Purification of Polysaccharides from Orostachys cartilaginous Cell Cultures by Macroporous Resin Absorption and Bioactivities of the Purified Polysaccharides.

Orostachys cartilaginous is a traditional herbal medicine and its cell cultures contain large amounts of polysaccharides. To utilize the cultured O. cartilaginous cells, this study purified the crude polysaccharides of O. cartilaginous cells by macroporous resin absorption and optimized the purification process in the experiment of orthogonal design with four factors (sample concentration and volume, and eluent concentration and volume) and three levels; the antibacterial and anti-cancer effects of the purified polysaccharides (OTP) were further examined. The results showed that polysaccharide purity reached 95 % in the optimized group, i. e., 1.6 mg/mL of sample (crude polysaccharides) concentration, 3.0 bed volume (BV) of sample volume, 65 % eluent (ethanol) concentration, and 3.0 BV of eluent volume. In the antibacterial experiment, the growth of three bacterial species, i. e., Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis was inhibited by OTP, whereas that of Escherichia coli was not affected; the largest diameter of the inhibitory zone was found on B. subtilis; the extracellular alkaline phosphatase activity and the electrical conductivity, nucleic acid, and protein levels of B. subtilis increased after OTP treatment, indicating that the inhibition of B. subtilis growth was caused by the leakage of cell contents. In the anti-cancer experiment, OTP decreased the cell viabilities of the tested human cancer cells, i. e., AGS (gastric cancer), HCT116 (colon cancer), HepG2 (liver cancer), and HeLa (cervical cancer), and the highest inhibitory effect was on HCT116. OTP promoted HCT116 apoptosis and affected the expression of apoptosis-related proteins, i. e., the expression of B-cell lymphoma-2 decreased and that of bcl-2 associated X protein, cytochrome c, caspase 9 and caspase 3 increased. The findings of the present study suggest that O. cartilaginous cell cultures have a potential application in food or drug production.

Removing crosstalk signals in neuron activity by time multiplexed excitations in a two-photon all-optical physiology system.

The two-photon all-optical physiology system has attracted great interest in deciphering neuronal circuits in vivo, benefiting from its advantages in recording and modulating neuronal activities at single neuron resolutions. However, the interference, or crosstalk, between the imaging and photostimulation beams introduces a significant challenge and may impede the future application of voltage indicators in two-photon all-optical physiology system. Here, we propose the time multiplexed excitation method to distinguish signals from neuronal activities and crosstalks from photostimulation. In our system, the laser pulses of the imaging beam and photostimulation beam are synchronized, and a time delay is introduced into these pulses to separate the fluorescence signal generated by these two beams. We demonstrate the efficacy of our system in eliminating crosstalk signals from photostimulation and evaluate its influence on both genetically encoded calcium indicators (GECIs) and genetically encoded voltage indicators (GEVIs) through in vivo experiments.

Adult newborn granule cells confer emotional state-dependent adaptability in memory retrieval.

Achieving optimal behavior requires animals to flexibly retrieve prior knowledge. Here, we show that adult newborn granule cells (anbGCs) mediate emotional state-dependent adaptability of memory retrieval. We find that acute social reward (aSR) enhances memory retrieval by increasing the reactivation of engram cells, while acute social stress (aSS) weakens retrieval and reduces the reactivation. Such bidirectional regulation relies on the activation of distinct populations of anbGCs by aSR and aSS, triggering opposing modifications of dDG activity, which is sufficient to regulate and predict the performance of memory retrieval. Concordantly, in emotional disorder models, aSR-dependent memory adaptability is impaired, while the effect of aSS remains intact. Together, our data revealed that anbGCs mediate adaptability of memory retrieval, allowing animals to flexibly retrieve memory according to the current emotional state, and suggested the essential roles of anbGCs in translating emotional information to the regulation of memory expression.

Selection of initial culture medium in fed-batch bioreactor culture of Rhodiola sachalinensis cells.

In fed-batch culture, numerous factors, such as initial culture conditions and feeding strategies, affect the culture efficiency. Among the factors, the effect of initial culture medium is rarely investigated. In this work, Rhodiola sachalinensis cells were cultured in the fed-batch bioreactor system and the effects of volume, medium strength, and sucrose concentration of initial culture medium on biomass and accumulation of salidroside, polysaccharides, flavonoids, and phenolics were investigated. The results showed that an initial medium volume of 3 L significantly (p < 0.05) increased biomass and the four bioactive compound contents. The maximum biomass and the highest contents of different bioactive compounds were determined at various MS medium strengths. Therefore, analytic hierarchy process (AHP) - technique for order preference by similarity to ideal solution (TOPSIS) was implemented and half-strength MS medium was selected. Furthermore, the effect of sucrose concentration was examined and 30 g/L sucrose in the initial medium was optimal, at which concentration, 39.45 mg/g DW of salidroside, 531.25 mg/g DW of total polysaccharides, 3.89 mg/g DW of total flavonoids, and 10.84 mg/g DW of total phenolics were produced. The findings of the present study provided a reference for further establishing the fed-batch culture system of R. sachalinensis cells.

Hepatoprotective Effect of Oplopanax elatus Nakai Adventitious Roots Extract by Regulating CYP450 and PPAR Signaling Pathway.

O. elatus Nakai is a traditional medicine that has been confirmed to exert effective antioxidant and anti-inflammatory functions, and is used for the treatment of different disorders. However, its potential beneficial effects on drug induced hepatotoxicity and relevant molecular mechanisms remain unclear. This study investigated the protective effect and further elucidated the mechanisms of action of O. elatus on liver protection. O. elatus chlorogenic acids-enriched fraction (OEB), which included chlorogenic acid and isochlorogenic acid A, were identified by HPLC-MS/MS. OEB was administrated orally daily for seven consecutive days, followed by a single intraperitoneal injection of an overdose of APAP after the final OEB administration. The effects of OEB on immune cells in mice liver were analyzed using flow cytometry. APAP metabolite content in serum was detected using HPLC-MS/MS in order to investigate whether OEB affects CYP450 activities. The intestinal content samples were processed for 16 s microbiota sequencing. Results demonstrated that OEB decreased alanine aminotransferase, aspartate aminotransferase contents, affected the metabolism of APAP, and decreased the concentrates of APAP, APAP-CYS and APAP-NAC by inhibiting CYP2E1 and CYP3A11 activity. Furthermore, OEB pretreatment regulated lipid metabolism by affecting the peroxisome proliferator-activated receptors (PPAR) signaling pathway in mice and also increased the abundance of Akkermansia and Parabacteroides. This study indicated that OEB is a potential drug candidate for treating hepatotoxicity because of its ability to affect drug metabolism and regulate lipid metabolism.