N-acetylcysteine promotes the proliferation of porcine adipose-derived stem cells during in vitro long-term expansion for cultured meat production.

Cultured meat is an efficient, safe and sustainable meat production technology. Adipose-derived stem cell (ADSC) is a promising cell type for cultured meat. In vitro, obtaining numerous of ADSCs is a pivotal step for cultured meat. In this research, we demonstrated that the proliferation and adipogenic differentiation of ADSCs significantly decreased during serial passage. Then, senescence ß-galactosidase (SA-ß-gal) staining showed that the positive rate of P9 ADSCs was 7.74-fold than P3 ADSCs. Subsequently, RNA sequencing (RNA-seq) was performed for P3 and P9 ADSCs and found that PI3K-AKT pathway was up-regulated, but cell cycle and DNA repair pathway were down-regulated in P9 ADSCs. Then, N-Acetylcysteine (NAC) was added during long-term expansion and showed that NAC enhanced the ADSCs proliferation and maintained adipogenic differentiation. Finally, RNA-seq was performed for P9 ADSCs cultured with or without NAC and showed that NAC restored the cell cycle and DNA repair pathway in P9 ADSCs. These results highlighted that NAC was an excellent supplement for large-scale expansion of porcine ADSCs for cultured meat.

Effects of long-term tea polyphenols consumption on hepatic microsomal drug-metabolizing enzymes and liver function in Wistar rats.

AIM: To investigate the effects of long-term tea polyphenols (TPs) consumption on hepatic microsomal drug-metabolizing enzymes and liver function in rats. METHODS: TPs were administered intragastrically to rats at the doses of 833 mg.kg(-1).d(-1) (n=20) and 83.3 mg.kg(-1).d(-1) (n=20) respectively for six months. Controlled group (n=20) was given same volume of saline solution. Then the contents of cytochrome P450, b5, enzyme activities of aminopyrine N-demethylase (ADM), glutathione S-transferase (GST) and the biochemical liver function of serum were determined. RESULTS: The contents of cytochrome P450 and b5 in the livers of male rats in high dose groups (respectively 2.66 +/- 0.55, 10.43 +/- 2.78 nmol.mg MS pro(-1)) were significantly increased compared with the control group (1.08 +/- 1.04, 5.51 +/- 2.98 nmol.mg MS pro(-1); P<0.01, respectively). The enzymatic activities of ADM in the livers of female rats in high dose groups (0.91 +/- 0.08 mmol.mg MS pro(-1)min(-1)) were increased compared with the control group (0.82 +/- 0.08 mmol.mg MS pro(-1).min(-1); P<0.05). The GST activity was unchanged in all treated groups, and the function of liver was not obviously changed. CONCLUSION: The antidotal capability of rats' livers can be significantly improved after long-term consumption of TPs. There are differences in changes of drug-metabolizing enzymes between the sexes induced by TPs and normal condition.