Surgical Outcomes of Extensive Dome-Like Laminoplasty Using En Bloc Resection of C2 Inner Lamina for Patients With Severe Cord Compression Behind C2 Body.

STUDY DESIGN: A retrospective, single-center study. OBJECTIVE: The aim of this study is to evaluate the efficacy and safety of a newly developed extensive dome-like laminoplasty using en bloc resection of the C2 inner lamina in patients with severe cord compression behind the C2 body. SUMMARY OF BACKGROUND DATA: A surgery for severe cord compression behind C2 body is challenging for spinal surgeons. To date, there has been no established solution for severe cord compression behind the C2 body. MATERIALS AND METHODS: Patients with severe cord compression behind the C2 body who underwent posterior surgery consecutively were enrolled. Extensive dome-like laminoplasty that was newly developed was performed to remove en bloc removal of the C2 inner lamina were performed. Preoperative and postoperative canal diameters behind the C2 and mean removed area of the C2 inner lamina were measured using MRI and CT scan. Clinical and radiographic parameters were assessed preoperative and postoperative periods. In addition, perioperative complications were analyzed. RESULTS: A total of 36 patients underwent extensive dome-like laminoplasty and their diagnoses were ossification of the posterior longitudinal ligament (OPLL, 66.7%) and congenital stenosis with spondylosis (33.3%). The mean canal diameter behind the C2 increased from 9.85 (2.28) mm preoperatively to 19.91 (3.93) mm at the last follow-up ( P <0.001). Clinically, neck and arm visual analog scale, Japanese Orthopaedic Association score, and neck disability index significantly improved at postoperative 1 month ( P <0.05), and the scores were maintained until the last follow-up. No meaningful radiographic changes occurred after the surgeries. During the procedures, there were no particular complications, but one patient showed deteriorated myelopathic symptoms and underwent additional C1-C2 decompressive surgery. CONCLUSIONS: After extensive dome-like laminoplasty, surgical outcomes are satisfactory, and complications are rare. This technique may be a viable option for patients with severe cord compression behind the C2 body. LEVEL OF EVIDENCE: Level IV.

Evaluation of Physical Properties of Coated Polydioxanone Threads.

BACKGROUND: Using a thread for wound closure promotes healing and minimizes contamination by foreign substances. Threads have also been employed in esthetic surgery; however, functional threads that can improve wrinkles and rejuvenate the skin are required. OBJECTIVE: To evaluate the suitability of polydioxanone threads coated with polyethylene glycol, hyaluronic acid, and amino acids for use in the medical field because such formulations are expected to promote regeneration and collagen synthesis. MATERIALS AND METHODS: Physical properties (diameter [ n = 20], tensile strength [ n = 20], strength retention rate [ n = 10], and scanning electron microscopy images) and cytotoxicity (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays) of polydioxanone threads coated with polyethylene glycol, hyaluronic acid, and amino acids were assessed and compared with those of uncoated polydioxanone threads. Analyses were performed using IBM SPSS Statistics (Statistical significance; p values <.05). RESULTS: The size standards for tensile strength (≥63.5 N) and diameter (average 0.570-0.610 mm) were met. There were no differences in the physical properties of the coated and uncoated threads; however, the biocompatibility of coated threads was high owing to low cytotoxicity. CONCLUSION: Threads coated with materials that can promote regeneration are suitable for use in the medical field.

Protective Effects of Withagenin A Diglucoside from Indian Ginseng (Withania somnifera) against Human Dermal Fibroblast Damaged by TNF-α Stimulation.

Human skin is constructed with many proteins such as collagen and elastin. Collagen and elastin play a key role in providing strength and elasticity to the human skin and body. However, damage to collagen causes various symptoms such as wrinkles and freckles, which suggests that they are important to maintain skin condition. Extrinsic or intrinsic skin aging produces an excess of skin destructive factors such as tumor necrosis factor (TNF)-α, which is a major mediator of the aging process. In aged skin, TNF-α provokes the generation of intracellular ROS (reactive oxygen species). It triggers the excessive secretion of MMP-1, which is a collagen-degrading enzyme that causes the collapse of skin collagen. Therefore, we aimed to search for a natural-product-derived candidate that inhibits the skin damage caused by TNF-α in human dermal fibroblasts. In this study, the protective effect of withagenin A diglucoside (WAD) identified from Withania somnifera against TNF-α-stimulated human dermal fibroblasts is investigated. W. somnifera (Solanaceae), well-known as 'ashwagandha', is an Ayurvedic medicinal plant useful for promoting health and longevity. Our experimental results reveal that WAD from W. somnifera suppresses the generation of intercellular ROS. Suppressing intracellular ROS generation inhibits MMP-1 secretion and the collapse of type 1 collagen. The effect of WAD is shown to depend on the inhibition of MAPK phosphorylation, Akt phosphorylation, c-Jun phosphorylation, COX-2 expression, and NF-κB phosphorylation. Further, WAD-depressed expression of the pro-inflammatory cytokines IL-6 and IL-8 triggers various inflammatory reactions in human skin. These findings suggest that WAD has protective effects against skin damage. Accordingly, our study provides experimental evidence that WAD can be a potential agent that can be applied in various industrial fields, such as cosmetics and pharmaceuticals related to skin aging.

Cervical Radiculopathy: Focus on Factors for Better Surgical Outcomes and Operative Techniques.

For patients with cervical radiculopathy, most studies have recommended conservative treatment as the first-line treatment; however, when conventional treatment fails, surgery is considered. A better understanding of the prognosis of cervical radiculopathy is essential to provide accurate information to the patients. If the patients complain of persistent and recurrent arm pain/numbness not respond to conservative treatment, or exhibit neurologic deficits, surgery is performed using anterior or posterior approaches. Anterior cervical discectomy and fusion (ACDF) has historically been widely used and has proven to be safe and effective. To improve surgical outcomes of ACDF surgery, many studies have been conducted on types of spacers, size/height/position of cages, anterior plating, patients' factors, surgical techniques, and so forth. Cervical disc replacement (CDR) is designed to reduce the incidence of adjacent segment disease during long-term follow-up by maintaining cervical spine motion postoperatively. Many studies on excellent indications for the CDR, proper type/size/shape/height of the implants, and surgical techniques were performed. Posterior cervical foraminotomy is a safe and effective surgical option to avoid complications associated with anterior approach and fusion surgery. Most recent literature demonstrated that all three surgical techniques for patients with cervical radiculopathy have clear advantages and disadvantages and reveal satisfactory surgical outcomes under a proper selection of patients and application of appropriate surgical methods. For this, it is important to fully understand the factors for better surgical outcomes and to adequately practice the operative techniques for patients with cervical radiculopathy.

Biological Potential of Polyethylene Glycol (PEG)-Functionalized Graphene Quantum Dots in In Vitro Neural Stem/Progenitor Cells.

Stem cell therapy is one of the novel and prospective fields. The ability of stem cells to differentiate into different lineages makes them attractive candidates for several therapies. It is essential to understand the cell fate, distribution, and function of transplanted cells in the local microenvironment before their applications. Therefore, it is necessary to develop an accurate and reliable labeling method of stem cells for imaging techniques to track their translocation after transplantation. The graphitic quantum dots (GQDs) are selected among various stem cell labeling and tracking strategies which have high photoluminescence ability, photostability, relatively low cytotoxicity, tunable surface functional groups, and delivering capacity. Since GQDs interact easily with the cell and interfere with cell behavior through surface functional groups, an appropriate surface modification needs to be considered to get close to the ideal labeling nanoprobes. In this study, polyethylene glycol (PEG) is used to improve biocompatibility while simultaneously maintaining the photoluminescent potentials of GQDs. The biochemically inert PEG successfully covered the surface of GQDs. The PEG-GQDs composites show adequate bioimaging capabilities when internalized into neural stem/progenitor cells (NSPCs). Furthermore, the bio-inertness of the PEG-GQDs is confirmed. Herein, we introduce the PEG-GQDs as a valuable tool for stem cell labeling and tracking for biomedical therapies in the field of neural regeneration.

Pulveraven A from the fruiting bodies of Pulveroboletus ravenelii induces apoptosis in breast cancer cell via extrinsic apoptotic signaling pathway.

Pulveroboletus ravenelii (Beck. et Curt.) Murr. (Boletaceae), commonly known as Ravenel's bolete, is an edible and medicinal mushroom, and is also used for preparing mushroom-based dyes. As part of a continuing project to discover the bioactive natural products from wild mushrooms, we analyzed the methanol (MeOH) extract of P. ravenelii to identify metabolites with the anticancer activity. Chemical analysis of the MeOH extract combined with liquid chromatography-mass spectrometry (LC-MS) analysis led to the isolation of a phenolic compound, pulveraven A (PA), whose chemical structure was determined using a combination of 1D and 2D NMR and LC-MS analysis. In the present study, we investigated the cytotoxicity and anticancer mechanisms of pulveraven A using human breast cancer (MCF-7) cells, and demonstrated that it reduced cell viability of MCF-7 cells below 50% (71.74 ± 3.61 µM). Annexin V Alexa Fluor 488 binding assay and western blot results revealed that pulveraven A induced apoptotic cell death via the extrinsic apoptosis pathway, as indicated by the activation of initiator caspase-8 and executioner caspase-7. Furthermore, it was accompanied by an increase in the Bax/Bcl-2 ratio. These results suggest that pulveraven A induces apoptosis in breast cancer cells via the extrinsic apoptotic signaling pathway.

Phloridzin Acts as an Inhibitor of Protein-Tyrosine Phosphatase MEG2 Relevant to Insulin Resistance.

Inhibition of the megakaryocyte protein tyrosine phosphatase 2 (PTP-MEG2, also named PTPN9) activity has been shown to be a potential therapeutic strategy for the treatment of type 2 diabetes. Previously, we reported that PTP-MEG2 knockdown enhances adenosine monophosphate activated protein kinase (AMPK) phosphorylation, suggesting that PTP-MEG2 may be a potential antidiabetic target. In this study, we found that phloridzin, isolated from Ulmus davidiana var. japonica, inhibits the catalytic activity of PTP-MEG2 (half-inhibitory concentration, IC50 = 32 ± 1.06 µM) in vitro, indicating that it could be a potential antidiabetic drug candidate. Importantly, phloridzin stimulated glucose uptake by differentiated 3T3-L1 adipocytes and C2C12 muscle cells compared to that by the control cells. Moreover, phloridzin led to the enhanced phosphorylation of AMPK and Akt relevant to increased insulin sensitivity. Importantly, phloridzin attenuated palmitate-induced insulin resistance in C2C12 muscle cells. We also found that phloridzin did not accelerate adipocyte differentiation, suggesting that phloridzin improves insulin sensitivity without significant lipid accumulation. Taken together, our results demonstrate that phloridzin, an inhibitor of PTP-MEG2, stimulates glucose uptake through the activation of both AMPK and Akt signaling pathways. These results strongly suggest that phloridzin could be used as a potential therapeutic candidate for the treatment of type 2 diabetes.

3D culture technologies of cancer stem cells: promising ex vivo tumor models.

Cancer stem cells have been shown to be important in tumorigenesis processes, such as tumor growth, metastasis, and recurrence. As such, many three-dimensional models have been developed to establish an ex vivo microenvironment that cancer stem cells experience under in vivo conditions. Cancer stem cells propagating in three-dimensional culture systems show physiologically related signaling pathway profiles, gene expression, cell-matrix and cell-cell interactions, and drug resistance that reflect at least some of the tumor properties seen in vivo. Herein, we discussed the presently available Cancer stem cell three-dimensional culture models that use biomaterials and engineering tools and the biological implications of these models compared to the conventional ones.

Bioactivity-guided isolation of ginsenosides from Korean Red Ginseng with cytotoxic activity against human lung adenocarcinoma cells.

BACKGROUND: Lung cancer is the leading cause of cancer-related death worldwide. In this study, we used a bioactivity-guided isolation technique to identify constituents of Korean Red Ginseng (KRG) with antiproliferative activity against human lung adenocarcinoma cells. METHODS: Bioactivity-guided fractionation and preparative/semipreparative HPLC purification were used with LC/MS analysis to separate the bioactive constituents. Cell viability and apoptosis in human lung cancer cell lines (A549, H1264, H1299, and Calu-6) after treatment with KRG extract fractions and constituents thereof were assessed using the water-soluble tetrazolium salt (WST-1) assay and terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, respectively. Caspase activation was assessed by detecting its surrogate marker, cleaved poly adenosine diphosphate (ADP-ribose) polymerase, using an immunoblot assay. The expression and subcellular localization of apoptosis-inducing factor were assessed using immunoblotting and immunofluorescence, respectively. RESULTS AND CONCLUSION: Bioactivity-guided fractionation of the KRG extract revealed that its ethyl acetate-soluble fraction exerts significant cytotoxic activity against all human lung cancer cell lines tested by inducing apoptosis. Chemical investigation of the ethyl acetatesoluble fraction led to the isolation of six ginsenosides, including ginsenoside Rb1 (1), ginsenoside Rb2 (2), ginsenoside Rc (3), ginsenoside Rd (4), ginsenoside Rg1 (5), and ginsenoside Rg3 (6). Among the isolated ginsenosides, ginsenoside Rg3 exhibited the most cytotoxic activity against all human lung cancer cell lines examined, with IC50 values ranging from 161.1 µM to 264.6 µM. The cytotoxicity of ginsenoside Rg3 was found to be mediated by induction of apoptosis in a caspase-independent manner. These findings provide experimental evidence for a novel biological activity of ginsenoside Rg3 against human lung cancer cells.

7α,15-Dihydroxydehydroabietic acid from Pinus koraiensis inhibits the promotion of angiogenesis through downregulation of VEGF, p-Akt and p-ERK in HUVECs.

Pinus koraiensis pinecones are considered an undesired waste by-product of the processing of seeds. However, recent studies of the potential anti-tumor effects of the pinecones have led to increasing interest in their chemical constituents. The present study examined the potential antiangiogenic effects of the constituents of pinecones and further characterized their underlying mechanisms of action. Chemical investigation of a water extract of P. koraiensis pinecones led to the isolation and identification of the eight main components including five diterpenoids (1-5), two monoterpenes (6,7) and a phenolic acid (8). The structure of the compounds was determined by spectroscopic analysis of NMR spectra and LC/MS analysis. Of the isolated compounds, 7α,15-dihydroxydehydroabietic acid (5) significantly inhibited the promotion of angiogenesis in human umbilical vein endothelial cells (HUVECs). Compound 5 inhibited angiogenesis through downregulation of the VEGF, p-Akt and p-ERK signaling pathways. These results provide experimental evidence of a novel biological activity of 7α,15-dihydroxydehydroabietic acid (5) as a potential antiangiogenic substance. This study also suggests that compound 5 could potentially be a useful adjuvant therapeutic substance for cancer prevention and treatment.

Identification of bioactive heterocyclic compounds from mulberry and their protective effect against streptozotocin-induced apoptosis in INS-1 cells.

A phytochemical investigation of the MeOH extracts from mulberries (the fruit of Morus alba L.) led to the identification of six heterocyclic compounds (1­6). These compounds were screened to detect whether they protected pancreatic INS­1 cells from streptozotocin (STZ)­induced cytotoxicity. Compound 3 was the most effective at preventing STZ­induced cytotoxicity and the production of reactive oxygen species (ROS) in INS­1 cells. In addition, compound 3 effectively prevented apoptosis induced by STZ in INS­1 cells. Compound 3 also prevented STZ­mediated cleavage of caspase­8, caspase­3 and poly (ADP­ribose) polymerase and increased the expression of B­cell lymphoma­2 (Bcl­2), an anti­apoptotic Bcl­2 family protein. In conclusion, the results of the present study indicate that compound 3 extracted from the fruit of M. alba was highly effective in preventing type 1 diabetes mellitus and may be a novel treatment option.

Curcuzedoalide contributes to the cytotoxicity of Curcuma zedoaria rhizomes against human gastric cancer AGS cells through induction of apoptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Curcuma zedoaria Roscoe (Zingiberaceae), also known as white turmeric or zedoaria, has been used in Ayurveda and traditional Chinese medicine to treat various cancers, and it possesses several sesquiterpenoid compounds. OBJECTIVE: This study aimed to evaluate the therapeutic effects of a methanolic (MeOH) extract of C. zedoaria rhizomes, as well as its active constituents, against gastric cancer, which is a frequently diagnosed cancer in South Korea. MATERIALS AND METHODS: Repeated column chromatography, together with semi-preparative HPLC purification, was used to separate the bioactive constituents from the C. zedoaria MeOH extract. The cytotoxic effects of the C. zedoaria MeOH extract and its active compounds were measured in human gastric cancer AGS cells. Expression of proteins related to apoptosis was evaluated using Western blotting analysis. RESULTS: The MeOH extract of C. zedoaria rhizomes exerted a cytotoxic effect on AGS cells (IC50: 96.60 ± 4.87µg/mL). Based on the bioactivity-guided fractionation for antiproliferative activity, a chemical investigation of the MeOH extract led to the isolation of five sesquiterpenes including isoprocurcumenol (1), germacrone (2), curzerenone (3), curcumenol (4), and curcuzedoalide (5). Among these, curcuzedoalide demonstrated the strongest effect in suppressing gastric cancer cell proliferation in a dose-dependent manner with an IC50 value of 125.11±2.77µM. Western blotting analysis showed that curcuzedoalide inhibited AGS human gastric cancer cell viability by activating caspase-8, caspase-9, caspase-3, and PARP, which contributed to apoptotic cell death in AGS human gastric cancer cells. CONCLUSION: These data indicate that curcuzedoalide contributed to the cytotoxicity of C. zedoaria by activating the cleavage of caspases and PARP, which are representative markers for apoptosis. Therefore, curcuzedoalide is a positive candidate for the development of novel chemotherapeutics.

Chemical characterization of cytotoxic indole acetic acid derivative from mulberry fruit (Morus alba L.) against human cervical cancer.

The fruit of the white mulberry tree (Morus alba L.) is a multiple fruit with a sweet flavor commonly consumed around the world. Chemical investigation of the fruits led to the isolation of two indole acetic acid derivatives (1 -2) including a new compound, which turned out to be an isolation artifact, 3S-(ß-D-glucopyranosyloxy)-2,3-dihydro-2-oxo-1H-indole-3-acetic acid butyl ester (1), along with five known compounds (3 -7). Compounds 2 and 7 were newly identified from mulberry fruit. The new isolation artifact (1) exhibited cytotoxic effect on human cervical cancer Hela cells in a dose-dependent manner. Compound 1 activated caspase-8, caspase-9, and caspase-3, followed by cleavage of PARP, a substrate of caspase-3, in a dose-dependent manner. Simultaneous alterations in protein expression of mitochondrial factors Bax, BID and Bcl-2 were also observed. A comparison between compounds 1 and 2 led to a structure-activity relationship analysis of the cytotoxic effect. These results suggest that compound 1 could be beneficial in human cervical cancer treatment, and provide a theoretical basis for further application of compound 1.

Anti-Inflammatory Phenolic Metabolites from the Edible Fungus Phellinus baumii in LPS-Stimulated RAW264.7 Cells.

The edible fungus Phellinus baumii Pilat (Hymenochaetaceae) has been used in Korean traditional medicines for strengthening health and prolonging life. An extract of the fruiting bodies of P. baumii was subjected to bioassay-guided fractionation based on its anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The resulting fractions were chemically investigated, leading to isolation of three phenolic compounds (1-3), a sesquiterpene (4), two steroids (5-6), a fatty acid (7), and a cerebroside (8). Spectroscopic analyses including 1D and 2D NMR spectroscopy and LC/MS were used to determine their chemical structures. Compounds 2, 4, 5, 7 and 8 were identified in P. baumii for the first time. Since all compounds were isolated from active fractions with anti-inflammatory activity, their ability to inhibit LPS-stimulated nitric oxide (NO) production in RAW264.7 cells were evaluated in vitro. Compounds 1, 2, 3, 5 and 7 inhibited LPS-stimulated NO production, and compounds 1-3 had IC50 values <10 µM. Treatment of LPS-stimulated RAW264.7 cells with compounds 1-3 inhibited phosphorylation of IKKα and IκBα. In addition, treatment of compounds 1-3 reduced LPS-induced increases of nuclear factor-kappa B (NF-κB) p65, iNOS and COX-2 protein expressions. Collectively, compounds 1-3 inhibited NF-κB-dependent inflammation in RAW264.7 cells. Thus, P. baumii is a potential source of natural anti-inflammatory agents, and active compounds 1-3 could be promising lead compounds for the development of novel anti-inflammatory agents.

Chemical constituents from the rare mushroom Calvatia nipponica inhibit the promotion of angiogenesis in HUVECs.

Calvatia species, also known as puffball mushrooms, are common sources of food worldwide. Calvatia nipponica (Agaricaceae) is one of the most rare species in the Calvatia genus. It was first validated in 2008. Due to its scarcity, C. nipponica has never been chemically investigated. Its recent discovery in Korea allowed to conduct this study, and using bioactivity-guided fractionation for antiangiogenic activity, chemical investigation of the MeOH extract of the fruiting bodies of C. nipponica led to the isolation of five alkaloids (1-5) and two phenolic compounds (6-7). This is the first study to report the chemical investigation of C. nipponica, and compound 1 was previously reported as chemically synthesized only until our report of its isolation and identification from natural sources. The structure of 1 was determined by spectroscopic analysis by 1D and 2D NMR spectra and HR-MS. All compounds (1-7) were tested for inhibition of angiogenesis using human umbilical vein endothelial cells (HUVECs). Compounds 2, 4 and 5 significantly inhibited the promotion of angiogenesis in HUVECs. Compound 5 showed the most potent inhibition via downregulation of VEGF, p38 and ERK signaling pathways. These results suggested that the rare mushroom C. nipponica might be beneficial in antiangiogenesis therapy for cancer treatment.

Cytotoxic effect of sanguiin H-6 on MCF-7 and MDA-MB-231 human breast carcinoma cells.

Sanguiin H-6 is a dimer of casuarictin linked by a bond between the gallic acid residue and one of the hexahydroxydiphenic acid units. It is an effective compound extracted from Rubus coreanus. It has an anticancer effect against several human cancer cells; however, its effect on breast cancer cells has not been clearly demonstrated. Thus, we aimed to investigate the anticancer effect and mechanism of action of sanguiin H-6 against two human breast carcinoma cell lines (MCF-7 and MDA-MB-231). We found that sanguiin H-6 significantly reduced cell viability in a concentration-dependent manner. It also increased the rates at which MCF-7 and MDA-MB-231 cells underwent apoptosis. Furthermore, sanguiin H-6 induced the cleavage of caspase-8, caspase-3, and poly(ADP-ribose) polymerase, which resulted in apoptosis. However, cleavage of caspase-9 was only detectable in MCF-7 cells. In addition, sanguiin H-6 increased the ratio of Bax to Bcl-2 in both MCF-7 and MDA-MB-231 cells. These findings suggest that sanguiin H-6 is a potent therapeutic agent against breast cancer cells. In addition, it exerts its anticancer effect in an estrogen-receptor-independent manner.

Evaluation of guggulsterone derivatives as novel kidney cell protective agents against cisplatin-induced nephrotoxicity.

Guggulsterone derivatives were prepared using [3+2] click chemistry with aryl and alkyl acetylene. The series of derivatives were evaluated for their cellular protective effects on cisplatin-treated cultured LLC-PK1 kidney epithelial cells. Among the guggulsterone-triazole derivatives, compound 6g, which contains a hydroxyl methyl group, was the most active of all the derivatives. In an additional study, we determined that inhibition of the mitogen-activated protein kinase/caspase-3 signaling cascade by 6g mediates its protective effects against cytotoxicity in cultured LLC-PK1 cells.

Protective effect of lanostane triterpenoids from the sclerotia of Poria cocos Wolf against cisplatin-induced apoptosis in LLC-PK1 cells.

Cisplatin-induced nephrotoxicity is a serious adverse effect that limits the use of cisplatin in cancer patients. In the present study, we investigated the protective effect of lanostane triterpenoids (1-10) isolated from the ethanolic extract of Poria cocos Wolf against cisplatin-induced cell death in LLC-PK1 kidney tubular epithelial cells. Treatment of cisplatin induced significant cell death, which was suppressed by treatment with dehydroeburicoic acid monoacetate (1) and 3ß-acetoxylanosta-7,9(11),24-trien-21-oic acid (9). Compound 1 exhibited the highest efficacy among the tested compounds and was thus subjected to further mechanistic studies. The increase in the percentage of apoptotic cells induced by cisplatin reduced by 4.3% after co-treatment of cells with compound 1 (50 and 100µM). Furthermore, phosphorylation of the mitogen-activated protein kinases JNK, ERK, and p38, and caspase-3, which characterize oxidative stress-mediated apoptosis, increased significantly after treatment with cisplatin, and decreased after treatment with compound 1. These results indicate that the renoprotective effects of compound 1 may be mediated by its anti-apoptotic activity.

Inhibitory effect of flavonoids against NS2B-NS3 protease of ZIKA virus and their structure activity relationship.

OBJECTIVES: To determine the inhibitory activities of flavonoids against NS2B-NS3 protease of ZIKA virus (ZIKV NS2B-NS3pro) expressed in Escherichia coli BL21 (DE3) and their structure activity relationship. RESULTS: ZIKV NS2B-NS3pro was expressed in E. coli BL21(DE3) as a 35 kDa protein. It had a K m of 26 µM with the fluorogenic peptide Dabcyl-KTSAVLQSGFRKME-Edan. The purified ZIKV NS2B-NS3pro was used for inhibition and kinetic assays to determine the activities of 22 polyphenol compounds. These polyphenol compounds at 100 µM inhibited the activity of ZIKV NS2B-NS3pro by 6.2-88%. Seven polyphenol compounds had IC50 ranging from 22 ± 0.2 to 112 ± 5.5 µM. Myricetin showed a mixed type inhibitory pattern against ZIKV NS2B-NS3pro protease. Its IC50 value was 22 ± 0.2 µM with a K i value of 8.9 ± 1.9 µM. CONCLUSION: The chemical structure of a polyphenol compound and its inhibitory activity against ZIKV NS2B-NS3pro can be explored to develop highly selective inhibitors against ZIKV NS2B-NS3pro.

Quercetin suppresses invasion and migration of H-Ras-transformed MCF10A human epithelial cells by inhibiting phosphatidylinositol 3-kinase.

Quercetin is a major flavonoid compound found in red wine at a much higher concentration than the phytoalexin resveratrol. In this study, we examined potential anti-metastatic effects and found that compared to resveratrol, quercetin more potently inhibits H-Ras-induced invasion and migration in MCF10A human epithelial cells, an effect likely mediated by the mitigation of matrix metalloproteinase (MMP)-2 activation. We then measured Akt phosphorylation to investigate whether the decreased MMP-2 activation was attributable to the inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signalling. Quercetin, but not resveratrol at equivalent concentrations, suppressed the phosphorylation of Akt and was a more potent inhibitor of PI3K activity than resveratrol. An ex vivo binding assay further revealed that quercetin directly binds to PI3K. Collectively, these results suggest that PI3K is a molecular target of quercetin for the inhibition of H-Ras-induced invasion and migration of MCF10A cells.