The prevalence of hypertension is significantly higher in African Americans in comparison to other populations. Hypertension is a condition in which there is increased blood pressure in the arterial walls, which can lead to serious health problems such as heart attack and stroke. The African American population has been shown to have a higher risk of developing kidney failure than Caucasians due to hypertension. Apolipoprotein (ApoL) encodes the apolipoprotein L-1 protein (ApoL1) and has been shown to be prevalent in the African American population. Apocynin is a known inhibitor of NADPH oxidase (NOX), which catalyzes the reduction of molecular oxygen to the superoxide and has been shown to prevent the formation of reactive oxygen species, which decreases arterial stiffness in deoxycorticosterone acetate-salt-induced hypertensive (DSH) rats. A reduction in the amount of reaction oxygen species leads to a decrease in apoptosis. We hypothesize that because apocynin causes a reduction in reactive oxygen species, then it will cause inhibition of the PI3K/Akt pathway. In order to test this hypothesis, twenty-four male DSH rats were treated with a low salt diet (0.3% sodium chloride) with apocynin and aldosterone or a high salt diet (8% sodium chloride). The kidneys of the rats were homogenized and tested for the presence of APOL-1 using ELISA and Western Blot. The expression of NOX4 (an NADPH oxidase subuint) was also tested using ELISA.The rats that were fed a low salt diet exhibited the APOL-1 protein. In the presence of high salt or aldosterone, ApoL1 expression was completely inhibited. The expression of NOX4 was also seen in all of the rats (n = 24), but was higher in the rats fed a low salt diet (n = 12). Apocynin did not affect NOX4 expression, but did increase the production of reactive oxygen species. ApoL-1, along with apocynin, have an effect on Akt-signaling. However, instead of reducing the amount of reactive oxygen species, apocynin appears to be inhibited in the presence of the ApoL-1 protein and upregulates the Akt pathway. Future tests will involve identifying receptors in the Akt pathway that are affected by apocynin, which could lead to conclusions about the effect of apocynin and oxidative stress on the kidney.
"The Effect of Apocyin on the APOL-1 Gene in the African American Population,"
Continuum: The Spelman Undergraduate Research Journal: Vol. 1
, Article 4.
Available at: http://digitalcommons.auctr.edu/continuum/vol1/iss1/4