The brain-gut axis in gastrointestinal cancers.

Recent developments have given more credence into the brain-gut-microbiota axis and its role in the development of tumor genesis. The microbiota have multiple functions including maintenance of the epithelial barrier, immune response, digestion, cortisol regulation, and control of neurotransmitters and their metabolism [e.g., serotonin, dopamine, noradrenaline and gamma-Aminobutyric Acid (GABA)]. Changes in gut microbiota can interfere with homeostasis leading to dysbiosis microbiota, which is linked to colorectal cancer. Microbiota composition can cause pronounced effect on medical interventions including medications, chemotherapy, and radiation. Altered primary immune system is associated with microbiota disassociation and development of colorectal cancer. This article reviews the current research in brain-gut axis with focus on microbiota and its role in the development of gastrointestinal cancers. We conducted a literature review on PubMed, Cochrane, and Science direct using English language. We begin by reviewing the brain-gut axis and its function and then discuss its effect on the development of gastrointestinal cancers. We reviewed 70 manuscripts and found association between microbiota dysfunction and development of colorectal cancers predisposing to psychiatric manifestations. Lasting disturbances in the microbiota can lead to systemic inflammation with implications on disease development or treatment modifications. These disruptions of the intestinal flora can play an important role in the pathogenesis of cancers. Most psychological reactions to cancer are similar across cancer types but each cancer when examined individually has its own unique features associated with it. Correlation between fear of recurrence and the level of pathological distress is viewed as an indicator of overall adjustment to cancer survival.

Cytokine storm induced new onset depression in patients with COVID-19. A new look into the association between depression and cytokines -two case reports.

BACKGROUND: Depression appears to be a common complication in patients during and post-COVID-19 infection. Understanding the mechanism of action of cytokines such as interleukin-6, interleukin-10 and others in depression and in cytokine storm syndrome, the core component of COVID- 19, could shine a new light on future treatment options for both disorders. OBJECTIVE: This review demonstrates the role of interleukins in COVID-19 pathogenesis and their role in depression. RESULTS: We described cases we have treated as an example for the dual role interleukins have in COVID-19 infection and depression and reviewed approximately 70 articles focusing on the role of interleukins in cytokine storm syndrome and depression. CONCLUSION: This review highlights the key features of cytokines in both diseases. As the scientific community has more time to recover and process the effect of the current pandemic, we believe that additional research will pave the way to diverse pathways to treat depression in these patient and others.