Effects of Ozone on Injury after Gamma Knife Radiosurgery.

BACKGROUND: At present, gamma knife radiosurgery plays an important role in neurosurgical procedures. Gamma knife radiosurgery has been used to treat many types of brain tumors and as a functional intervention. However, gamma knife treatment has a devastating effect on the normal brain parenchyma surrounding the target point. It causes increased vascular permeability, vasodilation, and swelling in endothelial cells. Ozone has antioxidant, antiapoptotic, and anti-inflammatory effects in the body. Thus, we evaluated the radioprotective effects of ozone in rats undergoing gamma knife radiation. METHODS: In the present study, 24 Sprague-Dawley male rats weighing 250-300 g in 3 groups of 8 rats each were used. The rats were selected randomly. The control group did not receive any gamma knife radiation. The other 2 groups received 50 Gy of radiation, with 1 group given ozone treatment and the other group not given ozone treatment after gamma knife radiosurgery. At 12 weeks after gamma knife radiation, the rats were sacrificed with high-dose anesthetic agents and the tissues prepared for evaluation. The slides were evaluated for necrosis, vacuolization, glial proliferation, and vascular proliferation using hematoxylin-eosin staining. Vascular endothelial growth factor (VEGF) and extracellular matrix metalloproteinase inducer (also known as CD147) were evaluated using immunohistochemical staining. RESULTS: VEGF expression in glial tissue was significantly less in the group receiving ozone (χ2 = 15.00; df = 4; P = 0.005) compared with the group that had not received ozone and was similar to the expression in the control group. CONCLUSIONS: The lower expression of VEGF in the group receiving ozone might cause less edema in the surrounding tissue owing to less degradation of vascular permeability in the rat brain tissue.

Ivabradine-Stimulated Microvesicle Release Induces Cardiac Protection against Acute Myocardial Infarction.

Ivabradine can reduce heart rate through inhibition of the current I(f) by still unexplored mechanisms. In a porcine model of ischemia reperfusion (IR), we found that treatment with 0.3 mg/kg Ivabradine increased plasma release of microvesicles (MVs) over Placebo, as detected by flow cytometry of plasma isolated from pigs 7 days after IR, in which a tenfold increase of Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) containing (both high and low-glycosylated) MVs, was detected in response to Ivabradine. The source of MVs was investigated, finding a 37% decrease of CD31+ endothelial cell derived MVs, while CD41+ platelet MVs remained unchanged. By contrast, Ivabradine induced the release of HCN4+ (mostly cardiac) MVs. While no differences respect to EMMPRIN as a cargo component were found in endothelial and platelet derived MVs, Ivabradine induced a significant release of EMMPRIN+/HCN4+ MVs by day 7 after IR. To test the role of EMMPRIN+ cardiac MVs (EMCMV), H9c2 cell monolayers were incubated for 24 h with 107 EMCMVs, reducing apoptosis, and increasing 2 times cell proliferation and 1.5 times cell migration. The in vivo contribution of Ivabradine-induced plasma MVs was also tested, in which 108 MVs isolated from the plasma of pigs treated with Ivabradine or Placebo 7 days after IR, were injected in pigs under IR, finding a significant cardiac protection by increasing left ventricle ejection fraction and a significant reduction of the necrotic area. In conclusion ivabradine induces cardiac protection by increasing at least the release of EMMPRIN containing cardiac microvesicles.

Resveratrol Abrogates Hypoxia-Induced Up-Regulation of Exosomal Amyloid-ß Partially by Inhibiting CD147.

Hypoxia promotes both total extracellular and exosomal amyloid-ß (Aß) production and aggravates Alzheimer's disease (AD). Resveratrol (RSV) has been proved to be neuroprotective in AD models, and down-regulated the expression of CD147, an additional subunit of γ-secretase. In this study, we aimed to explore the role and mechanisms of RSV in hypoxia-induced upregulation of Aß, especially exosomal Aß. SH-SY5Y cells and HEK293 cells overexpressing amyloid precursor protein (APP) as well as C57BL/6 mice were treated with RSV and exposed to hypoxic conditions. The expression of SIRT1 or CD147 was modulated by transfection of specific siRNAs or plasmid. Aß1-40 and Aß1-42 levels were determined by ELISA. Hypoxia increased the levels of both Aß1-40 and Aß1-42 in the hippocampal lysates and serum-derived exosomes of mice. Hypoxia also increased both Aß1-40 and Aß1-42 levels in the total culture medium (CM), cell-derived exosomal lysates, and exosome-free CM of both cell lines. Treatment with RSV abrogated these changes in Aß expression, inhibited the hypoxia-induced down-regulation of SIRT1 and up-regulation of CD147. Knockdown of SIRT1 promote total Aß level but has no effect on exosomal Aßs expression. Knockdown of CD147 inhibits both total and exosomal Aßs expression. Furthermore, overexpressing CD147 in cells exposed to hypoxia facilitated the production of Aß1-40 and Aß1-42, while application of RSV reduced the CD147 expression as well as Aß levels in both exosomes and exosome-free CM. These results suggested that RSV abrogated hypoxia-induced up-regulation of total and exosomal Aß partially by inhibiting CD147.

Propionate and butyrate induce gene expression of monocarboxylate transporter 4 and cluster of differentiation 147 in cultured rumen epithelial cells derived from preweaning dairy calves.

Short-chain fatty acids (SCFAs) are the main source of energy for postweaning ruminants. The monocarboxylic acid transporters, MCT1 and MCT4, are thought to contribute to the absorption of SCFAs from the surface of the rumen following weaning. The present study measured changes in MCT1 and MCT4 expression in ruminal epithelial cells isolated from male preweaning (22 to 34 d old, n = 6) and postweaning (55 to 58 d old, n = 8) calves after euthanasia and sought to examine whether SCFAs stimulate the expression of these transporters. In the current study, cluster of differentiation 147 (CD147) gene expression in the rumen was also investigated since CD147 has been considered to act as ancillary protein for MCT1 and MCT4 to express their correct function. The gene expression levels of MCT1, MCT4, and CD147 in the rumen were found to be significantly higher in postweaning calves than in preweaning calves. Strong MCT1 immunoreactivity was detected in both the stratum basale (SB) and the stratum spinosum (SS) in postweaning ruminal epithelium. Expression of MCT1 in preweaning calves was localized to a specific region of the SB and of the SS. MCT4-immunopositive cells were detected in the stratum corneum (SC) of the ruminal epithelium in postweaning calves. However, only a low level of signal was detected in the SC of preweaning animals. Furthermore, in vitro experiments, ruminal epithelial cells were incubated for 24 h with acetate (0.04, 0.4, and 4 mM), propionate (0.2, 2, and 20 mM), butyrate (0.1, 1, and 10 mM), or ß-hydroxybutyrate (BHBA; 0.1, 1, and 10 mM), respectively. Both propionate and butyrate induced an increase in the gene expression levels of MCT4 and CD147, but did not affect MCT1 gene expression. There are no significant effects of acetate and BHBA treatment on these gene expressions. Taken together, these results suggest that an increase in MCT4 and CD147 gene expression in the ruminal epithelium of postweaning calves is likely to be due to the effects of propionate and butyrate derived from a solid-based diet, which may contribute to ruminal development following weaning.

N-glycosylation by N-acetylglucosaminyltransferase V enhances the interaction of CD147/basigin with integrin ß1 and promotes HCC metastasis.

While the importance of protein N-glycosylation in cancer cell migration is well appreciated, the precise mechanisms by which N-acetylglucosaminyltransferase V (GnT-V) regulates cancer processes remain largely unknown. In the current study, we report that GnT-V-mediated N-glycosylation of CD147/basigin, a tumor-associated glycoprotein that carries ß1,6-N-acetylglucosamine (ß1,6-GlcNAc) glycans, is upregulated during TGF-ß1-induced epithelial-to-mesenchymal transition (EMT), which correlates with tumor metastasis in patients with hepatocellular carcinoma (HCC). Interruption of ß1,6-GlcNAc glycan modification of CD147/basigin decreased matrix metalloproteinase (MMP) expression in HCC cell lines and affected the interaction of CD147/basigin with integrin ß1. These results reveal that ß1,6-branched glycans modulate the biological function of CD147/basigin in HCC metastasis. Moreover, we showed that the PI3K/Akt pathway regulates GnT-V expression and that inhibition of GnT-V-mediated N-glycosylation suppressed PI3K signaling. In summary, ß1,6-branched N-glycosylation affects the biological function of CD147/basigin and these findings provide a novel approach for the development of therapeutic strategies targeting metastasis. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Immunomodulatory drugs disrupt the cereblon-CD147-MCT1 axis to exert antitumor activity and teratogenicity.

Immunomodulatory drugs (IMiDs), such as thalidomide and its derivatives lenalidomide and pomalidomide, are key treatment modalities for hematologic malignancies, particularly multiple myeloma (MM) and del(5q) myelodysplastic syndrome (MDS). Cereblon (CRBN), a substrate receptor of the CRL4 ubiquitin ligase complex, is the primary target by which IMiDs mediate anticancer and teratogenic effects. Here we identify a ubiquitin-independent physiological chaperone-like function of CRBN that promotes maturation of the basigin (BSG; also known as CD147) and solute carrier family 16 member 1 (SLC16A1; also known as MCT1) proteins. This process allows for the formation and activation of the CD147-MCT1 transmembrane complex, which promotes various biological functions, including angiogenesis, proliferation, invasion and lactate export. We found that IMiDs outcompete CRBN for binding to CD147 and MCT1, leading to destabilization of the CD147-MCT1 complex. Accordingly, IMiD-sensitive MM cells lose CD147 and MCT1 expression after being exposed to IMiDs, whereas IMiD-resistant cells retain their expression. Furthermore, del(5q) MDS cells have elevated CD147 expression, which is attenuated after IMiD treatment. Finally, we show that BSG (CD147) knockdown phenocopies the teratogenic effects of thalidomide exposure in zebrafish. These findings provide a common mechanistic framework to explain both the teratogenic and pleiotropic antitumor effects of IMiDs.

A novel small-molecule compound targeting CD147 inhibits the motility and invasion of hepatocellular carcinoma cells.

CD147, a type I transmembrane glycoprotein, is highly expressed in various cancer types and plays important roles in tumor progression, especially by promoting the motility and invasion of hepatocellular carcinoma (HCC) cells. These crucial roles make CD147 an attractive target for therapeutic intervention in HCC, but no small-molecule inhibitors of CD147 have been developed to date. To identify a candidate inhibitor, we used a pharmacophore model derived from the structure of CD147 to virtually screen over 300,000 compounds. The 100 highest-ranked compounds were subjected to biological assays, and the most potent one, dubbed AC-73 (ID number: AN-465/42834501), was studied further. We confirmed that AC-73 targeted CD147 and further demonstrated it can specifically disrupt CD147 dimerization. Moreover, molecular docking and mutagenesis experiments showed that the possible binding sites of AC-73 on CD147 included Glu64 and Glu73 in the N-terminal IgC2 domain, which two residues are located in the dimer interface of CD147. Functional assays revealed that AC-73 inhibited the motility and invasion of typical HCC cells, but not HCC cells that lacked the CD147 gene, demonstrating on-target action. Further, AC-73 reduced HCC metastasis by suppressing matrix metalloproteinase (MMP)-2 via down-regulation of the CD147/ERK1/2/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Finally, AC-73 attenuated progression in an orthotopic nude mouse model of liver metastasis, suggesting that AC-73 or its derivatives have potential for use in HCC intervention. We conclude that the novel small-molecule inhibitor AC-73 inhibits HCC mobility and invasion, probably by disrupting CD147 dimerization and thereby mainly suppressing the CD147/ERK1/2/STAT3/MMP-2 pathways, which are crucial for cancer progression.

EMMPRIN regulates ß1 integrin-mediated adhesion through Kindlin-3 in human melanoma cells.

EMMPRIN is known to promote tumor invasion through extracellular matrix (ECM) degradation. Here we report that EMMPRIN can regulate melanoma cell adhesion to the ECM through an interaction with ß1 integrin involving kindlin-3. In this study, EMMPRIN knockdown in the human melanoma cell line M10 using siRNA decreased cell invasion and significantly increased cell adhesion and spreading. A morphological change from a round to a spread shape was observed associated with enhanced phalloidin-labelled actin staining. In situ proximity ligation assay and co-immunoprecipitation revealed that EMMPRIN silencing increased the interaction of ß1 integrin with kindlin-3, a focal adhesion protein. This was associated with an increase in ß1 integrin activation and a decrease in the phosphorylation of the downstream integrin kinase FAK. Moreover, the expression at both the transcript and protein level of kindlin-3 and of ß1 integrin was inversely regulated by EMMPRIN. EMMPRIN did not regulate either talin expression or its interaction with ß1 integrin. These results are consistent with our in vivo demonstration that EMMPRIN inhibition increased ß1 integrin activation and its interaction with kindlin-3. To conclude, these findings reveal a new role of EMMPRIN in tumor cell migration through ß1 integrin/kindlin-3-mediated adhesion pathway.

EMMPRIN, an upstream regulator of MMPs, in CNS biology.

Matrix metalloproteinases (MMPs) are engaged in pathologies associated with infections, tumors, autoimmune disorders and neurological dysfunctions. With the identification of an upstream regulator of MMPs, EMMPRIN (Extracellular matrix metalloproteinase inducer, CD147), it is relevant to address if EMMPRIN plays a role in the pathology of central nervous system (CNS) diseases. This would enable the possibility of a more upstream and effective therapeutic target. Indeed, conditions including gliomas, Alzheimer's disease (AD), multiple sclerosis (MS), and other insults such as hypoxia/ischemia show elevated levels of EMMPRIN which correlate with MMP production. In contrast, given EMMPRIN's role in CNS homeostasis with respect to regulation of monocarboxylate transporters (MCTs) and interactions with adhesion molecules including integrins, we need to consider that EMMPRIN may also serve important regulatory or protective functions. This review summarizes the current understanding of EMMPRIN's involvement in CNS homeostasis, its possible roles in escalating or reducing neural injury, and the mechanisms of EMMPRIN including and apart from MMP induction.

Gelatinases and extracellular matrix metalloproteinase inducer are associated with cyclosporin-A-induced attenuation of periodontal degradation in rats.

BACKGROUND: The present study aims to examine the inhibitory effect of cyclosporin-A (CsA) on periodontal breakdown and to further explore the correlations of CsA-induced attenuation of periodontal bone loss with the expressions of gelatinases (i.e., matrix metalloproteinase [MMP]-2 and MMP-9) and extracellular matrix metalloproteinase inducer (EMMPRIN). METHODS: Forty Sprague-Dawley rats were randomly divided into four groups: 1) control; 2) CsA; 3) ligature (Lig); and 4) ligature plus CsA (Lig + CsA). The CsA group received 10 mg ⋅ Kg(-1) ⋅ d(-1) CsA for 8 days. The Lig group received silk ligature on selected molars. The Lig + CsA group received silk ligature and CsA treatment. The inhibitory effects of CsA on the ligature-induced periodontal breakdown was examined with microcomputed tomography (micro-CT) and histometric analyses to analyze the amount of attachment loss, crestal bone loss, connective tissue attachment, and the surface area with inflammatory cell infiltration. The effects of CsA on ligature-induced expressions of gelatinases and EMMPRIN in gingival tissues were examined with Western blotting and zymography, respectively. RESULTS: By micro-CT and histology, the Lig + CsA group had significantly more periodontal breakdown than the control and CsA groups but less periodontal breakdown than the Lig group. Consistent results were found for the expressions of gelatinases and EMMPRIN among the groups demonstrating that the Lig + CsA group had significantly less gingival protein expression of gelatinases and EMMPRIN than the Lig group. CONCLUSIONS: CsA inhibited the expressions of gelatinase MMPs and EMMPRIN and partially prevented the periodontal breakdown in ligature-induced experimental periodontitis. The CsA-induced attenuation of periodontal bone loss was strongly correlated positively with the expressions of MMP-2, MMP-9, and EMMPRIN in gingiva.

Curcumin inhibits EMMPRIN and MMP-9 expression through AMPK-MAPK and PKC signaling in PMA induced macrophages.

In coronary arteries, plaque disruption, the major acute clinical manifestations of atherosclerosis, leads to a subsequent cardiac event, such as acute myocardial infarction (AMI) and unstable angina pectoris (UA). Numerous reports have shown that high expression of MMP-9 (matrix metalloproteinase-9), MMP-13 (matrix metalloproteinase-13) and EMMPRIN (extracellular matrix metalloproteinase induce) in monocyte/macrophage results in the plaque progression and destabilization. Curcumin exerts well-known anti-inflammatory and antioxidant effects and probably has a protective role in the atherosclerosis. The purpose of our study was to investigate the molecular mechanisms by which curcumin affects MMP-9, MMP13 and EMMPRIN in PMA (phorbol 12-myristate 13-acetate) induced macrophages. Human monocytic cells (THP-1 cells) were pretreated with curcumin or compound C for 1 h, and then induced by PMA for 48 h. Total RNA and proteins were collected for real-time PCR and Western blot analysis, respectively. In the present study, the exposure to curcumin resulted in attenuated JNK, p38, and ERK activation and decreased expression of MMP-9, MMP-13 and EMMPRIN in PMA induced macrophages. Moreover, we demonstrated that AMPK (AMP-activated protein kinase) and PKC (Protein Kinase C) was activated by PMA during monocyte/macrophage differentiation. Furthermore, curcumin reversed PMA stimulated PKC activation and suppressed the chronic activation of AMPK, which in turn reduced the expression of MMP-9, MMP-13 and EMMPRIN. Therefore, it is suggested that curcumin by inhibiting AMPK-MAPK (mitogen activated protein kinase) and PKC pathway may led to down-regulated EMMPRIN, MMP-9 and MMP-13 expression in PMA-induced THP-1 cells.

A novel extracellular drug conjugate significantly inhibits head and neck squamous cell carcinoma.

OBJECTIVES: Despite advances in treatment modalities, head and neck squamous cell carcinoma (HNSCC) remains a challenge to treat with poor survival and high morbidity, necessitating a therapy with greater efficacy. EDC22 is an extracellular drug conjugate of the monoclonal antibody targeting CD147 (glycoprotein highly expressed on HNSCC cells) linked with a small drug molecule inhibitor of Na, K-ATPase. In this study, EDC22's potential as a treatment modality for HNSCC was performed. MATERIALS AND METHODS: HNSCC cell lines (FADU, OSC-19, Cal27, SCC-1) were cultured in vitro and proliferation and cell viability were assessed following treatment with a range of concentrations of EDC22 (0.25-5.00µg/mL). Mice bearing HNSCC xenografts (OSC-19, SCC-1) were treated with either EDC22 (3-10mg/kg), anti-CD147 monoclonal antibody, cisplatin (1mg/kg) or radiation therapy (2Gy/week) monotherapy or in combination. RESULTS: In vitro, treatment with minimal concentration of EDC22 (0.25µg/mL) significantly decreased cellular proliferation and cell viability (p<0.0001). In vivo, systemic treatment with EDC22 significantly decreased primary tumor growth rate in both an orthotopic mouse model (OSC-19) and a flank tumor mouse model (SCC-1) (p<0.05). In addition, EDC22 therapy resulted in a greater reduction in tumor growth in vivo compared to radiation monotherapy (p<0.05) and a similar reduction in tumor growth compared to cisplatin monotherapy. Combination therapy provided no significant further reduction in tumor growth relative to EDC22 monotherapy. CONCLUSION: EDC22 is a potent inhibitor of HNSCC cell proliferation in vitro and in vivo, warranting further investigations of its clinical potential in the treatment of HNSCC.

ERK1/2 signalling pathway is involved in CD147-mediated gastric cancer cell line SGC7901 proliferation and invasion.

This study aimed to investigate the role of CD147 in the progression of gastric cancer and the signalling pathway involved in CD147-mediated gastric cancer cell line SGC7901 proliferation and invasion. Short hairpin RNA (shRNA) expression vectors targeting CD147 were constructed to silence CD147, and the expression of CD147 was monitored by quantitative realtime reverse transcriptase polymerase chain reaction and Western blot and further confirmed by immunohistochemistry in vivo. Cell proliferation was determined by Cell Counting Kit-8 assay, the activities of matrix metalloproteinase (MMP)-2 and MMP-9 were determined by gelatin zymography, and the invasion of SGC7901 was determined by invasion assay. The phosphorylation and non-phosphorylation of the mitogen-activated protein kinases, extracellular signal-regulated kinase1/2 (ERK1/2), P38 and c-Jun NH2-terminal kinase were examined by Western blot. Additionally, the ERK1/2 inhibitor U0126 were used to confirm the signalling pathway involved in CD147-mediated SGC7901 progression. The BALB/c nude mice were used to study tumour progression in vivo. The results revealed that CD147 silencing inhibited the proliferation and invasion of SGC7901 cells, and down-regulated the activities of MMP-2 and MMP-9 and the phosphorylation of the ERK1/2 in SGC7901 cells. ERK1/2 inhibitor U0126 decreased the proliferation, and invasion of SGC7901 cells, and down-regulated the MMP-2 and MMP-9 activities. In a nude mouse model of subcutaneous xenografts, the tumour volume was significantly smaller in the SGC7901/shRNA group compared to the SGC7901 and SGC7901/snc-RNA group. Immunohistochemistry analysis showed that CD147 and p-ERK1/2 protein expressions were down-regulated in the SGC7901/shRNA2 group compared to the SGC7901 and SGC7901/snc-RNA group. These results suggest that ERK1/2 pathway involves in CD147-mediated gastric cancer growth and invasion. These findings further highlight the importance of CD147 in cancer progression, indicating that CD147 would be an attractive therapeutic target for gastric cancer.

Regulation of matrix metalloproteinases, tissue inhibitor of matrix metalloproteinase-1, and extracellular metalloproteinase inducer by interleukin-17 in human periodontal ligament fibroblasts.

INTRODUCTION: Under physiological conditions, matrix metalloproteinases (MMPs) are involved in the turnover of periapical tissue, and their activity is tightly regulated by tissue inhibitors of metalloproteinases (TIMPs). Disturbances in the balance between MMPs and TIMPs may result in excessive tissue destruction. In addition, the extracellular metalloproteinase inducer (EMMPRIN) capable of inducing MMPs may also play a role in the pathologic processes. This study aimed to investigate the effects of interleukin (IL)-17 on the mRNA expression and protein production of MMP-1, MMP-2, MMP-9, MMP-13, TIMP-1, and EMMPRIN through human periodontal ligament cells. METHODS: The cells were stimulated with IL-17 (1, 10, and 50 ng/mL) for different time periods. The mRNA levels of MMP-1, MMP-2, MMP-9, MMP-13, TIMP-1, and EMMPRIN were evaluated via quantitative real-time polymerase chain reaction analysis, whereas the protein secretion into the culture medium was assessed via enzyme-linked immunosorbent assay and zymography analysis. RESULTS: IL-17 significantly up-regulated MMP-1 and MMP-13 mRNA expression but down-regulated MMP-2, MMP-9, and TIMP-1 mRNA expression. Furthermore, IL-17 (50 ng/mL) increased the secreted protein level of MMP-1 and MMP-13 and conversely reduced the level of MMP-2, MMP-9, and TIMP-1. However, IL-17 exerted no effect on EMMPRIN mRNA or protein secretion. CONCLUSIONS: This study first reported the ability of IL-17 to regulate MMP and TIMP-1 production through human periodontal ligament cells, a phenomenon that may contribute to periapical tissue destruction.

5-HT1A and 5-HT7 receptor crosstalk in the regulation of emotional memory: implications for effects of selective serotonin reuptake inhibitors.

This study utilized pharmacological manipulations to analyze the role of direct and indirect activation of 5-HT(7) receptors (5-HT(7)Rs) in passive avoidance learning by assessing emotional memory in male C57BL/6J mice. Additionally, 5-HT(7)R binding affinity and 5-HT(7)R-mediated protein phosphorylation of downstream signaling targets were determined. Elevation of 5-HT by the selective serotonin reuptake inhibitor (SSRI) fluoxetine had no effect by itself, but facilitated emotional memory performance when combined with the 5-HT(1A)R antagonist NAD-299. This facilitation was blocked by the selective 5-HT(7)R antagonist SB269970, revealing excitatory effects of the SSRI via 5-HT(7)Rs. The enhanced memory retention by NAD-299 was blocked by SB269970, indicating that reduced activation of 5-HT(1A)Rs results in enhanced 5-HT stimulation of 5-HT(7)Rs. The putative 5-HT(7)R agonists LP-44 when administered systemically and AS19 when administered both systemically and into the dorsal hippocampus failed to facilitate memory. This finding is consistent with the low efficacy of LP-44 and AS19 to stimulate protein phosphorylation of 5-HT(7)R-activated signaling cascades. In contrast, increasing doses of the dual 5-HT(1A)R/5-HT(7)R agonist 8-OH-DPAT impaired memory, while co-administration with NAD-299 facilitated of emotional memory in a dose-dependent manner. This facilitation was blocked by SB269970 indicating 5-HT(7)R activation by 8-OH-DPAT. Dorsohippocampal infusion of 8-OH-DPAT impaired passive avoidance retention through hippocampal 5-HT(1A)R activation, while 5-HT(7)Rs appear to facilitate memory processes in a broader cortico-limbic network and not the hippocampus alone.

Expression of matrix metalloproteinase-1, matrix metalloproteinase-2 and extracellular metalloproteinase inducer in human periodontal ligament cells stimulated with interleukin-1 beta.

BACKGROUND AND OBJECTIVES: Matrix metalloproteinases (MMPs), produced by both infiltrating and resident cells of the periodontium, play important roles in physiologic and pathologic events. Both interleukin-1 beta and extracellular MMP inducer can stimulate the expression of MMPs, which in turn leads to breakdown of the periodontium. However, it is currently unknown whether interleukin-1 beta up-regulates MMPs through stimulating the expression of extracellular MMP inducer. The aims of this study were to investigate the effect of interleukin-1 beta on the expression of MMP-1, MMP-2 and extracellular MMP inducer in human periodontal ligament cells and to evaluate whether the regulation of MMP-1 and MMP-2 by this cytokine occurred through an effect on extracellular MMP inducer expression. MATERIAL AND METHODS: Cultured human periodontal ligament cells were treated with varying concentrations (0.01-10 ng/mL) of interleukin-1 beta at for 6, 12 and 24 h. Reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, gelatin zymography and western blotting were performed to measure the mRNA and protein levels of MMP-1, MMP-2 and extracellular MMP inducer. RESULTS: Basal levels of mRNA and protein for MMP-1, MMP-2 and extracellular MMP inducer were detected in untreated human periodontal ligament cells. Interleukin-1 beta significantly up-regulated the expression of MMP-1 and MMP-2 mRNA and protein (p < 0.05); however, the levels of mRNA and protein for extracellular MMP inducer were not significantly different (p > 0.05). In the culture medium, the concentration of MMP-1 was also increased significantly, but the concentration of MMP-1 was not related to the concentration of extracellular MMP inducer (R(2) = 0.2538, p > 0.05). CONCLUSION: Interleukin-1 beta up-regulated the levels of MMP-1 and MMP-2, but it did not alter the expression of extracellular MMP inducer. Expression of MMP-1 and MMP-2 might be elevated by interleukin-1 beta and extracellular MMP inducer via two different signal pathways.

Sinomenine influences capacity for invasion and migration in activated human monocytic THP-1 cells by inhibiting the expression of MMP-2, MMP-9, and CD147.

AIM: The aim of this study was to investigate the mechanism of the effects of Sinomenine (SIN) on the invasion and migration ability of activated human monocytic THP-1 cells (A-THP-1). Sinomenine is a pure alkaloid extracted from the Chinese medical plant Sinomenium acutum. METHODS: Human monocytic THP-1 cells were induced to differentiate into macrophages with phorbol 12-myristate 13-acetate (PMA). Cells were treated with different concentrations of SIN. The invasion and migration ability of cells was tested by in vitro transwell assays. The levels of CD147 and MMPs were evaluated by flow cytometric analysis and zymographic analysis, respectively. The mRNA expression of CD147, MMP-2, and MMP-9 was measured by RT-PCR. RESULTS: The invasion and migration ability of A-THP-1 cells was significantly inhibited by SIN in a concentration-dependent fashion; at the same time, the levels of CD147, MMP-2, and MMP-9 were markedly down-regulated. This inhibitory effect was most notable at concentrations of 0.25 mmol/L and 1.00 mmol/L (P<0.01). CONCLUSION: A possible mechanism of the inhibitory effect of SIN on cell invasion and migration ability is repression of the expression of MMP-2 and MMP-9, which strongly correlates with the inhibition of CD147 activity.

Blocking CD147 induces cell death in cancer cells through impairment of glycolytic energy metabolism.

CD147 is a multifunctional transmembrane protein and promotes cancer progression. We found that the anti-human CD147 mouse monoclonal antibody MEM-M6/1 strongly induces necrosis-like cell death in LoVo, HT-29, WiDr, and SW620 colon cancer cells and A2058 melanoma cells, but not in WI-38 and TIG-113 normal fibroblasts. Silencing or overexpression of CD147 in LoVo cells enhanced or decreased the MEM-M6/1 induced cell death, respectively. CD147 is known to form complex with proton-linked monocarboxylate transporters (MCTs), which is critical for lactate transport and intracellular pH (pHi) homeostasis. In LoVo cells, CD147 and MCT-1 co-localized on the cell surface, and MEM-M6/1 inhibited the association of these molecules. MEM-M6/1 inhibited lactate uptake, lactate release, and reduced pHi. Further, the induction of acidification was parallel to the decrease of the glycolytic flux and intracellular ATP levels. These effects were not found in the normal fibroblasts. As cancer cells depend on glycolysis for their energy production, CD147 inhibition might induce cell death specific to cancer cells.