Targeting Zika Virus with New Brain- and Placenta-Crossing Peptide-Porphyrin Conjugates

Area of Science:

• Virology
• Neuroscience
• Drug Discovery

Background:

• Viral outbreaks like Zika virus (ZIKV) pose significant global health threats, particularly during pregnancy, causing severe fetal abnormalities.
• Current treatments for ZIKV are limited by the inability of antiviral drugs to cross the blood-placental and blood-brain barriers (BPB and BBB).
• Existing research has identified peptide-based molecules as potential carriers (BBB peptide shuttles) to deliver therapeutics across the BBB.

Purpose of the Study:

• To develop novel brain-directed, low-toxicity peptide-porphyrin conjugates (PPCs) for targeting ZIKV.
• To evaluate the efficacy and safety of these PPCs in crossing the BPB and BBB.
• To address the unmet need for effective ZIKV treatments.

Main Methods:

• Design and synthesis of several peptide-porphyrin conjugates (PPCs).
• Assessment of PPCs' ability to cross the blood-placental and blood-brain barriers.
• Evaluation of ZIKV targeting efficacy (IC50) and serum stability (t1/2) of promising PPCs.
• Cell viability assays to determine PPC toxicity.

Main Results:

• Several brain-directed PPCs were identified with low toxicity.
• One conjugate, PP-P1, demonstrated effective crossing of both BPB and BBB.
• PP-P1 showed significant efficacy against ZIKV with an IC50 of 1.08 µM.
• PP-P1 exhibited high serum stability (t1/2 ≈ 22 hours) and no observed toxicity at tested concentrations.

Conclusions:

• Peptide-porphyrin conjugation is a viable strategy for developing ZIKV therapeutics.
• The conjugate PP-P1 shows potential as a drug lead for ZIKV infection, effectively crossing critical biological barriers.
• This approach offers a promising solution to overcome drug delivery challenges in treating ZIKV and potentially other viral diseases.