INTERVENTION(S) Administration of hCG and harvesting of follicles by laparoscopy and collection of granulosa-lutein cells at oocyte retrieval. MAIN OUTCOME MEASURE(S) Expression of mRNA for matrix metalloproteinase (MMPs) and the A disintegrin and metalloproteinase with thrombospondin-like motifs (ADAMTS) in human granulosa cells and theca cells collected across the periovulatory period of the menstrual cycle and in cultured granulosa-lutein cells after hCG. Localization of MMPs and ADAMTSs by immunohistochemistry. RESULT(S) Expression of MMP1 and MMP19 mRNA increased in both granulosa and theca cells after hCG administration. ADAMTS1 and ADAMTS9 mRNA increased in granulosa cells after hCG treatment, however, thecal cell expression for ADAMTS1 was unchanged, while ADAMTS9 expression was decreased. Expression of MMP8 and MMP13 mRNA was unchanged. Immunohistochemistry confirmed the localization of MMP1, MMP19, ADAMTS1, and ADAMTS9 to the granulosa and thecal cell layers. CONCLUSION(S) The collection of the dominant follicle throughout the periovulatory period has allowed the identification of proteolytic remodeling enzymes in the granulosa and theca compartments that may be critically involved in human ovulation. These proteinases may work in concert to regulate breakdown of the follicular wall and release of the oocyte.


The Journal of Clinical Endocrinology and Metabolism | 2017

Coordinated Regulation Among Progesterone, Prostaglandins, and EGF-Like Factors in Human Ovulatory Follicles

Yohan Choi; Kalin Wilson; Patrick R. Hannon; Katherine L. Rosewell; Mats Brännström; James W. Akin; Thomas E. Curry; Misung Jo

Context: In animal models, the luteinizing hormone surge increases progesterone (P4) and progesterone receptor (PGR), prostaglandins (PTGs), and epidermal growth factor (EGF)–like factors that play essential roles in ovulation. However, little is known about the expression, regulation, and function of these key ovulatory mediators in humans. Objective: To determine when and how these key ovulatory mediators are induced after the luteinizing hormone surge in human ovaries. Design and Participants: Timed periovulatory follicles were obtained from cycling women. Granulosa/lutein cells were collected from in vitro fertilization patients. Main Outcome Measures: The in vivo and in vitro expression of PGR, PTG synthases and transporters, and EGF-like factors were examined at the level of messenger RNA and protein. PGR binding to specific genes was assessed. P4 and PTGs in conditioned media were measured. Results: PGR, PTGS2, and AREG expressions dramatically increased in ovulatory follicles at 12 to 18 hours after human chorionic gonadotropin (hCG). In human granulosa/lutein cell cultures, hCG increased P4 and PTG production and the expression of PGR, specific PTG synthases and transporters, and EGF-like factors, mimicking in vivo expression patterns. Inhibitors for P4/PGR and EGF-signaling pathways reduced hCG-induced increases in PTG production and the expression of EGF-like factors. PGR bound to the PTGS2, PTGES, and SLCO2A1 genes. Conclusions: This report demonstrated the time-dependent induction of PGR, AREG, and PTGS2 in human periovulatory follicles. In vitro studies indicated that collaborative actions of P4/PGR and EGF signaling are required for hCG-induced increases in PTG production and potentiation of EGF signaling in human periovulatory granulosa cells.


Biology of Reproduction | 2017

The expression of CXCR4 is induced by the luteinizing hormone surge and mediated by progesterone receptors in human preovulatory granulosa cells

Yohan Choi; Ji Yeon Park; Kalin Wilson; Katherine L. Rosewell; Mats Brännström; James W. Akin; Thomas E. Curry; Misung Jo

Abstract The chemokine CXC motif ligand 12 (CXCL12) and its cognate receptor, CXCR4, have been implicated in the ovulatory process in various animal models. However, little is known about the expression and regulation of CXCL12 and CXCR4 and their functions during the ovulatory period in the human ovary. In this study, we characterized the expression patterns of CXCL12 and CXCR4 in preovulatory follicles collected before the luteinizing hormone (LH) surge and at defined hours after hCG administration in women with the regular menstrual cycle. The levels of mRNA and protein for CXCR4 were increased in granulosa cells of late ovulatory follicles, whereas CXCL 12 expression was constant in follicles throughout the ovulatory period. Both CXCR4 and CXCL12 were localized to a subset of leukocytes around and inside the vasculature of human preovulatory follicles. Using a human granulosa cell culture model, the regulatory mechanisms and functions of CXCL12 and CXCR4 expression were investigated. Human chorionic gonadotropin (hCG) stimulated CXCR4 expression, whereas CXCL 12 expression was not affected, mimicking in vivo expression patterns. Both RU486 (progesterone receptor antagonist) and CoCl2 (HIFs activator) blocked the hCG-induced increase in CXCR4 expression, whereas AG1478 (EGFR inhibitor) had no effect. The treatment with CXCL12 had no effect on granulosa cell viability but decreased hCG-stimulated CXCR4 expression. Summary Sentence In conclusion, these results suggest that the CXCL12/CXCR4 system plays a role(s) in the LH surgeinduced follicular changes and infiltration of leukocytes in dominant follicles during the ovulatory period in humans.


American Journal of Obstetrics and Gynecology | 1990

Increasing quantity of maternal immunoglobulin Gin trophoblastic tissue before the onset of normal labor

James W. Akin; Wayne B. Conover; Paul D. DePriest

While levels of maternal immunoglobulin G (IgG) increase in the fetal circulation during the third trimester, actual trophoblastic concentrations have not been extensively studied. To investigate this process, placentas from 71 patients with gestational ages between 26 and 42 weeks were examined by means of a peroxidase-antiperoxidase immunostaining technique specific for IgG. Linear regression revealed a significant increase in antibody with advancing gestational age (r = 0.36, p less than 0.01). In addition, placentas from patients in spontaneous term labor revealed a significantly higher antibody level when compared with those of patients at term delivered electively before the onset of labor (mean +/- SEM 2.6 +/- 0.2 vs 1.7 +/- 0.3, p less than 0.02). Patients in premature labor failed to demonstrate this increase in antibody staining. One possible explanation for these findings is an enhanced recognition of the fetal trophoblastic tissue by the maternal immune system at term. It also suggests immunologic factors may play an important role in the initiation of normal labor.


The Journal of Clinical Endocrinology and Metabolism | 2018

FOS, a Critical Downstream Mediator of PGR and EGF Signaling Necessary for Ovulatory Prostaglandins in the Human Ovary

Yohan Choi; Katherine L. Rosewell; Mats Brännström; James W. Akin; Thomas E. Curry; Misung Jo

Context Fos null mice failed to ovulate and form a corpus luteum (CL) even when given exogenous gonadotropins, suggesting that ovarian Fos expression is critical for successful ovulation and CL formation. However, little is known about FOS in the human ovary. Objectives To determine the expression, regulation, and function of FOS in human periovulatory follicles. Design/Participants Timed periovulatory follicles were obtained from normally cycling women. Granulosa/lutein cells were collected from in vitro fertilization patients. Main Outcome Measures The in vivo expression after human chorionic gonadotropin (hCG) administration and in vitro regulation of FOS, JUN, JUNB, and JUND was evaluated at the mRNA and protein level. Binding of progesterone receptor (PGR) and FOS to their target genes was assessed by chromatin immunoprecipitation analyses. Prostaglandin E2 (PGE2) and progesterone were measured. Results The expression of FOS, JUNB, and JUND drastically increased in ovulatory follicles after hCG administration. In human granulosa/lutein cell cultures, hCG increased the expression of FOS and JUN proteins. Inhibitors of PGR and epidermal growth factor (EGF) receptors reduced hCG-induced increases in the expression and phosphorylation of FOS. PGR bound to the FOS gene. A selective FOS inhibitor blocked hCG-induced increases in PGE2 and the expression of prostaglandin (PG) synthases and transporters (PTGES, SLCO2A1, and ABCC1). FOS bound to the promoter regions of these genes. Conclusions The increase of FOS/activator protein 1 in human periovulatory follicles after hCG administration is mediated by collaborative actions of PGR and EGF signaling and critical for the upregulated expression of key ovulatory genes required for the rise in ovulatory PG in human granulosa cells.


Endocrinology | 2018

Ovulatory Induction of SCG2 in Human, Nonhuman Primate, and Rodent Granulosa Cells Stimulates Ovarian Angiogenesis

Patrick R. Hannon; Diane M. Duffy; Katherine L. Rosewell; Mats Brännström; James W. Akin; Thomas E. Curry

The luteinizing hormone (LH) surge is essential for ovulation, but the intrafollicular factors induced by LH that mediate ovulatory processes (e.g., angiogenesis) are poorly understood, especially in women. The role of secretogranin II (SCG2) and its cleaved bioactive peptide, secretoneurin (SN), were investigated as potential mediators of ovulation by testing the hypothesis that SCG2/SN is induced in granulosa cells by human chorionic gonadotropin (hCG), via a downstream LH receptor signaling mechanism, and stimulates ovarian angiogenesis. Humans, nonhuman primates, and rodents were treated with hCG in vivo resulting in a significant increase in the messenger RNA and protein levels of SCG2 in granulosa cells collected early during the periovulatory period and just prior to ovulation (humans: 12 to 34 hours; monkeys: 12 to 36 hours; rodents: 4 to 12 hours post-hCG). This induction by hCG was recapitulated in an in vitro culture system utilizing granulosa-lutein cells from in vitro fertilization patients. Using this system, inhibition of downstream LH receptor signaling pathways revealed that the initial induction of SCG2 is regulated, in part, by epidermal growth factor receptor signaling. Further, human ovarian microvascular endothelial cells were treated with SN (1 to 100 ng/mL) and subjected to angiogenesis assays. SN significantly increased endothelial cell migration and new sprout formation, suggesting induction of ovarian angiogenesis. These results establish that SCG2 is increased in granulosa cells across species during the periovulatory period and that SN may mediate ovulatory angiogenesis in the human ovary. These findings provide insight into the regulation of human ovulation and fertility.


Obstetrics & Gynecology | 2015

Transporting Vitrified Murine Oocytes Reduces Their Overall Survival on Thawing [158]

MacKenzie P. Purdy; James W. Akin; Sarah Atkinson; Jeffrey Boldt

INTRODUCTION: Vitrification is the standard of care for freezing oocytes and survival rates of thawed oocytes have increased compared with the older method of slow freezing. The objective is to identify if by forming a glassy state induced with vitrification, are the oocytes at greater risk for microarray fracturing with shipment? MATERIALS AND METHOD: Eighty mouse eggs were commercially obtained, thawed, vitrified, then divided into two groups where group 1 (study) was placed in a vapor nitrogen shipper and carried around in a vehicle for 1 week. Group 2 (control) was placed in a separate shipper but was never moved from the laboratory. All oocytes were thawed and then examined for viability. To reduce costs, reused CryoLeafs were used in each group with placement of six to seven oocytes on each straw, which increased the time necessary to complete freezing and thawing. RESULTS: Of the 80 mouse oocytes, 73 survived the initial thaw and then were refrozen. In group 1 (study), 10 of 36 (27%) survived the second thaw and in group 2 (control), 20 of 37 (54%) survived the second thaw. These differences were significant by &khgr;2 analysis with P<.05. CONCLUSION: The transport of vitrified mouse oocytes lowers overall survival on thawing and the oocytes may be more susceptible to damage from transport because of the induced glass-like state. The low percentage of eggs surviving in each group was the result of many factors including the fact that increased number of oocytes on each Cryoleaf required extra time to freeze and thaw, which led to the overall low survival.

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Jeffrey Boldt

Georgia Regents University

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Misung Jo

University of Kentucky

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Yohan Choi

University of Kentucky

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