Nootkatone Mitigated Melamine-Evoked Hepatotoxicity by Featuring Oxidative Stress and Inflammation Interconnected Mechanisms: In Vivo and In Silico Approaches

Melamine (ML) is a common environmental contaminant, commonly used in food fraud, representing a serious health hazard and jeopardizing human and animal health. Recently, nootkatone (NK), a naturally occurring sesquiterpenoid, has garnered considerable attention due to its potential therapeutic advantages. We investigated the potential mechanisms underlying the protective effects of NK against ML-induced liver injury in rats. Five groups were utilized: control, ML, NK10, ML-NK5, and ML-NK10. ML induced substantial hepatotoxicity, including considerable alterations in biochemical parameters and histology. The oxidative distress triggered by ML increased the generation of malondialdehyde (MDA) and nitric oxide (NO) and decreased levels of reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) activities. In addition, decreased expression of nuclear factor-erythroid 2-related factor 2 (Nrf2) and increased nuclear factor kappa beta (NF-κB) expression levels were observed in hepatocytes, which indicated the occurrence of inflammatory changes following ML exposure. These alterations were alleviated by NK supplementation in a dose-dependent manner. The data revealed that the favorable effects of NK were attributed, at least in part, to its antioxidant and anti-inflammatory properties. Moreover, our results were supported by molecular docking studies that revealed a good fit and interactions between NK and antioxidant enzymes. Thus, the current study demonstrated that NK is a potential new food additive for the prevention or treatment of ML-induced toxicity.

Enhancing ex vivo expansion of cord blood-derived unrestricted somatic stem cells for clinical applications

OBJECTIVES

To study effects of serum-containing medium (SCM) versus serum-free medium (SFM) and influence of seeding density, on rate of expansion of cord blood (CB) unrestricted somatic stem cells (USSCs), as a prerequisite for evaluating their therapeutic potential in ongoing clinical trials.

MATERIAL AND METHODS

Isolation, propagation and characterization of USSCs from CB samples were performed and followed by their passage 3 culture in SCM and SFM, at cell densities of 5, 50, 500 and 5000 cells/cm(2) .

RESULTS

The cells were CD44(+) , CD90(+) , CD73(+) , CD105(+) , CD34(-) , CD45(-) , and HLA-DR, with Oct4 & Sox2 gene expression; they were differentiated into osteoblasts and adipocytes. USSCs cultured in SCM had significantly higher population doubling levels (P < 0.01) than those cultured in SFM. Those cultured in SCM at 5 cells/cm(2) and those cultured in SFM at 50 cells/cm(2) had significantly higher population doubling (P < 0.01) levels than those cultured at higher cell densities.

CONCLUSIONS

For scaling up of USSCs from 106 (?) to 1012 (?) in 6 weeks, culturing of CB-derived cells of early passage (≤P3) in SCM at low cell seeding density (5 cells/cm(2) ) is suggested for increasing cell count with lower passaging frequency, followed by culture of expanded USSCs at 50 cells/cm(2) in SFM, to avoid undesirable effects of bovine serum in clinical applications.