First-year university students studying medicine and health sciences must acquire and assimilate significant amounts of physiological knowledge, which can result in tedious, passive rote learning. To address such notions and enhance student engagement and interest, we included examples and highlighted luminaries involved in major research and advances in endocrinology within the endocrinology component of a compulsory pathophysiology course in a medical and health sciences program [University of La Réunion (France)]. This intervention focused on the historical discovery of key hormones (secretin and incretins), spanning the discovery of secretin during the early twentieth century up to the role of incretins nearly a century later. Here, we included physiologist Ernest Henry Starling's experimental setup that led to the discovery of secretin, as well as original figures from his article. Moreover, we discussed the various research stages from the discovery of secretin to incretins by including examples of eminent scientists who contributed to these major advances. Students were required to complete preclass readings that included historical elements and completed online questionnaires before attending endocrinology lectures. They could also pose questions on a dedicated online forum. The formal lectures provided an opportunity to further discuss questions posed on the online forum, to provide feedback on incorrectly answered questions, and to address questions posed by students present in classes. Our educational intervention was well received by the students as it contributed to the development of their general scientific literacy and enhanced their understanding of potential career pathways in health-related science and research.NEW & NOTEWORTHY First-year university students must acquire a large amount of information and concepts about the principles of physiology and may find themselves unaware of the underlying discoveries and scholarship that contributed to such knowledge. We recently included historical elements in our classes for first-year medical and health physiology students by highlighting examples of experiments and the contributions of luminaries involved in major research and advances in endocrinology.

Hemorrhagic stroke, particularly intracerebral hemorrhage (ICH), is a highly lethal subtype of stroke, responsible for a poor prognosis and a high rate of disability. ICH is characterized by the extravasation of red blood cells (RBCs) into the central nervous system. Efficient clearance of RBC lysis products is critical. Erythrophagocytosis may serve as a key protective mechanism in mitigating secondary damage of ICH. Interestingly, diabetes is known to promote RBC glycation and to exacerbate the consequences of ICH. However, the link between glycation, RBC clearance and neurological outcomes after ICH is not clear. In this study, we aimed to decipher the role of glycated RBCs in ICH. For this, we used human RBCs glycated by methylglyoxal (MGO), an intermediate product of glycolysis recognized as one of the most potent glycating agents in humans. These glycated RBCs displayed altered morphology, reduced deformability capacity and increased eryptosis. We then proceeded to RBC microinjection into the brain parenchyma of Tg(mpeg1.1:mCherry) zebrafish allowing the visualization of both microglia and macrophages. Although the presence of RBCs in the parenchyma did not affect the increased recruitment of mpeg1.1-positive cells to the injection site compared to vehicle injection, RBC glycation significantly enhanced erythrophagocytosis. In conclusion, we established an innovative model of ICH, and we demonstrated enhanced RBC phagocytosis in the brain under glycated conditions. Further research is needed to understand the consequence of such process in ICH damage. Finally, our model may contribute to the identification of specific neurorestorative therapeutics aimed at improving brain plasticity after stroke in diabetic context.

First-year physiology students can find the subject challenging, struggling to understand abstract concepts without any context. To address this, we introduced a pedagogical intervention for first-year medical and health physiology students that aimed to link abstract concepts and a pathological disorder, together with a discussion of a specific therapeutic intervention. This pedagogical intervention was well received by first-year physiology students who better understood how basic nerve physiology concepts can be applied within the clinical setting.

Objective Inflammatory phenomena and increase in oxidative stress in cell physiopathology progression render therapeutic strategies based on nutritional antioxidants necessary. It was thus aimed at assessing the effectiveness of the pomegranate mesocarp extract (PME) on differentiation of preadipocytes to adipocytes in the presence/absence of hydrogen peroxide (H2O2), a model mimicking insulin resistance. Method The effect of PME on lipid accumulation, protein expression of antioxidant, inflammatory and adipogenic biomarkers, reactive oxygen species production, activity of antioxidant enzymes and secretion of IL-6 has been evaluated during the differentiation of preadipocytes to adipocytes, in the presence or absence of H2O2. Results H2O2 reduced the expression of the regulator of insulin sensitivity PPAR gamma and suppressed adipocyte differentiation. PME counteracted the effect of H2O2. The latter induced a higher level of fat accumulation by promoting the expressions of the adipogenic markers PPAR gamma, C/EBP alpha, FABP4 and CD36 as compared to the control and the H2O2-treated differentiating cells. During the progression of adipogenesis, highest increase (p < 0.05) in IL-6 secretion, by 3.16 and 3.85 folds, was observed on day 2 of differentiation in control and H2O2-treated cells, respectively, compared to day 0. PME significantly decreased (p < 0.01) the secretion of the cytokine in addition to suppressing the expression of NF kappa B. PME also prevented the reduction of superoxide dismutase, catalase and glutathione peroxidase activities that occurred during adipogenesis, by at most 33%, 119% and 42%, respectively. Conclusion These findings indicate that PME efficiently improves insulin sensitivity and can significantly counteract oxidative stress and inflammation.

This study introduced an authentic learning exercise (endocrinology practical exercise) to undergraduate biology students and ascertained whether it changed their views regarding the nature and regularity of breakfast meals. Here, many altered their breakfast dietary habits, which persisted even after the completion of their module. Authentic teaching approaches can therefore trigger relatively long-lasting changes in terms of breakfast behavioral patterns in young people and may also impact the broader society.

Microglia are macrophage-like cells exerting determinant roles in neuroinflammatory and oxidative stress processes during brain regeneration. We used zebrafish as a model of brain plasticity and repair. First, by performing L-plastin (Lcp1) immunohistochemistry and using transgenic Tg(mpeg1.1:GFP) or Tg(mpeg1.1:mCherry) fish, we analyzed the distribution of microglia/immune cells in the whole brain. Specific regional differences were evidenced in terms of microglia/immune cell density and morphology (elongated, branched, highly branched, and amoeboid). Taking advantage of Tg(fli:GFP) and Tg(GFAP::GFP) enabling the detection of endothelial cells and neural stem cells (NSCs), we highlighted the association of elongated microglia/immune cells with blood vessels and rounded/amoeboid microglia with NSCs. Second, after telencephalic injury, we showed that L-plastin cells were still abundantly present at 5 days post-lesion (dpl) and were associated with regenerative neurogenesis. Finally, RNA-sequencing analysis from injured telencephalon (5 dpl) confirmed the upregulation of microglia/immune cell markers and highlighted a significant increase of genes involved in oxidative stress (nox2, nrf2a, and gsr). The analysis of antioxidant activities at 5 dpl also revealed an upregulation of superoxide dismutase and persistent H2O2 generation in the injured telencephalon. Also, microglia/immune cells were shown to be a source of oxidative stress at 5 dpl. Overall, our data provide a better characterization of microglia/immune cell distribution in the healthy zebrafish brain, highlighting some evolutionarily conserved features with mammals. They also emphasize that 5 days after injury, microglia/immune cells are still activated and are associated to a persistent redox imbalance. Together, these data raise the question of the role of oxidative stress in regenerative neurogenesis in zebrafish.

Objective It was aimed at determining which polyphenolic compound(s) in pomegranate mesocarp extract (PME) is liable for the antioxidant, anti-glycation and anti-CD36 activities. Methods The PME was fractionated using liquid-liquid extraction method. The fractions were tested for their polyphenolic content, antioxidant potency, anti-glycation activity and anti-CD36 potential. The metabolite compositions of PME and derived fractions were investigated in an untargeted manner using metabolomics in relation to its antioxidant and anti-glycation activities. Results The ethyl acetate and n-butanol fractions of the pomegranate mesocarp demonstrated highest antioxidant and anti-glycation potencies. These fractions, represented by gallic and ellagic acids monomers, were enriched in tannins and phenolic acids. Orthogonal partial least squares discriminate analysis (OPLS-DA) modeling of ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) metabolite profiles from the different pomegranate mesocarp fractions indicated that gallic and ellagic acids were potential contributors to the antioxidant and anti-glycation effects of the pomegranate mesocarp. At cellular level, the polyphenolic-rich crude extract as well as the ethyl acetate, n-butanol and aqueous residual fractions suppressed the protein expression of CD36. The anti-CD36 activity of these extracts and fractions was attributed to the presence of punicalagin, the ellagitannins that occurred in equal amount in the different fractions. Conclusion This work demonstrated the protective effect of the non-edible part of the pomegranate fruit and showed that gallic and ellagic acids account for the antioxidant and anti-glycation activities while punicalagin is liable for the anti-CD36 activity of PME.

Diabetes is associated with a high mortality rate due to vascular complications. Chronic hyperglycemia in diabetes leads to enhanced oxidative stress and glycation. Here, we explored the impact of glycation on human erythrocyte characteristics and capacity to affect endothelial cell function following erythrophagocytosis. Native and glucose-mediated glycated erythrocytes were prepared and characterized in terms of structural and deformability modifications. Erythrocyte preparations were tested for their binding and phagocytosis capacity as well as the potential functional consequences on human endothelial cell lines and primary cultures. Oxidative modifications were found to be enhanced in glycated erythrocytes after determination of their deformability, advanced glycation end-product content and eryptosis. Erythrophagocytosis by endothelial cells was significantly increased when incubated in the presence of glycated erythrocytes. In addition, higher iron accumulation, oxidative stress and impaired endothelial cell permeability were evidenced in cells previously incubated with glycated erythrocytes. When cultured under flow conditions, cellular integrity was disrupted by glycated erythrocytes at microvessel bifurcations, areas particularly prone to vascular complications. This study provides important new data on the impact of glycation on the structure of erythrocytes and their ability to alter endothelial cell function. Increased erythrophagocytosis may have a deleterious impact on endothelial cell function with adverse consequences on diabetic vascular complications.

Red blood cells (RBC) are the most abundant circulating cell of the human body. RBC are constantly exposed to multiple stresses in the circulation, leading to molecular and structural impairments and death. The physiological process of RBC senescence or ageing is referred to as eryptosis. At the end of their lifespan, aged RBC are recognized and removed from the blood by professional phagocytes via a phenomenon called erythrophagocytosis (EP); the phagocytosis of RBC. Some genetic and acquired diseases can influence eryptosis, thereby affecting RBC lifespan and leading to hemolytic anemia. In some diseases, such as diabetes and atherosclerosis, eryptosis and EP can participate in disease progression with both professional and non-professional phagocytes. Therefore, investigating the process of EP in vivo and in vitro, as well as in different cell types, will not only contribute to the understanding of the physiological steps of EP, but also to the deciphering of the specific mechanisms involving RBC and EP that underlie certain pathologies. In this review, the process of EP is introduced and the different methods for studying EP are discussed together with examples of the experimental procedures and materials required.

Flowering plants from the Syzygium genus have long been used in different ethnomedicinal systems worldwide and have been under scrutiny for their biological activities. Syzygium coriaceum, an endemic plant of Mauritius has been poorly studied for its potential application against cancer. Herein, Syzygium coriaceum leaf extract has been investigated for its anticancer effect against hepatocellular carcinoma (HepG2) cells. The anticancer activity was assessed using cell proliferation assays, flow cytometry, JC-1 mitochondrial membrane potential assay, and the COMET assay. Un-targeted metabolite profiling via ultra-performance liquid chromatography coupled to high-resolution qTOF-MS (UPLC-MS) and aided by molecular networking was employed to identify the crude extract metabolites. S. coriaceum treatment induced a dose-dependent increase in lactate dehydrogenase leakage into the culture media, peaking up to 47% (p ≤ 0.0001), compared to untreated control. Moreover, at 40 μg/mL, S. coriaceum led to 88.1% (p ≤ 0.0001) drop in mitochondrial membrane potential and 5.7% (p ≤ 0.001) increased in the number of the cell population in G0/G1 phase as well as increased (p < 0.05) the proportion of cells undergoing apoptotic/necrotic cell death. More so, at 10 μg/mL, S. coriaceum induced DNA damage which was 19 folds (p < 0.001) higher than that of untreated control cells. Metabolite profiling indicated the presence of 65 metabolites, out of which 59 were identified. Tannins, flavonoids, nitrogenous compounds, and organic acids were the most predominant classes of compounds detected. Our findings showed that the presence of tannins and flavonoids in S. coriaceum leaf extract could account for the multiple mechanisms of actions underlying the antiproliferative effect against HepG2 cells.

Objective It was aimed at comparing the glycating capacities of glucose and ribose in bovine serum albumin (BSA) and anti-glycation activity of pomegranate mesocarp extract (PME). The protective mechanism of PME against ribosylated BSA (BSA(RIB))-induced toxicity was also investigated. Methods BSA was incubated with glucose or ribose in the presence or absence of PME for 15 days. In preadipocytes pretreated with PME, cell viability, ROS production, lipid peroxidation and mitochondrial membrane potential were investigated following 1, 6, 12, 18 and 24 h exposure to BSA(RIB). Nuclear translocation of NF kappa B was assessed at 1 h and 24 h of BSA(RIB) insult. Accumulation of oxidized proteins, activities of intrinsic antioxidant enzymes and IL-6 secretion were also determined after 24 h exposure to BSA(RIB). Results Ribose was a harsher glycating agent as compared to glucose and PME showed strong anti-glycation activity by suppressing (P < 0.05) the increase in levels of fluorescent AGEs, Amadori products, protein carbonyl and advanced oxidation protein products (AOPP). In preadipocytes, BSA(RIB) potentiated pro-apoptotic activity by inhibiting the nuclear translocation of NF kappa B. BSA(RIB) induced a time dependent decrease in cell viability, which was significantly suppressed (P < 0.05) by PME. The extract also significantly reduced (P < 0.05) the time dependent increase in ROS level and associated lipid peroxidation as well as loss in mitochondrial membrane potential caused by BSA(RIB). PME also counteracted the BSA(RIB)-induced accumulation of oxidized proteins, decrease in intrinsic antioxidant activity and IL-6 over-secretion. Conclusions PME showed anti-glycation activity and afforded protection against BSA(RIB)-induced toxicity, oxidative stress and inflammation in preadipocytes.

The development and progression of atherosclerosis (ATH) involves lipid accumulation, oxidative stress and both vascular and blood cell dysfunction. Erythrocytes, the main circulating cells in the body, exert determinant roles in the gas transport between tissues. Erythrocytes have long been considered as simple bystanders in cardiovascular diseases, including ATH. This review highlights recent knowledge concerning the role of erythrocytes being more than just passive gas carriers, as potent contributors to atherosclerotic plaque progression. Erythrocyte physiology and ATH pathology is first described. Then, a specific chapter delineates the numerous links between erythrocytes and atherogenesis. In particular, we discuss the impact of extravasated erythrocytes in plaque iron homeostasis with potential pathological consequences. Hyperglycaemia is recognised as a significant aggravating contributor to the development of ATH. Then, a special focus is made on glycoxidative modifications of erythrocytes and their role in ATH. This chapter includes recent data proposing glycoxidised erythrocytes as putative contributors to enhanced atherothrombosis in diabetic patients.

Diabetes constitutes a major health problem associated with severe complications. In hyperglycemic conditions, chronically increased oxidation and glycation of circulating components lead to advanced glycation end-products (AGEs) formation, a key contributor in diabetes complication progression. In line with literature documenting the beneficial properties of herbal teas, this study evaluates the antioxidant/glycant properties of Antirhea borbonica (Ab). Ab aqueous extract effects were tested on human albumin or erythrocytes submitted to methyl glyoxal-mediated glycoxidative damages. By using mass spectrometry, Ab aqueous extracts revealed to be rich in polyphenols. All tested biomarkers of oxidation and glycation, such as AGE, ketoamine, oxidized thiol groups, were decreased in albumin when glycated in the presence of Ab aqueous extract. Ab extract preserve erythrocyte from methylglyoxal (MGO)-induced damages in terms of restored membrane deformability, reduced oxidative stress and eryptosis phenomenon. Antioxidant capacities of Ab extract on erythrocytes were retrieved in vivo in zebrafish previously infused with MGO. These results bring new evidences on the deleterious impacts of glycation on albumin and erythrocyte in diabetes. Furthermore, it reveals antioxidant and antiglycant properties of Ab that could be used for the dietary modulation of oxidative stress and glycation in hyperglycemic situations.

Diabetes is associated with a dramatic mortality rate due to its vascular complications. Chronic hyperglycemia in diabetes leads to enhanced glycation of erythrocytes and oxidative stress. Even though erythrocytes play a determining role in vascular complications, very little is known about how erythrocyte structure and functionality can be affected by glycation. Our objective was to decipher the impact of glycation on erythrocyte structure, oxidative stress parameters and capacity to interact with cultured human endothelial cells.In vitroglycated erythrocytes were prepared following incubation in the presence of different concentrations of glucose. To get insight into thein vivorelevance of our results, we compared these data to those obtained using red blood cells purified from diabetics or non-diabetics. We measured erythrocyte deformability, susceptibility to hemolysis, reactive oxygen species production and oxidative damage accumulation. Altered structures, redox status and oxidative modifications were increased in glycated erythrocytes. These modifications were associated with reduced antioxidant defence mediated by enzymatic activity. Enhanced erythrocyte phagocytosis by endothelial cells was observed when cultured with glycated erythrocytes, which was associated with increased levels of phosphatidylserine-likely as a result of an eryptosis phenomenon triggered by the hyperglycemic treatment. Most types of oxidative damage identified inin vitroglycated erythrocytes were also observed in red blood cells isolated from diabetics. These results bring new insights into the impact of glycation on erythrocyte structure, oxidative damage and their capacity to interact with endothelial cells, with a possible relevance to diabetes.

Tropical forests constitute a prolific sanctuary of unique floral diversity and potential medicinal sources, however, many of them remain unexplored. The scarcity of rigorous scientific data on the surviving Mascarene endemic taxa renders bioprospecting of this untapped resource of utmost importance. Thus, in view of valorizing the native resource, this study has as its objective to investigate the bioactivities of endemic leaf extracts. Herein, seven Mascarene endemic plants leaves were extracted and evaluated for their in vitro antioxidant properties and antiproliferative effects on a panel of cancer cell lines, using methyl thiazolyl diphenyl-tetrazolium bromide (MTT) and clonogenic cell survival assays. Flow cytometry and comet assay were used to investigate the cell cycle and DNA damaging effects, respectively. Bioassay guided-fractionation coupled with liquid chromatography mass spectrometry (MS), gas chromatography-MS, and nuclear magnetic resonance spectroscopic analysis were used to identify the bioactive compounds. Among the seven plants tested, Terminaliabentzoë was comparatively the most potent antioxidant extract, with significantly (p < 0.05) higher cytotoxic activities. T. bentzoë extract further selectively suppressed the growth of human hepatocellular carcinoma cells and significantly halted the cell cycle progression in the G0/G1 phase, decreased the cells' replicative potential and induced significant DNA damage. In total, 10 phenolic compounds, including punicalagin and ellagic acid, were identified and likely contributed to the extract's potent antioxidant and cytotoxic activities. These results established a promising basis for further in-depth investigations into the potential use of T. bentzoë as a supportive therapy in cancer management.

Tropical forests constitute prolific sanctuary of unique floral diversity and potential medicinal sources, however, many of them remains unexplored. Herein, seven Mascarene endemic plants leaves were extracted and evaluated for their in vitro antioxidant properties and antiproliferative effects on a panel of cancer cell lines using MTT and clonogenic cell survival assay. Flow cytometry and comet assay were used to investigate the cell cycle and DNA damaging effects, respectively. Bioassay guided-fractionation coupled with LC-Mass spectrometry (MS), gas chromatography-MS, and nuclear magnetic resonance spectroscopy analysis were used to identify the bioactive compounds. Among the seven plants tested, Terminalia bentzo&euml; was comparatively the most potent antioxidant extract with significantly (p &lt; 0.05) higher cytotoxic activities. T. bentzo&euml; extract further selectively suppressed the growth of human hepatocellular carcinoma cells and significantly halted the cell cycle progression in G0/G1 phase, decreased the cells replicative potential and induced significant DNA damage. Ten phenolic compounds including punicalagin and ellagic acid were identified and likely contributed to the extract potent antioxidant and cytotoxic activities. These results established a promising basis for further in-depth investigations on the potential use of T. bentzo&euml; as supportive therapy in cancer management.

The Hoabinhian is a distinctive lithic techno-complex of mainland and Island Southeast Asia. Knowledge of its relationships with key patterns of technological change at a global scale has progressed over the last two decades. However, our understanding of the Hoabinhian as an indicator of evolution during Prehistory can be substantially enhanced by examining its regional and chronological variability. Here, we present the characteristics of original Hoabinhian artefacts found in a new open-air site at Houay Pano, near Lak Sip (Luang Prabang province, Laos). This technological study of such a classic assemblage, including sumatraliths dated to 5.5 +/- 0.6 ka, is a major contribution to Laotian prehistory and our understanding of the tempo-spatial variability of the Hoabinhian techno-complex. (C) 2018 Academie des sciences. Published by Elsevier Masson SAS.

Background and aims Atherothrombotic plaques of type 2 diabetic (T2D) patients are characterized by an increased neovascularization and intraplaque hemorrhage. The clearance of erythrocytes may be carried out by vascular cells. We explored the potential of human endothelial cells to bind and phagocyte in vitro aged and/or glycated erythrocytes as well as erythrocytes obtained from diabetic patients. Methods Fresh, aged and glycated-aged erythrocytes from healthy volunteers and T2D patients were tested for their binding and phagocytosis capacity as well as the potential functional consequences on endothelial cells (viability, proliferation and wound healing capacity). Immunohistochemistry was also performed in human carotid atherothrombotic samples (from patients with or without T2D). Results Aging and glycation of erythrocytes induced phosphatidylserine (PS) exposure and oxidative stress leading to enhanced endothelial cell binding and engulfment. Phagocytosis by endothelial cells was more pronounced with aged and glycated erythrocytes than with fresh ones. Phagocytosis was enhanced with T2D versus healthy erythrocytes. Furthermore, endothelial wound healing potential was significantly blunted after exposure to glycated-aged versus fresh erythrocytes. Finally, we show that interactions between erythrocytes and endothelial cells and their potential phagocytosis may occur in vivo, in atherothrombotic conditions, in neovessels and in the luminal endothelial lining. Conclusions Endothelial cells may play an important role in erythrocyte clearance in an atherothrombotic environment. Under diabetic conditions, erythrocyte glycation favors their engulfment by endothelial cells and may participate in endothelial dysfunction, thereby promoting vulnerable atherothrombotic plaques to rupture.

IlluminationsNo stress—better results?Anne-Claire Dorsemans, M. Faadiel Essop, and Emmanuel BourdonAnne-Claire DorsemansUniversité de La Réunion, INSERM, UMR 1188, Diabète Athérothrombose Thérapies Réunion Océan Indien, Plateforme CYROI, Saint Denis de La Réunion, France, M. Faadiel EssopCardio-Metabolic Research Group, Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa, and Emmanuel BourdonUniversité de La Réunion, INSERM, UMR 1188, Diabète Athérothrombose Thérapies Réunion Océan Indien, Plateforme CYROI, Saint Denis de La Réunion, FrancePublished Online:15 Nov 2018https://doi.org/10.1152/advan.00121.2017MoreSectionsPDF (101 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat INTRODUCTIONThere are various definitions for the term “stress” in contemporary civilization. In terms of etymology, it is derived from the Middle English “destresse,” which in turn comes from Old French and the Latin form “stringere,” meaning “to draw tight” (9). Stress can also be defined as a highly coordinated physiological response that is mediated by the neural system in response to environmental stressors. As a result, there are corresponding changes in behavior and cognition that allow adaptation to a changing environment (8). Such stressors can be physical or psychological, each acting on distinct areas of the nervous system to thereby trigger release of stress mediators, such as epinephrine and cortisol (6, 8). Here, activation of the autonomic nervous system and the hypothalamic-pituitary-adrenal axis plays a major role to reestablish homeostasis. However, chronic stress disturbs several components of the stress response that can result in pathophysiological outcomes, such as cardio-metabolic diseases onset (6, 8). By contrast, positive emotions of humor and laughter can elicit physiological changes that are associated with a decreased risk for stress-related diseases (11).As physiology teachers within the higher education sector, a major priority is to strongly develop students to exhibit a strong internal motivation for learning and critical thinking. Although various factors may impact this process, the role of stress (acute and chronic) is a crucial factor that may impact a student’s performance. For example, emotional and psychological stress linked to the exam setting (“exam stress”) results in increased pressure (12) and can trigger pathophysiological responses, such as increased cortisol levels (1) together with perturbations of the immune system (1, 10). For this study, we hypothesized that students’ exposure to a stressful condition (simulating exam stress) will influence their cognition and learning behavior and thereby lead to lower test scores vs. nonstressed compatriots. This study was reviewed and approved by our institutional review board that is constituted by the Biology Departmental Head and the Physiology Course Director. All students who participated in this laboratory exercise signed a consent agreement that allowed for the use of anonymous data for publication.We focused on students in their sixth semester preparing for a Bachelor’s Degree in Biology at the University of La Reunion (France). During the semester, they were instructed on the basics of endocrinology, which consisted of 38 h of formal lecturing, 10 h of classroom exercises, together with three 4-h-long laboratory sessions. Following this, students attended one 2-h-long lecture covering the biology of stress hormones. Data were collected during the last session of the practical course that lasted from 8 AM until 12. Here, students initially assessed their glycemic response following nutritional intake, as previously described by our laboratory (13). Students were divided into working groups (n = 2 per group) containing at least one volunteer, and groups were formed in a randomized manner, i.e., those with a relatively difficult part to complete for their laboratory report (stressed group) vs. those with relatively easy questions (nonstressed group). By employing devices such as glucose meters, test strips, and sterile lancets, the students determined their basal and postprandial glycemia. The glycemic variation was then plotted over time (by each student) and the area under the curve was determined. Each group received a four-page sheet on which to report results obtained, together with their interpretations. The information required for the first three pages of the report was identical for all groups and related to informed consent, area-under-the-curve calculations, and other results, and a section for interpretation and conclusions (for a complete data report, refer to Ref. 13).The practical course was coordinated and managed by a PhD student (ACD) working on the impact of stress and/or hyperglycemia on physiological parameters (3–5). This combination made for an ideal scenario where under- and postgraduate students could interact and thereby contribute to successful teaching and learning outcomes. In support, feedback shows that students’ perceptions of this laboratory exercise were highly positive; for example, some commented:• “It was great! I understood stress can have an impact on my physiology.”• “Well, I did not expect that environmental factors may influence my physiology.”• “I was very interested to learn about the research conducted by the lecturer [ACD] and for sure will read some of her publications.”However, as we were interested in the impact of a stressful condition (simulating exam stress) on student performance, the last page of the report consisted of two components. Here one part consisted of relatively difficult questions relating to figures shown in the publication (13), whereas the other section contained relatively easy questions regarding figures obtained from the same source. Some examples of the “easy” and “difficult” questions are reported in Table 1. This four-page data report was completed by each working group during the laboratory exercise and was submitted to the lecturer at the end of the session. The students also completed the easy and difficult questions in a blinded fashion. Of note, the evaluation concerning the common sections (pages 1–3) was used for student assessment purposes, while the single page containing the easy and difficult questions was not used for assessment. Interestingly, a small but significant reduction in student scores for the laboratory report evaluation was found in the group that tackled the more difficult questions (P < 0.05 vs. “easy questions” group; Fig. 1). It is important to note that final scoring normalization of this test was performed to avoid students tackling the harder questions being penalized.Table 1. Example of easy and difficult questions on the students’ report sheetEasyDifficultWhat is the highest blood glucose value?What does the abbreviation SE refer to? Explain.In a sentence or two, briefly comment on the student data table.Calculate the percent change in each parameter measured by individual by sex. Comment. What is P < 0.0001? Explain.Is there a correlation between %body fat and body mass index (BMI)?Is there a correlation between body mass index (BMI) and glycemic response (area under the curve)? Justify. Does an r = 0.466 and a P < 0.05 seem correct to you? What interpretation should be made of this figure?The questions refer to data and figures in Tarnus and Bourdon (13).Fig. 1.Mean score performance of stressed and no-stressed students. Values are means ± SD for student volunteers (n = 34–39 per group). *P < 0.05 indicates a significant difference by using Student’s t-test for unpaired samples (P = 0.018).Download figureDownload PowerPointAs researchers in the diabetes field, it is a key aim to enhance teaching methodologies and styles by actively engaging students with interesting research-type questions. The students correlated sedentary lifestyle or body composition (fat mass percentage) with glycemic responses to dietary intake (13) and/or with maximum oxygen uptake (14). However, we did not observe a large impact of stress on student glycemic responses. This was surprising, as we expected the stress response to increase systemic glucose levels, as would be predicted. Thus we propose these data likely due to 1) the relatively low-grade stressor here employed (nonexam setting vs. more relaxed ambience in practical sessions), and 2) the relatively small sample size of this study. As far as we could ascertain, the students all actively participated in the laboratory exercise and tried their best to respond to the questions posed. Thus we propose that our students experienced relatively low-stress conditions with limited physiological changes. Of note, Haussmann’s group (7) found increased cortisol salivary concentrations after students were submitted to stressful situations. However, their experimental conditions and stressors (presentations, fasting, or competition tests) were far more intense compared with ours. Moreover, we were unable to complete similar measurements during our practical session.For this study, we observed a small but significant impact of a relatively moderate “exam-type” stress on student behavior and scores. Here it is crucial to consider the effects of self-confidence on learning outcomes, as well as the importance of suitable learning spaces on success. As the relationship between arousal level (stress) and performance constitutes an inverted U-shaped curve, performance increases as arousal increases. This relationship is, however, only valid to a specific threshold, after which further increases in stress intensity result in decreased performances (2). We, therefore, propose that additional efforts be made by lecturers to take into account the social view of learning and hence to be mindful of factors such as self-confidence and emotional intelligence and to better use active learning strategies within suitable learning spaces. Together, this should help with the student’s self-management of emotional stress within the exam setting and when dealing with harder questions.GRANTSThis work was supported by the Ministère de l’Enseignement Supérieur et de la Recherche, the Ministère de l’Outre-Mer, the Conseil Régional de La Réunion l’Europe, and the Université de La Réunion. A. C. Dorsemans is a recipient of a fellowship grant from the Ministère de l’Education Nationale, de l’Enseignement Supérieur, et de la Recherche, La Réunion University (Contrat Doctoral).DISCLOSURESNo conflicts of interest, financial or otherwise, are declared by the authors.AUTHOR CONTRIBUTIONSA.-C.D. performed experiments; A.-C.D. and E.B. analyzed data; A.-C.D. and E.B. interpreted results of experiments; A.-C.D. and E.B. prepared figures; A.-C.D., M.F.E., and E.B. drafted manuscript; A.-C.D., M.F.E., and E.B. edited and revised manuscript; A.-C.D., M.F.E., and E.B. approved final version of manuscript.ACKNOWLEDGMENTSThe authors thank all of the students from the University of La Reunion (France) who took part in our courses.REFERENCES1. Assaf AM. Stress-induced immune-related diseases and health outcomes of pharmacy students: A pilot study. Saudi Pharm J 21: 35–44, 2013. doi:10.1016/j.jsps.2012.02.006. Crossref | PubMed | ISI | Google Scholar2. Bardi M, Koone T, Mewaldt S, O’Connor K. 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The long-acting glucagon-like peptide-1 analogue liraglutide has proven efficiency in the management of type 2 diabetes and also has beneficial effects on cardiovascular diseases. Liraglutide's protracted action highly depends on its capacity to bind to albumin via its palmitic acid part. However, in diabetes, albumin can undergo glycation, resulting in impaired drug binding. Our objective in this study was to assess the impact of human serum albumin (HSA) glycation on liraglutide affinity. Using fluorine labeling of the drug and 19F NMR, we determined HSA affinity for liraglutide in two glycated albumin models. We either glycated HSA in vitro by incubation with glucose (G25- or G100-HSA) or methylglyoxal (MGO-HSA) or purified in vivo glycated HSA from the plasma of diabetic patients with poor glycemic control. Nonglycated commercial HSA (G0-HSA) and HSA purified from plasma of healthy individuals served as controls. We found that glycation decreases affinity for liraglutide by 7-fold for G100-HSA and by 5-fold for MGO-HSA compared with G0-HSA. A similarly reduced affinity was observed for HSA purified from diabetic individuals compared with HSA from healthy individuals. Our results reveal that glycation significantly impairs HSA affinity to liraglutide and confirm that glycation contributes to liraglutide's variable therapeutic efficiency, depending on diabetes stage. Because diabetes is a progressive disease, the effect of glycated albumin on liraglutide affinity found here is important to consider when diabetes is managed with this drug.