213 research outputs found
New advances in reproductive biomedicine
EditorialIrma Virant-Klun, Jeroen Krijgsveld, John Huntriss and Raymond J. Rodger
Morphometric analyses and gene expression related to germ cells, gonadal ridge epithelial-like cells and granulosa cells during development of the bovine fetal ovary
Cells on the surface of the mesonephros give rise to replicating Gonadal Ridge Epithelial-Like (GREL) cells, the first somatic cells of the gonadal ridge. Later germ cells associate with the GREL cells in the ovigerous cords, and the GREL cells subsequently give rise to the granulosa cells in follicles. To examine these events further, 27 bovine fetal ovaries of different gestational ages were collected and prepared for immunohistochemical localisation of collagen type I and Ki67 to identify regions of the ovary and cell proliferation, respectively. The non-stromal cortical areas (collagen-negative) containing GREL cells and germ cells and later in development, the follicles with oocytes and granulosa cells, were analysed morphometrically. Another set of ovaries (n = 17) were collected and the expression of genes associated with germ cell lineages and GREL/granulosa cells were quantitated by RT-PCR. The total volume of non-stromal areas in the cortex increased significantly and progressively with ovarian development, plateauing at the time the surface epithelium developed. However, the proportion of non-stromal areas in the cortex declined significantly and progressively throughout gestation, largely due to a cessation in growth of the non-stroma cells and the continued growth of stroma. The proliferation index in the non-stromal area was very high initially and then declined substantially at the time follicles formed. Thereafter, it remained low. The numerical density of the non-stromal cells was relatively constant throughout ovarian development. The expression levels of a number of genes across gestation either increased (AMH, FSHR, ESR1, INHBA), declined (CYP19A1, ESR2, ALDH1A1, DSG2, OCT4, LGR5) or showed no particular pattern (CCND2, CTNNB1, DAZL, FOXL2, GATA4, IGFBP3, KRT19, NR5A1, RARRES1, VASA, WNT2B). Many of the genes whose expression changed across gestation, were positively or negatively correlated with each other. The relationships between these genes may reflect their roles in the important events such as the transition of ovigerous cords to follicles, oogonia to oocytes or GREL cells to granulosa cells.Katja Hummitzsch, Nicholas Hatzirodos, Helen F. Irving-Rodgers, Monica
D. Hartanti, Viv E. A. Perry, Richard A. Anderson, Raymond J. Rodger
Candidate genes for polycystic ovary syndrome are regulated by TGFβ in the bovine foetal ovary
Vol. 37(6) pp 1244-1254STUDY QUESTION: Could changes in transforming growth factor b (TGFb) signalling during foetal ovary development alter the expression of polycystic ovary syndrome (PCOS) candidate genes leading to a predisposition to PCOS? SUMMARY ANSWER: TGFb signalling molecules are dynamically expressed during foetal ovary development and TGFb1 inhibits expression of the androgen receptor (AR) and 7 (INSR, C8H9orf3, RAD50, ERBB3, NEIL2, IRF1 and ZBTB16) of the 25 PCOS candidate genes in foetal ovarian fibroblasts in vitro, whilst increasing expression of the AR cofactor TGFb-induced transcript 1 (TGFB1I1 or Hic5). WHAT IS KNOWN ALREADY: The ovarian stroma arises from the mesonephros during foetal ovary development. Changes in the morphology of the ovarian stroma are cardinal features of PCOS. The ovary is more fibrous and has more tunica and cortical and subcortical stroma. It is not known why this is and when this arises. PCOS has a foetal origin and perhaps ovarian stroma development is altered during foetal life to determine the formation of a polycystic ovary later in life. PCOS also has a genetic origin with 19 loci containing 25 PCOS candidate genes. In many adult tissues, TGFb is known to stimulate fibroblast replication and collagen deposition in stroma, though it has the opposite effect in the non-scaring foetal tissues. Our previous studies showed that TGFb signalling molecules [TGFbs and their receptors, latent TGFb binding proteins (LTBPs) and fibrillins, which are extracellular matrix proteins that bind LTBPs] are expressed in foetal ovaries. Also, we previously showed that TGFb1 inhibited expression of AR and 3 PCOS candidate genes (INSR, C8H9orf3 and RAD50) and stimulated expression of TGFB1I1 in cultured foetal ovarian fibroblasts. STUDY DESIGN, SIZE, DURATION: We used Bos taurus for this study as we can ethically collect foetal ovaries from across the full 9-month gestational period. Foetal ovaries (62–276 days, n ¼ 19) from across gestation were collected from pregnant B. taurus cows for RNA-sequencing (RNA-seq) analyses. Foetal ovaries from B. taurus cows were collected (160–198 days, n ¼ 6) for culture of ovarian fibroblasts. PARTICIPANTS/MATERIALS, SETTING, METHODS: RNA-seq transcriptome profiling was performed on foetal ovaries and the data on genes involved in TGFb signalling were extracted. Cells were dispersed from foetal ovaries and fibroblasts cultured and treated with TGFb1. The effects of TGFb regulation on the remaining eight PCOS candidate genes not previously studied (ERBB3, MAPRE1, FDFT1, NEIL2, ARL14EP, PLGRKT, IRF1 and ZBTB16) were examined. MAIN RESULTS AND THE ROLE OF CHANCE: Many TGFb signalling molecules are expressed in the foetal ovary, and for most, their expression levels increased accross gestation (LTBP1/2/3/4, FBN1, TGFB2/3, TGFBR2/3 and TGFB1I1), while a few decreased (FBN3, TGFBR3L, TGFBI and TGFB1) and others remained relatively constant (TGFBRAP1, TGFBR1 and FBN2). TGFb1 significantly decreased expression of PCOS candidate genes ERBB3, NEIL2, IRF1 and ZBTB16 in cultured foetal ovarian fibroblasts. LARGE SCALE DATA: The FASTQ files, normalized data and experimental information have been deposited in the Gene Expression Omnibus (GEO) accessible by accession number GSE178450.LIMITATIONS, REASONS FOR CAUTION: Regulation of PCOS candidate genes by TGFb was carried out in vitro and further studies in vivo are required. This study was carried out in bovine where foetal ovaries from across all of the 9-month gestational period were available, unlike in the human where it is not ethically possible to obtain ovaries from the second half of gestation. WIDER IMPLICATIONS OF THE FINDINGS: From our current and previous results we speculate that inhibition of TGFb signalling in the foetal ovary is likely to (i) increase androgen sensitivity by enhancing expression of AR, (ii) increase stromal activity by stimulating expression of COL1A1 and COL3A1 and (iii) increase the expression of 7 of the 25 PCOS candidate genes. Thus inhibition of TGFb signalling could be part of the aetiology of PCOS or at least the aetiology of polycystic ovaries. STUDY FUNDING/COMPETING INTEREST(S): Funding was received from Adelaide University China Fee Scholarship (M.L.), Australian Research Training Program (R.A.) and the Faculty of Health and Medical Science Divisional Scholarship (R.A.), Adelaide Graduate Research Scholarships (R.A. and N.A.B.), Australia Awards Scholarship (M.D.H.), Robinson Research Institute Career Development Fellowship (K.H.) and Building On Ideas Grant (K.H.), National Health and Medical Research Council of Australia Centre for Research Excellence in the Evaluation, Management and Health Care Needs of Polycystic Ovary Syndrome (N.A.B., M.D.H. and R.J.R.; GTN1078444) and the Centre for Research Excellence on Women’s Health in Reproductive life (R.A., R.J.R. and K.H.; GTN1171592) and the UK Medical Research Council (R.A.A.; grant no. G1100357). The funders did not play any role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. The authors of this manuscript have nothing to declare and no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.Rafiatu Azumah, Menghe Liu, Katja Hummitzsch, Nicole A. Bastian, Monica D. Hartanti, Helen F. Irving-Rodgers, Richard A. Anderson, and Raymond J. Rodger
The \u3ci\u3eExxon Valdez\u3c/i\u3e Reopener: Natural Resources Damage Settlements and Roads Not Taken
The 1989 Exxon Valdez oil spill caused extensive natural resource damage to the Prince William Sound. Lawsuits addressing this natural resource damage resulted in a settlement that required Exxon to pay 100 million to fund restoration or rehabilitation of resources whose injuries were not foreseeable in 1989.
This Article urges the State of Alaska and the United States to seek enforcement of the Reopener Clause, to restore natural resources and Native subsistence uses that were not addressed in the initial settlement and have not recovered from the Exxon Valdez oil spill.
Alternatively, this Article urges Native entities to intervene in the case and seek enforcement of the Reopener Clause. To date, neither Alaska nor the federal government have requested any of the $100 million Exxon may be required to pay to compensate for additional damages resulting from the oil spill.
We offer extended comment on this most famous of all natural resource damage cases. Special attention will be paid to legal roads not taken
Sequence comparisons of cytochrome P450 aromatases from Australian animals predict differences in enzymatic activity and/or efficiency
Aromatase (P450arom, CYP19A1) is the terminal enzyme in the synthesis of the steroid hormone family of estrogens. Not surprisingly, this enzyme has structural similarities between the limited number of species studied thus far. This study examined the structure of aromatases from four diverse Australian species including a marsupial (tammar wallaby; Macropus eugenii), monotreme (platypus; Ornithorhynchus anatinus), ratite (emu; Dromaius novaehollandiae) and lizard (bearded dragon; Pogona vitticeps). We successfully built homology models for each species, using the only crystallographically determined structure available, human aromatase. The amino acid sequences showed high amino acid sequence identity to the human aromatase: wallaby 81%, platypus 73%, emu 75% and bearded dragon at 74%. The overall structure was highly conserved among the five species, although there were non-secondary structures (loops and bends) that were variable and flexible that may result in some differences in catalytic activity. At the N-terminal regions there were deletions and variations that suggest functional distinctions may be found. We found that the active sites of all these proteins were identical, except for a slight variation in the emu. The electrostatic potential across the surfaces of these aromatases highlighted likely variations to the protein-protein interactions of these enzymes with both redox partner cytochrome P450 reductase and possibly homodimerization in the case of the platypus, which has been postulated for the human aromatase enzyme. Given the high natural selection pressures on reproductive strategies the relatively high degree of conservation of aromatase sequence and structure across species suggests that there is biochemically very little scope for changes to have evolved without the loss of enzyme activity.Anam Fatima, Jessica K. Holien, Chandni Tiwari, Michael W. Parker, Raymond J. Rodgers and Lisandra L. Marti
Maternal periconceptional and first trimester protein restriction in beef heifers: effects on maternal performance and early fetal growth
This study evaluated the effect of protein restriction during the periconception (PERI) and first trimester (POST) periods on maternal performance, physiology and early fetal growth. Yearling nulliparous heifers (n = 360) were individually fed a diet high or low in protein (HPeri and LPeri respectively) beginning 60 days before conception. From 24 to 98 days post-conception (dpc), half of each treatment group changed to the alternative post-conception high- or low-protein diet (HPost and LPost respectively), yielding four groups in a 2 × 2 factorial design with a common diet until parturition. Protein restriction was associated with lower bodyweight subsequent to reduced (but positive) average daily weight gain (ADG) during the PERI and POST periods. During the POST period, ADG was greater in LPeri than HPeri heifers and tended to be greater in LPost than HPost heifers during the second and third trimester. Bodyweight was similar at term. The pregnancy rate did not differ, but embryo loss between 23 and 36 dpc tended to be greater in LPeri than HPeri heifers. Overall, a greater proportion of male fetuses was detected (at 60 dpc 63.3% male vs 36.7% female). Protein restriction altered maternal plasma urea, non-esterified fatty acids, progesterone, leptin and insulin-like growth factor 1 at critical stages of fetal development. However, profiles varied depending on the sex of the conceptus.Katrina J. Copping, Andrew Hoare, I. Caroline McMillen, Raymond J. Rodgers, Charles R. Wallace and Viv E.A. Perr
Transforming growth factor beta 1 impairs the transcriptomic response to contraction in myotubes from women with polycystic ovary syndrome
First published online 27 June 2022Polycystic ovary syndrome (PCOS) is characterised by a hormonal imbalance affecting the reproductive and metabolic health of reproductive-aged women. Exercise is recommended as a first-line therapy for women with PCOS to improve their overall health; however, women with PCOSare resistant to the metabolic benefits of exercise training. Here, we aimed to gain insight into the mechanisms responsible for such resistance to exercise in PCOS. We employed an in vitro approach with electrical pulse stimulation (EPS) of cultured skeletal muscle cells to explore whether myotubes from women with PCOS have an altered gene expression signature in response to contraction.Following EPS, 4719 genes were differentially expressed (false discovery rate<0.05) in myotubes from women with PCOS compared to 173 in healthy women. Both groups included genes involved in skeletal muscle contraction. We also determined the effect of two transforming growth factorβ(TGFβ) ligands that are elevated in plasma of women with PCOS, TGFβ1 and anti-Müllerianhormone (AMH), alone and on the EPS-induced response. While AMH (30 ng/ml) had no effect,TGFβ1 (5 ng/ml) induced the expression of extracellular matrix genes and impaired the exercise-like transcriptional signature in myotubes from women with and without PCOS in response to EPS by interfering with key processes related to muscle contraction, calcium transport and actin filament.Our findings suggest that while the fundamental gene expression responses of skeletal muscle to contraction is intact in PCOS, circulating factors like TGFβ1 may be responsible for the impaired adaptation to exercise in women with PCOS.Luke C. McIlvenna, Ali Altıntas, Rhiannon K. Patten, Andrew J. McAinch, Raymond J. Rodgers, Nigel K. Stepto, Romain Barrès, and Alba Moreno-Ass
Periconception and first trimester diet modifies appetite, hypothalamic gene expression, and carcass traits in bulls
Nulliparous yearling beef heifers (n=360) were used to evaluate the effects of maternal dietary protein during the periconception and first trimester periods of gestation on postnatal growth, feedlot performance, carcass characteristics, and the expression of genes associated with appetite in the arcuate nucleus of their male progeny. Heifers were individually fed a diet of 1.18g crude protein (CP)/day High protein (HPeri) or 0.62g CP/day Low protein (LPeri) beginning 60days before conception. From 24 to 98days post-conception (dpc), half of each treatment group changed to the alternative post-conception diet and were fed 1.49g CP/day (HPost) or 0.88g CP/day (LPost) yielding four treatment groups in a 2×2 factorial design. From day 98 of gestation, heifers received a common diet until parturition. Calves were weaned at 183days and developed on pasture before feedlot entry. Bulls underwent a 70-day Residual Feed Intake (RFI) feedlot test commencing at 528days of age. Feedlot entry and final body weight (BW), feedlot average daily gain (ADG) and RFI were not different (p>0.05). Progeny of dams that had a change in diet (LPeri/HPost and HPeri/LPost) had 9% higher daily dry matter intake (DMI) during the RFI test (p<0.05) than progeny of dams that received low diet throughout both the peri-conception period and first trimester (LPeri/LPost). Further, mRNA expression of the appetite-stimulating agouti-related protein (AGRP) was increased in the arcuate nucleus of High Peri/LPost bulls (p<0.05). Longissimus dorsi muscle cross sectional area, carcass dressing percentage, and estimated retail beef yield (RBY) were all higher (p<0.05), and rump (P8) fat tended to be lower (p=0.07), for bulls from HPost dams despite no difference in carcass weight (p<0.05). This study is of commercial importance to the livestock industry as specific periods of maternal dietary supplementation may increase feed intake, enhance progeny muscling, and alter fat deposition leading to improvement in efficiency of meat production in beef cattle.Katrina J. Copping, Matthew J. Callaghan, Geert H. Geesink, Jessica R. Gugusheff, I. Caroline McMillen, Raymond J. Rodgers, Beverly S. Muhlhausler, Mini A. Vithayathil and Viv E. A. Perr
Physiologic-Based Cord Clamping Maintains Core Temperature vs. Immediate Cord Clamping in Near-Term Lambs
Background: Physiologic-based cord clamping (PBCC) involves deferring umbilical
cord clamping until after lung aeration. It is unclear if infant is at risk of becoming
hypothermic during PBCC.
Objectives: To test if PBCC would maintain core temperature more effectively than
immediate cord clamping (ICC).
Design: At 0.93 gestation, fetal lambs were surgically exteriorized and instrumented
from pregnant ewes under general anesthesia. Prior to the start of the experiment,
lambs were thoroughly dried, placed on hot water bottles, and core temperature
was continuously monitored using a rectal thermometer. PBCC lambs (n = 21),
received intermittent positive pressure ventilation (iPPV) for ≥5 min prior to umbilical
cord clamping. In ICC lambs (n = 23), iPPV commenced within 60 s after umbilical
cord clamping. iPPV was provided with heated/humidified gas. Lambs were moved
under a radiant warmer after umbilical cord clamping. Additional warmth was provided
using a plastic overlay, hairdryer, and extra water bottles, as needed. Two-way mixed
and repeated measures one-way ANOVAs were used to compare temperature changes
between and within a single group, respectively, over time.
Results: Basal fetal parameters including core temperature were similar between
groups. ICC lambs had a significant reduction in temperature compared to PBCC lambs
(p < 0.001), evident by 1 min (p = 0.002). ICC lambs decreased temperature by 0.51◦C
(± 0.42) and 0.79◦C (± 0.55) at 5 and 10 min respectively (p <
Evidence summaries and recommendations from the international evidence-based guideline for the assessment and management of polycystic ovary syndrome: assessment and treatment of infertility
STUDY QUESTION:What is the recommended assessment and management of infertile women with polycystic ovary syndrome (PCOS), based on the best available evidence, clinical expertize and consumer preference? SUMMARY ANSWER:International evidence-based guidelines, including 44 recommendations and practice points, addressed prioritized questions to promote consistent, evidence-based care and improve the experience and health outcomes of infertile women with PCOS. WHAT IS KNOWN ALREADY:Previous guidelines on PCOS lacked rigorous evidence-based processes, failed to engage consumer and multidisciplinary perspectives or were outdated. The assessment and management of infertile women with PCOS are inconsistent. The needs of women with PCOS are not being adequately met and evidence practice gaps persist. PARTICIPANTS/MATERIALS SETTING METHODS:Governance included a six continent international advisory and a project board, a multidisciplinary international guideline development group (GDG), consumer and translation committees. Extensive health professional and consumer engagement informed the guideline scope and priorities. The engaged international society-nominated panel included endocrinology, gynaecology, reproductive endocrinology, obstetrics, public health and other experts, alongside consumers, project management, evidence synthesis and translation experts. Thirty-seven societies and organizations covering 71 countries engaged in the process. Extensive online communication and two face-to-face meetings over 15 months addressed 19 prioritized clinical questions involving nine evidence-based reviews and 10 narrative reviews. Evidence-based recommendations (EBRs) were formulated prior to consensus voting within the guideline panel. STUDY DESIGN SIZE DURATION:International evidence-based guideline development engaged professional societies and consumer organizations with multidisciplinary experts and women with PCOS directly involved at all stages. A (AGREE) II-compliant processes were followed, with extensive evidence synthesis. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework was applied across evidence quality, desirable and undesirable consequences, feasibility, acceptability, cost, implementation and ultimately recommendation strength. The guideline was peer-reviewed by special interest groups across our partner and collaborating societies and consumer organizations, was independently assessed against AGREE II criteria and underwent methodological review. This guideline was approved by all members of the GDG and has been approved by the NHMRC. MAIN RESULTS AND THE ROLE OF CHANCE:The quality of evidence (QOE) for the EBRs in the assessment and management of infertility in PCOS included very low (n = 1), low (n = 9) and moderate (n = 4) quality with no EBRs based on high-quality evidence. The guideline provides 14 EBRs, 10 clinical consensus recommendations (CCRs) and 20 clinical practice points on the assessment and management of infertility in PCOS. Key changes in this guideline include emphasizing evidence-based fertility therapy, including cheaper and safer fertility management. LIMITATIONS REASONS FOR CAUTION:Overall evidence is generally of low to moderate quality, requiring significantly greater research in this neglected, yet common condition. Regional health systems vary and a process for adaptation of this guideline is provided. WIDER IMPLICATIONS OF THE FINDINGS:The international guideline for the assessment and management of infertility in PCOS provides clinicians with clear advice on best practice based on the best available evidence, expert multidisciplinary input and consumer preferences. Research recommendations have been generated and a comprehensive multifaceted dissemination and translation program supports the guideline with an integrated evaluation program. STUDY FUNDING/COMPETING INTERESTS:The guideline was primarily funded by the Australian National Health and Medical Research Council of Australia (NHMRC) supported by a partnership with ESHRE and the American Society for Reproductive Medicine (ASRM). GDG members did not receive payment. Travel expenses were covered by the sponsoring organizations. Disclosures of conflicts of interest were declared at the outset and updated throughout the guideline process, aligned with NHMRC guideline processes. Dr Costello has declared shares in Virtus Health and past sponsorship from Merck Serono for conference presentations. Prof. Norman has declared a minor shareholder interest in the IVF unit Fertility SA, travel support from Merck and grants from Ferring. Prof. Norman also has scientific advisory board duties for Ferring. The remaining authors have no conflicts of interest to declare.This article was not externally peer-reviewed by Human Reproduction Open.M F Costello, M L Misso, A Balen, J Boyle, L Devoto, R M Garad ... et al
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