Dr Luiza Steffens Reinhardt

Mucopolysaccharidosis type II (MPS II or Hunter Syndrome) is a lysosomal disease caused by deficient degradation of glycosaminoglycans (GAGs) heparan sulfate and dermatan sulfate due to the deficiency of the enzyme iduronate-2-sulfatase. The main treatment for MPS II is the administration of the recombinant form of the enzyme, in a process known as enzyme replacement therapy (ERT). Oxidative damage can contribute to the pathophysiology of MPS II and treatment with ERT can reduce the effects of oxidative stress. For a better understanding of pathophysiology of MPS II, we evaluated biomarkers of mitochondrial dysfunction, DNA (Deoxyribonucleic acid) damage, antioxidant defenses, reactive species production and lysosomal size in IDS-deficient HEK 293 cells and investigate the in vitro effect of genistein and coenzyme Q10 (CoQ) on these biomarkers. An increase in the production of reactive species was demonstrated, as well as an increase in the activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). Also, an increase in lysosomal volume and oxidative damage to DNA were verified. There was no evidence of a change in mitochondrial function in this cell model. In the HEK 293 (human embryonic kidney 293) knockout (KO) HP10 cell model we found that genistein at concentrations of 25 and 50¿µm decreased in vitro the production of reactive species and the activity of the SOD enzyme, showing an antioxidant protective effect. Still, in these cells we verified that the coenzyme Q10 in the concentrations of 5 and 10¿µm decreased in vitro the activity of the SOD enzyme and in the concentration of 10¿µm decreased in vitro the DNA damage, also demonstrating antioxidant protection. In conclusion, MPS II knockout cells demonstrated oxidative stress and DNA damage and genistein, as well as coenzyme Q10, have been shown to have an important protective effect in vitro against these oxidative damages.

Niemann Pick type C is an inborn error of metabolism (IEM), classified as a lysosomal storage disease (LSD) caused by a dysfunction in NPC transport protein, that leads to intracellular accumulation of non-esterified cholesterol and other lipids. Clinical manifestations are ample, with visceral and neurological symptoms. Miglustat, a molecule that reversibly inhibits glucosylceramide synthase is used as treatment for this disorder. Studies demonstrated the influence of oxidative stress and inflammation in IEM, as well in animal model of NP-C disease. Nonetheless, literature lacks data on patients, so our work aimed to investigate if there is influence of chronic inflammation in the pathophysiology of NP-C disease, and the effect of miglustat, N-acetylcysteine (NAC) and Coenzyme Q10 (CoQ10). We evaluated the plasmatic cytokines in NPC patients at diagnosis and during the treatment with miglustat. Additionally, we performed an in vitro study with antioxidants NAC (1 mM and 2.5 mM) and CoQ10 (5 µM and 10 µM), where we could verify its effect on inflammatory parameters, as well as in cholesterol accumulation. Our results showed that NP-C patients have higher plasmatic levels of pro and anti-inflammatory cytokines (IL-6, IL-8, and IL-10) at diagnosis and the treatment with miglustat was able to restore it. In vitro study showed that treatment with antioxidants in higher concentrations significantly decrease cholesterol accumulation, and NAC at 2.5 mM normalized the level of pro-inflammatory cytokines. Although the mechanism is not completely clear, it can be related to restoration in lipid traffic and decrease in oxidative stress caused by antioxidants.

Maternal diet is key to the progeny¿s health since it may impact on the offspring¿s adult life. In this study, mice dams received standard (CONT), restrictive (RD), or hypercaloric (HD) diets during mating, pregnancy, and lactation. Male offspring of each group of dams also received these diets: CONT, RD, HD. Aiming to evaluate the oxidative stress in the adipose tissue, reactive oxygen species (ROS) production, catalase (CAT), and superoxide dismutase (SOD) activities were analyzed in dams and offspring. In the adipose tissue and hypothalamus, gene expression of prolactin (Prlr) and estrogen alpha (Esr1) receptors was performed in dams and offspring. Protein expression of Stat5 was evaluated in the adipose tissue of the offspring from RD-fed dams. HD-fed dams increased triglycerides and leptin serum concentrations, and decreased SOD activity in the adipose tissue. In the offspring¿s adipose tissue, we observed a maternal diet effect caused by HD, with increased ROS production and SOD and CAT activities. Gene expression of Prlr and Esr1 in the offspring¿s adipose tissue was decreased due to maternal RD. Mice from HD-fed dams showed higher Stat5 expression compared to the offspring from CONT and RD dams in the adipose tissue. In the hypothalamus, we found decreased expression of Prlr in RD and HD dams, compared to CONT; and a maternal diet effect on Prlr and Esr1 gene expression in the offspring. In conclusion, we can affirm that maternal nutrition impacts the redox state and influences the gene expression of Prlr and Esr1, which are involved in energy metabolism, both peripherally and centrally in the adult life of the female offspring.