Adapalene Inhibits Prostate Cancer Cell Proliferation In Vitro and In Vivo by Inducing DNA Damage, S-phase Cell Cycle Arrest, and Apoptosis.

Aims: Prostate cancer is a well-known aggressive malignant tumor in men with a high metastasis rate and poor prognosis. Adapalene (ADA) is a third-generation synthetic retinoid with anticancer properties. We investigated the anti-tumor activity and molecular mechanisms of ADA in the RM-1 prostate cancer cell line in vivo and in vitro. Methods: The effects of ADA on cell proliferation were estimated using the CCK-8 and colony formation assays. The wound-healing assay and the Transwell assay were employed to examine the migratory capacity and invasiveness of the cells. Flow cytometry was utilized to evaluate the cell cycle and apoptosis, and Western blotting analysis was used to assess the expression of the associated proteins. Micro-CT, histomorphological, and immunohistochemical staining were used to assess the effects of ADA on bone tissue structure and tumor growth in a mouse model of prostate cancer bone metastasis. Result: ADA dramatically inhibited cell proliferation, migration, invasiveness, and induced S-phase arrest and apoptosis. ADA also regulated the expression of S-phase associated proteins and elevated the levels of DNA damage markers, p53, and p21 after ADA treatment, suggesting that the anti-tumor effect of ADA manifests through the DNA damage/p53 pathway. Furthermore, we observed that ADA could effectively inhibited tumor growth and bone destruction in mice. Conclusion: ADA inhibited prostate cancer cell proliferation, elicited apoptosis, and arrested the cell cycle in the S-phase. ADA also slowed the rate of tumor growth and bone destruction in vitro. Overall, our results suggest that ADA may be a potential treatment against prostate cancer.

Total flavonoids of hawthorn leaves promote motor function recovery via inhibition of apoptosis after spinal cord injury.

Flavonoids have been reported to have therapeutic potential for spinal cord injury. Hawthorn leaves have abundant content and species of total flavonoids, and studies of the effects of the total flavonoids of hawthorn leaves on spinal cord injury have not been published in or outside China. Therefore, Sprague-Dawley rats were used to establish a spinal cord injury model by Allen's method. Rats were intraperitoneally injected with 0.2 mL of different concentrations of total flavonoids of hawthorn leaves (5, 10, and 20 mg/kg) after spinal cord injury. Injections were administered once every 6 hours, three times a day, for 14 days. After treatment with various concentrations of total flavonoids of hawthorn leaves, the Basso, Beattie, and Bresnahan scores and histological staining indicated decreases in the lesion cavity and number of apoptotic cells of the injured spinal cord tissue; the morphological arrangement of the myelin sheath and nerve cells tended to be regular; and the Nissl bodies in neurons increased. The Basso, Beattie, and Bresnahan scores of treated spinal cord injury rats were increased. Western blot assays showed that the expression levels of pro-apoptotic Bax and cleaved caspase-3 were decreased, but the expression level of the anti-apoptotic Bcl-2 protein was increased. The improvement of the above physiological indicators showed a dose-dependent relationship with the concentration of total flavonoids of hawthorn leaves. The above findings confirm that total flavonoids of hawthorn leaves can reduce apoptosis and exert neuroprotective effects to promote the recovery of the motor function of rats with spinal cord injury. This study was approved by the Ethics Committee of the Guangxi Medical University of China (approval No. 201810042) in October 2018.

Monocrotaline Suppresses RANKL-Induced Osteoclastogenesis In Vitro and Prevents LPS-Induced Bone Loss In Vivo.

BACKGROUND/AIMS: Extensive osteoclast formation plays a critical role in bone diseases, including rheumatoid arthritis, periodontitis and the aseptic loosening of orthopedic implants. Thus, identification of agents that can suppress osteoclast formation and bone resorption is important for the treatment of these diseases. Monocrotaline (Mon), the major bioactive component of crotalaria sessiliflora has been investigated for its anti-cancer activities. However, the effect of Mon on osteoclast formation and osteolysis is not known. METHODS: The bone marrow macrophages (BMMs) were cultured with M-CSF and RANKL followed by Mon treatment. Then the effects of Mon on osteoclast differentiation were evaluated by counting TRAP (+) multinucleated cells. Moreover, effects of Mon on hydroxyapatite resorption activity of mature osteoclast were studied through resorption areas measurement. The involved potential signaling pathways were analyzed by performed Western blotting and quantitative real-time PCR examination. Further, we established a mouse calvarial osteolysis model to measure the osteolysis suppressing effect of Mon in vivo. RESULTS: In this study, we show that Mon can inhibit RANKL-induced osteoclast formation and function in a dose-dependent manner. Mon inhibits the expression of osteoclast marker genes such as tartrate-resistant acid phosphatase (TRAP) and cathepsin K. Furthermore, Mon inhibits RANKL-induced the activation of p38 and JNK. Consistent with in vitro results, Mon exhibits protective effects in an in vivo mouse model of LPS-induced calvarial osteolysis. CONCLUSION: Taken together our data demonstrate that Mon may be a potential prophylactic anti-osteoclastic agent for the treatment of osteolytic diseases caused by excessive osteoclast formation and function.

Artesunate inhibits RANKL-induced osteoclastogenesis and bone resorption in vitro and prevents LPS-induced bone loss in vivo.

Osteoclasts are multinuclear giant cells responsible for bone resorption in lytic bone diseases such as osteoporosis, arthritis, periodontitis, and bone tumors. Due to the severe side-effects caused by the currently available drugs, a continuous search for novel bone-protective therapies is essential. Artesunate (Art), the water-soluble derivative of artemisinin has been investigated owing to its anti-malarial properties. However, its effects in osteoclastogenesis have not yet been reported. In this study, Art was shown to inhibit the nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis, the mRNA expression of osteoclastic-specific genes, and resorption pit formation in a dose-dependent manner in primary bone marrow-derived macrophages cells (BMMs). Furthermore, Art markedly blocked the RANKL-induced osteoclastogenesis by attenuating the degradation of IκB and phosphorylation of NF-κB p65. Consistent with the in vitro results, Art inhibited lipopolysaccharide (LPS)-induced bone resorption by suppressing the osteoclastogenesis. Together our data demonstrated that Art inhibits RANKL-induced osteoclastogenesis by suppressing the NF-κB signaling pathway and that it is a promising agent for the treatment of osteolytic diseases.

Polygonatum sibiricum polysaccharide inhibits osteoporosis by promoting osteoblast formation and blocking osteoclastogenesis through Wnt/ß-catenin signalling pathway.

Bone homeostasis is maintained by a balance between bone formation by osteoblasts and bone resorption by osteoclasts. Osteoporosis occurs when osteoclast activity surpasses osteoblast activity. Our previous studies showed the plant-derived natural polysaccharide (Polygonatum sibiricum polysaccharide or PSP) had significant anti-ovariectomy (OVX)-induced osteoporosis effects in vivo, but the mechanisms of PSP's anti-osteoporosis effect remains unclear. In this study, we assessed PSP's effect on the generation of osteoblast and osteoclast in vitro. This study showed that PSP promoted the osteogenic differentiation of mouse bone marrow stromal cells (BMSCs) without affecting BMPs signaling pathway. This effect was due to the increased nuclear accumulation of ß-catenin, resulting in a higher expression of osteoblast-related genes. Furthermore, the study showed PSP could inhibit the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis and exert prophylatic protection against LPS-induced osteolysis in vivo. This effect was also related to the increased nuclear accumulation of ß-catenin, resulting in the decreased expression of osteoclast-related genes. In conclusion, our results showed that PSP effectively promoted the osteogenic differentiation of mouse BMSCs and suppressed osteoclastogenesis; therefore, it could be used to treat osteoporosis.

The Role of 6-Gingerol on Inhibiting Amyloid ß Protein-Induced Apoptosis in PC12 Cells.

Our previous study suggests that ginger root extract can reverse behavioral dysfunction and prevent Alzheimer's disease (AD)-like symptoms induced by the amyloid-ß protein (Aß) in a rat model. 6-Gingerol is the major gingerol in ginger rhizomes, but its effect on the treatment of AD remains unclear. In this study, we aimed to determine if 6-gingerol had a protective effect on Aß1-42-induced damage and apoptotic death in rat pheochromocytoma cells (PC12 cells) and to investigate the underlying mechanisms by which 6-gingerol may exert its neuroprotective effects. Our results indicated that pre-treatment with 6-gingerol significantly increased cell viability and reduced cell apoptosis in Aß1-42-treated cells. Moreover, 6-gingerol pretreatment markedly reduced the level of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), the production of nitric oxide (NO), and the leakage of lactate dehydrogenase (LDH) and increased superoxide dismutase (SOD) activity compared with the Aß1-42 treatment group. In addition, 6-gingerol pretreatment also significantly enhanced the protein levels of phosphorylated Akt (p-Akt) and glycogen synthase kinase-3ß (p-GSK-3ß). Overall, these results indicate that 6-gingerol exhibited protective effects on apoptosis induced by Aß1-42 in cultured PC12 cells by reducing oxidative stress and inflammatory responses, suppressing the activation of GSK-3ß and enhancing the activation of Akt, thereby exerting neuroprotective effects. Therefore, 6-gingerol may be useful in the prevention and/or treatment of AD.

Systematic review and meta-analysis of the bone protective effect of phytoestrogens on osteoporosis in ovariectomized rats.

Phytoestrogens are candidate drugs for the treatment of osteoporosis. Many experiments have been designed to investigate the preventive effects of phytoestrogens for osteoporosis; however, it is easy for a single dissenting result from animal experiments to mislead clinical investigations. Herein, we use meta-analysis to assess the evidence for a protective effect of phytoestrogens on ovariectomized rat models of osteopenia. With respect to osteoporosis, PubMed and Web of Science were searched from January 2000 to March 2013 for relevant studies of phytoestrogens in ovariectomized rats. Two reviewers independently selected and assessed the studies. Data were aggregated using a random effects model. Meta-analysis revealed that the phytoestrogen treatment group demonstrated a significantly higher femur bone mineral density and trabecular bone and lower bone turnover markers (serum alkaline phosphatase and serum osteocalcin) compared with the control ovariectomized group, thus showing a bone protective effect of phytoestrogens in ovariectomized rats. Subsequent sensitivity analyses indicated that the effect of phytoestrogens on serum alkaline phosphatase and serum osteocalcin are not robust. Despite the high heterogeneity in the systematic review of animal experiments, the present results indicated that phytoestrogens may offer the most potential for the prevention of bone loss by reducing the expected loss of trabecular bone and bone mineral density. Their effects are likely due to inhibition of bone resorption, but their benefits on bone formation are still unclear. Further studies are needed to assess the effect of phytoestrogens on bone formation and the efficacy and safety of individual phytoestrogens.

Protective effects of ginger root extract on Alzheimer disease-induced behavioral dysfunction in rats.

The aim of this study was to assess the ability of a traditional Chinese medicinal ginger root extract (GRE) to prevent behavioral dysfunction in the Alzheimer disease (AD) rat model. Rat AD models were established by an operation (OP) in which rats were treated with a one-time intra-cerebroventricuIar injection of amyloid ß-protein (Aß) and continuous gavage of aluminum chloride every day for 4 weeks. GRE was administered intra-gastrically to rats. After 35 days, learning and memory were assessed in all of the rats. Brain sections were processed for immunohistochemistry and Hematoxylin & Eosin (H&E) and Nissl staining. The latency to show significant memory deficits was shorter in the group that received OP with a high dose of GRE (HG)(OP+HG) than in the groups that received OP with a low or moderate dose of GRE (LG, MG)(OP+LG, OP+MG) (p<0.05). The expression of superoxide dismutase (SOD) and catalase (CAT) in the OP+MG and OP+LG groups was up-regulated compared to the OP+HG groups (p<0.05). The rats in the OP+HG groups had lower levels of nuclear factor-κB (NF-κB), interleukin-1ß (IL-1ß), and malondialdehyde (MDA) expression than the rats in the OP+MG and OP+LG groups (p<0.05). This experiment demonstrates that the administration of GRE reverses behavioral dysfunction and prevents AD-like symptoms in our rat model.

Protective effects of Polygonatum sibiricum polysaccharide on ovariectomy-induced bone loss in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: To assess the ability of traditional Chinese medicine Polygonatum sibiricum polysaccharide to prevent bone loss in the ovariectomized rat. MATERIALS AND METHODS: PSP was administered intragastrically to the rats. After 35 days, the total body bone mineral density (BMD) was assessed in all of the rats. All sections were processed for immunohistochemistry and hematoxylin-eosin staining (H.E.). RESULTS: BMD was lower in the ovariectomized group (OVX, 0.163 g/cm(2)), the group that received a moderate dose of PSP on OVX animals (OVX+MP, 0.163 g/cm(2)) and the group that received a low dose of PSP on OVX animals (OVX+LP, 0.162 g/cm(2)) than in the sham-operated group (SHAM, 0.180 g/cm(2)), the OVX+E(2) group (OVX+E(2), 0.176 g/cm(2)) and the group that received a high dose of PSP on OVX animals (OVX+HP, 0.174 g/cm(2)) (P<0.05). Clear arrangements of bone trabeculae were observed in the OVX+E(2) and OVX+HP. The expression of bone morphogenetic proteins (BMP) and basic fibroblast growth factor (bFGF) in the OVX, OVX+MP and OVX+LP was down regulated compared to the SHAM, OVX+E(2) and OVX+HP (P<0.05). The rats in the OVX+E(2) and OVX+HP had lower levels of bone Gla protein (BGP), bone alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRAP) and tumor necrosis factor α(TNF-α) expression than the rats in the OVX, OVX+MP and OVX+LP (P<0.05). CONCLUSION: This experiment demonstrates that the administration of PSP to ovariectomized rats reverses bone loss and prevents osteoporosis.