Naringin Inhibits Apoptosis Induced by Cyclic Stretch in Rat Annular Cells and Partially Attenuates Disc Degeneration by Inhibiting the ROS/NF-κB Pathway.

Oxidative stress and apoptosis play important roles in the pathogenesis of various degenerative diseases. Previous studies have shown that naringin can exert therapeutic effects in multiple degenerative diseases by resisting oxidative stress and inhibiting apoptosis. Although naringin is effective in treating degenerative disc disease, the underlying mechanism remains unclear. This study is aimed at investigating the effects of naringin on oxidative stress, apoptosis, and intervertebral disc degeneration (IVDD) induced by cyclic stretch and the underlying mechanisms in vitro and in vivo. Abnormal cyclic stretch was applied to rat annulus fibrosus cells, which were then treated with naringin, to observe the effects of naringin on apoptosis, oxidative stress, mitochondrial function, and the nuclear factor- (NF-) κB signaling pathway. Subsequently, a rat model of IVDD induced by dynamic and static imbalance was established to evaluate the effects of naringin on the degree of degeneration (using imaging and histology), apoptosis, and oxidative stress in the serum and the intervertebral disc. Naringin inhibited the cyclic stretch-induced apoptosis of annulus fibrosus cells, reduced oxidative stress, improved mitochondrial function, enhanced the antioxidant capacity, and suppressed the activation of the NF-κB signaling pathway. Additionally, it reduced the degree of IVDD (evaluated using magnetic resonance imaging) and the level of oxidative stress and inhibited apoptosis and p-P65 expression in the intervertebral discs of rats. Thus, naringin can inhibit cyclic stretch-induced apoptosis and delay IVDD, and the underlying mechanism may be related to the inhibition of oxidative stress and activation of the NF-κB signaling pathway. Naringin may be an effective drug for treating degenerative disc disease.

TOB1-AS1 suppresses non-small cell lung cancer cell migration and invasion through a ceRNA network.

Non-small cell lung cancer (NSCLC) is the leading cause of lung cancer-associated mortality. Recent studies revealed that long non-coding (lnc)RNAs have crucial roles in human cancers. The present study was the first, to the best of our knowledge, to indicate that the lncRNA transducer of ERBB2, 1-antisense 1 (TOB1-AS1) acts as a tumor suppressor in NSCLC. Knockdown of TOB1-AS1 significantly induced NSCLC cell migration, invasion and proliferation. It was also demonstrated that the higher expression of TOB1-AS1 in NSCLC samples was associated with longer overall survival time. Furthermore, a TOB1-AS1-mediated competing endogenous RNA network in NSCLC was constructed, including Homo sapiens (hsa)-microRNA (miR)-27a-3p, hsa-miR-23a-3p, hsa-miR-23b-3p, hsa-miR-27b-3p, hsa-miR-23c, dynein cytoplasmic 2 light intermediate chain 1, E4F transcription factor 1, TSPY-like 4, component of oligomeric Golgi complex 7, inositol hexakisphosphate kinase 2 and deltex E3 ubiquitin ligase 3. Of note, dysregulation of targets of TOB1-AS1 was associated with the prognosis of NSCLC patients. The present study suggested that TOB1-AS1 may serve as a novel biomarker for NSCLC.

Naringin inhibits vascular endothelial cell apoptosis via endoplasmic reticulum stress­ and mitochondrial­mediated pathways and promotes intraosseous angiogenesis in ovariectomized rats.

In this study, to investigate the effects of naringin on vascular endothelial cell (VEC) function, proliferation, apoptosis, and angiogenesis, rat VECs were cultured in vitro and randomly divided into four groups: control, serum­starved, low­concentration naringin treatment, and high­concentration naringin treatment. MTT assay was used to detect cell proliferation while Hoechst 33258 staining and flow cytometry were used to detect apoptosis. Changes in the expression of apoptosis­associated proteins [GRP78, CHOP, caspase­12, and cytochrome c (Cyt.c)] were detected using western blotting. JC­1 staining was employed to detect changes in mitochondrial membrane potential. Intracellular caspase­3, ­8, and ­9 activity was determined by spectrophotometry. ELISA was used to detect endothelin (ET), and a Griess assay was used to detect changes in the expression of nitric oxide (NO) in culture medium. The study further divided an ovariectomized (OVX) rat model of osteoporosis randomly into four groups: OVX, sham­operated, low­concentration naringin treatment (100 mg/kg), and high­concentration naringin treatment (200 mg/kg). After 3 months of treatment, changes in serum ET and NO expression, bone mineral density (BMD), and microvessel density of the distal femur (using CD34 labeling of VECs) were determined. At each concentration, naringin promoted VEC proliferation in a time­ and dose­dependent manner. Naringin also significantly reduced serum starvation­induced apoptosis in endothelial cells, inhibited the expression of GRP78, CHOP, caspase­12, and Cyt.c proteins, and reduced mitochondrial membrane potential as well as reduced the activities of caspase­3 and ­9. Furthermore, naringin suppressed ET in vitro and in vivo while enhancing NO synthesis. Distal femoral microvascular density assessment showed that the naringin treatment groups had a significantly higher number of microvessels than the OVX group, and that microvascular density was positively correlated with BMD. In summary, naringin inhibits apoptosis in VECs by blocking the endoplasmic reticulum (ER) stress­ and mitochondrial­mediated pathways. Naringin also regulates endothelial cell function and promotes angiogenesis to exert its anti­osteoporotic effect.

Induction of G2/M phase cell cycle arrest and apoptosis by ginsenoside Rf in human osteosarcoma MG­63 cells through the mitochondrial pathway.

Ginsenosides, extracted from the traditional Chinese herb ginseng, are a series of novel natural anticancer products known for their favorable safety and efficacy profiles. The present study aimed to investigate the cytotoxicity of ginsenoside Rf to human osteosarcoma cells and to explore the anticancer molecular mechanisms of ginsenoside Rf. Five human osteosarcoma cell lines (MG-63, OS732, U-2OS, HOS and SAOS-2) were employed to investigate the cytotoxicity of ginsenoside Rf by MTT and colony forming assays. After treatment with ginsenoside Rf, MG-63 cells which were the most sensitive to ginsenoside Rf, were subjected to flow cytometry to detect cell cycle distribution and apoptosis, and nuclear morphological changes were visualized by Hoechst 33258 staining. Caspase-3, -8 and -9 activities were also evaluated. The expression of cell cycle markers including cyclin B1 and Cdk1 was detected by RT-PCR and western blotting. The expression of apoptotic genes Bcl-2 and Bax and the release of cytochrome c were also examined by western blotting. Change in the mitochondrial membrane potential was observed by JC-1 staining in situ. Our results demonstrated that the cytotoxicity of ginsenoside Rf to these human osteosarcoma cell lines was dose-dependent, and the MG-63 cells were the most sensitive to exposure to ginsenoside Rf. Additionally, ginsenoside Rf induced G2/M phase cell cycle arrest and apoptosis in MG-63 cells. Furthermore, we observed upregulation of Bax and downregulation of Bcl-2, Cdk1 and cyclin B1, the activation of caspase-3 and -9 and the release of cytochrome c in MG-63 cells following treatment with ginsenoside Rf. Our findings demonstrated that ginsenoside Rf induces G2/M phase cell cycle arrest and apoptosis in human osteosarcoma MG-63 cells through the mitochondrial pathway, suggesting that ginsenoside Rf, as an effective natural product, may have a therapeutic effect on human osteosarcoma.