Jatropha curcas Protein Concentrate Stimulates Insulin Signaling, Lipogenesis, Protein Synthesis and the PKCα Pathway in Rat Liver.

Jatropha curcas is an oil seed plant that belongs to the Euphorbiaceae family. Nontoxic genotypes have been reported in Mexico. The purpose of the present work was to evaluate the effect of a Mexican variety of J. curcas protein concentrate (JCP) on weight gain, biochemical parameters, and the expression of genes and proteins involved in insulin signaling, lipogenesis, cholesterol and protein synthesis in rats. The results demonstrated that short-term consumption of JCP increased serum glucose, insulin, triglycerides and cholesterol levels as well as the expression of transcription factors involved in lipogenesis and cholesterol synthesis (SREBP-1 and LXRα). Moreover, there was an increase in insulin signaling mediated by Akt phosphorylation and mTOR. JCP also increased PKCα protein abundance and the activation of downstream signaling pathway targets such as the AP1 and NF-κB transcription factors typically activated by phorbol esters. These results suggested that phorbol esters are present in JCP, and that they could be involved in the activation of PKC which may be responsible for the high insulin secretion and consequently the activation of insulin-dependent pathways. Our data suggest that this Mexican Jatropha variety contains toxic compounds that produce negative metabolic effects which require caution when using in the applications of Jatropha-based products in medicine and nutrition.

Anti-Helicobacter pylori Potential of Three Edible Plants Known as Quelites in Mexico.

"Quelites" are edible plants that are part of the traditional agro-ecosystems in Mexico. These plants, despite their already known nutritional properties, are now considered neglected and underutilized species. With the objective of promoting their reinsertion in the markets and mainly, in daily diets, efforts have been made to study them from multidisciplinary approaches to demonstrate their beneficial properties. To generate evidence of an added health-promoting value that would encourage quelites consumption, in the present work, the anti-Helicobacter pylori activity of three representative quelite species, Anoda cristata (Alache), Cnidoscolus aconitifolius (Chaya), and Crotalaria pumila (Chepil), was tested. H. pylori is considered the etiological agent of gastritis, ulcer, and gastric cancer, and represents a public health problem in Mexico and worldwide. Aqueous (AQ) and dichloromethane-methanol (DM) extracts were obtained from the three species of quelites to investigate their effect on H. pylori growth and on two of its colonization factors (adherence and urease activity). DM extracts from Chaya, Chepil, and Alache exert the best inhibitory effect on bacterial growth, with minimum inhibitory concentrations of 62.5, 125, and 250 µg/mL, respectively. AQ and DM extracts inhibit bacterial adhesion by 30% to 50%. None of them has an effect on urease activity. The two flavonoids present in A. cristata, acacetin and diosmetin, inhibit H. pylori growth by ∼90% with 3.9 µg/mL. These results provide new information about the anti-H. pylori potential of three edible quelites, and give an added value, since their routine consumption may impact on the prevention and/or control of H. pylori-associated diseases.

The hexokinase gene family in the zebrafish: structure, expression, functional and phylogenetic analysis.

Hexokinase-catalyzed glucose phosphorylation is the first and crucial step for glucose utilization. Although there are reported studies on glucose metabolism in commercial species, knowledge on it is almost nil in zebrafish (Danio rerio), an important model organism for biological research. We have searched these fish hexokinase genes by BLAST analysis; determined their expression in liver, muscle, brain and heart; measured their response to fasting and glucose administration; and performed homology sequences studies to glimpse their evolutionary history. We have confirmed by RT-qPCR studies that the six DNA sequences annotated as possible hexokinases in the NCBI GenBank are transcribed. The organ distribution of the HXK genes is similar in zebrafish as in mammals, to which they are distantly related. Of these, DrGLK and DrSHXK1 are expressed in the fish liver, DrHXK1 in brain and heart, and DrHXK2 in muscle. The only gene responsive to glucose was liver DrGLK. Its expression is induced approximately 1 h after glucose intraperitoneal injection, but not after saline solution injection. The comparison of the fish sequences and the corresponding mammalian ones imply that in both taxa the main muscle and brain isoforms are fusion products of the ancestral gene, their amino halves having separated before than their carboxy ones, followed by the fusion event, whereas fish and mammalian glucokinase genes remained unduplicated.

Preparation of fish protein isolate and hydrolyzate (Mugil cephalus) and their incorporation into Mexican foods

Fish protein isolates (FPI) and hydrolyzates (FPH) were obtained from mullet (Mugil cephalus) through alkali solubilization and HCI precipitation for FPI, as well as enzymatic hydrolysis for FPH. The powdered products showed solubilities of 50 and 89%, and emulsifying capacities of 36 and 39 ml oil/100 mg for FPI and FPH, respectively, with protein contents of 90% and oil contents lower than 1.6%. Both products were used to enrich cereals and legumes in order to increase their protein content and quality. The resulting mixtures were used to prepare common Mexican dishes. When up to 20 and 35% of the total protein was provided by FPI and FPH, respectively, the dishes were well acepted by 70% of the panel