Adulterated dietary supplements commercialized in Brazil: development of a screening method and a preliminary study of cytotoxicity.

The high consumption of dietary supplements was a fundamental driver for the creation of the regulatory framework by the Brazilian governmental authorities. However, the regulatory agencies lack official low-cost methodologies to evaluate the quality of food supplements. A preliminary screening method by HPLC-DAD was proposed and validated for screening and quantification of adulterants in dietary supplements. The limits of detection and quantification were <0.11 and 0.37 µg.g-1, respectively. The method was applied for the investigation of ten unauthorized substances (spironolactone, hydrochlorothiazide, furosemide, clenbuterol, testosterone, testosterone propionate, yohimbine, vardenafil, tadalafil, and sildenafil) with a time of analysis of <5 min. Sixteen percent of the 44 samples analyzed had at least one adulterant at or above therapeutic concentrations. Subsequently, in vitro evaluations were performed of the potential cytotoxicity to evaluate the cell viability, DNA damage, determination of nitric oxide levels, and quantification of reactive oxygen species. Despite the necessity of further studies, the results indicate a relationship between the presence of adulterants in food supplements and a potential cytotoxic effect.

Pomegranate seed oil nanoemulsions with selective antiglioma activity: optimization and evaluation of cytotoxicity, genotoxicity and oxidative effects on mononuclear cells.

CONTEXT: Glioma is a malignant brain tumor with rapid proliferation, infiltrative growth, poor prognosis and it is chemoresistent. Pomegranate seed oil (PSO) has antioxidant, anti-inflammatory and antitumor properties. This study showed the optimization of PSO nanoemulsions (NEs) as an alternative for glioma treatment. OBJECTIVE: The study aimed to evaluate PSO NEs cytotoxicity on human blood cells and antiglioma effects against C6 cells. MATERIALS AND METHODS: NEs were prepared by the spontaneous emulsification method, using PSO at 1.5 and 3.0%, and were evaluated regarding their physical stability and antioxidant activity. Toxicity evaluations in human blood cells were performed in terms of cell viability, genotoxicity, lipid peroxidation, protein carbonylation, catalase activity and hemolysis at 0.1, 0.25 and 0.5 mg/mL PSO, after a 72-h incubation period. In vitro antitumor effect was determined against glioma cells after 24 and 48 h, and astrocytes were used as a non-transformed cell model. RESULTS: Formulations presented droplet size below 250 nm, low polydispersity index, negative zeta potential and pH in the acid range. NEs and PSO had scavenging capacity around 30% and promoted a proliferative effect in mononuclear cells, increasing about 50% cell viability. No genotoxic and oxidative damage was observed in lipid peroxidation, protein carbonylation and catalase activity evaluations for NEs. Hemolysis study showed a hemolytic effect at high concentrations. Moreover, formulations reduced only tumor cell viability to 47%, approximately. DISCUSSION AND CONCLUSION: Formulations are adequate and safe for intravenous administration. Besides, in vitro antitumor activity indicates that NEs are promising for glioma treatment.