In Memory of Josephine Arendt

It is with great sadness that we report the sudden and unexpected death of Professor Josephine Arendt (4^th September, 2023). Jo trained as a biochemist, doing her PhD on serotonin biochemistry at the University of London. It was thus a natural progression for her to begin the early investigations into the serotonin metabolite, melatonin. She was the acknowledged expert on melatonin especially in humans, her textbook “Melatonin and the Mammalian Pineal Gland” is without peer.

Jo was internationally recognised for her enormous contribution to the field of melatonin, circadian rhythms and sleep (over 280 publications). Most of her research was conducted at the University of Surrey (1977-2023), laying the foundations for the Chronobiology and Sleep research that Surrey is renowned for today. Jo pioneered immunotechnology for the detection and measurement of melatonin and its metabolites, their circadian and seasonal response to light, and their use to characterise circadian responses particularly in conditions such as jet lag and shift work. She first described the chronobiotic properties of exogenous melatonin in relation to sleep and the circadian system and initiated its use for circadian rhythm sleep/wake disorders such as jet lag, shift work,  non-24 h sleep/wake disorder of the blind and delayed sleep phase insomnia. She characterised the importance of light and melatonin in humans pursuing research in this area particularly in Polar regions.

Frustrated by lack of funding for research, in 1988 Jo founded a company Stockgrand Ltd ( to exploit her radioimmunoassay expertise with all profits supporting research and many PhD studentships. This technology helped research worldwide and today measurement of melatonin is considered to be the most reliable biomarker of circadian clock timing.

Despite being overlooked by the male-dominated UK Royal Society and Academy of Medical Sciences, Jo achieved many honours (Fellow of the Royal College of Pathology, Fellow of the Royal Society of Medicine, Medal of St Goran’s Hospital (Karolinska Institute), Medal of Justus von Liebig University (Giessen), Ernst and Berta Scharrer Medal (University of Frankfurt), European Biological Rhythms Society Johannes Ariens Kappers Medal, and Doctor honoris causa (Medical University of Lodz, 2007). She was a founding member of the European Biological Rhythms Society (previously the European Pineal Study Group, the European Pineal Society, then the European Pineal and Biological Rhythms Society) and of the Society for Light Treatment and Biological Rhythms.  She served as the President of The European Pineal Society (1987-1990), President of the Gordon Research Conference on Pineal Cell Biology (1998-2000) and a Board Member at Large for the Society for Research on Biological Rhythms.

Jo was a true European. She collaborated with many European sleep and chronobiology laboratories, supporting Eastern European colleagues pre-1989 and mentoring many European early career researchers. She was a Francophile, fluent in French and a lover of French wine and food.   

I was fortunate to be Jo’s first postdoctoral researcher (1984) and for the past 39 years I have had the privilege to have her as a mentor, colleague and friend. She was my guiding star! Her kindness and generosity both academically and socially were much appreciated by many colleagues. She had a warm, caring nature and her joie de vivre was infectious.

To get a flavour of Jo’s intelligence and personality, you may listen to these clips from the History of Modern Biomedicine here http://www.histmodbiomed.org/article/josephine-arendt.html and from Physiological Society (video below).

The field has lost one of its shining stars. A pioneer, a trail blazer!

Condolence Book: https://rememberancebook.net/book/professor-josephine-arendt/