Preventive Effect of Small-Leaved Kuding Tea (Ligustrum robustum (Roxb.) Bl.) Polyphenols on D-Galactose-Induced Oxidative Stress and Aging in Mice

Abstract

Small-leaved Kuding tea is a traditional Chinese tea that is rich in polyphenols. In the current study, we investigated the preventive effect of small-leaved Kuding tea (SLKDT) on D-galactose-induced oxidative aging in mice. Changes in serum, skin, liver, and spleen of experimental animals were determined using biochemical and molecular biology techniques. Biochemical analysis demonstrated that polyphenol extract of SLKDT (PSLKDT) improved the indices of the thymus, brain, heart, liver, spleen, and kidney function in model mice. PSLKDT prevented a decrease in the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione (GSH) as well as an increase in nitric oxide (NO) and malondialdehyde (MDA) levels in serum, liver, and spleen. Pathological assessment also showed that PSLKDT reduced oxidative damage induced by D-galactose in skin, liver, and spleen. We further found that PSLKDT upregulated neuronal nitric oxide synthase (nNOS), endothelial nitric oxide synthase (eNOS), Cu/Zn-SOD, Mn-SOD, catalase (CAT), heme oxygenase-1 (HO-1), nuclear factor (nuclear factor-erythroid 2 related factor 2 (Nrf2), γ-glutamylcysteine synthetase (γ-GCS), and NAD(P)H dehydrogenase [quinone] 1 (NQO1) mRNA expression and downregulated inducible nitric oxide synthase (iNOS) mRNA expression. Protein levels of SOD1 (Cu/Zn-SOD), SOD2 (Mn-SOD), CAT, GSH1 (γ-glutamate-cysteine ligase), and GSH2 (glutathione synthetase) in the liver and spleen were also increased by PSLKDT treatment. Collectively, these results indicate that PSLKDT is effective in preventing D-galactose-induced oxidative aging in mice, and its efficacy is significantly higher than antioxidant vitamin C. Because PSLKDT is a potent antioxidant and antiaging polyphenol, Kuding tea rich in PSLKDT should be considered an ideal drink with antioxidative and antiaging effects.

Galactose-Induced Skin Aging: The Role of Oxidative Stress

“…Aging models based on the administration of D-gal have been intensively utilized for validation of the antiaging efficacy of natural antioxidant compounds over the last decades [148]. In fact, the antioxidant properties of polyphenols have been tested in a number of studies using a model of skin aging based on the use of D-gal [149][150][151][152].…”

The effect of Malus doumeri leaf flavonoids on oxidative stress injury induced by hydrogen peroxide (H2O2) in human embryonic kidney 293 T cells

“…According to the experimental operation of MDLF on oxidative damage induced by H 2 O 2 in HEK 293 T cells, the cells were cultured and treated with MDLF for 48 h; then the cells were fixed, and apoptosis was detected by flow cytometry after staining (AccuriC6, BD Biosciences, San Jose, CA, USA) [23].…”

Effect of Zhongyi paste on inflammatory pain in mice by regulation of the extracellular regulated protein kinases 1/2–cyclooxygenase-2–prostaglandin E2 pathway

“…The reaction conditions were denaturation at 95℃ for 3 minutes, annealing at 60℃ for 30 secconds, and extension at 95℃ for 1 minute, for 40 cycles. The relative expression intensity of each gene to be tested for mice in the model group was calculated by the 2-∆∆Ct method through the measured cycle threshold value [ 17 ].…”