Buranee Kanchanatawan

Immuno-inflammatory, oxidative and nitrosative stress, and neuroprogressive pathways in the etiology, course and treatment of schizophrenia

In recent decades, a significant role for altered immunoinflammatory, oxidative and nitrosative stress (IO&NS) pathways in schizophrenia has been recognized (Smith and Maes, 1995; Wood et al., 2009). Importantly, such processes have provided crucial clues to the etiology, course and management of this devastating disorder. This is the focus of this special edition. Epidemiological findings supporting a role for prenatal viral, bacterial and protozoan infections in the etiology of schizophrenia have provided a seminal contribution to the neurodevelopmental hypothesis of schizophrenia (Brown and Derkits, 2010). The early developmental etiology of schizophrenia to a lesser extent has been focused on decreased vitamin D in early development, including via vitamin D modulation of the immune response to infection (McGrath et al., 2003). Interactions between these factors is suggested by the fact that vitaminDhas a documented role in immunemodulation, especially during placental development and in early childhood (Battersby et al., 2012; Liu et al., 2011). The maximal risk period for maternal infection association with offspring schizophrenia is shown to be early pregnancy (Brown et al., 2004; Khandaker et al., 2012). Interestingly many schizophrenia susceptibility genes are regulated by hypoxia, suggesting close interactions among IO&NS genes and obstetric complications leading to enhanced risk of schizophrenia (Nicodemus et al., 2008; Schmidt-Kastner et al., 2006). Other conditions of pregnancy, including hypoxia associated preeclampsia (Kendell et al., 1996), also increase the risk of the offspring being classed as having schizophrenia, emphasizing the profound impact of prenatal events. The evidence for the role of prenatal infection, both epidemiological and experimental, is excellently reviewed byUrsMeyer (2013–this issue) who has published extensively in this area. Many of the developmental effects of infection are driven not only by O&NS and proinflammatory cytokine increases in the placenta and fetus, but also by associated hypoferremia and zinc deficiency (Ganz and Nemeth, 2009; Prasad, 2009). Such changes render the offspring prone to subsequent second hits over the course of post-natal development, contributing to both the emergence and progression of disease manifestations. This is an important area of experimental research given that the elimination of the effects of maternal infection is estimated to decrease the incidence of schizophrenia by as much as 46% (Brown and Derkits, 2010).

Adjunctive minocycline treatment for major depressive disorder: A proof of concept trial

Objective: Conventional antidepressant treatments result in symptom remission in 30% of those treated for major depressive disorder, raising the need for effective adjunctive therapies. Inflammation has an established role in the pathophysiology of major depressive disorder, and minocycline has been shown to modify the immune-inflammatory processes and also reduce oxidative stress and promote neuronal growth. This double-blind, randomised, placebo-controlled trial examined adjunctive minocycline (200 mg/day, in addition to treatment as usual) for major depressive disorder. This double-blind, randomised, placebo-controlled trial investigated 200 mg/day adjunctive minocycline (in addition to treatment as usual) for major depressive disorder. Methods: A total of 71 adults with major depressive disorder (Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition) were randomised to this 12-week trial. Outcome measures included the Montgomery–Asberg Depression Rating Scale (primary outcome), Clinical Global Impression–Improvement and Clinical Global Impression–Severity, Hamilton Anxiety Rating Scale, Quality of Life Enjoyment and Satisfaction Questionnaire, Social and Occupational Functioning Scale and the Range of Impaired Functioning Tool. The study was registered on the Australian and New Zealand Clinical Trials Register: www.anzctr.org.au, #ACTRN12612000283875. Results: Based on mixed-methods repeated measures analysis of variance at week 12, there was no significant difference in Montgomery–Asberg Depression Rating Scale scores between groups. However, there were significant differences, favouring the minocycline group at week 12 for Clinical Global Impression–Improvement score – effect size (95% confidence interval) = −0.62 [−1.8, −0.3], p = 0.02; Quality of Life Enjoyment and Satisfaction Questionnaire score – effect size (confidence interval) = −0.12 [0.0, 0.2], p < 0.001; and Social and Occupational Functioning Scale and the Range of Impaired Functioning Tool score – 0.79 [−4.5, −1.4], p < 0.001. These effects remained at follow-up (week 16), and Patient Global Impression also became significant, effect size (confidence interval) = 0.57 [−1.7, −0.4], p = 0.017. Conclusion: While the primary outcome was not significant, the improvements in other comprehensive clinical measures suggest that minocycline may be a useful adjunct to improve global experience, functioning and quality of life in people with major depressive disorder. Further studies are warranted to confirm the potential of this accessible agent to optimise treatment outcomes.

IgA/IgM responses to tryptophan and tryptophan catabolites (TRYCATs) are differently associated with prenatal depression, physio-somatic symptoms at the end of term and premenstrual syndrome.

There is some evidence that lowered tryptophan and an activated tryptophan catabolite (TRYCAT) pathway play a role in depression, somatoform disorder, and postpartum blues. The aim of this study is to delineate the associations between the TRYCAT pathway and premenstrual syndrome (PMS) and perinatal depressive and physio-somatic symptoms. We examine the associations between end of term serum IgM and IgA responses to tryptophan and 9 TRYCATs in relation to zinc, C-reactive protein (CRP), and haptoglobin and prenatal physio-somatic (previously known as psychosomatic) symptoms (fatigue, back pain, muscle pain, dyspepsia, obstipation) and prenatal and postnatal depression and anxiety symptoms as measured using the Edinburgh Postnatal Depression Scale (EPDS), Hamilton Depression Rating Scale (HAMD), and Spielberger’s State Anxiety Inventory (STAI). We included pregnant females with (n = 24) and without depression (n = 25) and 24 non-pregnant females. There were no significant associations between the IgA/IgM responses to tryptophan and TRYCATs and prenatal and postnatal depression/anxiety symptoms, except for lowered IgA responses to anthranilic acid in prenatal depression. A large part of the variance in IgA responses to most TRYCATs was explained by PMS and haptoglobin (positively) and CRP (inversely) levels. The IgA responses to TRYCATs were significantly increased in PMS, in particular picolinic, anthranilic, xanthurenic and kynurenic acid, and 3OH-kynurenine. Variance (62.5%) in physio-somatic symptoms at the end of term was explained by PMS, previous depressions, zinc (inversely), CRP and haptoglobin (both positively), and the IgM responses to quinolinic acid (positively), anthranilic acid, and tryptophan (both negatively). The results suggest that mucosa-derived TRYCAT pathway activation is significantly associated with PMS, but not with perinatal depression/anxiety symptoms. Physio-somatic symptoms in pregnancy have an immune-inflammatory pathophysiology. Induction of the TRYCAT pathway appears to be more related to physio-somatic than to depression symptoms.

Deficit Schizophrenia Is Characterized by Defects in IgM-Mediated Responses to Tryptophan Catabolites (TRYCATs): a Paradigm Shift Towards Defects in Natural Self-Regulatory Immune Responses Coupled with Mucosa-Derived TRYCAT Pathway Activation

Deficit schizophrenia is accompanied by mucosa-associated activation of the tryptophan catabolite (TRYCAT) pathway, as indicated by increased IgA responses to noxious (NOX) TRYCATs, but not regulatory or protective (PRO) TRYCATs, suggesting increased neurotoxic, excitotoxic, inflammatory, and oxidative potential. No previous studies examined IgM-mediated autoimmune responses to the TRYCAT pathway in deficit versus nondeficit schizophrenia. We measured IgM responses to NOX TRYCATs, namely, quinolinic acid (QA), 3-OH-kynurenine (3HK), picolinic acid (PA), and xanthurenic (XA) acid, and PRO TRYCATs, including kynurenic acid (KA) and anthranilic acid (AA), in 40 healthy controls and 40 deficit and 40 nondeficit schizophrenic patients. We computed the IgM responses to NOX (QA + PA + 3HK + XA)/PRO (AA + KA) ratio and ∆ differences in IgA − IgM TRYCAT values and NOX/PRO ratio. Deficit schizophrenia is characterized by significantly attenuated IgM responses to all TRYCATs and NOX/PRO ratio and highly increased ∆IgA − IgM NOX/PRO ratio as compared to nondeficit schizophrenia and healthy controls. The negative symptoms of schizophrenia are significantly and positively associated with increased IgM responses directed against the KA/3HK ratio and ∆IgA − IgM NOX/PRO ratio. The findings support the view that deficit schizophrenia is a distinct subtype of schizophrenia that may be significantly discriminated from nondeficit schizophrenia. Deficit schizophrenia is accompanied by a highly specific defect in IgM isotype-mediated regulatory responses directed to the TRYCAT pathway. Lowered IgM regulatory responses together with mucosa-derived activation of the TRYCAT pathway may contribute to neuroprogression, negative symptoms, and deficit schizophrenia. All in all, a highly specific defect in the compensatory (anti-)inflammatory reflex system (CIRS), namely, natural IgM-mediated regulatory responses, may underpin deficit schizophrenia.

Lower Serum Zinc and Higher CRP Strongly Predict Prenatal Depression and Physio-somatic Symptoms, Which All Together Predict Postnatal Depressive Symptoms

Pregnancy and delivery are associated with activation of immune-inflammatory pathways which may prime parturients to develop postnatal depression. There are, however, few data on the associations between immune-inflammatory pathways and prenatal depression and physio-somatic symptoms. This study examined the associations between serum zinc, C-reactive protein (CRP), and haptoglobin at the end of term and prenatal physio-somatic symptoms (fatigue, back pain, muscle pain, dyspepsia, obstipation) and prenatal and postnatal depressive and anxiety symptoms as measured using the Edinburgh Postnatal Depression Scale (EPDS), Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HAMD), and Spielberger’s State Anxiety Inventory (STAI). Zinc and haptoglobin were significantly lower and CRP increased at the end of term as compared with non-pregnant women. Prenatal depression was predicted by lower zinc and lifetime history of depression, anxiety, and premenstrual tension syndrome (PMS). The latter histories were also significantly and inversely related to lower zinc. The severity of prenatal EDPS, HAMD, BDI, STAI, and physio-somatic symptoms was predicted by fatigue in the first and second trimesters, a positive life history of depression, anxiety, and PMS, and lower zinc and higher CRP. Postnatal depressive symptoms are predicted by prenatal depression, physio-somatic symptoms, zinc and CRP. Prenatal depressive and physio-somatic symptoms have an immune-inflammatory pathophysiology, while postnatal depressive symptoms are highly predicted by prenatal immune activation, prenatal depression, and a lifetime history of depression and PMS. Previous episodes of depression, anxiety disorders, and PMS may prime pregnant females to develop prenatal and postnatal depressive symptoms via activated immune pathways.

Activated neuro-oxidative and neuro-nitrosative pathways at the end of term are associated with inflammation and physio-somatic and depression symptoms, while predicting outcome characteristics in mother and baby

OBJECTIVES To examine oxidative & nitrosative stress (O&NS) biomarkers at the end of term in relation to perinatal affective symptoms, neuro-immune biomarkers and pregnancy-related outcome variables. METHODS We measured plasma advanced oxidation protein products (AOPP), nitric oxide metabolites (NOx), total radical trapping antioxidant parameter (TRAP), -sulfhydryl (-SH), peroxides (LOOH) and paraoxonase (PON)1 activity in pregnant women with and without prenatal depression and non-pregnant controls. RESULTS Pregnancy is accompanied by significantly increased AOPP and NOx, and lowered TRAP, -SH and LOOH. Increased O&NS and lowered LOOH and -SH levels are associated with prenatal depressive and physio-somatic symptoms (fatigue, pain, dyspepsia, gastro-intestinal symptoms). Increased AOPP and NOx are significantly associated with lowered -SH, TRAP and zinc, and with increased haptoglobin and C-reactive protein levels. Increased O&NS and lowered TRAP and PON 1 activity, at the end of term predict mother (e.g. hyperpigmentation, labor duration, caesarian section, cord length, breast milk flow) and baby (e.g. sleep and feeding problems) outcome characteristics. CONCLUSIONS Pregnancy is accompanied by interrelated signs of O&NS, lowered antioxidant defenses and activated neuro-immune pathways. Increased O&NS at the end of term is associated with perinatal depressive and physio-somatic symptoms and may predict obstetric and behavioral complications in mother and baby.

IgA/IgM Responses to Gram-Negative Bacteria are not Associated with Perinatal Depression, but with Physio-somatic Symptoms and Activation of the Tryptophan Catabolite Pathway at the End of Term and Postnatal Anxiety

Evidence has implicated the translocation of commensal Gram-negative bacteria (Gram-B) due to leaky gut in the pathophysiology of depression and physio-somatic symptoms (e.g. fatigue, pain, irritable bowel syndrome, malaise, etc.). In addition, the leaky gut may contribute to immune-inflammatory activation and oxidative stress. This study investigated whether bacterial translocation is associated with perinatal depression and anxiety scores and with prenatal physio-somatic symptoms and immune-inflammatory biomarkers, including the tryptophan catabolite (TRYCAT) pathway. Data were collected in pregnant women at the end of term (T1) and 4-6 weeks after delivery (T2) as well as in non-pregnant controls. We examined the associations between serum IgM/IgA responses to Gram-B at the end of term and depression (Edinburgh Postnatal Depression Scale -EPDS) and anxiety (Spielbergers State Anxiety Inventory -STAI) symptoms. Levels of C-reactive protein, zinc, haptoglobin, hematocrit and IgA/IgM responses to 9 TRYCATs were also measured. No significant associations of the IgA/IgM responses to Gram-B with prenatal depression and anxiety were observed. Increased IgA/IgM responses to Gram-B predict higher levels of haptoglobin, hematocrit and TRYCATs, in particular quinolinic acid and the quinolinic acid / kynurenic acid ratio. IgA responses to Gram-B were significantly lowered in pregnant women compared to age-matched non-pregnant women, while IgM responses were significantly elevated in participants with alcohol consumption. Physio-somatic symptoms at the end of term were significantly associated with IgM responses to Klebsiella pneumonia. Postnatal anxiety was significantly predicted by IgA responses to Pseudomonas aeruginosa. In conclusion, our findings suggest that pregnancy may protect against bacterial translocation, while alcohol use may increase bacterial translocation. The results suggest that end of term mucosa-derived immune responses to Gram-B contribute to immune activation, physio-somatic symptoms at the end of term and postnatal anxiety.

Antenatal depression and hematocrit levels as predictors of postpartum depression and anxiety symptoms

The aim of this study is to delineate the risk factors of antenatal depression and its consequences, including postnatal depression, and to examine whether the hematocrit (Hct) is associated with maternal depression. The Edinburgh Postnatal Depression Scale (EPDS), Spielbergers State Anxiety Inventory (STAI), Kennerley and Gath Maternity Blues Assessment Scale (KGB), Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HAMD) were assessed at the end of term (T1) and 2-3 days (T2) and 4-6 weeks (T3) after delivery in 126 women with and without antenatal depression. The Hct was measured at T1. Antenatal depression was significantly predicted by lifetime depression and premenstrual syndrome and less education. Antenatal depression was not associated with obstetric or neonatal outcomes. Antenatal depression symptoms strongly predict depression and anxiety symptoms at T2 and T3. The EPDS, KGB, STAI and BDI, but not the HAMD, scores, were significantly lower at T3 than before. The incidence of depression significantly decreased from T1 (23.8%) to T2 (7.8%) and T3 (5.3%). T1 Hct values significantly predicted the T3 postnatal EPDS, STAI, KGB and BDI scores. Delivery significantly improves depression and anxiety symptoms. Increased Hct in the third trimester is a biomarker of postpartum depression and anxiety symptoms.

Physio-somatic symptoms in schizophrenia: association with depression, anxiety, neurocognitive deficits and the tryptophan catabolite pathway

To investigate the frequency of physio-somatic symptoms (PS) symptoms in schizophrenia and their relation to positive, negative and affective symptoms; neurocognitive deficits and impairments in the tryptophan catabolite (TRYCAT) pathway. Eighty four patients with schizophrenia and 40 healthy controls were assessed using the 12 item Fibromyalgia and Chronic Fatigue Syndrome Rating scale (FF) and scales for negative and positive symptoms, depression and anxiety. Cognitive functioning was tested using the Cambridge Neuropsychological Test Automated Battery (CANTAB). Other assessments included: immunoglobulin (Ig)A and IgM responses to tryptophan catabolites (TRYCATs), namely quinolinic (QA), 3-OH-kynurenine (3HK), picolinic (PA), xanthurenic (XA) and kynurenic acid (KA) and anthranilic acid (AA). More than 50% of the patients studied had elevated levels of physio-somatic (PS) symptoms, significantly co-occurring with depression and anxiety, but not with negative or positive symptoms. PS symptoms were significantly associated with IgA/IgM responses to TRYCATs, including increased IgA responses to 3 HK, PA and XA, and lowered IgA to QA and AA. Fatigue, muscle pain and tension, autonomic and cognitive symptoms and a flu-like malaise were strongly associated with cognitive impairments in spatial planning and working memory, paired associative learning, visual sustained attention and attention set shifting. PS symptoms in schizophrenia aggregate with depression and anxiety symptoms and may be driven by TRYCAT patterning of IgA/IgM-responses, with IgA indicating mucosal-mediated changes and IgM indicating regulatory functions. As such, the patterning of IgA/IgM responses to TRYCATs may indicate differential TRYCATs regulation of neuronal and glia activity that act to regulate PS signalling in schizophrenia.

Body image dissatisfaction in pregnant and non-pregnant females is strongly predicted by immune activation and mucosa-derived activation of the tryptophan catabolite (TRYCAT) pathway

Abstract Objectives: The aim of the present study is to delineate the associations between body image dissatisfaction in pregnant women and immune-inflammatory biomarkers, i.e., C-reactive protein (CRP), zinc and IgA/IgM responses to tryptophan and tryptophan catabolites (TRYCATs). Methods: We assessed 49 pregnant and 24 non-pregnant females and assessed Body Image Satisfaction (BIS) scores at the end of term (T1), and 2–4 days (T2) and 4–6 weeks (T3) after delivery. Subjects were divided in those with a lowered BIS score (≤ 3) versus those with a higher score. Results: Logistic regression analysis showed that a lowered T1 BIS score was predicted by CRP levels and IgA responses to tryptophan (negative) and TRYCATs (positive), perinatal depression, body mass index (BMI) and age. The sum of quinolinic acid, kynurenine, 3-OH-kynurenine and 3-OH-anthranilic acid (reflecting brain quinolinic acid contents) was the single best predictor. In addition, a large part of the variance in the T1, T2 and T3 BIS scores was explained by IgA responses to tryptophan and TRYCATs, especially quinolinic acid. Conclusions: Body image dissatisfaction is strongly associated with inflammation and mucosa-derived IDO activation independently from depression, pregnancy, BMI and age. IgA responses to peripheral TRYCATs, which determine brain quinolinic acid concentrations, also predict body image dissatisfaction.