LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 10

Search options

  1. Article ; Online: The protective effects of human milk-derived peptides on the pancreatic islet biology

    Amitoj Singh / Ashwantha Kumar Enjapoori / Yann Gibert / Karen M. Dwyer

    Biology Open, Vol 9, Iss

    2020  Volume 8

    Abstract: Several epidemiological studies support the protective role of breastfeeding in reducing the risk for type 1 diabetes. Human breast milk is the perfect nutrition for infants and contains many complex proteins, lipids and carbohydrates. In this study, we ... ...

    Abstract Several epidemiological studies support the protective role of breastfeeding in reducing the risk for type 1 diabetes. Human breast milk is the perfect nutrition for infants and contains many complex proteins, lipids and carbohydrates. In this study, we examined the physiological effects of human milk-derived opioid peptides, β-casomorphins (BCM), and compared them with bovine-milk-derived opioid peptides on pancreatic hormone regulation and β-cell regeneration. Exposure of wild-type zebrafish embryos to 50 µg/ml of human BCM-5 and -7 from 3 days post fertilisation until 6 days post fertilisation resulted in an increased insulin domain of expression while exposure to bovine BCM-5 and -7 significantly reduced the insulin domain of expression as analysed by whole-mount in situ hybridisation. These changes may be accounted for by reduced insulin expression or β-cell number and were mitigated by the µ-opioid receptor antagonist, naloxone. The effect of BCM on β-cell regeneration was assessed following ablation of β-cells in Tg (ins: CFP-NTR) zebrafish from 3 days post fertilisation to 4 days post fertilisation, followed by exposure of bovine and human BCM-5 and -7 (50 µg/ml) from 4 days post fertilisation until 7 days post fertilisation. The regenerative capacity of β-cells was not impeded following exposure to human BCM-5 and -7, whereas the capacity of β-cells to regenerate following bovine BCM-5 and -7 exposure was reduced. Our data suggest that human BCM-5 and -7 may promote β-cell development and enable the regeneration of β-cells, while the bovine-milk-derived peptides, BCM-5 and -7, play an opposite role. These data may provide some biological explanation for the protective effect of breastfeeding on the development of type 1 diabetes.
    Keywords type 1 diabetes ; β-cell ; regeneration ; human β-casomorphin ; bovine β-casomorphin ; zebrafish ; pancreas ; Science ; Q ; Biology (General) ; QH301-705.5
    Subject code 571
    Language English
    Publishing date 2020-08-01T00:00:00Z
    Publisher The Company of Biologists
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  2. Article ; Online: Potential for Novel Biomarkers in Diabetes-Associated Chronic Kidney Disease

    Ashani Lecamwasam / Elif I. Ekinci / Richard Saffery / Karen M. Dwyer

    Biomedicines, Vol 8, Iss 341, p

    Epigenome, Metabolome, and Gut Microbiome

    2020  Volume 341

    Abstract: Diabetes-associated chronic kidney disease is a pandemic issue. Despite the global increase in the number of individuals with this chronic condition together with increasing morbidity and mortality, there are currently only limited therapeutic options to ...

    Abstract Diabetes-associated chronic kidney disease is a pandemic issue. Despite the global increase in the number of individuals with this chronic condition together with increasing morbidity and mortality, there are currently only limited therapeutic options to slow disease progression. One of the reasons for this is that the current-day “gold standard” biomarkers lack adequate sensitivity and specificity to detect early diabetic chronic kidney disease (CKD). This review focuses on the rapidly evolving areas of epigenetics, metabolomics, and the gut microbiome as potential sources of novel biomarkers in diabetes-associated CKD and discusses their relevance to clinical practice. However, it also highlights the problems associated with many studies within these three areas—namely, the lack of adequately powered longitudinal studies, and the lack of reproducibility of results which impede biomarker development and clinical validation in this complex and susceptible population.
    Keywords diabetes ; chronic kidney disease ; biomarker ; epigenetics ; metabolomics ; gut microbiome ; Biology (General) ; QH301-705.5
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  3. Article ; Online: Gut Microbiome Composition Remains Stable in Individuals with Diabetes-Related Early to Late Stage Chronic Kidney Disease

    Ashani Lecamwasam / Tiffanie M. Nelson / Leni Rivera / Elif I. Ekinci / Richard Saffery / Karen M. Dwyer

    Biomedicines, Vol 9, Iss 19, p

    2021  Volume 19

    Abstract: 1) Background: Individuals with diabetes and chronic kidney disease display gut dysbiosis when compared to healthy controls. However, it is unknown whether there is a change in dysbiosis across the stages of diabetic chronic kidney disease. We ... ...

    Abstract (1) Background: Individuals with diabetes and chronic kidney disease display gut dysbiosis when compared to healthy controls. However, it is unknown whether there is a change in dysbiosis across the stages of diabetic chronic kidney disease. We investigated a cross-sectional study of patients with early and late diabetes associated chronic kidney disease to identify possible microbial differences between these two groups and across each of the stages of diabetic chronic kidney disease. (2) Methods: This cross-sectional study recruited 95 adults. DNA extracted from collected stool samples were used for 16S rRNA sequencing to identify the bacterial community in the gut. (3) Results: The phylum Firmicutes was the most abundant and its mean relative abundance was similar in the early and late chronic kidney disease group, 45.99 ± 0.58% and 49.39 ± 0.55%, respectively. The mean relative abundance for family Bacteroidaceae, was also similar in the early and late group, 29.15 ± 2.02% and 29.16 ± 1.70%, respectively. The lower abundance of Prevotellaceae remained similar across both the early 3.87 ± 1.66% and late 3.36 ± 0.98% diabetic chronic kidney disease groups. (4) Conclusions: The data arising from our cohort of individuals with diabetes associated chronic kidney disease show a predominance of phyla Firmicutes and Bacteroidetes. The families Ruminococcaceae and Bacteroidaceae represent the highest abundance, while the beneficial Prevotellaceae family were reduced in abundance. The most interesting observation is that the relative abundance of these gut microbes does not change across the early and late stages of diabetic chronic kidney disease, suggesting that this is an early event in the development of diabetes associated chronic kidney disease. We hypothesise that the dysbiotic microbiome acquired during the early stages of diabetic chronic kidney disease remains relatively stable and is only one of many risk factors that influence progressive kidney dysfunction.
    Keywords chronic kidney disease ; diabetes ; dysbiosis ; gut microbiome ; microbiota ; Biology (General) ; QH301-705.5
    Subject code 616
    Language English
    Publishing date 2021-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  4. Article ; Online: High glucose levels affect retinal patterning during zebrafish embryogenesis

    Amitoj Singh / Hozana Andrade Castillo / Julie Brown / Jan Kaslin / Karen M. Dwyer / Yann Gibert

    Scientific Reports, Vol 9, Iss 1, Pp 1-

    2019  Volume 13

    Abstract: Abstract Maternal hyperglycaemia has a profound impact on the developing foetus and increases the risk of developing abnormalities like obesity, impaired glucose tolerance and insulin secretory defects in the post-natal life. Increased levels of glucose ... ...

    Abstract Abstract Maternal hyperglycaemia has a profound impact on the developing foetus and increases the risk of developing abnormalities like obesity, impaired glucose tolerance and insulin secretory defects in the post-natal life. Increased levels of glucose in the blood stream due to diabetes causes visual disorders like retinopathy. However, the impact of maternal hyperglycaemia due to pre-existing or gestational diabetes on the developing foetal retina is unknown. The aim of this work was to study the effect of hyperglycaemia on the developing retina using zebrafish as a vertebrate model. Wild-type and transgenic zebrafish embryos were exposed to 0, 4 and 5% D-Glucose in a pulsatile manner to mimic the fluctuations in glycaemia experienced by the developing foetus in pregnant women with diabetes. The zebrafish embryos displayed numerous ocular defects associated with altered retinal cell layer thickness, increased presence of macrophages, and decreased number of Müeller glial and retinal ganglion cells following high-glucose exposure. We have developed a model of gestational hyperglycaemia using the zebrafish embryo to study the effect of hyperglycaemia on the developing embryonic retina. The data suggests that glucose exposure is detrimental to the development of embryonic retina and the legacy of this exposure may extend into adulthood. These data suggest merit in retinal assessment in infants born to mothers with pre-existing and gestational diabetes both in early and adult life.
    Keywords Medicine ; R ; Science ; Q
    Subject code 571
    Language English
    Publishing date 2019-03-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  5. Article ; Online: Clinicians’ perspectives on equity of access to dialysis and kidney transplantation for rural people in Australia

    Allison Tong / Jonathan Craig / Martin Howell / Talia Gutman / Matthew Jose / Rachel Chalmers / Nicole Jane Scholes-Robertson / Karen M Dwyer / Ieyesha Roberts

    BMJ Open, Vol 12, Iss

    a semistructured interview study

    2022  Volume 2

    Keywords Medicine ; R
    Language English
    Publishing date 2022-02-01T00:00:00Z
    Publisher BMJ Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  6. Article: In vivo endogenous proteolysis yielding beta-casein derived bioactive beta-casomorphin peptides in human breast milk for infant nutrition

    Enjapoori, Ashwantha Kumar / Julie A. Sharp / Karen M. Dwyer / Sonja Kukuljan

    Elsevier Ltd Nutrition. 2019 Jan., v. 57

    2019  

    Abstract: Objective Beta-casein is a major protein in breast milk and an important source for several bioactive peptides that are encrypted within the sequence. Beta-casomorphins (BCMs) are short-chain proteolytic peptides that are derived from the beta-casein ... ...

    Abstract Objective Beta-casein is a major protein in breast milk and an important source for several bioactive peptides that are encrypted within the sequence. Beta-casomorphins (BCMs) are short-chain proteolytic peptides that are derived from the beta-casein protein and have opioid effects in newborns. Human milk is known to contain naturally occurring milk-protein-derived bioactive peptides but the identification of naturally occurring beta-casein-derived BCMs in human breast milk has been limited due to difficulties in the detection of BCM peptides, which are small and circulate in low concentrations. Methods The present study aimed to identify the naturally occurring BCM peptides from beta-casein in human breast milk using liquid chromatography-tandem mass spectrometry. The BCM peptides identified in the breast milk were analysed to predict the milk proteases responsible for the cleavage patterns using a computational tool EnzymePredictor. Results In-depth peptidomics analysis of breast milk samples that were collected at different lactation stages during human lactation revealed the presence of BCMs including BCM-8, -9, -10, and -11 as well as precursors and truncated forms of the original peptide, which suggests that milk protease activity in the mammary gland generates biologically relevant BCMs. Conclusions To our knowledge, this is the first report to describe the presence of naturally occurring human BCM-10 and -11 in breast milk. Our study provides evidence of beta-casein-derived BCM peptides in human milk before infant digestion. Proteases that are present in milk are likely specific in their proteolysis of beta-casein. The identified bioactive BCM-8, -9, -10, and -11 as well as the precursor peptides meet the structural requirements to elicit opioid, immunomodulatory, antioxidative, and satiety functions in newborns.
    Keywords beta-casein ; breast milk ; digestion ; enzyme activity ; human lactation ; infant nutrition ; liquid chromatography ; mammary glands ; milk ; neonates ; peptides ; proteinases ; proteolysis ; satiety ; tandem mass spectrometry
    Language English
    Dates of publication 2019-01
    Size p. 259-267.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 639259-3
    ISSN 1873-1244 ; 0899-9007
    ISSN (online) 1873-1244
    ISSN 0899-9007
    DOI 10.1016/j.nut.2018.05.011
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  7. Article ; Online: Ectonucleotidases in Cancer and Inflammation

    John Stagg / Linda F. Thompson / Karen M. Dwyer

    Journal of Biomedicine and Biotechnology, Vol

    2012  Volume 2012

    Keywords Biotechnology ; TP248.13-248.65 ; Medicine ; R
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  8. Article ; Online: DNA methylation profiling of genomic DNA isolated from urine in diabetic chronic kidney disease

    Ashani Lecamwasam / Alexandra Sexton-Oates / Jake Carmody / Elif I Ekinci / Karen M Dwyer / Richard Saffery

    PLoS ONE, Vol 13, Iss 2, p e

    A pilot study.

    2018  Volume 0190280

    Abstract: To characterise the genomic DNA (gDNA) yield from urine and quality of derived methylation data generated from the widely used Illuminia Infinium MethylationEPIC (HM850K) platform and compare this with buffy coat samples.DNA methylation is the most ... ...

    Abstract To characterise the genomic DNA (gDNA) yield from urine and quality of derived methylation data generated from the widely used Illuminia Infinium MethylationEPIC (HM850K) platform and compare this with buffy coat samples.DNA methylation is the most widely studied epigenetic mark and variations in DNA methylation profile have been implicated in diabetes which affects approximately 415 million people worldwide.QIAamp Viral RNA Mini Kit and QIAamp DNA micro kit were used to extract DNA from frozen and fresh urine samples as well as increasing volumes of fresh urine. Matched buffy coats to the frozen urine were also obtained and DNA was extracted from the buffy coats using the QIAamp DNA Mini Kit. Genomic DNA of greater concentration than 20μg/ml were used for methylation analysis using the HM850K array.Irrespective of extraction technique or the use of fresh versus frozen urine samples, limited genomic DNA was obtained using a starting sample volume of 5ml (0-0.86μg/mL). In order to optimize the yield, we increased starting volumes to 50ml fresh urine, which yielded only 0-9.66μg/mL A different kit, QIAamp DNA Micro Kit, was trialled in six fresh urine samples and ten frozen urine samples with inadequate DNA yields from 0-17.7μg/mL and 0-1.6μg/mL respectively. Sufficient genomic DNA was obtained from only 4 of the initial 41 frozen urine samples (10%) for DNA methylation profiling. In comparison, all four buffy coat samples (100%) provided sufficient genomic DNA.High quality data can be obtained provided a sufficient yield of genomic DNA is isolated. Despite optimizing various extraction methodologies, the modest amount of genomic DNA derived from urine, may limit the generalisability of this approach for the identification of DNA methylation biomarkers of chronic diabetic kidney disease.
    Keywords Medicine ; R ; Science ; Q
    Subject code 612
    Language English
    Publishing date 2018-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  9. Article ; Online: The CD39-Adenosinergic Axis in the Pathogenesis of Immune and Nonimmune Diabetes

    Joanne S. J. Chia / Jennifer L. McRae / Peter J. Cowan / Karen M. Dwyer

    Journal of Biomedicine and Biotechnology, Vol

    2012  Volume 2012

    Abstract: Diabetes mellitus encompasses two distinct disease processes: autoimmune Type 1 (T1D) and nonimmune Type 2 (T2D) diabetes. Despite the disparate aetiologies, the disease phenotype of hyperglycemia and the associated complications are similar. In this ... ...

    Abstract Diabetes mellitus encompasses two distinct disease processes: autoimmune Type 1 (T1D) and nonimmune Type 2 (T2D) diabetes. Despite the disparate aetiologies, the disease phenotype of hyperglycemia and the associated complications are similar. In this paper, we discuss the role of the CD39-adenosinergic axis in the pathogenesis of both T1D and T2D, with particular emphasis on the role of CD39 and CD73.
    Keywords Biotechnology ; TP248.13-248.65 ; Medicine ; R
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  10. Article ; Online: The outcome of renal ischemia-reperfusion injury is unchanged in AMPK-β1 deficient mice.

    Peter F Mount / Kurt Gleich / Shanna Tam / Scott A Fraser / Suet-Wan Choy / Karen M Dwyer / Bo Lu / Bryce Van Denderen / Günter Fingerle-Rowson / Richard Bucala / Bruce E Kemp / David A Power

    PLoS ONE, Vol 7, Iss 1, p e

    2012  Volume 29887

    Abstract: AIM: Activation of the master energy-regulator AMP-activated protein kinase (AMPK) in the heart reduces the severity of ischemia-reperfusion injury (IRI) but the role of AMPK in renal IRI is not known. The aim of this study was to determine whether ... ...

    Abstract AIM: Activation of the master energy-regulator AMP-activated protein kinase (AMPK) in the heart reduces the severity of ischemia-reperfusion injury (IRI) but the role of AMPK in renal IRI is not known. The aim of this study was to determine whether activation of AMPK by acute renal ischemia influences the severity of renal IRI. METHODS: AMPK expression and activation and the severity of renal IRI was studied in mice lacking the AMPK β1 subunit and compared to wild type (WT) mice. RESULTS: Basal expression of activated AMPK, phosphorylayed at αThr¹⁷², was markedly reduced by 96% in AMPK-β1⁻/⁻ mice. Acute renal ischaemia caused a 3.2-fold increase in α1-AMPK activity and a 2.5-fold increase in α2-AMPK activity (P<0.001) that was associated with an increase in AMPK phosphorylation of the AMPK-α subunit at Thr¹⁷² and Ser⁴⁸⁵, and increased inhibitory phosphorylation of the AMPK substrate acetyl-CoA carboxylase. After acute renal ischemia AMPK activity was reduced by 66% in AMPK-β1⁻/⁻ mice compared with WT. There was no difference, however, in the severity of renal IRI at 24-hours between AMPK-β1⁻/⁻ and WT mice, as measured by serum urea and creatinine and histological injury score. In the heart, macrophage migration inhibitory factor (MIF) released during IRI contributes to AMPK activation and protects from injury. In the kidney, however, no difference in AMPK activation by acute ischemia was observed between MIF⁻/⁻ and WT mice. Compared with the heart, expression of the MIF receptor CD74 was found to be reduced in the kidney. CONCLUSION: The failure of AMPK activation to influence the outcome of IRI in the kidney contrasts with what is reported in the heart. This difference might be due to a lack of effect of MIF on AMPK activation and lower CD74 expression in the kidney.
    Keywords Medicine ; R ; Science ; Q
    Subject code 616
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top