Plasma FGF21 concentrations, adipose fibroblast growth factor receptor-1 and β-klotho expression decrease with fasting in northern elephant seals

Fibroblast growth factor (FGF)-21 is secreted from the liver, pancreas, and adipose in response to prolonged fasting/starvation to facilitate lipid and glucose metabolism. Northern elephant seals naturally fast for several months, maintaining a relatively elevated metabolic rate to satisfy their energetic requirements. Thus, to better understand the impact of prolonged food deprivation on FGF21-associated changes, we analyzed the expression of FGF21, FGF receptor-1 (FGFR1), β-klotho (KLB; a co-activator of FGFR) in adipose, and plasma FGF21, glucose and 3-hydroxybutyrate in fasted elephant seal pups. Expression of FGFR1 and KLB mRNA decreased 98% and 43%, respectively, with fasting duration. While the 80% decrease in mean adipose FGF21 mRNA expression with fasting did not reach statistical significance, it paralleled the 39% decrease in plasma FGF21 concentrations suggesting that FGF21 is suppressed with fasting in elephant seals. Data demonstrate an atypical response of FGF21 to prolonged fasting in a mammal suggesting that FGF21-mediated mechanisms have evolved differentially in elephant seals. Furthermore, the typical fasting-induced, FGF21-mediated actions such as the inhibition of lipolysis in adipose may not be required in elephant seals as part of a naturally adapted mechanism to support their unique metabolic demands during prolonged fasting

Microwave-assisted extraction of polysaccharides

In this chapter, the use of microwave irradiation has been reviewed and discussed for the extraction of polysaccharides as well as for combined processes involving extraction and hydrolysis of these compounds. Special attention has been paid to polysaccharides with bioactive properties. Fundamentals and instrumentation, together with a detailed discussion on the effect of the most important parameters affecting the microwave-assisted extraction (MAE) process, are presented. Some of the most recent and outstanding applications of MAE for the extraction of polysaccharides, mainly from food matrices or food by-products, are described and classified according to the type of polysaccharide extracted. The comparison in terms of speed, yield, etc. of MAE with other conventional (solid–liquid extraction) or emerging techniques (pressurized liquid extraction, ultrasound-assisted extraction) is also shown. The scale-up of MAE technique and the development of hybrid systems (e.g., ultrasonic–microwave-assisted extraction, UMAE) are shown as future trends. To conclude, MAE is shown as a promising emerging technique for extraction of polysaccharides from natural sources.This work has been funded by Ministerio de Economía y Competitividad (project CTQ2012-32957), Junta de Andalucía (project AGR-7626), and Comunidad de Madrid (project Avansecal). L. Ruiz-Aceituno is supported by a JAE-Predoc grant from CSIC and cofinanced by the European Social Fund (ESF). A.C.S. thanks Ministerio de Economía y Competitividad of Spain for a Ramón y Cajal contract.Peer reviewe

Microwave assisted extraction of polysaccharide

In this chapter, the use of microwave irradiation has been reviewed and dicussed for the extraction of polysaccharides as well as for combined processes involving extraction and hydrolysis of these compounds. Special attention has been paid to polysaccharides with bioactive properties. Fundamentals and instrumentation, together with a detailed discussion on the effect of the most important parameters affecting the microwave-assisted extraction (MAE) process are presented. Some of the most recent and outstanding applications of MAE for the extraction of polysaccharides, mainly from food matrices or food byproducts, are described and classified according to the type of polysaccharide extracted. The comparison in terms of speed, yield, etc. of MAE with other conventional (solid-liquid extraction) or emerging techniques (pressurized liquid extraction, ultrasound-assisted extraction) is also shown. The scale-up of MAE technique and the development of hybrid systems (e.g. ultrasound-microwave-assisted extraction, UMAE) are presented as future trends. To conclude, MAE is presented as a promising emerging technique for extraction of polysaccharides from natural sources.Peer reviewe

Sequence variants in SLC16A11 are a common risk factor for type 2 diabetes in Mexico

10.1038/nature12828Nature506748697-101NATU

Sequence variants in SLC16A11 are a common risk factor for type 2 diabetes in Mexico

Performing genetic studies in multiple human populations can identify disease risk alleles that are common in one population but rare in others, with the potential to illuminate pathophysiology, health disparities, and the population genetic origins of disease alleles. Here we analysed 9.2 million single nucleotide polymorphisms (SNPs) in each of 8,214 Mexicans and other Latin Americans: 3,848 with type 2 diabetes and 4,366 non-diabetic controls. In addition to replicating previous findings, we identified a novel locus associated with type 2 diabetes at genome-wide significance spanning the solute carriers SLC16A11 and SLC16A13 (P = 3.9 × 10(-13); odds ratio (OR) = 1.29). The association was stronger in younger, leaner people with type 2 diabetes, and replicated in independent samples (P = 1.1 × 10(-4); OR = 1.20). The risk haplotype carries four amino acid substitutions, all in SLC16A11; it is present at ~50% frequency in Native American samples and ~10% in east Asian, but is rare in European and African samples. Analysis of an archaic genome sequence indicated that the risk haplotype introgressed into modern humans via admixture with Neanderthals. The SLC16A11 messenger RNA is expressed in liver, and V5-tagged SLC16A11 protein localizes to the endoplasmic reticulum. Expression of SLC16A11 in heterologous cells alters lipid metabolism, most notably causing an increase in intracellular triacylglycerol levels. Despite type 2 diabetes having been well studied by genome-wide association studies in other populations, analysis in Mexican and Latin American individuals identified SLC16A11 as a novel candidate gene for type 2 diabetes with a possible role in triacylglycerol metabolism