Seminar Leoné Malan - The Brain-Heart link: a novel perspective

Seminar "The Brain-Heart Link: a novel perspective"

Date: Tuesday, 23rd February 2016 13h00 - 14h00

Where: LIH 1b, rue Thomas Edison L-1445 Strassen, Room Sanger/Snow

Speaker: Prof Leoné Malan, PhD

- Hypertension in Africa Research Team (Hart), North-West University Potchefstroom Campus, South Africa

- Medical Research Council: Research Unit for Hypertension and Cardiovascular Disease, North-West University; Potchefstroom, South Africa

Abstract
During chronic emotional taxing situations, defence responses are elicited which inevitably increase brain metabolism Defensive coping responses were related to insufficient oxygen and glucose signalling augmenting higher neural drive and hyperkinetic blood pressure responses in Africans. Ultimately, increasing sheer stress and inducing structural vascular changes. Vulnerability may therefore emerge in an over-demanding environment where efforts to take control, drain behavioural-physiological resources. Dissociation between behavioural- and physiological defensive coping responses revealed behavioural control accompanied by “loss of control” or neural and adrenal fatigue. The working hypothesis is that behavioural control may thus initially “mask” neural and cardiometabolic pathology such as an increased risk for hypertension, endothelial dysfunction and stroke. Prospective data will have to confirm if defensive coping responses will predict cardiometabolic morbidity and target organ damage. Our work highlights the need to consider psychosocial risk factors in preventive cardiology.

About the Speaker
Prof Malan commenced with research in 2007 in the Hypertension in Africa Research Team (HART). Her working hypothesis is based on 20 years plus findings of augmented vascular responses in urban-dwelling black Africans. This sparked the design of the first psychophysiological prospective cohort study in Africa, viz. the Sympathetic activity and Ambulatory Blood Pressure in Africans (SABPA) Prospective Cohort study, which received an international award for excellence (2008). Currently she participates in international meta-analyses and -projects and collaborates with international expert researchers (2007–). She conceptualized and sparked the implementation of the Hypertension Research and Training Clinic on campus (2012), where she initiated laboratory facilities and service delivery programs in collaboration with ROCHE Diagnostics and MDs. Ultimately, she is focused to develop a diagnostic tool from a stress perspective, which may contribute to early screening of cardio metabolic pathology in under- and developed countries.

Mutual interest: Luxembourg and South Africa
Cardiovascular disease, hypertension and Type 2 Diabetes are major concerns worldwide and especially in black Africans. To note, South Africa and Russia currently has the highest hypertension prevalence rate in the world.
Proff A Alkerwi and L Malan met during the 2nd International Congress on “Prediabetes and the Metabolic syndrome”, Barcelona, Spain, April 2007. Mutual interest involved concerns on cardiometabolic morbidity and the rising metabolic syndrome epidemic. Therefore, they agreed to collaborate as both acted as Principal Investigators for epidemiological prospective studies, i.e. ORISLAV_LUX and SABPA studies.
Initial prospective findings from the SABPA study (http://stressed-project.co.za/data-dissemination/) demonstrated chronic defensive coping in the black and white South African cohort.  Despite more referrals to GPs, no change in risk for a hypertensive state or usage of hypertension drugs was revealed. However, increased prevalence was evident for central obesity (8.64 %) and Type 2 Diabetes (6.98 %). Findings underscore dissociation of defensive coping responses. Participants reported behavioral defensive “in-control” responses which were accompanied by physiological changes, indicative of possible “loss-of-control” responses. These findings emphasize the need to replicate findings in the Luxembourg population in the development of a diagnostic tool.
Ultimately, we propose a chain of causality of a brain-heart link (interaction between brain and cardio metabolic responses) as follows: taxing stress situations→ activates stress pathways → trigger neural, hemodynamic and metabolic functional changes → development of cardio metabolic disease.
There is thus a clear need for these collaborative prospective studies, including the impact of lifestyle changes, to additionally develop appropriate early prevention and intervention programs. We will also apply the new diagnostic tool via bioengineering modelling in expert groups to validate the tool for early preventive cardiology.