Orphan opioid receptor oligonucleotides inhibit HIV-1 expression in human brain cells

Area of Science:

• Neuroscience
• Virology
• Molecular Biology

Background:

• Opioid receptors (OR) play roles in the central nervous system.
• HIV-1 infection can affect brain cells, leading to neurological complications.
• The expression and function of OR in human brain cells, particularly in the context of HIV-1, are not fully understood.

Purpose of the Study:

• To investigate the constitutive expression of orphan opioid receptor (OR) mRNA in human fetal brain cells.
• To determine the effect of OR antisense oligonucleotides on HIV-1 expression in various human brain cell cultures.

Main Methods:

• Quantitative analysis of OR mRNA expression in human fetal microglia, astrocytes, and cerebral cortical neurons.
• Treatment of enriched microglial, mixed glial/neuronal, and chronically infected U1 cell cultures with OR antisense and sense oligonucleotides.
• Assessment of HIV-1 expression levels following oligonucleotide treatment.

Main Results:

• Constitutive expression of OR mRNA was detected in human fetal microglia, astrocytes, and cerebral cortical neurons.
• OR antisense oligonucleotides significantly inhibited acute HIV-1 expression in microglial and mixed glial/neuronal cultures.
• No significant inhibition of HIV-1 expression was observed in chronically infected promonocytic U1 cells.
• The sense oligonucleotide also demonstrated inhibitory effects on HIV-1 expression in brain cell cultures.

Conclusions:

• Human brain cells constitutively express mRNA for orphan opioid receptors.
• Antisense oligonucleotides targeting OR exhibit non-specific inhibition of acute HIV-1 infection in human brain cells.
• Further research is needed to elucidate the specific mechanisms and potential therapeutic applications of OR modulation in HIV-1 neuropathogenesis.