NAD⁺ modulation with nicotinamide mononucleotide coated 3D printed microneedle implants

Area of Science:

• Biophotonics
• Dermatology
• Biochemistry

Background:

• Nicotinamide adenine dinucleotide (NAD+) deficiency is linked to aging and disease.
• Current methods for measuring NAD+ are invasive and destructive.
• A non-invasive method is needed for studying NAD+ dynamics in vivo.

Purpose of the Study:

• To develop and validate a non-invasive optical technique for measuring NAD+ upregulation.
• To investigate the delivery of nicotinamide mononucleotide (NMN) using microneedle implants.
• To correlate microneedle coating properties with drug delivery efficacy.

Main Methods:

• Utilized multiphoton microscopy to detect intrinsic autofluorescence of NAD(P)H.
• Employed microneedle (μND) implants for topical delivery of NMN.
• Analyzed rheomechanical properties of coating formulations and their effect on drug loading.
• Measured changes in NADH fluorescence lifetime in keratinocytes and ex vivo skin.

Main Results:

• Demonstrated a decrease in NADH fluorescence lifetime with increasing NMN dosage.
• Showed that coating formulation rheology impacts NMN loading on μNDs.
• Observed similar trends in NAD(P)H fluorescence lifetime in ex vivo mouse skin.
• Validated the non-invasive optical technique for monitoring NAD+ precursor delivery.

Conclusions:

• A non-invasive optical method using multiphoton microscopy can monitor NAD+ levels.
• Microneedle implants offer a promising minimally invasive delivery system for NAD+ precursors.
• This approach can improve patient compliance and therapeutic outcomes for age-related conditions.