NAD;β-Nicotinamide adenine dinucleotide,diphosphopyridine nucleotide

Basic Information

• Chemical Name: β-Nicotinamide adenine dinucleotide (β-NAD⁺), also known as diphosphopyridine nucleotide (DPN)
• CAS Number: 53-84-9
• Molecular Formula:
  • Anhydrous: \(\text{C}_{21}\text{H}_{27}\text{N}_{7}\text{O}_{14}\text{P}_{2}\)
  • Hydrated: \(\text{C}_{21}\text{H}_{27}\text{N}_{7}\text{O}_{14}\text{P}_{2} \cdot x\text{H}_2\text{O}\)
• Molecular Weight:
  • Anhydrous: 663.43 g/mol
  • Hydrated: Varies with water content (e.g., 759.2 g/mol for decahydrate)
• Classification: Pyridine nucleotide coenzyme, derived from vitamin B3 (niacin).

Description

Physical Properties

• Appearance: White to off-white crystalline powder.
• Solubility:
  • Soluble in water (40 mg/mL at 25°C) and polar solvents (e.g., ethanol) 2.
  • Insoluble in non-polar solvents (e.g., chloroform).
• Stability:
  • pH Sensitivity: Stable at neutral pH (6.5–8.5) but hydrolyzes in acidic conditions.
  • Thermal Stability: Decomposes at high temperatures (>218°C) without melting 6.
  • Storage: Requires refrigeration (-20°C) to prevent degradation.

Chemical Structure

1. Nicotinamide moiety: A pyridine ring with an amide group.
2. Adenine moiety: A purine ring linked to ribose.
3. Two phosphate groups: Connecting the ribose sugars via a pyrophosphate bond. This structure allows reversible redox reactions (NAD⁺/NADH cycle) critical for cellular energy metabolism 2.

Key Data

• Purity:
  • Pharmaceutical Grade: ≥99% (HPLC) 3.
  • Research Grade: ≥95% (HPLC) 6.
• Optical Rotation: \([\alpha]_D^{20} = +21.5° \text{ to } +26.5°\) (3% aqueous solution) 2.
• UV Absorption: Maximum absorbance at 260 nm (due to adenine and nicotinamide rings).
• Melting Point: Decomposes at ~218°C 6.
• pH (3% Solution): 7.0–8.5 6.

Functions

Core Biological Roles

1. Redox Reactions:
   • Acts as an electron carrier in glycolysis, the citric acid cycle, and oxidative phosphorylation, generating ATP 2.
   • NAD⁺/NADH Cycle: Shuttles electrons between catabolic (e.g., glucose breakdown) and anabolic (e.g., lipid synthesis) pathways.
2. Energy Metabolism:
   • Essential for mitochondrial ATP production, critical for cellular energy homeostasis.
3. DNA Repair & Aging:
   • Activates poly(ADP-ribose) polymerases (PARPs) to repair DNA damage 9.
   • Serves as a co-substrate for sirtuins (e.g., SIRT1), which regulate aging and metabolic pathways 9.
4. Neurotransmission:
   • Emerging evidence suggests β-NAD⁺ acts as an inhibitory neurotransmitter in visceral smooth muscles and the central nervous system 1 7.
5. Cell Signaling:
   • Involved in calcium signaling and immune responses (e.g., NLRP3 inflammasome regulation) 10.

Applications

Pharmaceuticals & Therapeutics

• Myocardial Ischemia/Reperfusion Injury: Intravenous NAD⁺ reduces infarct size and apoptosis in animal models 2.
• Neurodegenerative Diseases: Investigated for Alzheimer’s and Parkinson’s disease due to its neuroprotective effects 9.
• Diabetes: May improve insulin sensitivity and endothelial function 9.

Cosmetics & Skincare

• Anti-Aging: Enhances collagen production and reduces UV-induced damage (e.g., Filorga’s NCEF products) 17.
• Skin Barrier Repair: Used in creams to improve hydration and reduce inflammation 18.

Research & Biotechnology

• Enzyme Assays: Critical for monitoring dehydrogenase activities (e.g., lactate dehydrogenase).
• Cell Culture: Boosts cell viability and metabolic activity in vitro 2.

Food & Beverages

• Functional Foods: Added to energy drinks and supplements to enhance stamina and recovery.
• Preservative: Extends shelf life by inhibiting lipid peroxidation