Synthetic models of the nitrogenase FeMo cofactor.

The FeMo cofactor (FeMoco), the key active site in the Mo-based nitrogenase, is one of the most complicated metalloenzyme molecules. Synthesis of the FeMoco model cluster ([MoFeSC]) is essential to understanding its function in dinitrogen binding, activation, and conversion. However, the complex framework of the FeMoco cluster, which features a unique trigonal prismatic [FeC] moiety comprising a -bridging carbide, has made the synthesis of the cluster a persistent challenge.

Endothelial prostacyclin protects the kidney from ischemia-reperfusion injury.

Prostacyclin, or PGI, is a product of PGI synthase (PGIS), down-stream of cyclooxygenase pathway. PGI has been demonstrated to play an important role in maintaining renal blood flow. Non-steroidal anti-inflammatory drugs (NSAIDs) that inhibit cyclooxygenase are reported to increase the susceptibility of patients to acute kidney injury (AKI).

Nicotinamide Mononucleotide, an NAD Precursor, Rescues Age-Associated Susceptibility to AKI in a Sirtuin 1-Dependent Manner.

The rapid growth of an aging population creates challenges regarding age-related diseases, including AKI, for which both the prevalence and death rate increase with age. The molecular mechanism by which the aged kidney becomes more susceptible to acute injury has not been completely elucidated. In this study, we found that, compared with the kidneys of 3-month-old mice, the kidneys of 20-month-old mice expressed reduced levels of the renal protective molecule sirtuin 1 (SIRT1) and its cofactor NAD Supplementation with nicotinamide mononucleotide (NMN), an NAD precursor, restored renal SIRT1 activity and NAD content in 20-month-old mice and further increased both in 3-month-old mice.