In response to a peripheral infection, innate immune cells produce pro-inflammatory cytokines that act on the brain to cause sickness behaviour. When activation of the peripheral immune system continues unabated, such as during systemic infections, cancer or autoimmune diseases, the ensuing immune signalling to the brain can lead to an exacerbation of sickness and the development of symptoms of depression in vulnerable individuals. These phenomena might account for the increased prevalence of clinical depression in physically ill people. Inflammation is therefore an important biological event that might increase the risk of major depressive episodes, much like the more traditional psychosocial factors.

/pdf/from-inflammation-to-sickness-and-depression-when-the-immune-maw2hn72o8.pdf

From inflammation to sickness and depression: when the immune system subjugates the brain

http://www.smhc.org.cn/uploadfiles/2014/09/20140929090442442.pdf

A Meta-Analysis of Cytokines in Major Depression

http://dcawatch.com/wp-content/uploads/2012/06/pdf-of-original-paper-on-DCA-submitted-to-the-publication-Cancer-Cell2.pdf

A Mitochondria-K+ Channel Axis Is Suppressed in Cancer and Its Normalization Promotes Apoptosis and Inhibits Cancer Growth

Bacterial colonisation of the intestine has a major role in the post-natal development and maturation of the immune and endocrine systems. These processes are key factors underpinning central nervous system (CNS) signalling. Regulation of the microbiome-gut-brain axis is essential for maintaining homeostasis, including that of the CNS. However, there is a paucity of data pertaining to the influence of microbiome on the serotonergic system. Germ-free (GF) animals represent an effective preclinical tool to investigate such phenomena. Here we show that male GF animals have a significant elevation in the hippocampal concentration of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid, its main metabolite, compared with conventionally colonised control animals. Moreover, this alteration is sex specific in contrast with the immunological and neuroendocrine effects which are evident in both sexes. Concentrations of tryptophan, the precursor of serotonin, are increased in the plasma of male GF animals, suggesting a humoral route through which the microbiota can influence CNS serotonergic neurotransmission. Interestingly, colonisation of the GF animals post weaning is insufficient to reverse the CNS neurochemical consequences in adulthood of an absent microbiota in early life despite the peripheral availability of tryptophan being restored to baseline values. In addition, reduced anxiety in GF animals is also normalised following restoration of the intestinal microbiota. These results demonstrate that CNS neurotransmission can be profoundly disturbed by the absence of a normal gut microbiota and that this aberrant neurochemical, but not behavioural, profile is resistant to restoration of a normal gut flora in later life.

The microbiome-gut-brain axis during early life regulates the hippocampal serotonergic system in a sex-dependent manner

The aryl hydrocarbon receptor (AHR) has been known to cause immunosuppression after binding dioxin. It has recently been discovered that the receptor may be central to T cell differentiation into FoxP3 + regulatory T cells (Tregs) versus Th17 cells. In this paper, we demonstrate that kynurenine, the first breakdown product in the IDO-dependent tryptophan degradation pathway, activates the AHR. We furthermore show that this activation leads to AHR-dependent Treg generation. We additionally investigate the dependence of TGF-β on the AHR for optimal Treg generation, which may be secondary to the upregulation of this receptor that is seen in T cells postexposure to TGF-β. These results shed light on the relationship of IDO to the generation of Tregs, in addition to highlighting the central importance of the AHR in T cell differentiation. All tissues and cells were derived from mice.

An Interaction between Kynurenine and the Aryl Hydrocarbon Receptor Can Generate Regulatory T Cells

Moderate hyperhomocysteinemia is associated with an increased risk of atherosclerosis, thrombosis and neurodegenerative diseases. Homocysteine accumulation in the blood can be due to many underlying causes, which may interact with each other, e.g. genetic disposition and B-vitamin status. The role of the sulfur-containing amino acid homocysteine in the pathogenesis of diseases remains unclear, even if many studies suggest a causal relationship between homocysteine-mediated processes like oxidative stress, NO-inactivation and endothelial deficiency and atherogenesis. Proposed mechanisms of action of homocysteine are discussed, and the question is addressed, whether effects that are attributed to homocysteine, are not rather the consequence of folate and vitamin B12-deficiency. Deficiency of these Bvitamins in parallel with moderate hyperhomocysteinemia is often found in patients with enhanced activation of the cellular immune system, like Alzheimer´s disease, rheumatoid arthritis and also vascular diseases. In patients with these diseases an association between homocysteine metabolism, oxidative stress and immune activation exists. On the one hand proliferation of immunocompetent cells having an enhanced demand for B-vitamins leads to the accumulation of homocysteine. On the other hand macrophages stimulated by TH1-type cytokine interferon-γ form reactive oxygen species (ROS), which oxidize antioxidants, lipoproteins and oxidation-sensitive B-vitamins. Thereby Th1-type immune response could contribute importantly to the development of hyperhomocysteinemia, and may also be a major determinant of disease progression.

Moderate hyperhomocysteinemia and immune activation.

Rapid measurement of total plasma homocysteine by HPLC

Acetylsalicylic acid (aspirin) is one of the most widely used drugs worldwide, due mainly to its broad therapeutic spectrum with anti-inflammatory, antipyretic, antithrombotic and analgesic effects. However, the exact mechanisms by which aspirin influences inflammation, pain and immune system activation are only partly understood. Within activation of the cellular immune system, Th1-type cytokine interferon (IFN)-gamma induces enzyme indoleamine-2,3-dioxygenase (IDO) which converts tryptophan to kynurenine. In parallel, IFN-gamma induces enzyme GTP-cyclohydrolase I, which gives rise to neopterin production by activated human macrophages. Similarly, tryptophan degradation and neopterin formation increase during several disease states involving Th1-type immune activation. Using stimulated human peripheral blood mononuclear cells (PBMC), the effect of aspirin on tryptophan degradation and neopterin production was investigated. Stimulation of PBMC with mitogens concanavalin A, phytohaemagglutinin and pokeweed mitogen induced significant tryptophan catabolism as was reflected by a decline in tryptophan levels and a parallel increase in kynurenine concentrations compared with unstimulated cells. In parallel, neopterin production was enhanced. Treatment of stimulated PBMC with increasing doses of 1-5 mM aspirin significantly decreased stimulation-induced tryptophan degradation and neopterin production as well. All the effects of aspirin were dose-dependent. The parallel influence of aspirin on both biochemical pathways implies that there was no direct inhibitory effect of aspirin on IDO; rather, it inhibits production of IFN-gamma in mitogen-treated PBMC. The influence of aspirin on biochemical pathways induced by IFN-gamma may represent an important part of its broad pharmacological effect.

Aspirin down‐regulates tryptophan degradation in stimulated human peripheral blood mononuclear cells in vitro

Intake of fruits and vegetables rich in antioxidants is suggested to reduce the incidence of cancer and coronary heart disease in humans. Exceptional antioxidant activity of beet root extracts has been reported. Likewise in animal models, e.g., extracts of red beetroot Beta vulgaris var. rubra revealed significant tumor inhibitory effects. Red beetroot concentrate is universally permitted as a food ingredient. In this study, effects of a commercially available beetroot juice on freshly isolated human peripheral blood mononuclear cells stimulated with the mitogens phytohaemagglutinin and concanavalin A were investigated in vitro. Tryptophan degradation and neopterin formation were monitored in culture supernatants to determine effects of test substances on immunobiochemical pathways which both are induced by the pro-inflammatory cytokine interferon-γ. Compared to unstimulated cells, the mitogens induced significant formation of neopterin and degradation of tryptophan which is reflected by increasing concentrations of kynurenine together with diminished tryptophan levels in supernatants. Addition of beetroot extracts significantly suppressed these mitogen-induced changes, e.g. the rate of neopterin production as well as tryptophan degradation was dose-dependently suppressed. Our data show that beetroot extract is able to counteract pro-inflammatory cascades in peripheral blood mononuclear cells. Because inflammation is strongly involved in the development and progression of several clinical conditions including coronary heart disease and cancer, beneficial effect of beetroot extract may relate to this anti-inflammatory capacity.

/pdf/in-vitro-effects-of-beet-root-juice-on-stimulated-and-57o0h2qa84.pdf

In vitro Effects of Beet Root Juice on Stimulated and Unstimulated Peripheral Blood Mononuclear Cells

STUDY QUESTION How do live birth rates (LBRs), following fresh and vitrified/warmed embryo transfer, compare according to morphological grade, developmental stage and culturing strategy of human blastocysts in vitro? SUMMARY ANSWER Equivalent LBRs were obtained after fresh embryo transfer and after vitrified/warmed embryo transfer of blastocysts of top or non-top quality, while vitrification after prolonged embryo culture of blastocysts with delayed development had a positive impact on LBR. WHAT IS KNOWN ALREADY Blastocyst morphology correlates with clinical outcome; however, few data are available on vitrified/warmed embryo transfer using non-top quality blastocysts. The aim of this study was to determine clinical outcomes of non-top quality blastocysts and blastocysts with delayed development that underwent vitrified/warmed embryo transfer. STUDY DESIGN, SIZE, DURATION This retrospective, single-centre study (conducted January 2009 to June 2013) compared 1010 fresh embryo transfer and 1270 vitrified/warmed embryo transfer of blastocysts originating from the same stimulation cycle. Furthermore, 636 fresh embryo transfers and 304 vitrified/warmed embryo transfer after delayed expansion or blastulation in the same period were also analysed. PARTICIPANTS/MATERIALS, SETTING, METHODS Clinical outcomes after fresh and vitrified/warmed embryo transfer according to blastocyst morphology were compared in both groups. MAIN RESULTS AND THE ROLE OF CHANCE Similar LBRs after fresh embryo transfer or after vitrified/warmed embryo transfer of top or non-top quality blastocysts were observed. A statistically significant improvement in clinical outcomes was obtained after vitrified/warmed embryo transfer of Day 5 embryos with delayed expansion or blastulation when applying prolonged culture. Our study suggests that vitrification of non-top quality blastocysts as well as delayed cavitating and blastulating Day 5 embryos should be considered in autologous IVF cycles. LIMITATIONS AND REASONS FOR CAUTION Given that the present retrospective study used aseptic vitrification of blastocysts, the results, particularly the survival rates, may not be fully applicable to other vitrification protocols. The retrospective nature of the study has to be mentioned. WIDER IMPLICATIONS OF THE FINDINGS Restriction of vitrification to top quality blastocysts may result in discarding potentially viable embryos. STUDY FUNDING AND COMPETING INTERESTS This study was not externally funded. There are no conflicts of interest to declare.

Pregnancy and birth outcomes following fresh or vitrified embryo transfer according to blastocyst morphology and expansion stage, and culturing strategy for delayed development

Barbara Wirleitner

Papers

Moderate hyperhomocysteinemia and immune activation.

Rapid measurement of total plasma homocysteine by HPLC

Aspirin down‐regulates tryptophan degradation in stimulated human peripheral blood mononuclear cells in vitro

In vitro Effects of Beet Root Juice on Stimulated and Unstimulated Peripheral Blood Mononuclear Cells

Pregnancy and birth outcomes following fresh or vitrified embryo transfer according to blastocyst morphology and expansion stage, and culturing strategy for delayed development