Background Cardiac ischemic/reperfusion (I/R) injury leads to brain damage. A new antihyperlipidemic drug is aimed at inhibiting PCSK 9 (proprotein convertase subtilisin/kexin type 9), a molecule first identified in a neuronal apoptosis paradigm. Thus, the PCSK 9 inhibitor ( PCSK 9i) may play a role in neuronal recovery following cardiac I/R insults. We hypothesize that PCSK 9i attenuates brain damage caused by cardiac I/R via diminishing microglial/astrocytic hyperactivation, β‐amyloid aggregation, and loss of dendritic spine. Methods and Results Adult male rats were divided into 7 groups: (1) control (n=4); (2) PCSK 9i without cardiac I/R (n=4); (3) sham (n=4); and cardiac I/R (n=40). Cardiac I/R rats were divided into 4 subgroups (n=10/subgroup): (1) vehicle; (2) PCSK 9i (10 μg/kg, IV) before ischemia; (3) PCSK 9i during ischemia; and (4) PCSK 9i at the onset of reperfusion. At the end of cardiac I/R protocol, brains were removed to determine microglial and astrocytic activities, β‐amyloid aggravation, and dendritic spine density. The cardiac I/R led to the activation of the brain's innate immunity resulting in increasing Iba1 + microglia, GFAP + astrocytes, and CD 11b + / CD 45 +high cell numbers. However, CD 11b + / CD 45 +low cell numbers were decreased following cardiac I/R. In addition, cardiac I/R led to reduced dendritic spine density, and increased β‐amyloid aggregation. Only the administration of PCSK 9i before ischemia effectively attenuated these deleterious effects on the brain following cardiac I/R. PCSK 9i administration under the physiologic condition did not affect the aforementioned parameters. Conclusions Cardiac I/R injury activated microglial activity in the brain, leading to brain damage. Only the pretreatment with PCSK 9i prevented dendritic spine loss via reduction of microglial activation and Aβ aggregation.

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Obese-insulin resistance following chronic high-fat diet consumption led to cognitive decline through several mechanisms. Moreover, sex hormone deprivation, including estrogen and testosterone, could be a causative factor in inducing cognitive decline. However, comparative studies on the effects of hormone deprivation on the brain are still lacking. Adult Wistar rats from both genders were operated upon (sham operations or orchiectomies/ovariectomies) and given a normal diet or high-fat diet for 4, 8 and 12 weeks. Blood was collected to determine the metabolic parameters. At the end of the experiments, rats were decapitated and their brains were collected to determine brain mitochondrial function, brain oxidative stress, hippocampal plasticity, insulin-induced long-term depression, dendritic spine density and cognition. We found that male and female rats fed a high-fat diet developed obese-insulin resistance by week 8 and brain defects via elevated brain oxidative stress, brain mitochondrial dysfunction, impaired insulin-induced long-term depression, hippocampal dysplasticity, reduced dendritic spine density and cognitive decline by week 12. In normal diet-fed rats, estrogen deprivation, not testosterone deprivation, induced obese-insulin resistance, oxidative stress, brain mitochondrial dysfunction, impaired insulin-induced long-term depression, hippocampal dysplasticity and reduced dendritic spine density. In high-fat–diet-fed rats, estrogen deprivation, not testosterone deprivation, accelerated and aggravated obese-insulin resistance and brain defects at week 8. In conclusion, estrogen deprivation aggravates brain dysfunction more than testosterone deprivation through increased oxidative stress, brain mitochondrial dysfunction, impaired insulin-induced long-term depression and dendritic spine reduction. These findings may explain clinical reports which show more severe cognitive decline in aging females than males with obese-insulin resistance.

Background: Attention deficit hyperactivity disorder (ADHD) is associated with depression among college students, while perceived social support is also associated with depression, especially among young adults. This study aimed to examine to what extent perceived social support mediated the relationship between ADHD symptoms and depressive symptoms. Methods: In total, 124 first year medical students completed the Adult ADHD Self-Report Scale Screener (ASRS), the Patient Health questionnaire-9 and the revised Thai Multidimensional scale of perceived social support reflecting ADHD symptoms, depressive symptoms, and perceive social support, i.e., family members, friends and other significant people, respectively. Structural equation modeling was used to investigate the hypothesized mediation model. Results: ADHD symptoms exhibited a significant indirect effect on depressive symptoms via perceived social support. ADHD symptoms initially had a direct effect on depression; thereafter, it reduced to a non-significance effect after perceived social support was added. The total variance explained by this model was 35.2%. The mediation model with family support as a mediator showed the highest effect size. Conclusions: The study highlighted the importance of perceived social support, particularly family support, on depressive symptoms among young medical students experiencing ADHD symptoms. The model suggests promising relationships for further research on ADHD-related depression and potential treatment in the future.

Background Symptoms of attention deficit hyperactivity disorder (ADHD) are commonly comorbid with depression This study aimed to examine the relationship between ADHD symptoms and depression through perceived family support and to explore whether the magnitude of the relationship depended on the type of family climate of medical students. Methods This cross-sectional study was conducted among 124 first year medical students in Thailand. Participants completed questionnaires on ADHD symptoms, depression, perceived family support, and 9 types of family climate. The questionnaires included the Adult ADHD Self-Report Scale Screener, Patient Health Questionnaire-9, and revised Thai Multidimensional Scale of Perceived Social Support. Mediational analysis was adopted to examine the mediating role of perceived family support in the relationship between ADHD symptoms and depression, while moderation analysis was applied to examine the extent of the relationship depending on family climate. Results The relationship between ADHD symptoms and depression was moderate. Perceived family support partially mediated this relationship after controlling for age and sex. Among the types of family climate, only helpful family climate was a significant moderator of perceived family support and depression. The moderated mediation model increased the variance in depression from 17% by the mediation model to 21%. However, follow-up conditional mediational analysis showed that the indirect effect of ADHD symptoms on depression via perceived family support was not significant and that this effect did not vary linearly as a function of helpful family climate. Conclusion The findings of the study revealed that poor family support might be one risk of developing depression in the context of ADHD symptoms. Further study on providing intervention concerning family support among those with ADHD symptoms should be warranted. In addition, a study on helpful family climate in a larger sample size, in other populations, and in a longitudinal fashion for a more robust conclusion is encouraged.

Objectives Attention deficit hyperactivity disorder (ADHD) is a neurobehavioral development disorder contributed to social difficulties and affective problems. ADHD was evidently related to perceived stress, internet addiction and depression, leading to academic problems. However, ADHD symptoms among young medical student remains underreported. This study aimed to investigate the prevalence of ADHD and explore the association between ADHD symptoms and mental health-related conditions among medical students. Results Among 124 participants of first year medical students in Chiang Mai University, Thailand, 78 (62.9%) were female. The average age was 18.7 (SD 0.7). Thirty-one (25%) were considered as having ADHD symptoms based on the Adult ADHD Self-Report Scale screener (ASRS). The group with ADHD symptoms showed higher scores on the internet addiction test core (t = 3.27, p = .001), perceived stress scale (t = 2.94, p = .004) and Rosenberg Self-esteem Scale (t = 3.04, p = .003). No difference was found between groups regarding depression and perceived social support scores. However, the total score of ASRS appeared to significantly correlate with all these mental health- related variables. The relatively high prevalent may have contributed to invalid items of ASRS, for which a new or revised scale is needed.

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