Marco A. Gallegos-Corona

Antioxidant, anti-inflammatory and anticarcinogenic activities of edible red oak (Quercus spp.) infusions in rat colon carcinogenesis induced by 1,2-dimethylhydrazine

Red oak (Quercus spp.) leaves are traditionally used as food in Mexico, and some of their infusions have potential anticarcinogenic and anti-inflammatory effects; however, these properties have not yet been scientifically tested. The aim of this work was to explore the anti-inflammatory activity in HT-29 cells and anticarcinogenic effect in 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis of red oak infusions. Quercus infusions were prepared and administered as the sole source of drink to male Sprague-Dawley rats (1% w/v) for the entire 26-week experimental period. On week 4, rats received 8 subcutaneous injections of DMH (21 mg/kg body weight) once a week. The results showed that mean tumor (0.9 ± 0.2 vs. 2.6 ± 0.3) and multiplicity (1.2 ± 0.1 vs. 2.0 ± 0.23), and β-catenin protein level (2.2-fold) in adenocarcinomas were significantly lower in Quercus  sideroxyla-treated group compared with DMH group. By contrast, Quercus  durifolia and Quercus  eduardii infusions had no protective effect. Additionally, the experiments in HT-29 cells confirmed that Q. sideroxyla infusion effectively decreased the levels of the inflammatory markers COX-2 and IL-8 by modulating the expression of NF-κB. These results highlight some of the molecular mechanisms related to the chemopreventive effect of Q. sideroxyla infusion and its potential value as a source of bioactive compounds.

Protective effects of dietary avocado oil on impaired electron transport chain function and exacerbated oxidative stress in liver mitochondria from diabetic rats.

Electron transport chain (ETC) dysfunction, excessive ROS generation and lipid peroxidation are hallmarks of mitochondrial injury in the diabetic liver, with these alterations also playing a role in the development of non-alcoholic fatty liver disease (NAFLD). Enhanced mitochondrial sensitivity to lipid peroxidation during diabetes has been also associated to augmented content of C22:6 in membrane phospholipids. Thus, we aimed to test whether avocado oil, a rich source of C18:1 and antioxidants, attenuates the deleterious effects of diabetes on oxidative status of liver mitochondria by decreasing unsaturation of acyl chains of membrane lipids and/or by improving ETC functionality and decreasing ROS generation. Streptozocin-induced diabetes elicited a noticeable increase in the content of C22:6, leading to augmented mitochondrial peroxidizability index and higher levels of lipid peroxidation. Mitochondrial respiration and complex I activity were impaired in diabetic rats with a concomitant increase in ROS generation using a complex I substrate. This was associated to a more oxidized state of glutathione, All these alterations were prevented by avocado oil except by the changes in mitochondrial fatty acid composition. Avocado oil did not prevented hyperglycemia and polyphagia although did normalized hyperlipidemia. Neither diabetes nor avocado oil induced steatosis. These results suggest that avocado oil improves mitochondrial ETC function by attenuating the deleterious effects of oxidative stress in the liver of diabetic rats independently of a hypoglycemic effect or by modifying the fatty acid composition of mitochondrial membranes. These findings might have also significant implications in the progression of NAFLD in experimental models of steatosis.

Gastroprotective potential of Buddleja scordioides Kunth Scrophulariaceae infusions; effects into the modulation of antioxidant enzymes and inflammation markers in an in vivo model.

ETHNOPHARMACOLOGICAL RELEVANCE A common plant used to treat several gastric disorders is Buddleja scordioides Kunth, commonly known as salvilla. AIM OF THE STUDY To detect inflammatory markers, in order to evaluate the gastroprotective potential of salvilla infusions, as this could have beneficial impact on the population exposed to gastric ulcers and colitis. MATERIALS AND METHODS The present work attempted infusions were prepared with B. scordioides (1% w/w) lyophilized and stored. Total phenolic content and GC-MS analysis were performed. Wistar rats were divided into five groups (n=8), a negative vehicle control, an indomethacin group, and three experimental groups, named preventive, curative, and suppressive. All rats were sacrificed under deep ether anesthesia (6h) after the last oral administration of indomethacin/infusion. The rat stomachs were promptly excised, weighed, and chilled in ice-cold and 0.9% NaCl. Histological analysis, nitrites quantification and immunodetection assays were done. RESULTS B. scordioides infusions markedly reduced the visible hemorrhagic lesions induced by indomethacin in rat stomachs, also showed down-regulation of COX2, IL-8 and TNFα and up-regulation of COX-1 with a moderate down-regulation of NFkB and lower amount of nitrites. However, this behavior was dependent on the treatment, showing most down-regulation of COX-2, TNFα and IL-8 in the curative treatment; more down-regulation of NF-kB in the preventive treatment; and more up-regulation of COX-1 for the suppressor and preventive treatments. CONCLUSION The anti-inflammatory potential of B. scordioides infusions could be related with the presence of polyphenols as quercetin in the infusion and how this one is consumed.

Transcriptomic Analysis in Diabetic Nephropathy of Streptozotocin-Induced Diabetic Rats

Diabetic nephropathy (DN) is a major complication of diabetes and is caused by an imbalance in the expression of certain genes that activate or inhibit vital cellular functions of kidney. Despite several recent advances, the pathogenesis of DN remains far from clear, suggesting the need to carry out studies identifying molecular aspects, such as gene expression, that could play a key role in the development of DN. There are several techniques to analyze transcriptome in living organisms. In this study, the suppression subtractive hybridization (SSH) method was used to generate up- and down-regulated subtracted cDNA libraries in the kidney of streptozotocin (STZ)-induced diabetic rats. Northern-blot analysis was used to confirm differential expression ratios from the obtained SSH clones to identify genes related to DN. 400 unique SSH clones were randomly chosen from the two subtraction libraries (200 of each) and verified as differentially expressed. According to blast screening and functional annotation, 20.2% and 20.9% of genes were related to metabolism proteins, 9% and 3.6% to transporters and channels, 16% and 6.3% to transcription factors, 19% and 17.2% to hypothetical proteins, and finally 24.1 and 17.2% to unknown genes, from the down- and up-regulated libraries, respectively. The down- and up-regulated cDNA libraries differentially expressed in the kidney of STZ diabetic rats have been successfully constructed and some identified genes could be highly important in DN.

Tolerability assessment of a lectin fraction from Tepary bean seeds (Phaseolus acutifolius) orally administered to rats

Highlights • We examine the toxicological profile of Tepary Bean lectins by oral route.• Tepary bean lectins showed digestion resistance up to 72 h.• Tepary bean lectins induce granulocyte increase after 24 h treatment.• A reduction in body weight gain was observed after 6 weeks treatment.• No toxicity was observed for Tepary bean lectins after 6 weeks.

Long-term toxicological effects of persistent luminescence nanoparticles after intravenous injection in mice

The ZnGa1.995Cr0.005O4 persistent luminescence nanoparticles offer the promise of revolutionary tools for biological imaging with applications such as cell tracking or tumor detection. They can be re-excited through living tissues by visible photons, allowing observations without any time constraints and avoiding the undesirable auto-fluorescence signals observed when fluorescent probes are used. Despite all these advantages, their uses demand extensive toxicological evaluation and control. With this purpose, mice were injected with a single intravenous administration of hydroxylated or PEGylated persistent luminescence nanoparticles at different concentrations and then a set of standard tests were carried out 1day, 1 month and 6 months after the administration. High concentrations of hydroxylated nanoparticles generate structural alterations at histology level, endoplasmic reticulum damage and oxidative stress in liver, as well as rising in white blood cells counts. A mechanism involving the endoplasmic reticulum damage could be the responsible of the observed injuries in case of ZGO-OH. On the contrary, no toxicological effects related to PEGylated nanoprobes treatment were noted during our in vivo experiments, denoting the protective effect of PEG-functionalization and thereby, their potential as biocompatible in vivo diagnostic probes.