The first of a series of papers that have developed from Lujain Almousa’s PhD studies has been published in Magnesium Research.
Given a possible anti-inflammatory role of magnesium in endothelial cells, the aim of this study was to investigate the effects of magnesium on human umbilical vein endothelial cell (HUVEC) viability, gene expression, and the pro-inflammatory response caused by a bacterial endotoxin (LPS). HUVECs were cultured at three different concentrations of magnesium sulphate (0.1 mM; control-1 mM; 5 mM) for 72 hours. Exposing the cells to LPS reduced cell viability in culture with low magnesium, but high magnesium protected the HUVECs from LPS-induced cell death. LPS-treated HUVECs cultured in low magnesium showed up-regulation of mRNA expression for pro-inflammatory factors and the expression of cytokine proteins, including IL-2, IL-3, IL-8, IL-15 and MCP-1. This was associated with greater adhesion of monocytes to the cells. In contrast, high magnesium decreased the expression of inflammatory factors and cytokines. The study found that LPS activation of the expression of many pro-inflammatory factors is exacerbated in the presence of low magnesium concentration whilst a high magnesium concentration partly inhibited the inflammatory response to LPS.
For a long time this blog has been known as The Langley-Evans Lab, which on reflection is a terribly arrogant pronouncement. What I wanted to write about on these pages was the work that I have been doing with my PhD students and colleagues and to reflect on the bricks that our work has contributed to that big wall of human knowledge.
That work isn’t the product of ‘my lab’, or ‘my team’, it’s a product of collaboration and working together. Some of the ideas have been mine, I’ve generated some of the data myself but all of the papers and grant ideas are shared with the many, many PhD students, the postdocs and the collaborators that I’ve had along the way.
As my research moves on, I don’t rely solely on a lab anymore either. We’re published qualitative as well as quantitative date. We’re gathering data from out in the field in Botswana, Uganda, Malawi, Ethiopia and South Africa. The rat study days are largely coming to an end- things are very different to the early days.
So, a new and more inclusive title was needed for the blog and so I came up with ‘One day we will look back on all of this and laugh”. It suits my current mood and it’s something that I often find myself saying at home. It’s a response to the many challenges that life throws ups at home (I own teenagers and my parents are increasingly frail and vulnerable) and at work. Academic life can be so tough- a constant rollercoaster of rejections, terribly rude and dismissive reviewers (and sometimes colleagues) and challenging targets to meet. My resilience is sometimes tested to the absolute limits.
But one day, we will look back on all of this and laugh,
On the 13th July the School of Biosciences had it’s summer Graduation ceremony. The Division of Nutritional Sciences had a bumper haul of PhD’s graduating, and I was particularly pleased to see four of my own students crossing the stage to accept their certificates. Lujain, Grace, Paphani and Bashair all followed very different directions with their research and led me off into new areas that I will be sure to follow up on.
It was great to catch up with them all and meet their families.
Photo by Andy Salter
Former PhD student Lujain Almousa (on right in picture, graduated July 2018) has had her first paper accepted for publication in Magnesium Research. The paper, entitled, ‘Varying magnesium concentration elicits changes in inflammatory response in human umbilical vein endothelial cells (HUVECs)‘ is the first in a series of three papers arising from her PhD project, which has given some interesting insights into the impact of magnesium on the function of the vascular endothelium.
The abstract of the paper is below.
The aims of this study were to determine whether low concentrations of magnesium invitroexacerbatedthe human umbilical vein endothelial cell (HUVEC) response to inflammatory challenge, and whether expressionof the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) through the toll-like receptor 4 (TLR4) played a role in this process. HUVECs were incubated with different concentrations of Mg (low- 0.1mM, control- 1mM, high- 5mM) for 72 h before being stimulated with bacterial lipopolysaccharide (LPS) for 4 h. The response of cells to LPS was greater in cells cultured in low Mg, relative to control cells and suppressed in high Mg. Expression of NF-κB was increased in low-Mg and decreased with high Mg. Low Mg increased the expression of TLR4 mRNA, but only in the presence of LPS. Antibody blockade of TLR4 but not TLR2 blunted the reponse of cells to LPS in low Mg, such that they were similar to unblocked 1mM Mg cells. Associations of Mg with cardiovascular disease may therefore relate to inflammatory responses mediated through the TLR4/NF-κB pathway.
We are delighted to welcome Ellen Ward as a new PhD student. Ellen will be starting on October 1st and will be a part of the University of Nottingham-Adelaide joint PhD partnership programme. Like Sally Draycott, Ellen will be co-supervised by myself and Matt Elmes in the UK and Bev Muhlhausler in Adelaide. Her project is entitled, ‘maternal diet and the composition of breast milk: impact of reducing sugar and fat consumption’.
We have a couple of new book chapters out this month, which are the first fruits of the collaboration between my lab and that of Bev Muhlhausler in Adelaide.
Langley-Evans SC, Muhlhausler BS (2017). Early nutrition, epigenetics and health. Chapter 11, in: Epigenetics of Aging and Lonvegity Eds: Moskalev A and Vaiserman A.
Muhlhausler BS, Gugusheff J, Langley-Evans SC (2017). Maternal junk food diets: The effects on offspring fat mass and food preferences. In: Diet, Nutrition and Fetal Programming From Womb to Adulthood, Ed: Patel VB, Preedy VR and Rajendram R. pp 227-238.
Our new paper on infant malnutrition in Botswana is now available online. The paper examines levels of stunting, wasting and underweight in infants aged 6-24 months recruited in four regions of the country. Participants were grouped according to HIV status of the mothers, giving a population of infants not exposed to HIV and infants who were not themselves HIV infected, but whose mothers were HIV positive. We found that HIV-exposed infants were more likely to be underweight and stunted and that these children were also predominantly formula fed. Factors relating to the environment before birth also had a clear impact upon risk of malnutrition.
Birthweight, HIV exposure and infant feeding as predictors of malnutrition in Botswanan infants
Chalashika et al., JHND Early View
A better understanding of the nutritional status of infants who are HIV-Exposed-Uninfected (HEU) and HIV-Unexposed-Uninfected (HUU) during their first 1000 days is key to improving population health, particularly in sub-Saharan Africa.
A cross-sectional study compared the nutritional status, feeding practices and determinants of nutritional status of HEU and HUU infants residing in representative selected districts in Botswana during their first 1000 days of life. Four hundred and thirteen infants (37.3% HIV-exposed), aged 6–24 months, attending routine child health clinics, were recruited. Anthropometric, 24-h dietary intake and socio-demographic data was collected. Anthropometric Z-scores were calculated using 2006 World Health Organization growth standards. Modelling of the determinants of malnutrition was undertaken using logistic regression.
Overall, the prevalences of stunting, wasting and being underweight were 10.4%, 11.9% and 10.2%, respectively. HEU infants were more likely to be underweight (15.6% versus 6.9%), (P < 0.01) and stunted (15.6% versus 7.3%), (P < 0.05) but not wasted (P = 0.14) than HUU infants. HEU infants tended to be formula fed (82.5%), whereas HUU infants tended to breastfeed (94%) for the first 6 months (P < 0.001). Significant predictors of nutritional status were HIV exposure, birthweight, birth length, APGAR (appearance, pulse, grimace, activity and respiration) score and mother/caregiver’s education with little influence of socio-economic status.
HEU infants aged 6–24 months had worse nutritional status compared to HUU infants. Low birthweight was the main predictor of undernutrition in this population. Optimisation of infant nutritional status should focus on improving birthweight. In addition, specific interventions should target HEU infants aiming to eliminate growth disparity between HEU and HUU infants.