The ovarian-related effects of polystyrene nanoplastics on human ovarian granulosa cells and female mice.

Nanoplastics (NPs) have recently emerged in the context of global plastic pollution. They may be more toxic than macroplastics litter and microplastic fragments due to its abundances, tiny sizes, and cellular accessibility. The female reproductive toxicity of NPs has been widely documented for aquatic animals, but their effects and underlying mechanisms remain poorly understood in mammals. This study aimed to explore the effects of NPs on female reproduction using human ovarian granulosa cells (GCs) and female mice. The accumulation of polystyrene NPs (PS-NPs) in human granulosa-like tumor cells (KGN cells) and the ovaries of female Balb/c mice were evaluated by exposure to fluorescent PS-NPs. Proliferation and apoptosis, reactive oxygen species (ROS), and Hippo signaling pathway-related factors were analyzed in KGN cells. In addition, fertility rate, litter size, ovarian weight and microstructure, follicle development, serum level of anti-Mullerian hormone, and apoptosis in ovaries were examined in female mice. Here, the PS-NPs can penetrate the KGN cells and accumulate in the ovaries. In vitro, 100 µg/ml PS-NPs inhibited proliferation, induced apoptosis, accumulated ROS, activated three key regulators of the Hippo signaling pathway (MST1, LATS1, and YAP1), and downregulated the mRNA levels of CTGF and Cyr61 in KGN cells. Furthermore, salidroside, an antioxidative compound extracted from Rhodiola rosea, alleviated the damage of PS-NPs to KGN and inhibited the activation of the Hippo signal pathway. In vivo, exposure to 1 mg/day PS-NPs resulted in decreased fertility, abnormal ovarian function, and increased ovarian apoptosis in female mice. Overall, our data suggest that PS-NPs cause granulosa cell apoptosis and affect ovarian functions, leading to reduced fertility in female mice, by inducing oxidative stress and dysregulating the Hippo pathway.

ApoE-modified liposomes encapsulating resveratrol and salidroside alleviate manifestations of Alzheimer's disease in APP/PS-1 mice.

OBJECTIVE: Alzheimer's disease (AD) is a neurodegenerative disease that is associated with aging and is influenced by both genetic and environmental factors. Several studies and clinical trials have demonstrated that resveratrol (Res) and salidroside (Sal) are not only biologically safe but also influence AD biomarker trajectories. However, their clinical applications have been quite limited due to poor specificity, low solubility, and insufficient blood-brain barrier (BBB) penetration. Therefore, we developed a nano-drug delivery system in which Res and Sal were encapsulated in liposomes, which were surface-modified with ApoE (ApoE-Res/Sal-Lips) to compensate for these deficiencies. METHOD: In this study, ApoE-Res/Sal-Lips were prepared using a standard thin-film hydration method for liposomes. Then, cellular uptake of the loaded liposomes was assessed in vitro using fluorescent staining assays. A BBB model was constructed to investigate the capacity of the liposomes to cross the BBB in vitro, and the ability of liposomes to target the brain was observed by in vivo imaging. In addition, the neuroprotective effects of the different liposome formulations in APP/PS-1 mice were evaluated by measuring the changes in levels of oxidative, anti-inflammatory, and anti-apoptotic factors in the mice brains. RESULTS: In vitro, ApoE-Res/Sal-Lips increased the uptake of Res and Sal by bEnd.3 and N2a cells, enhanced BBB penetration, and improved transport efficiency. In vivo, the ApoE-Res/Sal-Lips were found to alleviate AD pathological symptoms, reduce learning and memory impairments, and improve brain function. CONCLUSION: ApoE-Res/Sal-Lips provide a new method for the treatment of AD.

Preparation and Characterization of PLGA-PEG-PLGA Nanoparticles Containing Salidroside and Tamoxifen for Breast Cancer Therapy.

Nanoparticles (NPs) containing the hydrophilic drug salidroside (Sal) and the hydrophobic drug tamoxifen (Tam) were prepared using a triblock copolymer poly(lactic-co-glycolic acid) (PLGA)-poly(ethylene glycol) (PEG)-PLGA to achieve synergism in the treatment of breast cancer. The double emulsion (w/o/w) method was used to prepare Sal-Tam NPs with an average particle size of 275.3 ± 44.0 nm, a polydispersity index of 0.302 ± 0.102, and a zeta potential of - 6.98 ± 2.99. The entrapment efficiency of the hydrophilic and hydrophobic components was 32.63% ± 0.73% and 49.18% ± 3.04%, respectively. On differential scanning calorimetry, the NPs showed the amorphous nature of both Sal and Tam. The sustained release of Sal and Tam from the NPs was significantly prolonged under physiological conditions (pH 7.4). The CCK-8 assay using the 4T1 cell line revealed a 1.7-fold decrease in the IC50 value for Sal-Tam NPs when compared with free Tam. The in vivo anti-tumor effect was assessed in BALB/c mice, and the results demonstrated that these NPs decreased the tumor volume compared with saline and showed high anti-tumor activity. A pharmacokinetic study showed significant enhancement of the bioavailability of Tam in Sal-Tam NPs compared with free Tam in suspension. The intracellular and mitochondrial anti-oxidative effect of Sal was thought to be attributed to the promising anti-tumor effect of drug co-delivery. This study confirmed that the use of Sal-Tam NPs may be a promising approach in breast cancer therapy.

Simultaneous Preparation of Salidroside and p-Tyrosol from Rhodiola crenulata by DIAION HP-20 Macroporous Resin Chromatography Combined with Silica Gel Chromatography.

The Rhodiola species have a long history of utilization in traditional medicine and have been considered as a source of adaptation to environmental challenges; salidroside and p-tyrosol are the major responsible compounds. Here we propose a novel UPLC-guided two-step method consisting of a DIAION HP-20 adsorption and silica gel column chromatographies, which can simultaneously prepare high purities of salidroside and p-tyrosol with noticeable yields from the rhizome of Rhodiola crenulata. Results demonstrated that DIAION HP-20 could successfully remove all impurities except crenulatin during a gradient elution with 5⁻20% ethanol, which could achieve an optimal purification of salidroside and p-tyrosol with increasing rates of 29.19% and 33.44%, respectively. Furthermore, chloroform was selected as an ideal solvent for separating p-tyrosol with salidroside, and thus crenulatin was subsequently applied in the silica gel chromatography, and the separation of salidroside with crenulatin could be achieved using silica gel chromatography with a mixture of chloroform and methanol at a volume ratio of 4:1. High purity rates of 94.17% and 97.29% and overall yields of 39.09% and 43.73% for salidroside and p-tyrosol were simultaneously achieved. Our method provides a new way to simultaneously obtain salidroside and p-tyrosol from R. Crenulata, as well as other related plant species.

Angiopep-2 modified dual drug-loaded liposomes with brain targeting functionality mitigate Alzheimer's disease-related symptoms in APP/PS-1 mice.

The blood-brain barrier (BBB) is a barrier that maintains brain homeostasis, but it is also one of the major problems that must be overcome in the development of Alzheimer's disease (AD) drugs. To solve this problem, Salidroside (Sal) and Icariin (Ica), drugs with neuroprotective effects were loaded into liposomes, and the targeting molecule Angiopep-2 was modified on the surface of liposomes (Ang-Sal/Ica-Lip), so that the constructed nano-drug delivery system could effectively cross the BBB and exert anti-AD effects. The prepared liposomes exhibited ideal physicochemical properties. In vitro and in vivo targeting studies showed that Ang-Sal/Ica liposome could cross the BBB to increase drug accumulation in the brain, and increase the uptake of N2a cells and bEnd.3 cells. The pharmacodynamic analysis in vivo showed that Ang-Sal/Ica liposome could reverse neuronal and synaptic damage, inhibit neuroinflammation and oxidative stress and improve learning and cognitive function. Therefore, Ang-Sal/Ica liposome may be a promising therapeutic strategy for mitigating AD-related symptoms.

Salidroside promotes the osteogenic and odontogenic differentiation of human dental pulp stem cells through the BMP signaling pathway.

Regenerative endodontics, as an alternative approach, aims to regenerate dental pulp-like tissues and is garnering the attention of clinical dentists. This is due to its reported biological benefits for dental therapeutics. Stem cells and their microenvironment serve an important role in the process of pulp regeneration. Regulation of the stem cell microenvironment and the directed differentiation of stem cells is becoming a topic of intensive research. Salidroside (SAL) is extracted from the root of Rhodiola rosea and it has been reported that SAL exerts antiaging, neuroprotective, hepatoprotective, cardioprotective and anticancer effects. However, the ability of SAL to regulate the osteo/odontogenic differentiation of hDPSCs remains to be elucidated. In the present study, the effect of SAL on the proliferation and osteogenic/odontogenic differentiation of human dental pulp stem cells (hDPSCs) was investigated. This was achieved by performing CCK-8 ARS staining assay, reverse transcription-quantitative PCR to detect mRNA of ALP, OSX, RUNX2, OCN, DSPP and BSP, western blotting to detect the protein of MAPK, Smad1/5/8, OSX, RUNX2, BSP and GAPDH and immunofluorescence assays to detect DSPP. The results indicated that SAL promoted the cell viability and the osteogenic/odontogenic differentiation of hDPSCs whilst increasing the expression of genes associated with osteogenic/odontogenic differentiation by ARS staining assay. In addition, SAL promoted osteogenic and odontogenic differentiation by activating the phosphorylation of Smad1/5/8. Collectively, these findings suggest that SAL promoted the osteogenic and odontogenic differentiation of hDPSCs activating the BMP signaling pathway.

Salidroside promotes human periodontal ligament cell proliferation and osteocalcin secretion via ERK1/2 and PI3K/Akt signaling pathways.

Salidroside modulates cell proliferation and serves as an anti-inflammatory and anti-apoptotic agent with efficacy against various diseases. The objective of the present study was to investigate the efficacy of salidroside in enhancing the proliferation of human periodontal ligament cells (hPDLCs). hPDLCs were isolated and the effects of salidroside on cell viability, soluble osteocalcin levels and activation of proliferation-associated signaling pathways were determined using a CCK-8 assay, ELISA and Western blotting, respectively. The results indicated that salidroside induced proliferation of hPDLCs, increased secretion of soluble osteocalcin and enhanced activation of extracellular signal-regulated kinase (ERK)1/2 and phosphoinositide-3 kinase (PI3K)/Akt signaling pathways. These factors were upregulated by salidroside in a dose-dependent manner. The results of the present study suggested that salidroside mediated hPDLC proliferation via the ERK1/2 and PI3K/Akt signaling pathways, as well as osteocalcin secretion. Salidroside may therefore be used as a novel therapeutic agent in the treatment of the tooth-supporting apparatus, progressive tooth destruction or periodontitis.

[EXPERIMENTAL STUDIES ON EFFECTS OF SALIDROSIDE/COLLAGEN/ POLYCAPROLACTONE NERVE GUIDE CONDUITS FOR REPAIRING SCIATIC NERVE DEFECT IN RATS].

OBJECTIVE: To fabricate salidroside/collagen/polycaprolactone (PCL) nerve conduit composite and to investigate the effect of composite nerve conduits for repairing sciatic nerve defect. METHODS: The salidroside microspheres were prepared by W/O/W method, and the sustained release rate of microspheres was detected. The microspheres containing 10, 20, and 40 µg salidroside were mixed with collagen to prepare the nerve conduit core layer by freeze-drying method. The shell layer of collagen/PCL scaffold material was fabricated by electrospinning technology. The genipin cross-linked salidroside/collagen/PCL nerve conduit composite was prepared. The structure of nerve conduit was observed before and after cross-linked by scanning electron microscope. Thirty-eight Wistar rats were used to make the right sciatic nerve defect model of 15 mm in length, and randomly divided into groups A, B, C, D (n=9), and group E (n=2), then defect was repaired with the collagen/PCL conduit in group A, autologous nerve in group E, the 10, 20, and 40 µg/mL salidroside/collagen/PCL conduit in groups B, C, and D, respectively. The survival of rats was observed. The sciatic functional index (SFI) was evaluated at 1, 3, and 6 months after operation. At 6 months, the tissue of defect area was harvested for the general, electrophysiology, histological, and immunohistochemical[S-100 and peripheral myelin protein 0(P0)] staining observations. RESULTS: Salidroside microspheres showed burst release at 3 days, and then it tended to be stable at 13 days and lasted for 16 days, with a cumulative release rate of 76.59%. SEM showed that the disordered fiber of nerve conduit shell layer after crosslinking became conglutination, shrinkage, and density, and had void. The channels of core layer were clearly visible before and after crosslinking. The rats had no infection or death after operation. The SFI of group E was significantly higher than that of groups A, B, C, and D at 1, 3, and 6 months (P<0.05); it was significantly higher in groups B, C, and D than group A (P<0.05), but no significant difference was found among groups B, C, and D at 1 month (P>0.05); there was no significant difference in SFI among groups A, B, C, and D at 3 months (P>0.05); SFI was significantly higher in group C than groups A, B, and D and in groups A and B than group D (P<0.05), but no significant difference between groups A and B (P>0.05) at 6 months. In addition, no significant difference was shown among different time points in the other groups (P>0.05) except groups C and E at 1, 3, and 6 months (P<0.05). The general observation showed that good connection with the thick nerve in groups B and C, and connection with the fine nerves in groups A and D. The conduit materials obviously degraded. Nerve electrophysiological examination showed that the latency/conduction velocity of groups C and E were significantly lower than those of groups A, B, and D (P<0.05), but difference was not significant between groups C and E, and among groups A, B, and D (P>0.05). The histological observation showed that the nerve fiber tissue of groups B, C, and E was obviously more than that of groups A and D, and group C was similar to group E in the nerve fiber arrangement, and the core layer material of each group was completely degraded. Immunohistochemical staining showed that S-100 and P0 proteins expressed in all groups; and the expression level of groups B, C, and E was significantly higher than that of groups A and D, and gradually increased (P<0.05); difference in S-100 expression level was not significant between groups A and D (P>0.05), and P0 expression level of group A was significantly lower than that of group D (P<0.05). CONCLUSIONS: Salidroside/collagen/PCL nerve conduit can promote sciatic nerve defect repair.

Amphiphilic chitosan derivatives-based liposomes: synthesis, development, and properties as a carrier for sustained release of salidroside.

A novel amphiphilic chitosan derivative of N,N-dimethylhexadecyl carboxymethyl chitosan (DCMCs) was synthesized. The structure of DCMCs was confirmed via FT-IR and (1)H NMR, and the critical micelle concentration (CMC) was investigated by fluorescence spectroscopy. The results indicated that DCMCs has hydrophilic carboxyl and hydrophobic methylene groups and the CMC value was 23.00 mg·L(-1). The polymeric liposomes (DCMCs/cholesterol liposomes, DC-Ls) were developed, and its properties were evaluated. The DC-Ls exhibited multilamellar spheres with positive charge (+73.30 mV), narrow size distribution (PDI = 0.277), and good crystal properties. Salidroside was first to encapsulate into DC-Ls. Compared with traditional liposomes (phosphatidylcholine/cholesterol liposome, PC-Ls), DC-Ls showed higher encapsulation efficiency (82.46%) and slower sustained release rate. The in vitro salidroside release from DC-Ls was governed by two distinct stages (i.e., burst release and sustained release) and was dependent on the pH of the release medium. The case II transport and case I Fichian diffusion were the main release mechanisms for the entire release procedure. These results indicated that DC-Ls may be a potential carrier system for the production of functional foods that contain salidroside or other bioactive food ingredients.

Salidroside liposome formulation enhances the activity of dendritic cells and immune responses.

Salidroside, the important composition, of Rhodiola rosea L. has been reported to have various pharmacological properties. Liposome is known to be effective as drug carriers and immune adjuvant. Therefore, the aim of this study is to investigate immunological adjuvant activity of salidroside liposome. Here we reported the preparation, the effect on DCs in vitro and the immune response in vivo. The immunological adjuvant activity of salidroside liposome formulation was compared with that of salidroside and liposome. The result showed that salidroside liposome formulation not only could promote the maturation of DCs, the stimulation of DCs on MLR proliferation and the antigen presenting ability, but also induced the sustained cellular immune and humoral immune response. Overall, the results showed that salidroside liposome formulation had the potential to act as effective sustained release vaccine delivery systems.