Narrow-leafed lupin (Lupinus angustifolius L.) seed ß-conglutins reverse the induced insulin resistance in pancreatic cells.

Insulin resistance (IR) is the main contributor to the development of type 2 diabetes. In this study, we have purified recombinant ß-conglutin proteins (rß1 to rß4, and rß6) from narrow-leafed lupin (NLL) by using affinity chromatography. The objective of this study was to evaluate the capacity of these ß-conglutins to improve the IR state using ex vivo and in vitro systems. rß1, rß3, and rß6 produced lower levels of pro-inflammatory mediator nitric oxide (about -7-fold in all cases), up-regulated mRNA expression levels of IRS-1 (+201, +173, +192%) and Glut-4 (+286, +121, +147%), increased levels of p85-PI3K (+188, +187, +137-fold) and Glut-4 (+503, +548, +515-fold) proteins, higher phosphorylation levels of the insulin signalling pathway activator p-IRS-1 and downstream mediators such as p-Akt, p-Cbl, and p-caveolin, and improved glucose uptake in insulin resistant (IR-C) culture cells. ß-conglutin proteins were able to suppress the oxidative stress produced by insulin-induced resistance on PANC-1 control (C) cells by strongly reducing the protein oxidative carbonylation induced by ROS and balancing the metabolic homeostasis in IR-C cells through regulation of mRNA expression. At the same time, ß-conglutins are able to reduce the levels of the pro-inflammatory mediator nitric oxide and promote the anti-oxidative capacity of cells by increasing the levels of reduced glutathione. These results suggest NLL ß-conglutins might play a fundamental role as functional food components, since ß-conglutins' nutraceutical properties could enhance the effectiveness of dietary improvement of type 2 diabetes complications.

Narrow-leafed lupin (Lupinus angustifolius L.) ß-conglutin proteins modulate the insulin signaling pathway as potential type 2 diabetes treatment and inflammatory-related disease amelioration.

SCOPE: We have investigated the potential use of ß-conglutin protein isoforms from narrow-leafed lupin (Lupinus angustifolius L.) as a diabetes treatment. METHODS AND RESULTS: We produced purified recombinant ß1-, ß2-, ß3-, ß4-, and ß6-conglutin proteins and showed that ß1, ß3, and ß6 could bind to insulin. To assess ß-conglutin proteins modulatory effect on insulin activation meditated kinases, whole blood and peripheral blood mononuclear cell cultures from type 2 diabetes (T2D) and healthy control subjects (C) were incubated with conglutin proteins. The treatment of peripheral blood mononuclear cells from T2D patients with ß1, ß3, and ß6 proteins increased up to threefold mRNA and protein levels of genes important in insulin signaling pathways, namely insulin receptor substrate 1/p85/AKT/glucose transporter type 4. This was accompanied by a comparable fold-change decrease in the mRNA expression level of pro-inflammatory genes (iNOS and IL-1ß) and proteins compared to healthy controls. The ß2 and ß4 isoforms had no effect on the insulin signaling pathway. However, these ß-conglutin proteins elicited pro-inflammatory effects since levels of mRNA and proteins of inducible nitric oxide synthase and IL 1 beta were increased. CONCLUSION: Our results raise the possibility of using these particular ß-conglutin proteins in the prevention and treatment of diabetes, as well as their potential as anti-inflammatory molecules.

Pollen from different olive tree cultivars contains varying amounts of the major allergen Ole e 1.

BACKGROUND: Commercial olive pollen from uncertain cultivar origin is the common material used for clinical and biological studies. We aimed to assess the putative heterogeneity of olive cultivars with regard to the presence of the major pollen allergen Ole e 1 and to determine whether these differences have clinical relevance. METHODS: The Ole e 1 content of several cultivars was determined by immunoblotting and ultrastructural immunocytochemistry and compared to that of a commercially available olive pollen extract designed for diagnosis. Reverse transcription-polymerase chain reaction analysis of Ole e 1 transcripts was also performed. Crude protein extracts were used to carry out skin prick tests (SPTs) on 30 allergic patients in order to evaluate the clinical importance of such differences. RESULTS: Ole e 1 was present in all cultivars, although significant quantitative differences were detected. Ole e 1 transcripts positively correlated with the amount of the allergen. Significant variations in the average reactivity of allergic patients to SPTs were observed depending on the cultivar considered. CONCLUSIONS: The presence of the Ole e 1 allergen in all the cultivars suggests that this allergen may play an essential biological role. The expression of the allergen is controlled at the transcriptional level. The significant differences in the Ole e 1 content are likely responsible for the different average reactivity exhibited by patients to the cultivars studied, although the role of other allergens cannot be excluded. Our results suggest that the use of the commercial pollen mixtures currently available may lead to mistakes in allergy diagnosis and to limited success in immunotherapy. Therefore, further standardization is strongly recommended.