Extracellular matrix (ECM) remodeling and oxidative stress is present in hypertension and associated arterial stiffness, but little is known on the physiological link between a marker of tissue damage (lactate dehydrogenase (LDH)), ECM glycoprotein fibulin-1 and reactive oxygen species (ROS). We explored the link between LDH, fibulin-1 (as ECM biomarker) and ROS as a measure of oxidative stress.Design and Method:
We included 316 black and 305 white South Africans from a cross-sectional population study and determined the abovementioned biomarkers along with additional cardiovascular and metabolic risk factors.Results:
LDH levels were lower in black compared to white participants (p < 0.001), but fibulin-1 along with ROS and blood pressure levels were higher in black participants (p < 0.001). Gamma-glutamyl transferase mean was higher in black than in white participants (p < 0.001). LDH associated positively with fibulin-1 (β = 0.23; p < 0.001) and ROS (β = 0.11; p = 0.30) in black participants only. We performed a multiple regression analysis and confirmed the significant positive relationship of LDH with fibulin-1 (β = 0.23; p < 0.001) previously observed in black participants only. However, significance was lost between LDH and ROS due to the interaction of HIV infection.Conclusions:
Our finding suggests that increased circulating levels of LDH may be due to early subclinical ECM remodelling and oxidative stress in black individuals that are subjected to detrimental and uncontrolled lifestyle risk factors. Our result between tissue damage and oxidative stress is also strengthened by the link we observed between LDH and a marker of alcohol abuse in the black population. Further analysis is warranted to elucidate the absence of this association in HIV infection.