Neurobehavioral effects of interferon therapy

Prodromic Inflammatory-Oxidative Stress in Peritoneal Leukocytes of Triple-Transgenic Mice for Alzheimer's Disease

Inflammatory-oxidative stress is known to be pivotal in the pathobiology of Alzheimer's disease (AD), but the involvement of this stress at the peripheral level in the disease's onset has been scarcely studied. This study investigated the pro-inflammatory profile and oxidative stress parameters in peritoneal leukocytes from female triple-transgenic mice for AD (3xTgAD) and non-transgenic mice (NTg). Peritoneal leukocytes were obtained at 2, 4, 6, 12, and 15 months of age. The concentrations of TNFα, INFγ, IL-1β, IL-2, IL-6, IL-17, and IL-10 released in cultures without stimuli and mitogen concanavalin A and lipopolysaccharide presence were measured. The concentrations of reduced glutathione (GSH), oxidized glutathione (GSSG), lipid peroxidation, and Hsp70 were also analyzed in the peritoneal cells. Our results showed that although there was a lower release of pro-inflammatory cytokines by 3xTgAD mice, this response was uncontrolled and overstimulated, especially at a prodromal stage at 2 months of age. In addition, there were lower concentrations of GSH in leukocytes from 3xTgAD and higher amounts of lipid peroxides at 2 and 4 months, as well as, at 6 months, a lower concentration of Hsp70. In conclusion, 3xTgAD mice show a worse pro-inflammatory response and higher oxidative stress than NTg mice during the prodromal stages, potentially supporting the idea that Alzheimer's disease could be a consequence of peripheral alteration in the leukocyte inflammation-oxidation state.

Spatial enrichment of the type 1 interferon signature in the brain of a neuropsychiatric lupus murine model

Among systemic lupus erythematosus (SLE) patients, neuropsychiatric symptoms are highly prevalent, being observed in up to 80% of adult and 95% of pediatric patients. Type 1 interferons, particularly interferon alpha (IFNα), have been implicated in the pathogenesis of SLE and its associated neuropsychiatric symptoms (NPSLE). However, it remains unclear how type 1 interferon signaling in the central nervous system (CNS) might result in neuropsychiatric sequelae. In this study, we validate an NPSLE mouse model and find an elevated peripheral type 1 interferon signature alongside clinically relevant NPSLE symptoms such as anxiety and fatigue. Unbiased single-nucleus sequencing of the hindbrain and hippocampus revealed that interferon-stimulated genes (ISGs) were among the most highly upregulated genes in both regions and that gene pathways involved in cellular interaction and neuronal development were generally repressed among astrocytes, oligodendrocytes, and neurons. Using image-based spatial transcriptomics, we found that the type 1 interferon signature is enriched as spatially distinct patches within the brain parenchyma of these mice. Our results suggest that type 1 interferon in the CNS may play an important mechanistic role in mediating NPSLE behavioral phenotypes by repressing general cellular communication pathways, and that type 1 interferon signaling modulators are a potential therapeutic option for NPSLE.

Endothelial type I interferon response and brain diseases: identifying STING as a therapeutic target

The endothelium layer lining the inner surface of blood vessels serves relevant physiological functions in all body systems, including the exchanges between blood and extravascular space. However, endothelial cells also participate in innate and adaptive immune response that contribute to the pathophysiology of inflammatory disorders. Type I Interferon (IFN) signaling is an inflammatory response triggered by a variety of pathogens, but it can also be induced by misplaced DNA in the cytosol caused by cell stress or gene mutations. Type I IFN produced by blood leukocytes or by the endothelium itself is well-known to activate the interferon receptor (IFNAR) in endothelial cells. Here, we discuss the induction of type I IFN secretion and signaling in the endothelium, specifically in the brain microvasculature where endothelial cells participate in the tight blood-brain barrier (BBB). This barrier is targeted during neuroinflammatory disorders such as infection, multiple sclerosis, Alzheimer's disease and traumatic brain injury. We focus on type I IFN induction through the cGAS-STING activation pathway in endothelial cells in context of autoinflammatory type I interferonopathies, inflammation and infection. By comparing the pathophysiology of two separate infectious diseases-cerebral malaria induced by Plasmodium infection and COVID-19 caused by SARS-CoV-2 infection-we emphasize the relevance of type I IFN and STING-induced vasculopathy in organ dysfunction. Investigating the role of endothelial cells as active type I IFN producers and responders in disease pathogenesis could lead to new therapeutic targets. Namely, endothelial dysfunction and brain inflammation may be avoided with strategies that target excessive STING activation in endothelial cells.

[WITHDRAWN] Spatial enrichment of the type 1 interferon signature in the brain of a neuropsychiatric lupus murine model

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Macrophage Migration Inhibitory Factor in Major Depressive Disorder: A Multilevel Pilot Study

Macrophage migration inhibitory factor (MIF) is a controversially discussed inflammatory marker in major depressive disorder (MDD). While some studies show an association of high MIF protein levels with depression, animal models have yielded conflicting results. Thus, it remains elusive as to whether MIF plays an anti- or pro-depressive role. Therefore, we aimed to examine the potential of MIF at the genetic, expression and protein levels as a risk factor and biomarker to diagnose, monitor, or predict the course of MDD. Patients with a current major depressive episode (n = 66 with, and n = 63 without, prior medication) and remitted patients (n = 39) were compared with healthy controls (n = 61). Currently depressed patients provided a second blood sample after three weeks of therapy. Depression severity was assessed by self-evaluation and clinician rating scales. We genotyped for three MIF polymorphisms and analyzed peripheral MIF expression and serum levels. The absence of minor allele homozygous individuals in the large group of 96 female patients compared with 10-16% in female controls suggests a protective effect for MDD, which was not observed in the male group. There were no significant group differences of protein and expression levels, however, both showed predictive potential for the course of depression severity in some subgroups. While MIF protein levels, but not MIF expression, decreased during treatment, they were not associated with changes in depression severity. This project is the first to investigate three biological levels of MIF in depression. The data hint toward a genetic effect in women, but do not provide robust evidence for the utility of MIF as a biomarker for the diagnosis or monitoring of MDD. The observed predictive potential requires further analysis, emphasizing future attention to confounding factors such as sex and premedication.

Chemobrain, Olfactory and Lifestyle Assessment in Onco-Geriatrics: Sex-Mediated Differences between Chemotherapy and Immunotherapy

A possible link between chemotherapy and cognitive impairment has been identified. In the literature, this condition is usually called chemobrain and can mostly affect some memory domain but can lead also to other cognitive impairments. Olfaction, which is known to be linked with cognitive domain and the nociception system, can also be affected by chemotherapy. The aim of this study was to investigate the main cognitive and olfactory abilities and the functional and nutritional state of a cohort of chemotherapy and immunotherapy onco-geriatric patients and control geriatrics subjects. Cognitive, olfactory, geriatric and nutritional assessments were performed through the Mini Mental State Examination (MMSE), Sniffin' Sticks Screening 12, G8 test and a questionnaire on the adherence of the Mediterranean diet, respectively. Our findings show a gender effect on the MMSE. Overall results indicate more pronounced impairments both at the cognitive and frailty level regardless of the type of therapy. On the other hand, the Sniffin' Sticks performances highlight a significant decrease in olfactory perception ability of subjects following immunotherapy. Significant correlations between olfactory performance and MMSE and G8 scores were also found, as well as between MMSE and G8 measures.

Neuropsychiatric disorders: An immunological perspective

Neuropsychiatric diseases have traditionally been studied from brain, and mind-centric perspectives. However, mounting epidemiological and clinical evidence shows a strong correlation of neuropsychiatric manifestations with immune system activation, suggesting a likely mechanistic interaction between the immune and nervous systems in mediating neuropsychiatric disease. Indeed, immune mediators such as cytokines, antibodies, and complement proteins have been shown to affect various cellular members of the central nervous system in multitudinous ways, such as by modulating neuronal firing rates, inducing cellular apoptosis, or triggering synaptic pruning. These observations have in turn led to the exciting development of clinical therapies aiming to harness this neuro-immune interaction for the treatment of neuropsychiatric disease and symptoms. Besides the clinic, important theoretical fundamentals can be drawn from the immune system and applied to our understanding of the brain and neuropsychiatric disease. These new frameworks could lead to novel insights in the field and further potentiate the development of future therapies to treat neuropsychiatric disease.

Microglial responses to peripheral type 1 interferon

BACKGROUND

Interferon α (IFNα) is a cytokine whose production is increased endogenously in response to viral infection and in autoimmune diseases such as systemic lupus erythematosus (SLE). An elevated IFNα signature has been associated with clinically observed neuro-behavioural deficits such as mild cognitive impairment, fatigue, depression and psychosis in these diseases. However, the mechanisms underlying these neuropsychiatric symptoms remain largely unknown, and it is as yet unclear how IFNα signalling might influence central nervous system (CNS) function. Aberrant microglia-mediated synaptic pruning and function has recently been implicated in several neurodegenerative and neuropsychiatric diseases, but whether and how IFNα modulates these functions are not well defined.

METHODS

Using a model of peripheral IFNα administration, we investigated gene expression changes due to IFNAR signalling in microglia. Bulk RNA sequencing on sorted microglia from wild type and microglia-specific Ifnar1 conditional knockout mice was performed to evaluate IFNα and IFNAR signalling-dependent changes in gene expression. Furthermore, the effects of IFNα on microglia morphology and synapse engulfment were assessed, via immunohistochemistry and flow cytometry.

RESULTS

We found that IFNα exposure through the periphery induces a unique gene signature in microglia that includes the expected upregulation of multiple interferon-stimulated genes (ISGs), as well as the complement component C4b. We additionally characterized several IFNα-dependent changes in microglial phenotype, including expression of CD45 and CD68, cellular morphology and presynaptic engulfment, that reveal subtle brain region-specific differences. Finally, by specifically knocking down expression of IFNAR1 on microglia, we show that these changes are largely attributable to direct IFNAR signalling on microglia and not from indirect signalling effects through other CNS parenchymal cell types which are capable of IFNα-IFNAR signal transduction.

CONCLUSIONS

Peripheral IFNα induces unique genetic and phenotypic changes in microglia that are largely dependent on direct signalling through microglial IFNAR. The IFNα-induced upregulation of C4b could play important roles in the context of aberrant synaptic pruning in neuropsychiatric disease.

An Overview of the Heterogeneity of Major Depressive Disorder: Current Knowledge and Future Prospective

Major depressive disorder (MDD) is estimated to impose maximum debilitating effects on the society by 2030, with its critical effects on health, functioning, quality of life and concomitant high levels of morbidity and mortality. Yet, the disease is inadequately understood, diagnosed and treated. Moreover, with the recent drastic rise in the pace of life, stress has materialized as one of the most potent environmental factors for depression. In this scenario, it is important to understand the modern pathogenetic hypotheses and mechanisms, and possibly try to shift from the traditional approaches in depression therapy. These include the elaboration of pathophysiological changes in heterogeneous systems such as genetic, epigenetic, serotonergic, noradrenergic, gamma-aminobutyric acid, glutamatergic and endocannabinoid systems, neurotrophic factors, HPA axis, immune system as well as cellular stress mechanisms. These components interact with each other in a complex matrix and further elucidation of their mechanism and cascade pathways are needed. This might aid in the identification of MDD subtypes as well as the development of sophisticated biomarkers. Further, characterization might also aid in developing multitargeted therapies that hold much promise as compared to the conventional monoamine based treatment. New candidate pharmacons, refined psychotherapeutic modalities, advanced neuro-surgical and imaging techniques as well as the implementation of pharmacokinetic, pharmacogenetic prescribing guidelines constitute the emerging expanses of MDD treatment.

Depression and Chronic Liver Diseases: Are There Shared Underlying Mechanisms?

The occurrence of depression is higher in patients with chronic liver disease (CLD) than that in the general population. The mechanism described in previous studies mainly focused on inflammation and stress, which not only exists in CLD, but also emerges in common chronic diseases, leaving the specific mechanism unknown. This review was to summarize the prevalence and risk factors of depression in CLD including chronic hepatitis B, chronic hepatitis, alcoholic liver disease, and non-alcoholic fatty liver disease, and to point out the possible underlying mechanism of this potential link. Clarifying the origins of this common comorbidity (depression and CLD) may provide more information to understand both diseases.

Immune activation and neuroinflammation in alcohol use and HIV infection: evidence for shared mechanisms

BACKGROUND

Emerging research points to innate immune mechanisms in the neuropathological and behavioral consequences of heavy alcohol use. Alcohol use is common among people living with HIV infection (PLWH), a chronic condition that carries its own set of long-term effects on brain and behavior. Notably, neurobiological and cognitive profiles associated with heavy alcohol use and HIV infection share several prominent features. This observation raises questions about interacting biological mechanisms as well as compounded impairment when HIV infection and heavy drinking co-occur.

OBJECTIVE AND METHOD

This narrative overview discusses peer-reviewed research on specific immune mechanisms of alcohol that exhibit apparent potential to compound the neurobiological and psychiatric sequelae of HIV infection. These include microbial translocation, systemic immune activation, blood-brain barrier compromise, microglial activation, and neuroinflammation.

RESULTS

Clinical and preclinical evidence supports overlapping mechanistic actions of HIV and alcohol use on peripheral and neural immune systems. In preclinical studies, innate immune signaling mediates many of the detrimental neurocognitive and behavioral effects of alcohol use. Neuropsychopharmacological research suggests potential for a feed-forward cycle in which heavy drinking induces innate immune signaling, which in turn stimulates subsequent alcohol use behavior.

CONCLUSION

Alcohol-induced immune activation and neuroinflammation are a serious health concern for PLWH. Future research to investigate specific immune effects of alcohol in the context of HIV infection has potential to identify novel targets for therapeutic intervention.

LW-AFC, a new formula derived from Liuwei Dihuang decoction, ameliorates behavioral and pathological deterioration via modulating the neuroendocrine-immune system in PrP-hAβPPswe/PS1ΔE9 transgenic mice

BACKGROUND

Accumulating evidence implicates the neuroendocrine immunomodulation (NIM) network in the physiopathological mechanism of Alzheimer's disease (AD). Notably, we previously revealed that the NIM network is dysregulated in the PrP-hAβPPswe/PS1ΔE9 (APP/PS1) transgenic mouse model of AD.

METHODS

After treatment with a novel Liuwei Dihuang formula (LW-AFC), mice were cognitively evaluated in behavioral experiments. Neuron loss, amyloid-β (Aβ) deposition, and Aβ level were analyzed using Nissl staining, immunofluorescence, and an AlphaLISA assay, respectively. Multiplex bead analysis, a radioimmunoassay, immunochemiluminometry, and an enzyme-linked immunosorbent assay (ELISA) were used to measure cytokine and hormone levels. Lymphocyte subsets were detected using flow cytometry. Data between two groups were compared using a Student's t test. Comparison of the data from multiple groups against one group was performed using a one-way analysis of variance (ANOVA) followed by a Dunnett's post hoc test or a two-way repeated-measures analysis of variance with a Tukey multiple comparisons test.

RESULTS

LW-AFC ameliorated the cognitive impairment observed in APP/PS1 mice, including the impairment of object recognition memory, spatial learning and memory, and active and passive avoidance. In addition, LW-AFC alleviated the neuron loss in the hippocampus, suppressed Aβ deposition in the brain, and reduced the concentration of Aβ1-42 in the hippocampus and plasma of APP/PS1 mice. LW-AFC treatment also significantly decreased the secretion of corticotropin-releasing hormone and gonadotropin-releasing hormone in the hypothalamus, and adrenocorticotropic hormone, luteinizing hormone, and follicle-stimulating hormone in the pituitary. Moreover, LW-AFC increased CD8+CD28+ T cells, and reduced CD4+CD25+Foxp3+ T cells in the spleen lymphocytes, downregulated interleukin (IL)-1β, IL-2, IL-6, IL-23, granulocyte-macrophage colony stimulating factor, and tumor necrosis factor-α and -β, and upregulated IL-4 and granulocyte colony stimulating factor in the plasma of APP/PS1 mice.

CONCLUSIONS

LW-AFC ameliorated the behavioral and pathological deterioration of APP/PS1 transgenic mice via the restoration of the NIM network to a greater extent than either memantine or donepezil, which supports the use of LW-AFC as a potential agent for AD therapy.

Isoflurane in the presence or absence of surgery increases hippocampal cytokines associated with memory deficits and responses to brain injury in rats

Evidence from experimental animal studies convincingly argues for a role of pro-inflammatory cytokines due to surgical trauma in causing postoperative cognitive dysfunction. However, other studies have shown exposure to 2-4h of isoflurane anesthetic without surgical trauma can also impair cognitive function. We aimed to determine cytokine changes over time following isoflurane exposure in the presence and absence of surgery and examine subsequent cognitive function. Male rats were exposed to isoflurane (1.8%, 4h) with or without laparotomy or control conditions and tested in a contextual fear conditioning paradigm 8 days later. On day 9 rats were perfused, serum and hippocampal samples were collected and 24 cytokines were analysed. Groups of rats exposed as above were killed 6 or 48h after isoflurane exposure to examine early cytokine changes. Isoflurane exposure resulted in significantly less freezing in the contextual fear conditioning test (F(2,31)=6.11, P=0.006) and addition of laparotomy caused no further deficits (P>0.05). At 6h post isoflurane exposure an immunosuppressive response was observed in the serum while hippocampal cytokines were largely unchanged. These finding suggest isoflurane alone causes inflammatory changes and cognitive deficits. The addition of a laparotomy had a negligible effect. Early after isoflurane exposure changes in serum and hippocampal cytokines were divergent but by 9 days were aligned. At this time cytokines associated with memory deficits and brain injury processes were significantly elevated in serum and brain.

Serotonin gene polymorphisms and lifetime mood disorders in predicting interferon-induced depression in chronic hepatitis C

BACKGROUND

IFN-induced depression is a suitable model for investigating vulnerability to depression. We aimed at investigating the role of two vulnerability factors, lifetime mood disorder (LMD) and 5-HT-related gene polymorphisms in treated patients with infection by Hepatitis C Virus (HCV).

METHODS

Depressive symptoms of 130 consecutive HCV patients with no current psychopathology were measured during treatment with interferon and ribavirin. At baseline, LMD and 3 genotypes (5-HTTLPR, HTR1A, and TPH2) were also assessed.

RESULTS

Subgroups of 43 patients with LMD, 96 with HTR1A-G allele, and 12 with both LMD and HTR1A-G homozigosity scored significantly higher to depression compared to the remaining patients during antiviral therapy. At the multiple regression analysis, LMD and HTR1A-G, whether separately or combined together, explained a similar amount of 10-22% of depression score variance, after controlling for the associated variables (age and gender).

LIMITATIONS

HCV patients referred to a tertiary care center are not representative of all patients with chronic hepatitis C. Mediating factors, including proinflammatory cytokines and other potentially relevant gene polymorphisms, could not be evaluated. Patients were not stratified by degree of liver inflammation. LMD diagnoses were not cross-checked with medical records and IFN-induced depression was measured with a self-report scale only.

CONCLUSIONS

History of mood disorders and HTR1A G allele variation, the C-1019G polymorphism of the transcriptional control region of the 5-HT1A receptor, independently predicted the incidence of IFN-induced depression in HCV patients, whether separately or jointly considered and although not reciprocally associated.

Impact of Hepatitis C Virus Infection on Cognitive Function in Patients With Covert Hepatic Encephalopathy

BACKGROUND

Liver cirrhosis has a significant impact on patient's quality of life and socioeconomic status and is associated with increased susceptibility to vehicle accidents and falls.

OBJECTIVES

This study was conducted to evaluate cognitive function in patients with cirrhosis.

PATIENTS AND METHODS

All subjects, who underwent transient elastography (TE) between March 2014 and August 2014 in Shariati outpatient clinic, Tehran, Iran, were enrolled in the study. The diagnosis of cirrhosis was made based on clinical and laboratory findings and liver stiffness measurement (LSM) values > 14. Wechsler Memory Scale (WMS) and simple visual reaction time (RT) were the neuropsychiatric tests used to assess cognitive function, in all subjects.

RESULTS

A total of 37 cirrhotic patients and 37 matched controls were included. Patients with cirrhosis had significantly lower mean quotient (MQ) score, compared with controls (91 ± 18.2 vs. 114.6 ± 17.5, P <0.001). All of WMS subscales, except associate learning, showed statistically significant differences between the two groups. Reaction time was more prolonged in patients with cirrhosis, compared with controls. Cognitive function of hepatitis C virus (HCV) patients was significantly impaired, with respect to logical memory, visual reproduction and MQ score, compared to other underlying causes of cirrhosis (P = 0.01, P = 0.04, and P = 0.01, respectively).

CONCLUSIONS

Our results suggested that neuropsychiatric and cognitive problems must be considered in the management of covert hepatic encephalopathy (HE) patients, especially in patients with HCV infection. The WMS and simple visual RT tests are useful methods for the early diagnosis of covert HE.

Brain-derived neurotrophic factor: a bridge between inflammation and neuroplasticity

Cytokines are key regulatory mediators involved in the host response to immunological challenges, but also play a critical role in the communication between the immune and the central nervous system. For this, their expression in both systems is under a tight regulatory control. However, pathological conditions may lead to an overproduction of pro-inflammatory cytokines that may have a detrimental impact on central nervous system. In particular, they may damage neuronal structure and function leading to deficits of neuroplasticity, the ability of nervous system to perceive, respond and adapt to external or internal stimuli. In search of the mechanisms by which pro-inflammatory cytokines may affect this crucial brain capability, we will discuss one of the most interesting hypotheses: the involvement of the neurotrophin brain-derived neurotrophic factor (BDNF), which represents one of the major mediators of neuroplasticity.

Persistent neurocognitive decline in a clinic sample of hepatitis C virus-infected persons receiving interferon and ribavirin treatment

Treatment of hepatitis C virus (HCV) with pegylated interferon and ribavirin (IFN/RBV) can be associated with neuropsychiatric side effects, which may necessitate dose reductions or treatment discontinuation. This study aimed to characterize the time course and predictors of cognitive and affective/mood symptoms after IFN/RBV treatment initiation. Forty individuals enrolled in a longitudinal project underwent comprehensive cognitive, medical, and psychiatric assessment at baseline and 10 weeks, 6 months, 12 months, and 18 months after treatment initiation. Analyses were conducted to determine the prevalence of neurocognitive impairment over time; explicate the relationship between neurocognitive impairment, neuropsychiatric symptoms, and liver disease at each time point; and identify predictors of neurocognitive decline as well as cognitive effects of viral clearance. By 10 weeks after initiating IFN/RBV, the prevalence of neurocognitive impairment rose from 22.5 to 47.4% (p < 0.05). Infection with genotype 1 and premorbid depression were associated with more severe declines (p < 0.05). After 18 months, 42.5% remained neurocognitively impaired, independent of viral clearance, severity of liver disease, and current depressive symptoms. Undetectable viral load was not associated with improvement 18 months after initiating treatment (p > 0.10). Results of the current study indicate that IFN/RBV treatment-emergent neurocognitive declines are significant, prevalent, and may persist long after treatment cessation. Clinicians should monitor cognition throughout the course of treatment for HCV, noting that early declines may indicate individuals at elevated risk for persistent neurocognitive impairment. Longer-term studies are needed to determine whether lasting declines may remit over longer intervals or with newer direct acting agents.

Cognitive assessment of patients with minimal hepatic encephalopathy in Brazil

Minimal hepatic encephalopathy is a syndrome caused by liver cirrhosis and accompanied by a broad spectrum of cognitive symptoms. The objective of the present study was to describe the prevalence of minimal hepatic encephalopathy in cirrhotic patients and to compare their cognitive performance with controls using standardized tests. Patients receiving medication or experiencing comorbidities associated with cognitive disorders were excluded. The final cohort was compared with a control-matched group using the Mini-Mental State Examination (MMSE), as well as Simple Drawing, Clock Drawing, Rey Auditory-Verbal Learning Test (RAVLT), Random Letter, Stroop, Trail-Making Test (TMT) A and B, Boston Naming, Category Verbal Fluency, Digit Span, Constructional Praxis, Processing Speed, and Similarities Tests. The results indicated no differences in the prevalence of cognitive complaints spontaneously reported by 29 patients with cirrhosis versus 22 healthy controls. The most affected tests included: MMSE (26.3 ± 2 vs. 28.1 ± 1.8 points; p = 0.004), learning (35.4 ± 9 vs. 41 ± 9.1 points; p = 0.041), retroactive interference (0.67 ± 0.22 vs. 0.84 ± 0.16 points; p = 0.004), and recognition (8.7 ± 2.6 vs. 11.2 ± 4.1 points; p = 0.024) in RAVLT, TMT-A (63.2 ± 29.3 vs. 47.6 ± 16.5 s; p = 0.029) and TMT-B (197.9 ± 88.1 vs. 146.8 ± 76.5 s; p = 0.03). No differences were observed with respect to age, gender, and education. In conclusion, MMSE proved to be a useful tool for detecting global cognitive impairment experienced by cirrhosis patients. Moreover, the most impaired cognitive functions were verbal episodic memory and information processing speed. These findings suggest that minimal hepatic encephalopathy represents a disorder that affects the medial temporal system and, possibly, the prefrontal cortex, and this requires further study.

Toxoplasma gondii infection and behaviour - location, location, location?

Parasite location has been proposed as an important factor in the behavioural changes observed in rodents infected with the protozoan Toxoplasma gondii. During the chronic stages of infection, encysted parasites are found in the brain but it remains unclear whether the parasite has tropism for specific brain regions. Parasite tissue cysts are found in all brain areas with some, but not all, prior studies reporting higher numbers located in the amygdala and frontal cortex. A stochastic process of parasite location does not, however, seem to explain the distinct and often subtle changes observed in rodent behaviour. One factor that could contribute to the specific changes is increased dopamine production by T. gondii. Recently, it was found that cells encysted with parasites in the brains of experimentally infected rodents have high levels of dopamine and that the parasite encodes a tyrosine hydroxylase, the rate-limiting enzyme in the synthesis of this neurotransmitter. A mechanism is proposed that could explain the behaviour changes due to parasite regulation of dopamine. This could have important implications for T. gondii infections in humans.

Predictors of psychopathological outcome during peg-interferon and ribavirin therapy in patients with chronic HCV-correlated hepatitis

Peg-interferon (Peg-IFN) and ribavirin (RBV) therapy is reported to induce psychiatric symptoms and syndromes in 20% of patients treated for Hepatitis C Virus (HCV) infection. Present study was aimed to quantify the phenomenon and assess the influence of psychiatric counseling over antiviral completion rate and the use of psychometric tools, in terms of prediction of psychopathological outcome. Ninety-six HCV patients were assessed, before antiviral treatment, by means of the Sheehan Disability Scale (SDS), Mood Disorder Questionnaire (MDQ), Symptom Checklist-90, and Internal State Scale (ISS). Sociodemographic and clinical variables and completion rate were collected. Binary logistic regression was performed to evaluate whether scores were predictive of psychiatric visit, development of psychiatric disorders, and need for treatment. Ninety-five patients (99%) completed antiviral treatment; 27 subjects (29%) needed psychiatric visit: among them, mood disorder was diagnosed in 15 (16%) and were pharmacologically treated. Baseline SDS and MDQ higher scores were found to be predictive of psychiatric visit [odds ratio (OR)=1.258, P<0.001 and OR=1.425, P=0.05, respectively]. Furthermore, higher MDQ score (P=0.017) and ISS hostility scores (OR=1.048, P=0.014) at baseline predicted the subsequent development of mood episodes, while ISS activation correlated negatively (OR=0.948, P=0.009). Finally, the need for treatment was predicted by higher scores at the MDQ and ISS activation items (OR=2.467, P=0.030; OR=0.970, P=0.038). Present findings suggest that psychiatric counseling may be needed in almost 30% of HCV patients on antiviral treatment, with positive influence over the completion rate. Baseline higher scores at psychometric questionnaires-MDQ-in particular, predictors of psychopathological outcome during Peg-IFN and RBV therapy in patients with chronic HCV-correlated hepatitis reflecting individual functioning before starting antiviral therapy and positive history for mood disorders, seem to predict psychiatric visit, onset of mood episodes, and need for psychopharmacological treatment. Further investigation is warranted to confirm results.

Dopaminergic mechanisms of reduced basal ganglia responses to hedonic reward during interferon alfa administration

CONTEXT

Inflammatory cytokines or cytokine inducers can alter basal ganglia activity, including reducing responsiveness to rewarding stimuli that may be mediated by cytokine effects on dopamine function.

OBJECTIVES

To determine whether long-term administration of the inflammatory cytokine interferon alfa reduces the basal ganglia response to reward and whether such changes are associated with decreased presynaptic striatal dopamine function and altered behavior.

DESIGN

Cross-sectional and longitudinal studies.

SETTING

Outpatient research unit and neuroimaging facilities at Emory University, Atlanta, Georgia.

PATIENTS

Medically stable adults with chronic hepatitis C virus (HCV) infection eligible for interferon alfa treatment.

MAIN OUTCOME MEASURES

Neural activity in the ventral striatum during a hedonic reward task as measured by functional magnetic resonance imaging, uptake and turnover of radiolabeled fluorodopa F 18 (18F-dopa) in caudate and putamen using positron emission tomography, and interferon alfa-induced depression, anhedonia, fatigue, and neurotoxicity.

RESULTS

Patients with HCV receiving interferon alfa for 4 to 6 weeks (n = 14) exhibited significantly reduced bilateral activation of the ventral striatum in the win vs lose condition of a gambling task compared with patients with HCV awaiting interferon alfa treatment (n = 14). Reduced activation of the ventral striatum was, in turn, significantly correlated with anhedonia, depression, and fatigue. In a separate longitudinal study, patients with HCV treated with interferon alfa for 4 to 6 weeks (n = 12) exhibited significantly increased 18F-dopa uptake and decreased 18F-dopa turnover in caudate and putamen and in the same ventral striatal regions identified in the functional magnetic resonance imaging study. Baseline and percentage change in 18F-dopa uptake and turnover were correlated with behavioral alterations, including depression, fatigue, and neurotoxicity, during interferon alfa administration.

CONCLUSIONS

These data replicate and extend findings that inflammatory stimuli, including inflammatory cytokines, such as interferon alfa, alter basal ganglia activity and behavior in association with significant changes in presynaptic striatal dopamine function consistent with decreased dopamine synthesis or release.

Management of adverse effects of Peg-IFN and ribavirin therapy for hepatitis C

HCV infects approximately 2-3% of the global population and is a leading cause of end-stage liver disease and hepatocellular carcinoma. Treatment of HCV infection with Peg-IFN in combination with ribavirin can eradicate HCV infection in 40-90% of patients; however, a major barrier to treatment uptake and delivery is the association of this therapy with frequent and, at times, serious adverse effects. Recognition and effective management of these adverse effects are critical components of the successful treatment of chronic HCV infection. In clinical trials, approximately 10-15% of patients discontinue Peg-IFN and ribavirin therapy due to adverse effects; however, in clinical practice, the rate of treatment discontinuation has been reported to be substantially higher. The off-target effect of Peg-IFN and ribavirin impacts most, if not all, organ systems; the most common adverse effects are hematologic, dermatologic, neurologic, immunologic, gastrointestinal, pulmonary, cardiovascular, and ocular. Regional and global variability exists in the nature of these adverse effects and the strategies employed to ameliorate their impact. This article provides a comprehensive literature review that systematically describes the adverse effects of Peg-IFN-α and ribavirin on various organ systems and, more importantly, recommends consensus approaches to managing those effects.

Prophylactic antidepressant treatment in patients with hepatitis C on antiviral therapy: a double-blind, placebo-controlled trial

BACKGROUND

Approximately one-third of patients undergoing interferon-α (IFN-α) therapy for treatment of the hepatitis C virus (HCV) develop major depression, which decreases functioning and may lead to the reduction or discontinuation of treatment.

OBJECTIVE

The authors examined the efficacy of citalopram in preventing IFN-α-induced depression in HCV patients.

METHOD

This was a randomized, controlled trial comparing citalopram with placebo in 39 HCV patients.

RESULTS

The rate of IFN-α-induced depression in the sample was 15.4% (6/39). Randomization to citalopram did not decrease the statistical likelihood of developing IFN-α-induced depression (10.5% for citalopram vs. 20.0% for placebo).

CONCLUSION

Citalopram does not prevent depression onset; however, an empirically-supported treatment recommendation for IFN-α-induced depression includes monitoring depressive symptoms throughout antiviral therapy and initiating psychiatric treatment at the initial signs of depression.

Antiinfective agents affecting cognition: a review

The adverse effects of antimicrobial, antiviral and anthelmintic agents on cognitive function have attracted substantial research interest in the last three decades. There are sporadic individual reports of negative effects on cognition by penicillin, amoxycillin, cloxacillin, cephalothin, cephazolin, cefuroxime, ceftazidime, tobramycin, doxycycline, chloramphenicol, lomefloxacin, pefloxacin, isoniazid, amphotericin B, acyclovir, chloroquine, clioquinol, metronidazole, sulfasalazine among other antimicrobial agents. Antimicrobial and antiprotozoal agents reported to affect consciousness in particular are amoxycillin, cloxacillin, ticarcillin, cephalothin, cephazolin, ceftazidime, cefuroxime, tobramycin, lomefloxacin, pefloxacin, amphotericin B, acyclovir, chloroquine, clioquinol, and metronidazole. The relationship between some other antimicrobial, antiviral and anthelmintic agents and cognition is yet to be clearly established due to the existence of controversial reports. Few antimicrobial, antiviral or anthelmintic agents have been found to be devoid of any effect on memory. A few others may enhance cognitive performance. This review focuses on this issue, summarizing the published clinical and experimental studies relevant to this area of research and discussing its clinical implications. Suggested mechanisms responsible for the adverse effects of different antimicrobial, antiviral, and anthelmintic agents on cognitive function are reported. Future recommendations point to immense research opportunities to investigate the cognitive profile of newly discovered antimicrobial agents.

Neuropsychological sequelae of non-central nervous system cancer and cancer therapy

Cancer patients report numerous adverse symptoms associated with their disease and treatment including cognitive dysfunction, fatigue, and affective distress. Cognitive dysfunction is ubiquitous in patients with primary central nervous system (CNS) cancer and recent evidence has documented similar deficits in patients with non-CNS cancer as well. Both the cancer itself and treatments including chemotherapy, biological response modifiers, and hormonal therapies have been demonstrated to adversely impact cognitive and neurobehavioral function. Neuroimaging and neurophysiological investigations have likewise revealed alterations in brain function that are helping to account for the nature of these cognitive disorders. Similarly, preclinical animal research is assisting to identify the pathophysiological mechanisms that underlie treatment-related neurotoxicities. The coalescence of multidisciplinary clinical and research efforts hold promise for the development of interventions that may offer neuroprotection in addition to currently available symptomatic therapies and cognitive rehabilitation techniques.

Differences of peripheral inflammatory markers between mild cognitive impairment and Alzheimer's disease

Multiple pathogenic factors may contribute to the pathophysiology of Alzheimer's disease (AD). Peripheral markers have been used to assess biochemical alterations associated with AD and mild cognitive impairment (MCI) involved in its pathophysiology. The present study was conducted to evaluate inflammatory peripheral markers in elderly patients with MCI, patients with AD and normal elderly subjects. We measured plasma levels of different cytokines (IL-6, TNF-alpha and IFN-alpha) and platelet levels of cyclooxigenase-2 (COX-2) from 34 patients with MCI, 45 patients with AD and 28 age-matched control subjects. MCI and AD patients showed similarities in TNF-alpha and COX-2 levels, and differences in IL-6 and INF-alpha. Whereas augmented IL-6 levels have been found in AD patients, a significant increase in INF-alpha has been detected only in patients with MCI possibly associated with the depression stage frequently found in cognitive impairment. In conclusion, inflammatory response may be an early factor in AD development and these changes in circulating markers are possibly related to the progression of MCI to AD.

Cognitive function after chemotherapy in adults with solid tumours

BACKGROUND

Evidence is emerging that some cancer survivors suffer cognitive impairment after chemotherapy; the cause is unknown.

METHODS

Here we review studies evaluating cognitive impairment in adult cancer survivors and discuss methodological challenges associated with this research. We evaluate evidence for cognitive impairment in cancer patients, the incidence of self-reported impairment, and identify potential mechanisms and confounders.

RESULTS

Most studies of cognitive function are cross-sectional and report impairment in 15-45% of subjects. Longitudinal studies suggest that some impairment is present prior to receiving chemotherapy, and that this worsens in some patients. The aetiology is unknown. A larger number of subjects self-report changes in cognitive function after chemotherapy; this does not correlate with objective testing.

CONCLUSIONS

Cognitive impairment occurs in a subset of cancer survivors and is generally subtle. Most evidence suggests an association with chemotherapy although other factors associated with the diagnosis and treatment of cancer may contribute.

Randomized Trial of an Allogeneic Melanoma Lysate Vaccine With Low-Dose Interferon Alfa-2b Compared With High-Dose Interferon Alfa-2b for Resected Stage III Cutaneous Melanoma

Purpose

To compare the overall survival (OS) of patients with resected stage III melanoma administered active specific immunotherapy and low-dose interferon alfa-2b (IFN-α-2b) with the OS achieved using high-dose IFN-α-2b.

Patients and Methods

An Ad Hoc Melanoma Working Group of 25 investigators treated 604 patients from April 1997 to January 2003. Patients were stratified by sex and number of nodes and were randomly assigned to receive either 2 years of treatment with active specific immunotherapy with allogeneic melanoma lysates and low-dose IFN-α-2b (arm 1) or high-dose IFN-α-2b alone for 1 year (arm 2). Active specific immunotherapy was injected subcutaneously (SC) weekly for 4 weeks, at week 8, and bimonthly thereafter. IFN-α-2b SC was begun on week 4 and continued thrice weekly at 5 MU/m2 for 2 years. IFN-α-2b in arm 2 was administered according to the Eastern Cooperative Oncology Group 1684 study regimen.

Results

Median follow-up time was 32 months for all patients and 42 months for surviving patients. Median OS time exceeds 84 months in arm 1 and is 83 months in arm 2 (P = .56). Five-year OS rate is 61% in arm 1 and 57% in arm 2. Estimated 5-year relapse-free survival (RFS) rate is 50% in arm 1 and 48% in arm 2, with median RFS times of 58 and 50 months, respectively. The incidence of serious adverse events as a result of treatment was the same in both arms, but more severe neuropsychiatric toxicity was seen in arm 2.

Conclusion

OS and RFS achieved by active specific immunotherapy and low-dose IFN-α-2b were indistinguishable from those achieved by high-dose IFN-α-2b. Long RFS and OS times were observed in both treatment arms.

Interferon-α effects are exaggerated when administered on a psychosocial stressor backdrop: Cytokine, corticosterone and brain monoamine variations

Immunotherapy involving interferon-alpha (IFN-alpha) treatment is often accompanied by symptoms of depressive illness. These effects may stem from the direct actions of the cytokine, or may be unique to individuals undergoing considerable strain. In two experiments using CD-1 mice, we demonstrate that intraperitoneal administration of IFN-alpha dose dependently influences plasma corticosterone and sickness behaviors, and modestly influences norepinephrine turnover in brain. However, when mice are exposed to a psychosocial stressor (social disruption by transferring mice from isolated to grouped conditions, and to a moderate extent a transfer from grouped housing to isolation), the effects of IFN-alpha on sickness, plasma corticosterone and hippocampal norepinephrine, as well as on the levels of circulating IL-6, TNF-alpha and IL-10 (but not IL-1beta or IFN-gamma) are greatly augmented. It is suggested that the depressive effects of immunotherapy in humans likewise reflects the synergistic actions of the cytokine and the ongoing distress experienced by patients.

Serotonin-1A receptor gene HTR1A variation predicts interferon-induced depression in chronic hepatitis C

BACKGROUND & AIMS

Interferon-induced depression is a major complication in antiviral therapy of chronic hepatitis C. Little is known about underlying mechanisms and reliable predictive factors associated with cytokine-induced depressive symptoms.

METHODS

In a cohort of 139 hepatitis C-infected outpatients treated with interferon alfa-2b, we investigated the impact of functional gene variants of the cerebral serotonin (5-HT) signalling pathway previously implicated in depression risk. Depression was monitored using the Hospital Anxiety and Depression Scale (HADS). All patients were genotyped for functional variations in the 5-HT(1A) receptor (HTR1A), 5-HT transporter (SLC6A4, 5-HTT), and tryptophan hydoxylase-2 (TPH2).

RESULTS

Homozygosity for the HTR1A-1019G variant significantly increased both incidence and severity of interferon-induced depression. Maximum increases in HADS depression scores during antiviral therapy correlated with HTR1A variation (P = .011). Clinically relevant depression was significantly associated with the HTR1A-1019G genotype (P = .017; OR, 2.95). 5-HTT and TPH2 variations did not contribute significantly to the prediction of interferon-induced depression by HTR1A (sensitivity, 35.9%; specificity, 84.0%).

CONCLUSIONS

Our findings suggest an impact of allelic variation in 5-HT(1A) receptor expression on the development of interferon alfa-induced depression during antiviral treatment of chronic hepatitis C. Prediction models of interferon-induced depressive symptoms based on HTR1A variation offer a perspective for an antidepressant selective serotonin reuptake inhibitor prophylaxis in patients genetically at risk for interferon-induced depression.

Subthreshold mania as predictor of depression during interferon treatment in HCV+ patients without current or lifetime psychiatric disorders

BACKGROUND

Depression is considered the most frequent interferon (IFN)-alpha-induced psychiatric disorder. However, other neuropsychiatric side effects of IFN treatment, such as irritability, anxiety, and manic episodes, are reported as well. We analyzed the impact of lifetime manic-hypomanic symptoms and anxiety on the development of depression in hepatitis-C-virus-infected subjects treated with two different types of IFN-alpha.

METHODS

At baseline, subjects received thorough diagnostic assessment to exclude lifetime or current psychiatric symptoms. During treatment, subjects were administered interviewer-based and self-report instruments.

RESULTS

Six (12%) of 49 individuals with a negative history of psychiatric disorders developed major depression during treatment with IFN. The onset of depression was significantly associated with the presence of lifetime subthreshold manic-hypomanic symptoms. Subjects exceeding manic threshold were more likely to develop depression than those below threshold (33.3% vs. 7.5%, P=.033).

CONCLUSIONS

Our data suggest that individuals treated with IFN with no past history of psychiatric disorders are more likely to develop depression if they experienced subthreshold manic-hypomanic symptoms in their lifetime. These findings derive from an exploratory study and may have important implications for the prevention of IFN-induced depression if replicated in larger studies.

Methodological approaches in the assessment of interferon-alfa-induced depression in patients with chronic hepatitis C - a critical review

In recent years, research on interferon (IFN)-induced depressive symptoms in antivirally treated patients suffering from chronic hepatitis C (CHC) has considerably intensified. Profound scientific knowledge of this complication is of great relevance with regard to adherence, compliance, and premature therapy discontinuation. Presently, there is considerable variability of both, the frequency and extent of IFN-induced depression reported in different cohorts of patients. The aim of the presented study was to systematically review recent literature of research within this field; and particularly (1) to identify to what extent methodological bias contributed to inconsistent results in different studies, (2) to critically appraise methods and results of studies published so far, and (3) to suggest directions for future work, especially with respect to alternative and improved methodological approaches. The results of this critical review suggest that the variability of findings seem to be largely due to different study populations, treatment regimens, methodological approaches, and sometimes arbitrary or at least poorly defined choice of screening instruments for depression, particularly criteria for clinically relevant depression (cut-off criteria). Study designs and methodological approaches to investigate IFN-alfa-induced depression in patients with CHC have been incoherent. Future research in this field needs agreement on the use of standardized assessment of IFN-induced depression in CHC. Furthermore, objective criteria and guidelines for the treatment of IFN-induced depression in these patients are needed in clinical practice.

Methylphenidate for alpha-interferon induced depression

Interferon-Alpha (IFN) has been effective in the treatment of chronic viral infections and cancer albeit the added risk of severe depression. The literature has reported effectiveness in the use of antidepressants for interferon-induced depression. We report a case of severe protracted depression induced by IFN in a patient diagnosed with melanoma who responded rapidly to a course of methylphenidate using the Hamilton Depressive Rating Scale. Methylphenidate appeared to be effective in the treatment of neurovegetative symptoms of major depression induced by IFN. This report provides further clinical evidence that the neurovegetative symptoms of depression might respond better to a norepinephrine uptake inhibitor or psycho-stimulants.