Serum BDNF and cognitive dysfunction in SLE: findings from a cohort of 111 patients

Associated between cognition, brain-derived neurotrophic factor (BDNF) and macronutrients in normal and overweight postmenopausal women

BDNF is a protein associated with cognitive dysfunction. The aim of the study was to determine the relationship between BDNF and cognitive functions and the intake of macronutrients in postmenopausal women. For this purpose, 72 postmenopausal women were recruited to the study and divided into two subgroups: overweight/obese and normal weight. Using a 3-day food record, nutrition was assessed. The markers studied were the level of BDNF, which was determined from the venous blood serum collected from women, and selected cognitive functions. We observed that in the normal BMI group macronutrient intake was correlated with BDNF levels, and only total fat and carbohydrate intake were inversely correlated with BDNF levels. There were inverse correlations observed among selected parameters of cognitive functioning. In the Ov/Ob group, macronutrient intake correlated with the BDNF level for several variables, e.g. vice versa with total protein, fat and carbohydrate intake, as well as dietary cholesterol. It has also been noted that there are links between the BDNF factor and excessive body weight.

Cognitive dysfunction, depression and serum level of brain-derived neurotrophic factor (BDNF) in Egyptian patients with rheumatoid arthritis

AIM OF THE WORK

To evaluate serum brain-derived neurotrophic factor (BDNF) in Egyptian patients with rheumatoid arthritis (RA) and its relation with cognitive dysfunction.

PATIENTS AND METHODS

The study was carried out on 60 RA patients; 30 were active (group A) and 30 were non active (group B); and 30 controls (group C). RA disease activity was assessed via DAS28 tool, cognitive function via The Montreal Cognitive Assessment and depression via the PHQ depression scale. Serum BDNF levels were measured.

RESULTS

The mean age in group A was 37.8 (±9.37) years with 83.3% females, in group B was 39.97 (±8.04) years with 86.7% females and in group C was 33.17 (±3.6) years with 93.3% females. Abnormal cognitive functions test was detected in 66.7% of group A, 66.7% of group B, and in 23.3% of group C. There was a statistically significant difference in BDNF serum level between both groups of patients (1.58±0.9ng/ml for group A, 1.81±1.17ng/ml for group B) compared with the control group (3.01±1.25ng/ml, p<0.001). There was no statistically significant difference between BDNF and both disease duration and cognitive function, also no statistically significant difference regarding cognitive function, depression, and BNDF levels in patients with and without fibromyalgia. At a cut-off value of <2ng/ml, BDNF detected RA patients with cognitive dysfunction with a sensitivity of 80%, specificity of 96.67%.

CONCLUSION

BDNF can be a potential biomarker of cognitive dysfunction in RA patients.

Cognitive dysfunction in systemic lupus erythematosus is associated with disease activity and oxidative stress: a comparative study with rheumatoid arthritis for identifying biomarkers

BACKGROUND

The prevalence and pathophysiological mechanisms of cognitive deficits (CD) Systemic Lupus Erythematosus (SLE) and Rheumatoid arthritis (RA) are very heterogeneous and poorly understood. We characterized CD in patients with SLE compared with RA patients and healthy controls. We compared the neuropsychological profile of SLE and RA with patients' oxidative/inflammatory biomarkers for CD.

METHODS

We performed a cross-sectional study, including 50 SLE patients, 29 RA patients, and 32 healthy controls. SLEDAI and DAS28 assessed disease activity. SF-36 questionnaire and a battery of cognitive tests were applied to all participants. Blood samples were collected to determine IL-6, S100ß, myeloperoxidase (MPO), malondialdehyde and reduced glutathione (GSH) alterations.

RESULTS

In the SLE group, higher GSH was associated with the absence of CD (With CD = 69 ± 49, Without CD = 112 ± 81, p = 0.030), while higher IL-6 was associated with the presence of CD in the RA group (With CD = 603 ± 173, Without CD = 431 ± 162, p = 0.032). Regarding specific cognitive domains, in SLE higher MPO was associated with poor performance in reasoning and abstraction (p = 0.039), higher IL-6 was associated with poor performance in inhibitory control and attention (p = 0.031), and higher GSH was associated with better performance in memory(p = 0.021). Higher SLEDAI was associated with poor performance in semantic fluency(p = 0.031), inhibitory control, and attention in the SLE group(p = 0.037). In the RA group, higher DAS-28 was associated with poor performance in executive functions(p = 0.016) and phonemic fluency (p = 0.003).

CONCLUSION

SLE patients' disease activity, inflammatory state, and oxidative stress were associated with CD. In RA patients, CD was associated with disease activity and inflammatory state. These results encourage further studies with larger samples aiming to confirm oxidative stress parameters as biomarkers of CD in SLE patients.

Cognitive Dysfunction Biomarkers in Patients With Rheumatoid Arthritis: A Systematic Review

BACKGROUND/OBJECTIVES

During the last years, a growing number of studies have investigated the link between cognitive dysfunction and rheumatoid arthritis (RA), highlighting the potential pathogenic role of several clinical, psychological, and biological factors. We aimed to investigate serological and cerebrospinal fluid biomarkers in humans and its association with cognitive dysfunction in patients with RA.

METHODS

We performed a systematic review using PRISMA (Preferred Reported Items for Systematic Reviews and Meta-analysis) protocol. A systematic search was conducted in the PubMed/MEDLINE, EMBASE, LILACS, Scopus, and Google Scholar databases from inception up to November 2021. The inclusion criteria for studies were defined based on the participants involved, type of exposure, type of comparison group, outcome of interest, and study design.

RESULTS

Five original studies were included, which provided data from 428 participants. Among plasma proteins, SHH was increased and TTR was reduced in patients with mild cognitive impairment; anti-myelin basic protein and anti-myelin oligodendrocyte glycoprotein negatively correlated with memory, executive function, and attention. S100β negatively correlated with memory and executive functions; some lymphocyte subpopulations positively correlated with attention, memory, and executive functions. Interleukin 2 [IL-2], IL-4, IL-6, and tumor necrosis factor α negatively correlated with memory and positively correlated with executive functions. Interleukin 1β negatively correlated with global cognitive dysfunction and positively correlated with logical thinking. Interleukin 10 and brain-derived neurotrophic factor negatively correlated with memory.

CONCLUSION

Despite the relative scarcity of studies on this subject and the heterogeneity of results, we identified possible biomarkers for cognitive deficits in the RA population. Further longitudinal studies are warranted to clarify these associations and the establishment of possible biomarkers for cognitive deficits in RA.

Blood levels of brain-derived neurotrophic factor (BDNF) in systemic lupus erythematous (SLE): a systematic review and meta-analysis

OBJECTIVES

BDNF has been implicated in the pathophysiology of systemic lupus erythematosus (SLE), especially its neuropsychiatric symptoms. The purpose of this study was to investigate the profile of blood BDNF levels in patients with SLE.

METHODS

We searched PubMed, EMBASE, and the Cochrane Library for papers that compared BDNF levels in SLE patients and healthy controls (HCs). The Newcastle-Ottawa scale was used to assess the quality of the included publications, and statistical analyses were carried out using R 4.0.4.

RESULTS

The final analysis included eight studies totaling 323 healthy controls and 658 SLE patients. Meta-analysis did not show statistically significant differences in blood BDNF concentrations in SLE patients compared to HCs (SMD 0.08, 95% CI [ - 1.15; 1.32], P value = 0.89). After removing outliers, there was no significant change in the results: SMD -0.3868 (95% CI [ - 1.17; 0.39], P value = 0.33. Univariate meta-regression analysis revealed that sample size, number of males, NOS score, and mean age of the SLE participants accounted for the heterogeneity of the studies (R² were 26.89%, 16.53%, 18.8%, and 49.96%, respectively).

CONCLUSION

In conclusion, our meta-analysis found no significant association between blood BDNF levels and SLE. The potential role and relevance of BDNF in SLE need to be further examined in higher quality studies.

Gut microbiome and fecal metabolic alteration in systemic lupus erythematosus patients with depression

Background

Mental health disorders in systemic lupus erythematosus (SLE) are gradually getting recognized; however, less is known regarding the actual structure and compositional alterations in gut microbiome and metabolism and the mechanisms of how they affect depression development in SLE patients.

Methods

Twenty-one SLE patients with depression (SLE-d), 17 SLE patients without depression (SLE-nd), and 32 healthy controls (HC) were included in this study. Fecal samples were collected for 16S rRNA gene sequencing and ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) based metabolomics.

Results

The structure of gut microbiome in the SLE-d group changed compared with that in the other two groups. The microbiome composition of SLE-d group showed decreased species richness indices, characterized by low ACE and Chao1 indices, a decrease in the ratio of phylum Firmicutes to Bacteroidetes, genus Faecalibacterium and Roseburia. A downregulation of the metabolite fexofenadine involved in bile secretion was positively correlated with the genus Faecalibacterium, Subdoligranulum and Agathobacter. Compared with the SLE-nd group, the SLE-d group had elevated serum levels of IL-2 and IL-6 and decreased BDNF. Interestingly, abundance of the genus Faecalibacterium and Roseburia was negatively correlated with IL-6, abundance of the genus Roseburia was negatively correlated with IL-2, and abundance of the genus Bacteroides was positively correlated with IL-2.

Conclusion

This study identified specific fecal microbes and their metabolites that may participate in the development of SLE-d. Our findings provide a new perspective for improving depression in SLE patients by regulating the gut-brain axis.

Depression, anxiety, and sleep quality in childhood onset systemic lupus erythematosus and relationship with brain-derived neurotrophic factor

Background

The association between brain-derived neurotrophic factor (BDNF) and systemic lupus erythematosus (SLE) is controversial, and no study investigated the clinical associations of BDNF in patients with childhood onset systemic lupus erythematosus (cSLE). In this study, we aimed to investigate the serum levels of BDNF in patients with cSLE and examine whether a relationship of BDNF exists among depression, anxiety, and sleep quality.

Methods

Thirty patients and age-sex matched healthy controls were included. Depression, anxiety, sleep quality and quality of life were assessed by relevant questionnaires. Disease activity was assessed according to the SLE disease activity index (SLEDAI) and serum BDNF level was measured by the enzyme-linked immunosorbent assay method.

Results

Serum BDNF level was significantly lower in cSLE patients than healthy controls (21981 vs 29905 pg/mL, p = 0.001) and significantly decreased level was observed in active cSLE (SLEDAI >0), then those with SLEDAI = 0 (17110 vs 26852 pg/mL, p = 0.005). Although the scores of the depression, anxiety, sleep quality and quality of life questionnaires were strongly correlated with each other, no correlation was observed with serum BDNF levels.

Conclusions

In patients with cSLE, serum level of BDNF was significantly decreased compared to healthy controls. Our results suggest that serum BDNF levels were not associated with the presence of anxiety, depression and poor sleep quality and might be dictated by the pathophysiological process of SLE rather than mood disorders.