Physiology - Research Publications

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    Sex-specific associations between cardiovascular risk factors and myocardial infarction in patients with type 2 diabetes: TheADVANCE-ONstudy
    Ohkuma, T ; Peters, SAE ; Jun, M ; Harrap, S ; Cooper, M ; Hamet, P ; Poulter, N ; Chalmers, J ; Woodward, M (WILEY, 2020-10)
    AIM: To examine possible sex differences in the excess risk of myocardial infarction (MI) consequent to a range of conventional risk factors in a large-scale international cohort of patients with diabetes, and to quantify these potential differences both on the relative and absolute scales. MATERIALS AND METHODS: Eleven thousand and sixty-five participants (42% women) with type 2 diabetes in the ADVANCE trial and its post-trial follow-up study, ADVANCE-ON, were included. Cox regression models were used to estimate hazard ratios (HRs) for associations between risk factors and MI (fatal and non-fatal) by sex, and the women-to-men ratio of HRs (RHR). RESULTS: Over a median of 9.6 years of follow-up, 719 patients experienced MI. Smoking status, smoking intensity, higher systolic blood pressure (SBP), HbA1c, total and LDL cholesterol, duration of diabetes, triglycerides, body mass index (BMI) and lower HDL cholesterol were associated with an increased risk of MI in both sexes. Furthermore, some variables were associated with a greater relative risk of MI in women than men: RHRs were 1.75 (95% CI: 1.05-2.91) for current smoking, 1.53 (1.00-2.32) for former smoking, 1.18 (1.02-1.37) for SBP, and 1.13 (95% CI, 1.003-1.26) for duration of diabetes. Although incidence rates of MI were higher in men (9.3 per 1000 person-years) compared with women (5.8 per 1000 person-years), rate differences associated with risk factors were greater in women than men, except for HDL cholesterol and BMI. CONCLUSIONS: In patients with type 2 diabetes, smoking, higher SBP and longer duration of diabetes had a greater relative and absolute effect in women than men, highlighting the importance of routine sex-specific approaches and early interventions in women with diabetes.
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    Role of omega-6 and omega-3 fatty acids in fetal programming.
    Shrestha, N ; Sleep, SL ; Cuffe, JSM ; Holland, OJ ; Perkins, AV ; Yau, SY ; McAinch, AJ ; Hryciw, DH (Wiley, 2020-05)
    Maternal nutrition plays a critical role in fetal development and can influence adult onset of disease. Linoleic acid (LA) and alpha-linolenic acid (ALA) are major omega-6 (n-6) and n-3 polyunsaturated fatty acids (PUFA), respectively, that are essential in our diet. LA and ALA are critical for the development of the fetal neurological and immune systems. However, in recent years, the consumption of n-6 PUFA has increased gradually worldwide, and elevated n-6 PUFA consumption may be harmful to human health. Consumption of diets with high levels of n-6 PUFA before or during pregnancy may have detrimental effects on fetal development and may influence overall health of offspring in adulthood. This review discusses the role of n-6 PUFA in fetal programming, the importance of a balance between n-6 and n-3 PUFAs in the maternal diet, and the need of further animal models and human studies that critically evaluate both n-6 and n-3 PUFA contents in diets.
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    The effect of high maternal linoleic acid on endocannabinoid signalling in rodent hearts.
    Sleep, SL ; Shrestha, N ; Cuffe, JSM ; Holland, OJ ; Headrick, JP ; McAinch, AJ ; Hryciw, DH (Cambridge University Press (CUP), 2020-12)
    The endocannabinoid system (ECS), modulated by metabolites of linoleic acid (LA), is important in regulating cardiovascular function. In pregnancy, LA is vital for foetal development. We investigated the effects of elevated LA in H9c2 cardiomyoblasts in vitro and of a high linoleic acid (HLA, 6.21%) or low linoleic acid (LLA, 1.44%) diet during pregnancy in maternal and offspring hearts. H9c2 cell viability was reduced following LA exposure at concentrations between 300 and 1000 µM. HLA diet decreased cannabinoid receptor type 2 (CB2) mRNA expression in foetal hearts from both sexes. However, HLA diet increased CB2 expression in maternal hearts. The mRNA expression of fatty acid amide hydrolase (FAAH) in foetal hearts was higher in females than in males irrespective of diet and N-acyl phosphatidylethanolamine-specific phospholipase D (NAPE-PLD) mRNA expression showed an interaction between diet and sex. Data indicate that a high LA diet alters cell viability and CB2 expression, potentially influencing cardiac function during pregnancy and development of the offspring's heart.
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    Pregnancy and diet-related changes in the maternal gut microbiota following exposure to an elevated linoleic acid diet.
    Shrestha, N ; Sleep, SL ; Cuffe, JSM ; Holland, OJ ; McAinch, AJ ; Dekker Nitert, M ; Hryciw, DH (American Physiological Society, 2020-02-01)
    Dietary intakes of linoleic acid (LA) have increased, including in women of reproductive age. Changes in maternal gut microbiome have been implicated in the metabolic adaptions that occur during pregnancy. We aimed to investigate whether consumption of a diet with elevated LA altered fecal microbiome diversity before and during pregnancy. Female Wistar-Kyoto rats consumed a high-LA diet (HLA: 6.21% of energy) or a low-LA diet (LLA: 1.44% of energy) for 10 wk before mating and during pregnancy. DNA was isolated from fecal samples before pregnancy [embryonic day 0 (E0)], or during pregnancy at E10 and E20. The microbiome composition was assessed with 16S rRNA sequencing. At E0, the beta-diversity of LLA and HLA groups differed with HLA rats having significantly lower abundance of the genera Akkermansia, Peptococcus, Sutterella, and Xo2d06 but higher abundance of Butyricimonas and Coprococcus. Over gestation, in LLA but not HLA rats, there was a reduction in alpha-diversity and an increase in beta-diversity. In the LLA group, the abundance of Akkermansia, Blautia, rc4.4, and Streptococcus decreased over gestation, whereas Coprococcus increased. In the HLA group; only the abundance of Butyricimonas decreased. At E20, there were no differences in alpha- and beta-diversity, and the abundance of Roseburia was significantly increased in the HLA group. In conclusion, consumption of a HLA diet alters gut microbiota composition, as does pregnancy in rats consuming a LLA diet. In pregnancy, consumption of a HLA diet does not alter gut microbiota composition.
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    Shaping the Treatment Paradigm Based on the Current Understanding of the Pathobiology of Multiple Myeloma: An Overview
    Ninkovic, S ; Hang, Q (MDPI, 2020-11)
    Multiple myeloma is an incurable malignancy which despite progressive improvements in overall survival over the last decade remains characterised by recurrent relapse with progressively shorter duration of response and treatment-free intervals with each subsequent treatment. Efforts to unravel the complex and heterogeneous genomic alterations, the marked dysregulation of the immune system and the multifarious interplay between malignant plasma cells and those of the tumour microenvironment have not only led to improved understanding of myelomagenesis and disease progression but have facilitated the rapid development of novel therapeutics including immunotherapies and small molecules bringing us a step closer to therapies that no doubt will extend survival. Novel therapeutic combinations both in the upfront and relapsed setting as well as novel methods to assess response and guide management are rapidly transforming the management of myeloma.
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    The impact of flipped classroom andragogy on student assessment performance and perception of learning experience in two advanced physiology subjects
    Rathner, JA ; Schier, MA (AMER PHYSIOLOGICAL SOC, 2020-03)
    Flipped classroom teaching has been used by many educators to promote active learning in higher education. This andragogy is thought to increase student engagement by making them more accountable for their learning and increase time on task in the classroom. While there are several systematic reviews that point to improved student results, it remains unclear if flipped classrooms have positive learning effects in physiology education. Flipped classroom teaching was introduced in two advanced physiology subjects (advanced neuroscience, semester 1, and cardiorespiratory and renal physiology, semester 2). Changing the mode of content delivery reduced the time students needed to spend listening to lectures by one-third, without sacrificing either learning content or academic standards. Higher pass rates were observed with larger number of students earning distinction and high-distinction grades. Statistically significant improvements in final grades were observed from both subjects (semester 1: 2017, 49.28 ± 20.16; 2018, 53.29 ± 19.77, t268 = 2.058, P = 0.0405; semester 2: 2017, 58.87 ± 21.19; 2018, 67.91 ± 20.40, t111 = 2.306, P = 0.023). Finally, students' perception of their learning experience remained at or above the university benchmarks (median score of >80% for all iterations of the subjects). While the most frequent and persistent area that students suggested could be improved was reduction of content, equal numbers of students commented that no improvement in the subjects was required. Despite the generally positive attitude to recorded didactic teaching content, classroom attendance remained very low, and students did not engage with the active learning content. This suggest that more emphasis needs to be placed on promoting class attendance by developing better active learning content.
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    2020 International Society of Hypertension Global Hypertension Practice Guidelines
    Unger, T ; Borghi, C ; Charchar, F ; Khan, NA ; Poulter, NR ; Prabhakaran, D ; Ramirez, A ; Schlaich, M ; Stergiou, GS ; Tomaszewski, M ; Wainford, RD ; Williams, B ; Schutte, AE (LIPPINCOTT WILLIAMS & WILKINS, 2020-06)
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    Higher fish consumption and lower risk of central nervous system demyelination
    Black, LJ ; Zhao, Y ; Peng, YC ; Sherriff, JL ; Lucas, RM ; van der Mei, I ; Pereira, G (NATURE PUBLISHING GROUP, 2020-05)
    BACKGROUND/OBJECTIVES: The evidence for diet as a risk factor for multiple sclerosis (MS) is inconclusive. We examined the associations between fish consumption and risk of a first clinical diagnosis of central nervous system demyelination (FCD), a common precursor to MS. METHODS: The 2003-2006 Ausimmune Study was a case-control study examining environmental risk factors for FCD, with participants recruited from four regions of Australia and matched on age, sex, and study region. Dietary intake data were collected using a food frequency questionnaire. We used conditional logistic regression models to test associations between fish consumption (total, tinned, grilled, and fried) and risk of FCD (249 cases and 438 controls), adjusting for history of infectious mononucleosis, smoking, serum 25-hydroxyvitamin D concentrations, socio-economic status, omega-3 supplement use, dietary under-reporting, and total energy intake. RESULTS: Higher total fish consumption (per 30 g/day, equivalent to two serves/week) was associated with an 18% reduced risk of FCD (AOR 0.82; 95% CI 0.70, 0.97). While we found no statistically significant associations between grilled and fried fish consumption and risk of FCD, higher tinned fish consumption (per 30 g/day) was associated with a 41% reduced risk of FCD (AOR 0.59; 95% CI 0.39, 0.89). CONCLUSIONS: Tinned fish is predominantly oily, whereas grilled and fried fish are likely to be a combination of oily and white types. Oily fish is high in vitamin D and very long chain polyunsaturated omega-3 fatty acids, both of which may be beneficial in relation to MS.
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    EpiMetal: an open-source graphical web browser tool for easy statistical analyses in epidemiology and metabolomics
    Ekholm, J ; Ohukainen, P ; Kangas, AJ ; Kettunen, J ; Wang, Q ; Karsikas, M ; Khan, AA ; Kingwell, BA ; Kahonen, M ; Lehtimaki, T ; Raitakari, OT ; Jarvelin, M-R ; Meikle, PJ ; Ala-Korpela, M (OXFORD UNIV PRESS, 2020-08)
    MOTIVATION: An intuitive graphical interface that allows statistical analyses and visualizations of extensive data without any knowledge of dedicated statistical software or programming. IMPLEMENTATION: EpiMetal is a single-page web application written in JavaScript, to be used via a modern desktop web browser. GENERAL FEATURES: Standard epidemiological analyses and self-organizing maps for data-driven metabolic profiling are included. Multiple extensive datasets with an arbitrary number of continuous and category variables can be integrated with the software. Any snapshot of the analyses can be saved and shared with others via a www-link. We demonstrate the usage of EpiMetal using pilot data with over 500 quantitative molecular measures for each sample as well as in two large-scale epidemiological cohorts (N >10 000). AVAILABILITY: The software usage exemplar and the pilot data are open access online at [http://EpiMetal.computationalmedicine.fi]. MIT licensed source code is available at the Github repository at [https://github.com/amergin/epimetal].
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    Hypertension and renin-angiotensin system blockers are not associated with expression of angiotensin-converting enzyme 2 (ACE2) in the kidney
    Jiang, X ; Eales, JM ; Scannali, D ; Nazgiewicz, A ; Prestes, P ; Maier, M ; Denniff, M ; Xu, X ; Saluja, S ; Cano-Gamez, E ; Wystrychowski, W ; Szulinska, M ; Antczak, A ; Byars, S ; Skrypnik, D ; Glyda, M ; Krol, R ; Zywiec, J ; Zukowska-Szczechowska, E ; Burrell, LM ; Woolf, AS ; Greenstein, A ; Bogdanski, P ; Keavney, B ; Morris, AP ; Heagerty, A ; Williams, B ; Harrap, SB ; Trynka, G ; Samani, NJ ; Guzik, TJ ; Charchar, FJ ; Tomaszewski, M (OXFORD UNIV PRESS, 2020-12-21)
    AIMS: Angiotensin-converting enzyme 2 (ACE2) is the cellular entry point for severe acute respiratory syndrome coronavirus (SARS-CoV-2)-the cause of coronavirus disease 2019 (COVID-19). However, the effect of renin-angiotensin system (RAS)-inhibition on ACE2 expression in human tissues of key relevance to blood pressure regulation and COVID-19 infection has not previously been reported. METHODS AND RESULTS: We examined how hypertension, its major metabolic co-phenotypes, and antihypertensive medications relate to ACE2 renal expression using information from up to 436 patients whose kidney transcriptomes were characterized by RNA-sequencing. We further validated some of the key observations in other human tissues and/or a controlled experimental model. Our data reveal increasing expression of ACE2 with age in both human lungs and the kidney. We show no association between renal expression of ACE2 and either hypertension or common types of RAS inhibiting drugs. We demonstrate that renal abundance of ACE2 is positively associated with a biochemical index of kidney function and show a strong enrichment for genes responsible for kidney health and disease in ACE2 co-expression analysis. CONCLUSION: Our results indicate that neither hypertension nor antihypertensive treatment is likely to alter the expression of the key entry receptor for SARS-CoV-2 in the human kidney. Our data further suggest that in the absence of SARS-CoV-2 infection, kidney ACE2 is most likely nephro-protective but the age-related increase in its expression within lungs and kidneys may be relevant to the risk of SARS-CoV-2 infection.