Síndrome de Quilomicronemia Familiar: Algoritmo Diagnóstico

A hipertrigliceridemia, a par do aumento do risco cardiovascular pode, em níveis muito elevados, ter consequências como a pancreatite recorrente e dor abdominal. A síndrome da quilomicronemia familiar (SQF) é uma doença autossómica recessiva rara do metabolismo dos quilomicra, causada mais frequentemente por mutação do gene da lipoproteína lipase. A concentração plasmática de triglicéridos (TG) pode ser dez vezes superior ao normal. Distinguir esta condição da quilomicronemia multifactorial (QMM) pode tornar-se difícil pela semelhança fenotípica, sendo necessário realizar o teste genético. O tratamento da hipertrigliceridemia foca-se na prevenção da pancreatite em doentes com hipertrigliceridemia grave e na redução do risco cardiovascular global. O volanesorseno é um fármaco indicado na SQF que actua sobretudo pela clearance dos TG por vias independentes da LPL, atingindo em estudos de fase 2 reduções da apoC-III e de TG de 79,6% e 70,9% respectivamente; em estudos de fase 3, a redução de TG foi de 77%, com efeitos adversos minor. Os dados acerca da redução de risco cardiovascular são mais limitados. Tendo em conta a realidade nacional, os autores propõem um algoritmo de abordagem da hipertrigliceridemia que se inicia nos Cuidados de Saúde Primários com a exclusão de causas secundárias de hipertrigliceridemia e determinação da necessidade de referenciação a uma consulta de especialidade para confirmação do diagnóstico, com base no score do SQF sugerido por Moulin et al em 2018.

Deficiency in endocannabinoid synthase DAGLB contributes to Parkinson's disease and dopaminergic neuron dysfunction

2-arachidonoyl-glycerol (2-AG), the most abundant endocannabinoid (eCB) in the brain, regulates diverse neural functions. However, whether 2-AG deficiency contributes to Parkinson's disease (PD) and nigral dopaminergic neurons (DANs) dysfunction is unclear. Diacylglycerol lipase A and B (DAGLA and DAGLB) mediate the biosynthesis of 2-AG. Using homozygosity mapping and whole-exome sequencing, we linked multiple homozygous loss-of-function mutations in DAGLB to a form of early-onset autosomal recessive PD. We then used RNA sequencing and fiber photometry with genetically encoded eCB sensors to demonstrate that DAGLB is the main 2-AG synthase in nigral DANs. Genetic knockdown of Daglb by CRISPR/Cas9 in mouse nigral DANs substantially reduces 2-AG levels in the substantia nigra (SN). The SN 2-AG levels are markedly correlated with the vigor of movement during the acquisition of motor skills, while Daglb-deficiency impairs motor learning. Conversely, pharmacological enhancement of 2-AG levels increases nigral DAN activity and dopamine release and improves motor learning. Together, we demonstrate that DAGLB-deficiency contributes to the etiopathogenesis of PD, reveal the importance of DAGLB-mediated 2-AG biosynthesis in nigral DANs in regulating neural activity and dopamine release, and provide preclinical evidence for the beneficial effects of 2-AG augmentation in PD treatment.

Avaliação da hidrólise da lactose por β-galactosidase comercial em leite UHT

O leite é um alimento consumido amplamente por pessoas de todas as faixas etárias, em razão de fornecer cálcio e proteína para a dieta humana. Com o aumento do número de pessoas com deficiência da enzima lactase, que ocasiona distúrbios gastrointestinais após o consumo de leite e seus derivados, diversas são as inovações que facilitam a alimentação das pessoas que possuem intolerância. De tal maneira, a enzima lactase de origem microbiana tem sido a mais indicada e única autorizada para o uso em processos alimentícios para a hidrólise da lactose. O objetivo deste estudo foi avaliar a hidrólise da lactose presente em leite fluido semidesnatado em intervalos de 5 minutos até o tempo final de 60 minutos. Foram realizados dois ensaios distintos sobre a atividade da enzima β-galactosidase: a) usando enzima lactase comercial produzida por Aspergillus orizae e b) usando preparado enzimático contendo lactase de origem microbiana (A. orizae), protease e lipase. A composição do leite foi avaliada utilizando o equipamento Master Mini ® com princípio de funcionamento por ultrassom. A hidrólise provocou alterações em algumas características físico-quimicas do leite, aumento da densidade, sólidos não gordurosos, proteínas, minerais e redução do ponto de congelamento. As duas enzimas mostraram resultados diferentes, visto que uma delas proporcionou maior redução que a outra, entretanto não se alcançou 90%. O valor encontrado no presente estudo foi significativamente inferior ao esperado para um produto voltado aos indivíduos intolerantes a lactose.

Overexpression of lipA or glpD_RuBisCO in the Synechocystis sp. PCC 6803 Mutant Lacking the Aas Gene Enhances Free Fatty-Acid Secretion and Intracellular Lipid Accumulation

Although engineered cyanobacteria for the production of lipids and fatty acids (FAs) are intelligently used as sustainable biofuel resources, intracellularly overproduced FAs disturb cellular homeostasis and eventually generate lethal toxicity. In order to improve their production by enhancing FFAs secretion into a medium, we constructed three engineered Synechocystis 6803 strains including KA (a mutant lacking the aas gene), KAOL (KA overexpressing lipA, encoding lipase A in membrane lipid hydrolysis), and KAOGR (KA overexpressing quadruple glpD/rbcLXS, related to the CBB cycle). Certain contents of intracellular lipids and secreted FFAs of all engineered strains were higher than those of the wild type. Remarkably, the KAOL strain attained the highest level of secreted FFAs by about 21.9%w/DCW at day 5 of normal BG11 cultivation, with a higher growth rate and shorter doubling time. TEM images provided crucial evidence on the morphological changes of the KAOL strain, which accumulated abundant droplets on regions of thylakoid membranes throughout the cell when compared with wild type. On the other hand, BG11-N condition significantly induced contents of both intracellular lipids and secreted FFAs of the KAOL strain up to 37.2 and 24.5%w/DCW, respectively, within 5 days. Then, for the first time, we shone a spotlight onto the overexpression of lipA in the aas mutant of Synechocystis as another potential strategy to achieve higher FFAs secretion with sustainable growth.

Artificial Neural Networks and Response Surface Methodology Approach for Optimization of an Eco-Friendly and Detergent-Stable Lipase Production from Actinomadura Keratinilytica Strain Cpt29

This work mainly focused on the production of an efficient, economical, and eco-friendly lipase (AKL29) from Actinomadura keratinilytica strain Cpt29 isolated from poultry compost in north east of Algeria, for use in detergent industries. AKL29 shows a significant lipase activity (45 U/mL) towards hydrolyzed triacylglycerols, indicating that it is a true lipase. For maximum lipase production the modeling and optimization of potential culture parameters such as incubation temperature, cultivation time, and Tween 80 (v/v) were built using RSM and ANN approaches. The results show that both the two models provided good quality predictions, yet the ANN showed a clear superiority over RSM for both data fitting and estimation capabilities. A 4.1-fold increase in lipase production was recorded under the following optimal condition: incubation temperature (37.9 °C), cultivation time (111 h), and Tween 80 (3.27%, v/v). Furthermore, the partially purified lipase showed good stability, high compatibility, and significant wash performance with various commercial laundry detergents, making this novel lipase a promising potential candidate for detergent industries.

Effect of Defatting and Extraction Solvent on the Antioxidant and Pancreatic Lipase Inhibitory Activities of Extracts from Hermetia illucens and Tenebrio molitor

The production of specific insect extracts with bioactive properties for human health is an emerging and innovative field for the edible insects industry, but there are unexplored extraction factors that might modulate the bioactivity of the extracts. Ultrasound-assisted extracts from T. molitor and H. illucens were produced. Effects of defatting pre-treatment and extraction solvent were evaluated on extraction yield, antioxidant activity and pancreatic lipase inhibitory effect. Chemical characterisation of defatted extracts from H. illucens was performed by GC-MS-FID. Non-defatted extracts showed higher extraction yields. Defatted extracts had similar extraction yields (around 3%). Defatted extracts had higher antioxidant activity, T. molitor being stronger than H. illucens. Antioxidant activity of T. molitor methanol extract was higher than the rest of solvents. Aqueous ethanol improved the antioxidant activity of H. illucens extracts. All extracts inhibited lipase, but no significant effect of defatting and solvent was observed for T. molitor. A significant higher inhibitory activity was observed for H. illucens, the strongest being defatted 100% and 70% ethanol H. illucens extracts. H. illucens extracts contained free amino acids and disaccharides, together with minor fractions of lipids, sterols and organic acids. These results evidence the potential of extracts obtained from edible insects as antioxidants and inhibitors of the pancreatic lipase, a simultaneous multibioactivity that might be favoured by the defatting pre-treatment of the samples and the solvent of extraction.