Association of serum retinoic acid with depression in patients with acute ischemic stroke

Association between vitamin A intake and depression among patients with heart failure

AIMS

We aim to investigate the association between vitamin A intake and depression among patients with heart failure (HF).

METHODS AND RESULTS

In this cross-sectional study, data of HF patients were extracted from the National Health and Nutrition Examination Survey (NHANES) 2007-2020. The independent variable was vitamin A intake, and the dependent variable was depression. Weighted univariate and multivariate logistic regression models were performed to explore the association of vitamin A intake with depression in HF patients. A total of 999 HF patients were included, with a mean age of 66.19 (0.51) years, and 566 (52.49%) were male. And 197 patients have depression. Vitamin A intake ≥731.38 mcg was associated with lower incidence of depression [odds ratio (OR) = 0.37; 95% confidence interval (CI): 0.18-0.76] in HF patients. Similarly, the relationship between high vitamin A intake and lower odds of depression were also observed in subgroups of those aged >65 years (OR = 0.16; 95% CI: 0.04-0.55), males (OR = 0.35; 95% CI: 0.14-0.86), without hypertension (OR = 0.25; 95% CI: 0.11-0.58), without diabetes (OR = 0.30; 95% CI: 0.11-0.78), with hyperlipidaemia (OR = 0.23; 95% CI: 0.09-0.64), and with chronic kidney disease (CKD) (OR = 0.32; 95% CI: 0.13-0.80).

CONCLUSIONS

High vitamin A intake was associated with lower odds of depression in HF patients. Appropriate vitamin A supplementation may have potential benefit to the prevention of depression in HF patients. Additional prospective large-scale studies are required to confirm whether or not vitamin A could lead to decrease in depression symptoms.

Use of gene regulatory network analysis to repurpose drugs to treat bipolar disorder

BACKGROUND

Bipolar disorder (BD) presents significant challenges in drug discovery, necessitating alternative approaches. Drug repurposing, leveraging computational techniques and expanding biomedical data, holds promise for identifying novel treatment strategies.

METHODS

This study utilized gene regulatory networks (GRNs) to identify significant regulatory changes in BD, using network-based signatures for drug repurposing. Employing the PANDA algorithm, we investigated the variations in transcription factor-GRNs between individuals with BD and unaffected individuals, incorporating binding motifs, protein interactions, and gene co-expression data. The differences in edge weights between BD and controls were then used as differential network signatures to identify drugs potentially targeting the disease-associated gene signature, employing the CLUEreg tool in the GRAND database.

RESULTS

Using a large RNA-seq dataset of 216 post-mortem brain samples from the CommonMind consortium, we constructed GRNs based on co-expression for individuals with BD and unaffected controls, involving 15,271 genes and 405 TFs. Our analysis highlighted significant influences of these TFs on immune response, energy metabolism, cell signalling, and cell adhesion pathways in the disorder. By employing drug repurposing, we identified 10 promising candidates potentially repurposed as BD treatments.

LIMITATIONS

Non-drug-naïve transcriptomics data, bulk analysis of BD samples, potential bias of GRNs towards well-studied genes.

CONCLUSIONS

Further investigation into repurposing candidates, especially those with preclinical evidence supporting their efficacy, like kaempferol and pramocaine, is warranted to understand their mechanisms of action and effectiveness in treating BD. Additionally, novel targets such as PARP1 and A2b offer opportunities for future research on their relevance to the disorder.

Antivirulence activities of retinoic acids against Staphylococcus aureus

Multidrug-resistant bacteria such as Staphylococcus aureus constitute a global health problem. Gram-positive S. aureus secretes various toxins associated with its pathogenesis, and its biofilm formation plays an important role in antibiotic tolerance and virulence. Hence, we investigated if the metabolites of vitamin A1 might diminish S. aureus biofilm formation and toxin production. Of the three retinoic acids examined, 13-cis-retinoic acid at 10 μg/mL significantly decreased S. aureus biofilm formation without affecting its planktonic cell growth (MIC >400 μg/mL) and also inhibited biofilm formation by Staphylococcus epidermidis (MIC >400 μg/mL), but less affected biofilm formation by a uropathogenic Escherichia coli strain, a Vibrio strain, or a fungal Candida strain. Notably, 13-cis-retinoic acid and all-trans-retinoic acid significantly inhibited the hemolytic activity and staphyloxanthin production by S. aureus. Furthermore, transcriptional analysis disclosed that 13-cis-retinoic acid repressed the expressions of virulence- and biofilm-related genes, such as the two-component arlRS system, α-hemolysin hla, nuclease (nuc1 and nuc2), and psmα (phenol soluble modulins α) in S. aureus. In addition, plant and nematode toxicity assays showed that 13-cis-retinoic acid was only mildly toxic at concentrations many folds higher than its effective antibiofilm concentrations. These findings suggest that metabolites of vitamin A1, particularly 13-cis-retinoic acid, might be useful for suppressing biofilm formation and the virulence characteristics of S. aureus.

Retinoid homeostasis in major depressive disorder

The small, hormone-like molecule retinoic acid (RA) is a vital regulator in several neurobiological processes that are affected in depression. Next to its involvement in dopaminergic signal transduction, neuroinflammation, and neuroendocrine regulation, recent studies highlight the role of RA in homeostatic synaptic plasticity and its link to neuropsychiatric disorders. Furthermore, experimental studies and epidemiological evidence point to the dysregulation of retinoid homeostasis in depression. Based on this evidence, the present study investigated the putative link between retinoid homeostasis and depression in a cohort of 109 patients with major depressive disorder (MDD) and healthy controls. Retinoid homeostasis was defined by several parameters. Serum concentrations of the biologically most active Vitamin A metabolite, all-trans RA (at-RA), and its precursor retinol (ROL) were quantified and the individual in vitro at-RA synthesis and degradation activity was assessed in microsomes of peripheral blood-derived mononuclear cells (PBMC). Additionally, the mRNA expression of enzymes relevant to retinoid signaling, transport, and metabolism were assessed. Patients with MDD had significantly higher ROL serum levels and greater at-RA synthesis activity than healthy controls providing evidence of altered retinoid homeostasis in MDD. Furthermore, MDD-associated alterations in retinoid homeostasis differed between men and women. This study is the first to investigate peripheral retinoid homeostasis in a well-matched cohort of MDD patients and healthy controls, complementing a wealth of preclinical and epidemiological findings that point to a central role of the retinoid system in depression.

Understanding Why Post-Stroke Depression May Be the Norm Rather Than the Exception: The Anatomical and Neuroinflammatory Correlates of Post-Stroke Depression

Ischemic Stroke precedes depression. Post-stroke depression (PSD) is a major driver for poor recovery, negative quality of life, poor rehabilitation outcomes and poor functional ability. In this systematic review, we analysed the inflammatory basis of post-stroke depression, which involves bioenergetic failure, deranged iron homeostasis (calcium influx, Na influx, potassium efflux etc), excitotoxicity, acidotoxicity, disruption of the blood brain barrier, cytokine-mediated cytotoxicity, reactive oxygen mediated toxicity, activation of cyclooxygenase pathway and generation of toxic products. This process subsequently results in cell death, maladapted, persistent neuro-inflammation and deranged neuronal networks in mood-related brain regions. Furthermore, an in-depth review likewise reveals that anatomic structures related to post-stroke depression may be localized to complex circuitries involving the cortical and subcortical regions.