Contact
Biography
I graduated from the University of Bath in 1996 with a BSc (Hons) in Biochemistry which incorporated two six-month industrial placements: (1) At the Institute of Food Research, Reading and (2) at the University of Texas Medical Branch, Galveston, Texas, USA.
After Bath University, I went on to completed my PhD in 2000 under the supervision of Professor Claire Wathes at the Royal Veterinary College, London. My PhD thesis elucidated several of the underlying mechanisms by which early pregnancy is established in the dairy cow. In 1997, I was awarded the SRF student poster prize.
I then spent two years working at Pfizer Animal Health (Sandwich, Kent) as a post-doctoral scientist on various drug discovery programmes s before joining the University of Nottingham in 2002 as a BBSRC post-doctoral researcher. Here, I worked with Professor Morag Hunter, Dr George Mann and Professor Bob Webb on 2 BBSRC-funded grants:
- Regulation of luteinisation and progesterone secretion in the bovine corpus luteum
- Identification of novel oocyte secreted proteins.
In 2006, in recognition of my work on the bovine ovary I was awarded the SRF New Investigator award.
In August 2006, I was appointed as a foundation lecturer in Reproductive Physiology at Nottingham Vet school. I have played a key role in the development and teaching of the Reproduction and Pharmacology curriculums. At the same time, I have further developed my research profile into cattle fertility. This work has been supported by the BBSRC, Society for Reproduction and Fertility and the University of Nottingham
Expertise Summary
As a Associate Professor in Reproductive Physiology and Pharmacology, I played a key role in the development of the Reproduction (Year 2) and Principles of Veterinary Sciences (Year 3) modules. Currently, I am deputy programme lead for the BVetMedSci course and module convenor for Veterinary Urogenital module. I also play an important role with teaching in basic adult cattle handling and pharmacology during the first 3 years. I also teach on the preliminary year course
Research Summary
My current research focuses on understanding the underlying mechanism behind the declining fertility in dairy cows. Worldwide, conception rates are well below 40%, a level that is unsustainable over… read more
Current Research
My current research focuses on understanding the underlying mechanism behind the declining fertility in dairy cows. Worldwide, conception rates are well below 40%, a level that is unsustainable over the long-term. With up to 40% of embryos being lost before attachment, mainly due to the inadequate secretion of progesterone from corpus luteum (CL), my research has focused on ovulatory follicle, ovulation and how the CL develops. This has involved a long-standing collaboration with Professor Morag Hunter and Dr George Mann (School of Biosciences) and funded by BBSRC and Pfizer.
The ovary is an extremely dynamic organ with one key phase being ovulation when the oocyte (egg) is released for fertilisation. The CL forms from the remnants of the ovulated follicle and grows extremely rapid, at a rate that is only rivalled by the fastest growing, most aggressive tumours. Angiogenesis is a crucial component of this rapid growth and this aspect is my primary focus. Recently, we have developed an in vitro model of luteal angiogenesis utilising primary cells from the ovary in which tubule-like structures develop and resembles an capillary bed (http://www.reproduction-online.org/content/135/3/405.long). This system has enabled us to demonstrate that fibroblast growth factor (FGF) receptor signalling is essential for these networks to form (http://www.reproduction-online.org/content/138/3/581.long). Further work show that the key step that was most sensitive to FGF blockade was the initiation of endothelial sprouting and branching. Our work has also shown that PDGF signalling and pericyte play important roles in the formation of these networks (http://www.reproduction-online.org/content/138/6/869.long).
Recently, we have completed a meta-analysis investigating the efficacy of progesterone supplementation in dairy cows. This study revealed that progesterone treatment was beneficial if it was used on naturally mated cows, cows with poor inherent fertility and if treatment was started between day 3 and 7 http://www.sciencedirect.com/science/article/pii/S0093691X15007025
Past Research
Past PhD Students
Mhairi Laird completed her PhD studies in 2010, which focused on the determining the roles of the different cell types (in particular pericytes) in regulating luteal angiogenesis. She has shown that pericytes migrate ahead of endothelial cells during CL formation and that pericyte area increased rapidly in the early stages of angiogenesis. She also developed a novel serum-free angiogenesis culture system to study formation of endothelial cell networks during luteinisation. Using this system, she demonstrated that luteal endothelial cells were more sensitive to FGF rather than VEGFA inhibition. Moreover, FGF2, but not VEGFA, was induced the precocious and more extensive sprouting of endothelial cells. http://www.reproduction-online.org/content/138/6/869.long
In 2011, Chitra Joseph completed her PhD studies with me where she investigated the regulation and function of secreted protein acidic, cysteine-rich (SPARC) in the ovary. She found that SPARC was differentially regulated during folliculogenesis but interesting was massively up-regulated in the collapsed follicle following ovulation. Further studies showed that TGFB and fibronectin, but not LH were likely candidate regulator of this. Interestingly, in the absence of low FGF2 and VEGFA, a proteolytic fragment of SPARC stimulated both luteal angiogenesis and progesterone production in vitro. http://www.reproduction-online.org/content/early/2012/06/25/REP-12-0099.long
Sotiris Propokiou in collaboration with School of Mathematical Sciences completed his PhD thesis in which he developed several in silico models of following:
I have also been awarded a Society for Reproduction and Fertility (SRF) academic grant to investigate the effects of electrical cues and influences of beta-adrenoreceptors on the formation of the CL. This involves a collaboration with Dr Christine Pullar in the University of Leicester (http://www.srf-reproduction.org/Grants/SRFAcademicScholarship/ScholarshipAwards2010.aspx)
Highlights of my research findings:
Future Research
Current and future research is focusing on the impact of diseases (e.g. endometritis and Schmallenberg virus) and nutrition on ovarian and uterine function in the cow. A particular focus will be on the how these situations affect angiogenesis and the ability of endothelial cells to form vascular networks.
I have have an interest in developing a research programme looking into progesterone supplementation in women undergoing artificial reproduction treatments.