The association between neuropsychiatric effects of substance use and occurrence of endoplasmic reticulum and unfolded protein response: A systematic review

INTRODUCTION

This systematic review aimed to assess the association between neuropsychiatric effects of substance use and occurrence of ER stress and unfolded protein response (UPR) through comprehensive electronic search of existing literature and review of their findings.

METHODS

A comprehensive electronic literature search was carried out on research articles published between 1950 to July 2023 through major databases, such as Scopus, Web of Science, Google Scholar, PubMed, PsycINFO, EMBASE, Medline and Cochrane Library.

RESULTS

A total of 21 research articles were selected for review, which were comprised of sixteen animal studies, four human studies and one study on postmortem human brain samples. The selected studies revealed that alcohol, methamphetamine, cocaine, opioid and kratom exposures contributed to neuropsychiatric effects: such as decline in learning and memory function, executive dysfunction, alcohol, methamphetamine, opioid, and kratom dependence. These effects were associated with activation and persistent of ER stress and UPR with elevation of BiP and CHOP expression and the direction of ER stress is progressing towards the PERK-eIF2α-ATF4-CHOP pathway and neuronal apoptosis and neurodegeneration at various regions of the brain. In addition, regular kratom use in humans also contributed to elevation of p-JNK expression, denoting progress of ER stress towards the IRE1-ASK1-JNK-p-JNK pathway which was linked to kratom use disorder. However, treatment with certain compounds or biological agents could reverse the activation of ER stress.

CONCLUSIONS

The neuropsychiatric effects of alcohol, methamphetamine, cocaine, opioid and kratom use may be associated with persistent ER stress and UPR.

Repurposing of antiviral drugs for COVID-19 and impact of repurposed drugs on the nervous system

The recent pandemic, Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has devastated humanity and is continuing to threaten us. Due to the high transmissibility of this pathogen, researchers are still trying to cope with the treatment and prevention of this disease. Few of them were successful in finding cure for COVID-19 by including repurposed drugs in the treatment. In such pandemic situations, when it is nearly impossible to design and implement a new drug target, previously designed antiviral drugs could help against novel viruses, referred to as drug repurposing/redirecting/repositioning or re-profiling. This review describes the current landscape of the repurposing of antiviral drugs for COVID-19 and the impact of these drugs on our nervous system. In some cases, specific antiviral therapy has been notably associated with neurological toxicity, characterized by peripheral neuropathy, neurocognitive and neuropsychiatric effects within the central nervous system (CNS).

Pyridoxine supplementation for levetiracetam-related neuropsychiatric adverse events: A systematic review

OBJECTIVE

Among people with epilepsy, levetiracetam (LEV) can cause neuropsychiatric adverse events (NPAEs) that impact negatively on quality of life. It has been suggested that pyridoxine can ameliorate LEV-related NPAEs. We conducted a systematic review of studies on the use of pyridoxine supplementation to relieve NPAEs associated with LEV therapy.

METHODS

The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, EMBASE, Scholar, Cochrane-CENTRAL (2000-2019), and EThOS platform were searched for studies on the use of pyridoxine in patients with LEV-related NPAEs. Proportions of patients reported to benefit from pyridoxine supplementation were tabulated, and a random-effect model meta-analysis was conducted.

RESULTS

Eleven retrospective studies/case reports and one randomized prospective study, mostly including pediatric populations, were identified. Retrospective studies, which were rated as low quality due to failure to control for bias, reported an overall improvement of NPAEs after pyridoxine supplementation in 72.5% (108/149) of patients. The proportion of patients showing improvement in a pooled analysis of the four largest retrospective studies (n = 134) was 72.1% (95% confidence interval (CI) 47.1-88.3), although there was high heterogeneity across studies (I² = 82%, p_{heterogeneity} < 0.01). In the only prospective trial, patients randomized to pyridoxine supplementation were more likely to show relief from NPAEs than patients not receiving supplementation (p < 0.01), but outcomes might have been affected by assessment bias.

CONCLUSION

This systematic review suggests that pyridoxine might be of benefit in relieving LEV-related NPAEs. However, the quality of the evidence is poor, and better-designed prospective studies that include quantitative as well as qualitative data are needed to define the role of pyridoxine in the management of LEV-related NPAEs.