HMOX1 and amyotrophic lateral sclerosis: Interestingly, our data showed a statistically significant increase in mRNA expression levels of NFE2L2 (Figure 5A), HMOX1 (Figure 5B), and NQO1 (Figure 5C), which may well be a consequence of the observed increase in oxidative stress in this tissue induced by ALS-associated neurodegeneration [36,37].