Stenocereus huastecorum-fruit juice concentrate protects against cisplatin-induced nephrotoxicity by nitric oxide pathway activity and antioxidant and antiapoptotic effects.

Cisplatin (CP) is an antineoplastic agent used to treat solid tumors, that has high nephrotoxicity caused by physiologic, hemodynamic, and biochemical alterations. Some studies have shown that naturally derived bioactive compounds in CP-induced nephrotoxicity reduce the side effects of this antineoplastic drug. Pitaya is an endemic fruit from Mexico with a high bioactive compound content, including betalains and phenolic compounds, with reports of antioxidant and anti-inflammatory properties. In this study, the aim was to establish the effect of a pitaya juice concentrate (PJC) on CP-induced nephrotoxicity in Wistar male rats through the identification of metabolites, determination of its chemical composition and antioxidant activity, and evaluation of the protective effect of a PJC on CP-induced nephrotoxicity in rats. The PJC showed a high content of betanins with antioxidant activity by an oxygen radical absorbance capacity assay (1299.6 ± 2.80 Trolox equivalents/g). PJC was administered daily (400 mg day-1, p. o.) for 3 days before CP administration until the end of the experiment. On day four, rats were administered a single injection of CP (6 mg kg, i.p.-1) and sacrificed 72 h later. We observed that CP provoked renal dysfunction (1.0 ± 0.1 vs. 0.4 ± 0.07 serum creatinine levels), oxidative stress, a decrease in nitrate and nitrite (NO2¯/NO3¯) levels (0.1 ± 0.08 vs. 0.4 ± 0.3) and activation of apoptosis and immune responses in kidney tissue. In addition, CP treatment induced tubular damage threefold. PJC administration prevented renal dysfunction (0.5 ± 0.06 vs. 1.0 ± 0.1), normalized degenerative structural damage prevented the increase in lipoperoxidation levels (0.04 ± 0.01 vs. 0.2 ± 0.1) and reduced the apoptosis index by 2.5 in kidney tissue. However, it did not modify the immune response caused by CP. Furthermore, PJC treatment increased nuclear factor erythroid two related factors two protein levels two times and NO2¯/NO3¯ levels 22 times in kidney tissue, which may play a role in the renoprotective effect. In conclusion, the renoprotective effect of PJC on CP-induced nephrotoxicity was associated with the attenuation of dysfunction, structural damage, apoptosis activation, and oxidative stress and was related to changes in the tumor necrosis factor-alpha and renal nitric oxide (NO) pathways. The changes in the NO pathway may be involved in renal hemodynamics. Pitaya could be used as a functional food and therapeutic coadjuvant during CP treatments due to its high bioactive levels and renoprotective compounds.

Research opportunities: Traditional fermented beverages in Mexico. Cultural, microbiological, chemical, and functional aspects.

In Mexico, close to 200 fermented products have been described, of which, approximately 20 are beverages. They were obtained through rustic and ancestral fermentation methods by different indigenous Mexican communities; most of them were used in ceremonies, agricultural work, and other occasions. For their elaboration, different substrates obtained from plants are used, where uncontrolled and low-scale spontaneous anaerobic fermentation occurs. In Mexico, some of these products are considered as nutritional sources and functional beverages; the study of those products has revealed the presence of multiple compounds of biological importance. Additionally, elder generations attribute healing properties against diverse illnesses to these beverages. The aim of this review is to highlight the available information on twelve traditional Mexican fermented beverages, their traditional uses, and their fermentation processes along with toxicological, chemical, nutritional, and functional studies as seen from different areas of investigation. In the literature, pulque, cocoa, and pozol were the beverages with the greatest amount of described health properties; sendechó and guarapo were less characterized. Polyphenols, gallic and ferulic acid, anthocyanins and saponins were the most abundant molecules in all beverages. Finally, it is important to continue this research in order to determine the microorganisms that are involved in the fermentation process, as well as the organoleptic and beneficial properties they lend to the traditional Mexican fermented beverages.