Mg. Guzman-Castillo, Alejandra

Introduction: Brain-derived neurotrophic factor (BDNF) is essential for brain physiological processes influencing memory and learning. BDNF levels can be affected by many factors, including stress. Stress increase serum and salivary cortisol levels. Academic stress is of the chronic type. BDNF levels can be measure from serum, plasma or platelets, and there is still no standard methodology, which is relevant to ensure reproducibility and comparability between studies. Hypothesis: (i) BDNF concentrations in serum show greater variability than in plasma. (ii) In college students with academic stress, peripheral BDNF decreases and salivary cortisol increases. Peripheral blood and salivary cortisol sampling, measurements 12 mL of peripheral blood (with and without anticoagulant) will be drawn per participant, separated from plasma or serum and cryopreserved at -80˚C. Additionally, they will be instructed in the collection of 1 mL of saliva samples, which will be centrifuged. Val66Met polymorphism will be performed by allele-specific PCR, while BDNF and salivary cortisol levels will be determined by ELISA. Statistical analysis: (i) descriptive analysis of the variables, through measures of central tendency and dispersion, and the categorical variables through their frequency and percentage. (ii) Then a bivariate analysis will be performed comparing groups using each variable separately. Expected results: We expect to (i) determine the analytical factors that allow a better reproducibility in the measurement of peripheral BDNF, and (ii) the effect of academic stress on BDNF and salivary cortisol levels. General objective: To standardize plasma and serum collection for BDNF levels and to determine whether academic stress affects peripheral BDNF and salivary cortisol levels. Design: Quantitative research, with a non-experimental cross-sectional descriptive design. Participants: Student volunteers. Under convenience sampling, 20 individuals will be included for standardization of plasma and serum collection and between 70 and 80 individuals to determine the effect of academic stress on BDNF and salivary cortisol.

Introduction: Academic stress (AS) is a prevalent challenge faced by university students, potentially affecting molecular indicators such as brain-derived neurotrophic factor (BDNF) and global DNA methylation (G-DNA-M). These indicators could illuminate the physiological ramifications of academic stress. Study Design and Methods: This research followed a quantitative, non-experimental, longitudinal panel design spanning two academic semesters, observing phenomena in their natural context. Students from the Medical Technology program at Universidad de Concepción, Chile were involved, with assessments at the beginning and during heightened academic stress periods. Sample: Of the total participants, 63.0% were females, with an average age of 21.14 years at baseline, and 36.92% were males, averaging 21.36 years. By the study’s conclusion, female participants averaged 21.95 years, and males 22.13 years. Results: Significant differences were observed between initial and final assessments for the SISCO-II Inventory of Academic Stress and Beck Depression Inventory-II, notably in stressor scores, and physical, and psychological reactions. Gender differences emerged in the final physical and psychological reactions. No significant changes were detected between the two assessments in plasma BDNF or G-DNA-M values. A refined predictive model showcased that, on average, there was a 3.56% decrease in females’ plasma BDNF at the final assessment and a 17.14% decrease in males. In the sample, the G-DNA-M percentage at the final assessment increased by 15.06% from the baseline for females and 18.96% for males. Conclusions: The study underscores the physiological impact of academic stress on university students, evidenced by changes in markers like BDNF and G-DNA-M. These findings offer an in-depth understanding of the intricate mechanisms regulating academic stress responses and highlight the need for interventions tailored to mitigate its physiological and psychological effects.