Spatially resolved expression landscape and gene-regulatory network of human gastric corpus epithelium

Molecular knowledge of human gastric corpus epithelium remains incomplete. Here, by integrated analyses using single-cell RNA sequencing (scRNA-seq), spatial transcriptomics, and single-cell assay for transposase accessible chromatin sequencing (scATAC-seq) techniques, we uncovered the spatially resolved expression landscape and gene-regulatory network of human gastric corpus epithelium. Specifically, we identified a stem/progenitor cell population in the isthmus of human gastric corpus, where EGF and WNT signaling pathways were activated. Meanwhile, LGR4, but not LGR5, was responsible for the activation of WNT signaling pathway. Importantly, FABP5 and NME1 were identified and validated as crucial for both normal gastric stem/progenitor cells and gastric cancer cells. Finally, we explored the epigenetic regulation of critical genes for gastric corpus epithelium at chromatin state level, and identified several important cell-type-specific transcription factors. In summary, our work provides novel insights to systematically understand the cellular diversity and homeostasis of human gastric corpus epithelium in vivo.

Prophylactic application of laser light restores L-FABP expression in the livers of rats submitted to partial ischemia

OBJECTIVES: The objective of the present study was to evaluate the protective effect of pre-conditioning treatment with laser light on hepatic injury in rats submitted to partial ischemia using mitochondrial function and liver fatty acid binding protein as markers. METHODS: Rats were divided into four groups (n=5): 1) Control, 2) Control + Laser, 3) Partial Ischemia and 4) Partial Ischemia + Laser. Ischemia was induced by clamping the hepatic pedicle of the left and middle lobes of the liver for 60 minutes. Laser light at 660 nm was applied to the liver immediately prior to the induction of ischemia at 22.5 J/cm2, with 30 seconds of illumination at five individual points. The animals were sacrificed after 30 minutes of reperfusion. Blood and liver tissues were collected for analysis of mitochondrial function, determination of malondialdehyde and analysis of fatty acid binding protein expression by Western blot. RESULTS: Mitochondrial function decreased in the Partial Ischemia group, especially during adenosine diphosphate-activated respiration (state 3), and the expression of fatty acid binding protein was also reduced. The application of laser light prevented bioenergetic changes and restored the expression of fatty acid binding protein. CONCLUSION: Prophylactic application of laser light to the livers of rats submitted to partial ischemia was found to have a protective effect in the liver, with normalization of both mitochondrial function and fatty acid binding protein tissue expression.

Temporal profile of intestinal tissue expression of intestinal fatty acid-binding protein in a rat model of necrotizing enterocolitis

OBJECTIVES: Necrotizing enterocolitis is a severe multifactorial intestinal disorder that primarily affects preterm newborns, causing 20-40% mortality and morbidity. Intestinal fatty acid-binding protein has been reported to be a biomarker for the detection of intestinal injuries. Our aim was to assess intestinal tissue injury and the molecular expression of intestinal fatty acid-binding protein over time in a necrotizing enterocolitis model. METHODS: A total of 144 Newborn rats were divided into two groups: 1) Control, which received breastfeeding (n=72) and 2) Necrotizing Enterocolitis, which received formula feeding and underwent hypoxia and hypothermia (n=72). A total of six time points of ischemia (2 times a day for 3 days; 12 pups for each time point) were examined. Samples were collected for analysis of body weight, morphological and histological characteristics, intestinal weight, intestinal weight/body weight ratio, injury grade, and intestinal fatty acid-binding protein levels. RESULTS: Body and intestinal weights were lower in the Necrotizing Enterocolitis group than in the Control group (p<0.005 and p<0.0005, respectively). The intestinal weight/body weight ratio was higher in the Necrotizing Enterocolitis group than in the Control group (p<0.005) only at the sixth ischemia time point. The Necrotizing Enterocolitis group displayed higher expression of intestinal fatty acid-binding protein (p<0.0005) and showed greater tissue damage than the Control group. CONCLUSION: Intestinal fatty acid-binding protein was an efficient marker of ischemic injury to the intestine and a good correlation was demonstrated between the time of ischemic injury and the grade of intestinal injury.

L-FABP and I-FABP expression in newborn rats changes inversely in the model of necrotizing enterocolitis

PURPOSE: To determine the expression of hepatic L-FABP and intestinal I-FABP in an experimental model of necrotizing enterocolitis (NEC) in neonatal rats. METHODS: Newborn Sprague-Dawley rats were divided into four groups: Control (C1) - exclusive breastfeeding at the first and sixth procedures (C6), NEC1 - fed formula milk and submitted to hypoxia and hypothermia at the first and sixth procedures (NEC6). The newborn pups were fed twice a day for three days, for a total of six procedures. Samples were collected for morphometric evaluation (body weight, liver weight, liver weight/body weight ratio, intestinal weight and intestinal/body weight ratio) and for immunohistochemical and Western blotting analysis. The values obtained were analyzed statistically, with the level of significance set at p<0.05. RESULTS: Morphometric measurements showed reduction of body and liver weights in the NEC group (p<0.05). Both immunohistochemistry and western blotting revealed that L-FABP expression in the liver was decreased and I-FABP expression in the ileum was increased in the NEC group (p<0.05). CONCLUSION: L-FABP and I-FABP expression changed inversely in the rat NEC model. These findings can contribute to a better diagnosis of NEC in human newborns. .

Análisis estructural y funcional de proteínas solubles que unen lípidos de parásitos helmintos / Structural and functional analysis of soluble lipid binding proteins from parasitic helminths / Análise estrutural e funcional de proteínas solúveis que ligam lipídios de parasitas helmintos

Los parásitos helmintos producen y secretan una gran variedad de proteínas que unen lípidos (LBPs, del inglés lipid binding proteins) que podrían participar en la obtención de nutrientes tales como ácidos grasos y colesterol desde el hospedador. Asimismo, se postula que las LBPs podrían intervenir en la regulación de la respuesta inmune del hospedador. Conocer más acerca de las estructuras de estas proteínas, así como de sus interacciones con ligandos y membranas, es claramente pertinente para comprender las interacciones parásito-hospedador que ellas pudieran mediar. Por otra parte, dichos estudios permitirán profundizar en el conocimiento de los mecanismos de infección helmíntica y en el papel que estas proteínas juegan en la biología de los helmintos en general. Asimismo, esta información podría contribuir al establecimiento de medidas terapéuticas y de prevención de las enfermedades causadas por estos parásitos.

Helminth parasites produce and secrete a great variety of lipid binding proteins (LBPs) that may participate in the acquisition of nutrients such as fatty acids and cholesterol from their host. It is also postulated that LBPs might interfere in the regulation of the host's immune response. Knowing more about the structure of these proteins as well as their interactions with ligands and membranes is important in order to understand the host-parasite interaction that they could mediate. On the other hand, these studies will contribute to obtain further knowledge about the mechanisms of helminth infection and the role that these proteins play in helminth biology. Moreover, this information would be useful to set new therapeutic and prevention measures for the diseases caused by these parasites.

Os parasitas helmintos produzem e secretam uma grande variedade de proteínas que ligam lipídios, LBPs (Lipid Binding Proteins, por sua sigla em inglês), que poderiam estar envolvidas na obtenção de nutrientes tais como ácidos graxos e colesterol a partir do hospedeiro. Do mesmo modo, é postulado que as LBPs poderiam intervir na regulação da resposta imune do hospedeiro. Saber mais sobre as estruturas dessas proteínas, bem como sobre as suas interações com ligantes e membranas é claramente pertinente para compreender as interações parasita-hospedeiro que elas pudessem mediar. Além disso, estes estudos irão permitir um melhor entendimento dos mecanismos de infecção helmíntica e o papel que estas proteínas desempenham na biologia de helmintos em geral. Também, essa informação poderia ajudar a estabelecer medidas terapêuticas e de prevenção das doenças provocadas por esses parasitas.

Comparative proteomic analysis of the nucleus accumbens during extinction and reinstatement of morphine dependence / Análisis proteómico comparativo del núcleo accumbens durante laextinción y recaída de la dependencia a la morfina

BACKGROUND: The aim of this study was to detect differentially expressed proteins in the nucleus accumbens between the states of extinction and reinstatement of morphine addiction. Numerous studies on the neurobiological mechanisms concerning drug craving and relapse have been reported to date, but data on their relationship with the underlying key molecular mechanisms involved remain limited. METHODS: In this study, 40 male SpragueDawley rats were equally randomized into a saline group and a morphine group. Both groups received drug selfadministration training, after which extinction models were established naturally. The groups were further divided into two subgroups for extinction and reinstatement tests. Cerebral nucleus accumbens masses were measured for total protein extraction. Twodimensional electrophoresis was performed to determine differential protein spots. These differential proteins were then enzymolysed and identified using mass spectrography. RESULTS: The proteins were classified as fatty acidbinding protein, serine/threonine protein phosphatase 2A catalytic subunit beta isoform, serine/threonine protein phosphatase 2A catalytic subunit alpha isoform, serine/threonine protein phosphatase 2A regulatory subunit B² subunit gamma or heat shock protein 90 cochaperone CDC37. CONCLUSION: Significant changes in five proteins were detected between extinction and reinstatement. These proteins are correlated with phosphorylation and the tricarboxylic acid cycle.

ANTECEDENTES: El objetivo de este estudio fue detectar las proteínas diferencialmente expresadas en el núcleo accumbens entre los estados de extinción y recaída de la adicción a la morfina. Hasta la fecha se han reportado numerosos estudios en relación con los mecanismos neurobiológicos del deseo incontenible y recaída en el consumo de drogas, pero los datos sobre su relación con los mecanismos moleculares fundamentales subyacentes implicados, siguen siendo limitados. MÉTODO: En este estudio, 40 ratas machos SpragueDawley fueron por igual asignadas de manera aleatoria a un grupo salino y un grupo de morfina. Ambos grupos recibieron entrenamiento de autoadministración de drogas, después de lo cual se establecieron modelos de extinción de manera natural. A su vez, los grupos fueron luego subdivididos en dos subgrupos para realizar pruebas de extinción y recaída. Se procedió a medir las masas cerebrales del núcleo accumbens para la extracción total de proteína. Se realizó una electroforesis bidimensional para determinar manchas proteicas diferenciales. Estas proteínas diferenciales fueron entonces sometidas a enzimólisis e identificadas mediante espectrografía de masa. RESULTADOS: Las proteínas fueron clasificadas como proteína de unión a ácidos grasos, isoforma beta de la subunidad catalítica serinatreonina proteína fosfatasa 2A, isoforma alfa de la subunidad catalítica serinatreonina proteína fosfatasa 2A, subunidad gamma subunidad B" de la serinatreonina proteína fosfatasa 2A, o la proteína CDC37 cochaperona 90 de choque térmico. CONCLUSIÓN: Se detectaron cambios significativos en cinco proteínas entre la extinción y la recaída. Estas proteínas están correlacionadas con la fosforilación y el ciclo del ácido tricarboxílico.

O papel da proteína ligadora de ácidos graxos como marcador para a detecção do infarto agudo do miocárdio / The paper of fatty acid-binding protein as marker for acute myocardial infarction detection

A proteína ligadora de ácidos graxos (FABP) possui baixo peso molecular (15kDa) e localização citosólica, estando presente em grandes concentrações nas células miocárdicas. Em virtude dessa características, recentemente seu uso tem sido proposto para a detecção precoce do infarto agudo do miocárdio. Aumentos significativos em sua concentração plasmática podem ser observados dentro de três horas do início dos sintomas, com retorno aos valores normais em torno de 24 horas. Além disso, sua sensibilidade e especificidade têm-se mostrado bastante elevadas. Os autores realizam extensa revisão do tema, abordando os principais aspectos desse novo marcador.

The fatty acid-binding protein (FABP) is a low molecular weight cytosolic protein (15kDa), found in high concentrations in myocardial cells. Due to these characteristics, is has recently been proposed its use to detect acute myocardial infarction. Plasmatic concentration values of this protein signicantly increased can be observed within three hours of the beginning of the symptoms and the level returns to normal in about 24 hours. In addition, its sensivity and specificity as biochemical infarction marker are very high. The authors reviewed this theme emphasizing the main positive aspects of this marker.