Giovana Bristot

Impaired endoplasmic reticulum stress response in bipolar disorder: cellular evidence of illness progression.

Bipolar disorder (BD) is a severe chronic psychiatric disorder that has been associated with cellular dysfunctions related to mitochondria, neurotrophin levels, and oxidative stress. Evidence has shown that endoplasmic reticulum (ER) stress may be a common pathway of the cellular changes described in BD. In the present study we assessed unfolded protein response (UPR) and the effects of this cellular process on lymphocytes from patients with BD. We also evaluated whether the stage of chronicity of BD was associated with changes in UPR parameters. Cultured lymphocytes from 30 patients with BD and 32 age- and sex-matched controls were treated with tunicamycin, an ER stressor, for 12 or 24 h to measure levels of UPR-related proteins (GRP78, eIF2α-P, and CHOP) using flow cytometry, and for 48 h to analyse ER stress-induced cell death. In healthy controls but not in patients we found an increase in levels of GRP78, eIF2α-P, and CHOP after ER stress induction. In addition, tunicamycin-induced cell death was significantly higher in patients compared to controls. More importantly, early-stage patients did not differ from controls while the late-stage patients showed an impaired ER stress response. Thus, dysfunction in ER-related stress response may be associated with decreased cellular resilience in BD and illness progression.

Progesterone and its metabolites as therapeutic targets in psychiatric disorders

Introduction: Neurosteroids are molecules that regulate physiological functions of the CNS. There is increasing evidence suggesting that impaired neurosteroid biosynthesis has been associated with distinct psychiatric disorders. This review summarizes data from studies that have investigated the relationship between progesterone (PROG) and psychiatric disorders as well as the mechanisms potentially involved in PROG-induced neuroprotection. Areas covered: The review covers the role of PROG and its metabolites in psychiatric disorders, focusing on results from preclinical and some clinical studies that support the relationship between alterations on PROG levels and pathophysiology of psychiatric illness. We also discussed the main mechanisms underlying the neuroprotective effects of PROG metabolites. Expert opinion: Our review points out the possible relationship between PROG and its metabolites and the pathophysiology of psychiatric disorders. Furthermore, both preclinical and clinical studies show that certain treatments (antidepressants or antipsychotics) may normalize the levels of PROG, suggesting that the amelioration of psychiatric symptoms may occur due to upregulation of PROG metabolites. Therefore, these results give support to new possibilities of treatment for patients with psychiatric symptoms from anxiety- and depressive-like behaviors to aggressive behaviors.

High levels of brain-derived neurotrophic factor are associated with treatment adherence among crack-cocaine users

Due to the complexity of crack -cocaine addiction treatment, the identification of biological markers that could help determining the impact or outcome of drug use has become a major subject of study. Therefore, we aim to evaluate the association of Brain-Derived Neurotrophic Factor (BDNF) and Thiobarbituric Acid Reactive Substances (TBARS) levels in crack -cocaine users with treatment adherence and with drug addiction severity. A sample of 47 male inpatient crack- cocaine users were recruited in a treatment unit, and blood samples were collected at admission and discharge in order to measure BDNF and TBARS serum levels. Subjects were split into 2 groups: treatment non-completers (n=23) and treatment completers (n=24). The completer group had a tendency of higher levels of BDNF than non-completers at admission (16.85±3.24 vs. 14.65±5.45, p=0.10), and significant higher levels at discharge (18.10±4.88 vs. 13.91±4.77, p=0.001). A negative correlation between BDNF levels at admission and years of crack use was observed. We did not find significant changes in TBARS levels during inpatient treatment, although the completer group tended to decrease these levels while non-completers tend to increase it. These findings suggest an association between higher levels of BDNF and better clinical outcomes in crack- cocaine users after detoxification. We believe that the variation in BDNF and TBARS found here add evidence to literature data that propose that such biomarkers could be used to better understand the physiopathology of crack- cocaine addiction.

Clinical staging and serum cytokines in bipolar patients during euthymia

Aims: Changes in serum cytokines and altered neutrophin concentration have been associated with bipolar disorder (BD). Our aim here was to analyze peripheral blood biomarkers according to the clinical stages of BD. Method: Euthymic BD‐I patients were grouped according to their level of functioning in early‐stage (n = 25) and late‐stage (n = 23), and compared to healthy siblings (n = 23) and genetically unrelated healthy controls (n = 21). Neurotrophin (neurotrophin‐3 and BDNF) concentration and biomarkers of inflammation, including cytokines (IL‐6, IL‐10 and TNF‐&agr;), leukocytes count and acute phase proteins, were measured. Results: IL‐10 concentration was significantly increased in early‐stage patients compared to late‐stage patients, healthy siblings and controls whereas TNF‐&agr; concentration was significantly increased in late‐stage patients compared to controls. Total leukocytes, neutrophil and monocyte count were significantly increased in late‐stage patients compared to healthy siblings and controls. The concentration of IL‐6, neurotrophin‐3 and BDNF was unchanged in euthymia. Healthy siblings did not show significant changes in any biomarker. Conclusions: The concentration of IL‐10, TNF‐&agr;, neutrophil and monocytes subtype count in blood is altered in patients with BD during euthymic state. The link between peripheral inflammation and different stages in BD deserves further studies. HIGHLIGHTSThe concentration of IL‐10, TNF‐&agr;, neutrophil, monocytes in blood is altered in patients with bipolar disorder (BD) during euthymia.The changes depend on the clinical stages of BD.There is an association between peripheral inflammation and early‐ and late‐stages of BD during euthymia.

Serum BDNF levels in unaffected first-degree relatives of patients with bipolar disorder

Objective: Unaffected relatives of bipolar disorder (BD) patients have been investigated for the identification of endophenotypes in an attempt to further elucidate the pathophysiology of the disease. Brain-derived neurotrophic factor (BDNF) is considered to be implicated in the pathophysiology of BD, but its role as an endophenotype has been poorly studied. We investigated abnormal serum BDNF levels in BD patients, in their unaffected relatives, and in healthy controls. Methods: BDNF levels were obtained from 25 DSM-IV bipolar I disorder patients, 23 unaffected relatives, and 27 healthy controls. All BD patients were in remission. The unaffected subjects were first-degree relatives of the proband who had no lifetime DSM-IV diagnosis of axis I disorder. BDNF serum levels were determined by sandwich ELISA using monoclonal BDNF-specific antibodies. Results: There were no statistical differences in BDNF levels among BD patients, relatives, and healthy controls. Conclusion: Serum BDNF levels may not indicate high genetic risk for BD, possibly acting as state markers rather than trait markers of the disease.

Oxidative stress markers imbalance in late-life depression

BACKGROUND Oxidative stress has been implicated in the pathophysiology of mood disorders in young adults. However, there is few data to support its role in the elderly. The primary aim of this study was to evaluate whether subjects with late-life depression (LLD) presented with changes in oxidative stress response in comparison with the non-depressed control group. We then explored how oxidative stress markers associated with specific features of LLD, in particular cognitive performance and age of onset of major depressive disorder in these individuals. METHODS We included a convenience sample of 124 individuals, 77 with LLD and 47 non-depressed subjects (Controls). We measure the plasma levels of 6 oxidative stress markers: thiobarbituric acid reactive substances (TBARS), protein carbonil content (PCC), free 8-isoprostane, glutathione peroxidase (GPx) activity, glutathione reductase (GR) activity, and glutathione S-transferase (GST) activity. RESULTS We found that participants with LLD had significantly higher free 8-isoprostane levels (p = 0.003) and lower glutathione peroxidase activity (p = 0.006) compared to controls. Free 8-isoprostane levels were also significantly correlated with worse scores in the initiation/perseverance (r = -0.24, p = 0.01), conceptualization (r = -0.22, p = 0.02) sub-scores, and the total scores (r = -0.21, p = 0.04) on the DRS. CONCLUSIONS Our study provides robust evidence of the imbalance between oxidative stress damage, in particular lipid peroxidation, and anti-oxidative defenses as a mechanism related to LLD, and cognitive impairment in this population. Interventions aiming to reduce oxidative stress damage can have a potential neuroprotective effect for LLD subjects.

Leptin levels and its correlation with crack-cocaine use severity: A preliminary study

BACKGROUND Crack-cocaine is an important public health problem in Brazil and worldwide. It is a potent form of cocaine which results in rapid and damaging stimulating effects on the central nervous system through inhibition of the dopamine transporter. Some studies have suggested that both food and drugs - including crack, can act on the same brain reward mechanisms, altering the dopamine pathways that modulate behavioral responses. Our hypothesis was that leptin, a well-known peptide that modulates energy metabolism and appetite, can be used as a biomarker for drug use. METHODS Anthropometric data, drug use profiles, and leptin serum levels were evaluated in a cross-sectional study of 40 crack-cocaine users. RESULTS Leptin showed an inverse correlation with the severity of crack use, and this correlation remained when corrected by body mass index (BMI) and body composition by bioimpedance (BIA). The majority of subjects were eutrophic or overweight/obese considering BMI and BIA, and these variables were not significantly associated with the severity of crack use, but positively correlated with leptin levels. CONCLUSIONS Our preliminary findings suggest that leptin could be involved in drug use severity, perhaps through pathways similar to those whereby it modulates food intake. Considering the anthropometric parameters, these findings provide additional evidence that low weight is not predominant in crack users.