The Influence of Probiotic Supplementation on Depressive Symptoms, Inflammation, and Oxidative Stress Parameters and Fecal Microbiota in Patients with Depression Depending on Metabolic Syndrome Comorbidity-PRO-DEMET Randomized Study Protocol

Associations between intestinal fatty-acid binding protein and clinical and metabolic characteristics of depression

INTRODUCTION

The topic of increased intestinal permeability is associated with disruption of the intestinal barrier, leading to the "leaky gut" syndrome. Depressive disorders often coexist with abdominal obesity, metabolic syndrome, or its components and complications. Intestinal permeability has been proven to relate to all of the above.

METHODS

In this cross-sectional study, we aimed to assess the "leaky gut" blood biomarker - intestinal fatty acid-binding protein (I-FABP) - in 114 adult patients diagnosed with depressive disorders depending on abdominal obesity comorbidity, depression, anxiety, and stress level, or antidepressant use. The corrected p-value was set at 0.02. We analyzed patients' mental state, diet, anthropometric parameters, metabolic laboratory markers and I-FABP.

RESULTS

There was no difference in circulating I-FABP levels between obese and non-obese patients with depressive disorders (p = 0.648). Similarly, I-FABP levels were not different in patients with different emotional symptoms severity (p = 0.829 for self-assessed depression, p = 0.164 for anxiety, and p = 0.543 for stress). But, I-FABP levels differed significantly between patients treated and not treated with antidepressants (p = 0.011). In general linear model analysis treatment with antidepressants, anxiety severity level, their interaction, along with smoking status, drinks intake, and using dietary supplements were shown to significantly explain I-FABP variance (p < 0.001, R2adj = 0.261).

CONCLUSIONS

Comorbid obesity did not increase intestinal permeability circulating marker, I-FABP, in the population of patients with depressive disorders. Treatment with antidepressants may be connected to higher I-FABP levels. Using dietary supplements, drinks intake, smoking status, or anxiety level may serve as explanatory factors.

Probiotics for the treatment of depression and its comorbidities: A systemic review

Depression is one of the most common psychiatric conditions, characterized by significant and persistent depressed mood and diminished interest, and often coexists with various comorbidities. The underlying mechanism of depression remain elusive, evidenced by the lack of an appreciate therapy. Recent abundant clinical trials and animal studies support the new notion that the gut microbiota has emerged as a novel actor in the pathophysiology of depression, which partakes in bidirectional communication between the gut and the brain through the neuroendocrine, nervous, and immune signaling pathways, collectively known as the microbiota-gut-brain (MGB) axis. Alterations in the gut microbiota can trigger the changes in neurotransmitters, neuroinflammation, and behaviors. With the transition of human microbiome research from studying associations to investigating mechanistic causality, the MGB axis has emerged as a novel therapeutic target in depression and its comorbidities. These novel insights have fueled idea that targeting on the gut microbiota may open new windows for efficient treatment of depression and its comorbidities. Probiotics, live beneficial microorganisms, can be used to modulate gut dysbiosis into a new eubiosis and modify the occurrence and development of depression and its comorbidities. In present review, we summarize recent findings regarding the MGB axis in depression and discuss the potential therapeutic effects of probiotics on depression and its comorbidities.

Kombuchas from green and black teas reduce oxidative stress, liver steatosis and inflammation, and improve glucose metabolism in Wistar rats fed a high-fat high-fructose diet

The aim of this study was to evaluate the effect of green and black tea kombuchas consumption on adiposity, lipid and glucose metabolism, liver steatosis, oxidative stress, and inflammation in Wistar rats fed a high-fat high-fructose (HFHF) diet. Wistar rats, after 8 weeks to induce metabolic alterations, were divided into an AIN-93M control group, HFHF control group, green tea kombucha + HFHF diet (GTK group), and black tea kombucha + HFHF diet (BTK group), for 10 weeks. The kombuchas improved glucose metabolism, plasma total antioxidant capacity, superoxide dismutase activity, and decreased nitric oxide concentration. Moreover, both kombuchas reduced systemic inflammation by decreasing the neutrophil/lymphocyte ratio (NLR), reduced the total adipose tissue and blood triglyceride, and reverted liver steatosis (from grade 2 to 1), besides the modulation of genes related to adipogenesis and β-oxidation. Therefore, kombuchas from green and black teas have bioactive properties that can help control metabolic alterations induced by the HFHF diet.

Probiotics as a Treatment for "Metabolic Depression"? A Rationale for Future Studies

Depression and metabolic diseases often coexist, having several features in common, e.g., chronic low-grade inflammation and intestinal dysbiosis. Different microbiota interventions have been proposed to be used as a treatment for these disorders. In the paper, we review the efficacy of probiotics in depressive disorders, obesity, metabolic syndrome and its liver equivalent based on the published experimental studies, clinical trials and meta-analyses. Probiotics seem to be effective in reducing depressive symptoms when administered in addition to antidepressants. Additionally, probiotics intake may ameliorate some of the clinical components of metabolic diseases. However, standardized methodology regarding probiotics use in clinical trials has not been established yet. In this narrative review, we discuss current knowledge on the recently used methodology with its strengths and limitations and propose criteria that may be implemented to create a new study of the effectiveness of probiotics in depressive disorders comorbid with metabolic abnormalities. We put across our choice on type of study population, probiotics genus, strains, dosages and formulations, intervention period, as well as primary and secondary outcome measures.