Acute dystonia after injection of pegylated interferon alpha-2b

DYT-PRKRA Mutation P222L Enhances PACT’s Stimulatory Activity on Type I Interferon Induction

DYT-PRKRA (dystonia 16 or DYT-PRKRA) is caused by mutations in the PRKRA gene that encodes PACT, the protein activator of interferon (IFN)-induced double-stranded (ds) RNA-activated protein kinase (PKR). PACT participates in several cellular pathways, of which its role as a PKR activator protein during integrated stress response (ISR) is the best characterized. Previously, we have established that the DYT-PRKRA mutations cause enhanced activation of PKR during ISR to sensitize DYT-PRKRA cells to apoptosis. In this study, we evaluate if the most prevalent substitution mutation reported in DYT-PRKRA patients alters PACT’s functional role in induction of type I IFNs via the retinoic acid-inducible gene I (RIG-I) signaling. Our results indicate that the P222L mutation augments PACT’s ability to induce IFN β in response to dsRNA and the basal expression of IFN β and IFN-stimulated genes (ISGs) is higher in DYT-PRKRA patient cells compared to cells from the unaffected controls. Additionally, IFN β and ISGs are also induced at higher levels in DYT-PRKRA cells in response to dsRNA. These results offer a new avenue for investigations directed towards understanding the underlying molecular pathomechanisms in DYT-PRKRA.

Evidence for association between hepatitis C virus and Parkinson's disease

Parkinson's disease (PD) is a globally prevalent neurodegenerative disorder, characterized by progressive neuronal loss in the substantia nigra and formation of Lewy bodies. These pathological characteristics are clinically translated into motor symptoms, such as bradykinesia, rigidity, resting tremors, and postural instability. Emerging data from epidemiological studies suggest a possible association between PD and hepatitis C virus (HCV) infection, which affects up to 71 million individuals worldwide. Preclinical studies have shown that HCV can penetrate and replicate within the brain macrophages and microglial cells, increasing their production of pro-inflammatory cytokines that can directly cause neuronal toxicity. Other studies reported that interferon, previously used to treat HCV infection, can increase the risk of PD through inhibition of the nigrostriatal dopaminergic transmission or induction of neuroinflammation. In this article, we provide a comprehensive review on the possible association between HCV infection and PD and highlight recommendations for further research and practice in this regard.

Serotonin-1A receptor CC genotype is associated with persistent depression related to interferon-alpha in hepatitis C patients

OBJECTIVE

The aim of this study is to investigate the development of depression during interferon-alpha (IFN-α) therapy and the variations in the expression of the serotonin receptor (5-HTR) and transporter (5-HTT) in hepatitis C patients.

METHOD

Hepatitis C patients (n=277) were given the Mini International Neuropsychiatric Interview at the end of IFN-α therapy. Three polymorphisms were genotyped: the serotonin transporter repeat length polymorphic region [5-HTT gene-linked polymorphic region (5-HTTLPR)], as well as SNPs rs25531 and rs6295, located within the 5-HTTLPR and the transcriptional control region of the 5-HTR1A gene, respectively.

RESULTS

The diagnosis of current depression, which was associated with IFN-α-related depression (P<.001), demonstrated a statistically significant association with the CC genotype of the 5-HTR1A gene (odds ratio=5.57, 95% confidence interval=1.61-19.24, P=.007).

CONCLUSIONS

Persistent depression may represent a more specific type of IFN-α-related psychopathology. Future studies need to investigate the genetic risk factors for vulnerability associated with persistent depression. Limitations, such as the study's cross-sectional design, small sample size and retrospective assessment of IFN-α-induced depression diagnosis, must be taken into account while interpreting the results found in this study.

[Central nervous system complications in patients undergoing cytotoxic chemotherapy and targeted therapies]

Anti-cancer treatments (cytotoxic chemotherapies, targeted therapies and hormonotherapies) are known to induce early and delayed neurological toxicities. Acute encephalopathies and posterior reversible encephalopathies are better known and described, physiopathological hypotheses are emerging. It is difficult to discriminate what drug is causing the symptoms in patients treated with multiple cytotoxic drugs. Methotrexate and ifosfamide are responsible for acute encephalopathies. L-asparaginase and methotrexate or targeted therapies may induce cerebrovascular complications. As life expectancy increases and more complex regimen including innovative targeted therapies are developed, new toxicity profiles can be expected. To be able to provide an early diagnosis, prevention, and treatment (when existing) of these pathologies remains a tremendous challenge that would allow a good quality of life with social and professional life after their cancer is cured.

Incidence of psychiatric side effects during pegylated interferon- alpha retreatment in nonresponder hepatitis C virus-infected patients

OBJECTIVE

Evaluate the incidence of mental disorders using pegylated interferon plus ribavirin retreatment in nonresponder hepatitis C virus-infected patients.

METHOD

The Mini-International Neuropsychiatric Interview (MINI) was used to evaluate 30 hepatitis C virus-infected interferon-nonresponder patients at baseline and following 4, 12 and 24 weeks of pegylated interferon retreatment.

RESULTS

During the pegylated interferon/ribavirin retreatment, 5(16.6%) patients developed psychiatric side effects: 3(10%) were diagnosed with major depressive disorder, 1(3.3%) had a brief psychotic disorder and 1(3.3%) presented with panic attacks.

CONCLUSION

This is the first prospective study evaluating the incidence of neuropsychiatric side effects during interferon retreatment of hepatitis C virus-infected patients, suggesting that the risk of acquiring serious psychiatric symptoms during retreatment with interferon-alpha (IFN-alpha) may not be higher than during the first antiviral therapy. This finding challenges the hypothesis that during a second treatment with IFN-alpha, patients with hepatitis C may be at greater risk for neuropsychiatric side effects than naïve patients.