Dietary resistant starch upregulates total GLP-1 and PYY in a sustained day-long manner through fermentation in rodents

Glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) are anti-diabetes/obesity hormones secreted from the gut after meal ingestion. We have shown that dietary-resistant starch (RS) increased GLP-1 and PYY secretion, but the mechanism remains unknown. RS is a fermentable fiber that lowers the glycemic index of the diet and liberates short-chain fatty acids (SCFAs) through fermentation in the gut. This study investigates the two possible mechanisms by which RS stimulates GLP-1 and PYY secretion: the effect of a meal or glycemic index, and the effect of fermentation. Because GLP-1 and PYY secretions are stimulated by nutrient availability in the gut, the timing of blood sample collections could influence the outcome when two diets with different glycemic indexes are compared. Thus we examined GLP-1 and PYY plasma levels at various time points over a 24-h period in RS-fed rats. In addition, we tested proglucagon (a precursor to GLP-1) and PYY gene expression patterns in specific areas of the gut of RS-fed rats and in an enteroendocrine cell line following exposure to SCFAs in vitro. Our findings are as follows. 1) RS stimulates GLP-1 and PYY secretion in a substantial day-long manner, independent of meal effect or changes in dietary glycemia. 2) Fermentation and the liberation of SCFAs in the lower gut are associated with increased proglucagon and PYY gene expression. 3) Glucose tolerance, an indicator of increased active forms of GLP-1 and PYY, was improved in RS-fed diabetic mice. We conclude that fermentation of RS is most likely the primary mechanism for increased endogenous secretions of total GLP-1 and PYY in rodents. Thus any factor that affects fermentation should be considered when dietary fermentable fiber is used to stimulate GLP-1 and PYY secretion.

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Identification of Differentially Expressed Genes Using cDNA-AFLP During Six Days In Vitro Tuberization of Potato

Zuriat ◽

10.24198/zuriat.v14i1.6751 ◽

2015 ◽

Vol 14 (1) ◽

Author(s):

Nono Carsono ◽

Christian Bachem

Keyword(s):

Gene Expression ◽

Developmental Process ◽

Expression Patterns ◽

Induction Medium ◽

In Vitro Tuberization ◽

Storage Organ ◽

Developmentally Regulated ◽

Study Gene Expression ◽

Differential Pattern

Tuberization in potato is a complex developmental process resulting in the differentiation of stolon into the storage organ, tuber. During tuberization, change in gene expression has been known to occur. To study gene expression during tuberization over the time, in vitro tuberization system provides a suitable tool, due to its synchronous in tuber formation. An early six days axillary bud growing on tuber induction medium is a crucial development since a large number of genes change in their expression patterns during this period. In order to identify, isolate and sequencing the genes which displaying differential pattern between tuberizing and non-tuberizing potato explants during six days in vitro tuberization, cDNA-AFLP fingerprint, method for the visualization of gene expression using cDNA as template which is amplified to generate an RNA-fingerprinting, was used in this experiment. Seventeen primer combinations were chosen based on their expression profile from cDNA-AFLP fingerprint. Forty five TDFs (transcript derived fragment), which displayed differential expressions, were obtained. Tuberizing explants had much more TDFs, which developmentally regulated, than those from non tuberizing explants. Seven TDFs were isolated, cloned and then sequenced. One TDF did not find similarity in the current databases. The nucleotide sequence of TDF F showed best similarity to invertase ezymes from the databases. The homology of six TDFs with known sequences is discussed in this paper.

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Signalling pathways and mechanistic cues highlighted by transcriptomic analysis of primordial, primary, and secondary ovarian follicles in domestic cat

Scientific Reports ◽

10.1038/s41598-021-82051-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shauna Kehoe ◽

Katarina Jewgenow ◽

Paul R. Johnston ◽

Susan Mbedi ◽

Beate C. Braun

Keyword(s):

Gene Expression ◽

Transforming Growth Factor ◽

Ovarian Follicle ◽

Mammalian Species ◽

Expression Patterns ◽

Ovarian Follicles ◽

Domestic Cat ◽

Transcriptional Analysis ◽

Ovarian Folliculogenesis

AbstractIn vitro growth (IVG) of dormant primordial ovarian follicles aims to produce mature competent oocytes for assisted reproduction. Success is dependent on optimal in vitro conditions complemented with an understanding of oocyte and ovarian follicle development in vivo. Complete IVG has not been achieved in any other mammalian species besides mice. Furthermore, ovarian folliculogenesis remains sparsely understood overall. Here, gene expression patterns were characterised by RNA-sequencing in primordial (PrF), primary (PF), and secondary (SF) ovarian follicles from Felis catus (domestic cat) ovaries. Two major transitions were investigated: PrF-PF and PF-SF. Transcriptional analysis revealed a higher proportion in gene expression changes during the PrF-PF transition. Key influencing factors during this transition included the interaction between the extracellular matrix (ECM) and matrix metalloproteinase (MMPs) along with nuclear components such as, histone HIST1H1T (H1.6). Conserved signalling factors and expression patterns previously described during mammalian ovarian folliculogenesis were observed. Species-specific features during domestic cat ovarian folliculogenesis were also found. The signalling pathway terms “PI3K-Akt”, “transforming growth factor-β receptor”, “ErbB”, and “HIF-1” from the functional annotation analysis were studied. Some results highlighted mechanistic cues potentially involved in PrF development in the domestic cat. Overall, this study provides an insight into regulatory factors and pathways during preantral ovarian folliculogenesis in domestic cat.

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Glycemic Index of Gluten-Free Bread and Their Main Ingredients: A Systematic Review and Meta-Analysis

Foods ◽

10.3390/foods10030506 ◽

2021 ◽

Vol 10 (3) ◽

pp. 506

Author(s):

Bernardo Romão ◽

Ana Luísa Falcomer ◽

Gabriela Palos ◽

Sandra Cavalcante ◽

Raquel Braz Assunção Botelho ◽

...

Keyword(s):

Systematic Review ◽

Glycemic Index ◽

Resistant Starch ◽

Web Of Science ◽

Meta Analysis ◽

Gluten Free ◽

Inclusion Criteria ◽

Glycemic Profile

This study aimed to perform a systematic review and meta-analysis of the glycemic index (GI) of gluten-free bread (GFB) and its main ingredients. The systematic review followed PRISMA guidelines, using seven electronic databases (PubMed, EMBASE, Scopus, Science Direct, Web of Science, gray literature research with Google Scholar, and patents with Google Patent tool), from inception to November 2020. Eighteen studies met the inclusion criteria evaluating 132 GFB samples. Five articles tested GI in vivo, eleven in vitro; and two studies tested both methods. The analysis showed that 60.7% (95% CI: 40.2–78.1%) of the samples presented high glycemic indexes, evidencing a high glycemic profile for GFB. Only 18.2% (95% CI: 11.7–27.2%) of the bread samples presented in the studies were classified as a low GI. Meta-analysis presented moderate/low heterogenicity between studies (I2 = 61% and <1% for both high and low GIs) and reinforced the proportion of high GIs. Lower GIs were found in formulations based on Colocasia esculenta flour or enriched with fiber, yogurt and curd cheese, sourdough, psyllium, hydrocolloids, enzymes, fructans, and resistant starch, highlighting the efficacy of these ingredients to lower GFBs’ GI. GFB tends to present high GI, impacting the development of chronic diseases when consumed.

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In Vitro Starch Hydrolysis and Prediction of Glycemic Index (PGI) in “Amala” and Plantain Based Baked Products

Journal of Food Research ◽

10.5539/jfr.v5n2p73 ◽

2016 ◽

Vol 5 (2) ◽

pp. 73 ◽

Cited By ~ 4

Author(s):

Kiin-Kabari David Barine ◽

Giami Sunday Yorte

Keyword(s):

Glycemic Index ◽

Resistant Starch ◽

Kinetic Constant ◽

Bambara Groundnut ◽

Starch Hydrolysis ◽

Protein Concentrate ◽

Significant Difference ◽

Baked Products ◽

Total Starch

<p>Various levels of bambara groundnut protein cocnentrate ranging from 0 to 15% were used in the formulation of plantain paste (Amala) and plantain baked products. ‘Amala’ and cookies were produced from 85% plantain flour and 15% bamabara groundnut protein concentrate, while cakes and bread were produced from 70% wheat flour, 20% plantain flour and 10% bambara groundnut protein concentrate. Starch fractions and <em>in vitro</em> starch hydrolysis of the products were determined. The lowest total starch value was found in plantain flour (51.51%) and highest in cakes (70.62%). There was no significant difference in resistant starch between plantain flour and ‘amala’ (5.22% and 4.99%, respectively). The lowest resistant starch was observed in bread (0.94%), while digestible starch was higher in bread and cakes compared to plantain flour. Higher total starch also resulted in higher digestible starch. The kinetic constant of plantain products showed very low values suggesting generally, higher resistance to enzymatic hydrolysis. The highest hydrolysis index (HI) of 74.85%, and 74.25% were observed in cakes and bread, respectively; which also resulted in higher predicted glycemic index (PGI) of 80.79% (Cakes) and 80.45% (Bread). These values were significantly different from that obtained for ‘amala’ with H1 of 56.40% with a corresponding PGI of 70.67% while cookies recorded HI value of 62.64% and PGI of 74.10%. The lowest HI (53.98%) and PGI (69.35%) was observed in plantain flour. This study showed that the more plantain flour in the product formualtions, the lower the hydrolysis index (HI) and the predicted glycemic index (PGI).</p>

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Ileal short-chain fatty acids inhibit gastric motility by a humoral pathway

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.2000.279.5.g925 ◽

2000 ◽

Vol 279 (5) ◽

pp. G925-G930 ◽

Cited By ~ 76

Author(s):

G. Cuche ◽

J. C. Cuber ◽

C. H. Malbert

Keyword(s):

Gastric Motility ◽

Short Chain Fatty Acid ◽

Peptide Yy ◽

Short Chain Fatty Acids ◽

Short Chain ◽

Maximal Amplitude ◽

Inhibiting Factor ◽

Glucagon Like Peptide ◽

Glucagon Like Peptide 1

The aim of this study was to evaluate the nervous and humoral pathways involved in short-chain fatty acid (SCFA)-induced ileal brake in conscious pigs. The role of extrinsic ileal innervation was evaluated after SCFA infusion in innervated and denervated Babkin's ileal loops, and gastric motility was measured with strain gauges. Peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) concentrations were evaluated in both situations. The possible involvement of absorbed SCFA was tested by using intravenous infusion of acetate. Ileal SCFA infusion in the intact terminal ileum decreased the amplitude of distal and terminal antral contractions (33 ± 1.2 vs. 49 ± 1.2% of the maximal amplitude recorded before infusion) and increased their frequency (1.5 ± 0.11 vs. 1.3 ± 0.10/min). Similar effects were observed during SCFA infusion in ileal innervated and denervated loops (amplitude, 35 ± 1.0 and 34 ± 0.8 vs. 47 ± 1.3 and 43 ± 1.2%; frequency, 1.4 ± 0.07 and 1.6 ± 0.06 vs. 1.1 ± 0.14 and 1.0 ± 0.12/min). Intravenous acetate did not modify the amplitude and frequency of antral contractions. PYY but not GLP-1 concentrations were increased during SCFA infusion in innervated and denervated loops. In conclusion, ileal SCFA inhibit distal gastric motility by a humoral pathway involving the release of an inhibiting factor, which is likely PYY.

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Synthetic gene regulatory networks in the opportunistic human pathogen Streptococcus pneumoniae

10.1101/834689 ◽

2019 ◽

Cited By ~ 1

Author(s):

Robin A. Sorg ◽

Clement Gallay ◽

Jan-Willem Veening

Keyword(s):

Gene Expression ◽

Streptococcus Pneumoniae ◽

Regulatory Networks ◽

Expression Patterns ◽

Combinatorial Libraries ◽

Regulatory Elements ◽

Expression Control ◽

Gene Expression Control

AbstractStreptococcus pneumoniae can cause disease in various human tissues and organs, including the ear, the brain, the blood and the lung, and thus in highly diverse and dynamic environments. It is challenging to study how pneumococci control virulence factor expression, because cues of natural environments and the presence of an immune system are difficult to simulate in vitro. Here, we apply synthetic biology methods to reverse-engineer gene expression control in S. pneumoniae. A selection platform is described that allows for straightforward identification of transcriptional regulatory elements out of combinatorial libraries. We present TetR- and LacI-regulated promoters that show expression ranges of four orders of magnitude. Based on these promoters, regulatory networks of higher complexity are assembled, such as logic AND and IMPLY gates. Finally, we demonstrate single-copy genome-integrated toggle switches that give rise to bimodal population distributions. The tools described here can be used to mimic complex expression patterns, such as the ones found for pneumococcal virulence factors, paving the way for in vivo investigations of the importance of gene expression control on the pathogenicity of S. pneumoniae.

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ZipSeq : Barcoding for Real-time Mapping of Single Cell Transcriptomes

10.1101/2020.02.04.932988 ◽

2020 ◽

Cited By ~ 2

Author(s):

Kenneth H. Hu ◽

John P. Eichorst ◽

Chris S. McGinnis ◽

David M. Patterson ◽

Eric D. Chow ◽

...

Keyword(s):

Gene Expression ◽

Single Cell ◽

Real Time ◽

Dimensional Space ◽

Single Cells ◽

Expression Patterns ◽

Live Cells ◽

Glass Substrates ◽

Complete Mapping

ABSTRACTSpatial transcriptomics seeks to integrate single-cell transcriptomic data within the 3-dimensional space of multicellular biology. Current methods use glass substrates pre-seeded with matrices of barcodes or fluorescence hybridization of a limited number of probes. We developed an alternative approach, called ‘ZipSeq’, that uses patterned illumination and photocaged oligonucleotides to serially print barcodes (Zipcodes) onto live cells within intact tissues, in real-time and with on-the-fly selection of patterns. Using ZipSeq, we mapped gene expression in three settings: in-vitro wound healing, live lymph node sections and in a live tumor microenvironment (TME). In all cases, we discovered new gene expression patterns associated with histological structures. In the TME, this demonstrated a trajectory of myeloid and T cell differentiation, from periphery inward. A variation of ZipSeq efficiently scales to the level of single cells, providing a pathway for complete mapping of live tissues, subsequent to real-time imaging or perturbation.

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GDF-9 and BMP-15 mRNA Levels in Canine Cumulus Cells Related to Cumulus Expansion and the Maturation Process

Animals ◽

10.3390/ani10030462 ◽

2020 ◽

Vol 10 (3) ◽

pp. 462 ◽

Cited By ~ 3

Author(s):

George Ramirez ◽

Jaime Palomino ◽

Karla Aspee ◽

Monica De los Reyes

Keyword(s):

Gene Expression ◽

Estrous Cycle ◽

Expression Patterns ◽

Cumulus Cells ◽

Mrna Levels ◽

Cumulus Expansion ◽

Polymerase Chain ◽

Specific Regulation ◽

Reproductive Phases

The competence to undergo expansion is a characteristic of cumulus cells (CCs). The aim was to investigate the expression of GDF-9 and BMP-15 mRNA in canine cumulus cells in relation to cumulus expansion and meiotic development over the estrous cycle. CCs were recovered from nonmatured and in vitro-matured (IVM) dog cumulus oocyte complexes (COCs), which were obtained from antral follicles at different phases of the estrous cycle. Quantitative real-time polymerase chain reaction (q-PCR) was used to evaluate the relative abundance of GDF-9 and BMP-15 transcripts from the CCs with or without signs of expansion. The results were evaluated by ANOVA and logistic regression. The maturity of the oocyte and the expansion process affected the mRNA levels in CCs. There were differences (p < 0.05) in GDF-9 and BMP-15 gene expression in CCs isolated from nonmatured COCs when comparing the reproductive phases. Lower mRNA levels (p < 0.05) were observed in anestrus and proestrus in comparison to those in estrus and diestrus. In contrast, when comparing GDF-9 mRNA levels in IVM COCs, no differences were found among the phases of the estrous cycle in expanded and nonexpanded CCs (p < 0.05). However, the highest (p < 0.05) BMP-15 gene expression in CCs that did not undergo expansion was exhibited in anestrus and the lowest (p < 0.05) expression was observed in estrus in expanded CCs. Although the stage of the estrous cycle did not affect the second metaphase (MII )rates, the expanded CCs obtained at estrus coexisted with higher percentages of MII (p < 0.05). In conclusion, the differential expression patterns of GDF-9 and BMP-15 mRNA transcripts might be related to cumulus expansion and maturation processes, suggesting specific regulation and temporal changes in their expression.

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187 INCREASED NUMBER OF EXPANDED BOVINE BLASTOCYSTS IN SOF AND CR1 RELATIVE TO KSOM

Reproduction Fertility and Development ◽

10.1071/rdv19n1ab187 ◽

2007 ◽

Vol 19 (1) ◽

pp. 210

Author(s):

D. M. Kohl ◽

R. L. Monson ◽

L. E. Enwall ◽

J. J. Rutledge

Keyword(s):

Gene Expression ◽

Culture Media ◽

Expression Profiles ◽

Expression Patterns ◽

Culture Conditions ◽

Pregnancy Rates ◽

Embryo Morphology ◽

Bovine Embryos ◽

Chi Square Analysis

Assessment of morphological stage grade is a subjective procedure. Stage grade is of vital importance to, among other things, recipient synchrony for the purpose of establishing successful pregnancies. Asynchronous embryo transfer has led to decreases in pregnancy rates (Farin et al. 1995 Biol. Reprod. 52, 676–682) and has been implicated in contributing to large offspring syndrome (Young et al. 1996 Theriogenology 45, 231). Differences in embryo kinetics based on culture conditions have been well documented (Mello et al. 2005 Reprod. Fert. Dev. 17, 221 abst). Whether such differences are the result of species, breed, metabolic stress, sire effects, or separation from an in vivo environment has yet to be determined. The correlation between oxygen respiration rates and embryo morphology as well as embryo diameter in bovine embryos produced in vitro has shown promise in the development of a more objective predictor of embryo quality and perhaps pregnancy initiation (Lopes et al. 2005 Reprod. Fert. Dev. 17, 151 abst). As well, recent examination of gene expression patterns of in vitro-derived bovine embryos seems to indicate that longer periods of in vitro culture are associated with lower rates of embryo survival (Lonergan et al. 2006 Theriogenology 65, 137–152). We hypothesize that differences do exist in the number, rate, and morphological appearance of blastocysts and that these parameters are in large part based on culture conditions in vitro. The objective of this experiment was to determine the timing and distribution of blastocyst formation of in vitro-produced bovine embryos cultured in SOF8, CR18AA, and KSOM8, under a standard incubation environment. Bovine ovaries from a local abattoir were aspirated and matured for 18-22. Oocytes were fertilized with frozen-thawed Percoll-separated semen from a Holstein bull. Presumptive zygotes were vortexed to remove cumulus cells and placed into 3 different culture media in a highly humidified atmosphere containing 20% oxygen, 5% carbon dioxide, and compressed air at 38.5�C. Embryos were evaluated specifically at 168 h post-insemination (Day 7) and assigned a morphological stage grade (IETS) to determine fixed time point differences. A total of 6 complete replicates were performed. Only embryos exhibiting the presence of a blastocoel at this time were documented (early blast, mid-blast, expanded blast). At 168 h post-insemination, there were no significant differences in the total number of embryos reaching early or mid-blast stage in any of the media. However, chi-square analysis revealed an increase in the number of expanded blastocysts in SOF (n = 813) and CR1 (n = 838) treatments compared to KSOM (n = 824; P < 0.0001). Expanded blastocysts in SOF were also greater in number than in CR1 (P < 0.05). Embryo selection based on development to the expanded blastocyst stage on Day 7 may prove useful in increasing pregnancy rates, and may validate qualitative correlations based on oxygen consumption and gene expression profiles for embryos produced in vitro.

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68 GENE EXPRESSION COMPARISONS BETWEEN BOVINE IN VIVO AND CLONED EMBRYOS PRODUCED BY THREE DIFFERENT METHODS

Reproduction Fertility and Development ◽

10.1071/rdv18n2ab68 ◽

2006 ◽

Vol 18 (2) ◽

pp. 142

Author(s):

N. Ruddock ◽

K. Wilson ◽

M. Cooney ◽

R. Tecirlioglu ◽

V. Hall ◽

...

Keyword(s):

Gene Expression ◽

Chromatin Remodeling ◽

Nuclear Transfer ◽

Expression Patterns ◽

Experimental Models ◽

Gene Expression Patterns ◽

Imprinted Genes ◽

Mammalian Embryo

Developmental pathways in the mammalian embryo are profoundly influenced by the epigenetic interaction of the environment and the genome. Loss of epigenetic control has been implicated in aberrant gene expression and altered imprinting patterns with consequence to the physiology and viability of the conceptus. Bovine somatic cell nuclear transfer (SCNT) is contingent on in vitro culture, and both SCNT and culture conditions are known to induce changes in embryonic gene expression patterns. Using these experimental models, this study compared gene expression of Day 7 cloned blastocysts created from three different SCNT protocols using the same cell line, with Day 7 in vivo blastocysts to elucidate mechanisms responsible for variations in phenotypic outcomes. SCNT methods included: (1) traditional SCNT by subzonal injection (SI); (2) handmade cloning (HMC); and (3) modified serial nuclear transfer (SNT), developed within the group. Four imprinted genes (Grb10, Ndn, Nnat, and Ube3a), four chromatin remodeling genes (Cbx1, Cbx3, Smarca4, and Smarcb1) and two genes implicated in polycystic liver disease (Prkcsh and Sec63) were analyzed in single blastocysts from each treatment (n = 5). All blastocysts expressed Actin, Oct-4 and Ifn-tau. All genes were sequence verified. Several genes were expressed ubiquitously across all groups, including Ndn, Ube3a, Cbx1, Cbx3, and Smarcb1. Interestingly, Grb10 was not expressed in two HMCs and one SNT blastocyst. Nnat was weakly expressed in one in vivo blastocyst and in the majority of cloned blastocysts in all groups. Prkcsh and Sec63 were expressed in all but one HMC blastocyst. While gene expression patterns were mostly maintained following SCNT, the imprinted genes Nnat and Grb10 showed instances of differential or abnormal expression in SCNT embryos. The chromatin remodeling genes were maintained in all SCNT treatments. Prkcsh and Sec63 were both absent in one HMC blastocyst, with implications for liver dysfunction, a condition previously reported in abnormal cloned offspring. The variable mRNA expression following SCNT provides an insight into genetic and environmental factors controlling implantation, placentation, organ formation, and fetal growth.

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