Differences in Extracellular NAD(+) and NMN Metabolism on the Surface of Vascular Endothelial Cells

Differences in Extracellular NAD(+) and NMN Metabolism on the Surface of Vascular Endothelial Cells

Article Summary:

Exploring the Metabolism of NAD+ and NMN in Vascular Endothelial Cells


  • Nicotinamide adenine dinucleotide (NAD+) is vital for cellular processes and signaling.
  • Proper NAD+ metabolism is crucial for cellular energy turnover.
  • Abnormal NAD+ and NMN metabolism can cause cell aging and cardiovascular diseases.
  • Metabolism of NAD+ and NMN in vascular endothelium differs between species and locations.
  • Understanding these differences is important for modulating the NAD+ system and comparing research results.

Key Cellular Processes and Signaling:

  • NAD+ is involved in redox reactions and serves as a substrate in signaling processes.
  • Enzymes like sirtuins and PARPs are responsible for NAD+ catabolism.
  • NAD+-dependent signaling pathways impact cell cycle progression, transcriptional regulation, and DNA repair.
  • Imbalances in NAD+ synthesis and degradation can lead to pathologies.

Extracellular NAD+ and NMN Metabolism:

  • Precursor recycling is the main approach to regulate NAD+ levels.
  • Extracellular enzymes like CD38 and CD73 are important for NAD+ and NMN cleavage.
  • Endothelial cells play a role in secretion, chemical transport, and blood regulation.
  • Dysfunctional endothelium is linked to various vascular diseases.
  • Targeting ectonucleotidases as therapeutic strategies can treat vascular diseases.

Materials and Methods:

  • Various reagents and cell culture mediums were used for the study.
  • Ethical guidelines and approvals were followed for experiments on mice.
  • Different endothelial cell types were tested, and NAD+ and NMN-degrading activities were determined using HPLC.
  • Immunofluorescence analysis and specific inhibitors were used to identify the enzymes involved.
  • Statistical analysis was conducted using t-tests and ANOVA.

Metabolism of NAD+ and NMN in Endothelial Cells:

  • Endothelial cells exhibit different NAD+ and NMN metabolism, indicating enzyme-substrate affinities.
  • CD73 and CD38 are the main enzymes responsible for NAD+ and NMN hydrolysis.
  • CD73 knockout reduces NMN consumption, implicating its involvement in NMN metabolism.
  • Differences in enzyme affinity for NAD+ and NMN substrates were observed.

Implications and Limitations:

  • NAD+ and NMN impact various functions like inflammation and calcium signaling.
  • Enhancement therapies for NAD+ show systemic benefits.
  • CD38 and CD73 play roles in calcium regulation, inflammation, and vasoprotection.
  • Measurements and cultural conditions affect NAD+ and NMN metabolism in endothelial cells.
  • Standardization and consistent research are crucial in this area.


  • The study examined NAD+ and NMN metabolism in different vascular endothelial cells.
  • CD38 and CD73 were identified as the main enzymes involved in their hydrolysis.
  • Differences in NAD+ and NMN metabolism highlight the need for standardized research.
  • Extracellular NAD+ and NMN metabolism influences various cellular functions and diseases.

Title of paper: Differences in Extracellular NAD(+) and NMN Metabolism on the Surface of Vascular Endothelial Cells

Author(s): Jablonska P, Mierzejewska P, Tomczyk M, Koszalka P, Franczak M, Kawecka A, Kutryb-Zajac B, Braczko A, Smolenski RT, Slominska EM.

Year published: 2022

Published in: Biology (Basel)

Original article can be found here.

Back to blog

Looking For A 99% Pure NMN Supplement?

Reversal NMN is tested and verified by a third party lab. Trusted by many. Delivered worldwide via DHL Express.

Frequently Asked Questions (FAQ'S)