Paeoniflorin inhibits nucleus pulposus cell apoptosis by regulating the expression of Bcl-2 family proteins and caspase-9 in a rabbit model of intervertebral disc degeneration

Synthesis and Biological Evaluation of Indole-2-Carboxamides with Potent Apoptotic Antiproliferative Activity as EGFR/CDK2 Dual Inhibitors

The apoptotic antiproliferative actions of our previously reported CB1 allosteric modulators 5-chlorobenzofuran-2-carboxamide derivatives VIIa–j prompted us to develop and synthesise a novel series of indole-2-carboxamide derivatives 5a–k, 6a–c, and 7. Different spectroscopic methods of analysis were used to validate the novel compounds. Using the MTT assay method, the novel compounds were examined for antiproliferative activity against four distinct cancer cell lines. Compounds 5a–k, 6a–c, and 7 demonstrated greater antiproliferative activity against the breast cancer cell line (MCF-7) than other tested cancer cell lines, and 5a–k (which contain the phenethyl moiety in their backbone structure) demonstrated greater potency than 6a–c and 7, indicating the importance of the phenethyl moiety for antiproliferative action. Compared to reference doxorubicin (GI₅₀ = 1.10 µM), compounds 5d, 5e, 5h, 5i, 5j, and 5k were the most effective of the synthesised derivatives, with GI₅₀ ranging from 0.95 µM to 1.50 µM. Compounds 5d, 5e, 5h, 5i, 5j, and 5k were tested for their inhibitory impact on EGFR and CDK2, and the results indicated that the compounds tested had strong antiproliferative activity and are effective at suppressing both CDK2 and EGFR. Moreover, the studied compounds induced apoptosis with high potency, as evidenced by their effects on apoptotic markers such as Caspases 3, 8, 9, Cytochrome C, Bax, Bcl2, and p53.

Role of Caspase Family in Intervertebral Disc Degeneration and Its Therapeutic Prospects

Intervertebral disc degeneration (IVDD) is a common musculoskeletal degenerative disease worldwide, of which the main clinical manifestation is low back pain (LBP); approximately, 80% of people suffer from it in their lifetime. Currently, the pathogenesis of IVDD is unclear, and modern treatments can only alleviate its symptoms but cannot inhibit or reverse its progression. However, in recent years, targeted therapy has led to new therapeutic strategies. Cysteine-containing aspartate proteolytic enzymes (caspases) are a family of proteases present in the cytoplasm. They are evolutionarily conserved and are involved in cell growth, differentiation, and apoptotic death of eukaryotic cells. In recent years, it has been confirmed to be involved in the pathogenesis of various diseases, mainly by regulating cell apoptosis and inflammatory response. With continuous research on the pathogenesis and pathological process of IVDD, an increasing number of studies have shown that caspases are closely related to the IVDD process, especially in the intervertebral disc (IVD) cell apoptosis and inflammatory response. Therefore, herein we study the role of caspases in IVDD with respect to the structure of caspases and the related signaling pathways involved. This would help explore the strategy of regulating the activity of the caspases involved and develop caspase inhibitors to prevent and treat IVDD. The aim of this review was to identify the caspases involved in IVDD which could be potential targets for the treatment of IVDD.

Causes of and Molecular Targets for the Treatment of Intervertebral Disc Degeneration: A Review

Intervertebral disc degeneration (IVDD) is a pathological condition that can lead to intractable back pain or secondary neurological deficits. There is no fundamental cure for this condition, and current treatments focus on alleviating symptoms indirectly. Numerous studies have been performed to date, and the major strategy for all treatments of IVDD is to prevent cell loss due to programmed or regulated cell death. Accumulating evidence suggests that several types of cell death other than apoptosis, including necroptosis, pyroptosis, and ferroptosis, are also involved in IVDD. In this study, we discuss the molecular pathway of each type of cell death and review the literature that has identified their role in IVDD. We also summarize the recent advances in targeted therapy at the RNA level, including RNA modulations through RNA interference and regulation of non-coding RNAs, for preventing cell death and subsequent IVDD. Therefore, we review the causes and possible therapeutic targets for RNA intervention and discuss the future direction of this research field.

Innovative Biological Treatment Methods for Degenerative Disc Disease

Low back pain is the leading cause of work absences and years lived with disability, and it is often associated with degenerative disc disease. In recent years, biological treatment approaches such as the use of growth factors, cell injections, annulus fibrosus (AF) repair, nucleus pulposus replacement, and tissue-engineered discs have been explored as means for preventing or reversing degenerative disc disease. Both animal and clinical studies have shown promising results for cell-based therapy on the grounds of its regenerative potential. Clinical data also indicate that stem cell injection is safe when appropriately performed, albeit its long-term safety and efficacy are yet to be explored. Numerous challenges also remain to be overcome, such as isolating, differentiating, and preconditioning the disc cells, as well as managing the nutrient-deficient and oxygen-deficient micromilieu of the intervertebral disc (IVD). AF repair methods including devices used in clinical trials have shown success in decreasing reherniation rates and improving overall clinical outcomes. In addition, recent studies that combined AF repair and nucleus pulposus replacement have shown improved biomechanical stability in IVDs after the combined treatment. Tissue-engineered IVDs for total disc replacement are still being developed, and future studies are necessary to overcome the challenges in their delivery, efficacy, and safety.

Evaluation of Tissue Engineering Approaches for Intervertebral Disc Regeneration in Relevant Animal Models

Translation of tissue engineering strategies for the regeneration of intervertebral disc (IVD) requires a strong understanding of pathophysiology through the relevant animal model. There is no relevant animal model due to differences in disc anatomy, cellular composition, extracellular matrix components, disc physiology, and mechanical strength from humans. However, available animal models if used correctly could provide clinically relevant information for the translation into humans. In this review, we have investigated different types of strategies for the development of clinically relevant animal models to study biomaterials, cells, biomolecular or their combination in developing tissue engineering-based treatment strategies. Tissue engineering strategies that utilize various animal models for IVD regeneration are summarized and outcomes have been discussed. The understanding of animal models for the validation of regenerative approaches is employed to understand and treat the pathophysiology of degenerative disc disease (DDD) before proceeding for human trials. These animal models play an important role in building a therapeutic regime for IVD tissue regeneration, which can serve as a platform for clinical applications.

Expression of miR-195 and its target gene Bcl-2 in human intervertebral disc degeneration and their effects on nucleus pulposus cell apoptosis

Objective

To investigate the expression of miR-195 and its target gene Bcl-2 in intervertebral disc degeneration (IVDD) and its effect on nucleus pulposus (NP) cell apoptosis.

Methods

The expressions of miR-195 and Bcl-2 in NP tissues of IVDD patients were quantified by qRT-PCR and western blotting, respectively. NP cells were divided into blank group, TNF-α group, TNF-α + miR-NC group, TNF-α + siBcl-2 group, and TNF-α + miR-195 inhibitors + siBcl-2 group. Cell proliferation was detected by MTT assay, cell apoptosis evaluated by flow cytometry, and mitochondrial membrane potential (MMP) tested by JC-1 staining. Moreover, the function of miR-195 on IVDD in vivo was investigated using a puncture-induced IVDD rat model.

Results

IVDD patients had significantly increased miR-195 expression and decreased Bcl-2 protein expression in NP tissues. The expression of miR-195 was negatively correlated with the expression of Bcl-2 in IVDD patients. Dual-luciferase reporter gene assay indicated that Bcl-2 was a target gene of miR-195. In comparison with blank group, TNF-α group showed decreased cell proliferation and MMP, increased cell apoptosis, upregulated expression of miR-195, Bax, and cleaved caspase 3, and downregulated Bcl-2 protein, while these changes were attenuated by miR-195 inhibitors. Additionally, siBcl-2 can reverse the protective effect of miR-195 inhibitors on TNF-α-induced NP cells. Besides, inhibition of miR-195 alleviated IVDD degeneration and NP cell apoptosis in the rat model.

Conclusion

MiR-195 was significantly upregulated in NP tissues of IVDD patients, and inhibition of miR-195 could protect human NP cells from TNF-α-induced apoptosis via upregulation of Bcl-2.

Protective effect of paeoniflorin on H2O2 induced Schwann cells injury based on network pharmacology and experimental validation

This study was to investigate the protective effect of paeoniflorin (PF) on hydrogen peroxide-induced injury. Firstly, "SMILES" of PF was searched in Pubchem and further was used for reverse molecular docking in Swiss Target Prediction database to obtain potential targets. Injury-related molecules were obtained from GeenCards database, and the predicted targets of PF for injury treatment were selected by Wayne diagram. For mechanism analysis, the protein-protein interactions were constructed by String, and the KEGG analysis was conducted in Webgestalt. Then, cell viability and cytotoxicity assay were established by CCK8 assay. Also, the experimental cells were allocated to control, model (200 μmol·L^-1 H₂O₂), SB203580 10 μmol·L^-1 (200 μmol·L^-1 H₂O₂+ SB203580 10 μmol·L^-1), PF 50 μmol·L^-1 (200 μmol·L^-1 H₂O₂+ PF 50 μmol·L^-1), and PF 100 μmol·L^-1 (200 μmol·L^-1 H₂O₂+ PF 100 μmol·L^-1) groups. We measured the intracellular ROS, Hoechst 33258 staining, cell apoptosis, the levels of Bcl-xl, Bcl-2, Caspase-3, Cleaved-caspase3, Cleaved-caspase7, TRPA1, TRPV1, and the phosphorylation expression of p38MAPK. There are 96 potential targets that may be associated with PF for injury treatment. Then, we chose the "Inflammatory mediator regulation of TRP channels" pathway for the experimental verification from the first 10 KEGG pathway. In experimental verification, H₂O₂ decreased the cell viability moderately (P < 0.05), and 100 μmol·L ^-1 PF increased the cell viability significantly (P < 0.05). Depending on the difference of intracellular ROS fluorescence intensity, PF inhibited H ₂O₂-induced reactive oxygen species production in Schwann cells. In Hoechst 33258 staining, PF reversed the condensed chromatin and apoptotic nuclei following H₂O₂ treatment. Moreover, Flow cytometry results showed that PF could substantially inhibit H₂O₂ induced apoptosis (P < 0.05). Pretreatment with PF obviously reduced the levels of Caspase3, Cleaved-caspase3, Cleaved-caspase7, TRPA1, TRPV1, and the phosphorylation expression of p38MAPK after H ₂O₂ treatment (P < 0.05), increased the levels of Bcl-2, and Bcl-xl ( P < 0.05). PF inhibited Schwann cell injury and apoptosis induced by hydrogen peroxide, which mechanism was linked to the inhibition of phosphorylation of p38MAPK.

Long non-coding RNA MT1DP interacts with miR-365 and induces apoptosis of nucleus pulposus cells by repressing NRF-2-induced anti-oxidation in lumbar disc herniation

Background

This study investigated the effects of the long non-coding (lnc) RNA MT1DP on the apoptosis of nucleus pulposus (NP) cells. The interactions between MT1DP and the microRNA miR-365, and its effects on the anti-oxidant activity of nuclear factor erythroid 2-related factor 2 (NRF-2) were investigated in lumbar disc herniation (LDH).

Methods

Human degenerative intervertebral disc NP tissues were obtained from 10 patients with LDH who underwent lumbar spine surgery. Normal intervertebral disc NP tissues were obtained from 10 patients with lumbar vertebrae fractures and used as negative controls (NCs).

Results

The gene expressions of MT1DP and miR-365 in human degenerative disc NP tissues and nucleus pulposus cells (NPCs) were significantly increased, while the level of NRF-2 was significantly decreased. Overexpression of MT1DP and miR-365 (MT1DP + miR-365) and inhibition of NRF-2 suppressed NP cell viability and induced apoptosis. MT1DP + miR-365 caused inflammation in NP cells by damaging the mitochondrial membrane. The combination of lnc-MT1DP and miR-365 reduced cell mitochondrial function and led to a decrease in the ability of cells to elimination reactive oxygen species (ROS).

Conclusions

The combination of lnc-MT1DP and miR-365 damaged the cell mitochondrial membrane, reduced mitochondrial function and the ability to eliminate ROS, increased cell apoptosis, and caused LDH.

LncRNA TUG1 promotes the intervertebral disc degeneration and nucleus pulposus cell apoptosis though modulating miR-26a/HMGB1 axis and regulating NF-κB activation

AIMS

This study was to investigate the effect of TUG1 on apoptosis and ECM degradation of human degenerative intervertebral disc nucleus pulposus cells (NPCs) and its mechanism.

METHODS

Human degenerative intervertebral disc NP tissues were obtained from 10 patients with lumbar disc herniation (LDH) who underwent lumbar spine surgery (IDD group), normal intervertebral disc NP tissues were obtained from 10 patients with lumbar vertebrae fractures (LVF group).

RESULTS

The expression of TUG1 and HMGB1 protein in human degenerative disc NP tissues and NPCs was significantly increased, while the level of miR-26a was significantly decreased. Overexpression of TUG1 inhibited the proliferation while promoted apoptosis and ECM degradation of human degenerative intervertebral disc NPCs. Simultaneously, the effect of TUG1 knockdown on NPCs was opposite. Interestingly, TUG1 acted as an endogenous sponge to down-regulate the expression of miR-26a in NPCs by direct binding to miR-26a. Overexpression of miR-26a reversed the effects of TUG1 overexpression on apoptosis and ECM degradation. Additionally, HMGB1 was a target gene of miR-26a. The increased expression of HMGB1 induced by TUG1 overexpression could be reversed by the introduction of miR-26a mimic. Overexpression of TUG1 significantly upregulated the expression of p65 in the nucleus, while overexpression of TUG1 partially abolished the inhibition of NF-κB by QNZ pretreatment.

CONCLUSION

TUG1 could promote the apoptosis and ECM degradation of degenerated intervertebral disc NPCs by regulating the miR-26a/HMGB1, which may be involved in the activation of NF-κB pathway.

miR-573 regulates cell proliferation and apoptosis by targeting Bax in nucleus pulposus cells

Background

MicroRNA (miRNA) plays a vital role in the pathogenesis of intervertebral disc degeneration (IDD). The expression and potential mechanism of miR-573 in human nucleus pulposus (NP) remains to be elucidated. In this study, we aimed to investigate the role of miR-573 in IDD.

Methods

Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis was applied to examine the expression of miR-573 and Bax in idiopathic scoliosis tissues and IDD tissues. Human NP cells were employed for analysis. Moreover, the proliferation and apoptosis of NP cells were detected using MTT and flow cytometry assay respectively. The expression levels of Bcl-2, cleaved caspase-3, cleaved caspase-9, caspase-3 and caspase-9 in degenerative NP cells were measured by Western blotting assay. Furthermore, a luciferase reporter assay was used to verify the relationship between miR-573 and Bax.

Results

The results revealed that the mRNA expression level of miR-573 was down-regulated whereas Bax was up-regulated notably in degenerative NP cells. In addition, overexpression of miR-573 increased cell viability remarkably, coupled with inhibition of cell apoptosis. The expression level of Bcl-2 was increased while cleaved caspase-3 and cleaved caspase-9 expression levels were decreased in miR-573 overexpression NP cells. Additionally, the bioinformatics analysis underscored that Bax was a direct target gene of miR-573.

Conclusion

These results suggest that overexpression of miR-573 inhibited NP cell apoptosis by down-regulating Bax, which proved to be a novel effective strategy for IDD therapies.

Neuroprotection by Paeoniflorin against Nuclear Factor Kappa B-Induced Neuroinflammation on Spinal Cord Injury

Background

Acute spinal cord injury (SCI) is one of the most common and devastating causes of sensory or motor dysfunction. Nuclear factor-kappa B(NF-κB)-mediated neuroinflammatory responses, in addition to nitric oxide (NO), are key regulatory pathways in SCI. Paeoniflorin (PF), a major active component extracted from Paeonia roots, has been suggested to exert neuroprotective effects in the central nervous system. However, whether PF could improve the motor function after SCI in vivo is still unclear.

Method

Immunohistochemical analysis, western blot, real-time quantitative PCR, immunofluorescence staining, and histopathological and behavioral evaluation were used to explore the effects of paeoniflorin after SCI for 14 days.

Results

In this study, PF treatment significantly inhibited NF-κB activation and downregulated the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2(COX-2), and Nogo-A. Comparing behavioral and histological changes in SCI and PF treatment groups, we found that PF treatment improved motor function recovery, attenuated the histopathological damage, and increased neuronal survival in the SCI model. PF treatment also reduced expression levels of Bax and c-caspase-3 and increased the expression level of Bcl-2 and cell viabilities. Upregulation of TNF-α, IL-6, and IL-1β after injury was also prevented by PF.

Conclusion

These results suggest that the neuroprotective effects of PF are related to the inhibition of the NF-κB signaling pathway. And PF may be a therapeutic strategy in spinal cord injury.

LncRNA HOTAIR suppresses TNF-α induced apoptosis of nucleus pulposus cells by regulating miR-34a/Bcl-2 axis

OBJECTIVE

The aim of this study was to investigate the regulation mechanism of HOTAIR on nucleus pulposus cell (NPC) apoptosis induced by inflammatory cytokines.

METHODS

QRT-PCR was performed to analyze the expression of HOTAIR and miR-34a. Safranin O staining and immunohistochemical staining were measured to identify NPCs. ELISA assay was used to detect TNF-α level. Apoptosis was detected with TUNEL assay. Western blotting was measured to analyze the expression of caspase-3, Bax and Bcl-2. TargetScan was used to predict potential targets of miR-34a.

RESULTS

HOTAIR was significantly low-expressed in degenerative nucleus pulposus (NP) tissues and cells of IDD patients, overexpressing HOTAIR obviously inhibited TNF-α level, NPCs apoptosis and the expression of caspase-3 and Bax, while promoted the expression of Bcl-2. MiR-34a was obviously expressed in degenerative NP tissues and cells of IDD patients. HOTAIR reduced miR-34a induced apoptosis. Apoptotic inhibition gene Bcl-2 is the target gene of miR-34a, and showed a negative relationship with miR-34a.

CONCLUSION

Our data suggest that lncRNA HOTAIR suppresses TNF-α induced NPCs apoptosis by regulating miR-34a/Bcl-2 axis in IDD patients.

Paeoniflorin inhibits IL-1β-induced MMP secretion via the NF-κB pathway in chondrocytes

Paeoniflorin serves important cellular roles, exerting anti-cancer, anti-inflammatory and anti-pulmonary fibrosis effects and possesses immune-modulatory properties. However, the exact role of paeoniflorin in the pathogenesis of osteoarthritis (OA) remains unclear. The aim of the present study was to investigate the effects of paeoniflorin on articular surfaces in vitro. Rat chondrocytes were cultured in vitro and an MTT assay was performed to assess chondrocyte survival. Following treatment with interleukin (IL)-1β and paeoniflorin, the production of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases-1 (TIMP-1) was examined using reverse transcription-quantitative polymerase chain reaction and western blotting. The interleukin (IL)-1β-induced nuclear factor (NF)-κB pathway activation was also investigated. The results demonstrated that paeoniflorin was able to downregulate the expression of MMP and increase the expression of TIMP-1ntmRNA and protein in IL-1β-induced rat chondrocytes. Furthermore, treating chondrocytes with paeoniflorin blocked the activation of NF-κB. These results suggest that paeoniflorin may serve am anti-catabolic role in the progression of OA and may be an effective preventative treatment for OA.

Protective effect and molecular mechanism of liquiritin on oxybuprocaine-induced apoptosis of human corneal endothelial cells

This study was designed to investigate the protective effect and possible molecular mechanism of liquiritin on oxybuprocaine-induced apoptosis of human corneal endothelial cells (HCECs). In this study, the effect of oxybuprocaine on the proliferation of HCEC-12 was detected using cell counting kit-8 (CCK-8). The inductive effect of oxybuprocaine on HCEC-12 apoptosis and protective effect of liquiritin against oxybuprocaine-induced HCEC-12 apoptosis were tested by Annexin V/propidium iodide (PI) staining and flow cytometry. The production of reactive oxygen species (ROS) was analyzed by 2,7-dichlorodi-hydrofluorescein diacetate (DCFH-DA) staining and fluorescent-activated cell sorting (FACS), and the expression of nuclear factor-κB (NF-κB) p65 and apoptosis-related proteins, caspase-3 and Bax, was determined by western blot analysis. Our results show that liquiritin resisted the inhibitory effect of oxybuprocaine on the proliferation of HCEC-12, and cell activity had the most significant increase in pretreatment with liquiritin group in the concentration of 8 mg/ml; compared with that in oxybuprocaine group. Apoptosis in pretreatment with liquiritin was distinctly decreased and liquiritin resisted the production of ROS in HCEC-12 induced by oxybuprocaine. Investigation of molecular mechanism revealed that the pretreatment with liquiritin and pyrrolidinedithiocarbamic acid (PDTC) obviously blocked the expression of NF-κB p65 in nuclear protein increased by oxybuprocaine and the expression levels of total proteins, caspase-3 and Bax.Moreover, tumor necrosis factor-α (TNF-α) blocked the inhibitory effect of liquiritin on the expression of NF-κB p65 in nuclear protein and total proteins, caspase-3 and Bax, thus obstructing the protective effect of liquiritin on corneal epithelial cells. The results of this study indicated that liquiritin reduces the expression of apoptosis protein and increases the expression of anti-apoptotic protein through inhibiting NF-κB signal pathway, thus resisting HCEC-12 apoptosis induced by oxybuprocaine.

Paeoniflorin inhibits IL-1β-induced chondrocyte apoptosis by regulating the Bax/Bcl-2/caspase-3 signaling pathway

Apoptosis serves a pivotal role in the pathogenesis of osteoarthritis (OA). Increasing evidence has demonstrated that paeoniflorin exerts key properties (including anticancer, anti-inflammation and neuroprotective) for clinical applications. However, the precise role of paeoniflorin in articular cartilage apoptosis remains unknown. The present study explored the effects and potential molecular mechanism of paeoniflorin on rat chondrocyte apoptosis. Rat articular chondrocytes were cultured in monolayers. The lactate dehydrogenase (LDH) release rate of cells was determined by an LDH release assay. Annexin V-fluorescein isothiocyanate and propidium iodide staining were performed to detect early and advanced apoptotic cells by flow cytometry. The activity of caspase-3 in chondrocytes was determined using a caspase-3 activity assay. The expression of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax) was examined by reverse transcription‑quantitative polymerase chain and western blotting. The present study also examined the protein kinase B (Akt) signaling pathway by western blotting. Treatment with 25 or 50 µM paeoniflorin markedly decreased the release of LDH and the ratio of apoptotic cells in interleukin (IL)-1β-induced rat chondrocytes. Paeoniflorin treatment decreased the mRNA and protein levels of Bax, and increased the level of Bcl-2. Paeoniflorin also reduced the activity of caspase-3 in chondrocytes. Furthermore, paeoniflorin was determined to regulate the Akt signaling pathway by increasing Akt phosphorylation. Therefore, paeoniflorin may exert its protective effect by inhibiting apoptosis in IL-1β-induced rat chondrocytes and thus, may be an effective agent in the prevention and treatment of OA.

Paeoniflorin reduces neomycin-induced ototoxicity in hair cells by suppression of reactive oxygen species generation and extracellularly regulated kinase signalization

The present study was designed to investigate the effect of paeoniflorin (PF) on neomycin-induced ototoxicity in hair cells (HCs). Here, we took advantage of C57BL/6 mice and cochlear explants culture to determine the role of PF in vivo and in vitro. We demonstrated that neomycin exposure induced severe hearing loss and HC damage, which was mediated by activated mitochondrial apoptosis pathway, promoted extracellular signal-regulated kinase (ERK) signaling as well as enhanced reactive oxygen species (ROS) generation in HCs. Interestingly, we found that PF pretreatment significantly alleviated neomycin-induced hearing loss, attenuated HC injury and decreased HC apoptosis caused by neomycin. Mechanistic studies revealed that PF could decrease cellular ROS levels, suppress the activation of ERK signaling and, subsequently, mitigate the imbalance of mitochondrial apoptotic pathway, thus protecting HCs from neomycin-induced apoptosis. This study indicates that PF may serve as an antioxidative and anti-apoptotic agent to prevent hearing loss caused by neomycin.

Cytotoxicity and Proapoptotic Effects of Allium atroviolaceum Flower Extract by Modulating Cell Cycle Arrest and Caspase-Dependent and p53-Independent Pathway in Breast Cancer Cell Lines

Breast cancer is the second leading cause of cancer death among women and despite significant advances in therapy, it remains a critical health problem worldwide. Allium atroviolaceum is an herbaceous plant, with limited information about the therapeutic capability. We aimed to study the anticancer effect of flower extract and the mechanisms of action in MCF-7 and MDA-MB-231. The extract inhibits the proliferation of the cells in a time- and dose-dependent manner. The underlying mechanism involved the stimulation of S and G2/M phase arrest in MCF-7 and S phase arrest in MDA-MB-231 associated with decreased level of Cdk1, in a p53-independent pathway. Furthermore, the extract induces apoptosis in both cell lines, as indicated by the percentage of sub-G0 population, the morphological changes observed by phase contrast and fluorescent microscopy, and increase in Annexin-V-positive cells. The apoptosis induction was related to downregulation of Bcl-2 and also likely to be caspase-dependent. Moreover, the combination of the extract and tamoxifen exhibits synergistic effect, suggesting that it can complement current chemotherapy. LC-MS analysis displayed 17 major compounds in the extract which might be responsible for the observed effects. Overall, this study demonstrates the potential applications of Allium atroviolaceum extract as an anticancer drug for breast cancer treatment.

Noninvasive cumulative axial load may induce intervertebral disc degeneration-A potential rabbit model

Intervertebral disc degeneration (IDD) is considered to be the main cause of many spinal disorders; however, its underlying pathophysiology is not clearly understood. Recent studies indicate that excessive mechanical loading may serve a major role in the initiation of IDD. The aim of the present study was to explore the effect of noninvasive cumulative axial loading on the intervertebral discs of the lumbar spine using a novel rabbit model. Rabbits in the experimental group were placed into individual tubes specifically designed to force maintenance of an upright posture and were loaded with a heavy collar to increase the intradiscal pressure of their lumbar spine. Radiograph imaging and magnetic resonance imaging (MRI) was performed every 4 weeks to provide evidence of disc degeneration. At the end of the experiment, the animals were sacrificed and disc specimens were harvested for quantitative polymerase chain reaction and histological analysis. MRI results revealed significant and progressive reductions in the signal intensities of lumbar discs in the experimental group compared with the control group throughout the 14-week study period. The expression level of type I collagen was significantly increased and the expression levels of type II collagen and aggrecan were significantly decreased in the experimental group compared with the control group (P<0.05). Histological examination revealed marked structural changes in the experimental group, including fibrocartilage-like tissue ingrowth and accelerated fibrotic changes of the nucleus pulposus. The results of the present study indicate that noninvasive cumulative axial load is able to induce accelerated degenerative changes in rabbit lumbar discs, which may provide useful information for the establishment of a novel animal model of IDD for the research of IDD in humans.

In vitro Antiproliferative and Apoptosis Inducing Effect of Allium atroviolaceum Bulb Extract on Breast, Cervical, and Liver Cancer Cells

Natural products are considered potent sources for novel drug discovery and development. The multiple therapeutic effects of natural compounds in traditional medicine motivate us to evaluate the cytotoxic activity of bulb of Allium atroviolaceum in MCF7 and MDA-MB-231, HeLa and HepG2 cell lines. The bulb methanol extract of A. atroviolaceum was found to be an active cell proliferation inhibitor at the time and dose dependent manner. Determination of DNA content by flow cytometry demonstrated S and G2/M phase arrest of MCF-7 cell, correlated to Cdk1 downregulation, S phase arrest in MDA-MB-231 which is p53 and Cdk1-dependent, sub-G0 cell cycle arrest in HeLa aligned with Cdk1 downregulation, G0/G1, S, G2/M phase arrest in HepG2 which is p53-dependent. Apoptosis as the mechanism of cell death was confirmed by morphology study, caspases activity assay, as well as apoptosis related gene expression, Bcl-2. Caspase-8, -9, and -3 activity with downregulation of Bcl-2 illustrated occurrence of both intrinsic and extrinsic pathways in MCF7, while caspase-3 and -8 activity revealed extrinsic pathway of apoptosis, although Bcl-2 downregulated. In HeLa cells, the activity of caspase-9 and -3 and downregulation of Bcl-2 shows intrinsic pathway or mitochondrial pathway, whereas HepG2 shows caspase independent apoptosis. Further, the combination of the extract with tamoxifen against MCF7 and MDA-MB-231 and combination with doxorubicin against HeLa and HeG2 demonstrated synergistic effect in most concentrations, suggests that the bulb of A. atroviolaceum may be useful for the treatment of cancer lonely or in combination with other drugs.

Enhancement of Exposure and Reduction of Elimination for Paeoniflorin or Albiflorin via Co-Administration with Total Peony Glucosides and Hypoxic Pharmacokinetics Comparison

There is evidence suggesting that herbal extracts demonstrate greater bioactivities than their isolated constituents at an equivalent dose. This phenomenon could be attributed to the absence of interacting substances present in the extracts. By measuring the pharmacokinetic parameters of paeoniflorin (PF) and albiflorin (AF) after being orally administered to rats in isolated form, in combination with each other and within total peony glucosides (TPG), respectively, the current study aimed to identify positive pharmacokinetic interactions between components of peony radix extracts. Moreover, the pharmacokinetic profiles of PF and AF under normoxia and hypoxia were also investigated and compared. In order to achieve these goals, a highly sensitive and reproducible ultra-peformance liquid chromatography-mass spectrometry (UPLC-MS) method was developed and validated for simultaneously quantitation of PF and AF in rat plasma. This study found that compared with that of single component (PF/AF), the exposure of PF in rat plasma after combination administration or TPG administration was significantly increased, meanwhile the elimination of PF/AF was remarkably reduced. It was also noticed that AUC and Cmax of PF in hypoxia rats were significantly decreased compared with that of normaxia rats, suggesting that there was a decreased exposure of PF in rats under hypoxia. The current study, for the first time, revealed the pharmacokinetic interactions between PF/AF and other constitutes in TGP and the pharmacokinetic profiles of PF and AF under hypoxia. In view of the current findings, it could be supposed that the clinical performance of total peony glucosides would be better than that of single constitute (PF/AF). The outcomes of this animal study are expected to serve as a basis for development of clinical guidelines on total peony glucosides usage.

Volatile Oil of Acori Graminei Rhizoma-Induced Apoptosis and Autophagy are dependent on p53 Status in Human Glioma Cells

Acori Graminei Rhizoma is well known for the beneficial effects on CNS disorders in traditional medicine. Though it is frequently prescribed in formulations for brain tumors, the anti-glioma effect has not been examined. We used volatile oil of Acori Graminei Rhizoma (VOA) and human glioblastoma multiforme (GBM) cells in this study. We found that VOA exhibited greater growth suppression in p53 wild-type cells than p53 mutant cells and very low effect on fibroblasts and human glial HEB cells. Apoptosis was triggered by VOA with a caspase-dependent way in p53 wild-type A172 cells, while a caspase-independent way in p53 mutant U251 cells. Meanwhile, both A172 and U251 cells treated by VOA displayed autophagic features. Furthermore, p53 decrease was observed along with VOA-induced apoptosis and autophagy in A172 cells. VOA-induced autophagy was mediated through a p53/AMPK/mTOR signaling pathway in A172 cells, while an mTOR-independent signaling pathway in U251 cells. Finally, blockage of autophagy potentiated the proapoptotic effect in both A172 and U251 cells, indicating a protective role of autophagy in VOA-induced cell death. Together, VOA exhibited anti-tumor activity in human GBM cells and induced apoptotic cell death and protective autophagy, which is cell type specific and dependent on p53 status.

STUDIES OF MOLECULAR CHANGES IN INTERVERTEBRAL DISC DEGENERATION IN ANIMAL MODEL

Objective:

To evaluate the structural and molecular changes in the extracellular matrix (ECM) during the process of intervertebral disc degeneration, using animal model.

Methods:

Wistar rats underwent intervertebral disc degeneration through 20-gauge needle puncture, and 360° rotation applied for 30 sec, representing the degenerated group, while control group was not submitted to this procedure. Histological parameters and expression of extracellular matrix molecules were evaluated in the 15^th and 28^th days after degenerative induction.

Results:

Fifteen days after the induction of intervertebral disc degeneration, significant changes were observed, such as reduction in the expression metalloprotease-9 (MMP9) and interleukins (IL-6 and IL-10). There was a significant increase in the expression of vascular endothelial growth factor (VEGF) and caspase-3. However, different alterations in the ECM were observed at 28 days, the level of collagen I, metalloprotease-2 (MMP2) and caspase-3 were enhanced. Furthermore, expression of heparanase isoforms (HPSE1 and HPSE2) mRNA were increased in the degenerative intervertebral disc.

Conclusion:

The different profiles of ECM molecules observed during the intervertebral disc degeneration suggest that molecular processes such as ECM remodeling, neovascularization, apoptosis and inflammation occur. Experimental Study.