Mechanistic understanding of the inhibitory effect of cytochrome P450 3A4 and 3A5 by Wuzhi tablet (Schisandra sphenanthera extract) / 药学学报

Wuzhi tablet (WZ) is a prescribed herbal medicine extracted from Schisandra sphenanthera, which is widely used to protect the liver injury and drug-induced hepatotoxicity in clinical practices. Previous studies showed that WZ significantly increased the blood concentrations of tacrolimus, cyclosporine A, paclitaxel by inhibiting the cytochrome P450 3A (CYP3A)-mediated metabolism. CYP3A4 and CYP3A5 are the most important isoenzymes among the CYP3A subfamily. However, there are some differences in the catalytic and inhibitory activities between CYP3A4 and CYP3A5, which may lead to different risk of drug-drug and herb-drug interactions, and the risks may be further amplified in vivo. Currently, few reports have compared the herbal medicine inhibitory effects between CYP3A4 and CYP3A5 mediated metabolic reactions. Therefore, detailing the inhibitory effect of WZ on CYP3A4 and CYP3A5 will help understand and predict the potential herb-drug interaction. The results showed that WZ inhibited CYP3A4 and CYP3A5 in a NADPH-, time- and concentration- dependent manner. WZ showed more potent inhibition on CYP3A5 than CYP3A4. Cautions warranted when combining WZ with other therapeutic drugs to avoid the potential herb-drug interaction.

Wuzi Yanzong pill, a Chinese polyherbal formula, alleviates testicular damage in mice induced by ionizing radiation.

BACKGROUND: Chinese medicine Wuzi Yanzong pill (WZYZP) was firstly documented in ancient Chinese medical works "She Sheng Zhong Miao Fang" by Shi-Che Zhang in 1550 AD. The traditional herbal formula is widely used in treating nephrasthenia lumbago, prospermia, erectile dysfunction and male sterility. The present study was to explore the effects of WZYZP on ionizing irradiation-induced testicular damage in mice. METHODS: The pelvic region of male mice was exposed to X-rays for inducing testicular damage. The effects of WZYZP on testicular damage were evaluated in terms of testes weight, sperm quantity and motility, testes oxidative status and serum hormone levels. The alterations in testicular structure were examined by hematoxylin-eosin staining. Additionally, changes in proliferating cell nuclear antigen (PCNA) expression of testes were explored by western blot. RESULTS: Pelvic exposure to x-ray induced reduction in testes weight and sperm quality, along with oxidative stress and abnormal testicular architecture in testes. Oral administration of WZYZP for 3 weeks markedly increased testes weight, sperm quantity and motility, and attenuated testicular architecture damage. Meanwhile, WZYZP treatment significantly reversed the reduction of serum testosterone, and decreased testes malondialdehyde (MDA) and Oxidative stress index (OSI) relative to the radiated mice. Additionally, WZYZP effectively prevented the downregulation of PCNA expression in testes induced by x-ray irradiation. CONCLUSION: These findings suggest WZYZP exhibits ameliorating effects against ionizing irradiation-induced testicular damage in mice, which may be related to its antioxidation.

Study on scavenging activity to DPPH free radical of different polarity components in Guizhou Miao medicine "bod zangd dak" / 中国中药杂志

The paper is aimed to search more natural plant antioxidants and further research and develop new medicinal plant resources in Guizhou. The Guizhou special miao medicine "bod zangd dak" was extracted with 60% ethanol. The antioxidant activity of the different polarity components separated from the extract was tested by DPPH method with ascorbic acid as positive control. The results showed that the IC50 of the different polarity components was as following: ascorbic acid (0.033 4 g x L(-1)) < ethyl acetate components (0.052 3 g x L(-1)) < total tannins components (0.054 9 g x L(-1)) < 60% ethanol extraction components (0.076 7 g x L(-1)) < butanol extraction components (0.110 g x L(-1)) < water-soluble polysaccharides components (0.168 g x L(-1)) < water extraction components (0.174 g x L(-1)) < water components after extraction (0.226 g x L(-1)) < total polysaccharides components (0.645 g x L(-1)). It is concluded that the different polarity components have different free radical scavenging activity and that provides a scientific basis for further search of the active ingredients and the activive mechanism.

Protective effects of green tea extracts on photoaging and photommunosuppression.

OBJECTIVES: This study aimed to investigate whether the sunscreen-containing 2-5% green tea extracts (GTEs) protect ultraviolet irradiation (UVR)-induced photoaging and photoimmunosuppression. MATERIALS AND METHODS: Twenty volunteers were exposed to repetitive solar-simulated UVR (ssUVR) on the upper back at a dosage of 1.5 minimal erythema doses (MED) per day for four consecutive days. Thirty minutes before each UVR and 6, 24, and 48 h after the last UV exposure, the products containing vehicle, and 2-5% GTEs were applied onto five sites on the dorsal skin, respectively. The skin biopsies were obtained 72 h after the last UVR. The thickness of the stratum corneum and epidermis was measured under the microscope and the expression of cytokeratins (CK)-5/6, CK16, metalloproteinases (MMP)-2, MMP-9, and the CD1a(+) Langerhans cells (LCs) were determined using immunohistochemistry. RESULTS: Our results showed that UVR substantially induced cutaneous erythema, thickening of the epidermis, overexpression of CK5/6, CK16, MMP-2, MMP-9, and depletion of CD1a(+) LCs. The sunscreens containing different concentrations of GTEs conferred significant protection against the photoaging and photoimmunology-related biological events. Interestingly, the protective effects were not parallel to the concentrations of GTEs, with 2% and 3% GTEs showing the most efficacious photoprotection. CONCLUSIONS: GTEs-containing sunscreens have potential photoprotective effects on UVR-induced photoaging and photoimmunosuppression.