Metabolomics approach to growth-age discrimination in mountain-cultivated ginseng (Panax ginseng C. A. Meyer) using ultra-high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry.

Mountain-cultivated ginseng is typically harvested after 10 years, while ginseng aged over 15 years is considered wild ginseng. This study aims to differentiate mountain-cultivated ginseng by age, as the fraudulent practice of selling low-aged cultivated ginseng disguised as high-aged one is damaging the market. In this study, LC-MS analyzed 98 ginseng samples, and multivariate statistical analysis identified patterns between samples to select influential components. Machine learning models were developed to identify ginseng samples of different ages. The untargeted metabolomic analysis clearly divided samples aged 4-20 years into three age groups. Twenty-two potential age-dependent biomarkers were discovered to differentiate the three sample groups. Three machine learning models were used to predict new samples, and the optimal model was selected. Some biomarkers could determine age phases according to the differentiation of mountain-cultivated ginseng samples. These biomarkers were thoroughly analyzed for variation trends. The machine learning models established using the screened biomarkers successfully predicted the age group of new samples.

Zinc-finger-nucleases mediate specific and efficient excision of HIV-1 proviral DNA from infected and latently infected human T cells.

HIV-infected individuals currently cannot be completely cured because existing antiviral therapy regimens do not address HIV provirus DNA, flanked by long terminal repeats (LTRs), already integrated into host genome. Here, we present a possible alternative therapeutic approach to specifically and directly mediate deletion of the integrated full-length HIV provirus from infected and latently infected human T cell genomes by using specially designed zinc-finger nucleases (ZFNs) to target a sequence within the LTR that is well conserved across all clades. We designed and screened one pair of ZFN to target the highly conserved HIV-1 5'-LTR and 3'-LTR DNA sequences, named ZFN-LTR. We found that ZFN-LTR can specifically target and cleave the full-length HIV-1 proviral DNA in several infected and latently infected cell types and also HIV-1 infected human primary cells in vitro. We observed that the frequency of excision was 45.9% in infected human cell lines after treatment with ZFN-LTR, without significant host-cell genotoxicity. Taken together, our data demonstrate that a single ZFN-LTR pair can specifically and effectively cleave integrated full-length HIV-1 proviral DNA and mediate antiretroviral activity in infected and latently infected cells, suggesting that this strategy could offer a novel approach to eradicate the HIV-1 virus from the infected host in the future.

Zinc finger nuclease: a new approach for excising HIV-1 proviral DNA from infected human T cells.

A major reason that Acquired Immune Deficiency Syndrome (AIDS) cannot be completely cured is the human immunodeficiency virus 1 (HIV-1) provirus integrated into the human genome. Though existing therapies can inhibit replication of HIV-1, they cannot eradicate it. A molecular therapy gains popularity due to its specifically targeting to HIV-1 infected cells and effectively removing the HIV-1, regardless of viral genes being active or dormant. Now, we propose a new method which can excellently delete the HIV provirus from the infected human T cell genome. First, we designed zinc-finger nucleases (ZFNs) that target a sequence within the long terminal repeat (LTR) U3 region that is highly conserved in whole clade. Then, we screened out one pair of ZFN and named it as ZFN-U3. We discovered that ZFN-U3 can exactly target and eliminate the full-length HIV-1 proviral DNA after the infected human cell lines treated with it, and the frequency of its excision was about 30 % without cytotoxicity. These results prove that ZFN-U3 can efficiently excise integrated HIV-1 from the human genome in infected cells. This method to delete full length HIV-1 in human genome can therefore provide a novel approach to cure HIV-infected individuals in the future.

A novel method for age identification of mountain-cultivated ginseng.

Panax ginseng, a slow-growing perennial herb, is the most praised and popular traditional medicinal herb. Mountain-cultivated ginseng (MCG) and cultivated ginseng (CG) both belong to Panax ginseng C. A. Meyer. The market price and medical effects of this popular health product are closely related to its age. It is widely acknowledged that CG is typically harvested after 4-6 years of growth, but MCG is often collected after 10 years. Until now, the age identification of MCG or mountain wild ginseng (MWG) has remained a major challenge. In this study, we established a novel and rapid method for staining xylem vessels with phloroglucinol and identifying the "annual growth rings" of ginseng by utilizing a stereoscope, which serves as a reliable indicator of the age of MCG. Statistical analysis of the ring radius and the ring density of MCG aged from 1 to 20 years shows that the secondary xylem of MCG increases rapidly in the first 3 years but then gradually slows down from 4 to 10 years, and minor fluctuation is observed in the next 10 years. Meanwhile, the space between the growth rings (ring density) becomes increasingly small with age. This straightforward staining approach can reveal the age of MCG with remarkable clarity and can distinguish MCG from CG. RESEARCH HIGHLIGHTS: A novel rapid staining method for Panax ginseng was established. The age of mountain-cultivated ginseng (MCG) can be identified by microscopic techniques. MCG and cultivated ginseng (CG) can be discriminated by microstructure characteristics.