Expression of Multicopy Tandem Recombinant Ginseng Hexapeptide in Bacillus subtilis and the Evaluation of Antiaging Activity.

Ginseng oligopeptides are naturally occurring small-molecule peptides extracted from ginseng that exhibit positive effects on health and longevity. However, the current industrial production of ginseng oligopeptides primarily relies on plant extraction and chemical synthesis. In this study, we proposed a novel genetic engineering approach to produce active ginseng peptides through multicopy tandem insertion (5 and 15 times). The recombinant ginseng peptides were successfully produced from engineered Bacillus subtilis with an increasing yield from 356.55 to 2900 mg/L as the repeats multiple. Additionally, an oxidative stress-induced aging model caused by H2O2 was established to evaluate whether the recombinant ginseng peptides, without enzymatic hydrolysis into individual peptides, also have positive effects on antiaging. The results demonstrated that all two kinds of recombinant ginseng peptides could also delay cellular aging through various mechanisms, such as inhibiting cell cycle arrest, suppressing the expression of pro-inflammatory factors, and enhancing cellular antioxidant capacity.

Ginsenoside Rk3 is a novel PI3K/AKT-targeting therapeutics agent that regulates autophagy and apoptosis in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. Ginsenoside Rk3, an important and rare saponin in heat-treated ginseng, is generated from Rg1 and has a smaller molecular weight. However, the anti-HCC efficacy and mechanisms of ginsenoside Rk3 have not yet been characterized. Here, we investigated the mechanism by which ginsenoside Rk3, a tetracyclic triterpenoid rare ginsenoside, inhibits the growth of HCC. We first explored the possible potential targets of Rk3 through network pharmacology. Both in vitro (HepG2 and HCC-LM3 cells) and in vivo (primary liver cancer mice and HCC-LM3 subcutaneous tumor-bearing mice) studies revealed that Rk3 significantly inhibits the proliferation of HCC. Meanwhile, Rk3 blocked the cell cycle in HCC at the G1 phase and induced autophagy and apoptosis in HCC. Further proteomics and siRNA experiments showed that Rk3 regulates the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway to inhibit HCC growth, which was validated by molecular docking and surface plasmon resonance. In conclusion, we report the discovery that ginsenoside Rk3 binds to PI3K/AKT and promotes autophagy and apoptosis in HCC. Our data strongly support the translation of ginsenoside Rk3 into novel PI3K/AKT-targeting therapeutics for HCC treatment with low toxic side effects.

Hepatoprotective effects of ginsenoside Rk3 in acetaminophen-induced liver injury in mice by activation of autophagy.

Acetaminophen (APAP)-induced acute liver injury (AIALI) is one of the most common causes of acute liver failure. Owing to the limitations of N-acetylcysteine (NAC), which is the only antidote currently used in clinical practice for APAP, there is a need to develop new therapies that can provide extensive protection against AIALI. Ginsenoside Rk3 is a rare ginsenoside extracted from Panax notoginseng and a previous study has reported its excellent hepatoprotective function. In this study, we explored the therapeutic potential of ginsenoside Rk3 in APAP-induced acute liver injury. We found that ginsenoside Rk3 could reduce APAP-induced hepatotoxicity by reducing serum alanine aminotransferase and aspartate aminotransferase activity and pathological damage to the liver. Moreover, ginsenoside Rk3 could inhibit APAP-induced liver inflammation and oxidative stress by inhibiting the production of oxidative molecules, increasing the production of antioxidant molecules, and reducing the infiltration of inflammatory cells and the production of pro-inflammatory cytokines. Further mechanistic investigations revealed that the therapeutic effect of ginsenoside Rk3 was mainly dependent on the continuous activation of autophagy. Chloroquine, an autophagy inhibitor, was found to inhibit these protective effects. Therefore, ginsenoside Rk3 shows potential as a novel hepatoprotective agent to prevent drug-induced liver injury.

Ginsenoside Rg5/Rk1 ameliorated sleep via regulating the GABAergic/serotoninergic signaling pathway in a rodent model.

As the most common sleep disorder, insomnia seriously affects people's everyday lives. Phytochemicals have been shown to have excellent sleep-promoting effects. Therefore, this study was designed to investigate whether Rg5 and Rk1 extracted from ginseng had sleep-promoting effects and to explore their potential mechanisms. The results showed that Rg5 and Rk1 could significantly lessen the locomotor activity of mice and promote the sleep quality index, including increasing the amount of sleep in a pentobarbital sodium experiment with a threshold dose. In parallel, Rg5 and Rk1 could significantly shorten the sleep latency of mice and prolong the sleep time of mice. Furthermore, Rg5 and Rk1 augmented the GABA/Glu ratio, up-regulating the expression of the GABAA receptor and the GABAB receptor, whereas the GABAA receptor antagonist picrotoxin could antagonize the sleep quality of Rg5/Rk1. In addition, 5-HTP, the precursor of 5-HT, could enhance the sleep effect of Rg5 and Rk1 in mice, and both Rg5 and Rk1 could up-regulate the expression of 5-HT1A. These results were also confirmed by the detection of GABA and 5-HT in mouse cecum content. In conclusion, ginsenoside Rg5/Rk1 can exert sedative and hypnotic effects by affecting the GABA nervous system and the serotonin nervous system.

Kiwifruit seed oil prevents obesity by regulating inflammation, thermogenesis, and gut microbiota in high-fat diet-induced obese C57BL/6 mice.

Obesity is considered as a chronic disease which seriously affecting people's health and daily life. Kiwifruit (Actinidia chinensis Planch) seed oil (KSO), as a by-product of kiwifruit processing, is rich in fatty acids. Conventional wisdom holds that KSO has many health benefits, but there is no scientific basis. Here, the relieving effects of KSO on obesity and its potential mechanism were investigated in high-fat diet (HFD)-induced C57BL/6 mice. Mice were divided into four groups: ND (normal diet); HFD; L-KSO and H-KSO (HFD supplemented with 1.0 and 3.0 mL/kg·bw of KSO per day, respectively). Results showed that continuous supplementation KSO for 12 weeks significantly decreased bodyweight, inguinal fat tissue weight, blood glucose, and HOMA-IR index and ameliorated serum lipids accumulation (TC, TG, HDL-C, and LDL-C). Relative mRNA expression of inflammatory cytokines (TNF-α, IL-6, IL-1ß, COX-2, and iNOS) was down-regulated and expression of thermogenesis-related genes (PPAR-γ, UCP1, PGC1-α, and PRDM16) was up-regulated in the inguinal fat tissue of KSO treated mice. Principal component analysis showed that the microbial community compositions of four groups were different. KSO supplementation dramatically decreased the Firmicutes-to-Bacteroidetes ratio. Together, our findings demonstrated that long-term supplementation KSO ameliorates obesity by reducing inflammation, adipose thermogenesis and gut microbiota dysbiosis.