Skip to content

Study · In vitro (cells) · 2017

2 results

Oleate ameliorates palmitate-induced reduction of NAMPT activity and NAD levels in primary human hepatocytes and hepatocarcinoma cells.

Penke M, Schuster S, Gorski T, Gebhardt R, Kiess W, Garten A

Lipids in health and disease3 Oct 2017Cited by 24 (Europe PMC)

PMID28974242 (opens in a new tab)PMCIDPMC5627432 (opens in a new tab)DOI10.1186/s12944-017-0583-6 (opens in a new tab)PepBankPUB-28974242
Download PDFPubMedAsk about this study
Jump to 2 results

Summary

BackgroundNicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide adenine dinucleotide (NAD) levels are crucial for liver function. The saturated fatty acid palmitate and the unsaturated fatty acid oleate are the main free fatty acids in adipose tissue and human diet. We asked how these fatty acids affect cell survival, NAMPT and NAD levels in HepG2 cells and primary human hepatocytes.MethodsHepG2 cells were stimulated with palmitate (0.5mM), oleate (1mM) or a combination of both (0.5mM/1mM) as well as nicotinamide mononucleotide (NMN) (0.5 mM) or the specific NAMPT inhibitor FK866 (10nM). Cell survival was measured by WST-1 assay and Annexin V/propidium iodide staining. NAD levels were determined by NAD/NADH Assay or HPLC. Protein and mRNA levels were analysed by Western blot analyses and qPCR, respectively. NAMPT enzyme activity was measured using radiolabelled 14C-nicotinamide. Lipids were stained by Oil red O staining.ResultsPalmitate significantly reduced cell survival and induced apoptosis at physiological doses. NAMPT activity and NAD levels significantly declined after 48h of palmitate. In addition, NAMPT mRNA expression was enhanced which was associated with increased NAMPT release into the supernatant, while intracellular NAMPT protein levels remained stable. Oleate alone did not influence cell viability and NAMPT activity but ameliorated the negative impact of palmitate on cell survival, NAMPT activity and NAD levels, as well as the increased NAMPT mRNA expression and secretion. NMN was able to normalize intracellular NAD levels but did not ameliorate cell viability after co-stimulation with palmitate. FK866, a specific NAMPT inhibitor did not influence lipid accumulation after oleate-treatment.ConclusionsPalmitate targets NAMPT activity with a consequent cellular depletion of NAD. Oleate protects from palmitate-induced apoptosis and variation of NAMPT and NAD levels. Palmitate-induced cell stress leads to an increase of NAMPT mRNA and accumulation in the supernatant. However, the proapoptotic action of palmitate seems not to be mediated by decreased NAD levels.
CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study2

2 results from studies that gave the peptide. No result from this study comes from people.

  1. 01LabIn vitro (cells)Mechanism

    In palmitate-stimulated HepG2 cells, NMN normalized intracellular NAD levels.

    In plain wordsIn cells exposed to palmitate, NMN restored NAD levels compared with palmitate without NMN.

    Peptide
    NMN (nicotinamide mononucleotide)
    Outcome
    IncreaseIntracellular NAD levels
    Study

    humann: not reported in source

    HepG2 cells
    Comparator
    palmitate without NMN
    Outcome group
    Mitochondrial function · Liver
    Studied dose
    0.5 mMAs given in this study (human).

    Source sentences

    Summary
    NMN was able to normalize intracellular NAD levels but did not ameliorate cell viability after co-stimulation with palmitate.
    1 context sentence
    Summary · context
    HepG2 cells were stimulated with palmitate (0.5mM), oleate (1mM) or a combination of both (0.5mM/1mM) as well as nicotinamide mononucleotide (NMN) (0.5 mM) or the specific NAMPT inhibitor FK866 (10nM).
  2. 02LabIn vitro (cells)Efficacy outcome

    In palmitate-stimulated HepG2 cells, NMN did not improve cell viability.

    In plain wordsIn cells exposed to palmitate, NMN did not improve cell survival compared with palmitate without NMN.

    Peptide
    NMN (nicotinamide mononucleotide)
    Outcome
    No significant changeCell viability
    Study

    humann: not reported in source

    HepG2 cells
    Comparator
    palmitate without NMN
    Outcome group
    Liver fat and liver function · Liver
    Studied dose
    0.5 mMAs given in this study (human).

    Source sentences

    Summary
    NMN was able to normalize intracellular NAD levels but did not ameliorate cell viability after co-stimulation with palmitate.
    1 context sentence
    Summary · context
    HepG2 cells were stimulated with palmitate (0.5mM), oleate (1mM) or a combination of both (0.5mM/1mM) as well as nicotinamide mononucleotide (NMN) (0.5 mM) or the specific NAMPT inhibitor FK866 (10nM).

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    21 Oct 2026, 15:58 UTC

    Study results updated

  2. Version 1

    21 Oct 2026, 12:50 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

PepBank is a research reference. Talk to a doctor before you use any peptide.